TY - JOUR
A1 - Čuklina, Jelena
A1 - Hahn, Julia
A1 - Imakaev, Maxim
A1 - Omasits, Ulrich
A1 - Förstner, Konrad U.
A1 - Ljubimov, Nikolay
A1 - Goebel, Melanie
A1 - Pessi, Gabriella
A1 - Fischer, Hans-Martin
A1 - Ahrens, Christian H.
A1 - Gelfand, Mikhail S.
A1 - Evguenieva-Hackenberg, Elena
T1 - Genome-wide transcription start site mapping of Bradyrhizobium japonicum grown free-living or in symbiosis - a rich resource to identify new transcripts, proteins and to study gene regulation
JF - BMC Genomics
N2 - Background
Differential RNA-sequencing (dRNA-seq) is indispensable for determination of primary transcriptomes. However, using dRNA-seq data to map transcriptional start sites (TSSs) and promoters genome-wide is a bioinformatics challenge. We performed dRNA-seq of Bradyrhizobium japonicum USDA 110, the nitrogen-fixing symbiont of soybean, and developed algorithms to map TSSs and promoters.
Results
A specialized machine learning procedure for TSS recognition allowed us to map 15,923 TSSs: 14,360 in free-living bacteria, 4329 in symbiosis with soybean and 2766 in both conditions. Further, we provide proteomic evidence for 4090 proteins, among them 107 proteins corresponding to new genes and 178 proteins with N-termini different from the existing annotation (72 and 109 of them with TSS support, respectively). Guided by proteomics evidence, previously identified TSSs and TSSs experimentally validated here, we assign a score threshold to flag 14 % of the mapped TSSs as a class of lower confidence. However, this class of lower confidence contains valid TSSs of low-abundant transcripts. Moreover, we developed a de novo algorithm to identify promoter motifs upstream of mapped TSSs, which is publicly available, and found motifs mainly used in symbiosis (similar to RpoN-dependent promoters) or under both conditions (similar to RpoD-dependent promoters). Mapped TSSs and putative promoters, proteomic evidence and updated gene annotation were combined into an annotation file.
Conclusions
The genome-wide TSS and promoter maps along with the extended genome annotation of B. japonicum represent a valuable resource for future systems biology studies and for detailed analyses of individual non-coding transcripts and ORFs. Our data will also provide new insights into bacterial gene regulation during the agriculturally important symbiosis between rhizobia and legumes.
KW - Bradyrhizobium
KW - RNA-seq
KW - Promoter prediction
KW - Genome re-annotation
KW - Internal transcription start site
KW - Nodule
KW - Transcription start site
KW - Proteogenomics
KW - Antisense RNA
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164565
VL - 17
ER -
TY - JOUR
A1 - Üçeyler, Nurcan
A1 - Schäfer, Kristina A.
A1 - Mackenrodt, Daniel
A1 - Sommer, Claudia
A1 - Müllges, Wolfgang
T1 - High-Resolution Ultrasonography of the Superficial Peroneal Motor and Sural Sensory Nerves May Be a Non-invasive Approach to the Diagnosis of Vasculitic Neuropathy
JF - Frontiers in Neurology
N2 - High-resolution ultrasonography (HRUS) is an emerging new tool in the investigation of peripheral nerves. We set out to assess the utility of HRUS performed at lower extremity nerves in peripheral neuropathies. Nerves of 26 patients with polyneuropathies of different etiologies and 26 controls were investigated using HRUS. Patients underwent clinical, laboratory, electrophysiological assessment, and a diagnostic sural nerve biopsy as part of the routine work-up. HRUS was performed at the sural, tibial, and the common, superficial, and deep peroneal nerves. The superficial peroneal nerve longitudinal diameter (LD) distinguished best between the groups: patients with immune-mediated neuropathies (n = 13, including six with histology-proven vasculitic neuropathy) had larger LD compared to patients with non-immune-mediated neuropathies (p < 0.05) and to controls (p < 0.001). Among all subgroups, patients with vasculitic neuropathy showed the largest superficial peroneal nerve LD (p < 0.001) and had a larger sural nerve cross-sectional area when compared with disease controls (p < 0.001). Enlargement of the superficial peroneal and sural nerves as detected by HRUS may be a useful additional finding in the differential diagnosis of vasculitic and other immune-mediated neuropathies.
KW - peripheral neuropathy
KW - nerve ultrasonography
KW - vasculitis
KW - sural nerve
KW - superficial peroneal nerve
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146671
VL - 7
IS - 48
ER -
TY - JOUR
A1 - Üçeyler, Nurcan
A1 - Schröter, Nils
A1 - Kafke, Waldemar
A1 - Kramer, Daniela
A1 - Wanner, Christoph
A1 - Weidemann, Frank
A1 - Sommer, Claudia
T1 - Skin Globotriaosylceramide 3 Load Is Increased in Men with Advanced Fabry Disease
JF - PLoS ONE
N2 - Background
The X-chromosomally linked life-limiting Fabry disease (FD) is associated with deposits of the sphingolipid globotriaosylceramide 3 (Gb3) in various tissues. Skin is easily accessible and may be used as an additional diagnostic and follow-up medium. Our aims were to visualize skin Gb3 deposits in FD patients applying immunofluorescence and to determine if cutaneous Gb3 load correlates with disease severity.
Methods
At our Fabry Center for Interdisciplinary Therapy we enrolled 84 patients with FD and 27 healthy controls. All subjects underwent 5-mm skin punch biopsy at the lateral lower leg and the back. Skin samples were processed for immunohistochemistry using antibodies against CD77 (i.e. Gb3). Cutaneous Gb3 deposition was quantified in a blinded manner and correlated to clinical data.
Results
We found that Gb3 load was higher in distal skin of male FD patients compared to healthy controls (p<0.05). Men (p<0.01) and women (p<0.05) with a classic FD phenotype had higher distal skin Gb3 load than healthy controls. Men with advanced disease as reflected by impaired renal function, and men and women with small fiber neuropathy had more Gb3 deposits in distal skin samples than males with normal renal function (p<0.05) and without small fiber neuropathy. Gb3 deposits were not different between patients with and without enzyme replacement therapy.
Conclusions
Immunofluorescence on minimally invasive skin punch biopsies may be useful as a tool for assessment and follow-up in FD patients.
KW - biopsy
KW - neuropathy
KW - Fabry disease
KW - renal system
KW - immunofluorescence
KW - enzyme replacement therapy
KW - skin diseases
KW - nerve fibers
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-178856
VL - 11
IS - 11
ER -
TY - JOUR
A1 - Üçeyler, Nurcan
A1 - Biko, Lydia
A1 - Hose, Dorothea
A1 - Hoffmann, Lukas
A1 - Sommer, Claudia
T1 - Comprehensive and differential long-term characterization of the alpha-galactosidase A deficient mouse model of Fabry disease focusing on the sensory system and pain development
JF - Molecular Pain
N2 - Fabry disease is an X-linked lysosomal storage disorder due to impaired activity of alpha-galactosidase A with intracellular accumulation of globotriaosylceramide. Associated small fiber pathology leads to characteristic pain in Fabry disease. We systematically assessed sensory system, physical activity, metabolic parameters, and morphology of male and female mice with alpha-galactosidase A deficiency (Fabry ko) from 2 to 27 months of age and compared results with those of age- and gender-matched wild-type littermates of C57Bl/6J background. Results From the age of two months, male and female Fabry mice showed mechanical hypersensitivity (p < 0.001 each) compared to wild-type littermates. Young Fabry ko mice of both genders were hypersensitive to heat stimulation (p < 0.01) and developed heat hyposensitivity with aging (p < 0.05), while cold hyposensitivity was present constantly in young (p < 0.01) and old (p < 0.05) Fabry ko mice compared to wild-type littermates. Stride angle increased only in male Fabry ko mice with aging (p < 0.01) in comparison to wild-type littermates. Except for young female mice, male (p < 0.05) and female (p < 0.01) Fabry ko mice had a higher body weight than wild-type littermates. Old male Fabry ko mice were physically less active than their wild-type littermates (p < 0.05), had lower chow intake (p < 0.001), and lost more weight (p < 0.001) in a one-week treadmill experiment than wild-type littermates. Also, Fabry ko mice showed spontaneous pain protective behavior and developed orofacial dysmorphism resembling patients with Fabry disease.
Conclusions. Mice with alpha-galactosidase A deficiency show age-dependent and distinct deficits of the sensory system. alpha-galactosidase A-deficient mice seem to model human Fabry disease and may be helpful when studying the pathophysiology of Fabry-associated pain.
KW - Fabry disease
KW - alpha-galactosidase A
KW - mouse model
KW - pain
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147562
VL - 12
IS - 1744806916646370
ER -
TY - THES
A1 - Zott, Maximilian
T1 - Extreme Value Theory in Higher Dimensions - Max-Stable Processes and Multivariate Records
T1 - Höherdimensionale Extremwerttheorie - Max-Stabile Prozesse und Multivariate Rekorde
N2 - Die Extremwerttheorie behandelt die stochastische Modellierung seltener und extremer Ereignisse. Während fundamentale Theorien in der klassischen Stochastik, wie etwa die Gesetze der großen Zahlen oder der zentrale Grenzwertsatz das asymptotische Verhalten der Summe von Zufallsvariablen untersucht, liegt in der Extremwerttheorie der Fokus auf dem Maximum oder dem Minimum einer Menge von Beobachtungen. Die Grenzverteilung des normierten Stichprobenmaximums unter einer Folge von unabhängigen und identisch verteilten Zufallsvariablen kann durch sogenannte max-stabile Verteilungen charakterisiert werden.
In dieser Dissertation werden verschiedene Aspekte der Theorie der max-stabilen Zufallsvektoren und stochastischen Prozesse behandelt. Insbesondere wird der Begriff der 'Differenzierbarkeit in Verteilung' eines max-stabilen Prozesses eingeführt und untersucht. Ferner werden 'verallgemeinerte max-lineare Modelle' eingeführt, um einen bekannten max-stabilen Zufallsvektor durch einen max-stabilen Prozess zu interpolieren. Darüber hinaus wird der Zusammenhang von extremwerttheoretischen Methoden mit der Theorie der multivariaten Rekorde hergestellt. Insbesondere werden sogenannte 'vollständige' und 'einfache' Rekorde eingeführt, und deren asymptotisches Verhalten untersucht.
N2 - Extreme value theory is concerned with the stochastic modeling of rare and extreme events. While fundamental theories of classical stochastics - such as the laws of small numbers or the central limit theorem - are used to investigate the asymptotic behavior of the sum of random variables, extreme value theory focuses on the maximum or minimum of a set of observations. The limit distribution of the normalized sample maximum among a sequence of independent and identically distributed random variables can be characterized by means of so-called max-stable distributions.
This dissertation concerns with different aspects of the theory of max-stable random vectors and stochastic processes. In particular, the concept of 'differentiability in distribution' of a max-stable process is introduced and investigated. Moreover, 'generalized max-linear models' are introduced in order to interpolate a known max-stable random vector by a max-stable process. Further, the connection between extreme value theory and multivariate records is established. In particular, so-called 'complete' and 'simple' records are introduced as well as it is examined their asymptotic behavior.
KW - Stochastischer Prozess
KW - Extremwertstatistik
KW - max-stable process
KW - max-linear model
KW - Wahrscheinlichkeitsrechnung
KW - Rekord
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-136614
ER -
TY - JOUR
A1 - Zlamy, Manuela
A1 - Almanzar, Giovanni
A1 - Parson, Walther
A1 - Schmidt, Christian
A1 - Leierer, Johannes
A1 - Weinberger, Birgit
A1 - Jeller, Verena
A1 - Unsinn, Karin
A1 - Eyrich, Matthias
A1 - Würzner, Reinhard
A1 - Prelog, Martina
T1 - Efforts of the human immune system to maintain the peripheral CD8+ T cell compartment after childhood thymectomy
JF - Immunity & Ageing
N2 - Background
Homeostatic mechanisms to maintain the T cell compartment diversity indicate an ongoing process of thymic activity and peripheral T cell renewal during human life. These processes are expected to be accelerated after childhood thymectomy and by the influence of cytomegalovirus (CMV) inducing a prematurely aged immune system.
The study aimed to investigate proportional changes and replicative history of CD8+ T cells, of recent thymic emigrants (RTEs) and CD103+ T cells (mostly gut-experienced) and the role of Interleukin-(IL)-7 and IL-7 receptor (CD127)-expressing T cells in thymectomized patients compared to young and old healthy controls.
Results
Decreased proportions of naive and CD31 + CD8+ T cells were demonstrated after thymectomy, with higher proliferative activity of CD127-expressing T cells and significantly shorter relative telomere lengths (RTLs) and lower T cell receptor excision circles (TRECs). Increased circulating CD103+ T cells and a skewed T cell receptor (TCR) repertoire were found after thymectomy similar to elderly persons. Naive T cells were influenced by age at thymectomy and further decreased by CMV.
Conclusions
After childhood thymectomy, the immune system demonstrated constant efforts of the peripheral CD8+ T cell compartment to maintain homeostasis. Supposedly it tries to fill the void of RTEs by peripheral T cell proliferation, by at least partly IL-7-mediated mechanisms and by proportional increase of circulating CD103+ T cells, reminiscent of immune aging in elderly. Although other findings were less significant compared to healthy elderly, early thymectomy demonstrated immunological alterations of CD8+ T cells which mimic features of premature immunosenescence in humans.
KW - thymectomy
KW - naive T cells
KW - TRECs
KW - TCR diversity
KW - CMV
KW - CD8
KW - telomeres
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146497
VL - 13
IS - 3
ER -
TY - JOUR
A1 - Zipfel, Julian
A1 - Eyrich, Matthias
A1 - Schlegel, Paul-Gerhardt
A1 - Wiegering, Verena
T1 - Disturbed B cell and DC-Homeostasis in Pediatric cGVHD Patients-Cocultivation Experiments and Review of the Literature
JF - Clinics in Oncology
N2 - B cells and DCs are suspected to play an important role in the pathogenesis of cGvHD, which is a serious complication of HSCT with high morbidity. It is characterized by immune responses of donor immune cells against recipient-derived antigens. athogenesis is not yet fully understood, however reconstitution of B cells after HSCT has similarities to physiologic ontogeny. Immunophenotyping and co-cultivation-experiments of B cells and DCs from pediatric patients with cGvHD as well as healthy donors were conducted. Significant differences between patients and healthy donors were observed with increased memory, transitional, CD69+ and CD86+ phenotype and lower levels of naïve B cells due to apoptosis. Co-cultivation revealed this to be primarily B cell-dependent without major effects of and with DCs. There was a decreased CD11c- phenotype in patients and less apoptosis of DCs. Our data suggest a disturbed homeostasis in B cells with increased memory phenotype in patients, whereas DCs could not influence these differences, therefore DCs are not imposing as promising targets. B cell-dependent approaches should be further investigated.
KW - B cell
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147914
VL - 1
IS - 1097
ER -
TY - JOUR
A1 - Zinner, Christoph
A1 - Morales-Alamo, David
A1 - Ørtenblad, Niels
A1 - Larsen, Filip J.
A1 - Schiffer, Tomas A.
A1 - Willis, Sarah J.
A1 - Gelabert-Rebato, Miriam
A1 - Perez-Valera, Mario
A1 - Boushel, Robert
A1 - Calbet, Jose A. L.
A1 - Holmberg, Hans-Christer
T1 - The Physiological Mechanisms of Performance Enhancement with Sprint Interval Training Differ between the Upper and Lower Extremities in Humans
JF - Frontiers in Physiology
N2 - To elucidate the mechanisms underlying the differences in adaptation of arm and leg muscles to sprint training, over a period of 11 days 16 untrained men performed six sessions of 4–6 × 30-s all-out sprints (SIT) with the legs and arms, separately, with a 1-h interval of recovery. Limb-specific VO2peak, sprint performance (two 30-s Wingate tests with 4-min recovery), muscle efficiency and time-trial performance (TT, 5-min all-out) were assessed and biopsies from the m. vastus lateralis and m. triceps brachii taken before and after training. VO2peak and Wmax increased 3–11% after training, with a more pronounced change in the arms (P < 0.05). Gross efficiency improved for the arms (+8.8%, P < 0.05), but not the legs (−0.6%). Wingate peak and mean power outputs improved similarly for the arms and legs, as did TT performance. After training, VO2 during the two Wingate tests was increased by 52 and 6% for the arms and legs, respectively (P < 0.001). In the case of the arms, VO2 was higher during the first than second Wingate test (64 vs. 44%, P < 0.05). During the TT, relative exercise intensity, HR, VO2, VCO2, VE, and Vt were all lower during arm-cranking than leg-pedaling, and oxidation of fat was minimal, remaining so after training. Despite the higher relative intensity, fat oxidation was 70% greater during leg-pedaling (P = 0.017). The aerobic energy contribution in the legs was larger than for the arms during the Wingate tests, although VO2 for the arms was enhanced more by training, reducing the O2 deficit after SIT. The levels of muscle glycogen, as well as the myosin heavy chain composition were unchanged in both cases, while the activities of 3-hydroxyacyl-CoA-dehydrogenase and citrate synthase were elevated only in the legs and capillarization enhanced in both limbs. Multiple regression analysis demonstrated that the variables that predict TT performance differ for the arms and legs. The primary mechanism of adaptation to SIT by both the arms and legs is enhancement of aerobic energy production. However, with their higher proportion of fast muscle fibers, the arms exhibit greater plasticity.
KW - high-intensity training
KW - lower body
KW - performance
KW - triceps brachii
KW - upper body
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165257
VL - 7
IS - 426
ER -
TY - JOUR
A1 - Zinner, C.
A1 - Krueger, M.
A1 - Reed, J. L.
A1 - Kohl-Bareis, M.
A1 - Holmberg, H. C.
A1 - Sperlich, B.
T1 - Exposure to a combination of heat and hyperoxia during cycling at submaximal intensity does not alter thermoregulatory responses
JF - Biology of Sport
N2 - In this study, we tested the hypothesis that breathing hyperoxic air (F\(_{in}\)O\(_2\) = 0.40) while exercising in a hot environment exerts negative effects on the total tissue level of haemoglobin concentration (tHb); core (T\(_{core}\)) and skin (T\(_{skin}\)) temperatures; muscle activity; heart rate; blood concentration of lactate; pH; partial pressure of oxygen (P\(_a\)O\(_2\)) and carbon dioxide; arterial oxygen saturation (S\(_a\)O\(_2\)); and perceptual responses. Ten well-trained male athletes cycled at submaximal intensity at 21°C or 33°C in randomized order: first for 20 min while breathing normal air (FinO\(_2\) = 0.21) and then 10 min with F\(_{in}\)O\(_2\) = 0.40 (HOX). At both temperatures, S\(_a\)O\(_2\) and P\(_a\)O\(_2\), but not tHb, were increased by HOX. Tskin and perception of exertion and thermal discomfort were higher at 33°C than 21°C (p < 0.01), but independent of F\(_{in}\)O\(_2\). T\(_{core}\) and muscle activity were the same under all conditions (p > 0.07). Blood lactate and heart rate were higher at 33°C than 21°C. In conclusion, during 30 min of submaximal cycling at 21°C or 33°C, T\(_{core}\), T\(_{skin}\) and T\(_{body}\), tHb, muscle activity and ratings of perceived exertion and thermal discomfort were the same under normoxic and hyperoxic conditions. Accordingly, breathing hyperoxic air (F\(_{in}\)O\(_2\) = 0.40) did not affect thermoregulation under these conditions.
KW - heat stress
KW - hyperthermia
KW - skin blood flow
KW - thermoregulation
KW - vasoconstriction
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160993
VL - 33
IS - 1
ER -
TY - THES
A1 - Ziegler, Christiane
T1 - Epigenetic Mechanisms in the Pathogenesis and Therapy of Anxiety Disorders
T1 - Epigenetische Mechanismen in der Pathogenese und Therapie von Angsterkrankungen
N2 - Anxiety disorders (AD) are common, disabling mental disorders, which constitute the most prevalent mental health condition conveying a high individual and socioeconomic burden. Social anxiety disorder (SAD), i.e. fear in social situations particularly when subjectively scrutinized by others, is the second most common anxiety disorder with a life time prevalence of 10%. Panic disorder (PD) has a life time prevalence of 2-5% and is characterized by recurrent and abrupt surges of intense fear and anticipatory anxiety, i.e. panic attacks, occurring suddenly and unexpected without an apparent cue.
In recent years, psychiatric research increasingly focused on epigenetic mechanisms such as DNA methylation as a possible solution for the problem of the so-called “hidden heritability”, which conceptualizes the fact that the genetic risk variants identified so far only explain a small part of the estimated heritability of mental disorders.
In the first part of this thesis, oxytocin receptor (OXTR) gene methylation was investigated regarding its role in the pathogenesis of social anxiety disorder. In summary, OXTR methylation patterns were implicated in different phenotypes of social anxiety disorder on a categorical, neuropsychological, neuroendocrinological as well as on a neural network level. The results point towards a multilevel role of OXTR gene hypomethylation particularly at one CpG site (CpG3, Chr3: 8 809 437) within the protein coding region of the gene in SAD.
The second part of the thesis investigated monoamine oxidase A (MAOA) gene methylation regarding its role in the pathogenesis of panic disorder as well as – applying a psychotherapy-epigenetic approach – its dynamic regulation during the course of cognitive behavioural therapy (CBT) in PD patients. First, MAOA hypomethylation was shown to be associated with panic disorder as well as with panic disorder severity. Second, in patients responding to treatment MAOA hypomethylation was shown to be reversible up to the level of methylation in healthy controls after the course of CBT. This increase in MAOA methylation along with successful psychotherapeutic treatment was furthermore shown to be associated with symptom improvement regarding agoraphobic avoidance in an independent replication sample of non-medicated patients with PD.
Taken together, in the future the presently identified epigenetic patterns might contribute to establishing targeted preventive interventions and personalized treatment options for social anxiety disorder or panic disorder, respectively.
N2 - Angsterkrankungen sind die häufigsten psychischen Erkrankungen, welche in hohem Maße den Alltag der Betroffenen beeinträchtigen und eine große sozioökonomische Belastung darstellen. Eine der häufigsten Formen von Angsterkrankungen bildet die soziale Phobie, d.h. die Angst vor sozialen Situationen, in denen man im Mittelpunkt der Aufmerksamkeit steht, mit einer Lebenszeit-Prävalenz von circa 10%. Die Panikstörung, charakterisiert durch das wiederholte und unerwartete Auftreten von Panikattacken, ist eine weitere Form der Angsterkrankungen mit einer Lebenszeit-Prävalenz von circa 2-5%.
Epigenetische Mechanismen, wie zum Beispiel die DNA Methylierung, rücken in den letzten Jahren immer weiter in den Fokus der psychiatrischen Forschung. Hier werden sie als eine mögliche Lösung für das Problem der „hidden heritability“ (versteckte Heritabilität) angesehen.
Im ersten Teil dieser Arbeit wurde die DNA Methylierung des Oxytozinrezeptorgens (OXTR) hinsichtlich ihrer Rolle in der Pathogenese der sozialen Phobie untersucht. Hierbei konnte eine verringerte Methylierung des Gens, speziell an einem CpG-Dinukleotid (CpG3, Chr3: 8 809 437) innerhalb der protein-kodierenden Genregion, auf verschiedenen Ebenen mit der Erkrankung an sozialer Phobie, dimensionalen Maßen der Erkrankungsschwere sowie der Stressverarbeitung auf neuro-endokrinologischer und neuronaler Ebene in Verbindung gebracht werden.
Der zweite Teil dieser Arbeit beschäftigt sich mit der Rolle von DNA Methylierungsmustern des Monoaminooxidase A (MAOA) Gens in der Pathogenese und der Therapie der Panikstörung. Zum einen konnte gezeigt werden, dass eine verringerte MAOA Methylierung mit dem Auftreten von Panikstörung sowie mit einer erhöhten Symptomschwere assoziiert ist. Zum anderen zeigten Patienten, welche auf eine kognitive Verhaltenstherapie (KVT) ansprachen, eine signifikante Erhöhung der MAOA Methylierung nach der Therapie, welche zusätzlich in einer unabhängigen Stichprobe mit einer Verringerung der Symptomschwere assoziiert war. Diese Veränderung zeigte sich jedoch nicht in Patienten, welche nicht auf die KVT ansprachen.
Zusammenfassend können beide im Rahmen dieser Arbeit untersuchten epigenetischen Muster und deren Rolle in der Pathogenese der sozialen Phobie sowie der Panikstörung zur Etablierung personalisierter Therapiemöglichkeiten wie auch targetierter präventiver Interventionen beitragen.
KW - Angst
KW - Psychische Störung
KW - DNA-Methylierung
KW - Panikstörung
KW - Soziale Phobie
KW - Angsterkrankungen
KW - Epigenetische Mechanismen
KW - Epigenetik
KW - Methylierung
KW - DNS
KW - Angsterkrankungen
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146815
ER -
TY - JOUR
A1 - Ziegler, C.
A1 - Richter, J.
A1 - Mahr, M.
A1 - Gajewska, A.
A1 - Schiele, M.A.
A1 - Gehrmann, A.
A1 - Schmidt, B.
A1 - Lesch, K.-P.
A1 - Lang, T.
A1 - Helbig-Lang, S.
A1 - Pauli, P.
A1 - Kircher, T.
A1 - Reif, A.
A1 - Rief, W.
A1 - Vossbeck-Elsebusch, A.N.
A1 - Arolt, V.
A1 - Wittchen, H.-U.
A1 - Hamm, A.O.
A1 - Deckert, J.
A1 - Domschke, K.
T1 - MAOA gene hypomethylation in panic disorder-reversibility of an epigenetic risk pattern by psychotherapy
JF - Translational Psychiatry
N2 - Epigenetic signatures such as methylation of the monoamine oxidase A (MAOA) gene have been found to be altered in panic disorder (PD). Hypothesizing temporal plasticity of epigenetic processes as a mechanism of successful fear extinction, the present psychotherapy-epigenetic study for we believe the first time investigated MAOA methylation changes during the course of exposure-based cognitive behavioral therapy (CBT) in PD. MAOA methylation was compared between N=28 female Caucasian PD patients (discovery sample) and N=28 age- and sex-matched healthy controls via direct sequencing of sodium bisulfite-treated DNA extracted from blood cells. MAOA methylation was furthermore analyzed at baseline (T0) and after a 6-week CBT (T1) in the discovery sample parallelized by a waiting time in healthy controls, as well as in an independent sample of female PD patients (N=20). Patients exhibited lower MAOA methylation than healthy controls (P<0.001), and baseline PD severity correlated negatively with MAOA methylation (P=0.01). In the discovery sample, MAOA methylation increased up to the level of healthy controls along with CBT response (number of panic attacks; T0-T1: +3.37±2.17%), while non-responders further decreased in methylation (-2.00±1.28%; P=0.001). In the replication sample, increases in MAOA methylation correlated with agoraphobic symptom reduction after CBT (P=0.02-0.03). The present results support previous evidence for MAOA hypomethylation as a PD risk marker and suggest reversibility of MAOA hypomethylation as a potential epigenetic correlate of response to CBT. The emerging notion of epigenetic signatures as a mechanism of action of psychotherapeutic interventions may promote epigenetic patterns as biomarkers of lasting extinction effects.
KW - Adult
KW - Case-Control Studies
KW - Cognitive Therapy
KW - DNA Methylation
KW - Epigenesis
KW - Genetic
KW - Female
KW - Humans
KW - Monoamine Oxidase/genetics
KW - Panic Disorder/genetics
KW - Panic Disorder/therapy
KW - Sequence Analysis
KW - DNA
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164422
IS - 6
ER -
TY - JOUR
A1 - Zhu, Min
A1 - Shabala, Lana
A1 - Cuin, Tracey A.
A1 - Huang, Xin
A1 - Zhou, Meixue
A1 - Munns, Rana
A1 - Shabala, Sergey
T1 - Nax loci affect SOS1-like Na\(^+\)/H\(^+\) exchanger expression and activity in wheat
JF - Journal of Experimental Botany
N2 - Salinity stress tolerance in durum wheat is strongly associated with a plant's ability to control Na\(^+\) delivery to the shoot. Two loci, termed Nax1 and Nax2, were recently identified as being critical for this process and the sodium transporters HKT1;4 and HKT1; 5 were identified as the respective candidate genes. These transporters retrieve Na\(^+\) from the xylem, thus limiting the rates of Na\(^+\) transport from the root to the shoot. In this work, we show that the Nax loci also affect activity and expression levels of the SOS1-like Na\(^+\)/H\(^+\) exchanger in both root cortical and stelar tissues. Net Na\(^+\) efflux measured in isolated steles from salt-treated plants, using the non-invasive ion flux measuring MIFE technique, decreased in the sequence: Tamaroi (parental line)>Nax1=Nax2>Nax1:Nax2 lines. This efflux was sensitive to amiloride (a known inhibitor of the Na\(^+\)/H\(^+\) exchanger) and was mirrored by net H\(^+\) flux changes. TdSOS1 relative transcript levels were 6-10-fold lower in Nax lines compared with Tamaroi. Thus, it appears that Nax loci confer two highly complementary mechanisms, both of which contribute towards reducing the xylem Na\(^+\) content. One enhances the retrieval of Na\(^+\) back into the root stele via HKT1;4 or HKT1;5, whilst the other reduces the rate of Na\(^+\) loading into the xylem via SOS1. It is suggested that such duality plays an important adaptive role with greater versatility for responding to a changing environment and controlling Na\(^+\) delivery to the shoot.
KW - HKT transporter
KW - potassium
KW - salinity stress
KW - sequestration
KW - sodium
KW - xylem loading
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-190908
VL - 67
IS - 3
ER -
TY - JOUR
A1 - Zhu, Min
A1 - Shabala, Lana
A1 - Cuin, Tracey A
A1 - Huang, Xin
A1 - Zhou, Meixue
A1 - Munns, Rana
A1 - Shabala, Sergey
T1 - Nax loci affect SOS1-like Na\(^{+}\)/H\(^{+}\) exchanger expression and activity in wheat
JF - Journal of Experimental Botany
N2 - Salinity stress tolerance in durum wheat is strongly associated with a plant’s ability to control Na\(^{+}\) delivery to the shoot. Two loci, termed Nax1 and Nax2, were recently identified as being critical for this process and the sodium transporters HKT1;4 and HKT1;5 were identified as the respective candidate genes. These transporters retrieve Na\(^{+}\) from the xylem, thus limiting the rates of Na\(^{+}\) transport from the root to the shoot. In this work, we show that the Nax loci also affect activity and expression levels of the SOS1-like Na\(^{+}\)/H\(^{+}\) exchanger in both root cortical and stelar tissues. Net Na\(^{+}\) efflux measured in isolated steles from salt-treated plants, using the non-invasive ion flux measuring MIFE technique, decreased in the sequence: Tamaroi (parental line)>Nax1=Nax2>Nax1:Nax2 lines. This efflux was sensitive to amiloride (a known inhibitor of the Na\(^{+}\)/H\(^{+}\) exchanger) and was mirrored by net H\(^{+}\) flux changes. TdSOS1 relative transcript levels were 6–10-fold lower in Nax lines compared with Tamaroi. Thus, it appears that Nax loci confer two highly complementary mechanisms, both of which contribute towards reducing the xylem Na\(^{+}\) content. One enhances the retrieval of Na\(^{+}\) back into the root stele via HKT1;4 or HKT1;5, whilst the other reduces the rate of Na\(^{+}\) loading into the xylem via SOS1. It is suggested that such duality plays an important adaptive role with greater versatility for responding to a changing environment and controlling Na\(^{+}\) delivery to the shoot.
KW - HKT transporter
KW - potassium
KW - salinity stress
KW - sequestration
KW - sodium
KW - xylem loading
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-150236
VL - 67
IS - 3
ER -
TY - JOUR
A1 - Zhou, Sijie
A1 - Allison, Brendan Z.
A1 - Kübler, Andrea
A1 - Cichocki, Andrzej
A1 - Wang, Xingyu
A1 - Jin, Jing
T1 - Effects of Background Music on Objective and Subjective Performance Measures in an Auditory BCI
JF - Frontiers in Computational Neuroscience
N2 - Several studies have explored brain computer interface (BCI) systems based on auditory stimuli, which could help patients with visual impairments. Usability and user satisfaction are important considerations in any BCI. Although background music can influence emotion and performance in other task environments, and many users may wish to listen to music while using a BCI, auditory, and other BCIs are typically studied without background music. Some work has explored the possibility of using polyphonic music in auditory BCI systems. However, this approach requires users with good musical skills, and has not been explored in online experiments. Our hypothesis was that an auditory BCI with background music would be preferred by subjects over a similar BCI without background music, without any difference in BCI performance. We introduce a simple paradigm (which does not require musical skill) using percussion instrument sound stimuli and background music, and evaluated it in both offline and online experiments. The result showed that subjects preferred the auditory BCI with background music. Different performance measures did not reveal any significant performance effect when comparing background music vs. no background. Since the addition of background music does not impair BCI performance but is preferred by users, auditory (and perhaps other) BCIs should consider including it. Our study also indicates that auditory BCIs can be effective even if the auditory channel is simultaneously otherwise engaged.
KW - brain computer interface
KW - event-related potentials
KW - auditory
KW - music background
KW - audio stimulus
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165101
VL - 10
IS - 105
ER -
TY - JOUR
A1 - Zayats, T
A1 - Jacobsen, KK
A1 - Kleppe, R
A1 - Jacob, CP
A1 - Kittel-Schneider, S
A1 - Ribasés, M
A1 - Ramos-Quiroga, JA
A1 - Richarte, V
A1 - Casas, M
A1 - Mota, NR
A1 - Grevet, EH
A1 - Klein, M
A1 - Corominas, J
A1 - Bralten, J
A1 - Galesloot, T
A1 - Vasquez, AA
A1 - Herms, S
A1 - Forstner, AJ
A1 - Larsson, H
A1 - Breen, G
A1 - Asherson, P
A1 - Gross-Lesch, S
A1 - Lesch, KP
A1 - Cichon, S
A1 - Gabrielsen, MB
A1 - Holmen, OL
A1 - Bau, CHD
A1 - Buitelaar, J
A1 - Kiemeney, L
A1 - Faraone, SV
A1 - Cormand, B
A1 - Franke, B
A1 - Reif, A
A1 - Haavik, J
A1 - Johansson, S
T1 - Exome chip analyses in adult attention deficit hyperactivity disorder
JF - Translational Psychiatry
N2 - Attention-deficit/hyperactivity disorder (ADHD) is a highly heritable childhood-onset neuropsychiatric condition, often persisting into adulthood. The genetic architecture of ADHD, particularly in adults, is largely unknown. We performed an exome-wide scan of adult ADHD using the Illumina Human Exome Bead Chip, which interrogates over 250 000 common and rare variants. Participants were recruited by the International Multicenter persistent ADHD CollaboraTion (IMpACT). Statistical analyses were divided into 3 steps: (1) gene-level analysis of rare variants (minor allele frequency (MAF)<1%); (2) single marker association tests of common variants (MAF⩾1%), with replication of the top signals; and (3) pathway analyses. In total, 9365 individuals (1846 cases and 7519 controls) were examined. Replication of the most associated common variants was attempted in 9847 individuals (2077 cases and 7770 controls) using fixed-effects inverse variance meta-analysis. With a Bonferroni-corrected significance level of 1.82E−06, our analyses of rare coding variants revealed four study-wide significant loci: 6q22.1 locus (P=4.46E−08), where NT5DC1 and COL10A1 reside; the SEC23IP locus (P=6.47E−07); the PSD locus (P=7.58E−08) and ZCCHC4 locus (P=1.79E−06). No genome-wide significant association was observed among the common variants. The strongest signal was noted at rs9325032 in PPP2R2B (odds ratio=0.81, P=1.61E−05). Taken together, our data add to the growing evidence of general signal transduction molecules (NT5DC1, PSD, SEC23IP and ZCCHC4) having an important role in the etiology of ADHD. Although the biological implications of these findings need to be further explored, they highlight the possible role of cellular communication as a potential core component in the development of both adult and childhood forms of ADHD.
KW - chip analyses
KW - ADHD
KW - adulthood
KW - Illumina Human Exome Bead Chip
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-168297
VL - 6
IS - e923
ER -
TY - JOUR
A1 - Zahnert, Thomas
A1 - Löwenheim, Hubert
A1 - Beutner, Dirk
A1 - Hagen, Rudolf
A1 - Ernst, Arneborg
A1 - Pau, Hans-Wilhelm
A1 - Zehlicke, Thorsten
A1 - Kühne, Hilke
A1 - Friese, Natascha
A1 - Tropitzsch, Anke
A1 - Lüers, Jan-Christoffer
A1 - Mlynski, Robert
A1 - Todt, Ingo
A1 - Hüttenbrink, Karl-Bernd
T1 - Multicenter Clinical Trial of Vibroplasty Couplers to Treat Mixed/Conductive Hearing Loss: First Results
JF - Audiology and Neurotology
N2 - Objective: To evaluate the safety and effectiveness of round window (RW), oval window (OW), CliP and Bell couplers for use with an active middle ear implant. Methods: This is a multicenter, long-term, prospective trial with consecutive enrollment, involving 6 university hospitals in Germany. Bone conduction, air conduction, implant-aided warble-tone thresholds and Freiburger monosyllable word recognition scores were compared with unaided preimplantation results in 28 moderate-to-profound hearing-impaired patients after 12 months of follow-up. All patients had previously undergone failed reconstruction surgeries (up to 5 or more). In a subset of patients, additional speech tests at 12 months postoperatively were used to compare the aided with the unaided condition after implantation with the processor switched off. An established quality-of-life questionnaire for hearing aids was used to determine patient satisfaction. Results: Postoperative bone conduction remained stable. Mean functional gain for all couplers was 37 dB HL (RW = 42 dB, OW = 35 dB, Bell = 38 dB, CliP = 27 dB). The mean postoperative Freiburger monosyllable score was 71% at 65 dB SPL. The postimplantation mean SRT50 (speech reception in quiet for 50% understanding of words in sentences) improved on average by 23 dB over unaided testing and signal-to-noise ratios also improved in all patients. The International Outcome Inventory for Hearing Aids (IOI-HA)quality-of-life questionnaire was scored very positively by all patients. Conclusion: A significant improvement was seen with all couplers, and patients were satisfied with the device at 12 months postoperatively. These results demonstrate that an active implant is an advantage in achieving good hearing benefit in patients with prior failed reconstruction surgery.
KW - conductive hearing loss
KW - mixed hearing loss
KW - vibroplasty
KW - couplers
KW - middle ear implant
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-199129
SN - 1420-3030
SN - 1421-9700
N1 - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.
VL - 21
IS - 4
ER -
TY - JOUR
A1 - Yadav, Preeti
A1 - Selvaraj, Bhuvaneish T.
A1 - Bender, Florian L. P.
A1 - Behringer, Marcus
A1 - Moradi, Mehri
A1 - Sivadasan, Rajeeve
A1 - Dombert, Benjamin
A1 - Blum, Robert
A1 - Asan, Esther
A1 - Sauer, Markus
A1 - Julien, Jean-Pierre
A1 - Sendtner, Michael
T1 - Neurofilament depletion improves microtubule dynamics via modulation of Stat3/stathmin signaling
JF - Acta Neuropathologica
N2 - In neurons, microtubules form a dense array within axons, and the stability and function of this microtubule network is modulated by neurofilaments. Accumulation of neurofilaments has been observed in several forms of neurodegenerative diseases, but the mechanisms how elevated neurofilament levels destabilize axons are unknown so far. Here, we show that increased neurofilament expression in motor nerves of pmn mutant mice, a model of motoneuron disease, causes disturbed microtubule dynamics. The disease is caused by a point mutation in the tubulin-specific chaperone E (Tbce) gene, leading to an exchange of the most C-terminal amino acid tryptophan to glycine. As a consequence, the TBCE protein becomes instable which then results in destabilization of axonal microtubules and defects in axonal transport, in particular in motoneurons. Depletion of neurofilament increases the number and regrowth of microtubules in pmn mutant motoneurons and restores axon elongation. This effect is mediated by interaction of neurofilament with the stathmin complex. Accumulating neurofilaments associate with stathmin in axons of pmn mutant motoneurons. Depletion of neurofilament by Nefl knockout increases Stat3-stathmin interaction and stabilizes the microtubules in pmn mutant motoneurons. Consequently, counteracting enhanced neurofilament expression improves axonal maintenance and prolongs survival of pmn mutant mice. We propose that this mechanism could also be relevant for other neurodegenerative diseases in which neurofilament accumulation and loss of microtubules are prominent features.
KW - Amyotrophic-lateral-sclerosis
KW - Transgenic mice
KW - Mouse model
KW - Alzheimers disease
KW - Neurofilament
KW - Progressive motor neuronopathy
KW - Axonal transport
KW - Intermediate filaments
KW - Motoneuron disease
KW - Lacking neurofilaments
KW - Missense mutation
KW - Axon degeneration
KW - Microtubules
KW - Stathmin
KW - Stat3
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-188234
VL - 132
IS - 1
ER -
TY - THES
A1 - Yadav, Preeti
T1 - Studying Neuronal Cytoskeleton Defects and Synaptic Defects in Mouse Model of Amyotrophic Lateral Sclerosis and Spinal Muscular Atrophy
T1 - Die Analyse des neuronalen Zytoskeletts und synaptischer Defekte im Mausmodel der Amyotrophen Lateralsklerose und der Spinalen Muskelatrophie
N2 - Amyotrophic lateral sclerosis and spinal muscular atrophy are the two most common motoneuron diseases. Both are characterized by destabilization of axon terminals, axon degeneration and alterations in neuronal cytoskeleton. Accumulation of neurofilaments has been observed in several neurodegenerative diseases but the mechanisms how elevated neurofilament levels destabilize axons are unknown so far. Here, I show that increased neurofilament expression in motor nerves of pmn mutant mice causes disturbed microtubule dynamics. Depletion of neurofilament by Nefl knockout increases the number and regrowth of microtubules in pmn mutant motoneurons and restores axon elongation. This effect is mediated by interaction of neurofilament with the stathmin complex. Depletion of neurofilament increases stathmin-Stat3 interaction and stabilizes the microtubules. Consequently, the axonal maintenance is improved and the pmn mutant mice survive longer. We propose that this mechanism could also be relevant for other neurodegenerative diseases in which neurofilament accumulation is a prominent feature.
Next, using Smn-/-;SMN2 mouse as a model, the molecular mechanism behind synapse loss in SMA is studied. SMA is characterized by degeneration of lower α-motoneurons in spinal cord; however, how reduction of ubiquitously expressed SMN leads to MN-specific degeneration remains unclear. SMN is involved in pre-mRNA splicing (Pellizzoni, Kataoka et al. 1998) and its deficiency in SMA affects the splicing machinery. Neuromuscular junction denervation precedes neurodegeneration in SMA. However, there is no evidence of a link between aberrant splicing of transcripts downstream of Smn and reduced presynaptic axon excitability observed in SMA. In this study, we observed that expression and splicing of Nrxn2, that encodes a presynaptic protein is affected in the SMA mouse and that Nrxn2 could be a candidate that relates aberrant splicing to synaptic motoneuron defects in SMA.
N2 - Die Amyotrophe Lateralsklerose und die spinale Muskelatrophie sind die beiden häufigsten Formen der Motoneuronerkrankungen. Sie sind charakterisiert durch eine Destabilisierung der Axonendigungen, durch Axondegeneration und durch Änderungen im neuronalen Zytoskelett. Eine Anhäufung von Neurofilamenten konnte in einigen neurodegenerativen Erkrankungen beobachtet werden. Der genaue Mechanismus, welcher zu einer Destabilisierung des Axons führt, ist bis heute jedoch unklar. Hiermit zeige ich, dass eine gesteigerte Expression von Neurofilamenten in motorischen Nerven von pmn mutierten Mäusen zu einer Störung der Mikrotubuli – Dynamik führt. Ein Neurofilamentabbau durch Nefl knockout steigert die Anzahl an neu wachsenden Mikrotubuli in pmn mutierten Motoneuronen und führt zu erneutem Axonwachstum. Dieser Effekt wird durch eine Interaktion zwischen dem Neurofilament und dem Stathmin Komplex vermittelt. Ein Abbau des Neurofilaments führt zu einer Erhöhung der Stathmin-Stat3 Interaktion und zu einer Stabilisierung der Mikrotubuli. Demzufolge ist die Versorgung der Axone verbessert und die pmn mutierten Mäuse überleben länger. Wir vermuten, dass dieser Mechanismus auch für andere neurodegenerative Erkrankungen, bei denen Neurofilamentanhäufung ein dominantes Merkmal ist, relevant sein könnte.
Des Weiteren studierte ich mit Hilfe des Smn-/-;SMN2 Mausmodels, den molekularen Mechanismus der sich hinter dem Synapsenverlust bei SMA verbirgt. SMA ist charakterisiert durch eine Degeneration der unteren -Motoneuronen im Rückenmark. Es ist jedoch unklar, wie ein Verlust des ubiquitär exprimierten SMN Proteins zu einer MN-spezifischen Degeneration führt. Smn ist involviert in den Prozess des pre-mRNA Splicing (Pellizzoni, Kataoka et al. 1998) und ein Verlust des Proteins führt zu einer Störung des Splicing. Eine Denervierung der motorischen Endplatte führt zu einer Neurodegeneration in SMA. Es gibt jedoch keinen Hinweis auf eine kausale Verbindung zwischen anomalem Splicen von stromabwärts gelegenen Transkripten des Smn und einer Reduktion präsynaptischer Axone, wie man es bei SMA beobachten kann. In dieser Studie konnten wir beobachten, dass Expression und Splicing von Nrxn2, welches für ein präsynaptisches Protein kodiert, in SMA Mäusen betroffen ist und dass Nrxn2 ein Kandidat sein könnte, der eine Verbindung zwischen Störungen im Splice Prozess und synaptischen Motoneuron-Defekten in der SMA herstellen könnte.
KW - Neurofilament
KW - Neurofilament
KW - Zellskelett
KW - Spinale Muskelatrophie
KW - Cytoskeleton
KW - Spinal muscular Atrophy
KW - Pmn mutant mouse
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-138093
ER -
TY - JOUR
A1 - Xu, Li
A1 - He, Jianzheng
A1 - Kaiser, Andrea
A1 - Gräber, Nikolas
A1 - Schläger, Laura
A1 - Ritze, Yvonne
A1 - Scholz, Henrike
T1 - A Single Pair of Serotonergic Neurons Counteracts Serotonergic Inhibition of Ethanol Attraction in Drosophila
JF - PLoS ONE
N2 - Attraction to ethanol is common in both flies and humans, but the neuromodulatory mechanisms underlying this innate attraction are not well understood. Here, we dissect the function of the key regulator of serotonin signaling—the serotonin transporter–in innate olfactory attraction to ethanol in Drosophila melanogaster. We generated a mutated version of the serotonin transporter that prolongs serotonin signaling in the synaptic cleft and is targeted via the Gal4 system to different sets of serotonergic neurons. We identified four serotonergic neurons that inhibit the olfactory attraction to ethanol and two additional neurons that counteract this inhibition by strengthening olfactory information. Our results reveal that compensation can occur on the circuit level and that serotonin has a bidirectional function in modulating the innate attraction to ethanol. Given the evolutionarily conserved nature of the serotonin transporter and serotonin, the bidirectional serotonergic mechanisms delineate a basic principle for how random behavior is switched into targeted approach behavior.
KW - attraction
KW - ethanol
KW - Drosophila melanogaster
KW - serotonin transporter
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166762
VL - 11
IS - 12
ER -
TY - JOUR
A1 - Wölfling, Mirko
A1 - Becker, Mira C.
A1 - Uhl, Britta
A1 - Traub, Anja
A1 - Fiedler, Konrad
T1 - How differences in the settling behaviour of moths (Lepidoptera) may contribute to sampling bias when using automated light traps
JF - European Journal of Entomology
N2 - Quantitative community-wide moth surveys frequently employ flight-interception traps equipped with UV-light emitting sources as attractants. It has long been known that moth species differ in their responsiveness to light traps. We studied how the settling behaviour of moths at a light trap may further contribute to sampling bias. We observed the behaviour of 1426 moths at a light tower. Moths were classified as either, settling and remaining still after arrival, or continually moving on the gauze for extended periods of time. Moths that did not move after settling may not end up in the sampling container of the light trap and therefore are under-represented in automated trap samples relative to their true proportions in the community. Our analyses revealed highly significant behavioural differences between moths that differed in body size. Small moths were more likely to remain stationary after settling. As a corollary, representatives of three taxa, which in Europe are predominantly small species (Nolidae, Geometridae: Eupitheciini, Erebidae: Lithosiini), usually settled down immediately, whereas most other moths remained active on or flying around the trap for some time. Moth behaviour was also modulated by ambient temperature. At high temperatures, they were less likely to settle down immediately, but this behavioural difference was most strongly apparent among medium-sized moths. These results indicate the likely extent of the sampling bias when analysing and interpreting automated light-trap samples. Furthermore, to control for temperature modulated sampling bias temperature should always be recorded when sampling moths using flight-interception traps.
KW - Lepidoptera
KW - moths
KW - biodiversity assessment
KW - sampling method
KW - light-trapping
KW - sampling bias
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-191154
VL - 113
ER -
TY - JOUR
A1 - Wächtler, Maria
A1 - Kübel, Joachim
A1 - Barthelmes, Kevin
A1 - Winter, Andreas
A1 - Schmiedel, Alexander
A1 - Pascher, Torbjörn
A1 - Lambert, Christoph
A1 - Schubert, Ulrich S.
A1 - Dietzek, Benjamin
T1 - Energy transfer and formation of long-lived \(^3\)MLCT states in multimetallic complexes with extended highly conjugated bis-terpyridyl ligands
JF - Physical Chemistry Chemical Physics
N2 - Multimetallic complexes with extended and highly conjugated bis-2,2':6',2''-terpyridyl bridging ligands, which present building blocks for coordination polymers, are investigated with respect to their ability to act as light-harvesting antennae. The investigated species combine Ru(II)- with Os(II)- and Fe(II)-terpyridyl chromophores, the latter acting as energy sinks. Due to the extended conjugated system the ligands are able to prolong the lifetime of the \(^3\)MLCT states compared to unsubstituted terpyridyl species by delocalization and energetic stabilization of the \(^3\)MLCT states. This concept is applied for the first time to Fe(II) terpyridyl species and results in an exceptionally long lifetime of 23 ps for the Fe(II) \(^3\)MLCT state. While partial energy (>80%) transfer is observed between the Ru(II) and Fe(II) centers with a time-constant of 15 ps, excitation energy is transferred completely from the Ru(II) to the Os(II) center within the first 200 fs after excitation.
KW - polypyridyl complexes
KW - bis-terpyridyl ligands
KW - multimetallic complexes
KW - metal-to-ligand charge transfer (MLCT)
KW - RU-(II) complexes
KW - Ru(II)–Fe(II)–Ru(II) complex
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-191041
VL - 18
IS - 4
ER -
TY - JOUR
A1 - Wunsch, Marie
A1 - Hohmann, Christopher
A1 - Milles, Bianca
A1 - Rostermund, Christina
A1 - Lehmann, Paul V.
A1 - Schroeter, Michael
A1 - Bayas, Antonios
A1 - Ulzheimer, Jochen
A1 - Mäurer, Mathias
A1 - Ergün, Süleyman
A1 - Kuerten, Stefanie
T1 - The Correlation between the Virus- and Brain Antigen-Specific B Cell Response in the Blood of Patients with Multiple Sclerosis
JF - Viruses
N2 - There is a largely divergent body of literature regarding the relationship between Epstein-Barr virus (EBV) infection and brain inflammation in multiple sclerosis (MS). Here, we tested MS patients during relapse (n = 11) and in remission (n = 19) in addition to n = 22 healthy controls to study the correlation between the EBV- and brain-specific B cell response in the blood by enzyme-linked immunospot (ELISPOT) and enzyme-linked immunosorbent assay (ELISA). Cytomegalovirus (CMV) was used as a control antigen tested in n = 16 MS patients during relapse and in n = 35 patients in remission. Over the course of the study, n = 16 patients were untreated, while n = 33 patients received immunomodulatory therapy. The data show that there was a moderate correlation between the frequencies of EBV- and brain-reactive B cells in MS patients in remission. In addition we could detect a correlation between the B cell response to EBV and disease activity. There was no evidence of an EBV reactivation. Interestingly, there was also a correlation between the frequencies of CMV- and brain-specific B cells in MS patients experiencing an acute relapse and an elevated B cell response to CMV was associated with higher disease activity. The trend remained when excluding seronegative subjects but was non-significant. These data underline that viral infections might impact the immunopathology of MS, but the exact link between the two entities remains subject of controversy.
KW - B cells
KW - CMV
KW - EBV
KW - ELISPOT
KW - MS
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146946
VL - 8
IS - 4
ER -
TY - JOUR
A1 - Wunsch, Kathrin
A1 - Pfister, Roland
A1 - Henning, Anne
A1 - Aschersleben, Gisa
A1 - Weigelt, Matthias
T1 - No Interrelation of Motor Planning and Executive Functions across Young Ages
JF - Frontiers in Psychology
N2 - The present study examined the developmental trajectories of motor planning and executive functioning in children. To this end, we tested 217 participants with three motor tasks, measuring anticipatory planning abilities (i.e., the bar-transport-task, the sword-rotation-task and the grasp-height-task), and three cognitive tasks, measuring executive functions (i.e., the Tower-of-Hanoi-task, the Mosaic-task, and the D2-attention-endurance-task). Children were aged between 3 and 10 years and were separated into age groups by 1-year bins, resulting in a total of eight groups of children and an additional group of adults. Results suggested (1) a positive developmental trajectory for each of the sub-tests, with better task performance as children get older; (2) that the performance in the separate tasks was not correlated across participants in the different age groups; and (3) that there was no relationship between performance in the motor tasks and in the cognitive tasks used in the present study when controlling for age. These results suggest that both, motor planning and executive functions are rather heterogeneous domains of cognitive functioning with fewer interdependencies than often suggested.
KW - anticipatory planning
KW - end-state comfort effect
KW - developmental disorders
KW - child development
KW - motor development
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165281
VL - 7
IS - 1031
ER -
TY - JOUR
A1 - Wolf, Karen
A1 - Braun, Attila
A1 - Haining, Elizabeth J.
A1 - Tseng, Yu-Lun
A1 - Kraft, Peter
A1 - Schuhmann, Michael K.
A1 - Gotru, Sanjeev K.
A1 - Chen, Wenchun
A1 - Hermanns, Heike M.
A1 - Stoll, Guido
A1 - Lesch, Klaus-Peter
A1 - Nieswandt, Bernhard
T1 - Partially Defective Store Operated Calcium Entry and Hem(ITAM) Signaling in Platelets of Serotonin Transporter Deficient Mice
JF - PLoS One
N2 - Background
Serotonin (5-hydroxytryptamin, 5-HT) is an indolamine platelet agonist, biochemically derived from tryptophan. 5-HT is secreted from the enterochromaffin cells into the gastrointestinal tract and blood. Blood 5-HT has been proposed to regulate hemostasis by acting as a vasoconstrictor and by triggering platelet signaling through 5-HT receptor 2A (5HTR2A). Although platelets do not synthetize 5-HT, they take 5-HT up from the blood and store it in their dense granules which are secreted upon platelet activation.
Objective
To identify the molecular composite of the 5-HT uptake system in platelets and elucidate the role of platelet released 5-HT in thrombosis and ischemic stroke. Methods: 5-HT transporter knockout mice (5Htt\(^{-/-}\)) were analyzed in different in vitro and in vivo assays and in a model of ischemic stroke.
Results
In 5Htt\(^{-/-}\) platelets, 5-HT uptake from the blood was completely abolished and agonist-induced Ca2+ influx through store operated Ca\(^{2+}\) entry (SOCE), integrin activation, degranulation and aggregation responses to glycoprotein VI (GPVI) and C-type lectin-like receptor 2 (CLEC-2) were reduced. These observed in vitro defects in 5Htt\(^{-/-}\) platelets could be normalized by the addition of exogenous 5-HT. Moreover, reduced 5-HT levels in the plasma, an increased bleeding time and the formation of unstable thrombi were observed ex vivo under flow and in vivo in the abdominal aorta and carotid artery of 5Htt\(^{-/-}\) mice. Surprisingly, in the transient middle cerebral artery occlusion (tMCAO) model of ischemic stroke 5Htt\(^{-/-}\) mice showed nearly normal infarct volume and the neurological outcome was comparable to control mice.
Conclusion
Although secreted platelet 5-HT does not appear to play a crucial role in the development of reperfusion injury after stroke, it is essential to amplify the second phase of platelet activation through SOCE and plays an important role in thrombus stabilization.
KW - platelets
KW - serotonin
KW - integrins
KW - blood flow
KW - collagens
KW - platelet activation
KW - platelet aggregation
KW - ischemic stroke
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146399
VL - 11
IS - 1
ER -
TY - JOUR
A1 - Wohlgemuth, Matthias
A1 - Mitric, Roland
T1 - Photochemical Chiral Symmetry Breaking in Alanine
JF - Journal of Physical Chemistry A
N2 - We introduce a general theoretical approach for the simulation of photochemical dynamics under the influence of circularly polarized light to explore the possibility of generating enantiomeric enrichment through polarized-light-selective photochemistry. The method is applied to the simulation of the photolysis of alanine, a prototype chiral amino acid. We show that a systematic enantiomeric enrichment can be obtained depending on the helicity of the circularly polarized light that induces the excited-state photochemistry of alanine. By analyzing the patterns of the photoinduced fragmentation of alanine we find an inducible enantiomeric enrichment up to 1.7%, which is also in good correspondence to the experimental findings. Our method is generally applicable to complex systems and might serve to systematically explore the photochemical origin of homochirality.
KW - circularly-polarized light
KW - amino-acids
KW - homochirality
KW - molecular dynamics
KW - dichroism
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158557
UR - https://pubs.acs.org/doi/10.1021/acs.jpca.6b07611
N1 - This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Physical Chemistry A, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acs.jpca.6b07611
VL - 45
IS - 120
ER -
TY - JOUR
A1 - Wittmann, Katharina
A1 - Sieber, Cornel
A1 - von Stengel, Simon
A1 - Kohl, Matthias
A1 - Freiberger, Ellen
A1 - Jakob, Franz
A1 - Lell, Michael
A1 - Engelke, Klaus
A1 - Kemmler, Wolfgang
T1 - Impact of whole body electromyostimulation on cardiometabolic risk factors in older women with sarcopenic obesity: the randomized controlled FORMOsA-sarcopenic obesity study
JF - Clinical Interventions in Aging
N2 - Background:
Sarcopenic obesity (SO) is characterized by a combination of low muscle and high fat mass with an additive negative effect of both conditions on cardiometabolic risk. The aim of the study was to determine the effect of whole-body electromyostimulation (WB-EMS) on the metabolic syndrome (MetS) in community-dwelling women aged ≥70 years with SO.
Methods:
The study was conducted in an ambulatory university setting. Seventy-five community-dwelling women aged ≥70 years with SO living in Northern Bavaria, Germany, were randomly allocated to either 6 months of WB-EMS application with (WB-EMS&P) or without (WB-EMS) dietary supplementation (150 kcal/day, 56% protein) or a non-training control group (CG). WB-EMS included one session of 20 min (85 Hz, 350 µs, 4 s of strain–4 s of rest) per week with moderate-to-high intensity. The primary study endpoint was the MetS Z-score with the components waist circumference (WC), mean arterial pressure (MAP), triglycerides, fasting plasma glucose, and high-density lipoprotein cholesterol (HDL-C); secondary study endpoints were changes in these determining variables.
Results:
MetS Z-score decreased in both groups; however, changes compared with the CG were significant (P=0.001) in the WB-EMS&P group only. On analyzing the components of the MetS, significant positive effects for both WB-EMS groups (P≤0.038) were identified for MAP, while the WB-EMS group significantly differed for WC (P=0.036), and the WB-EMS&P group significantly differed for HDL-C (P=0.006) from the CG. No significant differences were observed between the WB-EMS groups.
Conclusion:
The study clearly confirms the favorable effect of WB-EMS application on the MetS in community-dwelling women aged ≥70 years with SO. However, protein-enriched supplements did not increase effects of WB-EMS alone. In summary, we considered this novel technology an effective and safe method to prevent cardiometabolic risk factors and diseases in older women unable or unwilling to exercise conventionally.
KW - sarcopenia
KW - obesity
KW - whole-body electromyostimulation
KW - cardiovascular
KW - metabolic risk
KW - metabolic syndrome
KW - community-dwelling
KW - older people
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164930
VL - 11
ER -
TY - JOUR
A1 - Wilhelm, M.
A1 - Smetak, M.
A1 - Reimer, P.
A1 - Geissinger, E.
A1 - Ruediger, T.
A1 - Metzner, B.
A1 - Schmitz, N.
A1 - Engert, A.
A1 - Schaefer-Eckart, K.
A1 - Birkmann, J.
T1 - First-line therapy of peripheral T-cell lymphoma: extension and long-term follow-up of a study investigating the role of autologous stem cell transplantation
JF - Blood Cancer Journal
N2 - Current guidelines recommend consolidation with autologous stem cell transplantation (autoSCT) after induction chemotherapy for most patients with peripheral T-cell lymphoma (PTCL). This assumption is based on five prospective phase II studies, three of which included <50 patients with limited follow-up. Here we present the final analysis of the prospective German study. The treatment regimen consisted of four to six cycles of CHOP chemotherapy followed by mobilizing therapy and stem cell collection. Patients in complete remission (CR) or partial remission (PR) underwent myeloablative chemo(radio)therapy and autoSCT. From January 2001 to July 2010, 111 patients were enrolled in the study. The main subgroups were PTCL not specified (n=42) and angioimmunoblastic T-cell lymphoma (n=37). Seventy-five (68%) of the 111 patients received transplantation. The main reason for not receiving autoSCT was progressive disease. In an intent-to-treat analysis, the complete response rate after myeloablative therapy was 59%. The estimated 5-year overall survival, disease-free survival and progression-free survival rates were 44%, 54% and 39%, respectively. The results of this study confirm that upfront autoSCT can result in long-term remissions in patients with all major subtypes of PTCL and therefore should be part of first-line therapy whenever possible.
KW - Chemotherapy
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164506
VL - 6
ER -
TY - JOUR
A1 - Wildgruber, Moritz
A1 - Aschenbrenner, Teresa
A1 - Wendorff, Heiko
A1 - Czubba, Maria
A1 - Glinzer, Almut
A1 - Haller, Bernhard
A1 - Schiemann, Matthias
A1 - Zimmermann, Alexander
A1 - Berger, Hermann
A1 - Eckstein, Hans-Henning
A1 - Meier, Reinhard
A1 - Wohlgemuth, Walter A.
A1 - Libby, Peter
A1 - Zernecke, Alma
T1 - The "Intermediate" CD14\(^{++}\)CD16\(^{+}\) monocyte subset increases in severe peripheral artery disease in humans
JF - Scientific Reports
N2 - Monocytes are key players in atherosclerotic. Human monocytes display a considerable heterogeneity and at least three subsets can be distinguished. While the role of monocyte subset heterogeneity has already been well investigated in coronary artery disease (CAD), the knowledge about monocytes and their heterogeneity in peripheral artery occlusive disease (PAOD) still is limited. Therefore, we aimed to investigate monocyte subset heterogeneity in patients with PAOD. Peripheral blood was obtained from 143 patients suffering from PAOD (Rutherford stage I to VI) and three monocyte subsets were identified by flow cytometry: CD14\(^{++}\)CD16\(^{-}\) classical monocytes, CD14\(^{+}\)CD16\(^{++}\) non-classical monocytes and CD14\(^{++}\)CD16\(^{+}\) intermediate monocytes. Additionally the expression of distinct surface markers (CD106, CD162 and myeloperoxidase MPO) was analyzed. Proportions of CD14\(^{++}\)CD16\(^{+}\) intermediate monocyte levels were significantly increased in advanced stages of PAOD, while classical and non-classical monocytes displayed no such trend. Moreover, CD162 and MPO expression increased significantly in intermediate monocyte subsets in advanced disease stages. Likewise, increased CD162 and MPO expression was noted in CD14\(^{++}\)CD16\(^{-}\) classical monocytes. These data suggest substantial dynamics in monocyte subset distributions and phenotypes in different stages of PAOD, which can either serve as biomarkers or as potential therapeutic targets to decrease the inflammatory burden in advanced stages of atherosclerosis.
KW - peripheral artery occlusive disease
KW - monocyte subset
KW - humans
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167476
VL - 6
IS - 39483
ER -
TY - JOUR
A1 - Wieser, Matthias J.
A1 - Reicherts, Philipp
A1 - Juravle, Georgiana
A1 - von Leupoldt, Andreas
T1 - Attention mechanisms during predictable and unpredictable threat - a steady-state visual evoked potential approach
JF - NeuroImage
N2 - Fear is elicited by imminent threat and leads to phasic fear responses with selective attention, whereas anxiety is characterized by a sustained state of heightened vigilance due to uncertain danger. In the present study, we investigated attention mechanisms in fear and anxiety by adapting the NPU-threat test to measure steady-state visual evoked potentials (ssVEPs). We investigated ssVEPs across no aversive events (N), predictable aversive events (P), and unpredictable aversive events (U), signaled by four-object arrays (30 s). In addition, central cues were presented during all conditions but predictably signaled imminent threat only during the P condition. Importantly, cues and context events were flickered at different frequencies (15 Hz vs. 20 Hz) in order to disentangle respective electrocortical responses. The onset of the context elicited larger electrocortical responses for U compared to P context. Conversely, P cues elicited larger electrocortical responses compared to N cues. Interestingly, during the presence of the P cue, visuocortical processing of the concurrent context was also enhanced. The results support the notion of enhanced initial hypervigilance to unpredictable compared to predictable threat contexts, while predictable cues show electrocortical enhancement of the cues themselves but additionally a boost of context processing.
KW - Event-related potential
KW - Contextual fear
KW - Conditioning evidence
KW - Sustained attention
KW - Selective attention
KW - Aversive events
KW - Time-course
KW - Virtual-reality
KW - Anxiety
KW - Humans
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187365
VL - 139
ER -
TY - JOUR
A1 - Wiedenmann, J.
A1 - Bocquillon, E.
A1 - Deacon, R.S.
A1 - Hartinger, S.
A1 - Herrmann, O.
A1 - Klapwijk, T.M.
A1 - Maier, L.
A1 - Ames, C.
A1 - Brüne, C.
A1 - Gould, C.
A1 - Oiwa, A.
A1 - Ishibashi, K.
A1 - Tarucha, S.
A1 - Buhmann, H.
A1 - Molenkamp, L.W.
T1 - 4π-periodic Josephson supercurrent in HgTe-based topological Josephson junctions
JF - Nature Communications
N2 - The Josephson effect describes the generic appearance of a supercurrent in a weak link between two superconductors. Its exact physical nature deeply influences the properties of the supercurrent. In recent years, considerable efforts have focused on the coupling of superconductors to the surface states of a three-dimensional topological insulator. In such a material, an unconventional induced p-wave superconductivity should occur, with a doublet of topologically protected gapless Andreev bound states, whose energies vary 4π-periodically with the superconducting phase difference across the junction. In this article, we report the observation of an anomalous response to rf irradiation in a Josephson junction made of a HgTe weak link. The response is understood as due to a 4π-periodic contribution to the supercurrent, and its amplitude is compatible with the expected contribution of a gapless Andreev doublet. Our work opens the way to more elaborate experiments to investigate the induced superconductivity in a three-dimensional insulator.
KW - Josephson effect
KW - supercurrent
KW - superconductors
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175353
VL - 7
ER -
TY - THES
A1 - Wiebusch, Dennis
T1 - Reusability for Intelligent Realtime Interactive Systems
T1 - Wiederverwendbarkeit für Intelligente Echtzeit-interaktive Systeme
N2 - Software frameworks for Realtime Interactive Systems (RIS), e.g., in the areas of Virtual, Augmented, and Mixed Reality (VR, AR, and MR) or computer games, facilitate a multitude of functionalities by coupling diverse software modules. In this context, no uniform methodology for coupling these modules does exist; instead various purpose-built solutions have been proposed. As a consequence, important software qualities, such as maintainability, reusability, and adaptability, are impeded.
Many modern systems provide additional support for the integration of Artificial Intelligence (AI) methods to create so called intelligent virtual environments. These methods exacerbate the above-mentioned problem of coupling software modules in the thus created Intelligent Realtime Interactive Systems (IRIS) even more. This, on the one hand, is due to the commonly applied specialized data structures and asynchronous execution schemes, and the requirement for high consistency regarding content-wise coupled but functionally decoupled forms of data representation on the other.
This work proposes an approach to decoupling software modules in IRIS, which is based on the abstraction of architecture elements using a semantic Knowledge Representation Layer (KRL). The layer facilitates decoupling the required modules, provides a means for ensuring interface compatibility and consistency, and in the end constitutes an interface for symbolic AI methods.
N2 - Software Frameworks zur Entwicklung Echtzeit-interaktiver Systeme (engl. Realtime Interactive Systems, RIS), z.B. mit Anwendungen in der Virtual, Augmented und Mixed Reality (VR, AR und MR) sowie in Computerspielen, integrieren vielfältige Funktionalitäten durch die Kopplung verschiedener Softwaremodule. Eine einheitliche Methodik einer Kopplung in diesen Systemen besteht dabei nicht, stattdessen existieren mannigfaltige individuelle Lösungen. Als Resultat sinken wichtige Softwarequalitätsfaktoren wie Wartbarkeit, Wiederverwendbarkeit und Anpassbarkeit.
Viele moderne Systeme setzen zusätzlich unterschiedliche Methoden der Künstlichen Intelligenz (KI) ein, um so intelligente virtuelle Umgebungen zu generieren. Diese KI-Methoden verschärfen in solchen Intelligenten Echtzeit-interaktiven Systemen (engl. Intelligent Realtime Interactive Systems, IRIS) das eingangs genannte Kopplungsproblem signifikant durch ihre spezialisierten Datenstrukturen und häufig asynchronen Prozessflüssen bei gleichzeitig hohen Konsistenzanforderungen bzgl. inhaltlich assoziierter, aber funktional entkoppelter Datenrepräsentationen in anderen Modulen.
Die vorliegende Arbeit beschreibt einen Lösungsansatz für das Entkopplungsproblem mittels Abstraktion maßgeblicher Softwarearchitekturelemente basierend auf einer erweiterbaren semantischen Wissensrepräsentationsschicht. Diese semantische Abstraktionsschicht erlaubt die Entkopplung benötigter Module, ermöglicht eine automatische Überprüfung von Schnittstellenkompatibiltät und Konsistenz und stellt darüber hinaus eine generische Schnittstelle zu symbolischen KI-Methoden bereit.
KW - Virtuelle Realität
KW - Ontologie
KW - Wissensrepräsentation
KW - Echtzeitsystem
KW - Framework
KW - Intelligent Realtime Interactive System
KW - Virtual Reality
KW - Knowledge Representation Layer
KW - Intelligent Virtual Environment
KW - Semantic Entity Model
KW - Erweiterte Realität
KW - Softwarewiederverwendung
KW - Modul
KW - Software Engineering
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-121869
SN - 978-3-95826-040-5 (print)
SN - 978-3-95826-041-2 (online)
N1 - Parallel erschienen als Druckausg. in Würzburg University Press, ISBN 978-3-95826-040-5, 34,90 EUR
PB - Würzburg University Press
CY - Würzburg
ER -
TY - JOUR
A1 - Widmann, Annekathrin
A1 - Artinger, Marc
A1 - Biesinger, Lukas
A1 - Boepple, Kathrin
A1 - Peters, Christina
A1 - Schlechter, Jana
A1 - Selcho, Mareike
A1 - Thum, Andreas S.
T1 - Genetic Dissection of Aversive Associative Olfactory Learning and Memory in Drosophila Larvae
JF - PLoS Genetics
N2 - Memory formation is a highly complex and dynamic process. It consists of different phases, which depend on various neuronal and molecular mechanisms. In adult Drosophila it was shown that memory formation after aversive Pavlovian conditioning includes—besides other forms—a labile short-term component that consolidates within hours to a longer-lasting memory. Accordingly, memory formation requires the timely controlled action of different neuronal circuits, neurotransmitters, neuromodulators and molecules that were initially identified by classical forward genetic approaches. Compared to adult Drosophila, memory formation was only sporadically analyzed at its larval stage. Here we deconstruct the larval mnemonic organization after aversive olfactory conditioning. We show that after odor-high salt conditioning larvae form two parallel memory phases; a short lasting component that depends on cyclic adenosine 3’5’-monophosphate (cAMP) signaling and synapsin gene function. In addition, we show for the first time for Drosophila larvae an anesthesia resistant component, which relies on radish and bruchpilot gene function, protein kinase C activity, requires presynaptic output of mushroom body Kenyon cells and dopamine function. Given the numerical simplicity of the larval nervous system this work offers a unique prospect for studying memory formation of defined specifications, at full-brain scope with single-cell, and single-synapse resolution.
KW - genetic dissection
KW - Drosophila
KW - memory formation
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166672
VL - 12
IS - 10
ER -
TY - JOUR
A1 - White, P. Lewis
A1 - Wiederhold, Nathan P.
A1 - Loeffler, Juergen
A1 - Najvar, Laura K.
A1 - Melchers, Willem
A1 - Herrera, Monica
A1 - Bretagne, Stephane
A1 - Wickes, Brian
A1 - Kirkpatrick, William R.
A1 - Barnes, Rosemary A.
A1 - Donnelly, J. Peter
A1 - Patterson, Thomas F.
T1 - Comparison of nonculture blood-based tests for diagnosing invasive aspergillosis in an animal model
JF - Journal of Clinical Microbiology
N2 - The European Aspergillus PCR Initiative (EAPCRI) has provided recommendations for the PCR testing of whole blood (WB) and serum/plasma. It is important to test these recommended protocols on nonsimulated "in vivo" specimens before full clinical evaluation. The testing of an animal model of invasive aspergillosis (IA) overcomes the low incidence of disease and provides experimental design and control that is not possible in the clinical setting. Inadequate performance of the recommended protocols at this stage would require reassessment of methods before clinical trials are performed and utility assessed. The manuscript describes the performance of EAPCRI protocols in an animal model of invasive aspergillosis. Blood samples taken from a guinea pig model of IA were used for WB and serum PCR. Galactomannan and beta-D-glucan detection were evaluated, with particular focus on the timing of positivity and on the interpretation of combination testing. The overall sensitivities for WB PCR, serum PCR, galactomannan, and beta-D-glucan were 73%, 65%, 68%, and 46%, respectively. The corresponding specificities were 92%, 79%, 80%, and 100%, respectively. PCR provided the earliest indicator of IA, and increasing galactomannan and beta-D-glucan values were indicators of disease progression. The combination of WB PCR with galactomannan and beta-D-glucan proved optimal (area under the curve AUC], 0.95), and IA was confidently diagnosed or excluded. The EAPRCI-recommended PCR protocols provide performance comparable to commercial antigen tests, and clinical trials are warranted. By combining multiple tests, IA can be excluded or confirmed, highlighting the need for a combined diagnostic strategy. However, this approach must be balanced against the practicality and cost of using multiple tests.
KW - high-risk hematology
KW - Guinea pig model
KW - real-time PCR
KW - fungal disease
KW - galactomannan
KW - pulmonary aspergillosis
KW - amphotericin B
KW - Aspergillus fumigatus
KW - beta-D-glucan
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189674
VL - 54
IS - 4
ER -
TY - JOUR
A1 - Wheeler, Nicole E.
A1 - Barquist, Lars
A1 - Kingsley, Robert A.
A1 - Gardner, Paul P.
T1 - A profile-based method for identifying functional divergence of orthologous genes in bacterial genomes
JF - Bioinformatics
N2 - Motivation:
Next generation sequencing technologies have provided us with a wealth of information on genetic variation, but predi cting the functional significance of this variation is a difficult task. While many comparative genomics studies have focused on gene flux and large scale changes, relatively little attention has been paid to quantifying the effects of single nucleotide polymorphisms and indels on protein function, particularly in bacterial genomics.
Results:
We present a hidden Markov model based approach we call delta-bitscore (DBS) for identifying orthologous proteins that have diverged at the amino acid sequence level in a way that is likely to impact biological function. We benchmark this approach with several widely used datasets and apply it to a proof-of-concept study of orthologous proteomes in an investigation of host adaptation in Salmonella enterica. We highlight the value of the method in identifying functional divergence of genes, and suggest that this tool may be a better approach than the commonly used dN/dS metric for identifying functionally significant genetic changes occurring in recently diverged organisms.
KW - Host adaptation
KW - Salmonella-enteritidis
KW - Sequence identity
KW - Rapid evolution
KW - Variants
KW - Cystic-fibriosis
KW - Strains
KW - Pathogenicity
KW - Typhimurium
KW - Yersinia
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-186502
VL - 32
IS - 23
ER -
TY - JOUR
A1 - Westermaier, Thomas
A1 - Linsenmann, Thomas
A1 - Homola, György A.
A1 - Loehr, Mario
A1 - Stetter, Christian
A1 - Willner, Nadine
A1 - Ernestus, Ralf-Ingo
A1 - Soymosi, Laszlo
A1 - Vince, Giles H.
T1 - 3D rotational fluoroscopy for intraoperative clip control in patients with intracranial aneurysms – assessment of feasibility and image quality
JF - BMC Medical Imaging
N2 - Background
Mobile 3D fluoroscopes have become increasingly available in neurosurgical operating rooms. In this series, the image quality and value of intraoperative 3D fluoroscopy with intravenous contrast agent for the evaluation of aneurysm occlusion and vessel patency after clip placement was assessed in patients who underwent surgery for intracranial aneurysms.
Materials and methods
Twelve patients were included in this retrospective analysis. Prior to surgery, a 360° rotational fluoroscopy scan was performed without contrast agent followed by another scan with 50 ml of intravenous iodine contrast agent. The image files of both scans were transferred to an Apple PowerMac® workstation, subtracted and reconstructed using OsiriX® free software. The procedure was repeated after clip placement. Both image sets were compared for assessment of aneurysm occlusion and vessel patency.
Results
Image acquisition and contrast administration caused no adverse effects. Image quality was sufficient to follow the patency of the vessels distal to the clip. Metal artifacts reduce the assessability of the immediate vicinity of the clip. Precise image subtraction and post-processing can reduce metal artifacts and make the clip-site assessable and depict larger neck-remnants.
Conclusion
This technique quickly supplies images at adequate quality to evaluate distal vessel patency after aneurysm clipping. Significant aneurysm remnants may be depicted as well. As it does not require visual control of all vessels that are supposed to be evaluated intraoperatively, this technique may be complementary to other intraoperative tools like indocyanine green videoangiography and micro-Doppler, especially for the assessment of larger aneurysms. At the momentary state of this technology, it cannot replace postoperative conventional angiography. However, 3D fluoroscopy and image post-processing are young technologies. Further technical developments are likely to result in improved image quality.
KW - aneurysm surgery
KW - clip control
KW - angiography
KW - 3D fluoroscopy
KW - image quality
KW - intraoperative
KW - vessel patency
KW - contrast
KW - post-processing
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146381
VL - 16
IS - 30
ER -
TY - JOUR
A1 - Werner, Rudolf A.
A1 - Beykan, Seval
A1 - Higuchi, Takahiro
A1 - Lückerath, Katharina
A1 - Weich, Alexander
A1 - Scheurlen, Michael
A1 - Bluemel, Christina
A1 - Herrmann, Ken
A1 - Buck, Andreas K.
A1 - Lassmann, Michael
A1 - Lapa, Constantin
A1 - Hänscheid, Heribert
T1 - The impact of \(^{177}\)Lu-octreotide therapy on \(^{99m}\)Tc-MAG3 clearance is not predictive for late nephropathy
JF - Oncotarget
N2 - Peptide Receptor Radionuclide Therapy (PRRT) for the treatment of neuroendocrine tumors may lead to kidney deterioration. This study aimed to evaluate the suitability of \(^{99m}\)Tc-mercaptoacetyltriglycine (\(^{99m}\)Tc-MAG3) clearance for the early detection of PRRT-induced changes on tubular extraction (TE). TE rate (TER) was measured prior to 128 PRRT cycles (7.6±0.4 GBq \(^{177}\)Lu-octreotate/octreotide each) in 32 patients. TER reduction during PRRT was corrected for age-related decrease and analyzed for the potential to predict loss of glomerular filtration (GF). The GF rate (GFR) as measure for renal function was derived from serum creatinine. The mean TER was 234 ± 53 ml/min/1.73 m² before PRRT (baseline) and 221 ± 45 ml/min/1.73 m² after a median follow-up of 370 days. The age-corrected decrease (mean: -3%, range: -27% to +19%) did not reach significance (p=0.09) but significantly correlated with the baseline TER (Spearman p=-0.62, p<0.001). Patients with low baseline TER showed an improved TER after PRRT, high decreases were only observed in individuals with high baseline TER. Pre-therapeutic TER data were inferior to plasma creatinine-derived GFR estimates in predicting late nephropathy. TER assessed by \(^{99m}\)Tc-MAG3clearance prior to and during PRRT is not suitable as early predictor of renal injury and an increased risk for late nephropathy.
KW - renal scintigraphy
KW - neuroendocrine tumor
KW - 177Lu
KW - MAG3
KW - PRRT
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177318
VL - 7
IS - 27
ER -
TY - JOUR
A1 - Werner, R. A.
A1 - Lückerath, K.
A1 - Schmid, J. S.
A1 - Higuchi, T.
A1 - Kreissl, M. C.
A1 - Grelle, I.
A1 - Reiners, C.
A1 - Buck, A. K.
A1 - Lapa, C.
T1 - Thyroglobulin fluctuations in patients with iodine-refractory differentiated thyroid carcinoma on lenvatinib treatment – initial experience
JF - Scientific Reports
N2 - Tyrosine kinase inhibitors (TKI) have shown clinical effectiveness in iodine-refractory differentiated thyroid cancer (DTC). The corresponding role of serum thyroglobulin (Tg) in iodine-refractory DTC has not been investigated yet. 9 patients (3 female, 61 ± 8y) with progressive iodine-refractory DTC starting on lenvatinib were considered. Tumor restaging was performed every 2–3 months including contrast-enhanced computed tomography (CT, RECIST 1.1). Serum Tg was measured and compared to imaging findings. After treatment initiation, serum Tg levels dropped in all patients with a median reduction of 86.2%. During long-term follow-up (median, 25.2 months), fluctuations in Tg could be observed in 8/9 subjects. According to RECIST, 6/9 subjects achieved a partial response or stable disease with the remaining 3/9 experiencing progressive disease (2/3 with Tg levels rising above baseline). All of the patients with disease progression presented with a preceding continuous rise in serum Tg, whereas tumor marker oscillations in the subjects with controlled disease were only intermittent. Initiation of lenvatinib in iodine-refractory DTC patients is associated with a significant reduction in serum Tg levels as a marker of treatment response. In the course of treatment, transient Tg oscillations are a frequent phenomenon that may not necessarily reflect morphologic tumor progression.
KW - Thyroid cancer
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147407
VL - 6
ER -
TY - JOUR
A1 - Werner, Franziska
A1 - Kojonazarov, Baktybek
A1 - Gaßner, Birgit
A1 - Abeßer, Marco
A1 - Schuh, Kai
A1 - Völker, Katharina
A1 - Baba, Hideo A.
A1 - Dahal, Bhola K.
A1 - Schermuly, Ralph T.
A1 - Kuhn, Michaela
T1 - Endothelial actions of atrial natriuretic peptide prevent pulmonary hypertension in mice
JF - Basic Research in Cardiology
N2 - The cardiac hormone atrial natriuretic peptide (ANP) regulates systemic and pulmonary arterial blood pressure by activation of its cyclic GMP-producing guanylyl cyclase-A (GC-A) receptor. In the lung, these hypotensive effects were mainly attributed to smooth muscle-mediated vasodilatation. It is unknown whether pulmonary endothelial cells participate in the homeostatic actions of ANP. Therefore, we analyzed GC-A/cGMP signalling in lung endothelial cells and the cause and functional impact of lung endothelial GC-A dysfunction. Western blot and cGMP determinations showed that cultured human and murine pulmonary endothelial cells exhibit prominent GC-A expression and activity which were markedly blunted by hypoxia, a condition known to trigger pulmonary hypertension (PH). To elucidate the consequences of impaired endothelial ANP signalling, we studied mice with genetic endothelial cell-restricted ablation of the GC-A receptor (EC GC-A KO). Notably, EC GC-A KO mice exhibit PH already under resting, normoxic conditions, with enhanced muscularization of small arteries and perivascular infiltration of inflammatory cells. These alterations were aggravated on exposure of mice to chronic hypoxia. Lung endothelial GC-A dysfunction was associated with enhanced expression of angiotensin converting enzyme (ACE) and increased pulmonary levels of Angiotensin II. Angiotensin II/AT(1)-blockade with losartan reversed pulmonary vascular remodelling and perivascular inflammation of EC GC-A KO mice, and prevented their increment by chronic hypoxia. This experimental study indicates that endothelial effects of ANP are critical to prevent pulmonary vascular remodelling and PH. Chronic endothelial ANP/GC-A dysfunction, e.g. provoked by hypoxia, is associated with activation of the ACE-angiotensin pathway in the lung and PH.
KW - Atrial natriuretic peptide
KW - Endothelium
KW - Guanylyl cyclase-A
KW - Cyclic GMP
KW - Pulmonary hypertension
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-190664
VL - 111
IS - 2
ER -
TY - JOUR
A1 - Wente, Sarah
A1 - Schröder, Simone
A1 - Buckard, Johannes
A1 - Büttel, Hans-Martin
A1 - von Deimling, Florian
A1 - Diener, Wilfried
A1 - Häussler, Martin
A1 - Hübschle, Susanne
A1 - Kinder, Silvia
A1 - Kurlemann, Gerhard
A1 - Kretzschmar, Christoph
A1 - Lingen, Michael
A1 - Maroske, Wiebke
A1 - Mundt, Dirk
A1 - Sánchez-Albisua, Iciar
A1 - Seeger, Jürgen
A1 - Toelle, Sandra P.
A1 - Boltshauser, Eugen
A1 - Brockmann, Knut
T1 - Nosological delineation of congenital ocular motor apraxia type Cogan: an observational study
JF - Orphanet Journal of Rare Diseases
N2 - Background
The nosological assignment of congenital ocular motor apraxia type Cogan (COMA) is still controversial. While regarded as a distinct entity by some authorities including the Online Mendelian Inheritance in Man catalog of genetic disorders, others consider COMA merely a clinical symptom.
Methods
We performed a retrospective multicenter data collection study with re-evaluation of clinical and neuroimaging data of 21 previously unreported patients (8 female, 13 male, ages ranging from 2 to 24 years) diagnosed as having COMA.
Results
Ocular motor apraxia (OMA) was recognized during the first year of life and confined to horizontal pursuit in all patients. OMA attenuated over the years in most cases, regressed completely in two siblings, and persisted unimproved in one individual. Accompanying clinical features included early onset ataxia in most patients and cognitive impairment with learning disability (n = 6) or intellectual disability (n = 4). Re-evaluation of MRI data sets revealed a hitherto unrecognized molar tooth sign diagnostic for Joubert syndrome in 11 patients, neuroimaging features of Poretti-Boltshauser syndrome in one case and cerebral malformation suspicious of a tubulinopathy in another subject. In the remainder, MRI showed vermian hypo-/dysplasia in 4 and no abnormalities in another 4 patients. There was a strong trend to more severe cognitive impairment in patients with Joubert syndrome compared to those with inconclusive MRI, but otherwise no significant difference in clinical phenotypes between these two groups.
Conclusions
Systematical renewed analysis of neuroimaging data resulted in a diagnostic reappraisal in the majority of patients with early-onset OMA in the cohort reported here. This finding poses a further challenge to the notion of COMA constituting a separate entity and underlines the need for an expert assessment of neuroimaging in children with COMA, especially if they show cognitive impairment.
KW - congenital ocular motor apraxia
KW - molar tooth sign
KW - Joubert syndrome
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166534
VL - 11
IS - 104
ER -
TY - JOUR
A1 - Weisschuh, Nicole
A1 - Mayer, Anja K.
A1 - Strom, Tim M.
A1 - Kohl, Susanne
A1 - Glöckle, Nicola
A1 - Schubach, Max
A1 - Andreasson, Sten
A1 - Bernd, Antje
A1 - Birch, David G.
A1 - Hamel, Christian P.
A1 - Heckenlively, John R.
A1 - Jacobson, Samuel G.
A1 - Kamme, Christina
A1 - Kellner, Ulrich
A1 - Kunstmann, Erdmute
A1 - Maffei, Pietro
A1 - Reiff, Charlotte M.
A1 - Rohrschneider, Klaus
A1 - Rosenberg, Thomas
A1 - Rudolph, Günther
A1 - Vámos, Rita
A1 - Varsányi, Balázs
A1 - Weleber, Richard G.
A1 - Wissinger, Bernd
T1 - Mutation Detection in Patients with Retinal Dystrophies Using Targeted Next Generation Sequencing
JF - PLoS ONE
N2 - Retinal dystrophies (RD) constitute a group of blinding diseases that are characterized by clinical variability and pronounced genetic heterogeneity. The different nonsyndromic and syndromic forms of RD can be attributed to mutations in more than 200 genes. Consequently, next generation sequencing (NGS) technologies are among the most promising approaches to identify mutations in RD. We screened a large cohort of patients comprising 89 independent cases and families with various subforms of RD applying different NGS platforms. While mutation screening in 50 cases was performed using a RD gene capture panel, 47 cases were analyzed using whole exome sequencing. One family was analyzed using whole genome sequencing. A detection rate of 61% was achieved including mutations in 34 known and two novel RD genes. A total of 69 distinct mutations were identified, including 39 novel mutations. Notably, genetic findings in several families were not consistent with the initial clinical diagnosis. Clinical reassessment resulted in refinement of the clinical diagnosis in some of these families and confirmed the broad clinical spectrum associated with mutations in RD genes.
KW - mutation detection
KW - retinal dystrophies
KW - next generation sequencing
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167398
VL - 11
IS - 1
ER -
TY - JOUR
A1 - Weismann, Dirk
A1 - Schneider, Andreas
A1 - Höybye, Charlotte
T1 - Clinical aspects of symptomatic hyponatremia
JF - Endocrine Connections
N2 - Hyponatremia (HN) is a common condition, with a large number of etiologies and a complicated treatment. Although chronic HN has been shown to be a predictor of poor outcome, sodium-increasing treatments in chronic stable and asymptomatic HN have not proven to increase life expectancy. For symptomatic HN, in contrast, the necessity for urgent treatment has broadly been accepted to avoid the development of fatal cerebral edema. On the other hand, a too rapid increase of serum sodium in chronic HN may result in cerebral damage due to osmotic demyelinisation. Recently, administration of hypertonic saline bolus has been recommended as first-line treatment in patients with moderate-to-severe symptomatic HN. This approach is easy to memorize and holds the potential to greatly facilitate the initial treatment of symptomatic HN. First-line treatment of chronic HN is fluid restriction and if ineffective treatment with tolvaptan or in some patients other agents should be considered. A number of recommendations and guidelines have been published on HN. In the present review, the management of patients with HN in relation to everyday clinical practice is summarized with focus on the acute management.
KW - hyponatremia
KW - clinical
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-162936
VL - 5
IS - 5
ER -
TY - JOUR
A1 - Weigand, Annika
A1 - Boos, Anja M.
A1 - Tasbihi, Kereshmeh
A1 - Beier, Justus P.
A1 - Dalton, Paul D.
A1 - Schrauder, Michael
A1 - Horch, Raymund E.
A1 - Beckmann, Matthias W.
A1 - Strissel, Pamela L.
A1 - Strick, Reiner
T1 - Selective isolation and characterization of primary cells from normal breast and tumors reveal plasticity of adipose derived stem cells
JF - Breast Cancer Research
N2 - Background
There is a need to establish more cell lines from breast tumors in contrast to immortalized cell lines from metastatic effusions in order to represent the primary tumor and not principally metastatic biology of breast cancer. This investigation describes the simultaneous isolation, characterization, growth and function of primary mammary epithelial cells (MEC), mesenchymal cells (MES) and adipose derived stem cells (ADSC) from four normal breasts, one inflammatory and one triple-negative ductal breast tumors.
Methods
A total of 17 cell lines were established and gene expression was analyzed for MEC and MES (n = 42) and ADSC (n = 48) and MUC1, pan-KRT, CD90 and GATA-3 by immunofluorescence. DNA fingerprinting to track cell line identity was performed between original primary tissues and isolates. Functional studies included ADSC differentiation, tumor MES and MEC invasion co-cultured with ADSC-conditioned media (CM) and MES adhesion and growth on 3D-printed scaffolds.
Results
Comparative analysis showed higher gene expression of EPCAM, CD49f, CDH1 and KRTs for normal MEC lines; MES lines e.g. Vimentin, CD10, ACTA2 and MMP9; and ADSC lines e.g. CD105, CD90, CDH2 and CDH11. Compared to the mean of all four normal breast cell lines, both breast tumor cell lines demonstrated significantly lower ADSC marker gene expression, but higher expression of mesenchymal and invasion gene markers like SNAI1 and MMP2. When compared with four normal ADSC differentiated lineages, both tumor ADSC showed impaired osteogenic and chondrogenic but enhanced adipogenic differentiation and endothelial-like structures, possibly due to high PDGFRB and CD34. Addressing a functional role for overproduction of adipocytes, we initiated 3D-invasion studies including different cell types from the same patient. CM from ADSC differentiating into adipocytes induced tumor MEC 3D-invasion via EMT and amoeboid phenotypes. Normal MES breast cells adhered and proliferated on 3D-printed scaffolds containing 20 fibers, but not on 2.5D-printed scaffolds with single fiber layers, important for tissue engineering.
Conclusion
Expression analyses confirmed successful simultaneous cell isolations of three different phenotypes from normal and tumor primary breast tissues. Our cell culture studies support that breast-tumor environment differentially regulates tumor ADSC plasticity as well as cell invasion and demonstrates applications for regenerative medicine.
KW - Normal breast
KW - Breast cancer
KW - Stem cells plasticity
KW - Primary cell lines
KW - Tissue engineering
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164759
VL - 18
IS - 32
ER -
TY - JOUR
A1 - Weidner, Christopher
A1 - Rousseau, Morten
A1 - Plauth, Annabell
A1 - Wowro, Sylvia J.
A1 - Fischer, Cornelius
A1 - Abdel-Aziz, Heba
A1 - Sauer, Sascha
T1 - Iberis amara Extract Induces Intracellular Formation of Reactive Oxygen Species and Inhibits Colon Cancer
JF - PLoS ONE
N2 - Massively increasing global incidences of colorectal cancer require efficient treatment and prevention strategies. Here, we report unexpected anticancerogenic effects of hydroethanolic Iberis amara extract (IAE), which is known as a widely used phytomedical product for treating gastrointestinal complaints. IAE significantly inhibited the proliferation of HT-29 and T84 colon carcinoma cells with an inhibitory concentration (IC\(_{50}\)) of 6 and 9 μg/ml, respectively, and further generated inhibitory effects in PC-3 prostate and MCF7 breast cancer cells. Inhibition of proliferation in HT-29 cells was associated with a G2/M phase cell cycle arrest including reduced expression of various regulatory marker proteins. Notably, in HT-29 cells IAE further induced apoptosis by intracellular formation of reactive oxygen species (ROS). Consistent with predictions derived from our in vitro experiments, bidaily oral gavage of 50 mg/kg of IAE over 4 weeks resulted in significant inhibition of tumor growth in a mouse HT-29 tumor xenograft model. Taken together, Iberis amara extracts could become useful alternatives for preventing and treating the progression of colon cancer.
KW - iberis amara extract
KW - colorectal cancer
KW - treatment
KW - prevention
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167044
VL - 11
IS - 4
ER -
TY - JOUR
A1 - Weidemann, Frank
A1 - Maier, Sebastian K. G.
A1 - Störk, Stefan
A1 - Brunner, Thomas
A1 - Liu, Dan
A1 - Hu, Kai
A1 - Seydelmann, Nora
A1 - Schneider, Andreas
A1 - Becher, Jan
A1 - Canan-Kühl, Sima
A1 - Blaschke, Daniela
A1 - Bijnens, Bart
A1 - Ertl, Georg
A1 - Wanner, Christoph
A1 - Nordbeck, Peter
T1 - Usefulness of an implantable loop recorder to detect clinically relevant arrhythmias in patients with advanced fabry cardiomyopathy
JF - The American Journal of Cardiology
N2 - Patients with genetic cardiomyopathy that involves myocardial hypertrophy often develop clinically relevant arrhythmias that increase the risk of sudden death. Consequently, guidelines for medical device therapy were established for hypertrophic cardiomyopathy, but not for conditions with only anecdotal evidence of arrhythmias, like Fabry cardiomyopathy. Patients with Fabry cardiomyopathy progressively develop myocardial fibrosis, and sudden cardiac death occurs regularly. Because 24-hour Holier electrocardiograms (ECGs) might not detect clinically important arrhythmias, we tested an implanted loop recorder for continuous heart rhythm surveillance and determined its impact on therapy. This prospective study included 16 patients (12 men) with advanced Fabry cardiomyopathy, relevant hypertrophy, and replacement fibrosis in "loco typico." No patients previously exhibited clinically relevant arrhythmias on Holier ECGs. Patients received an implantable loop recorder and were prospectively followed with telemedicine for a median of 1.2 years (range 0.3 to 2.0 years). The primary end point was a clinically meaningful event, which required a therapy change, captured with the loop recorder. Patients submitted data regularly (14 +/- 11 times per month). During follow-up, 21 events were detected (including 4 asystole, i.e., ECG pauses >= 3 seconds) and 7 bradycardia events; 5 episodes of intermittent atrial fibrillation (>3 minutes) and 5 episodes of ventricular tachycardia (3 sustained and 2 nonsustained). Subsequently, as defined in the primary end point, 15 events leaded to a change of therapy. These patients required therapy with a pacemaker or cardioverter defibrillator implantation and/or anticoagulation therapy for atrial fibrillation. In conclusion, clinically relevant arrhythmias that require further device and/or medical therapy are often missed with Holier ECGs in patients with advanced stage Fabry cardiomyopathy, but they can be detected by telemonitoring with an implantable loop recorder.
KW - Cardiovascular magnetic-resonance
KW - Coronary artery disease
KW - Ventricular-arrhythmias
KW - Task force
KW - Management
KW - Enzyme replacement therapy
KW - Hypertrophic cardiomyopathy
KW - Myocardial fibrosis
KW - Guidelines
KW - Manifestation
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-188093
VL - 118
IS - 2
ER -
TY - THES
A1 - Weber, Stefan
T1 - Simulation Studies on the New Small Wheel Shielding of the ATLAS Experiment and Design and Construction of a Test Facility for Gaseous Detectors
T1 - Simulationsstudien zur New Small Wheel Abschirmung des ATLAS Experiments und Entwurf und Konstruktion eines Teststandes für Gasdetektoren
N2 - In this thesis two main projects are presented, both aiming at the overall goal
of particle detector development. In the first part of the thesis detailed shielding
studies are discussed, focused on the shielding section of the planned New Small
Wheel as part of the ATLAS detector upgrade. Those studies supported the discussions
within the upgrade community and decisions made on the final design of
the New Small Wheel. The second part of the thesis covers the design, construction
and functional demonstration of a test facility for gaseous detectors at the
University of Würzburg. Additional studies on the trigger system of the facility are
presented. Especially the precision and reliability of reference timing signals were
investigated.
N2 - In dieser Arbeit werden zwei Projekte vorgestellt, welche beide das gemeinsame
Ziel der Entwicklung von Teilchendetektoren verfolgen. Im ersten Teil der Arbeit
werden ausführliche Simulationsstudien zur Abschirmung behandelt, die sich auf
die Abschirmungsbereiche des geplanten New Small Wheels als Teil der ATLAS-Detektor
Verbesserungen konzentrieren. Diese Studien unterstützten die Diskussionen
innerhalb der Upgrade-Gemeinschaft und Entscheidungen, welche für die
endgültige Kostruktionsplanung des New Small Wheels getroffen wurden. Der
zweite Teil der Arbeit umfasst die Konstruktion, den Aufbau sowie den Funktionsnachweis
eines Teststandes für Gasdetektoren an der Universität Würzburg.
Ebenfalls werden Studien über das Triggersystems des Teststandes dargestellt. Insbesondere
wurden die Präzision und Verlässlichkeit von Referenzzeitsignalen untersucht.
KW - Teilchendetektor
KW - Abschirmung
KW - Simulation
KW - test facility
KW - New Small Wheel
KW - Teststand
KW - Gasionisationsdetektor
KW - European Organization for Nuclear Research. ATLAS Collaboration
KW - Computersimulation
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133084
ER -
TY - JOUR
A1 - Wawra, Stephan
A1 - Fesel, Philipp
A1 - Widmer, Heidi
A1 - Timm, Malte
A1 - Seibel, Jürgen
A1 - Leson, Lisa
A1 - Kesseler, Leona
A1 - Nostadt, Robin
A1 - Hilbert, Magdalena
A1 - Langen, Gregor
A1 - Zuccaro, Alga
T1 - The fungal-specific beta-glucan-binding lectin FGB1 alters cell-wall composition and suppresses glucan-triggered immunity in plants
JF - Nature Communications
N2 - β-glucans are well-known modulators of the immune system in mammals but little is known about β-glucan triggered immunity in planta. Here we show by isothermal titration calorimetry, circular dichroism spectroscopy and nuclear magnetic resonance spectroscopy that the FGB1 gene from the root endophyte Piriformospora indica encodes for a secreted fungal-specific β-glucan-binding lectin with dual function. This lectin has the potential to both alter fungal cell wall composition and properties, and to efficiently suppress β-glucan-triggered immunity in different plant hosts, such as Arabidopsis, barley and Nicotiana benthamiana. Our results hint at the existence of fungal effectors that deregulate innate sensing of β-glucan in plants.
KW - Effectors in plant pathology
KW - Fungal host response
KW - Lectins
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165945
VL - 7
ER -
TY - THES
A1 - Wanzek, Katharina
T1 - The investigation of the function of repair proteins at G-quadruplex structures in \(Saccharomyces\) \(cerevisiae\) revealed that Mms1 promotes genome stability
T1 - Die Untersuchung der Funktion von Reparaturproteinen an G-Quadruplex Strukturen in \(Saccharomyces\) \(cerevisiae\) zeigte, dass Mms1 Genomstabilität fördert
N2 - G-quadruplex structures are highly stable alternative DNA structures that can, when not properly regulated, impede replication fork progression and cause genome instability (Castillo Bosch et al, 2014; Crabbe et al, 2004; Koole et al, 2014; Kruisselbrink et al, 2008; London et al, 2008; Lopes et al, 2011; Paeschke et al, 2013; Paeschke et al, 2011; Piazza et al, 2015; Piazza et al, 2010; Piazza et al, 2012; Ribeyre et al, 2009; Sabouri et al, 2014; Sarkies et al, 2012; Sarkies et al, 2010; Schiavone et al, 2014; Wu & Spies, 2016; Zimmer et al, 2016). The aim of this thesis was to identify novel G-quadruplex interacting proteins in Saccharomyces cerevisiae and to unravel their regulatory function at these structures to maintain genome integrity. Mms1 and Rtt101 were identified as G-quadruplex binding proteins in vitro via a pull-down experiment with subsequent mass spectrometry analysis. Rtt101, Mms1 and Mms22, which are all components of an ubiquitin ligase (Rtt101Mms1/Mms22), are important for the progression of the replication fork following fork stalling (Luke et al, 2006; Vaisica et al, 2011; Zaidi et al, 2008). The in vivo binding of endogenously tagged Mms1 to its target regions was analyzed genome-wide using chromatin-immunoprecipitation followed by deep-sequencing. Interestingly, Mms1 bound independently of Mms22 and Rtt101 to G-rich regions that have the potential to form G-quadruplex structures. In vitro, formation of G-quadruplex structures could be shown for the G-rich regions Mms1 bound to. This binding was observed throughout the cell cycle. Furthermore, the deletion of MMS1 caused replication fork stalling as evidenced by increased association of DNA Polymerase 2 at Mms1 dependent sites. A gross chromosomal rearrangement assay revealed that deletion of MMS1 results in a significantly increased genome instability at G-quadruplex motifs compared to G-rich or non-G-rich regions. Additionally, binding of the helicase Pif1, which unwinds G4 structures in vitro (Paeschke et al, 2013; Ribeyre et al, 2009; Sanders, 2010; Wallgren et al, 2016), to Mms1 binding sites was reduced in mms1 cells. The data presented in this thesis, together with published data, suggests a novel mechanistic model in which Mms1 binds to G-quadruplex structures and enables Pif1 association. This allows for replication fork progression and genome integrity.
N2 - Bei G-quadruplex Strukturen handelt es sich um stabile Sekundärstrukturen der DNA, welche das Fortschreiten der Replikationsgabel behindern und Genominstabilität verursachen können, falls sie nicht konsequent reguliert werden (Castillo Bosch et al, 2014; Crabbe et al, 2004; Koole et al, 2014; Kruisselbrink et al, 2008; London et al, 2008; Lopes et al, 2011; Paeschke et al, 2013; Paeschke et al, 2011; Piazza et al, 2015; Piazza et al, 2010; Piazza et al, 2012; Ribeyre et al, 2009; Sabouri et al, 2014; Sarkies et al, 2012; Sarkies et al, 2010; Schiavone et al, 2014; Wu & Spies, 2016; Zimmer et al, 2016). Ziel dieser Doktorarbeit war es, neue Proteininteraktionspartner dieser Strukturen in Saccharomyces cerevisiae zu identifizieren und zu untersuchen, wie diese Proteine die Strukturen regulieren um Genomstabilität zu gewährleisten. Mit Hilfe eines Pulldown Assays und anschließender massenspektrometrischer Analyse wurden Mms1 und Rtt101 in vitro als Interaktionspartner von G-quadruplex Strukturen identifiziert. Rtt101, Mms1 und Mms22, Komponenten der Ubiquitinligase Rtt101Mms1/Mms22, spielen eine wichtige Rolle beim Fortschreiten der Replikationsgabel, falls dieses durch Agenzien gehemmt wurde (Luke et al, 2006; Vaisica et al, 2011; Zaidi et al, 2008). Durch Chromatin-Immunpräzipitation mit anschließender Hochdurchsatzsequenzierung wurden die Bindestellen von Mms1 identifiziert. Interessanterweise hat Mms1 genomweit an G-reiche Sequenzen gebunden. Diese G-reichen Sequenzen bildeten G-quadruplex Strukturen in vitro aus. Die Bindung von Mms1 erfolgte unabhängig von Rtt101 und Mms22 sowie während des gesamten Zellzyklus. Außerdem kam es zu einer Verlangsamung der Replikationsgabel in mms1 Zellen, was durch eine verstärkte Bindung der DNA Polymerase 2 nachgewiesen wurde. Ein gross chromsomal rearrangement assay zeigte, dass die Genominstabilität in mms1 Zellen signifikant erhöht ist, wenn G-quadruplex Motive, im Vergleich zu nicht-G-reichen oder G-reichen Kontrollregionen, vorhanden sind. Zudem war die Bindung der Helikase Pif1, welche G-quadruplex Strukturen in vitro entwindet (Paeschke et al, 2013; Ribeyre et al, 2009; Sanders, 2010; Wallgren et al, 2016), stark reduziert, wenn Mms1 fehlte. Mit Hilfe der in dieser Doktorarbeit gewonnenen Ergebnisse, sowie mit Hilfe publizierter Daten, lässt sich ein Model postulieren, in welchem Mms1 an G-quadruplexe bindet und somit die Bindung von Pif1 ermöglicht. Dadurch werden das Fortschreiten der Replikationsgabel und die Genomstabilität gewährleistet.
KW - Quadruplex-DNS
KW - DNS-Reparatur
KW - genome stability
KW - Bierhefe
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142547
ER -
TY - JOUR
A1 - Wandrey, Georg
A1 - Wurzel, Joel
A1 - Hoffmann, Kyra
A1 - Ladner, Tobias
A1 - Büchs, Jochen
A1 - Meinel, Lorenz
A1 - Lühmann, Tessa
T1 - Probing unnatural amino acid integration into enhanced green fluorescent protein by genetic code expansion with a high-throughput screening platform
JF - Journal of Biological Engineering
N2 - Background
Genetic code expansion has developed into an elegant tool to incorporate unnatural amino acids (uAA) at predefined sites in the protein backbone in response to an amber codon. However, recombinant production and yield of uAA comprising proteins are challenged due to the additional translation machinery required for uAA incorporation.
Results
We developed a microtiter plate-based high-throughput monitoring system (HTMS) to study and optimize uAA integration in the model protein enhanced green fluorescence protein (eGFP). Two uAA, propargyl-L-lysine (Plk) and (S)-2-amino-6-((2-azidoethoxy) carbonylamino) hexanoic acid (Alk), were incorporated at the same site into eGFP co-expressing the native PylRS/tRNAPyl CUA pair originating from Methanosarcina barkeri in E. coli. The site-specific uAA functionalization was confirmed by LC-MS/MS analysis. uAA-eGFP production and biomass growth in parallelized E. coli cultivations was correlated to (i) uAA concentration and the (ii) time of uAA addition to the expression medium as well as to induction parameters including the (iii) time and (iv) amount of IPTG supplementation. The online measurements of the HTMS were consolidated by end point-detection using standard enzyme-linked immunosorbent procedures.
Conclusion
The developed HTMS is powerful tool for parallelized and rapid screening. In light of uAA integration, future applications may include parallelized screening of different PylRS/tRNAPyl CUA pairs as well as further optimization of culture conditions.
KW - protein engineering
KW - amber codon suppression
KW - online monitoring system
KW - high-throughput screening
KW - unnatural amino acid
KW - bio-orthogonal chemistry
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166304
VL - 10
IS - 11
ER -
TY - JOUR
A1 - Walz, Nora
A1 - Mühlberger, Andreas
A1 - Pauli, Paul
T1 - A human open field test reveals thigmotaxis related to agoraphobic fear
JF - Biological Psychiatry
N2 - BACKGROUND:
Thigmotaxis refers to a specific behavior of animals (i.e., to stay close to walls when exploring an open space). Such behavior can be assessed with the open field test (OFT), which is a well-established indicator of animal fear. The detection of similar open field behavior in humans may verify the translational validity of this paradigm. Enhanced thigmotaxis related to anxiety may suggest the relevance of such behavior for anxiety disorders, especially agoraphobia.
METHODS:
A global positioning system was used to analyze the behavior of 16 patients with agoraphobia and 18 healthy individuals with a risk for agoraphobia (i.e., high anxiety sensitivity) during a human OFT and compare it with appropriate control groups (n = 16 and n = 19). We also tracked 17 patients with agoraphobia and 17 control participants during a city walk that involved walking through an open market square. RESULTS: Our human OFT triggered thigmotaxis in participants; patients with agoraphobia and participants with high anxiety sensitivity exhibited enhanced thigmotaxis. This behavior was evident in increased movement lengths along the wall of the natural open field and fewer entries into the center of the field despite normal movement speed and length. Furthermore, participants avoided passing through the market square during the city walk, indicating again that thigmotaxis is related to agoraphobia.
CONCLUSIONS:
This study is the first to our knowledge to verify the translational validity of the OFT and to reveal that thigmotaxis, an evolutionarily adaptive behavior shown by most species, is related to agoraphobia, a pathologic fear of open spaces, and anxiety sensitivity, a risk factor for agoraphobia.
KW - Agoraphobia
KW - Animal models
KW - Anxiety sensitivity
KW - Avoidance behavior
KW - Openfield test
KW - Thigmotaxis
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187607
VL - 80
IS - 5
ER -
TY - JOUR
A1 - Walter, T.
A1 - Collenburg, L.
A1 - Japtok, L.
A1 - Kleuser, B.
A1 - Schneider-Schaulies, S.
A1 - Müller, N.
A1 - Becam, J.
A1 - Schubert-Unkmeir, A.
A1 - Kong, J. N.
A1 - Bieberich, E.
A1 - Seibel, J.
T1 - Incorporation and visualization of azido-functionalized N-oleoyl serinol in Jurkat cells, mouse brain astrocytes, 3T3 fibroblasts and human brain microvascular endothelial cells
JF - Chemical Communications
N2 - The synthesis and biological evaluation of azido-N-oleoyl serinol is reported. It mimicks biofunctional lipid ceramides and has shown to be capable of click reactions for cell membrane imaging in Jurkat and human brain microvascular endothelial cells.
KW - Ceramide
KW - Apoptosis
KW - Golgi
KW - N-oleoyl serinol
KW - Jurkat cells
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-191263
VL - 52
IS - 55
ER -
TY - JOUR
A1 - Walper, Elisabeth
A1 - Weiste, Christoph
A1 - Mueller, Martin J.
A1 - Hamberg, Mats
A1 - Dröge-Laser, Wolfgang
T1 - Screen Identifying Arabidopsis Transcription Factors Involved in the Response to 9-Lipoxygenase-Derived Oxylipins
JF - PLoS One
N2 - 13-Lipoxygenase-derived oxylipins, such as jasmonates act as potent signaling molecules in plants. Although experimental evidence supports the impact of oxylipins generated by the 9-Lipoxygenase (9-LOX) pathway in root development and pathogen defense, their signaling function in plants remains largely elusive. Based on the root growth inhibiting properties of the 9-LOX-oxylipin 9-HOT (9-hydroxy-10,12,15-octadecatrienoic acid), we established a screening approach aiming at identifying transcription factors (TFs) involved in signaling and/or metabolism of this oxylipin. Making use of the AtTORF-Ex (Arabidopsis thaliana Transcription Factor Open Reading Frame Expression) collection of plant lines overexpressing TF genes, we screened for those TFs which restore root growth on 9-HOT. Out of 6,000 lines, eight TFs were recovered at least three times and were therefore selected for detailed analysis. Overexpression of the basic leucine Zipper (bZIP) TF TGA5 and its target, the monoxygenase CYP81D11 reduced the effect of added 9-HOT, presumably due to activation of a detoxification pathway. The highly related ETHYLENE RESPONSE FACTORs ERF106 and ERF107 induce a broad detoxification response towards 9-LOX-oxylipins and xenobiotic compounds. From a set of 18 related group S-bZIP factors isolated in the screen, bZIP11 is known to participate in auxin-mediated root growth and may connect oxylipins to root meristem function. The TF candidates isolated in this screen provide starting points for further attempts to dissect putative signaling pathways involving 9-LOX-derived oxylipins.
KW - Jasmonic acid
KW - root growth
KW - arabidopsis thaliana
KW - detoxification
KW - seedlings
KW - stress signaling cascade
KW - hyperexpression techniques
KW - ranscription factors
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146857
VL - 11
IS - 4
ER -
TY - THES
A1 - Wahl, Oliver
T1 - Impurity Profiling of Challenging Active Pharmaceutical Ingredients without Chromophore
T1 - Erstellen von Verunreinigungsprofilen von anspruchsvollen Wirkstoffen ohne Chromophor
N2 - The impurity profiling of pharmaceutical ingredients can oppose many challenges. The best part of active pharmaceutical ingredients (APIs) and the related substances are detectable by UV detection, a very common detection principle. However, if an API lacks a suitable chromophore other means of detection are necessary. The corona charged aerosol detector (CAD) is a detector capable of detecting substances independent of their chemical structure. This “universal” detector has only one limitation: The analyte has to have a sufficiently low vapor pressure. Another important challenge that comes often together with the lack of a chromophore concerns the separation. These substances (e.g. most amino acids and derivatives) often contain structures that make them difficult to retain on conventional reversed phase columns.
Possible solutions to overcome these challenges, like the application of the CAD and the benefit of so-called mixed-mode stationary phases in impurity profiling for pharmacopoeial purposes were explored in this work. The related substances analyzed in this thesis comprise amino acids, inorganic ions, bisphosphonic acids, basic and acidic derivatives of amino acids (esters and amides).
The successful development and validation of mixed-mode liquid chromatography methods with CAD detection for carbocisteine and ibandronate sodium might help to increase the acceptance of this versatile detector in the pharmaceutical industry and in official authorities dealing with the determination of related substances.
The combination of UV and CAD detection proved very useful during the analysis of Bicisate. Most of the related substances and some unidentified impurities were detectable by CAD whereas a synthesis by-product, a semi-volatile ester, was only detectable in the UV trace. The simple combination covers all relevant impurities in a single analysis.
Two truly orthogonal methods regarding separation and detection for the enantiomeric purity of magnesium-L-aspartate helped to find the reason for elevated D aspartic acid content in the drug substance. A very quick and sensitive indirect separation using the OPA derivatization with NAC was developed as a powerful screening tool, whereas the direct separation of D- and L-CBQCA-Asp derivatives confirmed the results. Both methods were optimized in order to do without substances mentioned on the REACH list, like sodium tetraborate which is very frequently applied in standard derivatization protocols and CE separations.
The importance of orthogonal detection principles in the determination of related substances of amino acids was discussed in a review article dealing with the revision of amino acid monographs in the Ph. Eur..
N2 - Die Reinheitsprüfung pharmazeutischer Wirkstoffe kann den Analytiker vor verschiedene Hürden stellen. So gilt für den größten Teil pharmazeutischer Wirkstoffe und deren verwandte Substanzen, dass sie mit Hilfe des weit verbreiteten UV-Detektors nachweisbar sind. Verfügt ein Wirkstoff hingegen nicht über ein geeignetes Chromophor, so benötigt man andere Möglichkeiten der Detektion. Der corona charged aerosol detector (CAD) ist in der Lage Substanzen unabhängig von ihrer chemischen Struktur zu detektieren, vorausgesetzt, sie sind schwerflüchtig. Eine weitere Herausforderung, die häufig mit dem Fehlen eines Chromophors einhergeht betrifft die Trennung. Verbindungen dieser Art (z.B. die meisten Aminosäuren und deren Derivate) enthalten häufig Strukturen, die eine Trennung auf konventionellen Umkehrphasen erschweren.
Mögliche Ansätze um die genannten Herausforderungen zu meistern, wie zum Beispiel die Verwendung des CAD und sogenannter mixed-mode Phasen in der pharmazeutischen Reinheitsanalytik wurden erarbeitet und an konkreten Anwendungen erprobt. Die in dieser Arbeit bestimmten verwandten Substanzen sind vor allem Aminosäuren, anorganische Ionen, Bisphosphonate sowie basische und saure Derivate von Aminosäuren (Ester und Amide).
Die erfolgreiche Entwicklung und Validierung von mixed-mode flüssig-chromatographischer Methoden kombiniert mit CAD für Carbocistein und Ibandronat Natrium könnte dabei helfen die Akzeptanz in der Pharmazeutischen Industrie und bei den für Reinheitsprüfungen zuständigen Behörden für diesen vielseitigen Detektor zu verbessern.
Die Kombination von UV-Detektion und CAD erwies sich bei der Analyse von Bicisate als sehr nützlich. Die meisten verwandten Substanzen und einige unbekannte Verunreinigungen konnten mittels CAD detektiert werden, während ein Nebenprodukt der Synthese, ein halb-flüchtiger Ester, nur mit Hilfe des UV Detektors sichtbar war. Die Kombination zweier Detektionstechniken ermöglichte die Bestimmung aller relevanten Verunreinigungen in einer einzigen Analyse.
Die Bestimmung der optischen Reinheit von Magnesium-L-Aspartat gelang mittels zweier orthogonaler Methoden und der Grund für das Auftreten von erhöhten Konzentrationen an D-Aspartat wurde gefunden. Eine schnelle indirekte Bestimmung der OPA/NAC-Derivate eignete sich als Screening-tool, während die direkte Trennung der enantiomeren CBQCA-Derivate die Ergebnisse bestätigte. Beide Methoden wurden im Hinblick darauf optimiert, dass sie ohne Substanzen wie Natriumtetraborat, eine Substanz auf der REACH Liste für besonders besorgniserregende Substanzen, sowie gebräuchlicher Puffer bei Derivatisierungsreaktionen und CZE Trennungen, auskamen.
Die Bedeutung von orthogonalen Detektionstechniken bei der Bestimmung der verwandten Substanzen von Aminosäuren wurde in einem Übersichtsartikel, der in Zusammenhang mit der Revision von Aminosäuren Monographien des Europäischen Arzneibuches steht, diskutiert.
KW - Chromatographie
KW - Verunreinigung
KW - Impurity Profiling
KW - Amino acids
KW - Corona charged aerosol detector
KW - Aminosäuren
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137205
ER -
TY - THES
A1 - Väth, Stefan Kilian
T1 - On the Role of Spin States in Organic Semiconductor Devices
T1 - Die Rolle von Spin Zuständen in organischen Halbleiterbauteilen
N2 - The present work addressed the influence of spins on fundamental processes in organic
semiconductors. In most cases, the role of spins in the conversion of sun light
into electricity was of particular interest. However, also the reversed process, an electric
current creating luminescence, was investigated by means of spin sensitive measurements.
In this work, many material systems were probed with a variety of innovative
detection techniques based on electron paramagnetic resonance spectroscopy.
More precisely, the observable could be customized which resulted in the experimental
techniques photoluminescence detected magnetic resonance (PLDMR), electrically
detected magnetic resonance (EDMR), and electroluminescence detected magnetic
resonance (ELDMR). Besides the commonly used continuous wave EPR spectroscopy,
this selection of measurement methods yielded an access to almost all intermediate
steps occurring in organic semiconductors during the conversion of light into electricity
and vice versa. Special attention was paid to the fact that all results were applicable
to realistic working conditions of the investigated devices, i.e. room temperature application and realistic illumination conditions.
N2 - Die vorliegende Arbeit behandelt den Einfluss der Elektronenspins auf grundlegende Prozesse in organischen Halbleitern. In den meisten Fällen wurde der Spineinfluss während der Umwandlung von Sonnenlicht in Elektrizität untersucht. Zusätzlich wurde in einer Studie der gegenteilige Prozess behandelt. Dabei wurde der Einfluss der Spins auf die Umwandlung von elektrischem Strom in Licht betrachtet. Es wurden viele verschiedene Materialsysteme verwendet, die mit einer Vielzahl an Methoden vermessen wurden, welche alle auf dem Prinzip der Elektronenspinresonanz beruhen. Dabei wurde stets die Messgröße variiert, was zu den verwendeten Messmethoden Photolumineszenz detektierte Magnetresonanz (PLDMR), elektrisch detektierte Magnetresonanz (EDMR) und Elektrolumineszenz detektierte Magnetresonanz (ELDMR) geführt hat. Zusam- men mit der gewöhnlichen Elektronenspinresonanz Spektroskopie führt diese Auswahl
an vielfältigen Messmethoden dazu, dass so gut wie alle Zwischenschritte bei der Umwand- lung von Licht in Elektrizität als auch von Elektrizität in Licht untersucht werden können. Besonderes Augenmerk wurde darauf gelegt, dass alle Messungen auf realistische Bedingungen übertragbar sind, d.h. bei Raumtemperatur und unter normalen Beleuchtungsstärken und -wellenlängen.
Zu Beginn der Arbeit wurde ein kurzer Überblick über die historische Entwicklung von organischen Solarzellen gegeben, zusammen mit der Erläuterung von grundlegenden Prozessen in den untersuchten Bauteilen, stets auch hinsichtlich der vorkommenden Spinzustände. Desweiteren wurde die Solarzellencharakterisierung und die Morphologie der aktiven Schicht diskutiert. Das darauf folgende Kapitel behandelte die theoretische Beschreibung des Magnetfeldeffekts auf Spinzustände und diverse Wechselwirkungsmechanismen. Darüber hinaus wurde diskutiert, wie Mikrowellen die vom Magnetfeld ausgerichteten Spins beeinflussen können. Zu guter Letzt wurden verschiedene Modelle vorgestellt, mit deren Hilfe sich die erzielten Ergebnisse interpretieren lassen. Das nächste Kapitel beschreibt schließlich detailliert die experimentellen Feinheiten, wie verwendete Materialien, Probenherstellung und verschiedene Spektrometer Konfigurationen.
Das erste Ergebnis Kapitel beschreibt den Einfluss des Zusatzmittels 1,8-Dijodoktan auf das Materialsystem PTB7:PC70BM. Dies wurde mit Hilfe von konventioneller Elek- tronenspinresonanz untersucht, welche es ermöglicht zwischen Elektronen auf dem Akzeptor- und Polaronen auf dem Donormaterial zu unterscheiden. Ergänzend dazu wurden Röntgenphotoelektronenspektroskopiemessungen durchgeführt, welche zu dem Ergebnis führten, dass Jod trotz Hochvakuumtrocknung mit der relativen hohen Konzentration von (7.3±2.1)·1019 1 in dem Material verbleibt. Zudem bleibt Jod wahrscheinlich bevorzugt in der Akzeptorphase. Es wurde außerdem kein elektronischer Doping- effekt gefunden. Nichtsdestotrotz wird dieses Ergebnis einen Einfluss auf die zukünftige Wahl des Zusatzmittels haben.
Kapitel 6 handelt von der Entstehung von Triplett Exzitonen in dem Materialsystem p-DTS(FBTTh2)2:PC70BM, wobei das Donormaterial aus löslichen kleinen Molekülen besteht, anstatt aus Polymeren. Mit Hilfe von PLDMR Messungen konnten die Entstehungsmechanismen Elektronenrücktransfer, sowie inter system crossing den verschiedenen Proben zugeordnet werden. Der genaue Mechanismus hängt jedoch stark von der Morphologie des untersuchten Materialsystems ab. Durch den Nachweis von Triplett Exzitonen bei Raumtemperatur konnte die Relevanz der Ergebnisse auch bei realen Bedingungen bestätigt werden. Vergleicht man das Triplett Vorkommen mit den So- larzelleneffizienzen konnte keine Korrelation erkannt werden. Daraus ergibt sich, dass Triplett Exzitonen für das untersuchte Materialsystem keine Effizienz limitierende Größe darstellen. Zum Abschluss wurde die Ausrichtung der Moleküle auf dem Substrat mit Hilfe von winkelabhängigen Messungen bestätigt.
Der Einfluss des Zusatzmittels Galvinoxyl auf die Funktionsweise von organischen Solarzellen wird in Kapitel 7 untersucht. Es wurden PLDMR durchgeführt, die gezeigt haben, dass Galvinoxyl in der Lage ist Spin Zustände zu verändern, wie von der Literatur vorhergesagt. Aufgrund dessen handelt es sich um einen konkurrierenden Prozess gegenüber den erzeugten Spin resonanten Bedingungen. Durch die Messung an verschiedenen Doping Konzentrationen konnte ein Optimum von 3.2 % für das Materialsystem P3HT:PC60BM bestimmt werden. Trotzallem ist es unwahrscheinlich, dass der
sehr große Anstieg des Photostroms in mit Galvinoxyl gedopten Solarzellen auf spinabhängige Prozesse zurückzuführen ist.
Die Quantifizierung von spinabhängigen Prozessen in organischen Solarzellen bein- haltet viele Schwierigkeiten. Durch die Kombination des EDMR Messprinzips mit der Ladungsträgerextraktionsmethode OTRACE war es jedoch möglich, einen spinabhängigen Rekombinationsanteil von (0.012±0.009)% bei Raumtemperatur und (0.052±0.031)% bei 200 K für das Materialsystem P3HT:PC70BM zu bestimmen. Darüber hinaus wurde eine Interpretation eingeführt, die in der Lage ist, das Zustandekommen des EDMR Signals zu erklären.
Im letzten Ergebnisteil (Kapitel 9) wurde der Fokus darauf gelegt, wie Spins die Funktionsweise von organischen Leuchtdioden (OLEDs) beeinflussen, die auf thermisch aktivierter verzögerter Lumineszenz (TADF) basieren. Dabei wurden verschiedene Detektionsverfahren verwendet, wobei sich heraus gestellt hat, dass ELDMR das einzig verwendbare darstellt. Damit konnten durch temperaturabhängige Messungen der energetische Unterschied zwischen dem Singulett- und Triplett Exciplex Zustand ∆EST bestimmt werden. Es ergaben sich (20.5±1.2) meV für THCA:BPhen und (68.3±5.4) meV für m-MTDATA:BPhen. Durch diese Messungen wurde zum ersten Mal zweifelsfrei der Einfluss von Spins in der Entstehung der Elektrolumineszenz von TADF OLEDs gezeigt. Aufgrund der Diskussion von möglichen Gründen, die für die verschiedenen Werte von ∆EST verantwortlich sind, konnten neue Vorgaben für zukünftige Materialkombinationen und -synthese gefunden werden.
Zusammenfassend lässt sich sagen, dass die vorliegende Arbeit einen bedeutenden Beitrag geliefert hat, um spinabhängige Prozesse in organischen Halbleitern aufzuklären. Darauf aufbauend werden Folgestudien vielleicht eines Tages sämtliche spinabhängigen Prozesse in diesen viel versprechenden Materialsystemen erklären können.
KW - Organischer Halbleiter
KW - Elektronenspin
KW - Polymerhalbleiter
KW - Organic Semiconductors
KW - Electron Spin Resonance
KW - Elektronenspinresonanz
KW - Spin
KW - Spin-eins-System
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-141894
ER -
TY - JOUR
A1 - Vučićević, Dubravka
A1 - Gehre, Maja
A1 - Dhamija, Sonam
A1 - Friis-Hansen, Lennart
A1 - Meierhofer, David
A1 - Sauer, Sascha
A1 - Ørom, Ulf Andersson
T1 - The long non-coding RNA PARROT is an upstream regulator of c-Myc and affects proliferation and translation
JF - Oncotarget
N2 - Long non-coding RNAs are important regulators of gene expression and signaling pathways. The expression of long ncRNAs is dysregulated in cancer and other diseases. The identification and characterization of long ncRNAs is often challenging due to their low expression level and localization to chromatin. Here, we identify a functional long ncRNA, PARROT (Proliferation Associated RNA and Regulator Of Translation) transcribed by RNA polymerase II and expressed at a relatively high level in a number of cell lines. The PARROT long ncRNA is associated with proliferation in both transformed and normal cell lines. We characterize the long ncRNA PARROT as an upstream regulator of c-Myc affecting cellular proliferation and translation using RNA sequencing and mass spectrometry following depletion of the long ncRNA. PARROT is repressed during senescence of human mammary epithelial cells and overexpressed in some cancers, suggesting an important association with proliferation through regulation of c-Myc. With this study, we add to the knowledge of cytoplasmic functional long ncRNAs and extent the long ncRNA-Myc regulatory network in transformed and normal cells.
KW - PARROT
KW - c-Myc
KW - long ncRNA
KW - upstream regulator
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166519
VL - 7
IS - 23
ER -
TY - JOUR
A1 - Volckmar, Anna-Lena
A1 - Han, Chung Ting
A1 - Pütter, Carolin
A1 - Haas, Stefan
A1 - Vogel, Carla I. G.
A1 - Knoll, Nadja
A1 - Struve, Christoph
A1 - Göbel, Maria
A1 - Haas, Katharina
A1 - Herrfurth, Nikolas
A1 - Jarick, Ivonne
A1 - Grallert, Harald
A1 - Schürmann, Annette
A1 - Al-Hasani, Hadi
A1 - Hebebrand, Johannes
A1 - Sauer, Sascha
A1 - Hinney, Anke
T1 - Analysis of Genes Involved in Body Weight Regulation by Targeted Re-Sequencing
JF - PLoS ONE
N2 - Introduction
Genes involved in body weight regulation that were previously investigated in genome-wide association studies (GWAS) and in animal models were target-enriched followed by massive parallel next generation sequencing.
Methods
We enriched and re-sequenced continuous genomic regions comprising FTO, MC4R, TMEM18, SDCCAG8, TKNS, MSRA and TBC1D1 in a screening sample of 196 extremely obese children and adolescents with age and sex specific body mass index (BMI) ≥ 99th percentile and 176 lean adults (BMI ≤ 15th percentile). 22 variants were confirmed by Sanger sequencing. Genotyping was performed in up to 705 independent obesity trios (extremely obese child and both parents), 243 extremely obese cases and 261 lean adults.
Results and Conclusion
We detected 20 different non-synonymous variants, one frame shift and one nonsense mutation in the 7 continuous genomic regions in study groups of different weight extremes. For SNP Arg695Cys (rs58983546) in TBC1D1 we detected nominal association with obesity (pTDT = 0.03 in 705 trios). Eleven of the variants were rare, thus were only detected heterozygously in up to ten individual(s) of the complete screening sample of 372 individuals. Two of them (in FTO and MSRA) were found in lean individuals, nine in extremely obese. In silico analyses of the 11 variants did not reveal functional implications for the mutations. Concordant with our hypothesis we detected a rare variant that potentially leads to loss of FTO function in a lean individual. For TBC1D1, in contrary to our hypothesis, the loss of function variant (Arg443Stop) was found in an obese individual. Functional in vitro studies are warranted.
KW - body weight regulation
KW - genes
KW - targeted re-sequencing
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167274
VL - 11
IS - 2
ER -
TY - JOUR
A1 - Vogtmann, Emily
A1 - Hua, Xing
A1 - Zeller, Georg
A1 - Sunagawa, Shinichi
A1 - Voigt, Anita Y.
A1 - Hercog, Rajna
A1 - Goedert, James J.
A1 - Shi, Jianxin
A1 - Bork, Peer
A1 - Sinha, Rashmi
T1 - Colorectal Cancer and the Human Gut Microbiome: Reproducibility with Whole-Genome Shotgun Sequencing
JF - PLoS ONE
N2 - Accumulating evidence indicates that the gut microbiota affects colorectal cancer development, but previous studies have varied in population, technical methods, and associations with cancer. Understanding these variations is needed for comparisons and for potential pooling across studies. Therefore, we performed whole-genome shotgun sequencing on fecal samples from 52 pre-treatment colorectal cancer cases and 52 matched controls from Washington, DC. We compared findings from a previously published 16S rRNA study to the metagenomics-derived taxonomy within the same population. In addition, metagenome-predicted genes, modules, and pathways in the Washington, DC cases and controls were compared to cases and controls recruited in France whose specimens were processed using the same platform. Associations between the presence of fecal Fusobacteria, Fusobacterium, and Porphyromonas with colorectal cancer detected by 16S rRNA were reproduced by metagenomics, whereas higher relative abundance of Clostridia in cancer cases based on 16S rRNA was merely borderline based on metagenomics. This demonstrated that within the same sample set, most, but not all taxonomic associations were seen with both methods. Considering significant cancer associations with the relative abundance of genes, modules, and pathways in a recently published French metagenomics dataset, statistically significant associations in the Washington, DC population were detected for four out of 10 genes, three out of nine modules, and seven out of 17 pathways. In total, colorectal cancer status in the Washington, DC study was associated with 39% of the metagenome-predicted genes, modules, and pathways identified in the French study. More within and between population comparisons are needed to identify sources of variation and disease associations that can be reproduced despite these variations. Future studies should have larger sample sizes or pool data across studies to have sufficient power to detect associations that are reproducible and significant after correction for multiple testing.
KW - colorectal cancer
KW - gut microbiota
KW - whole-genome shotgun sequencing
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166904
VL - 11
IS - 5
ER -
TY - JOUR
A1 - Vigorito, Elena
A1 - Kuchenbaecker, Karoline B.
A1 - Beesley, Jonathan
A1 - Adlard, Julian
A1 - Agnarsson, Bjarni A.
A1 - Andrulis, Irene L.
A1 - Arun, Banu K.
A1 - Barjhoux, Laure
A1 - Belotti, Muriel
A1 - Benitez, Javier
A1 - Berger, Andreas
A1 - Bojesen, Anders
A1 - Bonanni, Bernardo
A1 - Brewer, Carole
A1 - Caldes, Trinidad
A1 - Caligo, Maria A.
A1 - Campbell, Ian
A1 - Chan, Salina B.
A1 - Claes, Kathleen B. M.
A1 - Cohn, David E.
A1 - Cook, Jackie
A1 - Daly, Mary B.
A1 - Damiola, Francesca
A1 - Davidson, Rosemarie
A1 - de Pauw, Antoine
A1 - Delnatte, Capucine
A1 - Diez, Orland
A1 - Domchek, Susan M.
A1 - Dumont, Martine
A1 - Durda, Katarzyna
A1 - Dworniczak, Bernd
A1 - Easton, Douglas F.
A1 - Eccles, Diana
A1 - Ardnor, Christina Edwinsdotter
A1 - Eeles, Ros
A1 - Ejlertsen, Bent
A1 - Ellis, Steve
A1 - Evans, D. Gareth
A1 - Feliubadalo, Lidia
A1 - Fostira, Florentia
A1 - Foulkes, William D.
A1 - Friedman, Eitan
A1 - Frost, Debra
A1 - Gaddam, Pragna
A1 - Ganz, Patricia A.
A1 - Garber, Judy
A1 - Garcia-Barberan, Vanesa
A1 - Gauthier-Villars, Marion
A1 - Gehrig, Andrea
A1 - Gerdes, Anne-Marie
A1 - Giraud, Sophie
A1 - Godwin, Andrew K.
A1 - Goldgar, David E.
A1 - Hake, Christopher R.
A1 - Hansen, Thomas V. O.
A1 - Healey, Sue
A1 - Hodgson, Shirley
A1 - Hogervorst, Frans B. L.
A1 - Houdayer, Claude
A1 - Hulick, Peter J.
A1 - Imyanitov, Evgeny N.
A1 - Isaacs, Claudine
A1 - Izatt, Louise
A1 - Izquierdo, Angel
A1 - Jacobs, Lauren
A1 - Jakubowska, Anna
A1 - Janavicius, Ramunas
A1 - Jaworska-Bieniek, Katarzyna
A1 - Jensen, Uffe Birk
A1 - John, Esther M.
A1 - Vijai, Joseph
A1 - Karlan, Beth Y.
A1 - Kast, Karin
A1 - Khan, Sofia
A1 - Kwong, Ava
A1 - Laitman, Yael
A1 - Lester, Jenny
A1 - Lesueur, Fabienne
A1 - Liljegren, Annelie
A1 - Lubinski, Jan
A1 - Mai, Phuong L.
A1 - Manoukian, Siranoush
A1 - Mazoyer, Sylvie
A1 - Meindl, Alfons
A1 - Mensenkamp, Arjen R.
A1 - Montagna, Marco
A1 - Nathanson, Katherine L.
A1 - Neuhausen, Susan L.
A1 - Nevanlinna, Heli
A1 - Niederacher, Dieter
A1 - Olah, Edith
A1 - Olopade, Olufunmilayo I.
A1 - Ong, Kai-ren
A1 - Osorio, Ana
A1 - Park, Sue Kyung
A1 - Paulsson-Karlsson, Ylva
A1 - Pedersen, Inge Sokilde
A1 - Peissel, Bernard
A1 - Peterlongo, Paolo
A1 - Pfeiler, Georg
A1 - Phelan, Catherine M.
A1 - Piedmonte, Marion
A1 - Poppe, Bruce
A1 - Pujana, Miquel Angel
A1 - Radice, Paolo
A1 - Rennert, Gad
A1 - Rodriguez, Gustavo C.
A1 - Rookus, Matti A.
A1 - Ross, Eric A.
A1 - Schmutzler, Rita Katharina
A1 - Simard, Jacques
A1 - Singer, Christian F.
A1 - Slavin, Thomas P.
A1 - Soucy, Penny
A1 - Southey, Melissa
A1 - Steinemann, Doris
A1 - Stoppa-Lyonnet, Dominique
A1 - Sukiennicki, Grzegorz
A1 - Sutter, Christian
A1 - Szabo, Csilla I.
A1 - Tea, Muy-Kheng
A1 - Teixeira, Manuel R.
A1 - Teo, Soo-Hwang
A1 - Terry, Mary Beth
A1 - Thomassen, Mads
A1 - Tibiletti, Maria Grazia
A1 - Tihomirova, Laima
A1 - Tognazzo, Silvia
A1 - van Rensburg, Elizabeth J.
A1 - Varesco, Liliana
A1 - Varon-Mateeva, Raymonda
A1 - Vratimos, Athanassios
A1 - Weitzel, Jeffrey N.
A1 - McGuffog, Lesley
A1 - Kirk, Judy
A1 - Toland, Amanda Ewart
A1 - Hamann, Ute
A1 - Lindor, Noralane
A1 - Ramus, Susan J.
A1 - Greene, Mark H.
A1 - Couch, Fergus J.
A1 - Offit, Kenneth
A1 - Pharoah, Paul D. P.
A1 - Chenevix-Trench, Georgia
A1 - Antoniou, Antonis C.
T1 - Fine-Scale Mapping at 9p22.2 Identifies Candidate Causal Variants That Modify Ovarian Cancer Risk in BRCA1 and BRCA2 Mutation Carriers
JF - PLoS ONE
N2 - Population-based genome wide association studies have identified a locus at 9p22.2 associated with ovarian cancer risk, which also modifies ovarian cancer risk in BRCA1 and BRCA2 mutation carriers. We conducted fine-scale mapping at 9p22.2 to identify potential causal variants in BRCA1 and BRCA2 mutation carriers. Genotype data were available for 15,252 (2,462 ovarian cancer cases) BRCA1 and 8,211 (631 ovarian cancer cases) BRCA2 mutation carriers. Following genotype imputation, ovarian cancer associations were assessed for 4,873 and 5,020 SNPs in BRCA1 and BRCA 2 mutation carriers respectively, within a retrospective cohort analytical framework. In BRCA1 mutation carriers one set of eight correlated candidate causal variants for ovarian cancer risk modification was identified (top SNP rs10124837, HR: 0.73, 95%CI: 0.68 to 0.79, p-value 2× 10−16). These variants were located up to 20 kb upstream of BNC2. In BRCA2 mutation carriers one region, up to 45 kb upstream of BNC2, and containing 100 correlated SNPs was identified as candidate causal (top SNP rs62543585, HR: 0.69, 95%CI: 0.59 to 0.80, p-value 1.0 × 10−6). The candidate causal in BRCA1 mutation carriers did not include the strongest associated variant at this locus in the general population. In sum, we identified a set of candidate causal variants in a region that encompasses the BNC2 transcription start site. The ovarian cancer association at 9p22.2 may be mediated by different variants in BRCA1 mutation carriers and in the general population. Thus, potentially different mechanisms may underlie ovarian cancer risk for mutation carriers and the general population.
KW - fine-scale mapping
KW - ovarian cancer
KW - genetics
KW - BRCA1
KW - BRCA2
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166869
VL - 11
IS - 7
ER -
TY - JOUR
A1 - Viera, Jonathan Trujillo
A1 - El-Merahbi, Rabih
A1 - Nieswandt, Bernhard
A1 - Stegner, David
A1 - Sumara, Grzegorz
T1 - Phospholipases D1 and D2 Suppress Appetite and Protect against Overweight
JF - PLoS ONE
N2 - Obesity is a major risk factor predisposing to the development of peripheral insulin resistance and type 2 diabetes (T2D). Elevated food intake and/or decreased energy expenditure promotes body weight gain and acquisition of adipose tissue. Number of studies implicated phospholipase D (PLD) enzymes and their product, phosphatidic acid (PA), in regulation of signaling cascades controlling energy intake, energy dissipation and metabolic homeostasis. However, the impact of PLD enzymes on regulation of metabolism has not been directly determined so far. In this study we utilized mice deficient for two major PLD isoforms, PLD1 and PLD2, to assess the impact of these enzymes on regulation of metabolic homeostasis. We showed that mice lacking PLD1 or PLD2 consume more food than corresponding control animals. Moreover, mice deficient for PLD2, but not PLD1, present reduced energy expenditure. In addition, deletion of either of the PLD enzymes resulted in development of elevated body weight and increased adipose tissue content in aged animals. Consistent with the fact that elevated content of adipose tissue predisposes to the development of hyperlipidemia and insulin resistance, characteristic for the pre-diabetic state, we observed that Pld1\(^{-/-}\) and Pld2\(^{-/-}\) mice present elevated free fatty acids (FFA) levels and are insulin as well as glucose intolerant. In conclusion, our data suggest that deficiency of PLD1 or PLD2 activity promotes development of overweight and diabetes.
KW - enzyme regulation
KW - insulin resistance
KW - body weight
KW - mouse models
KW - bioenergetics
KW - insulin
KW - hypothalamus
KW - adipose tissue
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-179729
VL - 11
IS - 6
ER -
TY - JOUR
A1 - Verma, Pramod Kumar
A1 - Steinbacher, Andreas
A1 - Schmiedel, Alexander
A1 - Nuernberger, Patrick
A1 - Brixner, Tobias
T1 - Excited-state intramolecular proton transfer of 2-acetylindan-1,3-dione studied by ultrafast absorption and fluorescence spectroscopy
JF - Structural Dynamics
N2 - We employ transient absorption from the deep-UV to the visible region and fluorescence upconversion to investigate the photoinduced excited-state intramolecular proton-transfer dynamics in a biologically relevant drug molecule, 2-acetylindan-1,3-dione. The molecule is a ß-diketone which in the electronic ground state exists as exocyclic enol with an intramolecular H-bond. Upon electronic excitation at 300 nm, the first excited state of the exocyclic enol is initially populated, followed by ultrafast proton transfer (≈160 fs) to form the vibrationally hot endocyclic enol. Subsequently, solvent-induced vibrational relaxation takes place (≈10 ps) followed by decay (≈390 ps) to the corresponding ground state.
KW - time resolved spectroscopy
KW - ground states
KW - fluorescence spectra
KW - absorption spectra
KW - ultraviolet light
KW - hydrogen bonding
KW - excited states
KW - reaction mechanisms
KW - fluorescence
KW - solvents
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-181301
VL - 3
ER -
TY - JOUR
A1 - Verma, Nidhi
A1 - Rai, Amit Kumar
A1 - Kaushik, Vibha
A1 - Brünnert, Daniela
A1 - Chahar, Kirti Raj
A1 - Pandey, Janmejay
A1 - Goyal, Pankaj
T1 - Identification of gefitinib off-targets using a structure-based systems biology approach; their validation with reverse docking and retrospective data mining
JF - Scientific Reports
N2 - Gefitinib, an EGFR tyrosine kinase inhibitor, is used as FDA approved drug in breast cancer and non-small cell lung cancer treatment. However, this drug has certain side effects and complications for which the underlying molecular mechanisms are not well understood. By systems biology based in silico analysis, we identified off-targets of gefitinib that might explain side effects of this drugs. The crystal structure of EGFR-gefitinib complex was used for binding pocket similarity searches on a druggable proteome database (Sc-PDB) by using IsoMIF Finder. The top 128 hits of putative off-targets were validated by reverse docking approach. The results showed that identified off-targets have efficient binding with gefitinib. The identified human specific off-targets were confirmed and further analyzed for their links with biological process and clinical disease pathways using retrospective studies and literature mining, respectively. Noticeably, many of the identified off-targets in this study were reported in previous high-throughput screenings. Interestingly, the present study reveals that gefitinib may have positive effects in reducing brain and bone metastasis, and may be useful in defining novel gefitinib based treatment regime. We propose that a system wide approach could be useful during new drug development and to minimize side effect of the prospective drug.
KW - gefitinib
KW - side effects
KW - drug
KW - off-targets
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167621
VL - 6
IS - 33949
ER -
TY - JOUR
A1 - Vendelova, Emilia
A1 - de Lima, Jeferson Camargo
A1 - Lorenzatto, Karina Rodrigues
A1 - Monteiro, Karina Mariante
A1 - Mueller, Thomas
A1 - Veepaschit, Jyotishman
A1 - Grimm, Clemens
A1 - Brehm, Klaus
A1 - Hrčková, Gabriela
A1 - Lutz, Manfred B.
A1 - Ferreira, Henrique B.
A1 - Nono, Justin Komguep
T1 - Proteomic Analysis of Excretory-Secretory Products of Mesocestoides corti Metacestodes Reveals Potential Suppressors of Dendritic Cell Functions
JF - PLoS Neglected Tropical Diseases
N2 - Accumulating evidences have assigned a central role to parasite-derived proteins in immunomodulation. Here, we report on the proteomic identification and characterization of immunomodulatory excretory-secretory (ES) products from the metacestode larva (tetrathyridium) of the tapeworm Mesocestoides corti (syn. M. vogae). We demonstrate that ES products but not larval homogenates inhibit the stimuli-driven release of the pro-inflammatory, Th1-inducing cytokine IL-12p70 by murine bone marrow-derived dendritic cells (BMDCs). Within the ES fraction, we biochemically narrowed down the immunosuppressive activity to glycoproteins since active components were lipid-free, but sensitive to heat- and carbohydrate-treatment. Finally, using bioassay-guided chromatographic analyses assisted by comparative proteomics of active and inactive fractions of the ES products, we defined a comprehensive list of candidate proteins released by M. corti tetrathyridia as potential suppressors of DC functions. Our study provides a comprehensive library of somatic and ES products and highlight some candidate parasite factors that might drive the subversion of DC functions to facilitate the persistence of M. corti tetrathyridia in their hosts.
KW - proteomic analysis
KW - excretory-secretory
KW - Mesocestoides corti
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166742
VL - 10
IS - 10
ER -
TY - JOUR
A1 - Vaze, Koustubh M.
A1 - Helfrich-Förster, Charlotte
T1 - Drosophila ezoana uses an hour-glass or highly damped circadian clock for measuring night length and inducing diapause
JF - Physiological Entomology
N2 - Insects inhabiting the temperate zones measure seasonal changes in day or night length to enter the overwintering diapause. Diapause induction occurs after the duration of the night exceeds a critical night length (CNL). Our understanding of the time measurement mechanisms is continuously evolving subsequent to Bünning’s proposal that circadian systems play the clock role in photoperiodic time measurement (Bünning, 1936). Initially, the photoperiodic clocks were considered to be either based on circadian oscillators or on simple hour-glasses, depending on ‘positive’ or ‘negative’ responses in Nanda–Hamner and Bünsow experiments (Nanda & Hammer, 1958; Bünsow, 1960).
However, there are also species whose responses can be regarded as neither ‘positive’, nor as ‘negative’, such as the Northern Drosophila species Drosophila ezoana, which is investigated in the present study. In addition, modelling efforts show that the ‘positive’ and ‘negative’ Nanda–Hamner responses can also be provoked by circadian oscillators that are damped to different degrees: animals with highly sustained circadian clocks will respond ‘positive’ and those with heavily damped circadian clocks will respond ‘negative’. In the present study, an experimental assay is proposed that characterizes the photoperiodic oscillators by determining the effects of non-24-h light/dark cycles (T-cycles) on critical night length. It is predicted that there is (i) a change in the critical night length as a function of T-cycle period in sustained-oscillator-based clocks and (ii) a fxed night-length measurement (i.e. no change in critical night length) in damped-oscillator-based clocks. Drosophila ezoana flies show a critical night length of approximately 7 h irrespective of T-cycle period, suggesting a damped-oscillator-based photoperiodic clock. The conclusion is strengthened by activity recordings revealing that the activity rhythm of D. ezoana flies also dampens in constant darkness.
KW - photoperiodic time mesurement
KW - wyeomyia smithii
KW - protophormia terraenovae
KW - immunoreactive neurons
KW - geographical variation
KW - reproductive diapause
KW - rhythmic components
KW - locomotor activity
KW - circadian clock
KW - damped-oscillator-model of photoperiodic clock
KW - diapause
KW - Drosophila
KW - hour-glass
KW - pitcher-plant mosquito
KW - bug riptortus-pedestris
KW - Nanda-Hamner
KW - photoperiodism
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-204278
VL - 41
IS - 4
ER -
TY - THES
A1 - Vasquez Ospina, Juan Jose
T1 - Development of tools for the study of gene regulation in Trypanosoma brucei
T1 - Entwicklung neuer Methoden zur Untersuchung der Genregulation in Trypanosoma brucei
N2 - The protozoan parasite Trypanosoma brucei is the causal agent of sleeping sickness and besides its epidemiological importance it has been used as model organism for the study of many aspects of cellular and molecular biology especially the post-transcriptional control of gene expression.
Several studies in the last 30 years have shown the importance of mRNA processing and stability for gene regulation. In T. brucei genes are unusually arranged in polycistronic transcription units (PTUs) and a coupled process of trans-splicing and polyadenylation produces the mature mRNAs. Both processes, mRNA processing and stability, cannot completely explain the control of gene expression in the different life cycle stages analyzed in T. brucei so far.
In recent years, the relevance of expression regulation at the level of translation has become evident in other eukaryotes. Therefore, in the first part of my thesis I studied the impact of translational regulation by means of a genome-wide ribosome profiling approach. My data suggest that translational efficiencies vary between life cycle stages of the parasite as well as between genes within one life cycle stage. Furthermore, using ribosome profiling I was able to identify many new putative un-annotated coding sequences and to evaluate the coding potential of upstream open reading frames (uORF). Comparing my results with previously published proteomic and RNA interference (RNAi) target sequencing (RIT-seq) datasets allowed me to validate some of the new coding sequences and to evaluate their relevance for the fitness of the parasite.
In the second part of my thesis I used the transcriptomic and translatomic profiles obtained from the ribosome profiling analysis for the identification of putative non-coding RNAs (ncRNAs). These results led to the analysis of the coding potential in the regions upstream and downstream of the expressed variant surface glycoprotein (VSG), which is outlined in the third part of the results section. The region upstream of the VSG, the co-transposed region (CTR), has been implicated in an increase of the in situ switching rate upon its deletion. The ribosome profiling results indicated moderate transcription but not translation in this region. These results raised the possibility that the CTR may be transcribed into ncRNA. Therefore, in the third part of my thesis, I performed a primary characterization of the CTR-derived transcripts based on northern blotting and RACE. The results suggested the presence of a unique transcript species of about 1,200 nucleotides (nt) and polyadenylated at the 3’-end of the sequence.
The deletion of the CTR sequence promoting and increase of the in situ switching rates was performed around 20 years ago by means of inserting reporter genes. With the recent development of endonuclease-based tools for genome editing, it is now possible to delete sequences in a marker-free way. In the fourth part of my thesis, I show the results on the implementation of the highly efficient genome-editing CRISPR-Cas9 system in T. brucei using episomes. As a proof of principle, I inserted the sequence coding for the enhanced green fluorescent protein (eGFP) at the end of the SCD6 coding sequence (CDS). Fluorescent cells were observed as early as two days after transfection. Therefore, after the successful set up of the CRISPR-Cas9 system it will be possible to modify genomic regions with more relevance for the biology of the parasite, such as the substitution of codons present in gene tandem arrays.
The implementation of ribosome profiling in T. brucei opens the opportunity for the study of translational regulation in a genome-wide scale, the re-annotation of the currently available genome, the search for new putative coding sequences, the detection of putative ncRNAs, the evaluation of the coding potential in uORFs and the role of unstranslated regions (UTRs) in the regulation of translation. In turn, the implementation of the CRISPR-Cas9 system offers the possibility to manipulate the genome of the parasite at a nucleotide resolution and without the need of including resistant makers. The CRISPR-Cas9 system is a powerful tool for editing ncRNAs, UTRs, multicopy gene families and CDSs keeping their endogenous UTRs. Moreover, the system can be used for the modification of both alleles after just one round of transfection and of codons coding for amino acids carrying post-translational modifications (PTMs) among other possibilities.
N2 - Trypanosoma brucei ist nicht nur als Erreger der Schlafkrankheit von großer epidemiologischer Bedeutung, sondern dient auch der Zell-‐ und Molekularbiologie – insbesondere zur Erforschung der Genregulation auf posttranskriptionaler Ebene – als wichtiger Modellorganismus.
In den vergangenen 30 Jahren konnten mehrere Forschungsarbeiten zeigen, dass mRNA-‐Stabilität und –Prozessierung maßgeblich zur Regulation der Genexpression beitragen. Anders als in den meisten Eukaryoten sind die Gene in
T. brucei in polycistronischen Transkriptionseinheiten (PTUs) angeordnet. Die reife mRNA entsteht aus dem polycistronischen Transkript in einem gekoppelten Prozess aus Trans-‐splicing und paralleler Polyadenylierung.
Beide Vorgänge allein, mRNA-‐Stabilität und –Prozessierung, reichen nicht aus, um die Regulation der Genexpression in T. brucei vollständing zu erklären und zusätzliche Mechanismen müssen wirksam sein.
Daher habe ich im ersten Teil meiner hier vorliegenden Doktorarbeit die Genregulation auf Ebene der Translation mittels genomweitem Ribosome Profiling untersucht. Die dabei gewonnen Daten deuten darauf hin, dass die Translationseffizienzen nicht nur zwischen prozyklischen-‐ und Blutstromformen des Parasiten differieren, sondern auch die Gene innerhalb eines Stadiums verschieden effizient translatiert werden. Zudem war es mir mit diesem Ansatz
möglich, neue, noch nicht annotierte kodierende Sequenzen zu identifizieren und das Kodierungspotenzial der jeweils vorgelagerten offenen Leseraster (ORFs) zu evaluieren. Mithilfe bereits veröffentlichter Proteom-‐ und RNA Interferenz-‐ Studien (RIT-‐seq) konnte ich einige der neu identifizierten kodierenden Sequenzen validieren und deren Bedeutung für die Fitness des Parasiten bestimmen.
Im zweiten Teil der Arbeit wurden die ermittelten Translations-‐ und Transkriptionsprofile miteinander verglichen, um auf diese Weise mögliche nicht-‐kodierende RNAs (ncRNAs) zu identifizieren. Dies führte zu einer eingehenderen Betrachtung der Kodierungspotenziale der dem exprimierten variablen Oberflächenproteins (VSG) vor-‐ und nachgeschalteten Regionen. In früheren Arbeiten wurde bereits beschrieben, dass eine Deletion der dem VSG vorgelagerten, sogenannten co-‐transposed region (CTR), vermehrt zu einer Aktivierung einer alternativen VSG Expressionsseite (in situ switches) führt. Ribosome Profiling zeigte, dass eben jede Regionen zwar moderat transkribiert, jedoch nicht translatiert werden. Da diese Ergebnisse vermuten ließen, dass die CTR für eine ncRNA kodiert, hab ich im dritten Teil meiner Arbeit die CTR Transkripte mittels Northern Blot und RACE weiter charakterisiert. Auf diese Weise konnte ich spezifische, 1200 Nukleotide (nt) lange und am 3`-‐Ende polyadenylierte Transkripte nachweisen.
Die bereits erwähnte Deletion der CTR verbunden mit einer erhöhten Rate an in situ switches wurde vor etwa 20 Jahren durch Insertion von Reportergenen durchgeführt. Heute ist es möglich mithilfe von Endonukleasen Genome ohne solche Marker zu editieren. So beschreibt der vierte Teil der Arbeit
die Konstruktion von Episomen zur Etablierung und Anwendung des CRISPR-‐ Cas9 Systems in T. brucei. Als Machbarkeitsnachweis wurde die kodierende Sequenz des grün fluoreszierenden Proteins (eGFP) am Ende des SCD6 Gens als Fusionsprotein inseriert. Grün fluoreszierende Zellen konnten bereits zwei Tage nach der Transfektion nachgewiesen werden. Nachdem CRISPR-‐Cas9 erfolgreich in T. brucei etabliert werden konnte, werde ich im Folgenden weitere relevante Regionen im Genom modifizieren und beispielsweise die Deletion zweier Histonvarianten durchführen.
Die Ribosome Profiling Studie in T. brucei erlaubt es uns, genomweit Genregulation auf Ebene der Translation zu analysieren, das uns zurzeit vorliegende Genom zu re-‐annotieren, neue kodierende Sequenzen wie auch ncRNAs zu identifizieren und den Einfluss nicht-‐kodierender Sequenzen auf die Translation zu untersuchen. Gleichzeitig ermöglicht die Etablierung des CRISPR-‐ Cas9 Systems in T. brucei eine hochpräzise Manipulation des Genoms ohne den Einsatz von Resistenzmarkern. Auf diese Weise ist es möglich, Gene zu modifizieren und dabei die zugehörigen untranslatierten Bereiche (UTRs) zu erhalten, aber auch ncRNAs, UTRs und mehrfache Kopien eines Gens (gleichzeitig) zu editieren. Ebenso können einzelne Kodons in der Sequenz und somit posttranslational modifizierte Aminosäuren im Genprodukt verändert werden, was uns weitere Möglichkeiten zur Erforschung der Genregulation eröffnet.
KW - Trypanosoma brucei
KW - Ribosom
KW - Posttranskriptionelle Regulation
KW - Trypanosoma brucei
KW - Gene expression regulation
KW - Ribosome profiling
KW - CRISPR Cas9
KW - CRISPR Cas9 system
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133996
ER -
TY - JOUR
A1 - van Unen, Jakobus
A1 - Stumpf, Anette D.
A1 - Schmid, Benedikt
A1 - Reinhard, Nathalie R.
A1 - Hordijk, Peter L.
A1 - Hoffmann, Carsten
A1 - Gadella, Theodorus W. J.
A1 - Goedhart, Joachim
T1 - A New Generation of FRET Sensors for Robust Measurement of Gα\(_{i1}\), Gα\(_{i2}\) and Gα\(_{i3}\) Activation Kinetics in Single Cells
JF - PLoS ONE
N2 - G-protein coupled receptors (GPCRs) can activate a heterotrimeric G-protein complex with subsecond kinetics. Genetically encoded biosensors based on Förster resonance energy transfer (FRET) are ideally suited for the study of such fast signaling events in single living cells. Here we report on the construction and characterization of three FRET biosensors for the measurement of Gα\(_{i1}\), Gα\(_{i2}\) and Gα\(_{i3}\) activation. To enable quantitative long-term imaging of FRET biosensors with high dynamic range, fluorescent proteins with enhanced photophysical properties are required. Therefore, we use the currently brightest and most photostable CFP variant, mTurquoise2, as donor fused to Gα\(_{i}\) subunit, and cp173Venus fused to the Gγ\(_{2}\) subunit as acceptor. The Gα\(_{i}\) FRET biosensors constructs are expressed together with Gβ\(_{1}\) from a single plasmid, providing preferred relative expression levels with reduced variation in mammalian cells. The Gα\(_{i}\) FRET sensors showed a robust response to activation of endogenous or over-expressed alpha-2A-adrenergic receptors, which was inhibited by pertussis toxin. Moreover, we observed activation of the Gα\(_{i}\) FRET sensor in single cells upon stimulation of several GPCRs, including the LPA\(_{2}\), M\(_{3}\) and BK\(_{2}\) receptor. Furthermore, we show that the sensors are well suited to extract kinetic parameters from fast measurements in the millisecond time range. This new generation of FRET biosensors for Gα\(_{i1}\), Gα\(_{i2}\) and Gα\(_{i3}\) activation will be valuable for live-cell measurements that probe Gα\(_{i}\) activation.
KW - FRET sensors
KW - G-protein coupled receptors
KW - Förster resonance energy transfer
KW - Gα\(_{i1}\), Gα\(_{i2}\) and Gα\(_{i3}\) activation
KW - biosensors
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167387
VL - 11
IS - 1
ER -
TY - JOUR
A1 - van Toor, Mariëlle L.
A1 - Newman, Scott H.
A1 - Takekawa, John Y.
A1 - Wegmann, Martin
A1 - Safi, Kamran
T1 - Temporal segmentation of animal trajectories informed by habitat use
JF - Ecosphere
N2 - Most animals live in seasonal environments and experience very different conditions throughout the year. Behavioral strategies like migration, hibernation, and a life cycle adapted to the local seasonality help to cope with fluctuations in environmental conditions. Thus, how an individual utilizes the environment depends both on the current availability of habitat and the behavioral prerequisites of the individual at that time. While the increasing availability and richness of animal movement data has facilitated the development of algorithms that classify behavior by movement geometry, changes in the environmental correlates of animal movement have so far not been exploited for a behavioral annotation. Here, we suggest a method that uses these changes in individual–environment associations to divide animal location data into segments of higher ecological coherence, which we term niche segmentation. We use time series of random forest models to evaluate the transferability of habitat use over time to cluster observational data accordingly. We show that our method is able to identify relevant changes in habitat use corresponding to both changes in the availability of habitat and how it was used using simulated data, and apply our method to a tracking data set of common teal (Anas crecca). The niche segmentation proved to be robust, and segmented habitat suitability outperformed models neglecting the temporal dynamics of habitat use. Overall, we show that it is possible to classify animal trajectories based on changes of habitat use similar to geometric segmentation algorithms. We conclude that such an environmentally informed classification of animal trajectories can provide new insights into an individuals' behavior and enables us to make sensible predictions of how suitable areas might be connected by movement in space and time.
KW - Anas crecca
KW - animal movement
KW - common teal
KW - habitat use
KW - life history
KW - migration
KW - niche dynamics
KW - random forest models
KW - segmentation
KW - simulation
KW - species distribution model
KW - transferability
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164970
VL - 7
IS - 10
ER -
TY - JOUR
A1 - Van Haute, Lindsey
A1 - Dietmann, Sabine
A1 - Kremer, Laura
A1 - Hussain, Shobbir
A1 - Pearce, Sarah F.
A1 - Powell, Christopher A.
A1 - Rorbach, Joanna
A1 - Lantaff, Rebecca
A1 - Blanco, Sandra
A1 - Sauer, Sascha
A1 - Kotzaeridou, Urania
A1 - Hoffmann, Georg F.
A1 - Memari, Yasin
A1 - Kolb-Kokocinski, Anja
A1 - Durbin, Richard
A1 - Mayr, Johannes A.
A1 - Frye, Michaela
A1 - Prokisch, Holger
A1 - Minczuk, Michal
T1 - Deficient methylation and formylation of mt-tRNA(Met) wobble cytosine in a patient carrying mutations in NSUN3
JF - Nature Communications
N2 - Epitranscriptome modifications are required for structure and function of RNA and defects in these pathways have been associated with human disease. Here we identify the RNA target for the previously uncharacterized 5-methylcytosine (m5C) methyltransferase NSun3 and link m5C RNA modifications with energy metabolism. Using whole-exome sequencing, we identified loss-of-function mutations in NSUN3 in a patient presenting with combined mitochondrial respiratory chain complex deficiency. Patient-derived fibroblasts exhibit severe defects in mitochondrial translation that can be rescued by exogenous expression of NSun3. We show that NSun3 is required for deposition of m5C at the anticodon loop in the mitochondrially encoded transfer RNA methionine (mt-tRNAMet). Further, we demonstrate that m5C deficiency in mt-tRNAMet results in the lack of 5-formylcytosine (f5C) at the same tRNA position. Our findings demonstrate that NSUN3 is necessary for efficient mitochondrial translation and reveal that f5C in human mitochondrial RNA is generated by oxidative processing of m5C.
KW - Methylation
KW - RNA
KW - Transferases
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165998
VL - 7
ER -
TY - JOUR
A1 - van de Kerkhof, Nora WA
A1 - Fekkes, Durk
A1 - van der Heijden, Frank MMA
A1 - Hoogendijk, Witte JG
A1 - Stöber, Gerald
A1 - Egger, Jos IM
A1 - Verhoeven, Willem MA
T1 - Cycloid psychoses in the psychosis spectrum: evidence for biochemical differences with schizophrenia
JF - Neuropsychiatric Disease and Treatment
N2 - Cycloid psychoses (CP) differ from schizophrenia regarding symptom profile, course, and prognosis and over many decades they were thought to be a separate entity within the psychosis spectrum. As to schizophrenia, research into the pathophysiology has focused on dopamine, brain-derived neurotrophic factor, and glutamate signaling in which, concerning the latter, the N-methyl-d-aspartate receptor plays a crucial role. The present study aims to determine whether CP can biochemically be delineated from schizophrenia. Eighty patients referred for psychotic disorders were assessed with the Comprehensive Assessment of Symptoms and History, and (both at inclusion and after 6 weeks of antipsychotic treatment) with the Positive and Negative Syndrome Scale and Clinical Global Impression. From 58 completers, 33 patients were diagnosed with schizophrenia and ten with CP according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and Leonhard criteria, respectively. Fifteen patients were diagnosed with other disorders within the psychosis spectrum. At both time points, blood levels of the dopamine metabolite homovanillic acid, brain-derived neurotrophic factor, and amino acids related to glutamate neurotransmission were measured and compared with a matched control sample. Patients with CP showed a significantly better response to antipsychotic treatment as compared to patients with schizophrenia. In CP, glycine levels were elevated and tryptophan levels were lowered as compared to schizophrenia. Glutamate levels were increased in both patient groups as compared to controls. These results, showing marked differences in both treatment outcome and glutamate-related variable parameters, may point at better neuroplasticity in CP, necessitating demarcation of this subgroup within the psychosis spectrum.
KW - cycloid psychoses
KW - schizophrenia
KW - glutamate
KW - glycine
KW - tryptophan
KW - neuroplasticity
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166255
VL - 12
ER -
TY - JOUR
A1 - Vaiopoulos, Aristeidis G.
A1 - Kanakis, Meletios A.
A1 - Kapsimali, Violetta
A1 - Vaiopoulos, Georgios
A1 - Kaklamanis, Phedon G.
A1 - Zouboulis, Christos C.
T1 - Juvenile Adamantiades-Behçet disease
JF - Dermatology
N2 - Adamantiades-Behçet disease (ABD) is a chronic, multisystemic, recurrent, inflammatory vascular disorder of unknown etiology. Patients with symptoms initially appearing at the age of 16 or less are considered as cases of juvenile-onset ABD (JABD). JABD is relatively rare compared to ABD of adults, and only case reports and case studies have been published regarding this subtype of the disease. Epidemiology, clinical features, diagnosis and treatment of JABD are discussed in this review.
KW - Aphthae
KW - Childhood
KW - Epidemiological study
KW - Genitoanal region
KW - Adamantiades-Behçet disease
KW - Behçet’s disease
KW - Uveitis
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-196616
SN - 1018-8665
SN - 1421-9832
N1 - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.
VL - 232
IS - 2
SP - 129
EP - 136
ER -
TY - THES
A1 - Ulrich, Natalie
T1 - Processing of Near Outcomes and Outcome Sequences in Gambling: Implications for the Biopsychological Basis of Problem Gambling
T1 - Verarbeitung von knappen Ergebnissen und Ergebnissequenzen im Glücksspiel : Implikationen für die biopsychologische Basis von problematischem Glücksspielverhalten
N2 - Gambling is a popular activity in Germany, with 40% of a representative sample reporting having gambled at least once in the past year (Bundeszentrale für gesundheitliche Aufklärung, 2014). While the majority of gamblers show harmless gambling behavior, a subset develops serious problems due to their gambling, affecting their psychological well-being, social life and work. According to recent estimates, up to 0.8% of the German population are affected by such pathological gambling. People in general and pathological gamblers in particular show several cognitive distortions, that is, misconceptions about the chances of winning and skill involvement, in gambling. The current work aimed at elucidating the biopsychological basis of two such kinds of cognitive distortions, the illusion of control and the gambler’s and hot hand fallacies, and their modulation by gambling problems. Therefore, four studies were conducted assessing the processing of near outcomes (used as a proxy for the illusion of control) and outcome sequences (used as a proxy for the gambler’s and hot hand fallacies) in samples of varying degrees of gambling problems, using a multimethod approach.
The first study analyzed the processing and evaluation of near outcomes as well as choice behavior in a wheel of fortune paradigm using electroencephalography (EEG). To assess the influence of gambling problems, a group of problem gamblers was compared to a group of controls. The results showed that there were no differences in the processing of near outcomes between the two groups. Near compared to full outcomes elicited smaller P300 amplitudes. Furthermore, at a trend level, the choice behavior of participants showed signs of a pattern opposite to the gambler’s fallacy, with longer runs of an outcome color leading to increased probabilities of choosing this color again on the subsequent trial. Finally, problem gamblers showed smaller feedback-related negativity (FRN) amplitudes relative to controls.
The second study also targeted the processing of near outcomes in a wheel of fortune paradigm, this time using functional magnetic resonance imaging and a group of participants with varying degrees of gambling problems. The results showed increased activity in the bilateral superior parietal cortex following near compared to full outcomes.
The third study examined the peripheral physiology reactions to near outcomes in the wheel of fortune. Heart period and skin conductance were measured while participants with varying degrees of gambling problems played on the wheel of fortune. Near compared to full outcomes led to increased heart period duration shortly after the outcome. Furthermore, heart period reactions and skin conductance responses (SCRs) were modulated by gambling problems. Participants with high relative to low levels of gambling problems showed increased SCRs to near outcomes and similar heart period reactions to near outcomes and full wins.
The fourth study analyzed choice behavior and sequence effects in the processing of outcomes in a coin toss paradigm using EEG in a group of problem gamblers and controls. Again, problem gamblers showed generally smaller FRN amplitudes compared to controls. There were no differences between groups in the processing of outcome sequences. The break of an outcome streak led to increased power in the theta frequency band. Furthermore, the P300 amplitude was increased after a sequence of previous wins. Finally, problem gamblers compared to controls showed a trend of switching the outcome symbol relative to the previous outcome symbol more often.
In sum, the results point towards differences in the processing of near compared to full outcomes in brain areas and measures implicated in attentional and salience processes. The processing of outcome sequences involves processes of salience attribution and violation of expectations. Furthermore, problem gamblers seem to process near outcomes as more win-like compared to controls. The results and their implications for problem gambling as well as further possible lines of research are discussed.
N2 - Glücksspiel ist eine verbreitete Aktivität in Deutschland. 40% einer repräsentativen Stichprobe gaben an mindestens einmal im vergangenen Jahr um Geld gespielt zu haben (Bundeszentrale für gesundheitliche Aufklärung, 2014). Während die Mehrheit der Glücksspieler unbedenkliches Spielverhalten zeigt, entwickelt ein Teil der Spieler ernsthafte Probleme durch das Spielen, die das psychische Wohlergehen, sowie das soziale und Arbeitsleben beeinträchtigen. Nach aktuellen Schätzungen sind bis zu 0,8% der deutschen Bevölkerung von solch pathologischem Glücksspielen betroffen. Generell zeigen Menschen verschiedene kognitive Verzerrungen im Sinne falscher Einschätzungen der Gewinnwahrscheinlichkeit und der Beteiligung von Fähigkeiten in Bezug auf Glücksspiel. Dies trifft insbesondere für pathologische Glücksspieler zu. Das Ziel der vorliegenden Arbeit ist die Untersuchung der biopsychologischen Grundlagen zweier solcher kognitiver Verzerrungen, der Kontrollillusion sowie der Gambler’s Fallacy (bisweilen auch Spielerfehlschluss genannt) und Hot-Hand-Phänomene, sowie deren Modulation durch Glücksspielprobleme. Zu diesem Zweck wurden vier Studien durchgeführt, die die Verarbeitung knapper Ergebnisse (stellvertretend für die Kontrollillusion) und Ergebnissequenzen (stellvertretend für die Phänomene der Gambler’s Fallacy und Hot Hand) untersuchten. Dazu wurden Stichproben mit unterschiedlichem Schweregrad der Glücksspielproblematik sowie ein Multi-Methoden Ansatz verwendet.
Die erste Studie untersuchte die Verarbeitung und Bewertung knapper Ergebnisse sowie das Wahlverhalten in einem Glücksrad Paradigma mittels Elektroenzephalographie (EEG). Um den Einfluss der Glücksspielproblematik zu erfassen, wurde eine Gruppe von Problemspielern mit einer Kontrollgruppe verglichen. Es zeigten sich keine Unterschiede in der Verarbeitung knapper Ergebnisse zwischen den beiden Gruppen. Im Vergleich zu vollen Ergebnissen führten knappe Ergebnisse zu kleineren Amplituden in der P300. Des Weiteren zeigte sich auf Trendniveau im Wahlverhalten der Probanden Anzeichen für ein der Gambler’s Fallacy entgegengesetztes Muster. Längere Sequenzen einer Ergebnisfarbe führten zu einer höheren Wahrscheinlichkeit diese Farbe im folgenden Durchgang erneut zu wählen. Schließlich zeigten Problemspieler relativ zur Kontrollgruppe kleinere Amplituden in der Feedbacknegativierung (FRN).
Die zweite Studie zielte ebenfalls auf die Verarbeitung knapper Ergebnisse im Glücksrad Paradigma ab, allerdings unter Verwendung funktioneller Magnetresonanztomographie sowie einer Probandengruppe mit variierendem Ausmaß der Glücksspielproblematik. Es zeigte sich eine verstärkte Aktivierung im bilateralen superioren parietalen Cortex nach knappen im Vergleich zu vollen Ergebnissen.
Die dritte Studie untersuchte peripherphysiologische Reaktionen auf knappe Ergebnisse im Glücksrad. Hierzu wurden Herzperiode und Hautleitfähigkeit erfasst während eine Probandengruppe mit unterschiedlichem Ausmaß an Glücksspielproblemen am Glücksrad spielte. Knappe Ergebnisse führten im Vergleich zu vollen Ergebnissen zu verlängerten Herzperioden kurz nach dem Ergebnis. Des Weiteren wurden die Herzperiodenreaktion und Hautleitfähigkeitsreaktion durch Glücksspielprobleme moduliert. Probanden mit einem hohem im Vergleich zu einem niedrigen Ausmaß an Glücksspielproblemen zeigten gesteigerte Hautleitfähigkeitsreaktionen auf knappe im Vergleich zu vollen Ergebnissen, sowie ähnliche Herzperiodenreaktionen auf knappe Ergebnisse und volle Gewinne.
Die vierte Studie untersuchte das Wahlverhalten sowie Einflüsse vorheriger Sequenzen auf die Verarbeitung von Ergebnissen in einem Münzwurf Paradigma. Hierzu wurde ein EEG bei einer Gruppe von Problemspielern und Kontrollprobanden abgeleitet. Problemspieler zeigten wiederum generell kleinere FRN Amplituden als Kontrollen. Es zeigten sich keine Unterschiede in der Verarbeitung der Ergebnissequenzen zwischen den Gruppen. Die Unterbrechung einer Sequenz gleicher Ergebnisse führte zu verstärkter Power im Theta Frequenzband. Zusätzlich war die Amplitude der P300 nach zwei vorangegangenen Gewinnen erhöht. Schließlich zeigten Problemspieler im Vergleich zu Kontrollen die Tendenz das gewählte Symbol relativ zum vorangegangenen Ergebnissymbol häufiger zu wechseln.
Zusammenfassend deuten die Ergebnisse auf Unterschiede in der Verarbeitung knapper und voller Ergebnisse hin, die vor allem Gehirnareale und Prozesse umfassen, die mit Aufmerksamkeit und Salienz assoziiert sind. Die Verarbeitung von Ergebnissequenzen umfasst Prozesse der Salienzzuschreibung und Erwartungsverletzung. Außerdem scheinen Problemspieler im Vergleich zu Kontrollen knappe Ergebnisse als gewinnähnlicher zu verarbeiten. Die Ergebnisse und deren Implikationen für problematisches Glücksspielverhalten sowie weitere mögliche Forschungsfragen werden diskutiert.
KW - Spielsucht
KW - Psychobiologie
KW - Near Miss
KW - Problem Gambling
KW - Heart Period
KW - EEG
KW - fMRI
KW - Gambler's Fallacy
KW - Hot Hand Fallacy
KW - Cognitive Distortions
KW - Glücksspiel
KW - Electroencephalographie
KW - Funktionelle Kernspintomografie
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-139612
ER -
TY - JOUR
A1 - Ullmann, Tobias
A1 - Schmitt, Andreas
A1 - Jagdhuber, Thomas
T1 - Two Component Decomposition of Dual Polarimetric HH/VV SAR Data: Case Study for the Tundra Environment of the Mackenzie Delta Region, Canada
JF - Remote Sensing
N2 - This study investigates a two component decomposition technique for HH/VV-polarized PolSAR (Polarimetric Synthetic Aperture Radar) data. The approach is a straight forward adaption of the Yamaguchi decomposition and decomposes the data into two scattering contributions: surface and double bounce under the assumption of a negligible vegetation scattering component in Tundra environments. The dependencies between the features of this two and the classical three component Yamaguchi decomposition were investigated for Radarsat-2 (quad) and TerraSAR-X (HH/VV) data for the Mackenzie Delta Region, Canada. In situ data on land cover were used to derive the scattering characteristics and to analyze the correlation among the PolSAR features. The double bounce and surface scattering features of the two and three component scattering model (derived from pseudo-HH/VV- and quad-polarized data) showed similar scattering characteristics and positively correlated-R2 values of 0.60 (double bounce) and 0.88 (surface scattering) were observed. The presence of volume scattering led to differences between the features and these were minimized for land cover classes of low vegetation height that showed little volume scattering contribution. In terms of separability, the quad-polarized Radarsat-2 data offered the best separation of the examined tundra land cover types and will be best suited for the classification. This is anticipated as it represents the largest feature space of all tested ones. However; the classes “wetland” and “bare ground” showed clear positions in the feature spaces of the C- and X-Band HH/VV-polarized data and an accurate classification of these land cover types is promising. Among the possible dual-polarization modes of Radarsat-2 the HH/VV was found to be the favorable mode for the characterization of the aforementioned tundra land cover classes due to the coherent acquisition and the preserved co-pol. phase. Contrary, HH/HV-polarized and VV/VH-polarized data were found to be best suited for the characterization of mixed and shrub dominated tundra.
KW - Synthetic Aperture Radar (SAR)
KW - Polarimetric Synthetic Aperture Radar (PolSAR)
KW - polarimetric decomposition
KW - Radarsat-2
KW - arctic
KW - Canada
KW - tundra
KW - TerraSAR-X
KW - dual polarimetry
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147879
VL - 8
IS - 12
ER -
TY - JOUR
A1 - Ullmann, Tobias
A1 - Büdel, Christian
A1 - Baumhauer, Roland
A1 - Padashi, Majid
T1 - Sentinel-1 SAR Data Revealing Fluvial Morphodynamics in Damghan (Iran): Amplitude and Coherence Change Detection
JF - International Journal of Earth Science and Geophysics
N2 - The Sentinel-1 Satellite (S-1) of ESA's Copernicus Mission delivers freely available C-Band Synthetic Aperture Radar (SAR) data that are suited for interferometric applications (InSAR). The high geometric resolution of less than fifteen meter and the large coverage offered by the Interferometric Wide Swath mode (IW) point to new perspectives on the comprehension and understanding of surface changes, the quantification and monitoring of dynamic processes, especially in arid regions. The contribution shows the application of S-1 intensities and InSAR coherences in time series analysis for the delineation of changes related to fluvial morphodynamics in Damghan, Iran. The investigations were carried out for the period from April to October 2015 and exhibit the potential of the S-1 data for the identification of surface disturbances, mass movements and fluvial channel activity in the surroundings of the Damghan Playa. The Amplitude Change Detection highlighted extensive material movement and accumulation - up to sizes of more than 4,000 m in width - in the east of the Playa via changes in intensity. Further, the Coherence Change Detection technique was capable to indicate small-scale channel activity of the drainage system that was neither recognizable in the S-1 intensity nor the multispectral Landsat-8 data. The run off caused a decorrelation of the SAR signals and a drop in coherence. Seen from a morphodynamic point of view, the results indicated a highly dynamic system and complex tempo-spatial patterns were observed that will be subject of future analysis. Additionally, the study revealed the necessity to collect independent reference data on fluvial activity in order to train and adjust the change detector.
KW - SAR
KW - InSAR
KW - coherence
KW - Iran
KW - Sentinel-1
KW - radar
KW - geomorphology
KW - change detection
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147863
VL - 2
IS - 1
ER -
TY - JOUR
A1 - Ullmann, Andrew J.
A1 - Schmidt-Hieber, Martin
A1 - Bertz, Hartmut
A1 - Heinz, Werner J.
A1 - Kiehl, Michael
A1 - Krüger, William
A1 - Mousset, Sabine
A1 - Neuburger, Stefan
A1 - Neumann, Silke
A1 - Penack, Olaf
A1 - Silling, Gerda
A1 - Vehreschild, Jörg Janne
A1 - Einsele, Hermann
A1 - Maschmeyer, Georg
T1 - Infectious diseases in allogeneic haematopoietic stem cell transplantation: prevention and prophylaxis strategy guidelines 2016
JF - Annals of Hematology
N2 - Infectious complications after allogeneic haematopoietic stem cell transplantation (allo-HCT) remain a clinical challenge. This is a guideline provided by the AGIHO (Infectious Diseases Working Group) of the DGHO (German Society for Hematology and Medical Oncology). A core group of experts prepared a preliminary guideline, which was discussed, reviewed, and approved by the entire working group. The guideline provides clinical recommendations for the preventive management including prophylactic treatment of viral, bacterial, parasitic, and fungal diseases. The guideline focuses on antimicrobial agents but includes recommendations on the use of vaccinations. This is the updated version of the AGHIO guideline in the field of allogeneic haematopoietic stem cell transplantation utilizing methods according to evidence-based medicine criteria.
KW - Bone-marrow-transplantation
KW - Pneumocystis-carinii-pneumonia
KW - Influenzae type B
KW - Respiratory syncytial virus
KW - Infections
KW - invasive fungal infections
KW - Varicella-Zoster-Virus
KW - Hepatitis B virus
KW - Herpes simplex virus
KW - Human immunodefiency virus
KW - Low-dose acyclovir
KW - Viral
KW - Fungal
KW - Bacteria
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187587
VL - 95
IS - 9
ER -
TY - JOUR
A1 - Türp, Jens C.
A1 - Schlenker, Anna
A1 - Schröder, Johannes
A1 - Essig, Marco
A1 - Schmitter, Marc
T1 - Disk displacement, eccentric condylar position, osteoarthrosis - misnomers for variations of normality? Results and interpretations from an MRI study in two age cohorts
JF - BMC Oral Health
N2 - Background
Clinical decision-making and prognostic statements in individuals with manifest or suspected temporomandibular disorders (TMDs) may involve assessment of (a) the position of articular disc relative to the mandibular condyle, (b) the location of the condyle relative to the temporal joint surfaces, and (c) the depth of the glenoid fossa of the temporomandibular joints (TMJs). The aim of this study was twofold: (1) Determination of the prevalence of these variables in two representative population-based birth cohorts. (2) Reinterpretation of the clinical significance of the findings.
Methods
From existing magnetic resonance imaging (MRI) scans of the TMJs that had been taken in 2005 and 2006 from 72 subjects born between 1930 and 1932 and between 1950 and 1952, respectively, the condylar position at closed jaw was calculated as percentage displacement of the condyle from absolute centricity. By using the criteria introduced by Orsini et al. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 86:489-97, 1998), a textbook-like disc position at closed jaw was distinguished from an anterior location. TMJ morphology of the temporal joint surfaces was assessed at open jaw by measuring the depth of the glenoid fossa, using the method proposed by Muto et al. (J Oral Maxillofac Surg 52:1269-72, 1994).
Frequency distributions were recorded for the condylar and disc positions at closed jaw.
Student’s t-test with independent samples was used as test of significance to detect differences of condylar positions between the age cohorts (1930 vs. 1950) and the sexes. The significance levels were set at 5%. First, the results from the measurement of the age cohorts were compared without differentiation of sexes, i.e., age cohort 1930–1932 versus age cohort 1950–1952. Subsequently, the age cohorts were compared by sex, i.e., men in cohort 1930–1932 versus men in cohort 1950–1952, and women in cohort 1930–1932 women men in cohort 1950–1952.
Results
In both cohorts, condylar position was characterized by great variability. About 50% of the condyles were located centrically, while the other half was either in an anterior or in a posterior position. In both female cohorts, a posterior position predominated, whereas a centric position prevailed among men. Around 75% of the discs were positioned textbook-like, while the remaining forth was located anteriorly. Age had no statistically significant influence on condylar or on disc position. Conversely, comparison between the age groups revealed a statistically significant decrease of the depth of the glenoid fossa in both older cohorts. This age-dependent changes may be interpreted as flattening of the temporal joint surfaces.
Conclusions
We call for a re-interpretation of imaging findings because they may insinuate pathology which usually is not present. Instead, anterior or posterior positions of the mandibular condyle as well as an anterior location of the articular disc should be construed as a variation of normalcy. Likewise, flattening of articular surfaces of the TMJs may be considered as normal adaptive responses to increased loading, rather than pathological degenerative changes.
KW - Image interpretation
KW - Medicalization
KW - Osteoarthritis
KW - Overdiagnosis
KW - Temporomandibular joint disc
KW - Mandibular condyle
KW - Medical overuse
KW - Osteoarthrosis
KW - Temporomandibular disorders
KW - Terminology
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164710
VL - 16
IS - 124
ER -
TY - JOUR
A1 - Tsiligianni, Ioanna G.
A1 - Alma, Harma J.
A1 - Kocks, Janwillem W. H.
A1 - de Jong, Corina
A1 - Jelusic, Danijel
A1 - Wittmann, Michael
A1 - Schuler, Michael
A1 - Schultz, Konrad
A1 - Kollen, Boudewijn J.
A1 - van der Molen, Thys
T1 - Investigating sensitivity, specificity, and area under the curve of the Clinical COPD Questionnaire, COPD Assessment Test, and Modified Medical Research Council scale according to GOLD using St George's Respiratory Questionnaire cutoff 25 (and 20) as reference
JF - International Journal of COPD
N2 - Background: In the GOLD (Global initiative for chronic Obstructive Lung Disease) strategy document, the Clinical COPD Questionnaire (CCQ), COPD Assessment Test (CAT), or modified Medical Research Council (mMRC) scale are recommended for the assessment of symptoms using the cutoff points of CCQ ≥1, CAT ≥10, and mMRC scale ≥2 to indicate symptomatic patients. The current study investigates the criterion validity of the CCQ, CAT and mMRC scale based on a reference cutoff point of St George’s Respiratory Questionnaire (SGRQ) ≥25, as suggested by GOLD, following sensitivity and specificity analysis. In addition, areas under the curve (AUCs) of the CCQ, CAT, and mMRC scale were compared using two SGRQ cutoff points (≥25 and ≥20).
Materials and methods: Two data sets were used: study A, 238 patients from a pulmonary rehabilitation program; and study B, 101 patients from primary care. Receiver-operating characteristic (ROC) curves were used to assess the correspondence between the recommended cutoff points of the questionnaires.
Results: Sensitivity, specificity, and AUC scores for cutoff point SGRQ ≥25 were: study A, 0.99, 0.43, and 0.96 for CCQ ≥1, 0.92, 0.48, and 0.89 for CAT ≥10, and 0.68, 0.91, and 0.91 for mMRC ≥2; study B, 0.87, 0.77, and 0.9 for CCQ ≥1, 0.76, 0.73, and 0.82 for CAT ≥10, and 0.21, 1, and 0.81 for mMRC ≥2. Sensitivity, specificity, and AUC scores for cutoff point SGRQ ≥20 were: study A, 0.99, 0.73, and 0.99 for CCQ ≥1, 0.91, 0.73, and 0.94 for CAT ≥10, and 0.66, 0.95, and 0.94 for mMRC ≥2; study B, 0.8, 0.89, and 0.89 for CCQ ≥1, 0.69, 0.78, and 0.8 for CAT ≥10, and 0.18, 1, and 0.81 for mMRC ≥2.
Conclusion: Based on data from these two different samples, this study showed that the suggested cutoff point for the SGRQ (≥25) did not seem to correspond well with the established cutoff points of the CCQ or CAT scales, resulting in low specificity levels. The correspondence with the mMRC scale seemed satisfactory, though not optimal. The SGRQ threshold of ≥20 corresponded slightly better than SGRQ ≥25, recently suggested by GOLD 2015, with the established cutoff points for the CCQ, CAT, and mMRC scale.
KW - pulmonary disease
KW - chronic obstructive
KW - health status
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165427
VL - 11
ER -
TY - THES
A1 - Trüstedt, Jonas Elias
T1 - Long-wavelength radio observations of blazars with the Low-Frequency Array (LOFAR)
T1 - Beobachtungen von Blazaren bei langen Radio-Wellenlängen mit dem Low-Frequency Array (LOFAR)
N2 - Aktive Galaxienkerne (AGN) gehören zu den hellsten Objekten in unserem Universum. Diese Galaxien werden als aktiv bezeichnet, da ihre Zentralregion heller ist als alle Sterne in einer Galaxie zusammen beitragen könnten. Das Zentrum besteht aus einem supermassiven schwarzen Loch, das von einer Akkretionsscheibe und weiter außerhalb von einem Torus aus Staub umgeben ist. Diese AGN können über das ganze elektromagnetische Spektrum verteilt gefunden werden, von Radiowellen über Wellenlängen im optischen und Röntgenbereich bis hin zur $\gamma$-Strahlung. Allerdings sind nicht alle Objekte bei jeder Wellenlänge detektierbar. In dieser Arbeit werden überwiegend Blazare bei niedrigen Radiofrequenzen untersucht. Blazare gehören zu den radio-lauten AGN, welche üblicherweise stark kollimierte Jets senkrecht zur Akkretionsscheibe aussenden. Bei Blazaren sind diese Jets in die Richtung des Beobachters gerichtet und ihre Emissionen sind stark variabel. \\
AGN werden anhand ihres Erscheinungsbildes verschiedenen Untergruppen zugeordnet. Diese Untergruppen werden in einem vereinheitlichen AGN Modell zusammengeführt, welches besagt, dass diese Objekte sich nur in ihrer Luminosität und ihrem Winkel zur Sichtlinie unterscheiden. Blazare sind diejenigen Objekte, deren Jets in unsere Sichtrichtung zeigen, während die Objekte deren Jets eher senkrecht zur Sichtlinie orientiert sind als Radiogalaxien bezeichnet werden. Daraus folgt, dass Blazare die Gegenstücke zu Radiogalaxien mit einem anderen Winkel zur Sichtlinie sind. Diese Beziehung soll unter anderem in dieser Arbeit untersucht werden. \\
Nach ihrer Entdeckung in den 1940er Jahren wurden die aktiven Galaxien bei allen zugänglichen Wellenlängen untersucht. Durch die Entwicklung von Interferometern aus Radioteleskopen, welche eine erhöhte Auflösung bieten, konnten die Beobachtungen stark verbessert werden. In den letzten 20 Jahren wurden viele AGN regelmäßig beobachtet. Dies erfolgte unter anderem durch Programme wie dem MOJAVE Programm, welches 274 AGNs regelmäßig mithilfe der Technik der ``Very Long Baseline Interferometry" (VLBI) beobachtet. Durch diese Beobachtungen konnten Informationen zur Struktur und Entwicklung der AGN und Jets gesammelt werden. Allerdings sind die Prozesse zur Bildung von Jets und deren Kollimation noch nicht vollständig bekannt. Durch relativistische Effekte ist es schwierig die eigentlichen Größen der Jets anstelle der scheinbaren zu messen. Um die intrinsische Energie von Jets zu messen, sollen die ausgedehnten Emissionsregionen untersucht werden, in denen die Jets enden und mit dem Intergalaktischen Medium interagieren. Beobachtungen bei niedrigen Radiofrequenzen sind empfindlicher um solche ausgedehnte, diffuse Emissionsregionen zu detektieren. \\
Seit Dezember 2012 ist ein neues Radioteleskop für niedrige Frequenzen in Betrieb, dessen Stationen aus Dipolantennen besteht. Die meisten dieser Stationen sind in den Niederlanden verteilt (38 Stationen) und werden durch 12 internationale Stationen in Deutschland, Frankreich, Schweden, Polen und England ergänzt. Dieses Instrument trägt den Namen ``Low Frequency Array'' (LOFAR). LOFAR bietet die Möglichkeit bei Frequenzen von 30--250 MHz bei einer höheren Auflösung als bisherige Radioteleskope zu beobachten (Winkelauflösungen unter 1 arcsec für das gesamte Netzwerk aus Teleskopen). \\
Diese Arbeit behandelt die Ergebnisse von Blazaruntersuchungen mithilfe von LOFAR-Beobachtungen. Dafür wurden AGNs aus dem MOJAVE Programm verwendet um von den bisherigen Multiwellenlängen-Beobachtungen und Untersuchungen der Kinematik zu profitieren. Das ``Multifrequency Snapshot Sky Survey'' (MSSS) Projekt hat den gesamten Nordhimmel mit kurzen Beobachtungen abgerastert. Aus dem daraus resultierenden vorläufigen Katalog wurden die Flussdichten und Spektralindizes für MOJAVE-Blazare untersucht. In den kurzen Beobachtungen von MSSS sind nur die Stationen in den Niederlanden verwendet worden, wodurch Auflösung und Sensitivität begrenzt sind. Für die Erstellung des vorläufigen Kataloges wurde die Auflösung auf $\sim$120 arcsec beschränkt. Ein weiterer Vorteil der MOJAVE Objekte ist die regelmäßige Beobachtung der AGN mit dem ``Owens Vally Radio Observatory'' zur Erstellung von Lichtkurven bei 15 GHz. Dadurch ist es möglich nahezu zeitgleiche Flussdichtemessungen bei 15 GHz zu den entsprechenden MSSS-Beobachtungen zu bekommen. Da diese Beobachtungen zu ähnlichen Zeitpunkten durchgeführt wurden sind diese Flussdichten weniger von der Variabilität der Blazare beeinflusst. Die Spektralindizes berechnet aus den Flussdichten von MSSS und OVRO können verwendet werden um den Anteil an ausgedehnter Emission der AGNs abzuschätzen. \\
Im Vergleich der Flussdichten aus dem MSSS Katalog mit den Beobachtungen von OVRO fällt auf, dass die Flussdichten bei niedrigen Frequenzen tendenziell höher sind, was durch den höheren Anteil an ausgedehnter Struktur zu erwarten ist. Die Spektralindexverteilung zwischen MSSS und OVRO zeigt ihren höchsten Wert bei $\sim-0.2$. In der Verteilung existieren Objekte mit steilerem Spektralindex durch den höheren Anteil von ausgedehnter Emission in der Gesamtflussdichte, doch über die Hälfte der untersuchten Objekte besitzt flache Spektralindizes. Die flachen Spektralindizes bedeuten, dass die Emissionen dieser Objekte größtenteils von relativistischen Effekten beeinflusst sind, die schon aus Beobachtungen bei GHz-Frequenzen bekannt sind. \\
Durch neue Auswertung der MSSS Beobachtungsdaten konnten Bilder bei einer verbesserten Auflösung von $\sim$20--30 arcsec erstellt werden, wodurch bei einigen Blazaren ausgedehnte Struktur detektiert werden konnte. Diese höher aufgelösten Bilder sind allerdings nicht komplett kalibriert und können somit nur für strukturelle Informationen verwendet werden. Die Überarbeitung der Beobachtungsdaten konnte für 93 Objekte für ein Frequenzband durchgeführt werden. Für 45 der 93 Objekte konnten sogar alle vorhandenen Frequenzbänder überarbeitet werden und dadurch gemittelte Bilder erstellt werden. Diese Bilder werden in dieser Arbeit vorgestellt. Die resultierenden Bilder mit verbesserter Auflösung wurden verwendet um Objekte auszuwählen, die mit allen LOFAR-Stationen beobachtet und auf ausgedehnte Struktur untersucht werden können. \\
Im zweiten Teil der Arbeit werden die Ergebnisse von internationalen LOFAR Beobachtungen von vier Blazaren präsentiert. Da sich die Auswertung und Kalibration von internationalen LOFAR Beobachtungen noch in der Entwicklung befindet, wurde ein Schwerpunkt auf die Kalibration und deren Beschreibung gelegt. Die Kalibration kann zwar noch verbessert werden, aber die Bilder aus der angewandten Kalibration erreichen eine Auflösung von unter 1 arcsec. Die Struktur der untersuchten vier Blazare entspricht den Erwartungen für Radiogalaxien unter einem anderen Sichtwinkel. Durch die gemessenen Flussdichten der ausgedehnten Struktur aus den Helligkeitsverteilungen konnte die Luminosität der ausgedehnten Emissionen berechnet werden. Im Vergleich mit den Luminositäten, die von Radiogalaxien bekannt sind, entsprechen auch diese Werte den Erwartungen des vereinheitlichten AGN Modells. \\
Durch die in dieser Arbeit vorgestellte Kalibration können noch mehr Blazare mit LOFAR inklusive den internationalen Stationen beobachtet werden und somit Bilder der Struktur bei ähnlicher Auflösung erstellt werden. Durch eine erhöhte Anzahl von untersuchten Blazaren könnten anschließend auch statistisch signifikante Ergebnisse erzielt werden.\\
N2 - Active galactic nuclei (AGNs) are among the brightest sources in our universe. These galaxies are considered active because their central region is brighter than the luminosities of all stars in a galxies can provide. In their center is a supermassive black hole (SMBH) surrounded by an accretion disk and further out a dusty torus. AGN can be found with emission over the whole electromagnetic spectrum, starting at radio frequencies over optical and X-ray emission up to the $\gamma$-rays. Not all of these sources are detected in each frequency regime. In this work mainly blazars are examined at low radio frequencies. Blazars are a subclass of radio-loud AGN. These radio-loud sources usually exhibit highly collimated jets perpendicular to the accretion disk. For blazars these jets are pointed in the direction of the observer and their emission is highly variable. \\
AGN are classified in different subclasses based on their morphology. These different subclasses are combined in the AGN unification model, which explains the different morphologies by having sources only varying in their luminosities and their angle to the line of sight to the observer. Blazars are these targets, where the jet is pointing towards the observer, while the AGN observed edge on are called radio galaxies. This means that blazars should be the counterparts to radio galaxies seen from a different angle. Testing this is one of the goals in this work. \\
After the discovery of AGN in the 1940s these objects have been studied at all wavelengths. With the development of interferometry with radio telescopes the angular resolution for radio observations could be improved. In the last 20 years many AGN are regularly monitored. One of these monitoring programs is the MOJAVE program, monitoring 274 AGNs with using the Very Long Baseline Interferometry (VLBI) technique. The monitoring provides information on the evolution and structure of AGN and their jets. However, the mechanisms of the jet formation and their collimation are not fully understood. Due to relativistic effects it is difficult to obtain intrinsic instead of apparent parameters of these jets. One approach to get closer to the intrinsic jet power is by observing the regions, in which the jets end and interact with the intergalactic medium. Observations at lower radio frequencies are more sensitive for extended diffuse emission. \\
Since December 2012 a new radio telescope for low frequencies is observing. It is a telescope with stations consisting of dipole antennas. The major part of the array located in the Netherlands (38 stations) with 12 additional international stations in Germany, France, Sweden, Poland and the United Kingdom. This instrument is called the Low Frequency Array (LOFAR). LOFAR offers the possibility to observe at frequencies between 30--250 MHz in combination with angular resolution (below 1 arcsec for the full array), which was not available with previous telescopes. \\
In this work results of blazar studies with LOFAR observations are presented. To take advantage of a large database with multi-wavelength observations and kinematic studies the MOJAVE 1.5 Jy flux limited sample was chosen. Based on the preliminary results of the LOFAR Multifrequency Snapshot Sky Survey (MSSS) the flux densities and spectral indices of blazars of the MOJAVE sample are examined. 125 counterparts of MOJAVE blazars were found in the MSSS catalog. Since the MSSS observations only contain the stations in the Netherlands and observes in snapshots, the angular resolution and the sensitivity is limited. The first MSSS catalog was produced with an angular resolution of $\sim$120 arcsec and a sensitivity of $\sim$50--100 mJy. Another advantage of the MOJAVE sample is the monitoring of these sources with the Owens Valley Radio Observatory (OVRO) at 15 GHz to produce radio lightcurves. With these observations it is possible to get quasi-simultaneous flux densities at 15 GHz for the corresponding MSSS observations. By having quasi-simultaneous observations the variability of the blazars affects the flux densities less than with the use of archival data. The spectral indices obtained by the combination of MSSS and OVRO flux densities can be used to estimate the contribution of the diffuse extended emission for these AGNs. \\
Comparing the MSSS catalog with the OVRO data points, the flux densities have a tendency to be higher at low frequencies. This is expected due to the higher contribution of extended emission. The broadband spectral index distribution shows a peak at $\sim-0.2$. While some sources seem to have steeper spectral indices meaning that extended emission contributes a large fraction of the total flux density, more than the half of the sample shows flat spectral indices. The flat spectral indices show that the total flux densities of these sources are dominated by their relativistic beamed emission regions, which is the same for the observations at GHz frequencies. \\
To obtain more detailed images of these sources the MSSS measurement sets including sources of the sample were reprocessed to improve the angular resolution to $\sim$30 arcsec. The higher angular resolution reveals extended diffuse emission of several blazars. Since the reimaging results were not fully calibrated only the morphology at this resolution could be examined. However, with the short snapshot observations the images obtained with this strategy are affected from artifacts. The reimaging could be successfully performed for 93 sources in one frequency band. For 45 of these sources all availabe frequency bands could be reprocessed and used to created averaged images. These images are presented in this work. As a results of the reimaging process a pilot sample was defined to observe targets with diffuse extended emission using the whole LOFAR array including the international stations. \\
The second part of this work presents the results of a pilot sample consisting of four blazars observed with the LOFAR international array. Since the calibration of this kind of LOFAR observation is still in development, the main focus was the description of the used calibration strategy. The calibration strategies still has some limitation but resulted in images with angular resolutions of less than 1 arcsec. The morphology of all four blazars show features confirming the expectations of their counterpart radio galaxies. With the flux densities of the extended emission found in these brightness distributions the extended radio luminosities are calculated. Comparing these to the radio galaxy classifications also confirm the expectations from the unification model. \\
By extending the sample of observed blazars with LOFAR international in future the calibration strategy can be used to create similar high resolution images. A larger sample can be used to test the unification model with statistical significant results. \\
KW - Blazar
KW - Radioastronomie
KW - Blazars
KW - Active Galaxies
KW - Radio Interferometry
KW - Radio astronomy
KW - LOFAR
KW - Aktive Galaxie
KW - Radioteleskop
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-144406
ER -
TY - JOUR
A1 - Trudzinski, Franziska C.
A1 - Minko, Peter
A1 - Rapp, Daniel
A1 - Fähndrich, Sebastian
A1 - Haake, Hendrik
A1 - Haab, Myriam
A1 - Bohle, Rainer M.
A1 - Flaig, Monika
A1 - Kaestner, Franziska
A1 - Bals, Robert
A1 - Wilkens, Heinrike
A1 - Muellenbach, Ralf M.
A1 - Link, Andreas
A1 - Groesdonk, Heinrich V.
A1 - Lensch, Christian
A1 - Langer, Frank
A1 - Lepper, Philipp M.
T1 - Runtime and aPTT predict venous thrombosis and thromboembolism in patients on extracorporeal membrane oxygenation: a retrospective analysis
JF - Annals of Intensive Care
N2 - Background
Even though bleeding and thromboembolic events are major complications of extracorporeal membrane oxygenation (ECMO), data on the incidence of venous thrombosis (VT) and thromboembolism (VTE) under ECMO are scarce. This study analyzes the incidence and predictors of VTE in patients treated with ECMO due to respiratory failure.
Methods
Retrospective analysis of patients treated on ECMO in our center from 04/2010 to 11/2015. Patients with thromboembolic events prior to admission were excluded. Diagnosis was made by imaging in survivors and postmortem examination in deceased patients.
Results
Out of 102 screened cases, 42 survivors and 21 autopsy cases [mean age 46.0 ± 14.4 years; 37 (58.7 %) males] fulfilling the above-mentioned criteria were included. Thirty-four patients (54.0 %) underwent ECMO therapy due to ARDS, and 29 patients (46.0 %) with chronic organ failure were bridged to lung transplantation. Despite systemic anticoagulation at a mean PTT of 50.6 ± 12.8 s, [VT/VTE 47.0 ± 12.3 s and no VT/VTE 53.63 ± 12.51 s (p = 0.037)], VT and/or VTE was observed in 29 cases (46.1 %). The rate of V. cava thrombosis was 15/29 (51.7 %). Diagnosis of pulmonary embolism prevailed in deceased patients [5/21 (23.8 %) vs. 2/42 (4.8 %) (p = 0.036)]. In a multivariable analysis, only aPTT and time on ECMO predicted VT/VTE. There was no difference in the incidence of clinically diagnosed VT in ECMO survivors and autopsy findings.
Conclusions
Venous thrombosis and thromboembolism following ECMO therapy are frequent. Quality of anticoagulation and ECMO runtime predicted thromboembolic events.
"
KW - Pulmonary Embolism
KW - Inferior Vena Cava
KW - Venous Thrombosis
KW - Fresh Freeze Plasma
KW - Extracorporeal Membrane Oxygenation
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164455
VL - 6
ER -
TY - JOUR
A1 - Toussaint, André
A1 - Richter, Anne
A1 - Mantel, Frederick
A1 - Flickinger, John C.
A1 - Grills, Inga Siiner
A1 - Tyagi, Neelam
A1 - Sahgal, Arjun
A1 - Letourneau, Daniel
A1 - Sheehan, Jason P.
A1 - Schlesinger, David J.
A1 - Gerszten, Peter Carlos
A1 - Guckenberger, Matthias
T1 - Variability in spine radiosurgery treatment planning – results of an international multi-institutional study
JF - Radiation Oncology
N2 - Background
The aim of this study was to quantify the variability in spinal radiosurgery (SRS) planning practices between five international institutions, all member of the Elekta Spine Radiosurgery Research Consortium.
Methods
Four institutions provided one representative patient case each consisting of the medical history, CT and MR imaging. A step-wise planning approach was used where, after each planning step a consensus was generated that formed the basis for the next planning step. This allowed independent analysis of all planning steps of CT-MR image registration, GTV definition, CTV definition, PTV definition and SRS treatment planning. In addition, each institution generated one additional SRS plan for each case based on intra-institutional image registration and contouring, independent of consensus results.
Results
Averaged over the four cases, image registration variability ranged between translational 1.1 mm and 2.4 mm and rotational 1.1° and 2.0° in all three directions. GTV delineation variability was 1.5 mm in axial and 1.6 mm in longitudinal direction averaged for the four cases. CTV delineation variability was 0.8 mm in axial and 1.2 mm in longitudinal direction. CTV-to-PTV margins ranged between 0 mm and 2 mm according to institutional protocol. Delineation variability was 1 mm in axial directions for the spinal cord. Average PTV coverage for a single fraction18 Gy prescription was 87 ± 5 %; Dmin to the PTV was 7.5 ± 1.8 Gy averaged over all cases and institutions. Average Dmax to the PRV_SC (spinal cord + 1 mm) was 10.5 ± 1.6 Gy and the average Paddick conformity index was 0.69 ± 0.06.
Conclusions
Results of this study reflect the variability in current practice of spine radiosurgery in large and highly experienced academic centers. Despite close methodical agreement in the daily workflow, clinically significant variability in all steps of the treatment planning process was demonstrated. This may translate into differences in patient clinical outcome and highlights the need for consensus and established delineation and planning criteria.
KW - planning variability
KW - spine radiosurgery
KW - vertebral metastases
KW - delineation
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146687
VL - 11
IS - 57
ER -
TY - JOUR
A1 - Tinajero-Trejo, Mariana
A1 - Rana, Namrata
A1 - Nagel, Christoph
A1 - Jesse, Helen E.
A1 - Smith, Thomas W.
A1 - Wareham, Lauren K.
A1 - Hippler, Michael
A1 - Schatzschneider, Ulrich
A1 - Poole, Robert K.
T1 - Antimicrobial Activity of the Manganese Photoactivated Carbon Monoxide-Releasing Molecule [Mn(CO)\(_3\)(tpa-kappa\(^3\)N)]\(^+\) Against a Pathogenic Escherichia coli that Causes Urinary Infections
JF - Antioxidants & Redox Signaling
N2 - Aims: We set out to investigate the antibacterial activity of a new Mn-based photoactivated carbon monoxide-releasing molecule (PhotoCORM, [Mn(CO)\(_3\)(tpa-kappa\(^3\)N)]\(^+\)) against an antibiotic-resistant uropathogenic strain (EC958) of Escherichia coli. Results: Activated PhotoCORM inhibits growth and decreases viability of E. coli EC958, but non-illuminated carbon monoxide-releasing molecule (CORM) is without effect. NADH-supported respiration rates are significantly decreased by activated PhotoCORM, mimicking the effect of dissolved CO gas. CO from the PhotoCORM binds to intracellular targets, namely respiratory oxidases in strain EC958 and a bacterial globin heterologously expressed in strain K-12. However, unlike previously characterized CORMs, the PhotoCORM is not significantly accumulated in cells, as deduced from the cellular manganese content. Activated PhotoCORM reacts avidly with hydrogen peroxide producing hydroxyl radicals; the observed peroxide-enhanced toxicity of the PhotoCORM is ameliorated by thiourea. The PhotoCORM also potentiates the effect of the antibiotic, doxycycline. Innovation: The present work investigates for the first time the antimicrobial activity of a light-activated PhotoCORM against an antibiotic-resistant pathogen. A comprehensive study of the effects of the PhotoCORM and its derivative molecules upon illumination is performed and mechanisms of toxicity of the activated PhotoCORM are investigated. Conclusion: The PhotoCORM allows a site-specific and time-controlled release of CO in bacterial cultures and has the potential to provide much needed information on the generality of CORM activities in biology. Understanding the mechanism(s) of activated PhotoCORM toxicity will be key in exploring the potential of this and similar compounds as antimicrobial agents, perhaps in combinatorial therapies with other agents.
KW - intracellular hydrogen-peroxide
KW - campylobacter-jejuni
KW - oxygen-metabolism
KW - deficient mutant
KW - oxidative stress
KW - aqueous-solution
KW - metal caponyls
KW - RU(CO)(3)CL(GLYCINATE)
KW - bacteria
KW - enzyme
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-188910
VL - 24
IS - 14
ER -
TY - JOUR
A1 - Tiede, Jennifer
A1 - Grafe, Silke
T1 - Media Pedagogy in German and US Teacher Education
JF - Communicar
N2 - Varios estudios de investigación y de práctica llegan a la conclusión de que la pedagogía de los medios debe integrarse en la formación de profesores para que estos futuros docentes puedan utilizar los medios de comunicación en sus clases con eficacia y éxito. Sin embargo, estos resultados no se reflejan en los programas universitarios vigentes, de manera que en algunas instituciones los profesores en formación pueden llegar al término de sus estudios sin haber abordado cuestiones de educación en medios. Para comprender, evaluar y más adelante mejorar la situación actual de la formación del profesorado en el ámbito de la pedagogía de los medios se necesitan extensas investigaciones. Teniendo en cuenta esta situación, el siguiente artículo presenta un resumen del «statu quo» de las competencias en pedagogía de los medios de los futuros profesores, centrándose en los ejemplos de Alemania y EEUU. Para crear una base presentamos diferentes modelos de competencias pedagógicas mediáticas de ambos países e intentaremos responder a la pregunta si estas competencias son promovidas por los programas de formación del profesorado. Después, se describirán el método y resultados seleccionados de un estudio que midió las competencias en pedagogía de los medios de estudiantes de ambos países, estudio basado en un modelo generalizador de competencias pedagógicas mediáticas que conectan la investigación alemana e internacional en este campo. La perspectiva internacional comparada ayuda a extender perspectivas y comprender diferencias y similitudes. Los datos de este estudio sirven para identificar diferentes formas de integrar la pedagogía de los medios de comunicación en la formación del profesorado. Además, se pueden sacar conclusiones sobre las consecuencias que implican estos procesos para profesores en formación y sus competencias mediáticas.
N2 - Various research works and practitioners conclude that media pedagogy should be integrated in teacher education in order to enable future teachers to use media for their lessons effectively and successfully. However, this realization is not necessarily reflected in actual university curricula, as preservice teachers at some places can still finish their studies without ever dealing with media pedagogical issues. To understand, assess and eventually improve the status of media pedagogical teacher education, comprehensive research is required. Against this background, the following article seeks to present a theory-based and empirical overview of the status quo of preservice teachers’ pedagogical media competencies focusing Germany and the USA exemplarily. To form a basis, different models of pedagogical media competencies from both countries will be introduced and the extent to which these competencies have become part of teacher education programs and related studies will be summarised. Afterwards, method and selected results of a study will be described where the skills in question were measured with students from both countries, based on a comprehensive model of pedagogical media competencies that connects German and international research in this field. The international comparative perspective will help broaden the viewpoint and understand differences, but also similarities. These data serve to identify different ways of integrating media pedagogy into teacher training and draw conclusions on the consequences these processes entail for preservice teachers and their pedagogical media competencies.
T2 - Pedagogía mediática en la formación de profesores de Alemania y EEUU
KW - enseñanzapor por competencias
KW - currículum
KW - análisis transnacional
KW - investigación de currículo universitario
KW - currículo de la educación en medios
KW - alfabetización mediática
KW - educación en medios
KW - pedagogía
KW - formación de profesorado
KW - investigación
KW - media literacy
KW - media education
KW - pedagogy
KW - preservice teacher education
KW - competency based teaching
KW - curricula
KW - research
KW - crossnational analysis
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-162600
VL - XXIV
IS - 49
ER -
TY - JOUR
A1 - Thormann, Birthe
A1 - Ahrens, Dirk
A1 - Armijos, Diego Marín
A1 - Peters, Marcell K.
A1 - Wagner, Thomas
A1 - Wägele, Johann W.
T1 - Exploring the Leaf Beetle Fauna (Coleoptera: Chrysomelidae) of an Ecuadorian Mountain Forest Using DNA Barcoding
JF - PLoS ONE
N2 - Background
Tropical mountain forests are hotspots of biodiversity hosting a huge but little known diversity of insects that is endangered by habitat destruction and climate change. Therefore, rapid assessment approaches of insect diversity are urgently needed to complement slower traditional taxonomic approaches. We empirically compare different DNA-based species delimitation approaches for a rapid biodiversity assessment of hyperdiverse leaf beetle assemblages along an elevational gradient in southern Ecuador and explore their effect on species richness estimates.
Methodology/Principal Findings
Based on a COI barcode data set of 674 leaf beetle specimens (Coleoptera: Chrysomelidae) of 266 morphospecies from three sample sites in the Podocarpus National Park, we employed statistical parsimony analysis, distance-based clustering, GMYC- and PTP-modelling to delimit species-like units and compared them to morphology-based (parataxonomic) species identifications. The four different approaches for DNA-based species delimitation revealed highly similar numbers of molecular operational taxonomic units (MOTUs) (n = 284–289). Estimated total species richness was considerably higher than the sampled amount, 414 for morphospecies (Chao2) and 469–481 for the different MOTU types. Assemblages at different elevational levels (1000 vs. 2000 m) had similar species numbers but a very distinct species composition for all delimitation methods. Most species were found only at one elevation while this turnover pattern was even more pronounced for DNA-based delimitation.
Conclusions/Significance
Given the high congruence of DNA-based delimitation results, probably due to the sampling structure, our study suggests that when applied to species communities on a regionally limited level with high amount of rare species (i.e. ~50% singletons), the choice of species delimitation method can be of minor relevance for assessing species numbers and turnover in tropical insect communities. Therefore, DNA-based species delimitation is confirmed as a valuable tool for evaluating biodiversity of hyperdiverse insect communities, especially when exact taxonomic identifications are missing.
KW - leaf beetle
KW - Coleoptera: Chrysomelidae
KW - Podocarpus National Park
KW - DNA-based species delimitation
KW - biodiversity
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167253
VL - 11
IS - 2
ER -
TY - JOUR
A1 - Thomas, Anna C.
A1 - Zeng, Zhiqiang
A1 - Rivière, Jean-Baptiste
A1 - O'Shaughnessy, Ryan
A1 - Al-Olabi, Lara
A1 - St.-Onge, Judith
A1 - Atherton, David J.
A1 - Aubert, Hélène
A1 - Bagazgoitia, Lorea
A1 - Barbarot, Sébastien
A1 - Bourrat, Emmanuelle
A1 - Chiaverini, Christine
A1 - Chong, W. Kling
A1 - Duffourd, Yannis
A1 - Glover, Mary
A1 - Groesser, Leopold
A1 - Hadj-Rabia, Smail
A1 - Hamm, Henning
A1 - Happle, Rudolf
A1 - Mushtaq, Imran
A1 - Lacour, Jean-Philippe
A1 - Waelchli, Regula
A1 - Wobser, Marion
A1 - Vabres, Pierre
A1 - Patton, E. Elizabeth
A1 - Kinsler, Veronica A.
T1 - Mosaic activating mutations in GNA11 and GNAQ are associated with phakomatosis pigmentovascularis and extensive dermal melanocytosis
JF - Journal of Investigative Dermatology
N2 - Common birthmarks can be an indicator of underlying genetic disease but are often overlooked. Mongolian blue spots (dermal melanocytosis) are usually localized and transient, but they can be extensive, permanent, and associated with extracutaneous abnormalities. Co-occurrence with vascular birthmarks defines a subtype of phakomatosis pigmentovascularis, a group of syndromes associated with neurovascular, ophthalmological, overgrowth, and malignant complications. Here, we discover that extensive dermal melanocytosis and phakomatosis pigmentovascularis are associated with activating mutations in GNA11 and GNAQ, genes that encode Ga subunits of heterotrimeric G proteins. The mutations were detected at very low levels in affected tissues but were undetectable in the blood, indicating that these conditions are postzygotic mosaic disorders. In vitro expression of mutant GNA11\(^R183C\) and GNA11\(^Q209L\) in human cell lines demonstrated activation of the downstream p38 MAPK signaling pathway and the p38, JNK, and ERK pathways, respectively. Transgenic mosaic zebrafish models expressing mutant GNA11\(^R183C\) under promoter mitfa developed extensive dermal melanocytosis recapitulating the human phenotype. Phakomatosis pigmentovascularis and extensive dermal melanocytosis are therefore diagnoses in the group of mosaic heterotrimeric G-protein disorders, joining McCune-Albright and Sturge-Weber syndromes. These findings will allow accurate clinical and molecular diagnosis of this subset of common birthmarks, thereby identifying infants at risk for serious complications, and provide novel therapeutic opportunities.
KW - uveal melanoma
KW - G Protein
KW - dermal melanocytosis
KW - Sturge-Weber syndrom
KW - cesioflammea
KW - germline
KW - phakomatosis pigmentovascularis
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189689
VL - 136
IS - 4
ER -
TY - JOUR
A1 - Telorac, Jonas
A1 - Prykhozhij, Sergey V.
A1 - Schöne, Stefanie
A1 - Meierhofer, David
A1 - Sauer, Sascha
A1 - Thomas-Chollier, Morgane
A1 - Meijsing, Sebastiaan H.
T1 - Identification and characterization of DNA sequences that prevent glucocorticoid receptor binding to nearby response elements
JF - Nucleic Acids Research
N2 - Out of the myriad of potential DNA binding sites of the glucocorticoid receptor (GR) found in the human genome, only a cell-type specific minority is actually bound, indicating that the presence of a recognition sequence alone is insufficient to specify where GR binds. Cooperative interactions with other transcription factors (TFs) are known to contribute to binding specificity. Here, we reasoned that sequence signals preventing GR recruitment to certain loci provide an alternative means to confer specificity. Motif analyses uncovered candidate Negative Regulatory Sequences (NRSs) that interfere with genomic GR binding. Subsequent functional analyses demonstrated that NRSs indeed prevent GR binding to nearby response elements. We show that NRS activity is conserved across species, found in most tissues and that they also interfere with the genomic binding of other TFs. Interestingly, the effects of NRSs appear not to be a simple consequence of changes in chromatin accessibility. Instead, we find that NRSs interact with proteins found at sub-nuclear structures called paraspeckles and that these proteins might mediate the repressive effects of NRSs. Together, our studies suggest that the joint influence of positive and negative sequence signals partition the genome into regions where GR can bind and those where it cannot.
KW - DNA sequencing
KW - glucocorticoid receptor
KW - DNA binding
KW - transcription factors
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166330
VL - 44
IS - 13
ER -
TY - JOUR
A1 - Teichmann, Christoph
T1 - Corporate Restructuring under the EMCA
JF - European Company and Financial Law Review
N2 - No abstract available.
KW - corporate restructuring
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-194488
SN - 1613-2556
SN - 1613-2548
N1 - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.
VL - 13
IS - 2
SP - 277
EP - 300
ER -
TY - JOUR
A1 - Tegtmeyer, Nicole
A1 - Moodley, Yoshan
A1 - Yamaoka, Yoshio
A1 - Pernitzsch, Sandy Ramona
A1 - Schmidt, Vanessa
A1 - Traverso, Francisco Rivas
A1 - Schmidt, Thomas P.
A1 - Rad, Roland
A1 - Yeoh, Khay Guan
A1 - Bow, Ho
A1 - Torres, Javier
A1 - Gerhard, Markus
A1 - Schneider, Gisbert
A1 - Wessler, Silja
A1 - Backert, Steffen
T1 - Characterisation of worldwide Helicobacter pylori strains reveals genetic conservation and essentiality of serine protease HtrA
JF - Molecular Microbiology
N2 - HtrA proteases and chaperones exhibit important roles in periplasmic protein quality control and stress responses. The genetic inactivation of htrA has been described for many bacterial pathogens. However, in some cases such as the gastric pathogen Helicobacter pylori, HtrA is secreted where it cleaves the tumour-suppressor E-cadherin interfering with gastric disease development, but the generation of htrA mutants is still lacking. Here, we show that the htrA gene locus is highly conserved in worldwide strains. HtrA presence was confirmed in 992 H.pylori isolates in gastric biopsy material from infected patients. Differential RNA-sequencing (dRNA-seq) indicated that htrA is encoded in an operon with two subsequent genes, HP1020 and HP1021. Genetic mutagenesis and complementation studies revealed that HP1020 and HP1021, but not htrA, can be mutated. In addition, we demonstrate that suppression of HtrA proteolytic activity with a newly developed inhibitor is sufficient to effectively kill H.pylori, but not other bacteria. We show that Helicobacter htrA is an essential bifunctional gene with crucial intracellular and extracellular functions. Thus, we describe here the first microbe in which htrA is an indispensable gene, a situation unique in the bacterial kingdom. HtrA can therefore be considered a promising new target for anti-bacterial therapy.
KW - Helicobacter pylori
KW - cag pathogenicity island
KW - Differential RNA-sequencing
KW - epithelial cells
KW - campylobacter jejuni infection
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-190774
VL - 99
IS - 5
ER -
TY - JOUR
A1 - Taha, Muhamed-Kheir
A1 - Claus, Heike
A1 - Lappann, Martin
A1 - Veyrier, Frédéric J.
A1 - Otto, Andreas
A1 - Becher, Dörte
A1 - Deghmane, Ala-Eddine
A1 - Frosch, Matthias
A1 - Hellenbrand, Wiebke
A1 - Hong, Eva
A1 - du Châtelet, Isabelle Parent
A1 - Prior, Karola
A1 - Harmsen, Dag
A1 - Vogel, Ulrich
T1 - Evolutionary Events Associated with an Outbreak of Meningococcal Disease in Men Who Have Sex with Men
JF - PLoS ONE
N2 - Meningococci spread via respiratory droplets, whereas the closely related gonococci are transmitted sexually. Several outbreaks of invasive meningococcal disease have been reported in Europe and the United States among men who have sex with men (MSM). We recently identified an outbreak of serogroup C meningococcal disease among MSM in Germany and France. In this study, genomic and proteomic techniques were used to analyze the outbreak isolates. In addition, genetically identical urethritis isolates were recovered from France and Germany and included in the analysis. Genome sequencing revealed that the isolates from the outbreak among MSM and from urethritis cases belonged to a clade within clonal complex 11. Proteome analysis showed they expressed nitrite reductase, enabling anaerobic growth as previously described for gonococci. Invasive isolates from MSM, but not urethritis isolates, further expressed functional human factor H binding protein associated with enhanced survival in a newly developed transgenic mouse model expressing human factor H, a complement regulatory protein. In conclusion, our data suggest that urethritis and outbreak isolates followed a joint adaptation route including adaption to the urogenital tract.
KW - nitrites
KW - genome sequencing
KW - men who have sex with men
KW - meningococcal disease
KW - Neisseria meningitidis
KW - Neisseria gonorrhoeae
KW - mammalian genomics
KW - mouse models
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-179870
VL - 11
IS - 5
ER -
TY - JOUR
A1 - Szczerba, Wojciech
A1 - Zukrowski, Jan
A1 - Przybylski, Marek
A1 - Sikora, Marcin
A1 - Safonova, Olga
A1 - Shmeliov, Aleksey
A1 - Nicolosi, Valeria
A1 - Schneider, Michael
A1 - Granath, Tim
A1 - Oppmann, Maximilian
A1 - Straßer, Marion
A1 - Mandel, Karl
T1 - Pushing up the magnetisation values for iron oxide nanoparticles via zinc doping: X-ray studies on the particle's sub-nano structure of different synthesis routes
JF - Physical Chemistry Chemical Physics
N2 - The maximum magnetisation (saturation magnetisation) obtainable for iron oxide nanoparticles can be increased by doping the nanocrystals with non-magnetic elements such as zinc. Herein, we closely study how only slightly different synthesis approaches towards such doped nanoparticles strongly influence the resulting sub-nano/atomic structure. We compare two co-precipitation approaches, where we only vary the base (NaOH versus NH\(_3\)), and a thermal decomposition route. These methods are the most commonly applied ones for synthesising doped iron oxide nanoparticles. The measurable magnetisation change upon zinc doping is about the same for all systems. However, the sub-nano structure, which we studied with Mossbauer and X-ray absorption near edge spectroscopy, differs tremendously. We found evidence that a much more complex picture has to be drawn regarding what happens upon Zn doping compared to what textbooks tell us about the mechanism. Our work demonstrates that it is crucial to study the obtained structures very precisely when "playing'' with the atomic order in iron oxide nanocrystals.
KW - Ferrite
KW - FE
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187390
VL - 18
IS - 36
ER -
TY - JOUR
A1 - Suliman, Salwa
A1 - Sun, Yang
A1 - Pedersen, Torbjorn O.
A1 - Xue, Ying
A1 - Nickel, Joachim
A1 - Waag, Thilo
A1 - Finne-Wistrand, Anna
A1 - Steinmüller-Nethl, Doris
A1 - Krueger, Anke
A1 - Costea, Daniela E.
A1 - Mustafa, Kamal
T1 - In vivo host response and degradation of copolymer scaffolds functionalized with nanodiamonds and bone morphogenetic protein 2
JF - Advanced Healthcare Materials
N2 - The aim is to evaluate the effect of modifying poly[(L-lactide)-co-(epsilon-caprolactone)] scaffolds (PLCL) with nanodiamonds (nDP) or with nDP+physisorbed BMP-2 (nDP+BMP-2) on in vivo host tissue response and degradation. The scaffolds are implanted subcutaneously in Balb/c mice and retrieved after 1, 8, and 27 weeks. Molecular weight analysis shows that modified scaffolds degrade faster than the unmodified. Gene analysis at week 1 shows highest expression of proinflammatory markers around nDP scaffolds; although the presence of inflammatory cells and foreign body giant cells is more prominent around the PLCL. Tissue regeneration markers are highly expressed in the nDP+BMP-2 scaffolds at week 8. A fibrous capsule is detectable by week 8, thinnest around nDP scaffolds and at week 27 thickest around PLCL scaffolds. mRNA levels of ALP, COL1 alpha 2, and ANGPT1 are signifi cantly upregulating in the nDP+BMP-2 scaffolds at week 1 with ectopic bone seen at week 8. Even when almost 90% of the scaffold is degraded at week 27, nDP are observable at implantation areas without adverse effects. In conclusion, modifying PLCL scaffolds with nDP does not aggravate the host response and physisorbed BMP-2 delivery attenuates infl ammation while lowering the dose of BMP-2 to a relatively safe and economical level.
KW - inflammatory response
KW - biocompatibility
KW - BMP-2 delivery
KW - inflammation
KW - tissue engineering
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189764
VL - 5
IS - 6
ER -
TY - JOUR
A1 - Suliman, Salwa
A1 - Mustafa, Kamal
A1 - Krueger, Anke
A1 - Steinmüller-Nethl, Doris
A1 - Finne-Wistrand, Anna
A1 - Osdal, Tereza
A1 - Hamza, Amani O.
A1 - Sun, Yang
A1 - Parajuli, Himalaya
A1 - Waag, Thilo
A1 - Nickel, Joachim
A1 - Johannessen, Anne Christine
A1 - McCormack, Emmet
A1 - Costea, Daniela Elena
T1 - Nanodiamond modified copolymer scaffolds affects tumour progression of early neoplastic oral keratinocytes
JF - Biomaterials
N2 - This study aimed to evaluate the tumorigenic potential of functionalising poly(LLA-co-CL) scaffolds. The copolymer scaffolds were functionalised with nanodiamonds (nDP) or with nDP and physisorbed BMP-2 (nDP-PHY) to enhance osteoinductivity. Culturing early neoplastic dysplastic keratinocytes (DOK\(^{Luc}\)) on nDP modified scaffolds reduced significantly their subsequent sphere formation ability and decreased significantly the cells' proliferation in the supra-basal layers of in vitro 3D oral neoplastic mucosa (3D-OT) when compared to DOK\(^{Luc}\) previously cultured on nDP-PHY scaffolds. Using an in vivo non-invasive environmentally-induced oral carcinogenesis model, nDP scaffolds were observed to reduce bioluminescence intensity of tumours formed by DOK\(^{Luc}\) + carcinoma associated fibroblasts (CAF). nDP modification was also found to promote differentiation of DOK\(^{Luc}\) both in vitro in 3D-OT and in vivo in xenografts formed by DOKLuc alone. The nDP-PHY scaffold had the highest number of invasive tumours formed by DOK\(^{Luc}\) + CAF outside the scaffold area compared to the nDP and control scaffolds. In conclusion, in vitro and in vivo results presented here demonstrate that nDP modified copolymer scaffolds are able to decrease the tumorigenic potential of DOK\(^{Luc}\), while confirming concerns for the therapeutic use of BMP-2 for reconstruction of bone defects in oral cancer patients due to its tumour promoting capabilities.
KW - Bone morphogenetic protein-2
KW - Sinus floor augmentation
KW - Marrow stromal cells
KW - Growth; BMP-2
KW - Tumorigenicity
KW - Biodegradable polymer scaffolds
KW - Mandibular continuity defects
KW - Squamous-cell carcinoma
KW - In-vitro
KW - Mesenchymal transition
KW - BMP-2
KW - Bone tissue engineering
KW - Biocompatibility
KW - Microenvironment
KW - Oral squamous cell carcinoma
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-188287
VL - 95
ER -
TY - JOUR
A1 - Subramanian, Hariharan
A1 - Döring, Frank
A1 - Kollert, Sina
A1 - Rukoyatkina, Natalia
A1 - Sturm, Julia
A1 - Gambaryan, Stepan
A1 - Stellzig-Eisenhauer, Angelika
A1 - Meyer-Marcotty, Philipp
A1 - Eigenthaler, Martin
A1 - Wischmeyer, Erhard
T1 - PTH1R Mutants Found in Patients with Primary Failure of Tooth Eruption Disrupt G-Protein Signaling
JF - PLoS One
N2 - Aim
Primary failure of tooth eruption (PFE) is causally linked to heterozygous mutations of the parathyroid hormone receptor (PTH1R) gene. The mutants described so far lead to exchange of amino acids or truncation of the protein that may result in structural changes of the expressed PTH1R. However, functional effects of these mutations have not been investigated yet.
Materials and Methods
In HEK293 cells, PTH1R wild type was co-transfected with selected PTH1R mutants identified in patients with PFE. The effects on activation of PTH-regulated intracellular signaling pathways were analyzed by ELISA and Western immunoblotting. Differential effects of wild type and mutated PTH1R on TRESK ion channel regulation were analyzed by electrophysiological recordings in Xenopus laevis oocytes.
Results
In HEK293 cells, activation of PTH1R wild type increases cAMP and in response activates cAMP-stimulated protein kinase as detected by phosphorylation of the vasodilator stimulated phosphoprotein (VASP). In contrast, the PTH1R mutants are functionally inactive and mutant PTH1R/Gly452Glu has a dominant negative effect on the signaling of PTH1R wild type. Confocal imaging revealed that wild type PTH1R is expressed on the cell surface, whereas PTH1R/Gly452Glu mutant is mostly retained inside the cell. Furthermore, in contrast to wild type PTH1R which substantially augmented K+ currents of TRESK channels, coupling of mutated PTH1R to TRESK channels was completely abolished.
Conclusions
PTH1R mutations affect intracellular PTH-regulated signaling in vitro. In patients with primary failure of tooth eruption defective signaling of PTH1R mutations is suggested to occur in dento-alveolar cells and thus may lead to impaired tooth movement.
KW - phosphorylation
KW - xenopus oocytes
KW - calcium signaling
KW - intracellular receptors
KW - mutation
KW - teeth
KW - tooth eruption
KW - transfection
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147967
VL - 11
IS - 11
ER -
TY - JOUR
A1 - Stölzel, F.
A1 - Mohr, B.
A1 - Kramer, M.
A1 - Oelschlägel, U.
A1 - Bochtler, T.
A1 - Berdel, W. E.
A1 - Kaufmann, M.
A1 - Baldus, C. D.
A1 - Schäfer-Eckart, K.
A1 - Stuhlmann, R.
A1 - Einsele, H.
A1 - Krause, S. W.
A1 - Serve, H.
A1 - Hänel, M.
A1 - Herbst, R.
A1 - Neubauer, A.
A1 - Sohlbach, K.
A1 - Mayer, J.
A1 - Middeke, J. M.
A1 - Platzbecker, U.
A1 - Schaich, M.
A1 - Krämer, A.
A1 - Röllig, C.
A1 - Schetelig, J.
A1 - Bornhäuser, M.
A1 - Ehninger, G.
T1 - Karyotype complexity and prognosis in acute myeloid leukemia
JF - Blood Cancer Journal
N2 - A complex aberrant karyotype consisting of multiple unrelated cytogenetic abnormalities is associated with poor prognosis in patients with acute myeloid leukemia (AML). The European Leukemia Net classification and the UK Medical Research Council recommendation provide prognostic categories that differ in the definition of unbalanced aberrations as well as the number of single aberrations. The aim of this study on 3526 AML patients was to redefine and validate a cutoff for karyotype complexity in AML with regard to adverse prognosis. Our study demonstrated that (1) patients with a pure hyperdiploid karyotype have an adverse risk irrespective of the number of chromosomal gains, (2) patients with translocation t(9;11)(p21∼22;q23) have an intermediate risk independent of the number of additional aberrations, (3) patients with 4 abnormalities have an adverse risk per se and (4) patients with three aberrations in the absence of abnormalities of strong influence (hyperdiploid karyotype, t(9;11)(p21∼22;q23), CBF-AML, unique adverse-risk aberrations) have borderline intermediate/adverse risk with a reduced overall survival compared with patients with a normal karyotype.
KW - Cancer genetics
KW - Genetics research
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164530
VL - 6
ER -
TY - THES
A1 - Stuckensen, Kai
T1 - Fabrication of hierarchical cell carrier matrices for tissue regeneration by directional solidification
T1 - Herstellung hierarchischer Zellträger-Matrices zur Geweberegeneration mittels gerichteter Erstarrung
N2 - The key hypothesis of this work represented the question, if mimicking the zonal composition and structural porosity of musculoskeletal tissues influences invading cells positively and leads to advantageous results for tissue engineering. Conventional approaches in tissue engineering are limited in producing monolithic “scaffolds” that provide locally variating biological key signals and pore architectures, imitating the alignment of collagenous fibres in bone and cartilage tissues, respectively. In order to fill this gap in available tissue engineering strategies, a new fabrication technique was evolved for the production of scaffolds to validate the hypothesis.
Therefore, a new solidification based platform procedure was developed. This process comprises the directional solidification of multiple flowable precursors that are “cryostructured” to prepare a controlled anisotropic pore structure. Porous scaffolds are attained through ice crystal removal by lyophilisation. Optionally, electrostatic spinning of polymers may be applied to provide an external mesh on top or around the scaffolds. A consolidation step generates monolithic matrices from multi zonal structures. To serve as matrix for tissue engineering approaches or direct implantation as medical device, the scaffold is sterilized.
An Adjustable Cryostructuring Device (ACD) was successively developed; individual parts were conceptualized by computer aided design (CAD) and assembled. During optimisation, a significant performance improvement of the ACDs accessible external temperature gradient was achieved, from (1.3 ± 0.1) K/mm to (9.0 ± 0.1) K/mm. Additionally, four different configurations of the device were made available that enabled the directional solidification of collagenous precursors in a highly controlled manner with various sample sizes and shapes.
By using alginate as a model substance the process was systematically evaluated. Cryostructuring diagraphs were analysed yielding solidification parameters, which were associated to pore sizes and alignments that were determined by image processing. Thereby, a precise control over pore size and alignment through electrical regulation of the ACD could be demonstrated.
To obtain tissue mimetic scaffolds for the musculoskeletal system, collagens and calcium phosphates had to be prepared to serve as raw materials. Extraction and purification protocols were established to generate collagen I and collagen II, while the calcium phosphates brushite and hydroxyapatite were produced by precipitation reactions.
Besides the successive augmentation of the ACD also an optimization of the processing steps was crucial. Firstly, the concentrations and the individual behaviour of respective precursor components had to be screened. Together with the insights gained by videographic examination of solidifying collagen solutions, essential knowledge was gained that facilitated the production of more complex scaffolds. Phenomena of ice crystal growth during cryostructuring were discussed. By evolutionary steps, a cryostructuring of multi-layered precursors with consecutive anisotropic pores could be achieved and successfully transferred from alginate to collagenous precursors. Finally, very smooth interfaces that were hardly detectable by scanning electron microscopy (SEM) could be attained. For the used collagenous systems, a dependency relation between adjustable processing parameters and different resulting solidification morphologies was created.
Dehydrothermal-, diisocyanate-, and carbodiimide- based cross linking methods were evaluated, whereby the “zero length” cross linking by carbodiimide was found to be most suitable. Afterwards, a formulation for the cross linking solution was elaborated, which generated favourable outcomes by application inside a reduced pressure apparatus. As a consequence, a pore collapse during wet chemical cross linking could be avoided.
Complex monolithic scaffolds featuring continuous pores were fabricated that mimicked structure and respective composition of different areas of native tissues by the presence of biochemical key stimulants. At first, three types of bone scaffolds were produced from collagen I and hydroxyapatite with appropriate sizes to fit critical sized defects in rat femurs. They either featured an isotropic or anisotropic porosity and partly also contained glycosaminoglycans (GAGs). Furthermore, meniscus scaffolds were prepared by processing two precursors with biomimetic contents of collagen I, collagen II and GAGs. Here, the pore structures were created under boundary conditions, which allowed an ice crystal growth that was nearly orthogonal to the external temperature gradient. Thereby, the preferential alignment of collagen fibres in the natural meniscus tissue could be mimicked. Those scaffolds owned appropriate sizes for cell culture in well plates or even an authentic meniscus shape and size. Finally, osteochondral scaffolds, sized to either fit well plates or perfusion reactors for cell culture, were fabricated to mimic the composition of subchondral bone and different cartilage zones. Collagen I and the resorbable calcium phosphate brushite were used for the subchondral zone, whereas the cartilage zones were composed out of collagen I, collagen II and tissue mimetic contents of GAGs. The pore structure corresponded to the one that is dominating the volume of natural osteochondral tissue.
Energy dispersive X-ray spectroscopy (EDX) and SEM were used to analyse the composition and pore structure of the individual scaffold zones, respectively. The cross section pore diameters were determined to (65 ± 25) µm, (88 ± 35) µm and(93 ± 42) µm for the anisotropic, the isotropic and GAG containing isotropic bone scaffolds. Furthermore, the meniscus scaffolds showed pore diameters of (93 ± 21) µm in the inner meniscus zone and (248 ± 63) µm inside the outer meniscus zone. Pore sizes of (82 ± 25) µm, (83 ± 29) µm and (85 ± 39) µm were present inside the subchondral, the lower chondral and the upper chondral zone of osteochondral scaffolds. Depending on the fabrication parameters, the respective scaffold zones were also found to feature a specific micro- and nanostructure at their inner surfaces.
Degradation studies were carried out under physiological conditions and resulted in a mean mass loss of (0.52 ± 0.13) %, (1.56 ± 0.10) % and (0.80 ± 0.10) % per day for bone, meniscus and osteochondral scaffolds, respectively. Rheological measurements were used to determine the viscosity changes upon cooling of different precursors. Micro computer tomography (µ-CT) investigations were applied to characterize the 3D microstructure of osteochondral scaffolds. To obtain an osteochondral scaffold with four zones of tissue mimetic microstructure alignment, a poly (D, L-lactide-co-glycolide) mesh was deposited on the upper chondral zone by electrostatic spinning. In case of the bone scaffolds, the retention / release capacity of bone morphogenetic protein 2 (BMP-2) was evaluated by an enzyme linked immunosorbent assay (ELISA). Due to the high presence of attractive BMP binding sites, only less than 0.1 % of the initially loaded cytokine was released. The suitability of combining the cryostructuring process with 3D powder printed calcium phosphate substrates was evaluated with osteochondral scaffolds, but did not appear to yield more preferable results than the non-combined approach.
A new custom build confined compression setup was elaborated together with a suitable evaluation procedure for the mechanical characterisation under physiological conditions. For bone and cartilage scaffolds, apparent elastic moduli of (37.6 ± 6.9) kPa and (3.14 ± 0.85) kPa were measured. A similar behaviour of the scaffolds to natural cartilage and bone tissue was demonstrated in terms of elastic energy storage. Under physiological frequencies, less than 1.0 % and 0.8 % of the exerted energy was lost for bone and cartilage scaffolds, respectively. With average relaxation times of (0.613 ± 0.040) sec and (0.815 ± 0.077) sec, measured for the cartilage and bone scaffolds, they respond four orders of magnitude faster than the native tissues. Additionally, all kinds of produced scaffolds were able to withstand cyclic compression at un-physiological frequencies as high as 20 Hz without a loss in structural integrity.
With the presented new method, scaffolds could be fabricated whose extent in mimicking of native tissues exceeded the one of scaffolds producible by state of the art methods. This allowed a testing of the key hypothesis: The biological evaluation of an anisotropic pore structure in vivo revealed a higher functionality of immigrated cells and led finally to advantageous healing outcomes. Moreover, the mimicking of local compositions in combination with a consecutive anisotropic porosity that approaches native tissue structures could be demonstrated to induce zone specific matrix remodelling in stem cells in vitro. Additionally, clues for a zone specific chondrogenic stem cell differentiation were attained without the supplementation of growth factors.
Thereby, the hypothesis that an increased approximation of the hierarchically compositional and structurally anisotropic properties of musculoskeletal tissues would lead to an improved cellular response and a better healing quality, could be confirmed. With a special focus on cell free in situ tissue engineering approaches, the insights gained within this thesis may be directly transferred to clinical regenerative therapies.
N2 - Die Schlüsselhypothese dieser Arbeit bestand darin zu überprüfen, ob eine Nachahmung der zonalen Zusammensetzungen und Porenstruktur muskulo-skelettaler Gewebe einwandernde Zellen beeinflusst und zu vorteilhafteren Ergebnissen im Tissue Engineering führt. Obwohl bereits zahlreiche konventionelle Ansätze existieren, so sind diese in ihrem Vermögen spezielle Zellträgermatrices („Scaffolds“) herzustellen limitiert. Insbesondere können dabei lokal variierende biologische Schlüsselreize nicht mit einer Porenstruktur, welche die Ausrichtung der Kollagenfasern in Knochen- und Knorpelgeweben imitiert, kombiniert werden. Um diese Lücke in den verfügbaren Tissue Engineering Strategien zu schließen, wurde ein neues Verfahren entwickelt. Dieses erlaubte die Herstellung monolithischer Scaffolds, welche eine Validierung der Hypothese ermöglichten.
Das neue Plattform-Verfahren basiert auf der gerichteten Erstarrung mehrerer fließfähiger Vorstufen, um somit eine kontrollierte anisotrope Porenstruktur vorzubereiten. Ein Entfernen der erstarrten Lösungsmittel durch Lyophilisation führt zu porösen Scaffolds. Optional besteht die Möglichkeit, Polymere mittels elektrostatischem Verspinnen als umhüllendes Vlies zu inkorporieren. Nach einem Vernetzungsschritt resultieren monolithische Matrices, bestehend aus mehreren Zonen mit unterschiedlichen Zusammensetzungen. Vor einer Verwendung als Tissue Engineering Matrix oder implantierbares Medizinprodukt erfolgt eine Sterilisation. Hierfür wurde ein “Adjustable Cryostructuring Device“ (ACD) entwickelt, einzelne Bauteile mit Computer Aided Design entworfen und zu einer Apparatur montiert. Die Optimierung der Anlage ermöglichte eine signifikante Erhöhung des verfügbaren externen Temperaturgradienten von (1.3 ± 0.1) K/mm auf (9.0 ± 0.1) K/mm. Außerdem erlauben vier unterschiedliche Konfigurationen des ACD die gerichtete Erstarrung von kollagenen Vorstufen in einer besonders kontrollierten Art und Weise bei einer Vielzahl an Probengrößen und Formen.
Die systematische Evaluation des Prozesses erfolgte mit Alginat als Modell-Substanz. Aus den zeitlichen Verläufen der Gefrierstrukturierung resultierten Erstarrungsparameter, die mittels Bildverarbeitung den entstandenen Porengrößen und -ausrichtungen zugeordnet wurden. Dies demonstrierte eine präzise Kontrolle der Ergebnisse durch elektrische Ansteuerung der ACD.
Zur Erzeugung von Rohmaterialien war eine Etablierung von Extraktions- und Aufreinigungsprotokollen für Kollagen I und Kollagen II notwendig, während eine Herstellung der Calciumphosphate Bruschit und Hydroxylapatit mittels Präzipitations-Reaktionen verlief. Neben der sukzessiven Verbesserung des ACD, stellte auch die Optimierung einzelner Prozessschritte wichtige Aspekte dar. Die Untersuchung und Diskussion des Verhaltens einzelner Vorstufenkomponenten sowie der Erstarrungs-phänomene von Kollagenlösungen führte zu einem Verständnis welches die Produktion von komplexeren Scaffolds zuließ. Somit war es auch möglich eine Abhängigkeitsrelation der einstellbaren Prozessparameter zu den resultierenden Erstarrungsmorphologien der verwendeten Kollagensysteme abzuleiten.
Die Gefrierstrukturierung von mehreren Lagen unterschiedlicher Vorstufen konnte erfolgreich von Alginat- auf Kollagenvorstufen transferiert werden. Nach einer Optimierung der jeweiligen Grenzflächenübergänge, waren diese selbst mittels Rasterelektronenmikroskopie kaum noch zu erkennen. Eine Evaluierung von dehydrothermal-, diisocyanat- und carbodiimid- basierten Quervernetzungs-methoden zeigte die vorteilhaftesten Ergebnisse für die Vernetzung durch Carbodiimide. Zusätzlich wurde eine Zusammensetzung der Vernetzungslösung ermittelt, welche beim Einsatz in einer Unterdruckapparatur einen Porenstrukturkollaps durch nasschemische Vernetzung vermeidet.
Eine erweiterte Kontrolle der Gefrierprozesse erlaubte es Struktur und Zusammensetzung verschiedener Zonen nativer Gewebe durch eine monolithische Zellträgermatrix mit durchgängiger Porenstruktur und biochemischen Schlüsselreizen nachzuahmen. Zuerst wurden drei Arten von Knochenscaffolds aus Kollagen I und Hydroxylapatit hergestellt, die Defekten kritischer Größe in Rattenoberschenkel-knochen entsprachen. Diese zeichneten sich durch eine isotrope oder eine anisotrope Porenstruktur aus und enthielten teilweise Glycosaminoglycane (GAGs). Weiterhin erfolgte die Produktion von Meniskusscaffolds aus zwei Vorstufen mit biomimetischen Anteilen an Kollagen I, Kollagen II und GAGs. Dabei verlief die Gefrierstrukturierung unter Grenzbedingungen, welche ein nahezu senkrechtes Eiskristallwachstum zu dem äußeren Temperaturgradienten erlaubten. Somit konnte der bevorzugte Verlauf von Kollagenfasern in nativem Meniskusgewebe nachgeahmt werden. Die Scaffolds waren entweder passend für „Well Plates“ der Zellkultur bemaßt oder besaßen sogar Form und Größe von authentischen Menisken.
Zuletzt wurden osteochondrale Scaffolds hergestellt, deren Zusammensetzung den jeweiligen Bereichen von Subchondralzone und verschiedenen Gelenkknorpelzonen entsprach. Kollagen I und die bioresorbierbare Calciumphosphatphase Bruschit fanden Verwendung in der Subchondralzone, während die Knorpelzonen aus Kollagen I, Kollagen II und entsprechenden biomimetischen Anteilen an GAGs bestanden. Außerdem bildete die Scaffoldporenstruktur die Volumendominierende in natürlichem Osteochondralgewebe nach, wobei die Dimensionierungen der Scaffolds Well Plates oder Perfusionsreaktoren der Zellkultur angepasst waren.
Mittels energiedispersiver Röntgenspektroskopie und Rasterelektronenmikroskopie erfolgte die Analyse von Zusammensetzung und Porenstruktur der jeweiligen Scaffoldzonen. Die Größe der Porenquerschnitte betrug (65 ± 25) µm, (88 ± 35) µm und (93 ± 42) µm für die anisotropen, die isotropen und die GAG-haltigen isotropen Knochenscaffolds. Die Meniskusscaffolds besaßen Porendurchmesser von
(93 ± 21) µm in der inneren Meniskuszone und (248 ± 63) µm innerhalb der äußeren Meniskuszone. Im Falle der osteochondralen Scaffolds wurden Porengrößen von
(82 ± 25) µm, (83 ± 29) µm und (85 ± 39) µm in der subchondralen, der unteren chondralen und der oberen chondralen Zone gemessen. In Abhängigkeit von den Prozessparametern zeigten die inneren Oberflächen der jeweiligen Scaffoldzonen eine spezifische Mikro- und Nanostruktur.
Eine Prüfung des Degradationsverhaltens unter physiologischen Bedingungen ergab einen mittleren Massenverlust von (0.52 ± 0.13) %, (1.56 ± 0.10) % und
(0.80 ± 0.10) % pro Tag für die Knochen-, Meniskus- und osteochondralen Scaffolds. Die Untersuchung der Viskositätsveränderungen während der Abkühlung unterschiedlicher Vorstufen geschah mit rheologischen Messungen. Weiterhin wurde die 3D Mikrostruktur von osteochondralen Matrices mit Mikro Computer Tomographie charakterisiert. Um einen osteochondralen Scaffold mit vier Zonen gewebeähnlich ausgerichteter Mikrostruktur zu erhalten, konnte die Scaffoldoberfläche durch ein elektroversponnenes Poly (D, L-Lactid-co-Glycolid) Vlies modifiziert werden.
Ein „enzyme linked immunosorbent assay“ (ELISA) diente zur Evaluation des Rückhalte- bzw. Freisetzungsverhaltens von „bone morphogenetic protein 2“
(BMP-2) in Knochenscaffolds. Bedingt durch die hohe Präsenz von attraktiven BMP Bindungsstellen betrug die freigesetzte Menge des initial beladenen Zytokins nur weniger als 0.1 %.
Die Eignung einer Kombination des Gefrierstrukturierungsprozesses mit 3D gedruckten Calciumphosphatsubstraten wurde anhand von osteochondralen Scaffolds überprüft, aber zeigte keine vorteilhafteren Resultate als die nicht kombinierte Vorgehensweise.
Für die mechanische Charakterisierung unter physiologischen Bedingungen konnte ein neues Test-Setup mitsamt Auswertungsverfahren entwickelt werden. Die gemessenen Elastizitätsmoduln betrugen (37.6 ± 6.9) kPa für Knochen- und (3.14 ± 0.85) kPa für Knorpelscaffolds. Da unter physiologischen Frequenzen nur weniger als 1.0 % der eingebrachten Energie verloren ging, entsprach die Fähigkeit der Zellträgermatrices zur elastischen Energiespeicherung dem von natürlichem Knochen- und Knorpelgewebe. Bei mittleren Relaxationszeiten von (0.613 ± 0.040) sec und (0.815 ± 0.077) sec für Knorpel- und Knochenscaffolds reagieren diese vier Größenordnungen schneller als die nativen Gewebe. Außerdem waren alle produzierten Matrices dazu in der Lage zyklischen Kompressionen bei unphysiologisch hohen Frequenzen von 20 Hz zu wiederstehen, ohne an struktureller Integrität zu verlieren.
Mit dem vorgestellten neuen Verfahren konnten Scaffolds hergestellt werden, deren Ausmaß in der Nachahmung nativer Gewebe mit etablierten Methoden nicht erreichbar war und welche eine Überprüfung der Schlüsselhypothese erlaubten: Die biologische Evaluation einer anisotropen Porenstruktur in vivo zeigte eine höhere Funktionalität eingewanderter Zellen, was zu vorteilhafteren Heilungsergebnissen führte. Darüber hinaus demonstrierte eine Imitation der lokalen Zusammensetzungen in Kombination mit einer durchgängigen anisotropen Porenstruktur, welche an diejenige in nativen Geweben angenähert ist, eine Induktion von zonenspezifischer Matrixremodellierung von Stammzellen in vitro. Außerdem waren Hinweise auf eine zonale chondrogene Stammzelldifferenzierung ohne eine gesonderte Zugabe von Wachstumsfaktoren zu beobachten.
Somit konnte die Hypothese, dass eine verbesserte Nachahmung der hierarchischen Zusammensetzung und anisotroper Struktur von muskuloskelettalen Geweben zu einer optimierten zellulären Reaktion und somit einer besseren Heilungsqualität führt, bestätigt werden. Mit einem speziellen Fokus auf zellfreies in situ Tissue Engineering, könnten die Erkenntnisse dieser Arbeit direkt für klinische Therapien eingesetzt werden.
KW - directional solidification
KW - collagen
KW - cartilage
KW - bone
KW - scaffold
KW - Tissue Engineering
KW - Knochen
KW - Knorpel
KW - Gerichtete Erstarrung
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-145510
ER -
TY - JOUR
A1 - Stritt, Simon
A1 - Nurden, Paquita
A1 - Favier, Remi
A1 - Favier, Marie
A1 - Ferioli, Silvia
A1 - Gotru, Sanjeev K.
A1 - van Eeuwijk, Judith M.M.
A1 - Schulze, Harald
A1 - Nurden, Alan T.
A1 - Lambert, Michele P.
A1 - Turro, Ernest
A1 - Burger-Stritt, Stephanie
A1 - Matsushita, Masayuki
A1 - Mittermeier, Lorenz
A1 - Ballerini, Paola
A1 - Zierler, Susanna
A1 - Laffan, Michael A.
A1 - Chubanov, Vladimir
A1 - Gudermann, Thomas
A1 - Nieswandt, Bernhard
A1 - Braun, Attila
T1 - Defects in TRPM7 channel function deregulate thrombopoiesis through altered cellular Mg\(^{2+}\) homeostasis and cytoskeletal architecture
JF - Nature Communications
N2 - Mg\(^{2+}\) plays a vital role in platelet function, but despite implications for life-threatening conditions such as stroke or myocardial infarction, the mechanisms controlling [Mg\(^{2+}\)]i in megakaryocytes (MKs) and platelets are largely unknown. Transient receptor potential melastatin-like 7 channel (TRPM7) is a ubiquitous, constitutively active cation channel with a cytosolic α-kinase domain that is critical for embryonic development and cell survival. Here we report that impaired channel function of TRPM7 in MKs causes macrothrombocytopenia in mice (Trpm7\(^{fl/fl-Pf4Cre}\)) and likely in several members of a human pedigree that, in addition, suffer from atrial fibrillation. The defect in platelet biogenesis is mainly caused by cytoskeletal alterations resulting in impaired proplatelet formation by Trpm7\(^{fl/fl-Pf4Cre}\) MKs, which is rescued by Mg\(^{2+}\) supplementation or chemical inhibition of non-muscle myosin IIA heavy chain activity. Collectively, our findings reveal that TRPM7 dysfunction may cause macrothrombocytopenia in humans and mice.
KW - Cytoskeleton
KW - homeostasisIon channels
KW - thrombopoiesis
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-173843
VL - 7
ER -
TY - JOUR
A1 - Strekalova, Tatyana
A1 - Markova, Nataliia
A1 - Shevtsova, Elena
A1 - Zubareva, Olga
A1 - Bakhmet, Anastassia
A1 - Steinbusch, Harry M.
A1 - Bachurin, Sergey
A1 - Lesch, Klaus-Peter
T1 - Individual Differences in Behavioural Despair Predict Brain GSK-3beta Expression in Mice: The Power of a Modified Swim Test
JF - Neural Plasticity
N2 - While deficient brain plasticity is a well-established pathophysiologic feature of depression, little is known about disorder-associated enhanced cognitive processing. Here, we studied a novel mouse paradigm that potentially models augmented learning of adverse memories during development of a depressive-like state. We used a modification of the classic two-day protocol of a mouse Porsolt test with an additional session occurring on Day 5 following the initial exposure. Unexpectedly, floating behaviour and brain glycogen synthase kinase-3 beta (GSK-3beta) mRNA levels, a factor of synaptic plasticity as well as a marker of distress and depression, were increased during the additional swimming session that was prevented by imipramine. Observed increases of GSK-3beta mRNA in prefrontal cortex during delayed testing session correlated with individual parameters of behavioural despair that was not found in the classic Porsolt test. Repeated swim exposure was accompanied by a lower pGSK-3beta/GSK-3beta ratio. A replacement of the second or the final swim sessions with exposure to the context of testing resulted in increased GSK-3beta mRNA level similar to the effects of swimming, while exclusion of the second testing prevented these changes. Together, our findings implicate the activation of brain GSK-3beta expression in enhanced contextual conditioning of adverse memories, which is associated with an individual susceptibility to a depressive syndrome.
KW - mice
KW - swim test
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147379
VL - 2016
ER -
TY - JOUR
A1 - Stolze, Ina
A1 - Trautmann, Axel
A1 - Goebeler, Matthias
A1 - Stoevesandt, Johanna
T1 - Dangerous Leg Cramps: Severe Pustular Exanthema Caused by an Over-the-Counter Drug
JF - Acta Dermato-Venereologica
N2 - Abstract is missing
KW - leg cramps
KW - over-the-counter drugs
KW - pustular exanthema
KW - quinine
KW - allergy
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171285
VL - 96
ER -
TY - JOUR
A1 - Stoeckel, M. Cornelia
A1 - Esser, Roland W.
A1 - Gamer, Matthias
A1 - Büchel, Christian
A1 - von Leupoldt, Andreas
T1 - Brain Responses during the Anticipation of Dyspnea
JF - Neural Plasticity
N2 - Dyspnea is common in many cardiorespiratory diseases. Already the anticipation of this aversive symptom elicits fear in many patients resulting in unfavorable health behaviors such as activity avoidance and sedentary lifestyle. This study investigated brain mechanisms underlying these anticipatory processes. We induced dyspnea using resistive-load breathing in healthy subjects during functional magnetic resonance imaging. Blocks of severe and mild dyspnea alternated, each preceded by anticipation periods. Severe dyspnea activated a network of sensorimotor, cerebellar, and limbic areas. The left insular, parietal opercular, and cerebellar cortices showed increased activation already during dyspnea anticipation. Left insular and parietal opercular cortex showed increased connectivity with right insular and anterior cingulate cortex when severe dyspnea was anticipated, while the cerebellum showed increased connectivity with the amygdala. Notably, insular activation during dyspnea perception was positively correlated with midbrain activation during anticipation. Moreover, anticipatory fear was positively correlated with anticipatory activation in right insular and anterior cingulate cortex. The results demonstrate that dyspnea anticipation activates brain areas involved in dyspnea perception. The involvement of emotion-related areas such as insula, anterior cingulate cortex, and amygdala during dyspnea anticipation most likely reflects anticipatory fear and might underlie the development of unfavorable health behaviors in patients suffering from dyspnea.
KW - brain response
KW - dyspnea
KW - cardiorespiratory disease
KW - anticipation
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166238
VL - 2016
IS - 6434987
ER -
TY - JOUR
A1 - Stock, Nina Katharina
A1 - Petráš, Petr
A1 - Melter, Oto
A1 - Kapounová, Gabriela
A1 - Vopalková, Petra
A1 - Kubele, Jan
A1 - Vaniš, Václav
A1 - Tkadlec, Jan
A1 - Bukáčková, Eva
A1 - Machová, Ivana
A1 - Jindrák, Vlastimil
T1 - Importance of Multifaceted Approaches in Infection Control: A Practical Experience from an Outbreak Investigation
JF - PLoS ONE
N2 - Background
This study presents the results of a multidisciplinary, nosocomial MRSA outbreak investigation in an 8-bed medical intensive care unit (ICU). The identification of seven MRSA positive patients in the beginning of 2014 led to the closure of the ward for several weeks. A multidisciplinary, retrospective investigation was initiated in order to identify the reason and the source for the outbreak, describe MRSA transmission in the department and identify limitations in infection control.
Methods
The investigation comprised an epidemiological description of MRSA cases from 2012 to 2014 and a characterization of MRSA isolates, including phage-, spa- and PFGE-typing. Additionally, MRSA screening was performed from the hospital staff and the environment. To identify the reason for the outbreak, work-related, psychological and behavioral factors were investigated by impartial audits and staff interviews.
Results
Thirty-one MRSA cases were registered during the study period, and 36 isolates were investigated. Molecular typing determined the outbreak strain (phage type 54/812, PFGE type A4, spa type t003) and identified the probable index case. Nasal carriage in one employee and a high environmental contamination with the outbreak strain was documented. Important gaps in nursing procedures and general management were identified. Elevated stress levels and communication problems preceded the outbreak. Compliance with hand hygiene and isolation procedures was evaluated as appropriate.
Conclusion
This study demonstrates the complexity of controlling hospital-associated infections. The combined use of different typing methods is beneficial for outbreak investigations. Psychological, behavioral and other work-related factors have an important impact on the spread of nosocomial pathogens. These factors should be addressed and integrated in routine infection control practice.
KW - multifaceted approaches
KW - infection control
KW - Methicillin resistant Staphylococcus aureus
KW - MRSA
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166891
VL - 11
IS - 6
ER -
TY - JOUR
A1 - Sterkenburg, Anthe S.
A1 - Hoffmann, Anika
A1 - Reichel, Julia
A1 - Lohle, Kristin
A1 - Eveslage, Maria
A1 - Warmuth-Metz, Monika
A1 - Müller, Hermann L.
T1 - Nuchal skinfold thickness: A novel parameter for assessment of body composition in childhood craniopharyngioma
JF - Journal of Clinical Endocrinology & Metabolism
N2 - Context:
Hypothalamic obesity, cardiovascular disease (CVD), and relapse/progression have a major impact on prognosis in childhood-onset craniopharyngioma (CP). We analyzed nuchal skinfold thickness (NST) on magnetic resonance imaging performed for follow-up monitoring as a novel parameter for body composition (BC) and CVD in CP.
Objective:
The objective of the study was to identify the association of NST with body mass index (BMI), waist to height ratio (WHtR), functional capacity, and blood pressure (BP) in CP and controls.
Design:
This was a cross-sectional and longitudinal prospective study in CP patients. Setting: The study was conducted at HIT-Endo, KRANIOPHARYNGEOM 2000/2007.
Patients:
Participants included 94 CP patients and 75 controls.
Interventions:
There were no interventions.
Main Outcome Measures:
Association of NST with BC and BP in 43 CP and 43 controls was measured.
Results:
NST correlated with BMI SD score (SDS; r = 0.78; P = .001; n = 169) and WHtR (r = 0.85; P = .001; n = 86) in the total cohort and CP patients (NST-BMI SDS: r = 0.77, P = .001, n = 94); NST-WHtR: r = 0.835, P = .001, n = 43) and controls (NST-BMI SDS: r = 0.792, P = .001, n = 75; NST-WHtR: r = 0.671, P = .001, n = 43). In CP, systolic BP correlated with NST (r = 0.575, P = .001), BMI SDS (r = 0.434, P = .004), and WHtR (r = 0.386, P = .011). Similar results were observed for diastolic BP in CP. In multivariate analyses, NST had a predictive value for hypertension in postpubertal CP and controls (odds ratio 6.98, 95% confidence interval 1.65, 29.5], P = .008). During a longitudinal follow-up, changes in NST correlated with changes in BMI SDS (P = .001) and WHtR (P = .01) but not with changes in BP and functional capacity.
Conclusions:
Because monitoring of magnetic resonance imaging and BC is essential for follow-up in CP, NST could serve as a novel and clinically relevant parameter for longitudinal assessment of BC and CVD risk in CP.
KW - to-height ratio
KW - subcutaneous adipose-tissue
KW - disease risk-factors
KW - long-term survivors
KW - guality-of-life
KW - mass index
KW - neck circumference
KW - onset craniopharyngioma
KW - german multicenter
KW - visceral adiposity
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-186562
VL - 101
IS - 12
ER -
TY - JOUR
A1 - Stein, Roland Gregor
A1 - Wollschläger, Daniel
A1 - Kreienberg, Rolf
A1 - Janni, Wolfgang
A1 - Wischnewsky, Manfred
A1 - Diessner, Joachim
A1 - Stüber, Tanja
A1 - Bartmann, Catharina
A1 - Krockenberger, Mathias
A1 - Wischhusen, Jörg
A1 - Wöckel, Achim
A1 - Blettner, Maria
A1 - Schwentner, Lukas
T1 - The impact of breast cancer biological subtyping on tumor size assessment by ultrasound and mammography - a retrospective multicenter cohort study of 6543 primary breast cancer patients
JF - BMC Cancer
N2 - Background
Mammography and ultrasound are the gold standard imaging techniques for preoperative assessment and for monitoring the efficacy of neoadjuvant chemotherapy in breast cancer. Maximum accuracy in predicting pathological tumor size non-invasively is critical for individualized therapy and surgical planning. We therefore aimed to assess the accuracy of tumor size measurement by ultrasound and mammography in a multicentered health services research study.
Methods
We retrospectively analyzed data from 6543 patients with unifocal, unilateral primary breast cancer. The maximum tumor diameter was measured by ultrasound and/or mammographic imaging. All measurements were compared to final tumor diameter determined by postoperative histopathological examination. We compared the precision of each imaging method across different patient subgroups as well as the method-specific accuracy in each patient subgroup.
Results
Overall, the correlation with histology was 0.61 for mammography and 0.60 for ultrasound. Both correlations were higher in pT2 cancers than in pT1 and pT3. Ultrasound as well as mammography revealed a significantly higher correlation with histology in invasive ductal compared to lobular cancers (p < 0.01). For invasive lobular cancers, the mammography showed better correlation with histology than ultrasound (p = 0.01), whereas there was no such advantage for invasive ductal cancers. Ultrasound was significantly superior for HR negative cancers (p < 0.001). HER2/neu positive cancers were also more precisely assessed by ultrasound (p < 0.001). The size of HER2/neu negative cancers could be more accurately predicted by mammography (p < 0.001).
Conclusion
This multicentered health services research approach demonstrates that predicting tumor size by mammography and ultrasound provides accurate results. Biological tumor features do, however, affect the diagnostic precision.
KW - histopathology
KW - breast cancer
KW - ultrasound
KW - mammography
KW - tumor size
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161050
VL - 16
IS - 549
ER -
TY - JOUR
A1 - Steigerwald, Frank
A1 - Müller, Lorenz
A1 - Johannes, Silvia
A1 - Matthies, Cordula
A1 - Volkmann, Jens
T1 - Directional deep brain stimulation of the subthalamic nucleus: a pilot study using a novel neurostimulation device
JF - Movement Disorders
N2 - Introduction
A novel neurostimulation system allows steering current in horizontal directions by combining segmented leads and multiple independent current control. The aim of this study was to evaluate directional DBS effects on parkinsonian motor features and adverse effects of subthalamic neurostimulation.
Methods
Seven PD patients implanted with the novel directional DBS system for bilateral subthalamic DBS underwent an extended monopolar review session during the first postoperative week, in which current thresholds were determined for rigidity control and stimulation-induced adverse effects using either directional or ring-mode settings.
Results
Effect or adverse effect thresholds were modified by directional settings for each of the 14 STN leads. Magnitude of change varied markedly between leads, as did orientation of optimal horizontal current steering.
Conclusion
Directional current steering through chronically implanted segmented electrodes is feasible, alters adverse effect and efficacy thresholds in a highly individual manner, and expands the therapeutic window in a monopolar review as compared to ring-mode DBS.
KW - deep brain stimulation
KW - Parkinson's disease
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187683
VL - 31
IS - 8
ER -
TY - JOUR
A1 - Stauss, Dennis
A1 - Brunner, Cornelia
A1 - Berberich-Siebelt, Friederike
A1 - Höpken, Uta E.
A1 - Lipp, Martin
A1 - Müller, Gerd
T1 - The transcriptional coactivator Bob1 promotes the development of follicular T helper cells via Bcl6
JF - Embo Journal
N2 - Follicular T helper (Tfh) cells are key regulators of the germinal center reaction and long-term humoral immunity. Tfh cell differentiation requires the sustained expression of the transcriptional repressor Bcl6; however, its regulation in CD4\(^+\) T cells is incompletely understood. Here, we report that the transcriptional coactivator Bob1, encoded by the Pou2af1 gene, promotes Bcl6 expression and Tfh cell development. We found that Bob1 together with the octamer transcription factors Oct1/Oct2 can directly bind to and transactivate the Bcl6 and Btla promoters. Mixed bone marrow chimeras revealed that Bob1 is required for the expression of normal levels of Bcl6 and BTLA, thereby controlling the pool size and composition of the Tfh compartment in a T cell-intrinsic manner. Our data indicate that T cell-expressed Bob1 is directly involved in Tfh cell differentiation and required for mounting normal T cell-dependent B-cell responses.
KW - follicular T helper cells
KW - germinal center
KW - humoral immunity
KW - Pou2af1
KW - T cell differentiation
Y1 - 2016
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189506
VL - 35
IS - 8
ER -