TY - JOUR
A1 - Yu, Yidong
A1 - Wolf, Ann-Katrin
A1 - Thusek, Sina
A1 - Heinekamp, Thorsten
A1 - Bromley, Michael
A1 - Krappmann, Sven
A1 - Terpitz, Ulrich
A1 - Voigt, Kerstin
A1 - Brakhage, Axel A.
A1 - Beilhack, Andreas
T1 - Direct Visualization of Fungal Burden in Filamentous Fungus-Infected Silkworms
JF - Journal of Fungi
N2 - Invasive fungal infections (IFIs) are difficult to diagnose and to treat and, despite several available antifungal drugs, cause high mortality rates. In the past decades, the incidence of IFIs has continuously increased. More recently, SARS-CoV-2-associated lethal IFIs have been reported worldwide in critically ill patients. Combating IFIs requires a more profound understanding of fungal pathogenicity to facilitate the development of novel antifungal strategies. Animal models are indispensable for studying fungal infections and to develop new antifungals. However, using mammalian animal models faces various hurdles including ethical issues and high costs, which makes large-scale infection experiments extremely challenging. To overcome these limitations, we optimized an invertebrate model and introduced a simple calcofluor white (CW) staining protocol to macroscopically and microscopically monitor disease progression in silkworms (Bombyx mori) infected with the human pathogenic filamentous fungi Aspergillus fumigatus and Lichtheimia corymbifera. This advanced silkworm A. fumigatus infection model could validate knockout mutants with either attenuated, strongly attenuated or unchanged virulence. Finally, CW staining allowed us to efficiently visualize antifungal treatment outcomes in infected silkworms. Conclusively, we here present a powerful animal model combined with a straightforward staining protocol to expedite large-scale in vivo research of fungal pathogenicity and to investigate novel antifungal candidates.
KW - fungal infection model
KW - calcofluor white staining
KW - Aspergillus
KW - Lichtheimia
KW - silkworm
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228855
SN - 2309-608X
VL - 7
IS - 2
ER -
TY - JOUR
A1 - Kelm, Matthias
A1 - Anger, Friedrich
A1 - Eichlinger, Robin
A1 - Brand, Markus
A1 - Kim, Mia
A1 - Reibetanz, Joachim
A1 - Krajinovic, Katica
A1 - Germer, Christoph-Thomas
A1 - Schlegel, Nicolas
A1 - Flemming, Sven
T1 - Early Ileocecal Resection Is an Effective Therapy in Isolated Crohn’s Disease
JF - Journal of Clinical Medicine
N2 - Despite the increasing incidence and prevalence of Crohn’s Disease (CD), no curative options exist and treatment remains complex. While therapy has mainly focused on medical approaches in the past, growing evidence reveals that in cases of limited inflammation, surgery can suffice as an alternative primary treatment. We retrospectively assessed the disease course and outcomes of 103 patients with terminal Ileitis who underwent primary surgery (n = 29) or received primary medical treatment followed by surgery (n = 74). Primary endpoint was the need for immunosuppressive medication after surgical treatment (ileocecal resection, ICR) during a two-years follow-up. Rates for laparoscopic ICR were enhanced in case of early surgery, but no differences were seen for postoperative complications. In case of immunosuppressive medication, patients with ICR at an early state of disease needed significantly less anti-inflammatory medication during the two-year postoperative follow-up compared to patients who were primarily treated medically. Furthermore, in a subgroup analysis for patients with localized ileocecal disease manifestation, early surgery consistently resulted in a decreased amount of medical therapy postoperatively. In conclusion primary ICR is safe and effective in patients with limited CD, and the need for immunosuppressive medication during the postoperative follow-up is low compared to patients receiving surgery at a later stage of disease.
KW - Crohn’s Disease
KW - surgical therapy
KW - ileocecal resection
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228822
SN - 2077-0383
VL - 10
IS - 4
ER -
TY - JOUR
A1 - Detomas, Mario
A1 - Altieri, Barbara
A1 - Schlötelburg, Wiebke
A1 - Appenzeller, Silke
A1 - Schlaffer, Sven
A1 - Coras, Roland
A1 - Schirbel, Andreas
A1 - Wild, Vanessa
A1 - Kroiss, Matthias
A1 - Sbiera, Silviu
A1 - Fassnacht, Martin
A1 - Deutschbein, Timo
T1 - Case Report: Consecutive Adrenal Cushing’s Syndrome and Cushing’s Disease in a Patient With Somatic CTNNB1, USP8, and NR3C1 Mutations
JF - Frontiers in Endocrinology
N2 - The occurrence of different subtypes of endogenous Cushing’s syndrome (CS) in single individuals is extremely rare. We here present the case of a female patient who was successfully cured from adrenal CS 4 years before being diagnosed with Cushing’s disease (CD). The patient was diagnosed at the age of 50 with ACTH-independent CS and a left-sided adrenal adenoma, in January 2015. After adrenalectomy and histopathological confirmation of a cortisol-producing adrenocortical adenoma, biochemical hypercortisolism and clinical symptoms significantly improved. However, starting from 2018, the patient again developed signs and symptoms of recurrent CS. Subsequent biochemical and radiological workup suggested the presence of ACTH-dependent CS along with a pituitary microadenoma. The patient underwent successful transsphenoidal adenomectomy, and both postoperative adrenal insufficiency and histopathological workup confirmed the diagnosis of CD. Exome sequencing excluded a causative germline mutation but showed somatic mutations of the β-catenin protein gene (CTNNB1) in the adrenal adenoma, and of both the ubiquitin specific peptidase 8 (USP8) and the glucocorticoid receptor (NR3C1) genes in the pituitary adenoma. In conclusion, our case illustrates that both ACTH-independent and ACTH-dependent CS may develop in a single individual even without evidence for a common genetic background.
KW - Cushing’s syndrome
KW - Cushing’s disease
KW - hypercortisolism
KW - glucocorticoid excess
KW - USP8
KW - CTNNB1
KW - NR3C1
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244596
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Link, Fabian
A1 - Borges, Alyssa R.
A1 - Jones, Nicola G.
A1 - Engstler, Markus
T1 - To the Surface and Back: Exo- and Endocytic Pathways in Trypanosoma brucei
JF - Frontiers in Cell and Developmental Biology
N2 - Trypanosoma brucei is one of only a few unicellular pathogens that thrives extracellularly in the vertebrate host. Consequently, the cell surface plays a critical role in both immune recognition and immune evasion. The variant surface glycoprotein (VSG) coats the entire surface of the parasite and acts as a flexible shield to protect invariant proteins against immune recognition. Antigenic variation of the VSG coat is the major virulence mechanism of trypanosomes. In addition, incessant motility of the parasite contributes to its immune evasion, as the resulting fluid flow on the cell surface drags immunocomplexes toward the flagellar pocket, where they are internalized. The flagellar pocket is the sole site of endo- and exocytosis in this organism. After internalization, VSG is rapidly recycled back to the surface, whereas host antibodies are thought to be transported to the lysosome for degradation. For this essential step to work, effective machineries for both sorting and recycling of VSGs must have evolved in trypanosomes. Our understanding of the mechanisms behind VSG recycling and VSG secretion, is by far not complete. This review provides an overview of the trypanosome secretory and endosomal pathways. Longstanding questions are pinpointed that, with the advent of novel technologies, might be answered in the near future.
KW - cell surface
KW - African trypanosomes
KW - endocytosis
KW - exocytosis
KW - membrane recycling
KW - Rab
KW - clathrin
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244682
SN - 2296-634X
VL - 9
ER -
TY - JOUR
A1 - Krajka, Victor
A1 - Naujock, Maximilian
A1 - Pauly, Martje G.
A1 - Stengel, Felix
A1 - Meier, Britta
A1 - Stanslowsky, Nancy
A1 - Klein, Christine
A1 - Seibler, Philip
A1 - Wegner, Florian
A1 - Capetian, Philipp
T1 - Ventral Telencephalic Patterning Protocols for Induced Pluripotent Stem Cells
JF - Frontiers in Cell and Developmental Biology
N2 - The differentiation of human induced pluripotent stem cells (hiPSCs) into specific cell types for disease modeling and restorative therapies is a key research agenda and offers the possibility to obtain patient-specific cells of interest for a wide range of diseases. Basal forebrain cholinergic neurons (BFCNs) play a particular role in the pathophysiology of Alzheimer’s dementia and isolated dystonias. In this work, various directed differentiation protocols based on monolayer neural induction were tested for their effectiveness in promoting a ventral telencephalic phenotype and generating BFCN. Ventralizing factors [i.e., purmorphamine and Sonic hedgehog (SHH)] were applied at different time points, time intervals, and concentrations. In addition, caudal identity was prevented by the use of a small molecule XAV-939 that inhibits the Wnt-pathway. After patterning, gene expression profiles were analyzed by quantitative PCR (qPCR). Rostro-ventral patterning is most effective when initiated simultaneously with neural induction. The most promising combination of patterning factors was 0.5 μM of purmorphamine and 1 μM of XAV-939, which induces the highest expression of transcription factors specific for the medial ganglionic eminence, the source of GABAergic inter- and cholinergic neurons in the telencephalon. Upon maturation of cells, the immune phenotype, as well as electrophysiological properties were investigated showing the presence of marker proteins specific for BFCN (choline acetyltransferase, ISL1, p75, and NKX2.1) and GABAergic neurons. Moreover, a considerable fraction of measured cells displayed mature electrophysiological properties. Synaptic boutons containing the vesicular acetylcholine transporter (VACHT) could be observed in the vicinity of the cells. This work will help to generate basal forebrain interneurons from hiPSCs, providing a promising platform for modeling neurological diseases, such as Alzheimer’s disease or Dystonia.
KW - induced pluripotent stem cells
KW - medial ganglionic eminence
KW - Sonic hedgehog
KW - XAV-939
KW - purmorphamine
KW - basal forebrain cholinergic neurons
KW - GABAergic neurons
KW - electrophysiology
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244607
SN - 2296-634X
VL - 9
ER -
TY - JOUR
A1 - Adam, Pia
A1 - Kircher, Stefan
A1 - Sbiera, Iuliu
A1 - Koehler, Viktoria Florentine
A1 - Berg, Elke
A1 - Knösel, Thomas
A1 - Sandner, Benjamin
A1 - Fenske, Wiebke Kristin
A1 - Bläker, Hendrik
A1 - Smaxwil, Constantin
A1 - Zielke, Andreas
A1 - Sipos, Bence
A1 - Allelein, Stephanie
A1 - Schott, Matthias
A1 - Dierks, Christine
A1 - Spitzweg, Christine
A1 - Fassnacht, Martin
A1 - Kroiss, Matthias
T1 - FGF-Receptors and PD-L1 in Anaplastic and Poorly Differentiated Thyroid Cancer: Evaluation of the Preclinical Rationale
JF - Frontiers in Endocrinology
N2 - Background
Treatment options for poorly differentiated (PDTC) and anaplastic (ATC) thyroid carcinoma are unsatisfactory and prognosis is generally poor. Lenvatinib (LEN), a multi-tyrosine kinase inhibitor targeting fibroblast growth factor receptors (FGFR) 1-4 is approved for advanced radioiodine refractory thyroid carcinoma, but response to single agent is poor in ATC. Recent reports of combining LEN with PD-1 inhibitor pembrolizumab (PEM) are promising.
Materials and Methods
Primary ATC (n=93) and PDTC (n=47) tissue samples diagnosed 1997-2019 at five German tertiary care centers were assessed for PD-L1 expression by immunohistochemistry using Tumor Proportion Score (TPS). FGFR 1-4 mRNA was quantified in 31 ATC and 14 PDTC with RNAscope in-situ hybridization. Normal thyroid tissue (NT) and papillary thyroid carcinoma (PTC) served as controls. Disease specific survival (DSS) was the primary outcome variable.
Results
PD-L1 TPS≥50% was observed in 42% of ATC and 26% of PDTC specimens. Mean PD-L1 expression was significantly higher in ATC (TPS 30%) than in PDTC (5%; p<0.01) and NT (0%, p<0.001). 53% of PDTC samples had PD-L1 expression ≤5%. FGFR mRNA expression was generally low in all samples but combined FGFR1-4 expression was significantly higher in PDTC and ATC compared to NT (each p<0.001). No impact of PD-L1 and FGFR 1-4 expression was observed on DSS.
Conclusion
High tumoral expression of PD-L1 in a large proportion of ATCs and a subgroup of PDTCs provides a rationale for immune checkpoint inhibition. FGFR expression is low thyroid tumor cells. The clinically observed synergism of PEM with LEN may be caused by immune modulation.
KW - tyrosine kinase inhibitor (TKI)
KW - immune checkpoint inhibitor (ICI)
KW - immunohistochemistry
KW - immunotherapy
KW - PD-L1
KW - FGFR
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244653
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Gentzsch, Christian
A1 - Hoffmann, Matthias
A1 - Ohshima, Yasuhiro
A1 - Nose, Naoko
A1 - Chen, Xinyu
A1 - Higuchi, Takahiro
A1 - Decker, Michael
T1 - Synthesis and Initial Characterization of a Selective, Pseudo‐irreversible Inhibitor of Human Butyrylcholinesterase as PET Tracer
JF - ChemMedChem
N2 - The enzyme butyrylcholinesterase (BChE) represents a promising target for imaging probes to potentially enable early diagnosis of neurodegenerative diseases like Alzheimer's disease (AD) and to monitor disease progression in some forms of cancer. In this study, we present the design, facile synthesis, in vitro and preliminary ex vivo and in vivo evaluation of a morpholine‐based, selective inhibitor of human BChE as a positron emission tomography (PET) tracer with a pseudo‐irreversible binding mode. We demonstrate a novel protecting group strategy for 18F radiolabeling of carbamate precursors and show that the inhibitory potency as well as kinetic properties of our unlabeled reference compound were retained in comparison to the parent compound. In particular, the prolonged duration of enzyme inhibition of such a morpholinocarbamate motivated us to design a PET tracer, possibly enabling a precise mapping of BChE distribution.
KW - carbamate
KW - enzyme kinetics
KW - fluorine-18
KW - positron emission tomography
KW - radiotracers
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239904
VL - 16
IS - 9
SP - 1427
EP - 1437
ER -
TY - JOUR
A1 - Li, Kunkun
A1 - Prada, Juan
A1 - Damineli, Daniel S. C.
A1 - Liese, Anja
A1 - Romeis, Tina
A1 - Dandekar, Thomas
A1 - Feijó, José A.
A1 - Hedrich, Rainer
A1 - Konrad, Kai Robert
T1 - An optimized genetically encoded dual reporter for simultaneous ratio imaging of Ca\(^{2+}\) and H\(^{+}\) reveals new insights into ion signaling in plants
JF - New Phytologist
N2 - Whereas the role of calcium ions (Ca\(^{2+}\)) in plant signaling is well studied, the physiological significance of pH‐changes remains largely undefined.
Here we developed CapHensor, an optimized dual‐reporter for simultaneous Ca\(^{2+}\) and pH ratio‐imaging and studied signaling events in pollen tubes (PTs), guard cells (GCs), and mesophyll cells (MCs). Monitoring spatio‐temporal relationships between membrane voltage, Ca\(^{2+}\)‐ and pH‐dynamics revealed interconnections previously not described.
In tobacco PTs, we demonstrated Ca\(^{2+}\)‐dynamics lag behind pH‐dynamics during oscillatory growth, and pH correlates more with growth than Ca\(^{2+}\). In GCs, we demonstrated abscisic acid (ABA) to initiate stomatal closure via rapid cytosolic alkalization followed by Ca2+ elevation. Preventing the alkalization blocked GC ABA‐responses and even opened stomata in the presence of ABA, disclosing an important pH‐dependent GC signaling node. In MCs, a flg22‐induced membrane depolarization preceded Ca2+‐increases and cytosolic acidification by c. 2 min, suggesting a Ca\(^{2+}\)/pH‐independent early pathogen signaling step. Imaging Ca2+ and pH resolved similar cytosol and nuclear signals and demonstrated flg22, but not ABA and hydrogen peroxide to initiate rapid membrane voltage‐, Ca\(^{2+}\)‐ and pH‐responses.
We propose close interrelation in Ca\(^{2+}\)‐ and pH‐signaling that is cell type‐ and stimulus‐specific and the pH having crucial roles in regulating PT growth and stomata movement.
KW - abscisic acid (ABA)
KW - calcium
KW - flg22
KW - guard cells
KW - imaging
KW - ion signaling
KW - pH
KW - pollen tube
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239847
VL - 230
IS - 6
SP - 2292
EP - 2310
ER -
TY - JOUR
A1 - Kriegel, Peter
A1 - Fritze, Michael‐Andreas
A1 - Thorn, Simon
T1 - Surface temperature and shrub cover drive ground beetle (Coleoptera: Carabidae) assemblages in short‐rotation coppices
JF - Agricultural and Forest Entomology
N2 - Increasing demand for biomass has led to an on‐going intensification of fuel wood plantations with possible negative effects on open land biodiversity. Hence, ecologists increasingly call for measures that reduce those negative effects on associated biodiversity. However, our knowledge about the efficiency of such measures remains scarce.
We investigated the effects of gap implementation in short rotation coppices (SRCs) on carabid diversity and assemblage composition over 3 years, with pitfall traps in gaps, edges and interiors. In parallel, we quantified soil surface temperature, shrub‐ and herb cover.
Edges had the highest number of species and abundances per trap, whereas rarefied species richness was significantly lower in short rotation coppice interiors than in other habitat types. Carabid community composition differed significantly between habitat types. The main environmental drivers were temperature for number of species and abundance and shrub cover for rarefied species richness.
We found significantly higher rarefied species richness in gaps compared with interiors. Hence, we argue that gap implementation benefits overall diversity in short rotation coppices. Furthermore, the differences in species community composition between habitat types through increased species turnover support carabid diversity in short rotation coppices. These positive effects were largely attributed to microclimate conditions. However, to maintain positive effects, continuous management of herb layer might be necessary.
KW - Carabidae
KW - fuel wood
KW - short‐rotation coppice
KW - shrub‐cover
KW - temperature
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239873
VL - 23
IS - 4
SP - 400
EP - 410
ER -
TY - JOUR
A1 - Schroer, Guido
A1 - Toussaint, Valérie
A1 - Bachmann, Stephanie
A1 - Pöppler, Ann‐Christin
A1 - Gierlich, Christian Henning
A1 - Delidovich, Irina
T1 - Functional Phenylboronate Polymers for the Recovery of Diols, Sugar Alcohols, and Saccharides from Aqueous Solution
JF - ChemSusChem
N2 - The ongoing transition from fossil to renewable feedstocks demands new efficient processes for an economically viable production of biomass‐derived commodities and fine chemicals. Novel energy‐ and material‐efficient product purification and separation will play a crucial role due to altered product and feed composition. The present study comprises the synthesis and tests of cross‐linked p‐vinylphenylboronate polymers for the separation of 18 diols, sugar alcohols, and saccharides, which can be obtained during biomass processing. The separation was based on molecular recognition, that is, esterification of the phenylboronate with vicinal diols. A correlation of the molecular complexation constant, the polymer swelling, and the maximum adsorption capacity was found. The adsorption curves over time were recorded. Preliminary results on competitive adsorption of binary mixtures showed a high potential for the separation of substrates with significantly different complexation constants. Desorption tests implied easier desorption of substrates that only adsorb on the outer polymer shell.
KW - adsorption
KW - biomass
KW - phenylboronate
KW - polymers
KW - separation techniques
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239889
VL - 14
IS - 23
SP - 5207
EP - 5215
ER -
TY - JOUR
A1 - Emmerich, Petra
A1 - Murawski, Carolin
A1 - Ehmen, Christa
A1 - von Possel, Ronald
A1 - Pekarek, Neele
A1 - Oestereich, Lisa
A1 - Duraffour, Sophie
A1 - Pahlmann, Meike
A1 - Struck, Nicole
A1 - Eibach, Daniel
A1 - Krumkamp, Ralf
A1 - Amuasi, John
A1 - Maiga‐Ascofaré, Oumou
A1 - Rakotozandrindrainy, Raphael
A1 - Asogun, Danny
A1 - Ighodalo, Yemisi
A1 - Kann, Simone
A1 - May, Jürgen
A1 - Tannich, Egbert
A1 - Deschermeier, Christina
T1 - Limited specificity of commercially available SARS‐CoV‐2 IgG ELISAs in serum samples of African origin
JF - Tropical Medicine & International Health
N2 - Objectives
Specific serological tests are mandatory for reliable SARS‐CoV‐2 diagnostics and seroprevalence studies. Here, we assess the specificities of four commercially available SARS‐CoV‐2 IgG ELISAs in serum/plasma panels originating from Africa, South America, and Europe.
Methods
882 serum/plasma samples collected from symptom‐free donors before the COVID‐19 pandemic in three African countries (Ghana, Madagascar, Nigeria), Colombia, and Germany were analysed with three nucleocapsid‐based ELISAs (Euroimmun Anti‐SARS‐CoV‐2‐NCP IgG, EDI™ Novel Coronavirus COVID‐19 IgG, Mikrogen recomWell SARS‐CoV‐2 IgG), one spike/S1‐based ELISA (Euroimmun Anti‐SARS‐CoV‐2 IgG), and in‐house common cold CoV ELISAs.
Results
High specificity was confirmed for all SARS‐CoV‐2 IgG ELISAs for Madagascan (93.4–99.4%), Colombian (97.8–100.0%), and German (95.9–100.0%) samples. In contrast, specificity was much lower for the Ghanaian and Nigerian serum panels (Ghana: NCP‐based assays 77.7–89.7%, spike/S1‐based assay 94.3%; Nigeria: NCP‐based assays 39.3–82.7%, spike/S1‐based assay 90.7%). 15 of 600 African sera were concordantly classified as positive in both the NCP‐based and the spike/S1‐based Euroimmun ELISA, but did not inhibit spike/ACE2 binding in a surrogate virus neutralisation test. IgG antibodies elicited by previous infections with common cold CoVs were found in all sample panels, including those from Madagascar, Colombia, and Germany and thus do not inevitably hamper assay specificity. Nevertheless, high levels of IgG antibodies interacting with OC43 NCP were found in all 15 SARS‐CoV‐2 NCP/spike/S1 ELISA positive sera.
Conclusions
Depending on the chosen antigen and assay protocol, SARS‐CoV‐2 IgG ELISA specificity may be significantly reduced in certain populations probably due to interference of immune responses to endemic pathogens like other viruses or parasites.
KW - SARS‐CoV‐2
KW - seroepidemiologic studies
KW - immunoglobulin G
KW - Enzyme‐Linked Immunosorbent Assay
KW - specificity
KW - Africa
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239899
VL - 26
IS - 6
SP - 621
EP - 631
ER -
TY - JOUR
A1 - Habenstein, Jens
A1 - Schmitt, Franziska
A1 - Liessem, Sander
A1 - Ly, Alice
A1 - Trede, Dennis
A1 - Wegener, Christian
A1 - Predel, Reinhard
A1 - Rössler, Wolfgang
A1 - Neupert, Susanne
T1 - Transcriptomic, peptidomic, and mass spectrometry imaging analysis of the brain in the ant Cataglyphis nodus
JF - Journal of Neurochemistry
N2 - Behavioral flexibility is an important cornerstone for the ecological success of animals. Social Cataglyphis nodus ants with their age‐related polyethism characterized by age‐related behavioral phenotypes represent a prime example for behavioral flexibility. We propose neuropeptides as powerful candidates for the flexible modulation of age‐related behavioral transitions in individual ants. As the neuropeptidome of C. nodus was unknown, we collected a comprehensive peptidomic data set obtained by transcriptome analysis of the ants’ central nervous system combined with brain extract analysis by Q‐Exactive Orbitrap mass spectrometry (MS) and direct tissue profiling of different regions of the brain by matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) MS. In total, we identified 71 peptides with likely bioactive function, encoded on 49 neuropeptide‐, neuropeptide‐like, and protein hormone prepropeptide genes, including a novel neuropeptide‐like gene (fliktin). We next characterized the spatial distribution of a subset of peptides encoded on 16 precursor proteins with high resolution by MALDI MS imaging (MALDI MSI) on 14 µm brain sections. The accuracy of our MSI data were confirmed by matching the immunostaining patterns for tachykinins with MSI ion images from consecutive brain sections. Our data provide a solid framework for future research into spatially resolved qualitative and quantitative peptidomic changes associated with stage‐specific behavioral transitions and the functional role of neuropeptides in Cataglyphis ants.
KW - brain
KW - MALDI imaging
KW - neuropeptides
KW - neuropeptidomics
KW - social insect
KW - transcriptomics
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239917
VL - 158
IS - 2
SP - 391
EP - 412
ER -
TY - JOUR
A1 - Postema, Merel C.
A1 - Hoogman, Martine
A1 - Ambrosino, Sara
A1 - Asherson, Philip
A1 - Banaschewski, Tobias
A1 - Bandeira, Cibele E.
A1 - Baranov, Alexandr
A1 - Bau, Claiton H.D.
A1 - Baumeister, Sarah
A1 - Baur‐Streubel, Ramona
A1 - Bellgrove, Mark A.
A1 - Biederman, Joseph
A1 - Bralten, Janita
A1 - Brandeis, Daniel
A1 - Brem, Silvia
A1 - Buitelaar, Jan K.
A1 - Busatto, Geraldo F.
A1 - Castellanos, Francisco X.
A1 - Cercignani, Mara
A1 - Chaim‐Avancini, Tiffany M.
A1 - Chantiluke, Kaylita C.
A1 - Christakou, Anastasia
A1 - Coghill, David
A1 - Conzelmann, Annette
A1 - Cubillo, Ana I.
A1 - Cupertino, Renata B.
A1 - de Zeeuw, Patrick
A1 - Doyle, Alysa E.
A1 - Durston, Sarah
A1 - Earl, Eric A.
A1 - Epstein, Jeffery N.
A1 - Ethofer, Thomas
A1 - Fair, Damien A.
A1 - Fallgatter, Andreas J.
A1 - Faraone, Stephen V.
A1 - Frodl, Thomas
A1 - Gabel, Matt C.
A1 - Gogberashvili, Tinatin
A1 - Grevet, Eugenio H.
A1 - Haavik, Jan
A1 - Harrison, Neil A.
A1 - Hartman, Catharina A.
A1 - Heslenfeld, Dirk J.
A1 - Hoekstra, Pieter J.
A1 - Hohmann, Sarah
A1 - Høvik, Marie F.
A1 - Jernigan, Terry L.
A1 - Kardatzki, Bernd
A1 - Karkashadze, Georgii
A1 - Kelly, Clare
A1 - Kohls, Gregor
A1 - Konrad, Kerstin
A1 - Kuntsi, Jonna
A1 - Lazaro, Luisa
A1 - Lera‐Miguel, Sara
A1 - Lesch, Klaus‐Peter
A1 - Louza, Mario R.
A1 - Lundervold, Astri J.
A1 - Malpas, Charles B
A1 - Mattos, Paulo
A1 - McCarthy, Hazel
A1 - Namazova‐Baranova, Leyla
A1 - Nicolau, Rosa
A1 - Nigg, Joel T.
A1 - Novotny, Stephanie E.
A1 - Oberwelland Weiss, Eileen
A1 - O'Gorman Tuura, Ruth L.
A1 - Oosterlaan, Jaap
A1 - Oranje, Bob
A1 - Paloyelis, Yannis
A1 - Pauli, Paul
A1 - Picon, Felipe A.
A1 - Plessen, Kerstin J.
A1 - Ramos‐Quiroga, J. Antoni
A1 - Reif, Andreas
A1 - Reneman, Liesbeth
A1 - Rosa, Pedro G.P.
A1 - Rubia, Katya
A1 - Schrantee, Anouk
A1 - Schweren, Lizanne J.S.
A1 - Seitz, Jochen
A1 - Shaw, Philip
A1 - Silk, Tim J.
A1 - Skokauskas, Norbert
A1 - Soliva Vila, Juan C.
A1 - Stevens, Michael C.
A1 - Sudre, Gustavo
A1 - Tamm, Leanne
A1 - Tovar‐Moll, Fernanda
A1 - van Erp, Theo G.M.
A1 - Vance, Alasdair
A1 - Vilarroya, Oscar
A1 - Vives‐Gilabert, Yolanda
A1 - von Polier, Georg G.
A1 - Walitza, Susanne
A1 - Yoncheva, Yuliya N.
A1 - Zanetti, Marcus V.
A1 - Ziegler, Georg C.
A1 - Glahn, David C.
A1 - Jahanshad, Neda
A1 - Medland, Sarah E.
A1 - Thompson, Paul M.
A1 - Fisher, Simon E.
A1 - Franke, Barbara
A1 - Francks, Clyde
T1 - Analysis of structural brain asymmetries in attention‐deficit/hyperactivity disorder in 39 datasets
JF - Journal of Child Psychology and Psychiatry
N2 - Objective
Some studies have suggested alterations of structural brain asymmetry in attention‐deficit/hyperactivity disorder (ADHD), but findings have been contradictory and based on small samples. Here, we performed the largest ever analysis of brain left‐right asymmetry in ADHD, using 39 datasets of the ENIGMA consortium.
Methods
We analyzed asymmetry of subcortical and cerebral cortical structures in up to 1,933 people with ADHD and 1,829 unaffected controls. Asymmetry Indexes (AIs) were calculated per participant for each bilaterally paired measure, and linear mixed effects modeling was applied separately in children, adolescents, adults, and the total sample, to test exhaustively for potential associations of ADHD with structural brain asymmetries.
Results
There was no evidence for altered caudate nucleus asymmetry in ADHD, in contrast to prior literature. In children, there was less rightward asymmetry of the total hemispheric surface area compared to controls (t = 2.1, p = .04). Lower rightward asymmetry of medial orbitofrontal cortex surface area in ADHD (t = 2.7, p = .01) was similar to a recent finding for autism spectrum disorder. There were also some differences in cortical thickness asymmetry across age groups. In adults with ADHD, globus pallidus asymmetry was altered compared to those without ADHD. However, all effects were small (Cohen’s d from −0.18 to 0.18) and would not survive study‐wide correction for multiple testing.
Conclusion
Prior studies of altered structural brain asymmetry in ADHD were likely underpowered to detect the small effects reported here. Altered structural asymmetry is unlikely to provide a useful biomarker for ADHD, but may provide neurobiological insights into the trait.
KW - attention‐deficit
KW - hyperactivity disorder
KW - brain asymmetry
KW - brain laterality
KW - structural MRI
KW - large‐scale data
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239968
VL - 62
IS - 10
SP - 1202
EP - 1219
ER -
TY - JOUR
A1 - Wohlwend, Michael R.
A1 - Craven, Dylan
A1 - Weigelt, Patrick
A1 - Seebens, Hanno
A1 - Winter, Marten
A1 - Kreft, Holger
A1 - Zurell, Damaris
A1 - Sarmento Cabral, Juliano
A1 - Essl, Franz
A1 - van Kleunen, Mark
A1 - Pergl, Jan
A1 - Pyšek, Petr
A1 - Knight, Tiffany M.
T1 - Anthropogenic and environmental drivers shape diversity of naturalized plants across the Pacific
JF - Diversity and Distributions
N2 - Aim
The Pacific exhibits an exceptional number of naturalized plant species, but the drivers of this high diversity and the associated compositional patterns remain largely unknown. Here, we aim to (a) improve our understanding of introduction and establishment processes and (b) evaluate whether this information is sufficient to create scientific conservation tools, such as watchlists.
Location
Islands in the Pacific Ocean, excluding larger islands such as New Zealand, Japan, the Philippines and Indonesia.
Methods
We combined information from the most up‐to‐date data sources to quantify naturalized plant species richness and turnover across island groups and investigate the effects of anthropogenic, biogeographic and climate drivers on these patterns. In total, we found 2,672 naturalized plant species across 481 islands and 50 island groups, with a total of 11,074 records.
Results
Most naturalized species were restricted to few island groups, and most island groups have a low number of naturalized species. Island groups with few naturalized species were characterized by a set of widespread naturalized species. Several plant families that contributed many naturalized species globally also did so in the Pacific, particularly Fabaceae and Poaceae. However, many families were significantly over‐ or under‐represented in the Pacific naturalized flora compared to other regions of the world. Naturalized species richness increased primarily with increased human activity and island altitude/area, whereas similarity between island groups in temperature along with richness differences was most important for beta diversity.
Main conclusions
The distribution and richness of naturalized species can be explained by a small set of drivers. The Pacific region contains many naturalized plant species also naturalized in other regions in the world, but our results highlight key differences such as a stronger role of anthropogenic drivers in shaping diversity patterns. Our results establish a basis for predicting and preventing future naturalizations in a threatened biodiversity hotspot.
KW - anthropogenic drivers
KW - beta diversity
KW - island biogeography
KW - naturalized species
KW - Pacific Ocean
KW - plant invasion
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239925
VL - 27
IS - 6
SP - 1120
EP - 1133
ER -
TY - JOUR
A1 - Wabbels, Bettina
A1 - Fricke, Julia
A1 - Schittkowski, Michael
A1 - Gräf, Michael
A1 - Lorenz, Birgit
A1 - Bau, Viktoria
A1 - Nentwich, Martin M.
A1 - Atili, Abed
A1 - Eckstein, Anja
A1 - Sturm, Veit
A1 - Beisse, Christina
A1 - Sterker, Ina
A1 - Neppert, Birte
A1 - Mauschitz, Matthias M.
T1 - Yokoyama procedure for esotropia associated with high myopia: real‐world data from a large‐scale multicentre analysis
JF - Acta Ophthalmologica
N2 - Purpose
High myopic patients may develop strabismus due to globe dislocation out of the normal extraocular muscle cone. Surgical correction of this strabismus type is possible by joining the superior and lateral rectus muscles without the need for a scleral suture called the Yokoyama procedure. Data from large patient samples and the evaluation of a potential effect of an additional medial rectus recession (MRR) have been lacking so far.
Methods
We pooled retrospective patient data of 14 departments of ophthalmology in Germany and Switzerland and analysed determinants of postoperative results using multivariable regression models.
Results
We included 133 patients (mean age: 59.7 ± 13.4 years, surgery between 2008 and 2017) with a mean preoperative esotropia (both Yokoyama with and without MRR) of 23.8°±4.6°. The angle of preoperative esotropia increased with age. The postoperative esotropia was 8.7° ± 9.9°, and six patients were overcorrected. While preoperative esotropia was highly associated with postoperative results, we found no association of additional MRR with any of our postoperative outcome measures. The Yokoyama procedure had a higher absolute effect in patients with higher preoperative esotropia.
Conclusion
Our study confirms the positive effect of the Yokoyama procedure on strabismus due to high myopia in large‐scale real‐world data. In some cases, MRR may be needed because of muscle contracture, although additional MRR statistically did not affect the postoperative outcome. In patients with bilateral high myopic strabismus, correction of both eyes seems beneficial. The effect size of the Yokoyama procedure appears to be mainly driven by preoperative esotropia.
KW - esohypotropia
KW - heavy eye
KW - high myopia
KW - muscle dislocation
KW - strabismus fixus
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239939
VL - 99
IS - 8
SP - e1340
EP - e1347
ER -
TY - JOUR
A1 - Sponsler, Douglas B.
A1 - Bratman, Eve Z.
T1 - Beekeeping in, of or for the city? A socioecological perspective on urban apiculture
JF - People and Nature
N2 - The term ‘urban beekeeping’ connotes a host of meanings—sociopolitical, commercial, ecological and personal—beyond the mere description of where bees and beekeepers happen to coincide. Yet, these meanings are seldom articulated explicitly or brought into critical engagement with the relevant fields of urban ecology and political ecology.
Beginning with a brief account of the history of urban beekeeping in the United States, we draw upon urban ecological theory to construct a conceptual model of urban beekeeping that distinguishes beekeeping in, of and for the city. In our model, beekeeping in the city describes the mere importation of the traditionally rural practice of beekeeping into urban spaces for the private reasons of the individual beekeeper, whereas beekeeping of the city describes beekeeping that is consciously tailored to the urban context, often accompanied by (semi)professionalization of beekeepers and the formation of local expert communities (i.e. beekeeping associations). Beekeeping for the city describes a shift in mindset in which beekeeping is directed to civic ends beyond the boundaries of the beekeeping community per se.
Using this framework, we identify and discuss specific socioecological assets and liabilities of urban beekeeping, and how these relate to beekeeping in, of and for the city. We then formulate actionable guidelines for maturing the practice of urban beekeeping into a beneficent and self‐critical form of urban ecological citizenship; these include fostering self‐regulation within the beekeeping community, harnessing beekeeping as a ‘gateway’ experience for a broader rapprochement between urban residents and nature, and recognizing the political‐ecological context of beekeeping with respect to matters of socioecological justice.
KW - environmental justice
KW - honey bee
KW - multispecies studies
KW - policy
KW - pollinator
KW - urban greening
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239949
VL - 3
IS - 3
SP - 550
EP - 559
ER -
TY - JOUR
A1 - Schuch, Luise A.
A1 - Forstner, Maria
A1 - Rapp, Christina K.
A1 - Li, Yang
A1 - Smith, Desiree E. C.
A1 - Mendes, Marisa I.
A1 - Delhommel, Florent
A1 - Sattler, Michael
A1 - Emiralioğlu, Nagehan
A1 - Taskiran, Ekim Z.
A1 - Orhan, Diclehan
A1 - Kiper, Nural
A1 - Rohlfs, Meino
A1 - Jeske, Tim
A1 - Hastreiter, Maximilian
A1 - Gerstlauer, Michael
A1 - Torrent‐Vernetta, Alba
A1 - Moreno‐Galdó, Antonio
A1 - Kammer, Birgit
A1 - Brasch, Frank
A1 - Reu‐Hofer, Simone
A1 - Griese, Matthias
T1 - FARS1‐related disorders caused by bi‐allelic mutations in cytosolic phenylalanyl‐tRNA synthetase genes: Look beyond the lungs!
JF - Clinical Genetics
N2 - Aminoacyl‐tRNA synthetases (ARSs) catalyze the first step of protein biosynthesis (canonical function) and have additional (non‐canonical) functions outside of translation. Bi‐allelic pathogenic variants in genes encoding ARSs are associated with various recessive mitochondrial and multisystem disorders. We describe here a multisystem clinical phenotype based on bi‐allelic mutations in the two genes (FARSA, FARSB) encoding distinct subunits for tetrameric cytosolic phenylalanyl‐tRNA synthetase (FARS1). Interstitial lung disease with cholesterol pneumonitis on histology emerged as an early characteristic feature and significantly determined disease burden. Additional clinical characteristics of the patients included neurological findings, liver dysfunction, and connective tissue, muscular and vascular abnormalities. Structural modeling of newly identified missense mutations in the alpha subunit of FARS1, FARSA, showed exclusive mapping to the enzyme's conserved catalytic domain. Patient‐derived mutant cells displayed compromised aminoacylation activity in two cases, while remaining unaffected in another. Collectively, these findings expand current knowledge about the human ARS disease spectrum and support a loss of canonical and non‐canonical function in FARS1‐associated recessive disease.
KW - aminoacyl‐tRNA synthetases
KW - cholesterol pneumonitis
KW - FARS1
KW - children´s interstitial lung disease (chILD) lipoid pneumonia
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238827
VL - 99
IS - 6
SP - 789
EP - 801
ER -
TY - JOUR
A1 - Opitz, Timm
A1 - Schuwerk, Tobias
A1 - Paulus, Markus
A1 - Kloo, Daniela
A1 - Osterhaus, Christopher
A1 - Lesch, Klaus‐Peter
A1 - Sodian, Beate
T1 - No links between genetic variation and developing theory of mind: A preregistered replication attempt of candidate gene studies
JF - Developmental Science
N2 - Genetic variability is being discussed as a source of inter‐individual differences in Theory of Mind development. Previous studies documented an association between variations in DRD4 VNTR 48 bp, OXTR rs53576, COMT rs4680, and Theory of Mind task performance. As empirical evidence on these associations is sparse, we conducted a preregistered replication attempt of a study reporting a link between DRD4 VNTR 48 bp and false belief understanding in 50‐month‐old children [Lackner, C., Sabbagh, M. A., Hallinan, E., Liu, X., & Holden, J. J. (2012). Developmental Science, 15(2), 272–280.]. Additionally, we attempted a replication of studies on the role of OXTR rs53576 and COMT rs4680 in Theory of Mind. In both replication attempts, we did not find any evidence for associations between the sampled genetic markers and Theory of Mind ability in a series of analyses. Extending the replication attempt of Lackner et al., we employed longitudinal data from several tasks and measurement points, which allowed us to run follow‐up robustness checks with more reliable scores. These extensive analyses corroborated our null finding. This comprehensive non‐replication is important to balance current research on genetic markers of Theory of Mind. In a combined evaluation of our own and previous studies, we point to substantial methodological issues that research on the genetic basis of Theory of Mind development faces. We conclude that these limitations currently prevent firm conclusions on genetic influences on Theory of Mind development.
KW - COMT
KW - DRD4
KW - false belief
KW - OXTR
KW - theory of mind
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238812
VL - 24
IS - 5
ER -
TY - JOUR
A1 - Mayr, Antonia V.
A1 - Keller, Alexander
A1 - Peters, Marcell K.
A1 - Grimmer, Gudrun
A1 - Krischke, Beate
A1 - Geyer, Mareen
A1 - Schmitt, Thomas
A1 - Steffan‐Dewenter, Ingolf
T1 - Cryptic species and hidden ecological interactions of halictine bees along an elevational gradient
JF - Ecology and Evolution
N2 - Changes of abiotic and biotic conditions along elevational gradients represent serious challenges to organisms which may promote the turnover of species, traits and biotic interaction partners. Here, we used molecular methods to study cuticular hydrocarbon (CHC) profiles, biotic interactions and phylogenetic relationships of halictid bees of the genus Lasioglossum along a 2,900 m elevational gradient at Mt. Kilimanjaro, Tanzania. We detected a strong species turnover of morphologically indistinguishable taxa with phylogenetically clustered cryptic species at high elevations, changes in CHC profiles, pollen resource diversity, and a turnover in the gut and body surface microbiome of bees. At high elevations, increased proportions of saturated compounds in CHC profiles indicate physiological adaptations to prevent desiccation. More specialized diets with higher proportions of low‐quality Asteraceae pollen imply constraints in the availability of food resources. Interactive effects of climatic conditions on gut and surface microbiomes, CHC profiles, and pollen diet suggest complex feedbacks among abiotic conditions, ecological interactions, physiological adaptations, and phylogenetic constraints as drivers of halictid bee communities at Mt. Kilimanjaro.
KW - COI
KW - cuticular chemistry
KW - elevational gradient
KW - Halictidae
KW - microbiome metabarcoding
KW - pollen metabarcoding
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238853
VL - 11
IS - 12
SP - 7700
EP - 7712
ER -
TY - JOUR
A1 - Piselli, Claudio
A1 - Benz, Roland
T1 - Fosmidomycin transport through the phosphate‐specific porins OprO and OprP of Pseudomonas aeruginosa
JF - Molecular Microbiology
N2 - The Gram‐negative bacterium Pseudomonas aeruginosa is an opportunistic pathogen, responsible for many hospital‐acquired infections. The bacterium is quite resistant toward many antibiotics, in particular because of the fine‐tuned permeability of its outer membrane (OM). General diffusion outer membrane pores are quite rare in this organism. Instead, its OM contains many substrate‐specific porins. Their expression is varying according to growth conditions and virulence. Phosphate limitations, as well as pathogenicity factors, result in the induction of the two mono‐ and polyphosphate‐specific porins, OprP and OprO, respectively, together with an inner membrane uptake mechanism and a periplasmic binding protein. These outer membrane channels could serve as outer membrane pathways for the uptake of phosphonates. Among them are not only herbicides, but also potent antibiotics, such as fosfomycin and fosmidomycin. In this study, we investigated the interaction between OprP and OprO and fosmidomycin in detail. We could demonstrate that fosmidomycin is able to bind to the phosphate‐specific binding site inside the two porins. The inhibition of chloride conductance of OprP and OprO by fosmidomycin is considerably less than that of phosphate or diphosphate, but it can be measured in titration experiments of chloride conductance and also in single‐channel experiments. The results suggest that fosmidomycin transport across the OM of P. aeruginosa occurs through OprP and OprO. Our data with the ones already known in the literature show that phosphonic acid‐containing antibiotics are in general good candidates to treat the infections of P. aeruginosa at the very beginning through a favorable OM transport system.
KW - fosmidomycin
KW - lipid bilayer membrane
KW - OprO
KW - OprP
KW - porin
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238905
VL - 116
IS - 1
SP - 97
EP - 108
ER -
TY - JOUR
A1 - Vogel, Sebastian
A1 - Prinzing, Andreas
A1 - Bußler, Heinz
A1 - Müller, Jörg
A1 - Schmidt, Stefan
A1 - Thorn, Simon
T1 - Abundance, not diversity, of host beetle communities determines abundance and diversity of parasitoids in deadwood
JF - Ecology and Evolution
N2 - Most parasites and parasitoids are adapted to overcome defense mechanisms of their specific hosts and hence colonize a narrow range of host species. Accordingly, an increase in host functional or phylogenetic dissimilarity is expected to increase the species diversity of parasitoids. However, the local diversity of parasitoids may be driven by the accessibility and detectability of hosts, both increasing with increasing host abundance. Yet, the relative importance of these two mechanisms remains unclear. We parallelly reared communities of saproxylic beetle as potential hosts and associated parasitoid Hymenoptera from experimentally felled trees. The dissimilarity of beetle communities was inferred from distances in seven functional traits and from their evolutionary ancestry. We tested the effect of host abundance, species richness, functional, and phylogenetic dissimilarities on the abundance, species richness, and Shannon diversity of parasitoids. Our results showed an increase of abundance, species richness, and Shannon diversity of parasitoids with increasing beetle abundance. Additionally, abundance of parasitoids increased with increasing species richness of beetles. However, functional and phylogenetic dissimilarity showed no effect on the diversity of parasitoids. Our results suggest that the local diversity of parasitoids, of ephemeral and hidden resources like saproxylic beetles, is highest when resources are abundant and thereby detectable and accessible. Hence, in some cases, resources do not need to be diverse to promote parasitoid diversity.
KW - barcoding
KW - deadwood
KW - experiment
KW - host–parasitoid interaction
KW - natural enemy
KW - specialization
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238892
VL - 11
IS - 11
SP - 6881
EP - 6888
ER -
TY - JOUR
A1 - Leidinger, Ludwig
A1 - Vedder, Daniel
A1 - Cabral, Juliano Sarmento
T1 - Temporal environmental variation may impose differential selection on both genomic and ecological traits
JF - Oikos
N2 - The response of populations and species to changing conditions determines how community composition will change functionally, including via trait shifts. Selection from standing variation has been suggested to be more efficient than acquiring new mutations. Yet, studies on community trait composition and trait selection largely focus on phenotypic variation in ecological traits, whereas the underlying genomic traits remain understudied. Using a genome‐explicit, niche‐ and individual‐based model, we address the potential interactions between genomic and ecological traits shaping communities under an environmental selective forcing, namely temporal positively autocorrelated environmental fluctuation. In this model, all ecological traits are explicitly coded by the genome. For our experiments, we initialized 90 replicate communities, each with ca 350 initial species, characterized by random genomic and ecological trait combinations, on a 2D spatially explicit landscape with two orthogonal gradients (temperature and resource use). We exposed each community to two contrasting scenarios: without (i.e. static environments) and with temporal variation. We then analyzed emerging compositions of both genomic and ecological traits at the community, population and genomic levels. Communities in variable environments were species poorer than in static environments, and populations more abundant, whereas genomes had lower genetic linkage, mean genetic variation and a non‐significant tendency towards higher numbers of genes. The surviving genomes (i.e. those selected by variable environments) coded for enhanced environmental tolerance and smaller biomass, which resulted in faster life cycles and thus also in increased potential for evolutionary rescue. Under temporal environmental variation, larger, less linked genomes retained more variation in mean dispersal ability at the population level than at genomic level, whereas the opposite trend emerged for biomass. Our results provide clues to how sexually‐reproducing diploid plant communities might react to variable environments and highlights the importance of genomic traits and their interaction with ecological traits for eco‐evolutionary responses to changing climates.
KW - environmental variability
KW - genomic traits
KW - mechanistic model
KW - rapid evolution
KW - standing variation
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238945
VL - 130
IS - 7
SP - 1100
EP - 1115
ER -
TY - JOUR
A1 - Hoesl, Christine
A1 - Fröhlich, Thomas
A1 - Posch, Christian
A1 - Kneitz, Hermann
A1 - Goebeler, Matthias
A1 - Schneider, Marlon R.
A1 - Dahlhoff, Maik
T1 - The transmembrane protein LRIG1 triggers melanocytic tumor development following chemically induced skin carcinogenesis
JF - Molecular Oncology
N2 - The incidence of melanoma and nonmelanoma skin cancer has increased tremendously in recent years. Although novel treatment options have significantly improved patient outcomes, the prognosis for most patients with an advanced disease remains dismal. It is, thus, imperative to understand the molecular mechanisms involved in skin carcinogenesis in order to develop new targeted treatment strategies. Receptor tyrosine kinases (RTK) like the ERBB receptor family, including EGFR/ERBB1, ERBB2/NEU, ERBB3, and ERBB4, are important regulators of skin homeostasis and their dysregulation often results in cancer, which makes them attractive therapeutic targets. Members of the leucine‐rich repeats and immunoglobulin‐like domains protein family (LRIG1‐3) are ERBB regulators and thus potential therapeutic targets to manipulate ERBB receptors. Here, we analyzed the function of LRIG1 during chemically induced skin carcinogenesis in transgenic mice expressing LRIG1 in the skin under the control of the keratin 5 promoter (LRIG1‐TG mice). We observed a significant induction of melanocytic tumor formation in LRIG1‐TG mice and no difference in papilloma incidence between LRIG1‐TG and control mice. Our findings also revealed that LRIG1 affects ERBB signaling via decreased phosphorylation of EGFR and increased activation of the oncoprotein ERBB2 during skin carcinogenesis. The epidermal proliferation rate was significantly decreased during epidermal tumorigenesis under LRIG1 overexpression, and the apoptosis marker cleaved caspase 3 was significantly activated in the epidermis of transgenic LRIG1 mice. Additionally, we detected LRIG1 expression in human cutaneous squamous cell carcinoma and melanoma samples. Therefore, we depleted LRIG1 in human melanoma cells (A375) by CRISPR/Cas9 technology and found that this caused EGFR and ERBB3 downregulation in A375 LRIG1 knockout cells 6 h following stimulation with EGF. In conclusion, our study demonstrated that LRIG1‐TG mice develop melanocytic skin tumors during chemical skin carcinogenesis and a deletion of LRIG1 in human melanoma cells reduces EGFR and ERBB3 expression after EGF stimulation.
KW - ERBB receptors
KW - LRIG1
KW - melanoma
KW - mouse model
KW - skin carcinogenesis
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238925
VL - 15
IS - 8
SP - 2140
EP - 2155
ER -
TY - JOUR
A1 - Emmert, Adrian
A1 - Kneisel, Christof
T1 - Internal structure and palsa development at Orravatnsrústir Palsa Site (Central Iceland), investigated by means of integrated resistivity and ground‐penetrating radar methods
JF - Permafrost and Periglacial Processes
N2 - The natural cyclical development of palsas makes it difficult to use visible signs of decay as reference points for environmental change. Thus, to determine the actual development stage of a palsa, investigations of the internal structure are crucial. Our study presents 2‐D and 3‐D electrical resistivity imaging (ERI) and 2‐D ground‐penetrating radar (GPR) results, measurements of surface and subsurface temperatures, and of the soil matric potential from Orravatnsrústir Palsa Site in Central Iceland. By a joint interpretation of the results, we deduce the internal structure (i.e., thickness of thaw zone and permafrost, ice/water content) of five palsas of different size and shape. The results differentiate between initial and mature development stages and show that palsas of different development stages can exist in close proximity. While internal characteristics indicate undisturbed development of four palsas, one palsa shows indications of environmental change. Our study shows the value of the multimethod geophysical approach and introduces measurements of the soil matric potential as a promising method to assess the current state of the subsurface.
KW - 3‐D electrical resistivity imaging
KW - ground‐penetrating radar
KW - palsa development
KW - soil matric potential
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238933
VL - 32
IS - 3
SP - 503
EP - 519
ER -
TY - JOUR
A1 - Müller, Diana
A1 - Bessi, Irene
A1 - Richter, Christian
A1 - Schwalbe, Harald
T1 - The Folding Landscapes of Human Telomeric RNA and DNA G‐Quadruplexes are Markedly Different
JF - Angewandte Chemie International Edition
N2 - We investigated the folding kinetics of G‐quadruplex (G4) structures by comparing the K\(^{+}\)‐induced folding of an RNA G4 derived from the human telomeric repeat‐containing RNA (TERRA25) with a sequence homologous DNA G4 (wtTel25) using CD spectroscopy and real‐time NMR spectroscopy. While DNA G4 folding is biphasic, reveals kinetic partitioning and involves kinetically favoured off‐pathway intermediates, RNA G4 folding is faster and monophasic. The differences in kinetics are correlated to the differences in the folded conformations of RNA vs. DNA G4s, in particular with regard to the conformation around the glycosidic torsion angle χ that uniformly adopts anti conformations for RNA G4s and both, syn and anti conformation for DNA G4s. Modified DNA G4s with \(^{19}\)F bound to C2′ in arabino configuration adopt exclusively anti conformations for χ. These fluoro‐modified DNA (antiTel25) reveal faster folding kinetics and monomorphic conformations similar to RNA G4s, suggesting the correlation between folding kinetics and pathways with differences in χ angle preferences in DNA and RNA, respectively.
KW - folding landscapes
KW - G-quadruplexes
KW - kinetics
KW - real-time NMR spectroscopy
KW - TERRA RNA
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238917
VL - 60
IS - 19
SP - 10895
EP - 10901
ER -
TY - JOUR
A1 - Hoche, Joscha
A1 - Flock, Marco
A1 - Miao, Xincheng
A1 - Philipp, Luca Nils
A1 - Wenzel, Michael
A1 - Fischer, Ingo
A1 - Mitric, Roland
T1 - Excimer formation dynamics in the isolated tetracene dimer
JF - Chemical Science
N2 - The understanding of excimer formation and its interplay with the singlet-correlated triplet pair state \(^{1}\)(TT) is of high significance for the development of efficient organic electronics. Here, we study the photoinduced dynamics of the tetracene dimer in the gas phase by time-resolved photoionisation and photoion imaging experiments as well as nonadiabatic dynamics simulations in order to obtain mechanistic insight into the excimer formation dynamics. The experiments are performed using a picosecond laser system for excitation into the S\(_{2}\) state and reveal a biexponential time dependence. The time constants, obtained as a function of excess energy, lie in the range between ≈10 ps and 100 ps and are assigned to the relaxation of the excimer on the S\(_{1}\) surface and to its deactivation to the ground state. Simulations of the quantum-classical photodynamics are carried out in the frame of the semi-empirical CISD and TD-lc-DFTB methods. Both theoretical approaches reveal a dominating relaxation pathway that is characterised by the formation of a perfectly stacked excimer. TD-lc-DFTB simulations have also uncovered a second relaxation channel into a less stable dimer conformation in the S\(_{1}\) state. Both methods have consistently shown that the electronic and geometric relaxation to the excimer state is completed in less than 10 ps. The inclusion of doubly excited states in the CISD dynamics and their diabatisation further allowed to observe a transient population of the \(^{1}\)(TT) state, which, however, gets depopulated on a timescale of 8 ps, leading finally to the trapping in the excimer minimum.
KW - excimer formation
KW - tetracene dimer
KW - organic electronics
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-251559
VL - 12
IS - 36
SP - 11965
EP - 11975
ER -
TY - JOUR
A1 - Maier, Jan
A1 - Marder, Todd B.
T1 - Mechanistic and Kinetic Factors of ortho‐Benzyne Formation in Hexadehydro‐Diels‐Alder (HDDA) Reactions
JF - Chemistry – A European Journal
N2 - With the rapid development of the hexadehydro‐Diels‐Alder reaction (HDDA) from its first discovery in 1997, the question of whether a concerted or stepwise mechanism better describes the thermally activated formation of ortho‐benzyne from a diyne and a diynophile has been debated. Mechanistic and kinetic investigations were able to show that this is not a black or white situation, as minor changes can tip the balance. For that reason, especially, linked yne‐diynes were studied to examine steric, electronic, and radical‐stabilizing effects of their terminal substituents on the reaction mechanism and kinetics. Furthermore, the influence of the nature of the linker on the HDDA reaction was explored. The more recently discovered photochemical HDDA reaction also gives ortho‐arynes, which display the same reactivity as the thermally generated ones, but their formation might not proceed by the same mechanism. This minireview summarizes the current state of mechanistic understanding of the HDDA reaction.
KW - Alkyne
KW - Benzyne
KW - Cyclization
KW - Hexadehydro-Diels-Alder
KW - reaction mechanism
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239006
VL - 27
IS - 30
SP - 7978
EP - 7991
ER -
TY - JOUR
A1 - Berger, Sarina M.
A1 - Ferger, Matthias
A1 - Marder, Todd B.
T1 - Synthetic Approaches to Triarylboranes from 1885 to 2020
JF - Chemistry – A European Journal
N2 - In recent years, research in the fields of optoelectronics, anion sensors and bioimaging agents have been greatly influenced by novel compounds containing triarylborane motifs. Such compounds possess an empty p‐orbital at boron which results in useful optical and electronic properties. Such a diversity of applications was not expected when the first triarylborane was reported in 1885. Synthetic approaches to triarylboranes underwent various changes over the following century, some of which are still used in the present day, such as the generally applicable routes developed by Krause et al. in 1922, or by Grisdale et al. in 1972 at Eastman Kodak. Some other developments were not pursued further after their initial reports, such as the synthesis of two triarylboranes bearing three different aromatic groups by Mikhailov et al. in 1958. This review summarizes the development of synthetic approaches to triarylboranes from their first report nearly 135 years ago to the present.
KW - arylmetalate
KW - boranes
KW - chromophore
KW - Lewis acid
KW - synthetic methods
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238952
VL - 27
IS - 24
SP - 7043
EP - 7058
ER -
TY - JOUR
A1 - Krüger, Sören
A1 - Leskien, Miriam
A1 - Schuller, Patricia
A1 - Prifert, Christiane
A1 - Weißbrich, Benedikt
A1 - Vogel, Ulrich
A1 - Krone, Manuel
T1 - Performance and feasibility of universal PCR admission screening for SARS‐CoV‐2 in a German tertiary care hospital
JF - Journal of Medical Virology
N2 - Anamnestic screening of symptoms and contact history is applied to identify coronavirus disease 2019 (COVID‐19) patients on admission. However, asymptomatic and presymptomatic patients remain undetected although the viral load may be high. In this retrospective cohort study, all hospitalized patients who received polymerase chain reaction (PCR) admission testing from March 26th until May 24th, 2020 were included. Data on COVID‐19‐specific symptoms and contact history to COVID‐19 cases were retrospectively extracted from patient files and from contact tracing notes. The compliance to the universal testing protocol was high with 90%. Out of 6940 tested patients, 27 new severe acute respiratory syndrome coronavirus‐2 infections (0.4%) were detected. Seven of those COVID‐19 cases (26% of all new cases) were asymptomatic and had no positive contact history, but were identified through a positive PCR test. The number needed to identify an asymptomatic patient was 425 in the first wave of the epidemic, 1218 in the low incidence phase. The specificity of the method was above 99.9%. Universal PCR testing was highly accepted by staff as demonstrated by high compliance. The costs to detect one asymptomatic case in future studies need to be traded off against the costs and damage caused by potential outbreaks of COVID‐19.
KW - admission screening
KW - COVID‐19
KW - infection control
KW - SARS‐CoV‐2
KW - testing strategy
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238971
VL - 93
IS - 5
SP - 2890
EP - 2898
ER -
TY - JOUR
A1 - Crumbach, Merian
A1 - Bachmann, Jonas
A1 - Fritze, Lars
A1 - Helbig, Andreas
A1 - Krummenacher, Ivo
A1 - Braunschweig, Holger
A1 - Helten, Holger
T1 - Dithiophene‐Fused Oxadiborepins and Azadiborepins: A New Class of Highly Fluorescent Heteroaromatics
JF - Angewandte Chemie International Edition
N2 - Access to dithiophene‐fused oxadiborepins and the first azadiborepins attained via a modular synthesis route are presented. The new compounds emit intense blue light, some of which demonstrate fluorescence quantum yields close to unity. Cyclic voltammetry (CV) revealed electrochemically reversible one‐electron reduction processes. The weak aromatic character of the novel 1,2,7‐azadiborepin ring is demonstrated with in‐depth theoretical investigations using nucleus‐independent chemical shift (NICS) scans and anisotropy of the induced current density (ACID) calculations.
KW - aromaticity
KW - BN compounds
KW - boron
KW - isoelectronic analogues
KW - polycycles
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238996
VL - 60
IS - 17
SP - 9290
EP - 9295
ER -
TY - JOUR
A1 - Hofmann, Julian
A1 - Ginex, Tiziana
A1 - Espargaró, Alba
A1 - Scheiner, Matthias
A1 - Gunesch, Sandra
A1 - Aragó, Marc
A1 - Stigloher, Christian
A1 - Sabaté, Raimon
A1 - Luque, F. Javier
A1 - Decker, Michael
T1 - Azobioisosteres of Curcumin with Pronounced Activity against Amyloid Aggregation, Intracellular Oxidative Stress, and Neuroinflammation
JF - Chemistry – A European Journal
N2 - Many (poly‐)phenolic natural products, for example, curcumin and taxifolin, have been studied for their activity against specific hallmarks of neurodegeneration, such as amyloid‐β 42 (Aβ42) aggregation and neuroinflammation. Due to their drawbacks, arising from poor pharmacokinetics, rapid metabolism, and even instability in aqueous medium, the biological activity of azobenzene compounds carrying a pharmacophoric catechol group, which have been designed as bioisoteres of curcumin has been examined. Molecular simulations reveal the ability of these compounds to form a hydrophobic cluster with Aβ42, which adopts different folds, affecting the propensity to populate fibril‐like conformations. Furthermore, the curcumin bioisosteres exceeded the parent compound in activity against Aβ42 aggregation inhibition, glutamate‐induced intracellular oxidative stress in HT22 cells, and neuroinflammation in microglial BV‐2 cells. The most active compound prevented apoptosis of HT22 cells at a concentration of 2.5 μm (83 % cell survival), whereas curcumin only showed very low protection at 10 μm (21 % cell survival).
KW - amyloid beta
KW - bioisosterism
KW - natural products
KW - neuroprotectivity
KW - replica-exchange molecular dynamics
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238988
VL - 27
IS - 19
SP - 6015
EP - 6027
ER -
TY - JOUR
A1 - Haack, Stephanie
A1 - Baiker, Sarah
A1 - Schlegel, Jan
A1 - Sauer, Markus
A1 - Sparwasser, Tim
A1 - Langenhorst, Daniela
A1 - Beyersdorf, Niklas
T1 - Superagonistic CD28 stimulation induces IFN‐γ release from mouse T helper 1 cells in vitro and in vivo
JF - European Journal of Immunology
N2 - Like human Th1 cells, mouse Th1 cells also secrete IFN‐γ upon stimulation with a superagonistic anti‐CD28 monoclonal antibody (CD28‐SA). Crosslinking of the CD28‐SA via FcR and CD40‐CD40L interactions greatly increased IFN‐γ release. Our data stress the utility of the mouse as a model organism for immune responses in humans.
KW - CD28
KW - Th1 cells
KW - cytokine release
KW - interferon γ
KW - Superagonistic antibody
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239028
VL - 51
IS - 3
SP - 738
EP - 741
ER -
TY - JOUR
A1 - Kamali, Salar
A1 - Rajendran, Ranjithkumar
A1 - Stadelmann, Christine
A1 - Karnati, Srikanth
A1 - Rajendran, Vinothkumar
A1 - Giraldo‐Velasquez, Mario
A1 - Berghoff, Martin
T1 - Oligodendrocyte‐specific deletion of FGFR2 ameliorates MOG\(_{35-55}\)‐induced EAE through ERK and Akt signalling
JF - Brain Pathology
N2 - Fibroblast growth factors (FGFs) and their receptors (FGFRs) are involved in demyelinating pathologies including multiple sclerosis (MS). In our recent study, oligodendrocyte‐specific deletion of FGFR1 resulted in a milder disease course, less inflammation, reduced myelin and axon damage in EAE. The objective of this study was to elucidate the role of oligodendroglial FGFR2 in MOG\(_{35-55}\)‐induced EAE. Oligodendrocyte‐specific knockout of FGFR2 (Fgfr2\(^{ind-/-}\)) was achieved by application of tamoxifen; EAE was induced using the MOG\(_{35-55}\) peptide. EAE symptoms were monitored over 62 days. Spinal cord tissue was analysed by histology, immunohistochemistry and western blot. Fgfr2\(^{ind-/-}\) mice revealed a milder disease course, less myelin damage and enhanced axonal density. The number of oligodendrocytes was not affected in demyelinated areas. However, protein expression of FGFR2, FGF2 and FGF9 was downregulated in Fgfr2\(^{ind-/-}\) mice. FGF/FGFR dependent signalling proteins were differentially regulated; pAkt was upregulated and pERK was downregulated in Fgfr2\(^{ind-/-}\) mice. The number of CD3(+) T cells, Mac3(+) cells and B220(+) B cells was less in demyelinated lesions of Fgfr2\(^{ind-/-}\) mice. Furthermore, expression of IL‐1β, TNF‐α and CD200 was less in Fgfr2\(^{ind-/-}\) mice than controls. Fgfr2ind−/− mice showed an upregulation of PLP and downregulation of the remyelination inhibitors SEMA3A and TGF‐β expression. These data suggest that cell‐specific deletion of FGFR2 in oligodendrocytes has anti‐inflammatory and neuroprotective effects accompanied by changes in FGF/FGFR dependent signalling, inflammatory cytokines and expression of remyelination inhibitors. Thus, FGFRs in oligodendrocytes may represent potential targets for the treatment of inflammatory and demyelinating diseases including MS.
KW - experimental autoimmune encephalomyelitis
KW - FGF/FGFR signalling
KW - multiple sclerosis
KW - oligodendrocytes
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224354
VL - 31
SP - 297
EP - 311
ER -
TY - JOUR
A1 - Brych, Mareike
A1 - Händel, Barbara F.
A1 - Riechelmann, Eva
A1 - Pieczykolan, Aleksandra
A1 - Huestegge, Lynn
T1 - Effects of vocal demands on pupil dilation
JF - Psychophysiology
N2 - Pupil dilation is known to be affected by a variety of factors, including physical (e.g., light) and cognitive sources of influence (e.g., mental load due to working memory demands, stimulus/response competition etc.). In the present experiment, we tested the extent to which vocal demands (speaking) can affect pupil dilation. Based on corresponding preliminary evidence found in a reanalysis of an existing data set from our lab, we setup a new experiment that systematically investigated vocal response‐related effects compared to mere jaw/lip movement and button press responses. Conditions changed on a trial‐by‐trial basis while participants were instructed to keep fixating a central cross on a screen throughout. In line with our prediction (and previous observation), speaking caused the pupils to dilate strongest, followed by nonvocal movements and finally a baseline condition without any vocal or muscular demands. An additional analysis of blink rates showed no difference in blink frequency between vocal and baseline conditions, but different blink dynamics. Finally, simultaneously recorded electromyographic activity showed that muscle activity may contribute to some (but not all) aspects of the observed effects on pupil size. The results are discussed in the context of other recent research indicating effects of perceived (instead of executed) vocal action on pupil dynamics.
KW - blink rate
KW - eye movements
KW - movement interaction
KW - pupil dilation
KW - vocal responses
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224425
VL - 58
IS - 2
ER -
TY - JOUR
A1 - Granath, Tim
A1 - Löbmann, Peer
A1 - Mandel, Karl
T1 - Oxidative Precipitation as a Versatile Method to Obtain Ferromagnetic Fe\(_{3}\)O\(_{4}\) Nano‐ and Mesocrystals Adjustable in Morphology and Magnetic Properties
JF - Particle & Particle Systems Characterization
N2 - Oxidative precipitation is a facile synthesis method to obtain ferromagnetic iron oxide nanoparticles from ferrous salts—with unexplored potential. The concentration of base and oxidant alone strongly affects the particle's structure and thus their magnetic properties despite the same material, magnetite (Fe\(_{3}\)O\(_{4}\)), is obtained when precipitated with potassium hydroxide (KOH) from ferrous sulfate (FeSO\(_{4}\)) and treated with potassium nitrate (KNO\(_{3}\)) at appropriate temperature. Depending on the potassium hydroxide and potassium nitrate concentrations, it is possible to obtain a series of different types of either single crystals or mesocrystals. The time‐dependent mesocrystal evolution can be revealed via electron microscopy and provides insights into the process of oriented attachment, yielding faceted particles, showing a facet‐dependent reactivity. It is found that it is the nitrate and hydroxide concentration that influences the ligand exchange process and thus the crystallization pathways. The presence of sulfate ions contributes to the mesocrystal evolution as well, as sulfate apparently hinders further crystal fusion, as revealed via infrared spectroscopy. Finally, it is found that nitrite, as one possible and ecologically highly relevant reduction product occurring in nature in context with iron, only evolves if the reaction is quantitative.
KW - colloidal nanostructures
KW - nanoparticle aggregation
KW - non‐classical crystallization
KW - oriented attachment
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224419
VL - 38
IS - 3
ER -
TY - JOUR
A1 - Rang, Maximilian
A1 - Fantuzzi, Felipe
A1 - Arrowsmith, Merle
A1 - Krummenacher, Ivo
A1 - Beck, Eva
A1 - Witte, Robert
A1 - Matler, Alexander
A1 - Rempel, Anna
A1 - Bischof, Tobias
A1 - Radacki, Krzysztof
A1 - Engels, Bernd
A1 - Braunschweig, Holger
T1 - Reduktion und Umlagerung eines Bor(I)‐Carbonylkomplexes
JF - Angewandte Chemie
N2 - Bei der Einelektronenreduktion eines durch eine cyclisches (Alkyl)(amino)carben (CAAC) stabilisierten Arylborylen-Carbonylkomplexes erfolgt die Bildung eines dimeren Borylketyl-Radikalanions, bedingt durch eine intramolekulare Arylmigration zum CO Kohlenstoffatom. Computergestützte Analyse liefert Hinweise auf eine radikalanionische [(CAAC)B(CO)Ar]\(^{.-}\) Zwischenstufe. Weiterführende Reduktion des entstandenen Komplexes liefert ein hoch nukleophiles (Boranyliden)methanolat.
KW - Biradikale
KW - Bor-Carbonylkomplexe
KW - Dichtefunktionalrechnungen
KW - Reduktionen
KW - Umlagerungen
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224409
VL - 133
IS - 6
SP - 3000
EP - 3005
ER -
TY - JOUR
A1 - Schindler, Julia
A1 - Richter, Tobias
A1 - Mar, Raymond
T1 - Does generation benefit learning for narrative and expository texts? A direct replication attempt
JF - Applied Cognitive Psychology
N2 - Generated information is better recognized and recalled than information that is read. This so‐called generation effect has been replicated several times for different types of material, including texts. Perhaps the most influential demonstration was by McDaniel et al. (1986, Journal of Memory and Language, 25, 645–656; henceforth MEDC). This group tested whether the generation effect occurs only if the generation task stimulates cognitive processes not already stimulated by the text. Numerous studies, however, report difficulties replicating this text by generation‐task interaction, which suggests that the effect might only be found under conditions closer to the original method of MEDC. To test this assumption, we will closely replicate MEDC's Experiment 2 in German and English‐speaking samples. Replicating the effect would suggest that it can be reproduced, at least under limited conditions, which will provide the necessary foundation for future investigations into the boundary conditions of this effect, with an eye towards its utility in applied contexts.
KW - expository texts
KW - generation effect
KW - learning
KW - narrative texts
KW - replication
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224496
VL - 35
IS - 2
SP - 559
EP - 564
ER -
TY - JOUR
A1 - Miller, Franziska
A1 - Wintzheimer, Susanne
A1 - Prieschl, Johannes
A1 - Strauss, Volker
A1 - Mandel, Karl
T1 - A Supraparticle‐Based Five‐Level‐Identification Tag That Switches Information Upon Readout
JF - Advanced Optical Materials
N2 - Product identification tags are of great importance in a globalized world with increasingly complex trading routes and networks. Beyond currently used coding strategies, such as QR codes, higher data density, flexible application as well as miniaturization and readout indication are longed for in the next generation of security tags. In this work, micron‐sized supraparticles (SPs) with encoded information (ID) are produced that not only exhibit multiple initially covert identification levels but are also irreversibly marked as “read” upon readout. To achieve this, lanthanide doped CaF\(_{2}\) nanoparticles are assembled in various quantity‐weighted ratios via spray‐drying in presence of a broad‐spectrum stealth fluorophore (StFl), yielding covert spectrally encoded ID‐SPs. Using these as pigments, QR codes, initially dominated by the green fluorescence of the StFl, could be generated. Upon thermal energy input, these particle‐based tags irreversibly switch to an activated state revealing not only multiple luminescent colors but also spectral IDs. This strategy provides the next generation of material‐based security tags with a high data density and security level that switch information upon readout and can be, therefore, used as seal of quality.
KW - multilevel luminescence identification
KW - rare earth doped nanoparticles
KW - security tags
KW - stealth fluorophores
KW - supraparticles
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224469
VL - 9
IS - 4
ER -
TY - JOUR
A1 - Koeniger, Tobias
A1 - Bell, Luisa
A1 - Mifka, Anika
A1 - Enders, Michael
A1 - Hautmann, Valentin
A1 - Mekala, Subba Rao
A1 - Kirchner, Philipp
A1 - Ekici, Arif B.
A1 - Schulz, Christian
A1 - Wörsdörfer, Philipp
A1 - Mencl, Stine
A1 - Kleinschnitz, Christoph
A1 - Ergün, Süleyman
A1 - Kuerten, Stefanie
T1 - Bone marrow‐derived myeloid progenitors in the leptomeninges of adult mice
JF - Stem Cells
N2 - Although the bone marrow contains most hematopoietic activity during adulthood, hematopoietic stem and progenitor cells can be recovered from various extramedullary sites. Cells with hematopoietic progenitor properties have even been reported in the adult brain under steady‐state conditions, but their nature and localization remain insufficiently defined. Here, we describe a heterogeneous population of myeloid progenitors in the leptomeninges of adult C57BL/6 mice. This cell pool included common myeloid, granulocyte/macrophage, and megakaryocyte/erythrocyte progenitors. Accordingly, it gave rise to all major myelo‐erythroid lineages in clonogenic culture assays. Brain‐associated progenitors persisted after tissue perfusion and were partially inaccessible to intravenous antibodies, suggesting their localization behind continuous blood vessel endothelium such as the blood‐arachnoid barrier. Flt3\(^{Cre}\) lineage tracing and bone marrow transplantation showed that the precursors were derived from adult hematopoietic stem cells and were most likely continuously replaced via cell trafficking. Importantly, their occurrence was tied to the immunologic state of the central nervous system (CNS) and was diminished in the context of neuroinflammation and ischemic stroke. Our findings confirm the presence of myeloid progenitors at the meningeal border of the brain and lay the foundation to unravel their possible functions in CNS surveillance and local immune cell production.
KW - hematopoietic
KW - meninges
KW - mouse
KW - myeloid
KW - progenitor
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224452
VL - 39
IS - 2
SP - 227
EP - 239
ER -
TY - JOUR
A1 - Roy, Dipak Kumar
A1 - Tröster, Tobias
A1 - Fantuzzi, Felipe
A1 - Dewhurst, Rian D.
A1 - Lenczyk, Carsten
A1 - Radacki, Krzysztof
A1 - Pranckevicius, Conor
A1 - Engels, Bernd
A1 - Braunschweig, Holger
T1 - Isolation and Reactivity of an Antiaromatic s‐Block Metal Compound
JF - Angewandte Chemie International Edition
N2 - The concepts of aromaticity and antiaromaticity have a long history, and countless demonstrations of these phenomena have been made with molecules based on elements from the p, d, and f blocks of the periodic table. In contrast, the limited oxidation‐state flexibility of the s‐block metals has long stood in the way of their participation in sophisticated π‐bonding arrangements, and truly antiaromatic systems containing s‐block metals are altogether absent or remain poorly defined. Using spectroscopic, structural, and computational techniques, we present herein the synthesis and authentication of a heterocyclic compound containing the alkaline earth metal beryllium that exhibits significant antiaromaticity, and detail its chemical reduction and Lewis‐base‐coordination chemistry.
KW - antiaromaticity
KW - aromaticity
KW - beryllium
KW - heterocycles
KW - s-block metals
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224447
VL - 60
IS - 7
SP - 3812
EP - 3819
ER -
TY - JOUR
A1 - Dohrn, Maike F.
A1 - Ihne, Sandra
A1 - Hegenbart, Ute
A1 - Medina, Jessica
A1 - Züchner, Stephan L.
A1 - Coelho, Teresa
A1 - Hahn, Katrin
T1 - Targeting transthyretin ‐ Mechanism‐based treatment approaches and future perspectives in hereditary amyloidosis
JF - Journal of Neurochemistry
N2 - The liver‐derived, circulating transport protein transthyretin (TTR) is the cause of systemic hereditary (ATTRv) and wild‐type (ATTRwt) amyloidosis. TTR stabilization and knockdown are approved therapies to mitigate the otherwise lethal disease course. To date, the variety in phenotypic penetrance is not fully understood. This systematic review summarizes the current literature on TTR pathophysiology with its therapeutic implications. Tetramer dissociation is the rate‐limiting step of amyloidogenesis. Besides destabilizing TTR mutations, other genetic (RBP4, APCS, AR, ATX2, C1q, C3) and external (extracellular matrix, Schwann cell interaction) factors influence the type of onset and organ tropism. The approved small molecule tafamidis stabilizes the tetramer and significantly decelerates the clinical course. By sequence‐specific mRNA knockdown, the approved small interfering RNA (siRNA) patisiran and antisense oligonucleotide (ASO) inotersen both significantly reduce plasma TTR levels and improve neuropathy and quality of life compared to placebo. With enhanced hepatic targeting capabilities, GalNac‐conjugated siRNA and ASOs have recently entered phase III clinical trials. Bivalent TTR stabilizers occupy both binding groves in vitro, but have not been tested in trials so far. Tolcapone is another stabilizer with the potential to cross the blood–brain barrier, but its half‐life is short and liver failure a potential side effect. Amyloid‐directed antibodies and substances like doxycycline aim at reducing the amyloid load, however, none of the yet developed antibodies has successfully passed clinical trials. ATTR‐amyloidosis has become a model disease for pathophysiology‐based treatment. Further understanding of disease mechanisms will help to overcome the remaining limitations, including application burden, side effects, and blood–brain barrier permeability.
KW - amyloid‐directed antibodies
KW - ATTRv amyloidosis
KW - familial amyloid polyneuropathy (FAP)
KW - transthyretin
KW - TTR knockdown
KW - TTR stabilization
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224481
VL - 156
IS - 6
SP - 802
EP - 818
ER -
TY - JOUR
A1 - Heimberg, Linda
A1 - Knop, Stefan
T1 - Updated Perspectives on the Management of Relapsed and Refractory Multiple Myeloma
JF - Oncology Research and Treatment
N2 - Background: With the availability of T-cell-directed therapy and next-generation compounds of established classes of drugs, the treatment of relapsed/refractory (r/r) myeloma is getting more complex. However, treatment options in practice are limited by availability, approval, and patient comorbidity. The aim of this article is to provide a practical approach toward the choice of treatment for r/r myeloma patients. Summary: Regarding market authorization and current guidelines, at least in Germany, most patients nowadays will have received a doublet or triplet combination as first-line therapy containing a proteasome inhibitor and an immunomodulatory drug, mostly lenalidomide. We focus on the treatment options for patients that are ineligible for (another) stem cell transplantation. We will review treatment options for relapse after first- or second-line therapy and beyond third-line. Key Messages: There is promising data supporting the efficacy and safety of triplet combinations containing anti-CD38-monoclonal antibodies (anti-CD38 mAbs) at first or second relapse in combination with next-generation compounds. For the treatment beyond third-line, comparative studies are scarce but some promising compounds are available via conditional authorization, and there is more to come in the future. We will present some early phase trials featuring promising results.
KW - lenalidomide-refractory patients
KW - myeloma
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-249773
SN - 2296-5270
SN - 2296-5262
VL - 44
IS - 12
ER -
TY - JOUR
A1 - Plassmeier, Lars
A1 - Hankir, Mohammed K.
A1 - Seyfried, Florian
T1 - Impact of Excess Body Weight on Postsurgical Complications
JF - Visceral Medicine
N2 - Background: Obesity is considered a risk factor for postoperative complications as it can limit exposure to the operation field, thereby significantly prolonging surgery time. Obesity-associated comorbidities, such as low-grade systemic inflammation, impaired functional status, and type 2 diabetes, are independent risk factors for impaired anastomotic wound healing and nonsurgical site infections. If obesity itself is an independent risk factor for surgical complications remains controversial, but the reason for this is largely unexplored. Summary: A MEDLINE literature search was performed using the terms: “obesity,” “excess body weight,” and “surgical complications.” Out of 65,493 articles 432 meta-analyses were screened, of which 25 meta-analyses were on the subject. The vast majority of complex oncologic procedures in the field of visceral surgery have shown higher complication rates in obese patients. Meta-analyses from the last 10 to 15 years with high numbers of patients enrolled consistently have shown longer operation times, higher blood loss, longer hospital stay for colorectal procedures, oncologic upper gastrointestinal (GI) procedures, and pancreatic surgery. Interestingly, these negative effects seem not to affect the overall survival in oncologic patients, especially in esophageal resections. A selection bias in oncologic upper GI patients may have influenced the results with higher BMI in upper GI cancer to be a predictor for better nutritional and performance status. Key Messages: Contrary to bariatric surgery, only limited evidence indicated that site and type of surgery, the approach to the abdominal cavity (laparoscopic vs. open), institutional factors, and the type of perioperative care such as ERAS protocols may play a role in determining postsurgical complications in obese patients. The initial question remains therefore partially unanswered. Large nationwide register-based studies are necessary to better understand which aspects of obesity and its related comorbidities define it as a risk factor for surgical complications.
KW - obesity
KW - surgical complications
KW - laparoscopy
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244890
SN - 2297-4725
SN - 2297-475X
VL - 37
IS - 4
ER -
TY - JOUR
A1 - Geissler, Julia
A1 - Werner, Elisabeth
A1 - Dworschak, Wolfgang
A1 - Romanos, Marcel
A1 - Ratz, Christoph
T1 - Freiheitsentziehende Maßnahmen in bayerischen Heimeinrichtungen für Kinder, Jugendliche und junge Volljährige mit Intelligenzminderung
JF - Zeitschrift für Kinder- und Jugendpsychiatrie und Psychotherapie
N2 - Fragestellung: In Bayern leben etwa 10 % aller jungen Menschen mit Intelligenzminderung in Heimeinrichtungen. 2016 wurde in Presseberichten der Vorwurf unzulässiger freiheitsentziehender Maßnahmen formuliert. Im Rahmen des Projekts REDUGIA wurde in bayerischen Heimeinrichtungen eine repräsentative Erhebung zu freiheitsentziehenden Maßnahmen (FeM), herausforderndem Verhalten (hfV) und der Mitarbeiterbelastung (MaB) durchgeführt. Methodik: 65 Einrichtungen für junge Menschen mit Intelligenzminderung in Bayern wurde ein Fragebogen zu strukturellen Gegebenheiten sowie MaB, hfV und FeM zugesendet. Neben deskriptiven Auswertungen wurden korrelative Analysen bzw. Regressionsanalysen zum Zusammenhang zwischen hfV, FeM und MaB durchgeführt. Ergebnisse: Es wurden Daten zu 1839 Personen in 61 Einrichtungen erhoben. 84.3 % der Einrichtungen berichteten geringe Raten an hfV und FeM, während 15.7 % ein gehäuftes Vorkommen von hfV und FeM angaben. Auf n = 1809 Vollzeitäquivalente kam es innerhalb von 14 Tagen zu 639 körperlichen Angriffen durch Bewohner_innen. In 12 Monaten wurden problemverhaltensassoziiert 85 Krankmeldungen sowie 33 Versetzungsanträge/Kündigungen berichtet. Es zeigte sich ein signifikant positiver Zusammenhang zwischen hfV und FeM (R² = .307, F = 21.719, p < .001). Die Mitarbeiterbelastung korrelierte positiv mit hfV (r = .507, p < .001). Schlussfolgerungen: Die Studienbefunde weisen darauf hin, dass hfV sowie FeM bei jungen Menschen mit Intelligenzminderung kein flächendeckendes Phänomen darstellen, sondern sich auf wenige spezialisierte Einrichtungen fokussieren. Mögliche Maßnahmen zur Prävention von Problemverhalten und Freiheitsentzug werden diskutiert.
N2 - Objective: In Bavaria, around 10 % of youths with an intellectual disability (ID) live in residential facilities. In 2015, media raised accusations of inadmissible use of coercive measures. The REDUGIA project carried out a representative survey in Bavarian facilities regarding coercive measures (FeM), challenging behavior (hfV), and employee stress (MaB). Method: We sent a questionnaire concerning structural conditions, MaB, hfV and FeM to 65 Bavarian facilities for young people with ID. In addition to preparing descriptive evaluations, we performed correlative and regression analyses concerning the relationship between hfV, FeM, and MaB. Results: We retrieved data from 1,839 subjects in 61 facilities. 84.3 % of facilities reported low rates of hfV and FeM, while 15.7 % reported an increased incidence of hfV and FeM. For n = 1809 full-time position equivalents there were 639 physical attacks by residents over the course of 14 days. We observed 85 instances of sick leave and 33 transfer apllications/resignation associated with hfV. The frequency of hfV predicted the frequency of FeM (R² = 0.307, F = 21.719, p < .001). MaB correlated positively with hfV (r = 0.507, p < .001). Conclusions: The descriptive data indicate that hfV and FeM are not general phenomena but occur mainly in a circumscript number of highly specialized facilities. This emphasizes the need for prevention of hfV and FeM.
T2 - Freedom-restricting measures in Bavarian residential facilities for children, adolescents, and young adults with intellectual disabilities
KW - Geistige Behinderung
KW - herausforderndes Verhalten
KW - freiheitsentziehende Maßnahmen
KW - Heimeinrichtungen
KW - Mitarbeiterbelastung
KW - intellectual disability
KW - challenging behavior
KW - coercive measures
KW - residential institutions
KW - employee stress
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244859
SN - 1422-4917
SN - 1664-2880
VL - 49
IS - 4
ER -
TY - JOUR
A1 - Seeger, Jennifer
A1 - Lenhard, Wolfgang
A1 - Wisniewski, Katrin
T1 - Metakognitives Strategiewissen in sprachbezogenen Situationen : Interne Struktur und Validität des ScenEx
JF - Diagnostica
N2 - Studieren stellt hohe Anforderungen an selbstregulatorische Fähigkeiten und eigenverantwortlichen Umgang mit schwierigen Situationen. Aus den zusätzlichen sprachlichen Barrieren für ausländische Studierende erwachsen spezifische selbstregulatorische Aufgaben, wie der Umgang mit Verständnisproblemen in Vorlesungen. Da hierfür bisher kaum geeignete Erhebungsinstrumente existieren, versucht ScenEx diese Lücke zu schließen. Der Test erfasst das metakognitive Strategiewissen in sprachlich herausfordernden Situationen im Studienalltag. Anhand einer Stichprobe von 290 ausländischen Studierenden im ersten Fachsemester wird die psychometrische Qualität und interne Struktur des Instruments überprüft. ScenEx zeigt eine zufriedenstellende interne Konsistenz und gute Itemfit-Kennwerte, erwartungskonform liegen lokale stochastische Abhängigkeiten der Aufgaben innerhalb der Szenarien vor. Eine konfirmatorische Faktorenanalyse bestätigt die Grobstruktur der Szenarien und des Gesamtscores des Tests. Das Verfahren ist für die weitere Entwicklung der Sprachkompetenz über die anfängliche Sprachfähigkeit hinaus prädiktiv. ScenEx erweist sich insgesamt als ein reliables und valides Instrument zur Erfassung des Strategiewissens in schwierigen Situationen im Studium.
N2 - Studying at a university requires a high degree of self-reliance. Self-regulatory skills and the ability to independently handle difficult situations are important for successfully completing a degree. In addition, foreign students are faced with language-based challenges demanding specific self-regulatory skills, such as dealing with comprehension problems in lectures. To date, assessing these skills has been difficult because of a lack of suitable instruments. The ScenEx Questionnaire purports to close this gap by measuring metacognitive strategic knowledge in everyday study situations by posing language-based challenges, presented as scenarios. Using a sample of 290 foreign students in their first semester, we assessed the psychometric quality of ScenEx. ScenEx shows a satisfactory internal consistency and good item fit. A confirmatory factor analysis confirms the structure of the scenarios and the overall score of the test. The procedure predicts the further development of language competence beyond the initial stage. ScenEx is a valid and reliable instrument for assessing strategic knowledge regarding linguistically difficult situations at the university.
T2 - Metacognitive Strategic Knowledge in Language-Related Situations
KW - Selbstregulation
KW - Strategiewissen
KW - Bildungsausländer
KW - Studienerfolg
KW - Deutsch als Fremdsprache
KW - self-regulation
KW - strategic knowledge
KW - foreign students
KW - academic success
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242375
SN - 0012-1924
SN - 2190-622X
VL - 67
IS - 4
ER -
TY - JOUR
A1 - Böckler, Anne
A1 - Rennert, Annika
A1 - Raettig, Tim
T1 - Stranger, Lover, Friend?
BT - The Pain of Rejection Does Not Depend
JF - Social Psychology
N2 - Social exclusion, even from minimal game-based interactions, induces negative consequences. We investigated whether the nature of the relationship with the excluder modulates the effects of ostracism. Participants played a virtual ball-tossing game with a stranger and a friend (friend condition) or a stranger and their romantic partner (partner condition) while being fully included, fully excluded, excluded only by the stranger, or excluded only by their close other. Replicating previous findings, full exclusion impaired participants’ basic-need satisfaction and relationship evaluation most severely. While the degree of exclusion mattered, the relationship to the excluder did not: Classic null hypothesis testing and Bayesian statistics showed no modulation of ostracism effects depending on whether participants were excluded by a stranger, a friend, or their partner.
KW - interpersonal relationships
KW - ostracism
KW - rejection
KW - social exclusion
KW - social interaction
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238721
SN - 1864-9335
SN - 2151-2590
VL - 52
IS - 3
ER -
TY - JOUR
A1 - Wittkowski, Joachim
A1 - Scheuchenpflug, Rainer
T1 - Evidence on the Conceptual Distinctness of Normal Grief From Depression
BT - A Multi-Faceted Analysis of Differential Validity
JF - European Journal of Health Psychology
N2 - Background: The distinctness of grief from depression has been the subject of a long scholarly debate, even influencing definitions of diagnostic criteria. Aims: This study aims at clarifying the issue by a multifaceted analysis of data from a large German sample. Method: A community sample of 406 bereaved persons answered the Wuerzburg Grief Inventory (WGI), a multidimensional grief questionnaire designed to measure normal grief in the German language, and the General Depression Scale – Short Version (GDS-S), a self-report depression scale. Data were analyzed by factor analysis to identify structural (dis-)similarities of the constructs, and analysis of variance (ANOVA) to identify the influence of the factors relationship to the deceased, type of death, and time since loss on grief measures and depression scores. Results: Factor analysis clustered items referring to grief-related impairments and depression into one factor, items referring to other dimensions of grief on separate factors, however. Relationship to the deceased influenced the grief measures impairments and nearness to the deceased, but not depression scores if controlled for impairments. Type of death showed specific effects on grief scores, but not on depression scores. Time since loss influenced grief scores, but not depression scores. Limitations: The analysis is based on a self-selected community sample of grieving persons, self-report measures, and in part, on cross-sectional data. Conclusion: Factor analysis and objective data show a clear distinction of dimensions of grief and depression. The human experience of grief contains a sense of nearness to the lost person, feelings of guilt, and positive aspects of the loss experience in addition to components resembling depression.
KW - depression
KW - grief
KW - time since loss
KW - type of death
KW - Wuerzburg Grief Inventory (WGI)
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236531
SN - 2512-8442
SN - 2512-8450
VL - 28
IS - 3
SP - 101-110
ER -
TY - JOUR
A1 - Bunzmann, Nikolai
A1 - Krugmann, Benjamin
A1 - Weissenseel, Sebastian
A1 - Kudriashova, Liudmila
A1 - Ivaniuk, Khrystyna
A1 - Stakhira, Pavlo
A1 - Cherpak, Vladyslav
A1 - Chapran, Marian
A1 - Grybauskaite‐Kaminskiene, Gintare
A1 - Grazulevicius, Juozas Vidas
A1 - Dyakonov, Vladimir
A1 - Sperlich, Andreas
T1 - Spin‐ and Voltage‐Dependent Emission from Intra‐ and Intermolecular TADF OLEDs
JF - Advanced Electronic Materials
N2 - Organic light emitting diodes (OLEDs) based on thermally activated delayed fluorescence (TADF) utilize molecular systems with a small energy splitting between singlet and triplet states. This can either be realized in intramolecular charge transfer states of molecules with near‐orthogonal donor and acceptor moieties or in intermolecular exciplex states formed between a suitable combination of individual donor and acceptor materials. Here, 4,4′‐(9H,9′H‐[3,3′‐bicarbazole]‐9,9′‐diyl)bis(3‐(trifluoromethyl) benzonitrile) (pCNBCzoCF\(_{3}\)) is investigated, which shows intramolecular TADF but can also form exciplex states in combination with 4,4′,4′′‐tris[phenyl(m‐tolyl)amino]triphenylamine (m‐MTDATA). Orange emitting exciplex‐based OLEDs additionally generate a sky‐blue emission from the intramolecular emitter with an intensity that can be voltage‐controlled. Electroluminescence detected magnetic resonance (ELDMR) is applied to study the thermally activated spin‐dependent triplet to singlet up‐conversion in operating devices. Thereby, intermediate excited states involved in OLED operation can be investigated and the corresponding activation energy for both, intra‐ and intermolecular based TADF can be derived. Furthermore, a lower estimate is given for the extent of the triplet wavefunction to be ≥ 1.2 nm. Photoluminescence detected magnetic resonance (PLDMR) reveals the population of molecular triplets in optically excited thin films. Overall, the findings allow to draw a comprehensive picture of the spin‐dependent emission from intra‐ and intermolecular TADF OLEDs.
KW - color tuning
KW - exciplexes
KW - organic light emitting diodes
KW - spin
KW - triplets
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224434
VL - 7
IS - 3
ER -
TY - JOUR
A1 - Mechau, Jannik
A1 - Frank, Andreas
A1 - Bakirci, Ezgi
A1 - Gumbel, Simon
A1 - Jungst, Tomasz
A1 - Giesa, Reiner
A1 - Groll, Jürgen
A1 - Dalton, Paul D.
A1 - Schmidt, Hans‐Werner
T1 - Hydrophilic (AB)\(_{n}\) Segmented Copolymers for Melt Extrusion‐Based Additive Manufacturing
JF - Macromolecular Chemistry and Physics
N2 - Several manufacturing technologies beneficially involve processing from the melt, including extrusion‐based printing, electrospinning, and electrohydrodynamic jetting. In this study, (AB)\(_{n}\) segmented copolymers are tailored for melt‐processing to form physically crosslinked hydrogels after swelling. The copolymers are composed of hydrophilic poly(ethylene glycol)‐based segments and hydrophobic bisurea segments, which form physical crosslinks via hydrogen bonds. The degree of polymerization was adjusted to match the melt viscosity to the different melt‐processing techniques. Using extrusion‐based printing, a width of approximately 260 µm is printed into 3D constructs, with excellent interlayer bonding at fiber junctions, due to hydrogen bonding between the layers. For melt electrospinning, much thinner fibers in the range of about 1–15 µm are obtained and produced in a typical nonwoven morphology. With melt electrowriting, fibers are deposited in a controlled way to well‐defined 3D constructs. In this case, multiple fiber layers fuse together enabling constructs with line width in the range of 70 to 160 µm. If exposed to water the printed constructs swell and form physically crosslinked hydrogels that slowly disintegrate, which is a feature for soluble inks within biofabrication strategies. In this context, cytotoxicity tests confirm the viability of cells and thus demonstrating biocompatibility of this class of copolymers.
KW - 3D printing
KW - (AB)\(_{n}\) segmented copolymers
KW - biocompatibility
KW - melt electrowriting
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224513
VL - 222
IS - 1
ER -
TY - JOUR
A1 - Krahfuss, Mirjam J.
A1 - Radius, Udo
T1 - N‐Heterocyclic Silylene Main Group Element Chemistry: Adduct Formation, Insertion into E−X Bonds and Cyclization of Organoazides
JF - European Journal of Inorganic Chemistry
N2 - Investigations concerning the reactivity of the N‐heterocyclic silylene Dipp\(_{2}\)NHSi (1, 1,3‐bis(2,6‐diisopropylphenyl)‐1,3‐diaza‐2‐silacyclopent‐4‐en‐2‐ylidene) towards selected alanes and boranes, elemental halides X\(_{2}\) (X=Br, I), selected halide containing substrates such as tin chlorides and halocarbons, as well as organoazides are presented. The NHSi adducts Dipp\(_{2}\)NHSi⋅AlI\(_{3}\) (2), Dipp\(_{2}\)NHSi⋅Al(C\(_{6}\)F\(_{5}\))\(_{3}\) (3), and Dipp\(_{2}\)NHSi⋅B(C\(_{6}\)F\(_{5}\))\(_{3}\) (4) were formed by the reaction of Dipp\(_{2}\)NHSi with the corresponding Lewis acids AlI\(_{3}\), Al(C\(_{6}\)F\(_{6}\))\(_{3}\) and B(C\(_{6}\)F\(_{5}\))\(_{3}\). Adducts 3 and 4 were tested with respect to their ability to activate small organic molecules, but no frustrated Lewis pair reactivity was observed. Reactions of Dipp\(_{2}\)NHSi with Br\(_{2}\), I\(_{2}\), Ph\(_{2}\)SnCl\(_{2}\) and Me\(_{3}\)SnCl led to formation of Dipp\(_{2}\)NHSiBr\(_{2}\) (5), Dipp\(_{2}\)NHSiI\(_{2}\) (6), Dipp\(_{2}\)NHSiCl\(_{2}\) (7) and {(Me\(_{3}\)Sn)N(Dipp)CH}\(_{2}\) (8), respectively. The reaction with the halocarbons methyl iodide, benzyl chloride, and benzyl bromide afforded the insertion products Dipp\(_{2}\)NHSi(I)(CH\(_{3}\)) (9), Dipp\(_{2}\)NHSi(Cl)(CH\(_{2}\)Ph) (10) and Dipp\(_{2}\)NHSi(Br)(CH\(_{2}\)Ph) (11). Reaction of Dipp\(_{2}\)NHSi with the organoazides Ad‐N\(_{3}\) (Ad=adamantyl) and TMS‐N\(_{3}\) (TMS=trimethylsilyl) led to the formation of 1‐Dipp\(_{2}\)NHSi‐2,5‐bis(adamantyl)‐tetrazoline (12) and bis(trimethylsilyl)amido azido silane (13), respectively. For 2,6‐(diphenyl)phenyl‐N\(_{3}\) C−H activation occurs and a cyclosilamine 14 was isolated.
KW - arbenes
KW - E−X bond activation
KW - acid/base adducts
KW - Organoazides
KW - Silylenes
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224507
VL - 2021
IS - 6
SP - 548
EP - 561
ER -
TY - JOUR
A1 - Renner, Rebecca
A1 - Mahlmeister, Bernhard
A1 - Anhalt, Olga
A1 - Stolte, Matthias
A1 - Würthner, Frank
T1 - Chiral Perylene Bisimide Dyes by Interlocked Arene Substituents in the Bay Area
JF - Chemistry - A European Journal
N2 - A series of perylene bisimide (PBI) dyes bearing various aryl substituents in 1,6,7,12 bay positions has been synthesized by Suzuki cross-coupling reaction. These molecules exhibit an exceptionally large and conformationally fixed twist angle of the PBI π-core due to the high steric congestion imparted by the aryl substituents in bay positions. Single crystal X-ray analyses of phenyl-, naphthyl- and pyrenyl-functionalized PBIs reveal interlocked π-π-stacking motifs, leading to conformational chirality and the possibility for the isolation of enantiopure atropoisomers by semipreparative HPLC. The interlocked arrangement endows these molecules with substantial racemization barriers of about 120 kJ mol\(^{−1}\) for the tetraphenyl- and tetra-2-naphthyl-substituted derivatives, which is among the highest racemization barriers for axially chiral PBIs. Variable temperature NMR studies reveal the presence of a multitude of up to fourteen conformational isomers in solution that are interconverted via smaller activation barriers of about 65 kJ mol\(^{−1}\). The redox and optical properties of these core-twisted PBIs have been characterized by cyclic voltammetry, UV/Vis/NIR and fluorescence spectroscopy and their respective atropo-enantiomers were further characterized by circular dichroism (CD) and circular polarized luminescence (CPL) spectroscopy.
KW - Suzuki coupling
KW - perylenebisimide dyes
KW - circular polarized luminescence
KW - chirality
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-249070
VL - 27
IS - 46
SP - 11997
EP - 12006
ER -
TY - JOUR
A1 - Rupp, Mira T.
A1 - Auvray, Thomas
A1 - Hanan, Garry S.
A1 - Kurth, Dirk G.
T1 - Electrochemical and photophysical study of homoleptic and heteroleptic methylated Ru(II) Bis-terpyridine complexes
JF - European Journal of Inorganic Chemistry
N2 - In this study, we investigate the impact of N-methylation on the electronic and photophysical properties of both homoleptic and heteroleptic Ru(II) bis-terpyridine complexes based on the recently reported ligand 4’-(4-bromophenyl)-4,4’’’: 4’’,4’’’’-dipyr-idinyl-2,2’ : 6’,2’’-terpyridine (Bipytpy), with pyridine substituents in the 4- and 4’’-position. The first reduction of the methylated complexes takes place at the pyridinium site and is observed as multi-electron process. Following N-methylation, the complexes exhibit higher luminescence quantum yields and longer excited-state lifetimes. Interestingly, the photophysical properties of the heteroleptic and homoleptic complexes are rather similar. TD-DFT calculations support the experimental results. Furthermore, the complexes are tested as photosensitizers for photocatalytic hydrogen production, as the parent complex 1[Ru(Bipytpy)(Tolyltpy)](PF \(_6\))\(_2\) (Tolyltpy: 4’-tolyl-2,2’: 6’,2’’-terpyri-dine) was recently shown to be active and highly stable underphotocatalytic conditions. However, the methylated complexes reported herein are inactive as photosensitizers under the chosen conditions, presumably due to loss of the methyl groups, converting them to the non-methylated parent complexes.
KW - Ruthenium
KW - Luminescence
KW - Electrochemistry
KW - Ligand effects
KW - Photocatalysis
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-248769
VL - 2021
IS - 28
SP - 2822
EP - 2829
ER -
TY - JOUR
A1 - Chen, Chunguang
A1 - Rawat, Divya
A1 - Samikannu, Balaji
A1 - Bender, Markus
A1 - Preissner, Klaus T.
A1 - Linn, Thomas
T1 - Platelet glycoprotein VI‐dependent thrombus stabilization is essential for the intraportal engraftment of pancreatic islets
JF - American Journal of Transplantation
N2 - Platelet activation and thrombus formation have been implicated to be detrimental for intraportal pancreatic islet transplants. The platelet‐specific collagen receptor glycoprotein VI (GPVI) plays a key role in thrombosis through cellular activation and the subsequent release of secondary mediators. In aggregometry and in a microfluidic dynamic assay system modeling flow in the portal vein, pancreatic islets promoted platelet aggregation and triggered thrombus formation, respectively. While platelet GPVI deficiency did not affect the initiation of these events, it was found to destabilize platelet aggregates and thrombi in this process. Interestingly, while no major difference was detected in early thrombus formation after intraportal islet transplantation, genetic GPVI deficiency or acute anti‐GPVI treatment led to an inferior graft survival and function in both syngeneic mouse islet transplantation and xenogeneic human islet transplantation models. These results demonstrate that platelet GPVI signaling is indispensable in stable thrombus formation induced by pancreatic islets. GPVI deficiency resulted in thrombus destabilization and inferior islet engraftment indicating that thrombus formation is necessary for a successful intraportal islet transplantation in which platelets are active modulators.
KW - basic (laboratory) research / science
KW - coagulation and hemostasis
KW - graft survival
KW - islet transplantation
KW - molecular biology
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224471
VL - 21
SP - 2079
EP - 2089
ER -
TY - JOUR
A1 - Cullmann, Katharina
A1 - Jahn, Magdalena
A1 - Spindler, Markus
A1 - Schenk, Franziska
A1 - Manukjan, Georgi
A1 - Mucci, Adele
A1 - Steinemann, Doris
A1 - Boller, Klaus
A1 - Schulze, Harald
A1 - Bender, Markus
A1 - Moritz, Thomas
A1 - Modlich, Ute
T1 - Forming megakaryocytes from murine‐induced pluripotent stem cells by the inducible overexpression of supporting factors
JF - Research and Practice in Thrombosis and Haemostasis
N2 - Background
Platelets are small anucleate cells that circulate in the blood in a resting state but can be activated by external cues. In case of need, platelets from blood donors can be transfused. As an alternative source, platelets can be produced from induced pluripotent stem cells (iPSCs); however, recovered numbers are low.
Objectives
To optimize megakaryocyte (MK) and platelet output from murine iPSCs, we investigated overexpression of the transcription factors GATA‐binding factor 1 (GATA1); nuclear factor, erythroid 2; and pre–B‐cell leukemia transcription factor 1 (Pbx1) and a hyperactive variant of the small guanosine triphosphatase RhoA (RhoAhc).
Methods
To avoid off‐target effects, we generated iPSCs carrying the reverse tetracycline‐responsive transactivator M2 (rtTA‐M2) in the Rosa26 locus and expressed the factors from Tet‐inducible gammaretroviral vectors. Differentiation of iPSCs was initiated by embryoid body (EB) formation. After EB dissociation, early hematopoietic progenitors were enriched and cocultivated on OP9 feeder cells with thrombopoietin and stem cell factor to induce megakaryocyte (MK) differentiation.
Results
Overexpression of GATA1 and Pbx1 increased MK output 2‐ to 2.5‐fold and allowed prolonged collection of MK. Cytologic and ultrastructural analyses identified typical MK with enlarged cells, multilobulated nuclei, granule structures, and an internal membrane system. However, GATA1 and Pbx1 expression did not improve MK maturation or platelet release, although in vitro–generated platelets were functional in spreading on fibrinogen or collagen‐related peptide.
Conclusion
We demonstrate that the use of rtTA‐M2 transgenic iPSCs transduced with Tet‐inducible retroviral vectors allowed for gene expression at later time points during differentiation. With this strategy we could identify factors that increased in vitro MK production.
KW - genetic modification
KW - iPS cells
KW - megakaryocytes
KW - retroviral vectors
KW - Tet‐inducible system
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224565
VL - 5
IS - 1
SP - 111
EP - 124
ER -
TY - JOUR
A1 - Boff, Samuel
A1 - Friedel, Anna
T1 - Dynamics of nest occupation and homing of solitary bees in painted trap nests
JF - Ecological Entomology
N2 - 1. The oil‐collecting bee Centris analis (Fabricius, 1804) is an important pollinator for the Neotropical region. The species can be attracted to nest in human‐made cavities. Such trap nests or insect hotels offer the opportunity to study the behaviour of populations in semifield conditions.
2. We studied a newly established trap nest aggregation of C. analis in Mato Grosso do Sul, Brazil and tested the effect that differentially painted nesting options have on the rate of nest foundation, and on the ability of relocating the nest when returning from a foraging trip (homing behaviour). Moreover, we tested if the duration of foraging trips decreased with time.
3. We found that females preferred to nest in painted nests compared to unpainted nests, with blue nests being the most occupied ones, followed by purple, yellow, white, and green. Furthermore, bees improved their homing behaviour with time, however, nest colour did not seem to have an effect on this process. Moreover, we found that bees reduce the duration of their foraging trips with time. This could be an indicator of improved foraging efficiency through learning.
4. These findings could inform a new and fruitful line of research on the behaviour and ecology of trap nesting solitary bees.
KW - foraging activities
KW - nesting ecology
KW - oil bees
KW - painted nest preference
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224605
VL - 46
IS - 2
SP - 496
EP - 499
ER -
TY - JOUR
A1 - Welker, Armin
A1 - Kersten, Christian
A1 - Müller, Christin
A1 - Madhugiri, Ramakanth
A1 - Zimmer, Collin
A1 - Müller, Patrick
A1 - Zimmermann, Robert
A1 - Hammerschmidt, Stefan
A1 - Maus, Hannah
A1 - Ziebuhr, John
A1 - Sotriffer, Christoph
A1 - Schirmeister, Tanja
T1 - Structure‐Activity Relationships of Benzamides and Isoindolines Designed as SARS‐CoV Protease Inhibitors Effective against SARS‐CoV‐2
JF - ChemMedChem
N2 - Inhibition of coronavirus (CoV)‐encoded papain‐like cysteine proteases (PL\(^{pro}\)) represents an attractive strategy to treat infections by these important human pathogens. Herein we report on structure‐activity relationships (SAR) of the noncovalent active‐site directed inhibitor (R)‐5‐amino‐2‐methyl‐N‐(1‐(naphthalen‐1‐yl)ethyl) benzamide (2 b), which is known to bind into the S3 and S4 pockets of the SARS‐CoV PL\(^{pro}\). Moreover, we report the discovery of isoindolines as a new class of potent PL\(^{pro}\) inhibitors. The studies also provide a deeper understanding of the binding modes of this inhibitor class. Importantly, the inhibitors were also confirmed to inhibit SARS‐CoV‐2 replication in cell culture suggesting that, due to the high structural similarities of the target proteases, inhibitors identified against SARS‐CoV PL\(^{pro}\) are valuable starting points for the development of new pan‐coronaviral inhibitors.
KW - antiviral agents
KW - computational chemistry
KW - drug design
KW - protease inhibitors
KW - structure-activity relationships
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225700
VL - 16
IS - 2
SP - 340
EP - 354
ER -
TY - JOUR
A1 - Romero‐Olmedo, Addi J.
A1 - Schulz, Axel R.
A1 - Huber, Magdalena
A1 - Brehm, Corinna U.
A1 - Chang, Hyun‐Dong
A1 - Chiarolla, Cristina M.
A1 - Bopp, Tobias
A1 - Skevaki, Chrysanthi
A1 - Berberich‐Siebelt, Friederike
A1 - Radbruch, Andreas
A1 - Mei, Henrik E.
A1 - Lohoff, Michael
T1 - Deep phenotypical characterization of human CD3\(^{+}\)CD56\(^{+}\) T cells by mass cytometry
JF - European Journal of Immunology
N2 - CD56\(^{+}\) T cells are a group of pro‐inflammatory CD3\(^{+}\) lymphocytes with characteristics of natural killer cells, being involved in antimicrobial immune defense. Here, we performed deep phenotypic profiling of CD3\(^{+}\)CD56\(^{+}\) cells in peripheral blood of normal human donors and individuals sensitized to birch‐pollen or/and house dust mite by high‐dimensional mass cytometry combined with manual and computational data analysis. A co‐regulation between major conventional T‐cell subsets and their respective CD3\(^{+}\)CD56\(^{+}\) cell counterparts appeared restricted to CD8\(^{+}\), MAIT, and TCRγδ\(^{+}\) T‐cell compartments. Interestingly, we find a co‐regulation of several CD3\(^{+}\)CD56\(^{+}\) cell subsets in allergic but not in healthy individuals. Moreover, using FlowSOM, we distinguished a variety of CD56\(^{+}\) T‐cell phenotypes demonstrating a hitherto underestimated heterogeneity among these cells. The novel CD3\(^{+}\)CD56\(^{+}\) subset description comprises phenotypes superimposed with naive, memory, type 1, 2, and 17 differentiation stages, in part represented by a phenotypical continuum. Frequencies of two out of 19 CD3\(^{+}\)CD56\(^{+}\) FlowSOM clusters were significantly diminished in allergic individuals, demonstrating less frequent presence of cells with cytolytic, presumably protective, capacity in these donors consistent with defective expansion or their recruitment to the affected tissue. Our results contribute to defining specific cell populations to be targeted during therapy for allergic conditions.
KW - allergy
KW - CD56
KW - human
KW - mass cytometry
KW - T cells
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225699
VL - 51
IS - 3
SP - 672
EP - 681
ER -
TY - JOUR
A1 - Doryab, Ali
A1 - Taskin, Mehmet Berat
A1 - Stahlhut, Philipp
A1 - Schröppel, Andreas
A1 - Wagner, Darcy E.
A1 - Groll, Jürgen
A1 - Schmid, Otmar
T1 - A Biomimetic, Copolymeric Membrane for Cell‐Stretch Experiments with Pulmonary Epithelial Cells at the Air‐Liquid Interface
JF - Advanced Functional Materials
N2 - Chronic respiratory diseases are among the leading causes of death worldwide, but only symptomatic therapies are available for terminal illness. This in part reflects a lack of biomimetic in vitro models that can imitate the complex environment and physiology of the lung. Here, a copolymeric membrane consisting of poly(ε‐)caprolactone and gelatin with tunable properties, resembling the main characteristics of the alveolar basement membrane is introduced. The thin bioinspired membrane (≤5 μm) is stretchable (up to 25% linear strain) with appropriate surface wettability and porosity for culturing lung epithelial cells under air–liquid interface conditions. The unique biphasic concept of this membrane provides optimum characteristics for initial cell growth (phase I) and then switch to biomimetic properties for cyclic cell‐stretch experiments (phase II). It is showed that physiologic cyclic mechanical stretch improves formation of F‐actin cytoskeleton filaments and tight junctions while non‐physiologic over‐stretch induces cell apoptosis, activates inflammatory response (IL‐8), and impairs epithelial barrier integrity. It is also demonstrated that cyclic physiologic stretch can enhance the cellular uptake of nanoparticles. Since this membrane offers considerable advantages over currently used membranes, it may lead the way to more biomimetic in vitro models of the lung for translation of in vitro response studies into clinical outcome.
KW - alveolar‐capillary barrier
KW - cyclic mechanical stretch
KW - hybrid polymers
KW - in vitro cell‐stretch model
KW - tunable ultra‐thin biphasic membrane
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225645
VL - 31
IS - 10
ER -
TY - JOUR
A1 - Hanft, Anna
A1 - Radacki, Krzysztof
A1 - Lichtenberg, Crispin
T1 - Cationic Bismuth Aminotroponiminates: Charge Controls Redox Properties
JF - Chemistry – A European Journal
N2 - The behavior of the redox‐active aminotroponiminate (ATI) ligand in the coordination sphere of bismuth has been investigated in neutral and cationic compounds, [Bi(ATI)\(_{3}\)] and [Bi(ATI)\(_{2}\)L\(_{n}\)][A] (L=neutral ligand; n=0, 1; A=counteranion). Their coordination chemistry in solution and in the solid state has been analyzed through (variable‐temperature) NMR spectroscopy, line‐shape analysis, and single‐crystal X‐ray diffraction analyses, and their Lewis acidity has been evaluated by using the Gutmann–Beckett method (and modifications thereof). Cyclic voltammetry, in combination with DFT calculations, indicates that switching between ligand‐ and metal‐centered redox events is possible by altering the charge of the compounds from 0 in neutral species to +1 in cationic compounds. This adds important facets to the rich redox chemistry of ATIs and to the redox chemistry of bismuth compounds, which is, so far, largely unexplored.
KW - aminotroponiminates
KW - bismuth
KW - cationic species
KW - redox chemistry
KW - redox-active ligands
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225669
VL - 27
IS - 20
SP - 6230
EP - 6239
ER -
TY - JOUR
A1 - Budiman, Yudha P.
A1 - Lorenzen, Sabine
A1 - Liu, Zhiqiang
A1 - Radius, Udo
A1 - Marder, Todd B.
T1 - Base‐Free Pd‐Catalyzed C−Cl Borylation of Fluorinated Aryl Chlorides
JF - Chemistry – A European Journal
N2 - Catalytic C−X borylation of aryl halides containing two ortho‐fluorines has been found to be challenging, as most previous methods require stoichiometric amounts of base and the polyfluorinated aryl boronates suffer from protodeboronation, which is accelerated by ortho‐fluorine substituents. Herein, we report that a combination of Pd(dba)2 (dba=dibenzylideneacetone) with SPhos (2‐dicyclohexylphosphino‐2’,6’‐dimethoxybiphenyl) as a ligand is efficient to catalyze the C‐Cl borylation of aryl chlorides containing two ortho‐fluorine substituents. This method, conducted under base‐free conditions, is compatible with the resulting di‐ortho‐fluorinated aryl boronate products which are sensitive to base.
KW - boronate ester
KW - borylation
KW - cross-coupling
KW - fluoroarene
KW - palladium-catalyzed
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225687
VL - 27
IS - 11
SP - 3869
EP - 3874
ER -
TY - JOUR
A1 - Weich, Alexander
A1 - Werner, Rudolf A.
A1 - Buck, Andreas K.
A1 - Hartrampf, Philipp E.
A1 - Serfling, Sebastian E.
A1 - Scheurlen, Michael
A1 - Wester, Hans-Jürgen
A1 - Meining, Alexander
A1 - Kircher, Stefan
A1 - Higuchi, Takahiro
A1 - Pomper, Martin G.
A1 - Rowe, Steven P.
A1 - Lapa, Constantin
A1 - Kircher, Malte
T1 - CXCR4-Directed PET/CT in Patients with Newly Diagnosed Neuroendocrine Carcinomas
JF - Diagnostics
N2 - We aimed to elucidate the diagnostic potential of the C-X-C motif chemokine receptor 4 (CXCR4)-directed positron emission tomography (PET) tracer \(^{68}\)Ga-Pentixafor in patients with poorly differentiated neuroendocrine carcinomas (NEC), relative to the established reference standard \(^{18}\)F-FDG PET/computed tomography (CT). In our database, we retrospectively identified 11 treatment-naïve patients with histologically proven NEC, who underwent \(^{18}\)F-FDG and CXCR4-directed PET/CT for staging and therapy planning. The images were analyzed on a per-patient and per-lesion basis and compared to immunohistochemical staining (IHC) of CXCR4 from PET-guided biopsies. \(^{68}\)Ga-Pentixafor visualized tumor lesions in 10/11 subjects, while \(^{18}\)F-FDG revealed sites of disease in all 11 patients. Although weak to moderate CXCR4 expression could be corroborated by IHC in 10/11 cases, \(^{18}\)F-FDG PET/CT detected significantly more tumor lesions (102 vs. 42; total lesions, n = 107; p < 0.001). Semi-quantitative analysis revealed markedly higher 18F-FDG uptake as compared to \(^{68}\)Ga-Pentixafor (maximum and mean standardized uptake values (SUV) and tumor-to-background ratios (TBR) of cancerous lesions, SUVmax: 12.8 ± 9.8 vs. 5.2 ± 3.7; SUVmean: 7.4 ± 5.4 vs. 3.1 ± 3.2, p < 0.001; and, TBR 7.2 ± 7.9 vs. 3.4 ± 3.0, p < 0.001). Non-invasive imaging of CXCR4 expression in NEC is inferior to the reference standard \(^{18}\)F-FDG PET/CT.
KW - CXCR4
KW - NET
KW - NEC
KW - 68Ga-Pentixafor
KW - 18F-FDG
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234231
SN - 2075-4418
VL - 11
IS - 4
ER -
TY - JOUR
A1 - Mönius, Katja
T1 - Eigenvalues of zero-divisor graphs of finite commutative rings
JF - Journal of Algebraic Combinatorics
N2 - We investigate eigenvalues of the zero-divisor graph Γ(R) of finite commutative rings R and study the interplay between these eigenvalues, the ring-theoretic properties of R and the graph-theoretic properties of Γ(R). The graph Γ(R) is defined as the graph with vertex set consisting of all nonzero zero-divisors of R and adjacent vertices x, y whenever xy=0. We provide formulas for the nullity of Γ(R), i.e., the multiplicity of the eigenvalue 0 of Γ(R). Moreover, we precisely determine the spectra of \(\Gamma ({\mathbb {Z}}_p \times {\mathbb {Z}}_p \times {\mathbb {Z}}_p)\) and \(\Gamma ({\mathbb {Z}}_p \times {\mathbb {Z}}_p \times {\mathbb {Z}}_p \times {\mathbb {Z}}_p)\) for a prime number p. We introduce a graph product ×Γ with the property that Γ(R)≅Γ(R\(_1\))×Γ⋯×ΓΓ(R\(_r\)) whenever R≅R\(_1\)×⋯×R\(_r\). With this product, we find relations between the number of vertices of the zero-divisor graph Γ(R), the compressed zero-divisor graph, the structure of the ring R and the eigenvalues of Γ(R).
KW - EJMA-D-19-00287
KW - Zero-divisor graphs
KW - Graph eigenvalues
KW - Graphnullity
KW - Graph products
KW - Local rings
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232792
SN - 0925-9899
VL - 54
ER -
TY - JOUR
A1 - Grob, Robin
A1 - Tritscher, Clara
A1 - Grübel, Kornelia
A1 - Stigloher, Christian
A1 - Groh, Claudia
A1 - Fleischmann, Pauline N.
A1 - Rössler, Wolfgang
T1 - Johnston's organ and its central projections in Cataglyphis desert ants
JF - Journal of Comparative Neurology
N2 - The Johnston's organ (JO) in the insect antenna is a multisensory organ involved in several navigational tasks including wind‐compass orientation, flight control, graviception, and, possibly, magnetoreception. Here we investigate the three dimensional anatomy of the JO and its neuronal projections into the brain of the desert ant Cataglyphis, a marvelous long‐distance navigator. The JO of C. nodus workers consists of 40 scolopidia comprising three sensory neurons each. The numbers of scolopidia slightly vary between different sexes (female/male) and castes (worker/queen). Individual scolopidia attach to the intersegmental membrane between pedicel and flagellum of the antenna and line up in a ring‐like organization. Three JO nerves project along the two antennal nerve branches into the brain. Anterograde double staining of the antennal afferents revealed that JO receptor neurons project to several distinct neuropils in the central brain. The T5 tract projects into the antennal mechanosensory and motor center (AMMC), while the T6 tract bypasses the AMMC via the saddle and forms collaterals terminating in the posterior slope (PS) (T6I), the ventral complex (T6II), and the ventrolateral protocerebrum (T6III). Double labeling of JO and ocellar afferents revealed that input from the JO and visual information from the ocelli converge in tight apposition in the PS. The general JO anatomy and its central projection patterns resemble situations in honeybees and Drosophila. The multisensory nature of the JO together with its projections to multisensory neuropils in the ant brain likely serves synchronization and calibration of different sensory modalities during the ontogeny of navigation in Cataglyphis.
KW - ant brain
KW - chordotonal organ
KW - graviception
KW - magnetic compass
KW - multisensory integration
KW - navigation
KW - wind compass
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225679
VL - 529
IS - 8
SP - 2138
EP - 2155
ER -
TY - JOUR
A1 - Full, Julian
A1 - Panchal, Santosh P.
A1 - Götz, Julian
A1 - Krause, Ana‐Maria
A1 - Nowak‐Król, Agnieszka
T1 - Modular Synthesis of Organoboron Helically Chiral Compounds: Cutouts from Extended Helices
JF - Angewandte Chemie International Edition
N2 - Two types of helically chiral compounds bearing one and two boron atoms were synthesized by a modular approach. Formation of the helical scaffolds was executed by the introduction of boron to flexible biaryl and triaryl derived from small achiral building blocks. All‐ortho‐fused azabora[7]helicenes feature exceptional configurational stability, blue or green fluorescence with quantum yields (Φ\(_{fl}\)) of 18–24 % in solution, green or yellow solid‐state emission (Φ\(_{fl}\) up to 23 %), and strong chiroptical response with large dissymmetry factors of up to 1.12×10\(^{-2}\). Azabora[9]helicenes consisting of angularly and linearly fused rings are blue emitters exhibiting Φ\(_{fl}\) of up to 47 % in CH\(_{2}\)Cl\(_{2}\) and 25 % in the solid state. As revealed by the DFT calculations, their P–M interconversion pathway is more complex than that of H1. Single‐crystal X‐ray analysis shows clear differences in the packing arrangement of methyl and phenyl derivatives. These molecules are proposed as primary structures of extended helices.
KW - chirality
KW - circular dichroism
KW - fluorescence
KW - helicene
KW - organoboron
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225775
VL - 60
IS - 8
SP - 4350
EP - 4357
ER -
TY - JOUR
A1 - Urlaub, Jonas
A1 - Kaiser, Reinhard P.
A1 - Scherf‐Clavel, Oliver
A1 - Bolm, Carsten
A1 - Holzgrabe, Ulrike
T1 - Investigation of isomerization of dexibuprofen in a ball mill using chiral capillary electrophoresis
JF - Electrophoresis
N2 - Besides the racemate, the S‐enantiomer of ibuprofen (Ibu) is used for the treatment of inflammation and pain. Since the configurational stability of S‐Ibu in solid state is of interest, it was studied by means of ball milling experiments. For the evaluation of the enantiomeric composition, a chiral CE method was developed and validated according to the ICH guideline Q2(R1). The addition of Mg\(^{2+}\), Ca\(^{2+}\), or Zn\(^{2+}\) ions to the background electrolyte (BGE) was found to improve Ibu enantioresolution. Chiral separation of Ibu enantiomers was achieved on a 60.2 cm (50.0 cm effective length) x 75 μm fused‐silica capillary using a background electrolyte (BGE) composed of 50 mM sodium acetate, 10 mM magnesium acetate tetrahydrate, and 35 mM heptakis‐(2,3,6‐tri‐O‐methyl)‐β‐cyclodextrin (TM‐β‐CD) as chiral selector. The quantification of R‐Ibu in the mixture was performed using the normalization procedure. Linearity was evaluated in the range of 0.68–5.49% R‐Ibu (R\(^{2}\) = 0.999), recovery was found to range between 97 and 103%, the RSD of intra‐ and interday precision below 2.5%, and the limit of quantification for R‐ in S‐Ibu was calculated to be 0.21% (extrapolated) and 0.15% (dilution of racemic ibuprofen), respectively. Isomerization of S‐Ibu was observed under basic conditions by applying long milling times and high milling frequencies.
KW - capillary electrophoresis
KW - chiral separation
KW - Ibuprofen
KW - isomerization
KW - validation
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225852
VL - 42
IS - 17-18
SP - 1790
EP - 1799
ER -
TY - JOUR
A1 - Zahoranová, Anna
A1 - Luxenhofer, Robert
T1 - Poly(2‐oxazoline)‐ and Poly(2‐oxazine)‐Based Self‐Assemblies, Polyplexes, and Drug Nanoformulations—An Update
JF - Advanced Healthcare Materials
N2 - For many decades, poly(2‐oxazoline)s and poly(2‐oxazine)s, two closely related families of polymers, have led the life of a rather obscure research topic with only a few research groups world‐wide working with them. This has changed in the last five to ten years, presumably triggered significantly by very promising clinical trials of the first poly(2‐oxazoline)‐based drug conjugate. The huge chemical and structural toolbox poly(2‐oxazoline)s and poly(2‐oxazine)s has been extended very significantly in the last few years, but their potential still remains largely untapped. Here, specifically, the developments in macromolecular self‐assemblies and non‐covalent drug delivery systems such as polyplexes and drug nanoformulations based on poly(2‐oxazoline)s and poly(2‐oxazine)s are reviewed. This highly dynamic field benefits particularly from the extensive synthetic toolbox poly(2‐oxazoline)s and poly(2‐oxazine)s offer and also may have the largest potential for a further development. It is expected that the research dynamics will remain high in the next few years, particularly as more about the safety and therapeutic potential of poly(2‐oxazoline)s and poly(2‐oxazine)s is learned.
KW - block copolymers
KW - colloids
KW - cytotoxicity
KW - drug delivery
KW - micelles
KW - microphase separation
KW - thermogelling
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225833
VL - 10
IS - 6
ER -
TY - JOUR
A1 - Hojsgaard, Diego
A1 - Schartl, Manfred
T1 - Skipping sex: A nonrecombinant genomic assemblage of complementary reproductive modules
JF - BioEssays
N2 - The unusual occurrence and developmental diversity of asexual eukaryotes remain a puzzle. De novo formation of a functioning asexual genome requires a unique assembly of sets of genes or gene states to disrupt cellular mechanisms of meiosis and gametogenesis, and to affect discrete components of sexuality and produce clonal or hemiclonal offspring. We highlight two usually overlooked but essential conditions to understand the molecular nature of clonal organisms, that is, a nonrecombinant genomic assemblage retaining modifiers of the sexual program, and a complementation between altered reproductive components. These subtle conditions are the basis for physiologically viable and genetically balanced transitions between generations. Genomic and developmental evidence from asexual animals and plants indicates the lack of complementation of molecular changes in the sexual reproductive program is likely the main cause of asexuals' rarity, and can provide an explanatory frame for the developmental diversity and lability of developmental patterns in some asexuals as well as for the discordant time to extinction estimations.
KW - amphimixis
KW - apomixis
KW - automixis
KW - gynogenesis
KW - hybridogenesis
KW - parthenogenesis
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225818
VL - 43
IS - 1
ER -
TY - JOUR
A1 - Budiman, Yudha P.
A1 - Westcott, Stephen A.
A1 - Radius, Udo
A1 - Marder, Todd B.
T1 - Fluorinated Aryl Boronates as Building Blocks in Organic Synthesis
JF - Advanced Synthesis & Catalysis
N2 - Organoboron compounds are well known building blocks for many organic reactions. However, under basic conditions, polyfluorinated aryl boronic acid derivatives suffer from instability issues that are accelerated in compounds containing an ortho‐fluorine group, which result in the formation of the corresponding protodeboronation products. Therefore, a considerable amount of research has focused on novel methodologies to synthesize these valuable compounds while avoiding the protodeboronation issue. This review summarizes the latest developments in the synthesis of fluorinated aryl boronic acid derivatives and their applications in cross‐coupling reactions and other transformations.
image
KW - homogeneous catalysis
KW - boron reagents
KW - boronates
KW - fluorine
KW - fluoroarene
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225908
VL - 363
IS - 9
SP - 2224
EP - 2255
ER -
TY - JOUR
A1 - Ravat, Prince
T1 - Carbo[n]helicenes Restricted to Enantiomerize: An Insight into the Design Process of Configurationally Stable Functional Chiral PAHs
JF - Chemistry – A European Journal
N2 - The most important stereodynamic feature of carbo[n]helicenes is the interconversion of their enantiomers. The Gibbs activation energy (ΔG≠(T)) of this process, which determines the rate of enantiomerization, dictates the configurational stability of [n]helicenes. High values of ΔG≠(T) are required for applications of functional chiral molecules incorporating [n]helicenes or helicene substructures. This minireview provides an overview of the mechanism, recent developments, and factors affecting the enantiomerization of [n]helicenes, which will accelerate the design process of configurationally stable functional chiral molecules based on helicene substructures. Additionally, this minireview addresses the misconception and irregularities in the recent literature on how the terms “racemization” and “enantiomerization” are used as well as how the activation parameters are calculated for [n]helicenes and related compounds.
KW - [n]helicenes
KW - configurational stability
KW - enantiomerization
KW - Gibbs activation energy
KW - racemization
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225871
VL - 27
IS - 12
SP - 3957
EP - 3967
ER -
TY - JOUR
A1 - Sprenger, Philipp P.
A1 - Müsse, Christian
A1 - Hartke, Juliane
A1 - Feldmeyer, Barbara
A1 - Schmitt, Thomas
A1 - Gebauer, Gerhard
A1 - Menzel, Florian
T1 - Dinner with the roommates: trophic niche differentiation and competition in a mutualistic ant‐ant association
JF - Ecological Entomology
N2 - 1. The potential for competition is highest among species in close association. Despite net benefits for both parties, mutualisms can involve costs, including food competition. This might be true for the two neotropical ants Camponotus femoratus and Crematogaster levior, which share the same nest in a presumably mutualistic association (parabiosis).
2. While each nest involves one Crematogaster and one Camponotus partner, both taxa were recently found to comprise two cryptic species that show no partner preferences and seem ecologically similar. Since these cryptic species often occur in close sympatry, they might need to partition their niches to avoid competitive exclusion.
3. Here, we investigated first, is there interference competition between parabiotic Camponotus and Crematogaster, and do they prefer different food sources under competition? And second, is there trophic niche partitioning between the cryptic species of either genus?
4. Using cafeteria experiments, neutral lipid fatty acid and stable isotope analyses, we found evidence for interference competition, but also trophic niche partitioning between Camponotus and Crematogaster. Both preferred protein‐ and carbohydrate‐rich baits, but at protein‐rich baits Ca. femoratus displaced Cr. levior over time, suggesting a potential discovery‐dominance trade‐off between parabiotic partners. Only limited evidence was found for trophic differentiation between the cryptic species of each genus.
5. Although we cannot exclude differentiation in other niche dimensions, we argue that neutral dynamics might mediate the coexistence of cryptic species. This model system is highly suitable for further studies of the maintenance of species diversity and the role of mutualisms in promoting species coexistence.
KW - Cryptic species
KW - Formicidae
KW - neutral theory
KW - niche partitioning
KW - nutrition
KW - parabiosis
KW - species coexistence mechanism
KW - trade‐offs
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228215
VL - 46
IS - 3
SP - 562
EP - 572
ER -
TY - JOUR
A1 - Du, Baoguo
A1 - Ma, Yuhua
A1 - Yáñez‐Serrano, Ana Maria
A1 - Arab, Leila
A1 - Fasbender, Lukas
A1 - Alfarraj, Saleh
A1 - Albasher, Gadah
A1 - Hedrich, Rainer
A1 - White, Philip J.
A1 - Werner, Christiane
A1 - Rennenberg, Heinz
T1 - Physiological responses of date palm (Phoenix dactylifera) seedlings to seawater and flooding
JF - New Phytologist
N2 - In their natural environment along coast lines, date palms are exposed to seawater inundation and, hence, combined stress by salinity and flooding.
To elucidate the consequences of this combined stress on foliar gas exchange and metabolite abundances in leaves and roots, date palm seedlings were exposed to flooding with seawater and its major constituents under controlled conditions.
Seawater flooding significantly reduced CO\(_{2}\) assimilation, transpiration and stomatal conductance, but did not affect isoprene emission. A similar effect was observed upon NaCl exposure. By contrast, flooding with distilled water or MgSO\(_{4}\) did not affect CO\(_{2}\)/H\(_{2}\)O gas exchange or stomatal conductance significantly, indicating that neither flooding itself, nor seawater sulfate, contributed greatly to stomatal closure. Seawater exposure increased Na and Cl contents in leaves and roots, but did not affect sulfate contents significantly. Metabolite analyses revealed reduced abundances of foliar compatible solutes, such as sugars and sugar alcohols, whereas nitrogen compounds accumulated in roots.
Reduced transpiration upon seawater exposure may contribute to controlling the movement of toxic ions to leaves and, therefore, can be seen as a mechanism to cope with salinity. The present results indicate that date palm seedlings are tolerant towards seawater exposure to some extent, and highly tolerant to flooding.
KW - compatible solutes and other metabolites
KW - date palm
KW - flooding
KW - salinity
KW - shoot–root interaction
KW - stomatal conductance
KW - sulfate
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228226
VL - 229
IS - 6
SP - 3318
EP - 3329
ER -
TY - JOUR
A1 - Seibold, Sebastian
A1 - Hothorn, Torsten
A1 - Gossner, Martin M.
A1 - Simons, Nadja K.
A1 - Blüthgen, Nico
A1 - Müller, Jörg
A1 - Ambarlı, Didem
A1 - Ammer, Christian
A1 - Bauhus, Jürgen
A1 - Fischer, Markus
A1 - Habel, Jan C.
A1 - Penone, Caterina
A1 - Schall, Peter
A1 - Schulze, Ernst‐Detlef
A1 - Weisser, Wolfgang W.
T1 - Insights from regional and short‐term biodiversity monitoring datasets are valuable: a reply to Daskalova et al. 2021
JF - Insect Conservation and Diversity
N2 - Reports of major losses in insect biodiversity have stimulated an increasing interest in temporal population changes. Existing datasets are often limited to a small number of study sites, few points in time, a narrow range of land‐use intensities and only some taxonomic groups, or they lack standardised sampling. While new monitoring programs have been initiated, they still cover rather short time periods.
Daskalova et al. 2021 (Insect Conservation and Diversity, 14, 1‐18) argue that temporal trends of insect populations derived from short time series are biased towards extreme trends, while their own analysis of an assembly of shorter‐ and longer‐term time series does not support an overall insect decline. With respect to the results of Seibold et al. 2019 (Nature, 574, 671–674) based on a 10‐year multi‐site time series, they claim that the analysis suffers from not accounting for temporal pseudoreplication.
Here, we explain why the criticism of missing statistical rigour in the analysis of Seibold et al. (2019) is not warranted. Models that include ‘year’ as random effect, as suggested by Daskalova et al. (2021), fail to detect non‐linear trends and assume that consecutive years are independent samples which is questionable for insect time‐series data.
We agree with Daskalova et al. (2021) that the assembly and analysis of larger datasets is urgently needed, but it will take time until such datasets are available. Thus, short‐term datasets are highly valuable, should be extended and analysed continually to provide a more detailed understanding of insect population changes under the influence of global change, and to trigger immediate conservation actions.
KW - Arthropod
KW - biodiversity
KW - insect decline
KW - land use
KW - time series
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228309
VL - 14
IS - 1
SP - 144
EP - 148
ER -
TY - JOUR
A1 - Fehske, Kai
A1 - Berninger, Markus T.
A1 - Alm, Lena
A1 - Hoffmann, Reinhard
A1 - Zellner, Johannes
A1 - Kösters, Clemens
A1 - Barzen, Stefan
A1 - Raschke, Michael J.
A1 - Izadpanah, Kaywan
A1 - Herbst, Elmar
A1 - Domnick, Christoph
A1 - Schüttrumpf, Jan Philipp
A1 - Krause, Matthias
T1 - Aktueller Versorgungsstandard von Patellafrakturen in Deutschland
JF - Der Unfallchirurg
N2 - Hintergrund
Die Versorgung von Patellafrakturen ist technisch anspruchsvoll. Auch wenn die radiologischen Ergebnisse zumeist zufriedenstellend sind, deckt sich dies häufig nicht mit der subjektiven Einschätzung der Patienten. Die klassische Versorgung mittels Drahtzuggurtung weist einige Komplikationen auf. Die winkelstabile Plattenosteosynthese hat sich in den letzten Jahren biomechanisch als vorteilhaft erwiesen.
Fragestellung
Von wem werden Patellafrakturen in Deutschland versorgt? Wie sieht der aktuelle Versorgungsstandard aus? Haben sich „moderne“ Osteosyntheseformen durchgesetzt? Was sind die häufigsten Komplikationen?
Material und Methoden
Die Mitglieder der Deutschen Gesellschaft für Orthopädie und Unfallchirurgie sowie der Deutschen Kniegesellschaft wurden aufgefordert, an einer Onlinebefragung teilzunehmen.
Ergebnisse
Insgesamt wurden 511 komplett ausgefüllte Fragebogen ausgewertet. Die Befragten sind zum größten Teil auf Unfallchirurgie spezialisiert (51,5 %) und verfügen über langjährige Berufserfahrung in Traumazentren. Die Hälfte der Operateure versorgt ≤5 Patellafrakturen jährlich. In knapp 40 % der Fälle wird die präoperative Bildgebung um eine Computertomographie ergänzt. Die klassische Zuggurtung ist noch die bevorzugte Osteosyntheseform bei allen Frakturtypen (Querfraktur 52 %, Mehrfragmentfrakturen 40 %). Bei Mehrfragmentfrakturen entscheiden sich 30 % der Operateure für eine winkelstabile Plattenosteosynthese. Bei Beteiligung des kaudalen Pols dient als zusätzliche Sicherung die McLaughlin-Schlinge (60 %).
Diskussion
Der Versorgungsstandard von Patellafrakturen in Deutschland entspricht weitgehend der aktualisierten S2e-Leitlinie. Nach wie vor wird die klassische Zuggurtungsosteosynthese als Verfahren der Wahl genutzt. Weitere klinische (Langzeit‑)Studien werden benötigt, um die Vorteile der winkelstabilen Plattenosteosynthese zu verifizieren.
N2 - Background
The treatment of patella fractures is technically demanding. Although the radiological results are mostly satisfactory, this often does not correspond to the subjective assessment of the patients. The classical treatment with tension band wiring with K‑wires has several complications. Fixed-angle plate osteosynthesis seems to be biomechanically advantageous.
Objective
Who is treating patella fractures in Germany? What is the current standard of treatment? Have modern forms of osteosynthesis become established? What are the most important complications?
Material and methods
The members of the German Society for Orthopedics and Trauma Surgery and the German Knee Society were asked to participate in an online survey.
Results
A total of 511 completed questionnaires were evaluated. Most of the respondents are specialized in trauma surgery (51.5%), have many years of professional experience and work in trauma centers. Of the surgeons 50% treat ≤5 patella fractures annually. In almost 40% of the cases preoperative imaging is supplemented by computed tomography. The classical tension band wiring with K‑wires is still the preferred form of osteosynthesis for all types of fractures (transverse fractures 52%, comminuted fractures 40%). In the case of comminuted fractures 30% of the surgeons choose fixed-angle plate osteosynthesis. If the inferior pole is involved a McLaughlin cerclage is used for additional protection in 60% of the cases.
Discussion
The standard of care for patella fractures in Germany largely corresponds to the updated S2e guidelines. Tension band wiring is still the treatment of choice. Further (long-term) clinical studies are needed to verify the advantages of fixed-angle plates.
T2 - Current treatment standard for patella fractures in Germany
KW - Kniegelenk
KW - Winkelstabile Platte
KW - Klassische Zuggurtung
KW - Versorgungsstrategien
KW - Umfrage
KW - knee joint
KW - fixed-angle plate
KW - tension band wiring
KW - treatment strategy
KW - survey
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235047
SN - 0177-5537
VL - 124
ER -
TY - JOUR
A1 - Rosenfeldt, Mathias T.
A1 - Hartmann, Elena M.
A1 - Leng, Corinna
A1 - Rosenwald, Andreas
A1 - Anagnostopoulos, Ioannis
T1 - A case of nodular lymphocyte predominant Hodgkin lymphoma with unexpected EBV-latency type
JF - Annals of Hematology
N2 - No abstract available.
KW - nodular lymphcyte
KW - Hodgkin lymphoma
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232571
SN - 0939-5555
VL - 100
ER -
TY - JOUR
A1 - Höhn, Stefan
A1 - Frimmel, Hartwig E.
A1 - Debaille, Vinciane
A1 - Price, Westley
T1 - Pre‐Klondikean oxidation prepared the ground for Broken Hill‐type mineralization in South Africa
JF - Terra Nova
N2 - New Cu isotope data obtained on chalcopyrite from the Black Mountain and the Broken Hill deposits in the medium‐ to high‐grade metamorphic Aggeneys‐Gamsberg ore district (South Africa) require a revision of our understanding of the genesis of metamorphic Broken Hill‐type massive sulphide deposits. Chalcopyrite from both deposits revealed unusually wide ranges in δ\(^{65}\)Cu (−2.41 to 2.84‰ NIST 976 standard) in combination with distinctly positive mean values (0.27 and 0.94‰, respectively). This is interpreted to reflect derivation from various silicate and oxide precursor minerals in which Cu occurred in higher oxidation states. Together with the observation of a typical supergene base metal distribution within the deposits and their spatial association with an unconformity only meters above the ore horizon, our new data are best explained by supergene oxidation of originally possibly SEDEX deposits prior to metamorphic sulphide formation, between the Okiepian (1,210–1,180 Ma) and Klondikean (1,040–1,020 Ma) orogenic events.
KW - South Africa
KW - mineralization
KW - Broken Hill
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218545
VL - 33
IS - 2
SP - 168
EP - 173
ER -
TY - JOUR
A1 - Almeida, R.
A1 - Hristova, S.
A1 - Dashkovskiy, S.
T1 - Uniform bounded input bounded output stability of fractional‐order delay nonlinear systems with input
JF - International Journal of Robust and Nonlinear Control
N2 - The bounded input bounded output (BIBO) stability for a nonlinear Caputo fractional system with time‐varying bounded delay and nonlinear output is studied. Utilizing the Razumikhin method, Lyapunov functions and appropriate fractional derivatives of Lyapunov functions some new bounded input bounded output stability criteria are derived. Also, explicit and independent on the initial time bounds of the output are provided. Uniform BIBO stability and uniform BIBO stability with input threshold are studied. A numerical simulation is carried out to show the system's dynamic response, and demonstrate the effectiveness of our theoretical results.
KW - bounded input bounded output stability
KW - Caputo fractional derivative
KW - Lyapunov functions
KW - Razumikhin method
KW - time‐varying delay
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218554
VL - 31
IS - 1
SP - 225
EP - 249
ER -
TY - JOUR
A1 - Wolf, Matthias
T1 - How to teach about what is a species
JF - Biology
N2 - To ask students what a species is always has something rhetorical about it. Too quickly comes the rote answer, often learned by heart without ever thinking about it: “A species is a reproductive community of populations (reproductively isolated from others), which occupies a specific niche in nature” (Mayr 1982). However, do two people look alike because they are twins or are they twins because they look alike? “Two organisms do not belong to the same species because they mate and reproduce, but they only are able to do so because they belong to the same species” (Mahner and Bunge 1997). Unfortunately, most biology (pre-university) teachers have no opinion on whether species are real or conceptual, simply because they have never been taught the question themselves, but rather one answer they still pass on to their students today, learned by heart without ever thinking about it. Species are either real or conceptual and, in my opinion, it is this “or” that we should teach about. Only then can we discuss those fundamental questions such as who or what is selected, who or what evolves and, finally, what is biodiversity and phylogenetics all about? Individuals related to each other by the tree of life.
KW - biospecies
KW - species as individuals
KW - species as natural kinds
KW - species concept
KW - species problem
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-241052
SN - 2079-7737
VL - 10
IS - 6
ER -
TY - JOUR
A1 - Gerner, Bettina
A1 - Scherf-Clavel, Oliver
T1 - Physiologically based pharmacokinetic modelling of Cabozantinib to simulate enterohepatic recirculation, drug−drug interaction with Rifampin and liver impairment
JF - Pharmaceutics
N2 - Cabozantinib (CAB) is a receptor tyrosine kinase inhibitor approved for the treatment of several cancer types. Enterohepatic recirculation (EHC) of the substance is assumed but has not been further investigated yet. CAB is mainly metabolized via CYP3A4 and is susceptible for drug–drug interactions (DDI). The goal of this work was to develop a physiologically based pharmacokinetic (PBPK) model to investigate EHC, to simulate DDI with Rifampin and to simulate subjects with hepatic impairment. The model was established using PK-Sim® and six human clinical studies. The inclusion of an EHC process into the model led to the most accurate description of the pharmacokinetic behavior of CAB. The model was able to predict plasma concentrations with low bias and good precision. Ninety-seven percent of all simulated plasma concentrations fell within 2-fold of the corresponding concentration observed. Maximum plasma concentration (C\(_{max}\)) and area under the curve (AUC) were predicted correctly (predicted/observed ratio of 0.9–1.2 for AUC and 0.8–1.1 for C\(_{max}\)). DDI with Rifampin led to a reduction in predicted AUC by 77%. Several physiological parameters were adapted to simulate hepatic impairment correctly. This is the first CAB model used to simulate DDI with Rifampin and hepatic impairment including EHC, which can serve as a starting point for further simulations with regard to special populations.
KW - physiologically based pharmacokinetic (PBPK) modeling
KW - Cabozantinib
KW - enterohepatic recirculation
KW - drug–drug interactions (DDIs)
KW - liver impairment
KW - cytochrome P450 3A4 (CYP3A4)
KW - pharmacokinetics
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239661
SN - 1999-4923
VL - 13
IS - 6
ER -
TY - JOUR
A1 - Horder, Hannes
A1 - Guaza Lasheras, Mar
A1 - Grummel, Nadine
A1 - Nadernezhad, Ali
A1 - Herbig, Johannes
A1 - Ergün, Süleyman
A1 - Teßmar, Jörg
A1 - Groll, Jürgen
A1 - Fabry, Ben
A1 - Bauer-Kreisel, Petra
A1 - Blunk, Torsten
T1 - Bioprinting and differentiation of adipose-derived stromal cell spheroids for a 3D breast cancer-adipose tissue model
JF - Cells
N2 - Biofabrication, including printing technologies, has emerged as a powerful approach to the design of disease models, such as in cancer research. In breast cancer, adipose tissue has been acknowledged as an important part of the tumor microenvironment favoring tumor progression. Therefore, in this study, a 3D-printed breast cancer model for facilitating investigations into cancer cell-adipocyte interaction was developed. First, we focused on the printability of human adipose-derived stromal cell (ASC) spheroids in an extrusion-based bioprinting setup and the adipogenic differentiation within printed spheroids into adipose microtissues. The printing process was optimized in terms of spheroid viability and homogeneous spheroid distribution in a hyaluronic acid-based bioink. Adipogenic differentiation after printing was demonstrated by lipid accumulation, expression of adipogenic marker genes, and an adipogenic ECM profile. Subsequently, a breast cancer cell (MDA-MB-231) compartment was printed onto the adipose tissue constructs. After nine days of co-culture, we observed a cancer cell-induced reduction of the lipid content and a remodeling of the ECM within the adipose tissues, with increased fibronectin, collagen I and collagen VI expression. Together, our data demonstrate that 3D-printed breast cancer-adipose tissue models can recapitulate important aspects of the complex cell–cell and cell–matrix interplay within the tumor-stroma microenvironment
KW - adipose-derived stromal cells
KW - adipose tissue
KW - bioprinting
KW - breast cancer model
KW - extracellular matrix
KW - hyaluronic acid
KW - spheroids
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236496
VL - 10
IS - 4
ER -
TY - JOUR
A1 - Wagner, Nicole
A1 - Mott, Kristina
A1 - Upcin, Berin
A1 - Stegner, David
A1 - Schulze, Harald
A1 - Ergün, Süleyman
T1 - CXCL12-abundant reticular (CAR) cells direct megakaryocyte protrusions across the bone marrow sinusoid wall
JF - Cells
N2 - Megakaryocytes (MKs) release platelets into the lumen of bone marrow (BM) sinusoids while remaining to reside within the BM. The morphogenetic events of this complex process are still not fully understood. We combined confocal laser scanning microscopy with transmission and serial block-face scanning electron microscopy followed by 3D-reconstruction on mouse BM tissue sections. These analyses revealed that MKs in close vicinity to BM sinusoid (BMS) wall first induce the lateral retraction of CXCL12-abundant reticular (CAR) cells (CAR), followed by basal lamina (BL) degradation enabling direct MK-sinusoidal endothelial cells (SECs) interaction. Subsequently, an endothelial engulfment starts that contains a large MK protrusion. Then, MK protrusions penetrate the SEC, transmigrate into the BMS lumen and form proplatelets that are in direct contact to the SEC surface. Furthermore, such processes are induced on several sites, as observed by 3D reconstructions. Our data demonstrate that MKs in interaction with CAR-cells actively induce BMS wall alterations, including CAR-cell retraction, BL degradation, and SEC engulfment containing a large MK protrusion. This results in SEC penetration enabling the migration of MK protrusion into the BMS lumen where proplatelets that are adherent to the luminal SEC surface are formed and contribute to platelet release into the blood circulation.
KW - megakaryocytes
KW - microvasculature
KW - CXCL12-abundant reticular (CAR)-cells
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234180
SN - 2073-4409
VL - 10
IS - 4
ER -
TY - JOUR
A1 - Andelovic, Kristina
A1 - Winter, Patrick
A1 - Jakob, Peter Michael
A1 - Bauer, Wolfgang Rudolf
A1 - Herold, Volker
A1 - Zernecke, Alma
T1 - Evaluation of plaque characteristics and inflammation using magnetic resonance imaging
JF - Biomedicines
N2 - Atherosclerosis is an inflammatory disease of large and medium-sized arteries, characterized by the growth of atherosclerotic lesions (plaques). These plaques often develop at inner curvatures of arteries, branchpoints, and bifurcations, where the endothelial wall shear stress is low and oscillatory. In conjunction with other processes such as lipid deposition, biomechanical factors lead to local vascular inflammation and plaque growth. There is also evidence that low and oscillatory shear stress contribute to arterial remodeling, entailing a loss in arterial elasticity and, therefore, an increased pulse-wave velocity. Although altered shear stress profiles, elasticity and inflammation are closely intertwined and critical for plaque growth, preclinical and clinical investigations for atherosclerosis mostly focus on the investigation of one of these parameters only due to the experimental limitations. However, cardiovascular magnetic resonance imaging (MRI) has been demonstrated to be a potent tool which can be used to provide insights into a large range of biological parameters in one experimental session. It enables the evaluation of the dynamic process of atherosclerotic lesion formation without the need for harmful radiation. Flow-sensitive MRI provides the assessment of hemodynamic parameters such as wall shear stress and pulse wave velocity which may replace invasive and radiation-based techniques for imaging of the vascular
function and the characterization of early plaque development. In combination with inflammation imaging, the analyses and correlations of these parameters could not only significantly advance basic preclinical investigations of atherosclerotic lesion formation and progression, but also the diagnostic clinical evaluation for early identification of high-risk plaques, which are prone to rupture. In this review, we summarize the key applications of magnetic resonance imaging for the evaluation of plaque characteristics through flow sensitive and morphological measurements. The simultaneous measurements of functional and structural parameters will further preclinical research on atherosclerosis and has the potential to fundamentally improve the detection of inflammation and vulnerable plaques in patients.
KW - atherosclerosis
KW - mouse models
KW - wall shear stress
KW - pulse wave velocity
KW - arterial elasticity
KW - inflammation
KW - magnetic resonance imaging
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228839
SN - 2227-9059
VL - 9
IS - 2
ER -
TY - JOUR
A1 - Othman, Eman M.
A1 - Fathy, Moustafa
A1 - Bekhit, Amany Abdlrehim
A1 - Abdel-Razik, Abdel-Razik H.
A1 - Jamal, Arshad
A1 - Nazzal, Yousef
A1 - Shams, Shabana
A1 - Dandekar, Thomas
A1 - Naseem, Muhammad
T1 - Modulatory and toxicological perspectives on the effects of the small molecule kinetin
JF - Molecules
N2 - Plant hormones are small regulatory molecules that exert pharmacological actions in mammalian cells such as anti-oxidative and pro-metabolic effects. Kinetin belongs to the group of plant hormones cytokinin and has been associated with modulatory functions in mammalian cells. The mammalian adenosine receptor (A2a-R) is known to modulate multiple physiological responses in animal cells. Here, we describe that kinetin binds to the adenosine receptor (A2a-R) through the Asn253 residue in an adenosine dependent manner. To harness the beneficial effects of kinetin for future human use, we assess its acute toxicity by analyzing different biochemical and histological markers in rats. Kinetin at a dose below 1 mg/kg had no adverse effects on the serum level of glucose or on the activity of serum alanine transaminase (ALT) or aspartate aminotransferase (AST) enzymes in the kinetin treated rats. Whereas, creatinine levels increased after a kinetin treatment at a dose of 0.5 mg/kg. Furthermore, 5 mg/kg treated kinetin rats showed normal renal corpuscles, but a mild degeneration was observed in the renal glomeruli and renal tubules, as well as few degenerated hepatocytes were also observed in the liver. Kinetin doses below 5 mg/kg did not show any localized toxicity in the liver and kidney tissues. In addition to unraveling the binding interaction between kinetin and A2a-R, our findings suggest safe dose limits for the future use of kinetin as a therapeutic and modulatory agent against various pathophysiological conditions.
KW - cytokinin kinetin
KW - modulatory effects
KW - in vivo toxicity
KW - A2a-R receptor
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-223064
SN - 1420-3049
VL - 26
IS - 3
ER -
TY - JOUR
A1 - Yuan, Yijun
A1 - Borrmann, Dorit
A1 - Hou, Jiawei
A1 - Ma, Yuexin
A1 - Nüchter, Andreas
A1 - Schwertfeger, Sören
T1 - Self-Supervised point set local descriptors for Point Cloud Registration
JF - Sensors
N2 - Descriptors play an important role in point cloud registration. The current state-of-the-art resorts to the high regression capability of deep learning. However, recent deep learning-based descriptors require different levels of annotation and selection of patches, which make the model hard to migrate to new scenarios. In this work, we learn local registration descriptors for point clouds
in a self-supervised manner. In each iteration of the training, the input of the network is merely one unlabeled point cloud. Thus, the whole training requires no manual annotation and manual selection of patches. In addition, we propose to involve keypoint sampling into the pipeline, which further improves the performance of our model. Our experiments demonstrate the capability of our self-supervised local descriptor to achieve even better performance than the supervised model, while being easier to train and requiring no data labeling.
KW - point cloud registration
KW - descriptors
KW - self-supervised learning
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-223000
SN - 1424-8220
VL - 21
IS - 2
ER -
TY - JOUR
A1 - Blümig, Gabriele
A1 - Werr, Naoka
T1 - S.P.U.T.N.I.K. – ein Schülertutorial im Sinne des Framework : ein Werkstattbericht
JF - O-Bib. Das Offene Bibliotheksjournal
N2 - Die Arbeitsgruppe Informationskompetenz im Bibliotheksverbund Bayern (AGIK Bay) veröffentlichte im Oktober 2020 das interaktive E-Tutorial S.P.U.T.N.I.K. zur Förderung der Informationskompetenz von Schüler*innen der Oberstufe, das sich inhaltlich am Framework for Information Literacy for Higher Education orientiert. Der Artikel zeichnet die Entstehung des Tutorials in Kooperation mit Studierenden des Fachbereichs Archiv- und Bibliothekswesen der Hochschule für den öffentlichen Dienst in Bayern nach und skizziert die Herausforderungen bei der finalen Umsetzung durch die Universitätsbibliothek Würzburg. Das Tutorial ist als Moodle- und Ilias-kompatibles SCORM-Lernpaket mit vielen interaktiven Quizelementen konzipiert und in fünf Modulen aufgebaut. Es ist online zugänglich und steht zur Nachnutzung innerhalb der DACH-Bibliothekscommunity unter einer Creative Commons Lizenz bereit.
N2 - In October 2020 the Working Group for Information Literacy of the Bavarian Library Network (AGIK Bay) published the interactive e-tutorial S.P.U.T.N.I.K. to promote the information literacy of high school students. Its content is based on the Framework for Information Literacy for Higher Education. The article describes the creation of the tutorial in cooperation with students from the Department of Archive Management and Library Science at the University of Applied Sciences for Public Service in Bavaria and outlines the challenges in the final implementation by the University Library of Würzburg. The tutorial is designed as a Moodle- and Ilias-compatible SCORM learning package with many interactive quiz elements and consists of five independent modules. The tutorial is accessible online and is available for re-use within the German-speaking library community as it has been published under a Creative Commons License.
KW - Framework for Information Literacy for Higher Education
KW - Schwellenkonzepte
KW - Schülertutorial
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-245702
VL - 8
IS - 2
ER -
TY - JOUR
A1 - Blümig, Gabriele
A1 - Klein, Diana
A1 - Wolf, Simone
T1 - Das Framework und die Erstsemesterstudierenden der Medizin : ein Erfahrungsbericht aus der Universitätsbibliothek Würzburg
JF - O-Bib. Das Offene Bibliotheksjournal
N2 - Dieser Artikel schildert die Neukonzeption eines Kurses für Erstsemesterstudierende der Medizin an der Universitätsbibliothek Würzburg unter Einbeziehung des Frameworks for Information Literacy for Higher Education (im Folgenden Framework genannt). Nach einleitenden Bemerkungen zur Theorie der Schwellenkonzepte und zum Framework selbst steht der Kursinhalt mit den dazugehörigen Frames, Knowledge Practices und Dispositions im Fokus. Die Auswertung der Evaluation und ein Ausblick auf die Umsetzung des Kurses in der coronabedingten digitalen Lehre bilden den Schluss.
N2 - This article describes the design of a new one-shot information literacy session for students of medicine in the first semester at the University Library Würzburg. After giving a short introduction into the threshold concept and the theoretical background of the Frameworks for Information Literacy for Higher Education (Framework) we focus on the content of the course in terms of frames, knowledge practices and dispositions. Finally we analyse the evaluation outcomes and show how we transfor-med the session into an e-learning-based course.
KW - Informationskompetenz
KW - Information Literacy
KW - Framework for Information Literacy for Higher Education
KW - Medizinstudium
KW - Erstsemester
KW - Wissenschaftliches Arbeiten
KW - Literaturrecherche
KW - Bibliothekskurs
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-245687
VL - 8
IS - 2
ER -
TY - JOUR
A1 - Ye, Mingyu
A1 - Wilhelm, Martina
A1 - Gentschev, Ivaylo
A1 - Szalay, Aladár
T1 - A modified limiting dilution method for monoclonal stable cell line selection using a real-time fluorescence imaging system: A practical workflow and advanced applications
JF - Methods and Protocols
N2 - Stable cell lines are widely used in laboratory research and pharmaceutical industry. They are mainly applied in recombinant protein and antibody productions, gene function studies, drug screens, toxicity assessments, and for cancer therapy investigation. There are two types of cell lines, polyclonal and monoclonal origin, that differ regarding their homogeneity and heterogeneity. Generating a high-quality stable cell line, which can grow continuously and carry a stable genetic modification without alteration is very important for most studies, because polyclonal cell lines of multicellular origin can be highly variable and unstable and lead to inconclusive experimental results. The most commonly used technologies of single cell originate monoclonal stable cell isolation in laboratory are fluorescence-activated cell sorting (FACS) sorting and limiting dilution cloning. Here, we describe a modified limiting dilution method of monoclonal stable cell line selection using the real-time fluorescence imaging system IncuCyte\(^®\)S3.
KW - monoclonal stable cell
KW - limiting dilution cloning
KW - ncuCyte\(^®\)S3
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228896
VL - 4
IS - 1
ER -
TY - JOUR
A1 - Philipp, Marius
A1 - Dietz, Andreas
A1 - Buchelt, Sebastian
A1 - Kuenzer, Claudia
T1 - Trends in satellite earth observation for permafrost related analyses — A review
JF - Remote Sensing
N2 - Climate change and associated Arctic amplification cause a degradation of permafrost which in turn has major implications for the environment. The potential turnover of frozen ground from a carbon sink to a carbon source, eroding coastlines, landslides, amplified surface deformation and endangerment of human infrastructure are some of the consequences connected with thawing permafrost. Satellite remote sensing is hereby a powerful tool to identify and monitor these features and processes on a spatially explicit, cheap, operational, long-term basis and up to circum-Arctic scale. By filtering after a selection of relevant keywords, a total of 325 articles from 30 international journals published during the last two decades were analyzed based on study location, spatio-
temporal resolution of applied remote sensing data, platform, sensor combination and studied environmental focus for a comprehensive overview of past achievements, current efforts, together with future challenges and opportunities. The temporal development of publication frequency, utilized platforms/sensors and the addressed environmental topic is thereby highlighted. The total
number of publications more than doubled since 2015. Distinct geographical study hot spots were revealed, while at the same time large portions of the continuous permafrost zone are still only sparsely covered by satellite remote sensing investigations. Moreover, studies related to Arctic greenhouse gas emissions in the context of permafrost degradation appear heavily underrepresented.
New tools (e.g., Google Earth Engine (GEE)), methodologies (e.g., deep learning or data fusion etc.)and satellite data (e.g., the Methane Remote Sensing LiDAR Mission (Merlin) and the Sentinel-fleet)will thereby enable future studies to further investigate the distribution of permafrost, its thermal state and its implications on the environment such as thermokarst features and greenhouse gas emission rates on increasingly larger spatial and temporal scales.
KW - satellite remote sensing
KW - permafrost
KW - degradation
KW - thaw
KW - thermokarst
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234198
VL - 13
IS - 6
ER -
TY - JOUR
A1 - Weiß, Martin
A1 - Hein, Grit
A1 - Hewig, Johannes
T1 - Between joy and sympathy: Smiling and sad recipient faces increase prosocial behavior in the dictator game
JF - International Journal of Environmental Research and Public Health
N2 - In human interactions, the facial expression of a bargaining partner may contain relevant information that affects prosocial decisions. We were interested in whether facial expressions of the recipient in the dictator game influence dictators´ ehavior. To test this, we conducted an online study (n = 106) based on a modified version of a dictator game. The dictators allocated money between themselves and another person (recipient), who had no possibility to respond to the dictator.
Importantly, before the allocation decision, the dictator was presented with the facial expression of the recipient (angry, disgusted, sad, smiling, or neutral). The results showed that dictators sent more money to recipients with sad or smiling facial expressions and less to recipients with angry or disgusted facial expressions compared with a neutral facial expression. Moreover, based on the sequential analysis of the decision and the interaction partner in the preceding trial, we found that decision-making depends upon previous interactions.
KW - emotional influence
KW - dictator game
KW - facial expression
KW - social decision-making
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-241106
VL - 18
IS - 11
ER -
TY - JOUR
A1 - Upcin, Berin
A1 - Henke, Erik
A1 - Kleefeldt, Florian
A1 - Hoffmann, Helene
A1 - Rosenwald, Andreas
A1 - Irmak-Sav, Ster
A1 - Aktas, Huseyin Bertal
A1 - Rückschloß, Uwe
A1 - Ergün, Süleyman
T1 - Contribution of adventitia-derived stem and progenitor cells to new vessel formation in tumors
JF - Cells
N2 - Blocking tumor vascularization has not yet come to fruition to the extent it was hoped for, as angiogenesis inhibitors have shown only partial success in the clinic. We hypothesized that under- appreciated vascular wall-resident stem and progenitor cells (VW-SPCs) might be involved in tumor vascularization and influence effectiveness of anti-angiogenic therapy. Indeed, in patient samples, we observed that vascular adventitia-resident CD34\(^+\) VW-SPCs are recruited to tumors in situ from co-opted vessels. To elucidate this in detail, we established an ex vivo model using concomitant embedding of multi-cellular tumor spheroids (MCTS) and mouse aortic rings (ARs) into collagen
gels, similar to the so-called aortic ring assay (ARA). Moreover, ARA was modified by removing the ARs’ adventitia that harbors VW-SPCs. Thus, this model enabled distinguishing the contribution of VW-SPCs from that of mature endothelial cells (ECs) to new vessel formation. Our results show that the formation of capillary-like sprouts is considerably delayed, and their number and network formation were significantly reduced by removing the adventitia. Substituting iPSC-derived neural spheroids for MCTS resulted in distinct sprouting patterns that were also strongly influenced by the
presence or absence of VW-SPCs, also underlying the involvement of these cells in non-pathological vascularization. Our data suggest that more comprehensive approaches are needed in order to block all of the mechanisms contributing to tumor vascularization.
KW - vascularization model
KW - tumor spheroids
KW - vascular wall stem and progenitor cells
KW - aortic adventitia
KW - vasculogenesis
KW - tumor-vessel wall-interface model
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242577
VL - 10
IS - 7
ER -
TY - JOUR
A1 - Drenckhahn, Detlev
T1 - Zur Vegetation der Seedeiche der Nordseeküste Schleswig-Holsteins − Implikationen für die Umsetzung des Generalplans Küstenschutz
T1 - On the vegetation of the sea dikes of the North Sea coast of Schleswig-Holstein − Implications for the implementation of the General Plan for Coastal Protection
JF - Forum Geobotanicum
N2 - Bis zum Jahr 2100 prognostiziert der Weltklimarat (IPCC 2021) einen Anstieg des Meeresspiegels von bis zu 63-101 cm gegenüber heutigen Wasserständen. Im Rahmen des Generalplans Küstenschutz Schleswig-Holstein(GKSH) soll als Klimafolgeanpassung eine Erhöhung und Profiländerung der meisten Nordseedeiche und Elbedeiche erfolgen (zusammen 363,3 km mit einer Vegetationsfläche von 3.500 ha). Diese Maßnahmen werden mit einem vollständigen Verlust der alten Deichvegetation einhergehen und zur Freisetzung von großen Mengen an CO₂ aus dem Bodenkohlenstoff führen. Die Seedeiche der Nordseeküste (262 km) zählen zu den artenreichen, semi-natürlichen und von Schafen beweideten Grasländern (Fläche von 2600 ha) in Schleswig-Holstein mit bis zu 18 Gras- und 64 zweikeim-blättrigen Blütenpflanzen und an die Vegetation gebundene 800-1000 Arten von Invertebraten (darunter 200 Käferarten). Auf die Außenböschung dringen Pflanzen der Salzwiesengesellschaften vor. Die steileren, wärmeexponierten (überwiegend nach Osten und Süden ausgerichtet) und durch Vertritt lückigen Innenböschungen der Seedeiche sind wertvolle Refugien wärmeliebender, konkurrenzschwacher Arten von Magerstandorten und Trittgesellschaften wie die folgenden mediterran-subatlantischen Arten: Knotenklettenkerbel (Torilis nodosa), Zwergklee/Armblütiger Klee (Trifolium micranthum) und Vogelfußklee (Trifolium ornithopodioides). Für die Erhaltung beider Kleearten (die aktuelle Verbreitung wird dokumentiert) besitzt Schleswig-Holstein eine nationale und nordwest-europäisch-kontinentale Verantwortlichkeit. Folgende Maßnahmen zum Schutz der reichhaltigen Deichvegetation und Teilen seiner Invertebratenfauna bei der Deichverstärkung im Rahmen des GKSH werden vorgeschlagen: 1. Abheben der Grasnarbe mit Wurzelraum und zeitnahe Wiederverlegung der alten Grasnarbe (Soden) auf das neue Deichprofil; das ist auch wichtig zum Erhalt des Bodenkohlenstoffs (Klimaschutz). 2. Einsaat von neuen Deichprofilen mit Saatgut von artenreichen Deichabschnitten. 3. Aufnahme substanzieller Forschungsprogramme/Forschungsförderung zur Ökologie der Seedeiche. Weiterhin sollte auf den Einsatz von Herbiziden auf Deichen zur Bekämpfung von Disteln verzichtet werden.
N2 - Climate change is expected by the Intergovernmental Panel of Climate Change (IPCC 2021) to cause a rise in the sea level of up to 63-101 cm by 2100. The general plan for coastal protection in Schleswig-Holstein (GKSH) is to increase in the height of most of the North Sea-dikes and dikes of River Elbe (together 363.3 km with a vegetation cover of ca. 3,500 ha). These actions will be accompanied by a complete loss of old dike vegetation and will result in the release of large amounts of CO₂ from soil carbon. The sea dikes of the North Sea coast (262 km) are covered by a diverse semi-natural grassland (area of 2,600 ha) grazed by sheep and comprising up to 18 grass species, 64 dicotyledonous flowering plant species and 800-1000 invertebrate species (among them 200 beetle species). Plants of the salt marsh communities invade the vegetation on the lower outer slopes. The steeper, warmer, drier and wind-protected inner slopes of the sea dikes (oriented mainly to the East and South) contain frequent ground injuries (by sheep claws) and are preferentially settled by thermophilic and less competitive species such as the following Mediterranean-Subatlantic plants: Knotted hedgeparsley (Torilis nodosa), the rare Slender trefoil (Trifolium micranthum) and Bird's-foot clover (Trifolium ornithopodioides) (only natural sites in Germany, red list categories 1 and 2). Schleswig-Holstein has a great responsibility for the survival of these clover species at their continental North-Western boundary (the current distribution is documented). The following measures are proposed to protect the rich dike vegetation and parts of their invertebrate fauna during dike strengthening within the GKSH: 1. lifting of the turf with root space and re-laying of the old turf (sods) on the new dike profile which is also important for protection of soil carbon storage (climate protection). 2. Seeding of new dike profiles with seeds from species-rich dike sections. 3. Inclusion of substantial research programs/funding on the ecology of sea dikes. Furthermore, the use of herbicides on dikes to control thistles should be avoided.
KW - Sea dikes
KW - biodiversity
KW - climate
KW - Trifolium micranthum
KW - Trifolium ornithopodioides
KW - Seedeich
KW - Vegetation
KW - Küstenschutz
KW - Schleswig-Holstein
KW - Biodiversität
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-243795
UR - http://www.forum-geobotanicum.net/articles/vol_10-2021/drenckhahn_seedeiche/FG---drenckhahn_vegetation_der_seedeiche.pdf
SN - 1867-9315
VL - 10
ER -
TY - JOUR
A1 - Pfister, Robert
A1 - Klaffehn, Annika L.
A1 - Kalckert, Andreas
A1 - Kunde, Winfried
A1 - Dignath, David
T1 - How to lose a hand: Sensory updating drives disembodiment
JF - Psychonomic Bulletin & Review
N2 - Body representations are readily expanded based on sensorimotor experience. A dynamic view of body representations, however, holds that these representations cannot only be expanded but that they can also be narrowed down by disembodying elements of the body representation that are no longer warranted. Here we induced illusory ownership in terms of a moving rubber hand illusion and studied the maintenance of this illusion across different conditions. We observed ownership experience to decrease gradually unless participants continued to receive confirmatory multisensory input. Moreover, a single instance of multisensory mismatch – a hammer striking the rubber hand but not the real hand – triggered substantial and immediate disembodiment. Together, these findings support and extend previous theoretical efforts to model body representations through basic mechanisms of multisensory integration. They further support an updating model suggesting that embodied entities fade from the body representation if they are not refreshed continuously.
KW - body representation
KW - embodiment
KW - disembodiment
KW - moving rubber-hand illusion
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235195
SN - 1069-9384
VL - 28
ER -
TY - JOUR
A1 - Muth, Felicitas V.
A1 - Wirth, Robert
A1 - Kunde, Winfried
T1 - Temporal binding past the Libet clock: testing design factors for an auditory timer
JF - Behavior Research Methods
N2 - Voluntary actions and causally linked sensory stimuli are perceived to be shifted towards each other in time. This so-called temporal binding is commonly assessed in paradigms using the Libet Clock. In such experiments, participants have to estimate the timing of actions performed or ensuing sensory stimuli (usually tones) by means of a rotating clock hand presented on a screen. The aforementioned task setup is however ill-suited for many conceivable setups, especially when they involve visual effects. To address this shortcoming, the line of research presented here establishes an alternative measure for temporal binding by using a sequence of timed sounds. This method uses an auditory timer, a sequence of letters presented during task execution, which serve as anchors for temporal judgments. In four experiments, we manipulated four design factors of this auditory timer, namely interval length, interval filling, sequence predictability, and sequence length, to determine the most effective and economic method for measuring temporal binding with an auditory timer.
KW - temporal binding
KW - auditory timer
KW - experimental design
KW - measures
KW - intentional binding
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234922
VL - 53
IS - 3
ER -
TY - JOUR
A1 - Hock, Michael
A1 - Terekhov, Maxim
A1 - Stefanescu, Maria Roxana
A1 - Lohr, David
A1 - Herz, Stefan
A1 - Reiter, Theresa
A1 - Ankenbrand, Markus
A1 - Kosmala, Aleksander
A1 - Gassenmaier, Tobias
A1 - Juchem, Christoph
A1 - Schreiber, Laura Maria
T1 - B\(_{0}\) shimming of the human heart at 7T
JF - Magnetic Resonance in Medicine
N2 - Purpose
Inhomogeneities of the static magnetic B\(_{0}\) field are a major limiting factor in cardiac MRI at ultrahigh field (≥ 7T), as they result in signal loss and image distortions. Different magnetic susceptibilities of the myocardium and surrounding tissue in combination with cardiac motion lead to strong spatio‐temporal B\(_{0}\)‐field inhomogeneities, and their homogenization (B0 shimming) is a prerequisite. Limitations of state‐of‐the‐art shimming are described, regional B\(_{0}\) variations are measured, and a methodology for spherical harmonics shimming of the B\(_{0}\) field within the human myocardium is proposed.
Methods
The spatial B\(_{0}\)‐field distribution in the heart was analyzed as well as temporal B\(_{0}\)‐field variations in the myocardium over the cardiac cycle. Different shim region‐of‐interest selections were compared, and hardware limitations of spherical harmonics B\(_{0}\) shimming were evaluated by calibration‐based B0‐field modeling. The role of third‐order spherical harmonics terms was analyzed as well as potential benefits from cardiac phase–specific shimming.
Results
The strongest B\(_{0}\)‐field inhomogeneities were observed in localized spots within the left‐ventricular and right‐ventricular myocardium and varied between systolic and diastolic cardiac phases. An anatomy‐driven shim region‐of‐interest selection allowed for improved B\(_{0}\)‐field homogeneity compared with a standard shim region‐of‐interest cuboid. Third‐order spherical harmonics terms were demonstrated to be beneficial for shimming of these myocardial B\(_{0}\)‐field inhomogeneities. Initial results from the in vivo implementation of a potential shim strategy were obtained. Simulated cardiac phase–specific shimming was performed, and a shim term‐by‐term analysis revealed periodic variations of required currents.
Conclusion
Challenges in state‐of‐the‐art B\(_{0}\) shimming of the human heart at 7 T were described. Cardiac phase–specific shimming strategies were found to be superior to vendor‐supplied shimming.
KW - 7 T
KW - B
KW - cardiac MRI
KW - shimming
KW - ultrahigh field
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218096
VL - 85
IS - 1
SP - 182
EP - 196
ER -
TY - JOUR
A1 - Homburg, Annika
A1 - Weiß, Christian H.
A1 - Alwan, Layth C.
A1 - Frahm, Gabriel
A1 - Göb, Rainer
T1 - A performance analysis of prediction intervals for count time series
JF - Journal of Forecasting
N2 - One of the major motivations for the analysis and modeling of time series data is the forecasting of future outcomes. The use of interval forecasts instead of point forecasts allows us to incorporate the apparent forecast uncertainty. When forecasting count time series, one also has to account for the discreteness of the range, which is done by using coherent prediction intervals (PIs) relying on a count model. We provide a comprehensive performance analysis of coherent PIs for diverse types of count processes. We also compare them to approximate PIs that are computed based on a Gaussian approximation. Our analyses rely on an extensive simulation study. It turns out that the Gaussian approximations do considerably worse than the coherent PIs. Furthermore, special characteristics such as overdispersion, zero inflation, or trend clearly affect the PIs' performance. We conclude by presenting two empirical applications of PIs for count time series: the demand for blood bags in a hospital and the number of company liquidations in Germany.
KW - coherent forecasting
KW - count time series
KW - estimation error
KW - Gaussian approximation
KW - prediction interval
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-217906
VL - 40
IS - 4
SP - 603
EP - 609
ER -
TY - JOUR
A1 - Vogel, Sebastian
A1 - Bussler, Heinz
A1 - Finnberg, Sven
A1 - Müller, Jörg
A1 - Stengel, Elisa
A1 - Thorn, Simon
T1 - Diversity and conservation of saproxylic beetles in 42 European tree species: an experimental approach using early successional stages of branches
JF - Insect Conservation and Diversity
N2 - Tree species diversity is important to maintain saproxylic beetle diversity in managed forests. Yet, knowledge about the conservational importance of single tree species and implications for forest management and conservation practices are lacking.
We exposed freshly cut branch‐bundles of 42 tree species, representing tree species native and non‐native to Europe, under sun‐exposed and shaded conditions for 1 year. Afterwards, communities of saproxylic beetles were reared ex situ for 2 years. We tested for the impact of tree species and sun exposure on alpha‐, beta‐, and gamma‐diversity as well as composition of saproxylic beetle communities. Furthermore, the number of colonised tree species by each saproxylic beetle species was determined.
Tree species had a lower impact on saproxylic beetle communities compared to sun exposure. The diversity of saproxylic beetles varied strongly among tree species, with highest alpha‐ and gamma‐diversity found in Quercus petraea. Red‐listed saproxylic beetle species occurred ubiquitously among tree species. We found distinct differences in the community composition of broadleaved and coniferous tree species, native and non‐native tree species as well as sun‐exposed and shaded deadwood.
Our study enhances the understanding of the importance of previously understudied and non‐native tree species for the diversity of saproxylic beetles. To improve conservation practices for saproxylic beetles and especially red‐listed species, we suggest a stronger incorporation of tree species diversity and sun exposure of into forest management strategies, including the enrichment of deadwood from native and with a specific focus on locally rare or silviculturally less important tree species.
KW - deadwood
KW - deadwood enrichment
KW - decay
KW - forest management
KW - host specificity
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218401
VL - 14
IS - 1
SP - 132
EP - 143
ER -
TY - JOUR
A1 - Scheiner, Matthias
A1 - Sink, Alexandra
A1 - Spatz, Philipp
A1 - Endres, Erik
A1 - Decker, Michael
T1 - Photopharmacology on Acetylcholinesterase: Novel Photoswitchable Inhibitors with Improved Pharmacological Profiles
JF - ChemPhotoChem
N2 - Considerable effort has previously been invested in a light‐controlled inhibition of the enzyme acetylcholinesterase (AChE). We found that a novel azobenzene‐based bistacrine AChE inhibitor switched faster than the known dithienylethene based bistacrine and inverted the photo‐controlled interactions of the photoisomers compared to its dithienylethene congener. Furthermore, we have optimized a previously described light‐controlled tacrine‐based AChE inhibitor. Isomerization upon irradiation with UV light of the novel inhibitor was observed in aqueous medium and showed no fatigue over several cycles. The cis‐enriched form showed an 8.4‐fold higher inhibition of hAChE compared with its trans‐enriched form and was about 30‐fold more active than the reference compound tacrine with a single‐digit nanomolar inhibition. We went beyond proof‐of‐concept to discover photoswitchable AChE inhibitors with pharmacologically desirable nanomolar inhibition, “cis‐on” effect, and pronounces differences between the photoisomers.
KW - azobenzenes
KW - enzymes
KW - kinetics
KW - photopharmacology
KW - tacrine
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218445
VL - 5
IS - 2
SP - 149
EP - 159
ER -
TY - JOUR
A1 - Weinelt, Nadine
A1 - Karathanasis, Christos
A1 - Smith, Sonja
A1 - Medler, Juliane
A1 - Malkusch, Sebastian
A1 - Fulda, Simone
A1 - Wajant, Harald
A1 - Heilemann, Mike
A1 - van Wijk, Sjoerd J. L.
T1 - Quantitative single‐molecule imaging of TNFR1 reveals zafirlukast as antagonist of TNFR1 clustering and TNFα‐induced NF‐ĸB signaling
JF - Journal of Leukocyte Biology
N2 - TNFR1 is a crucial regulator of NF‐ĸB‐mediated proinflammatory cell survival responses and programmed cell death (PCD). Deregulation of TNFα‐ and TNFR1‐controlled NF‐ĸB signaling underlies major diseases, like cancer, inflammation, and autoimmune diseases. Therefore, although being routinely used, antagonists of TNFα might also affect TNFR2‐mediated processes, so that alternative approaches to directly antagonize TNFR1 are beneficial. Here, we apply quantitative single‐molecule localization microscopy (SMLM) of TNFR1 in physiologic cellular settings to validate and characterize TNFR1 inhibitory substances, exemplified by the recently described TNFR1 antagonist zafirlukast. Treatment of TNFR1‐mEos2 reconstituted TNFR1/2 knockout mouse embryonic fibroblasts (MEFs) with zafirlukast inhibited both ligand‐independent preligand assembly domain (PLAD)‐mediated TNFR1 dimerization as well as TNFα‐induced TNFR1 oligomerization. In addition, zafirlukast‐mediated inhibition of TNFR1 clustering was accompanied by deregulation of acute and prolonged NF‐ĸB signaling in reconstituted TNFR1‐mEos2 MEFs and human cervical carcinoma cells. These findings reveal the necessity of PLAD‐mediated, ligand‐independent TNFR1 dimerization for NF‐ĸB activation, highlight the PLAD as central regulator of TNFα‐induced TNFR1 oligomerization, and demonstrate that TNFR1‐mEos2 MEFs can be used to investigate TNFR1‐antagonizing compounds employing single‐molecule quantification and functional NF‐ĸB assays at physiologic conditions.
KW - Single‐Molecule Localization Microscopy (SMLM)
KW - Pre‐Ligand Assembly Domain (PLAD)
KW - Cysteine‐Rich Domain (CRD)
KW - CysLTR1
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-215960
VL - 109
IS - 2
SP - 363
EP - 371
ER -
TY - JOUR
A1 - Rubo, Marius
A1 - Gamer, Matthias
T1 - Stronger reactivity to social gaze in virtual reality compared to a classical laboratory environment
JF - British Journal of Psychology
N2 - People show a robust tendency to gaze at other human beings when viewing images or videos, but were also found to relatively avoid gaze at others in several real‐world situations. This discrepancy, along with theoretical considerations, spawned doubts about the appropriateness of classical laboratory‐based experimental paradigms in social attention research. Several researchers instead suggested the use of immersive virtual scenarios in eliciting and measuring naturalistic attentional patterns, but the field, struggling with methodological challenges, still needs to establish the advantages of this approach. Here, we show using eye‐tracking in a complex social scenario displayed in virtual reality that participants show enhanced attention towards the face of an avatar at near distance and demonstrate an increased reactivity towards her social gaze as compared to participants who viewed the same scene on a computer monitor. The present study suggests that reactive virtual agents observed in immersive virtual reality can elicit natural modes of information processing and can help to conduct ecologically more valid experiments while maintaining high experimental control.
KW - reactive virtual agents
KW - social attention
KW - social gaze
KW - virtual reality
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-215972
VL - 112
IS - 1
SP - 301
EP - 314
ER -
TY - JOUR
A1 - Kouhestani, Dina
A1 - Geis, Maria
A1 - Alsouri, Saed
A1 - Bumm, Thomas G. P.
A1 - Einsele, Hermann
A1 - Sauer, Markus
A1 - Stuhler, Gernot
T1 - Variant signaling topology at the cancer cell–T-cell interface induced by a two-component T-cell engager
JF - Cellular & Molecular Immunology
N2 - No abstract available.
KW - immunotherapy
KW - tumour immunology
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-241189
VL - 18
ER -
TY - JOUR
A1 - Atiyas, Izak
A1 - Doganoglu, Toker
A1 - Inceoglu, Firat
T1 - Upstream Competition with Complex and Unobservable Contracts
JF - Review of Industrial Organization
N2 - This paper examines situations where two vertically integrated firms consider supplying an input to an independent downstream competitor via privately observed contracts. We identify equilibria where competition in the upstream market emerges—the downstream competitor gets supplied—as well as when the downstream firm does not receive the input and is excluded from the market. The likelihood of the outcome in which the downstream firm does not get supplied depends not only on demand parameters, but also on contractual flexibility and observability. We show that when contracts are unobservable, downstream entry will occur less often. Furthermore, our results suggest that permitting contracts that enable the contracting parties to coordinate their behavior in the downstream market may improve welfare by increasing the likelihood that the downstream firm is supplied.
KW - collective refusal to supply
KW - foreclosure
KW - unobservable contracts
KW - upstream competition
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-241161
VL - 58
ER -