@article{OPUS4-31268, title = {Search for new phenomena in events with same-charge leptons and b-jets in pp collisions at √\(s\) = 13 TeV with the ATLAS detector}, series = {Journal of High Energy Physics}, volume = {12}, journal = {Journal of High Energy Physics}, number = {39}, organization = {The ATLAS Collaboration}, doi = {10.1007/JHEP12(2018)039}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-312681}, pages = {1-55}, year = {2018}, abstract = {A search for new phenomena in events with two same- charge leptons or three leptons and jets identi fi ed as originating from b - quarks in a data sample of 36.1 fb of pp collisions at ps = 13TeV recorded by the ATLAS detector at the Large Hadron Collider is reported. No signi fi cant excess is found and limits are set on vector- like quark, fourtop- quark, and same- sign top- quark pair production. The observed ( expected) 95\% CL mass limits for a vector- like T - and B - quark singlet are mT > 0 : 98 ( 0 : 99) TeV and mB > 1 : 00 ( 1 : 01) TeV respectively. Limits on the production of the vector- like T5=3 - quark are also derived considering both pair and single production; in the former case the lower limit on the mass of the T5=3 - quark is ( expected to be) 1.19 ( 1.21) TeV. The Standard Model fourtop- quark production cross- section upper limit is ( expected to be) 69 ( 29) fb. Constraints are also set on exotic four- top- quark production models. Finally, limits are set on samesign top- quark pair production. The upper limit on uu ! tt production is ( expected to be) 89 ( 59) fb for a mediator mass of 1TeV, and a dark- matter interpretation is also derived, excluding a mediator of 3TeV with a dark- sector coupling of 1.0 and a coupling to ordinary matter above 0.31.}, language = {en} } @article{WeissZieglerFliesseretal.2018, author = {Weiss, Esther and Ziegler, Sabrina and Fliesser, Mirjam and Schmitt, Anna-Lena and H{\"u}nniger, Kerstin and Kurzai, Oliver and Morton, Charles-Oliver and Einsele, Hermann and Loeffler, Juergen}, title = {First Insights in NK—DC Cross-Talk and the Importance of Soluble Factors During Infection With Aspergillus fumigatus}, series = {Frontiers in Cellular and Infection Microbiology}, volume = {8}, journal = {Frontiers in Cellular and Infection Microbiology}, doi = {10.3389/fcimb.2018.00288}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-233565}, year = {2018}, abstract = {Invasive aspergillosis (IA) is an infectious disease caused by the fungal pathogen Aspergillus fumigatus that mainly affects immunocompromised hosts. To investigate immune cell cross-talk during infection with A. fumigatus, we co-cultured natural killer (NK) cells and dendritic cells (DC) after stimulation with whole fungal structures, components of the fungal cell wall, fungal lysate or ligands for distinct fungal receptors. Both cell types showed activation after stimulation with fungal components and were able to transfer activation signals to the counterpart not stimulated cell type. Interestingly, DCs recognized a broader spectrum of fungal components and thereby initiated NK cell activation when those did not recognize fungal structures. These experiments highlighted the supportive function of DCs in NK cell activation. Furthermore, we focused on soluble DC mediated NK cell activation and showed that DCs stimulated with the TLR2/Dectin-1 ligand zymosan could maximally stimulate the expression of CD69 on NK cells. Thus, we investigated the influence of both receptors for zymosan, Dectin-1 and TLR2, which are highly expressed on DCs but show only minimal expression on NK cells. Specific focus was laid on the question whether Dectin-1 or TLR2 signaling in DCs is important for the secretion of soluble factors leading to NK cell activation. Our results show that Dectin-1 and TLR2 are negligible for NK cell activation. We conclude that besides Dectin-1 and TLR2 other receptors on DCs are able to compensate for the missing signal.}, language = {en} } @article{VuralDopplerMeinl2018, author = {Vural, Atay and Doppler, Kathrin and Meinl, Edgar}, title = {Autoantibodies Against the Node of Ranvier in Seropositive Chronic Inflammatory Demyelinating Polyneuropathy: Diagnostic, Pathogenic, and Therapeutic Relevance}, series = {Frontiers in Immunology}, volume = {9}, journal = {Frontiers in Immunology}, doi = {10.3389/fimmu.2018.01029}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-233279}, year = {2018}, abstract = {Discovery of disease-associated autoantibodies has transformed the clinical management of a variety of neurological disorders. Detection of autoantibodies aids diagnosis and allows patient stratification resulting in treatment optimization. In the last years, a set of autoantibodies against proteins located at the node of Ranvier has been identified in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). These antibodies target neurofascin, contactin1, or contactin-associated protein 1, and we propose to name CIDP patients with these antibodies collectively as seropositive. They have unique clinical characteristics that differ from seronegative CIDP. Moreover, there is compelling evidence that autoantibodies are relevant for the pathogenesis. In this article, we review the current knowledge on the characteristics of autoantibodies against the node of Ranvier proteins and their clinical relevance in CIDP. We start with a description of the structure of the node of Ranvier followed by a summary of assays used to identify seropositive patients; and then, we describe clinical features and characteristics linked to seropositivity. We review knowledge on the role of these autoantibodies for the pathogenesis with relevance for the emerging concept of nodopathy/paranodopathy and summarize the treatment implications.}, language = {en} } @article{VaahtorantaLenhartSuggateetal.2019, author = {Vaahtoranta, Enni and Lenhart, Jan and Suggate, Sebastian and Lenhard, Wolfgang}, title = {Interactive Elaborative Storytelling: Engaging Children as Storytellers to Foster Vocabulary}, series = {Frontiers in Psychology}, volume = {10}, journal = {Frontiers in Psychology}, doi = {10.3389/fpsyg.2019.01534}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-232136}, year = {2019}, abstract = {Positive effects of shared reading for children's language development are boosted by including instruction of word meanings and by increasing interactivity. The effects of engaging children as storytellers on vocabulary development have been less well studied. We developed an approach termed Interactive Elaborative Storytelling (IES), which employs both word-learning techniques and children's storytelling in a shared-reading setting. To systematically investigate potential benefits of children as storytellers, we contrasted this approach to two experimental groups, an Elaborative Storytelling group employing word-learning techniques but no storytelling by children and a Read-Aloud group, excluding any additional techniques. The study was a 3 × 2 pre-posttest randomized design with 126 preschoolers spanning 1 week. Measured outcomes were receptive and expressive target vocabulary, story memory, and children's behavior during story sessions. All three experimental groups made comparable gains on target words from pre- to posttest and there was no difference between groups in story memory. However, in the Elaborative Storytelling group, children were the least restless. Findings are discussed in terms of their contribution to optimizing shared reading as a method of fostering language.}, language = {en} } @article{TreffWinkertSarebanetal.2019, author = {Treff, Gunnar and Winkert, Kay and Sareban, Mahdi and Steinacker, J{\"u}rgen M. and Sperlich, Billy}, title = {The Polarization-Index: A Simple Calculation to Distinguish Polarized From Non-polarized Training Intensity Distributions}, series = {Frontiers in Physiology}, volume = {10}, journal = {Frontiers in Physiology}, doi = {10.3389/fphys.2019.00707}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229040}, year = {2019}, abstract = {The training intensity distribution (TID) of endurance athletes has retrieved substantial scientific interest since it reflects a vital component of training prescription: (i) the intensity of exercise and its distribution over time are essential components for adaptation to endurance training and (ii) the training volume (at least for most endurance disciplines) is already near or at maximum, so optimization of training procedures including TID have become paramount for success. This paper aims to elaborate the polarization-index (PI) which is calculated as log10(Zone 1/Zone 2∗Zone 3∗100), where Zones 1-3 refer to aggregated volume (time or distance) spent with low, mid, or high intensity training. PI allows to distinguish between non-polarized and polarized TID using a cut-off > 2.00 a.U. and to quantify the level of a polarized TID. Within this hypothesis paper, examples from the literature illustrating the usefulness of PI-calculation are discussed as well as its limitations. Further it is elucidated how the PI may contribute to a more precise definition of TID descriptors.}, language = {en} } @article{TooKellerSickeletal.2018, author = {Too, Chin Chin and Keller, Alexander and Sickel, Wiebke and Lee, Sui Mae and Yule, Catherine M.}, title = {Microbial Community Structure in a Malaysian Tropical Peat Swamp Forest: The Influence of Tree Species and Depth}, series = {Frontiers in Microbiology}, volume = {9}, journal = {Frontiers in Microbiology}, doi = {10.3389/fmicb.2018.02859}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229000}, year = {2018}, abstract = {Tropical peat swamp forests sequester globally significant stores of carbon in deep layers of waterlogged, anoxic, acidic and nutrient-depleted peat. The roles of microbes in supporting these forests through the formation of peat, carbon sequestration and nutrient cycling are virtually unknown. This study investigated physicochemical peat properties and microbial diversity between three dominant tree species: Shorea uliginosa (Dipterocarpaceae), Koompassia malaccensis (legumes associated with nitrogen-fixing bacteria), Eleiodoxa conferta (palm) and depths (surface, 45 and 90 cm) using microbial 16S rRNA gene amplicon sequencing. Water pH, oxygen, nitrogen, phosphorus, total phenolic contents and C/N ratio differed significantly between depths, but not tree species. Depth also strongly influenced microbial diversity and composition, while both depth and tree species exhibited significant impact on the archaeal communities. Microbial diversity was highest at the surface, where fresh leaf litter accumulates, and nutrient supply is guaranteed. Nitrogen was the core parameter correlating to microbial communities, but the interactive effects from various environmental variables displayed significant correlation to relative abundance of major microbial groups. Proteobacteria was the dominant phylum and the most abundant genus, Rhodoplanes, might be involved in nitrogen fixation. The most abundant methanogens and methanotrophs affiliated, respectively, to families Methanomassiliicoccaceae and Methylocystaceae. Our results demonstrated diverse microbial communities and provide valuable insights on microbial ecology in these extreme ecosystems.}, language = {en} } @article{TichaMoosWajantetal.2018, author = {Ticha, Olga and Moos, Lukas and Wajant, Harald and Bekeredjian-Ding, Isabelle}, title = {Expression of Tumor Necrosis Factor Receptor 2 Characterizes TLR9-Driven Formation of Interleukin-10-Producing B Cells}, series = {Frontiers in Immunology}, volume = {8}, journal = {Frontiers in Immunology}, doi = {10.3389/fimmu.2017.01951}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241323}, year = {2018}, abstract = {B cell-derived interleukin-10 (IL-10) production has been described as a hallmark for regulatory function in B lymphocytes. However, there is an ongoing debate on the origin of IL-10-secreting B cells and lack of specific surface markers has turned into an important obstacle for studying human B regulatory cells. In this study, we propose that tumor necrosis factor receptor 2 (TNFR2) expression can be used for enrichment of IL-10-secreting B cells. Our data confirm that IL-10 production can be induced by TLR9 stimulation with CpG ODN and that IL-10 secretion accompanies differentiation of peripheral blood B cells into plasma blasts. We further show that CpG ODN stimulation induces TNFR2 expression, which correlates with IL-10 secretion and terminal differentiation. Indeed, flow cytometric sorting of TNFR2+ B cells revealed that TNFR2+ and TNFR2- fractions correspond to IL-10+ and IL-10- fractions, respectively. Furthermore, CpG-induced TNFR2+ B cells were predominantly found in the IgM+ CD27+ B cell subset and spontaneously released immunoglobulin. Finally, our data corroborate the functional impact of TNFR2 by demonstrating that stimulation with a TNFR2 agonist significantly augments IL-10 and IL-6 production in B cells. Altogether, our data highlight a new role for TNFR2 in IL-10-secreting human B lymphocytes along with the potential to exploit this finding for sorting and isolation of this currently ill-defined B cell subset.}, language = {en} } @article{SiebertCiatoMurakamietal.2019, author = {Siebert, Claudia and Ciato, Denis and Murakami, Masanori and Frei-Stuber, Ludwig and Perez-Rivas, Luis Gustavo and Monteserin-Garcia, Jos{\´e} Luis and N{\"o}lting, Svenja and Maurer, Julian and Feuchtinger, Annette and Walch, Axel K. and Haak, Harm R. and Bertherat, J{\´e}r{\^o}me and Mannelli, Massimo and Fassnacht, Martin and Korpershoek, Esther and Reincke, Martin and Stalla, G{\"u}nter K. and Hantel, Constanze and Beuschlein, Felix}, title = {Heat Shock Protein 90 as a Prognostic Marker and Therapeutic Target for Adrenocortical Carcinoma}, series = {Frontiers in Endocrinology}, volume = {10}, journal = {Frontiers in Endocrinology}, doi = {10.3389/fendo.2019.00487}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-238029}, year = {2019}, abstract = {Background: Adrenocortical carcinoma (ACC) is a rare tumor entity with restricted therapeutic opportunities. HSP90 (Heat Shock Protein 90) chaperone activity is fundamental for cell survival and contributes to different oncogenic signaling pathways. Indeed, agents targeting HSP90 function have shown therapeutic efficacy in several cancer types. We have examined the expression of HSP90 in different adrenal tumors and evaluated the use of HSP90 inhibitors in vitro as possible therapy for ACC. Methods: Immunohistochemical expression of HSP90 isoforms was investigated in different adrenocortical tumors and associated with clinical features. Additionally, a panel of N-terminal (17-allylamino-17-demethoxygeldanamycin (17-AAG), luminespib, and ganetespib) and C-terminal (novobiocin and silibinin) HSP90 inhibitors were tested on various ACC cell lines. Results: Within adrenocortical tumors, ACC samples exhibited the highest expression of HSP90β. Within a cohort of ACC patients, HSP90β expression levels were inversely correlated with recurrence-free and overall survival. In functional assays, among five different compounds tested luminespib and ganetespib induced a significant decrease in cell viability in single as well as in combined treatments with compounds of the clinically used EDP-M scheme (etoposide, doxorubicin, cisplatin, mitotane). Inhibition of cell viability correlated furthermore with a decrease in proliferation, in cell migration and an increase in apoptosis. Moreover, analysis of cancer pathways indicated a modulation of the ERK1/2—and AKT—pathways by luminespib and ganetespib treatment. Conclusions: Our findings emphasize HSP90 as a marker with prognostic impact and promising target with N-terminal HSP90 inhibitors as drugs with potential therapeutic efficacy toward ACC.}, language = {en} } @article{SchurigHaeuslerGrittneretal.2019, author = {Schurig, Johannes and Haeusler, Karl Georg and Grittner, Ulrike and Nolte, Christian H. and Fiebach, Jochen B. and Audebert, Heinrich J. and Endres, Matthias and Rocco, Andrea}, title = {Frequency of Hemorrhage on Follow Up Imaging in Stroke Patients Treated With rt-PA Depending on Clinical Course}, series = {Frontiers in Neurology}, volume = {10}, journal = {Frontiers in Neurology}, doi = {10.3389/fneur.2019.00368}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234947}, year = {2019}, abstract = {Background: According to current guidelines, stroke patients treated with rt-PA should undergo brain imaging to exclude intracerebral bleeding 24 h after thrombolysis, before the start of medical secondary prevention. However, the usefulness of routine follow-up imaging with regard to changes in therapeutic management in patients without neurological deterioration is unclear. We hypothesized that follow up brain imaging solely to exclude bleeding in patients who clinically improved after rt-PA application may not be necessary. Methods: Retrospective single-center analysis including stroke patients treated with rt-PA. Records were reviewed for hemorrhagic transformation one day after systemic thrombolysis and brain imaging-based changes in therapeutic management. Twenty-four hour after thrombolysis patients were divided into four groups: (1) increased NIHSS score; (2) unchanged NIHSS score; (3) improved NIHSS score and; (4) NIHSS score = 0. Results: Out of 188 patients (mean age 73 years, 100 female) receiving rt-PA, 32 (17\%) had imaging-proven hemorrhagic transformation including 11 (6\%) patients with parenchymal hemorrhage. Patients in group (1, 2) more often had hypertension (p = 0.015) and more often had parenchymal hemorrhage (9 vs. 4\%; p < 0.206) compared to group (3, 4) and imaging-based changes in therapeutic management were more frequent (19\% vs. 6\%; p = 0.007). Patients of group (3, 4) had no changes in therapeutic management in 94\% of the cases. Patients in group (4) had no hemorrhagic transformation in routine follow-up brain imaging. Conclusions: Frequency of hemorrhagic transformation in Routine follow-up brain imaging and consecutive changes in therapeutic management were different depending on clinical course measured by NHISS score.}, language = {en} } @article{SchroeterPawelkeBiseniusetal.2018, author = {Schroeter, Matthias L. and Pawelke, Sarah and Bisenius, Sandrine and Kynast, Jana and Schuemberg, Katharina and Polyakova, Maryna and Anderl-Straub, Sarah and Danek, Adrian and Fassbender, Klaus and Jahn, Holger and Jessen, Frank and Kornhuber, Johannes and Lauer, Martin and Prudlo, Johannes and Schneider, Anja and Uttner, Ingo and Th{\"o}ne-Otto, Angelika and Otto, Markus and Diehl-Schmid, Janine}, title = {A Modified Reading the Mind in the Eyes Test Predicts Behavioral Variant Frontotemporal Dementia Better Than Executive Function Tests}, series = {Frontiers in Aging Neuroscience}, volume = {10}, journal = {Frontiers in Aging Neuroscience}, organization = {FTLD Study Group Germany}, doi = {10.3389/fnagi.2018.00011}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234254}, year = {2018}, abstract = {Behavioral variant frontotemporal dementia (bvFTD) is characterized by deep alterations in behavior and personality. Although revised diagnostic criteria agree for executive dysfunction as most characteristic, impairments in social cognition are also suggested. The study aimed at identifying those neuropsychological and behavioral parameters best discriminating between bvFTD and healthy controls. Eighty six patients were diagnosed with possible or probable bvFTD according to Rascovsky et al. (2011) and compared with 43 healthy age-matched controls. Neuropsychological performance was assessed with a modified Reading the Mind in the Eyes Test (RMET), Stroop task, Trail Making Test (TMT), Hamasch-Five-Point Test (H5PT), and semantic and phonemic verbal fluency tasks. Behavior was assessed with the Apathy Evaluation Scale, Frontal Systems Behavioral Scale, and Bayer Activities of Daily Living Scale. Each test's discriminatory power was investigated by Receiver Operating Characteristic curves calculating the area under the curve (AUC). bvFTD patients performed significantly worse than healthy controls in all neuropsychological tests. Discriminatory power (AUC) was highest in behavioral questionnaires, high in verbal fluency tasks and the RMET, and lower in executive function tests such as the Stroop task, TMT and H5PT. As fluency tasks depend on several cognitive functions, not only executive functions, results suggest that the RMET discriminated better between bvFTD and control subjects than other executive tests. Social cognition should be incorporated into diagnostic criteria for bvFTD in the future, such as in the International Classification of Diseases (ICD)-11, as already suggested in the Diagnostic and Statistical Manual for Mental Disorders (DSM)-5.}, language = {en} } @article{SchneiderWiewelhoveRaederetal.2019, author = {Schneider, Christoph and Wiewelhove, Thimo and Raeder, Christian and Flatt, Andrew A. and Hoos, Olaf and Hottenrott, Laura and Schumbera, Oliver and Kellmann, Michael and Meyer, Tim and Pfeiffer, Mark and Ferrauti, Alexander}, title = {Heart Rate Variability Monitoring During Strength and High-Intensity Interval Training Overload Microcycles}, series = {Frontiers in Physiology}, volume = {10}, journal = {Frontiers in Physiology}, doi = {10.3389/fphys.2019.00582}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231515}, year = {2019}, abstract = {Objective: In two independent study arms, we determine the effects of strength training (ST) and high-intensity interval training (HIIT) overload on cardiac autonomic modulation by measuring heart rate (HR) and vagal heart rate variability (HRV). Methods: In the study, 37 well-trained athletes (ST: 7 female, 12 male; HIIT: 9 female, 9 male) were subjected to orthostatic tests (HR and HRV recordings) each day during a 4-day baseline period, a 6-day overload microcycle, and a 4-day recovery period. Discipline-specific performance was assessed before and 1 and 4 days after training. Results: Following ST overload, supine HR, and vagal HRV (Ln RMSSD) were clearly increased and decreased (small effects), respectively, and the standing recordings remained unchanged. In contrast, HIIT overload resulted in decreased HR and increased Ln RMSSD in the standing position (small effects), whereas supine recordings remained unaltered. During the recovery period, these responses were reversed (ST: small effects, HIIT: trivial to small effects). The correlations between changes in HR, vagal HRV measures, and performance were weak or inconsistent. At the group and individual levels, moderate to strong negative correlations were found between HR and Ln RMSSD when analyzing changes between testing days (ST: supine and standing position, HIIT: standing position) and individual time series, respectively. Use of rolling 2-4-day averages enabled more precise estimation of mean changes with smaller confidence intervals compared to single-day values of HR or Ln RMSSD. However, the use of averaged values displayed unclear effects for evaluating associations between HR, vagal HRV measures, and performance changes, and have the potential to be detrimental for classification of individual short-term responses. Conclusion: Measures of HR and Ln RMSSD during an orthostatic test could reveal different autonomic responses following ST or HIIT which may not be discovered by supine or standing measures alone. However, these autonomic changes were not consistently related to short-term changes in performance and the use of rolling averages may alter these relationships differently on group and individual level.}, language = {en} } @article{PrustyGulveGovindetal.2018, author = {Prusty, Bhupesh K. and Gulve, Nitish and Govind, Sheila and Krueger, Gerhard R. F. and Feichtinger, Julia and Larcombe, Lee and Aspinall, Richard and Ablashi, Dharam V. and Toro, Carla T.}, title = {Active HHV-6 Infection of Cerebellar Purkinje Cells in Mood Disorders}, series = {Frontiers in Microbiology}, volume = {9}, journal = {Frontiers in Microbiology}, doi = {10.3389/fmicb.2018.01955}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-369222}, year = {2018}, abstract = {Early-life infections and associated neuroinflammation is incriminated in the pathogenesis of various mood disorders. Infection with human roseoloviruses, HHV-6A and HHV-6B, allows viral latency in the central nervous system and other tissues, which can later be activated causing cognitive and behavioral disturbances. Hence, this study was designed to evaluate possible association of HHV-6A and HHV-6B activation with three different groups of psychiatric patients. DNA qPCR, immunofluorescence and FISH studies were carried out in post-mortem posterior cerebellum from 50 cases each of bipolar disorder (BPD), schizophrenia, 15 major depressive disorder (MDD) and 50 appropriate control samples obtained from two well-known brain collections (Stanley Medical Research Institute). HHV-6A and HHV-6B late proteins (indicating active infection) and viral DNA were detected more frequently (p < 0.001 for each virus) in human cerebellum in MDD and BPD relative to controls. These roseolovirus proteins and DNA were found less frequently in schizophrenia cases. Active HHV-6A and HHV-6B infection in cerebellar Purkinje cells were detected frequently in BPD and MDD cases. Furthermore, we found a significant association of HHV-6A infection with reduced Purkinje cell size, suggesting virus-mediated abnormal Purkinje cell function in these disorders. Finally, gene expression analysis of cerebellar tissue revealed changes in pathways reflecting an inflammatory response possibly to HHV-6A infection. Our results provide molecular evidence to support a role for active HHV-6A and HHV-6B infection in BPD and MDD.}, language = {en} } @article{NagyvanGeffenStegneretal.2019, author = {Nagy, Magdolna and van Geffen, Johanna P. and Stegner, David and Adams, David J. and Braun, Attila and de Witt, Susanne M. and Elvers, Margitta and Geer, Mitchell J. and Kuijpers, Marijke J. E. and Kunzelmann, Karl and Mori, Jun and Oury, C{\´e}cile and Pircher, Joachim and Pleines, Irina and Poole, Alastair W. and Senis, Yotis A. and Verdoold, Remco and Weber, Christian and Nieswandt, Bernhard and Heemskerk, Johan W. M. and Baaten, Constance C. F. M. J.}, title = {Comparative Analysis of Microfluidics Thrombus Formation in Multiple Genetically Modified Mice: Link to Thrombosis and Hemostasis}, series = {Frontiers in Cardiovascular Medicine}, volume = {6}, journal = {Frontiers in Cardiovascular Medicine}, doi = {10.3389/fcvm.2019.00099}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-232194}, year = {2019}, abstract = {Genetically modified mice are indispensable for establishing the roles of platelets in arterial thrombosis and hemostasis. Microfluidics assays using anticoagulated whole blood are commonly used as integrative proxy tests for platelet function in mice. In the present study, we quantified the changes in collagen-dependent thrombus formation for 38 different strains of (genetically) modified mice, all measured with the same microfluidics chamber. The mice included were deficient in platelet receptors, protein kinases or phosphatases, small GTPases or other signaling or scaffold proteins. By standardized re-analysis of high-resolution microscopic images, detailed information was obtained on altered platelet adhesion, aggregation and/or activation. For a subset of 11 mouse strains, these platelet functions were further evaluated in rhodocytin- and laminin-dependent thrombus formation, thus allowing a comparison of glycoprotein VI (GPVI), C-type lectin-like receptor 2 (CLEC2) and integrin α6β1 pathways. High homogeneity was found between wild-type mice datasets concerning adhesion and aggregation parameters. Quantitative comparison for the 38 modified mouse strains resulted in a matrix visualizing the impact of the respective (genetic) deficiency on thrombus formation with detailed insight into the type and extent of altered thrombus signatures. Network analysis revealed strong clusters of genes involved in GPVI signaling and Ca2+ homeostasis. The majority of mice demonstrating an antithrombotic phenotype in vivo displayed with a larger or smaller reduction in multi-parameter analysis of collagen-dependent thrombus formation in vitro. Remarkably, in only approximately half of the mouse strains that displayed reduced arterial thrombosis in vivo, this was accompanied by impaired hemostasis. This was also reflected by comparing in vitro thrombus formation (by microfluidics) with alterations in in vivo bleeding time. In conclusion, the presently developed multi-parameter analysis of thrombus formation using microfluidics can be used to: (i) determine the severity of platelet abnormalities; (ii) distinguish between altered platelet adhesion, aggregation and activation; and (iii) elucidate both collagen and non-collagen dependent alterations of thrombus formation. This approach may thereby aid in the better understanding and better assessment of genetic variation that affect in vivo arterial thrombosis and hemostasis.}, language = {en} } @article{NguyenSaisingTribellietal.2019, author = {Nguyen, Minh-Thu and Saising, Jongkon and Tribelli, Paula Maria and Nega, Mulugeta and Diene, Seydina M. and Fran{\c{c}}ois, Patrice and Schrenzel, Jacques and Spr{\"o}er, Cathrin and Bunk, Boyke and Ebner, Patrick and Hertlein, Tobias and Kumari, Nimerta and H{\"a}rtner, Thomas and Wistuba, Dorothee and Voravuthikunchai, Supayang P. and M{\"a}der, Ulrike and Ohlsen, Knut and G{\"o}tz, Friedrich}, title = {Inactivation of farR Causes High Rhodomyrtone Resistance and Increased Pathogenicity in Staphylococcus aureus}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, doi = {10.3389/fmicb.2019.01157}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-224117}, year = {2019}, abstract = {Rhodomyrtone (Rom) is an acylphloroglucinol antibiotic originally isolated from leaves of Rhodomyrtus tomentosa. Rom targets the bacterial membrane and is active against a wide range of Gram-positive bacteria but the exact mode of action remains obscure. Here we isolated and characterized a spontaneous Rom-resistant mutant from the model strain Staphylococcus aureus HG001 (RomR) to learn more about the resistance mechanism. We showed that Rom-resistance is based on a single point mutation in the coding region of farR [regulator of fatty acid (FA) resistance] that causes an amino acid change from Cys to Arg at position 116 in FarR, that affects FarR activity. Comparative transcriptome analysis revealed that mutated farR affects transcription of many genes in distinct pathways. FarR represses for example the expression of its own gene (farR), its flanking gene farE (effector of FA resistance), and other global regulators such as agr and sarA. All these genes were consequently upregulated in the RomR clone. Particularly the upregulation of agr and sarA leads to increased expression of virulence genes rendering the RomR clone more cytotoxic and more pathogenic in a mouse infection model. The Rom-resistance is largely due to the de-repression of farE. FarE is described as an efflux pump for linoleic and arachidonic acids. We observed an increased release of lipids in the RomR clone compared to its parental strain HG001. If farE is deleted in the RomR clone, or, if native farR is expressed in the RomR strain, the corresponding strains become hypersensitive to Rom. Overall, we show here that the high Rom-resistance is mediated by overexpression of farE in the RomR clone, that FarR is an important regulator, and that the point mutation in farR (RomR clone) makes the clone hyper-virulent.}, language = {en} } @article{LangFuellsackWajant2018, author = {Lang, Isabell and F{\"u}llsack, Simone and Wajant, Harald}, title = {Lack of Evidence for a Direct Interaction of Progranulin and Tumor Necrosis Factor Receptor-1 and Tumor Necrosis Factor Receptor-2 From Cellular Binding Studies}, series = {Frontiers in Immunology}, volume = {9}, journal = {Frontiers in Immunology}, doi = {10.3389/fimmu.2018.00793}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236373}, year = {2018}, abstract = {Progranulin (PGRN) is a secreted anti-inflammatory protein which can be processed by neutrophil proteases to various granulins. It has been reported that at least a significant portion of the anti-inflammatory effects of PGRN is due to direct high affinity binding to tumor necrosis factor receptor-1 (TNFR1) and TNFR2 and inhibition of tumor necrosis factor (TNF)-induced TNFR1/2 signaling. Two studies failed to reproduce the interaction of TNFR1 and TNFR2 with PGRN, but follow up reports speculated that this was due to varying experimental circumstances and/or the use of PGRN from different sources. However, even under consideration of these speculations, there is still a striking discrepancy in the literature between the concentrations of PGRN needed to inhibit TNF signaling and the concentrations required to block TNF binding to TNFR1 and TNFR2. While signaling events induced by 0.2-2 nM of TNF have been efficiently inhibited by low, near to equimolar concentrations (0.5-2.5 nM) of PGRN in various studies, the reported inhibitory effects of PGRN on TNF-binding to TNFR1/2 required a huge excess of PGRN (100-1,000-fold). Therefore, we investigated the effect of PGRN on TNF binding to TNFR1 and TNFR2 in highly sensitive cellular binding studies. Unlabeled TNF inhibited >95\% of the specific binding of a Gaussia princeps luciferase (GpL) fusion protein of TNF to TNFR1 and TNFR2 and blocked binding of soluble GpL fusion proteins of TNFR1 and TNFR2 to membrane TNF expressing cells to >95\%, too. Purified PGRN, however, showed in both assays no effect on TNF-TNFR1/2 interaction even when applied in huge excess. To rule out that tags and purification- or storage-related effects compromise the potential ability of PGRN to bind TNF receptors, we directly co-expressed PGRN, and as control TNF, in TNFR1- and TNFR2-expressing cells and looked for binding of GpL-TNF. While expression of TNF strongly inhibited binding of GpL-TNF to TNFR1/2, co-expression of PGRN had not effect on the ability of the TNFR1/2-expressing cells to bind TNF.}, language = {en} } @article{KlotzHigginsSchaubmaretal.2019, author = {Klotz, Peter and Higgins, Paul G. and Schaubmar, Andreas R. and Failing, Klaus and Leidner, Ursula and Seifert, Harald and Scheufen, Sandra and Semmler, Torsten and Ewers, Christa}, title = {Seasonal Occurrence and Carbapenem Susceptibility of Bovine Acinetobacter baumannii in Germany}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, doi = {10.3389/fmicb.2019.00272}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-325927}, year = {2019}, abstract = {Acinetobacter baumannii is one of the leading causes of nosocomial infections in humans. To investigate its prevalence, distribution of sequence types (STs), and antimicrobial resistance in cattle, we sampled 422 cattle, including 280 dairy cows, 59 beef cattle, and 83 calves over a 14-month period. Metadata, such as the previous use of antimicrobial agents and feeding, were collected to identify putative determining factors. Bacterial isolates were identified via MALDI-TOF/MS and PCR, antimicrobial susceptibility was evaluated via VITEK2 and antibiotic gradient tests, resistance genes were identified by PCR. Overall, 15.6\% of the cattle harbored A. baumannii, predominantly in the nose (60.3\% of the A. baumannii isolates). It was more frequent in dairy cows (21.1\%) than in beef cattle (6.8\%) and calves (2.4\%). A seasonal occurrence was shown with a peak between May and August. The rate of occurrence of A. baumannii was correlated with a history of use of 3rd generation cephalosporins in the last 6 months prior to sampling Multilocus sequence typing (Pasteur scheme) revealed 83 STs among 126 unique isolates. Nine of the bovine STs have previously been implicated in human infections. Besides known intrinsic resistance of the species, the isolates did not show additional resistance to the antimicrobial substances tested, including carbapenems. Our data suggest that cattle are not a reservoir for nosocomial A. baumannii but carry a highly diverse population of this species. Nevertheless, some STs seem to be able to colonize both cattle and humans.}, language = {en} } @article{KervarrecSamimiGuyetantetal.2019, author = {Kervarrec, Thibault and Samimi, Mahtab and Guy{\´e}tant, Serge and Sarma, Bhavishya and Ch{\´e}ret, J{\´e}r{\´e}my and Blanchard, Emmanuelle and Berthon, Patricia and Schrama, David and Houben, Roland and Touz{\´e}, Antoine}, title = {Histogenesis of Merkel Cell Carcinoma: A Comprehensive Review}, series = {Frontiers in Oncology}, volume = {9}, journal = {Frontiers in Oncology}, doi = {10.3389/fonc.2019.00451}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-325733}, year = {2019}, abstract = {Merkel cell carcinoma (MCC) is a primary neuroendocrine carcinoma of the skin. This neoplasia features aggressive behavior, resulting in a 5-year overall survival rate of 40\%. In 2008, Feng et al. identified Merkel cell polyomavirus (MCPyV) integration into the host genome as the main event leading to MCC oncogenesis. However, despite identification of this crucial viral oncogenic trigger, the nature of the cell in which MCC oncogenesis occurs is actually unknown. In fact, several hypotheses have been proposed. Despite the large similarity in phenotype features between MCC tumor cells and physiological Merkel cells (MCs), a specialized subpopulation of the epidermis acting as mechanoreceptor of the skin, several points argue against the hypothesis that MCC derives directly from MCs. Alternatively, MCPyV integration could occur in another cell type and induce acquisition of an MC-like phenotype. Accordingly, an epithelial as well as a fibroblastic or B-cell origin of MCC has been proposed mainly based on phenotype similarities shared by MCC and these potential ancestries. The aim of this present review is to provide a comprehensive review of the current knowledge of the histogenesis of MCC.}, language = {en} } @article{KasaragodSchindelin2018, author = {Kasaragod, Vikram B. and Schindelin, Hermann}, title = {Structure-Function Relationships of Glycine and GABAA Receptors and Their Interplay With the Scaffolding Protein Gephyrin}, series = {Frontiers in Molecular Neuroscience}, volume = {11}, journal = {Frontiers in Molecular Neuroscience}, doi = {10.3389/fnmol.2018.00317}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-325607}, year = {2018}, abstract = {Glycine and γ-aminobutyric acid (GABA) are the major determinants of inhibition in the central nervous system (CNS). These neurotransmitters target glycine and GABAA receptors, respectively, which both belong to the Cys-loop superfamily of pentameric ligand-gated ion channels (pLGICs). Interactions of the neurotransmitters with the cognate receptors result in receptor opening and a subsequent influx of chloride ions, which, in turn, leads to hyperpolarization of the membrane potential, thus counteracting excitatory stimuli. The majority of glycine receptors and a significant fraction of GABAA receptors (GABAARs) are recruited and anchored to the post-synaptic membrane by the central scaffolding protein gephyrin. This ∼93 kDa moonlighting protein is structurally organized into an N-terminal G-domain (GephG) connected to a C-terminal E-domain (GephE) via a long unstructured linker. Both inhibitory neurotransmitter receptors interact via a short peptide motif located in the large cytoplasmic loop located in between transmembrane helices 3 and 4 (TM3-TM4) of the receptors with a universal receptor-binding epitope residing in GephE. Gephyrin engages in nearly identical interactions with the receptors at the N-terminal end of the peptide motif, and receptor-specific interaction toward the C-terminal region of the peptide. In addition to its receptor-anchoring function, gephyrin also interacts with a rather large collection of macromolecules including different cytoskeletal elements, thus acting as central scaffold at inhibitory post-synaptic specializations. Dysfunctions in receptor-mediated or gephyrin-mediated neurotransmission have been identified in various severe neurodevelopmental disorders. Although biochemical, cellular and electrophysiological studies have helped to understand the physiological and pharmacological roles of the receptors, recent high resolution structures of the receptors have strengthened our understanding of the receptors and their gating mechanisms. Besides that, multiple crystal structures of GephE in complex with receptor-derived peptides have shed light into receptor clustering by gephyrin at inhibitory post-synapses. This review will highlight recent biochemical and structural insights into gephyrin and the GlyRs as well as GABAA receptors, which provide a deeper understanding of the molecular machinery mediating inhibitory neurotransmission.}, language = {en} } @article{JohnAbrantesPrustyetal.2019, author = {John, Cathy N. and Abrantes, Pedro M. D. S. and Prusty, Bhupesh K. and Ablashi, Dharam V. and Africa, Charlene W. J.}, title = {K21 Compound, a Potent Antifungal Agent: Implications for the Treatment of Fluconazole-Resistant HIV-Associated Candida Species}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, doi = {10.3389/fmicb.2019.01021}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-323505}, year = {2019}, abstract = {Background/Objectives: With mucocutaneous candidiasis being highly prevalent in HIV patients, the emergence of fluconazole-resistant Candida species forms a major challenge in treating and eradicating these infections. The objective of this study was to establish the antifungal activity of K21, a membrane-rupturing antimicrobial compound derived from a silica quaternary ammonium compound (SiQAC) with tetraethoxysilane (TEOS). Methods: The study sample included 81 Candida species of which 9 were type strains and 72 were clinical isolates. Minimum inhibitory concentrations, synergy, fractional inhibitory concentration index (FICI), and time kill assays were determined by broth microdilution. Electron microscopy (EM) was used to determine the qualitative changes brought about after treatment with K21. Results: K21 inhibited the growth of all fluconazole-resistant and susceptible Candida strains with only 2 h of exposure required to effectively kill 99.9\% of the inoculum, and a definite synergistic effect was observed with a combination of K21 and fluconazole. EM demonstrated the presence of two forms of extracellular vesicles indicative of biofilm formation and cell lysis. Conclusion: The study established the efficacy of K21 as an antifungal agent and with fluconazole-resistant candidiasis on the increase, the development of K21 can provide a promising alternative to combat acquired drug resistance.}, language = {en} } @article{GryszelSchlossarekWuerthneretal.2023, author = {Gryszel, Maciej and Schlossarek, Tim and W{\"u}rthner, Frank and Natali, Mirco and Głowacki, Eric Daniel}, title = {Water-soluble cationic perylene diimide dyes as stable photocatalysts for H\(_2\)O\(_2\) evolution}, series = {ChemPhotoChem}, volume = {7}, journal = {ChemPhotoChem}, number = {9}, issn = {2367-0932}, doi = {10.1002/cptc.202300070}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-370250}, year = {2023}, abstract = {Photocatalytic generation of hydrogen peroxide, H\(_2\)O\(_2\), has gained increasing attention in recent years, with applications ranging from solar energy conversion to biophysical research. While semiconducting solid-state materials are normally regarded as the workhorse for photogeneration of H\(_2\)O\(_2\), an intriguing alternative for on-demand H\(_2\)O\(_2\) is the use of photocatalytic organic dyes. Herein we report the use of water-soluble dyes based on perylene diimide molecules which behave as true molecular catalysts for the light-induced conversion of dissolved oxygen to hydrogen peroxide. In particular, we address how to obtain visible-light photocatalysts which are stable with respect to aggregation and photochemical degradation. We report on the factors affecting efficiency and stability, including variable electron donors, oxygen partial pressure, pH, and molecular catalyst structure. The result is a perylene diimide derivative with unprecedented peroxide evolution performance using a broad range of organic donor molecules and operating in a wide pH range.}, language = {en} }