@article{MuellerFiebigWeidaueretal.2013, author = {Mueller, Thomas D. and Fiebig, Juliane E. and Weidauer, Stella E. and Qiu, Li-Yan and Bauer, Markus and Schmieder, Peter and Beerbaum, Monika and Zhang, Jin-Li and Oschkinat, Hartmut and Sebald, Walter}, title = {The Clip-Segment of the von Willebrand Domain 1 of the BMP Modulator Protein Crossveinless 2 Is Preformed}, series = {Molecules}, journal = {Molecules}, doi = {10.3390/molecules181011658}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97196}, year = {2013}, abstract = {Bone Morphogenetic Proteins (BMPs) are secreted protein hormones that act as morphogens and exert essential roles during embryonic development of tissues and organs. Signaling by BMPs occurs via hetero-oligomerization of two types of serine/threonine kinase transmembrane receptors. Due to the small number of available receptors for a large number of BMP ligands ligand-receptor promiscuity presents an evident problem requiring additional regulatory mechanisms for ligand-specific signaling. Such additional regulation is achieved through a plethora of extracellular antagonists, among them members of the Chordin superfamily, that modulate BMP signaling activity by binding. The key-element in Chordin-related antagonists for interacting with BMPs is the von Willebrand type C (VWC) module, which is a small domain of about 50 to 60 residues occurring in many different proteins. Although a structure of the VWC domain of the Chordin-member Crossveinless 2 (CV2) bound to BMP-2 has been determined by X-ray crystallography, the molecular mechanism by which the VWC domain binds BMPs has remained unclear. Here we present the NMR structure of the Danio rerio CV2 VWC1 domain in its unbound state showing that the key features for high affinity binding to BMP-2 is a pre-oriented peptide loop.}, language = {en} } @article{WinterKampfHelluyetal.2013, author = {Winter, Patrick and Kampf, Thomas and Helluy, Xavier and Gutjahr, Fabian T. and Meyer, Cord B. and Rommel, Eberhard and Bauer, Wolfgang R. and Jakob, Peter M. and Herold, Volker}, title = {Fast retrospectively triggered local pulse-wave velocity measurements in mice with CMR-microscopy using a radial trajectory}, series = {Journal of Cardiovascular Magnetic Resonance}, journal = {Journal of Cardiovascular Magnetic Resonance}, doi = {10.1186/1532-429X-15-88}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96602}, year = {2013}, abstract = {Background The aortic pulse-wave velocity (PWV) is an important indicator of cardiovascular risk. In recent studies MRI methods have been developed to measure this parameter noninvasively in mice. Present techniques require additional hardware for cardiac and respiratory gating. In this work a robust self-gated measurement of the local PWV in mice without the need of triggering probes is proposed. Methods The local PWV of 6-months-old wild-type C57BL/6J mice (n=6) was measured in the abdominal aorta with a retrospectively triggered radial Phase Contrast (PC) MR sequence using the flow-area (QA) method. A navigator signal was extracted from the CMR data of highly asymmetric radial projections with short repetition time (TR=3 ms) and post-processed with high-pass and low-pass filters for retrospective cardiac and respiratory gating. The self-gating signal was used for a reconstruction of high-resolution Cine frames of the aortic motion. To assess the local PWV the volume flow Q and the cross-sectional area A of the aorta were determined. The results were compared with the values measured with a triggered Cartesian and an undersampled triggered radial PC-Cine sequence. Results In all examined animals a self-gating signal could be extracted and used for retrospective breath-gating and PC-Cine reconstruction. With the non-triggered measurement PWV values of 2.3±0.2 m/s were determined. These values are in agreement with those measured with the triggered Cartesian (2.4±0.2 m/s) and the triggered radial (2.3±0.2 m/s) measurement. Due to the strong robustness of the radial trajectory against undersampling an acceleration of more than two relative to the prospectively triggered Cartesian sampling could be achieved with the retrospective method. Conclusion With the radial flow-encoding sequence the extraction of a self-gating signal is feasible. The retrospective method enables a robust and fast measurement of the local PWV without the need of additional trigger hardware.}, language = {en} } @article{SepahiFaustSturmetal.2019, author = {Sepahi, Ilnaz and Faust, Ulrike and Sturm, Marc and Bosse, Kristin and Kehrer, Martin and Heinrich, Tilman and Grundman-Hauser, Kathrin and Bauer, Peter and Ossowski, Stephan and Susak, Hana and Varon, Raymonda and Schr{\"o}ck, Evelin and Niederacher, Dieter and Auber, Bernd and Sutter, Christian and Arnold, Norbert and Hahnen, Eric and Dworniczak, Bernd and Wang-Gorke, Shan and Gehrig, Andrea and Weber, Bernhard H. F. and Engel, Christoph and Lemke, Johannes R. and Hartkopf, Andreas and Huu Phuc, Nguyen and Riess, Olaf and Schroeder, Christopher}, title = {Investigating the effects of additional truncating variants in DNA-repair genes on breast cancer risk in BRCA1-positive women}, series = {BMC Cancer}, volume = {19}, journal = {BMC Cancer}, doi = {10.1186/s12885-019-5946-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-237676}, year = {2019}, abstract = {Background Inherited pathogenic variants in BRCA1 and BRCA2 are the most common causes of hereditary breast and ovarian cancer (HBOC). The risk of developing breast cancer by age 80 in women carrying a BRCA1 pathogenic variant is 72\%. The lifetime risk varies between families and even within affected individuals of the same family. The cause of this variability is largely unknown, but it is hypothesized that additional genetic factors contribute to differences in age at onset (AAO). Here we investigated whether truncating and rare missense variants in genes of different DNA-repair pathways contribute to this phenomenon. Methods We used extreme phenotype sampling to recruit 133 BRCA1-positive patients with either early breast cancer onset, below 35 (early AAO cohort) or cancer-free by age 60 (controls). Next Generation Sequencing (NGS) was used to screen for variants in 311 genes involved in different DNA-repair pathways. Results Patients with an early AAO (73 women) had developed breast cancer at a median age of 27 years (interquartile range (IQR); 25.00-27.00 years). A total of 3703 variants were detected in all patients and 43 of those (1.2\%) were truncating variants. The truncating variants were found in 26 women of the early AAO group (35.6\%; 95\%-CI 24.7 - 47.7\%) compared to 16 women of controls (26.7\%; 95\%-CI 16.1 to 39.7\%). When adjusted for environmental factors and family history, the odds ratio indicated an increased breast cancer risk for those carrying an additional truncating DNA-repair variant to BRCA1 mutation (OR: 3.1; 95\%-CI 0.92 to 11.5; p-value = 0.07), although it did not reach the conventionally acceptable significance level of 0.05. Conclusions To our knowledge this is the first time that the combined effect of truncating variants in DNA-repair genes on AAO in patients with hereditary breast cancer is investigated. Our results indicate that co-occurring truncating variants might be associated with an earlier onset of breast cancer in BRCA1-positive patients. Larger cohorts are needed to confirm these results.}, language = {en} } @article{WinterAndelovicKampfetal.2021, author = {Winter, Patrick M. and Andelovic, Kristina and Kampf, Thomas and Hansmann, Jan and Jakob, Peter Michael and Bauer, Wolfgang Rudolf and Zernecke, Alma and Herold, Volker}, title = {Simultaneous measurements of 3D wall shear stress and pulse wave velocity in the murine aortic arch}, series = {Journal of Cardiovascular Magnetic Resonance}, volume = {23}, journal = {Journal of Cardiovascular Magnetic Resonance}, number = {1}, doi = {10.1186/s12968-021-00725-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259152}, pages = {34}, year = {2021}, abstract = {Purpose Wall shear stress (WSS) and pulse wave velocity (PWV) are important parameters to characterize blood flow in the vessel wall. Their quantification with flow-sensitive phase-contrast (PC) cardiovascular magnetic resonance (CMR), however, is time-consuming. Furthermore, the measurement of WSS requires high spatial resolution, whereas high temporal resolution is necessary for PWV measurements. For these reasons, PWV and WSS are challenging to measure in one CMR session, making it difficult to directly compare these parameters. By using a retrospective approach with a flexible reconstruction framework, we here aimed to simultaneously assess both PWV and WSS in the murine aortic arch from the same 4D flow measurement. Methods Flow was measured in the aortic arch of 18-week-old wildtype (n = 5) and ApoE\(^{-/-}\) mice (n = 5) with a self-navigated radial 4D-PC-CMR sequence. Retrospective data analysis was used to reconstruct the same dataset either at low spatial and high temporal resolution (PWV analysis) or high spatial and low temporal resolution (WSS analysis). To assess WSS, the aortic lumen was labeled by semi-automatically segmenting the reconstruction with high spatial resolution. WSS was determined from the spatial velocity gradients at the lumen surface. For calculation of the PWV, segmentation data was interpolated along the temporal dimension. Subsequently, PWV was quantified from the through-plane flow data using the multiple-points transit-time method. Reconstructions with varying frame rates and spatial resolutions were performed to investigate the influence of spatiotemporal resolution on the PWV and WSS quantification. Results 4D flow measurements were conducted in an acquisition time of only 35 min. Increased peak flow and peak WSS values and lower errors in PWV estimation were observed in the reconstructions with high temporal resolution. Aortic PWV was significantly increased in ApoE\(^{-/-}\) mice compared to the control group (1.7 ± 0.2 versus 2.6 ± 0.2 m/s, p < 0.001). Mean WSS magnitude values averaged over the aortic arch were (1.17 ± 0.07) N/m\(^2\) in wildtype mice and (1.27 ± 0.10) N/m\(^2\) in ApoE\(^{-/-}\) mice. Conclusion The post processing algorithm using the flexible reconstruction framework developed in this study permitted quantification of global PWV and 3D-WSS in a single acquisition. The possibility to assess both parameters in only 35 min will markedly improve the analyses and information content of in vivo measurements.}, language = {en} } @article{ForchertPotapovaPanettaetal.2022, author = {Forchert, Leandra and Potapova, Ekaterina and Panetta, Valentina and Dramburg, Stephanie and Perna, Serena and Posa, Daniela and Resch-Marat, Yvonne and Lupinek, Christian and Rohrbach, Alexander and Grabenhenrich, Linus and Icke, Katja and Bauer, Carl-Peter and Hoffman, Ute and Forster, Johannes and Zepp, Fred and Schuster, Antje and Wahn, Ulrich and Keil, Thomas and Lau, Susanne and Vrtala, Susanne and Valenta, Rudolf and Matricardi, Paolo Maria}, title = {Der p 23-specific IgE response throughout childhood and its association with allergic disease: A birth cohort study}, series = {Pediatric Allergy and Immunology}, volume = {33}, journal = {Pediatric Allergy and Immunology}, number = {7}, doi = {10.1111/pai.13829}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-287181}, year = {2022}, abstract = {Background The Dermatophagoides pteronyssinus molecule Der p 23 is a major allergen whose clinical relevance has been shown in cross-sectional studies. We longitudinally analysed the trajectory of Der p 23-specific IgE antibody (sIgE) levels throughout childhood and youth, their early-life determinants and their clinical relevance for allergic rhinitis and asthma. Methods We obtained sera and clinical data of 191 participants of the German Multicentre Allergy Study, a prospective birth cohort. Serum samples from birth to 20 years of age with sIgE reactivity to Der p 23 in a customised semiquantitative microarray were newly analysed with a singleplex quantitative assay. Early mite exposure was assessed by measuring the average content of Der p 1 in house dust at 6 and 18 months. Results Der p 23-sIgE levels were detected at least once in 97/191 participants (51\%). Prevalence of Der p 23 sensitisation and mean sIgE levels increased until age 10 years, plateaued until age 13 years and were lowest at age 20 years. Asthma, allergic rhinitis (AR) and atopic dermatitis (AD) were more prevalent in Der p 23-sensitised children, including those with monomolecular but persistent sensitisation (11/97, 11\%). A higher exposure to mites in infancy and occurrence of AD before 5 years of age preceded the onset of Der p 23 sensitisation, which in turn preceded a higher incidence of asthma. Conclusions Der p 23 sensitisation peaks in late childhood and then decreases. It is preceded by early mite exposure and AD. Asthma and AR can occur in patients persistently sensitised to Der p 23 as the only mite allergen, suggesting the inclusion of molecular testing of Der p 23-sIgE for subjects with clinical suspicion of HDM allergy but without sIgE to other major D.pt. allergens.}, language = {en} } @article{LueffeD'OrazioBaueretal.2021, author = {L{\"u}ffe, Teresa M. and D'Orazio, Andrea and Bauer, Moritz and Gioga, Zoi and Schoeffler, Victoria and Lesch, Klaus-Peter and Romanos, Marcel and Drepper, Carsten and Lillesaar, Christina}, title = {Increased locomotor activity via regulation of GABAergic signalling in foxp2 mutant zebrafish - implications for neurodevelopmental disorders}, series = {Translational Psychiatry}, volume = {11}, journal = {Translational Psychiatry}, doi = {10.1038/s41398-021-01651-w}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-264713}, year = {2021}, abstract = {Recent advances in the genetics of neurodevelopmental disorders (NDDs) have identified the transcription factor FOXP2 as one of numerous risk genes, e.g. in autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD). FOXP2 function is suggested to be involved in GABAergic signalling and numerous studies demonstrate that GABAergic function is altered in NDDs, thus disrupting the excitation/inhibition balance. Interestingly, GABAergic signalling components, including glutamate-decarboxylase 1 (Gad1) and GABA receptors, are putative transcriptional targets of FOXP2. However, the specific role of FOXP2 in the pathomechanism of NDDs remains elusive. Here we test the hypothesis that Foxp2 affects behavioural dimensions via GABAergic signalling using zebrafish as model organism. We demonstrate that foxp2 is expressed by a subset of GABAergic neurons located in brain regions involved in motor functions, including the subpallium, posterior tuberculum, thalamus and medulla oblongata. Using CRISPR/Cas9 gene-editing we generated a novel foxp2 zebrafish loss-of-function mutant that exhibits increased locomotor activity. Further, genetic and/or pharmacological disruption of Gad1 or GABA-A receptors causes increased locomotor activity, resembling the phenotype of foxp2 mutants. Application of muscimol, a GABA-A receptor agonist, rescues the hyperactive phenotype induced by the foxp2 loss-of-function. By reverse translation of the therapeutic effect on hyperactive behaviour exerted by methylphenidate, we note that application of methylphenidate evokes different responses in wildtype compared to foxp2 or gad1b loss-of-function animals. Together, our findings support the hypothesis that foxp2 regulates locomotor activity via GABAergic signalling. This provides one targetable mechanism, which may contribute to behavioural phenotypes commonly observed in NDDs.}, language = {en} } @article{PrantlZeckBaueretal.2022, author = {Prantl, Thomas and Zeck, Timo and Bauer, Andre and Ten, Peter and Prantl, Dominik and Yahya, Ala Eddine Ben and Ifflaender, Lukas and Dmitrienko, Alexandra and Krupitzer, Christian and Kounev, Samuel}, title = {A Survey on Secure Group Communication Schemes With Focus on IoT Communication}, series = {IEEE Access}, volume = {10}, journal = {IEEE Access}, doi = {10.1109/ACCESS.2022.3206451}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300257}, pages = {99944 -- 99962}, year = {2022}, abstract = {A key feature for Internet of Things (IoT) is to control what content is available to each user. To handle this access management, encryption schemes can be used. Due to the diverse usage of encryption schemes, there are various realizations of 1-to-1, 1-to-n, and n-to-n schemes in the literature. This multitude of encryption methods with a wide variety of properties presents developers with the challenge of selecting the optimal method for a particular use case, which is further complicated by the fact that there is no overview of existing encryption schemes. To fill this gap, we envision a cryptography encyclopedia providing such an overview of existing encryption schemes. In this survey paper, we take a first step towards such an encyclopedia by creating a sub-encyclopedia for secure group communication (SGC) schemes, which belong to the n-to-n category. We extensively surveyed the state-of-the-art and classified 47 different schemes. More precisely, we provide (i) a comprehensive overview of the relevant security features, (ii) a set of relevant performance metrics, (iii) a classification for secure group communication schemes, and (iv) workflow descriptions of the 47 schemes. Moreover, we perform a detailed performance and security evaluation of the 47 secure group communication schemes. Based on this evaluation, we create a guideline for the selection of secure group communication schemes.}, language = {en} } @article{AndelovicWinterKampfetal.2021, author = {Andelovic, Kristina and Winter, Patrick and Kampf, Thomas and Xu, Anton and Jakob, Peter Michael and Herold, Volker and Bauer, Wolfgang Rudolf and Zernecke, Alma}, title = {2D Projection Maps of WSS and OSI Reveal Distinct Spatiotemporal Changes in Hemodynamics in the Murine Aorta during Ageing and Atherosclerosis}, series = {Biomedicines}, volume = {9}, journal = {Biomedicines}, number = {12}, issn = {2227-9059}, doi = {10.3390/biomedicines9121856}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-252164}, year = {2021}, abstract = {Growth, ageing and atherosclerotic plaque development alter the biomechanical forces acting on the vessel wall. However, monitoring the detailed local changes in wall shear stress (WSS) at distinct sites of the murine aortic arch over time has been challenging. Here, we studied the temporal and spatial changes in flow, WSS, oscillatory shear index (OSI) and elastic properties of healthy wildtype (WT, n = 5) and atherosclerotic apolipoprotein E-deficient (Apoe\(^{-/-}\), n = 6) mice during ageing and atherosclerosis using high-resolution 4D flow magnetic resonance imaging (MRI). Spatially resolved 2D projection maps of WSS and OSI of the complete aortic arch were generated, allowing the pixel-wise statistical analysis of inter- and intragroup hemodynamic changes over time and local correlations between WSS, pulse wave velocity (PWV), plaque and vessel wall characteristics. The study revealed converse differences of local hemodynamic profiles in healthy WT and atherosclerotic Apoe\(^{-/-}\) mice, and we identified the circumferential WSS as potential marker of plaque size and composition in advanced atherosclerosis and the radial strain as a potential marker for vascular elasticity. Two-dimensional (2D) projection maps of WSS and OSI, including statistical analysis provide a powerful tool to monitor local aortic hemodynamics during ageing and atherosclerosis. The correlation of spatially resolved hemodynamics and plaque characteristics could significantly improve our understanding of the impact of hemodynamics on atherosclerosis, which may be key to understand plaque progression towards vulnerability.}, language = {en} } @article{MarxSchindlerMoschetal.2016, author = {Marx, Gernot and Schindler, Achim W. and Mosch, Christoph and Albers, Joerg and Bauer, Michael and Gnass, Irmela and Hobohm, Carsten and Janssens, Uwe and Kluge, Stefan and Kranke, Peter and Maurer, Tobias and Merz, Waltraut and Neugebauer, Edmund and Quintel, Michael and Senninger, Norbert and Trampisch, Hans-Joachim and Waydhas, Christian and Wildenauer, Rene and Zacharowski, Kai and Eikermann, Michaela}, title = {Intravascular volume therapy in adults guidelines from the association of the scientific medical societies in Germany}, series = {European Journal of Anaesthesiology}, volume = {33}, journal = {European Journal of Anaesthesiology}, number = {7}, doi = {10.1097/EJA.0000000000000447}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188223}, pages = {488-521}, year = {2016}, abstract = {No abstract available.}, language = {en} } @article{AndelovicWinterJakobetal.2021, author = {Andelovic, Kristina and Winter, Patrick and Jakob, Peter Michael and Bauer, Wolfgang Rudolf and Herold, Volker and Zernecke, Alma}, title = {Evaluation of plaque characteristics and inflammation using magnetic resonance imaging}, series = {Biomedicines}, volume = {9}, journal = {Biomedicines}, number = {2}, issn = {2227-9059}, doi = {10.3390/biomedicines9020185}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-228839}, year = {2021}, abstract = {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.}, language = {en} }