@article{MietchenHagedornFoerstneretal.2011, author = {Mietchen, Daniel and Hagedorn, Gregor and F{\"o}rstner, Konrad U. and Kubke, M Fabiana and Koltzenburg, Claudia and Hahnel, Mark J. and Penev, Lyubomir}, title = {Wikis in scholarly publishing}, doi = {10.3233/ISU-2011-0621}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-87770}, year = {2011}, abstract = {Scientific research is a process concerned with the creation, collective accumulation, contextualization, updating and maintenance of knowledge. Wikis provide an environment that allows to collectively accumulate, contextualize, update and maintain knowledge in a coherent and transparent fashion. Here, we examine the potential of wikis as platforms for scholarly publishing. In the hope to stimulate further discussion, the article itself was drafted on Species-ID - a wiki that hosts a prototype for wiki-based scholarly publishing - where it can be updated, expanded or otherwise improved.}, subject = {Elektronisches Publizieren}, language = {en} } @phdthesis{Duenkeloh2011, author = {D{\"u}nkeloh, Armin}, title = {Water Balance Dynamics of Cyprus - Actual State and Impacts of Climate Change}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75165}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {A completely revised and enhanced version of the water balance model MODBIL of the regional water balance dynamics of Cyprus was developed for this study. The model is based on a physical, process-oriented, spatially distributed concept and is applied for the calculation of all important water balance components of the island for the time period of 1961-2004. The calibrated results are statistically analysed and visualised for the whole island area, and evaluated with respect to the renewability of natural water resources. Climate variability and changes of the past decades are analysed with regard to their influence on water balances. A further part of the study focusses on the simulation of impacts of potential climate change. The water balances are simulated under changing climatic conditions on the base of theoretical precipitation, temperature and relative humidity changes and the revealed impacts on the water balances and renewable resources are discussed. Furthermore, a first principal water balance scenario is developed for the assessment of the regional hydrological changes expected for Cyprus by the end of the 21st century. The scenarios are based on recently calculated climate change assessments for this part of the Mediterranean, under an assumed further increase of greenhouse gasses in the atmosphere.}, subject = {Wasserhaushalt}, language = {en} } @article{Pfister2011, author = {Pfister, Roland}, title = {Wardrobe Malfunctions and the Measurement of Internet Behaviour}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69067}, year = {2011}, abstract = {The wardrobe malfunction—an unanticipated exposure of bodily parts in the public—has become a prevailing issue in concerts, shows and other celebrity events that is reliably reported by the media. The internet as the fastest source for celebrity gossip allows measuring the impact of such wardrobe malfunctions on the public in-terest in a celebrity. This measurement in turn allows conclusions about intention, motivation, and internet be-haviour of a wide variety of internet users. The present study exemplifies the use of an innovative non-reactive measure of active interest—the Search Volume Index—to assess the impact of a variety of internet-related phe-nomena, including wardrobe malfunctions. Results indicate that interest in a celebrity increases immediately af-ter such an event and stays at a high level for about three weeks (the wardrobe plateau). This special form of ce-lebrity gossip thus meets a constant interest of a substantial proportion of internet users.}, subject = {Psychologie}, language = {en} } @article{JakobHertleinSturmetal.2011, author = {Jakob, Peter and Hertlein, Tobias and Sturm, Volker and Kircher, Stefan and Basse-L{\"u}sebrink, Thomas and Haddad, Daniel and Ohlsen, Knut}, title = {Visualization of Abscess Formation in a Murine Thigh Infection Model of Staphylococcus aureus by 19F-Magnetic Resonance Imaging (MRI)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-74994}, year = {2011}, abstract = {Background: During the last years, 19F-MRI and perfluorocarbon nanoemulsion (PFC) emerged as a powerful contrast agent based MRI methodology to track cells and to visualize inflammation. We applied this new modality to visualize deep tissue abscesses during acute and chronic phase of inflammation caused by Staphylococcus aureus infection. Methodology and Principal Findings: In this study, a murine thigh infection model was used to induce abscess formation and PFC or CLIO (cross linked ironoxides) was administered during acute or chronic phase of inflammation. 24 h after inoculation, the contrast agent accumulation was imaged at the site of infection by MRI. Measurements revealed a strong accumulation of PFC at the abscess rim at acute and chronic phase of infection. The pattern was similar to CLIO accumulation at chronic phase and formed a hollow sphere around the edema area. Histology revealed strong influx of neutrophils at the site of infection and to a smaller extend macrophages during acute phase and strong influx of macrophages at chronic phase of inflammation. Conclusion and Significance: We introduce 19F-MRI in combination with PFC nanoemulsions as a new platform to visualize abscess formation in a murine thigh infection model of S. aureus. The possibility to track immune cells in vivo by this modality offers new opportunities to investigate host immune response, the efficacy of antibacterial therapies and the influence of virulence factors for pathogenesis.}, subject = {Staphylococcus aureus}, language = {en} } @article{HertleinSturmKircheretal.2011, author = {Hertlein, Tobias and Sturm, Volker and Kircher, Stefan and Basse-L{\"u}sebrink, Thomas and Haddad, Daniel and Ohlsen, Knut and Jakob, Peter}, title = {Visualization of Abscess Formation in a Murine Thigh Infection Model of \(Staphylococcus\) \(aureus\) by (19)F-Magnetic Resonance Imaging (MRI)}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {3}, doi = {10.1371/journal.pone.0018246}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142846}, pages = {e18246}, year = {2011}, abstract = {Background: During the last years, (19)F-MRI and perfluorocarbon nanoemulsion (PFC) emerged as a powerful contrast agent methodology to track cells and to visualize inflammation. We applied this new modality to visualize deep tissue abscesses during acute and chronic phase of inflammation caused by Staphylococcus aureus infection. Methodology and Principal Findings: In this study, a murine thigh infection model was used to induce abscess formation and PFC or CLIO (cross linked ironoxides) was administered during acute or chronic phase of inflammation. 24 h after inoculation, the contrast agent accumulation was imaged at the site of infection by MRI. Measurements revealed a strong accumulation of PFC at the abscess rim at acute and chronic phase of infection. The pattern was similar to CLIO accumulation at chronic phase and formed a hollow sphere around the edema area. Histology revealed strong influx of neutrophils at the site of infection and to a smaller extend macrophages during acute phase and strong influx of macrophages at chronic phase of inflammation. Conclusion and Significance: We introduce (19)F-MRI in combination with PFC nanoemulsions as a new platform to visualize abscess formation in a murine thigh infection model of S. aureus. The possibility to track immune cells in vivo by this modality offers new opportunities to investigate host immune response, the efficacy of antibacterial therapies and the influence of virulence factors for pathogenesis.}, language = {en} } @phdthesis{Sareen2011, author = {Sareen, Preeti}, title = {Visual attention in Drosophila melanogaster}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69616}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {There is such vast amount of visual information in our surroundings at any time that filtering out the important information for further processing is a basic requirement for any visual system. This is accomplished by deploying attention to focus on one source of sensory inputs to the exclusion of others (Luck and Mangun 2009). Attention has been studied extensively in humans and non human primates (NHPs). In Drosophila, visual attention was first demonstrated in 1980 (Wolf and Heisenberg 1980) but this field remained largely unexplored until recently. Lately, however, studies have emerged that hypothesize the role of attention in several behaviors but do not specify the characteristic properties of attention. So, the aim of this research was to characterize the phenomenon of visual attention in wild-type Drosophila, including both externally cued and covert attention using tethered flight at a torque meter. Development of systematic quantifiable behavioral tests was a key aspect for this which was not only important for analyzing the behavior of a population of wild-type flies but also for comparing the wild-type flies with mutant flies. The latter would help understand the molecular, genetic, and neuronal bases of attention. Since Drosophila provides handy genetic tools, a model of attention in Drosophila will serve to the greater questions about the neuronal circuitry and mechanisms involved which might be analogous to those in primates. Such a model might later be used in research involving disorders of attention. Attention can be guided to a certain location in the visual field by the use of external cues. Here, using visual cues the attention of the fly was directed to one or the other of the two visual half-fields. A simple yet robust paradigm was designed with which the results were easily quantifiable. This paradigm helped discover several interesting properties of the cued attention, the most substantial one being that this kind of external guidance of attention is restricted to the lower part of the fly's visual field. The guiding cue had an after-effect, i.e. it could occur at least up to 2 seconds before the test and still bias it. The cue could also be spatially separated from the test by at least 20° and yet attract the attention although the extent of the focus of attention (FoA) was smaller than one lower visual half-field. These observations excluded the possibility of any kind of interference between the test and the cue stimuli. Another interesting observation was the essentiality of continuous visibility of the test stimulus but not the cue for effective cuing. When the contrast of the visual scene was inverted, differences in response frequencies and cuing effects were observed. Syndirectional yaw torque responses became more frequent than the antidirectional responses and cuing was no longer effective in the lower visual field with inverted contrast. Interestingly, the test stimulus with simultaneous displacement of two stripes not only effectuated a phasic yaw torque response but also a landing response. A 50 landing response was produced in more than half of the cases whenever a yaw torque response was produced. Elucidation of the neuronal correlates of the cued attention was commenced. Pilot experiments with hydroxyurea (HU) treated flies showed that mushroom bodies were not required for the kind of guidance of attention tested in this study. Dopamine mutants were also tested for the guidance of attention in the lower visual field. Surprisingly, TH-Gal4/UAS-shits1 flies flew like wild-type flies and also showed normal optomotor response during the initial calibration phase of the experiment but did not show any phasic yaw torque or landing response at 18 °C, 25 °C or 30 °C. dumb2 flies that have almost no D1 dopamine receptor dDA1 expression in the mushroom bodies and the central complex (Kim et al. 2007) were also tested and like THGal4/ UAS-shits1 flies did not show any phasic yaw torque or landing response. Since the dopamine mutants did not show the basic yaw torque response for the test the role of dopamine in attention could not be deduced. A different paradigm would be needed to test these mutants. Not only can attention be guided through external cues, it can also be shifted endogenously (covert attention). Experiments with the windows having oscillating stripes nicely demonstrated the phenomenon of covert attention due to the production of a characteristic yaw torque pattern by the flies. However, the results were not easily quantifiable and reproducible thereby calling for a more systematic approach. Experiments with simultaneous opposing displacements of two stripes provide a promising avenue as the results from these experiments showed that the flies had a higher tendency to deliver one type of response than when the responses would be produced stochastically suggesting that attention increased this tendency. Further experiments and analysis of such experiments could shed more light on the mechanisms of covert attention in flies.}, subject = {Visuelle Aufmerksamkeit}, language = {en} } @article{BijuSchwarzLinkeetal.2011, author = {Biju, Joseph and Schwarz, Roland and Linke, Burkhard and Blom, Jochen and Becker, Anke and Claus, Heike and Goesmann, Alexander and Frosch, Matthias and M{\"u}ller, Tobias and Vogel, Ulrich and Schoen, Christoph}, title = {Virulence Evolution of the Human Pathogen Neisseria meningitidis by Recombination in the Core and Accessory Genome}, series = {PLoS One}, volume = {6}, journal = {PLoS One}, number = {4}, doi = {10.1371/journal.pone.0018441}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-137960}, pages = {e18441}, year = {2011}, abstract = {Background Neisseria meningitidis is a naturally transformable, facultative pathogen colonizing the human nasopharynx. Here, we analyze on a genome-wide level the impact of recombination on gene-complement diversity and virulence evolution in N. meningitidis. We combined comparative genome hybridization using microarrays (mCGH) and multilocus sequence typing (MLST) of 29 meningococcal isolates with computational comparison of a subset of seven meningococcal genome sequences. Principal Findings We found that lateral gene transfer of minimal mobile elements as well as prophages are major forces shaping meningococcal population structure. Extensive gene content comparison revealed novel associations of virulence with genetic elements besides the recently discovered meningococcal disease associated (MDA) island. In particular, we identified an association of virulence with a recently described canonical genomic island termed IHT-E and a differential distribution of genes encoding RTX toxin- and two-partner secretion systems among hyperinvasive and non-hyperinvasive lineages. By computationally screening also the core genome for signs of recombination, we provided evidence that about 40\% of the meningococcal core genes are affected by recombination primarily within metabolic genes as well as genes involved in DNA replication and repair. By comparison with the results of previous mCGH studies, our data indicated that genetic structuring as revealed by mCGH is stable over time and highly similar for isolates from different geographic origins. Conclusions Recombination comprising lateral transfer of entire genes as well as homologous intragenic recombination has a profound impact on meningococcal population structure and genome composition. Our data support the hypothesis that meningococcal virulence is polygenic in nature and that differences in metabolism might contribute to virulence.}, language = {en} } @article{KochCappelNockeretal.2011, author = {Koch, Oliver and Cappel, Daniel and Nocker, Monika and Jaeger, Timo and Floh{\´e}, Leopold and Sotriffer, Christoph and Selzer, Paul}, title = {Virtual screening using structure-based consensus pharmacophore models and ensemble docking based on MD-generated conformations : [From 6th German Conference on Chemoinformatics, GCC 2010, Goslar, Germany. 7-9 November 2010]}, series = {Journal of Cheminformatics}, volume = {3}, journal = {Journal of Cheminformatics}, number = {Suppl. 1}, doi = {10.1186/1758-2946-3-S1-O23}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142830}, pages = {O23}, year = {2011}, abstract = {No abstract available.}, language = {en} } @article{WeibelRaabYuetal.2011, author = {Weibel, Stephanie and Raab, Viktoria and Yu, Yong A. and Worschech, Andrea and Wang, Ena and Marincola, Francesco M. and Szalay, Aladar A.}, title = {Viral-mediated oncolysis is the most critical factor in the late-phase of the tumor regression process upon vaccinia virus infection}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68691}, year = {2011}, abstract = {Background: In principle, the elimination of malignancies by oncolytic virotherapy could proceed by different mechanisms - e.g. tumor cell specific oncolysis, destruction of the tumor vasculature or an anti-tumoral immunological response. In this study, we analyzed the contribution of these factors to elucidate the responsible mechanism for regression of human breast tumor xenografts upon colonization with an attenuated vaccinia virus (VACV). Methods: Breast tumor xenografts were analyzed 6 weeks post VACV infection (p.i.; regression phase) by immunohistochemistry and mouse-specific expression arrays. Viral-mediated oncolysis was determined by tumor growth analysis combined with microscopic studies of intratumoral virus distribution. The tumor vasculature was morphologically characterized by diameter and density measurements and vessel functionality was analyzed by lectin perfusion and extravasation studies. Immunological aspects of viral-mediated tumor regression were studied in either immune-deficient mouse strains (T-, B-, NK-cell-deficient) or upon cyclophosphamide-induced immunosuppression (MHCII+-cell depletion) in nude mice. Results: Late stage VACV-infected breast tumors showed extensive necrosis, which was highly specific to cancer cells. The tumor vasculature in infected tumor areas remained functional and the endothelial cells were not infected. However, viral colonization triggers hyperpermeability and dilatation of the tumor vessels, which resembled the activated endothelium in wounded tissue. Moreover, we demonstrated an increased expression of genes involved in leukocyte-endothelial cell interaction in VACV-infected tumors, which orchestrate perivascular inflammatory cell infiltration. The immunohistochemical analysis of infected tumors displayed intense infiltration of MHCII-positive cells and colocalization of tumor vessels with MHCII+/CD31+ vascular leukocytes. However, GI-101A tumor growth analysis upon VACV-infection in either immunosuppressed nude mice (MHCII+-cell depleted) or in immune-deficient mouse strains (T-, B-, NK-cell-deficient) revealed that neither MHCII-positive immune cells nor T-, B-, or NK cells contributed significantly to VACV-mediated tumor regression. In contrast, tumors of immunosuppressed mice showed enhanced viral spreading and tumor necrosis. Conclusions: Taken together, these results indicate that VACV-mediated oncolysis is the primary mechanism of tumor shrinkage in the late regression phase. Neither the destruction of the tumor vasculature nor the massive VACV-mediated intratumoral inflammation was a prerequisite for tumor regression. We propose that approaches to enhance viral replication and spread within the tumor microenvironment should improve therapeutical outcome.}, subject = {Virusinfektion}, language = {en} } @article{WiegeringSchickBeeretal.2011, author = {Wiegering, Verena and Schick, Judith and Beer, Meinrad and Gattenl{\"o}hner, Stefan and Girschick, Hermann and Liese, Johannes and Schlegel, Paul and Eyrich, Matthias}, title = {Varicella-zoster virus infections in immunocompromised patients - a single centre 6-years analysis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68723}, year = {2011}, abstract = {Background: Infection with varicella-zoster virus (VZV) contemporaneously with malignant disease or immunosuppression represents a particular challenge and requires individualized decisions and treatment. Although the increasing use of varicella-vaccines in the general population and rapid initiation of VZVimmunoglobulins and acyclovir in case of exposure has been beneficial for some patients, immunocompromised individuals are still at risk for unfavourable courses. Methods: In this single center, 6-year analysis we review incidence, hospitalization and complication rates of VZVinfections in our center and compare them to published data. Furthermore, we report three instructive cases. Results: Hospitalization rate of referred children with VZV-infections was 45\%, among these 17\% with malignancies and 9\% under immunosuppressive therapy. Rate of complications was not elevated in these two high-risk cohorts, but one ALL-patient died due to VZV-related complications. We report one 4-year old boy with initial diagnosis of acute lymphoblastic leukemia who showed a rapidly fatal outcome of his simultaneous varicella-infection, one 1.8-year old boy with an identical situation but a mild course of his disease, and an 8.5-year old boy with a steroiddependent nephrotic syndrome. This boy developed severe hepatic involvement during his varicella-infection but responded to immediate withdrawl of steroids and administration of acyclovir plus single-dose cidofovir after nonresponse to acyclovir after 48 h. Conclusion: Our data show that patients with malignant diseases or immunosuppressive therapy should be hospitalized and treated immediately with antiviral agents. Despite these measures the course of VZV-infections can be highly variable in these patients. We discuss aids to individual decision-making for these difficult situations.}, subject = {Varizellen-Virus}, language = {en} } @unpublished{Nassourou2011, author = {Nassourou, Mohamadou}, title = {Using Machine Learning Algorithms for Categorizing Quranic Chaptersby Major Phases of Prophet Mohammad's Messengership}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-66862}, year = {2011}, abstract = {This paper discusses the categorization of Quranic chapters by major phases of Prophet Mohammad's messengership using machine learning algorithms. First, the chapters were categorized by places of revelation using Support Vector Machine and na{\"i}ve Bayesian classifiers separately, and their results were compared to each other, as well as to the existing traditional Islamic and western orientalists classifications. The chapters were categorized into Meccan (revealed in Mecca) and Medinan (revealed in Medina). After that, chapters of each category were clustered using a kind of fuzzy-single linkage clustering approach, in order to correspond to the major phases of Prophet Mohammad's life. The major phases of the Prophet's life were manually derived from the Quranic text, as well as from the secondary Islamic literature e.g hadiths, exegesis. Previous studies on computing the places of revelation of Quranic chapters relied heavily on features extracted from existing background knowledge of the chapters. For instance, it is known that Meccan chapters contain mostly verses about faith and related problems, while Medinan ones encompass verses dealing with social issues, battles…etc. These features are by themselves insufficient as a basis for assigning the chapters to their respective places of revelation. In fact, there are exceptions, since some chapters do contain both Meccan and Medinan features. In this study, features of each category were automatically created from very few chapters, whose places of revelation have been determined through identification of historical facts and events such as battles, migration to Medina…etc. Chapters having unanimously agreed places of revelation were used as the initial training set, while the remaining chapters formed the testing set. The classification process was made recursive by regularly augmenting the training set with correctly classified chapters, in order to classify the whole testing set. Each chapter was preprocessed by removing unimportant words, stemming, and representation with vector space model. The result of this study shows that, the two classifiers have produced useable results, with an outperformance of the support vector machine classifier. This study indicates that, the proposed methodology yields encouraging results for arranging Quranic chapters by phases of Prophet Mohammad's messengership.}, subject = {Koran}, language = {en} } @article{ArltBiehlTayloretal.2011, author = {Arlt, Wiebke and Biehl, Michael and Taylor, Angela E. and Hahner, Stefanie and Lib{\´e}, Rossella and Hughes, Beverly A. and Schneider, Petra and Smith, David J. and Stiekema, Han and Krone, Nils and Porfiri, Emilio and Opocher, Giuseppe and Bertherat, Jer{\^o}me and Mantero, Franco and Allolio, Bruno and Terzolo, Massimo and Nightingale, Peter and Shackleton, Cedric H. L. and Bertagna, Xavier and Fassnacht, Martin and Stewart, Paul M.}, title = {Urine Steroid Metabolomics as a Biomarker Tool for Detecting Malignancy in Adrenal Tumors}, series = {The Journal of Clinical Endocrinology \& Metabolism}, volume = {96}, journal = {The Journal of Clinical Endocrinology \& Metabolism}, number = {12}, doi = {10.1210/jc.2011-1565}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-154682}, pages = {3775 -- 3784}, year = {2011}, abstract = {Context: Adrenal tumors have a prevalence of around 2\% in the general population. Adrenocortical carcinoma (ACC) is rare but accounts for 2-11\% of incidentally discovered adrenal masses. Differentiating ACC from adrenocortical adenoma (ACA) represents a diagnostic challenge in patients with adrenal incidentalomas, with tumor size, imaging, and even histology all providing unsatisfactory predictive values. Objective: Here we developed a novel steroid metabolomic approach, mass spectrometry-based steroid profiling followed by machine learning analysis, and examined its diagnostic value for the detection of adrenal malignancy. Design: Quantification of 32 distinct adrenal derived steroids was carried out by gas chromatography/mass spectrometry in 24-h urine samples from 102 ACA patients (age range 19-84 yr) and 45 ACC patients (20-80 yr). Underlying diagnosis was ascertained by histology and metastasis in ACC and by clinical follow-up [median duration 52 (range 26-201) months] without evidence of metastasis in ACA. Steroid excretion data were subjected to generalized matrix learning vector quantization (GMLVQ) to identify the most discriminative steroids. Results: Steroid profiling revealed a pattern of predominantly immature, early-stage steroidogenesis in ACC. GMLVQ analysis identified a subset of nine steroids that performed best in differentiating ACA from ACC. Receiver-operating characteristics analysis of GMLVQ results demonstrated sensitivity = specificity = 90\% (area under the curve = 0.97) employing all 32 steroids and sensitivity = specificity = 88\% (area under the curve = 0.96) when using only the nine most differentiating markers. Conclusions: Urine steroid metabolomics is a novel, highly sensitive, and specific biomarker tool for discriminating benign from malignant adrenal tumors, with obvious promise for the diagnostic work-up of patients with adrenal incidentalomas.}, language = {en} } @article{AllignolSchumacherWanneretal.2011, author = {Allignol, Arthur and Schumacher, Martin and Wanner, Christoph and Drechsler, Christiane and Beyersmann, Jan}, title = {Understanding competing risks: a simulation point of view}, series = {BMC Medical Research Methodology}, volume = {11}, journal = {BMC Medical Research Methodology}, number = {86}, doi = {10.1186/1471-2288-11-86}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142811}, pages = {1-13}, year = {2011}, abstract = {Background: Competing risks methodology allows for an event-specific analysis of the single components of composite time-to-event endpoints. A key feature of competing risks is that there are as many hazards as there are competing risks. This is not always well accounted for in the applied literature. Methods: We advocate a simulation point of view for understanding competing risks. The hazards are envisaged as momentary event forces. They jointly determine the event time. Their relative magnitude determines the event type. 'Empirical simulations' using data from a recent study on cardiovascular events in diabetes patients illustrate subsequent interpretation. The method avoids concerns on identifiability and plausibility known from the latent failure time approach. Results: The 'empirical simulations' served as a proof of concept. Additionally manipulating baseline hazards and treatment effects illustrated both scenarios that require greater care for interpretation and how the simulation point of view aids the interpretation. The simulation algorithm applied to real data also provides for a general tool for study planning. Conclusions: There are as many hazards as there are competing risks. All of them should be analysed. This includes estimation of baseline hazards. Study planning must equally account for these aspects.}, language = {en} } @article{GottschlichTisonMalecotetal.2011, author = {Gottschlich, G{\"u}nter and Tison, Jean-Marc and Malecot, Val{\´e}ry and Rouillard, Thomas}, title = {Typification of names in genus Hieracium based on original herbariummaterial of Alexis Jordan and Alexandre Boreau}, doi = {10.3264/FG.2011.0301}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-55533}, year = {2011}, abstract = {181 names of Hieracium species going back to original herbarium material of Alexis Jordan or Alexandre Boreau are lectotypified, 27 are neotypified. The study is based on herbarium specimens of the Universit{\´e} Catholique de Lyon (LY) and Ville d'Angers (ANG), Martrin-Donos's herbarium at the Institut Botanique de Montpellier (MPUTarn) and Arvet-Touvet's herbarium at the Mus{\´e}e d'Histoire Naturelle de Grenoble (GRM-AT). The type specimens are illustrated by photographs of the entire herbarium sheets with some detail views of flower heads and leaves. Usual nomenclatural synonyms are given for each taxon.}, subject = {Botanik}, language = {en} } @article{LeonhardtSchmittBluethgen2011, author = {Leonhardt, Sara D. and Schmitt, Thomas and Bl{\"u}thgen, Nico}, title = {Tree Resin Composition, Collection Behavior and Selective Filters Shape Chemical Profiles of Tropical Bees (Apidae: Meliponini)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69035}, year = {2011}, abstract = {The diversity of species is striking, but can be far exceeded by the chemical diversity of compounds collected, produced or used by them. Here, we relate the specificity of plant-consumer interactions to chemical diversity applying a comparative network analysis to both levels. Chemical diversity was explored for interactions between tropical stingless bees and plant resins, which bees collect for nest construction and to deter predators and microbes. Resins also function as an environmental source for terpenes that serve as appeasement allomones and protection against predators when accumulated on the bees' body surfaces. To unravel the origin of the bees' complex chemical profiles, we investigated resin collection and the processing of resin-derived terpenes. We therefore analyzed chemical networks of tree resins, foraging networks of resin collecting bees, and their acquired chemical networks. We revealed that 113 terpenes in nests of six bee species and 83 on their body surfaces comprised a subset of the 1,117 compounds found in resins from seven tree species. Sesquiterpenes were the most variable class of terpenes. Albeit widely present in tree resins, they were only found on the body surface of some species, but entirely lacking in others. Moreover, whereas the nest profile of Tetragonula melanocephala contained sesquiterpenes, its surface profile did not. Stingless bees showed a generalized collecting behavior among resin sources, and only a hitherto undescribed species-specific ''filtering'' of resin-derived terpenes can explain the variation in chemical profiles of nests and body surfaces fromdifferent species. The tight relationship between bees and tree resins of a large variety of species elucidates why the bees' surfaces contain a much higher chemodiversity than other hymenopterans.}, subject = {Stachellose Biene}, language = {en} } @article{TappeMeyerOesterleinetal.2011, author = {Tappe, Dennis and Meyer, Michael and Oesterlein, Anett and Jaye, Assan and Frosch, Matthias and Schoen, Christoph and Pantchev, Nikola}, title = {Transmission of Armillifer armillatus Ova at Snake Farm, The Gambia, West Africa}, series = {Emerging Infectious Diseases}, volume = {17}, journal = {Emerging Infectious Diseases}, number = {2}, doi = {10.3201/eid1702.101118}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142804}, pages = {251-254}, year = {2011}, abstract = {Visceral pentastomiasis caused by Armillifer armillatus larvae was diagnosed in 2 dogs in The Gambia. Parasites were subjected to PCR; phylogenetic analysis confirmed relatedness with branchiurans/crustaceans. Our investigation highlights transmission of infective A. armillatus ova to dogs and, by serologic evidence, also to 1 human, demonstrating a public health concern.}, language = {en} } @article{BinderMayBaronetal.2011, author = {Binder, Andreas and May, Denisa and Baron, Ralf and Maier, Christoph and T{\"o}lle, Thomas R. and Treede, Rolf-Detlef and Berthele, Achim and Faltraco, Frank and Flor, Herta and Gierthm{\"u}hlen, Janne and Haenisch, Sierk and Huge, Volker and Magerl, Walter and Maih{\"o}fner, Christian and Richter, Helmut and Rolke, Roman and Scherens, Andrea and {\"U}{\c{c}}eyler, Nurcan and Ufer, Mike and Wasner, Gunnar and Zhu, Jihong and Cascorbi, Ingolf}, title = {Transient Receptor Potential Channel Polymorphisms Are Associated with the Somatosensory Function in Neuropathic Pain Patients}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {3}, doi = {10.1371/journal.pone.0017387}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142782}, pages = {e17387}, year = {2011}, abstract = {Transient receptor potential channels are important mediators of thermal and mechanical stimuli and play an important role in neuropathic pain. The contribution of hereditary variants in the genes of transient receptor potential channels to neuropathic pain is unknown. We investigated the frequency of transient receptor potential ankyrin 1, transient receptor potential melastin 8 and transient receptor potential vanilloid 1 single nucleotide polymorphisms and their impact on somatosensory abnormalities in neuropathic pain patients. Within the German Research Network on Neuropathic Pain (Deutscher Forscbungsverbund Neuropathischer Schmerz) 371 neuropathic pain patients were phenotypically characterized using standardized quantitative sensory testing. Pyrosequencing was employed to determine a total of eleven single nucleotide polymorphisms in transient receptor potential channel genes of the neuropathic pain patients and a cohort of 253 German healthy volunteers. Associations of quantitative sensory testing parameters and single nucleotide polymorphisms between and within groups and subgroups, based on sensory phenotypes, were analyzed. Single nucleotide polymorphisms frequencies did not differ between both the cohorts. However, in neuropathic pain patients transient receptor potential ankyrin 1 710G>A (rs920829, E179K) was associated with the presence of paradoxical heat sensation (p=0.03), and transient receptor potential vanilloid 1 1911A>G (rs8065080, I585V) with cold hypoalgesia (p=0.0035). Two main subgroups characterized by preserved (1) and impaired (2) sensory function were identified. In subgroup 1 transient receptor potential vanilloid 1 1911A>G led to significantly less heat hyperalgesia, pinprick hyperalgesia and mechanical hypaesthesia (p=0.006, p=0.005 and p<0.001) and transient receptor potential vanilloid 1 1103C>G (rs222747, M315I) to cold hypaesthesia (p=0.002), but there was absence of associations in subgroup 2. In this study we found no evidence that genetic variants of transient receptor potential channels are involved in the expression of neuropathic pain, but transient receptor potential channel polymorphisms contributed significantly to the somatosensory abnormalities of neuropathic pain patients.}, language = {en} } @article{ArhondakisFrousiosIliopoulosetal.2011, author = {Arhondakis, Stilianos and Frousios, Kimon and Iliopoulos, Costas S. and Pissis, Solon P. and Tischler, German and Kossida, Sophia}, title = {Transcriptome map of mouse isochores}, series = {BMC Genomics}, volume = {12}, journal = {BMC Genomics}, number = {511}, doi = {10.1186/1471-2164-12-511}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142773}, pages = {1-9}, year = {2011}, abstract = {Background: The availability of fully sequenced genomes and the implementation of transcriptome technologies have increased the studies investigating the expression profiles for a variety of tissues, conditions, and species. In this study, using RNA-seq data for three distinct tissues (brain, liver, and muscle), we investigate how base composition affects mammalian gene expression, an issue of prime practical and evolutionary interest. Results: We present the transcriptome map of the mouse isochores (DNA segments with a fairly homogeneous base composition) for the three different tissues and the effects of isochores' base composition on their expression activity. Our analyses also cover the relations between the genes' expression activity and their localization in the isochore families. Conclusions: This study is the first where next-generation sequencing data are used to associate the effects of both genomic and genic compositional properties to their corresponding expression activity. Our findings confirm previous results, and further support the existence of a relationship between isochores and gene expression. This relationship corroborates that isochores are primarily a product of evolutionary adaptation rather than a simple by-product of neutral evolutionary processes.}, language = {en} } @phdthesis{DonadoGomez2011, author = {Donado Gomez, Alejandro}, title = {Trade Unions and Occupational Health and Safety}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-56076}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {This thesis comprises three essays that study the impact of trade unions on occupational health and safety (OHS). The first essay proposes a theoretical model that highlights the crucial role that unions have played throughout history in making workplaces safer. Firms traditionally oppose better health standards. Workplace safety is costly for firms but increases the average health of workers and thereby the aggregate labour supply. A laissez-faire approach in which firms set safety standards is suboptimal as workers are not fully informed of health risks associated with their jobs. Safety standards set by better-informed trade unions are output and welfare increasing. The second essay extends the model to a two-country world consisting of the capital-rich "North" and the capital-poor "South". The North has trade unions that set high OHS standards. There are no unions in the South and OHS standards are low. Trade between these two countries can imply a reduction in safety standards in the North, lowering the positive welfare effects of trade. Moreover, when trade unions are also established in the South, northern OHS standards might be further reduced. The third essay studies the impact of unions on OHS from an empirical perspective. It focuses on one component of OHS: occupational injuries. A literature summary including 25 empirical studies shows that most studies associate unions with less fatal occupational injuries. This is in perfect line with the anecdotal evidence and the basic model from the first essay. However, the literature summary also shows that most empirical studies associate unions with more nonfatal occupational injuries. This puzzling result has been explained in the literature by (1) lower underreporting in unionized workplaces, (2) unions being more able to organize hazardous workplaces, and (3) unionized workers preferring higher wages at the expense of better working conditions. Using individual-level panel data, this essay presents evidence against all these three explanations. However, it cannot reject the hypothesis that workers reduce their precautionary behaviour when they join a trade union. Hence, the puzzle seems to be due to a strong moral hazard effect. These empirical results suggest that the basic model from the first essay needs to be extended to account for this moral hazard effect.}, subject = {Arbeitsschutz}, language = {en} } @article{RauertStuehmerBargouetal.2011, author = {Rauert, H. and St{\"u}hmer, T. and Bargou, R. and Wajant, H. and Siegmund, D.}, title = {TNFR1 and TNFR2 regulate the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76092}, year = {2011}, abstract = {The huge majority of myeloma cell lines express TNFR2 while a substantial subset of them failed to show TNFR1 expression. Stimulation of TNFR1 in the TNFR1-expressing subset of MM cell lines had no or only a very mild effect on cellular viability. Surprisingly, however, TNF stimulation enhanced cell death induction by CD95L and attenuated the apoptotic effect of TRAIL. The contrasting regulation of TRAIL- and CD95L-induced cell death by TNF could be traced back to the concomitant NFjBmediated upregulation of CD95 and the antiapoptotic FLIP protein. It appeared that CD95 induction, due to its strength, overcompensated a rather moderate upregulation of FLIP so that the net effect of TNF-induced NFjB activation in the context of CD95 signaling is pro-apoptotic. TRAIL-induced cell death, however, was antagonized in response to TNF because in this context only the induction of FLIP is relevant. Stimulation of TNFR2 in myeloma cells leads to TRAF2 depletion. In line with this, we observed cell death induction in TNFR1-TNFR2-costimulated JJN3 cells. Our studies revealed that the TNF-TNF receptor system adjusts the responsiveness of the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms that generate a highly context-dependent net effect on myeloma cell survival.}, subject = {Medizin}, language = {en} } @article{RauertStuehmerBargouetal.2011, author = {Rauert, H. and St{\"u}hmer, T. and Bargou, R. and Wajant, H. and Siegmund, D.}, title = {TNFR1 and TNFR2 regulate the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms}, series = {Cell Death and Disease}, volume = {2}, journal = {Cell Death and Disease}, doi = {10.1038/cddis.2011.78}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133486}, pages = {e194}, year = {2011}, abstract = {The huge majority of myeloma cell lines express TNFR2 while a substantial subset of them failed to show TNFR1 expression. Stimulation of TNFR1 in the TNFR1-expressing subset of MM cell lines had no or only a very mild effect on cellular viability. Surprisingly, however, TNF stimulation enhanced cell death induction by CD95L and attenuated the apoptotic effect of TRAIL. The contrasting regulation of TRAIL- and CD95L-induced cell death by TNF could be traced back to the concomitant NFjBmediated upregulation of CD95 and the antiapoptotic FLIP protein. It appeared that CD95 induction, due to its strength, overcompensated a rather moderate upregulation of FLIP so that the net effect of TNF-induced NFjB activation in the context of CD95 signaling is pro-apoptotic. TRAIL-induced cell death, however, was antagonized in response to TNF because in this context only the induction of FLIP is relevant. Stimulation of TNFR2 in myeloma cells leads to TRAF2 depletion. In line with this, we observed cell death induction in TNFR1-TNFR2-costimulated JJN3 cells. Our studies revealed that the TNF-TNF receptor system adjusts the responsiveness of the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms that generate a highly context-dependent net effect on myeloma cell survival}, language = {en} } @article{WangorschButtMarketal.2011, author = {Wangorsch, Gaby and Butt, Elke and Mark, Regina and Hubertus, Katharina and Geiger, J{\"o}rg and Dandekar, Thomas and Dittrich, Marcus}, title = {Time-resolved in silico modeling of fine-tuned cAMP signaling in platelets: feedback loops, titrated phosphorylations and pharmacological modulation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69145}, year = {2011}, abstract = {Background: Hemostasis is a critical and active function of the blood mediated by platelets. Therefore, the prevention of pathological platelet aggregation is of great importance as well as of pharmaceutical and medical interest. Endogenous platelet inhibition is predominantly based on cyclic nucleotides (cAMP, cGMP) elevation and subsequent cyclic nucleotide-dependent protein kinase (PKA, PKG) activation. In turn, platelet phosphodiesterases (PDEs) and protein phosphatases counterbalance their activity. This main inhibitory pathway in human platelets is crucial for countervailing unwanted platelet activation. Consequently, the regulators of cyclic nucleotide signaling are of particular interest to pharmacology and therapeutics of atherothrombosis. Modeling of pharmacodynamics allows understanding this intricate signaling and supports the precise description of these pivotal targets for pharmacological modulation. Results: We modeled dynamically concentration-dependent responses of pathway effectors (inhibitors, activators, drug combinations) to cyclic nucleotide signaling as well as to downstream signaling events and verified resulting model predictions by experimental data. Experiments with various cAMP affecting compounds including antiplatelet drugs and their combinations revealed a high fidelity, fine-tuned cAMP signaling in platelets without crosstalk to the cGMP pathway. The model and the data provide evidence for two independent feedback loops: PKA, which is activated by elevated cAMP levels in the platelet, subsequently inhibits adenylyl cyclase (AC) but as well activates PDE3. By multi-experiment fitting, we established a comprehensive dynamic model with one predictive, optimized and validated set of parameters. Different pharmacological conditions (inhibition, activation, drug combinations, permanent and transient perturbations) are successfully tested and simulated, including statistical validation and sensitivity analysis. Downstream cyclic nucleotide signaling events target different phosphorylation sites for cAMP- and cGMP-dependent protein kinases (PKA, PKG) in the vasodilator-stimulated phosphoprotein (VASP). VASP phosphorylation as well as cAMP levels resulting from different drug strengths and combined stimulants were quantitatively modeled. These predictions were again experimentally validated. High sensitivity of the signaling pathway at low concentrations is involved in a fine-tuned balance as well as stable activation of this inhibitory cyclic nucleotide pathway. Conclusions: On the basis of experimental data, literature mining and database screening we established a dynamic in silico model of cyclic nucleotide signaling and probed its signaling sensitivity. Thoroughly validated, it successfully predicts drug combination effects on platelet function, including synergism, antagonism and regulatory loops.}, subject = {Vasodilatator-stimuliertes Phosphoprotein}, language = {en} } @article{SchwedeJonesEngstleretal.2011, author = {Schwede, Angela and Jones, Nicola and Engstler, Markus and Carrington, Mark}, title = {The VSG C-terminal domain is inaccessible to antibodies on live trypanosomes}, series = {Molecular \& Biochemical Parasitology}, volume = {175}, journal = {Molecular \& Biochemical Parasitology}, number = {2}, doi = {10.1016/j.molbiopara.2010.11.004}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142746}, pages = {201-204}, year = {2011}, abstract = {In the mammalian host, the Trypanosoma brucei cell surface is covered with a densely packed protein coat of a single protein, the variant surface glycoprotein (VSG). The VSG is believed to shield invariant surface proteins from host antibodies but there is limited information on how far antibodies can penetrate into the VSG monolayer. Here, the VSG surface coat was probed to determine whether it acts as a barrier to binding of antibodies to the membrane proximal VSG C-terminal domain. The binding of C-terminal domain antibodies to VSG221 or VSG118 was compared with antibodies recognising the cognate whole VSGs. The C-terminal VSG domain was inaccessible to antibodies on live cells but not on fixed cells. This provides further evidence that the VSG coat acts as a barrier and protects the cell from antibodies that would otherwise bind to some of the other externally disposed proteins.}, language = {en} } @article{JakubietzGruenertJakubietz2011, author = {Jakubietz, Michael G. and Gruenert, Joerg G. and Jakubietz, Rafael G.}, title = {The use of beta-tricalcium phosphate bone graft substitute in dorsally plated, comminuted distal radius fractures}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68829}, year = {2011}, abstract = {Background: Intraarticular distal radius fractures can be treated with many methods. While internal fixation with angle stable implants has become increasingly popular, the use of bone graft substitutes has also been recommended to address comminution zones and thus increase stability. Whether a combination of both methods will improve clinical outcomes was the purpose of the study Methods: The study was thus conducted as a prospective randomized clinical trial. 39 patients with unilateral, intraarticular fractures of the distal radius were included and randomized to 2 groups, one being treated with internal fixation only, while the second group received an additional bone graft substitute. Results: There was no statistical significance between both groups in functional and radiological results. The occurrence of complications did also not show statistical significance. Conclusions: No advantage of additional granular bone graft substitutes could be seen in this study. Granular bone graft substitutes do not seem to provide extra stability if dorsal angle stable implants are used. Dorsal plates have considerable complication rates such as extensor tendon ruptures and development of CRPS.}, subject = {Medizin}, language = {en} } @phdthesis{Almeling2011, author = {Almeling, Stefan}, title = {The use of aerosol-based detection systems in the quality control of drug substances}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64722}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {The work presented in this thesis was mainly targeted at exploring the capabilities of evaporation based LC detectors as well as further alternatives for the control of impurities in substances not exhibiting a suitable chromophore for UV-detection. In the course of the work carried out, several new methods for the identification, impurities control and composition testing of APIs were elaborated. An evaporation based detector that entered into the field of pharmaceutical analysis in the recent years was the Evaporative Light Scattering Detector (ELSD). However, non-reproducible spikes were reported when injecting concentrated test solutions as they are usually required for the control of impurities. The reasons, for the appearance of these spikes as well as possibilities for their avoidance were explored in a systematic study. Moreover, the dependence of the detector sensitivity on different eluent composition, eluent flow-rate and ELSD settings was investigated. In the course of the revision of the Ph.Eur. monographs for aspartic acid and alanine, a C18 reversed phase ion-pair LC method using 1 mmol/L of perfluoroheptanoic acid as an ion-pair reagent and a charged aerosol detector (CAD) was developed and fully validated for the purity control of Asp. The method was capable of separating the organic acids and major amino acids known to occur as process related impurities. With a slight modification, the method was also applicable for the purity control of Ala. Based on the developed LC-CAD method for the impurity control of alanine, a comparative study of the performance characteristics of different evaporation based LC detectors, i.e. ELSD, CAD and the recently developed Nano Quantity Analyte Detector (NQAD) was carried out. Additionally, an MS detector and qNMR were included in this study. It was found that the control of impurities in Alanine at an ICH conform level could be ensured using LC coupled to CAD, MSD and NQAD detection as well as by the use of qNMR. In terms of performance, prize and ease of use CAD and NQAD were found to be the most suitable alternatives. In terms of repeatability and sensitivity, the CAD appeared slightly superior to the NQAD. The quality of streptomycin sulfate is not sufficiently controlled by the current Ph.Eur. monograph in that an appropriate test for the control of the related substances is missing. A study was carried out to develop a C18 reversed phase ion-pair LC method using pentafluoropropionic acid as an ion-pair reagent and a CAD for the identification and control of the related substances. The developed method allowed the separation of 21 impurities from streptomycin. Moreover, coupling of the method to MS allowed the identification of the separated impurities. The method was shown to be sufficiently sensitive to control the related substances with a disregard limit of 0.1\% as it is normally applied in the Ph.Eur. for products derived from fermentation. Currently, the aescin content of horse-chestnut standardized dry extract is determined using a complex and laborious photometric determination. A more selective LC-UV assay determination for beta-aescin has been proposed for the Ph.Eur. draft monograph of horse-chestnut standardized dry extract. Possibilities were explored to further improve the LC-method using detection by CAD. It was demonstrated that by the use of a modified LC-CAD method several problems related to the differences in the UV-response of the various components contained in the active aescin fraction could be eliminated. Moreover the proposed reference standard strategy was reviewed. Eventually, it was demonstrated on the example of two different clusters of pharmacologically active peptides how low energy collision induced dissociation mass spectrometry (low energy CID-MS) can successfully be used for identification testing in pharmacopoeial monographs. In this respect, the combination of a direct confirmation of the molecular mass via the m/z-ratio of the molecule ions with structural sequence information obtained by low energy CID-MS experiments was found to deliver a higher degree of certainty of the identity of a given substance than the set of tests currently described in the monographs. A significant gain in efficiency and throughput and important reduction of the amount of sample consumed during testing were identified as being additional advantages of this approach. Taken together, it could be demonstrated on various examples how recent technological advancements in the field of analytical chemistry can contribute to improve the quality control of APIs.}, subject = {Elektronensprayionisations-Massenspektrometrie}, language = {en} } @article{AlbrechtSharmaDittrichetal.2011, author = {Albrecht, Marco and Sharma, Cynthia M. and Dittrich, Marcus T. and M{\"u}ller, Tobias and Reinhardt, Richard and Vogel, J{\"o}rg and Rudel, Thomas}, title = {The Transcriptional Landscape of Chlamydia pneumoniae}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69116}, year = {2011}, abstract = {Background: Gene function analysis of the obligate intracellular bacterium Chlamydia pneumoniae is hampered by the facts that this organism is inaccessible to genetic manipulations and not cultivable outside the host. The genomes of several strains have been sequenced; however, very little information is available on the gene structure and transcriptome of C. pneumoniae. Results: Using a differential RNA-sequencing approach with specific enrichment of primary transcripts, we defined the transcriptome of purified elementary bodies and reticulate bodies of C. pneumoniae strain CWL-029; 565 transcriptional start sites of annotated genes and novel transcripts were mapped. Analysis of adjacent genes for cotranscription revealed 246 polycistronic transcripts. In total, a distinct transcription start site or an affiliation to an operon could be assigned to 862 out of 1,074 annotated protein coding genes. Semi-quantitative analysis of mapped cDNA reads revealed significant differences for 288 genes in the RNA levels of genes isolated from elementary bodies and reticulate bodies. We have identified and in part confirmed 75 novel putative non-coding RNAs. The detailed map of transcription start sites at single nucleotide resolution allowed for the first time a comprehensive and saturating analysis of promoter consensus sequences in Chlamydia. Conclusions: The precise transcriptional landscape as a complement to the genome sequence will provide new insights into the organization, control and function of genes. Novel non-coding RNAs and identified common promoter motifs will help to understand gene regulation of this important human pathogen.}, subject = {Chlamydia pneumoniae}, language = {en} } @article{SasseSchilligDierolfetal.2011, author = {Sasse, Christoph and Schillig, Rebecca and Dierolf, Franziska and Weyler, Michael and Schneider, Sabrina and Mogavero, Selene and Rogers, David P. and Morschh{\"a}user, Joachim}, title = {The Transcription Factor Ndt80 Does Not Contribute to Mrr1-, Tac1-, and Upc2-Mediated Fluconazole Resistance in Candida albicans}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69201}, year = {2011}, abstract = {The pathogenic yeast Candida albicans can develop resistance to the widely used antifungal agent fluconazole, which inhibits ergosterol biosynthesis, by the overexpression of genes encoding multidrug efflux pumps or ergosterol biosynthesis enzymes. Zinc cluster transcription factors play a central role in the transcriptional regulation of drug resistance. Mrr1 regulates the expression of the major facilitator MDR1, Tac1 controls the expression of the ABC transporters CDR1 and CDR2, and Upc2 regulates ergosterol biosynthesis (ERG) genes. Gain-of-function mutations in these transcription factors result in constitutive overexpression of their target genes and are responsible for fluconazole resistance in many clinical C. albicans isolates. The transcription factor Ndt80 contributes to the drug-induced upregulation of CDR1 and ERG genes and also binds to the MDR1 and CDR2 promoters, suggesting that it is an important component of all major transcriptional mechanisms of fluconazole resistance. However, we found that Ndt80 is not required for the induction of MDR1 and CDR2 expression by inducing chemicals. CDR2 was even partially derepressed in ndt80D mutants, indicating that Ndt80 is a repressor of CDR2 expression. Hyperactive forms of Mrr1, Tac1, and Upc2 promoted overexpression of MDR1, CDR1/CDR2, and ERG11, respectively, with the same efficiency in the presence and absence of Ndt80. Mrr1- and Tac1-mediated fluconazole resistance was even slightly enhanced in ndt80D mutants compared to wild-type cells. These results demonstrate that Ndt80 is dispensable for the constitutive overexpression of Mrr1, Tac1, and Upc2 target genes and the increased fluconazole resistance of strains that have acquired activating mutations in these transcription factors.}, subject = {Candida albicans}, language = {en} } @article{Lin2011, author = {Lin, Hang}, title = {The Traditional Confucianism and its Contemporary Relevance}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68769}, year = {2011}, abstract = {After a century of its retreat from political and social stages in East Asia, Confucianism eventually found its revival together with the economic industrialization in the region. The awakening consciousness of the traditional Confucian values leads to a reconsideration of their implication on a modern society. Despite the criticism on the actual relevance of Confucianism and modernization, there are precious elements within the Confucian values which provide the relevance of Confucianism to the future, such as an ethic of responsibility and the understanding of the humanistic meaning of life.}, subject = {Ostasien}, language = {en} } @article{MortonVargaHornbachetal.2011, author = {Morton, Charles O. and Varga, John J. and Hornbach, Anke and Mezger, Markus and Sennefelder, Helga and Kneitz, Susanne and Kurzai, Oliver and Krappmann, Sven and Einsele, Hermann and Nierman, William C. and Rogers, Thomas R. and Loeffler, Juergen}, title = {The Temporal Dynamics of Differential Gene Expression in Aspergillus fumigatus Interacting with Human Immature Dendritic Cells In Vitro}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68958}, year = {2011}, abstract = {No abstract avDendritic cells (DC) are the most important antigen presenting cells and play a pivotal role in host immunity to infectious agents by acting as a bridge between the innate and adaptive immune systems. Monocyte-derived immature DCs (iDC) were infected with viable resting conidia of Aspergillus fumigatus (Af293) for 12 hours at an MOI of 5; cells were sampled every three hours. RNA was extracted from both organisms at each time point and hybridised to microarrays. iDC cell death increased at 6 h in the presence of A. fumigatus which coincided with fungal germ tube emergence; .80\% of conidia were associated with iDC. Over the time course A. fumigatus differentially regulated 210 genes, FunCat analysis indicated significant up-regulation of genes involved in fermentation, drug transport, pathogenesis and response to oxidative stress. Genes related to cytotoxicity were differentially regulated but the gliotoxin biosynthesis genes were down regulated over the time course, while Aspf1 was up-regulated at 9 h and 12 h. There was an up-regulation of genes in the subtelomeric regions of the genome as the interaction progressed. The genes up-regulated by iDC in the presence of A. fumigatus indicated that they were producing a pro-inflammatory response which was consistent with previous transcriptome studies of iDC interacting with A. fumigatus germ tubes. This study shows that A. fumigatus adapts to phagocytosis by iDCs by utilising genes that allow it to survive the interaction rather than just up-regulation of specific virulence genes.}, subject = {Dendritische Zelle}, language = {en} } @phdthesis{Buchholzer2011, author = {Buchholzer, Hannes}, title = {The Semismooth Newton Method for the Solution of Reactive Transport Problems Including Mineral Precipitation-Dissolution Reactions}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-65342}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {In dieser Arbeit befassen wir uns mit einem reaktiven Transportmodell mit Niederschlags-Aufl{\"o}sung Reaktionen das aus den Geowissenschaften stammt. Es besteht aus PDGs, gew{\"o}hnlichen Differentialgleichungen, algebraischen Gleichungen und Komplementarit{\"a}tsbedingungen. Nach Diskretisation dieses Modells erhalten wir eine großes nichtlineares und nichtglattes Gleichungssystem. Wir l{\"o}sen dieses System mit der semismoothen Newtonverfahren, das von Qi und Sun eingef{\"u}hrt wurde. Der Fokus dieser Arbeit ist in der Anwendung und Konvergenz dieses Algorithmus. Wir zeigen, dass dieser Algorithmus f{\"u}r dieses Problem wohldefiniert ist und sogar lokal quadratisch konvergiert gegen eine BD-regul{\"a}re L{\"o}sung. Wir befassen uns auch mit den dabei entstehenden linearen Gleichungssystemen, die sehr groß und d{\"u}nn besetzt sind, und wie sie effizient gel{\"o}st werden k{\"o}nnen. Ein wichtiger Bestandteil dieser Untersuchung ist die Beschr{\"a}nktheit einer gewissen matrixwertigen Funktion, die in einem eigenen Kapitel gezeigt wird. Als Seitenbetrachtung untersuchen wir wie die extremalen Eigenwerte (und Singul{\"a}rwerte) von gewissen PDE-Operatoren, welche in unserem diskretisierten Modell vorkommen, genau abgesch{\"a}tzt werden k{\"o}nnen.}, subject = {Komplementarit{\"a}tsproblem}, language = {en} } @phdthesis{May2011, author = {May, Frauke}, title = {The role of the (hem)ITAM-coupled receptors C-type lectin-like receptor 2 (CLEC-2) and Glycoprotein (GP) VI for platelet function: in vitro and in vivo studies in mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-65383}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Die Thrombozytenaktivierung und -adh{\"a}sion sowie die nachfolgende Thrombusbildung ist ein essentieller Prozess in der prim{\"a}ren H{\"a}mostase, der aber auch irreversible Gef{\"a}ßverschl{\"u}sse und damit Herzinfarkt oder Schlaganfall verursachen kann. Erst k{\"u}rzlich wurde beschrieben, dass der C-type lectin-like receptor 2 (CLEC-2) auf der Thrombozytenoberfl{\"a}che exprimiert wird, jedoch wurde f{\"u}r diesen Rezeptor noch keine Funktion in den Prozessen der H{\"a}mostase und Thrombose gezeigt. In der vorliegenden Arbeit wurde die Rolle von CLEC-2 in der Thrombozytenfunktion und Thrombusbildung im Mausmodel untersucht. In dem ersten Teil dieser Arbeit konnte gezeigt werden, dass die Behandlung von M{\"a}usen mit dem neu generierten monoklonalen Antik{\"o}rper INU1, der gegen murines CLEC-2 gerichtet ist, zu dem vollst{\"a}ndigen und hochspezifischen Verlust des Rezeptors in zirkulierenden Thrombozyten f{\"u}hrte, ein Prozess, der als „Immundepletion" bezeichnet wird. Die CLEC-2-defizienten Thrombozyten waren nicht mehr durch den CLEC-2-spezifischen Agonisten Rhodozytin aktivierbar, w{\"a}hrend die Aktivierung durch alle anderen getesteten Agonisten nicht beeintr{\"a}chtigt war. Dieser selektive Defekt f{\"u}hrte unter Flussbedingungen ex vivo zu stark verminderter Aggregatbildung der Thrombozyten. Außerdem zeigten in vivo-Thrombosestudien, dass die gebildeten Thromben instabil waren und vermehrt embolisierten. Infolgedessen war die CLEC-2 Defizienz mit einem deutlichen Schutz vor arterieller Thrombose verbunden. Außerdem ließ die in INU1-behandelten M{\"a}usen beobachtete variable Verl{\"a}ngerung der Blutungszeit auf einen moderaten h{\"a}mostatischen Defekt schließen. Diese Ergebnisse zeigen zum ersten Mal, dass CLEC-2 in vitro und in vivo signifikant zur Thrombusstabilit{\"a}t beitr{\"a}gt und eine essentielle Rolle in der H{\"a}mostase und arteriellen Thrombose spielt. Daher stellt CLEC-2 eine potentiell neue antithrombotische Zielstruktur dar, die in vivo inaktiviert werden kann. Diese in vivo-Herabregulierung von Thrombozytenoberfl{\"a}chenrezeptoren k{\"o}nnte einen vielversprechenden Ansatz f{\"u}r zuk{\"u}nftige antithrombotische Therapien darstellen. Der zweite Teil dieser Arbeit behandelte den Effekt einer Doppelimmundepletion der immunoreceptor tyrosine-based activation motiv (ITAM)- und hemITAM-gekoppelten Rezeptoren Glykoprotein (GP) VI und CLEC-2 auf H{\"a}mostase und Thrombose mittels einer Kombination der GPVI- beziehungsweise CLEC-2-spezifischen Antik{\"o}rper JAQ1 und INU1. Eine Einzeldepletion von GPVI oder CLEC-2 in vivo beeintr{\"a}chtigte nicht die Expression und Funktion des jeweils anderen Rezeptors. Eine gleichzeitige Behandlung mit beiden Antik{\"o}rpern f{\"u}hrte jedoch zu dem nachhaltigen Verlust der GPVI- und CLEC-2-vermittelten Signale in Thrombozyten, w{\"a}hrend andere Signalwege nicht betroffen waren. Im Gegensatz zu den Einzeldefizienzen, wiesen die GPVI/CLEC-2 doppeldefizienten M{\"a}use einen schwerwiegenden Blutungsph{\"a}notyp auf. Außerdem f{\"u}hrte die Behandlung zu einer starken Beeintr{\"a}chtigung der arteriellen Thrombusbildung, die die Effekte der Einzeldefizienzen weit {\"u}bertraf. Von Bedeutung ist auch, dass gleiche Ergebnisse in Gp6-/- M{\"a}usen gefunden wurden, die mittels INU1-Behandlung CLEC-2-depletiert wurden. Dies veranschaulicht, dass der Blutungsph{\"a}notyp nicht durch Sekund{\"a}reffekte der kombinierten Antik{\"o}rperbehandlung hervorgerufen wurde. Diese Daten deuten darauf hin, dass GPVI und CLEC-2 sowohl unabh{\"a}ngig voneinander als auch gleichzeitig in vivo von der Thrombozytenoberfl{\"a}che herabreguliert werden k{\"o}nnen und lassen unerwartete redundante Funktionen der beiden Rezeptoren in H{\"a}mostase und Thrombose erkennen. Da beide Rezeptoren, GPVI und CLEC-2, als neue antithrombotische Zielstrukturen diskutiert werden, k{\"o}nnten diese Ergebnisse wichtige Auswirkungen auf die Entwicklung von anti-GPVI oder anti-CLEC-2-basierenden Antithrombotika haben.}, subject = {Thrombozyt}, language = {en} } @article{ReichardtAlaminoSaad2011, author = {Reichardt, Joerg and Alamino, Roberto and Saad, David}, title = {The interplay between microscopic and mesoscopic structures in complex networks}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68993}, year = {2011}, abstract = {Understanding a complex network's structure holds the key to understanding its function. The physics community has contributed a multitude of methods and analyses to this cross-disciplinary endeavor. Structural features exist on both the microscopic level, resulting from differences between single node properties, and the mesoscopic level resulting from properties shared by groups of nodes. Disentangling the determinants of network structure on these different scales has remained a major, and so far unsolved, challenge. Here we show how multiscale generative probabilistic exponential random graph models combined with efficient, distributive message-passing inference techniques can be used to achieve this separation of scales, leading to improved detection accuracy of latent classes as demonstrated on benchmark problems. It sheds new light on the statistical significance of motif-distributions in neural networks and improves the link-prediction accuracy as exemplified for gene-disease associations in the highly consequential Online Mendelian Inheritance in Man database.}, subject = {Netzwerk}, language = {en} } @phdthesis{Drescher2011, author = {Drescher, Jochen}, title = {The Ecology and Population structure of the invasive Yelllow Crazy Ant Anoplolepis gracilipes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57332}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {The invasive Yellow Crazy Ant Anoplolepis gracilipes is a widespread tropical ant species which is particularly common in anthropogenically disturbed habitats in South-East Asia and the Indopacific region. Its native range is unknown, and there is little information concerning its social structure as a potential mechanism facilitating invasion as well as its ecology in one of the putative native ranges, South-East Asia. Using mitochondrial DNA sequences, I demonstrated that the majority of the current Indopacific colonies were likely introduced from South-East Asian populations, which in turn may have been introduced much earlier from a yet unidentified native range. By conducting behavioral, genetic and chemical analyses, I found that A. gracilipes supercolonies contain closely related individuals, thus resembling enlarged versions of monogynous, polydomous colonies of other ant species. Furthermore, mutually aggressive A. gracilipes supercolonies were highly differentiated both genetically and chemically, suggesting limited or even absent gene flow between supercolonies. Intranidal mating and colony-budding are most likely the predominant, if not the exclusive mode of reproduction and dispersal strategy of A. gracilipes. Consequently, a positive feedback between genetic, chemical and behavioral traits may further enhance supercolony differentiation though genetic drift and neutral evolution. This potential scenario led to the hypothesis that absent gene flow between different A. gracilipes supercolonies may drive them towards different evolutionary pathways, possibly including speciation. Thus, I examined one potential way by which gene flow between supercolonies of an ant species without nuptial flights may be maintained, i.e. the immigration of sexuals into foreign supercolonies. The results suggest that this option of maintaining gene flow between different supercolonies is likely impaired by severe aggression of workers towards allocolonial sexuals. Moreover, breeding experiments involving males and queens from different supercolonies suggest that A. gracilipes supercolonies may already be on the verge of reproductive isolation, which might lead to the diversification of A. gracilipes into different species. Regarding the ecological consequences of its potential introduction to NE-Borneo, I could show that A. gracilipes supercolonies may affect the local ant fauna. The ant community within supercolonies was less diverse and differed in species composition from areas outside supercolonies. My data suggest that the ecological dominance of A. gracilipes within local ant communities was facilitated by monopolization of food sources within its supercolony territory, achieved by a combination of rapid recruitment, numerical dominance and pronounced interspecific aggression. A. gracilipes' distribution is almost exclusively limited to anthropogenically altered habitat, such as residential and agricultural areas. The rate at which habitat conversion takes place in NE-Borneo will provide A. gracilipes with a rapidly increasing abundance of suitable habitats, thus potentially entailing significant population growth. An potentially increasing population size and ecological dominance, however, are not features that are limited to invasive alien species, but may also occur in native species that become 'pests' in an increasing abundance of anthropogenically altered habitat. Lastly, I detected several ant guests in supercolonies of A. gracilipes. I subsequently describe the relationship between one of them (the cricket Myrmecophilus pallidithorax) and its ant host. By conducting behavioral bioassays and analyses of cuticular hydrocarbon (CHC) profiles, I revealed that although M. pallidithorax is attacked and consumed by A. gracilipes whenever possible, it may evade aggression from its host by a combination of supreme agility and, possibly, chemical deception. This thesis adds to our general understanding of biological invasions by contributing species-specific data on a previously understudied invasive organism, the Yellow Crazy Ant Anoplolepis gracilipes. Introductions which may have occurred a long time ago may make it difficult to determine whether a given species is an introduced invader or a native pest species, as both may have pronounced ecological effects in native species communities. Furthermore, this thesis suggests that supercolonialism in invasive ants may not be an evolutionary dead end, but that it may possibly give rise to new species due to reproductive boundaries between supercolonies evoked by peculiar mating and dispersal strategies.}, subject = {Dem{\"o}kologie}, language = {en} } @phdthesis{Hsieh2011, author = {Hsieh, Samuel Yu-Lung}, title = {The diversity and ecology of the spider communities of European beech canopy}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-66966}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Ein wesentliches Ziel {\"o}kologischer Forschung ist es, die Frage zu beantworten, wie Arten koexistieren k{\"o}nnen und die biologische Vielfalt erhalten bleibt. Um zu verstehen, wie dabei Gemeinschaften in unterschiedlichen r{\"a}umlich-zeitlichen Dimensionen interagieren, um die biologische Vielfalt zu erhalten, ist ein umfassendes prozessorientiertes Wissen erforderlich. Demzufolge konzentrierte sich meine Studie im Wesentlichen auf die Biodiversit{\"a}t und die sie beeinflussenden raum-zeitlichen {\"o}kologischen Prozesse. Vergleicht man die {\"A}hnlich- bzw. Un{\"a}hnlichkeit der in verschieden alten Best{\"a}nden lebenden Spinnengemeinschaften der Buchen (Fagus sylvatica L.), dann zeigt sich, dass die {\"a}lteste Baumkohorte offensichtlich einzigartige Ressourcen besitzt, welche die Zusammensetzung der Spinnengemeinschaften deutlich pr{\"a}gen. {\"U}ber das Jahr hin zeigten die Spinnengemeinschaften trotz der jahreszeitlich unterschiedlich {\"o}kologischen Randbedingungen eine sich wiederholende, vorhersehbare Dynamik. Der Vergleich {\"u}ber die Jahre ergab, dass das "Neutrale Modell" und das "Nischen-Modell" gleichzeitig funktionieren k{\"o}nnen. Beide sind notwendig, um die Dynamik der in den Buchenkronen der verschiedenen Altersklassen lebenden Spinnengemeinschaften vollst{\"a}ndig erkl{\"a}ren zu k{\"o}nnen.}, subject = {Spinnen}, language = {en} } @phdthesis{Mishra2011, author = {Mishra, Dushyant}, title = {The content of olfactory memory in larval Drosophila}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-66316}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {An animal depends heavily on its sense of smell and its ability to form olfactory associations as this is crucial for its survival. This thesis studies in two parts about such associative olfactory learning in larval Drosophila. The first part deals with different aspects of odour processing while the second part is concerned with aspects related to memory and learning. Chapter I.1 highlights how odour intensities could be integrated into the olfactory percept of larval Drosophila. I first describe the dose-effect curves of learnability across odour intensities for different odours and then choose odour intensities from these curves such that larvae are trained at intermediate odour intensity, but are tested for retention with either that trained intermediate odour intensity, or with respectively HIGHer or LOWer intensities. I observe a specificity of retention for the trained intensity for all the odours used. Further I compare these findings with the case of adult Drosophila and propose a circuit level model of how such intensity coding comes about. Such intensity specificity of learning adds to appreciate the richness in 'content' of olfactory memory traces, and to define the demands on computational models of olfaction and olfactory learning. Chapter I.2 provides a behaviour-based estimate of odour similarity using four different types of experiments to yield a combined, task-independent estimate of perceived difference between odour-pairs. Further comparison of these perceived differences to published measures of physico- chemical difference reveals a weak correlation. Notable exceptions to this correlation are 3-octanol and benzaldehyde. Chapter I.3 shows for two odours (3-octanol and 1-octene-3-ol) that perceptual differences between these odours can either be ignored after non-discriminative training (generalization), or accentuated by odour-specific reinforcement (discrimination). Anosmic Or83b1 mutants have lost these faculties, indicating that this adaptive adjustment is taking place downstream of Or83b expressing sensory neurons. Chapter II.1 of this thesis deals with food supplementation with dried roots of Rhodiola rosea. This dose-dependently improves odour- reward associative function in larval Drosophila. Supplementing fly food with commercially available tablets or extracts, however, does not have a 'cognitive enhancing' effect, potentially enabling us to differentiate between the effective substances in the root versus these preparations. Thus Drosophila as a genetically tractable study case should now allow accelerated analyses of the molecular mechanism(s) that underlie this 'cognitive enhancement' conveyed by Rhodiola rosea. Chapter II.2 describes the role of Synapsin, an evolutionarily conserved presynaptic phosphoprotein using a combined behavioural and genetic approach and asks where and how, this protein affects functions in associative plasticity of larval Drosophila. This study shows that a Synapsin-dependent memory trace can be pinpointed to the mushroom bodies, a 'cortical' brain region of the insects. On the molecular level, data in this study assign Synapsin as a behaviourally- relevant effector of the AC-cAMP-PKA cascade.}, subject = {Drosophila}, language = {en} } @article{WobserGaiglTrautmann2011, author = {Wobser, Marion and Gaigl, Zeno and Trautmann, Axel}, title = {The concept of "compartment allergy": prilocaine injected into different skin layers}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68679}, year = {2011}, abstract = {We herein present a patient with delayed-type allergic hypersensitivity against prilocaine leading to spreading eczematous dermatitis after subcutaneous injections for local anesthesia with prilocaine. Prilocaine allergy was proven by positive skin testing and subcutaneous provocation, whereas the evaluation of other local anesthetics - among them lidocaine, articaine and mepivacaine - did not exhibit any evidence for cross-reactivity. Interestingly, our patient repeatedly tolerated strictly deep subcutaneous injection of prilocaine in provocation testing while patch and superficial subcutaneous application mounted strong allergic responses. We hypothesize, that lower DC density in deeper cutaneous compartments and/or different DC subsets exhibiting distinct functional immunomodulatory properties in the various layers of the skin may confer to the observed absence of clinical reactivity against prilocaine after deep subcutaneous injection. The term compartment allergy indicates that the route of allergen administration together with the targeted immunologic environment orchestrates on the immunologic outcome: overt T-cell mediated allergy or clinical tolerance.}, subject = {Medizin}, language = {en} } @article{HendriksmaHaertelSteffanDewenter2011, author = {Hendriksma, Harmen P. and H{\"a}rtel, Stephan and Steffan-Dewenter, Ingolf}, title = {Testing Pollen of Single and Stacked Insect-Resistant Bt-Maize on In vitro Reared Honey Bee Larvae}, series = {PLoS One}, volume = {6}, journal = {PLoS One}, number = {12}, doi = {10.1371/journal.pone.0028174}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-137803}, pages = {e28174}, year = {2011}, abstract = {The ecologically and economic important honey bee (Apis mellifera) is a key non-target arthropod species in environmental risk assessment (ERA) of genetically modified (GM) crops. Honey bee larvae are directly exposed to transgenic products by the consumption of GM pollen. But most ERA studies only consider responses of adult bees, although Bt-proteins primarily affect the larval phases of target organisms. We adopted an in vitro larvae rearing system, to assess lethal and sublethal effects of Bt-pollen consumption in a standardized eco-toxicological bioassay. The effects of pollen from two Bt-maize cultivars, one expressing a single and the other a total of three Bt-proteins, on the survival and prepupae weight of honey bee larvae were analyzed. The control treatments included pollen from three non-transgenic maize varieties and of Heliconia rostrata. Three days old larvae were fed the realistic exposure dose of 2 mg pollen within the semi-artificial diet. The larvae were monitored over 120 h, until the prepupal stage, where larvae terminate feeding and growing. Neither single nor stacked Bt-maize pollen showed an adverse effect on larval survival and the prepupal weight. In contrast, feeding of H. rostrata pollen caused significant toxic effects. The results of this study indicate that pollen of the tested Bt-varieties does not harm the development of in vitro reared A. mellifera larvae. To sustain the ecosystem service of pollination, Bt-impact on A. mellifera should always be a crucial part of regulatory biosafety assessments. We suggest that our approach of feeding GM pollen on in vitro reared honey bee larvae is well suited of becoming a standard bioassay in regulatory risk assessments schemes of GM crops.}, language = {en} } @article{ThormannRaupachWagneretal.2011, author = {Thormann, Birthe and Raupach, Michael J. and Wagner, Thomas and W{\"a}gele, Johann W. and Peters, Marcell K.}, title = {Testing a Short Nuclear Marker for Inferring Staphylinid Beetle Diversity in an African Tropical Rain Forest}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {3}, doi = {10.1371/journal.pone.0018101}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142666}, pages = {e18101}, year = {2011}, abstract = {Background: The use of DNA based methods for assessing biodiversity has become increasingly common during the last years. Especially in speciose biomes as tropical rain forests and/or in hyperdiverse or understudied taxa they may efficiently complement morphological approaches. The most successful molecular approach in this field is DNA barcoding based on cytochrome c oxidase I (COI) marker, but other markers are used as well. Whereas most studies aim at identifying or describing species, there are only few attempts to use DNA markers for inventorying all animal species found in environmental samples to describe variations of biodiversity patterns. Methodology/Principal Findings: In this study, an analysis of the nuclear D3 region of the 28S rRNA gene to delimit species-like units is compared to results based on distinction of morphospecies. Data derived from both approaches are used to assess diversity and composition of staphylinid beetle communities of a Guineo-Congolian rain forest in Kenya. Beetles were collected with a standardized sampling design across six transects in primary and secondary forests using pitfall traps. Sequences could be obtained of 99\% of all individuals. In total, 76 molecular operational taxonomic units (MOTUs) were found in contrast to 70 discernible morphospecies. Despite this difference both approaches revealed highly similar biodiversity patterns, with species richness being equal in primary and secondary forests, but with divergent species communities in different habitats. The D3-MOTU approach proved to be an efficient tool for biodiversity analyses. Conclusions/Significance: Our data illustrate that the use of MOTUs as a proxy for species can provide an alternative to morphospecies identification for the analysis of changes in community structure of hyperdiverse insect taxa. The efficient amplification of the D3-marker and the ability of the D3-MOTUs to reveal similar biodiversity patterns as analyses of morphospecies recommend its use in future molecular studies on biodiversity.}, language = {en} } @article{UeceylerHaeuserSommer2011, author = {{\"U}ceyler, Nurcan and H{\"a}user, Winfried and Sommer, Claudia}, title = {Systematic review with meta-analysis: Cytokines in fibromyalgia syndrome}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69189}, year = {2011}, abstract = {Background: To perform a systematic review and meta-analysis on cytokine levels in patients with fibromyalgia syndrome (FMS). Methods: Through December 2010 we systematically reviewed the databases PubMed, MEDLINE, and PsycINFO and screened the reference lists of 22 review articles for suitable original articles. Original articles investigating cytokines in patients with FMS were included. Data were extracted by two independent authors. Differences of the cytokine levels of FMS patients and controls were summarized by standardized mean differences (SMD) using a random effects model. Study quality was assessed applying methodological scores: modified Center of Evidence Based Medicine, Newcastle-Ottawa-Scale, and W{\"u}rzburg Methodological Quality Score. Results: Twenty-five articles were included investigating 1255 FMS patients and 800 healthy controls. Data of 13/25 studies entered meta-analysis. The overall methodological quality of studies was low. The results of the majority of studies were not comparable because methods, investigated material, and investigated target cytokines differed. Systematic review of the selected 25 articles revealed that FMS patients had higher serum levels of interleukin (IL)-1 receptor antagonist, IL-6, and IL-8, and higher plasma levels of IL-8. Meta-analysis of eligible studies showed that FMS patients had higher plasma IL-6 levels compared to controls (SMD = -0.34 [-0.64, -0.03] 95\% CI; p = 0.03). The majority of investigated cytokines were not different between patients and controls. Conclusions: The pathophysiological role of cytokines in FMS is still unclear. Studies of higher quality and with higher numbers of subjects are needed.}, subject = {Fibromyalgie}, language = {en} } @phdthesis{Stieb2011, author = {Stieb, Sara Mae}, title = {Synaptic plasticity in visual and olfactory brain centers of the desert ant Cataglyphis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-85584}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {W{\"u}stenameisen der Gattung Cataglyphis wurden zu Modellsystemen bei der Erforschung der Navigationsmechanismen der Insekten. Ein altersabh{\"a}ngiger Polyethismus trennt deren Kolonien in Innendienst-Arbeiterinnen und kurzlebige lichtausgesetzte Fourageure. Nachdem die Ameisen in strukturlosem oder strukturiertem Gel{\"a}nde bis zu mehrere hundert Meter weite Distanzen zur{\"u}ckgelegt haben, k{\"o}nnen sie pr{\"a}zise zu ihrer oft unauff{\"a}lligen Nest{\"o}ffnung zur{\"u}ckzukehren. Um diese enorme Navigationsleistung zu vollbringen, bedienen sich die Ameisen der sogenannten Pfadintegration, welche die Informationen aus einem Polarisationskompass und einem Entfernungsmesser verrechnet; des Weiteren orientieren sie sich an Landmarken und nutzen olfaktorische Signale. Im Fokus dieser Arbeit steht C. fortis, welche in Salzpfannen des westlichen Nordafrikas endemisch ist - einem Gebiet, welches vollst{\"a}ndig von anderen Cataglyphis Arten gemieden wird. Die Tatsache, dass Cataglyphis eine hohe Verhaltensflexibilit{\"a}t aufweist, welche mit sich drastisch {\"a}ndernden sensorischen Anforderungen verbunden ist, macht diese Ameisen zu besonders interessanten Studienobjekten bei der Erforschung synaptischer Plastizit{\"a}t visueller und olfaktorischer Gehirnzentren. Diese Arbeit fokussiert auf plastische {\"A}nderungen in den Pilzk{\"o}rpern (PK) - sensorischen Integrationszentren, die mutmaßlich an Lern- und Erinnerungsprozessen, und auch vermutlich am Prozess des Landmarkenlernens beteiligt sind - und auf plastische {\"A}nderungen in den synaptischen Komplexen des Lateralen Akzessorischen Lobus (LAL) - einer bekannten Relaisstation in der Polarisations-Leitungsbahn. Um die strukturelle synaptische Plastizit{\"a}t der PK in C. fortis zu quantifizieren, wurden mithilfe immunozytochemischer F{\"a}rbungen die pr{\"a}- und postsynaptischen Profile klar ausgepr{\"a}gter synaptischer Komplexe (Mikroglomeruli, MG) der visuellen Region (Kragen) und der olfaktorischen Region (Lippe) der PK-Kelche visualisiert. Die Ergebnisse legen dar, dass eine Volumenzunahme der PK-Kelche w{\"a}hrend des {\"U}bergangs von Innendiensttieren zu Fourageuren von einer Abnahme der MG-Anzahl im Kragen und, mit einem geringeren Anteil, in der Lippe - dieser Effekt wird als Pruning bezeichnet - und einem gleichzeitigen Auswachsen an Dendriten PK-intrinsischer Kenyonzellen begleitet wird. Im Dunkeln gehaltene Tiere unterschiedlichen Alters zeigen nach Lichtaussetzung den gleichen Effekt und im Dunkel gehaltene, den Fourageuren altersm{\"a}ßig angepasste Tiere weisen eine vergleichbare MG-Anzahl im Kragen auf wie Innendiensttiere. Diese Ergebnisse deuten darauf hin, dass die immense strukturelle synaptische Plastizit{\"a}t in der Kragenregion der PK-Kelche haupts{\"a}chlich durch visuelle Erfahrungen ausgel{\"o}st wird und nicht ausschließlich mit Hilfe eines internen Programms abgespielt wird. Ameisen, welche unter Laborbedingungen bis zu einem Jahr alt wurden, zeigen eine vergleichbare Plastizit{\"a}t. Dies deutet darauf hin, dass das System {\"u}ber die ganze Lebensspanne eines Individuums flexibel bleibt. Erfahrene Fourageure wurden in Dunkelheit zur{\"u}ckgef{\"u}hrt, um zu untersuchen, ob die lichtausgel{\"o}ste synaptische Umstrukturierung reversibel ist, doch ihre PK zeigen nur einige die Zur{\"u}ckf{\"u}hrung widerspiegelnde Plastizit{\"a}tsauspr{\"a}gungen, besonders eine {\"A}nderung der pr{\"a}synaptischen Synapsinexprimierung. Mithilfe immunozytochemischer F{\"a}rbungen, konfokaler Mikroskopie und 3D-Rekonstruktionen wurden die pr{\"a}- und postsynaptischen Strukturen synaptischer Komplexe des LAL in C. fortis analysiert und potentielle strukturelle {\"A}nderungen bei Innendiensttieren und Fourageuren quantifiziert. Die Ergebnisse zeigen, dass diese Komplexe aus postsynaptischen, in einer zentralen Region angeordneten Forts{\"a}tzen bestehen, welche umringt sind von einem pr{\"a}synaptischen kelchartigen Profil. Eingehende und ausgehende Trakte wurden durch Farbstoffinjektionen identifiziert: Projektionsneurone des Anterioren Optischen Tuberkels kontaktieren Neurone, welche in den Zentralkomplex ziehen. Der Verhaltens{\"u}bergang wird von einer Zunahme an synaptischen Komplexen um ~13\% begleitet. Dieser Zuwachs suggeriert eine Art Kalibrierungsprozess in diesen potentiell kr{\"a}ftigen synaptischen Kontakten, welche vermutlich eine schnelle und belastbare Signal{\"u}bertragung in der Polarisationsbahn liefern. Die Analyse von im Freiland aufgenommener Verhaltenweisen von C. fortis enth{\"u}llen, dass die Ameisen, bevor sie mit ihrer Fouragiert{\"a}tigkeit anfangen, bis zu zwei Tage lang in unmittelbarer N{\"a}he des Nestes Entdeckungsl{\"a}ufe unternehmen, welche Pirouetten {\"a}hnliche Drehungen beinhalten. W{\"a}hrend dieser Entdeckungsl{\"a}ufe sammeln die Ameisen Lichterfahrung und assoziieren m{\"o}glicherweise den Nesteingang mit spezifischen Landmarken oder werden anderen visuellen Informationen, wie denen des Polarisationsmusters, ausgesetzt und adaptieren begleitend ihre neuronalen Netzwerke an die bevorstehende Herausforderung. Dar{\"u}ber hinaus k{\"o}nnten die Pirouetten einer Stimulation der an der Polarisationsbahn beteiligten neuronalen Netzwerke dienen. Videoanalysen legen dar, dass Lichtaussetzung nach drei Tagen die Bewegungsaktivit{\"a}t der Ameisen heraufsetzt. Die Tatsache, dass die neuronale Umstrukturierung in visuellen Zentren wie auch die Ver{\"a}nderungen im Verhalten im selben Zeitrahmen ablaufen, deutet darauf hin, dass ein Zusammenhang zwischen struktureller synaptischer Plastizit{\"a}t und dem Verhaltens{\"u}bergang von der Innendienst- zur Fouragierphase bestehen k{\"o}nnte. Cataglyphis besitzen hervorragende visuelle Navigationsf{\"a}higkeiten, doch sie nutzen zudem olfaktorische Signale, um das Nest oder die Futterquelle aufzusp{\"u}ren. Mithilfe konfokaler Mikroskopie und 3D-Rekonstruktionen wurden potentielle Anpassungen der prim{\"a}ren olfaktorischen Gehirnzentren untersucht, indem die Anzahl, Gr{\"o}ße und r{\"a}umliche Anordnung olfaktorischer Glomeruli im Antennallobus von C. fortis, C. albicans, C. bicolor, C. rubra, und C. noda verglichen wurde. Arbeiterinnen aller Cataglyphis-Arten haben eine geringere Glomeruli-Anzahl im Vergleich zu denen der mehr olfaktorisch-orientierten Formica Arten - einer Gattung nah verwandt mit Cataglyphis - und denen schon bekannter olfaktorisch-orientierter Ameisenarten. C. fortis hat die geringste Anzahl an Glomeruli im Vergleich zu allen anderen Cataglyphis-Arten und besitzt einen vergr{\"o}ßerten Glomerulus, der nahe dem Eingang des Antennennerves lokalisiert ist. C. fortis M{\"a}nnchen besitzen eine signifikant geringere Glomeruli-Anzahl im Vergleich zu Arbeiterinnen und K{\"o}niginnen und haben einen hervorstechenden M{\"a}nnchen-spezifischen Makroglomerulus, welcher wahrscheinlich an der Pheromon-Kommunikation beteiligt ist. Die Verhaltensrelevanz des vergr{\"o}ßerten Glomerulus der Arbeiterinnen bleibt schwer fassbar. Die Tatsache, dass C. fortis Mikrohabitate bewohnt, welche von allen anderen Cataglyphis Arten gemieden werden, legt nahe, dass extreme {\"o}kologische Bedingungen nicht nur zu Anpassungen der visuellen F{\"a}higkeiten, sondern auch des olfaktorischen Systems gef{\"u}hrt haben. Die vorliegende Arbeit veranschaulicht, dass Cataglyphis ein exzellenter Kandidat ist bei der Erforschung neuronaler Mechanismen, welche Navigationsfunktionalit{\"a}ten zugrundeliegen, und bei der Erforschung neuronaler Plastizit{\"a}t, welche verkn{\"u}pft ist mit der lebenslangen Flexibilit{\"a}t eines individuellen Verhaltensrepertoires.}, subject = {Neuroethologie}, language = {en} } @phdthesis{Subota2011, author = {Subota, Ines}, title = {Switches in trypanosome differentiation: ALBA proteins acting on post-transcriptional mRNA control}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-85707}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Trypanosoma brucei is a digenetic eukaryotic parasite that develops in different tissues of a mammalian host and a tsetse fly. It is responsible for sleeping sickness in sub-saharan Africa. The parasite cycle involves more than nine developmental stages that can be clearly distinguished by their general morphology, their metabolism and the relative positioning of their DNA-containing organelles. During their development, trypanosomes remain exclusively extracellular and encounter changing environments with different physico-chemical properties (nutritional availability, viscosity, temperature, etc.). It has been proposed that trypanosomes use their flagellum as a sensing organelle, in agreement with the established role of structurally-related cilia in metazoa and ciliates. Recognition of environmental triggers is presumed to be at the initiation of differentiation events, leading to the parasite stage that is the best suited to the new environment. These changes are achieved by the modification of gene expression programmes, mostly underlying post-transcriptional control of mRNA transcripts. We first demonstrate that the RNA-binding proteins ALBA3/4 are involved in specific differentiation processes during the parasite development in the fly. They are cytosolic and expressed throughout the parasite cycle with the exception of the stages found in the tsetse fly proventriculus, as shown by both immunofluorescence and live cell analysis upon endogenous tagging with YFP. Knock-down of both proteins in the developmental stage preceding these forms leads to striking modifications: cell elongation, cell cycle arrest and relocalization of the nucleus in a posterior position, all typical of processes acting in parasites found in the proventriculus region. When ALBA3 is over-expressed from an exogenous copy during infection, it interferes with the relocalization of the nucleus in proventricular parasites. This is not observed for ALBA4 over-expression that does not visibly impede differentiation. Both ALBA3/4 proteins react to starvation conditions by accumulating in cytoplasmic stress granules together with DHH1, a recognized RNA-binding protein. ALBA3/4 proteins also partially colocalize with granules formed by polyA+ RNA in these conditions. We propose that ALBA are involved in trypanosome differentiation processes where they control a subset of developmentally regulated transcripts. These processes involving ALBA3/4 are likely to result from the specific activation of sensing pathways. In the second part of the thesis, we identify novel flagellar proteins that could act in sensing mechanisms. Several protein candidates were selected from a proteomic analysis of intact flagella performed in the host laboratory. This work validates their flagellar localization with high success (85\% of the proteins examined) and defines multiple different patterns of protein distribution in the flagellum. Two proteins are analyzed during development, one of them showing down-regulation in proventricular stages. The functional analysis of one novel flagellar membrane protein reveals its rapid dynamics within the flagellum but does not yield a visible phenotype in culture. This is coherent with sensory function that might not be needed in stable culture conditions, but could be required in natural conditions during development. In conclusion, this work adds new pieces to the puzzle of identifying molecular switches involved in developmental mRNA control and environmental sensing in trypanosome stages in the tsetse fly.}, subject = {Trypanosoma brucei}, language = {en} } @article{WaldholmWangBrodinetal.2011, author = {Waldholm, Johan and Wang, Zhi and Brodin, David and Tyagi, Anu and Yu, Simei and Theopold, Ulrich and {\"O}stlund Farrants, Ann Kristin and Visa, Neus}, title = {SWI/SNF regulates the alternative processing of a specific subset of pre-mRNAs in \(Drosophila\) \(melanogaster\)}, series = {BMC Molecular Biology}, volume = {12}, journal = {BMC Molecular Biology}, number = {46}, doi = {10.1186/1471-2199-12-46}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142613}, pages = {1-12}, year = {2011}, abstract = {Background: The SWI/SNF chromatin remodeling factors have the ability to remodel nucleosomes and play essential roles in key developmental processes. SWI/SNF complexes contain one subunit with ATPase activity, which in Drosophila melanogaster is called Brahma (Brm). The regulatory activities of SWI/SNF have been attributed to its influence on chromatin structure and transcription regulation, but recent observations have revealed that the levels of Brm affect the relative abundances of transcripts that are formed by alternative splicing and/or polyadenylation of the same pre-mRNA. Results: We have investigated whether the function of Brm in pre-mRNA processing in Drosophila melanogaster is mediated by Brm alone or by the SWI/SNF complex. We have analyzed the effects of depleting individual SWI/SNF subunits on pre-mRNA processing throughout the genome, and we have identified a subset of transcripts that are affected by depletion of the SWI/SNF core subunits Brm, Snr1 or Mor. The fact that depletion of different subunits targets a subset of common transcripts suggests that the SWI/SNF complex is responsible for the effects observed on pre-mRNA processing when knocking down Brm. We have also depleted Brm in larvae and we have shown that the levels of SWI/SNF affect the pre-mRNA processing outcome in vivo. Conclusions: We have shown that SWI/SNF can modulate alternative pre-mRNA processing, not only in cultured cells but also in vivo. The effect is restricted to and specific for a subset of transcripts. Our results provide novel insights into the mechanisms by which SWI/SNF regulates transcript diversity and proteomic diversity in higher eukaryotes.}, language = {en} } @article{PhamHelluyKleinschnitzetal.2011, author = {Pham, Mirko and Helluy, Xavier and Kleinschnitz, Christoph and Kraft, Peter and Bartsch, Andreas J. and Jakob, Peter and Nieswandt, Bernhard and Bendszus, Martin and Guido, Stoll}, title = {Sustained Reperfusion after Blockade of Glycoprotein-Receptor-Ib in Focal Cerebral Ischemia: An MRI Study at 17.6 Tesla}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {4}, doi = {10.1371/journal.pone.0018386}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142608}, pages = {e18386}, year = {2011}, abstract = {Background: Inhibition of early platelet adhesion by blockade of glycoprotein-IB (GPIb) protects mice from ischemic stroke. To elucidate underlying mechanisms in-vivo, infarct development was followed by ultra-high field MRI at 17.6 Tesla. Methods: Cerebral infarction was induced by transient-middle-cerebral-artery-occlusion (tMCAO) for 1 hour in C57/BL6 control mice (N = 10) and mice treated with 100 mg Fab-fragments of the GPIb blocking antibody p0p/B 1 h after tMCAO (N = 10). To control for the effect of reperfusion, additional mice underwent permanent occlusion and received anti-GPIb treatment (N = 6; pMCAO) or remained without treatment (N = 3; pMCAO). MRI 2 h and 24 h after MCAO measured cerebral-blood-flow (CBF) by continuous arterial-spin labelling, the apparent-diffusion-coefficient (ADC), quantitative-T2 and T2-weighted imaging. All images were registered to a standard mouse brain MRI atlas and statistically analysed voxel-wise, and by cortico-subcortical ROI analysis. Results: Anti-GPIb treatment led to a relative increase of postischemic CBF vs. controls in the cortical territory of the MCA (2 h: 44.2 +/- 6.9 ml/100g/min versus 24 h: 60.5 +/- 8.4; p = 0.0012, F((1,18)) = 14.63) after tMCAO. Subcortical CBF 2 h after tMCAO was higher in anti-GPIb treated animals (45.3 +/- 5.9 vs. controls: 33.6 +/- 4.3; p = 0.04). In both regions, CBF findings were clearly related to a lower probability of infarction (Cortex/Subcortex of treated group: 35\%/65\% vs. controls: 95\%/100\%) and improved quantitative-T2 and ADC. After pMCAO, anti-GPIb treated mice developed similar infarcts preceded by severe irreversible hypoperfusion as controls after tMCAO indicating dependency of stroke protection on reperfusion. Conclusion: Blockade of platelet adhesion by anti-GPIb-Fab-fragments results in substantially improved CBF early during reperfusion. This finding was in exact spatial correspondence with the prevention of cerebral infarction and indicates in-vivo an increased patency of the microcirculation. Thus, progression of infarction during early ischemia and reperfusion can be mitigated by anti-platelet treatment.}, language = {en} } @phdthesis{Joseph2011, author = {Joseph, Julie}, title = {Studying the role of Th17 cells in autoimmune diabetes and generation of a beta cell reporter mouse by lentiviral transgenesis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-66571}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Type 1 diabetes affects around 0.5\% of the population in developed countries and the incidence rates have been rising over the years. The destruction of beta cells is irreversible and the current therapy available to patients only manages the symptoms and does not prevent the associated pathological manifestations. The patients need lifelong therapy and intensive research is being carried out to identify ways to eliminate autoimmune responses directed against pancreatic beta cells and to replace or regenerate beta cells. The work presented herein aimed at analyzing the role of the Th17 T cell subset, characterized by secretion of the pro- inflammatory cytokine IL-17A, in autoimmune diabetes and also at generating a beta cell reporter mouse line in the NOD background, the most widely- used mouse model for type 1 diabetes. We generated IL- 17A knockdown (KD) NOD mice, using RNAi in combination with lentiviral transgenesis. We analyzed diabetes frequency in IL-17A deficient mice and found that the loss of IL-17A did not protect the transgenic mice from diabetes. Based on these observations, we believe that Th17 cells do not play a critical role in type 1 diabetes through the IL-17A pathway, though they might still be involved in the disease process through alternate pathways. We also generated NOD and NOD-SCID mice with a transgene that drives the beta cell specific expression of a luciferase reporter gene. We used a lentiviral construct, which combined a luciferase sequence and a short- hairpin RNA (shRNA) expression cassette, allowing gene- knockdown under the beta cell specific rat insulin promoter (RIP). These mice will be of use in studying beta cell phenotypes resulting from the knockdown of target genes, using non- invasive bioimaging. We believe that the generation of these reporter mouse lines for diabetes studies will prove valuable in future investigations. Furthermore, the demonstration that the loss of IL-17A does not alter susceptibility to type 1 diabetes should help clarify the controversial involvement of Th17 cells in this disease.}, subject = {Diabetes mellitus}, language = {en} } @phdthesis{Sauer2011, author = {Sauer, Florian}, title = {Structural studies on the association of filamentous proteins in the human M-Bands}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-72410}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Cross-striated muscles enable higher animals to perform directed movements and to create mechanical force. The cells of heart and skeletal muscles consist of myofibrils, serial arrays of the smallest contractile subunits, the sarcomeres. Main components of the sarcomeres are the thin and thick filaments, large protein assemblies consisting of mainly actin (thin filaments) and myosin (thick filaments), whose energy-dependent interaction is responsible for the contraction of sarcomeres and so of the whole muscle. The thin filaments are anchored in the sarcomere bordering Z-discs, while the thick filaments are anchored in the M-bands, traverse structures in the sarcomere center. Electron-microscopic studies revealed that the M-bands consist of regular, lattice-like structures that appear to cross-link the thick filaments. A number of proteins could be identified by immune-fluorescence and biochemical binding studies to be present and interact with each other in the M-bands. These data have been integrated into preliminary models of the M-bands. Detailed knowledge of how these proteins interact with each other in the center of the sarcomeres is, however, largely missing. The current study focuses on the structural characterization of the interactions between the titin, myomesin-1, obscurin and obscurin-like 1 (OBSL1), modular filamentous proteins interacting with each other in the M-bands. The high-resolution crystal structure of the titin M10 - OBSL1 Ig1 complex was solved. The structure and additional biophysical data show that titin and OBSL1 as well as titin and obscurin form stable binary complexes through the formation of a small intermolecular ß-sheet. In contrast to previously characterized intermolecular assemblies of sarcomeric proteins, this sheet is formed between parallel non- homologous ß-strands of the interaction partners. The investigation of disease-related variants of the M10 domain by biophysical methods did not allow to draw unambiguous conclusions on a direct connection between impaired OBSL1/obscurin binding and disease development. Two out of four known M10 variants have effects on the correct domain folding and so interfere with the ability to bind obscurin/OBSL1. The two other known variants displayed however only minor effects on fold and binding affinities. It should therefore be further elucidated whether a direct connection between impaired complex formation and disease development exists. -I- Abstract A direct interaction between titin and myomesin-1 could not be confirmed in vitro. Possible explanations for the different results are discussed. While the consequences of the inability of both proteins to interact are unclear, the further characterization of the putative interacting parts of titin and myomesin-1 led to the discovery of two new potential sites of self-assembly on M-band titin and myomesin-1. The crystal structure of titin M4 showed that this domain can form dimeric assemblies through the formation of a disulfide bridge and an intermolecular metal binding site between residues that are unique to this domain. On myomesin-1, in addition to the described C-terminal interaction site, a potential second site of self-assembly was found in its central Fn3-domain segment. The interacting site was mapped to the predicted Fn3 domain My5. The crystal structure of the domain in its dimeric form showed that the interaction is mediated by a mechanism that has previously not been observed in sarcomeric proteins. Two My5 interact with each other by the mutual exchange of an N-terminal ß-strand which complements the Fn3 fold on the binding partner. This type of interaction can be interpreted as misfolding. However, the position of the interacting domain and its mode of interaction allowed the postulation of a model of how myomesin-1 could be integrated in the M-bands. This model is in good agreement with the electron-microscopic appearance of the M-bands.}, subject = {Muskelkontraktion}, language = {en} } @phdthesis{Tian2011, author = {Tian, Rui}, title = {Structural and functional organization of synaptic proteins in Drosophila melanogaster}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57399}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Structural and functional modifications of synaptic connections ("synaptic plasticity") are believed to mediate learning and memory processes. Thus, molecular mechanisms of how synapses assemble in both structural and functional terms are relevant for our understanding of neuronal development as well as the processes of learning and memory. Synapses form by an asymmetric association of highly specialized membrane domains: at the presynaptic active zone transmitter filled vesicles fuse, while transmitter receptors at the opposite postsynaptic density sense this signal. By genetic analysis, matrix proteins of active zones from various families have been shown to be important for fast vesicle fusion, and were suggested to contribute to synapse stability and assembly. The Sigrist lab in collaboration with the Buchner lab previously had shown that the large scaffold protein Bruchpilot (Brp) is essential for both the structural and functional integrity of active zones and for synaptic plasticity in Drosophila melanogaster. The work described in this thesis investigated several candidate proteins which appear to be involved in preand postsynaptic function, as summarized in the following: (1) DREP-2 (DEF45 related protein-2) had been found by co-immunoprecipitations with anti-Brp antibodies by Dr. Manuela Schmidt (unpublished data). Mutants and antibodies for the further study of DREP- 2 were generated in this thesis. Yeast two hybrid results suggest that DREP-2 might interact with dynein light chain 2, while in vivo imaging indicates that DREP-2 might be involved in bidirectional axonal transport. (2) Coimmunoprecipitation and pull down experiments suggested that the ARFGAP [ADP-ribosylation factor (ARF)-directed GTPase activating protein (GAP)] protein GIT (G-protein coupled receptor kinase interacting protein) could interact with the endocytosis associated molecule Stoned B (StnB). Mutants in the dgit gene showed an accumulation of large size vesicles, membrane intermediates and decreased vesicle density at the 3rd instar larval neuromuscular junction (NMJ) by electron microscopy (EM). The phenotypes accumulation of large size vesicles and membrane intermediates could be rescued partially by expression of Drosophila GIT (DGIT) or human GIT in dgit mutant background. Furthermore, by immunofluorescence the dgit mutant shows specifically decreased levels of StnB, which could be restored partially by the expression of DGIT. These results strongly support the suggestion that DGIT interacts with StnB, which is involved in the regulation of vesicle size, endocytosis or recycling of synaptic vesicles (SVs). Furthermore, the dgit mutants also showed signs of a mislocalization of the presynaptic protein Brp relative to the postsynaptic protein GluRIID, which could be rescued by expression of DGIT or human GIT in the dgit mutant background, but not by StnB. These results suggest that GIT on one hand executes roles in the regulation of synaptic vesicle endocytosis, but potentially also has structural roles for synapse assembly (3) Djm-1 is a candidate locus to mediate mental retardation in human patients when it is mutated. As a first step towards an understanding of the mechanistic role of DJM-1, Drosophila genetics were used to address DJM-1 function. So far, however, the djm-1 mutant generated in this thesis did not show a nervous system phenotype.}, subject = {Taufliege}, language = {en} } @phdthesis{Wolski2011, author = {Wolski, Stefanie Carola}, title = {Structural and functional characterization of nucleotide excision repair proteins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-67183}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {XPD is a 5'-3' helicase of the superfamily 2. As part of the transcription factor IIH it functions in transcription initiation and nucleotide excision repair. This work focus on the role of XPD in nucleotide excision repair. NER is a DNA repair pathway unique for its broad substrate range. In placental mammals NER is the only repair mechanism able to remove lesions induced by UV-light. NER can be divided into four different steps that are conserved between pro- and eukaryotes. Step 1 consists of the initial damage recognition, during step 2 the putative damage is verified, in step 3 the verified damage is excised and in the 4th and final step the resulting gap in the DNA is refilled. XPD was shown to be involved in the damage verification step. It was possible to solve the first apo XPD structure by a MAD approach using only the endogenous iron from the iron sulfur cluster. Based on the apo XPD structure several questions arise: where is DNA bound? Where is DNA separated? How is damage verification achieved? What is the role of the FeS cluster? These questions were addressed in this work. Hypothesis driven structure based functional mutagenesis was employed and combined with detailed biochemical characterization of the variants. The variants were analyzed by thermal unfolding studies to exclude the possibility that the overall stability could be affected by the point mutation. DNA binding assays, ATPase assays and helicase assays were performed to delineate amino acid residues important for DNA binding, helicase activity and damage recognition. A structure of XPD containing a four base pair DNA fragment was solved by molecular replacement. This structure displays the polarity of the translocated strand with respect to the helicase framework. Moreover the properties of the FeS cluster were studied by electron paramagnetic resonance to get insights into the role of the FeS cluster. Furthermore XPD from Ferroplasma acidarmanus was investigated since it was shown that it is stalled at CPD containing lesions. The data provide the first detailed insight into the translocation mechanism of a SF2B helicase and reveal how polarity is achieved. This provides a basis for further anlayses understanding the combined action of the helicase and the 4Fe4S cluster to accomplish damage verification within the NER cascade.}, subject = {DNS-Reparatur}, language = {en} } @article{FassnachtJohanssenAllolio2011, author = {Fassnacht, Martin and Johanssen, Sarah and Allolio, Bruno}, title = {Statements Cannot Be Substantiated : In Reply}, series = {Deutsches {\"A}rzteblatt International}, volume = {108}, journal = {Deutsches {\"A}rzteblatt International}, number = {19}, doi = {10.3238/arztebl.2011.0339b}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142597}, pages = {339-340}, year = {2011}, abstract = {No abstract available.}, language = {en} } @phdthesis{Frey2011, author = {Frey, Alexander}, title = {Spin-Dependent Tunneling and Heterovalent Heterointerface Effects in Diluted Magnetic II-VI Semiconductor Heterostructures}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-78133}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {The contribution of the present thesis consists of three parts. They are centered around investigating certain semiconductor heterointerfaces relevant to spin injection, exploring novel, diluted magnetic single barrier tunneling structures, and further developing diluted magnetic II-VI resonant tunneling diodes.}, subject = {Zwei-Sechs-Halbleiter}, language = {en} } @article{HeisigFrentzenBergmannetal.2011, author = {Heisig, Martin and Frentzen, Alexa and Bergmann, Birgit and Gentschev, Katharina Ivaylo and Hotz, Christian and Schoen, Christoph and Stritzker, Jochen and Fensterle, Joachim and Rapp, Ulf R. and Goebel, Werner}, title = {Specific antibody-receptor interactions trigger InlAB-independent uptake of Listeria monocytogenes into tumor cell lines}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68705}, year = {2011}, abstract = {Background: Specific cell targeting is an important, yet unsolved problem in bacteria-based therapeutic applications, like tumor or gene therapy. Here, we describe the construction of a novel, internalin A and B (InlAB)-deficient Listeria monocytogenes strain (Lm-spa+), which expresses protein A of Staphylococcus aureus (SPA) and anchors SPA in the correct orientation on the bacterial cell surface. Results: This listerial strain efficiently binds antibodies allowing specific interaction of the bacterium with the target recognized by the antibody. Binding of Trastuzumab (Herceptin®) or Cetuximab (Erbitux®) to Lm-spa+, two clinically approved monoclonal antibodies directed against HER2/neu and EGFR/HER1, respectively, triggers InlABindependent internalization into non-phagocytic cancer cell lines overexpressing the respective receptors. Internalization, subsequent escape into the host cell cytosol and intracellular replication of these bacteria are as efficient as of the corresponding InlAB-positive, SPA-negative parental strain. This specific antibody/receptormediated internalization of Lm-spa+ is shown in the murine 4T1 tumor cell line, the isogenic 4T1-HER2 cell line as well as the human cancer cell lines SK-BR-3 and SK-OV-3. Importantly, this targeting approach is applicable in a xenograft mouse tumor model after crosslinking the antibody to SPA on the listerial cell surface. Conclusions: Binding of receptor-specific antibodies to SPA-expressing L. monocytogenes may represent a promising approach to target L. monocytogenes to host cells expressing specific receptors triggering internalization.}, subject = {Listeria monocytogenes}, language = {en} }