TY - JOUR A1 - Bollazzi, Martin A1 - Roces, Flavio T1 - Information Needs at the Beginning of Foraging: Grass-Cutting Ants Trade Off Load Size for a Faster Return to the Nest N2 - Background: Acquisition of information about food sources is essential for animals that forage collectively like social insects. Foragers deliver two commodities to the nest, food and information, and they may favor the delivery of one at the expenses of the other. We predict that information needs should be particularly high at the beginning of foraging: the decision to return faster to the nest will motivate a grass-cutting ant worker to reduce its loading time, and so to leave the source with a partial load. Principal Findings: Field results showed that at the initial foraging phase, most grass-cutting ant foragers (Acromyrmex heyeri) returned unladen to the nest, and experienced head-on encounters with outgoing workers. Ant encounters were not simply collisions in a probabilistic sense: outgoing workers contacted in average 70% of the returning foragers at the initial foraging phase, and only 20% at the established phase. At the initial foraging phase, workers cut fragments that were shorter, narrower, lighter and tenderer than those harvested at the established one. Foragers walked at the initial phase significantly faster than expected for the observed temperatures, yet not at the established phase. Moreover, when controlling for differences in the fragment-size carried, workers still walked faster at the initial phase. Despite the higher speed, their individual transport rate of vegetable tissue was lower than that of similarly-sized workers foraging later at the same patch. Conclusions/Significance: At the initial foraging phase, workers compromised their individual transport rates of material in order to return faster to the colony. We suggest that the observed flexible cutting rules and the selection of partial loads at the beginning of foraging are driven by the need of information transfer, crucial for the establishment and maintenance of a foraging process to monopolize a discovered resource. KW - Blattschneiderameisen Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68940 ER - TY - JOUR A1 - Bittner, Stefan A1 - Bobak, Nicole A1 - Feuchtenberger, Martin A1 - Herrmann, Alexander M A1 - Göbel, Kerstin A1 - Kinne, Raimund W A1 - Hansen, Anker J A1 - Budde, Thomas A1 - Kleinschnitz, Christoph A1 - Frey, Oliver A1 - Tony, Hans-Peter A1 - Wiendl, Heinz A1 - Meuth, Sven G T1 - Expression of K\(_2\)\(_P\)5.1 potassium channels on CD4\(^+\)T lymphocytes correlates with disease activity in rheumatoid arthritis patients JF - Arthritis Research & Therapy N2 - Introduction CD4+ T cells express K2P5.1 (TWIK-related acid-sensitive potassium channel 2 (TASK2); KCNK5), a member of the two-pore domain potassium channel family, which has been shown to influence T cell effector functions. Recently, it was shown that K2P5.1 is upregulated upon (autoimmune) T cell stimulation. The aim of this study was to correlate expression levels of K2P5.1 on T cells from patients with rheumatoid arthritis (RA) to disease activity in these patients. Methods Expression levels of K2P5.1 were measured by RT-PCR in the peripheral blood of 58 patients with RA and correlated with disease activity parameters (C-reactive protein levels, erythrocyte sedimentation rates, disease activity score (DAS28) scores). Twenty patients undergoing therapy change were followed-up for six months. Additionally, synovial fluid and synovial biopsies were investigated for T lymphocytes expressing K2P5.1. Results K2P5.1 expression levels in CD4+ T cells show a strong correlation to DAS28 scores in RA patients. Similar correlations were found for serological inflammatory parameters (erythrocyte sedimentation rate, C-reactive protein). In addition, K2P5.1 expression levels of synovial fluid-derived T cells are higher compared to peripheral blood T cells. Prospective data in individual patients show a parallel behaviour of K2P5.1 expression to disease activity parameters during a longitudinal follow-up for six months. Conclusions Disease activity in RA patients correlates strongly with K2P5.1 expression levels in CD4+ T lymphocytes in the peripheral blood in cross-sectional as well as in longitudinal observations. Further studies are needed to investigate the exact pathophysiological mechanisms and to evaluate the possible use of K2P5.1 as a potential biomarker for disease activity and differential diagnosis. KW - neurology Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-139334 VL - 13 IS - R21 ER - TY - JOUR A1 - Binder, Andreas A1 - May, Denisa A1 - Baron, Ralf A1 - Maier, Christoph A1 - Tölle, Thomas R. A1 - Treede, Rolf-Detlef A1 - Berthele, Achim A1 - Faltraco, Frank A1 - Flor, Herta A1 - Gierthmühlen, Janne A1 - Haenisch, Sierk A1 - Huge, Volker A1 - Magerl, Walter A1 - Maihöfner, Christian A1 - Richter, Helmut A1 - Rolke, Roman A1 - Scherens, Andrea A1 - Üçeyler, Nurcan A1 - Ufer, Mike A1 - Wasner, Gunnar A1 - Zhu, Jihong A1 - Cascorbi, Ingolf T1 - Transient Receptor Potential Channel Polymorphisms Are Associated with the Somatosensory Function in Neuropathic Pain Patients JF - PLoS ONE N2 - 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. KW - Paradoxical heat sensation KW - Neurogenic inflammation KW - Capsaicin receptor KW - TRP Channels KW - Cold KW - Mechanisms KW - Hyperalgesia KW - Sensitivity KW - Expression KW - Stimuli Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142782 VL - 6 IS - 3 ER - TY - JOUR A1 - Bilalic, Merim A1 - Kiesel, Andrea A1 - Pohl, Carsten A1 - Erb, Michael A1 - Grodd, Wolfgang T1 - It Takes Two–Skilled Recognition of Objects Engages Lateral Areas in Both Hemispheres JF - PLoS ONE N2 - Our object recognition abilities, a direct product of our experience with objects, are fine-tuned to perfection. Left temporal and lateral areas along the dorsal, action related stream, as well as left infero-temporal areas along the ventral, object related stream are engaged in object recognition. Here we show that expertise modulates the activity of dorsal areas in the recognition of man-made objects with clearly specified functions. Expert chess players were faster than chess novices in identifying chess objects and their functional relations. Experts’ advantage was domain-specific as there were no differences between groups in a control task featuring geometrical shapes. The pattern of eye movements supported the notion that experts’ extensive knowledge about domain objects and their functions enabled superior recognition even when experts were not directly fixating the objects of interest. Functional magnetic resonance imaging (fMRI) related exclusively the areas along the dorsal stream to chess specific object recognition. Besides the commonly involved left temporal and parietal lateral brain areas, we found that only in experts homologous areas on the right hemisphere were also engaged in chess specific object recognition. Based on these results, we discuss whether skilled object recognition does not only involve a more efficient version of the processes found in non-skilled recognition, but also qualitatively different cognitive processes which engage additional brain areas KW - Expert chess players KW - Anterior inferotemporal cortex KW - Deliberate practice KW - Neural basis KW - Function knowledge KW - Parietal cortex KW - Macaque monkey KW - Temporal areas KW - Memory KW - Task Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176935 VL - 6 IS - 1 ER - TY - JOUR A1 - Biju, Joseph A1 - Schwarz, Roland A1 - Linke, Burkhard A1 - Blom, Jochen A1 - Becker, Anke A1 - Claus, Heike A1 - Goesmann, Alexander A1 - Frosch, Matthias A1 - Müller, Tobias A1 - Vogel, Ulrich A1 - Schoen, Christoph T1 - Virulence Evolution of the Human Pathogen Neisseria meningitidis by Recombination in the Core and Accessory Genome JF - PLoS One N2 - 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. KW - population genetics KW - DNA recombination KW - meningococcal disease KW - recombinant proteins KW - genomic databases KW - comparative genomics KW - neisseria meningitidis KW - homologous recombination Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137960 VL - 6 IS - 4 ER - TY - JOUR A1 - Biehl, Stefanie C. A1 - Dresler, Thomas A1 - Reif, Andreas A1 - Scheuerpflug, Peter A1 - Deckert, Jürgen A1 - Herrmann, Martin J. T1 - Dopamine Transporter (DAT1) and Dopamine Receptor D4 (DRD4) Genotypes Differentially Impact on Electrophysiological Correlates of Error Processing JF - PLoS One N2 - Recent studies as well as theoretical models of error processing assign fundamental importance to the brain's dopaminergic system. Research about how the electrophysiological correlates of error processing—the error-related negativity (ERN) and the error positivity (Pe)—are influenced by variations of common dopaminergic genes, however, is still relatively scarce. In the present study, we therefore investigated whether polymorphisms in the DAT1 gene and in the DRD4 gene, respectively, lead to interindividual differences in these error processing correlates. One hundred sixty participants completed a version of the Eriksen Flanker Task while a 26-channel EEG was recorded. The task was slightly modified in order to increase error rates. During data analysis, participants were split into two groups depending on their DAT1 and their DRD4 genotypes, respectively. ERN and Pe amplitudes after correct responses and after errors as well as difference amplitudes between errors and correct responses were analyzed. We found a differential effect of DAT1 genotype on the Pe difference amplitude but not on the ERN difference amplitude, while the reverse was true for DRD4 genotype. These findings are in line with predictions from theoretical models of dopaminergic transmission in the brain. They furthermore tie results from clinical investigations of disorders impacting on the dopamine system to genetic variations known to be at-risk genotypes. KW - haplotypes KW - electroencephalography KW - basal ganglia KW - reaction time KW - dopaminergics KW - dopamine KW - ADHD KW - research errors Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137930 VL - 6 IS - 12 ER - TY - JOUR A1 - Beyrich, Claudia A1 - Löffler, Jürgen A1 - Kobsar, Anna A1 - Speer, Christian P. A1 - Kneitz, Susanne A1 - Eigenthaler, Martin T1 - Infection of Human Coronary Artery Endothelial Cells by Group B Streptococcus Contributes to Dysregulation of Apoptosis, Hemostasis, and Innate Immune Responses [Research Article] N2 - Early onset sepsis due to group B streptococcus leads to neonatal morbidity, increased mortality, and long-term neurological deficencies. Interaction between septicemic GBS and confluent monolayers of human coronary artery endothelial cells (HCAECs) was analyzed by genome wide expression profiling. In total, 124 genes were differentially expressed (89 upregulated, 35 downregulated) based on a more than 3-fold difference to control HCAEC. Regulated genes are involved in apoptosis, hemostasis, oxidative stress response, infection, and inflammation. Regulation of selected genes and proteins identified in the gene array analysis was confirmed by Real-time RT-PCR assay (granulocy te chemotactic protein 2), ELISA (urokinase, cyclooxygenase 2, granulocyte chemotactic protein 1), and western blotting (Heme oxygenase1, BCL2 interacting protein) at various time points between 4 and 24 hours. These results indicate that GBS infection might influence signalling pathways leading to impaired function of the innate immune system and hemorrhagic and inflammatory complications during GBS sepsis. KW - Medizin Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68834 ER - TY - JOUR A1 - Beyersdorf, Niklas A1 - Werner, Sandra A1 - Wolf, Nelli A1 - Herrmann, Thomas A1 - Kerkau, Thomas T1 - Characterization of a New Mouse Model for Peripheral T Cell Lymphoma in Humans JF - PLoS One N2 - Peripheral T cell lymphomas (PTCLs) are associated with a poor prognosis due to often advanced disease at the time of diagnosis and due to a lack of efficient therapeutic options. Therefore, appropriate animal models of PTCL are vital to improve clinical management of this disease. Here, we describe a monoclonal CD8\(^+\) CD4\(^−\) αβ T cell receptor Vβ2\(^+\) CD28\(^+\) T cell lymphoma line, termed T8-28. T8-28 cells were isolated from an un-manipulated adult BALB/c mouse housed under standard pathogen-free conditions. T8-28 cells induced terminal malignancy upon adoptive transfer into syngeneic BALB/c mice. Despite intracellular expression of the cytotoxic T cell differentiation marker granzyme B, T8-28 cells appeared to be defective with respect to cytotoxic activity as read-out in vitro. Among the protocols tested, only addition of interleukin 2 in vitro could partially compensate for the in vivo micro-milieu in promoting growth of the T8-28 lymphoma cells. KW - T cells KW - cytotoxic T cells KW - mouse models KW - interleukins KW - cell staining KW - lymphomas KW - fluorescence-activated cell sorting KW - lymph nodes Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137946 VL - 6 IS - 12 ER - TY - JOUR A1 - Bergmiller, Tobias A1 - Pena-Miller, Rafael A1 - Boehm, Alexander A1 - Ackermann, Martin T1 - Single-cell time-lapse analysis of depletion of the universally conserved essential protein YgjD JF - BMC Microbiology N2 - Background: The essential Escherichia coli gene ygjD belongs to a universally conserved group of genes whose function has been the focus of a number of recent studies. Here, we put ygjD under control of an inducible promoter, and used time-lapse microscopy and single cell analysis to investigate the phenotypic consequences of the depletion of YgjD protein from growing cells. Results: We show that loss of YgjD leads to a marked decrease in cell size and termination of cell division. The transition towards smaller size occurs in a controlled manner: cell elongation and cell division remain coupled, but cell size at division decreases. We also find evidence that depletion of YgjD leads to the synthesis of the intracellular signaling molecule (p) ppGpp, inducing a cellular reaction resembling the stringent response. Concomitant deletion of the relA and spoT genes - leading to a strain that is uncapable of synthesizing (p) ppGpp abrogates the decrease in cell size, but does not prevent termination of cell division upon YgjD depletion. Conclusions: Depletion of YgjD protein from growing cells leads to a decrease in cell size that is contingent on (p) ppGpp, and to a termination of cell division. The combination of single-cell time-lapse microscopy and statistical analysis can give detailed insights into the phenotypic consequences of the loss of essential genes, and can thus serve as a new tool to study the function of essential genes. KW - Transfer-RNA modification KW - Escherichia-coli K-12 KW - Gene KW - Division KW - Expression KW - Inactivation KW - Maintenance KW - Growth KW - Level KW - Ftsz Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142324 VL - 11 IS - 118 ER - TY - JOUR A1 - Belair, Cédric A1 - Baud, Jessica A1 - Chabas, Sandrine A1 - Sharma, Cynthia M A1 - Vogel, Jörg A1 - Staedel, Cathy A1 - Darfeuille, Fabien T1 - Helicobacter pylori interferes with an embryonic stem cell micro RNA cluster to block cell cycle progression JF - Silence : a Journal of RNA regulation N2 - Background MicroRNAs, post-transcriptional regulators of eukaryotic gene expression, are implicated in host defense against pathogens. Viruses and bacteria have evolved strategies that suppress microRNA functions, resulting in a sustainable infection. In this work we report that Helicobacter pylori, a human stomach-colonizing bacterium responsible for severe gastric inflammatory diseases and gastric cancers, downregulates an embryonic stem cell microRNA cluster in proliferating gastric epithelial cells to achieve cell cycle arrest. Results Using a deep sequencing approach in the AGS cell line, a widely used cell culture model to recapitulate early events of H. pylori infection of gastric mucosa, we reveal that hsa-miR-372 is the most abundant microRNA expressed in this cell line, where, together with hsa-miR-373, it promotes cell proliferation by silencing large tumor suppressor homolog 2 (LATS2) gene expression. Shortly after H. pylori infection, miR-372 and miR-373 synthesis is highly inhibited, leading to the post-transcriptional release of LATS2 expression and thus, to a cell cycle arrest at the G1/S transition. This downregulation of a specific cell-cycle-regulating microRNA is dependent on the translocation of the bacterial effector CagA into the host cells, a mechanism highly associated with the development of severe atrophic gastritis and intestinal-type gastric carcinoma. Conclusions These data constitute a novel example of host-pathogen interplay involving microRNAs, and unveil the couple LATS2/miR-372 and miR-373 as an unexpected mechanism in infection-induced cell cycle arrest in proliferating gastric cells, which may be relevant in inhibition of gastric epithelium renewal, a major host defense mechanism against bacterial infections. KW - MicroRNAs KW - cell cycle KW - Helicobacter pylori KW - gastric cancer Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-140438 VL - 2 IS - 7 ER - TY - JOUR A1 - Bartl, Jasmin A1 - Scholz, Claus-Jürgen A1 - Hinterberger, Margareta A1 - Jungwirth, Susanne A1 - Wichart, Ildiko A1 - Rainer, Michael K. A1 - Kneitz, Susanne A1 - Danielczyk, Walter A1 - Tragl, Karl H. A1 - Fischer, Peter A1 - Riederer, Peter A1 - Grünblatt, Edna T1 - Disorder-specific effects of polymorphisms at opposing ends of the Insulin Degrading Enzymegene JF - BMC Medical Genetics N2 - Background Insulin-degrading enzyme (IDE) is the ubiquitously expressed enzyme responsible for insulin and amyloid beta (Aβ) degradation. IDE gene is located on chromosome region 10q23-q25 and exhibits a well-replicated peak of linkage with Type 2 diabetes mellitus (T2DM). Several genetic association studies examined IDE gene as a susceptibility gene for Alzheimer's disease (AD), however with controversial results. Methods We examined associations of three IDE polymorphisms (IDE2, rs4646953; IDE7, rs2251101 and IDE9, rs1887922) with AD, Aβ42 plasma level and T2DM risk in the longitudinal Vienna Transdanube Aging (VITA) study cohort. Results The upstream polymorphism IDE2 was found to influence AD risk and to trigger the Aβ42 plasma level, whereas the downstream polymorphism IDE7 modified the T2DM risk; no associations were found for the intronic variant IDE9. Conclusions Based on our SNP and haplotype results, we delineate the model that IDE promoter and 3' untranslated region/downstream variation may have different effects on IDE expression, presumably a relevant endophenotype with disorder-specific effects on AD and T2DM susceptibility. KW - Insulin Degrading Enzyme Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137744 VL - 12 IS - 151 ER - TY - JOUR A1 - Baptistella Florence, Michelle Etienne A1 - Massuda, Juliana Yumi A1 - Bröcker, Eva-Bettina A1 - Metze, Konradin A1 - Cintra, Maria Leticia A1 - de Souza, Elemir Macedo T1 - Angiogenesis in the progression of cutaneous squamous cell carcinoma: an immunohistochemical study of endothelial markers JF - CLINICS N2 - OBJECTIVE: To demonstrate the role of angiogenesis in the progression of cutaneous squamous cell carcinoma. INTRODUCTION: Angiogenesis is a pivotal phenomenon in carcinogenesis. Its time course in cutaneous squamous cell carcinoma has not yet been fully established. METHODS: We studied the vascular bed in 29 solar keratoses, 30 superficially invasive squamous cell carcinomas and 30 invasive squamous cell carcinomas. The Chalkley method was used to quantify the microvascular area by comparing panendothelial (CD34) with neoangiogenesis (CD105) immunohistochemical markers. The vascular bed from non-neoplastic adjacent skin was evaluated in 8 solar keratoses, 10 superficially invasive squamous cell carcinomas and 10 invasive squamous cell carcinomas. RESULTS: The microvascular area in CD105-stained specimens significantly increased in parallel with cutaneous squamous cell carcinoma progression. However, no differences between groups were found in CD34 sections. Solar keratosis, superficially invasive squamous cell carcinoma and invasive squamous cell carcinoma samples showed significant increases in microvascular area for both CD34- and CD105-stained specimens compared with the respective adjacent skin. DISCUSSION: The angiogenic switch occurs early in the development of cutaneous squamous cell carcinoma, and the rate of neovascularization is parallel to tumor progression. In contrast to panendothelial markers, CD105 use allows a dynamic evaluation of tumor angiogenesis. CONCLUSION: This study demonstrated the dependence of skin carcinogenesis on angiogenesis. KW - Pathologic neovascularization KW - CD105 antigen KW - human KW - CD34 antigen KW - skin neoplasms KW - keratosis Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133650 VL - 66 IS - 3 ER - TY - JOUR A1 - Avota, Elita A1 - Gulbins, Erich A1 - Schneider-Schaulies, Sibylle T1 - DC-SIGN Mediated Sphingomyelinase-Activation and Ceramide Generation Is Essential for Enhancement of Viral Uptake in Dendritic Cells N2 - As pattern recognition receptor on dendritic cells (DCs), DC-SIGN binds carbohydrate structures on its pathogen ligands and essentially determines host pathogen interactions because it both skews T cell responses and enhances pathogen uptake for cis infection and/or T cell trans-infection. How these processes are initiated at the plasma membrane level is poorly understood. We now show that DC-SIGN ligation on DCs by antibodies, mannan or measles virus (MV) causes rapid activation of neutral and acid sphingomyelinases followed by accumulation of ceramides in the outer membrane leaflet. SMase activation is important in promoting DC-SIGN signaling, but also for enhancement of MV uptake into DCs. DCSIGN-dependent SMase activation induces efficient, transient recruitment of CD150, which functions both as MV uptake receptor and microbial sensor, from an intracellular Lamp-1+ storage compartment shared with acid sphingomyelinase (ASM) within a few minutes. Subsequently, CD150 is displayed at the cell surface and co-clusters with DC-SIGN. Thus, DCSIGN ligation initiates SMase-dependent formation of ceramide-enriched membrane microdomains which promote vertical segregation of CD150 from intracellular storage compartments along with ASM. Given the ability to promote receptor and signalosome co-segration into (or exclusion from) ceramide enriched microdomains which provide a favorable environment for membrane fusion, DC-SIGN-dependent SMase activation may be of general importance for modes and efficiency of pathogen uptake into DCs, and their routing to specific compartments, but also for modulating T cell responses. KW - Dendritische Zelle Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-69056 ER - TY - JOUR A1 - Avota, Elita A1 - Gassert, Evelyn A1 - Schneider-Schaulies, Sibylle T1 - Cytoskeletal Dynamics: Concepts in Measles Virus Replication and Immunomodulation N2 - In common with most viruses, measles virus (MV) relies on the integrity of the cytoskeleton of its host cells both with regard to efficient replication in these cells, but also retention of their motility which favors viral dissemination. It is, however, the surface interaction of the viral glycoprotein (gp) complex with receptors present on lymphocytes and dendritic cells (DCs), that signals effective initiation of host cell cytoskeletal dynamics. For DCs, these may act to regulate processes as diverse as viral uptake and sorting, but also the ability of these cells to successfully establish and maintain functional immune synapses (IS) with T cells. In T cells, MV signaling causes actin cytoskeletal paralysis associated with a loss of polarization, adhesion and motility, which has been linked to activation of sphingomyelinases and subsequent accumulation of membrane ceramides. MV modulation of both DC and T cell cytoskeletal dynamics may be important for the understanding of MV immunosuppression at the cellular level. KW - Virologie KW - measles virus KW - cytoskeleton KW - sphingomyelinase Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-69092 ER - TY - JOUR A1 - Ascierto, Maria Libera A1 - Worschech, Andrea A1 - Yu, Zhiya A1 - Adams, Sharon A1 - Reinboth, Jennifer A1 - Chen, Nanhai G A1 - Pos, Zoltan A1 - Roychoudhuri, Rahul A1 - Di Pasquale, Giovanni A1 - Bedognetti, Davide A1 - Uccellini, Lorenzo A1 - Rossano, Fabio A1 - Ascierto, Paolo A A1 - Stroncek, David F A1 - Restifo, Nicholas P A1 - Wang, Ena A1 - Szalay, Aladar A A1 - Marincola, Francesco M T1 - Permissivity of the NCI-60 cancer cell lines to oncolytic Vaccinia Virus GLV-1h68 JF - BMC Cancer N2 - Background: Oncolytic viral therapy represents an alternative therapeutic strategy for the treatment of cancer. We previously described GLV-1h68, a modified Vaccinia Virus with exclusive tropism for tumor cells, and we observed a cell line-specific relationship between the ability of GLV-1h68 to replicate in vitro and its ability to colonize and eliminate tumor in vivo. Methods: In the current study we surveyed the in vitro permissivity to GLV-1h68 replication of the NCI-60 panel of cell lines. Selected cell lines were also tested for permissivity to another Vaccinia Virus and a vesicular stomatitis virus (VSV) strain. In order to identify correlates of permissity to viral infection, we measured transcriptional profiles of the cell lines prior infection. Results: We observed highly heterogeneous permissivity to VACV infection amongst the cell lines. The heterogeneity of permissivity was independent of tissue with the exception of B cell derivation. Cell lines were also tested for permissivity to another Vaccinia Virus and a vesicular stomatitis virus (VSV) strain and a significant correlation was found suggesting a common permissive phenotype. While no clear transcriptional pattern could be identified as predictor of permissivity to infection, some associations were observed suggesting multifactorial basis permissivity to viral infection. Conclusions: Our findings have implications for the design of oncolytic therapies for cancer and offer insights into the nature of permissivity of tumor cells to viral infection. KW - gene-therapy KW - adenovirus KW - receptor KW - identification KW - infection KW - CD9 KW - panel Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-141503 VL - 11 IS - 451 ER - TY - JOUR A1 - Arnold, Thomas A1 - Braunschweig, Holger A1 - Gruss, Katrin T1 - cyclo-Tri-mu-oxido-tris{[(eta 5,eta 5)-1,2-bis(cyclopentadienyl)-1,1,2,2-tetramethyldisilane]zirconium(IV)}: a trimeric disila-bridged oxidozirconocene JF - Acta Crystallographica Section E: metal-organic compounds N2 - The title compound, [Zr(3)(C(14)H(20)Si(2))(3)O(3)], consists of three disila-bridged zirconocene units, which are connected via an oxide ligand, forming a nearly planar six-membered ring with a maximum displacement of 0.0191 (8) A. The compound was isolated as a by-product from a mixture of [(C(5)H(4)SiMe(2))(2)ZrCl(2)] and Li[AlH(4)] in Et(2)O. KW - Kristallographie Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134802 VL - 67 ER - TY - JOUR A1 - Arlt, Wiebke A1 - Biehl, Michael A1 - Taylor, Angela E. A1 - Hahner, Stefanie A1 - Libé, Rossella A1 - Hughes, Beverly A. A1 - Schneider, Petra A1 - Smith, David J. A1 - Stiekema, Han A1 - Krone, Nils A1 - Porfiri, Emilio A1 - Opocher, Giuseppe A1 - Bertherat, Jerôme A1 - Mantero, Franco A1 - Allolio, Bruno A1 - Terzolo, Massimo A1 - Nightingale, Peter A1 - Shackleton, Cedric H. L. A1 - Bertagna, Xavier A1 - Fassnacht, Martin A1 - Stewart, Paul M. T1 - Urine Steroid Metabolomics as a Biomarker Tool for Detecting Malignancy in Adrenal Tumors JF - The Journal of Clinical Endocrinology & Metabolism N2 - 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. KW - adrenal cortex hormones KW - urine KW - adrenal cortex neoplasms KW - mass spectrometry KW - metabolomics Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-154682 VL - 96 IS - 12 SP - 3775 EP - 3784 ER - TY - JOUR A1 - Arhondakis, Stilianos A1 - Frousios, Kimon A1 - Iliopoulos, Costas S. A1 - Pissis, Solon P. A1 - Tischler, German A1 - Kossida, Sophia T1 - Transcriptome map of mouse isochores JF - BMC Genomics N2 - 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. KW - Biased gene conversion KW - Human genome KW - GC-Content KW - Mammalian genomes KW - Base composition KW - Expresses genes KW - Higher rates KW - RNA-SEQ KW - Evolution KW - Rodents Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142773 VL - 12 IS - 511 ER - TY - JOUR A1 - Allignol, Arthur A1 - Schumacher, Martin A1 - Wanner, Christoph A1 - Drechsler, Christiane A1 - Beyersmann, Jan T1 - Understanding competing risks: a simulation point of view JF - BMC Medical Research Methodology N2 - 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. KW - Cumulative incidence function KW - Clinical-trials KW - Sample-sizes KW - Regression KW - Subdistribution KW - Hazards KW - Model KW - Probabilities KW - Tests Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142811 VL - 11 IS - 86 ER - TY - JOUR A1 - Albrecht, Marco A1 - Sharma, Cynthia M. A1 - Dittrich, Marcus T. A1 - Müller, Tobias A1 - Reinhardt, Richard A1 - Vogel, Jörg A1 - Rudel, Thomas T1 - The Transcriptional Landscape of Chlamydia pneumoniae N2 - 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. KW - Chlamydia pneumoniae Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-69116 ER - TY - JOUR T1 - Measurement of the inelastic proton–proton cross-section at √s=7 TeV with the ATLAS detector JF - Nature Communications N2 - The dependence of the rate of proton–proton interactions on the centre-of-mass collision energy, √s, is of fundamental importance for both hadron collider physics and particle astrophysics. The dependence cannot yet be calculated from first principles; therefore, experimental measurements are needed. Here we present the first measurement of the inelastic proton–proton interaction cross-section at a centre-of-mass energy, √s, of 7 TeV using the ATLAS detector at the Large Hadron Collider. Events are selected by requiring hits on scintillation counters mounted in the forward region of the detector. An inelastic cross-section of 60.3±2.1 mb is measured for ξ>5×10−6, where ξ is calculated from the invariant mass, MX, of hadrons selected using the largest rapidity gap in the event. For diffractive events, this corresponds to requiring at least one of the dissociation masses to be larger than 15.7 GeV. KW - Physical Sciences KW - Particle physics Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-140960 VL - 2 ER -