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991.
Armin Birner Stephan Seiler Nina Lackner Susanne A. Bengesser Robert Queissner Frederike T. Fellendorf Martina Platzer Stefan Ropele Christian Enzinger Petra Schwingenschuh Harald Mangge Lukas Pirpamer Hannes Deutschmann Roger S. McIntyre Hans-Peter Kapfhammer Bernd Reininghaus Eva Z. Reininghaus 《PloS one》2015,10(8)
Background
Cerebral white matter lesions (WML) have been found in normal aging, vascular disease and several neuropsychiatric conditions. Correlations of WML with clinical parameters in BD have been described, but not with the number of affective episodes, illness duration, age of onset and Body Mass Index in a well characterized group of euthymic bipolar adults. Herein, we aimed to evaluate the associations between bipolar course of illness parameters and WML measured with volumetric analysis.Methods
In a cross-sectional study 100 euthymic individuals with BD as well as 54 healthy controls (HC) were enrolled to undergo brain magnetic resonance imaging using 3T including a FLAIR sequence for volumetric assessment of WML-load using FSL-software. Additionally, clinical characteristics and psychometric measures including Structured Clinical Interview according to DSM-IV, Hamilton-Depression, Young Mania Rating Scale and Beck’s Depression Inventory were evaluated.Results
Individuals with BD had significantly more (F = 3.968, p < .05) WML (Mdn = 3710mm3; IQR = 2961mm3) than HC (Mdn = 2185mm3; IQR = 1665mm3). BD men (Mdn = 4095mm3; IQR = 3295mm3) and BD women (Mdn = 3032mm3; IQR = 2816mm3) did not significantly differ as to the WML-load or the number and type of risk factors for WML. However, in men only, the number of manic/hypomanic episodes (r = 0.72; p < .001) as well as depressive episodes (r = 0.51; p < .001) correlated positively with WML-load.Conclusions
WML-load strongly correlated with the number of manic episodes in male BD patients, suggesting that men might be more vulnerable to mania in the context of cerebral white matter changes. 相似文献992.
Kim Cuddington Z. Tasker Hull Warren J. S. Currie Marten A. Koops 《Theoretical Ecology》2015,8(3):333-347
Mate-finding difficulties in small populations are often postulated to create strong demographic Allee effects that increase the probability of extinction of native species or, similarly, decrease the probability that non-native species will successfully invade. Many species make use of a restricted number of mating locations, detectable from long-distance, that are not selected for habitat reasons (e.g., hilltopping in butterflies). This ‘landmarking’ strategy may specifically address the problem of overcoming mate-finding difficulties. Using a variant of the birthday problem, we demonstrate that populations which locate a restricted number of mate-finding sites using landmark features may have high probability of successful mating even at very low population densities. Therefore, a strong Allee threshold, if it exists, may be very small, and non-native species that make use of this strategy may have a very good chance of population establishment at low density. 相似文献
993.
994.
Rhodoferax-related pufM gene cluster dominates the aerobic anoxygenic phototrophic communities in German freshwater lakes 总被引:1,自引:0,他引:1
The presence of aerobic anoxygenic phototrophs (AAPs) has been repeatedly reported from various marine environments, but their distribution in freshwater lakes was neglected until recently. We investigated the phylogenetic composition of AAP communities in 10 lakes in Northeastern Germany with different trophic status including oligotrophic Lake Stechlin and humic matter rich Lake Grosse Fuchskuhle. The AAP community was composed by members of Alpha- and Betaproteobacteria, but their contribution varied largely among the studied lakes. Our results show that AAP community composition in the studied lakes was affected mostly by pH and humic matter content. While alkaline lakes were mostly composed of Betaproteobacteria, the acidic and humic matter rich south-west (SW) basin of Lake Grosse Fuchskule was dominated (87%) by Alphaproteobacteria. The most frequent group within Betaproteobacteria was a cluster of pufM genes which was phylogenetically related to Rhodoferax representing 38.5% of all retrieved sequences. Alphaproteobacteria-related sequences had a broader phylogenetic diversity including six different taxa dominated by Sphingomonas- and Rhodobacter-like bacteria in lakes with alkaline to neutral pH. In the acidic and humic matter-rich SW basin of Lake Grosse Fuchskuhle, however, Methylobacterium-related sequences dominated the AAP community. We suggest that the variable AAP community structure might reflect the potential of these bacteria to cope with the contrasting conditions in freshwater environments. 相似文献
995.
Vödisch M Scherlach K Winkler R Hertweck C Braun HP Roth M Haas H Werner ER Brakhage AA Kniemeyer O 《Journal of proteome research》2011,10(5):2508-2524
996.
Field D Amaral-Zettler L Cochrane G Cole JR Dawyndt P Garrity GM Gilbert J Glöckner FO Hirschman L Karsch-Mizrachi I Klenk HP Knight R Kottmann R Kyrpides N Meyer F San Gil I Sansone SA Schriml LM Sterk P Tatusova T Ussery DW White O Wooley J 《PLoS biology》2011,9(6):e1001088
A vast and rich body of information has grown up as a result of the world's enthusiasm for 'omics technologies. Finding ways to describe and make available this information that maximise its usefulness has become a major effort across the 'omics world. At the heart of this effort is the Genomic Standards Consortium (GSC), an open-membership organization that drives community-based standardization activities, Here we provide a short history of the GSC, provide an overview of its range of current activities, and make a call for the scientific community to join forces to improve the quality and quantity of contextual information about our public collections of genomes, metagenomes, and marker gene sequences. 相似文献
997.
Domschke C Schuetz F Ge Y Rom J Zorn M Sinn HP Marmé F Schott S Heil J Scharf A Sohn C Schneeweiss A Beckhove P 《Cancer immunology, immunotherapy : CII》2011,60(3):401-411
A wide variety of cancer types has been associated with paraneoplastic autoimmune disorders and with the induction of autoimmunity against several autoantigens, among them self-antigens that are also expressed by tumor cells. This raises the question of autoimmune disorders as a result of immune reactions to the tumor. To date, however, requirements for the generation of autoimmune reactions in cancer patients remain largely unclear. In this study, we characterized conditions in altogether 131 patients, which determine autoimmune responses in primary breast cancer patients. We used ex vivo IFN-γ EliSpot assays against autologous tumor or skin lysates to evaluate tumor- and auto-reactive T-cells (TCs) in the bone marrow (BM) as well as ELISA, ECLIA, and turbidimetric immunoassays for the detection of auto-reactive antibodies in the peripheral blood and compared results to intratumoral cytokine concentrations and pathobiological features of the primary tumor tissue. We here demonstrate a significant correlation between anti-tumor BMTC responses and cellular autoimmune reactivity in primary breast cancer patients (P?=?0.002). Humoral autoimmune reactions, however, were negatively correlated with anti-tumor TC immunity (P?=?0.039). We observed auto-reactive BMTCs especially in patients with well-differentiated, hormone receptor-positive carcinomas (P?=?0.009). Furthermore, elevated concentrations of intratumoral IFN-α significantly correlated with the induction of cellular autoimmune reactivity (P?=?0.0002), while humoral autoimmune reactions correlated with increased levels of intratumoral IL-12 (P?=?0.04). Altogether, these data indicate a significant role of the tumor microenvironment and particularly that of IFN-α and IL-12 in the induction of systemic autoimmune responses and imply that the primary tumor tissue represents an integral site of autoimmune regulation in cancer patients. 相似文献
998.
999.
Vahed SZ Forouhandeh H Hassanzadeh S Klenk HP Hejazi MA Hejazi MS 《Mikrobiologiia》2011,80(6):826-833
Urmia Lake is one of the most permanent hypersaline lakes in the world which is threatened by hypersalinity and serious dryness. In spite of its importance no paper has been published regarding bacterial community of this lake. Accordingly, the present study aimed to investigate the halophilic bacteria in the aforementioned lake. In so doing, thirty seven strains were isolated on six different culture media. The isolated strains were characterized using phenotypic and genotypic methods. Growth of the strains occurred at 2535 degrees C, pH 6-9 and 7 to 20% (w/v) NaCl indicating that most of the isolates were moderately halophiles. Catalase, oxidase and urease activities were found to be positive for the majority of the isolates. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolated bacteria belonged to two major taxa: Gammaproteobacteria (92%, including Salicola [46%], Pseudomonas [13.5%], Marinobacter [ 11%], Idiomarina [11%], and Halomonas [8%]) and Firmicutes (8%, including Bacillus [5%] and Halobacillus [3%]). In addition, a novel bacterium whose 16S rRNA gene sequence showed almost 98% sequence identity with the taxonomically troubled DSM 3050T, Halovibrio denitrificans HGD 3T and Halospina denitrificans HGD 1-3T, each, was isolated. 16S rRNA gene similarity levels along with phenotypic characteristics suggest that some of the isolated strains could be regarded as potential type strain for novel species, on which further studies are recommended. 相似文献
1000.
A classical approach, protein separation by two-dimensional blue native/sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was combined with tandem mass spectrometry and up-to-date computer technology to characterize the mitochondrial "protein complex proteome" of Arabidopsis (Arabidopsis thaliana) in so far unrivaled depth. We further developed the novel GelMap software package to annotate and evaluate two-dimensional blue native/sodium dodecyl sulfate gels. The software allows (1) annotation of proteins according to functional and structural correlations (e.g. subunits of a distinct protein complex), (2) assignment of comprehensive protein identification lists to individual gel spots, and thereby (3) selective display of protein complexes of low abundance. In total, 471 distinct proteins were identified by mass spectrometry, several of which form part of at least 35 different mitochondrial protein complexes. To our knowledge, numerous protein complexes were described for the first time (e.g. complexes including pentatricopeptide repeat proteins involved in nucleic acid metabolism). Discovery of further protein complexes within our data set is open to everybody via the public GelMap portal at www.gelmap.de/arabidopsis_mito. 相似文献