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Cem Gabay Veit Krenn Carine Bosshard Alexander Christian Seemayer Carlo Chizzolini Bertrand Huard 《Arthritis research & therapy》2009,11(5):R144
Introduction
A proliferation-inducing ligand (APRIL) from the TNF family, owing to its role in the generation and survival of plasma cells (PCs), is currently targeted for rheumatoid arthritis (RA) treatment. However, little is known about APRIL expression in RA lesions, hampering our understanding of the way APRIL may modulate this autoimmune disease. 相似文献4.
The FTD‐like syndrome causing TREM2 T66M mutation impairs microglia function,brain perfusion,and glucose metabolism 下载免费PDF全文
Gernot Kleinberger Matthias Brendel Eva Mracsko Benedikt Wefers Linda Groeneweg Xianyuan Xiang Carola Focke Maximilian Deußing Marc Suárez‐Calvet Fargol Mazaheri Samira Parhizkar Nadine Pettkus Wolfgang Wurst Regina Feederle Peter Bartenstein Thomas Mueggler Thomas Arzberger Irene Knuesel Axel Rominger Christian Haass 《The EMBO journal》2017,36(13):1837-1853
Genetic variants in the triggering receptor expressed on myeloid cells 2 (TREM2) increase the risk for several neurodegenerative diseases including Alzheimer's disease and frontotemporal dementia (FTD). Homozygous TREM2 missense mutations, such as p.T66M, lead to the FTD‐like syndrome, but how they cause pathology is unknown. Using CRISPR/Cas9 genome editing, we generated a knock‐in mouse model for the disease‐associated Trem2 p.T66M mutation. Consistent with a loss‐of‐function mutation, we observe an intracellular accumulation of immature mutant Trem2 and reduced generation of soluble Trem2 similar to patients with the homozygous p.T66M mutation. Trem2 p.T66M knock‐in mice show delayed resolution of inflammation upon in vivo lipopolysaccharide stimulation and cultured macrophages display significantly reduced phagocytic activity. Immunohistochemistry together with in vivo TSPO small animal positron emission tomography (μPET) demonstrates an age‐dependent reduction in microglial activity. Surprisingly, perfusion magnetic resonance imaging and FDG‐μPET imaging reveal a significant reduction in cerebral blood flow and brain glucose metabolism. Thus, we demonstrate that a TREM2 loss‐of‐function mutation causes brain‐wide metabolic alterations pointing toward a possible function of microglia in regulating brain glucose metabolism. 相似文献
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Proteins governing cell death form the basis of many normal processes and contribute to the pathogenesis of many diseases when dysregulated. Here we report the cloning of a novel human CED-4-like gene, CLAN, and several of its alternatively spliced isoforms. These caspase-associated recruitment domain (CARD)-containing proteins are expressed at varying degrees in normal human tissues and may contribute to a number of intracellular processes including apoptosis, cytokine processing, and NF-κB activation. The CARD of the CLAN proteins binds a number of other CARD-containing proteins including caspase-1, BCL10, NOD2, and NAC. Once their physiologic functions are uncovered, CLAN proteins may prove to be valuable therapeutic targets. 相似文献
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CDPKs and 14-3-3 Proteins: Emerging Duo in Signaling 总被引:1,自引:0,他引:1
Mélanie Ormancey Patrice Thuleau Christian Mazars Valérie Cotelle 《Trends in plant science》2017,22(3):263-272
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Nuno Santos Catarina Santos Teresa Valente Christian Gortázar Virgílio Almeida Margarida Correia-Neves 《PloS one》2015,10(11)
Environmental contamination with Mycobacterium tuberculosis complex (MTC) has been considered crucial for bovine tuberculosis persistence in multi-host-pathogen systems. However, MTC contamination has been difficult to detect due to methodological issues. In an attempt to overcome this limitation we developed an improved protocol for the detection of MTC DNA. MTC DNA concentration was estimated by the Most Probable Number (MPN) method. Making use of this protocol we showed that MTC contamination is widespread in different types of environmental samples from the Iberian Peninsula, which supports indirect transmission as a contributing mechanism for the maintenance of bovine tuberculosis in this multi-host-pathogen system. The proportion of MTC DNA positive samples was higher in the bovine tuberculosis-infected than in presumed negative area (0.32 and 0.18, respectively). Detection varied with the type of environmental sample and was more frequent in sediment from dams and less frequent in water also from dams (0.22 and 0.05, respectively). The proportion of MTC-positive samples was significantly higher in spring (p<0.001), but MTC DNA concentration per sample was higher in autumn and lower in summer. The average MTC DNA concentration in positive samples was 0.82 MPN/g (CI95 0.70–0.98 MPN/g). We were further able to amplify a DNA sequence specific of Mycobacterium bovis/caprae in 4 environmental samples from the bTB-infected area. 相似文献
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Bahareh Majnon Jahromi Mehdi Gheibi Christian Kehlmaier Shahram Hesami 《Zoology in the Middle East.》2017,63(4):336-347
A checklist of 39 species of the genus Tomosvaryella Aczél (Diptera, Pipunculidae) known from the Middle East is provided. A new species, T. hamata Majnon Jahromi &; Kehlmaier sp. n. is described from southern Iran and diagnostic characters of male and female terminalia are illustrated. Tomosvaryella dentiterebra (Collin, 1949) is redescribed and male and female terminalia are illustrated for the first time. A phylogenetic maximum-likelihood analysis and uncorrected pairwise genetic distances of 18 out of 22 Iranian species of Tomosvaryella based on DNA barcodes of the mitochondrial COI gene are presented and also discussed.http://www.zoobank.org/urn:lsid:zoobank.org:pub:FF8C116D-0C92-431A-B52C-11F3711B6A62 相似文献
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Rozemarijn van der Ploeg Christian Steglich Christina Salmivalli René Veenstra 《PloS one》2015,10(10)
The association between experienced victimization and students'' psychological and social adjustment depends on the intensity of victimization. We examined how frequency and multiplicity of victimization, and the number of bullies involved, account for differences in students’ psychosocial well-being and social standing in the classroom. Multilevel analyses were conducted on the control group of an intervention study among students in grades 3–6 of Dutch elementary schools (N = 2859 students from 124 classes and 33 schools; ages 8–12; 49.6% boys). It was found that victims of frequent and multiple victimization, and victims who were victimized by several bullies, had higher levels of psychosocial adjustment problems than victims of less frequent and non-multiple victimization, and victims with only one bully. Moreover, these more severe victims turned out to be least accepted and most rejected among their classmates. The findings illustrate that it can be fruitful to use several measures of victimization so that (differences in) adjustment problems can be better understood. Moreover, the results suggest that it is important to find out who is victimized, in what ways, and by whom. Anti-bullying interventions should provide resources to do this. 相似文献
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Claudia Pogoreutz Nils Rädecker Anny Cárdenas Astrid Gärdes Christian R. Voolstra Christian Wild 《Global Change Biology》2017,23(9):3838-3848
The disruption of the coral–algae symbiosis (coral bleaching) due to rising sea surface temperatures has become an unprecedented global threat to coral reefs. Despite decades of research, our ability to manage mass bleaching events remains hampered by an incomplete mechanistic understanding of the processes involved. In this study, we induced a coral bleaching phenotype in the absence of heat and light stress by adding sugars. The sugar addition resulted in coral symbiotic breakdown accompanied by a fourfold increase of coral‐associated microbial nitrogen fixation. Concomitantly, increased N:P ratios by the coral host and algal symbionts suggest excess availability of nitrogen and a disruption of the nitrogen limitation within the coral holobiont. As nitrogen fixation is similarly stimulated in ocean warming scenarios, here we propose a refined coral bleaching model integrating the cascading effects of stimulated microbial nitrogen fixation. This model highlights the putative role of nitrogen‐fixing microbes in coral holobiont functioning and breakdown. 相似文献