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121.
Astrocytes,cells involved in neuro-immune interactions in the central nervous system 总被引:2,自引:0,他引:2
Giraudon P Malcus C Chalon A Vincent P Khuth S Bernard A Belin MF 《Journal de la Société de Biologie》2003,197(2):103-112
The astrocyte, the major glial cell in the central nervous system, may influence many aspects of inflammation and immune reactivity within the brain. We have established a model of chronically activated T lymphocytes, interacting with neural cells of diverse origin to study the complex immune regulatory system suspected to lead to neuroinflammatory diseases. We show that human astrocytes became reactive following T cell contact, secreting proinflammatory cytokines, matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinase (TIMP). The altered MMP/TIMP system was shown to be involved in deleterious effects displayed by activated T cells towards human multipotent neural precursers by controlling their sensitivity to T cell-induced Fas-mediated apoptosis. MMP/TIMP was suspected to stabilize Fas at the cell membrane. In a model of mixed rat glial cells in primary culture (astrocytes, oligodendrocytes), activated T lymphocytes induced the collapse of processes and the death of immature oligodendrocytes. These effects were associated with upregulation of Fas at the cell surface of oligodendrocytes and secretion of MMP and TIMP by astrocytes. By amplifying the expression of inflammatory molecules including the MMP/TIMP system, astrocytes appear to be a crucial relay in the deleterious molecular cascade triggered by activated T lymphocytes. Detection of altered MMP/TIMP in patients suffering from myelopathy associated with retroviral infection (HTLV-1) strongly suggests its involvement in the physiopathological process of the disease. 相似文献
122.
Transcriptional silencing of the TFPI-2 gene by promoter hypermethylation in choriocarcinoma cells 总被引:7,自引:0,他引:7
Hubé F Reverdiau P Iochmann S Rollin J Cherpi-Antar C Gruel Y 《Biological chemistry》2003,384(7):1029-1034
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Anderle P Duval M Draghici S Kuklin A Littlejohn TG Medrano JF Vilanova D Roberts MA 《BioTechniques》2003,(Z1):36-44
The DNA microarray technology has arguably caught the attention of the worldwide life science community and is now systematically supporting major discoveries in many fields of study. The majority of the initial technical challenges of conducting experiments are being resolved, only to be replaced with new informatics hurdles, including statistical analysis, data visualization, interpretation, and storage. Two systems of databases, one containing expression data and one containing annotation data are quickly becoming essential knowledge repositories of the research community. This present paper surveys several databases, which are considered "pillars" of research and important nodes in the network. This paper focuses on a generalized workflow scheme typical for microarray experiments using two examples related to cancer research. The workflow is used to reference appropriate databases and tools for each step in the process of array experimentation. Additionally, benefits and drawbacks of current array databases are addressed, and suggestions are made for their improvement. 相似文献
125.
Levadoux-Martin M Gouble A Jégou B Vallet-Erdtmann V Auriol J Mercier P Morello D 《EMBO reports》2003,4(4):394-399
A series of experiments, using cell culture models or in vitro assays, has shown that the RNA-binding protein HuR increases the half-life of some messenger RNAs that contain adenylate/uridylate-rich decay elements. However, its function in an integrated system has not yet been investigated. Here, using a mouse model, we report that misregulation of HuR, due to expression of an HuR transgene, prevents the production of fully functional gametes. This work provides the first evidence for a physiological function of HuR, and highlights its involvement in spermatogenesis. 相似文献
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Fungi isolated from soil in Timna Park (Israel) were found to belong to a new species of Exserohilum for which the name Exserohilum israeli sp. nov. is proposed. The main physiological properties of members of this species are discussed and the influence of temperature and copper concentrations on the growth and morphology of the fungus were investigated. 相似文献
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