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991.
Galectin-1, an endogenous mammalian lectin, has been implicated in a variety of CNS disorders. However, its role in cerebral ischemia is still elusive. In the present study, we investigated the effect of recombinant galectin-1 on production of astrocytic brain-derived neurotrophic factor (BDNF) and functional recovery following ischemia. Endogenous galectin-1 was found to be markedly upregulated, paralleled with increased astrocytic BDNF production under ischemic conditions both in vitro and in vivo. Administration of galectin-1significantly enhanced the expression and secretion of astrocytic BDNF in dose dependent manner. Moreover, rats subjected to photochemical cerebral ischemia showed reduced neuronal apoptosis in ischemic boundary zone and improved functional recovery after brain infusion of galectin-1 (1 μg/days, 7 days). These results suggest that induction of BDNF in astrocytes by galectin-1 may be a promising intervention to attenuate brain damage after stroke.  相似文献   
992.
骨骼的内分泌功能   总被引:1,自引:0,他引:1  
既往认为骨骼是支持机体基本结构和参与运动及钙磷代谢的主要器官。近年发现组成骨骼的成骨细胞和破骨细胞能合成和分泌多种骨调节蛋白、生长因子、脂肪因子、炎症因子和心血管活性肽等多种生物活性物质,以旁/自分泌方式调节骨骼系统功能,并能通过血液循环远距分泌的方式,调节机体能量代谢、炎症反应和内分泌稳态等。  相似文献   
993.
Clusterin (CST) is a stress-responding protein with multiple biological functions, including the inhibition of apoptosis and inflammation and transport of lipids. It may also participate in cell traffic and migration. In the process of post-infarct cardiac tissue repair, stem cells migrate into the damaged myocardium under the influence of chemoattractive substances such as stromal cell-derived factor (SDF). This study aimed at testing whether CST enhances expression of stem cell homing receptor and migration of cardiac progenitor cells (CPCs). CPCs isolated from fetal canine hearts transduced by CST cDNA expressed high levels of CXCR4, a receptor for SDF-1. The transfected cells also showed an increased migratory response to SDF-1 stimulation. The SDF-1-mediated migration of the CST-expressing CPCs was attenuated by PI3 kinase inhibitor LY294002 but not by mitogen-activated protein/ERK kinase inhibitor PD98059. Analysis of cell cycle by flow cytometry revealed no significant difference in cell cycle between the transduced and control CPCs. Thus, CST expression may increase CPCs migration via increasing CXCR4 expression and SDF-1/chemokine receptor signaling in a PI3/Akt-dependent manner.  相似文献   
994.
Detailed phytochemical investigation from the leaves of Erythrophleum fordii resulted in the isolation of 13 compounds, including three cassaine diterpenoid–diterpenoid amide dimers (1, 3 and 5), and seven cassaine diterpenoid amides (6 and 813), together with three previously reported ones, erythrophlesins D (2), C (4) and 3β-hydroxynorerythrosuamide (7). Compounds 1, 3 and 5 are further additions to the small group of cassaine diterpenoid dimers represented by erythrophlesins A–D. Their structures were determined by analysis of extensive one- and two-dimensional NMR experiments and ESIMS methods. Cytotoxic activities of the isolated compounds were tested against HCT-8, Bel-7402, BGC-823, A549 and A2780 human cancer cell lines in the MTT test. Results showed that compounds 1 and 35 exhibited significantly selective cytotoxic activities (IC50 < 10 μM) against these cells, respectively.  相似文献   
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The eukaryotic genome contains varying numbers of non-coding RNA(ncRNA) genes.Computational RNomics takes a multidisciplinary approach,like information science,to resolve the structure and function of ncRNAs.Here,we review the main issues in Computational RNomics of data storage and management,ncRNA gene identification and characterization,ncRNA target identification and functional prediction,and we summarize the main methods and current content of computational RNomics.  相似文献   
998.
Germain H  Qu N  Cheng YT  Lee E  Huang Y  Dong OX  Gannon P  Huang S  Ding P  Li Y  Sack F  Zhang Y  Li X 《PLoS genetics》2010,6(12):e1001250
Nucleocytoplasmic trafficking is emerging as an important aspect of plant immunity. The three related pathways affecting plant immunity include Nuclear Localization Signal (NLS)-mediated nuclear protein import, Nuclear Export Signal (NES)-dependent nuclear protein export, and mRNA export relying on MOS3, a nucleoporin belonging to the Nup107-160 complex. Here we report the characterization, identification, and detailed analysis of Arabidopsis modifier of snc1, 11 (mos11). Mutations in MOS11 can partially suppress the dwarfism and enhanced disease resistance phenotypes of snc1, which carries a gain-of-function mutation in a TIR-NB-LRR type Resistance gene. MOS11 encodes a conserved eukaryotic protein with homology to the human RNA binding protein CIP29. Further functional analysis shows that MOS11 localizes to the nucleus and that the mos11 mutants accumulate more poly(A) mRNAs in the nucleus, likely resulting from reduced mRNA export activity. Epistasis analysis between mos3-1 and mos11-1 revealed that MOS11 probably functions in the same mRNA export pathway as MOS3, in a partially overlapping fashion, before the mRNA molecules pass through the nuclear pores. Taken together, MOS11 is identified as a new protein contributing to the transfer of mature mRNA from the nucleus to the cytosol.  相似文献   
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