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ObjectiveWe investigated whether glutamate, NMDA receptors, and eukaryote elongation factor-2 kinase (eEF-2K)/eEF-2 regulate P-glycoprotein expression, and the effects of the eEF-2K inhibitor NH125 on the expression of P-glycoprotein in rat brain microvessel endothelial cells (RBMECs).MethodsCortex was obtained from newborn Wistar rat brains. After surface vessels and meninges were removed, the pellet containing microvessels was resuspended and incubated at 37°C in culture medium. Cell viability was assessed by the MTT assay. RBMECs were identified by immunohistochemistry with anti-vWF. P-glycoprotein, phospho-eEF-2, and eEF-2 expression were determined by western blot analysis. Mdr1a gene expression was analyzed by RT-PCR.ResultsMdr1a mRNA, P-glycoprotein and phospho-eEF-2 expression increased in L-glutamate stimulated RBMECs. P-glycoprotein and phospho-eEF-2 expression were down-regulated after NH125 treatment in L-glutamate stimulated RBMECs.ConclusionseEF-2K/eEF-2 should have played an important role in the regulation of P-glycoprotein expression in RBMECs. eEF-2K inhibitor NH125 could serve as an efficacious anti-multidrug resistant agent. 相似文献
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Yixin Zheng Xuejie Fu Qingbai Liu Shengqi Guan Cunchang Liu Chunmei Xiu Tingting Gong Hongting Jin Saijilafu Zunyi Zhang Di Chen Jianquan Chen 《Journal of cellular physiology》2019,234(9):14422-14431
Cre/loxP technology is an important tool for studying cell type-specific gene functions. Cre recombinase mouse lines, including Agc1-CreERT2, Col2a1-Cre; Col2a1-CreERT2, Shh-Cre, Shh-CreERT2, and Osx-Cre, have been proven to be valuable tools to elucidate the biology of long bones, yet the information for their activity in postnatal intervertebral disc (IVD) tissues was very limited. In this study, we used R26-mTmG fluorescent reporter to systematically analyze cell specificity and targeting efficiency of these six mouse lines in IVD tissues at postnatal growing and adult stages. We found that Agc1-CreERT2 is effective to direct recombination in all components of IVDs, including annulus fibrosus (AF), nucleus pulposus (NP), and cartilaginous endplate (CEP), upon tamoxifen induction at either 2 weeks or 2 months of ages. Moreover, Col2a1-Cre targets most of the cells in IVDs, except for some cells in the outer AF (OAF) and NP. In contrast, the activity of Col2a1-CreERT2 is mainly limited to the IAF of IVD tissues at either stage of tamoxifen injection. Similarly, Shh-Cre directs recombination specifically in all NP cells, whereas Shh-CreERT2 is active only in a few NP cells when tamoxifen is administered at either stage. Finally, Osx-Cre targets cells in the CEP, but not in the NP or AF of IVDs tissues at these two stages. Thus, our data demonstrated that all these Cre lines can direct recombination in IVD tissues at postnatal stages with different cell type specificity and/or targeting efficiency, and can, therefore, serve as valuable tools to dissect cell type-specific gene functions in IVD development and homeostasis. 相似文献
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The development of habitat suitability models requires a large amount of data which are rarely available. In this case, researchers need to get information on the ecological features of the studied species, based on the opinion of experts or on the literature, to construct a qualitative model. However, such models cannot be rigorously evaluated, as in most cases absence points are not available. In this paper, we assess the habitat suitability for a vulnerable insectivorous plant, Pinguicula crystallina Sibth. et Smith subsp. hirtiflora (Ten.) Strid (Lentibulariaceae) in the Campania region. Our aim was to develop an expert-based, presence-only model in support of possible conservation actions. Topographic and geological features of this species suggested by the literature were used in our model. Both the Boyce index and field surveys were chosen to evaluate the model's reliability. During field surveys, 31 absence sites and 1 new presence site were identified, and differences between sites with regard to water chemistry and quality were investigated, water being an element in the species habitat. Factors that affect reliability of the model, such as the lack of a large amount of information on the species and the limited spatial resolution of geographical information system data, are discussed. 相似文献
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从最高人民法院的一个典型案例出发,探讨药物组合物封闭式权利要求保护范围的解读及其专利侵权判定标准,比较其他国家
的相关规定和判例,并对药物组合物封闭式权利要求的专利授权、确权审查、侵权判定以及申请文件撰写技巧提出见解,以供借鉴和参考。 相似文献
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Sonia Tarazona Pedro Furió-Tarí David Turrà Antonio Di Pietro María José Nueda Alberto Ferrer Ana Conesa 《Nucleic acids research》2015,43(21):e140
As the use of RNA-seq has popularized, there is an increasing consciousness of the importance of experimental design, bias removal, accurate quantification and control of false positives for proper data analysis. We introduce the NOISeq R-package for quality control and analysis of count data. We show how the available diagnostic tools can be used to monitor quality issues, make pre-processing decisions and improve analysis. We demonstrate that the non-parametric NOISeqBIO efficiently controls false discoveries in experiments with biological replication and outperforms state-of-the-art methods. NOISeq is a comprehensive resource that meets current needs for robust data-aware analysis of RNA-seq differential expression. 相似文献
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The classical Botts-Morales theory for the action of a modifier on the catalytic properties of an enzyme has been extended to deal with allosteric effects in serine proteases. The exact analytical solution derived for the linkage scheme at steady state provides a rigorous framework for the study of many biologically relevant systems, including enzymes activated by monovalent cations and cofactor-controlled protease-zymogen interactions in blood coagulation. When the enzyme obeys Michaelis-Menten kinetics, the exact solution of the kinetic linkage scheme simplifies considerably. Of particular importance for practical applications is a simple equation expressing the dependence of the specificity constant of the enzyme, kcat/Km, on the concentration of the modifier, from which the equilibrium binding constant for the formation of the enzyme-modifier complex can be estimated. Analysis of the allosteric changes in thrombin activity induced by thrombomodulin and Na+ in terms of this equation yields accurate determinations of the equilibrium binding constants for both effectors. 相似文献
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