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141.
142.
Ying Lu Qiao Zhou Yongbing Shi Jian Liu Fang Zhong Xu Hao Cong Li Nan Chen Weiming Wang 《PloS one》2013,8(11)
Rosiglitazone (RGL), a synthetic agonist for peroxisome proliferator activated receptor γ (PPARγ), exhibits a potent anti-inflammatory activity by attenuating local infiltration of neutrophils and monocytes in the renal interstitium. To evaluate the mechanisms that account for inhibiting inflammatory cells infiltration, we investigated the effect of RGL on chemokines secretion and nuclear factor-kappa B (NF-κB) activation in human renal proximal tubular cells (PTCs). We demonstrated that RGL significantly inhibited lipopolysaccharide (LPS)-induced interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) production in a dose-dependent manner, without appreciable cytotoxicity. Chromatin immunoprecipitation (ChIP) assays clearly revealed that, RGL inhibited p65 binding to IL-8/MCP-1 gene promoters in LPS-stimulated PTCs. Interestingly, further experiments showed RGL reversed LPS-induced nuclear receptor corepressor (NCoR) degradation. In addition, knockdown of protein inhibitor of activated STAT1 (PIAS1), an indispensable small ubiquitin-like modifier (SUMO) ligase, abrogated the effects of RGL on antagonizing LPS-induced IL-8/MCP-1 overexpression and NCoR degradation. These findings suggest that, RGL activates PPARγ SUMOylation, inhibiting NCoR degradation and NF-κB activation in LPS-stimulated PTCs, which in turn decrease chemokines expression. The results unveil a new mechanism triggered by RGL for prevention of tubular inflammatory injury. 相似文献
143.
Extracellular vesicles from early stage Plasmodium falciparum‐infected red blood cells contain PfEMP1 and induce transcriptional changes in human monocytes 下载免费PDF全文
144.
Fuyuan Li Ning Ma Ruiqi Zhao Guodong Wu Yanfen Zhang Yu Qiao Dong Han Ya Xu Ying Xiang Bingzhu Yan Jianfeng Jin Guixiang Lv Lei Wang Changqing Xu Xu Gao Shanshun Luo 《Journal of cellular and molecular medicine》2014,18(6):966-974
The transition from liver fibrosis to hepatocellular carcinoma (HCC) has been suggested to be a continuous and developmental pathological process. MicroRNAs (miRNAs) are recently discovered molecules that regulate the expression of genes involved in liver disease. Many reports demonstrate that miR‐483‐5p and miR‐483‐3p, which originate from miR‐483, are up‐regulated in HCC, and their oncogenic targets have been identified. However, recent studies have suggested that miR‐483‐5p/3p is partially down‐regulated in HCC samples and is down‐regulated in rat liver fibrosis. Therefore, the aberrant expression and function of miR‐483 in liver fibrosis remains elusive. In this study, we demonstrate that overexpression of miR‐483 in vivo inhibits mouse liver fibrosis induced by CCl4. We demonstrate that miR‐483‐5p/3p acts together to target two pro‐fibrosis factors, platelet‐derived growth factor‐β and tissue inhibitor of metalloproteinase 2, which suppress the activation of hepatic stellate cells (HSC) LX‐2. Our work identifies the pathway that regulates liver fibrosis by inhibiting the activation of HSCs. 相似文献
145.
Aphids (Hemiptera: Aphididae) are a group of phloemfeeding insects numbering more than 5 000 extant species(Favret, 2014a). Most species have complex life cycles that include both asexual (viviparous parthenogenesis)and sexual reproduction. They display a high degree of intraspecific polyphenism with multiple phenotypes froman identical genotype, and they have specialized associations with their host plants (Blackman & Eastop, 2000).Some aphid species are gall-makers and even have evolved sociality with division of labor (Aoki, 1977; Stern &Foster, 1996). Many aphid species are agricultural and forestry pests. They incur damage to plants and carryvector plant viruses (Blackman & Eastop, 2000). Due to their fascinating biological character and economic importance, aphids have long been popular animals for research in basic and applied biology, and are becominguseful research models for studying important questions in ecology and evolution, especially in the genomic era(Brisson & Stem, 2006; Huang & Qiao, 2006; Srinivasan & Brisson, 2012). 相似文献
146.
Feng Li Biyun Chen Kun Xu Jinfeng Wu Weilin Song Ian Bancroft Andrea L. Harper Martin Trick Shengyi Liu Guizhen Gao Nian Wang Guixin Yan Jiangwei Qiao Jun Li Hao Li Xin Xiao Tianyao Zhang Xiaoming Wu 《DNA research》2014,21(4):355-367
Association mapping can quickly and efficiently dissect complex agronomic traits. Rapeseed is one of the most economically important polyploid oil crops, although its genome sequence is not yet published. In this study, a recently developed 60K Brassica Infinium® SNP array was used to analyse an association panel with 472 accessions. The single-nucleotide polymorphisms (SNPs) of the array were in silico mapped using ‘pseudomolecules’ representative of the genome of rapeseed to establish their hypothetical order and to perform association mapping of seed weight and seed quality. As a result, two significant associations on A8 and C3 of Brassica napus were detected for erucic acid content, and the peak SNPs were found to be only 233 and 128 kb away from the key genes BnaA.FAE1 and BnaC.FAE1. BnaA.FAE1 was also identified to be significantly associated with the oil content. Orthologues of Arabidopsis thaliana HAG1 were identified close to four clusters of SNPs associated with glucosinolate content on A9, C2, C7 and C9. For seed weight, we detected two association signals on A7 and A9, which were consistent with previous studies of quantitative trait loci mapping. The results indicate that our association mapping approach is suitable for fine mapping of the complex traits in rapeseed. 相似文献
147.
Wang Q Shen B Zheng P Feng H Chen L Zhang J Zhang C Zhang G Teng J Chen J 《PloS one》2010,5(10):e13252
Background
Coat protein complex I (COPI) vesicles, coated by seven coatomer subunits, are mainly responsible for Golgi-to-ER transport. Silkworm posterior silkgland (PSG), a highly differentiated secretory tissue, secretes fibroin for silk production, but many physiological processes in the PSG cells await further investigation.Methodology/Principal Findings
Here, to investigate the role of silkworm COPI, we cloned six silkworm COPI subunits (α,β,β′, δ, ε, and ζ-COP), determined their peak expression in day 2 in fifth-instar PSG, and visualized the localization of COPI, as a coat complex, with cis-Golgi. By dsRNA injection into silkworm larvae, we suppressed the expression of α-, β′- and γ-COP, and demonstrated that COPI subunits were required for PSG tube expansion. Knockdown of α-COP disrupted the integrity of Golgi apparatus and led to a narrower glandular lumen of the PSG, suggesting that silkworm COPI is essential for PSG tube expansion.Conclusions/Significance
The initial characterization reveals the essential roles of silkworm COPI in PSG. Although silkworm COPI resembles the previously characterized coatomers in other organisms, some surprising findings require further investigation. Therefore, our results suggest the silkworm as a model for studying intracellular transport, and would facilitate the establishment of silkworm PSG as an efficient bioreactor. 相似文献148.
149.
Qiao Lu Meixing Yu Chongyang Shen Xiaoping Chen Ting Feng Yongchao Yao Jinrong Li Hong Li Wenwei Tu 《PloS one》2014,9(12)
Human induced pluripotent stem cells (hiPSCs) have potential applications in cell replacement therapy and regenerative medicine. However, limited information is available regarding the immunologic features of iPSCs. In this study, expression of MHC and T cell co-stimulatory molecules in hiPSCs, and the effects on activation, proliferation and cytokine production in allogeneic human peripheral blood mononuclear cells were examined. We found that no-integrate hiPSCs had no MHC-II and T cell co-stimulatory molecules expressions but had moderate level of MHC-I and HLA-G expressions. In contrast to human skin fibroblasts (HSFs) which significantly induced allogeneic T cell activation and proliferation, hiPSCs failed to induce allogeneic CD45+ lymphocyte and CD8+ T cell activation and proliferation but could induce a low level of allogeneic CD4+ T cell proliferation. Unlike HSFs which induced allogeneic lymphocytes to produce high levels of IFN-γ, TNF-α and IL-17, hiPSCs only induced allogeneic lymphocytes to produce IL-2 and IL-10, and promote IL-10-secreting regulatory T cell (Treg) generation. Our study suggests that the integration-free hiPSCs had low or negligible immunogenicity, which may result from their induction of IL-10-secreting Treg. 相似文献
150.