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71.
KCNQ1 variants associate with hypertension in type 2 diabetes and affect smooth muscle contractility in vitro 下载免费PDF全文
Kuo‐Chin Huang Te‐Mao Li Xiang Liu Jin‐Hua Chen Wen‐Kuei Chien Yi‐Tzone Shiao Hsinyi Tsang Ting‐Hsu Lin Chiu‐Chu Liao Shao‐Mei Huang Ju‐Pi Li Cheng‐Wen Lin Jung‐Chun Lin Chih‐Chien Lin Chih‐Ho Lai Chi‐Fung Cheng Wen‐Miin Liang Chien‐Hui Hung Ching‐Chu Chen Ying‐Ju Lin Fuu‐Jen Tsai 《Journal of cellular physiology》2017,232(12):3309-3316
72.
Biochemical characterization of RssA-RssB, a two-component signal transduction system regulating swarming behavior in Serratia marcescens 下载免费PDF全文
Wei JR Tsai YH Soo PC Horng YT Hsieh SC Ho SW Lai HC 《Journal of bacteriology》2005,187(16):5683-5690
Our previous study had identified a pair of potential two-component signal transduction proteins, RssA-RssB, involved in the regulation of Serratia marcescens swarming. When mutated, both rssA and rssB mutants showed precocious swarming phenotypes on LB swarming agar, whereby swarming not only occurred at 37 degrees C but also initiated on a surface of higher agar concentration and more rapidly than did the parent strain at 30 degrees C. In this study, we further show that the predicted sensor kinase RssA and the response regulator RssB bear characteristics of components of the phosphorelay signaling system. In vitro phosphorylation and site-directed mutagenesis assays showed that phosphorylated RssA transfers the phosphate group to RssB and that histidine 248 and aspartate 51 are essential amino acid residues involved in the phosphotransfer reactions in RssA and RssB, respectively. Accordingly, while wild-type rssA could, the mutated rssA(H248A) in trans could not complement the precocious swarming phenotype of the rssA mutant. Although RssA-RssB regulates expressions of shlA and ygfF of S. marcescens (ygfF(Sm)), in vitro DNA-binding assays showed that the phosphorylated RssB did not bind directly to the promoter regions of these two genes but bound to its own rssB promoter. Subsequent assays located the RssB binding site within a 63-bp rssB promoter DNA region and confirmed a direct negative autoregulation of the RssA-RssB signaling pathway. These results suggest that when activated, RssA-RssB acts as a negative regulator for controlling the initiation of S. marcescens swarming. 相似文献
73.
Lai CM Yu MJ Brankov M Barnett NL Zhou X Redmond TM Narfstrom K Rakoczy PE 《Genetic vaccines and therapy》2004,2(1):3
Background
Leber's congenital amaurosis (LCA) is a severe form of retinal dystrophy. Mutations in the RPE65 gene, which is abundantly expressed in retinal pigment epithelial (RPE) cells, account for approximately 10–15% of LCA cases. In this study we used the high turnover, and rapid breeding and maturation time of the Rpe65 -/- knockout mice to assess the efficacy of using rAAV-mediated gene therapy to replace the disrupted RPE65 gene. The potential for rAAV-mediated gene treatment of LCA was then analyzed by determining the pattern of RPE65 expression, the physiological and histological effects that it produced, and any improvement in visual function. 相似文献74.
根据已报道的植物鲨烯环氧酶(SE)基因特异性引物克隆竹节参SE基因.结果表明,克隆得到竹节参SE全长为1 632 bp,编码539个氨基酸,命名为PjSE.生物信息学分析指出,PjSE基因的氨基酸序列与人参属植物人参、三七、越南人参的同源性依次为99%、98%和98%.推测PjSE基因定位于线粒体(mTP)、叶绿体(cTP)和分泌途径(SP).PjSE基因存在保守结构域FAD结合位点,含4个跨膜结构域和7个motif结构位点.PjSE蛋白二级结构以无规则卷曲(Random coli)和α-螺旋(Alpha helix)为主要结构元件,延伸链(Extended strand)和β转角(Beta turn)分散于整个蛋白质中,百分比依次占40.82%、37.48%、15.77%、5.94%;该蛋白能折叠形成典型的三维结构. 相似文献
75.
Dun-Feng Xu Yu-Jian Liu Yan-Fei Mao Yan Wang Chu-Fan Xu Xiao-Yan Zhu Lai Jiang 《Journal of cellular and molecular medicine》2021,25(8):4124-4135
Thrombocytopenia is independently related with increased mortality in severe septic patients. Renin-angiotensin system (RAS) is elevated in septic subjects; accumulating studies show that angiotensin II (Ang II) stimulate the intrinsic apoptosis pathway by promoting reactive oxygen species (ROS) production. However, the mechanisms underlying the relationship of platelet apoptosis and RAS system in sepsis have not been fully elucidated. The present study aimed to elucidate whether the RAS was involved in the pathogenesis of sepsis-associated thrombocytopenia and explore the underlying mechanisms. We found that elevated plasma Ang II was associated with decreased platelet count in both patients with sepsis and experimental animals exposed to lipopolysaccharide (LPS). Besides, Ang II treatment induced platelet apoptosis in a concentration-dependent manner in primary isolated platelets, which was blocked by angiotensin II type 1 receptor (AT1R) antagonist losartan, but not by angiotensin II type 2 receptor (AT2R) antagonist PD123319. Moreover, inhibiting AT1R by losartan attenuated LPS-induced platelet apoptosis and alleviated sepsis-associated thrombocytopenia. Furthermore, Ang II treatment induced oxidative stress level in a concentration-dependent manner in primary isolated platelets, which was partially reversed by the AT1R antagonist losartan. The present study demonstrated that elevated Ang II directly stimulated platelet apoptosis through promoting oxidative stress in an AT1R-dependent manner in sepsis-associated thrombocytopenia. The results would helpful for understanding the role of RAS system in sepsis-associated thrombocytopenia. 相似文献
76.
77.
Steven P. Govek Celine Bonnefous Jackaline D. Julien Johnny Y. Nagasawa Mehmet Kahraman Andiliy G. Lai Karensa L. Douglas Anna M. Aparicio Beatrice D. Darimont Katherine L. Grillot James D. Joseph Joshua A. Kaufman Kyoung-Jin Lee Nhin Lu Michael J. Moon Rene Y. Prudente John Sensintaffar Peter J. Rix Nicholas D. Smith 《Bioorganic & medicinal chemistry letters》2019,29(3):367-372
Potent estrogen receptor ligands typically contain a phenolic hydrogen-bond donor. The indazole of the selective estrogen receptor degrader (SERD) ARN-810 is believed to mimic this. Disclosed herein is the discovery of ARN-810 analogs which lack this hydrogen-bond donor. These SERDs induced tumor regression in a tamoxifen-resistant breast cancer xenograft, demonstrating that the indazole NH is not necessary for robust ER-modulation and anti-tumor activity. 相似文献
78.
79.
Berahovich RD Lai NL Wei Z Lanier LL Schall TJ 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(11):7833-7840
To help understand the role of chemokines in NK cell trafficking, we determined the chemokine receptor profiles of three different human NK cell lines and freshly isolated primary human NK cells. The cell lines overlapped in their chemokine receptor profiles: CXCR3 and CXCR4 were expressed by all three lines, whereas CCR1, CCR4, CCR6, CCR7, and CX3CR1 were expressed by only one or two of the lines, and no other chemokine receptors were detected. Freshly isolated primary NK cells were found to express CXCR1, CXCR3, and CXCR4, and to contain subsets expressing CCR1, CCR4, CCR5, CCR6, CCR7, CCR9, CXCR5, and CXCR6. With the exception of CCR4, these chemokine receptors were expressed at higher percentages by CD56(bright) NK cells than by CD56(dim) NK cells. In particular, CCR7 was expressed by almost all CD56(bright) NK cells but was not detected on CD56(dim) NK cells. CCR9 and CXCR6 have not been described previously on primary NK cells. These results indicate that within both the CD56(bright) and CD56(dim) NK cell populations, subsets with the capacity for differential trafficking programs exist, which likely influence their functions in innate and adaptive immunity. 相似文献
80.
Combined chemo-gene therapy is one of the treatment modalities that have attracted extensive research interests; however, there is little information regarding the influence of drug application on gene transfer. This study bridges this gap by examining how chemotherapeutic drugs (teniposide, cis-diamminedichloroplatinum(II) and temozolomide) interfere with polyplex formation and transfection of chitosan-graft-poly(ethylenimine). Our results indicate that the degree of drug interference varies with the mechanism of drug action, with the transgene expression being severely suppressed when the plasmid is co-delivered with cis-diamminedichloroplatinum(II) or teniposide but not temozolomide. In addition, the interference with transfection by drugs varies with different gene/drug co-formulations. This is the first study to evidence that, though combined chemo-gene therapy has therapeutic potential, some chemotherapeutic drugs may reduce the treatment efficiency of gene therapy. 相似文献