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101.
Duan Yafei Zhang Jiasong Huang Jianhua Jiang Shigui 《Probiotics and antimicrobial proteins》2019,11(3):938-945
Probiotics and Antimicrobial Proteins - The present study investigated the effects of the dietary probiotic Clostridium butyricum (CB) on the growth, intestine digestive enzyme activity,... 相似文献
102.
Liuting Chen Zhaodong Ji Lian Duan Dandan Zhu Jinling Chen Xiaolei Sun Yang Yu Yinong Duan 《Journal of cellular and molecular medicine》2019,23(5):3676-3682
YB1 is a negative regulator in liver fibrosis. We wondered whether SJYB1, a homologous protein of YB1 from Schistosoma japonicum, has an effect on liver fibrosis in vitro. Recombinant SJYB1 (rSJYB1) protein was expressed in a bacterial system and purified by Ni‐NTA His·Bind Resin. A human hepatic stellate cell line, the LX‐2 cell line, was cultured and treated with rSJYB1. The role of rSJYB1 on LX‐2 cells was then analysed by Western blot and luciferase assay. We succeeded in expressing and purifying SJYB1 in a bacterial system and the purified rSJYB1 could be recognized by S japonicum‐infected rabbit sera. Western bolt analysis showed that rSJYB1 inhibited the expression of collagen type I, but had little effect on α‐smooth muscle actin (α‐SMA). Further analysis revealed that rSJYB1 inhibited the activity of collagen α1 (I) (COL1A1) promoter and functioned at ?1592/?1176 region of COL1A1 promoter. Our data demonstrate that rSJYB1‐mediated anti‐fibrotic activity involves inhibiting the activity of COL1A1 promoter and subsequently suppressing the expression of collagen type I in hepatic stellate cells. 相似文献
103.
Bioactive components in the fruits of Ziziphus jujuba Mill. against the inflammatory irritant action of Euphorbia plants 总被引:3,自引:0,他引:3
Chinese jujube (also known as Chinese date) is the fruit of Ziziphus jujuba Mill. (Rhamnaceae). As a famous folk medicine, it is used as antidote in traditional Chinese formula, Shi Zao Decoction, to relieve the drastic inflammatory irritant nature of Euphorbia species. The irritant activities may cause serious adverse effects in clinical practices. This study aimed to investigate the active components of Z. jujuba through the inhibitory effects on the inflammatory cells activated by Euphorbia kansui and prostratin, a phorbol ester isolated from Euphorbia fischeriana. Peritoneal macrophage of rat and splenic lymphocyte (splenocyte) of mouse were selected to evaluate these actions in vitro. Nitric oxide (NO) release of macrophage and the proliferation of splenocyte were examined through Griess method and MTT assay. TNF-α, as an important pro-inflammatory cytokines, was detected with enzyme-linked immunosorbent assay (ELISA) method. Six fractions extracted from Z. jujuba were evaluated and fraction F (triterpene acids fraction) was demonstrated to be the most active part, and then, 21 compounds isolated from Z. jujuba were tested at the concentrations range from 1 μg/ml to 100 μg/ml. The results show that 7 compounds of them are likely to be active compounds concerning to their pronounced inhibitory action on the activated inflammatory cells. These effects might be helpful to attenuate the irritant action of Euphorbiaceae plants and protect the gastrointestinal tissue from potent inflammatory injury, which should be beneficial to some diseases, like inflammatory bowel disease. 相似文献
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105.
Pan Y Yang X Duan J Lu N Leung AS Tran V Hu Y Wu N Liu D Wang Z Yu X Chen C Zhang Y Wan K Liu J Zhu B 《Journal of bacteriology》2011,193(12):3152-3153
Mycobacterium bovis Bacille Calmette-Guérin (BCG) is the only vaccine available against tuberculosis (TB). A number of BCG strains are in use, and they exhibit biochemical and genetic differences. We report the genome sequences of four BCG strains representing different lineages, which will help to design more effective TB vaccines. 相似文献
106.
Effects of the emerald ash borer invasion on the community composition of arthropods associated with ash tree boles in Maryland,U.S.A. 下载免费PDF全文
David E. Jennings Jian J. Duan Dick Bean Kimberly A. Rice Gaye L. Williams Steven K. Bell Aaron S. Shurtleff Paula M. Shrewsbury 《Agricultural and Forest Entomology》2017,19(2):122-129
107.
108.
禽流感病毒H5N1 NS1蛋白是一种非结构蛋白,在病毒感染过程中发挥着重要的作用.构建基因截短的重组蛋白,可为进一步研究NS1不同结构域与宿主蛋白间的相互作用奠定基础.在成功克隆禽流感病毒H5N1全长NS1基因并测序的基础上,将部分截短基因序列克隆到表达栽体pET28a(+)上,构建基因截短的重组表达质粒pET28a-NS1-RBD和pET28a-NS1-ED,转化大肠埃希菌BL21(DE3),阳性重组质粒经IPTG诱导表达后进行SDS-PAGE检测,获得预期蛋白的表达,然后利用Ni-NTA树脂蛋白纯化系统对重组蛋白进行纯化,并通过Western Blotting进一步确认NS1及截短体蛋白的表达.结果表明,实验成功构建禽流感病毒H5N1亚型的NS1蛋白截短体,并在大肠埃希菌中高效表达,这为进一步研究NS1蛋白不同结构域与宿主蛋白的相互作用提供了实验材料,为深入研究NS1蛋白的生物学功能奠定了坚实基础. 相似文献
109.
A monolithic enzymatic microreactor was prepared in a fused-silica capillary by in situ polymerization of acrylamide, glycidyl methacrylate (GMA) and ethylene dimethacrylate (EDMA) in the presence of a binary porogenic mixture of dodecanol and cyclohexanol, followed by ammonia solution treatment, glutaraldehyde activation and trypsin modification. The choice of acrylamide as co-monomer was found useful to improve the efficiency of trypsin modification, thus, to increase the enzyme activity. The optimized microreactor offered very low back pressure, enabling the fast digestion of proteins flowing through the reactor. The performance of the monolithic microreactor was demonstrated with the digestion of cytochrome c at high flow rate. The digests were then characterized by CE and HPLC-MS/MS with the sequence coverage of 57.7%. The digestion efficiency was found over 230 times as high as that of the conventional method. In addition, for the first time, protein digestion carried out in a mixture of water and ACN was compared with the conventional aqueous reaction using MS/MS detection, and the former solution was found more compatible and more efficient for protein digestion. 相似文献
110.
Hao Hu Zhenhua Duan Xiaoran Long Yancu Hertzanu Xiaoqiang Tong Xiaoquan Xu Haibin Shi Sheng Liu Zhengqiang Yang 《PloS one》2015,10(2)
AimsThis retrospective study was carried out to compare the outcomes between elderly (≥70 years of age) and nonelderly patients (<70 years of age) with advanced hepatocellular carcinoma (HCC) who received sorafenib combined with transarterial chemoembolization (TACE).Methods88 patients with a confirmed diagnosis of advanced HCC were enrolled in this study. Of these, 24 elderly patients were matched with 48 nonelderly patients at a 1:2 ratio using propensity score matching to minimize selection bias. The related adverse events and survival benefits were compared between the two groups.ResultsSorafenib combined with TACE was equally well tolerated in both age groups, and grade 3 or 4 adverse events were similarly observed in 54.2% of elderly and 50.0% of nonelderly patients (P = 0.739). There were no significant differences in survival time between the elderly and nonelderly patients (P = 0.876). Significant prognostic factors for overall survival as identified by multivariate analysis were the Child–Pugh score and portal vein invasion.ConclusionsSorafenib combined with TACE may be well tolerated and effective in elderly patients with advanced HCC. Age alone is not a parameter for the treatment of advanced HCC patients. 相似文献