人血小板衍生生长因子BB亚型包涵体复性与纯化

目的:优化人血小板衍生生长因子BB亚型(PGDF-BB)包涵体复性方法与纯化条件,获得具有较好生物活性的重组PGDF-BB蛋白。方法:对PGDF-BB包涵体以梯度尿素进行变性,选择最佳包涵体变性浓度;比较不同复性条件下的复性率,稳定PGDF-BB包涵体复性方法;参照该蛋白的理化性质,选择适合PGDF-BB重组蛋白的纯化方法。结果:原核系统内实现了PGDF-BB的高表达;通过优化包涵体复性方法,重组蛋白的包涵体复性率可达40%以上;经过多个纯化方法相结合,PGDF-BB的纯度达到95%。结论:通过实验条件的优化,提高了PGDF-BB包涵体复性率,获得高纯度、高生物活性的重组PGDF-BB蛋白。

Crosstalk between angiotensin Ⅱ and platelet derived growth factor-BB mediated signal pathways in cardiomyocytes

Background Angiotensin Ⅱ （AngⅡ） and platelet-derived growth factor （PDGF）-BB can induce hypertrophy in the cultured rat cardiomyocytes through different signal transduction pathways. Angll stimulates growth through G protein coupled receptor （GPCR）, while PDGF-BB acts via receptor tyrosine kinase （RTK）. Although there has been much development on the individual Angll and PDGF-BB mediated signal pathways, little is known about the interactions between these two factors. Therefore, the crosstalk between Angll and PDGF-BB mediated signal pathways in the rat cardiomyocytes was investigated in this study. Methods Primary culture of neonatal rat ventricular myocytes was prepared. The amount of tyrosine-phosphorylated and non-phosphorylated PDGF-β receptor, Goq/11, and phospholipase C （PLC） β3 were measured by immunoblotting analysis. The statistical analysis was done by one-way ANOVA. Results Tyrosine-phosphorylated PDGF-β receptor was increased by 120.60% at 1 minute and recovered to the control level at 10 minutes after Angll stimulation. Phosphorylation of PDGF-β receptor triggered by Angll was blocked by Iosartan, a specific antagonist of AT1 receptor. PLC inhibitor U73122, protein kinase C （PKC） inhibitor staurosporine （STS） and mitogen-activated ERK activating kinase （MEK） inhibitor PD98059 also inhibited the Angll-induced phosphorylation of PDGF-β receptor. PDGF-BB slightly increased the expression of Gao/11 protein. Conclusion Angll transactivates PDGF-β receptor via AT1 receptor-Gaq/11-PLC-PKC pathway in the rat cardiomyocytes. ERK also participates in the transactivation of PDGF-β receptor triggered by Angll.

PDGF．BB结合CLIF—COFs肝移植术后发生ARDS的预测价值

目的探讨细胞因子结合慢性肝衰竭一器官衰竭评分（CLJF—COFs）能否有效预测乙型肝炎病毒相关慢加急性肝衰竭（HB。ACIF）肝移植术后慢加急性肝衰竭（ARDS）的发生。方法选取首都医科大学附属北京佑安医院2014年7月一2017年10月收治的37例HB—ACIF肝移植患者。按术后是否发生ARDS，发为ARDS组（n=9）及无ARDS组（Tt=28）。采集两组患者手术当天及术后第1、3、5、7天的外周静脉血，应用Bio．Plex 200 LUMINEX液相芯片技术测定27种细胞因子水平。应用logistic回归和受试者丁作曲线分析细胞因子、CLIF—COFs及术前临床、生化指标与术后ARDS的关联性。结果两组问患者年龄、术前感染差异有显著统计学意义（P〈0．05）；ARDS患者术前CLIF—COFs评分高于无ARDS患者（P=0．019）。ARDS组患者术后细胞生长因子（VEGF）、血小板衍生生长因子一BB（PDGF—BB）水平明显降低，而IL一6水平明显升高（P值分别为0．019、0．002、0．038）。受试者1二作曲线提示CLIF—COFs评分和术后PDGF—BB水平可用于预测术后ARDS的发生，两者的受试者_丁作曲线下面积分别为0．728和0．175。CLIF—COFs评分联合术后PDGF．BB预测肝移植术后发生ARDS的曲线下面积为0．913，最大约登指数为0．786，优于两者单独预测ARDS的发生。结论CLIF—COFs评分结合PDGF—BB能够预测HB—ACLF患者肝移植术后ARDS的发生。