Differential activation of host cell signalling pathways through infection with two variants of influenza A/Puerto Rico/8/34 (H1N1) in MDCK cells

In cell culture-based influenza vaccine production, few efforts have been undertaken to characterise virus–host cell interactions in detail. Two influenza virus strains that grew to different virus titres, and differed in virus dynamics, apoptosis induction and proteome changes were observed.     

姜黄素抑制人肝癌细胞BEL-7402中VEGF和HIF-1α表达通过PI3K／AKT／FRAP信号传导通路

目的探讨MAPK和PI3K信号传导通路在姜黄素调节VEGF和HIF-1α表达中的作用。方法分别加入LY29400225μmol／L、50μmol／L，U012610μmol／L、20μmol／L，rapamycin 5ng／ml、10ng／ml处理人肝癌细胞BEL-7402，30min后加入姜黄素10μmol／L，对照组单独加入0、10μmol／L姜黄素，缺氧环境中培养6h后，行RT—PCR和Western Blot检测VEGF蛋白、mRNA和HIF-1α蛋白表达；分别加入不同浓度的的姜黄素以及LY294002 25 μmol／L处理人肝癌细胞BEL-7402，缺氧环境中培养6h后，行Western Blot检测磷酸化AKT和总AKT蛋白表达。结果姜黄素10μmol／L＋LY29400225μmol／L组、姜黄素10μmol／L＋LY294002 50 μmol／L组、姜黄素10μmol／L＋rapamycin 5 ng／ml组、姜黄素10μmol／L＋rapamycin 10 ng／na组HIF-1α蛋白、VEGF蛋白、mRNA表达分别与姜黄素10μmol／L组相比降低，差异有统计学意义（P〈0．01）；而姜黄素10μmol／L＋U012610μmol／L组、姜黄素10μmol／L＋U0126 20 μmol／L组HIF—1α蛋白、VEGF蛋白、mRNA表达分别与姜黄素10μmol／L组相比差异无统计学意义（P〉0.05）；不同浓度的姜黄素、LY294002 25 μmol／L处理的人肝癌细胞BEL-7402缺氧6h后磷酸化AKT蛋白表达逐渐降低，LY294002 25 μmol／L可以基本阻断磷酸化AKT蛋白的表达，而对总AKT蛋白表达无明显变化。结论姜黄素对人肝癌细胞BEL-7402中HIF-1α蛋白和VEGF的表达通过P13K／AKT／FRAP信号传导通路。     

^60Co治疗机计算机辅助操作系统的原理与实现

本文介绍计算机软件《＾６０Ｃｏ治疗机辅助操作系统》的原理与实现。包括：计算“放射是有关公式；治疗质量控制有关指标及计算公式；系统功能模块；系统操作流程；系统运行环境。     

不同n-3/n-6多不饱和脂肪酸构成比膳食对大鼠一磷酸腺苷活化蛋白激酶表达的影响

目的研究不同n-3/n-6配比脂肪酸对大鼠磷酸腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)蛋白及活性表达的影响。方法58只SD大鼠适应性喂养7d后,尾静脉取血。根据血清总胆固醇水平随机分为:空白(基础饲料);高脂(高脂饲料);高脂1:1(高脂饲料+n-3/n-6=1:1配方油);高脂1:5(高脂饲料+n3/n6=1:5配方油);低脂1:1(脱脂基础饲料+n-3/n-6=1:1配方油);低脂1:5(脱脂基础饲料+n3/n6=1:5配方油)6组,喂养45d,观察大鼠摄食与体重增长。于实验前1d,15d,30d,45d分别各取血测血清总胆固醇水平,于D45处死动物。Western blotting分别分析肝和下丘脑组织中AMPK-α总蛋白及其活性表达。结果添加PUFA的4个比例组血清TC、体重与高脂组相比,显著降低,且低脂2个比例组和高脂1:1组均与高脂1:5组相比有显著差异。添加PUFA的4个比例组均与高脂组相比,大鼠下丘脑AMPK-α总蛋白表达水平明显降低,肝AMPK-α蛋白表达水平均比高脂组明显升高。结论PUFA改善血脂可能是通过增加肝AMPK表达,抑制下丘脑AMPK表达,增加肝脂肪酸氧化和抑制食欲,影响血脂代谢。     

下调LOX基因对肾癌细胞增殖、凋亡及细胞周期的影响及机制研究

目的 探讨LOX对肾癌细胞增殖、凋亡及细胞周期的影响及其作用机制。方法 将si-con、si-LOX质粒分别转染至786-0细胞中,记为si-con组、si-LOX组,转染采用脂质体法。蛋白质印迹（Western Blot）检测赖氨酰氧化酶(LOX)、周期素依赖性激酶4（CDK4）、Bcl-2相关X蛋白（Bax）、B细胞淋巴瘤/白血病-2（Bcl-2）、磷酸化蛋白激酶B（p-Akt）、蛋白激酶B（Akt）表达水平;四甲基偶氮唑盐比色法(MTT)检测细胞活力;流式细胞术检测细胞凋亡和细胞周期。结果 与正常肾小管上皮细胞HK-2相比,肾癌细胞786-0、GRC-1、A498中LOX表达水平显著升高（P＜0.001）。敲减LOX肾癌细胞786-0的活力显著降低（t=8.440,P＜0.001）,786-0细胞的凋亡率显著升高（t=25.628,P＜0.001）,G0/G1期细胞所占比例增加（t=7.211,P＜0.001）,S期细胞所占比例减少（t=13.190,P＜0.001）,786-0细胞中CDK4、Bcl2、p-Akt表达水平显著降低（t=15.660、13.914、12.349,P＜0.001）,786-0细胞中Bax表达水平显著升高（t=22.057,P＜0.001）。结论 敲减LOX能抑制肾癌细胞增殖,促进细胞凋亡,影响细胞周期,其机制可能与PI3K/Akt信号通路有关,可为肾癌的治疗提供新思路。     

Effects of Phosphoethanolamine Supplementation on Mitochondrial Activity and Lipogenesis in a Caffeine Ingestion Caenorhabditis elegans Model

Caffeine intake is strongly linked to lipid metabolism. We previously reported the age-dependent physiological effects of caffeine intake in a Caenorhabditis elegans model. Since nutritional status can actively influence metabolism and overall health, in this study, we evaluated the effect of caffeine intake on lipid metabolism in adult-stage C. elegans. We found that, in C. elegans, fat storage and the level of phosphoethanolamine (PE) were significantly reduced with caffeine intake. In addition, mitochondrial activity decreased and mitochondrial morphology was disrupted, and the expression of oxidative stress response genes, hsp-6, gst-4, and daf-16, was induced by caffeine intake. Furthermore, the level of an energy metabolism sensor, phospho-AMP-activated protein kinase, was increased, whereas the expression of the sterol regulatory element binding protein gene and its target stearoyl-CoA desaturase genes, fat-5, -6, and -7, was decreased with caffeine intake. These findings suggest that caffeine intake causes mitochondrial dysfunction and reduces lipogenesis. Interestingly, these changes induced by caffeine intake were partially alleviated by PE supplementation, suggesting that the reduction in mitochondrial activity and lipogenesis is in part because of the low PE level, and proper dietary supplementation can improve organelle integrity.     

血清及尿液中sFlt-1/PLGF比值的变化与子痫前期相关性研究

目的:研究子痫前期患者及正常对照组孕妇血清及尿液中胎盘生长因子(PLGF)与可溶性络氨酸激酶受体1(sFlt-1)水平变化,探讨血清及尿液中sFlt-1/PLGF比值的变化与子痫前期病情程度的关系,以及尿液中PLGF、sFlt-1水平与血清中PLGF、sFlt-1水平的相关性。方法:采用酶联免疫吸附法检测并比较25例轻度子痫前期患者、20例重度子痫前期患者及20例正常晚期妊娠妇女血清及尿液中sFlt-1/PLGF比值,并分析子痫前期患者及对照组孕妇尿液中sFlt-1、PLGF与血清中sFlt-1、PLGF水平的相关性。结果:对照组血清及尿液中sFlt-1/PLGF值低于轻度子痫前期组,轻度子痫前期组血清及尿液中sFlt-1/PLGF值低于重度子痫前期组,各组之间的差异有统计学意义(P<0.05)。尿液中PLGF、sFlt-1水平与血清中PL-GF、sFlt-1水平成正相关。结论:孕妇血清及尿液中sFlt-1/PLGF比值水平与子痫前期病情程度呈相关性,且尿液中PLGF、sFlt-1水平与血清中PLGF、sFlt-1水平成正相关,可以用尿液中sFlt-1/PLGF比值检测替代血清sFlt-1/PLGF比值预测子痫前期的发生。     

ERK1/2在维生素E琥珀酸酯诱导人胃癌细胞凋亡中的作用

为探讨ERK1 2丝裂素活化蛋白激酶 (MAPK)信号转导途径在维生素E琥珀酸酯 (VES)所诱导的人胃癌SGC 790 1细胞凋亡过程中的作用 ,采用DAPI染色法观察VES诱导细胞凋亡的情况 ,采用WesternBlot法分析VES不同剂量和不同作用时间对ERK1 2磷酸化状态的影响。结果表明 ,VES明显诱导SGC 790 1细胞凋亡 ,2 0 μg mlVES作用 2 4h和 48h后凋亡率分别为 14 .2 %和 89.6%。 5、10、2 0 μg mlVES作用 2 4h时明显降低p ERK蛋白的表达 ;而 2 0 μg mlVES作用于细胞时 ,ERK1 2可瞬时被激活 ,2h时表达下降 ,而后又升高 ,12h达峰值。提示ERK1 2途径可能参与了VES诱导的SGC 790 1细胞凋亡 ,但最终参与调节细胞增殖过程     

Digestion kinetics of potato protein isolates in vitro and in vivo

Abstract

Recently, an industrial process was developed to isolate native protein fractions from potato: a high (HMW) and a low (LMW) molecular weight fraction. Digestion kinetics of HMW and LMW was studied in vitro and in vivo and compared with reference proteins. Under simulated conditions, highest digestion was found for whey protein, followed by soy, pea, HMW, casein and LMW. Ingestion of 20?g of proteins by eight healthy subjects (following a randomized, double-blind, cross-over design) induced a slow and moderate increase with HMW and LMW, while a peaked and high increase with whey protein, in postprandial plasma amino acid levels. Casein gave a similar profile as HMW, with higher levels. Contrary to whey and casein, HMW and LMW did not result in any changes in plasma insulin or glucose levels. This study provides insights in digestion of native potato protein isolates to assist their use as protein sources in food applications.     

Effects of Eicosapentaenoic Acid and Docosahexaenoic Acid on Uncoupling Protein 3 Gene Expression in C2C12 Muscle Cells

Uncoupling protein 3 (UCP3) is a mitochondrial membrane transporter that is expressed mainly in skeletal muscle where it plays an important role in energy expenditure and fat oxidation. In this study, we investigated the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on UCP3 gene expression in C₂C₁₂ muscle cells. EPA and DHA up-regulated UCP3 mRNA level in a dose-dependent manner and similarly increased UCP3 promoter activity in C₂C₁₂ muscle cells. To determine whether AMP-activated protein kinase (AMPK) signaling may also directly regulate UCP3 expression, 5′-amino-4-imidazolecarboxamide-ribonucleoside (AICAR), an AMP analog that activates AMPK, was treated in C₂C₁₂ muscle cells. AICAR showed additive effects with EPA or DHA on the UCP3 promoter activation. These results indicate that EPA and DHA directly regulate the gene expression of UCP3, potentially through AMPK-mediated pathway in C2C12 muscle cells.