目的 研究乙型肝炎病毒X蛋白(HBx)调节细胞内钙离子可能的分子机制,揭示乙型肝炎病毒(HBV)诱导肝癌的可能途径.方法 培养人胚肾细胞(HEK293),取第2代HEK293细胞共转染HBx基因、钙释放激活钙通道蛋白1(Orai1)基因或者间质相互作用因子1(STIM1)基因,免疫共沉淀(co-IP)实验观察细胞内蛋白结合情况,并使用谷胱甘肽巯基转移酶(GST)pull-down实验研究HBx与Orai1作用位点,使用钙离子测量/成像系统检测HBx蛋白对细胞内钙离子的影响.结果 转染后细胞生长状态良好,co-IP实验结果显示HBx蛋白在细胞内可以与Orai1蛋白结合,GST pull-down实验显示HBx蛋白可以与Orai1蛋白C末端结合,钙离子测量/成像系统检测显示HBx蛋白可升高活细胞钙内流.结论 HBx蛋白通过与细胞膜钙离子通道Oria1结合蛋白的C末端结合,增加细胞钙内流,扰乱细胞内钙离子平衡,从而影响细胞增殖等活性.

<正>沙门菌是肠杆菌科的重要致病菌属,也是引起细菌性食物中毒的主要致病菌之一[1],因此,寻找一种快速准确鉴定沙门菌的检测方法尤显重要。目前国内沙门菌检测仍以常规分离培养、生化鉴定为主,而生化鉴定的前提就是在选择性平板上挑取可疑单菌落。木糖赖氨酸脱氧胆盐琼脂

Objective Establish an analytical method of Red 2G in meat product by high performance liquid chromatography(HPLC).Methods Red 2G in meat product was extracted by ethylate-ammonia solution and purified by polyamide,then analyzed with HPLC-PDA.Results The standard curve showed good linearity in the range of 1.00-20.00 μg/ml;the LOD was 0.1 mg/kg;the average recovery was between 79.9%-84.4%.The RSD was 2.20%-6.45 %(n=6).Conclusion This method is suitable for analysis of Red 2G in meat product with high selectivity and sensitivity.

Objective Estrogenic activity of animal-origin food in a city was studied to comprehensively evaluate the pollution by environmental estrogen.Methods The analysis was carried out through the combination of the recombinant yeast estrogen screen(YES) and high performance liquid chromatography-Tandem mass spectrometry(LC-MS/MS) method.Results The results obtained from the YES were expressed as biological estradiol equivalent(EEQbio),which ranged from 6.11 to 25.45 ng/g.In addition,17β-estradiol(E2) and bisphenol A(BPA) were detected in all samples by the LC-MS/MS.17α-ethinylestradiol(EE2) was also detected in most of the samples,and the concentration range was(2.87~5.05) ng/g,(0.48~3.57) ng/g and(1.23~7.38) ng/g respectively.The chemical estradiol equivalent(EEQchem) of samples calculated from the chemical method ranged from 3.15 to 15.14 ng/g.There was some correlation of the estradiol equivalent values measured by the YES and the LC-MS/MS(R2=0.443).Conclusion Certain degree of estrogenic activity was detected in all the samples,and the combination of the biological experiment and chemical analysis could more effectively evaluate the overall effect and pollution status of the environmental estrogen in animal food.

<正>组建委员会《食品安全法》第二十三条规定:"食品安全国家标准应当经食品安全国家标准审评委员会审查通过。"为贯彻落实《食品安全法》对食品安全标准工作的要求,卫生部于2010年1月20日组建了第一届食品安全国家标准审评委员会。该委员会在原卫生部食品卫生标准专业委员会和全国食品添加剂标准化技术委员会的基础上,吸纳了医学、农业、食品、营养等方面的专家和食品安