Rapid and standardized methods for detection of foodborne pathogens and mycotoxins on fresh produce

Due to the increase in consumption of fresh produce regarding to the health demand in the last decades, a considerable portion of foodborne outbreaks has been trackbacked to contaminated fresh produce, which have appeared as highly possible vehicles for foodborne outbreaks nowadays. Delays in detection of pathogens and mycotoxins on fresh produce hindered the trace-back investigations in finding the source and revealed the urgent need of rapid and reliable methods. In the frame of this review, we summarized available fast, reliable and standardized methods (conventional, molecular, rapid and recently developed methods) used for detection of the most common foodborne pathogens and mycotoxins which are the most likely causative agents of outbreaks caused by contaminated fresh produce.     

单核细胞增生性李斯特菌毒力基因检测及DNA随机扩增多态性分型

为了解在昌平地区分离的单核细胞增生性李斯特菌（Lm）携带毒力基因的状况和DNA随机扩增多态性（RAPD）分型情况，采用聚合酶链反应（PCR）对28株加进行了溶血素基因（hfy）、与侵袭性有关的卸和prfA基因的测定及RAPD分型。结果3个毒力基因PCR全部呈阳性反应，两株无害加为阴性反应。用RAPD分型，28株加分为12型．A、B两型共9株菌全部来自某肉联厂；C、D两型共10株来自某肉鸡公司；另外9株加有8个RAPD型．分别来自熟肉制品及零售市场。此次实验发现昌平地区在不同时间、不同地点分离的加其RAPD型别变化较大。有多种型别的细菌存在。根据RAPD分型看出肉联厂与肉鸡公司可能存在着内部污染问题。     

Low-Density Lipoprotein Cholesterol/High-Density Lipoprotein Cholesterol Ratio and Carotid Intima-Media Thickness: A Cohort Study in China

Low-density lipoprotein cholesterol to high-density lipoprotein cholesterol (LDL-C/HDL-C) ratio may carry additional information and has been suggested as a better predictor for atherosclerosis progression and cardiovascular disease (CVD) than LDL-C and HDL-C alone. Therefore, we aim to explore the association between LDL-C/HDL-C ratio and high carotid intima-media thickness (CIMT) risk in a large Cohort in Beijing, China. This cohort study included 13,612 adults without high CIMT at first entry and who attended the baseline examination and at least one follow-up annual examination between 2009 and 2016. We used multivariable Cox regression to estimate hazard ratios (HR) with their 95% confidence intervals (CI) for the association between LDL-C/HDL-C ratio and risk of high CIMT. During 37,912 person-years of follow-up, 1996 (1268 men and 728 women) developed high CIMT. Compared with the first quartile of LDL-C/HDL-C ratio, the risk of high CIMT was significantly increased for the fourth quartile of LDL-C/HDL-C ratio (HR = 1.51, 95% CI: 1.29–1.78). We observed a significant association between LDL-C/HDL-C ratio and high CIMT risk comparing LDL-C/HDL-C ratio >2.78 with LDL-C/HDL-C ratio ≤2.78 and significant dose–response relationship between LDL-C/HDL-C ratio and risk of high CIMT. The restricted cubic spline showed a significant nonlinear association between LDL-C/HDL-C ratio and the risk of high CIMT (p_{non-linearity} = 0.009). We identify a significant association between LDL-C/HDL-C ratio and the risk of high CIMT in the Chinese Cohort study. Future studies are needed to evaluate the effectiveness of reducing LDL-C/HDL-C ratio treatment on the development of high CIMT.