猪圆环病毒2型(porcine circovirus type 2,PCV2)被认为是猪圆环病毒相关性系统疾病(PCV2-SD)的主要病原体,在全球范围内广泛传播,给世界养猪业造成了巨大损失,但是有关PCV2的致病机制尚不完全清楚.该文将有关PCV2分子流行病学的研究资料进行了整理,主要包括PCV2的易感动物、传播途径和流行特点等方面,以期为后续研究提供参考.

猪圆环病毒3型是一种新发现的猪圆环病毒血清型,不仅流行广泛,而且与多种猪的疾病相关,已成为世界养猪产业的一个新威胁,因而引发了各国学者的研究热情.本文综述了近年来PCV3在病原学、致病机理等方面的研究进展,以期为了解PCV3在猪相关疾病中的作用以及更好突破疾病防治的难关提供参考资料.

硒(selenium,Se),是一种对人和动物体有重要作用的非金属微量元素,具有抗肿瘤、抗重金属、抗病毒、抗氧化、增强机体免疫力等多种功能.机体的抗氧化能力可作为机体健康的评价标准之一,硒因对提升机体的抗氧化能力有较大作用,一直是抗氧化领域研究的热点之一.本文以国内外最新研究资料为基础,对有机硒、无机硒及纳米硒的抗氧化作用机制研究进行了总结,旨在揭示不同类型硒在抗氧化作用机制上的异同,以期为硒的抗氧化研究提供相关的理论参考,为含硒抗氧化药物及相关硒产品的研发提供理论支撑.

为了解近年来广西容县霞烟鸡的鸡传染性法氏囊病(IBD)发病情况和流行趋势,采用酶联免疫吸附试验(ELISA)对2018年3月至2019年4月期间采自广西容县农村散养户中未免疫过IBD疫苗的245份病鸡血清样品进行了IBDV抗体的检测.结果显示,245份病鸡血清样品中IBDV抗体总体阳性率为46.12％(113/245),且不同日龄、季节、地区的病鸡血清样品中都检测到IBDV抗体的存在,说明IBDV在容县霞烟鸡的鸡群中普遍存在,提示IBDV仍是今后霞烟鸡群疫病防控的重点.

Selenium is a trace element necessary for the growth of organisms. Moreover, selenium supplementation can improve the immunity and fertility of the body, as well as its ability to resist oxidation, tumors, heavy metals, and pathogenic microorganisms. However, owing to the duality of selenium, excessive selenium supplementation can cause certain toxic effects on the growth and development of the body and may even result in death in severe cases. At present, increasing attention is being paid to the development and utilization of selenium as a micronutrient, but its potential toxicity tends to be neglected. This study systematically reviews recent research on the toxicological effects of selenium, aiming to provide theoretical references for selenium toxicology-related research and theoretical support for the development of selenium-containing drugs, selenium-enriched dietary supplements, and selenium-enriched foods.

猪圆环病毒(Porcine circovirus,PCV)是迄今为止能够感染哺乳动物的最小病毒,目前已发现有PCV1、PCV2和PCV3 3种血清型.PCV1于1974年首次在猪肾细胞(PK-15)中发现,可感染猪但对其无致病性;PCV2于1998年首次被分离和鉴定,是引发猪群出现断奶仔猪多系统衰竭综合征(PMWS)、猪皮炎肾病综合征(PDNS)、猪呼吸道疾病综合征(PRDC)等猪圆环病毒相关疾病(Porcine circovirus-associated disease,PCVAD)的主要病原体;PCV3于2016年首次在患有PDNS的母猪和流产胎儿中检测出,随后在亚洲、欧洲、美洲等地区的猪群中被陆续发现,且与PDNS、繁殖障碍、心脏病和多组织器官炎症等有关11-21.研究发现,PCV3不仅传播速度快、范围广,除了可单一感染外还可与其他病原体混合感染,其对世界养猪业造成的潜在威胁已经引起各国学者的密切关注,各国学者纷纷针对PCV3的起源、基因多样性、进化动力学、流行趋势、致病性、在PCVAD中的作用及疫苗研发等相关领域进行了大量研究并取得了许多重要成果.为此,本文对PCV3的流行病学进行综述,以期为其后续研究提供参考.

Quality-of-life improvements have resulted in increasing attention being paid to research on antiaging and antioxidation. Polyphenols are natural antioxidants with excellent biological activities, such as antioxidation and scavenging of free radicals and antiviral activity. Abundant availability and low toxicity of polyphenols have attracted the attention of researchers. In this paper, the antioxidant activities of flavonoids, phenolic acids, stilbenes and lignan polyphenols are analyzed, the corresponding antioxidant mechanisms are investigated, and the antioxidant effects of polyphenols are systematically reviewed. Thus, an effective reference based on the recent literature is compiled for the study of the antioxidant mechanisms of polyphenols that provides a significant theoretical basis for the development of products that are components of polyphenols.

金花茶是山茶科山茶属的常绿灌木或小乔木植物,属于无毒性植物,其花和叶富含多种对人体健康具有重要意义的天然成分,且某些成分能够影响到传染性病毒的生命活动,现已逐渐成为制作花茶、叶茶保健饮品的首选植物资源.论文基于近年来有关金花茶药理作用方面的研究资料,对其抗病毒作用进行了系统性分析,重点阐述了金花茶拮抗几种常见DNA和RNA病毒的机制的最新研究进展,以期为后续金花茶抗病毒作用相关研究提供参考,为开发含金花茶等天然植物生物活性与营养成分的具有保健作用及药用价值的产品提供理论依据.

Background and objectivePalmitic acid (PA), the most common saturated free fatty acid (FFA) in food, is related to obesity-related male infertility. The possible mechanism is PA-mediated inhibition of testosterone secretion. Endoplasmic reticulum (ER) oxidoreductin-1alpha (ERO1α), an oxidase that is localized in the ER, plays an essential role in maintaining ER homeostasis and is related to hormone secretion. However, the role and underlying mechanisms of ERO1α in PA-mediated inhibition of testosterone secretion have not been reported. Material and methodsMurine Leydig tumor cell line 1 (MLTC-1) cells were treated with different doses of PA. Cell viability, testosterone secretion, and ERO1α expression were measured by the Cell Counting Kit 8 (CCK-8) assay, enzyme-linked immunesorbent assay (ELISA), and Western blotting, respectively. Moreover, the expres-sion of ER stress marker proteins (glucose-regulated protein 78 [GRP78] and CCAAT/enhancer-binding protein homologous protein [CHOP]) was also measured after treatment. Subsequently, the expression ofERO1α was knocked down, and cell viability, testosterone secretion, and ER stress were measured after treatment with the PA or the ER stress agonist thapsigargin (TG, an ER stress inducer). Also, testosterone secretion was measured by ELISA when ER stress was inhibited by 4-phenylbutyric acid (4-PBA, an ER stress inhibitor). ResultsPA treatment reduced cell viability, induced ERO1α expression, and enhanced the expression of the ER stress marker GRP78 and CHOP, while ERO1α knockdown inhibits ER stress marker expression, promotes testosterone secretion, and enhances cell viability in PA-treated MLTC-1 cells. In addition, ERO1α knock-down rescued the TG-induced the decrease in testosterone secretion and cell viability. ConclusionsThese findings suggest that PA inhibits testosterone secretion via ER stress and that ERO1α knockdown ameliorates PA-induced decreases in testosterone via ER stress in testicular Leydig cells. Our results indi-cate the necessity of exploring the potential applications of ERO1α as a target gene for restoring fertility in obese men.