Validation of a geographic information system model for mapping the risk of fasciolosis in cattle and buffaloes in Cambodia

Maps showing gradations of risk of fasciolosis due to Fasciola gigantica in Cambodia were produced using geographic information systems (GIS) technology in conjunction with determinants of fasciolosis. A comparison between levels of risk predicted by the maps and field measurements of prevalence in 11 provinces (n=1406) showed general agreement, which suggested the epidemiological determinants and weightings used to produce the maps were appropriate. However, due to logistical constraints, prevalence was measured at the provincial level and animals were not randomly sampled (and thus were unlikely to be representative of variability within provinces). To address this, additional field work was carried out to measure prevalence in more detail--faecal samples were collected from a randomly selected set of animals in four districts across a representative province for areas predicted to be at high risk (n=311), moderate risk (n=268) and no risk (n=262). As with the original field survey, the results show general agreement between prevalence and risk predicted by the maps, with the best fit found for areas predicted to be at high risk.     

Perinatal hypoxia induces anterior chamber changes in the eyes of offspring fish

Hypoxia is a consistent challenge for aquatic animals. It is a pressing environmental problem; hypoxia can cause cranial edema and ovarium dysfunction in fish. Although several studies have reported the effect of hypoxic insult to the visual system, the hypoxic effect on perinatal animals and in particular their offspring has yet to be elucidated. In this study, activated caspase-3 activity was investigated using immunohistochemistry in order to examine the perinatal hypoxic damage in offspring fish. Offspring were divided into groups based on different time points of sacrifice. This allowed assessment of ocular development for different age groups. The results indicated that perinatal hypoxia induced ocular developmental defects in the offspring. The defects took the form of trabecular cell death and fibre degeneration, corneal thinning and lens fibre derangement. A concomitant change in intraocular pressure was recorded by tonometer in the experimental animals compared with the controls. Further investigation should be initiated to develop strategies to prevent developmental disability due to perinatal hypoxia and to increase survivability of the offspring.     

新城疫病毒NP蛋白MHC I类分子限制性T细胞表位研究

为了对新城疫病毒（Newcastle disease virus,NDV）的细胞毒性T细胞（cytotoxic T cell,CTL）表位进行研究,本研究通过在线分析软件预测了NDV弱毒株La Sota和强毒株Herts/33 NP蛋白的MHC I类分子限制性表位,共获得9条可能的表位多肽序列,并人工合成了这些短肽。分别构建了含有La Sota和Herts/33 NP基因的DNA重组质粒并免疫4周龄SPF级C57BL/6小鼠,首免后21 d加强免疫1次,二免后10 d无菌采集脾脏制备脾淋巴细胞悬液,采用ELISpot法测定预测多肽诱导脾淋巴细胞分泌IFN-γ的能力,根据分泌IFN-γ形成的特异性斑点数进行生物统计学分析,发现2条多肽产生的斑点数显著高于无关肽刺激组（P＜0.01）。确定了针对小鼠H-2 kb的限制性T细胞抗原表位的2条多肽。这些可用于合成特异性的MHC-肽四聚体,为后续研究NDV与树突状细胞（dendritic cells,DC）及T淋巴细胞之间的免疫抑制机制提供重要保障。     

A Comparison of Elevated Blood Parameter Values in a Population of Thoroughbred Racehorses

In racing Thoroughbred horses, blood cell counts and key biochemistry parameters are used to monitor horse health during training. The most common measure is total white blood cell (WBC) count, usually coupled with estimates of the relative abundance of the five main types of WBC. However, WBC can go down and up when challenged, making interpretation difficult. In contrast, a large majority of health issues that impact training should trigger an inflammatory response. In this study, we test the potential for two inflammatory biomarkers, fibrinogen and serum amyloid A (SAA), to provide more reliable indicators of health issues across a large sample of horses in training. We find that although WBC and other cell counts are generally correlated with each other and other biochemistry parameters across their full range of values, fibrinogen and SAA exhibit the greatest concordance among the top 15% of values. Moreover, horses with the top WBC values do not overlap significantly with those having the top fibrinogen and SAA values. Because most horses are healthy, these patterns suggest that natural variation in cell counts and biochemistry largely occlude values that might indicate health issues. In contrast, the subset of unusual horses with elevated levels of both fibrinogen and SAA are strongly suggestive of the expected handful of animals with minor, undetected issues. We conclude that fibrinogen and SAA have excellent potential as biomarkers and are likely to be more informative about conditions relevant to horses in training compared with the widely used WBC.     

RNA病毒感染对应激颗粒的调控作用

哺乳动物细胞受到热休克、氧化应激、营养缺乏或者病毒感染等环境压力时,能够迅速启动细胞的压力应答机制,终止细胞内的蛋白翻译,在这个过程中,往往会形成应激颗粒。应激颗粒作为胞浆中终止活动的翻译起始复合物的聚集产物,在细胞的基因表达和内平衡中发挥着重要的作用。尤其是当病毒感染细胞时,应激颗粒的形成可以使细胞的蛋白翻译水平大大降低,从而抑制病毒的复制。然而在病毒的长期进化过程中,也衍生出了对抗细胞压力应答的相应机制,有些病毒甚至可以利用应激颗粒中包裹的沉默的转录本促进自身的复制。本文将着重就RNA病毒对应激颗粒的调控以及最近提出的压力应激与先天性免疫之间的关系做一综述。     

利用PiggyBac转座系统构建稳定表达鹅RIG-I的DF-1细胞系

维甲酸诱导基因-I(retinoic acid inducible gene-I,RIG-I)是最近几年发现的一种细胞内模式识别受体,能够特异性的识别并结合病毒RNA,进而发挥抗病毒效应。RIG-I在进化中相对保守,但已有报道和我们的前期研究显示:家禽中鸭和鹅体内均有RIG-I受体,但鸡却缺乏RIG-I受体。为了研究这种天然缺失对鸡是否有不利影响,本研究利用PiggyBac转座系统将鹅源RIG-I转染入鸡胚成纤维细胞系DF-1,两次亚克隆后获得单个克隆,以荧光、RT-PCR及Western blot进行鉴定,最终获得稳定表达鹅RIG-I的DF-1细胞系,为进一步研究鸡的先天性免疫机制和鹅RIG-I的功能打下基础。     

HeLa细胞中泛素蛋白酶体系统对新城疫病毒复制的影响

本文主要对细胞的泛素-蛋白酶体系统是否参与新城疫病毒(Newcastle disease virus,NDV)的复制过程进行了研究。用NDV感染HeLa细胞,对细胞样品进行Western blot实验,并检测细胞26S蛋白酶体的三种蛋白水解活性变化。同时使用多种泛素-蛋白酶体系统相关的抑制剂处理细胞并做NDV感染,测定细胞上清中病毒TCID50值,比较药物处理与DMSO处理对病毒增殖的影响。结果表明,HeLa细胞在感染NDV后,细胞内泛素化蛋白水平降低,而26S蛋白酶体的三种蛋白水解活性都显著升高;使用泛素-蛋白酶体系统抑制剂后NDV的增殖受到了明显的抑制,证明NDV在HeLa细胞内的增殖与细胞自身的泛素-蛋白酶体系统关系密切。     

Research progress in reprogramming induced pluripotent stem cells

Induced pluripotent stem cells (iPSCs) have been first induced from mouse fibroblasts since 2006, and the research on iPSCs has made great progress in the following years. iPS cell lines were established from different somatic cells through DNA, RNA, protein, and small molecule compounds and various methods of transduction, making the induction of iPSCs more secure and effective, and more attractive prospect of clinical application. In this review, different somatic cell reprogramming, different levels of reprogramming, different transduction pathways, and prospect of application are discussed.     

Enzyme-linked immunosorbent assay (ELISA) detection of infectious pancreatic necrosis virus (IPNV) in culture fluids and tissue homogenates of the rainbow trout, Salmo gairdneri Richardson

Abstract. A double antibody enzyme-linked immunosorbent assay (ELISA) for the detection of infectious pancreatic necrosis virus (IPNV) is described. The sensitivity of the assay reached 10² TCID₅₀ per 0·1 ml of culture fluid. The specificity of anti-IPNV sera and of the assay was confirmed by agar-gel immunodiffusion, by the direct immunoperoxidase technique for the deletion of IPNV in tissue cultures and by the ELISA inhibition test. High values of specific inhibition (over 90% at serum dilutions 1:40–1:2560) and low values of non-specific inhibition (8·4% at serum dilution 1:160) demonstrated the quality of the rabbit anti-IPNV serum. The results of ELISA agreed well with those of virological examinations. The potential of ELISA for investigations of a large series of field samples is discussed.