Identification of domain of protein kinase R interacting with hepatitis C virus core protein

AIM: To observe if hepatitis C virus (HCV) core protein (CP) influences the expression level of protein kinase R (PKR) and to map the direct interaction domain between PKR and CP.METHODS: The expression levels of PKR in Huh-7,Huh-7 transfected with CP plasmid and replicon Huh-7 harboring selecting full length of HCV genome were studied.HCV structure and non-structure proteins in replicon Huh-7 with interferon (IFN) stimulation were compared.Co-immunoprecipitation and glutathione S-transferase (GST) binding assay were done between PKR and CP.RESULTS: PKR expression level in replicon Huh-7 was higher than that in Huh-7 and Huh-7 transfected with CP expression plasmid.PKR was increased but structure and non-structure proteins in replicon Huh-7 were decreased after treated with IFN.The N-terminal 1-180 amino acid of PKR was the key binding site to CP.CONCLUSION: CP directly binds to N-terminal 1-180 amino acid of PKR and leads to constitutive expression of PKR,which interferes signal transfer mediated by PKR.The interaction between CP and PKR might be a novel model of virus protein-cell protein interaction,which might play an important role in the pathogenesis of HCV persistent infection and hepatocellular carcinoma.     

我国养殖大菱鲆病毒性红体病及其流行情况调查

大菱鲆病毒性红体病(Viral reddish body syndrome,VRBS)是一种新发现的感染我国养殖大菱鲆的流行性疾病。本文描述了病鱼的外观症状和解剖病理特征,报道了该病的病原及疾病流行情况调查结果。外观检查发现,病鱼的体表无明显损伤,但腹面沿脊椎骨附近皮下淤血、发红,鳍及鳍基部充血、发红;病鱼贫血,血液凝固性差;肾脏肿大,呈灰白色。组织病理学研究显示病鱼脾组织中存在大量肥大细胞,电镜切片中可见大量平均直径约125nm的二十面体病毒粒子,即大菱鲆红体病虹彩病毒(Turbot reddish body iridovirus,TRBIV)。将过滤除菌的含TRBIV的病鱼脾组织匀浆液,经腹腔注射进行人工感染,感染鱼在3周内的累积死亡率达85．7％,死亡大菱鲆表现出腹面和鳍边发红等外观症状,并在感染鱼脾组织切片中观察到大量同样的病毒粒子,由此证实TRBIV是我国养殖大菱鲆病毒性红体病的病原。疾病流行情况调查显示,该病多在养成期大菱鲆中流行,高发季节为每年的8～12月。     

养虾用水预防病毒病快速处理装置

本装置的设计原理为通过过滤除掉海水中本类疾病的媒介生物,并通过同时的药物消毒杀灭海水中游离的和吸附在悬浮微颗粒上的病毒粒子。装置由水泵、初级滤网、次级滤网、三级滤网、过滤槽及消毒液输入系统组成。初级滤网由40目筛绢制成,用圆钢和铁丝网框架支撑成网箱状,水泵吸水管的进水口设在其中,以滤掉粗大颗粒。次级滤网由80目筛绢制成,成袋状,结扎在水泵排水管的出水口上,悬垂在过滤槽中央,用以滤去较大浮游动物。三级滤网由200～220目筛绢制成,由圆钢和铁丝网制成的框架支撑,设置在过滤槽中,用以滤去较小浮游动物。消毒液输入系统由药液容器、药液导入管及调节阀等部分组成,用于将计算浓度的药液(次氯酸钠)输入处理水中,达到消毒目的。过滤槽为14m^3的一套装置,可维持流量为300m^3／h的水泵正常工作。次级和三级滤网一般要4～10h更换和处理1次．     

灭活菌苗免疫的中华倒刺鲃外周血免疫指标的变化

以温和气单胞菌灭活菌苗为免疫原,平均体重(100±25)g的健康中华倒刺鲃为实验对象,免疫组腹腔注射0.2mL浓度为1.0×108CFU/mL的免疫原,对照组注射等量灭菌生理盐水,分别在单次注射0、1、2、4、7、14、21、28、35d后随机从两组各取6尾实验鱼,尾静脉采血,测定外周血的血细胞数量、白细胞分类计数、吞噬活性、抗体效价和蛋白质含量等免疫指标的变化,第35天活菌攻毒。结果表明:温和气单胞菌灭活菌苗(F-AS)可诱导中华倒刺鲃红细胞和白细胞数量增加,并引起各种白细胞分类百分比变化,提高吞噬活性和抗体效价,血清中总蛋白及球蛋白含量增加,红细胞也具有免疫功能,灭活茵苗的相对免疫保护力达65.21%。免疫早期(第1周)主要是红细胞、单核细胞和中性粒细胞数量明显增加,吞噬细胞的吞噬活性迅速提高,吞噬百分比和吞噬指数第4天达峰值;随后则是淋巴细胞大量增殖,第21天淋巴细胞、抗体效价及球蛋白达峰值。可见灭活菌苗通过促进中华倒刺鲃血细胞增殖、提高吞噬细胞的吞噬活性、产生特异性抗体等方式提高免疫保护力;免疫早期非特异性细胞免疫起重要作用,之后特异性免疫起主要作用。     

中药复方抗病毒复配剂对太子参病毒病防效及产质量的影响

根据中医组方理论形成太子参抗病毒1号及3号中药复方复配剂,其余根据文献记载药用植物化学成分组合叠加形成太子参抗病毒相应药用植物复配剂。选用连作2年太子参种植地块,通过完全区组小区试验考察不同处理对太子参病毒病防效及产质量的影响。结果表明,抗病毒1号中药复配剂（以下简称抗病毒1号复配剂）处理的太子参病毒病发生率比对照降低63.37%(P<0.01),病指比对照降低90.61%,防效最高(90.63%,P<0.01),其余4个配方对病毒病防效均超过80%。对病指在5级以上的太子参植株,施用抗病毒1号复配剂1次后可防止病毒病继续扩散,3次后感染病毒病太子参叶片可恢复正常,5次后叶片病斑和感病症状完全消失,植株恢复正常生长。抗病毒1号及3号复配剂处理产量分别比对照提高了197%及159%(P<0.01),其余处理产量分别提高68%、69%、68%(P<0.01)。抗病毒1号和3号复配剂对太子参总多糖及环肽B含量均有较好提升作用,提高总多糖含量效果最好的处理是抗病毒1号复配剂（提高14%）;提高环肽B效果最好的处理是抗病毒3号（提高11%）。综合来看,抗病毒1号复配剂在防控已经发生的病毒病及提升产质量具有显著效果,选取抗病毒1号复配剂进入下一轮试验。根据中医理论与技术方法形成的配方综合表现好于单纯将具有抗病毒活性中药材叠加,尤其利于提高药材品质。本研究为太子参有效防治及治疗病毒病提供了有机级别多效合一的防治措施。     

牛病毒性腹泻病毒RT—PCR检测方法研究

【目的】建立快速、简便、特异的检测牛病毒性腹泻病毒抗原的RT-PCR方法;【方法】根据已发表的牛病毒性腹泻病毒株(BVDV)5’端非编码区保守序列设计合成了两条引物,应用RT-PCR技术对两株BVDV标准株(OregonC24V and NADL)进行基因扩增,对扩增产物进行酶切鉴定。同时设猪瘟兔化弱毒疫苗株、轮状病毒株、MDBK细胞作对照;【结果】两株BVDV标准株均扩增出了长度为325bp的片段,扩增产物经酶切后形成长度为111bp和214bp两条片段,而对猪瘟兔化弱毒疫苗株、轮状病毒株、MDBK正常细胞扩增均为阴性,与预期结果一致。【结论】PCR检测方法可以快速准确地对牛病毒性腹泻-黏膜病作出诊断。该方法的敏感性可高达10-1TCID50。     

Caprine herpesvirus-1-specific IgG subclasses in naturally and experimentally infected goats

Enzyme-linked immunosorbent assays (ELISAs) were developed to detect caprine herpervirus-1 (CpHV-1)-specific IgG1 and IgG2 in sera from 43 naturally infected goats. The analysis of the IgG subclasses showed a dual pattern of distribution in seropositive goats with a major group of animals (36 out of 43) exhibiting significantly higher levels of IgG2 over IgG1 and a minor group (7 out of 43) possessing equal levels of IgG1 and IgG2. Four goats were experimentally infected with a virulent CpHV-1 Ba.1 strain by the intranasal or the intravaginal route and the kinetics of appearance of CpHV-1-specific IgG, IgG1 and IgG2 in the serum were studied. Two weeks following infection, both IgG1 and IgG2 levels increased although convalescent sera (i.e., collected 5–8 weeks post-infection) showed a clear prevalence of the IgG2 subclass. To determine the contribution of the different IgG subclasses to herpesvirus immunity, serum neutralization (SN) assays were performed in both naturally and experimentally infected goats. The kinetics of SN showed that neutralization activity was mainly associated to the IgG1 subclass and this was also confirmed in naturally infected goats. The results are discussed from the standpoint that the profile of the IgG subclasses is instrumental to study immune responses to CpHV-1 and that vaccination strategies may benefit from this information.     

Rapid methodology for antigenic profiling of FMDV field strains and for the control of identity, purity and viral integrity in commercial virus vaccines using monoclonal antibodies

Monoclonal antibodies (MAbs) developed against different foot-and-mouth disease virus (FMDV) vaccine strains were extensively used to study any possible antigenic variations during vaccine production in Argentine facilities. Additionally, a typing ELISA using strain specific MAbs was developed to detect potential cross contaminations among FMDV strains in master and working seeds with high specificity and sensitivity and to confirm strains identity in formulated vaccines. This assay was carried out for the South American strains currently in use in production facilities in Argentina (A24/Cruzeiro, A/Argentina/01, O1/Campos and C3/Indaial) and for the strain O/Taiwan, produced only for export to Asia. These non-cross reactive MAbs were also used to analyze the integrity of viral particles belonging to each one of the individual strains, following isolation of 140S virions by means of sucrose density gradients from the aqueous phase of commercial polyvalent vaccines. Antigenic profiles were defined for FMDV reference strains using panels of MAbs, and a coefficient of correlation of reactivity with these panels was calculated to establish consistent identity upon serial passages of master and production seeds. A comparison of vaccine and field strain antigenic profiles performed using coefficients of correlation allowed the rapid identification of two main groups of serotype A viruses collected during the last FMD epidemic in Argentina, whose reactivity matched closely to A/Argentina/2000 and A/Argentina/2001 strains.     

鸭病毒性肝炎病毒的分离与鉴定

从长春地区某鸭场送检的疑似鸭病毒性肝炎的病例,采取病鸭肝脏分别进行细菌、病毒分离,结果分离到1株病毒,经病毒回归试验及血清学试验等方法,鉴定该病毒为Ⅰ型鸭肝炎病毒,但与标准株接种鸡胚产生的病变有一定的差别。