黑龙江省分蘖洋葱病毒病原的初步鉴定

黑龙江省分蘖洋葱病毒病发生普遍 ,阿城、宾县、五常的发病率均为 10 0 % ,病情指数分别为6 2 .13% ,71.0 7%和 4 9.87%。典型症状为黄化条纹花叶 ,叶片扭曲畸形、叶尖干枯 ,植株矮缩 ,鳞茎退化变小 ,产量和品质大幅度下降。被分蘖洋葱病毒系统感染的有洋葱、大葱、大蒜和蚕豆 ,局部感染的有千日红、苋色藜。电镜观察表明 ,病体细胞中含有大量线状病毒粒体 ,长度在 30 0～ 14 5 0 nm。通过叶片超薄切片 ,在叶肉细胞质中观察到大量的风轮状、束状、涡轮状和环状内含体 ,叶绿体被破坏。体外抗性测定结果表明 ,致死温度为 5 5～ 6 5℃ ,稀释限点为 10 - 4,体外保毒期为 3d。酶联免疫测试和洋葱黄矮病毒抗血清、韭葱黄条纹病毒抗血清、大蒜复合病毒抗血清呈阳性反应。以上特征证明 ,黑龙江省分蘖洋葱病毒病为几种病毒复合侵染 ,初步鉴定为洋葱黄矮病毒和韭葱黄条纹病毒。     

Generation of recombinant rabies virus ERA strain applied to virus tracking in cell infection

The mechanism of rabies virus(RABV) infection still needs to be further characterized. RABV particle with self-fluorescent is a powerful viral model to visualize the viral infection process in cells. Herein, based on a reverse genetic system of the Evelyn-Rokitnicki-Abelseth(rERA) strain, we generated a recombinant RABV rERA-N/mCherry strain that stably expresses an additional ERA nucleoprotein that fuses with the red fluorescent protein mCherry(N/mCherry). The rERA-N/mCherry strain retained growth property similar to the parent strain r ERA in vitro. The N/mCherry expression showed genetic stability during passage into mouse neuroblastoma(NA) cells and did not change the virulence of the vector. The rERA-N/mCherry strain was then utilized as a visual viral model to study the RABV-cell binding and internalization. We directly observed the red self-fluorescence of r ERA-N/mCherry particles binding to the cell surface, and further co-localizing with clathrin in the early stage of infection in NA cells by fluorescence microscopy. Our results showed that the rERA-N/mCherry strain uses clathrin-dependent endocytosis to enter cells, which is consistent with the well-known mechanism of RABV invasion. The recombinant RABV rERA-N/mCherry thus appears to have the potential to be an effective viral model to further explore the fundamental molecular mechanism of rabies neuropathogenesis.     

黑龙江省大蒜病毒病原鉴定及病毒病发生情况调查

黑龙江省大蒜病毒病的田间症状复杂,研究通过生物学技术、电子显微镜技术和血清学方法相结合对大蒜病毒病原进行鉴定,并对黑龙江省大蒜病毒病的发生情况进行了调查。结果表明,表现花叶症状的大蒜样品中含有韭葱黄条病毒(Leek yellow strape virus,LYSV)和大蒜潜隐病毒(Garlic latent virus,GarLV);表现黄化症状的大蒜样品中含有洋葱黄矮病毒(Onion yellow dwarf virus,OYDV)和大蒜普通潜隐病毒(Garlic common latentvirus,GCLV);表现卷叶症状的大蒜样品中含有GCLV、LYSV和OYDV。黑龙江省大蒜病毒病的发生相当严重,且多数为复合侵染,其中LYSV、GCLV和GarLV的检出率较高。     

Neoplastic transformation of hamster astrocytes in vitro by simian virus 40 and polyoma virus

Astrocytes in cultures of brain cells from fetal or newborn hamsters undergo neoplastic transformation after infection with simian virus 40 or polyoma virus. Subcutaneous or intracerebral inoculation of the transformed brain cells into newborn or adult hamsters produces progressively enlarging astrocytomas at the sites of injection. Astrocytomas produced by polyomatransformed cell lines are histologically better differentiated, but grow more rapidly and metastasize more frequently, than astrocytomas produced by cell lines transformed by simian virus 40. These observations make available in vitro models of virus-induced oncogenesis in astrocytes and provide simple techniques for obtaining astrocytoma cell lines suitable for screening studies of chemical agents effective against astrocytomas.     

甘薯病毒检测技术的改进与组培苗病毒分布特征研究

用NCM-ELISA方法对不同来源的甘薯样品进行6种病毒的检测，结果发现：在农户样品中，以SPFMV的发病最重，检出率高达90％；脱毒后的第一代则以次要病毒检出率为高。同时对三种不同制样方法进行对比，发现以叶柄提取液检出率（66.6％）为最高，比叶片提取液检出率高55.5个百分点。对试管苗进行分节检测的结果表明，病毒分布呈从基部至顶部逐步递减的基本规律，因此在进行试管苗扩繁时，应取顶部以下1-2节，而在进行病毒检测时，则应取靠近培养基的1-2节。     

Influenza B virus in seals

Influenza B virus is a human pathogen whose origin and possible reservoir in nature are not known. An influenza B virus was isolated from a naturally infected harbor seal (Phoca vitulina) and was found to be infectious to seal kidney cells in vitro. Sequence analyses and serology indicated that influenza virus B/Seal/Netherlands/1/99 is closely related to strains that circulated in humans 4 to 5 years earlier. Retrospective analyses of sera collected from 971 seals showed a prevalence of antibodies to influenza B virus in 2% of the animals after 1995 and in none before 1995. This animal reservoir, harboring influenza B viruses that have circulated in the past, may pose a direct threat to humans.     

广西南方水稻黑条矮缩病毒及水稻齿叶矮缩病毒的分子检测

[目的]探索南方水稻黑条矮缩病毒(SRBSDV)和水稻齿叶矮缩病毒(RRSV)的分子检测技术,了解两种病毒在广西的分布,为生产上开展两种病害的防治奠定基础.[方法]用RT-PCR技术检测采自广西各地的水稻、杂草及稻飞虱样品;用CF-11纤维素粉提取水稻茎叶组织中的dsRNA,1.5%琼脂糖凝胶电泳观察dsRNA图谱.[结果]从水稻、稗草、五节芒、李氏禾和白背飞虱样品中获得850 bp左右的SRBSDV序列,从水稻和褐飞虱样品中获得700 bp左右的RRSV序列;首次从五节芒和李氏禾中检测到SRBSDV.SRBSDV单独侵染、SRBSDV和RRSV复合侵染可见8条dsRNA条带,但带谱不一致;RRSV单独侵染可见5条dsRNA带.在供检测的181株水稻样品中,除了来自北海、贵港和梧州市的水稻样品外,其余样品均检测到SRBSDV;除了来白梧州、贺州、玉林、贵港和来宾的水稻样品外,其余样品均检测出RRSV;其中带SRBSDV的样品数占44.8%,带RRSV的样品占21.5%,两种病毒复合感染占11.0%.[结论]研究设计的特异性引物能用于RT-PCR检测SRBSDV和RRSV、水稻样品提取dsRNA能快速直观地鉴定SRBSDV、RRSV单独感染及混合感染水稻.用设计的引物首次检测出SRBSDV的两种新寄主五节芒和李氏禾.     

大豆种传南方菜豆花叶病毒和烟草环斑病毒的GICA-RT-PCR检测

南方菜豆花叶病毒(south bean mosaic virus,SBMV)和烟草环斑病毒(tobacco ringspot virus,TRSV)是我国重要的进境检疫性有害生物,两种病毒均为种传病毒,可随大豆种子实现远距离传播.本研究以这两种病毒的大豆病种子为试材,先用胶体金免疫层析试纸条(GICA)检测,将检测完病毒后的胶体金免疫层析试纸条上的T线和C线剪下,再用RT-PCR的方法将T线和C线上捕获的病毒直接进行扩增,这种将血清学与分子生物学相结合起来所建立的GICA-RT-PCR检测方法,省去了烦琐的总RNA提取的环节,简化了病毒检测的步骤,提高了检测的灵敏度.     

百合病毒检测技术研究进展

笔者对百合病毒的检测技术作了综合评述,主要有植株直接观测法、指示植物接种鉴定法、电镜技术、血清学检测和分子生物学检测技术等,综合应用各项技术使检测更加灵敏、可靠。目前,常用的检测以血清学技术的ELISA为主、分子生物学技术的RT PCR为主。基因芯片检测技术是近几年发展起来高效的检测手段并在植物病毒检测上有广泛的应用前景。     

脱毒马铃薯Y病毒再侵染及运转规律研究

将马铃薯Y病毒 (PVY)分别接种于不同株龄的脱毒马铃薯刚展开的心叶上 ,14天及 2 8天后取样检测植株各部位病毒含量 ,结果表明 ,接种后 14天病毒均运转到匍匐茎或块茎中 ,且其含量均高于其它部位。其次是心叶 (包括生长点 )和接种叶片。病毒含量的高低与接种时植株的株龄大小密切相关 ,株龄越小 ,匍匐茎、块茎和心叶中病毒含量越高。由此可见 ,病毒在植株体内的运转部位 ,主要是生长速度快的匍匐茎、块茎和心叶及生长点。病毒在植株体内的增殖和运转与季节有关 ,春季接种病毒的各部位的病毒含量均比秋季接种的高     

广西蔗区甘蔗花叶病病毒种群分析

[目的]明确引起广西蔗区甘蔗花叶病的病原,为甘蔗抗花叶病育种、种质筛选及病害防控提供科学依据.[方法]从广西主要蔗区采集不同品种显症或不显症甘蔗叶片,提取RNA后采用甘蔗花叶病毒(SCMV)、高粱花叶病毒(SrMV)、玉米矮化病毒(MDMV)和约翰逊草花叶病毒(JGMV)特异引物进行一步法RT-PCR检测,将目的片段克隆并测序;病毒CP基因序列在GenBank数据库中进行比对分析.[结果]在收集的48份样品中检测出SrMV阳性33份,SCMV阳性2份,SCMV和SrMV复合侵染1份,未检测到MDMV和JGMV.花叶病的发病率为75.0％,其中,SrMV、SCMV及两种病毒复合侵染的发病率分别为68.8％、4.2％和2.1％.台糖系列及其他引进品种的甘蔗花叶病感病率较高,桂糖系列品种的感病率相对较低.[结论]甘蔗花叶病已在广西大部分蔗区发生,其致病原以SrMV为主,SCMV零星发生,由SCMV和SrMV复合侵染的甘蔗花叶病发生机率较低.广西蔗区可能存在其他种类病原病毒引起的甘蔗花叶病.     

Effect of cocksfoot mottle virus defective RNA on accumulation of virus capsid protein in wheat plants

The functional role of defective cocksfoot mottle virus RNA in regulating the expression of the viral genome was investigated for testing the hypothesis of its possible participation in transactivation of the synthesis of subgenomic RNA encoding the virus coat protein gene.     

Human T-lymphotropic virus type 4 and the human immunodeficiency virus in West Africa

A new human T-lymphotropic virus (HTLV-4) was recently described in healthy people from Senegal. This virus has many properties in common with members of the human T-lymphotropic viruses, particularly the human immunodeficiency virus or HIV, the etiologic agent of acquired immune deficiency syndrome (AIDS), but does not appear to be associated with immunodeficiency-related disorders. In the present study, serum samples were obtained from 4248 individuals from six West African countries, including Senegal, Guinea, Guinea Bissau, Mauritania, Burkina Faso, and Ivory Coast. These samples, collected during 1985-1987, were from people categorized as healthy control, sexually active risk, and disease populations. All samples were analyzed for reactivity to HTLV-4 and HIV by radioimmunoprecipitation-sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. Evidence for HTLV-4 infection was found in five of the six countries. The seroprevalence varied markedly from country to country. Healthy sexually active individuals in the risk category had the highest levels of HTLV-4 infection compared to individuals in the healthy control category and the disease category, the latter including AIDS patients. The seroprevalence of HIV infection in most of these countries was quite low, although tightly associated with the rare cases of AIDS. The biology of HTLV-4 infection thus differs from that of HIV in Central Africa or the United States and Europe. The presence of these viruses and their different pathogenicities in several countries of West Africa indicate the necessity for serologic assays that will distinguish between them. Further studies of their origin and distribution as well as of their biology will be important in advancing our understanding of AIDS.     

狂犬病病毒G蛋白的过表达及对病毒的抑制

【目的】探究G蛋白在狂犬病病毒(Rabies virus,RABV)复制中的作用,以揭示携带双G基因的重组RABV的Hep-dG与亲代毒株rHep-Flury在神经母细胞瘤(NA)细胞中滴度差异的原因,为RABV致病机制的研究奠定基础。【方法】通过病毒吸附、入侵、荧光定量PCR、Western-blot以及中和抗体阻断等试验,检测G蛋白过表达对IFN-β以及相关因子转录的影响。【结果】Hep-dG感染能显著上调NA细胞中IFN-βmRNA的表达,激活了下游因子STAT1的表达与磷酸化,在较低的感染复数(MOI=0.01)下,Hep-dG感染后24 h即可显著促进IFN-β基因的表达,36 h达到最高水平(P0.001)。该病毒进入细胞后,产生了更多的病毒Leader RNA和RIG-I mRNA,且与IFN-βmRNA的表达高度一致。抗体阻断IFN-β后,Hep-dG在NA细胞中的病毒滴度显著上升(P0.01),约为阻断前的7.9倍,且与亲代毒株rHep-Flury无显著差异。与阴性对照比较,5μg的pH-G质粒转染能刺激IFN-β的转录(P0.05),表明真核表达RABV G蛋白能在一定程度上刺激IFN-β的转录。【结论】本研究初步揭示了G蛋白激活先天性免疫应答的原因和作用。RABV G蛋白的过表达,通过促进病毒Leader RNA的转录,激活了RIG-I介导的IFN-β通路,进而抑制了Hep-dG在NA细胞的繁殖。G蛋白的过表达也对干扰素通路起到一定的作用。     

Polyadenylic acid in Visna virus RNA

Visna virus 70S RNA contains long stretches of polyadenylic acid [poly(A)]. The homogeneity in length of poly(4) regions is observed in 70S RNA from visna virus and all RNA tumor viruses tested, and not with other types of RNA. By this criterion visna virus resembles RNA tumor viruses.     

建兰花叶病毒研究进展(综述)

综述建兰花叶病毒(CyMV)的病害发生、症状表现、寄主范围、病原学、血清学、病害流行学、分子生物学及其检测和防治的研究进展，探讨了须进一步澄清和解决的问题。     

Satellite-like particle of tobacco ringspot virus that resembles tobacco ringspot virus

A satellite-like nucleoprotein serologically indistinguishable from multicomponent tobacco ringspot virus, also resembles it in size, shape, and electrophoretic mobility. Although the protein shell of the nucleoprotein is similar to, if not identical to that of tobacco ringspot virus, each ahell of the nucleoprotein conntains many small strands of nucleic acid, which replicate only in mixed infections with the virus.