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Colostrum-deprived neonatal Northern fur seal pups (Callorhinus ursinus) were exposed to San Miguel sea lion virus type 5 (SMSV-5) by feeding them fish (Girella nigricans) infected with virus or fish infected with both the sea lion lung worm larvae (Parafilaroides decorus) and virus. Virus infection was demonstrated in 8 of 9 pups, and 1 of these developed a vesicular lesion on the flipper. In this sequence, P decorus larvae exposed to SMSV-5 were fed to G nigricans held at 15 C in a salt water aquarium; 32 days later, these fish were killed, then fed to the fur seal pups. The vesicle developed 22 days subsequent to this and SMSV-5 was reisolated from the lesion. The SMSV-5 was shown to persist for at least 23 days in infected neonatal fur seals. Attempts to establish P decorus infection in Northern fur seal pups were apparently unsuccessful. 相似文献
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将从鸡、鸭和麻雀体内分离到的ＩＢＤＶ用ＳＰＦ鸡胚增殖,采用氯仿抽提、聚乙二醇沉淀和蔗糖密度梯度离心的方法纯化病毒,鉴定结果表明,这种方法可有效地将病毒与杂蛋白分开。用异硫氰酸胍－酚－氯仿－抽提一步法提取病毒ＲＮＡ,电泳分析表明,三种ＩＢＤＶ均由双节段ＲＮＡ组成,大、小基因片段的电泳迁移率毒株间无差异。ＳＤＳ－ＰＡＧＥ分析表明,各ＩＢＤＶ的结构蛋白带谱相同,但各蛋白带的相对百分含量有差异,表明这些不同ＩＢＤＶ分离株的同源性和变异。本文还对ＩＢＤＶ的纯化和变异进行了讨论。 相似文献
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Evolution of avian influenza viruses 总被引：26，自引：0，他引：26
Suarez DL 《Veterinary microbiology》2000,74(1-2):15-27
Although influenza viruses can infect a wide variety of birds and mammals, the natural host of the virus is wild waterfowl, shorebirds, and gulls. When other species of animals, including chickens, turkeys, swine, horses, and humans, are infected with influenza viruses, they are considered aberrant hosts. The distinction between the normal and aberrant host is important when describing virus evolution in the different host groups. The evolutionary rate of influenza virus in the natural host reservoirs is believed to be slow, while in mammals the rate is much higher. The higher rate of evolution in mammals is thought to be a result of selective pressure on the virus to adapt to an aberrant host species. Chickens and turkey influenza virus isolates have previously and incorrectly been lumped together with wild waterfowl, gull, and shorebird influenza viruses when determining rates of evolutionary change. To determine mutational and evolutionary rates of a virus in any host species, two primary assumptions must be met: first, all isolates included in the analysis must have descended from a single introduction of the virus, and second, the outbreak must continue long enough to determine a trend. For poultry, three recent outbreaks of avian influenza meet these criteria, and the sequences of the hemagglutinin and nonstructural genes were compared. Sequences from all three outbreaks were compared to an avian influenza virus consensus sequence, which at the amino acid level is highly conserved for all the internal viral proteins. The consensus sequence also provides a common point of origin to compare all influenza viruses. The evolutionary rates determined for all three outbreaks were similar to what is observed in mammals, providing strong evidence of adaptation of influenza to the new host species, chickens and turkeys. 相似文献
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羊口疮是一种人兽共患传染病，主要由羊口疮病毒（Orf virus，OrfV）感染所致，目前尚无特效药物可治疗。囊膜蛋白是OrfV的主要抗原性蛋白，其机理主要是为病毒侵入宿主细胞创造一系列条件，同时降低宿主免疫力，增强了病毒的毒力。当病毒侵入宿主体内后，宿主会产生抗病毒免疫应答来清除病毒粒子，包括特异性体液免疫和非特异性细胞免疫应答，但主要以非特异性的细胞免疫应答为主。宿主对病毒会产生抗病毒免疫应答，同时病毒也会对宿主的免疫应答形成一种免疫逃避机制，通过该机制来躲避宿主免疫细胞对病毒粒子的捕获和清除，为病毒粒子在宿主体内的增殖、成熟及增强病毒毒力创造了各种条件。作者归纳总结了近年来羊口疮病毒与宿主互作的研究，阐述了OrfV囊膜蛋白的生物学功能、宿主的抗病毒免疫应答、病毒在宿主体内的免疫逃避机制和OrfV的其他一些毒力因子的致病作用，以期为羊口疮病毒的致病机制及疫苗防制研究提供参考。 相似文献
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兽医科学中病毒受体的研究进展 总被引：1，自引：0，他引：1
病毒受体在宿主细胞和病毒的相互作用中起着重要的作用。受体的特性与病毒的宿主范围和组织特异性密切相关,是病毒致病性的关键因素之一。随着分子生物学、细胞生物学、病毒学等学科的发展及新技术的出现,病毒受体研究逐渐成为相关领域的研究热点,其的研究结果可以为阻断病毒与受体的结合提供基础理论,进一步为病毒性疾病的预防与治疗、抗病毒新药物以及疫苗的研制提供新的思路。 相似文献
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Host range relationships and the evolution of canine parvovirus. 总被引：1，自引：0，他引：1
C R Parrish 《Veterinary microbiology》1999,69(1-2):29-40
Canine parvovirus (CPV) is an example of an unusual class of emerging virus-those that gain an altered host range through genetic variation and subsequently become widespread pathogens of their new and previously resistant host species. CPV was first detected in 1978 as the cause of new diseases in dogs throughout the world, when it rapidly spread throughout domestic populations, as well as becoming widespread in wild dogs. CPV was soon shown to be a variant of the long recognized feline panleukopenia virus (FPV), from which it differed in less than 1% at the nucleotide sequence level. Genetic analysis showed that virtually all of the biological differences between CPV and FPV, including the canine host range, were determined by three or four sequence differences in the viral capsid protein gene. Analysis of the atomic structures of the CPV and FPV capsids showed that the differences controlling host range were located within two different structural regions and were exposed on the capsid surface. The CPV which first emerged in 1978 appeared to be derived from a single ancestral sequence, which has allowed the ready analysis of the subsequent evolution of the virus in nature. Sequence analysis has also revealed that CPV strains have undergone a series of evolutionary selections in nature which have resulted in the global distribution of new virus variants. This was first seen in the global replacement between 1979 and 1981 of the original (1978) strain of the virus by a genetically and antigenically variant strain, and the subsequent widespread selection of other variants which have also become globally distributed. The genetic and antigenic variation in the virus strains was also correlated with changes in the host range of the virus, in particular in the ability to replicate in cats, and in canine host range differences seen in tissue culture cells. 相似文献
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猪的繁殖力是决定其生产效率的重要因素,而病毒感染导致的猪流产问题严重影响猪的繁殖效率。了解猪流产相关病毒的致病机制有助于提高猪的繁殖效率,然而大量的研究主要集中在病毒与宿主的蛋白质或基因组DNA上,近年来,长链非编码RNA （long noncoding RNA,lncRNA）从新的视角揭示了病毒与宿主的相互作用,为研究二者之间的互作关系提供了新的途径。lncRNA是一组长度>200 nt的转录本,主要通过与DNA、RNA、染色质和蛋白质互作发挥功能,在某些发育阶段、组织和疾病状态中发生特异性表达,参与机体的多种调控。lncRNA是调控病毒与宿主相互作用的关键因子,在病毒感染宿主后lncRNA发生差异性表达,对应的靶基因富集到炎症和免疫相关的信号通路,参与机体的炎症、免疫和抗病毒反应。深入了解lncRNA在猪流产相关病毒与宿主之间的调控作用,对预防和治疗病毒感染导致的猪流产具有重要意义。作者对lncRNA及其与猪流产相关病毒的关系、宿主lncRNA与病毒的互作及调控通路展开了综述,并对其存在的问题及应用前景进行了展望,以期为猪的抗病育种、猪流产药物的开发和设计及流产类相关疾病的靶点治疗等提供理论依据。 相似文献
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犬瘟热的诊断及其预防免疫的研究进展 总被引：36，自引：7，他引：29
本文对犬瘟热（CD）的诊断、预防免疫和免疫失败的影响因素及犬瘟热病毒（CDV）的宿主范围进行了综述。CDV不仅感染陆生食肉动物，而且也感染水生食肉动物，并且其宿主范围还在不断扩大。CDV感染主要采用病毒分离、特异性病毒抗原或特异性核酸检测等方法确诊。疫苗包括灭活的CDV疫苗、麻疹病毒（MV）异源苗及CDV弱毒活苗。疫苗接种犬的免疫反应主要取决于毒株特性及犬的应答能力，只有弱毒活苗能诱导产生持久而坚强的保护力。尽管多年来CDV弱毒活苗的使用控制了CD的发生，但最近免疫过的犬发生CD的病例并不少见。分析免疫失败的原因，主要是母源抗体干扰、疫苗质量差、其它病毒的免疫抑制以及CDV流行株可能发生了变异等因素的影响。 相似文献
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A procedure for the purification of radioactively labeled bovine viral diarrhea virus was critically evaluated. Purification of virus from artificial mixtures of unlabeled infected and labeled noninfected cells indicated that the extent of purification was approximately 100-fold with respect to host proteins. Residual host proteins were found to contaminate the viral preparation even after extensive purification by differential and isopycnic zonal centrifugation. Co-electrophoresis of 3H-labeled virus with 14C-labeled host cell material in neutral sodium dodecyl sulfate-7.5% polyacrylamide gels provided a means to distinguish viral specific proteins from host cell protein contaminants. Four major electrophoretic components were identified as being of viral origin; molecular weights of the components were estimated from their migration rates relative to protein markers of known molecular weight. Two viral components (VC), VC 1 and VC 3, migrated heterogeneously and had molecular weights of 93,000 to 110,000 and 50,000 to 59,000 daltons, respectively. Molecular weights of VC 2 and VC 4 were 70,000 and 25,000 daltons, respectively. 相似文献
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桑树病毒与病毒病的研究进展(Ⅰ) 总被引：3，自引：1，他引：2
桑树病毒病是危害桑树的一类重要病害。简要介绍已发现的10种桑树病毒病的病原分类、分布及部分病毒病危害桑树的典型病征,重点总结了桑坏死病毒病、桑潜隐病毒病、桑环斑病毒病、桑大斑块花叶病毒病等在病原物分离提取和病毒的基本性状、基因组等基础研究,以及病毒的寄主范围、侵染特征和病害诊断与防治方面的研究进展,为桑树病毒病的综合防治提供指导。 相似文献
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Hueffer K Truyen U Parrish CR 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(3-4):130-135
Canine parvovirus (CPV) evolved as a new pathogen in dogs between 1976 and 1978 from feline panleukopenia virus (FPV). The new virus hit an unprotected population, caused a dramatic pandemic and infected virtually all populations of domestic and wild carnivores worldwide. The great similarity between the two viruses and their differences in host range, both in vivo as well as in vitro, make it a good model system for emerging diseases and host range shifts of viruses. Recent results showed that CPV expanded its host range by binding to the canine transferrin receptor (Tfr). Residues in the capsid protein that had been defined as host range controlling regions also control the binding to the canine transferrin receptor. These residues are located on a raised region of the capsid at the three-fold axis of symmetry. Interestingly, adaption of the new virus to the new host appears to correlate with an improved binding to the Tfr receptor. 相似文献
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口蹄疫(foot-and-mouth disease, FMD)是发生于偶蹄动物的一种急性高度传染性疫病,曾多次在世界范围内暴发流行。FMD致病原口蹄疫病毒(foot-and-mouth disease virus, FMDV)于感染后利用多种策略操纵宿主免疫机制和逃避抗病毒反应,以利于其感染复制。现对最近几年来影响调控FMDV感染与复制的多种因素从不同角度进行总结分析,以期为后续研究提供参考。 相似文献
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病毒进入宿主细胞的机制决定了病毒的趋向性和发病机理,病毒感染细胞包括吸附、穿入、脱壳、复制、组装及子代病毒颗粒的释放等步骤,对病毒入侵机制研究可以为开发有针对性的预防策略提供思路。非洲猪瘟病毒作为一种有囊膜双链DNA病毒,其入侵宿主细胞的机制与其他病毒有一定的相似之处,同样也有其特殊性。目前,人们对非洲猪瘟病毒与宿主细胞相互作用,特别是入侵机制的了解仍然非常有限。为此,本文就ASFV入侵细胞的有关研究进展进行了综述,以期为非洲猪瘟病毒致病机制相关研究提供参考。 相似文献
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Poss M Ross H Rodrigo A Terwee J Vandewoude S Biek R 《Veterinary immunology and immunopathology》2008,123(1-2):154-158
Feline immunodeficiency virus (FIV) is a lentivirus that has been identified in many members of the family Felidae but domestic cats are the only FIV host in which infection results in disease. We studied FIVpco infection of cougars (Puma concolor) as a model for asymptomatic lentivirus infections to understand the mechanisms of host–virus coexistence. Several natural cougar populations were evaluated to determine if there are any consequences of FIVpco infection on cougar fecundity, survival, or susceptibility to other infections. We have sequenced full-length viral genomes and conducted a detailed analysis of viral molecular evolution on these sequences and on genome fragments of serially sampled animals to determine the evolutionary forces experienced by this virus in cougars. In addition, we have evaluated the molecular genetics of FIVpco in a new host, domestic cats, to determine the evolutionary consequences to a host-adapted virus associated with cross-species infection. Our results indicate that there are no significant differences in survival, fecundity or susceptibility to other infections between FIVpco-infected and uninfected cougars. The molecular evolution of FIVpco is characterized by a slower evolutionary rate and an absence of positive selection, but also by proviral and plasma viral loads comparable to those of epidemic lentiviruses such as HIV-1 or FIVfca. Evolutionary and recombination rates and selection profiles change significantly when FIVpco replicates in a new host. 相似文献
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甲型疱疹病毒亚科的疱疹病毒宿主广泛,能感染哺乳类、两栖类和禽类,主要侵害宿主的皮肤、黏膜和神经组织,病毒还会在宿主神经组织潜伏感染,一经感染,难以清除。gC是甲型疱疹病毒亚科的病毒囊膜糖蛋白之一,在病毒感染复制过程中发挥了重要作用。gC与细胞上受体结合帮助病毒吸附至宿主细胞表面、介导低pH条件下病毒入侵上皮细胞、影响病毒基因组的复制。此外,gC帮助病毒逃避补体和抗体的中和,促进病毒的吸附入侵。本文就gC影响病毒感染复制的相关功能进行综述,旨在为研究gC和深入了解甲型疱疹病毒亚科病毒的生命周期,以及gC亚单位疫苗和mRNA疫苗的研究提供参考。 相似文献
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很多宿主细胞在病毒感染下通常会启动caspases通路凋亡途径导致细胞死亡,避免病毒的进一步扩增和传播.但最近的一些研究表明,病毒能利用激活的caspase蛋白酶对自身(非)结构蛋白进行特异性剪切,以利于病毒在细胞内的复制或参与病毒或宿主其他基因的转录调控等过程.作为一个病毒与宿主细胞相互作用关系的新的研究领域,论文对... 相似文献