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Yang H  Chen Y  Shi J  Guo J  Xin X  Zhang J  Wang D  Shu Y  Qiao C  Chen H 《Veterinary microbiology》2011,152(3-4):229-234
Influenza A (H1N1) virus has caused human influenza outbreaks in a worldwide pandemic since April 2009. Pigs have been found to be susceptible to this influenza virus under experimental and natural conditions, raising concern about their potential role in the pandemic spread of the virus. In this study, we generated a high-growth reassortant virus (SC/PR8) that contains the hemagglutinin (HA) and neuraminidase (NA) genes from a novel H1N1 isolate, A/Sichuan/1/2009 (SC/09), and six internal genes from A/Puerto Rico/8/34 (PR8) virus, by genetic reassortment. The immunogenicity and protective efficacy of this reassortant virus were evaluated at different doses in a challenge model using a homologous SC/09 or heterologous A/Swine/Guangdong/1/06(H1N2) virus (GD/06). Two doses of SC/PR8 virus vaccine elicited high-titer serum hemagglutination inhibiting (HI) antibodies specific for the 2009 H1N1 virus and conferred complete protection against challenge with either SC/09 or GD/06 virus, with reduced lung lesions and viral shedding in vaccine-inoculated animals compared with non-vaccinated control animals. These results indicated for the first time that a high-growth SC/PR8 reassortant H1N1 virus exhibits properties that are desirable to be a promising vaccine candidate for use in swine in the event of a pandemic H1N1 influenza.  相似文献   

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Isolation of H13N2 influenza A virus from turkeys and surface water.   总被引:1,自引:0,他引:1  
This is the first report of the isolation of H13N2 avian influenza virus (AIV) subtype from domestic turkeys. This subtype was also isolated from nearby surface water. The observation of large numbers of gulls in close association with turkeys on range before the virus isolations suggests that this virus subtype was transmitted from gulls to range turkeys. Turkey flocks infected by this virus subtype did not show any clinical signs of the disease, although seroconversion did occur. The H13N2 isolates were found to be non-pathogenic in chickens.  相似文献   

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We compared the efficacy of 3 commercial vaccines against swine influenza A virus (SIV) and an experimental homologous vaccine in young pigs that were subsequently challenged with a variant H3N2 SIV, A/Swine/Colorado/00294/2004, selected from a repository of serologically and genetically characterized H3N2 SIV isolates obtained from recent cases of swine respiratory disease. The experimental vaccine was prepared from the challenge virus. Four groups of 8 pigs each were vaccinated intramuscularly at both 4 and 6 wk of age with commercial or homologous vaccine. Two weeks after the 2nd vaccination, those 32 pigs and 8 nonvaccinated pigs were inoculated with the challenge virus by the deep intranasal route. Another 4 pigs served as nonvaccinated, nonchallenged controls. The serum antibody responses differed markedly between groups. After the 1st vaccination, the recipients of the homologous vaccine had hemagglutination inhibition (HI) titers of 1:640 to 1:2560 against the challenge (homologous) virus. In contrast, even after 2nd vaccination, the commercial-vaccine recipients had low titers or no detectable antibody against the challenge (heterologous) virus. After the 2nd vaccination, all the groups had high titers of antibody to the reference H3N2 virus A/Swine/Texas/4199-2/98. Vaccination reduced clinical signs and lung lesion scores; however, virus was isolated 1 to 5 d after challenge from the nasal swabs of most of the pigs vaccinated with a commercial product but from none of the pigs vaccinated with the experimental product. The efficacy of the commercial vaccines may need to be improved to provide sufficient protection against emerging H3N2 variants.  相似文献   

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Two hundred and twelve dog cadavers belonging to different breeds were examined, to investigate the formation of the femoral, obturator and the sciatic nerve. Besides the commonly described formation patterns of the mentioned nerves, some variations were also found. These variations were not gender-related, but on the other hand we discovered a certain correlation between the variations appearing in the formation of the femoral, obturator and the sciatic nerve. In 74.05% of cases, the femoral nerve was formed from ventral branches of the 4th, 5th and 6th lumbar nerve, and 16.98% of the dogs had the nerve formed from ventral branches of the 3rd, 4th and 5th lumbar nerve. Many dogs (i.e. 2.30%) had the femoral nerve formed from the ventral branches of the 5th, 6th and 7th, the 3rd, 4th, 5th and 6th or the 4th, 5th, 6th and 7th lumbar nerve, respectively. In 1.88% of dogs in particular, the femoral nerve was formed from ventral rami of the 4th and 5th lumbar nerve. In 66.98% of the examined dogs, the obturator nerve was formed from the ventral branches of the 4th, 5th and 6th lumbar nerve, followed by 16.59% of the dogs with the obturator nerve formed from the ventral rami of the 4th and 5th lumbar nerve and 9.43% of dogs in which the nerve was formed from the ventral branches of the 5th and 6th lumbar nerve. In 4.71% of dogs, the obturator nerve was formed from the ventral rami of the 4th, 5th, 6th and 7th lumbar nerve, while only 2.30% of the examined dogs had the same nerve formed from the ventral branches of the 5th, 6th and 7th lumbar nerve. The sciatic nerve was formed from ventral branches of the 6th and 7th lumbar nerve and the 1st sacral nerve in 86.79% of the dogs. In 5.18% of cases, the same nerve was formed from a junction of the ventral branches of the 7th lumbar and the 1st and 2nd sacral nerve, and, in the same percentage of cases, it was formed from a junction of ventral branches of the 6th and 7th lumbar nerve and the 1st and 2nd sacral nerve. In 2.83% of the dogs, it was formed from a junction of the ventral branches of the 6th and 7th lumbar and the 1st sacral nerve. The correlation of variations established in the formation of the femoral, obturator and the sciatic nerve was not statistically significant.  相似文献   

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将1段犬瘟热病毒N蛋白氨基酸序列(GenBank编号为:AEV77096.1)与Gen Bank登录的其他氨基酸序列进行比对,分析其同源性;通过DNAStar生物信息学分析软件中的Protean模块及The PredictProtein server在线蛋白分析工具预测犬瘟热病毒N蛋白的理化性质、二级结构、亲水性、表面可及性、柔韧性、抗原指数、跨膜螺旋、蛋白相互作用位点、蛋白功能位点等特性,并预测其B细胞优势抗原表位。结果显示,犬瘟热病毒N蛋白具有规则的二级结构、亲水性、柔韧性片段多,多处于表面可及性大,抗原指数高,蛋白质相互作用位点区域。潜在的B细胞优势抗原表位为1218、6118、6166、24366、243246、410246、410415、421415、421429、434429、434447、452447、452456、480456、480487氨基酸序列。结果表明,本试验预测了犬瘟热病毒N蛋白的B细胞优势抗原表位,为进一步设计犬瘟热病毒的诊断抗原多肽、免疫用抗原多肽和研发血清学检测试剂盒奠定了理论基础。  相似文献   

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犬瘟热病毒N蛋白的B细胞抗原表位预测   总被引:1,自引:0,他引:1  
将1段犬瘟热病毒N蛋白氨基酸序列(GenBank编号为:AEV77096.1)与GenBank登录的其他氨基酸序列进行比对,分析其同源性;通过DNAStar生物信息学分析软件中的Protean模块及The PredictProteinserver在线蛋白分析工具预测犬瘟热病毒N蛋白的理化性质、二级结构、亲水性、表面可及性、柔韧性、抗原指数、跨膜螺旋、蛋白相互作用位点、蛋白功能位点等特性,并预测其B细胞优势抗原表位。结果显示,犬瘟热病毒N蛋白具有规则的二级结构、亲水性、柔韧性片段多,多处于表面可及性大,抗原指数高,蛋白质相互作用位点区域。潜在的B细胞优势抗原表位为12~18、61~66、243~246、410~415、421~429、434~447、452~456、480~487氨基酸序列。结果表明,本试验预测了犬瘟热病毒N蛋白的B细胞优势抗原表位,为进一步设计犬瘟热病毒的诊断抗原多肽、免疫用抗原多肽和研发血清学检测试剂盒奠定了理论基础。  相似文献   

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H9N2亚型禽流感病毒已在世界范围内的禽类中分离确认,并被证实可以传播到人类和低等哺乳类动物。对于它存在的潜在危害已经越来越多地受到关注,相关的研究也相继开展。许多遗传进化的分析为禽或猪流感可以直接感染人提供了证据,通过在人体的适应或与人流感病毒基因重组,可以形成新的病毒株,引起人类流感疫情暴发。文章提示应当密切监控H9N2亚型禽流感病毒,防止人类流感大流行。  相似文献   

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Outbreaks of H7N9 avian influenza in humans in 5 provinces and 2 municipalities of China have reawakened concern that avian influenza viruses may again cross species barriers to infect the human population and thereby initiate a new influenza pandemic. Evolutionary analysis shows that human H7N9 influenza viruses originated from the H9N2, H7N3 and H11N9 avian viruses, and that it is as a novel reassortment influenza virus. This article reviews current knowledge on 11 subtypes of influenza A virus from human which can cause human infections.  相似文献   

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采用RT-PCR方法扩增出马动脉炎病毒核衣壳蛋白基因0RF7,并将其克隆到pMDl8-T载体,构建成重组质粒pMDl8-N,在上海生物工程公司测序。结果表明,所克隆的核衣壳蛋白基因序列与EAVNC-002532株的同源性为99%。表明0RF7是EAV基因组内的保守序列,将0RF7亚克隆到原核表达载体pGEX-6P-1中,构建成重组质粒pGEX-6P-N,用pGEX-6P-N转化表达菌株BL21(DE3),诱导表达后SDS-PAGE和Westernblotting分析表明,克隆在谷胱苷肽硫转移酶(GST)下游的核衣壳蛋白基因与GST获得了高效融合表达,表达的融合蛋白GST-N分子质量约为40ku,为马动脉炎病毒病血清学诊断方法的建立奠定了基础。  相似文献   

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In early 2007, H2N3 influenza virus was isolated from a duck and a chicken in two separate poultry flocks in Ohio. Since the same subtype influenza virus with hemagglutinin (H) and neuraminidase (N) genes of avian lineage was also identified in a swine herd in Missouri in 2006, the objective of this study was to characterize and compare the genetic, antigenic, and biologic properties of the avian and swine isolates. Avian isolates were low pathogenic by in vivo chicken pathogenicity testing. Sequencing and phylogenetic analyses revealed that all genes of the avian isolates were comprised of avian lineages, whereas the swine isolates contained contemporary swine internal gene segments, demonstrating that the avian H2N3 viruses were not directly derived from the swine virus. Sequence comparisons for the H and N genes demonstrated that the avian isolates were similar but not identical to the swine isolates. Accordingly, the avian and swine isolates were also antigenically related as determined by hemagglutination-inhibition (HI) and virus neutralization assays, suggesting that both avian and swine isolates originated from the same group of H2N3 avian influenza viruses. Although serological surveys using the HI assay on poultry flocks and swine herds in Ohio did not reveal further spread of H2 virus from the index flocks, surveillance is important to ensure the virus is not reintroduced to domestic swine or poultry. Contemporary H2N3 avian influenza viruses appear to be easily adaptable to unnatural hosts such as poultry and swine, raising concern regarding the potential for interspecies transmission of avian viruses to humans.  相似文献   

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A one-year influenza A survey was conducted in 10 live bird markets (LBMs) in H5N1 high-risk areas in Thailand from January to December 2009. The result from the survey showed that the occurrence of influenza A virus (IAV) in LBMs was 0.36% (19/5304). Three influenza A subtypes recovered from LBMs were H4N6 (n = 2), H4N9 (n = 1), and H10N3 (n = 16) from Muscovy ducks housed in one LBM in Bangkok. These influenza subtypes had never been reported in Thailand, and therefore such genetic diversity raises concern about potential genetic reassortment of the viruses in avian species in a particular setting. Two influenza A subtypes (H4N6 and H4N9) were isolated from oropharyngeal and cloacal swabs of the same duck, suggesting coinfection with two influenza subtypes and possible genetic reassortment in the bird. In addition, H10N3 infection in ducks housed in the same LBM was observed. These findings further support that LBMs are a potential source of IAV transmission and genetic reassortment.  相似文献   

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