Résumé
Japanese encephalitis virus (JEV) is a mosquito-borne, zoonotic flavivirus causing viral encephalitis in humans and reproductive disorder in swine. JEV is prevalent throughout China in human; however, spatiotemporal analysis of JEV in Chinese swine herds has not been reported previously. Herein, we present serological and molecular epidemiological results and estimates of prevalence of JEV infections among swine herds in various regions of China. The results suggest that JEV infections are widespread and genotype I and III strains co-exist in the same regions. Therefore, there is an urgent need to monitor JEV infection status among swine herds in China.
Sujets)
Humains , Asiatiques , Chine , Virus de l'encéphalite japonaise (espèce) , Encéphalite japonaise , Encéphalite virale , Flavivirus , Génotype , Épidémiologie moléculaire , Prévalence , Analyse spatio-temporelle , SuidaeRésumé
Fourteen H9N2 avian influenza viruses (AIV) were isolated from sick chickens in China from 1998 to 2008. The sequences of the Non-structural(NS) gene of these isolates were determined by RT-PCR and sequencing, and the entire ORF sequences of NS1 and NS2 protein were obtained.-The homology of these nucleotide sequences and the putative amino acid sequences were compared with several classic reference viruses of H9N2. These isolates were proved to be highly homologous in NS gene (92.9%-99.9% identity) and all belonged to A/Chicken/Beijing/1/1994-like group in the Asia bird-swine branch of allele A of HS gene phylogenetic tree.-According to this study and previous reports of other researchers, NS gene of H9N2 subtype AIV in chickens of China is genetically stable and there is no enough evidence to support the establishment of other sub-lineages in chickens.
Résumé
The σC gene of ARV S1133 was designed to amplify by reverse transcription chain reaction(RTPCR).The σC gene was inserted into the vector pMD19-T,identified by PCR method and restriction enzyme,and sequenced.It showed that the insert cloned gene fragment was the σC gene of ARV.Then the gene was inserted intc the pET32a(+) and indicated that fusion expression vector pET32a-σC was constructed.The recombinant fusion protein was highly expressed in E.coli BL21 induced by 1.0 mmol/L IPTG for 5 hours in the form of inclusion bodies.The weight of recombinant fusion protein molecular is 54 000.Western-blot with ARV antibodies against the fusion protein showed the recombinant protein has a favourable reactivity.