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根据南方菜豆花叶病毒(SBMV)两株系B和C的核酸序列设计两对引物,利用RT-PCR可以特异地区分纯化的和0.2g病叶中的两株系,RT-PCR检测SBMV-B的灵敏度为10pg。 相似文献
13.
PRRS ELISA试剂盒检测猪繁殖与呼吸综合征病毒抗体的应用 总被引:2,自引:0,他引:2
利用重组杆状病毒表达的PRRSV核衣壳蛋白作抗原制成ELISA诊断试剂盒,检测人工感染PRRSV猪血清、疫苗免疫抗体和田间血清,并与IDEXX公司生产的试剂盒进行比较。结果表明,该试剂盒在PRRSV感染后8天内就可检出感染性抗体,而用IDEXX公司生产的试剂盒在感染后的18天才检测到感染性抗体,对弱毒疫苗的免疫检测也基本能反映出疫苗的免疫应答状况。对华东地区PRRSV流行病学调查结果表明,PRRSV在国内普遍存在,同时也证明研制的试剂盒,是客观科学调查我国PRRS流行情较理想的检测工具。 相似文献
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Nataa Mehle Maja Kova
Nataa Petrovi
Marua Pompe Novak pela Baebler Hana Kre
i
Stres Kristina Gruden Maja Ravnikar 《Physiological and Molecular Plant Pathology》2004,64(6):19
The aim of this work was to correlate the appearance of the symptoms, multiplication and spread of virus after mechanical inoculation of potato (Solanum tuberosum L.) cultivars showing different levels of susceptibility and sensitivity to Potato virus YNTN (PVYNTN). The potato cultivars used were the resistant cultivar Sante and susceptible cultivars Igor, Pentland squire and Désirée. The spread of the virus PVYNTN in infected plants was monitored using different methods: DAS-ELISA, tissue printing, immuno-serological electron microscopy and real-time PCR. In all three susceptible cultivars, the virus was detected in the inoculated leaves 4–5 days after inoculation. From there virus spread rapidly, first into the stem, then more or less simultaneously to the upper leaves and roots. Real-time PCR was shown to be very sensitive and enabled viral RNA to be detected in non-inoculated leaves of susceptible cultivar Igor earlier than other methods. Therefore, for exact studies of plant–virus interaction, a combination of methods which detect viruses on the basis of their different properties (coat protein, morphology or RNA) should be used to monitor the spread of viruses. 相似文献
15.
2004初从正常鸭群中分离到一株鸭源禽流感病毒,命名为A/Duck/HN/4/2004(H6N2)。经对血凝素基因(HA)序列分析发现HA基因全长为1744bp,共编码566个氨基酸,在裂解位点仅含一个碱性氨基酸-精氨酸(R),符合LPAIV的标准。将所得基因序列与已发表的同一亚型参考序列分析表明,与H6亚型流感HA基因同源性为89.2%-97.1%,经分子遗传演化分析表明本次分离株与香港分离株A/Duck/Hong Kong/3600/99(H6N2)、A/Duck/Hong Kong/3600/99(H6N2)最近。 相似文献
16.
Avian influenza A H5N6 virus is a highly contagious infectious agent that affects domestic poultry and humans in South Asian countries. Vietnam may be an evolutionary hotspot for influenza viruses and therefore could serve as a source of pandemic strains. In 2015, two novel reassortant H5N6 influenza viruses designated as A/quail/Vietnam/CVVI01/2015 and A/quail/Vietnam/CVVI03/2015 were isolated from dead quails during avian influenza outbreaks in central Vietnam, and the whole genome sequences were analyzed. The genetic analysis indicated that hemagglutinin, neuraminidase, and polymerase basic protein 2 genes of the two H5N6 viruses are most closely related to an H5N2 virus (A/chicken/Zhejiang/727079/2014) and H10N6 virus (A/chicken/Jiangxi/12782/2014) from China and an H6N6 virus (A/duck/Yamagata/061004/2014) from Japan. The HA gene of the isolates belongs to clade 2.3.4.4, which caused human fatalities in China during 2014–2016. The five other internal genes showed high identity to an H5N2 virus (A/chicken/Heilongjiang/S7/2014) from China. A whole-genome phylogenetic analysis revealed that these two outbreak strains are novel H6N6-like PB2 gene reassortants that are most closely related to influenza virus strain A/environment/Guangdong/ZS558/2015, which was detected in a live poultry market in China. This report describes the first detection of novel H5N6 reassortants in poultry during an outbreak as well as genetic characterization of these strains to better understand the antigenic evolution of influenza viruses. 相似文献
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The intestinal epithelial cells reside in close proximity to myofibroblasts and microbiota, which are supposed to have an impact on intestinal stem cells fate and to influence processes of tissue maturation and regeneration. Mechanism underlying these phenomena and their diversity among vertebrates can be studied in 3D organoid cultures. We investigated the growth of chicken embryo intestinal epithelial organoids in Matrigel with and without Toll-like receptors (TLRs) stimulation. The organoid cultures contained also some myofibroblasts with potential to promote intestinal stem cell survival. Organoid cells, expressing TLR4, TLR2 type 1 and TLR2 type 2 were incubated with their agonists (lipopolysaccharide – LPS and Pam3CSK4) or co-cultured with Lactobacillus acidophilus bacteria (LA-5). Pam3CSK4 and LA-5 promoted organoid growth, which was demonstrated by comparing the morphological parameters (mean number and area of organoids). The profile of prostaglandins (PG), known to promote intestinal regeneration, in supernatants from organoid and fibroblast cultures were evaluated. Both PGE2 and PGD2 were detected. As compared to unstimulated controls, supernatants from the Pam3CSK4-stimulated organoids contained twice as much of PGE2 and PGD2. The changes in production of prostaglandins and the support of epithelial cell growth by myofibroblasts are factors potentially responsible for stimulatory effect of TLR2 activation. 相似文献
19.
《Veterinary microbiology》2015,175(1):17-25
To examine the effects of the NS1 and NEP genes of avian influenza viruses (AIVs) on pathogenicity in mice, we generated recombinant PR8 viruses containing 3 different NS genes of AIVs. In contrast to the reverse genetics-generated PR8 (rPR8) strain and other recombinant viruses, the recombinant virus rPR8-NS(0028), which contained the NS gene of A/chicken/KBNP-0028/2000 (H9N2) (0028), was non-pathogenic to mice. The novel single mutations of 0028 NS1 to corresponding amino acid of PR8 NS1, G139D and S151T increased the pathogenicity of rPR8-NS(0028). The replacement of the PL motifs (EPEV or RSEV) of pathogenic recombinant viruses with that of 0028 (GSEV) did not reduce the pathogenicity of the viruses. However, a recombinant virus with an EPEV-grafted 0028 NS gene was more pathogenic than rPR8-NS(0028) but less than rPR8. The lower pathogenicity of rPR8-NS(0028) might be associated with the lower virus titer and IFN-β level in the lungs of infected mice, and be attributed to G139, S151 and GSEV-PL motif of NS1 gene of 0028. In conclusion we defined new amino acid residues of NS1 related to mice pathogenicity and the presence of pathogenic NS genes among low pathogenic AIVs may encourage continuous monitoring of their mammalian pathogenicity. 相似文献
20.