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1.
目的 了解几年流感病毒在深圳地区活动的特点及甲3(H3N2)亚型毒株HA1基因演变概况。方法 病毒分离采用常规的鸡胚双腔接种,毒株检和常量半加敏HI测定。新鲜收获含病毒粒的鸡胚尿囊液用来提取RNA,经逆转录合成cDNA,经聚合酶链反应(PCR)扩增,产物纯化采用双脱氧链末端终止法进行核苷酸序列测定。结果 近几年来深圳地区流感活动概况与全国情况相一致;在人群中仍同时流行H3N2,H1N1 型和乙型毒  相似文献   

2.
目的 了解近几年流感病毒在深圳地区活动的特点及甲3(H3N2) 亚型毒株HA1 基因演变概况。方法 病毒分离采用常规的鸡胚双腔接种,毒株检定用常量半加敏HI测定。新鲜收获含病毒粒的鸡胚尿囊液用来提取RNA,经逆转录合成cDNA,经聚合酶链反应(PCR) 扩增,产物纯化,采用双脱氧链末端终止法进行核苷酸序列测定。结果 近几年来深圳地区流感活动概况与全国情况相一致:在人群中仍同时流行H3N2,H1N1 亚型和乙型毒株,当甲型毒株活动减弱时,乙型毒株活动就增强,反之,甲型毒株增强时,乙型毒株就减弱。随着时间的推移,H3N2 亚型毒株HA1 基因不断地发生点突变,这种突变严重受人群免疫压力所影响,1996 年的毒株与1995 的毒株相比,不仅氨基酸替换点中多数是位于抗原决定簇区或受体结合部位上,并增加两个糖基化位点,故导致H3N2 毒株於1996 年活动明显增强。结论 近来在深圳地区人群中仍同时流行着H3N2,H1N1 亚型和乙型流感病毒。然而,不同年其优势毒株是不一样的。1996 年H3N2 毒株活动增强是由于其HA1 区氨基酸序列发生替换所造成。  相似文献   

3.
禽H9N2亚型流感病毒能感染人的发现   总被引:141,自引:10,他引:131  
目的了解禽(H9N2)亚型流感病毒是否能感染人。方法对人、鸡和猪进行H9亚型毒株血清流行病学调查。对流感样患者和鸡咽喉部采样,用常规鸡胚双腔法分离流感病毒并进行毒株鉴定。对分离出H9N2亚型毒株的患者进行个案调查。结果约19%的人含有对H9N2毒株的抗体,其HI滴度为≥20,从流感样患者中分离到5株H9N2病毒。结论H9N2亚型毒株能自然感染人。  相似文献   

4.
1996年1月太原铁路卫生防疫站从上感患者中分离到3株流感病毒。经血清学鉴定,它们不同于1989和1992年所发现的H1N2亚型毒株,其HA的抗原性类似于A/PR/8/34(H1N1)病毒,而明显不同于当前人群中流行的H1N1亚型毒株。病毒粒不同基因节段迁移率比较表明,它们的1~4基因节段迁移率接近于A/PR/8/34(H1N1)毒株,5~6基因节段迁移率类似于A/武汉/359/95(H3N2)病毒,而7~8两节段既不同于A/PR/8/34(H1N1),又不同于A/武汉/359/95(H3N2)病毒。故可认为它们是一种新重配的H1N2亚型毒株。  相似文献   

5.
流感病毒A/Guangdong/28/94HA1基因序列分析   总被引:4,自引:0,他引:4  
自1968年流感病毒HaN2亚型首次引起人类暴发流行以来,该亚型病毒在人群中一直传播。我们在血清学抗原分析的基础上,采用RT-PCR测序方法,对1994年广东地区的流行毒株A/Guangdong/28/94HA1基因序列进行分析,了解其核苷酸的变异程度。材料与方法1.流感毒株:A/Guangdong/28/94,由广东省卫生防疫站分离,并鉴定为甲型流感病毒H3N2亚型。毒株接种于鸡胚尿囊腔增殖,收获鸡胚尿囊液后,超速离心,并用30%~60%的蔗糖梯度离心纯化。2.提取病毒RNA:RNAzolTM…  相似文献   

6.
目的 研究新分离到的H1N2亚型毒株血凝素(HA)和神经氨酸酶(NA)基因的来源。方法 病毒通过鸡胚增殖后提取其RNA,通过逆转录合成cDNA,经PCR扩增和产物纯化,用双脱氧链终止法进行核苷酸序列测定,并用MegAlign(1.03版)和Editseq(3.69版)软件进行种系发生学分析。结果 新分离到H1N2毒株HA1区氨基酸序列与A/PR/8/34(H1N1)和A/Guamgdong/6/9  相似文献   

7.
H1N2新亚型流感病毒神经氨酸酶基因来源的进一步研究   总被引:1,自引:0,他引:1  
对流感病毒H1N2亚型重组株A/哈防/1/88、A/哈防/12/92以及H3N2亚型病毒株A/雅防/2/87、A/京防/57/898和A/粤防/1/92神经氨酸酶(NA)基因核苷酸全序列的测定,进一步弄清了A/哈防/1/88病毒株的NA基因确来自当时人群中流行的H3N2亚型病毒株,很可能是来自A/雅防/2/87类病毒株;而A/哈防/12/92病毒株的NA基因可能是与A/哈防/1/88病毒株的NA基  相似文献   

8.
从我国人群中再次分离到H9N2亚型流感病毒   总被引:28,自引:2,他引:26  
目的 了解分离流感病毒毒株表面抗原亚型和特性及其来源。方法 病毒通过MDCK细胞分离,用红细胞凝集抑制(HI)和神经氨酸酶抑制(NI)测定对病毒株表面抗原进行鉴定和特性分析,人血清中抗体测定采用HI和中和实验。对患者进行个」案调查。结果 分离物为甲型流感病毒H9N2亚型,属G9类似毒株,它的HA抗原特性与已经从人、鸡和鸽分离到的H9N2亚型毒株均有差异。患者恢复期血清对分离物的HI抗体滴度为400  相似文献   

9.
人与猪群中H3N2亚型流感病毒间关系的研究   总被引:2,自引:0,他引:2  
通过血清流行病学调查、毒粒HA1基因核苷酸序列分析和HA1蛋白氨基酸序列比较,证实了人与猪H3N2亚型毒株间存在着极为密切的关系,即H3N2亚型毒株新变种在人群中出现后,很快在猪群中就能找到它存在的依据。同时猪群中H3N2亚型毒株抗体阳性率高低反映出了人群中H3N2病毒活动程度的强弱。这些结果说明,猪可能在人流感疾病发生、流行和大流行株起源中起着重要的作用。同时猪群中流感病毒抗体阳性率可做为判断人群中流感活动程度的一个指标。  相似文献   

10.
目的 明确广东鹅流感病毒296H5 N1 亚型毒株RNA13 和RNA5 节段核苷酸全序列及其所编码蛋白的氨基酸序列,以及这些基因节段与香港禽流感病毒15697H5 N1 亚型毒株相应节段间的关系。方法 病毒粒RNA经逆转录合成cDNA,经聚合酶链反应(PCR) 扩增,产物纯化,采用双脱氧链末端终止法进行核苷酸序列测定。结果 广东鹅流感病毒296H5 N1 亚型毒株RNA13 和RNA5 节段长度分别为2341,2 341 ,2 233 和1565 个核苷酸。它们分别编码PB2( 含759 个氨基酸),PB1( 含757个氨基酸) ,PA( 含716 个氨基酸) 和NP蛋白( 含498 个核苷酸) 。这些蛋白与香港禽流感病毒15697H5 N1 亚型毒株相应蛋白氨基酸序列的同源性分别为96-4% ,97-2% ,97-3 % 和97-0% 。结论 本毒株RNA13 和RNA5 节段长度分别为2 341,2 341,2 233 和1 565 个核苷酸,它们与香港15697H5 N1 亚型毒株间存在着差异  相似文献   

11.
12.
Myristylation is one of several post-translational modifications that occur on vaccinia virus (VV) proteins. Previously, time course labeling of VV-infected cells with myristic acid had indicated that five late proteins (17, 25, 36, 38 and 92 kDa) are myristylated. Four of these proteins were mapped to the E7R, L1R, AI6L and G9R open-reading frames, respectively, because of the predicted presence of the N-myristyltransferase recognition sequence (M-G-X-X-X-S/T/A) at their amino termini. In contrast, computer analyses of large (80–100 kDa) VV open reading frames did not reveal any predicted species with this N-terminal motif. By immunoprecipitation with monospecific sera and transient expression of cloned gene products, the myristylated 92-kDa protein has been demonstrated to be the A-type inclusion protein encoded by the Western Reserve (WR) strain of VV. Labeling of cowpox virus (CPV) infected cells with myristic acid indicated that the 160-kDa A-type inclusion protein appears to be myristylated as well. Both the VV 92-kDa and the CPV 160-kDa A-type inclusion proteins labeled with myristic acid were stable to hydroxylamine treatment, suggesting an amide linkage between the fatty acid and the acceptor protein. HPLC analysis confirmed that the 92-kDa protein was in fact myristylated. This data suggests that poxvirus ATI proteins may be subject to a novel type of internal myristylation modification, and the roles such modifications may play in the replication cycles of these viruses is discussed.  相似文献   

13.
Five patients with acute hepatitis B and four with fulminant hepatitis B were selected for sequencing of the precore/core gene of the virus strains. Furthermore, identical sequencing was done with the HBV of the infectious sources, i.e., the sexual partner in eight cases and a natural child (chronic carrier) infecting the mother in one case. Of the subjects responsible for the infection, four were healthy HBV carriers, three suffered from chronic hepatitis B, and one from acute and one from fulminant hepatitis B. The nucleotide sequences of HBV from both the patients and the implicated sources of infection exhibited perfect identity of the precore region and perfect or high identity of the core region. The completely or nearly identical strain of virus seemed to proliferate successively in the patients following the transmission from the infecting individuals regardless of sequence variations and infectious status. In two cases a peculiar pattern of infection and disease was found: In one married couple the husband, during the incubation period of acute hepatitis B, infected his wife, who developed fulminant hepatitis. In another married couple, both partners ultimately developed fulminant hepatitis (the wife being the source of the infection). © 1994 Wiiey-Liss, Inc.  相似文献   

14.
This study aims to assess the incidence rate of Pteropine orthreovirus (PRV) infection in patients with acute upper respiratory tract infection (URTI) in a suburban setting in Malaysia, where bats are known to be present in the neighborhood. Using molecular detection of PRVs directly from oropharyngeal swabs, our study demonstrates that PRV is among one of the common causative agents of acute URTI with cough and sore throat as the commonest presenting clinical features. Phylogenetic analysis on partial major outer and inner capsid proteins shows that these PRV strains are closely related to Melaka and Kampar viruses previously isolated in Malaysia. Further study is required to determine the public health significance of PRV infection in Southeast Asia, especially in cases where co‐infection with other pathogens may potentially lead to different clinical outcomes. J. Med. Virol. 87:2149–2153, 2015. © 2015 Wiley Periodicals, Inc.
  相似文献   

15.
Organization of orthopoxvirus proteins of the kelch superfamily and their genes were analyzed and compared. Complete genomic sequences of variola (VAR), monkeypox (MPV), vaccinia (VAC), and species-specific regions of cowpox (CPV) viruses were used in the work. Despite the multiplicity of kelch-like proteins in orthopoxviruses, their function is still vague. It has been discovered that the genes of orthopoxvirus kelch-like proteins are localized only to the terminal variable regions of the genome and display species-specific differences in the lengths of the proteins they potentially encode. All the genes belonging to kelch superfamily in the genome of VAR, which has the only host–the man, are mutationally destroyed. However, CPV, displaying the widest host range among orthopoxviruses, encode the most numerous set of kelch-like proteins. Weak homologies between kelch-like proteins of one virus were demonstrated as well as high homologies between isologues of different orthopoxvirus species. The comparison performed suggest that CPV virus is most ancient and may be considered as the ancestor of other orthopoxviruses pathogenic for humans.  相似文献   

16.
目的 了解庚型肝炎病毒(HGV)感染在广西柳州地区不同人群中的感染状况,并比较静脉毒瘾者与健康体检者HGV,乙型肝炎病毒(HBV)、丙型肝炎病毒(HCV)与HGV共同感染的特点,方法 应用酶联免疫法(ELA)检测抗-HGV,抗-HCV,HBVM(HBsAg,HBsAb,HBeAg,HBeAb,HBcAb),并对抗-HGV阳性者随机抽取20例(19%)进一步用逆转录套式PCR(PT-nPCR)法检测  相似文献   

17.
Arboviruses with neuroinvasive potential are gaining more attention due to the increased number of cases of autochthonous and imported infections in the human host. Diagnosis of infection caused by these viruses in patients with central nervous system (CNS) diseases is still underestimated and these infections represent an emerging threat to public health. We describe a model suitable for the laboratory surveillance of neuro-arbovirosis that was applied in the Emilia-Romagna region, north-eastern Italy, during the 2012 summer season. One hundred and twenty cases of suspected neuroinvasive infection were tested for arboviral agents on the basis of clinical and laboratory signs and epidemiological data. The most common virus detected was Toscana virus (TOSV): anti-TOSV specific antibodies or viral components were detected in 28.3% of the cases; 79.4% of the TOSV cases were in the acute phase of infection. No cases resulted in acute phase for West Nile (WNV), Usutu (USUV), Chikungunya (CHIKV) or Dengue (DENV) virus infection. Conversely, two patients with a history of staying in a tick-borne encephalitis virus (TBEV) endemic area showed a probable TBEV infection. These results emphasize the importance of a complete and →ready to act‘ laboratory diagnostic system to be implemented within the larger frame of a regional integrated surveillance system.  相似文献   

18.
The complete RNA1 sequences of two isolates (fungus transmissible and non-fungus transmissible) of barley mild mosaic virus (BaMMV) were obtained. The two isolates' RNA1 sequences had very high sequence identity (99.3%), and of the 15 amino acid differences (out of 2258) between the putative polyproteins, 11 were conservative and unlikely to affect the structure or function of the protein. The remaining amino acid differences were thought unlikely to affect fungus transmission because they occur in the CI- and NIb-coding regions. This strongly suggests that the P73 protein of RNA2 (which has a 364-aa deletion in the non-fungus-transmissible isolate) is involved in fungus transmission of BaMMV.  相似文献   

19.
In order to investigate whether Puumala virus (PUUV) or PUUV-like virus is present in China, Clethrionomys rufocanus and C. rutilus were captured in the Jilin province during the spring and autumn of 2002-2003 for detection of PUUV viral RNA by RT-PCR and confirmation of PUUV-positive antigens by an immunofluorescence assay. PUUV-positive RNA was identified in six out of 121 C. rufocanus but not in any of the 41 C. rutilus. Complete S and partial M sequences (nt 1,316-1,598 and 2,687-3,089) were amplified by RT-PCR directly from some of the antigen positive lung tissues and subjected to nucleic acid sequencing. It was found that the Chinese PUUV-like viruses were related most closely with the PUUV strains with 77.7-81.7% identity at the nucleotide level and 91.7-97% identity at the amino acid level for S segment, and with 77-78.8% identity at the nucleotide level and 91.5-92.6% identity at the amino acid level for the partial M segment (nt 1,316-1,598). Genetic analysis indicated that the Chinese PUUV-like viruses shared the highest level of identity with the viruses which circulate in C. rufocanus in the Far East region of Russia with 85.1-87.4% identity at the nucleotide level and 95.9% identity at the amino acid level for the partial M segment (nt 2,687-3,089), respectively. Phylogenetic analysis revealed that the Chinese PUUV-like viruses are distinct from those identified from Japan, South Korea, Europe or Russia. These results indicate that PUUV-like virus is present in China in addition to Hantaan, Seoul and Dabieshan viruses.  相似文献   

20.
Hepatitis, a significant cause of mortality worldwide, results in around 1.34 million deaths each year globally. Africa is not exempt from the plague of Hepatitis. Around 100 million estimated individuals are infected with Hepatitis B or C. Egypt has the highest prevalence of cases of Hepatitis followed by Cameroon and Burundi. The continent is severely affected by the onset of the COVID-19 pandemic, as the virus has added an additional burden on the already fragile continent. With the pandemic, it is presumable that Hepatitis like other viral diseases will pose a threat to collapsing healthcare system. Therefore, for Africa to become more resilient in the face of such menaces, including Hepatitis, further prevention policies are required to be implemented  相似文献   

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