云南省德宏州蚊虫分布特点及乙型脑炎病毒分离

１９８３年５月以及１９８４年和１９８９年７￣８月，在云南省德宠州路西，瑞丽和盈江三县，市捕获成年雌性蚊虫９属４４种１９０８３只。三带喙库蚊，霜背库蚊，棕头库蚊和中华按蚊是农村畜圈的主要蚊种。伪白纹伊蚊和白纹伊蚊是野外竹林区的优势蚊种。对所获蚊虫用Ｃ６／３６细胞和乳鼠方法分离病毒，结果从三带喙库蚊中分离到乙型脑炎病毒２株，从霜背库蚊，白纹伊蚊和窄翅伊蚊中各分离出１株乙型脑炎病毒。分析认为，三带喙库蚊     

逆转录聚合酶链反应检测乙型脑炎病毒核酸

本文应用逆转录聚合酶链反应（ＲＴ－ＰＣＲ）方法检测乙型脑炎病毒基历。所设计引物在Ｅ基因组，引物１位于碱基序列的第１９５３～１９７２位，引物２位于第１７８８－１８０６位。反应产物为１８５ｂｐ，内含ＨａｅⅢ限制性内切酶位点。产物在含溴化乙锭的２％琼脂糖中的电泳。本法可特异性检测乙型脑炎病毒核酸，并可检出少至５ＴＣＩＤ５０的病毒ＲＮＡ。     

从云南省宾川县蝙蝠体内分离到乙型脑炎病毒

１９９１年９月，从捕自云南省宾川县的１３２只双色帝蝙蝠和棕果蝙蝠体内分离到４株病毒。经电镜观察、血凝抑制试验和单克隆抗体免疫荧光试验证实为乙型脑炎病毒。结果表明蝙蝠在乙型脑炎病毒保存和传播中起重要作用。     

云南省洱源县流行性乙型脑炎暴发流行的病原分离与鉴定

１９９１年７￣１０月,云南省洱源县发生流行性乙型脑炎暴发流行,采用滤过性试验,免疫荧光试验,交互ＨＩ试验,交互ＣＦ试验和中和试验方法,对从该县流行期采集的病人血清分离的２株病毒和从三带喙库蚁分离到的２株病毒进行鉴定,证实４株病毒均为流行性乙型脑炎病毒,从病原学证实为流行性乙型脑炎暴发流行,同时还查明了三带喙库蚊是本次乙型脑炎流行的主要传播媒介。     

基因Ⅲ型乙型脑炎病毒Real-time PCR检测方法的建立及应用

目的建立针对云南地区流行的基因Ⅲ型乙型脑炎病毒株Real-time PCR检测方法。方法根据云南地区分离株乙型脑炎病毒株(Yunnan0901)基因组核苷酸序列设计特异性引物,构建pMD18-T-JEV-E质粒,以此为模板进行SYBR GreenⅠReal-time PCR扩增并制作标准曲线,摸索最佳反应体系条件,建立乙型脑炎病毒荧光定量PCR检测方法,并与普通RT-PCR方法相比较。结果建立的SYBR GreenⅠReal-time PCR标准曲线呈现良好的重复性和特异性,与模板浓度呈现良好的线性关系。与RT-PCR方法相比,SYBR GreenⅠReal-time PCR的灵敏度高10倍,而且不与猪瘟病毒、猪蓝耳病毒、猪圆环病毒、基孔肯雅病毒、辛德毕斯病毒核酸发生非特异性扩增,具有良好的特异性。用该方法检测云南部分地区的蚊虫样品,其中库蚊、按蚊乙型脑炎病毒阳性率分别为17.4%和30.7%,且主要为基因型Ⅲ型。结论本实验建立的检测基因Ⅲ型乙型脑炎病毒的SYBR GreenⅠReal-time PCR方法具有特异、敏感、快速、定量、重复性好等特点,可应用于乙型脑炎疫情的监测。     

基因Ⅲ型乙型脑炎病毒Real-time PCR检测方法的建立及应用北大核心CSCD

目的建立针对云南地区流行的基因Ⅲ型乙型脑炎病毒株Real-time PCR检测方法。方法根据云南地区分离株乙型脑炎病毒株(Yunnan0901)基因组核苷酸序列设计特异性引物,构建pMD18-T-JEV-E质粒,以此为模板进行SYBR GreenⅠReal-time PCR扩增并制作标准曲线,摸索最佳反应体系条件,建立乙型脑炎病毒荧光定量PCR检测方法,并与普通RT-PCR方法相比较。结果建立的SYBR GreenⅠReal-time PCR标准曲线呈现良好的重复性和特异性,与模板浓度呈现良好的线性关系。与RT-PCR方法相比,SYBR GreenⅠReal-time PCR的灵敏度高10倍,而且不与猪瘟病毒、猪蓝耳病毒、猪圆环病毒、基孔肯雅病毒、辛德毕斯病毒核酸发生非特异性扩增,具有良好的特异性。用该方法检测云南部分地区的蚊虫样品,其中库蚊、按蚊乙型脑炎病毒阳性率分别为17.4%和30.7%,且主要为基因型Ⅲ型。结论本实验建立的检测基因Ⅲ型乙型脑炎病毒的SYBR GreenⅠReal-time PCR方法具有特异、敏感、快速、定量、重复性好等特点,可应用于乙型脑炎疫情的监测。     

云南省景洪市虫媒病毒调查分析

近１０多年来，先后从云南省景洪市各乡镇的当地病人、猪、蝙蝠和蚊虫体内分离出乙型脑炎病毒２２株，从白纹伊蚊中分离到登革４型病毒１株，从蝙蝠和蚊体内分离到基孔肯雅病毒５株，从患急性期血液中分离到辛德毕斯病毒１株，从发热病人血液、脑炎病人脑脊液、猪血清和牛血清中分离到新环状病毒４７株，从黄胸鼠肺脏中检查出流行性出血热病毒抗原阳性６份；人群、猪恒河猴或鼠类血清中亦检出上述６种病毒的抗体，表明景洪市存在乙     

树Qu实验感染后血清中抗基孔肯雅病毒IgM和IgG抗体检查

成年树Ｑｕ经人工感染基孔肯雅病毒后，能产生２－６天的病毒血症。感染后第６天能产生特异性ＩｇＭ抗体，第１４－２１天为高峰，以后逐渐下降，感染后第１２天，ＩｇＧ抗体开始出现，３０－６０天为高峰，并持续不降，表明树Ｑｕ对基孔肯雅病毒敏感。     

树鼩实验感染后血清中抗基孔肯雅病毒IgM和IgG抗体检查

成年树经人工感染基孔肯雅病毒后，能产生2～6天的病毒血症。感染后第6天能产生特异性IgM抗体，第14～21天为高峰，以后逐渐下降。感染后第12天，IgG抗体开始出现，第30～60天为高峰，并持续不降，表明树对基孔肯雅病毒敏感。     

基孔肯雅病毒小鼠感染模型研究进展

基孔肯雅病毒(Chikungunya virus, CHIKV)感染引发的基孔肯雅热是一种主要经伊蚊叮咬而传播的虫媒传染病,近些年已在100多个国家流行或暴发,成为严重威胁全球公共卫生安全的虫媒病毒性传染病。CHIKV感染后可以引起急性发热、皮疹、肌肉疼痛以及慢性关节炎、腱鞘炎等临床症状,严重者可发生病毒性脑炎。小鼠模型作为CHIKV最常用的动物感染模型,在病毒感染机理、宿主抗感染免疫机制以及相关疫苗或药物研发等方面应用广泛。本文拟就国内外关于基孔肯雅病毒小鼠感染模型的最新研究进展作一综述。     

Clinical characteristics and distribution of genotypes of TT virus infection in a hepatitis C virus-hyperendemic township of a hepatitis B virus-endemic country (Taiwan)

BACKGROUND: The prevalence of TT virus (TTV) viremia, without definite clinical significance, has been reported to be higher among chronic hepatitis C patients. The status and clinical characteristics of TT virus (TTV) infection and distribution of TTV genotypes in a hepatitis C virus (HCV) hyperendemic township (Masago community) in a hepatitis B virus (HBV) endemic country (Taiwan) were investigated. METHODS: Sera from 100 Masago residents were tested for alanine aminotransferase (ALT) and markers of HBV, HCV and GB virus C/hepatitis G virus (GBV-C/HGV) and TTV-DNA. Sera of 250 blood donors as a control group were tested for TTV-DNA. Sera of Masago residents and blood donors with positive TTV-DNA were directly sequenced, and phylogenetic analyses were performed subsequently. RESULTS: The prevalences of TTV viremia in different age groups among individuals from Masago were significantly higher than that among blood donors. In regard to the subtypes of TTV, 23, seven, two, eight, one, six and one isolate were related to the genotypes 1a, 1b, 2a, 2b, 3, 4 and 5, respectively, from Masago and 21, 14, one, nine and three isolates were related to the genotypes 1a, 1b, 2a, 2b, and 4, respectively, from donors. No clinical or virological factor was associated with TTV viremia or TTV genotypes. CONCLUSIONS: TT Virus prevalence was higher among HCV hyperendemic township residents than blood donors with similar genotype distributions (genotype 1 was the most prevalent) in Taiwan. Neither TTV viremia nor a particular genotype was associated with HBV, HCV or GBV-C/HGV infection and abnormal ALT levels.     

Epidemiology of Mosquito-Borne Viruses in Egypt: A Systematic Review

There are at least five common mosquito-borne viruses (MBVs) recorded in Egypt, including dengue virus (DENV), Rift Valley fever virus (RVFV), West Nile virus (WNV), Chikungunya virus, and Sindbis virus. Unexpected outbreaks caused by MBVs reflect the deficiencies of the MBV surveillance system in Egypt. This systematic review characterized the epidemiology of MBV prevalence in Egypt. Human, animal, and vector prevalence studies on MBVs in Egypt were retrieved from Web of Science, PubMed, and Bing Scholar, and 33 eligible studies were included for further analyses. The monophyletic characterization of the RVFV and WNV strains found in Egypt, which spans about half a century, suggests that both RVFV and WNV are widely transmitted in this nation. Moreover, the seropositive rates of DENV and WNV in hosts were on the rise in recent years, and spillover events of DENV and WNV to other countries from Egypt have been recorded. The common drawback for surveillance of MBVs in Egypt is the lack of seroprevalence studies on MBVs, especially in this century. It is necessary to evaluate endemic transmission risk, establish an early warning system for MBVs, and develop a sound joint system for medical care and public health for managing MBVs in Egypt.     

各型肝炎病毒单纯及重叠感染的研究

目的 探讨病毒性肝炎患者甲～戊，庚型肝炎病毒(HAV-HEV，HGV)单纯感染及重叠感染情况。方法 采用EIA法检测病毒性肝炎患者血清抗-HAV IgM，HBV标志物、抗-HCV IgM、抗-HDV IgM、抗-HEV IgM、抗-HGV IgM。结果 共检测210例病毒性肝炎患者HAV-HEV、HGV血清标志物，20例未检出(9．5％)，190例患者检出标志物阳性(90．5％)。HBV感染率89，5％(188／210，其中有34例为既往感染，占16．2％，现症感染154例，占73．3％)；HAV感染率29．0％(61／210)，HCV、HDV感染率均为8．1％(17／210)、HEV、HGV感染率依次为10．0％(21／210)、7．1％(15／210)。各临床类型中单纯感染占61．4％(129／210)，二重感染占32．4％(68／210)，以HAV HBV、HBV HDV、HBV HEV感染模式最常见，三重感染占6．2％(13／210)，以HAV HBV HDV感染模式最常见；临床上以肝炎肝硬化、重型肝炎重叠感染常见，急性肝炎最少见。结论 病毒性肝炎中HBV感染最常见，其次为HAV感染；单纯感染、二重感染多见，三重感染少见；重叠感染发生率随病情加重而增加。     

Selection of HSV capsids for envelopment involves interaction between capsid surface components pUL31, pUL17, and pUL25

During egress from the nucleus, HSV capsids that contain DNA (termed C capsids) are preferentially enveloped at the inner nuclear membrane over capsid types lacking DNA. Using coimmunoprecipitation and biochemical analyses of wild-type and mutant capsids, we identify an interaction between a complex of pU(L)17/pU(L)25, termed the C capsid-specific complex (CCSC), and pU(L)31, a component of the nuclear egress complex (NEC). We also show that the interactions between these components are dependent on expression of all three proteins but occur independently of the pU(L)31 interacting protein and NEC component pU(L)34, as well as a kinase encoded by U(S)3 that phosphorylates both pU(L)31 and pU(L)34. The interaction between the CCSC and pU(L)31 in the NEC suggests a mechanism to conserve viral resources by promoting assembly of only those viral particles with the potential to become infectious.     

Update on the management and treatment of viral hepatitis

This review aims to summarize the current evidence on the treatment of viral hepatitis, focusing on its clinical management. Also, future treatment options and areas of potential research interest are detailed. PubMed and Scopus databases were searched for primary studies published within the last ten years. Keywords included hepatitis A virus, hepatitis B virus (HBV), hepatitis C virus, hepatitis D virus (HDV), hepatitis E virus, and treatment. Outcomes reported in the studies were summarized, tabulated, and synthesized. Significant advances in viral hepatitis treatment were accomplished, such as the advent of curative therapies for hepatitis C and the development and improvement of hepatitis A, hepatitis B, and hepatitis E vaccination. Drugs that cure hepatitis B, going beyond viral suppression, are so far unavailable; however, targeted antiviral drugs against HBV (immunomodulatory therapies and gene silencing technologies) are promising approaches to eradicating the virus. Ultimately, high vaccination coverage and large-scale test-and-treat programmes with high screening rates may eliminate viral hepatitis and mitigate their burden on health systems. The development of curative hepatitis C treatment renewed the enthusiasm for curing hepatitis B, albeit further investigation is required. Novel therapeutic options targeting HDV life cycle are currently under clinical investigation.     

A Novel Flavi-like Virus in Alfalfa (Medicago sativa L.) Crops along the Snake River Valley

Alfalfa is an important perennial forage crop in Idaho supporting dairy and cattle industries that is typically grown in the same field for as many as 4 years. Alfalfa stands of different ages were subjected to screening for viruses using high-throughput sequencing and RT-PCR. The two most common viruses found were alfalfa mosaic virus and bean leafroll virus, along with Medicago sativa amalgavirus, two alphapartitiviruses, and one deltapartitivirus. Additionally, a new flavi-like virus with an unusual genome organization was discovered, dubbed Snake River alfalfa virus (SRAV). The 11,745 nt, positive-sense (+) RNA genome of SRAV encodes a single 3835 aa polyprotein with only two identifiable conserved domains, an RNA-dependent RNA polymerase (RdRP) and a predicted serine protease. Notably, unlike all +RNA virus genomes in the similar size range, the SRAV polyprotein contained no predicted helicase domain. In the RdRP phylogeny, SRAV was placed inside the flavi-like lineage as a sister clade to a branch consisting of hepaci-, and pegiviruses. To the best of our knowledge, SRAV is the first flavi-like virus identified in a plant host. Although commonly detected in alfalfa crops in southern Idaho, SRAV sequences were also amplified from thrips feeding in alfalfa stands in the area, suggesting a possible role of Frankliniella occidentalis in virus transmission.     

河北省麻疹病毒分离结果分析

目的更好地开展麻疹病原学监测,分离麻疹病毒(MV)。方法对1994年和2003～2005年在我省分离的MV结果进行分析。结果1994年我省采集了5份咽拭子送国家麻疹实验室分离到2株MV,分别为China94-2和China94-3;2003年仅从采集的36份咽拭子中分离到1株MV;2004年和2005年采用vero-slam细胞从采集的142份咽拭子中分离到23株MV,出疹后3d内采集的合格标本分离率为20.91%(23/110),而在尿液标本和眼分泌物标本中未分离到病毒。来自不同的市采集的咽拭子标本分离比例差别较大。所有分离到的MV(26株)全部经中和试验和逆转录-聚合酶链反应鉴定,再经核苷酸序列分析鉴定均为H1基因型。结论我省已经掌握了MV的分离和鉴定技术,分离比例较高;我省多年来流行的麻疹毒株均为H1基因型,与国内流行的优势基因型一致。