山东省十地市人轮状病毒分子流行病学研究

用核酸凝胶电泳法对1985—1986年山东省十地市的318份婴幼儿急性腹泻粪便标本中测出的170份HRV阳性标本作了RNA电泳型分析,发现3个地区为HRVI亚群流行,3个地区为HRVⅡ亚群流行,4个地区为两亚群共同流行,共检出差异电泳型34个,其中14个属长RNA电泳型,20个属短RNA电泳型。在一个地区虽有多个差异电泳型毒株流行,但仅有其中的1—2个占流行优势。在两亚群毒株共同流行区,检出的差异电泳型特别多。本文并对HRV RNA电泳型多形性的原因及意义进行了讨论。     

南昌地区婴幼儿腹泻轮状病毒核酸电泳分析

应用核酸凝胶电泳法对49份婴幼儿急性腹泻粪便标本进行了分析研究。试验结果表明,其中34份呈现轮状病毒核酸电泳型。包括长型和短型两个亚群。在长型中有两种不同的电泳图型,并且对轮状病毒的实验诊断与电镜检测做了比较,结果证实二者的敏感性和特异性相似,而核酸电泳法具有更多的优点,便于推广应用。     

哈尔滨地区婴幼儿腹泻轮状病毒优势株的变化

本文对1988—1989年哈尔滨地区婴幼儿腹泻进行了轮状病毒核酸电泳型调查,并于1984—1985年资料比较,以探明这一地区轮状病毒流行优势株的变化。 标本:婴幼儿腹泻粪便标本采自哈尔滨医科大学附属二院儿科及哈尔滨红十字儿童医院。病毒RNA提取:参考Herring方法。聚丙烯酰胺电泳(PAGE):参考Uaemmli方法。 结果:123份急性婴幼儿腹泻粪便标本PAGE检测,47例呈现轮状病毒RNA图型,阳性率为38.2％。电泳图型的基本模式为4:2:3:2,表明均为A组轮状病毒。根据各片段的迁移位置差异,共可见9种不同的电泳型,其中短型3例,占6.4％,含2个电泳型;长型44例,     

成人腹泻轮状病毒的分子流行病学调查

本文在我们先前研究的基础上,报道用聚丙烯酰胺凝胶电泳技术,对我国12个地区53份成人腹泻轮状病毒(Adull Diarrhea Rotavirus, 简称 ADRV)的核酸(RNA)进行了分析。研究结果表明,我国各地流行的ADRV具有共同而独特的RNA图型,同时首次观察到不同地区的成人蝮泻轮状病毒RNA在电冰迁移率上存在着微小的差别;这意味着我国目前流行的AI)R、为一群基因图型基本相似,而在毒株间存在着微小的变异。     

不数民族新生儿及婴幼儿中人轮状病毒分子流行病学研究

用降丙烯酰胺凝胶电泳技术,对内蒙古自治区三个不同地理位置的少数民族自治旗及一个城市汉族对照区秋冬季采集的新生儿胎便及婴幼儿急性腹泻便进行轮状病毒ＲＮＡ基因组特点分析。共检测胎便标本１４６份,腹泻便标本１１６份。结果表明;几个少数民族地区流行的轮状病毒均以Ａ组Ⅱ亚组为主,并在一个地区有多种差异电泳型存在,新生儿胎便中可检出轮状病毒并显示了特征性Ａ组轮状病毒ＲＮＡ基因型。胎便中轮状病毒检出率高的地区,     

中国脊髓灰质炎Ⅰ型野毒株的PCR－RFLP法分析

近年来我国流行地区分离的脊髓灰质炎病毒多为Ⅰ型野毒。本文报导对我国一些省、自治区防疫站从急性驰缓性麻痹病人粪便中分离的７７株Ⅰ型野毒株,经ＰＣＲ－ＲＦＬＰ法分析结果,发现不同地区分离的野毒株在电泳图像上有明显差异。根据电泳图像所显示的三种酶切条带的数目,可分为１４个类型,而且同一省、自治区内不同地区（如新疆）,或同一地区不同年份（如广东）的毒株也存在着明显差异。但在某些相邻省份如广东省与海南省,９２年流行毒株电泳图像完全一致。说明本法虽不如核酸序列分析精确,但在一定程度上也能反映毒株间的差异,有助于说明流行株的亲疏关系,可用于研究毒株的分子流行病学。     

鸡传染性支气管炎病毒广西分离毒株抗原相关性的研究

本研究将26个传染性支气管炎病毒(Infectious bronchitis virus,IBV)广西分离毒株以及参考株M41和常用疫苗株H120、Ma5和4/91共30个毒株,分别与根据这些毒株S1基因高变区Ⅰ的基因分型结果而选取的属于3个不同亚群的7个代表性分离毒株和常用疫苗株H120、Ma5和4/91制备的共10个单因子血清,在鸡胚气管环培养(TOC)上进行病毒中和试验,然后根据中和试验结果对1985～2008年间课题组所分离的26个IBV广西地方流行毒株与3个常用疫苗株H120、Ma5和4/91以及参考毒株M41的抗原相关性及其血清型进行分析。结果显示,30个试验的毒株分属7个不同的血清型,其中26个分离株有两个优势血清型(占总分离株的68%),分别是血清1型(包含13个毒株)和血清2型(包含5个毒株)。此外,我们还将分离毒株的血清分型结果与重要抗原基因(包括S1、N、M和3′UTR)的分型结果之间的关系进行了比较,发现它们之间的分型结果不尽相同。研究结果表明,近年来广西存在多个血清型IBV的流行而且不同时期流行的优势血清型不同,分离毒株之间以及分离毒株与疫苗毒株之间的抗原相关性也存在着差异。     

长春地区冬季流行的轮状病毒核酸电泳型的比较

轮状病毒是婴幼儿腹泻的主要病原,在我国亦广泛流行,根据病毒基因组的电泳分析,可以研究其分子流行病学的规律。文献报道该病毒在流行区往往以一个电泳型感染为主,我们对长春地区1984～1985年和1985～1986年两个冬季流行的婴幼儿腹泻轮状病毒基因组PAGE分析的结果,也表明两个冬季都是以电泳长型感染为主,其中优势株与本室     

北京地区G1-G4型人轮状病毒地方株VP7编码基因的序列分析

本文报告了北京地区流行的４个轮状病毒地方株（Ｇ１－Ｇ４）ＶＰ７编码基因的核苷酸序列。４个地方株的该基因核苷酸全长均为１０６２ｂｐ,读码框架和已往的研究一致。地方株和相同血清型的标准株之间ＶＰ７氨基酸序列具有高度同源性（９２％－９４％）,而不同血清型间则变异较大（６９％－８０％）。不同血清型间氨基酸序列的变异主要存在于高变区内,高变区以外的区域在不同血清型轮状病毒间保守。这一序列分析结果进一步从分子水平分析了地方流行毒株的血清型别,揭示了轮状病毒地方流行毒株和标准株之间ＶＰ７序列的变异情况     

禽白血病病毒的亚群和准种多样性及其在不同选择压作用下的演变

禽白血病病毒(avian leucosis virus,ALV)是最易发生突变的病毒之一,它有多个亚群,其中感染性和致病性最强的J亚群(ALV-J)的囊膜蛋白gp85基因和LTR片段的变异性更强。ALV-J不同毒株间gp85差异很大,即使同一株病毒或同一分离物内的准种也有很大的多样性。在1988年ALV-J出现后最初的10年里,基本上只在白羽肉鸡中流行。最近10多年在我国的流行中,它又逐步适应蛋用型鸡、黄羽肉鸡及多种我国固有的地方品种鸡,而且诱发肿瘤细胞的类型也逐渐多样化,显然这与病毒的演变有关。现汇集了过去25年里国内外147个代表毒株的gp85序列及部分毒株的LTR序列,利用现代病毒分子流行病学技术,比较分析了ALV-J的准种多样性及其在不同选择压作用下的演变。以此为预测ALV进一步演变及制定更有效的预防控制措施提供新的科学数据。     

Immunological and Other Biological Characteristics of Pentons of Human Adenoviruses

Comparative hemagglutination-enhancement (HE) tests demonstrated diversified patterns of antigenic specificities both in the fiber and vertex capsomer part of pentons of human adenovirus types 3, 11 (subgroup I), 9, 15 (II), 1, 2, 4, 5, 6 (III), and 12. All fibers contained a type-specific antigen. Subgroup II and III fibers, in addition, contained specificities both unique for each subgroup and also common to the two subgroups. Fibers of serotypes 4 and 12 displayed a somewhat deviating behavior. All vertex capsomers tested shared a group-specific part. This was the only antigenic specificity demonstrable for serotype 12. Maximal penton HE titers of all sera were reached in tests with incomplete hemagglutinin of type 11. In addition, maximal HE activity of sera against individual serotypes also was recorded against pentons of other members of the same subgroup. Antigen characteristics of vertex capsomers of type 4 indicated a closer relationship to subgroup I than to subgroup III. The toxin activity of pentons was more sensitive to trypsin treatment than their capacity to function as incomplete hemagglutinin. Homotypic antipenton sera, unabsorbed or absorbed with homotypic fibers to remove antibodies against this component, and, to a varying extent, also heterotypic antipenton sera could neutralize toxin activity. Antifiber sera could neutralize toxin activity of pentons carrying short fibers (10 nm, type 3) but not of those carrying long fibers (28 to 31 nm, type 2). It is concluded that toxin activity is carried by a specific part of vertex capsomers and that cell detachment can be brought about via a direct contact between this component and cell membranes. Fiber-mediated attachment does not seem to be necessary for this biological activity to become expressed.     

Novel and Predominant Pathogen Responsible for the Enterovirus-Associated Encephalitis in Eastern China

Enteroviruses (EV) have been increasingly identified as the causative agent for unknown etiological encephalitis in many parts of the world, but the long period surveillance for enterovirus-associated encephalitis (EAE) was not reported in China. From 2002-2012 in Zhejiang, Coxsackieviruses A9, B1, B2, B3, B4, B5; and echoviruses 3, 4, 6, 9, 14, 25, 30 were detected from the unknown etiological encephalitis cases, with coxsackievirus B4 been identified here for the first time. From 2002-2004 and 2010-2012, echovirus 30 was found to be the periodically predominant serotype for in the EAE. The molecular typing results showed that all the EV isolates from this study belonged to the human EV B (HEV B) family and were distributed in three clusters.     

Mass homozygotes accumulation in the NCI-60 cancer cell lines as compared to HapMap Trios, and relation to fragile site location

Runs of homozygosity (ROH) represents extended length of homozygotes on a long genomic distance. In oncology, it is known as loss of heterozygosity (LOH) if identified exclusively in cancer cell rather than in matched control cell. Studies have identified several genomic regions which show consistent ROH in different kinds of carcinoma. To query whether this consistency can be observed on broader spectrum, both in more cancer types and in wider genomic regions, we investigated ROH patterns in the National Cancer Institute 60 cancer cell line panel (NCI-60) and HapMap Caucasian healthy trio families. Using results from Affymetrix 500 K SNP arrays, we report a genome wide significant association of ROH regions between the NCI-60 and HapMap samples, with much a higher level of ROH (11 fold) in the cancer cell lines. Analysis shows that more severe ROH found in cancer cells appears to be the extension of existing ROH in healthy state. In the HapMap trios, the adult subgroup had a slightly but significantly higher level (1.02 fold) of ROH than did the young subgroup. For several ROH regions we observed the co-occurrence of fragile sites (FRAs). However, FRA on the genome wide level does not show a clear relationship with ROH regions.     

The study of reinnervation of gastric vagus nerves after lesser curvature and fundus myotomy in cats

The aim of this study was to investigate the reinnervation of gastric vagus nerves after lesser curvature and fundus myotomy (LCFM) in cats. After injection of the retrogradely tracing agent horseradish peroxidase (HRP) into the stomach wall along the predicted line of LCFM, the neuronal cell bodies of the afferent and efferent fibers were well-defined in both the nodose ganglia (NG) and dorsal motor nucleus of the vagus nerve (DMNx), respectively. The animals were divided into three subgroups. After LCFM, at intervals of 0 day, 2, 4, 6, 8, 10 and 12 weeks, respectively, they were processed for a HRP histochemical study in both subgroups A and B. In subgroup A, HRP was directly injected into both sides of the stomach wall distal to the dissecting plane of LCFM. A further corpoantral circumferential myotomy (CACM) was performed in subgroup B to eliminate the possibility of collateral sprouting via antropyloric vagus innervation before applying HRP to the same sites as those of subgroup A. Both LCFM and CACM with an overlapping suture were performed in subgroup C, and HRP was then injected into sites similar to those of subgroup A on the twelfth postoperative week. HRP-labeled cells were found in the NG on the sixth week and in the DMNx on the eighth week in subgroups A and B. The labeled cells increased in number until the twelfth week in both subgroups A and B. However, cells found in subgroup A were always more numerous than those found in subgroup B in both the NG and DMNx at equivalent time intervals. No labeled cell was found in the NG or DMNx in subgroup C during the 12 week study period.(ABSTRACT TRUNCATED AT 250 WORDS)     

Heterogeneity of koala retrovirus isolates

Koala retrovirus (KoRV) is a gammaretrovirus which may induce immune suppression, leukemia and lymphoma in koalas. Currently three KoRV subgroups (A, B, and J) have been reported. Our phylogenetic analysis suggests that KoRV-B and KoRV-J should be classified as the same subgroup. In long terminal repeat (LTR), a KoRV-B isolate has four 17 bp tandem repeats named direct repeat (DR)-1, while a KoRV-J isolate (strain OJ-4) has three 37 bp tandem repeats named DR-2. We also found that the promoter activity of the KoRV-J strain OJ-4 is stronger than that of original KoRV-A, suggesting that KoRV-J may replicate more efficiently than KoRV-A.     

Molecular evolution and circulation patterns of human respiratory syncytial virus subgroup a: positively selected sites in the attachment g glycoprotein

Human respiratory syncytial virus (HRSV) is the most common etiological agent of acute lower respiratory tract disease in infants and can cause repeated infections throughout life. In this study, we have analyzed nucleotide sequences encompassing 629 bp at the carboxy terminus of the G glycoprotein gene for HRSV subgroup A strains isolated over 47 years, including 112 Belgian strains isolated over 19 consecutive years (1984 to 2002). By using a maximum likelihood method, we have tested the presence of diversifying selection and identified 13 positively selected sites with a posterior probability above 0.5. The sites under positive selection correspond to sites of O glycosylation or to amino acids that were previously described as monoclonal antibody-induced in vitro escape mutants. Our findings suggest that the evolution of subgroup A HRSV G glycoprotein is driven by immune pressure operating in certain codon positions located mainly in the second hypervariable region of the ectodomain. Phylogenetic analysis revealed the prolonged cocirculation of two subgroup A lineages among the Belgian population and the possible extinction of three other lineages. The evolutionary rate of HRSV subgroup A isolates was estimated to be 1.83 x 10(-3) nucleotide substitutions/site/year, projecting the most recent common ancestor back to the early 1940s.     

Tropical spastic paraparesis/HTLV-I associated myelopathy

In 1985 we had the first indication that human T-cell lymphotropic virus (HTLV-I) was the possible etiological agent of a chronic myelopathy that seemed to be peculiar to the tropics and that is now known as endemic tropical spastic paraparesis (TSP). IgG antibodies to HTLV-I were found in serum and cerebrospinal fluid of patients from Jamaica, Colombia, Martinique, and shortly after in southern Japan, where the disease is called HTLV-I-associated myelopathy (HAM). The HTLV-I seropositivity was first determined by enzyme-linked immunoassay and confirmed by western immunoblot and in the cerebrospinal fluid specific IgG oligoclonal bands to HTLV-I were found in cerebrospinal fluid and not in serum. These laboratory findings indicated that HTLV-I could be neuropathogenic and for the first time a single etiological agent was identified in patients from different countries. Thus, in less than a decade a century of research and speculation was seemingly resolved when this disease, which was thought to occur only in blacks of poor socieconomic status in tropical countries, was shown to occur in all ethnic groups of varying socioeconomic status in temperate, subtropical, and tropical climates.     

Occurrence and phylogenetic analysis of bovine respiratory syncytial virus in outbreaks of respiratory disease in Norway

Background

Bovine respiratory syncytial virus (BRSV) is one of the major pathogens involved in the bovine respiratory disease (BRD) complex. The seroprevalence to BRSV in Norwegian cattle herds is high, but its role in epidemics of respiratory disease is unclear. The aims of the study were to investigate the etiological role of BRSV and other respiratory viruses in epidemics of BRD and to perform phylogenetic analysis of Norwegian BRSV strains.

Results

BRSV infection was detected either serologically and/or virologically in 18 (86%) of 21 outbreaks and in most cases as a single viral agent. When serology indicated that bovine coronavirus and/or bovine parainfluenza virus 3 were present, the number of BRSV positive animals in the herd was always higher, supporting the view of BRSV as the main pathogen. Sequencing of the G gene of BRSV positive samples showed that the current circulating Norwegian BRSVs belong to genetic subgroup II, along with other North European isolates. One isolate from an outbreak in Norway in 1976 was also investigated. This strain formed a separate branch in subgroup II, clearly different from the current Scandinavian sequences. The currently circulating BRSV could be divided into two different strains that were present in the same geographical area at the same time. The sequence variations between the two strains were in an antigenic important part of the G protein.

Conclusion

The results demonstrated that BRSV is the most important etiological agent of epidemics of BRD in Norway and that it often acts as the only viral agent. The phylogenetic analysis of the Norwegian strains of BRSV and several previously published isolates supported the theory of geographical and temporal clustering of BRSV.