成人巨细胞病毒性肝炎42例临床分析

巨细胞病毒(Cytomeglovirus,CMY)属于疱疹病毒β亚科,在人群中感染率相当高[1]。由于CMV的毒力较弱,多数表现为隐性或轻症感染,当免疫功能低下时,常导致严重感染。有关成人CMV肝炎的报道尚少[1-5],现将我院收治的42例CMV肝炎报告如下。     

幽门螺杆菌的毒力研究与分型

幽门螺杆菌(Helicobacter pylori,Hp)是一种生长在胃粘膜表面与粘膜层之间的微需氧菌.自1983年Marshall et al首次从胃粘膜中分离出Hp以来,大量研究表明该菌与慢性胃炎[1]、消化性溃疡密切相关,也与胃癌有一定关系.但人群中Hp感染率为50%左右,而只有少数Hp感染者发展为消化性溃疡甚至胃癌,造成这种反应的差异有两个原因,一是Hp毒力的大小,二是人体的防御能力.而Hp的毒力又依Hp亚型不同而不同,故各地区感染Hp的结果也不一样.因此,对Hp毒力的研究受到重视.     

狂犬病两株不同毒力克隆株病毒的神经毒力和全长基因序列比较

目的 对2株毒力不同的狂犬病病毒克隆株(CTN181-3和CTN181-12)进行神经毒力和全长基因序列的比较。方法 分别对2株病毒用10、14和21日龄小鼠脑内接种,测定小鼠的致死力(LD₅₀);同时用空斑法测定2株病毒的病毒滴度(PFU),以lgPFU/lgLD₅₀比较2株病毒的毒力差异;分别对2株病毒进行全基因序列测定并分析,找出毒力差异关键基因位点。结果 2株病毒对10、14和21日龄小鼠的lgPFU/lgLD₅₀,CTN181-3株为0.07、3.40和6.60,CTN181-12株为<-0.9、<-0.6和1.04。全基因序列分析表明,二者共有8个核苷酸和6个位点的氨基酸存在差异。结论 CTN181-3株的神经毒力明显低于CTN181-12株,两者间6个氨基酸的差异是其毒力差异的分子基础。     

狂犬病固定毒Vero细胞适应株3aG-V的生物学特性研究

对狂犬病固定毒Vero细胞适应株 3aG V的生物学特性进行了研究 ,包括病毒的形态、抗原结构、培养条件、致病性、免疫原性、纯毒试验及其在中枢神经系统是否形成尼氏小体检查。结果表明狂犬病病毒 3aG V株具有抗原性好 ,培养产毒量高 ,保持有aG固定株弱毒性、传代稳定、无变异 ,可作为替代地鼠肾细胞狂犬病疫苗aG毒株 ,用于Vero细胞培养病毒生产出毒液毒力高 ,灭活后效力高 ,安全性好的纯化Vero细胞狂犬病疫苗的生产用疫苗株。     

中国人类免疫缺陷病毒-1感染者细胞毒性T淋巴细胞特异性应答

目的 探讨中国人类免疫缺陷病毒（HIV）／艾滋病（AIDS）患者HIV特异性细胞毒性T淋巴细胞（CTL）应答的特征。方法 以HIV-1 B、C亚型构建的2个全基因组肽库作为抗原，通过酶联免疫斑点（ELISPOT）法检测HIV／AIDS患者HIV特异性CTL应答。结果 无论HIV-1 B亚型还是HIV-1 C亚型所构建肽库的应答效应和频率主要集中在Gag和Nef蛋白，其他蛋白也有不同程度的应答。HIV-1 B、C亚型间应答比较，整体范围大致相同，但单个肽段水平还存在着一定差异，B亚型应答频率最高的是Nef的GPKEPFRDYVDRFYKTLR（5／17，29．4％）和Gag的LWVYHTQGYFPDWQNY（5/17，29．4％），C亚型应答频率最高的是Gag的GPKEPFRDYVDRFFKTLR应答频率为35．29％。结论 中国人群CTL应答多集中在Gag和Nef蛋白，B、C亚型在单个肽段水平略有差异。提示中国人群的CTL应答研究对设计针对中国人群的HIV疫苗有较重要的意义。     

地方株肾综合征出血热病毒生物学特性研究

肾综合征出血热(HFRS)分为4个血清型,目前国内已证实存在Hantaan型(HTN),Seoul(SEO)2个血清型.根据单克隆抗体的抗原分析认为,出血热病毒有复杂的抗原决定簇,毒株间存在明显的抗原差异.我们选择肾综合征出血热疫区抗原阳性鼠肺组织,现症病人外周静脉血及尿液,分离出11株出血热病毒.用McAb对其抗原性进行分析,同时测定毒株毒力.     

人类免疫缺陷病毒和丙型肝炎病毒重叠感染者的临床及免疫特征

目的 观察人类免疫缺陷病毒(HIV)和HCV重叠感染者与慢性丙型肝炎患者临床特征及HCV特异性细胞毒性T淋巴细胞(CTL)的数量及功能,探讨两组患者免疫功能的差异及其可能的影响因素.方法 以HIV和HCV重叠感染患者59例、慢性丙型肝炎患者36例为研究对象,取治疗前外周血检测肝脏生物化学指标、血常规、外周血T淋巴细胞亚群(CD4+T、CD8+T淋巴细胞计数)及HIV、HCV病毒载量,以酶联免疫斑点法检测HCV特异性CTL的数量和功能,统计学分析两组问免疫功能的差异及与上述检测指标的相关性. 结果 中国河南省有偿献血、单采血浆人群HIV感染者中HIV和HCV重叠感染率达60.8%.ALT、AST值在重叠感染组与HCV组间差异无统计学意义;球蛋白在重叠感染组为(40.3±5.8)g/L,HCV组为(32.8±6.3)g/L,差异有统计学意义(P＜0.01).重叠感染组外周血CD4+T淋巴细胞数明显低于HCV组(P＜0.01),而CD8+T淋巴细胞数高于HCV组(P＜0.01).重叠感染组HCV RNA定量高于HCV组(P＜0.01).重叠感染组对HCV-NS3区肽段的反应强度(每106个外周血单个核淋巴细胞中斑点形成细胞的个数)较HCV组弱,649.34±685.90对比1233.70±1085.16,差异有统计学意义(P＜0.05).重叠感染组白蛋白与HCV病毒载量呈现负相关(r=0.540);重叠感染组对HCV-NS3区肽段反应强度与HIV病毒载量负相关(r=0.356);重叠感染患者CD4+T淋巴细胞数与血小板正相关(P＜0.05).但未见重叠感染组HCV RNA与CD4+T淋巴细胞数量及HIVRNA水平有相关关系.结论 重叠HIV感染有利于HCV的复制,而HIV载量可影响针对HCV的特异性免疫反应,HIV载量高则不利于HCV的清除.慢性丙型肝炎患者重叠HIV感染时,病情易慢性化,预后更差.     

一名HIV/TB双重感染者的HIV分离和鉴定

1996年8月,我们采用改良的正常人PBMCs与病人PBMCs共培养法,从一名HIV/TB双重感染者的PBMCs中分离出1株HIV—1病毒,命名为GD—3.该毒株毒力强,在正常人PBMCs中培养能引起明显的细胞病变,其HIV—1p24抗原滴度超过阈值,但对H_9细胞不敏感.该毒株经基因序列分析为HIV-1E亚型,与广东省其它经性途径感染HIV人群中的HIV-1亚型相同.     

肠道病毒D68感染致急性弛缓性脊髓炎的研究进展

自2014年肠道病毒D68感染在北美地区暴发流行以来,其已成为全球范围内导致急性弛缓性脊髓炎(acute flaccid myelitis,AFM)的主要病原体之一。肠道病毒D68在人群中持续流行并累积变异,可进化出嗜神经系统的高毒力致病株。目前尚无有效的疫苗和抗病毒药物,故对病毒致病机制的研究尤显重要。本研究主要从肠...     

HIV/AIDS病人CD+4T淋巴细胞Th1型与Th2型变异分析

目的 研究艾滋病(AIDS)病人、艾滋病病毒(HIV)感染者、健康人群的Th1/Th2淋巴细胞亚群平衡漂移.方法 胞外CD分子染色和胞内细胞因子染色相结合,应用流式细胞术分析CD 4T淋巴细胞的Th1/Th2亚群百分比.结果 3组人群在CD 4T淋巴细胞计数、Th1细胞百分比、Th2细胞百分比3个指标的分布上,均表现出显著性差异(P＜0.001).正常人群和HIV/AIDS病人在Th1和Th2细胞百分比分布上,均未表现出显著性差异(P＝0.067,P＝0.835).艾滋病病人Th1型细胞百分比的均值在治疗过程中呈阶梯状上升趋势,其与治疗时间在68周内的回归系数为0.741,但无统计学意义(r＝0.741,P＝0.057);Th2细胞百分比的均值在治疗过程中呈明显的下降趋势,其与治疗时间在68周内的回归系数为0.847,有统计学意义(r＝0.847,P＝0.016).结论 监测CD 4T淋巴细胞Th1/Th2亚群漂移,对于了解艾滋病病人免疫功能变化,认识艾滋病发展规律有重要意义.     

Molecular evolution of hepatitis A virus in a human diploid cell line

AIM: To investigate the hotspots, direction, and the time course of evolution of hepatitis A virus in the process of consecutive cell culture passage in human KMB17 diploid cells. METHODS: Wild type hepatitis A virus H2w was serially propagated in KMB17 cells until passage 30, and the full-length genomes of H2w and its six chosen progenies were determined by directly sequencing RT-PCR products amplified from viral genomic RNA. Alignment comparison of sequences from H2w with its six progenies and phylogenetic analysis of the whole VP1 region from H2w, progenies of H2w, and other cell culture adapted hepatitis A virus were then carried out to obtain data on the molecular evolution of hepatitis A virus in the process of consecutive passage in KMB17 cells. RESULTS: Most of the mutations occurred by passage 5 and several hotspots related to adaptation of the virus during cell growth were observed. After that stage, few additional mutations occurred through the remaining duration of passage in KMB17 cells except for mutation in the virulence determinants, which occurred in the vicinity of passage 15. The phylogenetic analysis of the whole VP1 region suggested that the progenies of H2w evolved closely to other cell culture adapted hepatitis A virus, i.e. MBB, L-A-1, other than its progenitor H2w. CONCLUSION: Hepatitis A virus served as a useful model for studying molecular evolution of viruses in a given environment. The information obtained in this study may provide assistance in cultivating the next generation of a seed virus for live hepatitis A vaccine production.     

庚型肝炎病毒感染对重型肝炎发病的影响

目的探讨庚型肝炎病毒(HGV)感染在重型肝炎发病中的作用. 方法采用RT-PCR及EIA法检测重型肝炎患者血清HGV RNA及抗-HGV阳性情况,并与临床肝功能、病死率进行比较. 结果各临床类型重型肝炎HGV感染率差异无显著性(χ2=2.54, P＞0.05),HGV感染病例ALT升高较低,间接胆红素(SBil)较高、A/G比值较低,病死率显著低于HGV(-)病例(χ2=4.68,0.01＜P＜0.05),单纯HGV感染少见. 结论庚型肝炎病毒感染不加重肝衰竭.     

Ecological association between HIV and concurrency point-prevalence in South Africa's ethnic groups

HIV prevalence between different ethnic groups within South Africa exhibits considerable variation. Numerous authors believe that elevated sexual partner concurrency rates are important in the spread of HIV. Few studies have, however, investigated if differential concurrency rates could explain differential HIV spread within ethnic groups in South Africa. This ecological analysis, explores how much of the variation in HIV prevalence by ethnic group is explained by differential concurrency rates. Using a nationally representative survey (the South African National HIV Prevalence, HIV Incidence, Behaviour and Communication Survey, 2005) the HIV prevalence in each of eight major ethnic groups was calculated. Linear regression analysis was used to assess the association between an ethnic group's HIV prevalence and the point-prevalence of concurrency. Results showed that HIV prevalence rates varied considerably between South Africa's ethnic groups. This applied to both different racial groups and to different ethnic groups within the black group. The point-prevalence of concurrency by ethnic group was strongly associated with HIV prevalence (R² = 0.83; p = 0.001). Tackling the key drivers of high HIV transmission in this population may benefit from more emphasis on partner reduction interventions.     

In Vitro and In Vivo Characterization of a Pigeon Paramyxovirus Type 1 Isolated from Domestic Pigeons in Victoria,Australia 2011

Significant mortalities of racing pigeons occurred in Australia in late 2011 associated with a pigeon paramyxovirus serotype 1 (PPMV-1) infection. The causative agent, designated APMV-1/pigeon/Australia/3/2011 (P/Aus/3/11), was isolated from diagnostic specimens in specific pathogen free (SPF) embryonated eggs and was identified by a Newcastle Disease virus (NDV)-specific RT-PCR and haemagglutination inhibition (HI) test using reference polyclonal antiserum specific for NDV. The P/Aus/3/11 strain was further classified as PPMV-1 using the HI test and monoclonal antibody 617/161 by HI and phylogenetic analysis of the fusion gene sequence. The isolate P/Aus/3/11 had a slow haemagglutin-elution rate and was inactivated within 45 min at 56 °C. Cross HI tests generated an R value of 0.25, indicating a significant antigenic difference between P/Aus/3/11 and NDV V4 isolates. The mean death time (MDT) of SPF eggs infected with the P/Aus/3/11 isolate was 89.2 hr, characteristic of a mesogenic pathotype, consistent with other PPMV-1 strains. The plaque size of the P/Aus/3/11 isolate on chicken embryo fibroblast (CEF) cells was smaller than those of mesogenic and velogenic NDV reference strains, indicating a lower virulence phenotype in vitro and challenge of six-week-old SPF chickens did not induce clinical signs. However, sequence analysis of the fusion protein cleavage site demonstrated an ¹¹²RRQKRF¹¹⁷ motif, which is typical of a velogenic NDV pathotype. Phylogenetic analysis indicated that the P/Aus/3/11 isolate belongs to a distinct subgenotype within class II genotype VI of avian paramyxovirus type 1. This is the first time this genotype has been detected in Australia causing disease in domestic pigeons and is the first time since 2002 that an NDV with potential for virulence has been detected in Australia.     

新甲型H1N1流感病毒与流感大流行防治研究进展

由于甲型流感病毒基因高度变异的特点,导致其对不同种属宿主亲和力、毒力、免疫原性、抗药性不断发生变化,全球新型流感大流行的风险时刻存在.因此,应加强流感特别是重症流感发病机制和有效干预措施研究,从疫苗研制、开发新型抗病毒药、加强综合治疗,特别是调节宿主免疫反应等多个方面着手,为应对可能爆发的流感大流行提供对策.     

庚型肝炎病毒感染的临床流行情况和致病力的探讨

目的：为了弄清肝病患者中庚型肝炎病毒（ＨＧＶ）的临床感染情况和评估庚型肝炎病毒的致病力。方法：本文调查了２１３例肝病患者的ＨＧＶ感染情况和分析了ＨＧＶ感染的致病力。结果：在２１３例肝病患者中，ＨＧＶ的感染率为７５％（１６／２１３）；其中，ＨＧＶ与ＨＢＶ、ＨＣＶ以及ＨＢＶ和ＨＣＶ的合并感染分别是为７１％（９／１２７）、１８２％（２／１１）和２７８％（５／１８）。未发现ＨＢＶ合并ＨＧＶ感染和单独ＨＢＶ感染两组之间肝功能的损害程度存在差异。结论：以上结果提示，ＨＧＶ通常与胃肠外传播的ＨＢＶ和ＨＣＶ合并感染。而且，ＨＧＶ的致病力看来是温和的     

Natural Selection of H5N1 Avian Influenza A Viruses with Increased PA-X and NS1 Shutoff Activity

Influenza A viruses (IAV) can infect a broad range of mammalian and avian species. However, the host innate immune system provides defenses that restrict IAV replication and infection. Likewise, IAV have evolved to develop efficient mechanisms to counteract host antiviral responses to efficiently replicate in their hosts. The IAV PA-X and NS1 non-structural proteins are key virulence factors that modulate innate immune responses and virus pathogenicity during infection. To study the determinants of IAV pathogenicity and their functional co-evolution, we evaluated amino acid differences in the PA-X and NS1 proteins of early (1996–1997) and more recent (since 2016) H5N1 IAV. H5N1 IAV have zoonotic and pandemic potential and represent an important challenge both in poultry farming and human health. The results indicate that amino acid changes occurred over time, affecting the ability of these two non-structural H5N1 IAV proteins to inhibit gene expression and affecting virus pathogenicity. These results highlight the importance to monitor the evolution of these two virulence factors of IAV, which could result in enhanced viral replication and virulence.     

重组人硫氧还蛋白抗柯萨奇B3m病毒损伤的研究

目的 观察重组人硫氧还蛋白(TRX)对柯萨奇B3m病毒(CVB3m)致HeLa细胞损伤的保护作用,并检测TRX对病毒复制的抑制作用.方法 采用IOTCID50的CVB3m病毒感染HeLa细胞,给予不同剂量的TRX(2、5、10mg/L)加以保护,实验设TRX保护组、病毒感染组、TRX对照组和对照组,每组设6个复孔.采用四甲基偶氮唑盐(MTT)和相差显微镜观察细胞生长情况.结果 相差显微镜下对照组HeLa细胞排列紧密、呈多角形;病毒感染组HeLa细胞排列不紧密,细胞明显变网、脱落;TRX保护组(2、5、10 mg/L)随TRX剂量增加HeLa细胞形态明显改善.MTT结果显示,TRX对照组(2、5、10 mg/L)生长抑制率(1.2%、2.9%、6.3%)与对照组(0)比较,差异无统计学意义(P均>0.05);TRX保护组(2、5、10 mg/L)生长抑制率(32.0%、28.0%、27.0%)与病毒感染组(51.7%)比较,均有降低(P均<0.05).病毒复制抑制作用结果显示,TRX保护组(2、5、10 mg/L)生长抑制率(26.0%、27.0%、10.9%)与病毒感染组(60.0%)比较,均有降低(P均<0.05);TRX各保护组之间比较,低剂量组(2、5 mg/L)与高剂量组(10 mg/L)间差异有统计学意义(P均<0.05).结论 重组人TRX(2、5、10mg/L)可以减轻CVB3m病毒导致的HeLa细胞损伤,对细胞无明显毒性作用,并具有抑制病毒复制的作用.     

A new influenza virus virulence determinant: the NS1 protein four C-terminal residues modulate pathogenicity

The virulence of influenza virus is a multigenic trait. One determinant of virulence is the multifunctional NS1 protein that functions in several ways to defeat the cellular innate immune response. Recent large-scale genome sequence analysis of avian influenza virus isolates indicated that four C-terminal residues of the NS1 protein is a PDZ ligand domain of the X-S/T-X-V type and it was speculated that it may represent a virulence determinant. To test this hypothesis, by using mice as a model system, the four C-terminal amino acid residues of a number of influenza virus strains were engineered into the A/WSN/33 virus NS1 protein by reverse genetics and the pathogenicity of the viruses determined. Viruses containing NS1 sequences from the 1918 H1N1 and H5N1 highly pathogenic avian influenza (HPAI) viruses demonstrated increased virulence in infected mice compared with wt A/WSN/33 virus, as characterized by rapid loss of body weight, decreased survival time, and decreased mean lethal dose. Histopathological analysis of infected mouse lung tissues demonstrated severe alveolitis, hemorrhaging, and spread of the virus throughout the entire lung. The increase in pathogenicity was not caused by the overproduction of IFN, suggesting the NS1 protein C terminus may interact with PDZ-binding protein(s) and modulate pathogenicity through alternative mechanisms.     

Next-generation sequencing virulome analysis of a Yersinia enterocolitica subsp. palearctica bioserotype 4/O:3 ST18 isolated from human blood in Brazil

Yersinia enterocolitica is a widespread Gram-negative bacterium that causes gastrointestinal disease and other clinical manifestations in humans. Potentially pathogenic Y. enterocolitica has been isolated in Brazil, from human, environmental, food, and animal sources. Herein we report a genome sequence of Y. enterocolitica subsp. palearctica strain YE 19, serotype O:3, biotype 4, sequence type 18, with virulence determinants isolated from human blood in Rio de Janeiro in 2005. The results corroborate other findings that this strain harbors a set of virulence determinants that could play a role in host pathoadaptation and may also justify the successful dissemination of bioserotype 4/O:3 in Brazil. The presence of strains harboring all of these virulence genes in Brazil is a potential threat to young children and immunocompromised individuals, for whom yersiniosis are a significant source of morbidity and mortality. The results of a genomic data analysis will help understand the virulence of Brazilian strains and provide data for Y. enterocolitica studies worldwide.