中缅树鼩自然感染五种高致病性人腺病毒的血清流行病学分析

目的 分析中缅树鼩(Tupaiabelangeri, Tree Shrew)自然感染5种高致病性人腺病毒(Human Adenovirus, HAdv)的血清流行病学,以探讨人腺病毒感染树鼩的可能性。方法 采用固定病毒稀释血清法测定34份树鼩血清对Ad3、Ad4、Ad7、Ad14和Ad55的中和抗体水平。结果 4种B组腺病毒的中和抗体阳性率及中和效价较E组4型的大,阳性率由大到小依次为:Ad14(55.88%)、Ad3(47.06%)、Ad55(29.71%)、Ad7(14.71%)、Ad4(8.82%),树鼩血清主要表现为Ad3、Ad14和Ad55混合型多价抗血清。结论 中缅树鼩可自然感染5种人腺病毒,有望以树鼩为实验动物,建立一种成熟的人腺病毒感染模型。     

中国病毒性腹泻的病原学研究

<正> 1982～1986年收集因腹泻住院的2岁以下病儿粪便标本975份,电镜检查结果408份检出病毒(41.8％),其中轮状病毒370份(37.9％)、腺病毒27份(2.8％)、小圆病毒11份(1.1％),证实轮状病毒是婴幼儿腹泻的重要病原。     

中缅树鼩常见病原菌的分离鉴定

目的调查中缅树鼩常见病原细菌携带情况。方法通过病原体分离培养、系列生化试验、血清学鉴定和核糖体16s rDNA分型技术对树鼩携带的细菌进行分离鉴定。结果从树鼩肠道和体表分离到金黄色葡萄球菌、表皮葡萄球菌、链球菌、绿脓杆菌、变形杆菌、大肠埃希菌、沙雷菌,未分离到沙门氏菌、志贺菌、克雷伯菌和产气杆菌。结论树鼩携带多种病原菌,建立树鼩病原菌的检测方法是树鼩实验动物化和质量监测的重要内容。     

深圳市盐田区人群肠道病毒及常见感染性腹泻病毒调查分析

目的 了解深圳市盐田区人群肠道病毒及常见感染性腹泻病毒隐性感染状况,为制定防控措施提供科学依据。 方法 2020 年在盐田区海山、沙头角、盐田、梅沙四个街道,分别整群随机抽取 1 个社区为调查点,采集居民粪便样本用实时荧光定量 PCR 方法检测诺如病毒、札如病毒、轮状病毒、星状病毒、肠道腺病毒、肠道病毒通用型、肠道病毒 71 型(EV71)和柯萨奇病毒 A16 型(CV-A16)。 结果 共收集并检测粪便样品 813 份,未检出札如病毒、轮状病毒、星状病毒、肠道腺病毒、EV71 和 CA16;检出肠道病毒通用型 2 例,阳性率为 0. 25%,均为幼童口服脊髓灰质炎疫苗所致;检出诺如病毒 4 例,均为诺如 GⅡ型,阳性率为 0. 49%。 4 例诺如病毒阳性样本成功测序 2 例,分别为 GⅡ. 2-GⅡ. P16 型和 GⅡ. 17-GⅡ. P17 型,均与近年国内流行株有较高同源性。 结论 深圳市盐田区人群存在诺如病毒隐性感染,应加强对重点人群、重点场所的监测。     

丙型肝炎病毒体外可感染树鼩肝细胞

目的 探讨丙型肝炎病毒（HCV）体外感染树目句原代肝细胞。方法 用HCV RNA阳性血清感染原代树鼩肝细胞，并用感染后细胞培养上清液进行传代感染，通过检测受染肝细胞正、负链HCV RNA、培养上清液中包装后HCV RNA，并对比分析感染前后病毒准种变化等指标，评价感染是否成功。结果 受染树鼩肝细胞自第5～10天可检出负链HCV RNA，而正链RNA至感染后第14天仍可检出；感染后3～14d培养上清液中可检出HCV RNA，且呈RNA酶抗性；培养上清液中病毒可传代感染新的树鼩肝细胞；感染前后HCV准种分析显示树鼩肝细胞可被特定的准种选择性感染，而传代感染后肝细胞可检出新的准种。结论 原代树鼩肝细胞体外可被HCV感染且支持病毒复制。     

HDV/HBV感染树鼩肝组织ICE表达及肝细胞凋亡

目的 探讨HDV/HBV感染树鼩肝组织中ICE表达与HDV感染之间的关系,以及ICE在丁型肝炎肝细胞凋亡中的作用。 方法 采用免疫组化技术对45份HDV感染树鼩肝组织中HDVAg,ICE的表达进行了检测;应用原位末端标记技术对肝组织凋亡进行检测;并应用免疫组化双重染色对HDVAg,ICE的表达以及肝细胞凋亡进行了检测。 结果 肝组织45份中有43份可检出ICE(阳性率96％),有41份可检出凋亡细胞(阳性率91％),ICE在肝细胞浆和(或)膜上表达,以肝细胞浆内表达为主,HDVAg表达与ICE表达之间有显著相关性X~2=36.2(P<0.05),HDVAg表达越强,ICE表达越强,凋亡阳性细胞在肝细胞索多呈散在分布,在坏死灶中也可检出,凋亡在HDVAg阳性和阴性细胞中均可发生,以在HDVAg阳性细胞内发生为主,ICE表达与肝细胞凋亡之间有显著相关性X~2=35.6(P<0.05),ICE表达越强,凋亡阳性细胞越多。 结论 丁型肝炎病毒感染和未感染的肝细胞均可发生凋亡,但凋亡只在少数细胞内发生;HDV可诱导ICE表达,ICE在肝细胞凋亡中起重要作用。     

布鲁属马来丝虫、彭亨丝虫、树鼩丝虫及吴策属班氏丝虫的鉴别

本文作者从流行病学观点出发,对亚周期型马来布鲁丝虫(Brugia malayi)、周期型马来布鲁丝虫、彭亨布鲁丝虫(B.pahangi)、树鼩布鲁丝虫(B.tupaiae)及班氏吴策丝虫(Wuchereria bancrofti)的微丝蚴一些形态上的差别进行了观察。亚周期型和周期型马来布鲁微丝蚴分别取自泰国南部陶公府和春蓬地区的人血;彭亨布鲁微丝蚴取自保种的猫血;树鼩布鲁微丝蚴属于白天周期型,取自泰国西部北碧捕来的普通树鼩(Tupaia glis);周期型和亚周期型班氏吴策微丝蚴分别取自斯里兰卡和泰国北碧的人血。将取得的血液分别制成厚涂     

用人工繁育的围生期和幼年树鼠句感染人乙型肝炎病毒的初步研究

目的通过用人工繁育的围生期和幼年树鼩接种人乙型肝炎病毒(HBV),并优选感染指标的检测方法,提高树鼩对HBV的感染率及检出方法的敏感性和可靠性。方法用人HBV阳性血清接种42只人工繁育的围生期和幼年树鼩,选择合适的引物,经巢式PCR(nPCR)技术检测它们肝组织及血清的HBV DNA,并对扩增出的DNA片段进行测序验证,以及对活检肝组织作病理组织学观察。结果接种后动物的肝组织和血清HBV DNA的阳性率分别为47.6%(20/42)和71.4%(30/42),肝组织和血清共同阳性的为40.5%(17/42),总阳性率为78.6%(33/42);扩增的DNA片段经测序与人HBV DNA相应片段的同源性为98%和99%;肝组织病理改变以轻度炎性病变较多见。结论用人工繁育的围生期和幼年树鼩感染HBV,可提高树鼩对HBV的感染效率;用nPCR技术及选择合适的引物配对检测肝组织和血清标本的HBV DNA,是评价树鼩感染HBV状况的敏感、可靠方法。     

使用免疫电镜在泰国NANB肝炎病人粪便中检出27～32nm的病毒样颗粒

已有许多国家报道肠道传播的非非甲乙型(NANB)肝炎(ET-NANB),从病人粪便中检出27～含27～34mm 颗粒(VLP)。灵长类动物实验已证明,34nm 的病毒样 VLP 的粪便可引起 NANB 肝炎。本文使用免疫电镜(IEM)技术研究 ET-NANB 肝炎在泰国的分布。     

嗜血杆菌属CODEHOP PCR检测方法的建立及在树鼩检测中的应用

目的建立树鼩中嗜血杆菌的CODEHOP PCR快速检测方法,为树鼩微生物质量控制提供参考。方法应用CODEHOP在线简并引物设计工具,比对NCBI中6株嗜血杆菌的外膜蛋白序列设计简并引物。通过4株嗜血杆菌标准菌株和24株它属菌株进行特异性和敏感性评价,将建立CODEHOP PCR检测方法,应用于树鼩嗜血杆菌的检测。结果简并引物HF1/HR8和HF3/HR3扩增标准菌株副鸡嗜血杆菌(ATCC 29545)、溶血嗜血杆菌(ATCC 33390)、流感嗜血杆菌(ATCC 33391)、副流感嗜血杆菌(ATCC 33392)的目的片段分别为506 bp~535 bp和344 bp~390 bp,经测序和NCBI Blast比对,结果准确。两对引物组合,能够有效的区分嗜血杆菌属菌株与它属菌株,检测限最低可达2.1 pg/μL。在受试的野生树鼩呼吸道样本中嗜血杆菌阳性率为33.3%(20/60)。结论所建立的方法具有较好的特异性和敏感性,操作简便,能够用于动物样品的嗜血杆菌检测。     

Tree Shrew as an Emerging Small Animal Model for Human Viral Infection: A Recent Overview

Viral infection is a global public health threat causing millions of deaths. A suitable small animal model is essential for viral pathogenesis and host response studies that could be used in antiviral and vaccine development. The tree shrew (Tupaia belangeri or Tupaia belangeri chinenesis), a squirrel-like non-primate small mammal in the Tupaiidae family, has been reported to be susceptible to important human viral pathogens, including hepatitis viruses (e.g., HBV, HCV), respiratory viruses (influenza viruses, SARS-CoV-2, human adenovirus B), arboviruses (Zika virus and dengue virus), and other viruses (e.g., herpes simplex virus, etc.). The pathogenesis of these viruses is not fully understood due to the lack of an economically feasible suitable small animal model mimicking natural infection of human diseases. The tree shrew model significantly contributes towards a better understanding of the infection and pathogenesis of these important human pathogens, highlighting its potential to be used as a viable viral infection model of human viruses. Therefore, in this review, we summarize updates regarding human viral infection in the tree shrew model, which highlights the potential of the tree shrew to be utilized for human viral infection and pathogenesis studies.     

Evaluation of human enteric viruses in surface water and drinking water resources in southern Ghana

An estimated 884 million people worldwide do not have access to an improved drinking water source, and the microbial quality of these sources is often unknown. In this study, a combined tangential flow, hollow fiber ultrafiltration (UF), and real-time PCR method was applied to large volume (100 L) groundwater (N = 4), surface water (N = 9), and finished (i.e., receiving treatment) drinking water (N = 6) samples for the evaluation of human enteric viruses and bacterial indicators. Human enteric viruses including norovirus GI and GII, adenovirus, and polyomavirus were detected in five different samples including one groundwater, three surface water, and one drinking water sample. Total coliforms and Escherichia coli assessed for each sample before and after UF revealed a lack of correlation between bacterial indicators and the presence of human enteric viruses.     

Detection and Molecular Characterization of Enteric Viruses in Bivalve Mollusks Collected in Arraial do Cabo,Rio de Janeiro,Brazil

Viral bivalve contamination is a recognized food safety hazard. Therefore, this study investigated the detection rates, seasonality, quantification, and genetic diversity of enteric viruses in bivalve samples (mussels and oysters). We collected 97 shellfish samples between March 2018 and February 2020. The screening of samples by qPCR or RT-qPCR revealed the detection of norovirus (42.3%), rotavirus A (RVA; 16.5%), human adenovirus (HAdV; 24.7%), and human bocavirus (HBoV; 13.4%). There was no detection of hepatitis A virus. In total, 58.8% of shellfish samples tested positive for one or more viruses, with 42.1% of positive samples contaminated with two or more viruses. Norovirus showed the highest median viral load (3.3 × 10⁶ GC/g), followed by HAdV (median of 3.5 × 10⁴ GC/g), RVA (median of 1.5 × 10³ GC/g), and HBoV (median of 1.3 × 10³ GC/g). Phylogenetic analysis revealed that norovirus strains belonged to genotype GII.12[P16], RVA to genotype I2, HAdV to types -C2, -C5, and -F40, and HBoV to genotypes -1 and -2. Our results demonstrate the viral contamination of bivalves, emphasizing the need for virological monitoring programs to ensure the quality and safety of shellfish for human consumption and as a valuable surveillance tool to monitor emerging viruses and novel variants.     

新生期树鼩接种人乙型肝炎病毒的长期实验观察

目的 观察新生期树鼩接种HBV后体内HBV感染标志物的长期动态.方法 6只树鼩于新生期接种人HBV DNA阳性血清,每4-6周抽血1次和每6～12周做肝活体组织检查1次,应用巢式聚合酶链反应(nPCR)、荧光定量聚合酶链反应(FQ-PCR)、Southern blot、酶联免疫吸附试验和免疫组织化学染色等方法动态观察血清和肝组织中HBV感染标志物的消长,用电镜寻找肝组织内的HBV颗粒和用光镜观察肝组织病理变化.结果 新生期树鼩接种后48周,3只动物(1、2和6号)血清和肝组织标本经多对引物进行的nPCR,均稳定显示HBV DNA阳性,肝组织HBVcccDNA阳性;FQ-PCR显示血清和肝组织HBV DNA的拷贝数分别为103-104/ml和每微克肝组织总DNA 107～108拷贝;Southern blot检测显示肝组织存在HBV复制中间体HBV cccDNA和HBV单链DNA;酶联免疫吸附试验检测显示血清HBsAg持续阳性;免疫组织化学染色可见数量逐步增多的HBsAg阳性肝细胞.其中的1号动物至接种后2年每微克肝组织总DNA仍可测得107～108拷贝的HBV DNA,电镜下可见疑似HBV颗粒.另3只动物除nPCR显示肝组织HBV DNA阳性条带和FQ-PCR显示低拷贝数(每微克肝组织总DNA103拷贝)HBV DNA外,其余的HBV感染标志物均为阴性或一过性阳性.结论 新生树鼩能够长期感染HBV,并且HBV能够在树鼩体内稳定复制和长期存在.     

Enteric viral infections as a cause of diarrhoea in the acquired immunodeficiency syndrome

Background and aims The role of non-cytomegalovirus (CMV) enteric viral infection in causing diarrhoea in patients with human immunodeficiency virus (HIV) is poorly understood. We aimed to investigate the prevalence of these infections in acute and chronic diarrhoea. Methods Stool specimens from 377 HIV-infected patients presenting with diarrhoea were studied prospectively for evidence of non-CMV enteric viral infection. Patients with diarrhoea underwent investigation for gastrointestinal pathogens, including electron microscopic examination of stool for enteric viruses. We collected data on patients in whom enteric virus was identified and examined the association of enteric virus infection with diarrhoeal symptomatology. Results Eighty-nine (10.3%) stool specimens from 60 (15.9%) HIV⁺ individuals were positive for coronavirus (n = 13, 22%), rotavirus (n = 11, 18%), adenovirus (n = 30, 50%) and small round structured viruses (n = 5, 8%) or dual infection (n = 2, 3%). Thirty-four of 52 (65%) patients available for analysis had acute diarrhoea, and 18/52 (35%) had chronic diarrhoea. Twenty-three of 52 (44%) patients had a concurrent gut pathogen. After exclusion of concurrent pathogens enteric viral infections were found to be significantly associated with acute as opposed to chronic diarrhoea (P = 0.004). The presence of adenovirus colitis was significantly more likely to be associated with chronic diarrhoea (15/21 cases) than adenovirus isolated from stool alone (9/23 cases) (P = 0.03). There was a trend towards an association between adenovirus colitis and colonic cytomegalovirus infection (P = 0.06). Conclusion Enteric viral infection is strongly associated with acute diarrhoea in patients with HIV. Light microscopic examination of large bowel biopsies can identify adenovirus colitis which is significantly associated with chronic diarrhoea, and in addition may facilitate gastrointestinal co-infection with CMV.     

Transmission of viral infections by the water route: implications for developing countries

The "enteric" virus group comprises greater than 100 different viruses. These viruses typically infect the cell lining of the alimentary canal and are discharged in very large numbers in the feces of infected persons. Contamination of water supplies by enteric viruses represents an important source of viral infection. Many communities, particularly in developing countries, depend on sewage-polluted sources for their recreational and drinking water. Because conventional methods of sewage and water treatment have proved inefficient in the removal and inactivation of most enteric viruses, great concern has been raised over the impact of waterborne infection on the health of such communities. Current evidence implicating drinking and recreational water supplies in the transmission of nonbacterial gastroenteritis and hepatitis A virus and adenovirus infections is overwhelming. Water-borne transmission of other enteric viruses is also possible. Effective antiviral drugs are generally unavailable, and current vaccines can control only a limited number of viral infections; therefore, provision of uncontaminated water is a basic requirement in raising the standard of health in affected communities.     

In vitro isolation of stable rat sarcoma viruses

A Sprague-Dawley (SD-1) rat embryo culture, at low passage level, released an endogenous ecotropic type C virus (SD-RaLV) and after about 20 further passages it underwent spontaneous transformation. The SD-RaLV, released from the transformed cells, did not cause rapid transformation of other rat embryo cells. However, when the transformed cells were repeatedly cocultivated with three different chemically transformed and serially transplanted rat tumor cell lines (sarcoma, carcinoma, and hepatoma), rapidly fibroblast-transforming "sarcoma" viruses (RaSV) were recovered after each attempt. RaSV was not recovered from one of these tumor cell lines before transplantation, nor could focus-forming virus be rescued from these same tumor cells by cocultivation with other cells releasing heterologous type C viruses. Foci were induced on normal rat kidney and several other rat embryo cell strains within 7-15 days and both productive and nonproductive NRK clones were derived. The productive clones were positive for rat specific p30 antigen and the RaSVs released were serially transmitted to other rat embryo cells. RaSV genome was rescued from the nonproductive clones by superinfection with SD-RaLV, wild rat type C virus, and several heterologous type C viruses. These observations appear to represent naturally occurring transformation-specific (src) genes being recovered in vitro in the form of stable "sarcoma" viruses. These viruses differ from the Kirsten and Harvey strains of murine sarcoma virus in that they apparently contain no MuLV sequences and are of purely rat origin.     

Diarrhea and enteric emerging viruses in HIV-infected patients.

To evaluate the prevalence of enteric viruses and their possible association with diarrhea, 244 stool samples were collected from HIV-infected and uninfected patients with or without diarrhea (subgroups I-a, Ib, II-a, and II-b, respectively). Subjects were screened by polyacrylamide gel electrophoresis, latex agglutination, and enzyme immunoassays for rotaviruses, adenoviruses, picobirnaviruses, and astroviruses. Enteric viruses were found significantly more often in specimens from HIV patients (20%) than in specimens from uninfected HIV patients (0%) (p < 0.05). Picobirnavirus was detected in 14.63% of 82 HIV-infected patients with diarrhea, but it was detected neither in those without diarrhea (0%) (p < 0.05) nor in the groups of uninfected HIV subjects (0%) (p < 0.05). Nor could astrovirus (subgroups I-a [4.00%] versus subgroup I-b [5.26%],p > 0.05) or enteric adenovirus (subgroup I-a [1.22%] versus subgroup I-b [0%], p > 0.05) be linked to the diarrhea disorder in HIV-infected patients. Rotaviruses were not detected in any of the clinical subgroups studied. Enteric viruses were detected in 15 of 93 (16.13%) of the HIV-infected patients with CD4+ T cell count <200/microl and 3 of 19 (15.79%) of those HIV-infected individuals with a CD4+ T cell count 200-499/microl, showing no significant difference (p > 0.05). According to our data, unusual enteric viruses such as picobirnavirus, astrovirus, and enteric adenovirus occur in HIV-infected population in Córdoba, Argentina. However, only picobirnaviruses could be significantly associated with diarrhea in these patients.