WU多瘤病毒在中国浙江地区的发现与鉴定

呼吸道病毒种类很多,大部分的病毒感染机体后可以导致大面积人群不同程度的发病,严重的可导致死亡[1].     

急性呼吸道感染儿童中WU多瘤病毒基因组序列特征分析

为了解从北京地区急性呼吸道感染儿童中发现的WU多瘤病毒的基因组编码特征,并对其进行基因序列多样性分析,应用针对基因组5'端非编码区、衣壳蛋白VP1、VP2编码基因以及LTAg编码基因的引物对,从已确证为WU病毒阳性的来自北京地区急性呼吸道感染儿童的编号为BJF5276的临床标本中经聚合酶链反应扩增得到预期的基因片段,直接测序后将序列拼接得到全基因组序列,进而推导其基因组编码特征;随后从其它21例已确证为WU多瘤病毒阳性的急性呼吸道感染儿童标本中扩增得到衣壳蛋白VP2编码区基因,进行基因序列测定以及基因序列多样性分析。得到了WU病毒BJF5276全基因组序列。序列分析结果显示WU病毒BJF5276基因组序列全长为5229bp,共有5个主要的CDS(Coding domain sequences),分别编码衣壳蛋白VP2、VP3、VP1,并以其互补序列为模板,编码STAg和LTAg;所得到的22例VP2蛋白编码区基因序列同源性比较结果显示病毒VP2基因编码区序列与GenBank中已有的64个序列之间同源性很高;Mega4.0NJ进化树(Neighbor-joiningtree)分析显示这22个VP2基因序列分属于不同的基因进化簇,其中20个序列属于进化簇I中的Ia,另外2个序列属于进化簇III,其中的一个序列在IIIb基因进化簇中,另外一个序列独立成簇,不属于现有的IIIa或IIIb,暂时将其命名为IIIc。本研究结果提示北京地区的WU病毒具有多瘤病毒科的基因组编码特性;序列非常保守,有分属于不同基因进化簇的WU病毒在北京地区流行,与文献报道的以Ib流行为主所不同的是北京地区的WU病毒以Ia为主,且有新的基因进化簇出现。     

多瘤病毒感染与妇科肿瘤相关性的初步研究

人多瘤病毒(John Cunningham Virus,JCV)是广泛存在于人体内的一种多瘤病毒,最近二十年,国外研究显示JCV感染与多种神经系统及消化系统肿瘤高度相关,而JCV感染与妇科肿瘤关系的研究还鲜有报道。本研究在建立JCV核酸检测方法及规程的基础上,收集子宫肌瘤(98例)、子宫颈癌(84例)、子宫内膜癌(40例)、卵巢肿瘤(72例)患者临床资料、活检组织及血和尿样。运用PCR技术对上述患者活检样本及血、尿样本实施人乳头瘤病毒、单纯疱疹病毒Ⅱ型、人类疱疹病毒(Estein-barr virus,EBV)、巨细胞病毒和多瘤病毒JCV及BKV(B.K.virus,BKV)核酸检测。子宫颈癌高度相关人乳头瘤病毒在子宫颈癌组中检出率(19.0%)明显高于其它组,单纯疱疹病毒Ⅱ型、EBV及巨细胞病毒检出率几乎为0。BKV在尿样中的检出率明显高于血样及活检组织检出率,且检出率在各患者组中无显著差异。JCV检出率在血清样本及活检中几乎为0,然而,尿样中检测率均超过50%,且在子宫肌瘤患者组中高达65.3%。本研究显示JCV感染与子宫肌瘤高度相关,为子宫肌瘤的发病机理提供了新的病原学参考证据。     

北京地区住院患儿WU多瘤病毒感染的流行病学研究

自2007年Gaynor A M等人通过高通量测序在肺炎患儿呼吸道样本中发现了WU多瘤病毒(Washington University polyomavirus,WUPyV)以来,WUPyV在世界各地被广泛检出。为了解北京地区急性呼吸道感染住院儿童中WUPyV感染情况及其临床特征,收集北京地区2017年4月至2018年3月共1 276份呼吸道感染住院患儿的鼻咽抽吸物样本,使用real time PCR方法对样本进行WUPyV检测,同时对WUPyV阳性样本进行17种常见呼吸道病毒筛查。共检出WUPyV阳性样本76份(5.96%,76/1 276),4岁以下儿童居多(92.11%,70/76);WUPyV感染全年可见,无显著季节性;多伴随其他呼吸道病毒混合感染(60.53%,46/76),最常见混合感染为鼻病毒和A型流感病毒;WUPyV单一感染者与混合感染者病毒载量无显著性差异,临床诊断和表现基本一致;WUPyV感染患儿的常见诊断为支气管炎(68.42%,52/76)和肺炎(30.26%,23/76);临床症状主要表现为高热、咳嗽、咳痰。研究结果提示WUPyV是北京地区急性呼吸道感染住院患儿呼吸道样本中常见病毒之一,多见于4岁以下儿童。     

多瘤病毒分离株的研究

多瘤病毒注入新生小鼠体内后,可刺激小鼠组织细胞分裂繁殖、产生多种肿瘤。用肿瘤药物治疗后,从缩小的肿瘤块组织细胞中分离的多瘤病毒株有的已经不再能诱发肿瘤。本文研究了这种不能产生肿瘤的多瘤病毒株和野生型病毒株在分子遗传学上的区别。1材料与方法5一氟胞咯咤（5－F。）购于美国SIGMA公司,［’H卜胸腺喀＠、［‘’S〕一甲硫氨酸购一千英国RadiocheAncalCentreAmrsharn,兔抗鼠多瘤病毒幻灯免疫荧光试剂购于法国巴斯德研究所。1．且分离多瘤病毒的方法小鼠为NIH小鼠,新生小鼠皮下接种或腹腔内接种多瘤病毒悬液。有肿瘤生长…     

急性下呼吸道感染患儿中RSV的分离鉴定及分析

目的对2015年兰州单中心急性下呼吸道感染患儿中呼吸道合胞病毒(respiratory syncytial virus,RSV)进行分离鉴定及分析。方法收集临床急性下呼吸道感染患儿痰分泌物226份,在HEP-2细胞中连续盲传培养3代,收获的培养物用半巢式RT-PCR进行检测,选取强阳性样品进行测序以确定其型别,并对其流行病学特征进行分析。结果 226份样品中RSV阳性样本为76份(阳性率为34%)。RSV阳性患儿中,男女性别比为3∶1;年龄分布6月龄患儿占45%,6月龄~2岁占35%,2~5岁的占20%。冬季为发病高峰。76例RSV阳性患儿中,临床诊断依次为毛细支气管炎31例(40.79%)、喘息性支气管炎21例(27.36%)、支气管肺炎20例(26.32%)和支气管哮喘4例(5.26%)。40份强阳性RSV样品经测序确定为B亚型。结论 RSV是引起婴幼儿急性下呼吸道感染的重要病原之一,2015年RSV的流行株主要为B亚型。     

人多瘤病毒7 TaqMan探针实时定量PCR检测方法的建立

目的:建立人多瘤病毒7(HPy V7)核酸快速、特异的Taq Man探针实时定量PCR检测方法。方法:分别设计HPy V7特异性的引物与Taq Man探针,建立实时荧光定量PCR方法,并对其特异性、灵敏性和重复性进行评价;用建立的方法检测200份健康成人志愿者的血清和300份急性呼吸道感染住院儿童的鼻咽抽吸物样本。结果:所建立的实时定量PCR方法对HPy V7的检测灵敏度可达10拷贝/μL,检测线性范围为101~1010拷贝/μL,且实验特异性和重复性好(CV1.0%);采用该方法,从200份血清样本中检出9份阳性标本。结论:建立了HPy V7 Taq Man探针实时定量PCR检测方法,为HPy V7的流行病学调查及其初步研究提供了技术手段。     

儿童下呼吸道感染的金黄色葡萄球菌耐药性分析

对 4 2 38例下呼吸道感染患儿深部痰液标本中的金黄色葡萄球菌进行分离培养 ,并用细菌自动分析系统Vitek 6 0进行菌种鉴定和药物敏感试验。金黄色葡萄球菌分离阳性率为 2 .1% (89/ 4 2 38)。所分离的89株金黄色葡萄球菌中 ,95 .5 % (85 / 89)菌株产 β 内酰胺酶 ;但仅 4 .5 % (4 / 89)菌株耐苯唑西林 (MRSA) ,其中 3株显示多重耐药。 96 .6 %和 4 8.3%的菌株分别对青霉素和红霉素耐药 ,14 .6 %～ 2 5 .9%分别对四环素、林可霉素、复方新诺明耐药 ;对其余临床常用抗生素 ,如庆大霉素、苯唑西林、氨苄西林 /舒巴坦、阿莫西林 /克拉维酸、头孢唑啉、环丙沙星、左氧氟沙星等的耐药率均低于 10 %。上述实验结果提示 ,本地区引起患儿下呼吸道感染的金黄色葡萄球菌对多数临床常用抗生素仍敏感 ,β 内酰胺酶阳性菌株极为普遍 ,但MRSA所占比例不高。     

儿童下呼吸道感染病原菌分布及耐药性

目的对儿童下呼吸道感染病原菌分布情况及耐药情况进行分析。方法选取延安大学附属医院儿科2012年8月至2014年8月明确诊断的385例下呼吸道感染患儿,对其痰标本的培养结果进行统计,分析其病原菌分布及耐药情况。结果患儿痰培养阳性菌株134例,其中革兰阴性菌91株,以大肠埃希菌为主,占20.9%;革兰阳性菌40株,以金黄色葡萄球菌为主,占9.7%;真菌3株,占2.2%。对5种主要病原菌检出年度情况分析,显示大肠埃希菌、肺炎克雷伯杆菌、鲍曼不动杆菌检出率逐年增加,肺炎链球菌检出率逐年降低,而金黄色葡萄球菌三年无明显变化。婴儿组、幼儿组病原菌检出率显著高于学龄前及学龄组,病原菌检出率在年龄分布上差异有统计学意义(χ2=43.445,P0.01)。不同病原菌对常用抗菌药物呈现不同程度的耐药,革兰阴性菌对亚胺培南、美罗培南均敏感,对氨苄西林耐药率最高;金黄色葡萄球菌及肺炎链球菌对利奈唑胺及万古霉素敏感,对苄青霉素耐药率最高。结论儿童下呼吸道感染病原菌以革兰阴性菌为主,检出率在性别上无差异,婴儿、幼儿检出率高于学龄前及学龄儿童。治疗时应根据药敏试验结果,合理使用抗生素,降低耐药菌株的产生。     

鼠多瘤病毒样颗粒及其在疫苗开发等方面的研究进展

鼠多瘤病毒(murine polyomavirus,MPV)的病毒样颗粒(virus-like particle,VLP)是通过MPV的衣壳结构蛋白VP1自组装而成的球形纳米壳状结构. MPV VLP具有独特的纳米结构,在一定条件下能够进行体内或体外自组装,具有丰富的可修饰位点.因此,容易通过结构的修饰改造实现MPV VLP在诸多领域的应用.本文从MPV VLP的结构特点着眼,回顾MPV VLP的发现历程,介绍MPV VLP的制备表达系统和组装机理,综述MPV VLP的修饰.重点介绍化学修饰和基因工程修饰方法,并通过实例阐述MPV VLP在疫苗开发、药物及其他分子载体等领域的应用及其研究进展.基于对已有研究进展的分析,指出大规模生产、组装机理解析及其应用研究的关键环节,服务于MPV VLP的应用开发.     

Etiologic Diagnosis of Lower Respiratory Tract Infections

Decision as to the role of infection in lower respiratory tract disease requires examination by culture of specimens known to be derived from the infra-laryngeal respiratory tract. Methods that involve the upper respiratory tract in collection of specimens entail the hazard of contamination by microbiota resident in the upper respiratory tract.The extrapulmonary approaches of cutting-needle biopsy and needle aspiration of intrathoracic disease have not been impressively productive of etiologic diagnosis of infections. While open-chest surgical biopsy has been a highly effective means to diagnosis, this approach does have special requirements in facilities and technical skills.Percutaneous transtracheal aspiration of tracheo-broncho-pulmonary secretions-exudates has been productive of useful information. Because of inherent simplicity and safety, transtracheal aspiration should precede resort to more demanding, difficult, dangerous procedures.     

Detection of KI polyomavirus and WU polyomavirus DNA by real-time polymerase chain reaction in nasopharyngeal swabs and in normal lung and lung adenocarcinoma tissues

Polyomaviruses KI (KIPyV) and WU (WUPyV) were detected from 7 (3.0%) and 38 (16.4%) of 232 children with respiratory tract infections by real-time PCR. The rates of infection by KIPyV and WUPyV alone were 3 of 7 (42.9%) and 20 of 38 (52.6%), respectively. In the other samples, various viruses (human respiratory syncytial virus, human metapneumovirus, human rhinovirus, parainfluenza virus 1 and human bocavirus) were detected simultaneously. One case was positive for KIPyV, WUPyV and hMPV. There was no obvious difference in clinical symptoms between KIPyV-positive and WUPyV-positive patients with or without coinfection. KIPyV was detected in one of 30 specimens of lung tissue (3.3%). Neither of the viruses was detected in 30 samples of lung adenocarcinoma tissue.     

A multi-center study on Molecular Epidemiology of Human Respiratory Syncytial Virus from Children with Acute Lower Respiratory Tract Infections in the Mainland of China between 2015 and 2019

Virologica Sinica - Human respiratory syncytial virus (RSV) is a major pathogen of acute lower respiratory tract infection among young children. To investigate the prevalence and genetic...     

Airway Interleukin-8 in Elderly Patients with Bacterial Lower Respiratory Tract Infections

We investigated the interleukin-8 (IL-8) levels and neutrophil numbers in the sputum of 9 elderly patients with lower respiratory tract infections, including Pseudomonas aeruginosa infection, before and after treatment with various antimicrobial agents. The IL-8 levels in sputum supernatants and the neutrophil numbers in sputum smears from 9 patients decreased significantly after the elimination of the causative respiratory pathogens. We also demonstrated that human recombinant IL-8 at a range of 6.25-25 ng/ml significantly enhanced opsonophagocytic killing of P. aeruginosa immunotype-1 strain by human neutrophils in the presence of a serotype-specific anti-lipopolysaccharide monoclonal antibody and fresh normal human serum. These data suggest that the level of IL-8 production in the airways of patients with lower respiratory tract infections is dependent on bacterial densities, and indicate the important role of IL-8 not only in neutrophil migration but also in opsonophagocytic killing of bacteria in the lower respiratory tract.     

Viral Co-Infections in Pediatric Patients Hospitalized with Lower Tract Acute Respiratory Infections

Background

Molecular techniques can often reveal a broader range of pathogens in respiratory infections. We aim to investigate the prevalence and age pattern of viral co-infection in children hospitalized with lower tract acute respiratory infection (LT-ARI), using molecular techniques.

Methods

A nested polymerase chain reaction approach was used to detect Influenza (A, B), metapneumovirus, respiratory syncytial virus (RSV), parainfluenza (1–4), rhinovirus, adenovirus (A—F), bocavirus and coronaviruses (NL63, 229E, OC43) in respiratory samples of children with acute respiratory infection prospectively admitted to any of the GENDRES network hospitals between 2011–2013. The results were corroborated in an independent cohort collected in the UK.

Results

A total of 204 and 97 nasopharyngeal samples were collected in the GENDRES and UK cohorts, respectively. In both cohorts, RSV was the most frequent pathogen (52.9% and 36.1% of the cohorts, respectively). Co-infection with multiple viruses was found in 92 samples (45.1%) and 29 samples (29.9%), respectively; this was most frequent in the 12–24 months age group. The most frequently observed co-infection patterns were RSV—Rhinovirus (23 patients, 11.3%, GENDRES cohort) and RSV—bocavirus / bocavirus—influenza (5 patients, 5.2%, UK cohort).

Conclusion

The presence of more than one virus in pediatric patients admitted to hospital with LT-ARI is very frequent and seems to peak at 12–24 months of age. The clinical significance of these findings is unclear but should warrant further analysis.     

Prevalence and Correlation of Infectious Agents in Hospitalized Children with Acute Respiratory Tract Infections in Central China

Acute respiratory tract infections (ARTIs) are associated with significant morbidity and mortality worldwide, especially in children under the age of 5 years. Almost 2 million children die from ARTIs each year, and most of them are from developing countries. The prevalence and correlation of pathogens in ARTIs are poorly understood, but are critical for improving case prevention, treatment, and management. In this study, we investigated the prevalence and correlation of infectious agents in children with ARTIs. A total of 39,756 children with one or more symptoms, including fever, cough, sore throat, tonsillitis, pharyngitis, herpangina, pneumonia, and bronchiolitis, were enrolled in the study. All patients were hospitalized in Wuhan Children’s Hospital between October 1, 2010 and September 30, 2012, and were evaluated for infectious agents. Pathogens, including Mycoplasma pneumoniae, influenza A virus, influenza B virus, adenoviruses, respiratory syncytial virus, parainfluenza virus, Legionella pneumophila, Chlamydophila pneumoniae, and Coxiella burnetii, were screened simultaneously in patient blood samples using anti-pathogen IgM tests. Regression analysis was used to reveal correlations among the pathogens. Our results showed that one or more pathogens were identified in 10,206 patients, and that Mycoplasma pneumoniae, adenoviruses, and influenza B virus were the leading infectious agents. Mixed-infections of pathogens were detected in 2,391 cases, with Mycoplasma pneumoniae as the most frequent pathogen. The most common agents in the co-infections were Mycoplasma pneumoniae and influenza B virus. Regression analysis revealed a linear correlation between the proportion of mixed infections and the incidence of multi-pathogen infections. The prevalence of infectious agents in children with ARTIs was determined. Equations were established to estimate multiple infections by single-pathogen detection. This revealed a linear correlation for pathogens in children with ARTIs. This study provides useful information for improving case prevention and management.     

Aetiology of Acute Respiratory Tract Infections in Hospitalised Children in Cyprus

In order to improve clinical management and prevention of viral infections in hospitalised children improved etiological insight is needed. The aim of the present study was to assess the spectrum of respiratory viral pathogens in children admitted to hospital with acute respiratory tract infections in Cyprus. For this purpose nasopharyngeal swab samples from 424 children less than 12 years of age with acute respiratory tract infections were collected over three epidemic seasons and were analysed for the presence of the most common 15 respiratory viruses. A viral pathogen was identified in 86% of the samples, with multiple infections being observed in almost 20% of the samples. The most frequently detected viruses were RSV (30.4%) and Rhinovirus (27.4%). RSV exhibited a clear seasonality with marked peaks in January/February, while rhinovirus infections did not exhibit a pronounced seasonality being detected almost throughout the year. While RSV and PIV3 incidence decreased significantly with age, the opposite was observed for influenza A and B as well as adenovirus infections. The data presented expand our understanding of the epidemiology of viral respiratory tract infections in Cypriot children and will be helpful to the clinicians and researchers interested in the treatment and control of viral respiratory tract infections.