2017-2021年安徽省麻疹病毒N基因羧基末端基因特征分析

目的 了解2017—2021年安徽省麻疹病毒N基因羧基末端基因特征。方法 采用反转录聚合酶链式反应（RT-PCR）方法扩增麻疹病毒N基因C末端450个核苷酸片段,对扩增产物进行核苷酸序列测定和基因特征分析。结果 2017—2021年安徽省监测到47株H1基因型,2株D8基因型,1株B3基因型和15株A基因型。结论 2017—2018年H1型仍然是安徽省麻疹流行的优势株,2018年后未监测到H1基因型;输入性病例未引起暴发和流行。安徽省需进一步加强病原学鉴定,及时发现输入性麻疹病例并阻断其传播。     

简便HBV基因型S基因PCR-RFLP分型方法的建立

目的 建立简便HBV基因型S基因PCR-限制性片段长度多态性(RFLP)分型方法(以下简称“简便PCR-RFLP法”),并评价其临床应用价值.方法 临床诊断研究.查阅并比较GenBank中128株HBV(基因型A～D型)S基因片段(S区nt253-687),设计限制性内切酶Hinf Ⅰ、Ear Ⅰ、Apo Ⅰ鉴别A～D基因型分型方法,并评价简便PCR-RFLP法检测HBV DNA的最低检测下限、重复性;然后,用该方法检测50例慢性乙型重型肝炎患者的HBV基因型,同时用直接测序法验证简便PCR-RFLP法检测HBV基因型的一致性.结果 建立了简便PCR-RFLP法HBV基因分型的方案,通过限制性内切酶Hinf Ⅰ一次酶切就可分出我国流行的B型、C型、D型等毒株及B/C混合型.随机抽取3份标本,不同稀释浓度下,用简便PCR-RFLP法重复检测HBV基因型,分型结果均与原血清完全一致,且最低检测下限约为7 ～9 IU/ml.经Hinf Ⅰ酶一步酶切后,用简便PCR-RFLP法从50例患者标本中,检出B型23份、C型10份;经直接测序法验证,从PCR产物中检出B型23份、C型10份,2种方法检测B、C型基因结果完全一致(Kappa=1.00,P=0.001),简便PCR-RFLP法检出B/C混合型9份,优于PCR产物直接测序法(0份,x2=18.00,P=0.001).Hinf Ⅰ酶一步酶切后分出的ABD型8份,进一步酶切及应用PCR产物直接测序法检测均为B型变异株.结论 建立的简便PCR-RFLP法对HBV基因分型有较高的灵敏度和重复性,且在检出混合基因型方面具有优势,更为简便.     

2013年北京市首例输入性D_9基因型麻疹毒株的分离和鉴定

目的分离并鉴定北京市输入性D9基因型麻疹毒株。方法使用Vero/SLAM细胞,对可疑麻疹输入性病例的咽拭子和尿液标本进行麻疹毒株的分离培养。用反转录-聚合酶链反应扩增麻疹病毒核蛋白(N)基因羧基末端676个核苷酸片段,对扩增产物进行核苷酸序列测定和分析,并以羧基末端450个核苷酸片段构建基因亲缘关系树,进行遗传距离及核苷酸同源性分析。结果该病毒分离株BJCY13026-2和世界卫生组织D9基因型代表株Victoria.AUS(维多利亚.澳大利亚)12.99在基因亲缘性关系树上同属一个分支,核苷酸同源性为95.8%,氨基酸同源性为96%;和其他23个基因型代表株的核苷酸和氨基酸同源性分别在88.1%~95.6%和90.7%~96.7%。和中国大陆目前所使用的麻疹疫苗株沪191相比对,其核苷酸和氨基酸同源性分别为91.1%和90.0%;和中国目前流行的麻疹病毒绝对优势本土基因型H1a基因型代表株相比对,其核苷酸和氨基酸同源性分别为89.4%和91.3%。结论该输入性病例的病毒分离株为麻疹病毒D9基因型。     

天津市麻疹病毒变异性分析

[目的]研究麻疹病毒(MV)流行株的变异性从而初探2002年天津地区MV基因型。[方法]将2002年天津市分离到的12株MV用绒猴淋巴细胞(B95a)复苏后，提取总RNA，采用逆转录一聚合酶链反应(RT-PCR)扩增出核蛋白(N)基因碳木端590个核苷酸片段，用BcnI内限酶进行限制性片段长度多态性分析(RFIP)后，选取3株与PMD-18T Vector构建重组质粒，测序后进行序列系统树分析。[结果]RT-PCR后12份均检测出590bp的特异性目的条带，3株测序分析均为麻疹病毒H1基因型，其中1株为H1b亚型，另外两株为H1a亚型。[结论]2002年天津市麻疹病毒为H基因型，本研究中所建立的实验方法可用于临床和流行病学研究。     

新疆部分地区麻疹野病毒分离与基因特征分析

目的 探讨新疆目前流行的麻疹病毒的基因型别和特征。方法 采用 Vero/SLAM 细胞分离培养麻疹病毒,通过反转录－聚合酶链反应方法扩增麻疹病毒 N 基因羧基末端456 bp片段,并对 PCR 产物进行序列测定和同源性分析。结果 2013-2014年新疆分离到7株麻疹病毒均为H1a基因亚型,与Shanghai-191同源性为89.5%～87.3%;与世界卫生组织推荐用于鉴定基因型别的6株H1基因型同源性为91.0%～99.3%,与目前3株流行H1a亚型同源性为97.3%～100.0%。结论 H1a基因亚型仍为新疆本土流行病毒株的优势亚型,近年来引起新疆麻疹流行的麻疹病毒基因序列存在着不同程度的差异,可能来自于不同的传播链,麻疹病毒株H1a亚型的持续传播与易感人群的累积和人口流动有密切关系。     

陕西省2000-2007年麻疹野病毒基因特征分析

目的阐明2000-2007年陕西省流行的麻疹野病毒分离株的基因特征,为控制并消除麻疹提供依据。方法2000-2007年采集陕西省麻疹暴发和散发患者的咽喉拭子标本147份,用EB病毒转化的狨猴淋巴母细胞（B95a）分离到麻疹病毒21株,通过逆转录-聚合酶链反应（RT-PCR）,从分离到的麻疹病毒株中扩增出核蛋白基因羧基末端450个核苷酸片段,再对扩增产物进行核苷酸序列测定和基因分型。结果21株麻疹病毒均属H1基因型,其中H1a18株,H1b3株,H1a和H1b在450个核苷酸片段中的差异为2％～4％。结论H1a和H1b在陕西省的流行状况提示,流行优势株的变化可能受本土病毒变异和邻省输入病毒的双重影响;同时在陕西省存在同一毒株的持续循环。     

构建乙型肝炎病毒基因参照品判断基因分型的探讨

目的利用乙型肝炎病毒（HBV）基因参照品判断HBV基因分型。方法自行制备HBV—S区基因参照品A、B、C、D型并测序及比较同源性，利用限制性内切酶MboI、EarI酶切参照品和样品扩增产物，从而确定样品基因型。利用该方法对克拉玛依地区272例HBV—DNA阳性血清基因分型。结果测序证实，HBV基因参照品与39例GenBank序列同源性均在96％以上。272例样品成功分型241例（88．6％）。检出B、C、D型，未检测到A型。抽检12例测序同源性大于96％。结论依据基因参照品核酸碱基片段大小判断分型，简明直观，适用于大样本的筛检及临床应用。     

中国羊种布鲁氏菌<I>omp2</I>基因PstⅠ酶切多态性特征分析

目的拟发现中国羊种布鲁氏菌Iomp2/I基因PstⅠ酶切多态性特征。方法用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）对羊种标准菌株、疫苗株M5、国内分离的羊种布鲁氏菌野毒株及非典型株共46株进行分析。结果Iomp2/I基因扩增产物经PstⅠ酶切后呈现两种酶切图谱,43/46有238 bp和44 bp 2个条带;仅羊1型标准株16M和两株青海非典型羊种1型菌有282 bp、238 bp和44 bp 3个条带。结论Iomp2/I基因PstⅠ酶切可为区分部分野生动物中的羊种菌和家畜羊种菌,为揭示布鲁氏菌的遗传衍化关系提供线索。     

宜春市2015年麻疹病毒野病毒感染病例的快速鉴别

目的 引进并运用逆转录多聚酶链式反应-限制性片段长度多态性分析方法(RT-PCR-RFLP方法)快速鉴别2015年宜春市麻疹野病毒感染病例与疫苗株病毒引起的相关麻疹病例.方法 运用realtime RT-PCR对宜春市400例疑似麻疹病例咽拭子标本进行麻疹病毒核酸检测,引进RT-PCR-RFLP方法对麻疹病毒核酸检测阳性咽拭子标本进行检测是否含有AflⅡ酶切位点(疫苗株病毒有,野病毒没有)鉴别疫苗相关麻疹病例.结果 麻疹病毒核酸检测阳性标本为9例,阳性率为2.25%;9例麻疹病毒核酸检测阳性标本RT-PCR-RFLP方法检测的结果为均未能被AflⅡ酶切开,为麻疹野病毒感染.结论成功引进和建立宜春市麻疹野病毒感染病例与疫苗株病毒引起的相关麻疹病例的RT-PCR-RFLP快速鉴别方法,并鉴别了2015年宜春市9例麻疹病例均由麻疹病毒野病毒感染引起.     

乙型肝炎病毒前C区及基本核心启动子变异检测方法的比较研究

目的 建立错配聚合酶链反应-限制性片段长度多态性（mPCR-RFLP）检测乙型肝炎病毒（HBV）前C区A1896、基本核心启动子（BCP）T1762/A1764双变异的方法,与直接测序法比较,评估其应用价值.方法 利用错配PCR的原理扩增HBV前C区长194 bp、C启动子区长184 bp的基因片段,扩增产物分别经限制性内切酶Bsu36I、BclI酶切,琼脂糖凝胶电泳,根据酶切图谱多态性,建立检测HBV前C A1896、BCP T1762/A1764双变异的方法,对127份HBsAg、HBV DNA阳性的HBV感染者血清进行分析,酶切同时测序.2份标本用克隆测序以验证酶切鉴定变异株、野株混合感染的准确性.结果 127份血清中125（98.42%）份能用酶切、121（95.21%）份能用测序分析HBV前CA1896、BCP T1762/A1764状况.酶切与测序均成功的119份血清中,16份为前C区A1896变异株,34份为BCP T1762/A1764双变异株,21份为前C区A1896、BCP T1762/A1764联合变异株,48份为前C区G1896、BCP A1762/G1764野株,酶切与测序的结果完全一致.1份酶切鉴定为前C区A1896、G1896混合感染标本的5个克隆子中,1个为前C区A1896变异株,另外4个为前C区G1896野株;另1份酶切鉴定为单纯前C区A1896变异标本的5个克隆子均为前C区A1896变异株,酶切分析结果与克隆测序结果完全相符.结论 与测序法相比,本方法较简便、特异性强,能区分野毒株、变异株混合感染,适合较大样本分析,可用于流行病学调查及临床筛查.     

Oncolytic measles viruses for cancer therapy

New strategies using biological agents are being developed to treat cancer. Live viruses are among these new agents. Virotherapy uses replication-competent viral vectors with strong oncolytic properties. With the use of molecular virology techniques, viruses have been genetically engineered to replicate selectively in tumour cells and are under preclinical and clinical investigation at present. Measles virus (MV) is being used for this purpose. Replication-competent attenuated Edmonston B measles vaccine strain (MV-Edm) is non-pathogenic and has potent antitumour activity against several human tumours. The virus is selectively oncolytic in tumour cells, eliciting extensive cell-to-cell fusion and ultimately leading to cell death. Therefore, MV-Edm is a safe and efficient means to kill tumour cells. Further improvements in existing MV vectors may increase tumour selectivity and oncolytic activity. This review discusses the discovery and development of replication-competent oncolytic MV for cancer therapy.     

Oncolytic measles viruses for cancer therapy

New strategies using biological agents are being developed to treat cancer. Live viruses are among these new agents. Virotherapy uses replication-competent viral vectors with strong oncolytic properties. With the use of molecular virology techniques, viruses have been genetically engineered to replicate selectively in tumour cells and are under preclinical and clinical investigation at present. Measles virus (MV) is being used for this purpose. Replication-competent attenuated Edmonston B measles vaccine strain (MV-Edm) is non-pathogenic and has potent antitumour activity against several human tumours. The virus is selectively oncolytic in tumour cells, eliciting extensive cell-to-cell fusion and ultimately leading to cell death. Therefore, MV-Edm is a safe and efficient means to kill tumour cells. Further improvements in existing MV vectors may increase tumour selectivity and oncolytic activity. This review discusses the discovery and development of replication-competent oncolytic MV for cancer therapy.     

Potential and clinical translation of oncolytic measles viruses

Introduction: Oncolytic viruses represent a novel treatment modality that is unencumbered by the standard resistance mechanisms limiting the therapeutic efficacy of conventional antineoplastic agents. Attenuated engineered measles virus strains derived from the Edmonston vaccine lineage have undergone extensive preclinical evaluation with significant antitumor activity observed in a broad range of preclinical tumoral models. These have laid the foundation for several clinical trials in both solid and hematologic malignancies, which have demonstrated safety, biologic activity and the ability to elicit antitumor immune responses.

Areas covered: This review examines the published preclinical data which supported the clinical translation of this therapeutic platform, reviews the available clinical trial data and expands on ongoing phase II testing. It also looks at approaches to optimize clinical applicability and offers future perspectives.

Expert opinion: Reverse genetic engineering has allowed the generation of oncolytic MV strains retargeted to increase viral tumor specificity, or armed with therapeutic and immunomodulatory genes in order to enhance anti-tumor efficacy. Continuous efforts focusing on exploring methods to overcome resistance pathways and determining optimal combinatorial strategies will facilitate further development of this encouraging antitumor strategy.     

A case study of measles vaccination for university students during the measles outbreak in Tokyo, Japan, 2007

In April 2007, seven students belonging to the same class at Teikyo University developed measles. To prevent the spread of infection, 27 of 106 students in the same class who had low anti-measles antibody titers as measured by hemagglutination inhibition (HI) assay were vaccinated. After the outbreak had subsided, the HI values were investigated in 103 students, and they answered questionnaires about their health condition during the period of the outbreak and their previous clinical histories of measles, including vaccination records. There was no new case of measles after introduction of the vaccination program. However, the HI titers of 42% of the students who were not vaccinated in this program were significantly elevated. Fever and catarrhal signs occurred in 7 of these students with pre-exposure titers of 8 or less. The post-exposure HI titers of 71% of students who were unaffected by measles and had high HI titers (>8) before the epidemic did not increase. These results suggested that people with low HI titers may become potential carriers of measles and that measurement of pre-exposure HI anti-measles antibody titer is a useful method for selection of candidates to undergo vaccination.     

2004年冬季北京患儿中低滴度甲3型流感病毒HA1基因特性分析

目的 分析2004年流感流行季节北京地区流感样病患儿患者分离的低滴度甲3型流感病毒血凝素（HA1）基因的特性。方法用2004年流感流行季节分离的22株低滴度甲3型流感病毒提取病毒RNA，经RT．PCR扩增得到HA1区基因片段。用生物信息软件分析HA1区基因特性。结果扩增的血凝素HA1区基因均为987bp。22株HA1氨基酸序列与当年的疫苗参考株比较，发现氨基酸变异，变异位点在3个抗原决定簇（A、B、D）和受体结合部位的位点，提示本流行季节的流感病毒变异较大，与世界卫生组织推荐2005年疫苗参考株比较，与南半球参考株有2个抗原决定簇（A、D）的氨基酸存在不同，与北半球参考株无明显差异。还发现1株变异，在高保守受体结合部位的底部98位氨基酸也发生了变异。结论2004年冬季流感流行株的变异倾向值得密切关注。     

Serum and CSF antibody levels to herpes simplex type 1, measles and rubella viruses in patients with schizophrenia.

Serum and CSF specimens from 12 schizophrenic patients and 10 non-psychiatric controls were tested for herpes simplex type 1 virus neutralizing antibody and for measles and rubella haemagglutination inhibiting antibodies. There were no significant differences in the distribution of virus antibody titres in serum or CSF specimens between the patients and the controls. The possible aetiological role of viruses or virus-like agents in schizophrenia and some methodological aspects are discussed.