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61.
《Vaccine》2021,39(41):6174-6181
Vaccinia virus has been used as a smallpox vaccine. Now that smallpox has been eradicated, the vaccinia virus is expected to be used as a bioterrorism countermeasure and a recombinant vaccine vector for other infectious diseases, such as viral hemorrhagic fevers. Many vaccinia virus strains were used as smallpox vaccines in the smallpox eradication campaign coordinated by the World Health Organization. These strains can be classified into generations, according to the history of improving production methods and efforts to reduce the adverse reactions. Significantly, the third-generation of smallpox vaccine strains, which include modified vaccinia Ankara (MVA) and LC16m8, are currently popular as recombinant vaccine vectors due to their well-balanced safety and immunogenicity profiles. The present review firstly focuses on the characteristics of the smallpox vaccine generations. The historical background of the development of the third-generation smallpox vaccine strains is detailed, along with the history of the transition of the vaccinia virus generation used as vectors for hemorrhagic fever vaccines to the third generation. Among the vaccinia viruses, MVA is currently the most commonly used vector for developing hemorrhagic fever vaccines, including dengue fever, yellow fever, Ebola viral disease, Lassa fever, Rift Valley fever, and Crimean-Congo hemorrhagic fever. LC16m8 is a vaccine candidate for severe fever with thrombocytopenia syndrome. The current status and recent advances in the development of these hemorrhagic fever vaccines using third-generation vaccinia strains are discussed. 相似文献
62.
《Vaccine》2022,40(20):2833-2840
The animal-human interface has played a central role in advances made in vaccinology for the past two centuries. Many traditional veterinary vaccines were developed by growing, attenuating, inactivating and fractioning the pathogen of interest. While such approaches have been very successful, we have reached a point where they have largely been exhausted and alternative approaches are required. Furthermore, although subunit vaccines have enhanced safety profiles and created opportunities for combined discrimination between vaccinated and infected animal (DIVA) approaches, their functionality has largely been limited to diseases that can be controlled by humoral immunity until very recently. We now have a new generation of adjuvants and delivery systems that can elicit CD4 + T cells and/or CD8 + T cell responses in addition to high-titre antibody responses. We review the current vaccine platform technologies, describe their roles in veterinary vaccinology and discuss how knowledge of their mode of action allows informed decisions on their deployment with wider benefits for One Health. 相似文献
63.
病毒性肝炎患者血清IL-6和T细胞亚群的关系 总被引:5,自引:0,他引:5
采用MTT比色法和抗体致敏的红细胞花环试验(间接法) 检测了91例病毒性肝炎患者血清IL-6和T细胞亚群。 结果显示,病毒性肝炎患者血清IL-6活性均明显高于正常对照组(P<0.01),以重型肝炎为最高;且与肝细胞损害程度呈正比(P<0.01);CD4~+细胞、CD4+/CD8~+均明显降低,与血清IL-6呈负相关;CO8~+细胞明显增高,与血清IL-6呈正相关(P<0.01)。表明,血清IL-6与机体细胞免疫功能密切相关,二者互为因果,共同参与病毒性肝炎的免疫病理损害,可作为判断病情和预后及免疫调节治疗的监测指标。 相似文献
64.
北京地区病毒性脑炎患者病原体的分离和初步鉴定 总被引:2,自引:1,他引:2
1991年夏秋季,我们从41例北京儿童医院临床诊断为病毒性脑炎(非乙脑)患者的75份急性期血和/或脑脊液中分离到33株病毒。对其中12株进行电镜观察,电镜下均见大小相同的球形病毒颗粒,毒粒的直径约为44.78±1.35um,无囊膜,具双层蛋白外壳,视野内多见空心颗粒。超薄切片显示病毒在感染细胞的胞浆内发生,直径约为47.6±2.3um。正常细胞中未见病毒颗粒。对其中3株病毒进行理化性状分析,多次试验均显示该病毒抵抗5'-碘脱氧尿苷,抵抗乙醚,耐酸,能在地鼠肾BHK-21和白纹伊蚊C6/36细胞上增殖并出现细胞病变。该病毒与本室制备的披膜病毒科甲组、乙脑病毒和布尼亚病毒科的组特异性免疫腹水均不反应。脑内接种3日龄乳小白鼠可引起不规律的发病和死亡。上述结果表明,该病毒是一类45um左右、无囊膜、耐酸的RNA病毒。 相似文献
65.
小儿喉乳头状瘤HPV-DNA及体液免疫检测 总被引:6,自引:1,他引:5
目的:探讨小儿喉乳头状瘤(JLP)人乳头瘤病毒(HPV)感染途径及发病机理。方法:采用PCR及PCR产物斑点杂交技术检测JLP组织HPV-DNA;散射免疫比浊法测定血清Ig及补体C3。结果:JLP组织HPV总感染率为95%(19/20),其中HPV。型为55%(11/20),HPV11为30%(6/20),HPV6+11型为10%(2/20);JLP患者血清IgG、IgA、IgM、C3值正常,对照 相似文献
66.
67.
目的 :观察推拿在治疗婴儿轮状病毒性肠炎中的疗效。方法 :将72例确诊患儿随机分为二组 ,两组患儿一般治疗相同 ,治疗组加推拿疗法。结果 :治疗组症状消失时间明显缩短 ,止泻时间治疗组为(38 5±15 5)h ,对照组(50 2±18 5)h ,差异有显著性意义(P<0 01)。治疗组总有效率为95% ,对照组为80 %(P<0 05)。结论 :推拿治疗婴儿轮状病毒性肠炎安全、有效、简便、价廉 相似文献
68.
《Clinical microbiology and infection》2023,29(2):171-181
BackgroundEbola virus disease (EVD) is a dangerous condition that can cause an epidemic. Several rapid diagnostic tests (RDTs) have been developed to diagnose EVD. These RDTs promise to be quicker and easier to use than the current reference standard diagnostic test, PCR.ObjectivesTo assess the diagnostic accuracy of RDTs for EVD.MethodsA systematic review of diagnostic accuracy studies.Data sourcesThe following bibliographic databases were searched from inception to present: MEDLINE (Ovid), Embase, Global Health, Cochrane Central Register of Controlled Trials, WHO Global Index Medicus database, Web of Science, PROSPERO register of Systematic Reviews, and Clinical Trials.Gov.Study eligibility criteriaDiagnostic accuracy studies.ParticipantsPatients presenting to the Ebola treatment units with symptoms of EVD.InterventionsRDTs; reference standard, RT-PCR.Assessment of risk of biasQuality Assessment of Diagnostic Accuracy Studies-2 tool.Methods of data synthesisSummary estimates of diagnostic accuracy study were produced for each device type. Subgroup analyses were performed for RDT type and specimen material. A sensitivity analysis was performed to assess the effect of trial design and bias.ResultsWe included 15 diagnostic accuracy studies. The summary estimate of sensitivity for lateral flow assays was 86.1% (95% CI, 86–86.2%), with specificity of 97% (95% CI, 96.1–97.9%). The summary estimate for rapid PCR devices was sensitivity of 96.2% (95% CI, 95.3–97.9%), with a specificity of 96.8% (95% CI, 95.3–97.9%). Pre-specified subgroup analyses demonstrated that RDTs were effective on a range of specimen material. Overall, the risk of bias throughout the included studies was low, but it was high in patient selection and uncertain in the flow and timing domains.ConclusionsRDTs possess both high sensitivity and specificity compared with RT-PCR among symptomatic patients presenting to the Ebola treatment units. Our findings support the use of RDTs as a ‘rule in’ test to expedite treatment and vaccination. 相似文献
69.
胎儿先天性心脏病筛查方法的研究 总被引:6,自引:0,他引:6
为尽早确诊胎儿先天性心脏病(简称先心病),对200例胎儿进行B超心动图检查,发现心脏异常36例(18%),其中先心病26例(13%)。测定有高危因素的103例孕母血清风疹病毒抗体IgM,10例阳性(9.7%),其中7例胎儿有先心病(70%),其灵敏度为70%,特异度为92.3%,可做为胎儿先心病的筛查方法。两项检查合用,可提高胎儿先心病的诊断水平。同时提示胎儿超声心动图检查中增加卵圆孔直径和血流的评定可作为房间隔缺损的诊断标准。 相似文献
70.
目的:构建丙型肝炎病毒(HCV)E2和乙型肝炎病毒(HBV)preS融合蛋白的真核表达载体.方法:用PCR方法扩增HBV preS和HCV E2蛋白基因,并将二者克隆到真核表达载体pcDNA3中,用脂质体转染试剂将其转入COS7细胞,通过免疫荧光检测细胞瞬时表达的融合蛋白.结果:E2-preS融合蛋白基因包括了全长的HBV preS和HCV E2蛋白基因,嵌合基因长度约1.6 kb.表达载体在COS7细胞表达出了E2-preS融合蛋白.结论:构建的E2-preS融合蛋白表达载体能在哺乳动物细胞中表达融合蛋白,为获得真核表达的融合蛋白及研究此蛋白的免疫原性打下基础. 相似文献