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1.
《Vaccine》2021,39(14):1933-1942
The genetic and antigenic drift associated with the high pathogenicity avian influenza (HPAI) viruses of Goose/Guangdong (Gs/GD) lineage and the emergence of vaccine-resistant field viruses underscores the need for a broadly protective H5 influenza A vaccine. Here, we tested experimental vector herpesvirus of turkey (vHVT)-H5 vaccines containing either wild-type clade 2.3.4.4A-derived H5 inserts or computationally optimized broadly reactive antigen (COBRA) inserts with challenge by homologous and genetically divergent H5 HPAI Gs/GD lineage viruses in chickens. Direct assessment of protection was confirmed for all the tested constructs, which provided clinical protection against the homologous and heterologous H5 HPAI Gs/GD challenge viruses and significantly decreased oropharyngeal shedding titers compared to the sham vaccine. The cross reactivity was assessed by hemagglutinin inhibition (HI) and focus reduction assay against a panel of phylogenetically and antigenically diverse H5 strains. The COBRA-derived H5 inserts elicited antibody responses against antigenically diverse strains, while the wild-type-derived H5 vaccines elicited protection mostly against close antigenically related clades 2.3.4.4A and 2.3.4.4D viruses. In conclusion, the HVT vector, a widely used replicating vaccine platform in poultry, with H5 insert provides clinical protection and significant reduction of viral shedding against homologous and heterologous challenge. In addition, the COBRA-derived inserts have the potential to be used against antigenically distinct co-circulating viruses and future drift variants.  相似文献   
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The 2019 coronavirus pandemic, which started in Wuhan, China, spread around the globe with dramatic and lethal effects. From the initial Chinese epicenter, the European diaspora taxed the resources of several countries and especially those of Italy, which was forced into a complete social and economic shutdown. Infection by droplets contaminating hands and surfaces represents the main vehicle of diffusion of the virus. The common and strong efforts to contain the pandemic have relevant effects on the management of samples from histopathology laboratories. The current commentary reports and focuses on the protocols and guidelines in use at a large tertiary Italian hospital that accordingly are proposed for adoption in Italian laboratories as a potential model for national guidelines for the coronavirus emergency.  相似文献   
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《Vaccine》2020,38(6):1526-1534
Despite decades of vaccination, surveillance, and biosecurity measures, H5N2 low pathogenicity avian influenza (LPAI) virus infections continue in Mexico and neighboring countries. One explanation for tenacity of H5N2 LPAI in Mexico is the antigenic divergence of circulating field viruses compared to licensed vaccines due to antigenic drift. Our phylogenetic analysis indicates that the H5N2 LPAI viruses circulating in Mexico and neighboring countries since 1994 have undergone antigenic drift away from vaccine seed strains. Here we evaluated the efficacy of a new recombinant fowlpox virus vector containing an updated H5 insert (rFPV-H5/2016), more relevant to the current strains circulating in Mexico. We tested the vaccine efficacy against a closely related subcluster 4 Mexican H5N2 LPAI (2010 H5/LP) virus and the historic H5N2 HPAI (1995 H5/HP) virus in White Leghorn chickens. The rFPV-H5/2016 vaccine provided hemagglutinin inhibition (HI) titers pre-challenge against viral antigens from both challenge viruses in almost 100% of the immunized birds, with no differences in number of birds seroconverting or HI titers among all tested doses (1.5, 2.0, and 3.1 log10 mean tissue culture infectious doses/bird). The vaccine conferred 100% clinical protection and a significant decrease in oral and cloacal virus shedding from 1995 H5/HP virus challenged birds when compared to the sham controls at all tested doses. Virus shedding titers from vaccinated 2010 H5/LP virus challenged birds significantly decreased compared to sham birds especially at earlier time points. Our results confirm the efficacy of the new rFPV-H5/2016 against antigenic drift of LPAI virus in Mexico and suggest that this vaccine would be a good candidate, likely as a primer in a prime-boost vaccination program.  相似文献   
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目的评价新型纳米羟基磷灰石/聚酰胺66融合器(nano-hydroxyapatite/polyamide66Cage,n—HA/PA66Cage)植人人体内可能引起的全身毒性反应及对人体局部组织的影响。方法2012年2月至2012年4月将n—FLA/PA66Cage通过腰椎后路经椎间孔进行腰椎椎体融合植入20例患者体内,通过对研究对象检查术前、术后4d、术后2个月等3个时期的血压、脉搏、体温、免疫球蛋白A、G、M、补体C3、C4、谷丙转氨酶、谷草转氨酶、肌酐、尿素、白细胞、红细胞、血红蛋白、血小板、C反应蛋白、血沉、局部反应等指标。结果n—HA/PA66Cage植人人体后,除了术后4d白细胞、红细胞、血红蛋白、血小板等血常规、C反应蛋白、血沉等检查与术前相比,存在统计学差异(P〈0.05);在不同时相,其他检查结果之间无统计学意义(P〉0.05)。结论新型n—HA/PA66Cage具有良好的生物安全性。  相似文献   
6.
Since 2012, H7N3 highly pathogenic avian influenza (HPAI) has produced negative economic and animal welfare impacts on poultry in central Mexico. In the present study, chickens were vaccinated with two different recombinant fowlpox virus vaccines (rFPV-H7/3002 with 2015 H7 hemagglutinin [HA] gene insert, and rFPV-H7/2155 with 2002 H7 HA gene insert), and were then challenged three weeks later with H7N3 HPAI virus (A/chicken/Jalisco/CPA-37905/2015). The rFPV-H7/3002 vaccine conferred 100% protection against mortality and morbidity, and significantly reduced virus shed titers from the respiratory and gastrointestinal tracts. In contrast, 100% of sham and rFPV-H7/2155 vaccinated birds shed virus at higher titers and died within 4?days. Pre- (15/20) and post- (20/20) challenge serum of birds vaccinated with rFPV-H7/3002 had antibodies detectable by hemagglutination inhibition (HI) assay using challenge virus antigen. However, only a few birds (3/20) in the rFPV-H7/2155 vaccinated group had antibodies that reacted against the challenge strain but all birds had antibodies that reacted against the homologous vaccine antigen (A/turkey/Virginia/SEP-66/2002) (20/20). One possible explanation for differences in vaccines efficacy is the antigenic drift between circulating viruses and vaccines. Molecular analysis demonstrated that the Mexican H7N3 strains have continued to rapidly evolve since 2012. In addition, we identified in silico three potential new N-glycosylation sites on the globular head of the H7 HA of A/chicken/Jalisco/CPA-37905/2015 challenge virus, which were absent in 2012 H7N3 outbreak virus. Our results suggested that mutations in the HA antigenic sites including increased glycosylation sites, accumulated in the new circulating Mexican H7 HPAIV strains, altered the recognition of neutralizing antibodies from the older vaccine strain rFPV-H7/2155. Therefore, the protective efficacy of novel rFPV-H7/3002 against recent outbreak Mexican H7N3 HPAIV confirms the importance of frequent updating of vaccines seed strains for long-term effective control of H7 HPAI virus.  相似文献   
7.
实验室的安全教育是科研工作者必不可少的一部分,医学生作为特殊的科研人员,因为肩负着救死扶伤的使命,导致他们实验室的工作经验相对较少,不重视实验室的安全教育,成为生物安全问题的易发人群。本文首先阐述医学生实验室安全意识亟待提高的现状,进而从开展生物安全教育、注重实验室管理和实验室技术人员培训、开展实验室生物安全课程及采用网络技术与射频识别(RFID)技术相结合的生物安全监督系统等方面加强医学生实验室安全意识,以期减少医学生发生生物安全事故。  相似文献   
8.
利用疫苗对养殖鱼类进行疾病预防正得到逐步应用,而减毒活疫苗通过浸泡方式也能使鱼体获得较高的免疫保护力。利用模式动物斑马鱼对鳗弧菌减毒活疫苗MVAV6203的生物安全性进行了评价。首先进行了疫苗对斑马鱼毒性实验,每条鱼注射免疫的半致死量为9.26×104 CFU;其次分析了鳗弧菌在水体中的存活情况,菌体浓度在1.0×106 CFU/mL条件下,10 d后水体基本检测不到鳗弧菌;最后考察了其在鱼体内的存活情况,注射或浸泡免疫3 d后,鱼体组织匀浆物未检测到该菌,表明鳗弧菌减毒活疫苗具有较好的生物安全性。  相似文献   
9.
建立药品检测机构生物安全柜管理方法。从生物安全柜的选择、检测、使用年限、注意事项、维修维护和档案6个方面介绍生物安全柜的管理要点,并从检测数据分析建议使用年限7年。生物安全柜的规范管理,是实验室人员安全数据准确的前提和保障。  相似文献   
10.
目的了解新型冠状病毒肺炎疫情下重庆市医疗机构临床实验室生物安全现状。方法于2020年2月8-15日,对重庆市42家新型冠状病毒肺炎定点救治医院临床实验室发放问卷调查,调查内容包括实验室基本情况、实验室生物安全设施设备配置、实验室个人防护用品配置、实验室未开展新型冠状病毒核酸检测原因、实验室生物安全培训情况等。结果在规定时间内收到26家实验室有效回报,26家定点医疗机构中二级和三级医疗机构各占50.0%。所有实验室均为已备案的生物安全二级实验室;无门禁装置实验室1家(3.8%),无自动可关闭门实验室2家(7.7%),无负压条件实验室22家(84.6%);自然通风实验室15家(57.7%);4家(13.4%)实验室安全设备未年检;6家(23.1%)实验室没有防护服储备。10家未开展新型冠状病毒核酸检测的实验室中有7家(70.0%)原因为三级生物安全防护用品缺乏。26家实验室均及时组织了人员培训,1家(3.8%)实验室组织了针对性的操作演练。结论实验室应加强安全设施设备的投入和监管,加大应急防护物资的储备,建立健全有效的生物安全培训体系,进一步提高临床验室应对新发、突发传染病的生物安全管理能力。  相似文献   
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