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71.
SARS冠状病毒N蛋白的原核表达及活性测定 总被引:1,自引:1,他引:0
目的克隆编码严重急性呼吸综合征冠状病毒(sARSCoV)N蛋白的DNA,构建原核表达质粒pGEX-2T/N,并诱导表达。方法采用RT-PCR方法从病毒培养液中获得N基因片段。将N蛋白基因序列定向插入原核表达载体pGEX-2T中,在大肠杆菌中表达融合蛋白。用表达产物与抗SARS-CoV抗体阳性血清做Western blot。结果获得N基因片段;GST-N融合蛋白以可溶形式表达;Western blot检测表明,其与抗SARS-CoV抗体阳性血清的反应呈阳性。结论成功地构建原核表达质粒pGEX-2T/N,并表达GST-N融合蛋白,为下一步的研究奠定了基础。 相似文献
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目的 测定SARS冠状病毒GD322株S2基因序列并对SARS-CoVS2基因进行系统进化树分析。方法用RT-PCR法从SARS-CoV GD322株基因组中扩增S2基因片段并克隆至pGEM—T载体,转化大肠杆菌DH5a株后测序。利用Lasergene、ClustalX、DNAman和Treeview等软件,将基因序列翻译成氨基酸序列后,与早、中、晚期各地暴发的SARS-CoVS2蛋白序列进行比对,构建系统进化树,并在Internet网数据库中对S2蛋白氨基酸序列进行T细胞抗原表位预测。结果随着SARS-CoV的传播流行,S2基因趋于稳定,晚期的SARS-CoVS2基因的同源性达到99.9%。T细胞抗原表位预测发现。SARS-CoVS2蛋白第57位氨基酸突变对T细胞抗原表位有影响。结论SARS流行过程中SARS-CoVS2基因较为稳定,S2蛋白57位氨基酸的突变可影响病毒T细胞抗原表位。 相似文献
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目的构建含SARS病毒S蛋白编码基因片段的表达载体,并将其置于Vero细胞中表达。方法设计1对PCR引物,在其下游引入Flag序列,通过PCR方法从质粒pGEX-6P-1-SARS-S中扩增出S蛋白编码基因,PCR产物经酶切后,插入表达载体pcDNA3.1(+)中,构建重组表达质粒pcDNA3.1(+)-SARS-S。重组质粒经酶切鉴定及核苷酸序列测定和分析后转染Vero细胞,用抗Flag单克隆抗体通过Western blot检测S蛋白片段在Vero细胞中的表达。结果酶切鉴定及核苷酸序列测定和分析示重组质粒构建完全正确;Western blot证实重组S蛋白片段能够在Vero细胞表达。结论融合Flag序列的SARS病毒S蛋白片段在Vero细胞中获得了正确表达。 相似文献
76.
Lukas Hobohm Ingo Sagoschen Stefano Barco Irene Schmidtmann Christine Espinola-Klein Stavros Konstantinides Thomas Münzel Karsten Keller 《Viruses》2022,14(2)
Unselected data of nationwide studies of hospitalized patients with COVID-19 are still sparse, but these data are of outstanding interest to avoid exceeding hospital capacities and overloading national healthcare systems. Thus, we sought to analyze seasonal/regional trends, predictors of in-hospital case-fatality, and mechanical ventilation (MV) in patients with COVID-19 in Germany. We used the German nationwide inpatient samples to analyze all hospitalized patients with a confirmed COVID-19 diagnosis in Germany between 1 January and 31 December in 2020. We analyzed data of 176,137 hospitalizations of patients with confirmed COVID-19-infection. Among those, 31,607 (17.9%) died, whereby in-hospital case-fatality grew exponentially with age. Overall, age ≥ 70 years (OR 5.91, 95%CI 5.70–6.13, p < 0.001), pneumonia (OR 4.58, 95%CI 4.42–4.74, p < 0.001) and acute respiratory distress syndrome (OR 8.51, 95%CI 8.12–8.92, p < 0.001) were strong predictors of in-hospital death. Most COVID-19 patients were treated in hospitals in urban areas (n = 92,971) associated with the lowest case-fatality (17.5%), as compared to hospitals in suburban (18.3%) or rural areas (18.8%). MV demand was highest in November/December 2020 (32.3%, 20.3%) in patients between the 6th and 8th age decade. In the first age decade, 78 of 1861 children (4.2%) with COVID-19-infection were treated with MV, and five of them died (0.3%). The results of our study indicate seasonal and regional variations concerning the number of COVID-19 patients, necessity of MV, and case fatality in Germany. These findings may help to ensure the flexible allocation of intensive care (human) resources, which is essential for managing enormous societal challenges worldwide to avoid overloaded regional healthcare systems. 相似文献
77.
《Neurología (Barcelona, Spain)》2020,35(3):170-175
IntroductionThere is growing evidence that SARS-CoV-2 can gain access to the central nervous system (CNS). We revise the literature on coronavirus infection of the CNS associated with neurological diseases.DevelopmentNeurological symptoms were rarely reported in the SARS-CoV and MERS-CoV epidemics, although isolated cases were described. There are also reports of cases of neurological symptoms associated with CoV-OC43 and CoV-229E infection. The presence of neurological lesions, especially demyelinating lesions in the mouse hepatitis virus model, may explain the mechanisms by which coronaviruses enter the CNS, particularly those related with the immune response. This may explain the presence of coronavirus in patients with multiple sclerosis. We review the specific characteristics of SARS-CoV-2 and address the question of whether the high number of cases may be associated with greater CNS involvement.ConclusionAlthough neurological symptoms are not frequent in coronavirus epidemics, the high number of patients with SARS-CoV-2 infection may explain the presence of the virus in the CNS and increase the likelihood of early- or delayed-onset neurological symptoms. Follow-up of patients affected by the SARS-CoV-2 epidemic should include careful assessment of the CNS. 相似文献
78.
Giorgio Bogani MD PhD Jvan Casarin MD Ciro Pinelli MD Violante Di Donato MD PhD Sara Bosio MD Simona Ruisi MD Claudia Brusadelli MD Rocco Guerrisi MD Giuseppe Sarpietro MD Antonino Ditto MD Fabio Ghezzi MD Francesco Raspagliesi MD 《Journal of surgical oncology》2020,122(2):122-123
At the beginning of 2020, coronavirus disease 2019 (COVID-19) spreads worldwide. Patients with ovarian cancer should be considered at high-risk of developing severe morbidity related to COVID-19. Most of them are diagnosed in advanced stages of disease, and they are fragile. Here, we evaluated the major impact of COVID-19 on patients with ovarian cancer, discussing the effect of the outbreak on medical and surgical treatment. 相似文献
79.
《Viruses》2020,12(12)
Multiple epicenters of the SARS-CoV-2 pandemic have emerged since the first pneumonia cases in Wuhan, China, such as Italy, USA, and Brazil. Brazil is the third-most affected country worldwide, but genomic sequences of SARS-CoV-2 strains are mostly restricted to states from the Southeast region. Pernambuco state, located in the Northeast region, is the sixth most affected Brazilian state, but very few genomic sequences from the strains circulating in this region are available. We sequenced 101 strains of SARS-CoV-2 from patients presenting Covid-19 symptoms that reside in Pernambuco. Phylogenetic reconstructions revealed that all genomes belong to the B lineage and most of the samples (88%) were classified as lineage B.1.1. We detected multiple viral introductions from abroad (likely from Europe) as well as six local B.1.1 clades composed by Pernambuco only strains. Local clades comprise sequences from the capital city (Recife) and other country-side cities, corroborating the community spread between different municipalities of the state. These findings demonstrate that different from Southeastern Brazilian states where the epidemics were majorly driven by one dominant lineage (B.1.1.28 or B.1.1.33), the early epidemic phase at the Pernambuco state was driven by multiple B.1.1 lineages seeded through both national and international traveling. 相似文献
80.
目的通过对动物从业人员以及其它健康人群感染SARS-CoV的血清学研究,揭示人群中SARS-CoV抗体水平,探讨动物作为传染源的传播途径.方法随机选取无SARS临床症状的健康动物从业人员以及其它健康人员等545人作为调查对象,使用统一调查表对调查对象进行个案调查,同时采集调查对象的血清,用ELISA法检测SARS-CoV抗体.结果共检测各种人群血样545份,其中动物从业人员血样269份,SARS-CoV抗体阳性率为8.18%;健康人群血样276份,阳性率为1.09%,动物从业人员SARS-CoV抗体阳性率和非从业人员SARS-CoV抗体阳性率比较有显著性差异.结论动物从业人员SARS-CoV抗体阳性率显著高于非从业人员,支持SARS-CoV源于野生动物的假设. 相似文献