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36 个结果
  • 简介:AbstractSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve, generating new variants that pose a threat to global health; therefore, it is imperative to obtain safe and broad-spectrum antivirals against SARS-CoV-2 and its variants. To this end, we screened compounds for their ability to inhibit viral entry, which is a critical step in virus infection. Twenty compounds that have been previously reported to inhibit SARS-CoV-2 replication were tested by using pseudoviruses containing the spike protein from the original strain (SARS-CoV-2-WH01). The cytotoxicity of these compounds was determined. Furthermore, we identified six compounds with strong antagonistic activity against the WH01 pseudovirus, and low cytotoxicity was identified. These compounds were then evaluated for their efficacy against pseudoviruses expressing the spike protein from B.1.617.2 (Delta) and B.1.1.529 (Omicron), the two most prevalent circulating strains. These assays demonstrated that two phenothiazine compounds, trifluoperazine 2HCl and thioridazine HCl, inhibit the infection of Delta and Omicron pseudoviruses. Finally, we discovered that these two compounds were highly effective against authentic SARS-CoV-2 viruses, including the WH01, Delta, and Omicron strains. Our study identified potential broad-spectrum SARS-CoV-2 inhibitors and provided insights into the development of novel therapeutics.

  • 标签: SARS-CoV-2 Delta variant Omicron variant Trifluoperazine 2HCl Thioridazine HCl Antiviral therapy
  • 简介:AbstractOmicron (B.1.1.529), the fifth variant of concern (VOC) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was firstly identified in November 2021 in South Africa. Omicron contains far more genome mutations than any other VOCs ever found, raising significant concerns about its increased transmissibility and immune evasion. Here, we report the importation of the Omicron variant into Beijing, China, in December 2021. Full-length genome sequences of five imported strains were obtained, with their genetic features characterized. Each strain contained 57 to 61 nucleotide substitutions, 39 deletions, and 9 insertions in the genome. Thirty to thirty-two amino acid changes were found in the spike proteins of the five strains. The phylogenetic tree constructed by the maximum likelihood method showed that all five imported genomes belonged to Omicron (BA.1) (alias of B.1.1.529.1), which is leading to the current surge of coronavirus disease 2019 (COVID-19) cases worldwide. The globally increased COVID-19 cases driven by the Omicron variant pose a significant challenge to disease prevention and control in China. Continuous viral genetic surveillance and increased testing among international travellers are required to contain this highly contagious variant.

  • 标签: COVID-19 SARS-CoV-2 Omicron variant Genomic characteristics
  • 简介:AbstractAt present, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread worldwide, which has emerged multiple variants and brought a threat to global public health. To analyze the genomic characteristics and variations of SARS-CoV-2 imported into Beijing, we collected the respiratory tract specimens of 112 cases of coronavirus disease 2019 (COVID-19) from January to September 2021 in Beijing, China, including 40 local cases and 72 imported cases. The whole-genome sequences of the viruses were sequenced by the next-generation sequencing method. Variant markers and phylogenic features of SARS-CoV-2 were analyzed. Our results showed that in all 112 sequences, the mutations were concentrated in spike protein. D614G was found in all sequences, and mutations including L452R, T478K, P681R/H, and D950N in some cases. Furthermore, 112 sequences belonged to 23 lineages by phylogenetic analysis. B.1.1.7 (Alpha) and B.1.617.2 (Delta) lineages were dominant. Our study drew a variation image of SARS-CoV-2 and could help evaluate the potential risk of COVID-19 for pandemic preparedness and response.

  • 标签: Severe acute respiratory syndrome coronavirus 2 Variation Genome Phylogenetic analysis
  • 简介:摘要新型冠状病毒肺炎疫情在世界范围肆虐,给全球公共卫生事业带来了极大冲击。本文从严重急性呼吸综合征冠状病毒2(SARS-CoV-2)引起的固有免疫应答、体液免疫应答、细胞免疫应答、免疫逃避与交叉免疫五方面对现有研究进行综述,希望通过阐述免疫机制中的作用靶点,为SARS-CoV-2的治疗与预防贡献新思路。

  • 标签: 新型冠状病毒 适应性免疫 免疫逃避 交叉免疫
  • 简介:AbstractArtificial intelligence (AI) has proven time and time again to be a game-changer innovation in every walk of life, including medicine. Introduced by Dr. Gunn in 1976 to accurately diagnose acute abdominal pain and list potential differentials, AI has since come a long way. In particular, AI has been aiding in radiological diagnoses with good sensitivity and specificity by using machine learning algorithms. With the coronavirus disease 2019 pandemic, AI has proven to be more than just a tool to facilitate healthcare workers in decision making and limiting physician-patient contact during the pandemic. It has guided governments and key policymakers in formulating and implementing laws, such as lockdowns and travel restrictions, to curb the spread of this viral disease. This has been made possible by the use of social media to map severe acute respiratory syndrome coronavirus 2 hotspots, laying the basis of the "smart lockdown" strategy that has been adopted globally. However, these benefits might be accompanied with concerns regarding privacy and unconsented surveillance, necessitating authorities to develop sincere and ethical government–public relations.

  • 标签: Artificial intelligence COVID-19 Machine learning
  • 简介:AbstractThe recently emerged Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has quickly spread around the world. Although many consensus mutations of the Omicron variant have been recognized, little is known about its genetic variation during its transmission in the population. Here, we comprehensively analyzed the genetic differentiation and diversity of the Omicron variant during its early outbreak. We found that Omicron achieved more structural variations, especially deletions, on the SARS-CoV-2 genome than the other four variants of concern (Alpha, Beta, Gamma, and Delta) in the same timescale. In addition, the Omicron variant acquired, except for 50 consensus mutations, seven great new non-synonymous nucleotide substitutions during its spread. Three of them are on the S protein, including S_A701V, S_L1081V, and S_R346K, which belong to the receptor-binding domain (RBD). The Omicron BA.1 branch could be divided into five divergent groups spreading across different countries and regions based on these seven novel mutations. Furthermore, we found that the Omicron variant possesses more mutations related to a faster transmission rate than the other SARS-CoV-2 variants by assessing the relationship between the genetic diversity and transmission rate. The findings indicated that more attention should be paid to the significant genetic differentiation and diversity of the Omicron variant for better disease prevention and control.

  • 标签: SARS-CoV-2 Omicron Genetic diversity
  • 简介:AbstractSince its first discovery, the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evoked another wave of infection and caused global concern and panic. Moreover, although the data are still limited, Omicron showed highly concerning characteristics, including higher transmissibility, extensive immune escape and potentially altered host range. We interpreted these characteristics based on currently available data and outlined some urgent questions, calling for a more comprehensive investigation.

  • 标签: SARS-CoV-2 Omicron strain Immune escape Interspecies transmission
  • 简介:AbstractThe pandemic of coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to major public health challenges globally. The increasing viral lineages identified indicate that the SARS-CoV-2 genome is evolving at a rapid rate. Viral genomic mutations may cause antigenic drift or shift, which are important ways by which SARS-CoV-2 escapes the human immune system and changes its transmissibility and virulence. Herein, we summarize the functional mutations in SARS-CoV-2 genomes to characterize its adaptive evolution to inform the development of vaccination, treatment as well as control and intervention measures.

  • 标签: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Mutation Variants of concern Variants of interest Adaptive evolution
  • 简介:摘要严重急性呼吸系统综合症冠状病毒2(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)感染造成的新型冠状病毒肺炎(coronavirus disease 2019,COVID-19)是人类本世纪来面临的威胁最大的传染病之一。目前,全球范围内有4类疫苗已经获批上市或授权紧急使用—灭活疫苗、mRNA疫苗、腺病毒载体疫苗和重组蛋白疫苗。随着COVID-19大流行的持续,已进行全程免疫人群的抗体水平逐渐降低,加强免疫是必要的措施,而序贯免疫策略似乎是一种更好的疫苗接种策略。本文将对四类不同技术路线疫苗在序贯免疫中的研究进行综述。

  • 标签: 新型冠状病毒 新型冠状病毒肺炎 序贯免疫 疫苗
  • 简介:摘要严重急性呼吸综合征冠状病毒2 (severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)感染导致的新型冠状病毒肺炎(coronavirus disease 2019,COVID-19)引发全球大流行。HIV感染者/艾滋病患者是一个特殊人群,由于其免疫系统受损及各种并发症,对SARS-CoV-2的感染风险、疾病严重程度和预后等产生重要影响。本文对HIV-1/SARS-CoV-2合并感染的流行病学特点、临床特征和转归等进行综述。

  • 标签: 1型艾滋病病毒 严重急性呼吸综合征冠状病毒2 新型冠状病毒肺炎 合并感染
  • 简介:摘要目的分析新型冠状病毒在不同食品和加工材料表面存活规律,为制定预防病毒通过食品和加工材料传播的防控措施和风险评估提供参考。方法将病毒培养物接种至常见进口食品和加工材料表面,使用荧光定量PCR方法测定在不同温度和时间条件下样本表面病毒核酸载量;使用半数组织培养感染剂量实验测定病毒滴度,观察病毒存活时间。使用线性回归模型计算病毒半衰期。结果食品和加工材料表面病毒核酸载量随时间下降,且温度越高病毒核酸载量下降越快。不同种类食品和加工材料表面病毒存活时间不同,室温条件下,猪肉和车厘子表面病毒存活24 h;其次为带鱼和鲜橙表面。加工材料表面病毒存活时间均较短,小于24 h。4 ℃条件下,病毒在猪肉表面至少存活1周,其次为车厘子和带鱼。-20 ℃条件下,病毒在猪肉和塑料包装表面的活性下降缓慢,8周后病毒滴度仍然较高,而在带鱼和纸板表面的活性下降明显。结论不同食品和加工材料表面的病毒核酸存续时间和存活规律不同,且温度越低病毒存活时间越长,应根据食品、加工材料类型,以及生产环境条件制定针对性预防和消毒措施。

  • 标签: 新型冠状病毒 食品 加工材料 表面 病毒活性
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  • 简介:AbstractThe coronavirus disease 2019 (COVID-19) is still causing a wide range of infections and deaths due to the high variability of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therefore, it is necessary to establish a reliable and convenient pseudovirus-based neutralization assay to develop drug targeted variants of SARS-CoV-2. Based on the HIV-1 backbone, we generated a high titer luciferase (Luc)-expressing pseudovirus packaging system. Three dominant S mutant substitution pseudovirus were also established and identified compared to wide type in hACE2-overexpressing HEK-293T cells (293T-ACE2 cells). Compared to serine protease inhibitor camostat mesylate, the cysteine protease inhibitor E-64d could significantly block all SARS-CoV-2 mutant S pseudovirus infection in 293T-ACE2 cells. Furthermore, the neutralization ability of two antibodies targeted receptor-binding domain (RBD) of SARS-CoV-2 spike protein (S) was evaluated, which showed different inhibition dose-effect curves among four types of S pseudovirus. Overall, we developed a pseudovirus-based neutralization assay for SARS-CoV-2, which would be readily adapted to SARS-CoV-2 variants for evaluating antibodies.

  • 标签: COVID-19 SARS-CoV-2 variants Pseudovirus Neutralizing antibody RBD
  • 简介:AbstractThe immune responses and the function of immune cells among asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection cases, especially in immuno-compromised individuals, remain largely unknown. Here we present a case of asymptomatic SARS-CoV-2 infection that lasted for at least 67 days. The patient has administrated Thymalfasin as 1.6 mg per dose every other day from Day 45 to 70, plus 200 mg per dose Arbidol antiviral therapy three doses per day from Day 48 to 57. Throughout the infection, no anti-SARS-CoV-2 specific IgM or IgG antibodies were detected. Instead, the patient showed either a low percentage or an absolute number of non-classical monocytes, dendritic cells (DCs), CD4+ T cells, and regulatory T cells (Tregs), which may account for the clinical feature and absence of antibody response. This case may shed new light on the outbreak management related to control/prevention, treatment, and vaccination of SARS-CoV-2 and other virus infections in immunocompromised individuals.

  • 标签: SARS-CoV-2 COVID-19 Asymptomatic infection Antibody response Immune cells
  • 简介:AbstractSince severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified during late 2019, the sustained spread of this pathogen within the human population has caused worldwide disruption with staggering infection rates and death tolls. Due to the accumulation of mutations in SARS-CoV-2, the virus has evolved into many variants, five of which have been listed as variants of concern VOCs by the World Health Organization (WHO). Multiple animal models of SARS-CoV-2 have been developed to evaluate vaccines and drugs and to assess the pathogenicity, transmissibility and antiviral measures of these VOCs. Here, we review the cutting-edge research based on mouse, hamster, ferret and non-human primate models for evaluating SARS-CoV-2 with a focus on the Omicron variant, and highlight the importance of updating vaccines in a timely manner in order to mitigate the negative effects of SARS-CoV-2 infections in the human population.

  • 标签: SARS-CoV-2 Animal models Variants of concern Omicron
  • 简介:AbstractA series of stringent non-pharmacological and pharmacological interventions were implemented to contain the pandemic but the pandemic continues. Moreover, vaccination breakthrough infection and reinfection in convalescent coronavirus disease 2019 (COVID-19) cases have been reported. Further, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants emerged with mutations in spike (S) gene, the target of most current vaccines. Importantly, the mutations exhibit a trend of immune escape from the vaccination. Herein the scientific question that if the vaccination drives genetic or antigenic drifts of SARS-CoV-2 remains elusive. We performed correlation analyses to uncover the impacts of wide vaccination on epidemiological characteristics of COVID-19. In addition, we investigated the evolutionary dynamics and genetic diversity of SARS-CoV-2 under immune pressure by utilizing the Bayesian phylodynamic inferences and the lineage entropy calculation respectively. We found that vaccination coverage was negatively related to the infections, severe cases, and deaths of COVID-19 respectively. With the increasing vaccination coverage, the lineage diversity of SARS-CoV-2 dampened, but the rapid mutation rates of the S gene were identified, and the vaccination could be one of the explanations for driving mutations in S gene. Moreover, new epidemics resurged in several countries with high vaccination coverage, questioning their current pandemic control strategies. Hence, integrated vaccination and non-pharmacological interventions are critical to control the pandemic. Furthermore, novel vaccine preparation should enhance its capabilities to curb both disease severity and infection possibility.

  • 标签: SARS-CoV-2 Vaccine Genetic evolution Genetic drift Antigenic drift Lineage divergence Epidemiological characteristics
  • 简介:摘要SARS-CoV-2是引起COVID-19大流行的病原体,对人类的生命健康和社会稳定造成严重危害。在重型COVID-19病例中,病毒感染引发细胞因子风暴,导致多器官炎症反应过度直至衰竭,最终导致患者死亡。最近研究显示,核苷酸结合寡聚化结构域样受体蛋白3 (nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3, NLRP3)炎症小体的激活是SARS-CoV-2致病的重要机制,SARS-CoV-2可通过多种途径激活NLRP3炎症小体,从而诱发大量促炎细胞因子释放。本文综述了SARS-CoV-2感染激活NLRP3炎性小体及其分子机制,并总结靶向抑制NLRP3炎症小体的研究进展,为治疗SARS-CoV-2感染提供新策略。

  • 标签: 核苷酸结合寡聚化结构域样受体蛋白3炎症小体 SARS-CoV-2 细胞因子风暴 靶向抑制
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  • 简介:AbstractLike antibody evaluation, using an effective antigen-specific T-cell immunity assessment method in coronavirus disease 2019 (COVID-19) patients, survivors and vaccinees is crucial for understanding the immune persistence, prognosis assessment, and vaccine development for COVID-19. This study evaluated an empirically adjusted enzyme-linked immunospot assay for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T-cell immunity in 175 peripheral blood samples from COVID-19 convalescents and healthy individuals. Results of viral nucleic acid were used as the gold standard of infection confirmation. The SARS-CoV-2M peptide pool had higher sensitivity of 85% and specificity of 71% for the single peptide pool. For combined peptide pools, the parallel evaluation (at least one of the peptide pools is positive) of total peptide pools (S1&S2&M&N) had higher sensitivity (up to 93%), and the serial evaluation (all peptide pools are positive) of total peptide pools had higher specificity (up to 100%). The result of the serial evaluation was better than that of the parallel evaluation as a whole. The detection efficiency of M and N peptide pool serial evaluation appeared the highest, with a sensitivity of 80% and specificity of 93%. This T-cell immunity detection assay introduced in this report can achieve high operability and applicability. Therefore, it can be an effective SARS-CoV-2-specific cellular immune function evaluation method.

  • 标签: SARS-CoV-2 COVID-19 T-cell response ELISpot assay Sensitivity Specificity
  • 简介:AbstractThe pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to unprecedented social and economic disruption. Many nucleic acid testing (NAT) laboratories in China have been established to control the epidemic better. This proficiency testing (PT) aims to evaluate the participants’ performance in qualitative and quantitative SARS-CoV-2 NAT and to explore the factors that contribute to differences in detection capabilities. Two different concentrations of RNA samples (A, B) were used for quantitative PT. Pseudovirus samples D, E (different concentrations) and negative sample (F) were used for qualitative PT. 50 data sets were reported for qualitative PT, of which 74.00% were entirely correct for all samples. Forty-two laboratories participated in the quantitative PT. 37 submitted all gene results, of which only 56.76% were satisfactory. For qualitative detection, it is suggested that laboratories should strengthen personnel training, select qualified detection kits, and reduce cross-contamination to improve detection accuracy. For quantitative detection, the results of the reverse transcription digital PCR (RT-dPCR) method were more comparable and reliable than those of reverse transcription quantitative PCR (RT-qPCR). The copy number concentration of ORF1ab and N in samples A and B scattered in 85, 223, 50, and 106 folds, respectively. The differences in the quantitative result of RT-qPCR was mainly caused by the non-standard use of reference materials and the lack of personnel operating skills. Comparing the satisfaction of participants participating in both quantitative and qualitative proficiency testing, 95.65% of the laboratories with satisfactory quantitative results also judged the qualitative results correctly, while 85.71% of the laboratories with unsatisfactory quantitative results were also unsatisfied with their qualitative judgments. Therefore, the quantitative ability is the basis of qualitative judgment. Overall, participants from hospitals reported more satisfactory results than those from enterprises and universities. Therefore, surveillance, daily qualitiy control and standardized operating procedures should be strengthened to improve the capability of SARS-CoV-2 NAT.

  • 标签: Proficiency testing SARS-CoV-2 Nucleic acid testing Reference material Quality assessment Pseudovirus