BACKGROUND:Noroviruses (NoV) are key pathogens causing acute gastroenteritis (AGE) in children, with a significant disease burden, especially in developing nations. This study aims to track changes in NoV genotype epidemiology before and after the lifting of COVID-19 non-pharmacological interventions (NPIs) in Harbin. METHODS:In this study, we investigated fecal samples collected by the Harbin Children's Hospital from attended AGE preschoolers between January 2022 and December 2023. The detection of norovirus was performed using RT-qPCR. Later, the norovirus-positive samples were typed by conventional RT-PCR and Sanger sequencing. Phylogenetic analysis, recombination breakpoint analysis, and mutation analysis were also performed. RESULTS:230 NoV-positive samples were detected in the two years, with a positive rate of 39.1 %, belonging to NoV GⅡ. According to the partial sequences of the RNA-dependent RNA polymerase (RdRp) and VP1 gene sequence analysis, seven different genotypes were detected, being GII.4[P16] (61.5 %) the predominant one. Furthermore, the mutation analysis indicated that Harbin-Nov-066-2023 exhibited a mutation from valine to isoleucine at positions 290aa and 386aa in the VP1 region, respectively, compared to Harbin-Nov-022-2022. Additionally, strains from the rare type GⅡ.8[P8] were detected in 2022. CONCLUSIONS:These findings may contribute novel data to the genetic database of norovirus in Harbin. This could facilitate investigations into the genetic evolution of this virus, developing vaccines to target dominant genotypes and the molecular basis of norovirus genetics.

The emergence of novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant, Omicron, has intensified the spread of the global coronavirus disease 2019 (COVID-19) pandemic.The new variant, Omicron, was first identified in Africa, which was classified as B. 1.1.529 on the Pango lineage evolutionary classification system.World Health Organization(WHO) designated the variant as a Variant of Concern(VOC) and named it as Omicron variant.Omicron contains a lot of mutations and spreads faster compared with other previous identified VOC variants.Omicron has great changes in infectivity and immunity, and it’s possible to have the risk of immune escape and breaking through the immune protection effect of current vaccines.Within about a month since it was discoved, omicron has spread rapidly across 77 countries and regions, which has attracted extensive attention worldwide.This review briefly describes the discovery process, epidemiology, genomic mutation characteristics, immune escape, prevention and control strategies of Omicron variant.

病毒蛋白质结构属于医学微生物学的教学难点问题.为突破难点,我们以呼吸道病毒的蛋白质结构和变异为核心,将生物信息学中的序列检索、比对、蛋白质结构同源建模,与进化轨迹可视化等知识紧密结合.线上以流感病毒为例讲解每个环节的操作流程,学生根据指导书对腺病毒和新冠肺炎病毒进行分析.线下讨论课形式由学生汇报分析结果,该教学设计在实践中取得了良好的效果和反馈,是新冠疫情背景下线上线下进行教学的有益探索.

Aim: To reconstruct the ancestral sequence of human adenoviral hexon protein by combining sequence variations and structural information. And to provide a candidate hexon protein for developing new adenoviral vector capable of escaping the pre-existing immunity in healthy populations. Methods: The sequences of 74 adenovirus-type strains were used to predict the ancestral sequence of human adenovirus hexon protein using FastML and MEGA software. The three-dimensional structure model was built using homology modeling methods. The immunological features of ancestral loop 1 and loop 2 regions of sequences were tested using protein segments expressed in a prokaryotic expression system and polypeptides synthesized with human serum samples. Results: The tower region of the hexon protein had the highest sequence variability, while the neck and base regions remained constant among different types. The modern strains successfully predicted the common ancestral sequence of the human adenovirus hexon. The positive sera against neutralizing epitopes on the common ancestor of adenoviral hexon were relatively rare among healthy adults. Conclusion: The existing strains inferred the common ancestor of human adenoviruses, with epitopes never observed in the current human strains. The predicted common ancestor hexon is a good prospect in the improvement of adenovirus vectors.

目的 研究抗腺病毒药物α-蒎烯对病毒抑制的作用及相关机制.方法 采用细胞病变抑制实验和噻唑蓝(MTT)比色法观察单体α-蒎烯对人腺病毒3型的抑制作用.同时利用原子力显微镜观察病毒与药物直接作用后病毒形态学的改变;用激光共聚焦显微镜检测药物在吸附阶段对病毒的作用效果.结果 MTT结果显示α-蒎烯对病毒的抑制作用主要表现在对病毒的直接灭活作用和对细胞的保护作用,从而阻挡病毒进入细胞.结论 α-蒎烯具有抗腺病毒作用,为研发天然、高效、低毒的抗腺病毒的药物提供了科学依据.

Abstract Objective A continuous survey on influenza was conducted in Hulunbuir, China from January 2010 to May 2019 to reveal epidemiological, microbiological and air pollutants associated with laboratory-confirmed influenza cases. Methods Influenza-like illness and severe acute respiratory infection subjects were enrolled from a sentinel hospital in Hulunbuir during the study period for epidemiological and virological investigation. The association between air pollutants and influenza-positivity rate was assessed by a generalised additive model. Results Of 4667 specimens, 550 (11.8%) were tested positive for influenza. The influenza-positivity was highest in the age groups of 5–14 years, 50–69 years and ⩾70 years. We found that the effect of particulate matter ⩽2.5 μm (PM2.5) concentrations on the influenza-positivity rate was statistically significant, particularly on day lag-4 and lag-5. Genetic characterisations showed that (H1N1) pdm09 strains belonged to subclade 6B.1 and that influenza B isolates belonged to subclade 1A-3Del, with significant substitutions in the haemagglutinin and neuraminidase proteins compared with those in the WHO-recommended vaccine strains. Conclusions Elderly individuals and school-age children were at high risk for influenza infection. PM2.5 concentrations showed significant effects on influenza-positivity rate in Hulunbuir, which could be considered in local influenza prevention strategies.

In the last decade CRISPR/Cas systems have been used extensively in different areas of research from bacterial genotyping to genetic engineering. CRISPR/Cas systems are accurate and precise molecular devices designed by the nature, with the primary role being bacterial defence against foreign genetic elements, mainly bacteriophages. The recent advances in sequencing technologies have created opportunities for application of CRISPR/Cas systems in personalized phage therapy and in fundamental studies of co-functioning of bacterial and phage populations in the nature. However, as always, new opportunities mean new technical challenges and demands for innovative bioinformatics tools. This review introduces an initiative of the BRICS consortium, consisting of three research centres in Russia, China and South Africa, to develop a comprehensive interactive resource to source data and software tools for personalised phage therapy.

腺病毒种类繁多且分布广泛,是引起人类呼吸道感染的重要病原之一.腺病毒感染所致的疾病目前没有特效药,而中药具有耐药性低和多靶点作用机制等优势,所以在治疗腺病毒感染方面具有广阔的发展前景.文章从紫草素、黄芪甲苷、肉桂醛、松针油、大青叶提取物和穿心莲内酯磺化物等中药单体及有效成分的抗腺病毒研究,双黄连制剂、热毒宁注射液、喜炎平注射液等中药复方制剂的抗腺病毒研究和部分药物的临床应用等3个方面进行综述,为寻找抗病毒药物提供依据.

人腺病毒是一种能引起人类多种疾病的DNA病毒,迄今为止发现了包括A～G等7个种、80多个型别.本文对腺病毒的结构、分类标准进行了介绍,同时对新型别人腺病毒及其分型鉴定方法、产生机制进行综述.对人腺病毒多方面的了解有助于更好的探究其进化机制、组织嗜性及致病性,加强对腺病毒感染的预防和治疗.

目的 了解哈尔滨地区住院患者呼吸道病毒感染状况及流行趋势,为疾病防治和腺病毒流行监测提供参考.方法 采用直接免疫荧光法,检测2017年3月 ～2018年2月哈尔滨地区住院患者痰液标本呼吸道病毒的感染情况.选择1例腺病毒阳性标本利用空斑实验进行分离纯化,利用PCR扩增六邻体L1区、纤突和E1A区并进行PCR产物序列测定和Blast比对分析鉴定型别.结果 七种常见呼吸道病毒检测总体阳性率为14.36％.呼吸道合胞病毒阳性率最高为4.18％,腺病毒阳性率为1.82％.不同季节病毒检测阳性率差异有统计学意义(P<0.05).从腺病毒检测阳性标本中分离到一株人腺病毒毒株,进行PCR产物测序和分析,初步鉴定该毒株为人腺病毒3型.结论 哈尔滨地区呼吸道病毒感染的病原体主要以呼吸道合胞病毒为主.呼吸道病毒感染流行季节为冬春季节,应加强哈尔滨地区呼吸道病毒流行情况监测.

Objective To clone and express the hyper-variable region in the hexon protein of human adenovirus,understand its structure and function,and lay a foundation for a genetic engineering vaccine candi-date of human adenovirus. Methods We selected the target gene which was the hypervariable region of hexon, according to the model of human adenovirus hexon predicted by bioinformatics software. The corresponding prim-ers were designed. The hexon,preserved by our team,was as a template to amplify the desired gene by PCR. The recombinant plasmid was constructed by directly cloning into the vector pQE32. The positive engineering vector, confirmed by the cleavage of endonuclease and nucleic acid sequence,was transformed into E. coli. M15 to ex-press the His-tagged protein. Then the target protein was purified by Ni-Resin column affinity chromatography. Results The recombinant plasmid containing the hyper-variable region fragment in the hexon protein of human adenovirus was constructed. The conditions for the target gene expressing protein efficiently in E. coli M15 were found. We purified the target protein with a molecular weight of 188000,which was consistent with the predic-tion by bioinformatics. Conclusion The fragment of hexon protein hyper-variable region is cloned,expressed and purified successfully.

Background: Respiratory infections pose a great challenge in global health, and the prevalence of viral infection in adult patients has been poorly understood in northeast China. Harbin is one of the major cities in northeast China, and more than half of any given year in Harbin is occupied by winter. To reveal the viral etiology and seasonality in adult patients from Harbin, a 4-year consecutive survey was conducted in Harbin, China. Methods: From January 2014 to December 2017, specimens were obtained from adult patients admitted to the Second Affiliated Hospital of Harbin Medical University with lower respiratory tract infections. Sputum samples were examined by direct immunofluorescence assays to detect seven common respiratory viruses, including influenza virus (type A and B), parainfluenza virus (type 1 to 3), respiratory syncytial virus and adenovirus. Adenovirus positive samples were seeded onto A549 cells to isolate viral strains. Phylogenetic analysis was conducted on the highly variable region of adenoviral hexon gene. Results: A total of 1,300 hospitalized adult patients with lower respiratory tract infections were enrolled, in which 189 patients (14.5%) were detected as having at least one viral infection. The co-infection rate in this study was 25.9% (49/189). The dominant viral pathogen from 2014 to 2017 was parainfluenza virus, with a detection rate of 7.2%, followed by influenza virus, respiratory syncytial virus and adenovirus. Based on the climate seasons determined by daily average temperature, the highest overall viral detection rate was detected in spring (22.0%, 52/236), followed by winter (13.4%, 109/813), autumn (11.4%, 13/114) and summer (10.9%, 15/137). Adenovirus type 3 strains with slight variations were isolated from positive cases, which were closely related to the GB strain from the United States, as well as the Harbin04B strain isolated locally. Conclusion: This study demonstrated that common respiratory viruses were partially responsible for hospitalized lower respiratory tract infections in adult patients from Harbin, China, with parainfluenza virus as the dominant viral pathogen. Climate seasons could be rational indicators for the seasonality analysis of airborne viral infections. Future surveillance on viral mutations would be necessary to reveal the evolutionary history of respiratory viruses.

Objective To clone and express basal region fragment of hexon protein from HAdV-3 as to lay a foundation for thorough understanding the antigenicity and protein structure of hexon,which may lead to development of a vaccine candidate or an Adv diagnostic reagent.Methods The hexon protein basal region fragment was amplified by PCR using genomic DNA of HAdV-3 (human adenovirus 3) as template.Then the target DNA was directionally cloned to pQE32 plasmid.The recombinant plasmid was transformed into competent E.coli.M15 to express the target protein.Then the target protein was purified by Ni-Resin column affinity chromatography.Results The recombinant plasmid was successfully constructed.The recombinant protein was highly expressed in E.coli.M15.Conclusion The fragment of HAdV-3 hexon protein basal region is successfully cloned and expressed.

AIM:Numerous epidemiologic studies have evaluated the association between overweight and hand osteoarthritis; However, the existing results are inconsistent.METHODS:Systematic searches were performed and reference lists from the retrieved trials were searched. This meta-analysis and meta-regression was executed to identify all English-language articles that quantitatively assess the strength of associations between body mass index and hand osteoarthritis risk. Study-specific incremental estimates were standardized to determine the risk associated with a 5 kg/m2 increase in body mass index. We conducted the study according to the guidelines for the meta-analysis of observational studies in epidemiology.RESULTS:Of the 21 studies included, 13 were cross-sectional studies, three were case control studies and five were cohort studies. The pooled summary estimates were 1.10 (95%CI: 0.98-1.24) with no significant difference (P = 0.09). Subgroup analysis shows that body mass index was positively associated with hand osteoarthritis in cross-sectional studies (1.05 [95%CI: 1.02-1.08] P < 0.01), while with no significant difference was found in case-control studies (1.28 [95%CI: 0.87-1.88]) and in cohort studies (1.06 [95%CI: 0.71-1.58]) (P = 0.21 and P = 0.77, respectively). A weak but significant effect on radiographic hand osteoarthritis risk was found. The summary estimates were 1.06 (95%CI: 1.02-1.10) in studies defined by radiography and 1.25 (95%CI: 1.06-1.49) by radiography and clinically (P < 0 .01 and P = 0.01, respectively).CONCLUSION:It appears that increased body mass index contributes to a positively moderate effect on susceptibility to hand osteoarthritis, as defined radiographically and/or radiographically and clinically. The effects vary by study design and osteoarthritis definition.

在卫生微生物学教学过程中应用PBL教学法,探讨一种适合中国卫生微生物学理论教学的新方法.在理论学习时,教师采用PBL教学模式,能够显著提高学生的学习成绩,对学生的学习兴趣、学习能力、实践能力等方面有一定的帮助,是PBL在卫生微生物学教学领域发展中一次有益的尝试.

目的 预测人腺病毒55型六邻体蛋白B细胞抗原表位.方法 使用DNAStar软件Protean模块,PSIPRED在线服务器和SWISS-MODEL在线服务器联合预测人腺病毒55型六邻体蛋白B细胞抗原表位.结果 构建了人腺病毒55型六邻体蛋白三级结构模型和预测得到5个候选的人腺病毒55型六邻体抗原表位.结论 成功预测人腺病毒55型六邻体蛋白B细胞抗原表位,为进一步研制疫苗和检测试剂奠定了基础.

In the present study, we aimed to investigate platelet activation induced by adenovirus type 3 (HAdV3) in vitro. Platelet-rich plasma (PRP) or whole blood was incubated with or without HAdV at various concentrations. Platelet aggregation, platelet counting, fibrinogen and expression of platelet membrane antigens (CD41a and CD62P) were determined following incubation with HAdV for different periods of time. The results demonstrated that HAdV at the concentrations of 109-1011 vp/ml enhanced adenosine diphosphate (ADP) or ristocetin-induced platelet aggregation, however did not alter the platelet count. Infection with HAdVs also reduced fibrinogen level. P-selectin and CD41a appeared rapidly on the surface after platelets were incubated with HAdVs in vitro for 30 min. In conclusion, HAdVs may induce activation of platelets and lead to a pre-thrombotic state of peripheral blood. This finding may aid in the development of measures to prevent severe HAdV infection.

Objective To detect, isolate and identify the type of adenovirus ( AdV) in sputum or throat swab specimens collected from respiratory infection patients who hospitalized in the Second Affiliated Hospital of Harbin Medical University.Methods The AdVs were prelimina-rily screened from the specimens by using direct immunofluorescence technique.The AdV posi-tive specimens were inoculated onto A549 cells and then further isolated and purified by using plaque assay methods.The nucleic acid sequences of adenoviral penton and hexon genes were amplified by PCR.The amplified PCR products were subject to sequence using Sanger’ s meth-od.The sequences were compared with the sequences of known penton and hexon genes in GenBank database by BLAST software to identify the exact type of adenovirus.Results One type of adenovirus was successfully separated from our specimens.The penton and hexon se-quences were 100%homological to those of human adenovirus type 7.Thus the isolated AdV strain was identifed as AdV type 7.Conclusion A strain of human respiratory adenovirus type 7 is successfully isolated from sputum specimens of patients in Harbin area.

Aim To investigate the anti-adenovirus effect of astragaloside IV in vitro.Methods Anti-adenovirus effect of astragaloside IV was measured by cytopathogenic effect(CPE) and MTT method.The expression of hexon protein in biosynthesis stage was measured by laser scanning confocal microscope.Results The results of CPE and MTT showed that astragaloside IV may inhibit the proliferation of adenovirus through direct inactivation of the adenovirus,blockage of virus replication and inhibition of virus absorption,the inhibition rate of virus had a positive correlation with the drug concentration,and astragaloside IV did not block the virus uptake into host cells in the mode of protective effect.The expression of hexon protein was significantly reduced in biosynthesis stage in astragaloside IV group than that in virus group.Conclusion Astragaloside IV has anti-adenovirus effect in vitro,which may be related to the inhibition of hexon protein expression in biosynthesis stage.

This research reveals the phylogenetic history and structural information of the hemagglutinin(HA) and neuraminidase(NA) from novel avian influenza virus A/Hangzhou/1/2013(H7N9_2013) strain from human infected in China. Strains closely related to the H7N9_2013 strain were obtained from Nation Center for Biotechnology Information(USA)-basic local alignment search tool(NCBI-BLAST) searching, and the phylogenetic trees were constructed. The 3D structures of HA and NA from H7N9_2013 strain were built by homology modeling technology, and molecular dynamics(MD) simulations were performed on the high-performance computer cluster. Characteristic amino acid sites were then screened from multiple sequence alignment(MSA) via home-made Python script and mapped onto the 3D structures. The thermodynamic characteristic root-mean-square-fluctuation (RMSF) of these sites in the structure was also analyzed with MD trajectories. The HA of H7N9_2013 strain is closely related to the A/duck/Zhejiang/12/2011 strain isolated in China, while the NA of H7N9_2013 strain is mostly related to the A/mallard/Czech Republic/13438-29K/2010 strain isolated in Europe. The 3D structures of HA and NA from H7N9_2013 stain are mostly identical to the existing structure of H7 and N9. A total of 11 and 14 characteristic amino acid sites were identified in HA and NA, respectively, in H7N9_2013. Structural analysis indicates that certain sites in the top region of HA are important, at which the mutation of some amino acids can impact the receptor binding that may be related to its infection of human beings.