Long-term exposure to air pollution and cerebrovascular disease:findings from Beijing Health Management Cohort study

The relationship between air pollution and cerebrovascular disease has become a popular topic,yet research findings are highly heterogeneous.This study aims to investigate this association based on detailed individual health data and a precise evaluation of their exposure levels.The integrated models of generalized additive model,land use regression model and back propagation neural network were used to evaluate the exposure concentrations.And doubly robust additive model was conducted to explore the association between cerebrovascular disease and air pollution after adjusted for demographic characteristics,physical examination,disease information,geographic and socioeconomic status.A total of 25097 subjects were included in the Beijing Health Management Cohort from 2013 to 2018.With a 1µg/m^(3)increase in the concentrations of PM_(2.5),SO_(2)and NO_(2),the incidence risk of cerebrovascular disease increased by 1.02(95%CI:1.008–1.034),1.06(95%CI:1.034–1.095)and 1.02(95%CI:1.010–1.029)respectively.Whereas CO exposure could decrease the risk,with an odds ratio of 0.38(95%CI:0.212–0.626).In the subgroup analysis,individuals under the age of 50 with normal BMI were at higher risk caused by PM2.5,and So2 was considered more hazardous to women.Meanwhile,the protective effect of CO on women and those with normal BMI was stronger.Successful reduction of long-term exposure to PM2.5,SO_(2)and NO_(2)would lead to substantial benefits for decrease the risk of cerebrovascular disease especially for the health of the susceptible individuals.

Development of rapid nucleic acid assays based on the recombinant polymerase amplification for monkeypox virus

Dear Editor,Monkeypox virus(MPXV),an enveloped double-stranded DNA virus with 190 open-reading frames and a genome length of about 200 kb,belongs to the genus Orthomyxovirus(OPXV;subfamily Chordopoxvirinae,family Poxviridae),which causes a disease with symptoms similar to,but less severe than,smallpox.MPXV is subdivided into two clades:clade I for the former Congo Basin clade and clade II for the former West African,and the clade I is more pathogenic.The clade II consists two subclades,clade IIa and clade IIb,with the latter referring primarily to the group of variants largely circulating in the 2022 global outbreak(ICTV,2022;Bunge et al.,2022;Mauldin et al.,2022).

蜱传脑炎病毒跨过血脑屏障的体外实验

【目的】构建蜱传脑炎病毒(Tick-borne encephalitis virus,TBEV)跨血脑屏障研究的体外细胞模型,研究2种不同细胞的TBEV培养物在病毒跨过血脑屏障中的主要差异,从而为进一步TBEV跨血脑屏障的分子机制研究奠定基础。【方法】利用人脑微血管内皮细胞(Human brain microvascular endothelial cells,hCMEC/D3)构建体外血脑屏障的细胞模型。用BHK-21细胞中培养的蜱传脑炎病毒感染人脑微血管内皮细胞,检测TBEV在hCMEC/D3中的复制增殖情况;将TBEV加入体外血脑屏障模型的上层微孔中,用实时荧光定量PCR和噬斑测定的方法检测跨过血脑屏障的病毒量;将感染TBEV的人单核细胞加入血脑屏障模型的上层微孔中,观察渗漏进下层孔中的淋巴细胞,并用实时荧光定量PCR和噬斑测定的方法检测跨过血脑屏障的病毒量。利用伊文思蓝标记的白蛋白确定血脑屏障细胞的渗透率变化。【结果】实时荧光定量PCR和病毒滴度测定结果表明,TBEV不能在hCMEC/D3细胞中复制增殖,也不能直接跨过血脑屏障;然而,人单核细胞THP-1感染TBEV后,尽管单核细胞不能直接携带TBEV跨过血脑屏障,但THP-1中产生的病毒却能跨过血脑屏障模型进入下层孔中,并引起血脑屏障渗透率的增高。【结论】单核细胞有助于TBEV跨过血脑屏障。

Reverse Transcription Recombinase Polymerase Amplification Assays for Rapid Detection of Tick-Borne Encephalitis Virus Infection

Dear Editor,Tick-borne encephalitis virus(TBEV)belongs to the genus Flavivirus within the family Flaviviridae and includes three subtypes:Siberian,European,and Far Eastern.TBEV infects humans via tick bites;indeed,at least 10,000 human cases of encephalitis caused by TBEV are reported annually in Russia,China,and European countries(Banzhoff et al.2008;Carletti et al.2017).

An integrated rapid nucleic acid detection assay based on recombinant polymerase amplification for SARS-CoV-2

Dear Editor,Severe acute respiratory syndrome coronavirus-2(SARS-Co V-2)is a novel coronavirus that causes the outbreak of coronavirus disease 2019(COVID-19)(Li et al.,2020a).Viral nucleic acid testing is the standard method for the laboratory diagnosis of COVID-19(Wu et al.,2020a;Zhu et al.,2020).Currently,a variety of qPCR-based detection kits are used for laboratory-based detection and confirmation of SARS-CoV-2 infection(Corman et al.,2020;Hussein et al.,2020;Ruhan et al.,2020;Veyer et al.,2020).Conventional qPCR involves virus inactivation,nucleic acid extraction,and qPCR amplification procedures.Therefore,the process is complicated,which usually takes longer than 2 h,and requires biosafety laboratories and professional staff.Thus,qPCR is not suitable for use in field or medical units.

Development of a rapid neutralizing antibody test for SARS-CoV-2 and its application for neutralizing antibody screening and vaccinated serum testing

Background:Since the outbreak of coronavirus disease(COVID-19),the high infection rate and mutation fre-quency of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the causative agent,have contributed to the ongoing global pandemic.Vaccination has become the most effective means of controlling COVID-19.Tra-ditional neutralizing tests of sera are complex and labor-intensive,therefore,a rapid test for detecting neutralizing antibodies and antibody status post-immunization is needed.Methods:Based on the fact that antibodies exhibit neutralizing activity by blocking the binding of the S protein receptor-binding domain(S-RBD)to ACE2,we developed a rapid neutralizing antibody test,ACE2-Block-ELISA.To evaluate the sensitivity and specificity,we used 54 positive and 84 negative serum samples.We also tested the neutralizing activities of monoclonal antibodies(mAbs)and 214 sera samples from healthy individuals im-munized with the inactivated SARS-CoV-2 vaccine.Results:The sensitivity and specificity of the ACE2-Block ELISA were 96.3%and 100%,respectively.For neu-tralizing mAb screening,ch-2C5 was selected for its ability to block the ACE2-S-RBD interaction.A plaque assay confirmed that ch-2C5 neutralized SARS-CoV-2,with NT 50 values of 4.19,10.63,and 1.074μg/mL against the SARS-CoV-2 original strain,and the Beta and Delta variants,respectively.For the immunized sera samples,the neutralizing positive rate dropped from 82.14%to 32.16%within 4 months post-vaccination.Conclusions:This study developed and validated an ACE2-Block-ELISA to test the neutralizing activities of an-tibodies.As a rapid,inexpensive and easy-to-perform method,this ACE2-Block-ELISA has potential applications in rapid neutralizing mAb screening and SARS-CoV-2 vaccine evaluation.