High-coverage SARS-CoV-2 genome sequences acquired by target capture sequencing

In this study, we designed a set of SARS-CoV-2 enrichment probes to increase the capacity for sequence-based virus detection and obtain the comprehensive genome sequence at the same time. This universal SARS-CoV-2 enrichment probe set contains 502 120 nt single-stranded DNA biotin-labeled probes designed based on all available SARS-CoV-2 viral sequences and it can be used to enrich for SARS-CoV-2 sequences without prior knowledge of type or subtype. Following the CDC health and safety guidelines, marked enrichment was demonstrated in a virus strain sample from cell culture, three nasopharyngeal swab samples (cycle threshold [C_t] values: 32.36, 36.72, and 38.44) from patients diagnosed with COVID-19 (positive control) and four throat swab samples from patients without COVID-19 (negative controls), respectively. Moreover, based on these high-quality sequences, we discuss the heterozygosity and viral expression during coronavirus replication and its phylogenetic relationship with other selected high-quality samples from the Genome Variation Map. Therefore, this universal SARS-CoV-2 enrichment probe system can capture and enrich SARS-CoV-2 viral sequences selectively and effectively in different samples, especially clinical swab samples with a relatively low concentration of viral particles.     

Risk factors for severe hand,foot, and mouth disease infected with Coxsackievirus A6: A hospital-based case-control study

Coxsackievirus 6 (CV-A6) has been emerging as another predominant serotype for severe hand, foot, and mouth disease (HFMD) in China, after the introduction of enterovirus 71 inactivated vaccine (EV71 vaccine) for 3 years. Data on the risk factors for severe HFMD infected with CV-A6 are limited. We interviewed the caregivers to collected data on HFMD patients who sought medical care in the People's Hospital of Baoan district, Shenzhen, from 2015 to 2017. Totally, 131 severe patients were frequency-matched by age and gender with 174 mild patients infected with CV-A6. Univariable and multivariable logistic regression analyses were conducted to analyze the risk factors for severe CV-A6 HFMD. The average age was 20.62 ± 14.18 months and 20.52 ± 12.76 months for severe and mild patients, respectively. Multivariate analyses indicated complications at birth (odds ratio [OR], 4.18; 95% confidence interval [CI]: 1.64-10.63), peak body temperature over 39°C (OR, 4.04; 95% CI: 2.29-7.10) and first-born child (OR, 2.17; 95% CI: 1.27-3.70) increased the risk of severe HFMD infected with CV-A6. Breastfeeding (OR, 0.52; 95% CI: 0.32-0.87), and washing hands after playing frequently (OR, 0.58; 95% CI: 0.34-0.97) were negatively associated with severe illness. Compared with HFMD with infection of EV-A71, complications at birth and first-born child were newly found to be associated with severe illness in HFMD patients infected with CV-A6.     

2017年深圳市宝安区一起人星状病毒引起的急性胃肠炎暴发疫情调查

目的探讨2017年深圳市宝安区一起学校急性胃肠炎暴发疫情的病原体和传播危险因素。方法2017年10 — 11月,按照定义搜索深圳市宝安区某学校一起急性胃肠炎暴发疫情病例,采用描述性流行病学方法进行分析,并选择罹患率较高的5个班级作为调查对象,采用回顾性队列研究方法,调查269名学生的病例接触史、就餐、饮水习惯等暴露情况,用logistic回归分析其流行因素。 采集患者的粪便或肛拭子,以及直饮机水、桶装水、厕所洗手水等水样,运用试剂盒检测病毒核酸。结果2017年10月20日至11月17日,共搜集病例98例,总罹患率为3.21%（98/3 052）,男、女性罹患率分别为3.59%（61/1 698）和2.73%（37/1 354）,差异无统计学意义（χ2＝1.782,P＝0.181）。 第三教学楼学生罹患率最高,为3.94%（6/152）,其次是主教学楼学生,罹患率为3.62%（84/2 319）。 各教学楼学生罹患率差异有统计学意义（χ2＝7.837,P＝0.049）,主教学楼不同楼层学生罹患率的差异无统计学意义（χ2＝1.861,P＝0.713）。 回顾性队列研究共调查269人,饮直饮水（RR＝6.975,95% CI:1.871～26.027）和接触病例（RR＝6.514,95% CI:2.314～18.358）是危险因素。 粪便和肛拭子样本星状病毒核酸检测总阳性率为28.00%（7/25）,水样本均阴性。结论结合现场流行病学调查和实验室检测结果,判断为一起主要通过接触传播引起的人星状病毒感染暴发疫情,建议学校早发现、早隔离、早报告,尽可能减少健康学生接触病例。     

ICP-MS法测定微波条件下陶瓷餐具中的元素浸出

目的:测定微波条件下陶瓷餐具的浸出元素,以期了解陶瓷餐具微波加热食品的安全性。方法:采用ICP-MS(电感耦合等离子体质谱)法测定不同微波条件下陶瓷餐具的元素浸出液。结果:浸出液中硒、银、锡、汞、等元素的含量小于检出限,砷、锰、铁、铜、镉、镍等元素的含量较低,铝、锌、铅等元素则有相对明显的浸出;元素的浸出量与微波的时间及微波后的浸泡时间成正比,与微波浸泡次数成反比。结论:在酸性微波条件下,陶瓷餐具中的部分元素会有一定量浸出,浸出量与微波的时间及微波后的浸泡时间成正比,浸出量随着浸泡次数的增加而减少,不具有持续效应。     

Spatial spread and demographic expansion of Lyme borreliosis spirochaetes in Eurasia

The Lyme borreliosis (LB) group of spirochaetes currently comprises 18 named species that vary in their geographic distribution, host specificity and ability to cause disease in humans. In Europe three species are most abundant, Borrelia afzelii, Borrelia garinii and Borrelia valaisiana but only two of these (B. garinii and B. afzelii) are regularly found in Asia as well. A recently published study has shown that Borrelia species associated with birds, such as B. garinii, showed limited geographic structuring between European countries while, the rodent associated species, B. afzelii, showed extensive spatial structuring in Europe. Here, we use multilocus sequence analysis to show that when the wider, inter-continental, distribution is considered, there is evidence of spatial structuring even in the bird-associated species B. garinii. Furthermore, our investigations into historical LB populations provided evidence for range expansions of B. garinii and B. afzelii populations in Europe in the distant past. We propose that the expansion of B. afzelii in Europe may be linked to rodent population expansions after the last glacial maximum.     

深圳市宝安区医疗机构消毒质量调查

目的了解深圳市宝安区医疗机构消毒质量状况,为改善医疗机构消毒管理工作提供参考。方法采用现场采样和细菌检测方法,对深圳市宝安区各级医疗机构消毒质量进行了监测。结果在2004-2008年连续5年,该区医疗机构消毒质量平均总合格率依次为93.52%、96.13%、96.79%、97.11%、96.94%。不同级别医疗机构消毒质量平均总合格率均达到95%以上。不同监测对象中,室内空气消毒质量合格率最低,仅为89.81%;最高为使用中消毒液,为99.44%。结论该区医疗机构消毒质量总体较好,需要对室内空气等薄弱环节加强消毒管理。     

在固相pH梯度4~7范围内海洛因成瘾者血浆蛋白质组分析(英文)

目的比较鉴定海洛因成瘾者和正常人血浆蛋白质组差异,为研究海洛因成瘾相关血浆蛋白提供线索。方法海洛因成瘾者(n=5)和正常对照者(n=5)血浆蛋白经剔除白蛋白和免疫球蛋白IgG后,以固相pH梯度4~7胶条等电聚焦为第一向,SDS聚丙烯酰胺凝胶电泳为第二向,进行蛋白双向电泳。图像分析软件Image Master Elit 5.0分析蛋白质2维图谱。手工挖取组间相差1.5倍的差异点,串联质谱分析鉴定。结果每张图谱平均检测到350±21个蛋白(亚基)斑点,其中5个蛋白点在2组图谱中差异1.5倍以上,鉴定结果分别为γ纤维蛋白原、人α1B糖蛋白、α1-抗胰蛋白酶原、视黄醇结合蛋白载体蛋白四聚体单体和铜蓝蛋白。结论海洛因成瘾者血浆与正常人血浆对比存在蛋白质组差异。某些差异蛋白可能与海洛因成瘾造成的神经损伤相关。     

As2 O3对人胃癌BGC-823 细胞端粒酶的影响

 目的 观察三氧化二砷（As₂ O₃）对人胃癌BGC-823细胞端粒酶活性及端粒酶逆转录酶基因转录的影响。方法 用不同浓度的三氧化二砷作用于人胃癌BGC-823细胞，通过MTT法测定细胞活力；流式细胞术检测细胞凋亡变化；TRAP PCR ELIsA方法检测细胞端粒酶活性的变化；RT-PCR半定量方法检测细胞端粒酶hTEI汀基因mRNA的转录水平。结果 三氧化二砷可明显抑制人胃癌BGC-823细胞的生长，诱导细胞发生凋亡，抑制作用随三氧化二砷浓度的升高及作用时间的延长而增强。细胞的端粒酶活性明显下降，细胞hTERT基因的转录表达显著抑制。BGC-823细胞端粒酶活性的下调与As₂ O₃作用时间和浓度有关，呈现明显的时间-剂量效应关系。结论 As₂ O₃能够抑制人胃癌BGC-823细胞的增殖、促使细胞凋亡、抑制细胞的端粒酶活性。As₂ O₃是一种良好的端粒酶抑制剂，在肿瘤的治疗中具有一定应用价值。     

水中微囊藻毒素的定量酶联免疫法研究

目的建立高灵敏度的水中微囊藻毒素的酶联免疫吸附试验（ELISA）方法。方法使用微囊藻毒素检测试剂盒,利用抗原与抗体间免疫化学反应,进行定量。结果微囊藻毒素在0.1～2.0μg/L范围内呈线性,标准曲线相关系数-0.995～-0.999。向样品中分别添加0.3、0.7、1.5μg/L 3个水平的微囊藻毒素,平均回收率分别为77.8%、85.7%和90.0%,相对标准偏差6.5%。结论该方法灵敏度高,适合水中痕量微囊藻毒素检测,并可实现大批量样品的筛选。