超高效液相色谱-串联质谱测定尿中14种β-内酰胺类抗生素残留

目的 建立测定尿液中14种β-内酰胺类抗生素残留的超高效液相色谱-串联质谱分析方法。 方法 尿液经酶解后,Oasis PRiME HLB(200 mg,6 ml)固相萃取柱净化,采用Waters BEH C18色谱柱(2.1 mm×100 mm, 1.7 μm),0.01 mol/L乙酸铵的水-甲醇作为流动相进行梯度洗脱,电喷雾离子源电离,正离子扫描,多反应监测模式进行定性和定量分析。 结果 阿莫西林和头孢曲松的线性范围为10～1 000 ng/ml,其余12种β-内酰胺类抗生素为5～1 000 ng/ml,相关系数均大于0.99。阿莫西林和头孢曲松的定量限为10 ng/ml,其余的方法定量下限为5 ng/ml,检出限为0.5～2.9 ng/ml,3个加标水平下的回收率为79.8%～97.9%,相对标准偏差为2.1%～11.9%。 结论 该方法操作简便、具有较高的灵敏度、特异度和精确性,适用于尿中痕量14种β-内酰胺类抗生素残留量的测定。     

基于计划行为理论的吸烟男性影响戒烟行为的因素探索

目的尝试运用计划行为理论建立吸烟男性影响戒烟行为的因素理论模型,为有针对性地开展吸烟男性戒烟干预提供依据。方法采用分层整群随机抽样的方法对200名15岁~69岁的上海市浦东新区吸烟男性进行问卷调查,建立吸烟男性影响戒烟行为的理论模型,运用Logistic回归模型进行单因素和多因素分析验证,确定相关危险因素以及干预策略。结果本次调查中,有戒烟意愿的吸烟男性占23.5%;曾经尝试戒烟的占12.0%。本次调查问卷中涉及的行为信念、规范信念和知觉行为控制等因素均为相关危险因素,且有统计学意义。结论本次调查中计划行为理论在吸烟男性戒烟行为的影响因素模型中得以初步建立和验证。本次研究提示:对于吸烟男性戒烟的干预应该从简单的知信行转变为从行为信念、规范信念、知觉行为控制等方面进行针对性干预。     

乙型肝炎病毒变异在母婴传播中的初步研究

目的 探索肝细胞癌相关乙肝病毒变异在母婴传播和婴儿慢性感染中变化规律,为肝细胞癌的防控提供理论支撑。方法 将413名HBV表面抗原(HBsAg)阳性产妇及其新生儿纳入本研究。应用定量PCR检测产妇外周血和新生儿脐带血HBV DNA,应用套式PCR和克隆测序方法测定前S区和核心启动子区的HCC相关HBV变异。出生经标准HBV免疫,7个月后对104名婴儿HBV感染情况进行成功随访,对外周血HBV DNA阳性婴儿测定HCC相关HBV变异发生情况。结果 在413名新生儿中,41名(9.9%)新生儿HBV DNA水平≥10₃ copies/mL。随访到104名婴儿中,4名(占3.8%)HBV DNA≥10₃ copies/mL。与未发生HBV跨胎盘传播的产妇相比,发生HBV跨胎盘传播者外周血HBV核心启动子变异没有增加,但在C2基因亚型的前S区中,T2898G/C, C3000T, C3116T, T31C和T52C变异显著增加HBV跨胎盘传播的风险。HBV基因组中前S区和核心启动子区的HCC相关变异的频率在产妇外周血和新生儿脐带血中无明显差别,但是在母婴传播的7月龄HBV DNA阳性婴儿中,这些变异几乎不存在。结论 HBV C2基因亚型的前S区某些变异可能影响HBV跨胎盘传播,但是HCC相关HBV变异准种并没有造成婴儿慢性感染的优势,促进HBV致癌的变异体是在漫长的慢性感染过程中逐渐被选择出来的。     

一例HIV抗体蛋白免疫印迹法检测条带不全病例的分析

目的通过对最近一例艾滋病病毒(HIV)抗体实验室检测"不确定"结果的分析讨论,尽可能减少实验室"不确定"结果的比例,提高实验室HIV确证实验的质量。方法该病例的血清标本采用两种酶联免疫吸附试验(ELISA)及两种快诊实验检测,又用蛋白免疫印迹法(WB)进行确证实验,并结合流行病学资料、核酸检测和基因测序结果,对该样本进行全面分析。结果 2012年11月至2013年3月期间,一例首次来自上海市肺科医院,两次随访均来自浦东新区自愿咨询检测门诊(VCT)的病例,ELISA和快诊检测为HIV抗体阳性,但WB确证结果首次为"不确定",第2、第3次随访结果也均为"不确定",后经核酸检测结果为阳性,基因测序结果为HIV-1型的CRF01_AE重组亚型,符合该病例的流行病学调查资料。结论对确证试验为"不确定"的病例,应综合初筛结果和实验室辅助检测手段及流行病学史,尽早明确个体HIV感染情况。     

两种梅毒血清学检测方法的联合运用分析

目的进一步提高酶联免疫吸附试验(ELISA)对梅毒的筛查率,确保梅毒血清学的检测效果。方法采用ELISA联合甲苯胺红不加热血清试验(TRUST),对2011年上海浦东新区2 686例监测人群的血清样本进行梅毒血清学筛查,联合检测的血清学阳性样本用梅毒螺旋体明胶凝集试验(TPPA)甄别其生物学假阳性;再从2 397份两种方法均为阴性的样本中,随机抽取1 000份进行TPPA检测,甄别其生物学假阴性。结果 ELISA法相对于TPPA法的敏感性为98.9%,特异性为98.4%,两法间差异无统计学意义(P>0.05);ELISA与TRUST法联合应用后的敏感性接近100%,特异性为98.3%。结论 ELISA与TRUST方法的联合应用,其敏感性接近100%,表明其可用于梅毒筛查;另一方面,两者联合运用的特异性为98.3%,具有一定的假阳性率,表明其阳性样本(两法均为阳性的样本除外)还需应用TPPA方法进行最终确认。     

Genetic Diversity,Antibiotic Resistance,and Pathogenicity of Aeromonas Species from Food Products in Shanghai,China

ObjectiveAeromonas has recently been recognized as an emerging human pathogen. Aeromonas-associated diarrhea is a phenomenon occurring worldwide. This study was designed to determine the prevalence, genetic diversity, antibiotic resistance, and pathogenicity of Aeromonas strains isolated from food products in Shanghai.MethodsAeromonas isolates (n = 79) collected from food samples were analyzed using concatenated gyrB-cpn60 sequencing. The antibiotic resistance of these isolates was determined using antimicrobial susceptibility testing. Pathogenicity was assessed using β-hemolytic, extracellular protease, virulence gene detection, C. elegans liquid toxicity (LT), and cytotoxicity assays.ResultsEight different species were identified among the 79 isolates. The most prevalent Aeromonas species were A. veronii [62 (78.5%)], A. caviae [6 (7.6%)], A. dhakensis [3 (3.8%)], and A. salmonicida [3 (3.8%)]. The Aeromonas isolates were divided into 73 sequence types (STs), of which 65 were novel. The isolates were hemolytic (45.6%) and protease-positive (81.0%). The most prevalent virulence genes were act (73.4%), fla (69.6%), aexT (36.7%), and ascV (30.4%). The results of C. elegans LT and cytotoxicity assays revealed that A. dhakensis and A. hydrophila were more virulent than A. veronii, A. caviae, and A. bivalvium. Antibiotic resistance genes [tetE, blaTEM, tetA, qnrS, aac(6)-Ib, mcr-1, and mcr-3] were detected in the isolates. The multidrug-resistance rate of the Aeromonas isolates was 11.4%, and 93.7% of the Aeromonas isolates were resistant to cefazolin.ConclusionThe taxonomy, antibiotic resistance, and pathogenicity of different Aeromonas species varied. The Aeromonas isolates A. dhakensis and A. hydrophila were highly pathogenic, indicating that food-derived Aeromonas isolates are potential risks for public health and food safety. The monitoring of food quality and safety will result in better prevention and treatment strategies to control diarrhea illnesses in China.     

上海市浦东新区外来务工人员子女乙肝病毒感染及乙肝疫苗免疫状况调查研究

目的 研究外来务工人员子女乙肝病毒感染及乙肝疫苗免疫现况,为乙肝防治工作提供依据.方法 从上海市浦东新区5个城郊结合社区的幼儿园与中小学中招募1 071名外来务工人员子女开展流行病学问卷调查,采集静脉血进行乙肝血清学指标及HBV DNA浓度检测.结果 乙肝疫苗接种率87.1％(933/1 071),10岁以下学生接种率高于10岁及以上学生(P＜o.01),汉族接种率高于少数民族(P＜0.001),父母亲文化程度大专及以上学生的接种率高于父母亲文化程度高中及以下的学生(P＜0.001).HBsAg阳性率0.7％(7/1 071),年龄与家庭中有HBV感染亲属为HBsAg阳性的主要影响因素(P＜0.05);HBcAb阳性率1.7％(18/1 071),HBcAb阳性率与年龄呈正相关(P＜0.01);HBsAb阳性率为33.9％(363/1 071),3～14岁学生HBsAb阳性率随年龄增长而递减,15岁后再次升高(P＜0.001),少数民族学生阳性率高于汉族(P＜0.001).HBsAb滴度低水平比例随年龄增大而降低,正常水平与高水平比例随年龄增大而上升(P＜0.01).结论 外来务工人员子女乙肝疫苗接种率低于所在地户籍儿童,HBsAg、HBcAb阳性率较浦东新区2006年阳性率显著下降,建议进一步加强该人群的乙肝疫苗预防接种服务与管理.     

Effectiveness of post-exposure prophylaxis during varicella outbreaks among primary and middle school students in Shanghai: An analysis of three-year surveillance data

ObjectivesTo evaluate the effectiveness of post-exposure prophylaxis conducted during varicella outbreaks among students in Shanghai.MethodsSurveillance data were collected from September 1, 2013 to December 31, 2016 involving 3524 susceptible students in 109 primary and middle school classes where emergency vaccinations (EVs) had been administered. Students were divided into two groups according to their prior vaccination (PV) varicella vaccine status. A secondary attack rate was used to compare EV and non-EV groups using a chi-squared test. Stratification analyses were performed, adjusting for the EV administration date, the vaccination coverage rate, and the number of cases prior to the EV.ResultsThe effectiveness rate was 92.2% (95% confidence interval (CI): 37.1–99.0%) when EV was applied within 3 days following the outbreak onset date, and 95.2% (95% CI: 79.9–98.8%) when vaccination coverage was ≥80% among students with PV. When students with PV received an EV for varicella within 3 days, the effectiveness rate was 100%.ConclusionsEV showed high protective effectiveness for varicella during outbreaks, especially if administered within 3 days of an outbreak and in conjunction with a high coverage rate.