Dissemination of quinolone low-susceptible Haemophilus influenzae ST422 in Tokyo,Japan

IntroductionHaemophilus influenzae with a reduced susceptibility to quinolones (quinolone low-susceptible H. influenzae) has recently emerged in Japan. In addition, the regional outbreak of the quinolone low-susceptible H. influenzae ST422 clone has been reported. In this study, we isolated this clone from an acute care hospital located in a geographically different area from the previous outbreak and characterised the nature of this clone.MethodsEighty-nine H. influenzae isolated between 2017 and 2019 were tested. The antimicrobial susceptibility was determined by the broth dilution method. The genetic background was analysed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. Growth ability and β-lactamase acquisition were evaluated by growth curve analysis and conjugative transfer experiments, respectively.ResultsQuinolone low-susceptible isolates accounted for 4.2% (1/24) in 2018 and 13.9% (5/36) in 2019. Most of the quinolone low-susceptible strains (83.3%) were classified as ST422 and had amino acid substitutions in quinolone resistance-determining regions in both GyrA and ParC. The patients’ backgrounds were highly diverse. In addition, these isolates showed the same PFGE pattern as outbreak strains. The growth of ST422 clone was relatively faster than other clones. Furthermore, ST422 clone was able to acquire β-lactamase from a β-lactamase positive strain by horizontal transfer, becoming highly resistant to β-lactams.ConclusionOur study indicated that the quinolone low-susceptible H. influenzae ST422 clone has been spreading in the community undetected. In addition, this clone has the potential to grow faster and become more resistant through exogenous gene transfer. Therefore, ST422 clone should be monitored attention throughout Japan.     

日本血吸虫分泌蛋白基因Sjsp16的克隆与表达

目的　克隆和表达日本血吸虫新的分泌蛋白Sjsp16的编码基因。　 方法　根据EST测序的结果设计引物 ,从含有Sjsp16基因的cDNA克隆中扩增得到该编码基因 ,亚克隆入原核表达载体 pET2 8中表达 ,然后用生物信息学的方法对蛋白结构功能进行预测。　结果　成功克隆和表达了日本血吸虫分泌蛋白基因Sjsp16,生物信息学分析提示该基因编码蛋白的N端带有一个信号肽序列 ,是一个分泌蛋白 ,含有一个ML功能结构域 ,具有 4种潜在的功能作用位点 ,即 1个N 糖基化位点、3个蛋白激酶C磷酸化位点、4个酪蛋白激酶Ⅱ磷酸化位点和 3个肉豆蔻酰化位点。　结论　Sjsp16基因编码蛋白为具有脂质识别和结合功能的分泌蛋白 ,可能为潜在的血吸虫病药物靶点或疫苗候选分子。     

贵州省从江县疟疾局部暴发的影响因素分析

目的 为确定2006年7月贵州省从江县局部疟疾暴发的影响因素。 方法 在疟疾暴发点进行流行病学调查，对495名常住居民采集滤纸干血滴，用间接荧光抗体试验（IFAT）检测人群抗体水平。对其中423人进行问卷调查，内容包括两年内疟史、疟防知识知晓情况、蚊帐使用情况、露宿习惯等。收集乡卫生院门诊发热病人登记资料，分析发热病人就医行为。复查上报的42例疟疾病例阳性血片和同期普查的部分阴性血片。按蚊调查仅做半通宵人饵诱捕和人、牛房密度调查，分析该地传播媒介组成和叮人率等。 结果 42张阳性血片经复查确定12张阳性均为间日疟原虫，18 d的疟疾罹患率为2.1%(16/753，包括4例临床诊断病例）。居民平均荧光抗体阳性率为8.7%（43/495），阳性几何平均滴度倒数（GMRT）为20.6，总的GMRT为10.6，其中5岁以下组抗体阳性率为7.5%（3/40），阳性GMRT为25.1。发热病人就诊率为81.3%（118/145），平均发热后3.9 d就诊。疟防知识知晓率平均为25.5%（108/423），文盲组、小学组和中学组分别为17.1%、29.2%和40.0%，组间差异有统计学意义（P＜0.01）。蚊帐使用率平均为31.0%（131/423），露宿率平均为40.7%（172/423）。2004和2005年休根治疗率分别为68.2%（15/22）和48.3%（14/29）。当地传疟媒介除中华按蚊外还存在嗜人按蚊和微小按蚊，人房帐内捕获嗜人按蚊和微小按蚊，叮人率分别为0.0566和0.0755。 结论 当地存在我国重要传疟媒介，因灾后居民居住条件简陋，自我保护意识薄弱，且有露宿习惯，疟疾病例的发现和治疗均不及时等，是促成了该起疟疾暴发的主要原因。     

Study of the 49 kDa excretory-secretory protein gene of <Emphasis Type="Italic">Trichinella nativa</Emphasis> and <Emphasis Type="Italic">Trichinella spiralis</Emphasis>

Summary To study the function of the 49 kDa excretory-secretory (ES) protein gene (P49) of Trichinella, the genes was amplified by RT-PCR from RNA of Trichinella spiralis and Trichinella nativa and several Chinese Trichinella isolates of domestic animals, and sequenced after being cloned. The amplified products of these parasites produced bands of about 950 bp. The 97.2 % to 100 % nucleotides identity and 94.3 % to 100 % identity of deduced amino acids among P49 gene of these Trichinella strains showed the close relationship of these parasites. The P49 gene of T. nativa was cloned into the BamHI site of the prokaryotic expression vector pET-30a, and the recombinant vector was expressed. The expressed product was 40.8 kDa in size. In Western blot analysis, the expressed product was reactive to sera of mice infected with T. nativa, T. spiralis and their Chinese geographical strains.     

Schistosomiasis in a migrating population in the lake region of China and its potential impact on control operation

Coverage of migrating people in schistosomiasis control program is a growing concern in China. Schistosomiasis caused by Schistosoma japonicum is still one of the major infectious diseases of public health importance in China though tremendous efforts have been made to control the transmission over the past decades. Along with the rapid social-economic development, migrant population has been remarkably increasing across the country. The infected migrants may introduce a new souse of infection to endemic areas or the areas where the transmission had been controlled or interrupted but the intermediate host Oncomelania snail is still present. Preliminary studies for surveillance on schistosomiasis prevalence in migrants were reported, but there is little basic information provided. We carried out an investigation on the prevalence in immigrants, emigrants and permanent residents in three villages of Hunan province located in the main endemic area of lake region, and analyzed the potential impact of migration on control practice. In the study villages, the migrant population accounts for 53.6% of the total. Schistosoma infection was detected by modified Kato-Katz method and miracidium hatching test. Questionnaire survey was conducted comprising knowledge of disease and its transmission, water contact, personal protective measures, and whether examined and treated after water contact. The survey indicated that the migrants and permanent residents had similar life style, and the majority of them experienced water contact in agricultural work or routine life activities. However, the infection rate in immigrants was significantly higher than that in permanent residents. It was also found that the migrants had significantly less knowledge about the disease than the permanent residents, and took no personal protective measures. This is due to that the control program could not cover the migrants when they were absent at the time the program being implemented. The present study suggested that the surveillance and intervention for migrants, immigrants in particular, should be included and strengthened in schistosomiasis control program and a feasible scheme be developed.     

Does DRD2 polymorphism influence the clinical characteristics of prolactinoma?

ObjectivesGenetic alterations explaining the clinical variability of prolactinomas still could not be clarified and dopamine D2 receptor (DRD2) polymorphism is a putative candidate for the variable response to dopaminergic treatment. The present study was conducted to investigate the influence of DRD2 TaqI A polymorphism on initial and follow-up characteristics of prolactinoma.Patients and methodsSeventy-two patients with prolactinoma and 98 age and gender matched control subjects were recruited to the case-control study. Serum prolactin levels were assessed by enzyme-linked immunosorbent assay and DRD2 polymorphism was determined by polymerase chain reaction and restriction length polymorphism analysis.ResultsDecrease of prolactin levels and the tumor shrinkage after cabergoline treatment were 93.9 ± 5.9% and 58.3 ± 33.1% in microadenomas and 96.1 ± 6.1% and 51.7 ± 29.3 in macroadenomas (P = 0.02 and P > 0.05, respectively). We observed no significant difference for DRD2 genotypes and the alleles between the patients and healthy group (P > 0.05). Prolactin levels before treatment were correlated with tumor diameter before and after treatment and the percentage of prolactin decrease with treatment (P < 0.001 r = 0.58, P < 0.001 r = 0.40 and P < 0.001 r = 0.47, respectively). Tumor diameter before the treatment was also correlated with the tumor diameter after the treatment (P < 0.001 r = 0.64) and the percentage of prolactin decrease (P = 0.01 r = 0.30). However, no significant association was found between characteristics of prolactinoma and DRD2 genotypes and alleles (P > 0.05).ConclusionThis study revealed that DRD2 TaqI A receptor polymorphism was not associated with the development of prolactinoma and its clinical characteristics. Future studies are needed to clarify the clinical implications of genetic alterations in prolactinoma.     

Negative Association of Domestic Activity and Active Commuting with Metabolic Syndrome in a Chinese Population Aged 35-64 Years

Objective To understand the associations of physical activity domains with metabolic syndrome among a middle-aged Chinese population.
Methods In all, 3326 professional adults aged 35-64 years from Beijing and Zhejiang province were recruited with a cluster random sampling method. The Global Physical Activity Questionnaire was modified, and the recommended Asia-Pacific cut-offs of waist circumstance were introduced into the criteria for metabolic syndrome from the Adult Treatment Panel III. A binary logistic regression model was applied to examine the association of all physical activity domains with the risk of the syndrome.
Results Participants who engaged in domestic activity for 31176 MET-min/week had a 41.6% less chance of having metabolic syndrome [odds ratio (OR), 0.584;95%confidence interval (CI), 0.480-0.710] than those without this activity. In adjusted models, adults who actively commuted for 333 MET-min/week but<528 MET-min/week had a 25%less chance of having the syndrome (OR, 0.750;95%CI, 0.582-0.966) than those who did not. No interaction was detected between the two domains of activity and the syndrome.
Conclusion This study highlighted the independently negative association of traffic and house activity with the prevalence of the syndrome in this sample with a generally low level of moderate activity.     

耐多药结核分枝杆菌中embB基因突变与乙胺丁醇耐药的相关性研究

目的 研究耐多药结核分枝菌中embB基因突变与乙胺丁醇耐药的相关性. 方法 比例法检测84株耐多药结核分枝杆菌的乙胺丁醇(EMB)耐药性,基因测序检测embB基因的突变,2检验分析二者之间的相关性. 结果 84株耐多药结核分枝杆菌中有43株(51.2%)对EMB耐药,41株(48.8%)对EMB敏感,57株耐多药菌株(67.9%)的embB基因发生突变.在43株EMB耐药菌株中,embB基因突变的菌株为40株(93.0%),而41株EMB敏感菌株中,embB基因突变的菌株为17株(41.5%),embB基因在耐药菌株中的突变频率远高于敏感菌株(2=25.58,P=0.00).embB306是最常见的突变位点,其在耐药菌株的突变率也高于敏感菌株(2=12.37,P=0.00),embB基因和embB306位点检测EMB耐药的敏感度、特异度和准确性分别为93.0%和65.1%,58.5%和73.2%,76.2%和69.0%. 结论 EMB耐药的产生与embB基因和embB306突变有关,二者用于检测EMB耐药有一定的参考意义.     

Abdominal Obesity and Its Attribution to All-cause Mortality in the General Population with 14 Years Follow-up: Findings from Shanxi Cohort in China

Objective This study aimed to assess the association of waist circumference(WC) with all-cause mortality among Chinese adults.Methods The baseline data were from Shanxi Province of 2002 China Nutrition and Health Survey. The death investigation and follow-up visit were conducted from December 2015 to March 2016. The visits covered up to 5,360 of 7,007 participants, representing a response rate of 76.5%. The Cox regression model and floating absolute risk were used to estimate hazard ratio and 95% floating CI of death by gender and age groups(≥ 60 and 60 years old). Sensitivity analysis was performed by excluding current smokers; participants with stroke, hypertension, and diabetes; participants who accidentally died; and participants who died during the first 2 years of follow-up.Results This study followed 67,129 person-years for 12.5 years on average, including 615 deaths. The mortality density was 916 per 100,000 person-years. Low WC was associated with all-cause mortality among men. Multifactor-adjusted hazard ratios(HR) were 1.60(1.35–1.90) for WC 75.0 cm and 1.40(1.11–1.76) for WC ranging from 75.0 cm to 79.9 cm. Low WC( 70.0 cm and 70.0–74.9 cm) and high WC(≥ 95.0 cm) groups had a high risk of mortality among women. The adjusted HRs of death were 1.43(1.11–1.83), 1.39(1.05–1.84), and 1.91(1.13–3.22).Conclusion WC was an important predictor of death independent of body mass index(BMI). WC should be used as a simple rapid screening and predictive indicator of the risk of death.     

Genetic Diversity,Antimicrobial Resistance,and Virulence Genes of Aeromonas Isolates from Clinical Patients,Tap Water Systems,and Food

Objective This study aimed to evaluate the genetic diversity, virulence, and antimicrobial resistance of Aeromonas isolates from clinical patients, tap water systems, and food.Methods Ninety Aeromonas isolates were obtained from Ma'anshan, Anhui province, China, and subjected to multi-locus sequence typing(MLST) with six housekeeping genes. Their taxonomy was investigated using concatenated gyr B-cpn60 sequences, while their resistance to 12 antibiotics was evaluated. Ten putative virulence factors and several resistance genes were identified by PCR and sequencing.Results The 90 Aeromonas isolates were divided into 84 sequence types, 80 of which were novel,indicating high genetic diversity. The Aeromonas isolates were classified into eight different species. PCR assays identified virulence genes in the isolates, with the enterotoxin and hemolysin genes act, aer A, alt,and ast found in 47(52.2%), 13(14.4%), 22(24.4%), and 12(13.3%) of the isolates, respectively. The majority of the isolates(≥ 90%) were susceptible to aztreonam, imipenem, cefepime, chloramphenicol,gentamicin, tetracycline, and ciprofloxacin. However, several resistance genes were detected in the isolates, as well as a new mcr-3 variant.Conclusions Sequence type, virulence properties, and antibiotic resistance vary in Aeromonas isolates from clinical patients, tap water systems, and food.