液态低温冷藏血吸虫卵孵化实验初探

目的观察液态冷藏血吸虫卵的活性,为规范血吸虫卵孵化法提供阳性参考品。方法人工获取家兔血吸虫肝卵,保存1．2％的NaCl溶液,冰箱4oC冷藏,观察血吸虫卵存活时间和孵化活性;观察不同温度保存血吸虫卵孵化活性;比较不同地区的自来水孵化血吸虫卵的效果。结果液态低温冷藏保存25周虫卵能孵出毛蚴,第9周时孵化出的毛蚴数量开始明显减少,活力明显减弱。保存温度4℃5d均能孵出,18℃4d能孵出,25oC3d能孵出,30oCld后即不能孵出。不同地区水的pH6．4～7．1之间,脱氯水余氯含量0．02～0．05ppm之间,新鲜自来水余氯含量0．05—0．27ppm之间,均孵出毛蚴。结论液态低温冷藏血吸虫卵可以保持较长的活性,可以建立血吸虫孵化质控参考品。     

一起生饮羊奶引起的布鲁氏病暴发疫情调查

目的 调查处置一起由食用新鲜“羊初乳”导致的布鲁氏菌病(布病)暴发疫情,为科学开展食源性布病疫情的预防控制提供依据。方法 采用布病个案调查表,对医院报告病例开展流行病学调查,再根据调查线索通过“滚雪球”的方式进行可疑病例搜索调查和实验室采样检测,运用描述性流行病学方法对资料进行分析。结果 本起疫情共确诊6例布病病例,均为同一日在某乳制品公司现场饮用新鲜“羊初乳”的同一参观团人员,罹患率高达50.00%(6/12)。结论 综合病例临床表现、流行病学调查以及实验室检测结果,确定本起疫情为布病暴发疫情,引起原因为生饮未经消毒的羊奶。疫情提示牛、羊等奶制品需加强监管,降低布病发病风险。     

Field Evaluation of a PCR Test for Schistosoma japonicum Egg Detection in Low-Prevalence Regions of China

Sensitive Schistosoma japonicum detection methods are needed to progress from schistosomiasis control to elimination. The sensitivity of the Kato-Katz thick smear and miracidium hatching tests decrease with infection intensity and serological tests cannot always identify current infections. We evaluated a fecal polymerase chain reaction (PCR) assay to detect S. japonicum infection in 106 humans and 8 bovines in China. PCR was highly sensitive, detecting S. japonicum DNA at 0.5 eggs/g of stool. Comparing PCR examination of a single stool sample to the miracidium hatching test using three consecutive stool samples, more humans were hatching test positive (20%) than PCR positive (15%). However, two individuals were PCR positive in a village where no infections were detected by coprological methods. The sensitivity of PCR makes it a promising tool for schistosomiasis diagnostics and screening, although egg shedding variability and stool sample size present challenges for any detection method in low-transmission areas.     

2005-2010年丹棱县血吸虫病监测疫情分析

目的了解丹棱县血吸虫病流行情况,为制定血吸虫病防治策略和评价防治效果提供科学依据。方法分析2005-2010年在四川省丹棱县双桥镇桂香村开展血吸虫病疫情监测的资料。结果 2005-2010年,检查村民602、603、631、615、601、564人,感染人数为9、9、6、5、0、0人,感染率分别为1.50%、1.49%、0.95%、0.81%、0.00%和0.00%。其中,20岁以下年龄组1例;2005-2008年20～49岁组检查318、325、341、336人,阳性3、7、4、4人,50～岁组检查159、173、188、173人,阳性5、2、2、1人;2009和2010年未粪检出阳性;未发现急性和晚期血吸虫病患者。每年检查全部耕牛9、3、3、4、4、0头,未发现阳性。各年有螺面积分别为49 660、42130、54 130、543 30、51 440、51 390 m2,活螺密度为2.38、1.09、1.52、1.51、1.49和1.29只/0.11m2,未发现新发螺面和感染性钉螺。结论丹棱县人群血吸虫感染者主要分布成年人中,50岁以上人群感染率较高,应作为重点关注对象;"以传染源控制为主"的综合措施成效显著,应通过多部门的合作,提高科学防治、综合治理血吸虫病的能力。     

2011年四川省巴塘县鼠疫自然疫源地调查结果分析

目的证实巴塘县是否存在喜马拉雅旱獭鼠疫自然疫源地,为四川省鼠疫防治提供科学依据。方法对巴塘县进行鼠疫流行病学调查,同时进行实验室检测。结果细菌培养自毙喜马拉雅旱獭1份,分离鼠疫菌1株;胶体金检测牧犬血清52份,阳性血清12份,阳性率为23.08%;间接血凝试验(IHA)检测牧犬血清52份,阳性血清10份,最高滴度为1∶40 960,阳性率19.23%;反向血凝试验(RIHA)检测反向血液1份,其滴度为1∶12 800。结论四川省巴塘县为喜马拉雅旱獭鼠疫自然疫源地,并且动物间鼠疫正在流行,做好鼠疫防治工作,防止人间鼠疫的发生。     

囊型包虫病流行区犬只细粒棘球绦虫感染季节性规律研究

目的了解犬只感染细粒棘球绦虫(Eg)的时间规律,探索更加易行的犬驱虫策略。方法采取整群抽样的方法,在马尔康和松潘各抽取了1个乡,初始纳入398只犬,使用吡喹酮进行每3个月1次的驱虫,ELISA检测驱虫前犬粪感染情况。结果在3月和6月连续两次驱虫后,9月两县犬只感染水平已分别降至1.25%和1.18%,下降率分别为94.21%和91.23%。但在12月,犬只感染率大幅却上升。犬只感染主要发生在9月至次年3月。原因可能是初冬(11、12月)是屠宰季节,而初春时寒冷及草料缺乏导致牲畜大量死亡,犬进食较多感染性内脏,从而导致感染机会大幅增加。结论马尔康县初冬、初春为主要感染季节,松潘主要感染季节为冬季;应根据实际感染季节有针对性地优化防治策略。     

Co-exposure of cadmium and lead on bone health in a southwestern Chinese population aged 40-75 years

Both cadmium (Cd) and lead (Pb) are associated with bone health, but studies exploring the effects of Cd and Pb co-exposure on bone health are rare. This study aimed to assess the interactive effects of Cd and Pb co-exposure on bone health. In total, 799 participants, living in the targeted areas (located in southwestern China) for more than 15 years, aged 40-75 years, and subsisted on homegrown rice and vegetables were investigated. Cd and Pb levels in urine and blood samples, as well as bone mineral density, T- and Z-score were determined. After being adjusted for covariates, the T-score was negatively correlated with blood Pb in men (P < .05); for women and non-smoking women, the T-score was negatively correlated with urinary Pb (P < .05). Moreover, after being adjusted for covariates, the Z-score was negatively correlated with urinary Pb in non-smoking women (P < .05). No positive association of prevalence of osteoporosis with Cd and Pb exposure was found. However, at an additive scale, positive interactions of urinary Cd and Pb on the prevalence of osteoporosis for women and non-smoking women, and the same interactions to blood Cd and Pb for men were found. There was also a positive interaction of urinary Cd and Pb for women at a multiplicative scale. This study suggests Cd and Pb exposure could exert detrimental effects on bone health, with possible underlying interactions. Nevertheless, more studies are needed to explore the interactive effects of heavy metal co-exposure.     

中国成年双生子高脂血症的分布特征

目的描述中国双生子登记系统(CNTR)成年双生子高脂血症的分布特征, 初步探索遗传和环境因素对高脂血症的影响。方法研究对象来自CNTR在全国11个项目地区募集的双生子, 纳入成年且具有高脂血症信息的69 130名(34 565对)双生子进行分析。采用随机效应模型描述高脂血症的人群、地区分布特征。分别计算不同卵型双生子的高脂血症同病率, 估算遗传度。结果研究对象年龄为(34.2±12.4)岁。双生子人群高脂血症患病率为1.3%(895/69 130)。男性、年长、城镇、已婚、大专及以上文化程度、超重、肥胖、体力活动不足、当前吸烟和曾经吸烟、当前饮酒和曾经饮酒人群中高脂血症患病率较高。双生子对内分析发现, 同卵双生子高脂血症同病率为29.1%(118/405), 高于异卵双生子的18.1%(57/315), 差异有统计学意义(P<0.05)。在不同年龄、地区及性别分层中, 同卵双生子同病率仍呈现高于异卵双生子的趋势。进一步同性别双生子对内分析发现, 在北方组和女性组中, 高脂血症遗传度分别为13.04%(95%CI:2.61%～23.47%)、18.59%(95%CI:4.43%～3...     

A allele of SNP12 in <Emphasis Type="Italic">estrogen receptor 1</Emphasis> was a risk factor for cryptorchidism in Asians: a systematic review with meta-analysis and trial sequential analysis

Objective

Some studies have been carried out to evaluate the association between SNP12 in estrogen receptor 1 and cryptorchidism, but the results remain inconsistent. We carried out a meta-analysis to explore the association between this polymorphism and cryptorchidism risk.

Methods

All eligible studies were searched in PubMed, Web of Science, Embase and Cochrane Library. Pooled odds ratios, with 95 % confidence intervals, were assessed for the association using fixed- and random-effects models.

Results

Overall, four case–control studies (363 cases, 415 controls) were included in the meta-analysis. No significant publication bias (P _Begg = 0.308, P _Egger = 0.288) was found. A allele of SNP12 in estrogen receptor 1 was protective factor to cryptorchidism in allele model, dominant genetic model and heterozygote comparison in Caucasians, but the result was turned out to be false positive by trial sequential analysis. However, A in allele model was risk factor to cryptorchidism in Asians (odds ratio 2.02, 95 % confidence interval 1.03–3.01, p = 0.946 for heterogeneity) and the result was turned out to be true positive by trial sequential analysis, even though there were merely two original studies.

Conclusions

The results of this meta-analysis suggest that A allele of SNP12 in estrogen receptor 1 may increase the risk of cryptorchidism in Asians. Meanwhile, further well-designed studies with large sample sizes are required to confirm the present findings, especially in Caucasians.

     

The Survey ofCronobacterspp. (formerlyEnterbacter sakazakii) in Infant and Follow-up Powdered Formula in China in 2012

ObjectiveTo determineCronobacterspp.contamination in infant and follow-up powdered formula in China. MethodsAll of 2282 samples were collected from theretailmarkets in China from January 2012 to December 2012, and analyzed forCronobacter spp.by theChineseNationalFood Safety Standard. Characterization of the isolates was analyzed by pulsed-field gel electrophoresis (PFGE) withXbaI and SpeI restriction enzymes. ResultsCronobacterspp. strains were isolated from 25 samples, and the positive rates ininfant powdered formulas and follow-up powdered formulas were 0.90% (10/1011) and 1.18% (15/1271), respectively. Analysis of variable data regarding different purchasing store formats, seasonality, and production locations as well as comparison of infant versus follow-up formulas did not reveal statistically significant factors. During the sampling period, one of six surveillance zones did exhibit a statistically significant trend towards higher positive rate. PFGE characterization ofCronobacterspp.to elucidate genetic diversity revealed only three pairs ofCronobacterspp.out of 25 having the same PFGE patterns. ConclusionThe current investigation indicated a lower positive rate ofCronobacterspp.in the powdered formula in China.This evidence suggested contamination originating from multiple different sources during the manufacturing process.