目的查明一起食源性疾病暴发事件的发生原因,为今后预防类似食源性疾病暴发事件提供依据。方法通过现场流行病学调查确定事件性质,查找可疑食物,通过卫生学调查发现可能污染环节,并采集可疑食物和病例样本进行实验室检测,判定致病因子...目的查明一起食源性疾病暴发事件的发生原因,为今后预防类似食源性疾病暴发事件提供依据。方法通过现场流行病学调查确定事件性质,查找可疑食物,通过卫生学调查发现可能污染环节,并采集可疑食物和病例样本进行实验室检测,判定致病因子。结果共发现28例病例,主要临床症状为腹泻、腹痛、恶心、呕吐。7例病例粪便样本分离到副溶血性弧菌(Vibrio parahaemolyticus,Vp),毒力因子检测均为耐热直接溶血素(thermostable direct hemolysin,TDH)阳性菌,PFGE结果显示其中6株菌株带型相似性系数为100.0%,完全同源。结论该事件为一起由副溶血性弧菌引起的食源性疾病暴发事件,可能原因为食物加工不彻底及交叉污染。建议加强餐饮业的原料、加工制作和服务等各个环节的食品安全监督管理,加强食品安全宣传,提高预防和控制食源性疾病的能力。展开更多
Background Elevated intraocular pressure （lOP） is primarily due to increased aqueous outflow resistance, but how aqueous outflow resistance is generated and regulated are still not fully understood. The aim of this ...Background Elevated intraocular pressure （lOP） is primarily due to increased aqueous outflow resistance, but how aqueous outflow resistance is generated and regulated are still not fully understood. The aim of this study is to determine whether changes in outflow facility, outflow pattern, and morphology following acute lOP elevation were reversible when the lOP was returned to a normal level in bovine eyes using a two-color tracer technique to label outflow patterns within the same eye. Methods Twelve fresh enucleated bovine eyes were perfused with Dulbecco＇s phosphate buffer saline （PBS） containing 5.5 mmol/L glucose （DBG） at 30 mmHg first to establish the baseline outflow facility followed by a fixed volume of red fluorescent microspheres （0.5 μm, 0.002% v/v）. After the red tracer being replaced with DBG in the anterior chamber, perfusion was continued at 7 mmHg with the same volume of green tracer, followed by a fixative. In two control groups, the eyes were constantly perfused at either 30 mmHg （n=6） or 7 mmHg （n=6） using the same methods. The outflow facility （C, pJ.min.-lmmHg-1）, was continuously recorded. Confocal images were taken along the inner wall （IW） of the aqueous plexus （AP） in frontal sections. The percent of the effective filtration length （PEFL, PEFL=IW length exhibiting tracer labeling/total length of IW） was measured. Sections with AP were processed and examined by light microscopy. The total length of IW and the length exhibiting separation （SL） in the juxtacanalicular connective tissue （JCT） were measured. A minimum of eight collector channel （CC） ostia per eye were analyzed for herniations. Results In the experimental （30-7 mmHg） group, the outflow facility was significantly higher at 7 mmHg （（4.81±1.33） #lmin-1 mmHg-1） than that at 30 mmHg （（0.99±0.15） μl.min-1 mmHg-1, P=-0.002）, corresponding to a significant increase in the PEFL （P=-0.0003）. The percent of CC ostia exhibiting herniations in the experimental group （（67.40±8.90） μl.min·-1mmHg-1） decreased significantly compared to that in the control at 30 mmHg （（94.44±3.33） μl.min-lmmHg-1, P=-0.03）, but higher than that in the control at 7 mmHg （（29.43±4.60） μl.min-1mmHg-1, P=0.01）. Washout-associated separation between the IW and JCT was found by light microscopy and percent separation length （PSL, PSL=SL/total length of IW） was decreased in the control at 30 mmHg compared to that in the experimental group and control at 7 mmHg. Conclusions The pressure-induced morphological and hydrodynamic changes were reversible. Changes （collapse of AP, separation between the JCT and IW, and herniation into CC ostia） influence the effective filtration area that regulates outflow facility.展开更多
文摘目的查明一起食源性疾病暴发事件的发生原因,为今后预防类似食源性疾病暴发事件提供依据。方法通过现场流行病学调查确定事件性质,查找可疑食物,通过卫生学调查发现可能污染环节,并采集可疑食物和病例样本进行实验室检测,判定致病因子。结果共发现28例病例,主要临床症状为腹泻、腹痛、恶心、呕吐。7例病例粪便样本分离到副溶血性弧菌(Vibrio parahaemolyticus,Vp),毒力因子检测均为耐热直接溶血素(thermostable direct hemolysin,TDH)阳性菌,PFGE结果显示其中6株菌株带型相似性系数为100.0%,完全同源。结论该事件为一起由副溶血性弧菌引起的食源性疾病暴发事件,可能原因为食物加工不彻底及交叉污染。建议加强餐饮业的原料、加工制作和服务等各个环节的食品安全监督管理,加强食品安全宣传,提高预防和控制食源性疾病的能力。
文摘Background Elevated intraocular pressure （lOP） is primarily due to increased aqueous outflow resistance, but how aqueous outflow resistance is generated and regulated are still not fully understood. The aim of this study is to determine whether changes in outflow facility, outflow pattern, and morphology following acute lOP elevation were reversible when the lOP was returned to a normal level in bovine eyes using a two-color tracer technique to label outflow patterns within the same eye. Methods Twelve fresh enucleated bovine eyes were perfused with Dulbecco＇s phosphate buffer saline （PBS） containing 5.5 mmol/L glucose （DBG） at 30 mmHg first to establish the baseline outflow facility followed by a fixed volume of red fluorescent microspheres （0.5 μm, 0.002% v/v）. After the red tracer being replaced with DBG in the anterior chamber, perfusion was continued at 7 mmHg with the same volume of green tracer, followed by a fixative. In two control groups, the eyes were constantly perfused at either 30 mmHg （n=6） or 7 mmHg （n=6） using the same methods. The outflow facility （C, pJ.min.-lmmHg-1）, was continuously recorded. Confocal images were taken along the inner wall （IW） of the aqueous plexus （AP） in frontal sections. The percent of the effective filtration length （PEFL, PEFL=IW length exhibiting tracer labeling/total length of IW） was measured. Sections with AP were processed and examined by light microscopy. The total length of IW and the length exhibiting separation （SL） in the juxtacanalicular connective tissue （JCT） were measured. A minimum of eight collector channel （CC） ostia per eye were analyzed for herniations. Results In the experimental （30-7 mmHg） group, the outflow facility was significantly higher at 7 mmHg （（4.81±1.33） #lmin-1 mmHg-1） than that at 30 mmHg （（0.99±0.15） μl.min-1 mmHg-1, P=-0.002）, corresponding to a significant increase in the PEFL （P=-0.0003）. The percent of CC ostia exhibiting herniations in the experimental group （（67.40±8.90） μl.min·-1mmHg-1） decreased significantly compared to that in the control at 30 mmHg （（94.44±3.33） μl.min-lmmHg-1, P=-0.03）, but higher than that in the control at 7 mmHg （（29.43±4.60） μl.min-1mmHg-1, P=0.01）. Washout-associated separation between the IW and JCT was found by light microscopy and percent separation length （PSL, PSL=SL/total length of IW） was decreased in the control at 30 mmHg compared to that in the experimental group and control at 7 mmHg. Conclusions The pressure-induced morphological and hydrodynamic changes were reversible. Changes （collapse of AP, separation between the JCT and IW, and herniation into CC ostia） influence the effective filtration area that regulates outflow facility.
