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1.
Diarrhoea, the most common disease directly related to water, sanitation, and hygiene (WASH), still remains one of the most significant health problems among children under-five worldwide. In this reality, BRAC, the largest NGO in the world initiated a comprehensive WASH intervention in 50 upazilas (sub-districts) of Bangladesh in 2007 which was later scaled up to cover 150 upazilas in two subsequent phases. The intervention period of the programme was 2007–2011.The present study encompassed 30 upazilas of the first phase of intervention. The aim of the study was to investigate the effectiveness of this intervention on reduction of diarrhoea among under-five children, and to identify the factors associated with childhood diarrhoea. A repeated cross-sectional study design was followed, and a population-based survey was carried out on four occasions: baseline (2007), midline (2009), endline (2011), and post-endline (2015) among 4,775 households. This analysis considers only households having at least one under-five children.Absence of handwashing practice with soap after defecation and before eating food, unclean latrine condition, and unsafe disposal of child faeces were identified as significant risk factors associated with under-five diarrhoea from Log-binomial regression. The prevalence of under-five diarrhoea within the past 2 weeks of the survey declined from 13.7% at baseline to 3.6% at end-line (p < 0.001) in the WASH intervention area. However, the progress seemingly stalled after 2011, which may have occurred due to the lack of improvement in unsafe disposal of child faeces and unclean latrine condition after the intervention period.Study findings suggest that, to reduce the prevalence of childhood diarrhoea it is important to promote safe disposal of child faeces, maintaining cleanliness of latrines, and washing hand with soap at critical times, beyond merely increasing the sanitation coverage. Findings also underline the necessity of maintaining a small-scale monitoring component involving local community, such as a WatSan committee (a local committee comprising the user communities for supervising WASH related activities) for periodic monitoring at household level for a certain period after the program intervention works to make the behavioural change more sustainable and to keep the reduction rate of under-five diarrhoeal prevalence steady.  相似文献   
2.
目的 探讨不同剂量栀子苷对大鼠肝脏的毒性,以及对其血清、肝组织及粪便中胆汁酸的影响。方法 60只SD大鼠,雌雄各半,按体质量随机分成空白组及栀子苷(50,100,200,400 mg·kg-1)组,共5组,每组12只,每天灌胃给药1次,连续7 d,于第8天收集大鼠血清、肝组织和盲肠内容物。检测各组大鼠血清丙氨酸氨基转移酶(ALT),门冬氨酸氨基转移酶(AST),碱性磷酸酶(ALP)活性,白蛋白(ALB),总胆红素(TBIL),总胆汁酸(TBA),肌酐(Crea),尿素(Urea)含量,肝脏组织切片分别作苏木素-伊红(HE)染色,免疫组化检测细胞角蛋白7(CK7),细胞角蛋白19(CK19)蛋白表达,蛋白免疫印迹法(Western blot)测定肝组织CK7,CK19蛋白表达,实时荧光定量聚合酶链式反应(Real-time PCR)检测胆固醇7α-羟化酶(CYP7A1),胆固醇27α-羟化酶(CYP27A1),胆固醇12α-羟化酶(CYP8B1) mRNA表达情况,采用超高效液相色谱-串联质谱(UPLC-MS)测定血清、肝脏及盲肠内容物中18种胆汁酸含量。结果 与空白组比较,各剂量栀子苷组TBIL水平显著升高(P<0.01);400 mg·kg-1栀子苷组ALT,AST活性和TBA含量明显升高(P<0.05,P<0.01);HE染色表明,与空白组比较,栀子苷200,400 mg·kg-1组肝组织的汇管区有胆管反应,胆管周围有炎症细胞的浸润,尤以栀子苷400 mg·kg-1毒性明显。栀子苷400 mg·kg-1栀子苷组肝组织中CK7,CK19表达较空白组明显增加(P<0.05,P<0.01)。与空白组比较,400 mg·kg-1栀子苷组肝组织中甘氨熊脱氧胆酸(GUDCA),甘氨猪去氧胆酸(GHDCA)含量明显下降(P<0.05,P<0.01),牛磺鹅去氧胆酸(TCDCA),猪去氧胆酸(HDCA),胆酸(CA),鹅去氧胆酸(CDCA)含量显著升高(P<0.01),甘氨胆酸(GCA),甘氨鹅去氧胆酸(GCDCA),甘氨脱氧胆酸(GDCA),甘氨石胆酸(GLCA),牛磺熊去氧胆酸(TUDCA),GUDCA,GHDCA,熊去氧胆酸(UDCA),牛磺石胆酸(TLCA)的含量占比降低,TCDCA,HDCA,CA,CDCA,脱氧胆酸(DCA)的占比增加;血清中GHDCA,石胆酸(LCA)含量显著下降(P<0.01),牛磺猪去氧胆酸(THDCA),牛磺胆酸(TCA),GCA,TCDCA,UDCA,CA,CDCA,DCA含量明显增加(P<0.05,P<0.01),CA/DCA显著升高(P<0.01),且CA与CDCA含量占比分别上升19.60%和4.63%;与空白组比较,400 mg·kg-1栀子苷组盲肠内容物中所有的胆汁酸含量均下降,其中GCA,UDCA,HDCA,GCDCA,GDCA,TLCA,GLCA,CDCA,DCA,LCA含量明显下降(P<0.05,P<0.01)。Real-time PCR结果显示,与空白组比较,400 mg·kg-1栀子苷组肝组织中CYP7A1,CYP27A1 mRNA表达明显增加(P<0.05,P<0.01)。结论 400 mg·kg-1栀子苷灌胃,可导致大鼠明显的肝损伤,其肝脏、血清与粪便中胆汁酸发生显著改变,且同一种胆汁酸在肝脏、血清与粪便中的变化不尽相同。然而,由栀子苷所导致的肝损伤与体内胆汁酸变化间的因果关系尚不清楚,仍有待后续进一步研究给予阐明。  相似文献   
3.
目的探讨粪便高迁移率族蛋白B1(HMGB1)、自诱导分子-2(AI-2)和人β-防御素2(HBD2)在新生儿坏死性小肠结肠炎(NEC)中的临床意义及其与肠道菌群的关系。方法选取2017年9月至2019年9月重庆市大渡口区人民医院收治的105例NEC患儿作为NEC组,以及同期出生的50例健康新生儿作为对照组。依据改良Bell-NEC分期标准将NEC患儿分为轻度NEC组及重度NEC组,根据病程分为急性期和恢复期,根据肠道菌群紊乱程度分为Ⅰ度失调组、Ⅱ度失调组及Ⅲ度失调组。检测受试新生儿粪便HMGB1、AI-2和HBD2水平,比较对照组和不同严重程度、不同NEC时期、不同肠道菌群紊乱程度的NEC患儿HMGB1、AI-2和HBD2水平。采用Spearman相关分析HMGB1、AI-2、HBD2水平与急性期NEC病情严重程度、肠道菌群紊乱程度的相关性。结果轻度NEC组和重度NEC组粪便HMGB1水平均高于对照组,且重度NEC组高于轻度NEC组(P<0.05);轻度NEC组和重度NEC组粪便AI-2和HBD2水平均低于对照组,且重度NEC组低于轻NEC度组(P<0.05)。粪便HMGB1水平与NEC病情严重程度呈正相关(r=0.412,P<0.05),AI-2和HBD2水平均与NEC病情严重程度均呈负相关(r=-0.405、-0.381,P<0.05)。NEC急性期和恢复期粪便HMGB1水平均高于对照组,且急性期高于恢复期(P<0.05);急性期粪便AI-2水平低于对照组和恢复期,且恢复期高于对照组(P<0.05);急性期和恢复期粪便HBD2水平均低于对照组,且恢复期高于急性期(P<0.05)。对照组粪便HMGB1水平<Ⅰ度失调组<Ⅱ度失调组<Ⅲ度失调组(P<0.05),而对照组粪便AI-2和HBD2水平>Ⅰ度失调组>Ⅱ度失调组>Ⅲ度失调组(P<0.05);粪便HMGB1水平与肠道菌群紊乱程度呈正相关(r=0.368,P<0.05),AI-2和HBD2水平与肠道菌群紊乱程度均呈负相关(r=-0.432、-0.406,P<0.05)。结论粪便中HMGB1、HBD2和AI-2水平与NEC的病情严重程度有关,并可以反映肠道菌群紊乱情况,而HMGB1水平降低、HBD2和AI-2水平升高则预示着病情好转。  相似文献   
4.
目的:考察厚朴醇提物、远志醇提物及二者配伍对大鼠粪便代谢物的影响,分析其潜在的代谢通路,为探索厚朴缓解远志所致胃肠动力障碍的机制提供实验依据。方法:将40只SD雄性大鼠随机分为空白组,厚朴醇提物组(3. 50 g·kg~(-1)),远志醇提物组(1. 75 g·kg~(-1)),配伍组(3. 50 g·kg~(-1)+1. 75 g·kg~(-1)),连续灌胃给药3 d,收集大鼠末次给药24 h内的粪便,采用UPLC-Q-TOF-MS采集粪便代谢物数据,流动相乙腈(A)-0. 1%甲酸水溶液(B)梯度洗脱(0~0. 5 min,3%A;0. 5~12. 5 min,3%~70%A; 12. 5~13 min,70%~90%A; 13~16 min,90%~97%A; 16~17 min,97%~100%A; 17~22 min,100%A; 22~23 min,100%~3%A),电喷雾离子源,正、负离子模式数据采集范围m/z 50~1 200;借助Progenesis QI v2. 0,SIMCA-P 14. 0,SPSS 20. 0,MetaboAnalyst 4. 0等软件进行多元分析,筛选特征代谢标志物并分析其相关代谢通路。结果:共筛选出5-亚胺甲基四氢叶酸,L-3-羟基犬尿氨酸,7,8-二氢蝶酸等17个特征代谢标志物,其相关代谢通路为不饱和脂肪酸的生物合成、亚油酸代谢、维生素B_6代谢、叶酸生物合成等。结论:厚朴缓解远志所致胃肠动力障碍的作用机制可能与嘌呤代谢、叶酸生物合成、色氨酸代谢、初级胆汁酸生物合成有关。  相似文献   
5.
建立柱前衍生化超高效液相色谱-串联四级杆飞行时间质谱(UHPLC-QTOF-MS/MS)定性、定量表征小鼠粪便内中短链脂肪酸的方法,并用于评价其在抗生素处置前后小鼠粪便样品中的变化。动物实验方案获得江苏省中医药研究院动物实验伦理委员会的批准。以3-硝基苯肼为衍生化试剂,对衍生化反应条件、色谱及质谱条件进行优化,建立了粪便中16个中短链脂肪酸的定性、定量方法。所有分析物在各自浓度范围内线性关系良好(R2>0.99),日内、日间精密度RSD均小于10%,重复性RSD小于6%,加样回收率介于80%~120%之间,样品36 h内稳定性RSD小于7%;联合抗生素处置后小鼠粪便内的中短链脂肪酸种类和含量均发生了明显改变。其中,甲酸、乙酸、丙酸、丁酸、异丁酸、戊酸、乳酸等含量明显降低,而庚酸和丁二酸的含量明显增加。该方法准确、可靠,可作为粪便内中短链脂肪酸的表征方法。  相似文献   
6.
目的 分析微滴式数字PCR(droplet digital PCR, ddPCR)和实时荧光定量PCR(quantitative real-time PCR,qPCR)的核酸检测结果,比较两种方法检测各类样本的差异性,为改进新型冠状病毒核酸检测方案提供数据支持。 方法 利用ddPCR和qPCR技术对已经确诊的3例新型冠状病毒肺炎患者发病不同时间的全血、尿液、粪便共22份标本进行新型冠状病毒核酸检测。 结果 两种方法对人保守区域基因扩增结果一致:全血标本信号最强,尿液次之,粪便最少;ddPCR在1份全血,1份尿液,5份粪便中检出ORF-1ab和N基因的阳性微滴,qPCR仅在3份粪便中检出上述基因,漏检的3个标本基因拷贝数平均浓度为128 copies/ml;ddPCR在发病<5、5~15、>15 d的各类标本中都有检出,qPCR检出以中晚期为主;重症病例用ddPCR均可测到阳性微滴,qPCR检测的各类标本均为阴性;轻症病例的各类标本中qPCR只有粪便核酸检测阳性,ddPCR检出率高于qPCR。 结论 ddPCR可以有效克服qPCR 灵敏度不足的难题,是对qPCR 的有益补充,尤其是针对病毒载量比较低的血液、尿液和可疑的粪便或肛拭子标本,适用于早期感染的判断及患者治愈后出院诊断。  相似文献   
7.
The T5-like siphoviruses DT57C and DT571/2, isolated from horse feces, are very closely related to each other, and most of their structural proteins are also nearly identical to T5 phage. Their LTFs (L-shaped tail fibers), however, are composed of two proteins, LtfA and LtfB, instead of the single Ltf of bacteriophage T5. In silico and mutant analysis suggests a possible branched structure of DT57C and DT571/2 LTFs, where the LtfB protein is connected to the phage tail via the LtfA protein and with both proteins carrying receptor recognition domains. Such adhesin arrangement has not been previously recognized in siphoviruses. The LtfA proteins of our phages are found to recognize different host O-antigen types: E. coli O22-like for DT57C phage and E. coli O87 for DT571/2. LtfB proteins are identical in both phages and recognize another host receptor, most probably lipopolysaccharide (LPS) of E. coli O81 type. In these two bacteriophages, LTF function is essential to penetrate the shield of the host’s O-antigens. We also demonstrate that LTF-mediated adsorption becomes superfluous when the non-specific cell protection by O-antigen is missing, allowing the phages to bind directly to their common secondary receptor, the outer membrane protein BtuB. The LTF independent adsorption was also demonstrated on an O22-like host mutant missing O-antigen O-acetylation, thus showing the biological value of this O-antigen modification for cell protection against phages.  相似文献   
8.
目的评估扬州市沿江地区血吸虫病传播的潜在风险,为江滩地区传播阻断后监测体系的构建提供依据。方法在扬州市沿江的广陵、邗江、江都、仪征和开发区5个区(市)开展水体血吸虫感染性、水上流动传染源、江滩保虫宿主和野粪污染情况调查,评估和分析江滩地区血吸虫病传播阻断后的潜在传播因素与风险特征。结果 2015年,在扬州市沿江地区确定15个重点水域,共投放哨鼠1 500只,饲养后总存活率为99.33%;解剖哨鼠1 490只,未查到阳性哨鼠。共检查水上流动人员5 576名,未查到粪检阳性病人;共检查家畜3 566头(只),其中牛171头、羊1 895只、猪1 500头,未查到病畜。2016年1-3月在8块江滩共投放3 200只鼠夹,在6块江滩捕获野鼠62只,野鼠捕获率为1.94%,未发现感染血吸虫的野鼠;在7块江滩检获新鲜野粪35份,其中牛粪11份、羊粪17份、狗粪2份、其他野粪5份,分别占31.43%、48.57%、5.71%和14.29%,对检获的野粪进行检测,未查出阳性野粪。结论扬州市沿江地区血吸虫病传播风险较低,但江滩放养的牛、羊等家畜粪便所致污染是疫情发生的重大隐患。  相似文献   
9.
目的了解云南省高原山区血吸虫病流行区居民野外自由放牧和野外大便(野便)行为情况。方法选择鹤庆县西甸、磨光2个行政村作为研究试区。随机抽取30%的6~65岁居民,以询问式问卷调查的形式,调查其野外自由放牧和野便的行为情况,并对调查对象进行血清学检查,了解其血吸虫病感染情况。结果共调查居民412人。居民对家畜饲养回答圈养、自由放牧、不知道和没有回答的人数所占的比例分别为55.34%、4.85%、26.94%和12.86%。居民无放牧行为、每周放牧5次、每周放牧≥5次人数占调查人数的比例分别为75.49%、16.02%和8.50%。居民无野便行为、每周野便5次、每周野便≥5次和没有回答的人数占调查人数的比例分别为68.45%、27.67%、2.91%和0.97%。结论鹤庆县血吸虫病流行区居民野外自由放牧和野便行为较普遍,对当地血吸虫病防治工作影响较大,在今后的防治工作中仍应突出人畜粪便管理和禁牧措施,巩固血吸虫病防治成果,以实现传播阻断目标。  相似文献   
10.
Even with continuous vector control, dengue is still a growing threat to public health in Southeast Asia. Main causes comprise difficulties in identifying productive breeding sites and inappropriate targeted chemical interventions. In this region, rural families keep live birds in backyards and dengue mosquitoes have been reported in containers in the cages. To focus on this particular breeding site, we examined the capacity of bird fecal matter (BFM) from the spotted dove, to support Aedes albopictus larval growth. The impact of BFM larval uptake on some adult fitness traits influencing vectorial capacity was also investigated. In serial bioassays involving a high and low larval density (HD and LD), BFM and larval standard food (LSF) affected differently larval development. At HD, development was longer in the BFM environment. There were no appreciable mortality differences between the two treatments, which resulted in similar pupation and adult emergence successes. BFM treatment produced a better gender balance. There were comparable levels of blood uptake and egg production in BFM and LSF females at LD; that was not the case for the HD one, which resulted in bigger adults. BFM and LSF females displayed equivalent lifespans; in males, this parameter was shorter in those derived from the BFM/LD treatment. Taken together these results suggest that bird defecations successfully support the development of Ae. albopictus. Due to their cryptic aspects, containers used to supply water to encaged birds may not have been targeted by chemical interventions.  相似文献   
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