粪便分离大肠埃希菌CRISPR系统在耐药及毒力中的作用

目的探索粪便分离大肠埃希菌成簇规律间隔短回文重复序列(clustered regularly interspaced short palindromic repeats, CRISPR)在耐药及毒力中的作用。方法收集某院2018年8-12月分离自慢性腹泻患者及健康体检者粪便样本的大肠埃希菌。采用纸片扩散法检测其药物敏感性,PCR法检测并比较分析腹泻患者及健康体检者粪便样本分离大肠埃希菌的系统发育群、耐药基因及CRISPR系统。结果共收集到142株大肠埃希菌,源于63例慢性腹泻患者(疾病组)和79例健康体检者(健康组)。药敏结果显示,氨苄西林耐药率为48.0%,其余抗菌药物敏感率为73.1%～100.0%。63株源于慢性腹泻患者粪便样本分离大肠埃希菌中CRISPR系统的检出率显著低于79株源于健康体检者(3.2%vs 46.8%,χ~2=33.538,P0.001)。在被检测的耐药基因中,63株疾病组中11株阳性(7株bla_(CTX-M-1)组、3株bla_(CTX-M-9)组和1株mcr-1),79株健康组中4株bla_(CTX-M-1)组,未携带耐药基因菌株中CRISPR系统的检出率显著高于携带耐药基因菌株(0.0%vs 29.9%,P=0.011)。43株高毒力菌株(B2群和D群)中CRISPR系统的检出率显著高于99株低毒力菌株(A群和B1群)(44.2%vs 20.2%,χ~2=8.656,P=0.003)。结论粪便分离大肠埃希菌对常用抗菌药物仍保持较高敏感性。CRISPR系统可能在粪便分离大肠埃希菌毒力及耐药基因的传播方面发挥重要作用。     

Intestinal lactoflora in Estonian and Norwegian patients with antibiotic associated diarrhea

The disruption of intestinal microbiota is an important risk factor for the development of Clostridium difficile caused antibiotic associated diarrhea (AAD). The role of intestinal lactoflora in protection against C. difficile is unclear. Fecal samples (n = 74) from AAD patients were investigated for C. difficile and lactobacilli by culture and real-time PCR. Lactobacilli were identified by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) and sequencing of 16S rRNA. In C. difficile negative cases we found somewhat higher counts of intestinal Lactobacilli (5.02 vs. 2.15 CFU log₁₀/g; p = 0.053) by culture and more frequently Lactobacillus plantarum (33.3% vs. 9.4%; p = 0.03) as compared with positive ones. Results of total counts of lactobacilli comparing Estonian and Norwegian samples were conflicting by culture and PCR. We found higher colonization of Norwegian AAD patients with L. plantarum (21% vs. 5%, p = 0.053) and Estonians with Lactobacillus gasseri (19% vs. 2%, p = 0.023). Particular lactobacilli (e.g. L. plantarum) may have a role in protection against C. difficile, whereas the meaning of total counts of lactobacilli remains questionable. In different persons and nations, different lactobacilli species may have a protective role against C. difficile.     

2010年夏季急性细菌感染性腹泻患儿沙门菌感染分析

本文旨在了解急性细菌感染性腹泻患儿中沙门菌的感染现状及其耐药性.采集2010年7月1日~2010年9月30日复旦大学附属儿科医院门诊及住院急性细菌感染性腹泻患儿的粪便标本,进行沙门菌分离、培养及鉴定,采用Kirby-Bauer法进行药敏试验.共收集急性细菌感染性腹泻患儿粪便标本 1 045份,检出沙门菌 160株,阳性...     

Circannual Incidence of Giardia Lamblia

A circannual rhythm of Giardia lamblia positive stools was found by examination of records from three clinical laboratories in central Arkansas for the period 1980-1986. Cosinor analysis of monthly Giardia incidence based on stool specimen records from approximately 12,000 patients over the 7-year period revealed a circannual rhythm (P< 0.001) on the basis of percent positive patients/month, with a computive acrophase occurring in late summer and minimum values in the winter. Patients involved in the study were primarily from the central Arkansas metropolitan areas, southern delta regions and northern mountainous regions of the state. Analysis of the data on the basis of total positive Giardia patients/month also revealed a circannual rhythm with the acrophase again occurring in late summer. The overall mean for percent positive stool specimens for the 7-year period was 5.3%, compared with the national average of 3.8% for G. lamblia positive stools. The data indicate that there may be a “Giardia season” in Arkansas since they could not be explained on the basis of day-care age distribution, or geographic origin. Awareness by epidemiologists, public health officials and other health care professionals of this circannual incidence of giardiasis is important for the prevention, diagnosis and treatment of this infectious disorder.     

抗生素相关性腹泻患儿肠道菌群变化与血清细胞因子的关系

目的研究抗生素相关性腹泻(AAD)患儿肠道菌群变化与血清细胞因子的相关性及其临床意义。方法选择2018年5月至2019年5月在我院儿科住院且使用过抗生素治疗的儿童,根据是否发生AAD分为AAD组和非AAD组。另取同期进行体检的健康儿童作为对照组。检测各组对象粪便中双歧杆菌、乳杆菌、肠球菌和肠杆菌的数量,血清中肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)的含量,并采用Logistics回归分析AAD的相关因素。结果 AAD组儿童粪便中双歧杆菌、乳杆菌的数量低于非AAD组及对照组,而粪便中肠球菌、肠杆菌的数量及血清中TNF-α、IL-6的水平高于非AAD组及对照组(均P0.05)。Logistics回归分析显示,抗生素使用时间≥5 d、联用抗生素、TNF-α及IL-6增多、双歧杆菌及乳杆菌减少是AAD发生的独立危险因素(均P0.05)。结论肠道菌群紊乱与AAD的发病有关并且能够增加患者炎症因子的释放,其中益生菌的减少是AAD发生的主要独立危险因素。     

双歧三联活菌胶囊对结肠癌术后化疗相关性腹泻的疗效

目的探讨双歧三联活菌胶囊对结肠癌术后化疗相关性腹泻患者的疗效,为该病的治疗提供参考。方法选择2017年5月至2019年5月在本院接受治疗的90例结肠癌术后化疗相关性腹泻患者为研究对象,回顾性分析其治疗方案并分为对照组(48例,接受常规治疗)和研究组(42例,接受双歧三联活菌胶囊联合常规治疗)。两组患者持续治疗1周后对比其治疗效果,肠黏膜屏障功能指标[二胺氧化酶(DAO)、D乳酸(DLA)、内毒素(Endotoxin)],营养相关指标[血红蛋白(Hb)、白蛋白(ALB)、转铁蛋白(TRF)、前白蛋白(PA)]水平和药物相关不良反应发生情况的差异。结果治疗1周后,研究组患者治疗总有效率(100.00%)大于对照组(89.58%)患者,同时其疗效分级差异也有统计学意义(均P<0.05)。研究组患者血清中DAO、DLA、Endotoxin的水平低于对照组,而Hb、ALB、TRF、PA的水平高于对照组(均P<0.05)。治疗期间,两组患者均未发生明显药物相关不良反应。结论双歧三联活菌胶囊辅助治疗可有效增加结肠癌术后化疗相关性腹泻的治疗效果,安全性良好。     

痛泻要方对肝气乘脾泄泻小鼠肠道微生物的影响

目的探讨痛泻要方对肝气乘脾泄泻小鼠肠道微生物的影响,为肝气乘脾泄泻及中医经典药方治疗泄泻的机制提供实验依据。方法SPF级昆明小鼠随机分为正常组10只和模型组15只,造模成功后,取正常组和模型组各5只,将剩余模型组小鼠随机分为自然恢复组和痛泻要方干预组各5只,痛泻要方干预组灌胃痛泻要方治疗3 d,分别在造模成功和治疗后取肠道内容物进行微生物培养,然后记录内容物中各种菌的数量。结果造模后,模型组小鼠细菌总数、大肠埃希菌、双歧杆菌、乳杆菌的数量均有上升趋势,与正常组相比只有细菌总数[(23.9±3.51)vs(1.35±0.30),10⁸ CFU/g]差异有统计学意义(t=-11.061,P=0.008)。治疗后,痛泻要方干预组小鼠恢复了肝气乘脾泄泻引起的肠道微生物失衡,其中与自然恢复组相比痛泻要方治疗对大肠埃希菌的影响最明显[(1.63±1.19)vs(8.47±0.84),10⁶ CFU/g;t=8.124,P=0.001],细菌总数、双歧杆菌、乳杆菌数量均受影响,但差异无统计学意义(P>0.05)。肝气乘脾造模组小鼠的肠道微生物定植抗力(B/E值)降低,而痛泻要方干预组的趋近于正常组。结论肝气乘脾泄泻小鼠肠道细菌总数、大肠埃希菌、双歧杆菌、乳杆菌等的数量增加,B/E值降低,痛泻要方干预能够恢复肝气乘脾泄泻引起的肠道微生物失衡,并通过调节肠道微生物以提高B/E值来治疗泄泻。     

猪流行性腹泻病毒单克隆抗体及其抗原表位的研究进展

猪流行性腹泻(Porcine epidemic diarrhea,PED)是由猪流行性腹泻病毒(PED virus,PEDV)引起的一种严重危害养猪生产的常见疫病。近年来,由于新的PEDV变异毒株的出现,许多国家的养猪业遭受了巨大的经济损失。PEDV也因此受到更多关注,关于PEDV的研究报道也日渐增多。基于国内外有关PEDV的最新研究进展,本文系统归纳和分析了PEDV结构蛋白和非结构蛋白单克隆抗体以及单克隆抗体识别的特异性抗原表位,以期为开发鉴别诊断方法和表位疫苗等提供信息。