酪酸梭菌与婴儿型双歧杆菌对产气荚膜梭菌试管内生物拮抗作用的研究

用酪酸权菌（Clostridium butyricum）和婴儿型双歧杆菌（Bifidobacterium Infantis）对产气荚膜梭菌（Clostriduim perfringens）进行试管内的生物拮抗试验。将酪酸梭菌、婴儿型双歧杆菌及酪酸梭菌和婴儿型双歧杆菌分别对产气荚膜酸菌以一定的比例等量混合接种于GAM液体培养基中进行厌氧培养。实验证明酪酸梭菌和婴儿型双歧能明显抑制产气荚膜梭菌的生长,并且比各自单独培养时显示了较强的生物拮抗作用。     

酪酸梭菌和婴儿型双歧杆菌对霍乱弧菌的拮抗试验

了解酪酸梭菌和婴儿型双歧杆菌单独及混合培养时对霍乱弧菌的拮抗作用。将酪酸梭菌ＬＣＬ１６６和婴儿型双歧杆菌ＬＣＬ１７２分别与霍乱弧菌Ｏ１、Ｏ１３９单独和混合培养,定时对霍乱弧菌计数,并对菌数的对数进行在检验。两株菌混合培养时对霍乱弧菌的抑制效果基本相同,单独和混合培养时对霍乱弧菌的拮抗作用主要由酪酸梭菌引起,酪酸梭菌具有抑制霍乱弧菌的作用。     

酪酸梭菌与双歧杆菌对肠道致病菌的体外生物拮抗作用

目的：探讨酪酸梭菌和婴儿型双歧杆菌对某些肠道致病菌的拮抗作用,方法：将酪酸梭菌和婴和型双歧杆菌单株菌及两株菌混合后分别与几株肠道致病菌混合接种于GAM液体培养其中进行厌氧培养,通过平板菌落计数法计算肠道致病菌的菌数,结果：经混合培养后肠道致病菌的菌数明显下降,结论：酪酸梭菌LCL166株和婴儿型双歧杆菌LCL172株在体外能明显抑制几株肠道致病菌的生长繁殖。     

酪酸梭菌-婴儿型双歧杆菌二联活菌制剂的研究

对酪酸梭菌－婴儿型双歧杆菌二联活菌制剂的特性及功效进行研究和分析。方法：通过实验鼠进行刺激生长试验、活菌数测定、毒理试验、调节肠道菌群试验、免疫调节作用来观察制剂的作用。结果：小鼠肠道中双歧杆菌、乳杆菌、酪酸梭菌数量明显增加,高剂量能增加小鼠抗体生成细胞数。     

酪酸梭菌--婴儿型双歧杆菌二联活菌制剂对人体肠道菌群的调节试验

目的　观察酪酸梭菌——婴儿型双歧杆菌二联活菌制剂对受试人群肠道菌群的影响。方法　检测受试者服用前后的肠道菌群并计数。结果　肠杆菌、肠球菌、拟杆菌的数量无明显变化 ,双歧杆菌、乳杆菌的数量明显增加 ,差异有非常显著性 (P<0 .0 1) ,结论　酪酸梭菌——婴儿型双歧杆菌二联活菌制剂具有一定的调节人体肠道菌群、增殖双歧杆菌和乳杆菌的作用。     

酪酸梭菌二联活菌制剂治疗儿科不同类型腹泻的疗效观察

目的评估酪酸梭菌、婴儿型双歧杆菌二联活菌制剂治疗儿科最常见3种不同类型腹泻的疗效。方法选择2008年至2010年3年间合肥市第一人民医院儿科有腹泻症状的住院患者224例,采用随机数表法分为酪酸梭菌、婴儿型双歧杆菌二联活菌制剂治疗组110例,未加用或用加其他微生态制剂的对照组114例。2组的性别、年龄、病情相比较,差异无统计学意义(P>0.05)。结果酪酸梭菌、婴儿型双歧杆菌二联活菌制剂治疗组总有效率为95.5%,对照组为80.7%,差异有统计学意义(P<0.01)。2组治疗后的平均止泻时间为(2±1.45)d和(3.9±1.11)d,差异有统计学意义(P<0.05)。结论酪酸梭菌、婴儿型双歧杆菌二联活菌制剂治疗婴幼儿腹泻优于未加用或加用其他微生态制剂,且未见明显不良反应。     

酷酸梭菌——婴儿型双歧杆菌二联活菌制剂对人体肠道菌群的调节试验

目的 观察酷酸梭菌－－婴儿型双歧杆菌二联活菌制剂对受试人群肠道菌群的影响。方法 检测受试者服用前后的肠道菌群并计数。结果 肠杆菌、肠球菌、拟杆菌的数量无明显变化,双歧杆菌、乳杆菌的数量明显增加,差异有非常显著性（Ｐ〈０．０１）,结论 酪酸梭菌－－婴儿型双歧杆菌二联活菌制剂具有一定的调节人体肠道菌群、增殖双歧杆菌和乳杆菌的作用。     

酪酸梭菌的研究与应用进展

酪酸梭菌属于微生态制剂,酪酸梭菌具有抑制肠出血性大肠埃希菌、痢疾志贺菌、霍乱沙门菌、霍乱弧菌等肠道致病菌的生长繁殖,抑制艰难梭菌生长繁殖,促进双歧杆菌、乳酸菌等肠道有益菌的生长繁殖,加强肠道黏膜膜营养代谢、保护受损的黏膜屏障,激活免疫细胞、改善并恢复肠道正常免疫力,防治肿瘤的生长的作用.所以酪酸梭菌制剂对腹泻、肠炎、肠易激综合征、结直肠癌新生儿黄疸等疾病都有很强的防治作用.     

酪酸梭菌对艰难梭菌感染的防治研究

目的:观察酪酸梭菌对艰难梭菌感染的防治效果.方法:用艰难梭菌产毒株人工感染BALB/C小鼠,感染前后分别用酪酸梭菌进行预防与治疗,并检测盲肠内容物细胞毒性和进行肠黏膜病理观察.结果:酪酸梭菌不能预防艰难梭菌的感染,但在艰难梭菌感染后则能明显降低艰难梭菌的产毒力和盲肠黏膜的病理损伤.结论:酪酸梭菌对小鼠艰难梭菌感染有明显的治疗作用.     

酪酸梭菌-双歧杆菌二联活菌制剂对慢性腹泻患者肠道菌群的影响

给慢性腹泻病人口服酪酸梭菌-双歧杆菌二联活菌制剂,然后检测患者服药前后的肠道菌群变化.患者服用药品后,葡萄球菌、酵母菌、消化球菌、真杆菌和小梭菌的数量无明显变化,肠杆菌、肠球菌的数量明显减少,拟杆菌、双歧杆菌、乳杆菌的数量明显增加,其中肠球菌、肠杆菌、拟杆菌和双歧杆菌的变化有显著性(P﹤0.05),提示酪酸梭菌-双歧杆菌二联活菌制剂对慢性腹泻病人的肠道菌群具有明显的影响、具有增殖拟杆菌、双歧杆菌和乳杆菌的作用.     

艰难梭菌荚膜致病作用的初步研究

本文在我室先前研究的基础上,以3株艰难梭菌的荚膜多糖提取物、全菌悬液以及全菌免疫血清分别在小鼠中进行半数致死量和保护试验等动物实验,以探讨艰难梭菌荚膜的致病作用。结果测得其中一株艰难梭菌的荚膜多糖对小鼠有致死毒性,其LD50为2.83mg,特异性抗血清保护试验证实艰难梭菌免疫血清对动物有保护作用。实验结果可能为进一步研究艰难梭菌荚膜的致病作用提供了参考资料。     

Inhibition of adhesion of Clostridium difficile to Caco-2 cells

Abstract For many microorganisms, including Clostridium difficile , mucosal association is an important factor influencing intestinal colonisation and subsequent infection. Inhibition of adhesion of C. difficile to intestinal mucosa could be a new promising strategy for prevention and treatment of antibiotic-associated diarrhoea. We investigated the possibilities of influencing the adhesion of C. difficile by xylitol and bovine colostrum.whey. Caco-2 cells and C. difficile cells were incubated with 1%, 5% and 10% solutions of xylitol and colostrum. Our study revealed that both xylitol and colostrum inhibited the adhesion of C. difficile to Caco-2 cells. Inhibition by xylitol was dose-dependent. When compared to the control, the count of adherent C. difficile decreased 3.4 times when treated with 1% xylitol, 12 times when 5% xylitol was applied, and 18.7 times when treated with 10% xylitol. The inhibition of adherence by colostrum was partially dose-dependent: 3.1 times in the case of 1%, and 5.5 times in the cases of 5% and 10% colostrum. Further experimental and clinical studies are needed for the application of xylitol and colostrum in the treatment and prophylaxis of pseudomembraneous colitis.     

神经毒素原性酪酸梭菌与E型肉毒梭菌毒素的精制及特性比较

对首次自Ｅ型肉毒中毒食品中分离到的一株神经毒素原性酪酸梭菌（ＬＣＬ１５５）所产生的神经毒素,同Ｅ型肉毒梭菌（Ｅ１５３）所产生的神经毒素进行了精制及特性比较,发现（１）两菌神经毒素的分子量,Ｎａｔｉｖｅ－ＰＡＧＥ测试均为３２０ｋＤａ;ＳＤＳ－ＰＡＧＥ测试则均为１４７ｋＤａ,非毒性非血凝素部分均为１２８ｋＤａ;用胰蛋白酶激活神经毒素后发现两菌神经毒素均由分子量为１０３ｋＤａ的Ｈ链和４８ｋＤａ的Ｌ链组成。（２）两菌神经毒素柱层析图像基本一致,但在菌体毒素提取效果及精制效果诸方面,分离的酪酸梭菌却都较差。（３）胰蛋白酶激活试验表明：两菌神经毒素达到最大毒力所需激活时间不等。在相同温度下,分离的酪酸梭菌毒素只需５ｍｉｎ,而Ｅ型肉毒梭菌毒素却需３０ｍｉｎ,提示两菌神经毒素激活动力学上存在差异。（４）琼脂双扩散试验结果表明两菌神经毒素的抗原性是一致的,没有发现沉淀线呈交叉或部分交叉现象。     

Toxigenic C. difficile induced inflammatory marker expression by human intestinal epithelial cells is asymmetrical

Clostridium difficile infection of the intestinal epithelium and consequent pseudomembranous colitis is an important cause of morbidity and mortality. Pathogenesis has been ascribed exclusively to toxin production. Using in vitro models of human intestinal epithelial layers, we show that exposure to toxigenic C. difficile upregulates epithelial expression of IL-8 and ICAM-1, two molecules important in neutrophil chemoattraction and adhesion and subsequent inflammation. IL-8 production was also stimulated by toxin-containing supernatants. C difficile induced IL-8 release was inhibited by specific antiserum. Increased ICAM-1 expression only occurred after basolateral exposure to C. difficile while apical exposure had no effect on ICAM-1 expression. However, transepithelial electrical resistance was impaired by apical exposure to bacterial suspensions. We suggest that apical exposure to C. difficile induces changes in epithelial layer integrity which allows the bacteria and/or the toxin access to the basolateral compartment where pathogenic inflammatory mechanisms are activated.     

Variation in nuclear DNA content in an ex-type isolate of Penicillium measured by continuous flow microfluorimetry

Abstract The effect of purified enterotoxin produced by Clostridium difficile on Chinese hamster ovary (CHO) cells was examined. In a certain concentration range (0.9–3.6 μ g/ml), purified toxin caused CHO elongation, namely a cytotonic effect, which is similar to a typical morphological change in CHO cells induced by cholera enterotoxin. At a higher concentration, purified enterotoxin had a cytotoxic effect on CHO cells which was neutralized by anti- C. difficile enterotoxin, but not by anti- C. difficile cytotoxin. Thus, enterotoxin had both cytotonic and cytotoxic effects on CHO cells. About 60 and 180 min were required for binding of enterotoxin to CHO cells, and its internalization, respectively, both times being much longer than those for C. difficile cytotoxin.     

兰州市婴幼儿艰难梭菌带菌状况

在兰州市随机采集的２１６名健康婴幼儿粪标本经分离并对其培养特性、菌落菌体形态特征、生化反应特性以及毒素原性等进行一系列检查,检出了３７人的粪便含有艰难梭菌（１０４─１０８／ｇ）,检出总阳性率为１７．１％,新生儿、婴儿及幼儿各年龄组的检出阳性率分别为１３．５％（１９／４１）、３３．３％（１３／３９）、１３．９％（５／３６）。３７株分离菌中毒素原性阳性者仅有８株（２１．６％）,均分布于婴儿与幼儿两组。新生儿１４１人中２７人的粪标本为胎粪,只有１人（３．７％）含艰难梭菌（２×１０６／ｇ）,但不产毒素。所有婴幼儿中有２２人因各种原因曾用过抗菌药物,但仅有２人的粪便含艰难梭菌,而且均为非产毒株,表明艰难梭菌检出率与药物服用之间似无显著的相关性。