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Effects of dietary supplementation of probiotic,Clostridium butyricum,on growth performance,immune response,intestinal barrier function,and digestive enzyme activity in broiler chickens challenged with Escherichia coli K88 被引量:45
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作者 Ling Zhang Lingling Zhang +5 位作者 Xiu'an Zhan Xinfu Zeng Lin Zhou Guangtian Cao An'guo Chen Caimei Yang 《Journal of Animal Science and Biotechnology》 CAS CSCD 2016年第1期107-115,共9页
Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varyin... Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum (C. butyficum) on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli (E. coil) K88. Methods: The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment (NC) consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment (PC) consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment (CB) consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment (CS) consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results: The body weight (BW) and average day gain (ADG) in the broilers of CB group were higher (P 〈 0.05) than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher (P 〈 0.05) concentration of tumor necrosis factor-a (TNF-a) at 3 and 7 d post-challenge, and higher (P 〈 0.05) concentration of interleukin-4 (IL-4) at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower (P 〈 0.05) at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower (P 〈 0.05) at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher (P 〈 0.05) jejunum villi height than those in PC, NC, or CS treatment at 展开更多
关键词 Broiler chickens Clostridium butyricum Digestive enzyme activity escherichia coli K88 Growth performance Immune response Intestinal barrier
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A study of the efficacy of bacterial biofilm cleanout for gastrointestinal endoscopes 被引量:28
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作者 Fang, Ying Shen, Zhe +6 位作者 Li, Lan Cao, Yong Gu, Li-Ying Gu, Qing Zhong, Xiao-Qi Yu, Chao-Hui Li, You-Ming 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第8期1019-1024,共6页
AIM:To compare the influence and clearance effect of enzymatic and non-enzymatic detergents against Escherichia coli (E. coli) biofilm on the inner surface of gastroscopes.METHODS:Teflon tubes were incubated in a mixt... AIM:To compare the influence and clearance effect of enzymatic and non-enzymatic detergents against Escherichia coli (E. coli) biofilm on the inner surface of gastroscopes.METHODS:Teflon tubes were incubated in a mixture of different detergents and E. coli culture (106 CFU/mL) for 72 h at 15℃,and biofilms on the inner surface of the teflon tubes were analyzed by bacterial count and scanning electron microscopy. To evaluate the clear-ance effect of detergents,after biofilms were formed on the inner surface of Teflon tubes by 72 h lavage with E. coli culture,tubes were lavaged by enzymatic and non-enzymatic detergents at a speed of 250 mL/min,then biofilms on the inner surface were analyzed by bacterial count and scanning electron microscopy.RESULTS:Non-enzymatic detergent had a better inhi-bition function on biofilm formation than enzymatic de-tergent as it reduced bacterial burden by 2.4 log compared with the control samples (P = 0.00). Inhibition function of enzymatic detergent was not significantly different to that of control samples and reduced bac-terial burden by 0.2 log on average (P > 0.05). After lavaging at 250 mL/min for 3 min,no living bacteria were left in the tubes. Scanning electron microscopy observation showed biofi lms became very loose by the high shear force effect. CONCLUSION:Non-enzymatic detergent has a better inhibition effect on biofilm formation at room temperature. High speed pre-lavage and detergents are very important in temporal formed biofilm elimination. 展开更多
关键词 ENDOSCOPY escherichia coli biofi lm Scanning electron microscopy Bacterial count
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新CMY型头孢菌素酶在大肠埃希菌中的流行 被引量:22
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作者 管希周 刘又宁 +4 位作者 罗燕萍 佘丹阳 周光 陈良安 徐雅萍 《中华医学杂志》 CAS CSCD 北大核心 2004年第22期1872-1875,共4页
目的 对临床产质粒介导AmpC酶大肠埃希菌的耐药表型以及分子生物学特性进行研究 ,以期发现新的头孢菌素酶。方法 对从临床分离的大肠埃希氏菌先后用纸片扩散法、三维试验、等电聚焦试验以及微量稀释法等进行表型检测。然后用接合试验... 目的 对临床产质粒介导AmpC酶大肠埃希菌的耐药表型以及分子生物学特性进行研究 ,以期发现新的头孢菌素酶。方法 对从临床分离的大肠埃希氏菌先后用纸片扩散法、三维试验、等电聚焦试验以及微量稀释法等进行表型检测。然后用接合试验、多重PCR以及基因测序等方法进行分子生物学研究。结果  719株受试的大肠埃希菌经三维试验 ,等电聚焦以及酶抑制试验表明有 6株细菌都能够产一种等电点 (PI)为 8 9的能够被氯唑西林抑制而不能被克拉维酸抑制的 β 内酰胺酶。用微量稀释法检测表明这些菌株对多种三代头孢菌素耐药 ,但对头孢吡肟、亚胺培南和美洛培南均敏感。接合试验表明它们携带的AmpC酶具有转移性 ,多重PCR检测表明这些基因来源于费氏枸橼酸杆菌家族 ,DNA测序表明该基因和CMY 2以及CMY 7有 99%的同源性 ,为一种新的CMY型头孢菌素酶。结论 发现了一种新的CMY型头孢菌素酶 ,它介导了高产AmpC酶大肠埃希菌对多种抗生素的耐药 。 展开更多
关键词 头孢菌素酶 大肠埃希菌 AMPC酶 微量稀释法 三维试验 耐药 等电聚焦 高产 抑制试验 水平传播
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Expression in Escherichia coli of Three Different Soybean Late Embryogenesis Abundant (LEA) Genes to Investigate Enhanced Stress Tolerance 被引量:23
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作者 YingLAN DanCAI Yi-ZhiZHENG 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2005年第5期613-621,共9页
Abstract: In order to identify the function of late embryogenesis abundant (LEA) genes, in vitro functional analyses were performed using an Escherichia coli heterologous expression system. Three soybean late embryoge... Abstract: In order to identify the function of late embryogenesis abundant (LEA) genes, in vitro functional analyses were performed using an Escherichia coli heterologous expression system. Three soybean late embryogenesis abundant (LEA) genes, PM11 (GenBank accession No. AF004805; group 1), PM30 (AF117884; group 3), and ZLDE-2 (AY351918; group 2), were cloned and expressed in a pET-28a system. The gene products were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by mass spectrometry. E. coli cells containing the recombinant plasmids or empty vector as controls were treated by salt and low temperature stress. Compared with control cells, the E. coli cells expressing either PM11 or PM30 showed a shorter lag period and improved growth when transferred to LB (Luria-Bertani) liquid media containing 800 mmol/L NaCl or 700 mmol/L KCl or after 4°C treatment. E. coli cells expressing ZLDE-2 did not show obvious growth improvement both in either high KCl medium or after 4°C treatment. The results indicate that the E. coli expression system is a simple, useful method to identify the functions of some stress-tolerant genes from plants. 展开更多
关键词 escherichia coli gene expression LEA gene osmotic stress salt stress SOYBEAN
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食醋杀灭细菌的性能及效果观察 被引量:22
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作者 张超英 鲁晓晴 滕洪松 《齐鲁医学杂志》 2007年第3期196-198,共3页
目的 了解食醋杀灭细菌的性能及效果。方法 采用悬液定量杀菌试验及现场消毒试验方法,对食醋消毒效果进行观察。结果 不同浓度的食醋溶液作用不同时间对金黄色葡萄球菌、大肠杆菌和白色念珠菌的杀灭效果不同,浓度越大、作用时间越长... 目的 了解食醋杀灭细菌的性能及效果。方法 采用悬液定量杀菌试验及现场消毒试验方法,对食醋消毒效果进行观察。结果 不同浓度的食醋溶液作用不同时间对金黄色葡萄球菌、大肠杆菌和白色念珠菌的杀灭效果不同,浓度越大、作用时间越长杀菌效果越好(F=6.89~156.83,P〈0.05);对手自然菌作用2min,平均杀灭率为0.9915±0.0032;对厨房内台面、砧板、菜刀、碗柜、瓷碗、冰箱保鲜室表面擦拭消毒10min,对自然菌的平均杀灭率在0.9720以上;对室内空气自然菌的杀灭率随熏蒸时间的延长而提高(F=1212.13、5024.46,P〈0.05),当室内有人时,杀灭率有所降低(t=5.08-30.48,P〈0.05);置于54℃恒温箱(相对湿度≥0.75)存放14d,醋酸总含量下降8.372g/L。结论 食醋对金黄色葡萄球菌、大肠杆菌、白色念珠菌和自然菌有极强的杀灭效果,且性能稳定。 展开更多
关键词 食醋 金黄色葡萄球菌 大肠杆菌 白色念珠菌 自然菌 稳定性
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Micro-encapsulated essential oils and organic acids combination improves intestinal barrier function,inflammatory responses and microbiota of weaned piglets challenged with enterotoxigenic Escherichia coli F4(K88^+) 被引量:22
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作者 Yetong Xu Ludovic Lahaye +3 位作者 Zhengxiao He Jinxiao Zhang Chengbo Yang Xiangshu Piao 《Animal Nutrition》 SCIE 2020年第3期269-277,共9页
This study evaluated the effects of micro-encapsulated(protected)organic acids(OA)and essential oils(EO)combination,P(OA+EO),and effects of a regular blend of free acids(FA)on the growth,immune responses,intestinal ba... This study evaluated the effects of micro-encapsulated(protected)organic acids(OA)and essential oils(EO)combination,P(OA+EO),and effects of a regular blend of free acids(FA)on the growth,immune responses,intestinal barrier and microbiota of weaned piglets challenged with enterotoxigenic Escherichia coli(ETEC)F4(K88^+).A total of 30 crossbred(Duroc×Landrace×Large White)weaned barrows(7.41±0.06 kg,28 d old)were assigned randomly to 5 treatments:1)non-challenged positive control(PC),2)ETEC F4(K88^+)-challenged negative control(NC),3)NC+kitasamycin at 50 mg/kg+olaquindox at 100 mg/kg+free acidifier(FA)at 5 g/kg,4)NC+kitasamycin at 50 mg/kg+olaquindox at 100 mg/kg+P(OA+EO)at 1 g/kg(P1),5)NC+kitasamycin at 50 mg/kg+olaquindox at 100 mg/kg+P(OA+EO)at 2 g/kg(P2).Each dietary treatment had 6 replicates of one piglet each and the study lasted for 3 wk.On d 7,pigs in NC,FA,P1 and P2 were orally dosed with 10 mL of ETEC F4(K88^+)culture(1×10^9 CFU/mL).From d 7 to 14 after the ETEC F4(K88^+)challenge,P1 increased gain-to-feed ratio(G:F)significantly(P<0.05)compared with NC and FA groups.From d 14 to 21,P2 increased the average daily gain of pigs(P<0.05)compared with NC and FA groups.Compared with NC,P2 reduced tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and IL-10 concentrations(P<0.05)in sera collected at 4 h later after ETEC F4(K88^+)challenge.On d 21,P1 increased occludin and zonula occludens-1 protein expression in ileum compared with NC(P<0.05).After this 3-wk experiment,alpha diversity of gut microbiota was decreased by P2 compared with PC,and P1 increased the relative abundance of Lactobacillus in ileum,cecum and colon(P<0.05).In co nclusio n,dietary P(OA+EO)additive at 2 g/kg combined with antibiotics could improve piglet performance and attenuate inflammation,and P(OA+EO)additive at 1 g/kg combined with antibiotics improved intestinal barrier and increased beneficial microbiota composition after an F4(K88^+)challenge. 展开更多
关键词 Essential oil Organic acid Enterotoxigenic escherichia coli F4(K88^+) Gut health Weaned piglet
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Immunogenicity noninferiority study of 2 doses and 3 doses of an Escherichia coli-produced HPV bivalent vaccine in girls vs.3 doses in young women 被引量:20
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作者 Yue-Mei Hu Meng Guo +20 位作者 Chang-Gui Li Kai Chu Wen-Gang He Jing Zhang Jian-Xiang Gu Juan Li Hui Zhao Xiang-Hong Wu Bi-Zhen Lin Zhi-Jie Lin Xing-Mei Yao Ya-Fei Li Fei-Xue Wei Yue Huang Ying-Ying Su Feng-Cai Zhu Shou-Jie Huang Hui-Rong Pan Ting Wu Jun Zhang Ning-Shao Xia 《Science China(Life Sciences)》 SCIE CAS CSCD 2020年第4期582-591,共10页
A new HPV-16/18 bivalent vaccine expressed by the Escherichia coli has been proven to be efficacious in adult women.A randomized,immunogenicity noninferiority study of this candidate vaccine was conducted in December ... A new HPV-16/18 bivalent vaccine expressed by the Escherichia coli has been proven to be efficacious in adult women.A randomized,immunogenicity noninferiority study of this candidate vaccine was conducted in December 2015 in China.Girls aged 9–14 years were randomized to receive 2 doses at months 0 and 6(n=301)or 3 doses at months 0,1 and 6(n=304).Girls aged 15–17 years(n=149)and women aged 18–26 years(n=225)received 3 doses.The objectives included noninferiority analysis of the IgG geometric mean concentration(GMC)ratio(95%CI,lower bound>0.5)to HPV-16 and HPV-18 at month 7 in girls compared with women.In the per-protocol set,the GMC ratio of IgG was noninferior for girls aged 9–17 years receiving 3 doses compared with women(1.76(95%CI,1.56,1.99)for HPV-16 and 1.93(95%CI,1.69,2.21)for HPV-18)and noninferior for girls aged 9–14 years receiving 2 doses compared with women(1.45(95%CI,1.25,1.62)for HPV-16 and 1.17(95%CI,1.02,1.33)for HPV-18).Noninferiority was also demonstrated for neutralizing antibodies.The immunogenicity of the HPV vaccine in girls receiving 3 or 2 doses was noninferior compared with that in young adult women. 展开更多
关键词 immunobridging NONINFERIORITY human PAPILLOMAVIRUS vaccine escherichia COLI GIRLS
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Sterilization Effects of Bacterial Inhibitor on Escherichia coli in Cattle Manure Compost 被引量:20
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作者 敖日格乐 王纯洁 +4 位作者 于俊娥 斯木吉德 吴美云 程佳 陈昆 《Agricultural Science & Technology》 CAS 2008年第6期154-156,共3页
[Objective] The aim of this study was to explore the sterilization effects on Escherichia coli by adding bacterial inhibitor(CaCN2)during the process of cattle manure composting so as to provide a theoretical basis fo... [Objective] The aim of this study was to explore the sterilization effects on Escherichia coli by adding bacterial inhibitor(CaCN2)during the process of cattle manure composting so as to provide a theoretical basis for cattle manure harmless treatment.[Method] Both experimental groups supplemented with 2.0% bacterial inhibitor and control groups without bacterial inhibitor were cultured under different temperatures(20,30,37,50,60 ℃)to determine the optimal composing temperature.Under 30 ℃,different bacterial inhibitor doses(0,2.0%,2.5%,3.0%)were added into the compost to obtain the optimal bacterial inhibitor addition dose.[Result] 30,50 and 60 ℃ were ideal temperatures for sterilization of E.coli.Under 30 ℃,E.coli couldn't be detected in 2.5% dose group and 3.0% dose group after culture for 48 h,demonstrating no less than 2.5% bacterial inhibitor should be added.[Conclusion] It has an important significance to enhance the sterilization effects on E.coli by adding CaCN2 into cattle manure compost especially in winter. 展开更多
关键词 BACTERIAL INHIBITOR Cattle MANURE COMPOSTING escherichia coli
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A型流感病毒对小鼠肺部菌群及趋化因子CCL5和CXCL10的影响及麻杏石甘汤干预作用研究 被引量:21
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作者 王平 赵澄 +5 位作者 卢芳国 吴涛 张香港 魏科 李玲 田维毅 《中草药》 CAS CSCD 北大核心 2020年第21期5523-5537,共15页
目的探索麻杏石甘汤(Maxing Shigan Decoction,MSD)通过影响小鼠肺部菌群及趋化因子CCL5和CXCL10表达而防治流感病毒感染的潜在机制。方法通过鼻腔接种法建立A型流感病毒感染小鼠模型,经ig给药或生理盐水3、7 d后,计算肺指数和肺指数抑... 目的探索麻杏石甘汤(Maxing Shigan Decoction,MSD)通过影响小鼠肺部菌群及趋化因子CCL5和CXCL10表达而防治流感病毒感染的潜在机制。方法通过鼻腔接种法建立A型流感病毒感染小鼠模型,经ig给药或生理盐水3、7 d后,计算肺指数和肺指数抑制率,HE染色检测肺组织病理变化,应用免疫组化、酶联免疫吸附试验(ELISA)、实时荧光定量PCR(RT-PCR)法检测肺组织中CCL5和CXCL10蛋白和mRNA表达变化,并取小鼠肺组织进行16S rRNA基因V3~V4可变区测序、物种注释及聚类,分析Alpha多样性和Beta多样性及组间差异物种,分析CCL5、CXCL10表达与肺部菌群变化的关系。结果给药3 d后,模型组肺指数明显高于对照组(P<0.01)和药物组(P<0.05、0.01),肺部炎性细胞浸润明显。麻杏石甘汤组肺部炎性细胞浸润明显减轻,肺指数抑制率与奥司他韦组相似,肺损伤的组织学定量评价指标(IQA)值较模型组明显降低(P<0.01)。模型组CCL5和CXCL10表达明显高于对照组(P<0.01),奥司他韦组和麻杏石甘汤组CCL5和CXCL10表达明显低于模型组(P<0.05、0.01)。16S rRNA基因测序结果显示,模型组拟杆菌属、埃希菌属、变形杆菌属相对丰度增加,粪球菌属相对丰度降低。奥司他韦和麻杏石甘汤能显著降低拟杆菌属、埃希菌属、变形杆菌属相对丰度,增加粪球菌属相对丰度;Alpha多样性分析结果显示各组ACE指数、Chao1指数、Shannon指数比较P>0.05,组间丰富度和多样性无差异。Beta多样性分析结果显示,给药3 d后,组间样品点无交集,组间肺菌群构成有差异。各组间有显著性差异物种。Spearman相关性分析显示,CCL5和CXCL10表达与埃希菌属、变形杆菌属、拟杆菌属丰度呈正相关,与粪球菌属丰度呈负相关。给药7 d后,各组间肺部菌群结构组成及CCL5、CXCL10表达无显著差异。结论麻杏石甘汤可能通过促进肺部有益菌生长改善肺部微生态环境及免疫微环境,对流感病毒 展开更多
关键词 A型流感病毒 麻杏石甘汤 肺部菌群 趋化因子 CCL5 CXCL10 鼻腔接种法 Alpha多样性 Beta多样性 拟杆菌属 埃希菌属 变形杆菌属 粪球菌属 ACE指数 Chao1指数 Shannon指数 Spearman相关性分析
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Escherichia coli in chronic inflammatory bowel diseases: An update on adherent invasive Escherichia coli pathogenicity 被引量:19
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作者 Margarita Martinez-Medina Librado Jesus Garcia-Gil 《World Journal of Gastrointestinal Pathophysiology》 CAS 2014年第3期213-227,共15页
Escherichia coli(E. coli), and particularly the adherent invasive E. coli(AIEC) pathotype, has been increasingly implicated in the ethiopathogenesis of Crohn's disease(CD). E. coli strains with similar pathogenic ... Escherichia coli(E. coli), and particularly the adherent invasive E. coli(AIEC) pathotype, has been increasingly implicated in the ethiopathogenesis of Crohn's disease(CD). E. coli strains with similar pathogenic features to AIEC have been associated with other intestinal disorders such as ulcerative colitis, colorectal cancer, and coeliac disease, but AIEC prevalence in these diseases remains largely unexplored. Since AIEC was described one decade ago, substantial progress has been made in deciphering its mechanisms of pathogenicity. However, the molecular bases that characterize the phenotypic properties of this pathotype are still not well resolved. A review of studies focused on E. coli populations in inflammatory bowel disease(IBD) is presented here and we discuss about the putative role of this species on each IBD subtype. Given the relevance of AIEC in CD pathogenesis, we present the latest research findings concerning AIEC host-microbe interactions and pathogenicity. We also review the existing data regarding the prevalence and abundance of AIEC in CD and its association with other intestinal diseases from humans and animals, in order to discuss the AIEC disease- and hostspecificity. Finally, we highlight the fact that dietarycomponents frequently found in industrialized countries may enhance AIEC colonization in the gut, which merits further investigation and the implementation of preventative measures. 展开更多
关键词 Adherent INVASIVE escherichia coli Inflammatory BOWEL DISEASE Crohn’s DISEASE Pathogenesis Epidemiology
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Role and mechanisms of action of escherichia coli nissle 1917 in the maintenance of remission in ulcerative colitis patients: an update 被引量:19
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作者 Franco Scaldaferri Viviana Gerardi +8 位作者 Francesca Mangiola Loris Riccardo Lopetuso Marco Pizzoferrato Valentina Petito Alfredo Papa Jovana Stojanovic Andrea Poscia Giovanni Cammarota Antonio Gasbarrini 《World Journal of Gastroenterology》 SCIE CAS 2016年第24期5505-5511,共7页
Ulcerative colitis (UC) is a chronic inflammatory disease, whose etiology is still unclear. Its pathogenesis involves an interaction between genetic factors, immune response and the &#x0201c;forgotten organ&#x... Ulcerative colitis (UC) is a chronic inflammatory disease, whose etiology is still unclear. Its pathogenesis involves an interaction between genetic factors, immune response and the &#x0201c;forgotten organ&#x0201d;, Gut Microbiota. Several studies have been conducted to assess the role of antibiotics and probiotics as additional or alternative therapies for Ulcerative Colitis. Escherichia coli Nissle (EcN) is a nonpathogenic Gram-negative strain isolated in 1917 by Alfred Nissle and it is the active component of microbial drug Mutaflor<sup>&#x000ae;</sup> (Ardeypharm GmbH, Herdecke, Germany and EcN, Cadigroup, In Italy) used in many gastrointestinal disorder including diarrhea, uncomplicated diverticular disease and UC. It is the only probiotic recommended in ECCO guidelines as effective alternative to mesalazine in maintenance of remission in UC patients. In this review we propose an update on the role of EcN 1917 in maintenance of remission in UC patients, including data about efficacy and safety. Further studies may be helpful for this subject to further the full use of potential of EcN. 展开更多
关键词 Ulcerative colitis escherichia coli Nissle Metanalysis Probiotic Randomized trial Inflammatory bowel disease
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Cu Ions Dissolution from Cu-bearing Antibacterial Stainless Steel 被引量:18
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作者 Li Nan and Ke Yang Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2010年第10期941-944,共4页
This work addressed the antibacterial mechanism of copper ions dissolved from the Cu-bearing antibacterial stainless steel in the bacterial solution by electrochemical measurements and X-ray photoelectron spectroscopy... This work addressed the antibacterial mechanism of copper ions dissolved from the Cu-bearing antibacterial stainless steel in the bacterial solution by electrochemical measurements and X-ray photoelectron spectroscopy (XPS).Experimental results showed that the antibacterial rate reached over 99.9% only when the reaction time between the antibacterial stainless steel and Escherichia coli (E.coli) lasted for 9 h,and the antibacterial stainless steel was more susceptible to the corrosion in the bacterial solution,which was attributed to more copper ions dissolved from surface of the steel contacted with the bacteria,a crucial reason leading to death of the bacteria. 展开更多
关键词 Antibacterial stainless steel Copper ions CORROSION escherichia coli (E.coli)
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食品中Escherichia coli O157:H7微滴数字PCR绝对定量检测方法的建立 被引量:15
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作者 魏咏新 马丹 +5 位作者 李丹 徐蕾蕊 魏海燕 张西萌 刘莉 曾静 《食品科学》 EI CAS CSCD 北大核心 2020年第16期259-265,共7页
为建立食品中Escherichia coli O157:H7的微滴数字聚合酶链式反应(droplet digital polymerase chain reaction,ddPCR)快速定量检测方法,针对E.coli O157:H7的特异性单拷贝基因hlyA设计引物探针,并进行特异性、灵敏度和重复性实验,同时... 为建立食品中Escherichia coli O157:H7的微滴数字聚合酶链式反应(droplet digital polymerase chain reaction,ddPCR)快速定量检测方法,针对E.coli O157:H7的特异性单拷贝基因hlyA设计引物探针,并进行特异性、灵敏度和重复性实验,同时通过人工污染三文鱼样品的检测,比较平板计数法、real-time PCR和ddPCR方法的测定值效果。结果表明,所建立的E.coli O157:H7 ddPCR检测方法具有良好的特异性、灵敏性和重复性。细菌纯培养液中定量限为105 CFU/mL,检出限为25 CFU/mL,人工污染三文鱼样品中检出限为110 CFU/g。对不同人工污染水平的三文鱼样品,ddPCR与平板计数的测定值结果无显著性差异(P>0.05),比real-time PCR方法的测定值结果更加稳定、准确。因此,本研究建立的ddPCR方法能够更加快速、准确、灵敏、特异地绝对定量检测食品中E.coli O157:H7。 展开更多
关键词 escherichia coli O157:H7 微滴数字聚合酶链式反应 实时聚合酶链式反应 定量限 检出限
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Role of bacteria in the etiopathogenesis of inflammatory bowel disease 被引量:15
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作者 Nicolas Barnich Arlette Darfeuille-Michaud 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第42期5571-5576,共6页
Increased numbers of mucosa-associated Escherichia coli are observed in both of the major inflammatory bowel diseases,Crohn's disease(CD)and ulcerative colitis(UC).A potential pathophysiological link between the p... Increased numbers of mucosa-associated Escherichia coli are observed in both of the major inflammatory bowel diseases,Crohn's disease(CD)and ulcerative colitis(UC).A potential pathophysiological link between the presence of pathogenic invasive bacteria and genetic host susceptibility of patients with ileal CD is suspected.In CD patients,with increased ileal expression of the CEACAM6 molecule acting as a receptor recognized by type 1 pilus bacterial adhesin,and with the identification of mutations in the NOD2-encoding gene,the presence of pathogenic invasive bacteria could be the link between abnormal ileal bacterial colonization and innate immune responses to invasive bacteria.In a susceptible host,the sequential etiological steps of the disease induced by adherent-invasive E.coli(AIEC)are:(1)abnormal colonization via binding to the CEACAM6 receptor,which is overexpressed in the ileal mucosa of CD patients;(2)ability to adhere to and to invade intestinal epithelial cells,which allows bacteria to cross the mucosal barrier;(3)survival and replication within infected macrophages in the lamina propria;and(4)induction of tumor necrosis factor-α secretion and granuloma formation. 展开更多
关键词 Adherent-invasive escherichia coli Crohn's disease Inflammatory bowel disease Ulcerative colitis
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CTX-M-14, CTX-M-24 and resistance in Escherichia coli and Klebsiella pneumoniae clinical isolates 被引量:13
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作者 XIONG Zi-zhong ZHU De-mei WANG Fu ZHANG Ying-yuan 《Chinese Medical Journal》 SCIE CAS CSCD 2006年第2期160-164,共5页
Extended-spectrum β-lactamases (ESBLs) are the main cause of resistance to the third and forth-generation cephalosporins in Enterobacteriaceae, which are mediated by plasmids and can hydrolyze oxyiminoaminothiazoly... Extended-spectrum β-lactamases (ESBLs) are the main cause of resistance to the third and forth-generation cephalosporins in Enterobacteriaceae, which are mediated by plasmids and can hydrolyze oxyiminoaminothiazolyl cephalosporins and monobactams. Most of ESBLs are mutants of the classical TEM and SHV types, with one or more amino-acid substitution(s) in the active site. 展开更多
关键词 extended-spectrum β-lactamases CTX-M-14 CTX-M-24 escherichia coli Klebsiella pneumoniae
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Understanding the multifunctionality in Cu-doped BiVO_4 semiconductor photocatalyst 被引量:13
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作者 Chhabilal Regmi Yuwaraj K.Kshetri +3 位作者 Ramesh Prasad PANDey Tae-Ho Kim Gobinda Gyawali Soo Wohn Lee 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第1期84-97,共14页
A visible light-induced, Cu-doped BiVO_4 photocatalyst was synthesized by a microwave hydrothermal method. The photocatalytic efficiency was investigated in the degradation of model water pollutants like Methylene Blu... A visible light-induced, Cu-doped BiVO_4 photocatalyst was synthesized by a microwave hydrothermal method. The photocatalytic efficiency was investigated in the degradation of model water pollutants like Methylene Blue(dye) and ibuprofen(pharmaceuticals), as well as the inactivation of Escherichia coli(bacteria). The Cu-doped BiVO4 samples showed better efficiency than undoped BiVO_4, and the 1 wt.% Cu-doped BiVO_4 sample showed the best efficiency. The degradation of Methylene Blue reached 95%, while the degradation of ibuprofen reached 75%, and the inactivation of E. coli reached 85% in irradiation with visible light. The appearance of additional absorption band shoulders and widening of the optical absorption in the visible range makes the prepared powder an efficient visible light-driven photocatalyst. Moreover, the formation of an in-gap energy state just above the valance band as determined by density functional theory(DFT) first principle calculation, facilitates the wider optical absorption range of the doped system. Similarly, this in-gap energy state also acts as an electron trap, which is favorable for the efficient separation and photoexcited charge carriers' transfer process. The formation of oxygen vacancies due to doping also improved the separation of the charge carrier, which promoted the trapping of electrons and inhibited electron hole recombination, thus increasing the photocatalytic activity. No decrease in the efficiency of the 1 wt.% Cu-doped BiVO_4 photocatalyst in the degradation of ibuprofen over three consecutive cycles revealed the stability of the photocatalyst towards photocorrosion. These findings highlight the multifunctional applications of Cu-doped BiVO_4 in wastewater containing multiple pollutants. 展开更多
关键词 BIVO4 PHOTOCATALYST METHYLENE Blue IBUPROFEN escherichia COLI First principle calculation
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Macleaya cordata extract alleviated oxidative stress and altered innate immune response in mice challenged with enterotoxigenic Escherichia coli 被引量:13
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作者 Guiping Guan Sujuan Ding +3 位作者 Yulong Yin Veeramuthu Duraipandiyan Naif Abdullah Al-Dhabi Gang Liu 《Science China(Life Sciences)》 SCIE CAS CSCD 2019年第8期1019-1027,共9页
This study examines the effects of dietary Macleaya cordata extract(MCE) on bacterial burden and resistance to enterotoxigenic Escherichia coli(ETEC) in ICR mice. ICR mice were randomly distributed into one of the fol... This study examines the effects of dietary Macleaya cordata extract(MCE) on bacterial burden and resistance to enterotoxigenic Escherichia coli(ETEC) in ICR mice. ICR mice were randomly distributed into one of the following groups:(i) basal diet;(ii)basal diet with 200 mg kg–1 MCE;(iii) basal diet challenged with ETEC;and(iv) basal diet with 200 mg kg–1 MCE and challenged with ETEC. Following a 7-day period of pre-treatment, CTRL-ETEC and MCE-ETEC mice were subjected to oral infection using 5×108 E. coli SEC 470. The results showed dietary 200 mg kg–1 MCE markedly reduced intestinal ETEC burden(P<0.05) and the disease-associated mortality was significantly alleviated in the MCE treated group(P<0.05). In addition,dietary MCE markedly alleviated ETEC-induced oxidative stress, evidenced by the lowered methane dicarboxylic aldehyde(MDA) abundance and enhanced activities of catalase and glutathione peroxidase(P<0.05). Furthermore, MCE mice exhibited higher immune activity, which might have further mediated ETEC infection. These results indicate MCE plays a preventative role with respect to ETEC infection. Future research should aim to develop MCE as a therapeutic approach to the promotion of intestinal health and a safeguard against ETEC infection. 展开更多
关键词 Macleaya cordata EXTRACT enterotoxigenic escherichia COLI bacterial BURDEN OXIDATIVE stress
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大肠杆菌HB101感受态的热化学研究 被引量:13
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作者 谢志雄 陈向东 +2 位作者 沈萍 刘义 屈松生 《化学学报》 SCIE CAS CSCD 北大核心 2000年第2期153-156,共4页
利用LKB-2277生物活性检测系统,测定了在生理盐水中,采用氯化钙法建立大肠杆菌感受态过程中的代谢热输出.生理盐水中大肠杆菌及其感受态进行内源代谢的热化学方程满足:P=Kc+Adc/dP_0=K’c^0氯化钙处理后,K与P_0均增大,说明内源代谢活性... 利用LKB-2277生物活性检测系统,测定了在生理盐水中,采用氯化钙法建立大肠杆菌感受态过程中的代谢热输出.生理盐水中大肠杆菌及其感受态进行内源代谢的热化学方程满足:P=Kc+Adc/dP_0=K’c^0氯化钙处理后,K与P_0均增大,说明内源代谢活性增强,这与大肠杆菌感受态建立过程中一系列生理生化活性的调整是一致的,表明大肠杆菌感受态的建立很可能有其内在的调节机制,而不完全是人工诱导的. 展开更多
关键词 大肠杆菌 感受态 热化学 HB101 生理生化活性
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肠杆菌科细菌KPC型碳青霉烯酶的研究 被引量:14
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作者 谢宁 郭斌 +2 位作者 蔡燕 黄义山 廖涛 《中国感染控制杂志》 CAS 2012年第4期266-269,共4页
目的了解某院临床分离的肠杆菌科细菌产KPC型碳青霉烯酶情况及其基因型别。方法收集该院2009—2010年临床分离的肠杆菌科细菌1 801株,经药敏试验筛选出耐药性高的菌株,采用改良Hodge试验和聚合酶链反应(PCR)扩增检测细菌产KPC型碳青霉... 目的了解某院临床分离的肠杆菌科细菌产KPC型碳青霉烯酶情况及其基因型别。方法收集该院2009—2010年临床分离的肠杆菌科细菌1 801株,经药敏试验筛选出耐药性高的菌株,采用改良Hodge试验和聚合酶链反应(PCR)扩增检测细菌产KPC型碳青霉烯酶情况,并测序分析其基因型别。结果 1 801株肠杆菌科细菌中,有783株(43.48%)对第三代头孢菌素耐药,其中4株还对碳青霉烯类抗菌药物耐药;改良Hodge试验初筛出2株耐药菌株,经PCR扩增证实为碳青霉烯酶blaKPC-2基因。结论该院已出现产KPC-2型碳青霉烯酶耐药基因的肠杆菌科细菌,临床与实验室应加强监测和控制。 展开更多
关键词 肠杆菌科 KPC酶 碳青霉烯酶 阴沟肠杆菌 肺炎克雷伯菌 大肠埃希菌 抗药性 微生物
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Colon cancer-associated B2 Escherichia coli colonize gut mucosa and promote cell proliferation 被引量:12
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作者 Jennifer Raisch Emmanuel Buc +9 位作者 Mathilde Bonnet Pierre Sauvanet Emilie Vazeille Amélie de Vallée Pierre Déchelotte Claude Darcha Denis Pezet Richard Bonnet Marie-Agnès Bringer Arlette Darfeuille-Michaud 《World Journal of Gastroenterology》 SCIE CAS 2014年第21期6560-6572,共13页
AIM: To provide further insight into the characterization of mucosa-associated Escherichia coli (E. coli) isolated from the colonic mucosa of cancer patients.
关键词 B2 escherichia coli Carcinoembryonic antigen-related cell adhesion molecule 6 Cell proliferation Colon cancer Polyketide synthase genomic island
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