检索结果-南通市图书馆

Mechanistic research:Selenium regulates virulence factors,reducing adhesion ability and inflammatory damage of Helicobacter pylori

引用

World Journal of Gastroenterology 2024年第1期30卷 91-107页

作者： Chun Qin Gan-Rong Huang Ai-Xing Guan Wen-Ting Zhou Hao Chen Pei-Pei Luo Xian-Ke Luo Yan-Qiang Huang Zan-Song Huang Guangxi Technology Innovation Cooperation Base of Prevention and Control Pathogenic Microbes with Drug Resistance Youjiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Department of Digestive Diseases Affiliated Hospital of Youjiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Key Laboratory of the Prevention and Treatment of Drug Resistant Microbial Infecting Youjiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Department of Pathology Wannan Medical CollegeWuhu 241002Anhui ProvinceChina Department of Gastroenterology Wujin People’s Hospital affiliated to Jiangsu UniversityChangzhou 213004Jiangsu ProvinceChina Department of Gastroenterology Guangzhou Liwan District People's HospitalGuangzhou 510370Guangdong ProvinceChina

BACKGROUND The pathogenicity of Helicobacter pylori is dependent on factors including the environment and the host.Although selenium is closely related to pathogenicity as an environmental factor,the specific correlation between them remains unclear.AIM To investigate how selenium acts on virulence factors and reduces their toxicity.METHODS H.pylori strains were induced by sodium selenite.The expression of cytotoxin-associated protein A(CagA)and vacuolating cytotoxin gene A(VacA)was determined by quantitative PCR and Western blotting.Transcriptomics was used to analyze CagA,CagM,CagE,Cag1,Cag3,and CagT.C57BL/6A mice were infected with the attenuated strains subjected to sodium selenite induction,and H.pylori colonization,inflammatory reactions,and the cell adhesion ability of H.pylori were assessed.RESULTS CagA and VacA expression was upregulated at first and then downregulated in the H.pylori strains after sodium selenite treatment.Their expression was significantly and steadily downregulated after the 5th cycle(10 d).Transcriptome analysis revealed that sodium selenite altered the levels affect H.pylori virulence factors such as CagA,CagM,CagE,Cag1,Cag3,and CagT.Of these factors,CagM and CagE expression was continuously downregulated and further downregulated after 2 h of induction with sodium selenite.Moreover,CagT expression was upregulated before the 3rd cycle(6 d)and significantly downregulated after the 5th cycle.Cag1 and Cag3 expression was upregulated and downregulated,respectively,but no significant change was observed by the 5th cycle.C57BL/6A mice were infected with the attenuated strains subjected to sodium selenite induction.The extent of H.pylori colonization in the stomach increased;however,sodium selenite also induced a mild inflammatory reaction in the gastric mucosa of H.pylori-infected mice,and the cell adhesion ability of H.pylori was significantly weakened.CONCLUSION These results demonstrate that H.pylori displayed virulence attenuation after the 10th d of sodium selenite treatment.Sodium s

关键词： Helicobacter pylori Sodium selenite virulence factors Adherence Inflammation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Role of nickel-regulated small RNA in modulation of Helicobacter pylori virulence factors

引用

World Journal of Clinical Cases 2022年第31期10卷 11283-11291页

作者： Fabrício Freire de Melo Hanna Santos Marques Fabian Fellipe Bueno Lemos Marcel Silva Luz Samuel Luca Rocha Pinheiro Lorena Sousa de Carvalho Cláudio Lima Souza Márcio Vasconcelos Oliveira Institution Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094Brazil Campus Vitória da Conquista Universidade Estadual do Sudoeste da BahiaVitória da Conquista 45083-900Brazil

Helicobacter pylori(H.pylori)is a Gram-negative bacterium that infects about half of the world's population.H.pylori infection prevails by several mechanisms of adaptation of the bacteria and by its virulence factors including the cytotoxin associated antigen A(CagA).CagA is an oncoprotein that is the protagonist of gastric carcinogenesis associated with prolonged H.pylori infection.In this sense,small regulatory RNAs(sRNAs)are important macromolecules capable of inhibiting and activating gene expression.This function allows sRNAs to act in adjusting to unstable environmental conditions and in responding to cellular stresses in bacterial infections.Recent discoveries have shown that nickelregulated small RNA(NikS)is a post-transcriptional regulator of virulence properties of H.pylori,including the oncoprotein CagA.Notably,high concentrations of nickel cause the reduction of NikS expression and consequently this increases the levels of CagA.In addition,NikS expression appears to be lower in clinical isolates from patients with gastric cancer when compared to patients without.With that in mind,this minireview approaches,in an accessible way,the most important and current aspects about the role of NikS in the control of virulence factors of H.pylori and the potential clinical repercussions of this modulation.

关键词： Helicobacter pylori Small regulatory RNAs Nickel-regulated small RNA virulence factors Cytotoxin associated antigen A Gastric cancer

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Epilithic biofilm as a reservoir for functional virulence factors in wastewater-dominant rivers after WWTP upgrade

引用

Journal of Environmental Sciences 2021年第3期33卷 27-35页

作者： Guannan Mao Jinsong Liang Qiaojuan Wang Chen Zhao Yaohui Bai Ruiping Liu Huijuan Liu Jiuhui Qu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Harbin Institute of Technology School of Civil and Environmental EngineeringShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China

virulence factors(VFs)confer upon pathogens the ability to cause various types of damage or diseases.Wastewater treatment plants(WWTPs)are important point sources for the emission of pathogens and VFs into receiving rivers.Conventional WWTP upgrades are often implemented to improve the water quality of receiving ecosystems.However,knowledge on the pathogens,VFs,and health risks to receiving aquatic ecosystems after upgrade remains limited.In this study,we investigated detailed pathogenic information,including taxa,pathogenicity,and health risk,in two wastewater-dominant rivers after WWTP upgrade.Using 16S rRNA gene sequencing,we screened 14 potential pathogens in water and epilithic biofilm samples,though they were significantly more enriched in the biofilms.Combining 16S rRNA and metagenomic sequencing data,we identified Pseudomonas and Aeromonas as the dominant pathogenic taxa carrying functional VFs(e.g.,mobility and offensive)in the epilithic biofilm.Moreover,strong pathogen-specific VF-host co-occurrence events were observed in the epilithic biofilm samples,indicating the importance of biofilms as reservoirs and vehicles for VFs.Further,we demonstrated that mobility VF is crucial for biofilm formation and pathogens in biofilm carrying offensive VF may be highly invasive.Quantification and health risk assessment suggested that the skin contact risk of P.aeruginosa carrying VFs was higher than the acceptable probability of 10^(-4)in both water and epilithic biofilm samples,which may threaten ecological and human health.

关键词： Wastewater treatment plant upgrade Epilithic biofilm Pathogens virulence factors Health risk

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characterization of virulence factors in Enteroaggregative and Atypical Enteropathogenic Escherichia coli Strains Isolated from Children with Diarrhea

引用

Advances in Infectious Diseases 2012年第4期2卷 135-142页

作者： Thiago Azevedo Feitosa Ferro Francyelle Costa Moraes Andreia Meneses da Silva Claude Porcy Leandro Amorim Soares Cristina Andrade Monteiro Nyla Thyara Melo Lobao Francisco Amazonas Assis de Mello Valério Monteiro-Neto Patrícia de Maria Silva Figueiredo Research Group of Endemic and Parasitic Diseases CEUMA UniversitySao LuisBrazil Federal Institute of Maranhao Sao LuisBrazil Health and Biological Sciences Center Federal University of MaranhaoSao LuísBrazil

Enteroaggregative (EAEC) and atypical enteropathogenic (EPEC) Escherichia coli are important bacterial etiologic agents causing diarrhea among children. The aim of the present study was to examine the impact of virulence factors predisposes to diarrhea. In this study some virulence properties were examined on 11 EAEC and 8 EPEC strains identified by Polymerase Chain Reaction (PCR), isolated from stool samples of children were analyzed genotypically and phenoltypically for the prevalence of virulence factors. The most frequently detected factor was resistance to serum (94%), followed by curli fimbriae (78%), biofilm production (73%), and gene coding for Extended-Spectrum Beta-Lactamase (ESBL) (68%). EPEC isolates showed at least three of the evaluated properties, while EAEC isolates showed at least two. The prevalence of these virulence factors between the two strains showed no statistical difference. This study showed the heterogeneity of the virulence profile of the isolates of EAEC and atypical EPEC strains and suggests that this diversity may influence in the disease severity.

关键词： E.coli Diarrhea virulence factors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Impact of Helicobacter pylori virulence markers on clinical outcomes in adult populations

引用

World Journal of Gastroenterology 2023年第1期29卷 190-199页

作者： Halim Roshrosh Hanan Rohana Maya Azrad Tamar Leshem Segula Masaphy Avi Peretz Applied Mycology and Microbiology MigalKiryat Shemona 1101202Israel Department of Microbiology Padeh Poriya Medical CenterTiberias 111508Israel

BACKGROUND In recent years,associations between specific virulence markers of Helicobacter pylori(H.pylori)and gastrointestinal disorders have been suggested.AIM To investigate the presence of virulence factors including vacuolating cytotoxin A genotypes(s1m1,s1m2,s2m1,and s2m2),cytotoxin-associated gene A(CagA),and urease activity in H.pylori strains isolated from Arab and Jewish populations in northern Israel and to assess associations between these factors and patients’demographics and clinical outcomes.METHODS Patients(n=108)who underwent gastroscopy at the Baruch Padeh Medical Center,Poriya due to symptomatic gastroduodenal pathologies as part of H.pylori diagnosis were enrolled in the study.Gastric biopsy specimens were collected from the antrum of the stomach.Clinical condition was assessed by clinical pathology tests.Bacteria were isolated on modified BD Helicobacter Agar(BD Diagnostics,Sparks,MD,United States).Bacterial DNA was extracted,and PCR was performed to detect CagA and vacuolating cytotoxin A genes.Urease activity was assessed using a rapid urease test.RESULTS A significant correlation was found between disease severity and patient ethnicity(P=0.002).A significant correlation was found between CagA presence and the s1m1 genotype(P=0.02),which is considered the most virulent genotype.Further,a higher level of urease activity was associated with isolates originating from the Jewish population.Moreover,higher urease activity levels were measured among CagA-/s1m1 and CagA-/s2m2 isolates.CONCLUSION Our study highlights the importance of incorporating molecular methods for detection of virulence markers of H.pylori in order to tailor optimal treatments for each patient.Further investigation should be performed regarding associations between H.pylori virulence factors and ethnicity.

关键词： Helicobacter pylori virulence factors Vacuolating cytotoxin A Cytotoxin-associated gene A Urease activity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Small molecules for combating multidrug-resistant superbug Candida auris infections

引用

Acta Pharmaceutica Sinica B 2022年第11期12卷 4056-4074页

作者： Jie Tu Na Liu Yahui Huang Wanzhen Yang Chunquan Sheng School of Pharmacy Second Military Medical UniversityShanghai 200433China

Candida auris is emerging as a major global threat to human health. C. auris infections are associated with high mortality due to intrinsic multi-drug resistance. Currently, therapeutic options for the treatment of C. auris infections are rather limited. We aim to provide a comprehensive review of current strategies, drug candidates, and lead compounds in the discovery and development of novel therapeutic agents against C. auris. The drug resistance profiles and mechanisms are briefly summarized. The structures and activities of clinical candidates, drug combinations, antifungal chemosensitizers, repositioned drugs, new targets, and new types of compounds will be illustrated in detail, and perspectives for guiding future research will be provided. We hope that this review will be helpful to prompting the drug development process to combat this fungal pathogen.

关键词： Candidaauris Antifungal agents Drug resistance virulence factors Antifungal targets

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Food Safety Risks and Contributing factors of Cronobacter spp.

引用

Engineering 2022年第5期8卷 128-138页

作者： Na Ling Xiuting Jiang Stephen Forsythe Danfeng Zhang Yizhong Shen Yu Ding Juan Wang Jumei Zhang Qingping Wu Yingwang Ye School of Food and Biological Engineering Hefei University of TechnologyHefei 230009China Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application State Key Laboratory of Applied Microbiology Southern ChinaGuangdong Institute of MicrobiologyGuangdong Academy of SciencesGuangzhou 510070China *** Keyworth NG125GYUK

Cronobacter species are a group of Gram-negative opportunistic pathogens,which cause meningitis,sep-ticemia,and necrotizing enterocolitis in neonates and infants,with neurological sequelae in severe cases.Interest in Cronobacter has increased significantly in recent years due to its high virulence in children.In this review,we summarize the current understanding of the prevalence of Cronobacter species in several important food types.We discuss the response mechanisms enabling persistence in adverse growth con-ditions,as well as its pathogenicity.We emphasize the food safety concerns caused by Cronobacter and subsequent control methods and clinical treatments.

关键词： Cronobacter Food contamination Pathogenesis virulence factors Stress response

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Corchorus olitorius aqueous extract attenuates quorum sensing-regulated virulence factor production and biofilm formation

引用

Asian Pacific Journal of Tropical Biomedicine 2021年第2期11卷 66-73页

作者： Hanan M.Al-Yousef Perwez Alam Zakia Khanam Musarat Amina Wafaa H.B.Hassan Department of Pharmacognosy College of PharmacyKing Saud UniversityRiyadhSaudi Arabia University Malaysia Kelantan Campus Jeli17600KelantanMalaysia Department of Pharmacognosy Faculty of PharmacyZagazig University44519 ZagazigEgypt

Objective:To investigate the effect of Corchorus olitorius aqueous fraction(COAF)on quorum sensing(QS)-regulated virulence factors and biofilm formation in Pseudomonas aeruginosa(PAO1).Methods:The preliminary screening of the anti-QS effect of COAF was performed by evaluating the anti-pathogenic activity against Chromobacterium violaceum CV026 biosensor strain.Next,the inhibitory effects of COAF on QS-regulated pyocyanin production,proteolytic and elastolytic activities,swarming motility,and biofilm formation were evaluated in PAO1.Results:The results showed that the treatment of COAF significantly decreased the biofilm biomass,attenuated virulence factors,and inhibited swarming motility of PAO1 without affecting the growth of the bacteria in a dose-dependent manner.COAF at 2000μg/mL significantly decreased Las B elastase activity in PAO1 culture,exopolysaccharide production,swarming motility,pyocyanin level,and biomass of PAO1 by 55%(P<0.05),60%(P<0.01),61%(P<0.01),65%(P<0.01)and 73%(P<0.01),respectively.In addition,the production of violacein was decreased by 62%(P<0.01)with the treatment of a high dose of COAF.Conclusions:These findings indicate that COAF can be a potential source of anti-QS agents.

关键词： Corchorus olitorius L Anti-quorum sensing activity Pseudomonas aeruginosa Chromobacterium violaceum virulence factors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Comparative study of gut microbiota from captive and confiscatedrescued wild pangolins

引用

Journal of Genetics and Genomics 2021年第9期48卷 825-835页

作者： Chunbing Liu Jingyang Hu Yajiang Wu David M.Irwin Wu Chen Zhigang Zhang Li Yu State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan School of Life SciencesYunnan UniversityKunming 650091China Guangzhou Zoo&Guangzhou Wildlife Research Center Guangzhou 510070China Department of Laboratory Medicine and Pathobiology University of TorontoTorontoOntario M5S 1A8Canada

Pangolins are among the most critically endangered animals due to widespread poaching and worldwide trafficking. Captive breeding is considered to be one way to protect them and increase the sizes of their populations. However, comparative studies of captive and wild pangolins in the context of gut microbiota are rare. Here, the gut microbiome of captive and confiscated-rescued wild pangolins is compared, and the effects of different periods of captivity and captivity with and without antibiotic treatment are considered.We show that different diets and periods of captivity, as well as the application of antibiotic therapy, can alter gut community composition and abundance in pangolins. Compared to wild pangolins, captive pangolins have an increased capacity for chitin and cellulose/hemicellulose degradation, fatty acid metabolism, and short-chain fatty acid synthesis, but a reduced ability to metabolize exogenous substances. In addition to increasing the ability of the gut microbiota to metabolize nutrients in captivity, captive breeding imposes some risks for survival by resulting in a greater abundance of antibiotic resistance genes and virulence factors in captive pangolins than in wild pangolins. Our study is important for the development of guidelines for pangolin conservation, including health assessment, disease prevention, and rehabilitation of wild pangolin populations.

关键词： Pangolin Gut microbiome Captivity Antibiotic resistance genes virulence factors

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Clinical significance of Helicobacter pylori cagA and iceA genotype status

引用

World Journal of Gastroenterology 2010年第35期16卷 4443-4447页

作者： Nasser Amjad Hussain Ali Osman Najibah Abdul Razak Junaini Kassian Jeffri Din Nasuruddin bin Abdullah Department of Surgery International Islamic University Malaysia Department of Basic Medical Sciences International Islamic University MalaysiaKuantan 25710PahangMalaysia Department of Surgery Hospital Tengku Ampuan Afzan

AIM:To study the presence of Helicobacter pylori(H.pylori) virulence factors and clinical outcome in H.pylori infected patients.METHODS:A prospective analysis of ninety nine H.pylori-positive patients who underwent endoscopy in our Endoscopy suite were included in this study.DNA was isolated from antral biopsy samples and the presence of cagA,iceA,and iceA2 genotypes were determined by polymerase chain reaction and a reverse hybridization technique.Screening for H.pylori infection was performed in all patients using the rapid urease test(CLO-Test).RESULTS:From a total of 326 patients who underwent endoscopy for upper gastrointestinal symptoms,99 patients were determined to be H.pylori-positive.Peptic ulceration was seen in 33 patients(33%).The main virulence strain observed in this cohort was the cagA gene isolated in 43 patients.cagA was associated with peptic ulcer pathology in 39.5%(17/43) and in 28%(16/56) of non-ulcer patients.IceA1 was present in 29 patients(29%) and iceA2 in 15 patients(15%).Ulcer pathology was seen in 39%(11/29) of patients with iceA1,while 31%(22/70) had normal findings.The corresponding values for iceA2 were 33%(5/15) and 33%(28/84),respectively.CONCLUSION:virulence factors were not common in our cohort.The incidence of factors cagA,iceA1 and iceA2 were very low although variations were noted in different ethnic groups.

关键词： Ethnicity Helicobacter pylori Peptic ulcer disease virulence factors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：