452 results match your criteria tcdb study

Structural basis for CSPG4 as a receptor for TcdB and a therapeutic target in Clostridioides difficile infection.

Nat Commun 2021 06 18;12(1):3748. Epub 2021 Jun 18.

Department of Physiology and Biophysics, University of California, Irvine, CA, USA.

C. difficile is a major cause of antibiotic-associated gastrointestinal infections. Two C. Read More

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Genomic evolution and virulence association of sequence type 37 (ribotype 017) in China.

Emerg Microbes Infect 2021 Jun 14:1-0. Epub 2021 Jun 14.

School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, 310053, China.

sequence type (ST) 37 (ribotype 017) is one of the most prevalent genotypes circulating in China. However, its genomic evolution and virulence determinants were rarely explored. Whole-genome sequencing, phylogeographic and phylogenetic analyses were conducted for ST37 isolates. Read More

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Genetic diversity and phylogenetic analysis of the surface layer protein A gene (slpA) among Clostridioides difficile clinical isolates from Tehran, Iran.

Anaerobe 2021 Jun 8;70:102403. Epub 2021 Jun 8.

Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Clostridioides difficile is the most common causative agent of healthcare-associated diarrhea. C. difficile strains produce a crystalline surface layer protein (SlpA), encoded by the slpA gene. Read More

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Clostridioides difficile spores stimulate inflammatory cytokine responses and induce cytotoxicity in macrophages.

Anaerobe 2021 May 31;70:102381. Epub 2021 May 31.

Department of Biochemistry and Microbiology, Oklahoma State University Center for Health Sciences, Tulsa, OK, USA; Oklahoma State University College of Osteopathic Medicine at Cherokee Nation, Tahlequah, OK, USA. Electronic address:

Clostridioides difficile is a gram-positive, spore-forming anaerobic bacterium, and the leading cause of antibiotic-associated diarrhea worldwide. During C. difficile infection, spores germinate in the presence of bile acids into vegetative cells that subsequently colonize the large intestine and produce toxins. Read More

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Molecular Detection of Toxigenic among Diarrheic Dogs and Cats: A Mounting Public Health Concern.

Vet Sci 2021 May 22;8(6). Epub 2021 May 22.

Department of Zoonoses, Faculty of Veterinary Medicine, Cairo University, Cairo 12211, Egypt.

Nowadays, pet animals are known to be asymptomatic carriers of . This study was conducted to investigate the burden of toxigenic among diarrheic dogs and cats using direct PCR on fecal samples to reveal better insights about the epidemiology of such toxigenic strains referring to its public health significance. For this purpose, fecal samples were obtained from 58 dogs and 42 cats experiencing diarrhea. Read More

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Frequency of toxin genes and antibiotic resistance pattern of isolates in diarrheal samples among hospitalized patients in Hamadan, Iran.

Gastroenterol Hepatol Bed Bench 2021 ;14(2):165-173

Department of Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.

Aim: This study was designed to investigate the prevalence of , its toxin-producing genes, and antibiotic resistance patterns in diarrheal samples from hospitalized patients in Hamadan, Iran.

Background: Today, concerns over infection (CDI) have significantly increased due to reduced susceptibility to antibiotics used for CDI treatment. Toxins produced by strains are associated with disease severity and outcome. Read More

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January 2021

Molecular Characterization of, and Antimicrobial Resistance in, from Thailand, 2017-2018.

Microb Drug Resist 2021 May 5. Epub 2021 May 5.

School of Biomedical Sciences, The University of Western Australia, Nedlands, Australia.

Antimicrobial resistance (AMR) plays an important role in the pathogenesis and spread of infection (CDI). Many antimicrobials, such as fluoroquinolones, have been associated with outbreaks of CDI globally. This study characterized AMR among clinical strains in Thailand, where antimicrobial use remains inadequately regulated. Read More

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Cwl0971, a novel peptidoglycan hydrolase, plays pleiotropic roles in Clostridioides difficile R20291.

Environ Microbiol 2021 Apr 24. Epub 2021 Apr 24.

Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.

Clostridioides difficile is a Gram-positive, spore-forming, toxin-producing anaerobe that can cause nosocomial antibiotic-associated intestinal disease. Although the production of toxin A (TcdA) and toxin B (TcdB) contribute to the main pathogenesis of C. difficile, the mechanism of TcdA and TcdB release from cell remains unclear. Read More

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The prevalence of Clostridioides difficile on farms, in abattoirs and in retail foods in Ireland.

Food Microbiol 2021 Sep 27;98:103781. Epub 2021 Feb 27.

Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland. Electronic address:

An increasing proportion of Clostridioides difficile infections (CDI) are community acquired. This study tested farm, abattoir and retail food samples for C. difficile, using peer reviewed culture and molecular methods. Read More

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September 2021

Fecal Microbiota Transplantation for Recurrent Clostridioides difficile Infection Associates With Functional Alterations in Circulating microRNAs.

Gastroenterology 2021 Apr 9. Epub 2021 Apr 9.

Department of Biosciences, John van Geest Cancer Research Centre, Centre for Health Aging and Understanding Disease, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom. Electronic address:

Background And Aims: The molecular mechanisms underlying successful fecal microbiota transplantation (FMT) for recurrent Clostridioides difficile infection (rCDI) remain poorly understood. The primary objective of this study was to characterize alterations in microRNAs (miRs) following FMT for rCDI.

Methods: Sera from 2 prospective multicenter randomized controlled trials were analyzed for miRNA levels with the use of the Nanostring nCounter platform and quantitative reverse-transcription (RT) polymerase chain reaction (PCR). Read More

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toxins enhanced the production of CXC chemokine ligand 2 and tumor necrosis factor-α via Toll-like receptors in macrophages.

J Med Microbiol 2021 Apr;70(4)

Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Tokyo 143-8540, Japan.

infection (CDI) causes toxin-mediated enteropathy, such as antibiotic-associated diarrhoea and pseudomembranous colitis. Rho-glucosylating toxin A (TcdA) and toxin B (TcdB) have been clearly implicated in pathogenesis, whereas the virulence of binary toxin (CDT) is still debated. We hypothesized that CDT is involved in the host immune response and plays a pivotal role in establishing virulence by modulating pro-inflammatory cytokine production; this is achieved through the integral Toll-like receptor (TLR) signalling pathways. Read More

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Systematic Evaluation of Parameters Important for Production of Native Toxin A and Toxin B from .

Toxins (Basel) 2021 03 27;13(4). Epub 2021 Mar 27.

Department of Bacteria, Parasites and Fungi, Statens Serum Institut, 2300 Copenhagen, Denmark.

In the attempt to improve the purification yield of native toxin A (TcdA) and toxin B (TcdB) from , we systematically evaluated culture parameters for their influence on toxin production. In this study, we showed that culturing in a tryptone-yeast extract medium buffered in PBS (pH 7.5) that contained 5 mM ZnCl and 10 mM glucose supported the highest TcdB production, measured by the sandwich ELISA. Read More

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The cytotoxic effect of Clostridioides difficile pore-forming toxin CDTb.

Biochim Biophys Acta Biomembr 2021 Jun 6;1863(6):183603. Epub 2021 Mar 6.

Institute of Pharmacology and Toxicology, Ulm University Medical Center, Ulm, Germany.

Clostridioides (C.) difficile is clinically highly relevant and produces several AB-type protein toxins, which are the causative agents for C. difficile-associated diarrhea and pseudomembranous colitis. Read More

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The prognostic value of toxin B and binary toxin in infection.

Gut Microbes 2021 Mar 4:1-8. Epub 2021 Mar 4.

Unit of Infectious Diseases and Clinical Microbiology. Jerez De La Frontera University Hospital, Jerez De La Frontera, Cádiz, Spain.

To study the association between detection of the gene encoding the binary toxin (CDT) and direct detection of toxinB (TcdB) from feces with the appearance of serious disease, complications, or recurrence in a prospective series of cases. A total of 220 confirmed cases were included, using a two-step algorithm: an initial study to detect the enzyme, glutamate dehydrogenase (GDH), followed, in cases of positivity, by detection of the tcdB. tcdB-positive patients were investigated for the presence of CDT and TcdB. Read More

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High Prevalence of Multidrug-Resistant Following Extensive Use of Antimicrobials in Hospitalized Patients in Kenya.

Front Cell Infect Microbiol 2020 8;10:604986. Epub 2021 Feb 8.

US Army Medical Research Directorate-Africa, Nairobi, Kenya.

Introduction: is a neglected pathogen in many African countries as it is generally not regarded as one of the major contributors toward the diarrheal disease burden in the continent. However, several studies have suggested that infection (CDI) may be underreported in many African settings. The aim of this study was to determine the prevalence of CDI in hospitalized patients, evaluate antimicrobial exposure, and detect toxin and antimicrobial resistance profiles of the isolated strains. Read More

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AAV-mediated delivery of actoxumab and bezlotoxumab results in serum and mucosal antibody concentrations that provide protection from C. difficile toxin challenge.

Gene Ther 2021 Feb 19. Epub 2021 Feb 19.

Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.

Clostridium difficile is the leading cause of antibiotic-associated nosocomial diarrhea in the developed world. When the host-associated colon microbiome is disrupted by the ingestion of antibiotics, C. difficile spores can germinate, resulting in infection. Read More

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February 2021

Detection and pathogenic potential of in commercial meat and meat products in Brazil.

Food Sci Technol Int 2021 Feb 11:1082013221992665. Epub 2021 Feb 11.

Food Science Department, University of Campinas, Campinas, Brazil.

The aims of this study were to evaluate the occurrence of lostridium in commercial raw meat and meat products commercialized in Brazil, and to determine the pathogenic potential and antimicrobial susceptibility of the isolates. After selective enrichment, the isolation of involved plating with and without an alcohol shock treatment onto moxalactam agar (CDMNA). The toxigenic profile was determined through PCR for detection of and genes and an enzyme-linked immunosorbent assay for toxin A/B. Read More

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February 2021

Molecular characterization of Clostridioides difficile ribotype 027 in a major Chinese hospital.

J Microbiol Immunol Infect 2021 Jan 28. Epub 2021 Jan 28.

Department of Laboratory Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China. Electronic address:

Background: The rapid spread of C. difficile 027 has become one of the leading threats of healthcare-associated infections wordwild. However, C. Read More

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January 2021

Functional analyses of epidemic Clostridioides difficile toxin B variants reveal their divergence in utilizing receptors and inducing pathology.

PLoS Pathog 2021 01 28;17(1):e1009197. Epub 2021 Jan 28.

Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, China.

Clostridioides difficile toxin B (TcdB) is a key virulence factor that causes C. difficile associated diseases (CDAD) including diarrhea and pseudomembranous colitis. TcdB can be divided into multiple subtypes/variants based on their sequence variations, of which four (TcdB1-4) are dominant types found in major epidemic isolates. Read More

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January 2021

High levels of toxigenic contamination of hospital environments: a hidden threat in hospital-acquired infections in Kenya.

Access Microbiol 2020 18;2(12):acmi000171. Epub 2020 Sep 18.

United States Army Medical Research Directorate - Africa, PO Box 606-00621, Nairobi, Kenya.

Introduction: The contribution of (formerly ) to the burden of hospital-associated infections (HAIs) remains undetermined in many African countries.

Aim: This study aimed to identify a sensitive and readily adaptable detection assay and to evaluate the HAI risk in Kenya.

Methodology: Sterile swabs in neutralizing buffer were used to sample equipment or surfaces that patients and clinical staff touched frequently. Read More

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September 2020

Molecular Epidemiology and Risk Factors of ST81 Infection in a Teaching Hospital in Eastern China.

Front Cell Infect Microbiol 2020 23;10:578098. Epub 2020 Dec 23.

Department of Laboratory Medicine, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China.

Background: The prevalence of causes an increased morbidity and mortality of inpatients, especially in Europe and North America, while data on infection (CDI) are limited in China.

Methods: From September 2014 to August 2019, 562  isolates were collected from patients and screened for toxin genes. Multilocus sequence typing (MLST) and antimicrobial susceptibility tests by E-test and agar dilution method were performed. Read More

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Dogs are carriers of Clostridioides difficile lineages associated with human community-acquired infections.

Anaerobe 2021 Feb 6;67:102317. Epub 2021 Jan 6.

Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C, Denmark. Electronic address:

There is an increasing concern about the role of animals as reservoirs of Clostridioides difficile. In this study, we investigated prevalence, antimicrobial resistance and zoonotic potential of C. difficile in dogs. Read More

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February 2021

Isolation and characterization of a multidrug-resistant toxinotype V from municipal wastewater treatment plant.

J Environ Health Sci Eng 2020 Dec 26;18(2):1281-1288. Epub 2020 Sep 26.

Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, PO Box: 14155-6446, Tehran, Iran.

Purpose: Wastewater treatment plant (WWTP) is regarded as a potential source for transmission of from urban areas into the surface water, through feces of human and animals. The aim of this study was to screen and characterize the bacteria in inlet and outlet wastewater of different WWTPs in Tehran, Iran.

Methods: Totally, 72 samples were collected from three different WWTPs (inlet site and outlet sites) during a year. Read More

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December 2020

Extra-Intestinal Effects of Toxin A and B: An In Vivo Study Using the Zebrafish Embryo Model.

Cells 2020 12 1;9(12). Epub 2020 Dec 1.

Department of Medical, Surgery and Health Sciences, University of Trieste, 34149 Trieste, Italy.

infection (CDI) is not a merely "gut-confined" disease as toxemia could drive the development of CDI-related extra-intestinal effects. These effects could explain the high CDI-associated mortality, not just justified by diarrhea and dehydration. Here, the extra-intestinal effects of toxin A (TcdA) and B (TcdB) produced by have been studied in vivo using the zebrafish embryo model. Read More

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December 2020

Receptor Binding Domains of TcdB from for Chondroitin Sulfate Proteoglycan-4 and Frizzled Proteins Are Functionally Independent and Additive.

Toxins (Basel) 2020 11 24;12(12). Epub 2020 Nov 24.

Institute of Toxicology, Hannover Medical School, 30625 Hannover, Germany.

Toxin B (TcdB) produced by is a main pathogenicity factor that affects a variety of different cell types within the colonic mucosa. TcdB is known to utilize frizzled-1,2,7 and chondroitin sulfate proteoglycan-4 (CSPG4) as protein receptors. By using human cervical cancer cell line HeLa CSPG4 knockout (CSPG4) cells as well as TcdB mutants which do not bind to either CSPG4 or frizzled-1,2,7, or both, we evaluated the impact of the individual receptors for cytopathic and cytotoxic effects of TcdB. Read More

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November 2020

An Outbreak of () Infections within an Acute and Long-Term Care Wards Due to Moxifloxacin-Resistant PCR Ribotype 176 Genotyped as PCR Ribotype 027 by a Commercial Assay.

J Clin Med 2020 Nov 20;9(11). Epub 2020 Nov 20.

Department of Medical Microbiology, Charles University, 2nd Faculty of Medicine and Motol University Hospital, 150 06 Prague, Czech Republic.

We aimed to characterize isolates cultured during a six-month single-center study from stool samples of patients with infection (CDI) genotyped by the Xpert/Epi assay by polymerase chain reaction (PCR) ribotyping, toxin genes' detection and multi-locus variable number tandem repeats analysis (MLVA). The susceptibility to metronidazole, vancomycin and moxifloxacin was determined by agar dilution. In addition, the presence of Thr82Ile in the GyrA and a single nucleotide deletion at position (Δ117) in the gene were investigated. Read More

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November 2020

Advantages of Lateral Flow Assays Based on Fluorescent Submicrospheres and Quantum Dots for Toxin B Detection.

Toxins (Basel) 2020 11 19;12(11). Epub 2020 Nov 19.

School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China.

colitis is caused by a cytotoxin produced by the anaerobic bacteria in the epithelial cells of the large intestine, particularly toxin B (TcdB). However, the sensitivity of currently utilized endotoxin determination methods has been called into question, and, therefore, more accurate and convenient detection methods are needed. Our study is the first to systematically compare fluorescent submicrosphere-based and quantum-dot nanobead-based lateral fluidity measurement methods (FMs-LFA and QDNBs-LFA) with toxin B quantification in fecal samples via sandwich analysis. Read More

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November 2020

Low Density Lipoprotein Receptor-Related Protein-1 (LRP1) Is Involved in the Uptake of Toxin A and Serves as an Internalizing Receptor.

Front Cell Infect Microbiol 2020 19;10:565465. Epub 2020 Oct 19.

Institutes for Toxicology, Hannover Medical School, Hannover, Germany.

Toxin producing strains cause gastrointestinal infections with the large glucosylating protein toxins A (TcdA) and B (TcdB) being major virulence factors responsible for the onset of symptoms. TcdA and TcdB enter their target cells receptor-mediated endocytosis. Inside the cell, the toxins glucosylate and thereby inactivate small GTPases of the Rho-/Ras subfamilies resulting in actin reorganization and cell death. Read More

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Molecular characterization of pathogenicity locus (PaLoc) and tcdC genetic diversity among tcdABClostridioides difficile clinical isolates in Tehran, Iran.

Anaerobe 2020 Dec 9;66:102294. Epub 2020 Nov 9.

Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Clostridioides difficile is the main cause of healthcare-associated diarrhea worldwide. It is proposed that certain C. difficile toxinotypes with distinct pathogenicity locus (PaLoc) variants are associated with disease severity and outcomes. Read More

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December 2020

Cost Consequences for the NHS of Using a Two-Step Testing Method for the Detection of with a Point of Care, Polymerase Chain Reaction Test as the First Step.

Diagnostics (Basel) 2020 Oct 14;10(10). Epub 2020 Oct 14.

NIHR Newcastle In Vitro Diagnostics Co-operative, Room M2.088, Translational and Clinical Research Institute, William Leech Building, Medical School, Newcastle University, Newcastle NE2 4HH, UK.

infection (CDI) is a common healthcare-associated infection. Current practice for diagnosing CDI in the Newcastle upon Tyne Hospitals NHS Foundation Trust involves a three-step, laboratory testing strategy using glutamate dehydrogenase (GDH) enzyme immunoassay (EIA), followed by a polymerase chain reaction (PCR) test then a toxin EIA. However, a PCR point of care test (POCT) for the tcdB gene for screening suspected CDI cases, may provide a more efficient way of facilitating an equally effective, two-step, testing strategy with a toxin EIA. Read More

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October 2020