Detection of cytotoxic necrotizing factor types 1 and 2 among fecal Escherichia coli isolates from brazilian children with and without diarrhea

The enteropathogenic role of cytotoxic necrotizing factor (CNF)-producing Escherichia coli was investigated by searching cnf genes among 2074 isolates from 200 children with and 200 without acute diarrhea in Brazil. Fourteen (7%) cases versus 10 (5%) control children carried at least one cnf positive isolate (P = 0.50) and most isolates expressed CNF type 1. DNA sequences of virulence factors of extraintestinal pathogenic E. coli (ExPEC) were detected in 78.6% of CNF1-producing isolates. Besides not being associated with human acute diarrhea, the CNF1-producing isolates here identified may represent potential ExPEC transitorily composing the normal intestinal flora.Instituto Adolfo Lutz Seção de BacteriologiaUniversidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM) Departamento de Microbiologia, Imunologia e ParasitologiaUNIFESP, EPM, Depto. de Microbiologia, Imunologia e ParasitologiaSciEL

Prevalence and Characteristics of the O122 Pathogenicity Island in Typical and Atypical Enteropathogenic Escherichia coli Strains

The presence of the pathogenicity island (PAI) O122 genes, efa1 (lifA), sen, pagC, nleB, and nleE, in typical and atypical enteropathogenic Escherichia coli (EPEC) strains was investigated. the simultaneous occurrence of all genes was statistically associated with diarrhea due to atypical EPEC. Detection of the complete PAI O122 could aid in the identification of potential pathogenic strains of atypical EPEC.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Dept Microbiol, São Paulo, BrazilSecao Bacteriol Inst Adolfo Lutz, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol, São Paulo, BrazilFAPESP: 08/53812-4Web of Scienc

Antibody response against plasmid-encoded toxin (Pet) and the protein involved in intestinal colonization (Pic) in children with diarrhea produced by enteroaggregative Escherichia coli

Enteroaggregative Escherichia eoli (EAEC) is an emerging cause of pediatric and adult travellers diarrhea. the mechanism by which EAEC induce diarrhea is not completely known. Two serine protease autotransporter proteins, named Pet and Pic have been identified in EAEC strains. Pet has enterotoxic and cytotoxic activities, while the role of Pic in pathogenesis may lie on its mucinolytic activity. Little is known about Pet and Pic biological activities in vivo. in this study the antibody responses against these autotransporter proteins in convalescent children is investigated. Fifteen (83%) children showed specific antibodies against Pet or Pic in their sera. IgG and IgM antibodies were the main isotype found. Specific antibodies against Pic, but not against Pet, were detected in sera from age-matched control group. These data show that specific anti-Pet and anti-Pic antibodies are produced during the course of a natural EAEC infection in children. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.Univ São Paulo, Dept Microbiol, Inst Ciencias Biomed, São Paulo, BrazilInst Butantan, Lab Especial Microbiol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilUniv São Paulo, Fac Ciencias Farmaceut, Dept Anal Clin & Toxicol, BR-05508900 São Paulo, BrazilCINVESTAV, IPN, Dept Cell Biol, Mexico City 14000, DF, MexicoUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilWeb of Scienc

Molecular and Phenotypic Characterization of Escherichia coli O26:H8 among Diarrheagenic E. coli O26 Strains Isolated in Brazil

Escherichia coli strains of serogroup O26 comprise two distinct groups of pathogens, characterized as enteropathogenic E. coli (EPEC) and enterohemorrhagic E. coli (EHEC). Among the several genes related to type III secretion system-secreted effector proteins, espK was found to be highly specific for EHEC O26:H11 and its stx-negative derivative strains isolated in European countries. E. coli O26 strains isolated in Brazil from infant diarrhea, foods, and the environment have consistently been shown to lack stx genes and are thus considered atypical EPEC. However, no further information related to their genetic background is known. Therefore, in this study, we aimed to discriminate and characterize these Brazilian O26 stx-negative strains by phenotypic, genetic, and biochemical approaches. Among 44 isolates confirmed to be O26 isolates, most displayed flagellar antigen H11 or H32. Out of the 13 nonmotile isolates, 2 tested positive for fliC(H11), and 11 were fliC(H8) positive. the identification of genetic markers showed that several O26:H11 and all O26:H8 strains tested positive for espK and could therefore be discriminated as EHEC derivatives. the presence of H8 among EHEC O26 and its stx-negative derivative isolates is described for the first time. the interaction of three isolates with polarized Caco-2 cells and with intestinal biopsy specimen fragments ex vivo confirmed the ability of the O26 strains analyzed to cause attaching-and-effacing (A/E) lesions. the O26:H32 strains, isolated mostly from meat, were considered nonvirulent. Knowledge of the virulence content of stx-negative O26 isolates within the same serotype helped to avoid misclassification of isolates, which certainly has important implications for public health surveillance.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Inst Butantan, Bacteriol Lab, São Paulo, BrazilFrench Food Safety Agcy, Maisons Alfort, FranceUniv Estadual Londrina, Dept Patol Geral, Ctr Ciencias Biomed, Londrina, Parana, BrazilUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilCtr Univ Sao Camilo, São Paulo, BrazilBfR Fed Inst Risk Assessment, Natl Reference Lab Escherichia Coli, Berlin, GermanyUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilWeb of Scienc

Geriatric Oncology as an Unmet Workforce Training Need in the United Kingdom—A Narrative Review by the British Oncology Network for Undergraduate Societies (BONUS) and the International Society of Geriatric Oncology (SIOG) UK Country Group

Cancer is a disease associated with ageing. Managing cancer in older adults may prove challenging owing to pre-existing frailty, comorbidity, and wider holistic needs, as well as the unclear benefits and harms of standard treatment options. With the ongoing advances in oncology and the increasing complexity of treating older adults with cancer, the geriatric oncology field must be a priority for healthcare systems in education, research, and clinical practice. However, geriatric oncology is currently not formally taught in undergraduate education or postgraduate training programmes in the United Kingdom (UK). In this commentary, we outline the landscape of geriatric oncology undergraduate education and postgraduate training for UK doctors. We highlight current challenges and opportunities and provide practical recommendations for better preparing the medical workforce to meet the needs of the growing population of older adults with cancer. This includes key outcomes to be considered for inclusion within undergraduate and postgraduate curricula

HeLa-cell adherence patterns and actin aggregation of enteropathogenic Escherichia coli (EPEC) and Shiga-toxin-producing E. coli (STEC) strains carrying different eae and tir alleles

A collection of 69 eae-positive strains expressing 29 different intimin types and eight tir alleles was characterized with respect to their adherence patterns to HeLa cells, ability to promote actin accumulation in vitro, the presence of bfpA alleles in positive strains, and bundle-forming pilus (BFP) expression. All of the nine typical enteropathogenic Escherichia coli (tEPEC) studied harbored the enteropathogenic E. coli adherence factor (EAF) plasmid, as shown by PCR and/or EAF probe results. In addition, they were positive for bfpA, as shown by PCR, and BFP expression, as confirmed by immunofluorescence (IFL) and/or immunoblotting (IBL) assays. Localized adherence (LA) was exclusively displayed by those nine tEPEC, while localized-adherence-like (LAL) was the most frequent pattern among atypical EPEC (aEPEC) and Shiga-toxinproducing E. coli (STEC). All LA and LAL strains were able to cause attaching and effacing (AE) lesions, as established by means of the FAS test. There was a significant association between the presence of tir allele α1 and bfpA-positive strains, and consequently, with the LA pattern. However, intimin type or bfpA was not associated with the adherence pattern displayed in HeLa cells. Among the eight bfpA alleles detected, a new type (β10; accession number FN391178) was identified in a strain of serotype O157:H45, and a truncated variant (β3.2-t; accession number FN 391181) in four strains belonging to different pathotypes. [Int Microbiol 2009; 12(4):243-251