Detection of Shiga toxin-producing Escherichia coli in dairy cows: genetic characterization and inhibition of adherence by cattle anti-STEC antibodies to HEp-2 cell.

Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen associated with severe disease. Cattle are recognized as the primary animal reservoir of STEC. This study reports the occurrence and characterization of STEC from dairy cows and evaluates the inhibition of adherence by cattle anti-STEC antibodies to the HEp-2 cell.

Transcription levels of hes and their involvement in the biofilm formation of Shiga toxin-producing Escherichia coli O91.

Shiga toxin-producing Escherichia coli (STEC) are recognized as being responsible for many cases of foodborne diseases worldwide. Cattle are the main reservoir of STEC, shedding the microorganisms in their feces. The serogroup STEC O91 has been associated with hemorrhagic colitis and hemolytic uremic syndrome.

Antimicrobial activity of Lactiplantibacillus plantarum against shiga toxin-producing Escherichia coli.

Aims: The aim of the present work was to characterize the Lactiplantibacillus sp. LP5 strain, isolated from pork production, and identify bacteriocin-like inhibitory substances produced by this strain.

Methods And Results: In this study, LP5 was identified by species-specific PCR and 16S rRNA sequencing.

Expression of hes, iha, and tpsA codified in locus of adhesion and autoaggregation and their involvement in the capability of shiga toxin-producing Escherichia coli strains to adhere to epithelial cells.

Objectives: Shiga toxin-producing Escherichia coli strains LAA-positive are important cause of human infection. The capability to adhere to epithelial cells is a key virulence trait, and genes codified in LAA pathogenicity island could be involved in the adhesion during the pathogenesis of LAA-positive STEC strains. Thus, our objectives were to compare hes-negative and hes-positive STEC strains in their adherence capability to epithelial cells (HEp-2) and to evaluate the expression levels of the hes, iha, and tpsA in the bacteria adhered and non-adhered to HEp-2 cells.

Occurrence and genetic characterization of Shiga toxin-producing Escherichia coli on bovine and pork carcasses and the environment from transport trucks.

Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens causing severe diseases. The ability of STEC to produce disease is associated with Shiga toxin (Stx) production. We investigated the occurrence of STEC on bovine and pork carcasses and walls of trucks where they were transported, and we characterized virulence genes and serotypes of STEC strains.

Detection of Shiga Toxin-Producing (STEC) in the Endocervix of Asymptomatic Pregnant Women. Can STEC Be a Risk Factor for Adverse Pregnancy Outcomes?

The presence of in the vaginal microbiome has been associated with pregnancy complications. In previous works, we demonstrated that Shiga toxin-producing (STEC) can produce abortion and premature delivery in rats and that Shiga toxin type 2 (Stx2) can impair human trophoblast cell lines. The hypothesis of this work was that STEC may colonize the lower female reproductive tract and be responsible for adverse pregnancy outcomes.

Analysis of scenarios to reduce the probability of acquiring hemolytic uremic syndrome associated with beef consumption.

The objective of this study was to develop a quantitative microbial risk assessment (QMRA) model to evaluate potential risk mitigation strategies to reduce the probability of acquiring hemolytic uremic syndrome (HUS) associated with beef consumption in Argentina. Five scenarios were simulated to evaluate the effect of interventions on the probability of acquiring HUS from Shiga toxin-producing (STEC)-contaminated ground beef and commercial hamburger consumption. These control strategies were chosen based on previous results of the sensitivity analysis of a baseline QMRA model.

[Microbiological quality of fresh ground beef and detection of pathogens in environmental samples taken from butcher shops in the city of Tandil, Buenos Aires Province, Argentina].

The aim of this work was to evaluate the hygienic-sanitary conditions of butcher shops in Tandil, Buenos Aires Province, by estimating the risk based on good manufacturing and hygiene practices, through surveys of the establishments. The analysis was performed using a scale of 1-100, and classifying them as high risk (0-40), moderate risk (41-70) or low risk (71-100). The presence of Salmonella spp.

Genetic features of verotoxigenic Escherichia coli O157:H7 isolated from clinical cases of Argentina and Chile.

We aimed to compare the genetic diversity existing in VTEC O157:H7 strains isolated from cases of human disease from Argentina and Chile. For it, 76 strains were studied in relation to the distribution of genes encoding virulence factors and subtyped by lineage-specific polymorphisms (LSPA-6), and phylogroups assignment. Our results show the almost exclusive circulation of VTEC O157:H7 isolates belonging to lineage I/II, associated with hypervirulent strains, and to the phylogroup E and, on the other hand, genetic diversity present among Argentinean and Chilean strains analyzed, mainly in relation to putative virulence determinants and nle profiles.

Diversity of Non-O157 Shiga Toxin-Producing Isolated from Cattle from Central and Southern Chile.

Cattle are the main reservoir of Shiga toxin-producing (STEC), one of the world's most important foodborne pathogens. The pathogen causes severe human diseases and outbreaks. This study aimed to identify and characterize non-O157 STEC isolated from cattle feces from central and southern Chile.

Biofilm formation by LEE-negative Shiga Toxin-Producing Escherichia coli strains.

Shiga toxin-producing Escherichia coli (STEC) include several serotypes isolated from cases of hemorrhagic colitis and, hemolytic uremic syndrome. Although O157:H7 is the most predominant STEC serotype, more than 100 non-O157 serogroups cause diseases in humans. Some STEC carry a Locus of Enterocyte Effacement (LEE-positive); however, STEC that do not carry LEE (LEE-negative) have also been associated with illness, mainly those harbouring the Locus of Adhesion and Autoaggregation (LAA).

Distribution of Locus of Adhesion and Autoaggregation and hes Gene in STEC Strains from Countries of Latin America.

Shiga toxin-producing Escherichia coli (STEC) are zoonotic food pathogens associated with foodborne diarrheal illness, hemorrhagic colitis, and complications such as hemolytic uremic syndrome (HUS). The ability to adhere to epithelial cells is an important virulence trait, and pathogenicity islands (PAIs) play an important role on it. Some STEC carrying a PAI named locus of enterocyte effacement (LEE-positive) have been frequently associated to HUS; however, STEC that do not carry LEE (LEE-negative) have also been associated with this outcome.

Identification and detection of subtypes in LEE-negative Shiga toxin-producing (STEC) strains isolated from humans, cattle and food.

LEE-negative Shiga toxin-producing (STEC) strains are important cause of infection in humans and they should be included in the public health surveillance systems. Some isolates have been associated with haemolytic uremic syndrome (HUS) but the mechanisms of pathogenicity are is a field continuos broadening of knowledge. The IrgA homologue adhesin (Iha), encoded by , is an adherence-conferring protein and also a siderophore receptor distributed among LEE-negative STEC strains.

Cumulative acquisition of pathogenicity islands has shaped virulence potential and contributed to the emergence of LEE-negative Shiga toxin-producing Escherichia coli strains.

Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens causing severe gastroenteritis, which may lead to hemolytic uremic syndrome. The Locus of Enterocyte Effacement (LEE), a Pathogenicity Island (PAI), is a major determinant of intestinal epithelium attachment of a group of STEC strains; however, the virulence repertoire of STEC strains lacking LEE, has not been fully characterized. The incidence of LEE-negative STEC strains has increased in several countries, highlighting the relevance of their study.

Virulence genes and genetic diversity assessment of Shiga toxin-producing Escherichia coli O91 strains from cattle, beef and poultry products.

Shiga toxin-producing Escherichia coli (STEC) O91 has ranked in the top five of the non-O157 serogroups most frequently associated with human cases. In order to gain insight into the genetic diversity of O91 Latin American STEC strains, we analyzed their virulence properties and carried out a subtyping assay. A panel of 21 virulence genetic markers associated with human and animal infections was evaluated and the relatedness among strains was determined by a multiple-locus variable-number tandem repeats analysis (MLVA) comprising 9 VNTR loci.

First report of the distribution of Locus of Adhesion and Autoaggregation (LAA) pathogenicity island in LEE-negative Shiga toxin-producing Escherichia coli isolates from Argentina.

Shiga toxin-producing Escherichia coli (STEC) are important foodborne pathogens that can cause severe disease. The ability to adhere to epithelial cells is an important virulence trait and pathogenicity islands (PAIs) play an important role. Recently, researchers identified a member of the Heat-resistant agglutinin family and characterized this antigen named Hemagglutinin from Shiga toxin-producing E.

Detection and Characterization of Serotypes in the Production Chain of Two Pig Farms in Buenos Aires Province, Argentina.

The aim of the present study was to determine the prevalence of in the pork production chain and to characterize isolates. From 764 samples, 35 (4.6%) were positive for spp.

Zoonotic Potential and Antibiotic Resistance of Escherichia coli in Neonatal Calves in Uruguay.

Escherichia coli is one of the main etiological agents of neonatal calf diarrhea (NCD). The objective of this study was to assess the presence of virulence genes, genetic diversity, and antibiotic resistance mechanisms in E. coli associated with NCD in Uruguay.

Isolation and characterization of non-O157 Shiga toxin-producing Escherichia coli from beef carcasses, cuts and trimmings of abattoirs in Argentina.

Several foods contaminated with Shiga toxin-producing Escherichia coli (STEC) are associated with human diseases. Some countries have established microbiological criteria for non-O157 STEC, thus, the absence of serogroups O26, O45, O103, O104, O111, O121, and O145 in sprouts from the European Union or ground beef and beef trimmings from the United States is mandatory. While in Argentina screening for O26, O103, O111, O145 and O121 in ground beef, ready-to-eat food, sausages and vegetables is mandatory, other countries have zero-tolerance for all STEC in chilled beef.

Detection of Integrase Gene in E. coli Isolated from Pigs at Different Stages of Production System.

Integrons are one of the genetic elements involved in the acquisition of antibiotic resistance. The aim of the present research is to investigate the presence of integrons in commensal Escherichia coli (E. coli) strains, isolated from pigs at different stages of production system and from the environment in an Argentinian farm.

Shiga toxin-producing Escherichia coli: factors involved in virulence and cattle colonization.

Shiga toxin-producing Escherichia coli (STEC) cause hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS) in humans. Outbreaks are linked to bovine food sources. STEC O157:H7 has been responsible for the most severe outbreaks worldwide.