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.

Detection of EPEC and STEC strains isolated from children with diarrhea in Argentina.

Rectal swabs (122) from pediatric patients were analyzed by polymerase chain reaction (PCR) for the detection of EPEC and STEC. STEC isolates were tested for the presence of stx1, stx2, eae, saa and ehxA. All eae-positive samples were tested for the presence of bfpA, and antigen O was determined using the agglutination test.

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.

Molecular and Genetic Characterization of Colicinogenic Strains Active against Shiga Toxin-Producing O157:H7.

The objective of this work was to molecularly and genotypically characterize and test the inhibitory activity of six colicinogenic strains (ColEc) and their partially purified colicins against STEC O157:H7 isolated from clinical human cases. Inhibition tests demonstrated the activity of these strains and their colicins against STEC O157:H7. By PCR it was possible to detect colicins Ia, E7, and B and microcins M, H47, C7, and J25.

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.

Safety and Immunogenicity of a Chimeric Subunit Vaccine against Shiga Toxin-Producing in Pregnant Cows.

Shiga toxin-producing (STEC) is a zoonotic pathogen that causes gastroenteritis and Hemolytic Uremic Syndrome. Cattle are the main animal reservoir, excreting the bacteria in their feces and contaminating the environment. In addition, meat can be contaminated by releasing the intestinal content during slaughtering.

[Shiga toxin producing Escherichia coli: the challenge of adherence to survive].

Shiga Toxin-producing Escherichia coli (STEC) is recognized as being responsible for a large number of foodborne illnesses around the world. The pathogenicity of STEC has been related to Stx toxins. However, the ability of STEC to colonize the host and other surfaces can be essential for developing its pathogenicity.

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.

Protective effect of LP5 in a murine model of colonisation by DSPV458.

Thermotolerant species are the leading cause of foodborne bacterial diarrheal disease worldwide. , abundant in pigs and pork products, have been identified as a source of human infection. In this study, we propose the use of LP5 as a probiotic to reduce colonisation of this intestinal pathogen in a murine colonisation model of DSPV458.

[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.

Quantitative risk assessment of haemolytic uremic syndrome associated with beef consumption in Argentina.

We developed a quantitative microbiological risk assessment (QMRA) of haemolytic uremic syndrome (HUS) associated with Shiga toxin-producing Escherichia coli (STEC)-contaminated beef (intact beef cuts, ground beef and commercial hamburgers) in children under 15 years of age from Argentina. The QMRA was used to characterize STEC prevalence and concentration levels in each product through the Argentinean beef supply chain, including cattle primary production, cattle transport, processing and storage in the abattoir, retail and home preparation, and consumption. Median HUS probability from beef cut, ground beef and commercial hamburger consumption was <10-15, 5.

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.

[Molecular characterization of Shiga toxin producing Escherichia coli isolated from 2 livestock establishments of Paraguay].

Shiga toxin-producing Escherichia coli (STEC) is a food-borne pathogen in humans, with cattle being the main reservoir. The objective of this study was to determine the carrying of STEC in Paraguayan bovines and to analyze the virulence profile and serotypes of these isolates. A total of 197 samples of bovine fecal samples and an average of 5 to 50 colonies from stx/stx positive samples were studied.

[Effects of the culture medium and the methodology applied on the biofilm formation of 2diarrheagenic Escherichia coli strains].

The ability to form biofilms of pathogenic microorganisms in a wide variety of environments, surfaces and conditions constitute an important risk, both for the food industry and for public health. The aim of this work was to evaluate and to compare the effects of the methodology applied and the culture medium used on the ability of a non-O157 verotoxigenic Escherichia coli strain and an enteropathogenic strain to form biofilm on polystyrene surface. Two methodological variants were tested in static culture and culture mediums with different composition were used.

Antimicrobial Resistance in Class 1 Integron-Positive Shiga Toxin-Producing Isolated from Cattle, Pigs, Food and Farm Environment.

The aim of this study was to investigate the presence of class 1 integrons in a collection of Shiga toxin-producing (STEC) from different origins and to characterize pheno- and genotypically the antimicrobial resistance associated to them. A collection of 649 isolates were screened for the class 1 integrase gene () by Polymerase chain reaction The variable region of class 1 integrons was amplified and sequenced. Positive strains were evaluated for the presence of antimicrobial resistance genes with microarray and for antimicrobial susceptibility by the disk diffusion method.

Development of gluten-free muffins utilizing squash seed dietary fiber.

Gluten-free muffins with squash seed flour (SSF) were developed for contribute to reduce nutritional deficiencies and improving the health of the celiac population. Physicochemical and sensory properties of muffins were evaluated. SSF was incorporated at two levels (10 and 20% w/w) in commercial gluten-free premix (control).

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.

Variation in the Distribution of Putative Virulence and Colonization Factors in Shiga Toxin-Producing Isolated from Different Categories of Cattle.

Shiga toxin-producing (STEC) are pathogens of significant public health concern. Several studies have confirmed that cattle are the main reservoir of STEC in Argentina and other countries. Although Shiga toxins represent the primary virulence factors of STEC, the adherence and colonization of the gut are also important in the pathogenesis of the bacteria.

α-Galactosides present in lupin flour affect several metabolic parameters in Wistar rats.

The aim of this study is to evaluate the influence of α-galactosides present in a lupin diet on metabolic parameters in growing Wistar rats. Lupin (Lupinus albus) is a rich source of non-digestible carbohydrates called α-galactosides whose beneficial health effects have been widely reported. For our investigation, twenty male Wistar rats were fed with two different diets: control (C) and lupin flour (L) for a 60-day period.