Virulence profile of Escherichia coli O157 strains isolated from surface water in cattle breeding areas.

Shiga toxin-producing Escherichia coli (STEC) O157:H7 is a worldwide concern. Cattle are their main reservoir and may contaminate watercourses through manure. We characterized a collection of 38 STEC O157:H7 strains isolated from surface water in feedlots areas (puddles inside pens formed after the rainfall or by spill around drinking troughs, and small water courses and lagoons, formed by runoff). Nineteen (50·0%) strains harboured stx2a /stx2c genes, 18 (47·4%) stx2c and one stx1a /stx2c . All strains harboured eae, ehxA, rfbO157 and fliCH7 genes, and the putative virulence determinants ECSP_0242, ECSP_2687 and ECSP_3620. All isolates tested as Lineage I/II by lineage-specific polymorphism assay-6. Nineteen (50%) belonged to the high virulent clade 8. The q21 allele was found in all strains and q933 /q21 alleles in 17 (44·7%). By XbaI-pulsed-field gel electrophoresis, 29 strains were grouped into seven clusters. Four clusters grouped isolates from distant places separated by 150-250 km. This may be related to vectors, like birds, involved in their spread. Otherwise, three clusters contained isolates recovered at same places with intervals of 1-9 months. This could be explained by the high environmental persistence of STEC O157:H7. These strains recovered from surface water showed similar genotypes to those found in the bovine reservoir and in human diseases, and could be linked to the high incidence of haemolytic uremic syndrome in Argentina. SIGNIFICANCE AND IMPACT OF THE STUDY: The challenge for the growing global demand for food is to find sustained production strategies without collateral effects. Intensive livestock operations generate large volumes of manure that can contaminate a finite resource, the water. This study shows how water contaminated by confined feeding operations can transport dangerous pathogens and warns to pay more attention to control and sanitation systems to prevent this type of pollution.

Shiga toxin-producing Escherichia coli (STEC) O22:H8 isolated from cattle reduces E. coli O157:H7 adherence in vitro and in vivo.

PROBLEM ADDRESSED: Shiga toxin-producing Escherichia coli (STEC) are a group of bacteria responsible for food-associated diseases. Clinical features include a wide range of symptoms such as diarrhea, hemorrhagic colitis and the hemolytic uremic syndrome (HUS), a life-threatening condition. OBJECTIVE: Our group has observed that animals naturally colonized with STEC strains of unknown serotype were not efficiently colonized with E. coli O157:H7 after experimental infection. In order to assess the basis of the interference, three STEC strains were isolated from STEC persistently-colonized healthy cattle from a dairy farm in Buenos Aires, Argentina. METHODS AND RESULTS: The three isolated strains are E. coli O22:H8 and carry the stx1 and stx2d genes. The activatable activity of Stx2d was demonstrated in vitro. The three strains carry the adhesins iha, ehaA and lpfO113. E. coli O22:H8 formed stronger biofilms in abiotic surface than E. coli O157:H7 (eae+, stx2+) and displayed a more adherent phenotype in vitro towards HeLa cells. Furthermore, when both serotypes were cultured together O22:H8 could reduce O157:H7 adherence in vitro. When calves were intragastrically pre-challenged with 108 CFU of a mixture of the three STEC strains and two days later challenged with the same dose of the strain E. coli O157:H7 438/99, the shedding of the pathogen was significantly reduced. CONCLUSIONS: These results suggest that E. coli O22:H8, a serotype rarely associated with human illness, might compete with O157:H7 at the bovine recto-anal junction, making non-O157 carrying-calves less susceptible to O157:H7 colonization and shedding of the bacteria to the environment.

Articulando la academia con la intervención comunitaria en salud mental: experiencia desde una terapia ocupacional social / Articulating the academy with community intervention in mental health: the experience from a socialoccupational therapy

Este documento sistematiza la experiencia desarrollada por el equipo docente de la escuela de Terapia Ocupacional, los estudiantes y los equipos de salud mental del Servicio de Salud Talcahuano, en los cuales se han instalado Terapeutas Ocupacionales para desarrollar funciones docentes asistenciales, en el marco de un convenio Marco entre ambas instituciones. Desde una epistemología socioconstruccionista, se presentan los fundamentos de una Terapia Ocupacional Social, al mismo tiempo, se describe una metodología de trabajo, basada en un instrumento para la intervención social, denominado Diagnóstico situacional. En este caso aplicado al campo de la salud mental, desde la Terapia Ocupacional (TO) Social. La experiencia otorga una visión compleja sobre los desafíos que se presentan en el ejercicio de la Terapia Ocupacional Social, rescatando los elementos éticos-políticos de esta perspectiva y su materialización, en consideración a los diversos actores e intereses involucrados en la construcción y configuración de los problemas que los sujetos de intervención, equipos de trabajo y estudiantes deben enfrentar. Se concluye con algunos de los principales logros y metas alcanzados con esta propuesta, destacando la posibilidad de encontrar espacios de transformación social, cuando se articulan adecuadamente las miradas de los actores...

This document systematizes the experience developed by the faculty of the School of Occupational Therapy, students and mental health teams Talcahuano Health Service, in which are installed care Occupational Therapists to develop teaching duties as part of a Framework agreement between the two institutions. From a social constructionist epistemology, the foundations of Occupational Therapy Social occur at the same time, a methodology, based on an instrument for social intervention, called Situational diagnosis is described. In this case applied to the field of mental health, since the Occupational Therapy (OT) Social. The experience gives a complex insight into the challenges that arise in the exercise of Social Occupational Therapy, rescuing this ethical-political perspective and its realization, considering the various actors and interests involved in the construction and configuration of the elements problems that subjects intervention teams and students must face. It concludes with some major accomplishments and goals achieved with this proposal, noting the possibility of finding spaces for social transformation, when the eyes of the actors adequately articulated...

Hacia la construcción de las prácticas comunitarias de terapeutas ocupacionales en Chile, desde una mirada socio histórica, desde 1972 hasta la actualidad / Towards the construction of the occupational therapists community practices in Chile, from a social historic view, from 1972 until nowadays

Esta investigación, muestra la construcción de prácticas de Terapeutas Ocupacionales que, desde diversas perspectivas, han realizado trabajo comunitario en Chile, pretendiendo comprender su desarrollo en distintos contextos históricos desde 1972 hasta la actualidad, rescatando relatos en base a la experiencia, que den cuenta de la relación entre contextos socio históricos y prácticas comunitarias. La metodología utilizada para este estudio fue cualitativa. Se recopiló información mediante once entrevistas semiestructuradas y un grupo de discusión. Posteriormente, se analizó la información a través de Teoría Fundada, en diferentes categorías, abierta y axial con un eje central en discusión con planteamientos teóricos. Los hallazgos de este estudio, permiten concluir que los contextos socio históricos determinan las formas de hacer prácticas comunitarias en Chile; y éstas, a su vez, influyen en la interacción con la comunidad favoreciendo o dificultando su participación social. El Terapeuta Ocupacional es parte de ese contexto sociohistórico por lo que su identidad, equipo de trabajo y su práctica comunitaria está configurada y construida desde ahí, sin embargo, el no hacer consciente sus prácticas y cómo éstas se han construido, no permitiría establecer la dimensión política de su hacer. Ocuparse de la ocupación, junto con la cotidianeidad en el campo comunitario implica una comprensión de la realidad socio-histórica, determinando las prácticas comunitarias de los Terapeutas Ocupacionales así como la construcción de comunidad.

This investigation will show the process of constructing Occupational Therapy practices that have been realized from various perspectives via community work in Chile, attempting to understand its development in the different social and historical periods since 1972 until the present time, emphasizing experience accounts, wich make clear the relation between social and historical contexts and practices. The methodology employed in this work was qualitative with information based on eleven semi-structured interviews and a discussion group. The information was analyzed using the Grounded Theory, through opened and axial categories, related to a central theoretical axis. The findings conclude that the social and historical contexts determine the way of doing community practice in Chile, and these affect the interaction with community, favoring or making difficult their social participation. The therapist is part of that social and historical context. Therefore, his identity, work team and community practice are constructed there. Nevertheless, if he does not become conscious of his practice and how it has been constructed, he will not build the political dimension of his work. To be in charge of daily occupation in the community field involves an understanding of the social and historical reality, determining the community practices of the Occupational Therapists and likewise the construction of community.