547 research outputs found

    Rates of Mutation and Host Transmission for an Escherichia coli Clone over 3 Years

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    Although over 50 complete Escherichia coli/Shigella genome sequences are available, it is only for closely related strains, for example the O55:H7 and O157:H7 clones of E. coli, that we can assign differences to individual evolutionary events along specific lineages. Here we sequence the genomes of 14 isolates of a uropathogenic E. coli clone that persisted for 3 years within a household, including a dog, causing a urinary tract infection (UTI) in the dog after 2 years. The 20 mutations observed fit a single tree that allows us to estimate the mutation rate to be about 1.1 per genome per year, with minimal evidence for adaptive change, including in relation to the UTI episode. The host data also imply at least 6 host transfer events over the 3 years, with 2 lineages present over much of that period. To our knowledge, these are the first direct measurements for a clone in a well-defined host community that includes rates of mutation and host transmission. There is a concentration of non-synonymous mutations associated with 2 transfers to the dog, suggesting some selection pressure from the change of host. However, there are no changes to which we can attribute the UTI event in the dog, which suggests that this occurrence after 2 years of the clone being in the household may have been due to chance, or some unknown change in the host or environment. The ability of a UTI strain to persist for 2 years and also to transfer readily within a household has implications for epidemiology, diagnosis, and clinical intervention

    The Rewiring of Ubiquitination Targets in a Pathogenic Yeast Promotes Metabolic Flexibility, Host Colonization and Virulence

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    Funding: This work was funded by the European Research Council [http://erc.europa.eu/], AJPB (STRIFE Advanced Grant; C-2009-AdG-249793). The work was also supported by: the Wellcome Trust [www.wellcome.ac.uk], AJPB (080088, 097377); the UK Biotechnology and Biological Research Council [www.bbsrc.ac.uk], AJPB (BB/F00513X/1, BB/K017365/1); the CNPq-Brazil [http://cnpq.br], GMA (Science without Borders fellowship 202976/2014-9); and the National Centre for the Replacement, Refinement and Reduction of Animals in Research [www.nc3rs.org.uk], DMM (NC/K000306/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Acknowledgments We thank Dr. Elizabeth Johnson (Mycology Reference Laboratory, Bristol) for providing strains, and the Aberdeen Proteomics facility for the biotyping of S. cerevisiae clinical isolates, and to Euroscarf for providing S. cerevisiae strains and plasmids. We are grateful to our Microscopy Facility in the Institute of Medical Sciences for their expert help with the electron microscopy, and to our friends in the Aberdeen Fungal Group for insightful discussions.Peer reviewedPublisher PD

    DNA Damage Triggers Genetic Exchange in Helicobacter pylori

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    Many organisms respond to DNA damage by inducing expression of DNA repair genes. We find that the human stomach pathogen Helicobacter pylori instead induces transcription and translation of natural competence genes, thus increasing transformation frequency. Transcription of a lysozyme-like protein that promotes DNA donation from intact cells is also induced. Exogenous DNA modulates the DNA damage response, as both recA and the ability to take up DNA are required for full induction of the response. This feedback loop is active during stomach colonization, indicating a role in the pathogenesis of the bacterium. As patients can be infected with multiple genetically distinct clones of H. pylori, DNA damage induced genetic exchange may facilitate spread of antibiotic resistance and selection of fitter variants through re-assortment of preexisting alleles in this important human pathogen

    Prácticas del enfermero en el contexto de la atención básica: scoping review

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    Objective: to identify and categorize the practices performed by nurses working in Primary Health Care and Family Health Strategy Units in light of responsibilities established by the profession’s legal and programmatic frameworks and by the Brazilian Unified Health System. Method: a scoping review was conducted in the following databases: LILACS, IBECS, BDENF, CINAHL and MEDLINE, and the Cochrane and SciELO libraries. Original research papers written by nurses addressing nursing practices in the primary health care context were included. Results: the review comprised 30 studies published between 2005 and 2014. Three categories emerged from the analysis: practices in the service; practices in the community; and management and education practices. Conclusion: the challenges faced by nurses are complex, as care should be centered on the population’s health needs, which requires actions at other levels of clinical and health responsibility. Brazilian nursing has achieved important advancements since the implementation of policies intended to reorganize work. There is, however, a need to shift work processes from being focused on individual procedures to being focused on patients so that an enlarged clinic is the ethical-political imperative guiding the organization of services and professional intervention.Objetivo: identificar e categorizar as práticas exercidas pelos enfermeiros junto às Unidades Básicas e às Equipes de Saúde da Família, à luz das atribuições previstas pelos marcos legais e programáticos da profissão e do Sistema Único de Saúde. Método: realizou-se uma revisão da literatura com o método scoping review, nas bases LILACS, IBECS, BDENF, CINAHL e MEDLINE, e nas bibliotecas Cochrane e SciELO. Incluíram-se artigos de pesquisa original, produzidos com enfermeiros, sobre as práticas de enfermagem no contexto dos cuidados de saúde primários. Resultados: a revisão abrangeu trinta estudos publicados entre 2005 e 2014. Da análise, resultaram três categorias: práticas no serviço, práticas na comunidade e práticas de gestão e formação. Conclusão: os desafios dos enfermeiros são complexos, posto que o cuidado deve estar centrado nas necessidades de saúde da população, o que remete à ação para outros níveis de responsabilidade clínica e sanitária. A enfermagem brasileira mostra importantes avanços desde a implantação das políticas de reorganização do trabalho. Necessita, entretanto, avançar no que se refere ao deslocamento dos processos de trabalho, focados em procedimentos individuais, para um processo mais voltado aos usuários, onde a clínica ampliada seja o imperativo ético-político da organização dos serviços e da intervenção profissional.Objetivo: identificar y categorizar las prácticas ejercidas por los enfermeros en las Unidades Básicas y los Equipos de Salud de la Familia, desde el punto de vista de las atribuciones previstas por los marcos legales y programáticos de la profesión y del Sistema Único de la Salud. Método: se realizó una revisión de la literatura con el método scoping review, en las bases LILACS, IBECS, BDENF, CINAHL y MEDLINE, y en las bibliotecas Cochrane y SciELO. Se incluyeron artículos de investigación original, producidos con enfermeros, sobre las prácticas de enfermería en el contexto de los cuidados de salud primarios. Resultados: la revisión abarcó treinta estudios publicados entre 2005 y 2014. Del análisis, resultaron tres categorías: prácticas en el servicio; prácticas en la comunidad; y, prácticas de administración y formación. Conclusión: los desafíos de los enfermeros son complejos, ya que el cuidado debe estar centrado en las necesidades de salud de la población, lo que conduce a la acción para otros niveles de responsabilidad clínica y sanitaria. La enfermería brasileña muestra importantes avances a partir de la implantación de las políticas de reorganización del trabajo. Necesita, entre tanto, avanzar en lo que se refiere al desplazamiento de los procesos de trabajo, enfocados en procedimientos individuales, para un proceso más dirigido a los usuarios, en donde la clínica ampliada sea el imperativo ético político de la organización de los servicios y de la intervención profesional.info:eu-repo/semantics/publishedVersio
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