128 research outputs found

    Molecular cloning and characterization of the structural gene for protein I, the major outer membrane protein of Neisseria gonorrhoeae.

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    Protein I (P.I) is the major outer membrane protein of Neisseria gonorrhoeae and serves as a porin. By using oligonucleotide probes derived from the known amino-terminal sequence of the mature protein, we have cloned the gene encoding the P.I of gonococcal strain FA19 in three overlapping fragments and determined the DNA sequence. The gene sequence predicts a protein with characteristics typical of the porins of other Gram-negative bacteria. A clone expressing P.I in Escherichia coli was obtained by removing a portion of the P.I gene promoter and reconstructing the entire P.I gene in a position just downstream from a phage T7 promoter. Expression of P.I was then achieved by introducing this recombinant plasmid into an E. coli strain containing an inducible T7 polymerase gene. The clone produced a protein that was identical in size to native P.I and reacted with anti-P.I monoclonal antibodies. Prolonged expression of the protein apparently was lethal for E. coli, possibly explaining failures to clone an intact P.I gene with its own promoter

    Identifying resources used by young people to overcome mental distress in three Latin American cities: a qualitative study

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    OBJECTIVE: To explore which resources and activities help young people living in deprived urban environments in Latin America to recover from depression and/or anxiety. DESIGN: A multimethod, qualitative study with 18 online focus groups and 12 online structured group conversations embedded into arts workshops. SETTING: This study was conducted in Bogotá (Colombia), Buenos Aires (Argentina) and Lima (Peru). PARTICIPANTS: Adolescents (15–16 years old) and young adults (20–24 years old) with capacity to provide assent/consent and professionals (older than 18 years of age) that had experience of professionally working with young people were willing to share personal experience within a group, and had capacity to provide consent. RESULTS: A total of 185 participants took part in this study: 111 participants (36 adolescents, 35 young adults and 40 professionals) attended the 18 focus groups and 74 young people (29 adolescents and 45 young adults) took part in the 12 arts workshops. Eight categories captured the resources and activities that were reported by young people as helpful to overcome mental distress: (1) personal resources, (2) personal development, (3) spirituality and religion, (4) social resources, (5) social media, (6) community resources, (7) activities (subcategorised into artistic, leisure, sports and outdoor activities) and (8) mental health professionals. Personal and social resources as well as artistic activities and sports were the most common resources identified that help adolescents and young adults to overcome depression and anxiety. CONCLUSION: Despite the different contexts of the three cities, young people appear to use similar resources to overcome mental distress. Policies to improve the mental health of young people in deprived urban settings should address the need of community spaces, where young people can play sports, meet and engage in groups, and support community organisations that can enable and facilitate a range of social activities

    Which resources help young people to prevent and overcome mental distress in deprived urban areas in Latin America? A protocol for a prospective cohort study

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    Introduction: Improving the mental health of young people is a global public health priority. In Latin America, young people living in deprived urban areas face various risk factors for mental distress. However, most either do not develop mental distress in the form of depression and anxiety, or recover within a year without treatment from mental health services. This research programme seeks to identify the personal and social resources that help young people to prevent and recover from mental distress. / Methods and analysis: A cross-sectional study will compare personal and social resources used by 1020 young people (aged 15–16 and 20–24 years) with symptoms of depression and/or anxiety and 1020 without. A longitudinal cohort study will follow-up young people with mental distress after 6 months and 1 year and compare resource use in those who do and do not recover. An experience sampling method study will intensively assess activities, experiences and mental distress in subgroups over short time periods. Finally, we will develop case studies highlighting existing initiatives that effectively support young people to prevent and recover from mental distress. The analysis will assess differences between young people with and without distress at baseline using t-tests and χ2 tests. Within the groups with mental distress, multivariate logistic regression analyses using a random effects model will assess the relationship between predictor variables and recovery. / Ethics and dissemination: Ethics approvals are received from Ethics Committee in Biomedical Research, Faculty of Medicine, University of Buenos Aires; Faculty of Medicine-Research and Ethics Committee of the Pontificia Universidad Javeriana, Bogotá; Institutional Ethics Committee of Research of the Universidad Peruana Cayetano Heredia and Queen Mary Ethics of Research Committee. Dissemination will include arts-based methods and target different audiences such as national stakeholders, researchers from different disciplines and the general public. / Trial registration number: ISRCTN72241383

    Highlights of the 11th International Bordetella Symposium: From basic biology to vaccine development

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    Pertussis is a severe respiratory disease caused by infection with the bacterial pathogen Bordetella pertussis. The disease affects individuals of all ages but is particularly severe and sometimes fatal in unvaccinated young infants. Other Bordetella species cause diseases in humans, animals, and birds. Scientific, clinical, public health, vaccine company, and regulatory agency experts on these pathogens and diseases gathered in Buenos Aires, Argentina from 5 to 8 April 2016 for the 11th International Bordetella Symposium to discuss recent advances in our understanding of the biology of these organisms, the diseases they cause, and the development of new vaccines and other strategies to prevent these diseases. Highlights of the meeting included pertussis epidemiology in developing nations, genomic analysis of Bordetella biology and evolution, regulation of virulence factor expression, new model systems to study Bordetella biology and disease, effects of different vaccines on immune responses, maternal immunization as a strategy to prevent newborn disease, and novel vaccine development for pertussis. In addition, the group approved the formation of an International Bordetella Society to promote research and information exchange on bordetellae and to organize future meetings. A new Bordetella.org website will also be developed to facilitate these goals.Instituto de Biotecnologia y Biologia Molecula

    Highlights of the 11th International Bordetella Symposium: From basic biology to vaccine development

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    Pertussis is a severe respiratory disease caused by infection with the bacterial pathogen Bordetella pertussis. The disease affects individuals of all ages but is particularly severe and sometimes fatal in unvaccinated young infants. Other Bordetella species cause diseases in humans, animals, and birds. Scientific, clinical, public health, vaccine company, and regulatory agency experts on these pathogens and diseases gathered in Buenos Aires, Argentina from 5 to 8 April 2016 for the 11th International Bordetella Symposium to discuss recent advances in our understanding of the biology of these organisms, the diseases they cause, and the development of new vaccines and other strategies to prevent these diseases. Highlights of the meeting included pertussis epidemiology in developing nations, genomic analysis of Bordetella biology and evolution, regulation of virulence factor expression, new model systems to study Bordetella biology and disease, effects of different vaccines on immune responses, maternal immunization as a strategy to prevent newborn disease, and novel vaccine development for pertussis. In addition, the group approved the formation of an International Bordetella Society to promote research and information exchange on bordetellae and to organize future meetings. A new Bordetella.org website will also be developed to facilitate these goals.Instituto de Biotecnologia y Biologia Molecula

    Highlights of the 11th International Bordetella Symposium: From basic biology to vaccine development

    Get PDF
    Pertussis is a severe respiratory disease caused by infection with the bacterial pathogen Bordetella pertussis. The disease affects individuals of all ages but is particularly severe and sometimes fatal in unvaccinated young infants. Other Bordetella species cause diseases in humans, animals, and birds. Scientific, clinical, public health, vaccine company, and regulatory agency experts on these pathogens and diseases gathered in Buenos Aires, Argentina from 5 to 8 April 2016 for the 11th International Bordetella Symposium to discuss recent advances in our understanding of the biology of these organisms, the diseases they cause, and the development of new vaccines and other strategies to prevent these diseases. Highlights of the meeting included pertussis epidemiology in developing nations, genomic analysis of Bordetella biology and evolution, regulation of virulence factor expression, new model systems to study Bordetella biology and disease, effects of different vaccines on immune responses, maternal immunization as a strategy to prevent newborn disease, and novel vaccine development for pertussis. In addition, the group approved the formation of an International Bordetella Society to promote research and information exchange on bordetellae and to organize future meetings. A new Bordetella.org website will also be developed to facilitate these goals.Instituto de Biotecnologia y Biologia Molecula

    Highlights of the 12th International Bordetella Symposium

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    To commemorate the 100th anniversary of the Nobel prize being awarded to Jules Bordet, the discoverer of Bordetella pertussis, the 12th International Bordetella Symposium was held from 9 to 12 April 2019 at the Universite Libre de Bruxelles, where Jules Bordet studied and was Professor of Microbiology. The symposium attracted more than 300 Bordetella experts from 34 countries. They discussed the latest epidemiologic data and clinical aspects of pertussis, Bordetella biology and pathogenesis, immunology and vaccine development, and genomics and evolution. Advanced technological and methodological tools provided novel insights into the genomic diversity of Bordetella and a better understanding of pertussis disease and vaccine performance. New molecular approaches revealed previously unrecognized complexity of virulence gene regulation. Innovative insights into the immune responses to infection by Bordetella resulted in the development of new vaccine candidates. Such discoveries will aid in the design of more effective approaches to control pertussis and other Bordetella-related diseases.Instituto de Biotecnologia y Biologia MolecularCentro de Investigación y Desarrollo en Fermentaciones Industriale

    FHA-Mediated Cell-Substrate and Cell-Cell Adhesions Are Critical for Bordetella pertussis Biofilm Formation on Abiotic Surfaces and in the Mouse Nose and the Trachea

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    Bordetella spp. form biofilms in the mouse nasopharynx, thereby providing a potential mechanism for establishing chronic infections in humans and animals. Filamentous hemagglutinin (FHA) is a major virulence factor of B. pertussis, the causative agent of the highly transmissible and infectious disease, pertussis. In this study, we dissected the role of FHA in the distinct biofilm developmental stages of B. pertussis on abiotic substrates and in the respiratory tract by employing a murine model of respiratory biofilms. Our results show that the lack of FHA reduced attachment and decreased accumulation of biofilm biomass on artificial surfaces. FHA contributes to biofilm development by promoting the formation of microcolonies. Absence of FHA from B. pertussis or antibody-mediated blockade of surface-associated FHA impaired the attachment of bacteria to the biofilm community. Exogenous addition of FHA resulted in a dose-dependent inhibitory effect on bacterial association with the biofilms. Furthermore, we show that FHA is important for the structural integrity of biofilms formed on the mouse nose and trachea. Together, these results strongly support the hypothesis that FHA promotes the formation and maintenance of biofilms by mediating cell-substrate and inter-bacterial adhesions. These discoveries highlight FHA as a key factor in establishing structured biofilm communities in the respiratory tract
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