Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Más filtros

Base de datos
Intervalo de año de publicación
Food Microbiol ; 85: 103280, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31500706


Listeria monocytogenes causes severe diseases in humans, including febrile gastroenteritis and systemic infections that has a high mortality despite antibiotic treatment. This pathogen may cause massive outbreaks associated to the consumption of contaminated food products, which highlight its importance in public health. In the last decade, L. monocytogenes has emerged as a foodborne pathogen of major importance in Chile. A previous work showed that in Chile during 2008 and 2009, L. monocytogenes serotypes 1/2a, 1/2b and 4b were the most frequently identified in food and clinical strains. Here we report the molecular characterization of L. monocytogenes strains isolated from 2008 to 2017 in the country. Our results indicate that serotypes 1/2a, 1/2b and 4b continue to be the most commonly found in food products. In addition, we identify persistent and widespread PFGE subtypes. This study reports ten years of epidemiological surveillance ofL. monocytogenes in Chile.

Monitoreo Epidemiológico , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos/epidemiología , Listeria monocytogenes/genética , Listeriosis/epidemiología , Chile/epidemiología , Recuento de Colonia Microbiana , ADN Bacteriano/genética , Brotes de Enfermedades , Enfermedades Transmitidas por los Alimentos/microbiología , Gastroenteritis/epidemiología , Gastroenteritis/microbiología , Variación Genética , Humanos , Listeria monocytogenes/patogenicidad , Productos de la Carne/microbiología , Epidemiología Molecular , Salud Pública , Serogrupo , Serotipificación , Factores de Virulencia/genética
Front Immunol ; 9: 1166, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29896196


Chronic intestinal inflammations are triggered by genetic and environmental components. However, it remains unclear how specific changes in the microbiota, host immunity, or pathogen exposure could promote the onset and exacerbation of these diseases. Here, we evaluated whether Salmonella enterica serovar Typhimurium (S. Typhimurium) infection increases the susceptibility to develop intestinal inflammation in mice. Two mouse models were used to evaluate the impact of S. Typhimurium infection: the chemical induction of colitis by dextran sulfate sodium (DSS) and interleukin (IL)-10-/- mice, which develop spontaneous intestinal inflammation. We observed that S. Typhimurium infection makes DSS-treated and IL-10-/- mice more susceptible to develop intestinal inflammation. Importantly, this increased susceptibility is associated to the ability of S. Typhimurium to persist in liver and spleen of infected mice, which depends on the virulence proteins secreted by Salmonella Pathogenicity Island 2-encoded type three secretion system (TTSS-2). Although immunization with a live attenuated vaccine resulted in a moderate reduction of the IL-10-/- mice susceptibility to develop intestinal inflammation due to previous S. Typhimurium infection, it did not prevent bacterial persistence. Our results suggest that persistent S. Typhimurium infection may increase the susceptibility of mice to develop inflammation in the intestine, which could be associated with virulence proteins secreted by TTSS-2.

Proteínas Bacterianas/inmunología , Colitis/inmunología , Predisposición Genética a la Enfermedad , Interleucina-10/deficiencia , Intestinos , Proteínas de la Membrana/inmunología , Infecciones por Salmonella , Salmonella typhimurium , Animales , Proteínas Bacterianas/genética , Colitis/genética , Colitis/microbiología , Colitis/patología , Sulfato de Dextran/toxicidad , Inflamación/inducido químicamente , Inflamación/genética , Inflamación/inmunología , Inflamación/microbiología , Interleucina-10/inmunología , Intestinos/inmunología , Intestinos/patología , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Infecciones por Salmonella/genética , Infecciones por Salmonella/inmunología , Infecciones por Salmonella/patología , Salmonella typhimurium/inmunología , Salmonella typhimurium/patogenicidad , Factores de Virulencia/genética , Factores de Virulencia/inmunología
Front Immunol ; 8: 191, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28293241


Inflammatory bowel disease (IBD) includes a set of pathologies that result from a deregulated immune response that may affect any portion of the gastrointestinal tract. The most prevalent and defined forms of IBD are Crohn's disease and ulcerative colitis. Although the etiology of IBD is not well defined, it has been suggested that environmental and genetic factors contribute to disease development and that the interaction between these two factors can trigger the pathology. Diet, medication use, vitamin D status, smoking, and bacterial infections have been proposed to influence or contribute to the onset or development of the disease in susceptible individuals. The infection with pathogenic bacteria is a key factor that can influence the development and severity of this disease. Here, we present a comprehensive review of studies performed in human and mice susceptible to IBD, which supports the notion that infection with bacterial pathogens, such as Salmonella, could promote the onset of IBD due to permanent changes in the intestinal microbiota, disruption of the epithelial barrier and alterations of the intestinal immune response after infection.