19 research outputs found

    ß-lactamasas AmpC plasmídicas tipo CMY-2 emergentes en Tucumán, Argentina

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    En los últimos años, algunas enterobacterias como Klebsiella pneumoniae, Proteus mirabilis y Escherichia coli adquirieron resistencia a las cefalosporinas de tercera generación (C3G) por la adquisición de ß-lactamasas de tipo AmpC plasmídicas, mecanismo que se está comunicando cada vez con mayor frecuencia en el mundo. El objetivo de esta investigación fue detectar la emergencia de ß-lactamasas AmpC plasmídicas en Tucumán e identificar sus tipos predominantes. Se estudió la sensibilidad a diferentes antimicrobianos de 733 aislamientos clínicos consecutivos de enterobacterias obtenidos en el período marzo-julio de 2009 en tres centros asistenciales de nuestra provincia. Se realizaron pruebas de sensibilidad por difusión y se seleccionaron tres aislamientos de E. coli y uno de P. mirabilis resistentes a C3G y a cefoxitina. En estos aislamientos se determinó la CIM por E-test y se evaluó el mecanismo enzimático de resistencia mediante sinergia con discos de ácido aminofenilborónico y ensayo microbiológico de Masuda. Se realizó PCR usando cebadores dirigidos al grupo CIT de las AmpC plasmídicas. Se obtuvo un amplicón de 462 pb que fue secuenciado; presentó un 100% de identidad con blaCMY-2 en los cuatro aislamientos. En conclusión, las ß-lactamasas AmpC tipo CMY-2 emergieron en nuestro medio, de modo que es importante implementar una vigilancia sistemática de estas resistencias para evitar potenciales consecuencias clínicas y epidemiológicas.CMY-2-type plasmid-mediated AmpC B-Lactamases emerging in Tucumán, Argentina. In the last years, Enterobacteriaceae such as Klebsiella pneumoniae, Proteus mirabilis and Escherichia coli, have acquired resistance to third-generation cephalosporins (C3G) because of the presence of plasmid-mediated AmpC B-lactamases. The aim of this work was to detect plasmid AmpC enzymes and to investigate the predominant types in our region. Between March and July 2009, 733 consecutive isolates of Enterobacteriaceae derived from hospitals and outpatient centers were studied. Susceptibility testing was performed by disk diffusion; one P. mirabilis and three E. coli strains showed resistance to cephamycins (cefoxitin) and C3G. An E-test to determine MIC and a synergy test by aminophenylboronic disks were performed. Enzymatic activity against cefoxitin was confirmed by a microbiological assay. A polymerase chain reaction (PCR) for the detection of plasmid-mediated ampC genes of different groups was performed and a 462-bp amplicon was obtained when using primers directed against the CIT group; the obtained sequences were compared to blaCMY-2 sequences, showing 100% identity. The emergence of CMY-2-type plasmid-mediated AmpC B-lactamases indicated the importance of implementing systematic monitoring of these resistances to avoid potential clinical and epidemiological consequences.Fil: Jure, Maria Angela. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Bacteriología; ArgentinaFil: Presti, Constanza. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Bacteriología; ArgentinaFil: Cudmani, Norma M.. Hospital Avellaneda. Laboratorio de Bacteriología; ArgentinaFil: Grellet, Lidia M.. Pcia. de Tucumán. Hospital de Concepción; ArgentinaFil: López, Carolina. Centro de Microbiología Médica. Laboratorio de Bacteriología; ArgentinaFil: Musa, Eduardo H.. Centro de Microbiologia. Red WHONET, San Miguel de Tucumán; ArgentinaFil: Aulet, Olga C.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Bacteriología; ArgentinaFil: Nieto Peñalver, Carlos Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Bacteriología; ArgentinaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: de Castillo, Marta Cecilia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Bacteriología; Argentin

    Hantavirus Prevalence in the IX Region of Chile

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    An epidemiologic and seroprevalence survey was conducted (n=830) to assess proportion of persons exposed to hantavirus in IX Region Chile, which accounts for 25% of reported cases of hantavirus cardiopulmonary syndrome. This region has three geographic areas with different disease incidences and a high proportion of aboriginals. Serum samples were tested for immunoglobulin (Ig) G antibodies by enzyme-linked immunosorbent assay against Sin Nombre virus N antigen by strip immunoblot assay against Sin Nombre, Puumala, Río Mamoré, and Seoul N antigens. Samples from six patients were positive for IgG antibodies reactive with Andes virus; all patients lived in the Andes Mountains. Foresting was also associated with seropositivity; but not sex, age, race, rodent exposure, or farming activities. Exposure to hantavirus varies in different communities of IX Region. Absence of history of pneumonia or hospital admission in persons with specific IgG antibodies suggests that infection is clinically inapparent

    Highly Differentiated, Resting Gn-Specific Memory CD8+ T Cells Persist Years after Infection by Andes Hantavirus

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    In man, infection with South American Andes virus (ANDV) causes hantavirus cardiopulmonary syndrome (HCPS). HCPS due to ANDV is endemic in Southern Chile and much of Argentina and increasing numbers of cases are reported all over South America. A case-fatality rate of about 36% together with the absence of successful antiviral therapies urge the development of a vaccine. Although T-cell responses were shown to be critically involved in immunity to hantaviruses in mouse models, no data are available on the magnitude, specificity and longevity of ANDV-specific memory T-cell responses in patients. Using sets of overlapping peptides in IFN-γ ELISPOT assays, we herein show in 78 Chilean convalescent patients that Gn-derived epitopes were immunodominant as compared to those from the N- and Gc-proteins. Furthermore, while the relative contribution of the N-specific response significantly declined over time, Gn-specific responses remained readily detectable ex vivo up to 13 years after the acute infection. Tetramer analysis further showed that up to 16.8% of all circulating CD3+CD8+ T cells were specific for the single HLA-B*3501-restricted epitope Gn465–473 years after the acute infection. Remarkably, Gn465–473–specific cells readily secreted IFN-γ, granzyme B and TNF-α but not IL-2 upon stimulation and showed a ‘revertant’ CD45RA+CD27−CD28−CCR7−CD127− effector memory phenotype, thereby resembling a phenotype seen in other latent virus infections. Most intriguingly, titers of neutralizing antibodies increased over time in 10/17 individuals months to years after the acute infection and independently of whether they were residents of endemic areas or not. Thus, our data suggest intrinsic, latent antigenic stimulation of Gn-specific T-cells. However, it remains a major task for future studies to proof this hypothesis by determination of viral antigen in convalescent patients. Furthermore, it remains to be seen whether Gn-specific T cells are critical for viral control and protective immunity. If so, Gn-derived immunodominant epitopes could be of high value for future ANDV vaccines

    The Helicobacter pylori Genome Project : insights into H. pylori population structure from analysis of a worldwide collection of complete genomes

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    Helicobacter pylori, a dominant member of the gastric microbiota, shares co-evolutionary history with humans. This has led to the development of genetically distinct H. pylori subpopulations associated with the geographic origin of the host and with differential gastric disease risk. Here, we provide insights into H. pylori population structure as a part of the Helicobacter pylori Genome Project (HpGP), a multi-disciplinary initiative aimed at elucidating H. pylori pathogenesis and identifying new therapeutic targets. We collected 1011 well-characterized clinical strains from 50 countries and generated high-quality genome sequences. We analysed core genome diversity and population structure of the HpGP dataset and 255 worldwide reference genomes to outline the ancestral contribution to Eurasian, African, and American populations. We found evidence of substantial contribution of population hpNorthAsia and subpopulation hspUral in Northern European H. pylori. The genomes of H. pylori isolated from northern and southern Indigenous Americans differed in that bacteria isolated in northern Indigenous communities were more similar to North Asian H. pylori while the southern had higher relatedness to hpEastAsia. Notably, we also found a highly clonal yet geographically dispersed North American subpopulation, which is negative for the cag pathogenicity island, and present in 7% of sequenced US genomes. We expect the HpGP dataset and the corresponding strains to become a major asset for H. pylori genomics

    ß-lactamasas AmpC plasmídicas tipo CMY-2 emergentes en Tucumán, Argentina CMY-2-type plasmid-mediated AmpC ß-Lactamases emerging in Tucumán, Argentina

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    En los últimos años, algunas enterobacterias como Klebsiella pneumoniae, Proteus mirabilis y Escherichia coli adquirieron resistencia a las cefalosporinas de tercera generación (C3G) por la adquisición de ß-lactamasas de tipo AmpC plasmídicas, mecanismo que se está comunicando cada vez con mayor frecuencia en el mundo. El objetivo de esta investigación fue detectar la emergencia de ß-lactamasas AmpC plasmídicas en Tucumán e identificar sus tipos predominantes. Se estudió la sensibilidad a diferentes antimicrobianos de 733 aislamientos clínicos consecutivos de enterobacterias obtenidos en el período marzo-julio de 2009 en tres centros asistenciales de nuestra provincia. Se realizaron pruebas de sensibilidad por difusión y se seleccionaron tres aislamientos de E. coli y uno de P. mirabilis resistentes a C3G y a cefoxitina. En estos aislamientos se determinó la CIM por E-test y se evaluó el mecanismo enzimático de resistencia mediante sinergia con discos de ácido aminofenilborónico y ensayo microbiológico de Masuda. Se realizó PCR usando cebadores dirigidos al grupo CIT de las AmpC plasmídicas. Se obtuvo un amplicón de 462 pb que fue secuenciado; presentó un 100% de identidad con blaCMY-2 en los cuatro aislamientos. En conclusión, las ß-lactamasas AmpC tipo CMY-2 emergieron en nuestro medio, de modo que es importante implementar una vigilancia sistemática de estas resistencias para evitar potenciales consecuencias clínicas y epidemiológicas.In the last years, Enterobacteriaceae such as Klebsiella pneumoniae, Proteus mirabilis and Escherichia coli, have acquired resistance to third-generation cephalosporins (C3G) because of the presence of plasmid-mediated AmpC ß-lactamases. The aim of this work was to detect plasmid AmpC enzymes and to investigate the predominant types in our region. Between March and July 2009, 733 consecutive isolates of Enterobacteriaceae derived from hospitals and outpatient centers were studied. Susceptibility testing was performed by disk diffusion; one P. mirabilis and three E. coli strains showed resistance to cephamycins (cefoxitin) and C3G. An E-test to determine MIC and a synergy test by aminophenylboronic disks were performed. Enzymatic activity against cefoxitin was confirmed by a microbiological assay. A polymerase chain reaction (PCR) for the detection of plasmid-mediated ampC genes of different groups was performed and a 462-bp amplicon was obtained when using primers directed against the CIT group; the obtained sequences were compared to blaCMY-2 sequences, showing 100% identity. The emergence of CMY-2-type plasmid-mediated AmpC ß-lactamases indicated the importance of implementing systematic monitoring of these resistances to avoid potential clinical and epidemiological consequences

    Genetic susceptibility to Andes Hantavirus: Association between severity of disease and HLA alleles in Chilean patients Susceptibilidad genética a hantavirus Andes: Asociación entre la expresión clínica de la infección y alelos del sistema HLA en paciente

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    Andes hantavirus (ANDV) infection in Chile has a variable clinical expression, and infected individuals may present with different grades of disease severity. This study aimed to determine if clinical expression of ANDV infection in Chilean patients is associated with the HLA system. HLA alleles A, B, DRB1 and DQB1, were studied in two groups of patients with confirmed ANDV infection: 41 patients with a mild disease course (without respiratory failure and cardiovascular shock) and 46 patients with a severe disease course (with respiratory failure and shock). Molecular typing of HLA system was performed by SSP-PCR. The HLA-DRB1*15 allele, was significantly more common in the group of patients with mild disease (p = 0,007) and thus for possibly associated with a protective effect against ANDV infection. Conversely, HLA-B*08 was more common in patients with severe disease (p = 0,06). Although the association was marginally significant, allele HLA-B*08 may be linked to an increased suscep

    La Atención a las Necesidades en Salud Mental de los Profesionales Sanitarios durante la COVID-19

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    Los profesionales sanitarios se encuentran en primera línea de atención a pacientes con COVID-19, presentando mayor riesgo de contagio y de afectación emocional. El objetivo del estudio es describir las necesidades en salud mental y conocer el efecto de una intervención psicológica en estos profesionales. Se incluyeron 47 trabajadores del Hospital Universitari Vall d’Hebron que solicitaron soporte psicológico durante el primer mes y medio de la crisis. Se administraron pre-post intervención un listado de síntomas clínicos, la Escala Clínica de Ansiedad y de Impresión Clínica Global. Consultaron mayoritariamente mujeres, profesionales de enfermería y técnicos auxiliares de enfermería, presentando hiperpreocupación, tristeza, alteraciones de sueño y orexia. Se observó una mejoría significativa en síntomas clínicos (z = 4.6, p ≤ .0001), estrés agudo (z = 2.5, p = .012), ansiedad (z = 5.3, p ≤ .0001) e impresión clínica (z = 4.1, p ≤ .0001). Una intervención psicológica breve, basada en técnicas de gestión de ansiedad, regulación emocional y orientación en valores reduce los síntomas emocionales en profesionales
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