Molecular diversity of the antimicrobial domain of beta-defensin 3 and homologous peptides

Human β-defensin 3 has received great interest for possible pharmaceutical applications. To characterize the biology of this antimicrobial peptide, the mouse β-defensin 14 has been selected as a prototypical model. This report provides definite evidence of true orthology between these defensins and reveals molecular diversity of a mammalian specific domain responsible for their antimicrobial activity. Specifically, this analysis demonstrates that eleven amino acid residues of the antimicrobial domain have been mutated by positive selection to confer protein niche specialization. These data support the notion that natural selection acts as evolutionary force driving the proliferation and diversification of defensins and introduce a novel strategy for the design of more effective antibiotics

Improving global influenza surveillance: trends of A(H5N1) virus in Africa and Asia

<p>Abstract</p> <p>Background</p> <p>Highly pathogenic avian influenza A(H5N1) viruses are an important health problem in many Asian and African countries. The current increase in human cases demonstrates that influenza A(H5N1) is still a significant global pandemic threat. Many health organizations have recognized the need for new strategies to improve influenza global surveillance. Specifically, the World Health Organization through the global technical consultation for influenza surveillance have called for a detailed picture of the current limitations, especially at the nation level, to evaluate, standardize and strength reporting systems. The main goal of our study is to demonstrate the value of genetic surveillance as part of a strategic surveillance plan. As a proof of concept, we evaluated the current situation of influenza A(H5N1) in Asian and Africa.</p> <p>Results</p> <p>Our analysis revealed a power-law distribution in the number of sequences of A(H5N1) viruses analyzed and/or reported to influenza surveillance networks. The majority of the Asian and African countries at great risk of A(H5N1) infections have very few (approximately three orders of magnitude) sequenced A(H5N1) viruses (e.g. hemagglutinin genes). This suggests that countries under pandemic alert for avian influenza A(H5N1) have very limited participation (e.g. data generation, genetic analysis and data share) in avian influenza A(H5N1) surveillance. More important, this study demonstrates the usefulness of influenza genetic surveillance to detect emerging pandemic threat viruses.</p> <p>Conclusions</p> <p>Our study reveals that some countries suffering from human cases of avian influenza have limited participation (e.g. genetic surveillance or data share) with global surveillance networks. Also, we demonstrate that the implementation of genetic surveillance programs could increase and strengthen worldwide epidemic and pandemic preparedness. We hope that this work promotes new discussions between policy makers and health surveillance organizations to improve current methodologies and regulations.</p

Impact of antigenic and genetic drift on the serologic surveillance of H5N2 avian influenza viruses

<p>Abstract</p> <p>Background</p> <p>Serologic surveillance of Avian Influenza (AI) viruses is carried out by the hemagglutination inhibition (HI) test using reference reagents. This method is recommended by animal health organizations as a standard test to detect antigenic differences (subtypes) between circulating influenza virus, vaccine- and/or reference- strains. However, significant discrepancies between reference antisera and field isolates have been observed during serosurveillance of influenza A viruses in pig and poultry farms. The objective of this study was to examine the effects of influenza virus genetic and antigenic drift on serologic testing using standard HI assays and reference reagents. Low pathogenic AI H5N2 viruses isolated in Mexico between 1994 and 2008 were used for phylogenetic analysis of AI hemagglutinin genes and for serologic testing using antisera produced with year-specific AI virus isolates.</p> <p>Results</p> <p>Phylogenetic analysis revealed significant divergence between early LPAI H5N2 viruses (1994 - 1998) and more recent virus field isolates (2002 - 2008). Results of the HI test were markedly influenced by the selection of the AI H5N2 virus (year of isolation) used as reference antigen for the assay. These analyses indicate that LPAI H5N2 viruses in Mexico are constantly undergoing genetic drift and that serosurveillance of AI viruses is significantly influenced by the antigen or antisera used for the HI test.</p> <p>Conclusions</p> <p>Reference viral antigens and/or antisera need to be replaced constantly during surveillance of AI viruses to keep pace with the AI antigenic drift. This strategy should improve the estimation of antigenic differences between circulating AI viruses and the selection of suitable vaccine strains.</p

Avian influenza: genetic evolution under vaccination pressure

Antigenic drift of avian influenza viruses (AIVs) has been observed in chickens after extended vaccination program, similar to those observed with human influenza viruses. To evaluate the evolutionary properties of endemic AIV under high vaccination pressure (around 2 billion doses used in the last 12 years), we performed a pilot phylogenic analysis of the hemagglutinin (HA) gene of AIVs isolated from 1994 to 2006. This study demonstrates that Mexican low pathogenicity (LP) H5N2-AIVs are constantly undergoing genetic drifts. Recent AIV isolates (2002–2006) show significant molecular drifts when compared with the H5N2 vaccine-strain or other field isolates (1994–2000). This study also demonstrates that molecular drifts in the HA gene lineages follow a yearly trend, suggesting gradually cumulative sequence mutations. These findings might explain the increasing incidence of LP H5N2 AIV isolated from commercial avian farms. These findings support recent concerns about the challenge of AIV antigenic drift and influenza epidemics

Method for Bacteriophage Delivery and Amplification

Methods of selecting wide host range bacteriophage capable of growing in a plurality of bacteria including pathogenic and non-pathogenic bacteria and bacteriophage selected are described. In addition to methods of treating a subject infected with a pathogenic bacterium using bacteriophage, of decontaminating objects using bacteriophage, of producing vaccines. In another aspect, methods of determining bacterial viability and methods of improving the sensitivity of a biosensor using wide host range bacteriophages are also disclosed

Method for bacteriophage delivery and amplification

Methods of selecting wide host range bacteriophage capable of growing in a plurality of bacteria including pathogenic and non-pathogenic bacteria and bacteriophage selected by the methods are disclosed. Also disclosed are: methods of treating a subject infected with a pathogenic bacterium using bacteriophage, of decontaminating objects using bacteriophage, and of producing vaccines. In another aspect, methods of determining bacterial viability and of improving the sensitivity of a biosensor using wide host range bacteriophages are also disclosed

On the Relationship between Sialomucin and Sulfomucin Expression and Hydrogenotrophic Microbes in the Human Colonic Mucosa

The colonic mucus layer is comprised primarily of acidomucins, which provide viscous properties and can be broadly classified into sialomucins or sulfomucins based on the presence of terminating sialic acid or sulfate groups. Differences in acidomucin chemotypes have been observed in diseases such as colorectal cancer and inflammatory bowel disease, and variation in sialo- and sulfomucin content may influence microbial colonization. For example, sulfate derived from sulfomucin degradation may promote the colonization of sulfate-reducing bacteria (SRB), which through sulfate respiration generate the genotoxic gas hydrogen sulfide. Here, paired biopsies from right colon, left colon, and rectum of 20 subjects undergoing routine screening colonoscopies were collected to enable parallel histochemical and microbiological studies. Goblet cell sialo- and sulfomucins in each biopsy were distinguished histochemically and quantified. Quantitative PCR and multivariate analyses were used to examine the abundance of hydrogenotrophic microbial groups and SRB genera relative to acidomucin profiles. Regional variation was observed in sialomucins and sulfomucins with the greatest abundance of each found in the rectum. Mucin composition did not appear to influence the abundance of SRB or other hydrogenotrophic microbiota but correlated with the composition of different SRB genera. A higher sulfomucin proportion correlated with higher quantities of Desulfobacter, Desulfobulbus and Desulfotomaculum, relative to the predominant Desulfovibrio genus. Thus, acidomucin composition may influence bacterial sulfate respiration in the human colon, which may in turn impact mucosal homeostasis. These results stress the need to consider mucus characteristics in the context of studies of the microbiome that target intestinal diseases

Salud de los trabajadores

Actividad f&iacute;sica y su relaci&oacute;n con los factores de riesgo cardiovascular de carteros chilenosAn&aacute;lisis de resultados: riesgos psicosociales en el trabajo Suceso-Istas 21 en Cesfam Quell&oacute;nAusentismo laboral por enfermedades oftalmol&oacute;gicas, Chile 2009Brote de diarreas por norovirus, posterremoto-tsunami, Constituci&oacute;n, Regi&oacute;n del MauleCalidad de vida en profesionales de la salud p&uacute;blica chilenaCaracterizaci&oacute;n del reposo laboral en personal del SSMN durante el primer semestre de 2010Concentraci&oacute;n de nicotina en pelo en trabajadores no fumadores expuestos a humo de tabaco ambientalCondiciones de trabajo y bienestar/malestar docente en profesores de ense&ntilde;anza media de SantiagoDisfunci&oacute;n auditiva inducida por exposici&oacute;n a xilenoErgonom&iacute;a aplicada al estudio del s&iacute;ndrome de dolor lumbar en el trabajoEstimaci&oacute;n de la frecuencia de factores de riesgo cardiovascular en trabajadores de una empresa mineraExposici&oacute;n a plaguicidas inhibidores de la acetilcolinesterasa en Colombia, 2006-2009Factores de riesgo y da&ntilde;os de salud en conductores de una empresa peruana de transporte terrestre, 2009Las consecuencias de la cultura en salud y seguridad ocupacional en una empresa mineraPercepci&oacute;n de cambios en la pr&aacute;ctica m&eacute;dica y estrategias de afrontamientoPercepci&oacute;n de la calidad de vida en la Universidad del Biob&iacute;oPesos m&aacute;ximos aceptables para tareas de levantamiento manual de carga en poblaci&oacute;n laboral femeninaRiesgo coronario en trabajadores mineros seg&uacute;n la funci&oacute;n de Framingham adaptada para la poblaci&oacute;n chilenaTrastornos emocionales y riesgo cardiovascular en trabajadores de la salu

Enfermedades crónicas

Adherencia al tratamiento farmacol&oacute;gico y relaci&oacute;n con el control metab&oacute;lico en pacientes con DM2Aluminio en pacientes con terapia de reemplazo renal cr&oacute;nico con hemodi&aacute;lisis en Bogot&aacute;, ColombiaAmputaci&oacute;n de extremidades inferiores: &iquest;est&aacute;n aumentando las tasas?Consumo de edulcorantes artificiales en j&oacute;venes universitariosC&oacute;mo crecen ni&ntilde;os normales de 2 a&ntilde;os que son sobrepeso a los 7 a&ntilde;osDiagn&oacute;stico con enfoque territorial de salud cardiovascular en la Regi&oacute;n MetropolitanaEfecto a corto plazo de una intervenci&oacute;n con ejercicio f&iacute;sico, en ni&ntilde;os con sobrepesoEfectos de la cirug&iacute;a bari&aacute;trica en pacientes con s&iacute;ndrome metab&oacute;lico e IMC &lt; 35 KG/M2Encuesta mundial de tabaquismo en estudiantes de profesiones de saludEnfermedades cr&oacute;nicas no transmisibles: Consecuencias sociales-sanitarias de comunidades rurales en ChileEpidemiolog&iacute;a de las muertes hospitalarias por patolog&iacute;as relacionadas a muerte encef&aacute;lica, Chile 2003-2007Estado nutricional y conductas alimentarias en adolescentes de 4&ordm; medio de la Regi&oacute;n de CoquimboEstudio de calidad de vida en una muestra del plan piloto para hepatitis CEvaluaci&oacute;n del proceso asistencial y de resultados de salud del GES de diabetes mellitus 2Factores de riesgo cardiovascular en poblaci&oacute;n universitaria de la Facsal, universidad de Tarapac&aacute;Implicancias psicosociales en la g&eacute;nesis, evoluci&oacute;n y tratamiento de pacientes con hipertensi&oacute;n arterial esencialInfarto agudo al miocardio (IAM): Realidad en el Hospital de Puerto Natales, 2009-2010Introducci&oacute;n de nuevas TIC y mejor&iacute;a de la asistencia a un programa de saludNi&ntilde;os obesos atendidos en el Cesfam de Puerto Natales y su entorno familiarPerfil de la mortalidad por c&aacute;ncer de cuello uterino en R&iacute;o de JaneiroPerfil del paciente primo-consultante del Programa de Salud Cardiovascular, Consultorio Cordillera Andina, Los AndesPrevalencia de automedicaci&oacute;n en mujeres beneficiarias del Hospital Comunitario de Til-TiPrevalencia de caries en poblaci&oacute;n preescolar y su relaci&oacute;n con malnutrici&oacute;n por excesoPrevalencia de retinopat&iacute;a diab&eacute;tica en comunas dependientes del Servicio de Salud Metropolitano Occidente (SSMOC)Problemas de adherencia farmacol&oacute;gica antihipertensiva en poblaci&oacute;n mapuche: Un estudio cualitativoRol biol&oacute;gico de los antioxidantes innatos en pacientes portadores de VIH/SidaSobrepeso en empleados de un restaurante de una universidad p&uacute;blica del estado de S&atilde;o Paul