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Sample records for bacterias sulfato-reductoras asociadas

  1. Bacterias halotolerantes/alcalofilas productoras de acido indol acético (aia) asociadas a arthrospira platensis (cyanophyceae)

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    Liliana Cecilia Gómez Gómez; Nelson Valero Valero; Ever Morales Avendaño

    2012-01-01

    Título en ingles: Halotolerant alkalophilic and indolacetic acid producing acid producing bacteria associated with Arthrospira platensis (Cyanophyceae) Resumen: Este trabajo tuvo como propósito contribuir al conocimiento de la interacción entre la cianobacteria alcalófila Arthrospira platensis y las bacterias que crecen asociadas a su mucilago. Se desarrolló un  medio de cultivo heterotrófico en el cual se aislaron cinco cepas bacterianas asociadas a un monocultivo de A. platensis. Se determi...

  2. PROMOCIÓN DEL CRECIMIENTO DE Baccharis macrantha (ASTERACEAE) CON BACTERIAS SOLUBILIZADORAS DE FOSFATOS ASOCIADAS A SU RIZOSFERA

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    Luz Marina LIZARAZO FORERO; Elsa Giovanna ÁVILA MARTÍNEZ; Francisco CORTÉS PÉREZ

    2015-01-01

    El objetivo de esta investigación fue aislar y caracterizar bacterias solubilizadoras de fosfatos (BSF) asociadas a la rizosfera de Baccharis macrantha y Viburnum triphyllum, y evaluar su capacidad para solubilizar fosfatos en condiciones in vitro. Además se determinó el efecto de la inoculaciónde las cepas de BSF más eficientes sobre el crecimiento de B. macrantha. Las muestras de suelo rizosférico de B. macrantha y V. triphyllum fueron colectadas en los meses de mayo-período de lluvia y sep...

  3. Bacterias halotolerantes/alcalofilas productoras de acido indol acético (AIA asociadas a Arthrospira platensis (Cyanophyceae

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    Liliana Cecilia Gómez Gómez

    2012-08-01

    Full Text Available Título en ingles: Halotolerant alkalophilic and indolacetic acid producing acid producing bacteria associated with Arthrospira platensis (Cyanophyceae Resumen: Este trabajo tuvo como propósito contribuir al conocimiento de la interacción entre la cianobacteria alcalófila Arthrospira platensis y las bacterias que crecen asociadas a su mucilago. Se desarrolló un  medio de cultivo heterotrófico en el cual se aislaron cinco cepas bacterianas asociadas a un monocultivo de A. platensis. Se determinó la capacidad de estas cinco cepas para producir ácido 3- indol acético (AIA. La tipificación molecular de los aislamientos bacterianos permitió identificarlos como Exiguobacterium aurantiacum str. DSM 20416, Xanthomonas sp. ML-122, Halomonas sp. Ap-5, Bacillus okhensis str.  Kh10-101, Indibacter alkaliphilus, type str. LW1T; todas las cepas bacterianas obtenidas  son halotolerantes, alcalófilas y productoras de AIA. Los resultados aportan evidencia para sugerir una interacción benéfica entre A. platensis y sus bacterias asociadas,  quizá como estrategia evolutiva  de cooperación para desarrollarse en  un ambiente hipersalino.    Palabras claves: Bacillus okhensis, Exiguobacterium aurantiacum, Halomonas sp., Indibacter alkaliphilus. Xanthomonas sp. Abstract: The aim of this study was contribute to knowledge over alkalophilic cianobacteryum  Arthrospira platensis  and their  interaction with some associated bacteria growing in their mucilage. Heterotrophic culture medium was designed, in this medium were isolated five bacterial strains associated to single culture of A. platensis. It was measured the 3-indol acetic acid (IAA production by these bacterial strains. Molecular typing allowed identify these bacterial strains like Exiguobacterium aurantiacum str. DSM 20416, Xanthomonas sp. ML-122, Halomonas sp. Ap-5, Bacillus okhensis str. Kh10-101, Indibacter alkaliphilus, type str. LW1T; all these bacteria are halotolerant

  4. PREVALENCIA DE BACTERIAS ASOCIADAS A LA INFERTILIDAD INFECCIOSA EN BOVINOS DE MONTERÍA, COLOMBIA

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    Marco González T

    2007-12-01

    Full Text Available Objetivo. Establecer la prevalencia de algunos gérmenes asociados con infertilidad infecciosa de bovinos del municipio de Montería. Materiales y métodos. Se recolectaron 384 muestras sanguíneas e igual número de hisopados cervicales de hembras que cumplieron con alguno de los siguientes criterios de inclusión: más de tres servicios sin concepción, vaginitis, cervicitis, metritis, endometritis, útero con contenido, momificación fetal, natimortos, reabsorciones embrionarias, antecedentes de abortos y/o hembras positivas a brucelosis. Las muestras cervicales se sembraron en agar Mc conkey, agar sangre, agar brucella y agar campylobacter. A las colonias sospechosas se le realizaron pruebas bioquímicas y la confirmación se llevó a cabo con pruebas serológicas. Para el serodiagnóstico de Brucella, los sueros fueron analizados por Rosa de Bengala y los positivos fueron confirmados con ELISA indirecta. Resultados. De las 384 muestras procesadas, hubo crecimiento en 281 (73,2%, las bacterias prevalentes fueron Escherichia coli, Bacilos Gram Negativos Oxidantes, Klepsiella spp y Pseudomonas spp, que correspondieron a 194 (69.1% aislamientos y cinco muestras equivalentes al 1.8% resultaron positivas para Campylobacter spp. Las pruebas serológicas para Brucella arrojaron como resultado 22 muestras positivas por ELISA (6.3%. Conclusiones. Los resultados de este trabajo describen de forma preliminar la posible asociación bacteriana en la infertilidad infecciosa en hembras vacunas, demostrando la presencia de una gran variedad de microorganismos.

  5. Presencia de bacterias asociadas a nieve marina en arrecifes influenciados por escorrentía continental del Caribe colombiano: primer acercamiento

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    Hernán Alejandro Henao-Castro; Elvira M. Alvarado Ch; Laura C. Rodríguez; Johanna Santamaría

    2015-01-01

    Parte del deterioro de los arrecifes de coral se atribuye al efecto del aporte de agua dulce cargada de nutrientes y sedimentos finos. Estas condiciones favorecen la formación de nieve marina lodosa que transporta gran carga de bacterias que pueden ser patógenos de corales. Por lo anterior, se estudió la presencia de bacterias asociadas a nieve marina lodosa en una zona arrecifal del Caribe colombiano en un gradiente de distancia a la desembocadura del canal del Dique (Cartagena). Por medio d...

  6. PROMOCIÓN DEL CRECIMIENTO DE Baccharis macrantha (ASTERACEAE CON BACTERIAS SOLUBILIZADORAS DE FOSFATOS ASOCIADAS A SU RIZOSFERA

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    Luz Marina LIZARAZO FORERO

    2015-07-01

    Full Text Available El objetivo de esta investigación fue aislar y caracterizar bacterias solubilizadoras de fosfatos (BSF asociadas a la rizosfera de Baccharis macrantha y Viburnum triphyllum, y evaluar su capacidad para solubilizar fosfatos en condiciones in vitro. Además se determinó el efecto de la inoculaciónde las cepas de BSF más eficientes sobre el crecimiento de B. macrantha. Las muestras de suelo rizosférico de B. macrantha y V. triphyllum fueron colectadas en los meses de mayo-período de lluvia y septiembre-período seco del 2012. Para la cuantificación de bacterias heterótrofas cultivables y BSF se empleó el método de recuento en placa en los medios Agar Tripticasa de Soya y Pikovskaya (PVK respectivamente. La capacidad de solubilización de fosfatos de las cepas aisladas se estimó a partir del diámetro de los halos formados alrededor de las colonias en el medio de cultivo PVK después de 7 días de incubación a 28 °C. Los ensayos de inoculación en B. macrantha se realizaron con las BSF más eficientes. La inoculación de las BSF B. firmus y P. fluorescens de forma individual y como inoculante combinado mostro un efecto benéfico, incrementando significativamente el porcentaje de germinación de semillas, la altura de la plántula, la longitud de la raíz y el peso seco de B. macrantha. La inoculación de BSF podría ser considerada una estrategia para mejorar el crecimiento y establecimiento de B. macrantha en pastizales abandonados.Growth Promotion of Baccharis macrantha (Asteraceae by Phosphate Solubilizing Rhizosphere Bacteria     The objectives of this research was to isolate and characterize phosphate solubilizing bacteria (BSF associated to the rhizosphere of Baccharis macrantha and Viburnum triphyllum, and to assess their ability to solubilize phosphate under conditions in vitro. Furthermore to determine the effect of inoculation of the strains BSF more efficient on the growth of B. macrantha. Rhizosphere soil samples of B

  7. DIVERSIDAD DE BACTERIAS ENDÓFITAS ASOCIADAS A RAÍCES DEL PASTO COLOSUANA (Bothriochloa pertusa EN TRES LOCALIDADES DEL DEPARTAMENTO DE SUCRE, COLOMBIA

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    FUENTES CUELLO JUSTO RAFAEL

    2010-08-01

    Full Text Available El objetivo del presente trabajo fue aislar diversidad de bacterias endófitas cultivables asociadas a raíces del pasto colosuana Bothriochloa pertusa (L A. Camus en tres localidades del departamento de Sucre, Colombia. La diversidad de bacterias endófitas fue realizada mediante el aislamiento de colonias en medios de cultivos. La densidad poblacional fue estimada por conteo directo de colonias en placa y las características culturales de cada morfotipo fueron obtenidas mediante observación de cada colonia formada. Se determinó la correlación diversidad, densidad poblacional y localidades, utilizando ANOVA y análisis de componentes principales o de correspondencia simple, mediante el programa estadístico R, 2009 (4,5. Fueron muestreadas 20 fincas por localidad; se observó presencia de diversos morfotipos de bacterias endófitas. Se encontró diferencias significativas entre diversidad (morfotipos, densidad poblacional (UFC.raíz-1 y localidades. La diversidad de bacterias endófitas representa apenas una pequeña fracción de la diversidad total existente en la naturaleza, siendo escasas las informaciones que se tienen de la presencia de estos microorganismos en agroecosistemas específicos, razón por lo cual este trabajo se convierte en la primera evidencia de asociación entre bacterias endófitas y raíces del pasto colosuana en Colombia. Palabras claves: Bacteria, endófitas, raíz, pasto

  8. Presencia de bacterias asociadas a nieve marina en arrecifes influenciados por escorrentía continental del Caribe colombiano: primer acercamiento

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    Hernán Alejandro Henao-Castro

    2015-06-01

    Full Text Available Parte del deterioro de los arrecifes de coral se atribuye al efecto del aporte de agua dulce cargada de nutrientes y sedimentos finos. Estas condiciones favorecen la formación de nieve marina lodosa que transporta gran carga de bacterias que pueden ser patógenos de corales. Por lo anterior, se estudió la presencia de bacterias asociadas a nieve marina lodosa en una zona arrecifal del Caribe colombiano en un gradiente de distancia a la desembocadura del canal del Dique (Cartagena. Por medio de técnicas moleculares PCR-DGGE, se registró baja riqueza, con bandas representativas de siete bacterias diferentes. El número de especies varió según el sitio, pero no hubo relación con la cercanía a la fuente de escorrentía. Como estudio pionero, sirve como punto de partida para estudios en arrecifes del Caribe colombiano impactados por escorrentía.

  9. Diversidad de las bacterias rizosféricas asociadas a plantas de Typha dominguesis en humedales del río Almendares

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    Irina Salgado-Bernal

    2012-01-01

    Full Text Available La gestión ambiental de los humedales es de interés actual, pero los estudios relacionados con los microor- ganismos asociados a las plantas de estos ecosistemas todavía son limitados. El objetivo del trabajo fue caracterizar la diversidad de grupos bacterianos presentes en la rizosfera de plantas hidrófitas de humedales naturales, en cuanto a su micromorfología y respuestas fisiológico - bioquímicas frente a compuestos químicos de interés ambiental. Se estudiaron 58 aislados bacterianos de la rizosfera de Typha dominguensis, en humedales del río Almendares, La Habana. Se carac- terizaron micromorfológica, tintorial y culturalmente y se analizó su interacción con diferentes fuentes de carbohidratos, nitrógeno, fósforo y metales pesados. Se detectó la representación de cinco grandes grupos bacterianos diferentes, debido a la diversidad de características micromorfológicas y tintoriales, con amplia variedad de características culturales. Los aislados presentaron comportamientos fisiológico -bioquímicos diversos. Fueron capaces de crecer con diferentes fuentes de carbono (glucosa, manosa, xilosa, lactosa y almidón; el 41 % las asimiló todas y el 76 % al menos tres. Se encontraron aislados que realizaron reducción del nitrato (47 % y amonificación (67 %; algunos (60 % con potencialidad para acu- mular fosfato y se observaron diferentes patrones de multirresistencia a los metales. Se estudiaron por primera vez en Cuba las bacterias rizosféricas asociadas a Typha dominguensis en humedales ribereños, como un elemento a valorar en las estrategias de conservación y como agentes con uso potencial en la biorremediación.

  10. “IDENTIFICACIÓN DE LA CORROSIÓN EN LOS ALAMBRES DE NIQUEL TITANIO Y ACERO INOXIDABLE Y LA PRESENCIA DE BACTERIAS ASOCIADAS EN UNA MUESTRA DE ARCOS UTILIZADOS EN PACIENTES DE LA CLÍNICA DE ORTODONCIA”.

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    Vargas Morales, Karla Odette

    2012-01-01

    El propósito de este trabajo de investigación fue identificar la presencia de corrosión en alambres de Níquel Titanio y Acero Inoxidable, así como presencia de bacterias asociadas en los mismos colocados en boca durante 4 meses en pacientes de la clínica de ortodoncia de la Universidad Michoacana de San Nicolás Hidalgo. En el tamaño de la muestra del presente estudio se utilizaron diez arcos: cinco de níquel titanio termoactivados y cinco de acero inoxidable. Los siguientes ...

  11. Ateroesclerosis asociada a infección por chlamydophila pneumoniae: interacción entre el ser humano y una bacteria

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    Alvaro Gudiño-Gomezjurado

    2015-04-01

    Full Text Available La ateroesclerosis y sus complicaciones constituyen una de las mayores causas de morbi-mortalidad a nivel mundial. Sin embargo, solo la mitad de los casos se justifica por los factores de riesgo tradicionales. No obstante, desde hace casi cinco décadas se ha intentado encontrar causas no tradicionales asociadas a la enfermedad ateroesclerótica. Varios agentes infecciosos han emergido como posibles candidatos centralizándose la investigación en Chlamydophila pneumoniae por su capacidad de infectar las células endoteliales durante el proceso ateroesclerótico. A lo largo del tiempo, múltiples estudios han tratado de probar la causalidad de C. pneumoniae en el proceso ateroesclerótico y sus complicaciones. A pesar de esto, hasta la fecha las conclusiones son ambiguas y de poca relevancia para la práctica clínica diaria.

  12. Bacterias asociadas a Salix atrocinerea y respuestas in vitro frente al estrés por As: potencial aplicación en fitorremediación

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    Navazas Álavrez, Alejandro

    2014-01-01

    La contaminación de suelos por arsénico es un grave problema ambiental que puede pasar a la cadena trófica y derivar en problemas de salud humana. Existe un reducido número de especies vegetales capaces de sobrevivir en estas zonas contaminadas y acumular concentraciones de metales pesados en sus tejidos muy superiores a las presentes en el suelo. Si además, también se tienen en cuenta las bacterias del suelo que movilicen metales, así como la caracterización e interacción planta-bacteria se ...

  13. Producción y formulación de prototipos de un biofertilizante a partir de bacterias nativas asociadas al cultivo de arroz (oryza sativa)

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    Johanna Rojas Sierra; Nubia Moreno-Sarmiento

    2009-01-01

    Los biofertilizantes son productos con base en microorganismos que están involucrados en los procesos nutritivos de las plantas. Además de los microorganismos, es necesario mejorar las condiciones de formulación de los productos para mantener la viabilidad y estabilidad en almacenamiento y campo. El objetivo de este trabajo fue evaluar formulaciones, las cuales se realizaron mezclando el ingrediente activo (bacteria fijadora de nitrógeno) en diferentes relaciones con sustancias húmicas, Polie...

  14. Producción y formulación de prototipos de un biofertilizante a partir de bacterias nativas asociadas al cultivo de arroz (Oryza sativa

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    Johanna Rojas Sierra

    2009-01-01

    Full Text Available Los biofertilizantes son productos con base en microorganismos que están involucrados en los procesos nutritivos de las plantas. Además de los microorganismos, es necesario mejorar las condiciones de formulación de los productos para mantener la viabilidad y estabilidad en almacenamiento y campo. El objetivo de este trabajo fue evaluar formulaciones, las cuales se realizaron mezclando el ingrediente activo (bacteria fijadora de nitrógeno en diferentes relaciones con sustancias húmicas, Polietilenglicol, Carbopol® y quelatos. Los prototipos que mantuvieron la viabilidad durante un periodo de aproximadamente tres meses se evaluaron en cultivos de arroz. Los formulados se evaluaron teniendo en cuenta la dosis aplicada (1 y 2 L/ha; el resultado de uno de los prototipos (M= 8500 kg/ha mostró un efecto benéfico sobre la producción superando a los testigos (7625 kg/ha. Los resultados de este trabajo, además de contribuir con el aumento de la estabilidad en almacenamiento de algunos prototipos, permitieron mostrar buenos resultados en campo (producción, ratificando la importancia que tienen estos microorganismos en los agroecosistemas. Palabras clave: biofertilizantes; formulación; nutrición vegetal; prototipos; sustancias húmicas; Biofertiliser; formulation; humic substance; plant nutrition; prototype.

  15. Caracterización molecular de la microbiota asociada al queso cotija

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    Barrera Chavez, Hugo

    2013-01-01

    El presente trabajo contempla la caracterización fenotípica y molecular de la microbiota asociada al proceso de elaboracion del queso cotija. Para esto, se obtuvieron 27 aislamientos pertenecientes a bacterias (16) y a levaduras (11).

  16. CARACTERIZACIÓN DE BACTERIAS DIAZOTRÓFICAS ASIMBIÓTICAS ASOCIADAS AL EUCALIPTO (Eucalyptussp. EN CODAZZI, CESAR (COLOMBIA Characterization of Diazotrophic Bacteria Non-Symbiotic Associated with Eucalyptus (Eucalyptussp. in Codazzi, Cesar (Colombia

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    DOLLY MELISSA OBANDO CASTELLANOS

    .05 in the population with respect to the climate epoch, suggesting that these bacteria are able to tolerate stress conditions by different physiological mechanisms. With respect to the stratum sample isolates attempts of Herbaspirillum sp. and Azospirillum sp. significant differences in rhizospheric soil and roots. We obtained 44 isolates of which were grouped by phenotypic characterization as 14 suspected of Beijerinckia sp., 12 Azotobacter sp., 8 Derxia sp., 4 Herbaspirillum sp., 5 Azospirillum sp., 1 Gluconacetobacter sp. and 1 Burkholderia sp. Due to their high potential were selected isolates C27, C26 and C25. These four strains present the best values of efficiency in vitro, exceeding production values of the reference strains used (A. chroococcum (AC1 and A. brasilense (SP7.

  17. Study of sulphate-reducing bacteria corrosion in the weld joint for API X-70 steel

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    Flores, J. E.

    2012-10-01

    Full Text Available The corrosion behavior originated by sulfate-reducing bacteria (SRB was studied in two regions of welded API X-70 steel pipeline. The studies were focused on base material (BM and heat affected zone (HAZ, from the internal region of the pipe. SRB were extracted from oil and grown in a Postgate medium. Corrosion was evaluated at 60 °C for times between 5 and 64 days. Potentiodynamic polarization curves, obtained by electrochemical techniques, indicated surface activation at short times. Structural and morphological characterizations were carried out by scanning electron microscopy (SEM and optical microscopy (OM. H2S concentration and pH were also measured. Results showed an important increase in the corrosion damage up to 20 days, influenced by the SRB activity, which lead to a maximum of H2S (pH minimum. It was found a localized corrosion attack in the HAZ in a higher quantity compared to BM; and the formation of a thin film on the steel surface, originated by corrosion products and bacterial activity.

    El comportamiento ante la corrosión, originada por bacterias sulfato-reductoras (SRB, fue estudiado en dos regiones de un tubo de acero soldado API X-70. Los estudios se enfocaron en el material base (BM y la zona afectada térmicamente (HAZ, en la parte interna del tubo. Las SRB fueron extraídas del petróleo y cultivadas en un medio Postgate. El comportamiento a la corrosión fue evaluado a una temperatura de 60 °C, por periodos comprendidos entre 5 y 64 días. El análisis de las curvas de polarización potenciodinámicas, obtenidas por técnicas electroquímicas, indicó la activación de la superficie para tiempos cortos. La superficie fue caracterizada estructural y morfológicamente mediante microscopia electrónica de barrido (SEM, así como mediante microscopía óptica (OM. La concentración de H2S y el pH también fueron medidos. Los resultados mostraron un aumento importante de la corrosi

  18. Hemicorea asociada a toxoplasmosis cerebral y SIDA

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    N.S. garretto

    1995-03-01

    Full Text Available Se observan complicaciones neurológicas en 40% de enfermos con SIDA. De estos, en 10% puede ser la manifestation inicial de la enfermedad. En otro 11% pueden aparecer trastornos del movimiento. Comunicamos el primer caso de hemicorea asociada a toxoplasmosis cerebral y SIDA en nuestro pais. Hombre de 26 anos, con diagnostico de SIDA y toxoplasmosis cerebral. Habia comenzado con crisis motoras simples de hemicuerpo izquierdo, con generalization secundaria y luego perdida de fuerza progresiva en dicho hemicuerpo. La RMN de cérebro mostro una lesion frontal derecha y otra temporo-occipital izquierda, con gran edema perilesional y efecto de masa. Las serologias para HIV y toxoplasmosis fueron positivas. Comenzo tratamiento con sulfadiazina y pirimetamina. Al duodecimo dia aparecieron movimientos involuntários dei pie izquierdo, coreicos, que se extendieron mas tarde a todo ese miembro inferior y luego al hemicuerpo. Nueva RMN de cérebro mostro disminucion dei edema y efecto de masa de las lesiones. Sin embargo, se observo una nueva lesion a nivel peduncular derecho. Movimientos involuntarios en pacientes con toxoplasmosis cerebral comenzaron a describirse recientemente solo en pacientes con SIDA. El presente seria el decimotercer caso de la literatura mundial y el primero en nuestro pais de hemicorea asociada a toxoplasmosis y SIDA.

  19. IDENTIFICACIÓN MOLECULAR DE POBLACIONES BACTERIANAS ASOCIADAS AL CARACOL PALA (Strombus gigas DEL CARIBE COLOMBIANO

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    ROMERO MAGALLY

    2009-08-01

    Full Text Available RESUMEN

    El caracol Pala, Strombus gigas (Strombidae, es de gran importancia ecológica y socioeconómica en el área caribeña colombiana. Sin embargo, es una especie catalogada como “vulnerable” y existe muy poca información referente a las especies bacterianas asociadas al caracol que puedan ser importantes para el desarrollo, manejo productivo y de seguridad acuícola de estos gastrópodos. En este trabajo, nosotros empleamos un estudio microbiológico y molecular de la región intergénica entre los genes 16S y 23S rDNA, análisis del gen rDNA 16S y secuenciación, para analizar las bacterias asociadas al caracol Pala (S. gigas. La composición de bacterias cultivables asociadas fue evaluada por su capacidad para crecer en agar marino y en medios de cultivos selectivos. De un total de 28 muestras analizadas encontramos que el número de bacterias cultivadas en condiciones aerobias fue de alrededor 106 ufc mL-1 donde las bacterias pertenecientes a la familia Vibrionacea fueron las más abundantes, cerca de >105 ufc mL-1 . El análisis molecular de la región intergénica entre los genes 16S y 23S rDNA de las diferentes muestras, reveló una gran complejidad bacteriana asociada a S. gigas. Las secuencias de los amplificados del gen rDNA 16S identificó Pseudoalteromonas sp., Halomonas sp., Psycrobacter sp., Cobetia sp., Pseudomonas sp. y Vibrios sp. Nuestros resultados podrían sugerir un rol importante de estas bacterias como componentes de la comunidad asociada al S. gigas. Esta información puede complementar los estudios que se están implementando en los procesos para la conservación y repoblamiento de las poblaciones de S. gigas en Colombia.

    Palabras clave: Strombus gigas, Caracol pala, Bacteria, Región intergénica 16S-23S, rDNA 16S.

    ABSTRACT

    The Queen Conch, Strombus gigas (Strombidae, is a species of great ecological and socioeconomic importance in the Caribbean area of Colombia

  20. Epidemia de neumonía asociada a ventilación mecánica en Mérida, Yucatán

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    Zaidi Mussaret

    1999-01-01

    Full Text Available OBJETIVO. Determinar las principales características epidemiológicas, clínicas y microbiológicas de una epidemia de neumonía asociada a ventilación mecánica en una unidad de cuidados intensivos en Mérida, Yucatán. MATERIAL Y MÉTODOS. Se diseñó un estudio prospectivo y observacional de 11 meses para determinar incidencia, mortalidad, reservorios potenciales, agentes etiológicos y sus patrones de sensibilidad antimicrobiana. RESULTADOS. La incidencia de neumonía asociada a ventilador fue de 74%. La mortalidad cruda fue de 88%, comparada con una mortalidad esperada de 19.5%. Se aislaron bacterias gramnegativas en 98% de los cultivos, de las cuales 46% fueron sensibles a cefalosporinas de tercera generación, 59% a cefalosporinas de cuarta generación, 70% a ciprofloxacina y 100% a imipenem. Se aislaron Klebsiella pneumoniae y Pseudomonas aeruginosa de algunos circuitos del ventilador y el lavado. CONCLUSIONES. La elevada incidencia de neumonía y la mortalidad asociada en esta unidad de cuidados intensivos se pueden atribuir a la falta de medidas de control de infecciones y a una elevada prevalencia de gérmenes multirresistentes que se relaciona con el uso desmesurado e irracional de antibióticos.

  1. Oclusión arterial aguda asociada a hidatidosis diseminada

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    Jose Somocurcio

    2014-06-01

    Full Text Available Hidatidosis o equinococosis son términos usados para denominar a la infestación zoonótica causada por los estadios adulto y larvario (metacéstode del céstode del género Equinococcus (familia tenidae. El término hidatidosis debe ser aplicado a la infestación por el metacéstode mientras que el de equinococosis a los estadios larvario y adulto. En el Perú existe una alta prevalencia de esta infección siendo el hígado y pulmón los órganos más afectados. Existen factores tanto del agente infeccioso como del hospedero que contribuyen a esta infección, donde el componente inmunológico del hospedero es un punto importante tanto en la infección como en la diseminación. En el presente artículo se reporta un caso de oclusión arterial aguda asociada a hidatidosis diseminada en un paciente de 54 años de edad, natural y procedente de Huancavelica, de inicio súbito con un cuadro de obstrucción arterial aguda; que no mejoró luego de la cirugía con fallecimiento a las 48 horas de la presentación

  2. Oclusión arterial aguda asociada a hidatidosis diseminada

    Directory of Open Access Journals (Sweden)

    Jose Somocurcio

    2014-04-01

    Full Text Available Hidatidosis o equinococosis son términos usados para denominar a la infestación zoonótica causada por los estadios adulto y larvario (metacéstode del céstode del género Equinococcus (familia tenidae. El término hidatidosis debe ser aplicado a la infestación por el metacéstode mientras que el de equinococosis a los estadios larvario y adulto. En el Perú existe una alta prevalencia de esta infección siendo el hígado y pulmón los órganos más afectados. Existen factores tanto del agente infeccioso como del hospedero que contribuyen a esta infección, donde el componente inmunológico del hospedero es un punto importante tanto en la infección como en la diseminación. En el presente artículo se reporta un caso de oclusión arterial aguda asociada a hidatidosis diseminada en un paciente de 54 años de edad, natural y procedente de Huancavelica, de inicio súbito con un cuadro de obstrucción arterial aguda; que no mejoró luego de la cirugía con fallecimiento a las 48 horas de la presentación

  3. Proteínas asociadas a los componentes del citoesqueleto

    Directory of Open Access Journals (Sweden)

    Delia Mercedes Rojo Domínguez

    2004-01-01

    Full Text Available El citoesqueleto es una compleja trama de filamentos en el citoplasma que sirve como "huesos y musculos" de las células eucariotas y que permite las propiedades de forma, organización interna y movimiento. Los filamentos que constituyen el citoesqueleto son: los microtúbulos, los filamentos intermedios y los filamentos de actina de 24,10 y 7 nm de diámetro respectivamente. Los principales avances logrados en el conocimiento de esta dinámica estructura subcelular derivan de estudios realizados en músculos y tejidos cuyas células presentan cilios o flagelos, las cuales poseen funciones evidentemente asociadas al movimiento mecánico. Los componentes moleculares presentes en estas estructuras están también en aquellas que conforman el citoesqueleto de todas las células. Los filamentos y microtúbulos que participan en los movimientos del músculo y de los cilios presentan propiedades muy semejantes a las observadas en el citoesqueleto, pero difieren en estabilidad. Los movimientos del citoesqueleto son muy lábiles y cambiantes mientras que los del músculo y los de los cilios son más estables. Los dos tipos más importantes de filamentos del citoesqueleto son los de actina y los microtúbulos. Ambos están formados por subunidades de proteínas que pueden ensamblarse y desensamblarse rápidamente en las células. Existen delicados mecanismos que controlan este ensamble del pool de subunidades no polimerizadas en el citoplasma. Los filamentos intermedios se encuentran en la mayor parte de las células animales. Están formados por subunidades de proteí- nas fibrosas y son mucho más estables que la mayoría de los filamentos de actina y los microtúbulos.

  4. Neumonía asociada al cuidado de la salud

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    Adrián Ceccato

    2014-02-01

    Full Text Available La neumonía asociada al cuidado de la salud (NACS es una entidad diferente a la neumonía adquirida en la comunidad y a la neumonía intrahospitalaria. Existen circunstancias de riesgo para su desarrollo, se describen diferentes formas de presentación, gravedad y patógenos; y hay desacuerdo sobre el tratamiento empírico inicial. El objetivo de este estudio fue analizar la etiología, las características clínicas y la evolución de la NACS en un hospital general. Estudio prospectivo observacional con 60 pacientes; 32 con internación previa en los últimos 90 días, 9 en hemodiálisis, 12 residentes en hogares asistenciales y 7 en tratamiento en un hospital de día. El promedio de edad fue de 63 años; los índices de gravedad al ingreso fueron elevados. Las comorbilidades más frecuentes fueron las cardiológicas. El compromiso radiológico abarcó más de un lóbulo en el 42% de los casos y un 18% mostró derrame pleural. Se aisló el germen patógeno en 18 pacientes (30%; Streptococcus pneumoniae fue el más aislado (9 casos. Solo hubo un caso de multirresistencia. La estadía hospitalaria promedio fue de 11 días; 6 pacientes presentaron complicaciones, y la mortalidad fue del 5%. Las complicaciones, aunque no la mortalidad, fueron significativamente mayores en el grupo en diálisis (valor de p: 0.011 y 0.056, respectivamente. Los cuadros fueron graves pero la mortalidad fue baja. La resistencia antibiótica hallada no justifica un cambio en el esquema antibiótico usado habitualmente en las neumonías de la comunidad.

  5. Luxación posterior de codo asociada a traslocación radiocubital proximal

    OpenAIRE

    Gascó Gómez, J.; Gomar Sancho, Francisco; Gascó Adrién, J.

    2004-01-01

    La luxación de codo en los niños es poco frecuente y normalmente suele ir asociada a fracturas. La luxación asociada a traslocación radiocubital proximal es excepcional y tan sólo nueve casos se han publicado. Se presenta el caso de un niño de 9 años que tras una caída casual presentó luxación de codo asociada a traslocación radiocubital. Esta lesión fue descrita por primera vez por MacSween en 1978. El mecanismo de producción más frecuente pude ser una caída sobre la mano y antebrazo en p...

  6. Enfermedad pulmonar difusa asociada al consumo de tabaco Smoking related interstitial lung disease. Case report

    OpenAIRE

    JORGE YÁNEZ V; SERGIO GONZÁLEZ B; FERNANDO SALDÍAS P

    2008-01-01

    la enfermedad pulmonar difusa asociada al consumo de tabaco no ha sido claramente definida, la bronquiolitis respiratoria (RB) es un hallazgo morfológico frecuente en fumadores asintomáticos, se caracteriza por la acumulación de macrófagos pigmentados en los bronquiolos respiratorios. Sólo una pequeña proporción de los sujetos fumadores presenta una respuesta inflamatoria exagerada que compromete el intersticio y espacio alveolar, lo cual corresponde a la bronquiolitis respiratoria asociada a...

  7. Diversidad de levaduras asociadas a chichas tradicionales de Colombia

    Directory of Open Access Journals (Sweden)

    William Andrés López-Arboleda

    2011-01-01

    Full Text Available Título en inglés: Yeast diversity associated to Colombian traditional “chichas” Resumen En Colombia el conocimiento de la comunidad levaduriforme ha sido limitado, ya que los estudios se han enfocado principalmente en especies de interés clínico. Las fermentaciones espontáneas a partir de diversos sustratos representan hábitats de gran importancia para el estudio de la dinámica de las poblaciones de levaduras nativas, por esta razón, en el presente estudio se aislaron e identificaron las levaduras asociadas a las chichas de maíz, piña y arracacha, que son bebidas fermentadas de manera artesanal en Colombia. Se realizó el aislamiento de las levaduras más representativas de la chicha durante sus tres fases de fermentación: inicial, tumultuosa y final. Inicialmente, se hizo una caracterización parcial de los aislados, que incluyó pruebas fisiológicas, y medición de su capacidad para producir filamentos y esporas. Sin embargo, debido a que estas técnicas no fueron suficientes para identificar los aislados hasta el nivel taxonómico de género o de especie, se complementó el estudio de cada aislado empleando técnicas moleculares basadas en el análisis de restricción del gen rRNA 5.8S y los espaciadores transcritos internos (ITS1 e ITS2. Cuando el empleo de esta técnica no permitió obtener resultados definitivos y para confirmar las asignaciones realizadas usando PCR-RFLPs, se secuenció el dominio D1/D2 del gen 26S rRNA de los aislados más representativos. Mediante estas técnicas se lograron identificar las especies más representativas de los tres tipos de chicha: Candida tropicalis, Pichia kluyveri, Pichia guilliermondii, Hanseniapora guilliermondii, Pichia fermentans, Saccharomyces cerevisiae, Candida maltosa, Rhodotorula glutinis, Torulaspora delbrueckii, Hanseniaspora uvarum, Kazachstania exigua, Kluyveromyces marxianus, Yarrowia lypolitica, Candida parapsilosis, Debaromyces hansenii, Cryptococcus arboriformis

  8. IDENTIFICACIÓN MOLECULAR DE POBLACIONES BACTERIANAS ASOCIADAS AL CARACOL PALA (Strombus gigas DEL CARIBE COLOMBIANO Molecular Identification Of Bacterial Populations Associated To Queen Conch (Strombus gigas From Colombian Caribbe

    Directory of Open Access Journals (Sweden)

    EDINSON ANDRÉS ACOSTA

    Full Text Available El caracol Pala, Strombus gigas (Strombidae, es de gran importancia ecológica y socioeconómica en el área caribeña colombiana. Sin embargo, es una especie catalogada como "vulnerable" y existe muy poca información referente a las especies bacterianas asociadas al caracol que puedan ser importantes para el desarrollo, manejo productivo y de seguridad acuícola de estos gastrópodos. En este trabajo, nosotros empleamos un estudio microbiológico y molecular de la región intergénica entre los genes 16S y 23S rDNA, análisis del gen rDNA 16S y secuenciación, para analizar las bacterias asociadas al caracol Pala (S. gigas. La composición de bacterias cultivables asociadas fue evaluada por su capacidad para crecer en agar marino y en medios de cultivos selectivos. De un total de 28 muestras analizadas encontramos que el número de bacterias cultivadas en condiciones aerobias fue de alrededor 10(6 ufc mL-1 donde las bacterias pertenecientes a la familia Vibrionacea fueron las más abundantes, cerca de >10(5 ufc mL-1. El análisis molecular de la región intergénica entre los genes 16S y 23S rDNA de las diferentes muestras, reveló una gran complejidad bacteriana asociada a S. gigas. Las secuencias de los amplificados del gen rDNA 16S identificó Pseudoalteromonas sp., Halomonas sp., Psycrobacter sp., Cobetia sp., Pseudomonas sp. y Vibrios sp. Nuestros resultados podrían sugerir un rol importante de estas bacterias como componentes de la comunidad asociada al S. gigas. Esta información puede complementar los estudios que se están implementando en los procesos para la conservación y repoblamiento de las poblaciones de S. gigas en Colombia.The Queen Conch, Strombus gigas (Strombidae, is a species of great ecological and socioeconomic importance in the Caribbean area of Colombia. However, it is currently catalogued as "vulnerable"; there is limited information concerning the bacterial species associated with conch and important in the

  9. Relacionando las distribuciones binomial negativa y logarítmica vía sus series asociadas

    OpenAIRE

    Sadinle, Mauricio

    2011-01-01

    La distribución binomial negativa está asociada a la serie obtenida de derivar la serie logarítmica. Recíprocamente, la distribución logarítmica está asociada a la serie obtenida de integrar la serie asociada a la distribución binomial negativa. El parámetro del número de fallas de la distribución Binomial negativa es el número de derivadas necesarias para obtener la serie binomial negativa de la serie logarítmica. El razonamiento presentado puede emplearse como un método alternativo para pro...

  10. Calcificación vascular asociada a inflamación : influencia de la vitamina D

    OpenAIRE

    Guerrero Pavón, Fátima

    2012-01-01

    Arteriosclerosis y aterosclerosis son procesos comunes en los pacientes con enfermedad renal crónica (ERC). De hecho, la calcificación vascular (CV) representa un importante factor de riesgo que contribuye a la alta tasa de mortalidad cardiovascular asociada a la ERC. En pacientes urémicos, la CV está causada, en parte, por alteraciones en el metabolismo mineral estrechamente relacionadas con el control del hiperparatiroidismo secundario (HPT2º). Los pacientes con ERC muestr...

  11. Lesiones cutáneas asociadas a leucemia Infantil: Presentación de dos casos

    Directory of Open Access Journals (Sweden)

    Alejandra Acosta-Gualandri

    2011-01-01

    Full Text Available La leucemia cutánea es una patología extremadamente infrecuente y se puede presentar en diferentes tipos de leucemias, asociada o no a síndromes genéticos. Es una forma muy poco común de presentación inicial de malignidad, por lo que es importante reportar dos casos atendidos en el HNN.

  12. Incertidumbre asociada con el balance hídrico de largo plazo

    OpenAIRE

    Álvarez Villa, Oscar David; Vélez Upegui, Jaime Ignacio; Poveda Jaramillo, Germán

    2008-01-01

    Se calculan los balances hídricos de largo plazo para algunas cuencas instrumentadas en Colombia y se ha cuantificado la incertidumbre asociada que se propaga desde los campos de entrada al balance de largo plazo, precipitación y evapotranspiración. Además tambien se cuantifica la incertidumbre generada en la medición del área de la cuenca empleando un Modelo Digital de Elevaciones, MDE.

  13. Endocarditis infecciosa asociada con dispositivos electrónicos implantables intracardíacos. Nuestra experiencia

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    Fabián Salmo

    2007-01-01

    Full Text Available IntroducciónLa endocarditis infecciosa es una patología con una morbimortalidad elevada. En esta comunicación se presentan 17 casos de endocarditis infecciosa (EI asociada con dispositivos electrónicos implantables (DEI, que representaron el 6% de las endocarditis entre 1992 y 2005.ObjetivoAnalizar las características clínicas, evolutivas y anatomopatológicas de un subgrupo de pacientes con EI portadores de DEI.Material y métodosDe un total de 263 pacientes con EI admitidos en nuestra institución entre 1992 y 2005, se analizaron 17 con EI asociada con DEI.Las EI asociadas con DEI se clasificaron en: 1 temprana, la ocurrida dentro de los 12 meses del posquirúrgico, y 2 tardía, la producida luego de ese lapso. En todos los pacientes se obtuvieron muestras para hemocultivos, se efectuó el cultivo de todo material extraído durante la cirugía y se realizaron ecocardiogramas por vía transtorácica (ETT y transesofágica (ETE.ResultadosDe los 17 pacientes, 13 (73% eran hombres; la edad promedio fue de 60 años y el tiempo entre el implante y el diagnóstico fue de 344 días. Dieciséis pacientes presentaron fiebre y bacteriemia; el germen predominante fue Staphylococcus aureus en el 70% de los casos. En todos se extrajo el sistema. La mortalidad fue del 17%.ConclusionesLa EI asociada con el DEI, que debe sospecharse siempre en ausencia de otro foco infeccioso, constituye un subgrupo que con diagnóstico y tratamiento precoz tiene una mortalidad menor que la global descripta. Al igual que para la EI sin DEI, los hemocultivos y la ecocardiografía son los pilares para el diagnóstico.

  14. Methanotrophic bacteria.

    OpenAIRE

    Hanson, R S; Hanson, T. E.

    1996-01-01

    Methane-utilizing bacteria (methanotrophs) are a diverse group of gram-negative bacteria that are related to other members of the Proteobacteria. These bacteria are classified into three groups based on the pathways used for assimilation of formaldehyde, the major source of cell carbon, and other physiological and morphological features. The type I and type X methanotrophs are found within the gamma subdivision of the Proteobacteria and employ the ribulose monophosphate pathway for formaldehy...

  15. CARACTERIZACIÓN DE BACTERIAS DIAZOTRÓFICAS ASIMBIÓTICAS ASOCIADAS AL EUCALIPTO (Eucalyptus sp. EN CODAZZI, CESAR.

    Directory of Open Access Journals (Sweden)

    Divan Baldani Vera Lúcia

    2010-12-01

    Full Text Available Se evaluó el efecto de las épocas climáticas (lluvia y sequía y del estrato de la muestra (Suelo rizosférico, raíces y hojas sobre la población de los géneros Azotobacter, Beijerinckia, Derxia, Azospirillum, Herbaspirillum, Gluconacetobacter y Burkholderia en el Eucalipto (Eucalyptus sp.. Así mismo, se evalúo su capacidad en la producción de compuestos indólicos como promotores del crecimiento vegetal y su actividad de reducción de acetileno como indicador de la fijación biológica de nitrógeno. Los resultados no registraron diferencias estadísticas significativas en el test de Tukey (P ≤ 0.05 en la población con respecto a la época climática. Con respecto al estrato de muestra, los aislamientos tentativos a Herbaspirillum sp. y Azospirillum sp. presentaron diferencias significativas en suelo rizosférico y raíces. Se obtuvieron 44 aislamientos de los cuales se agruparon por caracterización fenotípica como: 14 presuntivos del género Beijerinckia sp., 12 de Azotobacter sp., 8 de Derxia sp., 4 de Herbarpirillum sp., 5 de Azospirillum sp., 1 de Gluconacetobacter sp. y 1 de Burkholderia sp. Por su alto potencial fueron seleccionados y criopreservados los aislamientos C27, C26, C25 y C45, las cuales presentaron los mejores valores de eficiencia in vitro, superando valores de producción de las cepas de referencia utilizadas (A. chroococcum (AC-01 y A. brasilense (SP7.

  16. Funciones ejecutivas y sintomatología asociada con los trastornos de la conducta alimentaria

    OpenAIRE

    Nayelli Alvarado Sánchez; Cecilia Silva Gutiérrez

    2014-01-01

    Estudios recientes coinciden en que las pacientes con trastornos de la conducta alimentaria (TCA) presentan ineficiencias en las funciones ejecutivas secundarias al padecimiento. Así, el objetivo de este trabajo fue explorar la posibilidad de que tales ineficiencias formen parte del endofenotipo de los TCA y que no sean únicamente consecuencias de los mismos. Para ello, se evaluaron 69 mujeres: 23 con TCA, 23 con sintomatología asociada a los TCA y 23 sin sintomatología de riesgo a desarrolla...

  17. Tiroidectomía asociada a paratiroidectomía por hiperparatiroidismo primario y secundario

    OpenAIRE

    Pardal Refoyo, José Luis; Santiago Peña, Luis Francisco

    2014-01-01

    [ES] Introducción: La asociación de patología tiroidea y paratiroidea es frecuente y puede dificultar el diagnóstico preoperatorio por lo que debe hacerse estudio tiroideo funcional y estructural en el hiperparatiroidismo. Objetivo: Conocer la incidencia de patología quirúrgica de paratiroides y tiroides asociadas. Material y método: Estudio histórico de casos y control en 105 pacientes sometidos a paratiroidectomía total o parcial por hiperparatiroidismo primario (83,81%) o secundario (16...

  18. Biomarcadores del estado inflamatorio: nexo de unión con la obesidad y complicaciones asociadas

    OpenAIRE

    Zulet, M A; B. Puchau; Navarro, C; Marti, A.; J. A. Martinez

    2007-01-01

    El objetivo de este trabajo ha consistido en realizar una revisión de los biomarcadores que actualmente se proponen como el nexo de unión entre la inflamación, la obesidad y complicaciones asociadas, seleccionando los estudios llevados a cabo y las cuestiones pendientes. Cada vez hay mayor evidencia científica de que la inflamación puede jugar un papel importante en la etiología de diversas enfermedades crónicas de gran relevancia para la salud pública. En los últimos ...

  19. Infección Nosocomial Asociada a los Catéteres Centrales

    OpenAIRE

    Rebollo Garrido, Sara

    2015-01-01

    La utilización de catéteres centrales es una de las técnicas que con más frecuencia se realizan en las unidades de cuidados intensivos, actualmente también ha aumentado en la asistencia hospitalaria. En la implantación y manejo del catéter central se necesita personal cualificado para evitar las complicaciones asociadas a estos. Es una técnica compleja que puede llegar a producir diversas complicaciones. Los sistemas intravenosos como son los catéteres centrales contribuyen a q...

  20. Poliartritis asociada a hepatozoonosis canina: descripción de un caso

    OpenAIRE

    Iveli, Sebastián; Casas, Luciano; Machuca, Mariana; Eiras, Diego Fernando; del Amo, Alicia

    2015-01-01

    El objetivo de este trabajo fue describir un caso de poliartritis asociada a Hepatozoon canis en un canino, mestizo, macho, de 5 meses de edad. El paciente presentaba fiebre (40,1 ºC), mucosas pálidas, linfonódulos superficiales ligeramente aumentados de tamaño, dolor lumbar, aumento de tamaño de varias articulaciones y abundantes garrapatas (Rhipicephalus sanguineous). En los extendidos sanguíneos se constató la presencia de gamontes de Hepatozoon sp. en el citoplasma de los neutrófilos. El ...

  1. Funciones ejecutivas y sintomatología asociada con los trastornos de la conducta alimentaria

    Directory of Open Access Journals (Sweden)

    Nayelli Alvarado Sánchez

    2014-01-01

    Full Text Available Estudios recientes coinciden en que las pacientes con trastornos de la conducta alimentaria (TCA presentan ineficiencias en las funciones ejecutivas secundarias al padecimiento. Así, el objetivo de este trabajo fue explorar la posibilidad de que tales ineficiencias formen parte del endofenotipo de los TCA y que no sean únicamente consecuencias de los mismos. Para ello, se evaluaron 69 mujeres: 23 con TCA, 23 con sintomatología asociada a los TCA y 23 sin sintomatología de riesgo a desarrollarlas. Todas las participantes respondieron el cuestionario de actitudes hacia la alimentación, la entrevista diagnóstica de trastornos alimentarios-IV, la Torre de Londres y la prueba de clasificación de tarjetas de Wisconsin. Los resultados mostraron ineficiencias en las funciones ejecutivas, específicamente en la planeación y en la flexibilidad de pensamiento, en el grupo con sintomatología asociada a los TCA similares a las que presentaron las participantes con TCA; hallazgos que abren la posibilidad de que las dificultades sean previas al establecimiento y que incluso pudiesen constituirse como un factor de riesgo.

  2. Anaerobic bacteria

    Science.gov (United States)

    Brook I, Goldstein EJ. Diseases caused by non-spore forming anaerobic bacteria. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 297. Stedman's Online ...

  3. Enfermedad pulmonar difusa asociada al consumo de tabaco Smoking related interstitial lung disease. Case report

    Directory of Open Access Journals (Sweden)

    JORGE YÁNEZ V

    2008-03-01

    Full Text Available la enfermedad pulmonar difusa asociada al consumo de tabaco no ha sido claramente definida, la bronquiolitis respiratoria (RB es un hallazgo morfológico frecuente en fumadores asintomáticos, se caracteriza por la acumulación de macrófagos pigmentados en los bronquiolos respiratorios. Sólo una pequeña proporción de los sujetos fumadores presenta una respuesta inflamatoria exagerada que compromete el intersticio y espacio alveolar, lo cual corresponde a la bronquiolitis respiratoria asociada a enfermedad pulmonar difusa (RBIID, que se manifiesta por disnea de esfuerzos y tos. la neumonía intersticial descamativa (DIP se caracteriza por compromiso panlobular, fibrosis intersticial discreta e infiltración masiva del espacio aéreo por macrófagos. El patrón histopatológico de RBIID y DIP se pueden sobreponer, siendo los principales elementos diferenciadores entre ambas entidades, la distribución y extensión de las lesiones: compromiso bronquiolo-céntrico en RBIID y difuso en DIP. Se ha planteado que la RB, RBIID y DIP pueden constituir diferentes fases de una misma enfermedad asociada al consumo de tabaco, lo cual aún es motivo de controversia. Con el propósito de ilustrar este problema, se presenta el caso clínico de un paciente fumador que consultó por disnea progresiva, tos e infiltrados pulmonares bilaterales sugerentes de enfermedad pulmonar difusa asociada al tabaquismoThe relationship between cigarette smoke and interstitial lung diseases (ILD is not clear. Respiratory bronchiolitis (RB, usually found as an incidental histologic abnormality in otherwise asymptomatic smokers, is characterized by the accumulation of cytoplasmic golden-brown-pigmented macrophages within respiratory bronchioles. A small proportion of smokers have a more exaggerated response that, in addition to the bronchiole-centered lesions, provokes interstitial and air spaces inflammation and fibrosis extending to the nearby alveoli. This set of histologic

  4. La violencia sexual asociada al conflicto y las implicaciones políticas de investigaciones recientes

    Directory of Open Access Journals (Sweden)

    Elisabeth Jean Wood

    2016-07-01

    Full Text Available La academia ha venido documentando un creciente número de modalidades de violencia sexual asociadas a los conflictos, sus causas y la gran variabilidad que existe en cuanto a su ejecución por parte de las organizaciones armadas. En este trabajo resumo los resultados de investigaciones recientes sobre dicha variabilidad, con énfasis en los hallazgos que contradicen o complican las creencias populares. Luego, presento varias interpretaciones sobre la afirmación de que esa violencia es parte de una continuidad entre tiempos de paz y de guerra. Después de analizar las investigaciones recientes sobre las dinámicas internas de las organizaciones armadas, sugiero que las violaciones sexuales a gran escala a menudo ocurren como una práctica, en vez de una estrategia. Por último, propongo algunos principios para guiar las políticas en vista de las investigaciones recientes

  5. Estudio de las preocupaciones asociadas al embarazo en un grupo de embarazadas primigestas chilenas

    Directory of Open Access Journals (Sweden)

    Chamarrita Farkas

    2008-05-01

    Full Text Available Este artículo se centra en la identificación de las preocupaciones y temores que surgen en el período del primer embarazo. Se utiliza una metodología cualitativa, con un diseño transversal, exploratorio y descriptivo. La muestra se compone de 17 embarazadas primigestas de 19 a 40 años y nivel socio-económico medio, que asistieron a dos talleres de “Promoción del primer vínculo” con una frecuencia semanal durante 6 semanas. A partir de las transcripciones de las sesiones, se identificaron y construyeron categorías de respuesta asociadas a temores y preocupaciones de esta etapa. Los resultados se presentan considerando los temores y preocupaciones asociados al embarazo, al parto y a la primera etapa de la maternidad.

  6. Factores de riesgo asociadas a la enfermedad Chagas en comunidades rurales en Lara, Venezuela

    Directory of Open Access Journals (Sweden)

    Zully Briceño

    2014-06-01

    Full Text Available La reinfestación por vectores secundarios es un problema emergente para la transmisión de la enfermedad de Chagas. Objetivo: Realizar un análisis comparativo para determinar los factores de riesgo asociados a la seropositividad en humanos. Materiales y Métodos: Estudio ecoentomológico y seroepidemiológico realizado en dos comunidades del Estado Lara, infestadas por Triatoma maculata o Panstrongylus geniculatus. Resultados: Guariquito (bosque húmedo tropical templado intervenido para actividad agrícola mostró una seroprevalencia (SP canina del 33,33 % y humana del 6,81 % asociada a: menores de 40 años, vector en vivienda anterior, comer animales de caza, migración rural, reconocimiento y contacto con el vector, siendo factores protectores conocimiento del vector y haber vivido en ranchos; infestación 20,45 %, colonización 0 % e infección 18,75 %; ninfas capturadas en cuevas de Xenarthra, los cuales se encontraron infectados (20 %, al igual que Rodentias (25 %. Cauderales (región semidesértica: SP humana del 11,56 % asociada a: mayores de 40 años, vector en vivienda anterior tipo rancho, comer animales de caza, migración rural, reconocimiento y contacto con el vector, siendo factor protector presencia de caninos en la vivienda, los cuales fueron seronegativos; infestación 5,51 %, colonización 0 % e infección-vivienda 0 %; ninfas y Chiropteras no infectadas fueron capturadas en Cactáceas. Conclusión: Panstrongylus geniculatus es responsable de la transmisión reciente en regiones intervenidas de bosque tropical húmedo y con reservorios de los géneros Xenarthra y Rodentia; Tm tiene capacidad vectorial limitada debido a bajos índices de infección producto de sus fuentes de alimento.

  7. Neumonía intersticial linfoidea asociada a inmunodeficiencia común variable

    Directory of Open Access Journals (Sweden)

    Gonzalo Peralta

    2011-10-01

    Full Text Available La neumonía intersticial linfoidea (NIL es una rara entidad, descripta como hiperplasia no neoplásica del tejido linfoide pulmonar y clasificada dentro de las enfermedades intersticiales idiopáticas. Se la ha descripto asociada a infección por HIV, fenómenos autoinmunes, hipergamaglobulinemia policlonal o menos frecuentemente a hipogammaglobulinemia. Presentamos una paciente de 66 años de edad con diabetes mellitus, síndrome de Sjögren e hipertensión arterial, derivada a nuestro centro por tos seca y disnea clase funcional II-III. En el examen físico presentaba rales tipo “velcro” bibasales y esplenomegalia. Los estudios de laboratorio evidenciaron plaquetopenia (50 000/mm³ e hipogammaglobulinemia; la tomografía axial computarizada (TAC de tórax mostró compromiso intersticial bibasal, con nódulos peribroncovasculares menores a un centímetro. Se realizó una videotoracoscopia con biopsia pulmonar, la anatomía patológica mostró hallazgos compatibles con neumonía intersticial linfoidea. Se inició tratamiento con metilprednisona 40 mg/día vía oral e infusión endovenosa de gammaglobulina 500 mg/kg, mensual, evolucionando con mejoría clínico-radiológica. Por persistencia de plaquetopenia, asociada a hiperesplenismo, se realizó esplenectomía con buena respuesta. En la anatomía patológica no se observo clonalidad linfoide.

  8. Big bacteria

    DEFF Research Database (Denmark)

    Schulz, HN; Jørgensen, BB

    2001-01-01

    , the 80 x 600 mum large Epulopiscium sp. from the gut of tropical fish, are presumably living in a very nutrient-rich medium. Many large bacteria contain numerous inclusions in the cells that reduce the volume of active cytoplasm. The most striking examples of competitive advantage from large cell size...

  9. Epidemia de neumonía asociada a ventilación mecánica en Mérida, Yucatán An outbreak of ventilator-associated pneumonia in Merida, Yucatán

    Directory of Open Access Journals (Sweden)

    Mussaret Zaidi

    1999-01-01

    Full Text Available OBJETIVO. Determinar las principales características epidemiológicas, clínicas y microbiológicas de una epidemia de neumonía asociada a ventilación mecánica en una unidad de cuidados intensivos en Mérida, Yucatán. MATERIAL Y MÉTODOS. Se diseñó un estudio prospectivo y observacional de 11 meses para determinar incidencia, mortalidad, reservorios potenciales, agentes etiológicos y sus patrones de sensibilidad antimicrobiana. RESULTADOS. La incidencia de neumonía asociada a ventilador fue de 74%. La mortalidad cruda fue de 88%, comparada con una mortalidad esperada de 19.5%. Se aislaron bacterias gramnegativas en 98% de los cultivos, de las cuales 46% fueron sensibles a cefalosporinas de tercera generación, 59% a cefalosporinas de cuarta generación, 70% a ciprofloxacina y 100% a imipenem. Se aislaron Klebsiella pneumoniae y Pseudomonas aeruginosa de algunos circuitos del ventilador y el lavado. CONCLUSIONES. La elevada incidencia de neumonía y la mortalidad asociada en esta unidad de cuidados intensivos se pueden atribuir a la falta de medidas de control de infecciones y a una elevada prevalencia de gérmenes multirresistentes que se relaciona con el uso desmesurado e irracional de antibióticos.OBJECTIVES. To determine the main epidemiological, clinical, and microbiologic characteristics of an outbreak of ventilator-associated pneumonia at an intensive care unit in Yucatan. MATERIAL AND METHODS. An 11-month prospective and observational study was designed to determine incidence, mortality, potential reservoirs, etiologic agents and antibiotic susceptibility patterns. RESULTS. The incidence of ventilator-associated pneumonia was 74%. The crude mortality rate was 88% compared to a 19.5% expected-mortality rate. Gram-negative bacteria were isolated from 98% of the cultures, of which 46% were susceptible to third generation cephalosporins, 59% to fourth generation cephalosporins, 70% to ciprofloxacin and 100% to imipenem. Klebsiella

  10. Osteonecrosis de los maxilares asociada al empleo de bifosfonatos Bisphosphonate-associated osteonecrosis of the jaw

    Directory of Open Access Journals (Sweden)

    J.L. del Castillo Pardo de Vera

    2007-10-01

    Full Text Available Los bifosfonatos constituyen un grupo de fármacos inhibidores de la resorción ósea, utilizados en el tratamiento de numerosas patologías como la osteoporosis, la enfermedad de Paget, el mieloma múltiple, la hipercalcemia maligna y las metástasis óseas asociadas al cáncer de mama o de próstata. El principal efecto farmacológico de los bifosfonatos es la inhibición de la resorción ósea, mediante una disminución de la actividad de los osteoclastos, sin intervenir en la formación y mineralización del hueso. Son fármacos utilizados a nivel mundial con unos claros beneficios contrastados clínicamente. Numerosas publicaciones durante los últimos tres años, y debido a su utilización masiva, consideran que la osteonecrosis de los maxilares está asociada al tratamiento con bifosfonatos. Es importante que los pacientes sean informados del riesgo de presentarse esta complicación, para tener la oportunidad de someterse a procedimientos dentales previos al inicio del tratamiento. Las medidas preventivas deben realizarse antes, durante y después del tratamiento con bifosfonatos. El tratamiento quirúrgico debe reservarse para aquellos pacientes que presenten síntomas. Son necesarias nuevas investigaciones que clarifiquen esta complicación.Bisphosphonates constitute a group of inhibitors of bone resorption that are used for treating many disor-ders such as osteoporosis, Paget´s disease, multiple myeloma, malignant hypercalcemia and bone metas-tases associated with breast and prostate cancer. The main pharmacological effect of bisphosphonates is the inhibition of bone resorption, mediated by a decreased function of osteoclasts without interfering in bone formation and mineralization. These drugs are used worldwide, with clear and clinically proven benefits. Several publications within the last three years consider osteonecrosis of the jaw to be associated with bisphosphonate therapy as a result of their extensive use. It is important

  11. Manejo de praderas asociadas de gramíneas y leguminosas para pastoreo en el trópico

    Directory of Open Access Journals (Sweden)

    Saúl Rojas Hernández

    2005-05-01

    Full Text Available ste trabajo es una revisión bibliográfica sobre el manejo de praderas asociadas de gramíneas con leguminosas para mejorar la calidad de la dieta del animal e incrementar la productividad de las praderas, así como mantener la proporción de los componentes botánicos en espacio y tiempo.Tipo de trabajo: Articulo de revisión en el área de forrajes.

  12. Evaluación de la memoria declarativa asociada con contenido emocional en pacientes lobectomizados

    Directory of Open Access Journals (Sweden)

    Silvia Botelho

    2008-01-01

    Full Text Available La participación del lóbulo temporal en la memoria para eventos emocionales, ha sido evaluada utilizando la Prueba auditivo-visual, cuyo contenido emocional es presentado en narrativas complejas. El presente estudio examinó si el desempeño en el Token Test, afectaba la retención a largo plazo de información alertante emocionalmente en pacientes con lobectomía temporal unilateral. Se evaluaron 48 participantes, a quienes se les aplicó: Trail Making Test, Token Test y una Prueba auditivo-visual. De manera general, la ausencia del efecto de potenciación mnemónico encontrado en pacientes con lobectomía temporal izquierda no estuvo correlacionada con el rendimiento en el Token Test. En conjunto, se muestra la importancia de la integridad del lóbulo temporal izquierdo para la potenciación de la memoria declarativa asociada a contenido emocional

  13. Prácticas culinarias asociadas al consumo de frijoles en familias costarricenses.

    Directory of Open Access Journals (Sweden)

    Shirley Rodríguez-González

    2015-01-01

    Full Text Available El objetivo de este trabajo fue identificar las prácticas asociadas al consumo de frijoles en una población rural y una urbana de Costa Rica. El estudio fue desarrollado en el 2005, en una muestra de 475 familias que acostumbran preparar y consumir frijoles (223 de la zona rural de Jesús de Atenas y 252 de la zona urbana en La Unión de Tres Ríos. En estas familias se entrevistó a la persona encargada de la preparación de los alimentos. Este estudio mostró un consumo per cápita de frijoles de 37,5 g/p/día de peso crudo. El consumo per cápita por área geográfica, fue mayor en zona rural (46,8 + 25 g/p/d que en la zona urbana (37,5 + 23 g/p/d (F=18,031, p=0,000. Los factores asociados al consumo se diferenciaron por zona; en la rural se relacionaron con algunas características de la persona que prepara los alimentos, prácticas de preparación de los frijoles y con la razón de consumo manifestada, mientras que en la zona urbana los factores asociados estuvieron relacionados únicamente con las prácticas culinarias.

  14. Rumen bacteria

    International Nuclear Information System (INIS)

    The rumen is the most extensively studied gut community and is characterized by its high population density, wide diversity and complexity of interactions. This complex, mixed microbial culture is comprised of prokaryote organisms including methane-producing archaebacteria, eukaryote organisms, such as ciliate and flagellate protozoa, anaerobic phycomycete fungi and bacteriophage. Bacteria are predominant (up to 1011 viable cells per g comprising 200 species) but a variety of ciliate protozoa occur widely (104-106/g distributed over 25 genera). The anaerobic fungi are also widely distributed (zoospore population densities of 102-104/g distributed over 5 genera). The occurrence of bacteriophage is well documented (107-109 particles/g). This section focuses primarily on the widely used methods for the cultivation and the enumeration of rumen microbes, especially bacteria, which grow under anaerobic conditions. Methods that can be used to measure hydrolytic enzymes (cellulases, xylanases, amylases and proteinases) are also described, along with cell harvesting and fractionation procedures. Brief reference is also made to fungi and protozoa, but detailed explanations for culturing and enumerating these microbes is presented in Chapters 2.4 and 2.5

  15. Infecciones intrahospitalarias asociadas a dispositivos invasivos en unidades de cuidados intensivos de un hospital nacional de Lima, Perú

    Directory of Open Access Journals (Sweden)

    Omayra Chincha

    2013-12-01

    Full Text Available Con el objetivo de describir la incidencia de infecciones intrahospitalarias asociadas a dispositivos invasivos en unidades de cuidados intensivos (UCI del Hospital Nacional Cayetano Heredia se realizó un estudio observacional retrospectivo utilizando datos de la Oficina de Epidemiología y Salud Ambiental durante los años 2010 al 2012. Se notificó un total de 222 infecciones intrahospitalarias, la UCI de Medicina tuvo la incidencia por 1000 días de uso del dispositivo más alta para neumonía asociada a ventilador mecánico (28,6; infección del torrente sanguíneo asociado a catéter venoso central (11,9, e infección del tracto urinario asociado a catéter (8,1. Los principales agentes infecciosos aislados fueron Pseudomona sp. (32,3% en la UCI de emergencia, Staphylococcus coagulasa negativo(36% en la UCI de medicina y Candida sp (69,2% en la UCI de cirugía. Las tasas de infecciones asociadas a dispositivos invasivos se reportaron altas semejantes a otros hospitales nacionales con limitados recursos e infraestructura

  16. Infecciones intrahospitalarias asociadas a dispositivos invasivos en unidades de cuidados intensivos de un hospital nacional de Lima, Perú

    Directory of Open Access Journals (Sweden)

    Omayra Chincha

    2013-10-01

    Full Text Available Con el objetivo de describir la incidencia de infecciones intrahospitalarias asociadas a dispositivos invasivos en unidades de cuidados intensivos (UCI del Hospital Nacional Cayetano Heredia se realizó un estudio observacional retrospectivo utilizando datos de la Oficina de Epidemiología y Salud Ambiental durante los años 2010 al 2012. Se notificó un total de 222 infecciones intrahospitalarias, la UCI de Medicina tuvo la incidencia por 1000 días de uso del dispositivo más alta para neumonía asociada a ventilador mecánico (28,6; infección del torrente sanguíneo asociado a catéter venoso central (11,9, e infección del tracto urinario asociado a catéter (8,1. Los principales agentes infecciosos aislados fueron Pseudomona sp. (32,3% en la UCI de emergencia, Staphylococcus coagulasa negativo(36% en la UCI de medicina y Candida sp (69,2% en la UCI de cirugía. Las tasas de infecciones asociadas a dispositivos invasivos se reportaron altas semejantes a otros hospitales nacionales con limitados recursos e infraestructura

  17. Implicación de rs924607 del gen CEP72 en la neurotoxicidad asociada a la vincristina en pacientes con leucemia linfoblastica aguda (LLA)

    OpenAIRE

    De Vicente Martínez, Beatriz

    2016-01-01

    Este trabajo se trata de un estudio estadístico de asociación entre el genotipo del SNP rs924607 presente en la región promotora del gen CEP72, y la neurotoxicidad asociada a la vincristina, en pacientes pediátricos de Leucemia Linfoblástica Aguda. El objetivo es determinar si el alelo presente en dicho SNP puede ser empleado como biomarcador para predecir la neurotoxicidad asociada a la vincristina.

  18. Macrofauna edáfica asociada con sistemas agroforestales en la Amazonía Colombiana

    Directory of Open Access Journals (Sweden)

    Juan Carlos Suárez Salazar

    2015-07-01

    Full Text Available La densidad, riqueza y diversidad de la macrofauna edáfica son afectadas, entre otros factores, por la configuración de los agroecosistemas y la estacionalidad de la precipitación. Con el fin de evaluar estos efectos en mayo y noviembre de 2011, correspondientes a épocas de máxima y mínima precipitación, respectivamente, se realizaron estudios sobre la composición de la macrofauna edáfica asociada con los arreglos agroforestales ubicados en el Centro de Investigaciones Macagual Cesar Augusto Estrada González, Amazonia, Caquetá, Colombia. El experimento se dispuso en un diseño completo al azar bifactorial con cuatro tratamientos (arreglos agroforestales: AB = abarco - Cariniana pyriformis Miers; CH = caucho Hevea brasiliensis (Willd. ex A. Juss. Müll. Arg. ; CP = caucho-parica Schizolobium amazonicum Huber; UV = uvito Genipa Americana L. y dos épocas (máxima y mínima precipitación, y cuatro repeticiones en parcelas divididas. Para explorar las relaciones entre los órdenes de macrofauna, se realizó un análisis de componentes principales y se evalúo el efecto de los arreglos agroforestales con una prueba de Monte Carlo. Los resultados mostraron que la densidad de la macrofauna fue mayor en el periodo de máxima precipitación (1129 individuos en comparación con el de mínima (598 individuos. Los arreglos agroforestales influyen sobre la presencia o ausencia de algunos grupos taxonómicos (P < 0.05 como Homoptera (Insecta y Raphidioptera (Insecta; además los UV y AB pueden favorecer a la macrofauna del estrés por sequía

  19. Pregnancy-associated purpura fulminans (PF Púrpura fulminans asociada al embarazo

    Directory of Open Access Journals (Sweden)

    Gisela de la Rosa Echavez

    2005-03-01

    Full Text Available

    PF is a serious cutaneous purpuric disease, associated with an intravascular disseminated coagulation syndrome. Among its known causes, besides those of thrombophilia, are viral and bacterial infections, mostly Neisseria meningitidis. During pregnancy there are alterations in the hemostatic mechanism. However, by themselves, they have not been shown to lead to PF. The case of a 22-year-old woman who developed PF during pregnancy, presumably due to her Escherichia coli urinary tract infection, is presented including clinical, paraclinical, therapeutic and surgical aspects. She recovered but suffered amputation of the distant phalanges of three toes in the left foot 

    La púrpura fulminans (pf es una enfermedad cutánea purpúrica aguda asociada a un síndrome de coagulación intravascular diseminada (CID. Sus causas conocidas incluyen infecciones virales y bacterianas así como trombofilias. Es sabido que durante el embarazo existen alteraciones en los mecanismos hemostáticos, sin embargo, no se ha demostrado que estos fenómenos por sí solos ayuden al desarrollo de la PF. Se describe el caso de una mujer de 22 años, quien tuvo PF en circunstancias inusuales tales como el desarrollo de su cuadro durante el embarazo y el origen probable en una infección por E. coli. Se presentan los hallazgos clínicos, las intervenciones médicas y quirúrgicas y el desenlace. La paciente sobrevivió, pero hubo necesidad de amputarle las falanges distales de tres artejos del pie izquierdo.

  20. Patrón de las alteraciones dentales asociadas a la impactación del canino maxilar por palatino

    OpenAIRE

    Olivera Aguilar, Esther

    2015-01-01

    La tesis doctoral se ha realizado para poder encontrar un método de diagnóstico precoz de la impactación del canino maxilar por palatino, mediante la detección temprana de otras alteraciones dentales asociadas y así poder aplicar tratamientos tempranos, que mejoren el pronóstico de la impactación del canino maxilar por palatino. La impactación del canino maxilar por palatino, supone la alteración del trayecto eruptivo del mismo, que lo conduce a la zona palatina. Los pacientes con esta altera...

  1. Fauna silvestre asociada a ganado vacuno doble propósito en sistema de silvopastoreo, Pinto, Magdalena, Colombia

    OpenAIRE

    Jaime De La Ossa V.; Luz Botero A

    2015-01-01

    Objetivo. Evaluar la biodiversidad faunística asociada a ganadería vacuna de doble propósito en dos potreros estructurados con Botriochloa pertusa (colosoana) como herbácea dominante, uno de ellos plantado con Crescentia cujete (Bignoniaceae) como fuente de alimento adicional y otro con escaso y disperso arbolado. Materiales y métodos. El área de estudio está ubicada en el municipio de Pinto, Magdalena. Cada potrero evaluado fue de 10 ha, se mantuvo en cada uno un lote de quince vacas (½ Cebú...

  2. Condilomatosis genital y embarazo asociada a corioamnionitis y parto prematuro Genital condylomatosis and pregnancy associated with chorioamnionitis and premature delivery

    OpenAIRE

    I. Martínez Montero; M.A. García Mutiloa; R. Ezcurra; Campo, G.; E. Arpa; R. Obregozo

    2004-01-01

    Los condilomas genitales están producidos por el virus del papiloma humano. En muchas ocasiones se asocian a otras infecciones genitales (hongos, tricomonas y vaginosis). El embarazo favorece la aparición de condilomas en la región anogenital. A propósito de un caso de condilomatosis genital asociada a corioamnionitis y que desencadenó un parto prematuro realizamos una revisión de la literatura.Genital condylomas are produced by the human papilloma virus. On many occasions they are associated...

  3. Infecciones intrahospitalarias asociadas a dispositivos invasivos en unidades de cuidados intensivos de un hospital nacional de Lima, Perú

    OpenAIRE

    Omayra Chincha; Elia Cornelio; Violeta Valverde; Mónica Acevedo

    2013-01-01

    Con el objetivo de describir la incidencia de infecciones intrahospitalarias asociadas a dispositivos invasivos en unidades de cuidados intensivos (UCI) del Hospital Nacional Cayetano Heredia se realizó un estudio observacional retrospectivo utilizando datos de la Oficina de Epidemiología y Salud Ambiental durante los años 2010 al 2012. Se notificó un total de 222 infecciones intrahospitalarias, la UCI de Medicina tuvo la incidencia por 1000 días de uso del dispositivo más alta para neumonía ...

  4. ESPECIES DE GALLINA CIEGA (COLEOPTERA: SCARABAEOIDEA) ASOCIADAS AL CULTIVO DE MAÍZ EN AHOME, SINALOA, MÉXICO

    OpenAIRE

    G. Antonio Lugo-García; L. Delia Ortega- Arenas; Agustín Aragón-García; Héctor González-Hernández; Jesús Romero-Nápoles; Álvaro Reyes-Olivas; M. Ángel Morón

    2012-01-01

    En algunas regiones del estado de Sinaloa, México, se considera que las larvas de coleópteros Melolonthidae conocidas como gallina ciega son una de las principales plagas rizófagas del maíz (Zea mays). Por ello, el objetivo del presente estudio fue conocer las especies de gallina ciega asociadas al cultivo de maíz en el Valle del Carrizo, Sinaloa. Se realizaron muestreos de suelo de septiembre de 2008 a marzo de 2009 y se recolectaron adultos de julio a octubre de 2008, dos veces por se...

  5. Diagnóstico prenatal de ciclopía asociada con trisomía 13

    Directory of Open Access Journals (Sweden)

    Harry Pachajoa

    2008-03-01

    Full Text Available Se presenta un caso de ciclopía con diagnóstico prenatal por ecografía bidimensional y tridimensional, a quien se le realizó cordocentesis, el cariotipo en sangre fetal con bandeo G mostró trisomía 13 libre, las características fenotípicas se confirmaron al examen físico del recién nacido. Se hace una revisión de la literatura de ciclopía asociada con la trisomía 13 y se destacan aspectos de importancia en la ecografía prenatal.

  6. Implicaciones medioambientales asociadas a un vertedero de residuos sólidos urbanos.El caso de Villamayor

    OpenAIRE

    Septién Rodríguez, Marta

    2011-01-01

    [ES] Estudio sobre las implicaciones medioambientales asociadas a un vertedero de residuos sólidos urbanos. Se estudia el caso de Villarmayor (Salamanca). La gestión de residuos es un problema importante a nivel Mundial. Las poblaciones de los países en desarrollo están creciendo rápidamente y, cada vez más, llegando a ser zonas urbanizadas. En los países desarrollados, el consumismo lleva a la sustitución rápida de las mercancías y grandes cantidades de envases desechados. Ambas tendencias l...

  7. Optimización de la biorremediación en relaves de cianuración adicionando nutrientes y microorganismos

    Directory of Open Access Journals (Sweden)

    Jasmin Hurtado

    2012-11-01

    Full Text Available El objetivo del presente trabajo fue encontrar los parámetros óptimos para el desarrollo de los proceso de bioremediacion de relaves de cianuración, mediante experimentos factoriales a nivel de columnas con la adición de nutrientes y el empleo de bacterias sulfato reductoras (BSR para estabilizar iones metálicos mediante la formación de sulfuros y bacterias capaces de biodegradar cianuro (BC. Se aislaron BSR de relave y se usó un inoculo previamente aislado de BC. Se realizó una prueba de adaptación a relave y una prueba en columnas para probar: (1 el efecto del empleo de 1 y 10 mM de lactato para incrementar la actividad de BSR; y (2 adición de 0,1 y 1 mM de acetato de sodio y ácido fosfórico para mejorar la actividad de BC. Con las mejores condiciones encontradas se realizó una prueba a nivel de columnas donde se adicionó un cultivo mixto (BSR-BC y una mezcla de lactato y acetato en concentraciones de 1 mM y 10 mM. Se encontró que los nutrientes incrementaban la reducción de sulfatos un 48% en promedio y la adición de inoculo un 42%. La bioremediacion de cianuro se mantuvo en 12% sin efecto en la adición de nutrientes o inoculo. Se probó en dos relaves adicionales y la adición de lactato de sodio 1 mM permitió la inducción de BSR en 8 días en uno de ellos.

  8. Nuevas evidencias de deformaciones cuaternarias asociadas a la falla Sierra chica, Sierras pampeanas de Córdoba

    Directory of Open Access Journals (Sweden)

    Guillermo L Sagripanti

    2012-12-01

    Full Text Available En la intraplaca argentina, entre los 31º 45' y 32º 45' de latitud S, en el frente occidental de la Sierra Chica, Sierras Pampeanas de Córdoba, la presencia de morfologías superficiales y deformaciones en sedimentos cuaternarios permiten deducir que la actividad tectónica neógena en la región, tuvo continuidad en el Holoceno y probablemente ha tenido asociada la ocurrencia de paleoterremotos. Los objetivos de la presente contribución son presentar nuevas evidencias de deformaciones cuaternarias asociadas a la falla Sierra Chica, extender su traza hacia el sur en la llanura y hacer una estimación preliminar del potencial sismogénico asociado a esta estructura. Se relevaron siete perfiles transversales a la traza de una falla secundaria del frente principal de levantamiento de la Sierra Chica. Estos presentan el basamento cristalino precámbrico, depósitos conglomerádicos y sedimentos no cohesivos cuaternarios, afectados por deformaciones dúctiles y frágiles correspondientes a reactivaciones pleistocenas y holocenas de la estructura. Los resultados obtenidos han permitido extender la traza de la falla hacia el S en la llanura hasta el arroyo Tegua, relevar estructuras deformacionales en sedimentos finos no reportadas hasta el presente y estimar la magnitud máxima de un terremoto futuro, entre Ms 6,7-7,5 y Mw=7,5, asociado a la falla Sierra Chica.

  9. Jerarquía holística de las dificultades asociadas a las estrategias aditivas de cálculo mental

    OpenAIRE

    Tomás ORTEGA DEL RINCÓN; Ortiz, María

    2006-01-01

    En el presente trabajo de investigación se da un procedimiento para obtener una jerarquía holística de las difi cultades asociadas a las estrategias aditivas de cálculo mental. Este procedimiento se basa en las actividades básicas de cálculo que determinan la estrategia, y con él se establece una clasifi cación de tipo holístico de las difi cultades de cálculo asociadas a dichas estrategias. El artículo termina enunciando las conclusiones del trabajo y señalando un par de problemas abiertos....

  10. Estudio de las torres de refrigeración asociadas a brotes comunitarios de legionelosis Study of refrigeration towers associated with community outbreaks of legionellosis

    OpenAIRE

    Albert Pérez Lleonart; Susana Chacón Villanueva; Fernando Parrilla Valero

    2007-01-01

    Objetivo: Evaluar los factores de riesgo de las torres de refrigeración asociadas a un brote comunitario de legionelosis según sus características de mantenimiento y la calidad del agua. Método: Comparar los datos recogidos entre los 4 tipos de torres de refrigeración: control 1, control 2, probable y confirmada. Se han estudiado un total de 184 torres de refrigeración asociadas a 17 brotes comunitarios de legionelosis de la provincia de Barcelona durante el año 2004, de las cuales 112 son co...

  11. Cuidados de enfermería en la prevención de la neumonía asociada a ventilación mecánica

    OpenAIRE

    Camarón Rollán, Miguel Ángel

    2014-01-01

    La neumonía asociada a ventilación mecánica, es una de las complicaciones más frecuentes asociada a la ventilación mecánica invasiva ,con una incidencia muy variable (del 10 al 70%) y una mortalidad del 40 al 80%, responsable del aumento de la mortalidad, la prolongación en el tiempo de estancia hospitalaria y en consecuencia el aumento del gasto sanitario. El proceso de atención de enfermería, basado en el conocimiento de las posibles complicaciones y efectos secundarios de la ventilación...

  12. Epidemia de neumonía asociada a ventilación mecánica en Mérida, Yucatán

    OpenAIRE

    Zaidi Mussaret; Martín Gloria; Rosado Rilke

    1999-01-01

    OBJETIVO. Determinar las principales características epidemiológicas, clínicas y microbiológicas de una epidemia de neumonía asociada a ventilación mecánica en una unidad de cuidados intensivos en Mérida, Yucatán. MATERIAL Y MÉTODOS. Se diseñó un estudio prospectivo y observacional de 11 meses para determinar incidencia, mortalidad, reservorios potenciales, agentes etiológicos y sus patrones de sensibilidad antimicrobiana. RESULTADOS. La incidencia de neumonía asociada a ventilador fue de 74%...

  13. Bacteria isolated from amoebae/bacteria consortium

    Science.gov (United States)

    Tyndall, Richard L.

    1995-01-01

    New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

  14. Evaluación del potencial biofertilizante de bacterias diazótrofas aisladas de suelos con cultivo de cacao (Theobroma cacao L.)

    OpenAIRE

    Adriana Zulay Argüello-Navarro; Laura Yolima Moreno-Rozo

    2014-01-01

    La adaptabilidad del cacao (Theobroma cacao L.) en condiciones adversas permite sugerir que la microbiota asociada con la rizosfera desempeña una función importante para la nutrición y el desarrollo de la planta. En el trabajo se evaluó el potencial biofertilizante de bacterias fijadoras de nitrógeno (diazótrofas) aisladas de suelos cacaoteros por la técnica de diluciones seriadas. Las bacterias se aislaron en medios semiselectivos (NFb, JMV, LGI, JNFb). Los aislados puros se caracterizaron m...

  15. Condilomatosis genital y embarazo asociada a corioamnionitis y parto prematuro Genital condylomatosis and pregnancy associated with chorioamnionitis and premature delivery

    Directory of Open Access Journals (Sweden)

    I. Martínez Montero

    2004-12-01

    Full Text Available Los condilomas genitales están producidos por el virus del papiloma humano. En muchas ocasiones se asocian a otras infecciones genitales (hongos, tricomonas y vaginosis. El embarazo favorece la aparición de condilomas en la región anogenital. A propósito de un caso de condilomatosis genital asociada a corioamnionitis y que desencadenó un parto prematuro realizamos una revisión de la literatura.Genital condylomas are produced by the human papilloma virus. On many occasions they are associated with other genital infections (fungi, trichomonas and vaginosis. Pregnancy favours the appearance of condylomas in the anogenital region. On the occasion of a case of genital condylomatosis associated with chorioamnionitis that resulted in a premature delivery, we carry out a review the literature.

  16. Tamaño óptimo de parcela en calabaza asociada con maíz

    OpenAIRE

    C. Villanueva-Verduzco; I. Meneses-Márquez; J. A. Mejía-Contreras; J. D. Molina-Galán; S. Miranda-Colín

    2006-01-01

    Se determinó el coeficiente de variación (CV) en los caracteres de fruto (número, peso, largo, ancho, color y textura externa), de pulpa (grosor, color y sabor) y de la semilla (peso, largo y ancho), para superficies de 2.7, 5.4, 8.1, 10.8 y 13.5 m2, con el objetivo de conocer el tamaño óptimo de parcela en calabaza (Cucurbita pepo L.) asociada con maíz (Zea mays L.). La investigación se realizó en Chapingo, México, en dos localidades de evaluación: San Martín y Lomas de San Juan. Se utilizar...

  17. Estudio de variables asociadas a la psicoterapia grupal en los procesos de duelo patológico.

    OpenAIRE

    Juan Díaz Curiel

    2011-01-01

    Se estudian variables asociadas al proceso terapéutico grupal (10 sesiones de 75 minutos) de 24 sujetos adultos (23 mujeres y 1 varón) distribuídos en cuatro grupos de terapia durante los años 2007-2010 con diagnóstico de duelo complicado (DC). El DC se evalúa a través de la Escala de Prigerson (punto de corte más de 24) (Prigerson, 1995, Traducción Española Olmeda y García, 2006). Los pacientes pertenecen al Equipo de Salud (ESM) de Vallecas Villa y acuden remitidos por el médico de Atención...

  18. Vasculitis asociadas a anticuerpos anti-citoplasma de neutrófilos: Clínica y tratamiento

    Directory of Open Access Journals (Sweden)

    María Virginia Paolini

    2013-04-01

    Full Text Available Las vasculitis asociadas a anticuerpos anti-citoplasma de neutrófilos (ANCA comprenden a un grupo de enfermedades caracterizadas por la inflamación de la pared de pequeños vasos. Analizamos las características epidemiológicas y clínicas en una serie de 47 pacientes: 23 (49% granulomatosis de Wegener (GW, 15 (32% poliangeítis microscópica (PAM y nueve (19% vasculitis limitada al riñón (VLR. La edad media al inicio de los síntomas fue de 50.7 ± 14.9 años. La manifestación clínica más frecuente fue el compromiso renal en 41 (87% pacientes, seguido por el pulmonar en 26 (55% y el otorrinolaringológico en 17 (36%. En 26 (55% se asoció compromiso renal y pulmonar. La forma clínica más frecuente fue la generalizada en 23 (49%, seguida por la grave en 18 (38%. El 89% presentaron determinaciones de ANCA positivas. Cuatro (8% no recibieron tratamiento inmunosupresor de inicio. De los 43 que recibieron tratamiento de inicio, 29 (67% tuvieron remisión completa, con un tiempo de remisión promedio de 35.3 meses. Once (26% presentaron recaídas, diez (91% recaídas mayores y uno (9% menor. Doce (28% fallecieron, siete en forma temprana y cinco durante la evolución de la enfermedad. Quince (31% evolucionaron a insuficiencia renal crónica. Los 26 pacientes en seguimiento tuvieron respuesta al tratamiento y 20 (77% de ellos estaban en remisión al finalizar el estudio. Las vasculitis asociadas a ANCA continúan siendo enfermedades de alta morbilidad y mortalidad, a pesar de las mejorías logradas con los tratamientos inmunosupresores.

  19. Bleach vs. Bacteria

    Science.gov (United States)

    ... Articles | Inside Life Science Home Page Bleach vs. Bacteria By Sharon Reynolds Posted April 2, 2014 Your ... hypochlorous acid to help kill invading microbes, including bacteria. Researchers funded by the National Institutes of Health ...

  20. Bacteria and lignin degradation

    Institute of Scientific and Technical Information of China (English)

    Jing LI; Hongli YUAN; Jinshui YANG

    2009-01-01

    Lignin is both the most abundant aromatic (phenolic) polymer and the second most abundant raw material.It is degraded and modified by bacteria in the natural world,and bacteria seem to play a leading role in decomposing lignin in aquatic ecosystems.Lignin-degrading bacteria approach the polymer by mechanisms such as tunneling,erosion,and cavitation.With the advantages of immense environmental adaptability and biochemical versatility,bacteria deserve to be studied for their ligninolytic potential.

  1. Intracellular Bacteria in Protozoa

    Science.gov (United States)

    Görtz, Hans-Dieter; Brigge, Theo

    Intracellular bacteria in humans are typically detrimental, and such infections are regarded by the patients as accidental and abnormal. In protozoa it seems obvious that many bacteria have coevolved with their hosts and are well adapted to the intracellular way of life. Manifold interactions between hosts and intracellular bacteria are found, and examples of antibacterial resistance of unknown mechanisms are observed. The wide diversity of intracellular bacteria in protozoa has become particularly obvious since they have begun to be classified by molecular techniques. Some of the bacteria are closely related to pathogens; others are responsible for the production of toxins.

  2. Diarrea del viajero asociada a Aeromonas hydrophila Traveller's diarrohea caused by Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    M. L. Pita Toledo

    2001-06-01

    Full Text Available Aeromonas hydrophila es una bacteria que se encuentra frecuentemente en aguas dulces y salobres. Desde hace varios años se conoce que determinadas cepas de la especie pueden causar enfermedad en pescados y en anfibios, existiendo cierta controversia sobre su patogeneicidad en humanos. No obstante, puede dar lugar a infección en personas, que la adquieren bien a través de heridas abiertas o bien por ingestión de alimentos o agua contaminados. Sin embargo, en prácticamente la totalidad de las publicaciones se hace referencia a casos aislados más que a brotes producidos por esta bacteria. Generalmente la infección por A. hydrophila da lugar a gastroenteritis en personas sanas, pudiendo generar una septicemia en individuos inmunodeprimidos.En 1998 se produjo una alarma en el sector hotelero por un incremento considerable de los casos de gastroenteritis entre los turistas que acudían durante sus vacaciones a determinadas zonas costeras de la isla de Tenerife.Tras tener conocimiento de la situación, la Dirección General de Salud Pública inició una investigación epidemiológica con el objetivo de conocer la magnitud real del problema detectado e identificar los factores asociados a la misma, para poner en marcha las medidas correctoras y de control necesarias. El análisis inicial permitió determinar que se trataba de un proceso de gran magnitud en su extensión aunque de carácter leve, que afectaba únicamente a los turistas en una zona costera en concreto, compatible por lo tanto con la diarrea del viajero, planteándose un origen probablemente hídrico.Aeromonas hydrophila is a bacteria frequently found in fresh water and saline water. Certain strains of the species have been known to cause disease in fish and amphibians for several years, although some controversy exists about its ability to cause illness in humans. Nevertheless, either through open wounds or contaminated food or water, it can give rise to infection. However, almost

  3. Microbiota de jamones de cerdo cocidos asociada al deterioro por abombamiento del empaque

    Directory of Open Access Journals (Sweden)

    Juliana Ossa

    2010-08-01

    Full Text Available Objetivo. Caracterizar la diversidad microbiana y calidad microbiológica e higiénico sanitaria de diferentes marcas de jamones de cerdo cocidos abombados y no abombados comprados en varios supermercados de Bogotá D.C. Materiales y métodos. Se analizaron 10 marcas diferentes de jamones de cerdo cocidos comprados en tres supermercados, refrigerados bajos las mismas condiciones del consumidor, durante 45 días. Se realizó los recuentos en placa de microorganismos de interés en la industria de alimentos y de inocuidad en las muestras con o sin distensión del empaque e identificación por pruebas bioquímicas y PCR para determinar la diversidad de la microbiota. Se aislaron cepas productoras de biopelículas provenientes de la superficie de una planta de alimentos de una de las marcas de los jamones investigadas. Resultados. Se identificaron un total de 139 cepas aisladas del producto terminado, de las cuales un 99% (137 cepas pertenecen al grupo de Bacterias Acido Lácticas (BAL, el 1% restante son levaduras. De las 31 cepas aisladas de las superficies en la zona de tajado, el 97% (30 cepas presentaron formación de biopelículas. Se determinó ausencia de patógenos tanto en el producto terminado como en las muestras de las superficies.Conclusiones. El deterioro causado por abombamiento del empaque fue asociado a la presencia de BAL, debido a que fueron encontradas en la zona de tajado y en el producto terminado, de este último únicamente se aislaron BAL, en mayor proporción cepas correspondientes al género de Lactobacillus sp.

  4. Genomics of Probiotic Bacteria

    Science.gov (United States)

    O'Flaherty, Sarah; Goh, Yong Jun; Klaenhammer, Todd R.

    Probiotic bacteria from the Lactobacillus and Bifidobacterium species belong to the Firmicutes and the Actinobacteria phylum, respectively. Lactobacilli are members of the lactic acid bacteria (LAB) group, a broadly defined family of microorganisms that ferment various hexoses into primarily lactic acid. Lactobacilli are typically low G + C gram-positive species which are phylogenetically diverse, with over 100 species documented to date. Bifidobacteria are heterofermentative, high G + C content bacteria with about 30 species of bifidobacteria described to date.

  5. Learning Chemistry from Bacteria

    OpenAIRE

    Clardy, Jon

    2013-01-01

    Dr. Jon Clardy Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Harvard University All animals, including humans, originated and evolved on a planet already teeming with bacteria, and the two kingdoms of life have been competing and cooperating through their joint history. Although bacteria are most familiar as pathogens, some bacteria produce small molecules that are essential for the biology of animals and other eukaryotes. This lecture explores some of...

  6. Inventario de la entomofauna asociada al cultivo de pitahaya amarilla (Selenicereus megalanthus Haw.) en Briceño (Boyacá)

    OpenAIRE

    Héctor Iván Patiño-Tiria; Jhon Wilson Martínez-Osorio; Álvaro Enrique Alvarado-Gaona

    2015-01-01

    Boyacá es uno de los departamentos con mayor producción de pitahaya amarilla en el país. Los estudios realizados sobre este cultivo son muy pocos, y el conocimiento de la entomofauna asociada a él es un punto de partida para realizar nuevas investigaciones que permitan identificar la entomofauna asociada a este cultivo en el municipio de Briceño (Boyacá). El desarrollo de esta investigación se llevó a cabo en plantaciones de pitahaya en tres fincas del municipio de Briceño (Boyacá). Se realiz...

  7. Inventario de la fauna asociada a hidrozoos en la ría de Ferrol (NO península Ibérica)

    OpenAIRE

    Varela, C.; Moreira, J.; Urgorri Carrasco, Victoriano, 1951-

    2009-01-01

    Los hidrozoos (Cnidaria: Hydrozoa) constituyen un sustrato de asentamiento para numerosas especies de organismos marinos. El estudio de cinco especies de hidrozoos coloniales (Sertularella polyzonias (Linneo, 1758), Nemertesia antennina (Linneo, 1758), N. ramosa Lamarck, 1816, Kirchenpaueria pinnata (Linneo, 1758), Aglaophenia pluma (Linneo, 1758)) en la Punta da Redonda (ría de Ferrol, NO península Ibérica) ha revelado que dichas especies albergan una fauna asociada muy diversa. ...

  8. Estudio de variables asociadas a la psicoterapia grupal en los procesos de duelo patológico.

    Directory of Open Access Journals (Sweden)

    Juan Díaz Curiel

    2011-01-01

    Full Text Available Se estudian variables asociadas al proceso terapéutico grupal (10 sesiones de 75 minutos de 24 sujetos adultos (23 mujeres y 1 varón distribuídos en cuatro grupos de terapia durante los años 2007-2010 con diagnóstico de duelo complicado (DC. El DC se evalúa a través de la Escala de Prigerson (punto de corte más de 24 (Prigerson, 1995, Traducción Española Olmeda y García, 2006. Los pacientes pertenecen al Equipo de Salud (ESM de Vallecas Villa y acuden remitidos por el médico de Atención Primaria para evaluar y tratar síntomas compatibles con duelo complicado. En otros casos el DC se detecta en las primeras entrevistas de evaluación, o bien a lo largo del tratamiento psiquiátrico o psicoterapéutico por los profesionales del ESM. Una vez finalizado el tratamiento grupal (TG se vuelve a pasar La Escala de Prigerson obteniendo como resultado diferencias significativas en las puntuaciones antes y después del tratamiento, indicador de que el duelo complicado mejora significativamente en los sujetos que han participado en el tratamiento grupal.

  9. How honey kills bacteria

    NARCIS (Netherlands)

    P.H.S. Kwakman; A.A. te Velde; L. de Boer; D. Speijer; C.M.J.E. Vandenbroucke-Grauls; S.A.J. Zaat

    2010-01-01

    With the rise in prevalence of antibiotic-resistant bacteria, honey is increasingly valued for its antibacterial activity. To characterize all bactericidal factors in a medical-grade honey, we used a novel approach of successive neutralization of individual honey bactericidal factors. All bacteria t

  10. Metallization of bacteria cells

    Institute of Scientific and Technical Information of China (English)

    LI; Xiangfeng; (黎向锋); LI; Yaqin; (李雅芹); CAI; Jun; (蔡军); ZHANG; Deyuan; (张德远)

    2003-01-01

    Bacteria cells with different standard shapes are well suited for use as templates for the fabrication of magnetic and electrically conductive microstructures. In this paper, metallization of bacteria cells is demonstrated by an electroless deposition technique of nickel-phosphorus initiated by colloid palladium-tin catalyst on the surfaces of Citeromyces matritensis and Bacillus cereus. The activated and metallized bacteria cells have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD). Results showed that both Citeromyces matritensis and Bacillus cereus had no deformation in shape after metallization; the metallized films deposited on the surfaces of bacteria cells are homogeneous in thickness and noncrystalline in phase structure. The kinetics of colloid palladium-tin solution and electroless plating on bacteria cells is discussed.

  11. Poblacion estelar joven embebida en la nube molecular galactica asociada a la fuente IRAS 18236-1205

    Science.gov (United States)

    Romero, Ricardo Retes

    2008-06-01

    En esta tesis presento una metodología de seleccion y estudio de la población estelar embebida en la nube molecular galactica asociada a la fuente IRAS 18236-1205. La fuente IRAS posee colores de region Ultra Compacta HII (UCHII) y tiene deteccióon en monosulfuro de carbono (CS), trazador molecular de alta densidad, lo cual da la posibilidad de definir la nube molecular asociada hacia esta region. Lo anterior muestra que esta es buena candidata a región de formación estelar masiva. La metodología de seleccion de la población embebida, est à basada por una parte, en la distribución del gas molecular monoxido de carbono (13CO) asociado a la fuente IRAS, nube molecular seleccionada del mapeo Galactic Ring Survey (GRS) realizado en 13CO. Otros pasos de la seleccion, se basan en los diagramas color-color y color-magnitud con datos del cercano infrarrrojo de 2MASS. Para el estudio de la componente estelar se usaron los catalogos de fuentes puntuales en el cercano, medio y lejano infrarrojo de 2MASS, SPITZER e IRAS, respectivamente. De los diagramas color-color y color-magnitud, usando datos de 2MASS, se construyo un criterio fotométrico para identificar los objetos estelares j ovenes embebidos en la region molecular. Aplicando modelos a la distribución espectral de energía (SED) de algunos ellos, se encontraron parametros estelares de objetos estelares j ovenes embebidos de masa intermedia y alta. Adicionalmente, se encontro un objeto de masa ´ intermedia no identifiado por el catalogo de 2MASS y su efecto sobre el medio interestelar, emision en la banda de [4.5] μm de IRAC-Spitzer asociado a un outflow. Dos de los objetos seleccionados por el criterio fotometrico resultaron ser objetos estelares jovenes de alta e intermedia masa (B1V/B2V y B8V/A0V respectivamente), los cuales deben estar asociados a la emision radiativa responsable de los colores de región UC HII. Otro objeto estelar joven de baja masa (F0V/F5V) fue encontrado en la region de estudio

  12. Fauna silvestre asociada a ganado vacuno doble propósito en sistema de silvopastoreo, Pinto, Magdalena, Colombia

    Directory of Open Access Journals (Sweden)

    Jaime De La Ossa V.

    2011-12-01

    Full Text Available Objetivo. Evaluar la biodiversidad faunística asociada a ganadería vacuna de doble propósito en dos potreros estructurados con Botriochloa pertusa (colosoana como herbácea dominante, uno de ellos plantado con Crescentia cujete (Bignoniaceae como fuente de alimento adicional y otro con escaso y disperso arbolado. Materiales y métodos. El área de estudio está ubicada en el municipio de Pinto, Magdalena. Cada potrero evaluado fue de 10 ha, se mantuvo en cada uno un lote de quince vacas (½ Cebú, ¼ Pardo y ¼ Costeño con Cuernos, la separación entre las áreas muestreadas fue de 500m. Los registros de fauna se condujeron mediante punto fijo de conteo, en diez sitios de avistamiento, durante 20 días continuos, con cubrimiento visual amplio. Al ganado vacuno adulto presente en las dos áreas de trabajo se le realizó un pesaje individual al inicio del trabajo y al final del mismo, con el fin de determinar posibles diferencias entre ellos. Resultados. Estadísticamente el número de individuos y el número de especies presentaron diferencias significativas, siendo mayor la diversidad biológica para el potrero que poseía la plantación de C. cujete, mientras que el peso corporal de las vacas sometidas a pastoreo en las dos áreas no presentó diferencias significativas. Conclusiones. Se demuestra la importancia de este modelo pecuario como promotor de la conservación faunística local al convertirse enrefugio de variadas especies silvestres, al tiempo que mantiene la productividad existente sin alterar el ambiente sustancialmente.

  13. Nuevas formas de ciudadanía asociadas a las redes de comunicación globales: el ciudadano digital

    Directory of Open Access Journals (Sweden)

    Miguel Pineda Ortega

    2011-04-01

    Full Text Available El objetivo de esta comunicación es indagar acerca de la aparición de la ciudadanía digital, entendida como una nueva forma de ser en el mundo globalizado y conectado mediante las TIC y que se concreta en: el uso eficaz de las redes de comunicación para comunicarse de forma regular, la capacidad de usar Internet para participar como ciudadanos democráticos y la influencia de Internet en la igualdad de derechos. Posteriormente se analiza el fenómeno de las redes sociales, del “fin de semana islámico”, de las ONGs trasnacionales y el desarrollo del software libre como ejemplos de la forma de ser y relacionarse asociada a este fenómeno.Palabras Clave: ciudadanía, globalización, red de comunicación___________________________Abstract:The objective of this paper  is to investigate about the appearance of the digital citizenship phenomenon, understood as a new way to be in the globalised and connected by the TIC world, and which is realized in: the effective use of the net to communicate regularly, the ability  to use Internet to participate as a democratic citizen and the influence of Internet in the equality of rights. Next,  some other phenomenons which I write about are the social networks, the “Islamic weekend”, the transnational NGOs and the development of free software as examples of the way to be and to be related to others.Keywords: citizenship, globalised, Internet

  14. Extracellular communication in bacteria

    DEFF Research Database (Denmark)

    Chhabra, S.R.; Philipp, B.; Eberl, L.;

    2005-01-01

    molecules, in different Gram-positive and Gram-negative bacteria they control pathogenicity, secondary metabolite production, biofilm differentiation, DNA transfer and bioluminescence. The development of biosensors for the detection of these signal molecules has greatly facilitated their subsequent chemical...

  15. Indicator For Pseudomonas Bacteria

    Science.gov (United States)

    Margalit, Ruth

    1990-01-01

    Characteristic protein extracted and detected. Natural protein marker found in Pseudomonas bacteria. Azurin, protein containing copper readily extracted, purified, and used to prepare antibodies. Possible to develop simple, fast, and accurate test for marker carried out in doctor's office.

  16. The fecal bacteria

    Science.gov (United States)

    Sadowsky, Michael J.; Whitman, Richard L.

    2011-01-01

    The Fecal Bacteria offers a balanced, integrated discussion of fecal bacteria and their presence and ecology in the intestinal tract of mammals, in the environment, and in the food supply. This volume covers their use in examining and assessing water quality in order to offer protection from illnesses related to swimming in or ingesting contaminated water, in addition to discussing their use in engineering considerations of water quality, modeling, monitoring, and regulations. Fecal bacteria are additionally used as indicators of contamination of ready-to-eat foods and fresh produce. The intestinal environment, the microbial community structure of the gut microbiota, and the physiology and genomics of this broad group of microorganisms are explored in the book. With contributions from an internationally recognized group of experts, the book integrates medicine, public health, environmental, and microbiological topics in order to provide a unique, holistic understanding of fecal bacteria. Moreover, it shows how the latest basic science and applied research findings are helping to solve problems and develop effective management strategies. For example, readers will discover how the latest tools and molecular approaches have led to our current understanding of fecal bacteria and enabled us to improve human health and water quality. The Fecal Bacteria is recommended for microbiologists, clinicians, animal scientists, engineers, environmental scientists, food safety experts, water quality managers, and students. It will help them better understand fecal bacteria and use their knowledge to protect human and environmental health. They can also apply many of the techniques and molecular tools discussed in this book to the study of a broad range of microorganisms in a variety of habitats.

  17. Evaluación del Riesgo de Acidovorax avenae Subsp. citrulli Asociada a Semilla de Sandía de Importación a México

    OpenAIRE

    Norma Alejandra Elizalde Jiménez; Javier Hernández Morales; Santos Gerardo Leyva Mir; Cristian Nava Díaz; Ronald A. Sequeira; Glenn Fowler; Roger Magarey

    2011-01-01

    Acidovorax avenae subsp. citrulli, causante de la mancha bacteriana del fruto de la sandía, se considera un patógeno con alto potencial de destrucción capaz de causar pérdidas del 100% en vivero o plantación, cuando se desarrolla bajo condiciones ambientales favorables para su multiplicación y diseminación. Por lo anterior, el objetivo de esta investigación fue analizar el riesgo de introducción y establecimiento de A. avenae subsp. citrulli (plaga cuarentenaria para México), asociada a semil...

  18. Paquimeningitis hipertrófica, glomerulonefritis y vasculitis de pequeños vasos asociada a ANCA Hypertrophic pachymeningitis, glomerulonephritis and P-ANCA associated small vessel vasculitis

    OpenAIRE

    Octavio Mazzocchi; Jorge A. Risso; Florencia Viozzi; Natalia P. Apa; Marina C. Peñalba; Miguel A. Nadal; Graciela E. De Rosa

    2007-01-01

    La paquimeningitis hipertrófica es una enfermedad poco frecuente caracterizada por engrosamiento de la duramadre. Presentamos una paciente con esta enfermedad que se manifestó con cefalea crónica y en la que concomitantemente se evidenció una glomerulonefritis necrotizante extracapilar pauciinmune asociada a anticuerpos anticitoplasma de neutrófilos de patrón perinuclear (ANCA-P). El diagnóstico se estableció por resonancia nuclear magnética. Recibió tratamiento inmunosupresor con prednisona ...

  19. Atresia duodenal asociada a invaginación intestinal secundaria a divertículo de meckel en un lactante de tres meses

    OpenAIRE

    Rubén Martín Alvarez-Solís; Fredy Chablé-Montero; Marcela Vargas-Vallejo; David Bulnes Mendizábal; Armando Quero-Hernández; José Cabrera-Aguirre

    2006-01-01

    La asociación entre atresia duodenal e invaginación intestinal no se ha reportado en la literatura. Presentamos las características clínicas y quirúrgicas de un paciente masculino de tres meses de edad que presenta atresia duodenal asociada a invaginación intestinal secundaria a un divertículo de Meckel perforado e invertido. Dentro de las causas de vómitos en lactantes se incluyen las atresias intestinales. Aunque es raro se han reportado casos en otras edades pediátricas. La invaginación in...

  20. Obstáculos del aprendizaje de respiración celular asociada al metabolismo de carbohidratos en estudiantes de nivel universitario

    OpenAIRE

    Garófalo, Judith; Alonso, Manuel

    2009-01-01

    El objetivo del trabajo fue identificar posibles obstáculos en el procesamiento de la información asociada al metabolismo de los carbohidratos y la respiración celular, en estudiantes de segundo año de Ciencias Biológicas de la Universidad de Buenos Aires, mediante una metodología consistente en Entrevistas Concurrentes y Entrevistas Recurrentes.Mostramos que la mayoría de los errores de los estudiantes provienen de visiones parciales y descontextualizadas de los procesos bioquímicos estudiad...

  1. Biomarcadores del estado inflamatorio: nexo de unión con la obesidad y complicaciones asociadas Inflammatory biomarkers: the link between obesity and associated pathologies

    OpenAIRE

    M.ª A. Zulet; B. Puchau; Navarro, C; Martí, A.; J. A. Martínez

    2007-01-01

    El objetivo de este trabajo ha consistido en realizar una revisión de los biomarcadores que actualmente se proponen como el nexo de unión entre la inflamación, la obesidad y complicaciones asociadas, seleccionando los estudios llevados a cabo y las cuestiones pendientes. Cada vez hay mayor evidencia científica de que la inflamación puede jugar un papel importante en la etiología de diversas enfermedades crónicas de gran relevancia para la salud pública. En los últimos años, distintos estudios...

  2. Dermatitis asociada a incontinencia en adultos: un problema sin definición, revisión sistemática

    OpenAIRE

    Renata Virginia González-Consuegra; Lizeth Hasbleidy Mora-Carvajal; Jhonatan Sebastián Celis-Moreno; Gustavo David Matiz-Vera

    2015-01-01

    Antecedentes. La prevalencia de la dermatitis, asociada a incontinencia urinaria, fecal o mixta, está entre 5.6% y 50%, con una tasa de incidencia entre 3.4% y 25%. Estas lesiones infravaloradas no se afrontan adecuadamente por desconocimiento de sus implicaciones y su cuidado, lo que exige conocer la producción científica al respecto, estandarizando estos procesos en personas con riesgo de padecerla. Objetivo. Describir la producción científica disponible que aborde la gestión de los cuidado...

  3. FUENTES DE FOSFATO ASOCIADAS A LA CACHAZA Y EL BIOFERTILIZANTE SOBRE LOS MICROORGANISMOS SOLUBILIZADORES DE FÓSFORO Y SU CONTENIDO EN EL SUELO

    OpenAIRE

    Cid N. Silva Campos; Renato de Mello Prado; Leónides Castellanos González; Maikel Abreu Jiménez; Leandro Rosatto Moda

    2016-01-01

    Los suelos de regiones tropicales presentan una elevada adsorción del fósforo, el cual se encuentra poco disponible para las plantas y limita la producción de los cultivos. Este estudio tuvo como objetivo evaluar el efecto de las fuentes de fosfato acidulado y fosfato natural asociadas a la cachaza, no enriquecida y enriquecida con biofertilizante, sobre la población de microorganismos solubilizadores de fosfatos y los tenores de P en el suelo. El expe...

  4. Gobiernos locales y participación ciudadana: hacia un enfoque de gestión estratégica asociada

    OpenAIRE

    José María Ramos; Marcela Reyes

    2005-01-01

    Se analiza el papel de la gestión local para promover la participación ciudadana, bajo el enfoque de gestión estratégica asociada. El artículo sustenta el argumento de que si bien la participación ciudadana, a través de organizaciones civiles y la sociedad en general, se ha incrementado en las entidades locales y estatales mexicanas, ha tenido dificultades para poder incidir en la gestión y en las políticas de desarrollo. Los temas en donde se desarrolla el argumento son: 1. ...

  5. Eficiencia de uso de nitrógeno en pasturas de Panicum maximum y Brachiaria sp. Solas y asociadas con Pueraria phaseoloides en la altillanura colombiana.

    OpenAIRE

    Pérez López, Otoniel

    2014-01-01

    En la búsqueda de soluciones para mejorar la eficiencia de uso del nitrógeno en praderas de gramíneas forrajeras promisorias de los géneros Panicum y Brachiaria en monocultivo o asociadas con la leguminosa Pueraria phaseoloides como alternativa para la producción sostenible de carne en la Altillanura Colombiana, se desarrolló el presente trabajo de tesis. A través de cinco capítulos aborda en forma detallada aspectos relacionados con la introducción general al análisis de la...

  6. Neumonía asociada a ventilación mecánica : un reto para las unidades de cuidados intensivos

    OpenAIRE

    Calzada Palacios, Laura

    2012-01-01

    Las infecciones nosocomiales (IN) son uno de los problemas de mayor repercusión y transcendencia en los hospitales españoles y especialmente en las unidades de cuidados intensivos (UCI), en donde la neumonía asociada a ventilación mecánica (NAVM) obtiene el primer puesto, entre el resto de IN. El elevado porcentaje de las IN en estas unidades, ha llevado a desarrollar un sistema de vigilancia y control específico. Este incremento de las infecciones en UCI, es debido principalmente al aumento ...

  7. Caracterización de pacientes con bronconeumonía bacteriana asociada a la ventilación artificial mecánica

    OpenAIRE

    Danilo Eranio Utra Cardoso; Leonila Atencio González; Aida Esther Leyva Peña; Gladis Marrero Ávila; Idalia Arcias Castillo

    2015-01-01

    Fundamento: las neumonías nosocomiales constituyen hoy en día un problema de salud a nivel mundial. En las unidades de cuidados intensivos de las instituciones hospitalarias ingresa un elevado número de pacientes que requieren ventilación artificial mecánica, factor de riesgo asociado a este tipo de infecciones. Objetivo: caracterizar a los pacientes con neumonías bacterianas asociadas a la ventilación artificial mecánica, ingresados en la sala de cuidados intensivos del Hospital General D...

  8. Costo de neumonía nosocomial no asociada a ventilación en el hospital universitario de santander, 2007-2009

    OpenAIRE

    2013-01-01

    Objetivo Estimar el exceso de costos asociado a neumonía nosocomial no asociada a ventilación mecánica y las intervenciones clínicas que más influyen en él.Métodos Se realizó un estudio de cohortes pareadas por tiempo de aparición del evento nosocomial. Los expuestos fueron pacientes con neumonía nosocomial y los no expuestos pacientes sin infección nosocomial, con diagnóstico de ingreso similar al expuesto. El principal resultado evaluado en las dos cohortes fueron los costos directos de ate...

  9. Variables psicosociales asociadas al intento suicida, ideación suicida y suicidio en jóvenes

    Directory of Open Access Journals (Sweden)

    Mildred Alexandra Vianchá Pinzón

    2013-01-01

    Full Text Available El objetivo del presente artículo es reflexionar en torno a la relación entre ideación suicida, acto sui - cida, suicidio en jóvenes y variables psicosociales, consideradas por diferentes autores como facto - res de riesgo con base en los estudios realizados durante la última década en español. Para la revi - sión se consultaron las siguientes bases de datos: Dialnet, Redalyc, Scielo y Proquest. A partir de lo anterior se establecieron como predictores: suici - dio, ideación suicida, intento suicida y factores de riesgo. Con respecto a la inclusión de los artículos analizados se tuvo en cuenta que fueran artícu - los empíricos con población joven. Los estudios concentran su atención en la caracterización del fenómeno en los jóvenes latinoamericanos identi - ficando variables psicosociales asociadas como los problemas interpersonales en el contexto escolar, variables psicológicas, las exposición a situaciones de violencia intrafamiliar y abuso sexual, y final - mente los estilos y estrategias de afrontamiento desarrollados por los jóvenes. Se concluye que el suicidio es un fenómeno multicausal (Cabra, In - fante & Sossa, 2010 que va en aumento con la aparición de problemáticas propias de la sociedad actual, tales como el acoso escolar, los trastornos alimentarios, el abuso sexual y el maltrato. Cabe resaltar, que la población más vulnerable a este tipo de problemas siguen siendo los niños y los jó - venes (Barrera, Ordóñez, Palacios & Peña, 2007, lo que exige a los profesionales en salud mental generar estrategias de intervención orientadas a la identificación y prevención de las mismas.

  10. Effective treatment of common variable immunodeficiency associated diarrhea Diarrea asociada a inmunodeficiencia común variable tratada con budesonida

    Directory of Open Access Journals (Sweden)

    H. Córdova Guevara

    2009-03-01

    Full Text Available Common variable immunodeficiency disorder (CVID, the commonest symptomatic primary antibody deficiency syndrome, is characterised by recurrent bacterial infections, particularly of the upper and lower airways; it is also associated with an increased incidence of autoimmune and neoplastic disorders. CVID has a high prevalence of infectious, inflammatory and neoplastic gastrointestinal diseases. Up to 60% of the patients with non-treated CVID develop diarrhea and 10% associated idiopathic malabsorption with weight loss. The case of a 50-year-old woman with CVID-associated diarrhea, abdominal pain and bloating of one year's duration is reported. An exhaustive evaluation made for secondary causes of her symptoms was unrevealing; she was treated with loperamide and diet, without improvement. She later followed a course of oral budesonide for 3 months; her clinical symptoms disappeared and her quality of life improved. In conclusion, we report the case of a patient with CVID-related chronic diarrhea who responded well to oral budesonide treatment. This outcome provides the gastroenterologist with a new therapeutic option in this difficult group of patients.La inmunodeficiencia común variable (IDCV es la deficiencia primaria de anticuerpos sintomática más frecuente y está caracterizada por infecciones bacterianas recurrentes, especialmente de las vías aéreas superiores e inferiores, y también asociada a incremento de enfermedades autoinmunes y neoplasias. Presenta alta prevalencia de enfermedades gastrointestinales infecciosas, inflamatorias y neoplásicas. Hasta el 60% de los pacientes con IDCV no tratados desarrollan diarrea y el 10% desarrollan malabsorción idiopática asociado a pérdida de peso. Presentamos el caso de una mujer de 50 años con IDCV que presenta diarrea crónica, con dolor y distensión abdominal desde hace 1 año. Realizándose múltiples exploraciones y descartando causas secundarias de diarrea crónica, se inicia

  11. La osteonecrosis asociada al tratamiento con bisfosfonatos en osteoporosis primaria: Revisión de la literatura

    Directory of Open Access Journals (Sweden)

    A. Outeiriño-Fernández

    2013-04-01

    Full Text Available Fundamento. El propósito de esta revisión es identificar los factores de riesgo que pueden intervenir en el desarrollo de la osteonecrosis maxilar asociada a bisfosfonatos (OMB tras cirugía oral, en pacientes en tratamiento con bisfosfonatos (BP por osteoporosis primaria. Material y métodos. Con el fin de localizar las publicaciones de relevancia se llevó a cabo una búsqueda en bases de datos tanto de ámbito especializado, como general. La estrategia de búsqueda empleada fue osteonecrosis, bisfosfonatos y cirugía oral. Ésta fue limitada a estudios publicados desde el año 2006 a enero de 2012, en inglés y español realizados en humanos, adultos, tratados con bisfosfonatos por osteoporosis primaria y sometidos a cirugía dentoalveolar. Fueron incluidas revisiones sistemáticas, meta-análisis, guías de práctica clínica, ensayos clínicos aleatorizados y series de casos. Resultados. Se seleccionaron un total de 14 artículos (series de casos, que recogían un total de 43 casos de OMB. La mandíbula y la exodoncia fueron la localización y procedimiento odontológico más frecuente en relación con las lesiones descritas. La media de edad de los pacientes fue de 71,94 años, con predilección por el sexo femenino. El alendronato fue el fármaco empleado en la mayoría de los casos y la duración media de tratamiento previa a la aparición de OMB fue de 48,25 meses. Conclusiones. Son necesarios más estudios prospectivos y retrospectivos con un diseño adecuado para evaluar el peso real de cada uno de los factores considerados de riesgo para el desarrollo de la OMB.

  12. Infección natural de chinches Triatominae con Trypanosoma cruzi asociadas a la vivienda humana en México

    Directory of Open Access Journals (Sweden)

    Vidal-Acosta Vianey

    2000-01-01

    Full Text Available OBJETIVO: Informar el porcentaje de infección natural de las especies de triatóminos que habitan con mayor frecuencia el medio doméstico y peridoméstico en México, así como dar a conocer las localidades de colecta por estado. MATERIAL Y MÉTODOS: Se recibieron muestras de chinches Triatominae en el Departamento de Entomología del Instituto de Diagnóstico y Referencia Epidemiológicos, para su determinación taxonómica y la búsqueda parasitoscópica de Trypanosoma cruzi, provenientes de 14 estados del país, de enero de 1993 a diciembre de 1999. Se analizaron en conjunto los resultados obtenidos en esos años. RESULTADOS: De una muestra de 5 399 ejemplares, fueron 13 las especies de triatóminos asociadas a las viviendas. El porcentaje de infección natural tuvo una amplia variación entre las especies. De las estudiadas, nueve se encontraron con infección natural; el mayor porcentaje de infección corresponde a Triatoma pallidipennis, T. picturata, Rhodnius prolixus y T. longipennis. Los estados con mayor porcentaje de infección fueron Nayarit, Morelos y Michoacán. Se presentaron nuevos registros estatales de Triatoma dimidiata, T. gerstaeckeri, T. longipennis, T. mexicana y T. pallidipennis y uno local de Pastrongylus rufotuberculatus. Además, se informa por primera vez la infección natural en algunas de ellas. CONCLUSIONES: Se debe poner mayor énfasis en el estudio de la biología y aspectos bionómicos de los triatóminos y realizar una vigilancia permanente para tener los registros de distribución actualizados, así como para conocer los índices de infección natural por T. cruzi, de las especies domiciliarias, peridomiciliarias y de las que están en proceso de adaptación a la vivienda humana.

  13. TOXICODERMIA ASOCIADA A BENDAMUSTINA

    Directory of Open Access Journals (Sweden)

    Valdivia I

    2014-05-01

    Full Text Available Bendamustine is a cytotoxic drug used in the treatment of Chronic Lymphocytic Leukemia can cause various adverse skin reactions. We report the case of a woman who received Bendamustine and developed a skin rash

  14. Anaerobic bacteria in otitis media.

    Science.gov (United States)

    Fulghum, R S; Daniel, H J; Yarborough, J G

    1977-01-01

    Anaerobic bacteria, Peptostrepotococcus intermedius and Propionibacterium acnes, were found in mixed culture specimens from four to ten tested cases of chronic secretory otitis media. These anaerobic bacteria were in a mixed infection flora with aerobic bacteria most often Staphylococcus epidermidis and Cornybacterium sp. which do not fit any established species. The findings of anaerobic bacteria in otitis media is consistent with the sporadic report of the involvement of anaerobic bacteria in otitis media in the literature since 1898.

  15. Especies mexicanas de Curculionidae (Insecta: Coleoptera asociadas con agaves (Asparagaceae: Agavoideae Mexican species of Curculionidae (Insecta: Coleoptera associated to agaves (Asparagaceae: Agavoideae

    Directory of Open Access Journals (Sweden)

    Alberto Romo

    2012-12-01

    Full Text Available Se estudiaron las especies de picudos o gorgojos (Coleoptera: Curculionidae asociadas con agaves (Asparagaceae: Agavoideae en México. Se registraron 5 especies asociadas con especies de Agave, Furcraea, Hesperoyucca, Polianthes y Yucca; de éstas, 4 pertenecen a la subfamilia Dryophthorinae (Scyphophorus acupunctatus, S. yuccae, Rhinostomus frontalis y Cactophagus spinolae y 1 a la Baridinae (Peltophorus polymitus. Se presentan diagnosis, ilustraciones y una clave para la identificación de las 5 especies de curculiónidos asociados con agaves. Se establecen las siguientes sinonimias: Sphenophorus validus LeConte, 1858 = Cactophagus spinolae (Gyllenhal, 1838; y Zygops polymitus seminiveus LeConte, 1884, Z. p. leopardinus Desbrochers, 1891 y Z. p. suffusus Casey, 1892 = Peltophorus polymitus Boheman, 1845.Weevils (Coleoptera: Curculionidae associated with agaves (Asparagaceae: Agavoideae from Mexico are analyzed. Five species were recorded associated with species of Agave, Furcraea, Hesperoyucca, Polianthes, and Yucca. Four of these species belong to the subfamily Dryophthorinae (Scyphophorus acupunctatus, S. yuccae, Rhinostomus frontalis, and Cactophagus spinolae and 1 belongs to the subfamily Baridinae (Peltophorus polymitus. Diagnoses, illustrations and a key are presented for identifying the 5 species of weevils found on agaves. The following synonymies are established: Sphenophorus validus LeConte, 1858 = Cactophagus spinolae (Gyllenhal, 1838; and Zygops polymitus seminiveus LeConte, 1884, Z. p. leopardinus Desbrochers, 1891, and Z. p. suffusus Casey, 1892 = Peltophorus polymitus Boheman, 1845.

  16. Congenital lumbar hernia associated to lumbar costovertebral syndrome. A case report. Hernia lumbar congénita asociada a síndrome lumbocostovertebral. Reporte de un caso.

    Directory of Open Access Journals (Sweden)

    Yusimy Izaguirre Martínez

    2005-12-01

    Full Text Available Reported the case of a born patient of color of white skin, 6 years old, of pregnancy and normal childbirth that it was valued in the Service of Surgery of the Pediatric Hospital ¨Paquito González Cueto¨ because it presented increase of volume in both lumbar regions, without another associate sintomatology. Congenital bilateral lumbar hernia associated to syndrome lumbocostovertebral, strange affection in the pediatric age.

    Se reporta el caso de una paciente de color de piel blanca, de 6 años de edad, nacida de embarazo y parto normal que fue valorada en el Servicio de Cirugía del Hospital Pediátrico ¨Paquito González Cueto¨ debido a que presentaba aumento de volumen en ambas regiones lumbares, sin otra sintomatología asociada. Se diagnostica hernia lumbar bilateral congénita asociada a síndrome lumbocostovertebral, afección rara en la edad pediátrica.

  17. Mycophagous soil bacteria

    NARCIS (Netherlands)

    Rudnick, M.B.

    2015-01-01

    Abstract

    Soil microorganisms evolved several strategies to compete for limited nutrients in soil. Bacteria of the genus Collimonas developed a way to exploit fungi as a source of organic nutrients. This strategy has been termed “mycophagy&r

  18. PRODUCCIÓN DE ENZIMAS EXTRACELLARES POR BACTERIAS AISLADAS DE INVERTEBRADOS MARINOS

    Directory of Open Access Journals (Sweden)

    Jorge León

    2014-06-01

    Full Text Available Con el fin de seleccionar las bacterias marinas con la capacidad de producir enzimas extracelulares ( CEE , se analizaron muestras de Argopecten purpuratus y Crassostrea gigas en el cultivo , así como de otros invertebrados interticlal y bentónicos. La selección de cepas de la CEE de productores se llevó a cabo en Agar Marino ( MA con la adición del sustrato relevante ( almidón , caseína , Tween - 80 , lecitina , ADN y gelatina . La CEE evaluación cepas productoras se llevó a cabo en 102 aislamientos . Los resultados muestran que las bacterias asociadas TOA . purpuratusand C. gigashave las mejores actividades multienzimáticos ; Sin embargo , Semimytilus algosus, Tetrapigus niger y Thais chocolata también son fuentes importantes de productores de bacterias de la CEE. La actividad multienzimático cualitativa en MA ( zonas claras u opacas alrededor de las colonias en mm de diámetro varió de 6 a > 16 mm . La frecuencia de la producción multienzimático fue caseinase 62,74 % , entre esterasa 57,84 % , 52,94 % de la amilasa , la gelatinasa 38,23 % , 33,3 % DNAsa , agarasa 5,43 % y 90,0 % lecitinasa . Los resultados sugieren la posibilidad de usar cepas nativas para fines biotecnológicos

  19. Hemorragias intracraneales de carácter evitable asociadas a anticoagulantes orales en pacientes con fibrilación auricular Avoidable intracranial hemorrhages associated with oral anticoagulants in patients with atrial fibrillation

    OpenAIRE

    A. García Luque; J. Torello Iserte; J.R. Castillo Ferrando

    2011-01-01

    Introducción y objetivo: El aumento de la prescripción de anticoagulantes orales ha provocado un aumento de hemorragias intracraneales, la reacción adversa más grave asociada a este grupo farmacológico. El objetivo del estudio es evaluar el carácter evitable de hemorragias intracraneales asociada a anticoagulantes orales que causan ingreso hospitalario en pacientes con fibrilación auricular. Método: Supervisión de las historias clínicas de los pacientes que ingresaron en los Hospitales Univer...

  20. Acciones de enfermería para la prevención de la neumonía asociada a ventilación mecánica: revisión sistemática

    OpenAIRE

    Kluczynik Vieira, Caroline Evelin Nascimento; de Andrade, Paula Stefânia; Enders, Bertha Cruz; Coura, Alexsandro Silva; Dutra, Michelinne Oliveira Machado

    2014-01-01

    Objetivo: Identificar acciones de enfermería implementadas en la prevención de la neumonía asociada a ventilación mecánica en los pacientes intubados en la Unidad de Cuidados Intensivos. Método: Revisión sistemática en las bases: PubMed, BVS y Scielo utilizando los descriptores: "Atención de Enfermería" y "Neumonía Asociada al Ventilador". La muestra constaba de 13 artículos. La calidad interna se evaluó mediante la clasificación de Jadad. Resultados: Los destaqu...

  1. Hepatotoxicity associated with the ingestion of Centella asiatica Hepatotoxicidad asociada al consumo de Centella asiática

    Directory of Open Access Journals (Sweden)

    O. A. Jorge

    2005-02-01

    presentaron ictericia después de consumir Centella asiática por 30, 20 y 60 días. Analíticas respectivas: ALT: 1193, 1694 y 324 U/l; FAL: 503, 472 y 484 U/l; bilirrubina: 4,23, 19,89 y 3,9 mg/dl. La primera presentó ASMA 1/160 y AMA 1/320. Diagnósticos anatomopatológicos: respectivamente hepatitis granulomatosa con marcada necrosis y apoptosis; hepatitis crónica con transformación cirrótica e intensa actividad necroinflamatoria y hepatitis granulomatosa. Todas mejoraron al suspender Centella asiática y con ácido ursodeoxicólico 10 mg/kg/día. La primera volvió a ingerir Centella asiática, repitiendo las lesiones. La segunda había ingerido esta sustancia un año antes. Conclusiones: muchos vegetales sintetizan compuestos hepatotóxicos. Camedrio, escutelaria y glicirricina poseen principios activos di- o triterpénicos que pueden lesionar el hígado promoviendo apoptosis y alterando membranas celulares. Hipotetizamos que estos mecanismos pueden haber producido las lesiones asociadas a Centella asiática. La presencia de autoanticuerpos y granulomas también favorecen un mecanismo inmunológico. El ácido ursodeoxicólico posee propiedades antiapoptóticas, aunque no podemos descartar que la sola discontinuación de Centella asiática haya determinado la mejoría de las pacientes.

  2. Can bacteria save the planet?

    OpenAIRE

    Hunter, Philip

    2010-01-01

    Bacteria might just hold the key to preserving the environment for our great grandchildren. Philip Hunter explores some of the novel ways in which systems biology and biotechnology are harnessing bacteria to produce renewable energy and clean up pollution.

  3. Manufacture of Probiotic Bacteria

    Science.gov (United States)

    Muller, J. A.; Ross, R. P.; Fitzgerald, G. F.; Stanton, C.

    Lactic acid bacteria (LAB) have been used for many years as natural biopreservatives in fermented foods. A small group of LAB are also believed to have beneficial health effects on the host, so called probiotic bacteria. Probiotics have emerged from the niche industry from Asia into European and American markets. Functional foods are one of the fastest growing markets today, with estimated growth to 20 billion dollars worldwide by 2010 (GIA, 2008). The increasing demand for probiotics and the new food markets where probiotics are introduced, challenges the industry to produce high quantities of probiotic cultures in a viable and stable form. Dried concentrated probiotic cultures are the most convenient form for incorporation into functional foods, given the ease of storage, handling and transport, especially for shelf-stable functional products. This chapter will discuss various aspects of the challenges associated with the manufacturing of probiotic cultures.

  4. Lipoprotein sorting in bacteria.

    Science.gov (United States)

    Okuda, Suguru; Tokuda, Hajime

    2011-01-01

    Bacterial lipoproteins are synthesized as precursors in the cytoplasm and processed into mature forms on the cytoplasmic membrane. A lipid moiety attached to the N terminus anchors these proteins to the membrane surface. Many bacteria are predicted to express more than 100 lipoproteins, which play diverse functions on the cell surface. The Lol system, composed of five proteins, catalyzes the localization of Escherichia coli lipoproteins to the outer membrane. Some lipoproteins play vital roles in the sorting of other lipoproteins, lipopolysaccharides, and β-barrel proteins to the outer membrane. On the basis of results from biochemical, genetic, and structural studies, we discuss the biogenesis of lipoproteins in bacteria, their importance in cellular functions, and the molecular mechanisms underlying efficient sorting of hydrophobic lipoproteins to the outer membrane through the hydrophilic periplasm. PMID:21663440

  5. Exopolysaccharides from Marine Bacteria

    Institute of Scientific and Technical Information of China (English)

    CHI Zhenming; FANG Yan

    2005-01-01

    Microbial polysaccharides represent a class of important products of growing interest for many sectors of industry. In recent years, there has been a growing interest in isolating new exopolysaccharides (EPSs)-producing bacteria from marine environments, particularly from various extreme marine environments. Many new marine microbial EPSs with novel chemical compositions, properties and structures have been found to have potential applications in fields such as adhesives,textiles, pharmaceuticals and medicine for anti-cancer, food additives, oil recovery and metal removal in mining and industrial waste treatments, etc This paper gives a brief summary of the information about the EPSs produced by marine bacteria,including their chemical compositions, properties and structures, together with their potential applications in industry.

  6. Estudio de la influencia microbiológica en la corrosión de latones (UNS C68700, UNS C443 y acero inoxidable AISI 316;

    Directory of Open Access Journals (Sweden)

    Ohanian, Mauricio

    2014-06-01

    Full Text Available Microorganisms may play an important role in the corrosion process and generate conditions which affect the rate and/or the mechanism of deterioration. They become visible by the formation of biofilms: clusters of microorganisms and extracellular polymers. These biofilms affect not only the durability of the material, but also reduce the heat transfer. The present work studied the growth of aerobic and anaerobic heterotrophic microorganisms and sulfate reducing bacteria on aluminum brass (UNS C68700, admiralty brass (UNS C443 and stainless steel AISI 316 in exposure experiments held in the Bay of Montevideo (Uruguay. The influence of the biofilm growth on the corrosion behavior was studied by electrochemical techniques: polarization curves and Electrochemical Impedance Spectroscopy (EIS. The selection of the most suitable material for the exposure conditions is discussed and hypotheses of the corrosion mechanism are presented. Although stainless steel AISI 316 presented the lowest corrosion rate it showed localized deterioration.Los microorganismos influyen de manera significativa en el proceso corrosivo y generan condiciones que afectan la velocidad y/o el mecanismo de deterioro. Su presencia se manifiesta por la formación de bio-películas: conglomerados de bacterias y polímeros extracelulares. Dichas bio-películas afectan la durabilidad del material, la velocidad de flujo y la transferencia de calor. En el presente trabajo se evalúa el crecimiento de microorganismos heterótrofos aerobios, heterótrofos anaerobios y bacterias sulfato-reductoras sobre latón aluminio (UNS C68700, latón almirantazgo (UNS C443 y acero inoxidable AISI 316. Asimismo, se estudia la influencia del crecimiento de la bio-película sobre el comportamiento corrosivo mediante técnicas electroquímicas: curvas de polarización y espectroscopia de impedancia electroquímica. Las exposiciones se realizan en la Bahía de Montevideo, estuario del Río de la Plata

  7. Estudio de la microbiota asociada al proceso de fermentación de las aceitunas arbequinas de mesa

    OpenAIRE

    Hurtado Fernández-Anchuela, Albert

    2010-01-01

    En esta tesis se ha caracterizado a nivel de especie la ecología del proceso de fermentación industrial de las aceitunas de mesa arbequinas. Los resultados muestran que se establece un equilibrio dinámico entre bacterias lácticas y levaduras. También existe inicialmente un importante número de enterobacterias que desaparecen conforme el pH del medio baja. Lactobacillus pentosus, Candida diddensiae y Candida boidinii han sido las principales especies identificadas. También se ha estudiado a es...

  8. Dermatitis asociada a incontinencia en adultos: un problema sin definición, revisión sistemática

    Directory of Open Access Journals (Sweden)

    Renata Virginia González-Consuegra

    2015-04-01

    Full Text Available Antecedentes. La prevalencia de la dermatitis, asociada a incontinencia urinaria, fecal o mixta, está entre 5.6% y 50%, con una tasa de incidencia entre 3.4% y 25%. Estas lesiones infravaloradas no se afrontan adecuadamente por desconocimiento de sus implicaciones y su cuidado, lo que exige conocer la producción científica al respecto, estandarizando estos procesos en personas con riesgo de padecerla. Objetivo. Describir la producción científica disponible que aborde la gestión de los cuidados de las personas adultos mayores que presentan dermatitis asociada a incontinencia urinaria, fecal o mixta. Materiales y métodos. Se llevó a cabo una revisión sistemática de literatura científica en las bases de datos Ovid Nursing, SciELO, Biblioteca Virtual en Salud, Pubmed, Scopus, EBSCOhost, ScienceDirect, Cuiden, JSTOR y Springer Journal, sin fecha límite, en cualquier idioma. Se valoraron los artículos mediante el sistema GRADE. Resultados. Se encontraron 45 artículos, en su mayoría de Norteamérica y Europa, de los cuales un 15.22% abordan temas de epidemiología, 15.22% tratan sobre factores de riesgo, 32.61% sobre prevención primaria, 8.70% sobre diagnóstico, 17.39%, tratamiento, 4.35%, medición del problema y 6.52%, rehabilitación. La metodología en el 53% de los artículos correspondió a ensayos clínicos. Conclusión. La toma de decisiones con respecto al diagnóstico, la prevención y el tratamiento de la dermatitis asociada a incontinencia, deben apoyarse en los múltiples factores de riesgo y etiológicos de las lesiones de piel que puedan tener relación con la dependencia, los cuales, sin lugar a dudas, orientarán el mecanismo de producción y así, laintervención de la enfermedad.

  9. Pepsin homologues in bacteria

    Directory of Open Access Journals (Sweden)

    Bateman Alex

    2009-09-01

    Full Text Available Abstract Background Peptidase family A1, to which pepsin belongs, had been assumed to be restricted to eukaryotes. The tertiary structure of pepsin shows two lobes with similar folds and it has been suggested that the gene has arisen from an ancient duplication and fusion event. The only sequence similarity between the lobes is restricted to the motif around the active site aspartate and a hydrophobic-hydrophobic-Gly motif. Together, these contribute to an essential structural feature known as a psi-loop. There is one such psi-loop in each lobe, and so each lobe presents an active Asp. The human immunodeficiency virus peptidase, retropepsin, from peptidase family A2 also has a similar fold but consists of one lobe only and has to dimerize to be active. All known members of family A1 show the bilobed structure, but it is unclear if the ancestor of family A1 was similar to an A2 peptidase, or if the ancestral retropepsin was derived from a half-pepsin gene. The presence of a pepsin homologue in a prokaryote might give insights into the evolution of the pepsin family. Results Homologues of the aspartic peptidase pepsin have been found in the completed genomic sequences from seven species of bacteria. The bacterial homologues, unlike those from eukaryotes, do not possess signal peptides, and would therefore be intracellular acting at neutral pH. The bacterial homologues have Thr218 replaced by Asp, a change which in renin has been shown to confer activity at neutral pH. No pepsin homologues could be detected in any archaean genome. Conclusion The peptidase family A1 is found in some species of bacteria as well as eukaryotes. The bacterial homologues fall into two groups, one from oceanic bacteria and one from plant symbionts. The bacterial homologues are all predicted to be intracellular proteins, unlike the eukaryotic enzymes. The bacterial homologues are bilobed like pepsin, implying that if no horizontal gene transfer has occurred the duplication

  10. Diseño de intervención ante una de las problemáticas asociadas al Absentismo Escolar: la falta de motivación escolar

    OpenAIRE

    Armesto Arias, Marta

    2014-01-01

    Diseño de intervención con tres colectivos (padres y madres, alumnos y alumnas y profesorado), ante una de las problemáticas asociadas al Absentismo Escolar en la ciudad de Gijón como es la falta de motivación escolar.

  11. Explotación de peces asociada a la pesquería artesanal de langosta de Juan Fernández (Jasus frontalis

    Directory of Open Access Journals (Sweden)

    Mauricio Ahumada

    2014-03-01

    Full Text Available Para contribuir al conocimiento de la explotación de peces asociada a la pesquería de langosta de Juan Fernández, se monitorearon 157 salidas de pesca durante la temporada 2010-2011. Se capturaron 10.462 ejemplares correspondientes a 19 especies de peces, tres de las cuales concentraron el 94% de la captura en número: jurel de Juan Fernández (Pseudocaranx chilensis (45%, breca (Nemadactylus gayi (41% y anguila morena (Gymnothoraxporphyreus (8%. Las capturas totales estimadas fueron 40, 24 y 13 ton de breca, jurel de Juan Fernández y anguila morena, respectivamente. El 97% de los ejemplares de peces capturados fueron utilizados como carnada de peces o langosta.

  12. Lesiones cutáneas asociadas a leucemia Infantil: Presentación de dos casos Cutaneous Lesions Associated with Pediatric Leukemia: Report of 2 Clinical Cases

    Directory of Open Access Journals (Sweden)

    Alejandra Acosta-Gualandri

    2011-01-01

    Full Text Available La leucemia cutánea es una patología extremadamente infrecuente y se puede presentar en diferentes tipos de leucemias, asociada o no a síndromes genéticos. Es una forma muy poco común de presentación inicial de malignidad, por lo que es importante reportar dos casos atendidos en el HNN.Cutaneous leukemia is an extremely uncommon condition, and it can be seen in different types of leukemias, associated or not to genetic syndromes. It is an uncommon form of presentation of malignancies, so it is important to report 2 cases seen and treated at the National Children’s Hospital.

  13. Guía para la valoración multiaxial del "esguince cervical" y la patología discal asociada

    Directory of Open Access Journals (Sweden)

    J. Aso Escario

    2014-03-01

    Full Text Available Se aporta un enfoque de la valoración del esguince cervical basado en un modelo multidimensional. A modo de checklist se consideran aspectos relativos al accidente, las lesiones cervicales, el estado anterior, las lesiones extracervicales y aspectos psicológicos, incluyendo la simulación. Ya que el esguince cervical es no sólo, ni a veces principalmente, un cuadro médico, sino derivado de factores no médicos, se considera este modelo multiaxial como la mejor manera de abordar su valoración y tratamiento. Se insiste en la necesidad de valorar pericialmente las pruebas complementarias, en la importancia de algunas patologías asociadas y en la utilidad de un lenguaje común al hablar de la simulación o la exageración.

  14. ESPECIES DE DRYOPHTHORINAE (COLEOPTERA: CURCULIONIDAE ASOCIADAS A PLÁTANO Y BANANO (Musaspp. EN COLOMBIA Dryophthorinae Species (Coleoptera: Curculionidae Associted to Platain and Banana crops (Musaspp. in Colombia

    Directory of Open Access Journals (Sweden)

    PAULA A SEPÚLVEDA-CANO

    Full Text Available Se presenta una sinopsis de los escarabajos de la subfamilia Dryophthorinae (Coleoptera: Curculionidae asociados a cultivos de plátano y banano en Colombia. Adicionalmente se ofrecen claves ilustradas para las especies del país. Se registran seis especies asociadas a dichos cultivos: Cosmopolites sordidus (Germar, 1824, Metamasius hemipterus (Linnaeus, 1758, Metamasius hebetatus (Gyllenhal, 1838, Metamasius submaculatus Champion, 1910, Rhyncophorus palmarum (Linnaeus, 1758 y Polytus mellerborgii (Boheman, 1838.This synopsis is about beetle&#’;s subfamily Dryophthorinae (Coleoptera: Curculionidae associated to plantain and banana crops. Additionally keys illustrated for the species of the country are offered. Six species associated to these cultures are registered: Cosmopolites sordidus (Germar, 1824, Metamasius hemipterus (Linnaeus, 1758, Metamasius hebetatus (Gyllenhal, 1838, Metamasius submaculatus Champion, 1910, Rhyncophorus palmarum (Linnaeus, 1758 y Polytus mellerborgii (Boheman, 1838.

  15. Susceptibilidad genética a desarrollar Cáncer de pulmón asociada con el gen polimórfico hidrolasa epoxida

    Directory of Open Access Journals (Sweden)

    Sierra CH.

    2001-06-01

    Full Text Available La enzima metabólica hidrolasa epóxida microsomal (mHE está involucrada en biotransforma-ción de carcinógenos del cigarrillo (ej., benzo-a-pireno. Este estudio investigó la susceptibilidad genética a desarrollar cáncer de pulmón asociada con los polimorfismos en los exones 3 y 4 delgen mHE, los cuales confieren reducida e incrementada actividad enzimática respectivamente. Además, se determinó su efecto en la frecuencia de aberraciones cromosómicas (AC como unamedida adicional de riesgo. La población de estudio incluyó 110 pacientes con cáncer de pulmóny 119 fumadores saludables.

  16. Aislamiento, selección y caracterización de una bacteria ácido láctica porcina como probiótico en lechones post destete

    OpenAIRE

    Rebolledo Londoño, Ángelo

    2014-01-01

    Con el objetivo de identificar y caracterizar bacterias acido lácticas BAL de origen porcino asociadas al estado de sanidad intestinal de los lechones posdestete, se llevó a cabo un experimento donde se aislaron 38 cepas de BAL para evaluar su potencial de colonización del tracto gastrointestinal a través de la prueba de in vitro de adhesión y aglutinación a mannosa. Se seleccionó la BAL L605 y se evaluó su capacidad para fermentar alimentos balanceados basados en maíz y soya, utilizados en l...

  17. Identificación y clasificación en biotipos de las malezas asociadas con el cultivo de la palma de aceite

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Ariza

    2012-07-01

    Full Text Available En dos plantaciones de palma de aceite, ubicadas en los municipios de Villanueva, Casanare, y Barranca de Upía, Meta, (Colombia, zona del Bajo Upía, se realizó un reconocimiento y clasificación en biotipos de las malezas asociadas con la palma de aceite. Para realizar el trabajo se visitaron las dos fincas, y se procedió a recoger muestras y fotografiar las malezas que se encontraban dentro del cultivo, así como en su contorno. La identificación y descripción se realizó siguiendo la metodología binaria latina expuesta por Linneo y especificada en el Código Internacional de Nomenclatura Botánica, reportada para las especies reconocidas, mediante los servicios del herbario de la Universidad Pedagógica y Tecnológica de Colombia, y referencias de autores como Doll et al. (1972, Lemus y Lemus (2004, Rentería et al. (2006, Blair y Madrigal (2005, Fuentes et al. (1998, Kress et al. (2004, Becerra y Chaparro (1999 y Genty (1993. Para la agrupación de las malezas en biotipos (lianas, herbáceas, arbustos y árboles se tuvieron en cuenta sus características morfológicas. Se encontraron en  total 195 especies de malezas asociadas con el cultivo de la palma de aceite, 145 dicotiledóneas y 50 monocotiledóneas, pertenecientes a 43 familias.

  18. Características asociadas al subregistro de muerte en niños del estado de Guerrero, México

    Directory of Open Access Journals (Sweden)

    TOMÉ PATRICIA

    1997-01-01

    Full Text Available Objetivo. Estimar la frecuencia de subregistro de muerte en niños en localidades rurales e identificar las características asociadas. Material y métodos. El estudio se realizó en tres etapas: en la primera se formaron tres estratos de localidades según el número de habitantes; de cada estrato se eligió, de manera aleatoria, un número representativo de localidades que fueron censadas para identificar las defunciones ocurridas entre junio de 1993 y julio de 1994. En la segunda etapa se realizó autopsia verbal con las madres de los niños fallecidos para identificar la causa de muerte e investigar las variables de estudio. Por último, se identificó el registro de muerte a través de los certificados de defunción. Resultados. Se identificó una frecuencia de subregistro de 68.9%; en las localidades menores de 500 habitantes fue de 73.2%, y en las mayores, de 60.5%. Como características asociadas al subregistro se identificaron: carecer de certificado de defunción y de registro de nacimiento; edad menor de un mes; desconocimiento del concepto y funciones del registro civil; distancia al registro civil y acceso al médico mayor de 30 minutos, y localidad menor de 1 000 habitantes. Conclusiones. Se propone una modificación en la organización actual del procedimiento de registro de muerte, así como el establecimiento del certificado de nacimiento propuesto por el Sistema Nacional de Salud.

  19. Dinámica microbial del suelo asociada a diferentes estrategias de manejo de Phytophthora cinnamomi Rands en aguacate

    Directory of Open Access Journals (Sweden)

    Joaquín Guillermo Ramírez Gil

    2013-12-01

    Full Text Available La marchitez del aguacate es la enfermedad más limitante de este cultivo, cuyo agente causal más relevante es el oomycete Phytophthora cinnamomi Rands. Es por esto que se han desarrollado diferentes estrategias para su manejo integrado, pero aún prevalece el uso de productos químicos, como única medida de manejo, generando impactos negativos en el ambiente y la salud. Uno de los efectos perjudiciales que se ocasiona es la alteración de las poblaciones microbianas en el suelo. Este trabajo estuvo encaminado a conocer la dinámica microbiana del suelo, bajo diferentes estrategias de manejo de esta enfermedad, para lo cual se midió su dinamismo mediante unidades formadoras de colonias (UFC, para hongos, bacterias y actinomicetos, a partir de muestras de suelo y rizósfera de la raíz, bajo incubación en condiciones de anaerobiosis y aerobiosis, además se midió la actividad microbiana total, en condiciones de laboratorio, como complemento se cuantificaron microorganismos como: Trichiderma spp, bacterias formadoras de endosporas (BAFE, celulolíticos, proteolíticos, amilolíticos, solubilizadores de fosfato, fijadores asimbióticos de nitrógeno y promotores del crecimiento, como Pseudomonas spp., fluorescentes. Los resultados encontrados en esta investigación, sugieren que el uso individual y combinado de mantillo orgánico, material compostado de estiércol bovino, enmienda mineral y cascarilla de arroz y la propuesta de integración; incrementan significativamente la población y actividad microbiana aerobia, en la cual se identificaron microorganismos antagonistas como, Trichiderma spp., celulolíticos, Pseudomonas spp. fluorescentes y BAFE.

  20. Nitrogen control in bacteria.

    Science.gov (United States)

    Merrick, M J; Edwards, R A

    1995-12-01

    Nitrogen metabolism in prokaryotes involves the coordinated expression of a large number of enzymes concerned with both utilization of extracellular nitrogen sources and intracellular biosynthesis of nitrogen-containing compounds. The control of this expression is determined by the availability of fixed nitrogen to the cell and is effected by complex regulatory networks involving regulation at both the transcriptional and posttranslational levels. While the most detailed studies to date have been carried out with enteric bacteria, there is a considerable body of evidence to show that the nitrogen regulation (ntr) systems described in the enterics extend to many other genera. Furthermore, as the range of bacteria in which the phenomenon of nitrogen control is examined is being extended, new regulatory mechanisms are also being discovered. In this review, we have attempted to summarize recent research in prokaryotic nitrogen control; to show the ubiquity of the ntr system, at least in gram-negative organisms; and to identify those areas and groups of organisms about which there is much still to learn. PMID:8531888

  1. Chemical communication in bacteria

    Science.gov (United States)

    Suravajhala, Srinivasa Sandeep; Saini, Deepak; Nott, Prabhu

    Luminescence in Vibrio fischeri is a model for quorum-sensing-gene-regulation in bacteria. We study luminescence response of V. fischeri to both internal and external cues at the single cell and population level. Experiments with ES114, a wild-type strain, and ainS mutant show that luminescence induction in cultures is not always proportional to cell-density and there is always a basal level of luminescence. At any given concentration of the exogenously added signals, C6-HSL and C8-HSL, luminescence per cell reaches a maximum during the exponential phase and decreases thereafter. We hypothesize that (1) C6-HSL production and LuxR activity are not proportional to cell-density, and (2) there is a shift in equilibrium from C6-HSL to C8-HSL during the later stages of growth of the culture. RT-PCR analysis of luxI and luxR shows that the expression of these genes is maximum corresponding to the highest level of luminescence. The shift in equilibrium is shown by studying competitive binding of C6-HSL and C8-HSL to LuxR. We argue that luminescence is a unicellular behaviour, and an intensive property like per cell luminescence is more important than gross luminescence of the population in understanding response of bacteria to chemical signalling. Funding from the Department of Science and Technology, India is acknowledged.

  2. Beneficial bacteria inhibit cachexia.

    Science.gov (United States)

    Varian, Bernard J; Goureshetti, Sravya; Poutahidis, Theofilos; Lakritz, Jessica R; Levkovich, Tatiana; Kwok, Caitlin; Teliousis, Konstantinos; Ibrahim, Yassin M; Mirabal, Sheyla; Erdman, Susan E

    2016-03-15

    Muscle wasting, known as cachexia, is a debilitating condition associated with chronic inflammation such as during cancer. Beneficial microbes have been shown to optimize systemic inflammatory tone during good health; however, interactions between microbes and host immunity in the context of cachexia are incompletely understood. Here we use mouse models to test roles for bacteria in muscle wasting syndromes. We find that feeding of a human commensal microbe, Lactobacillus reuteri, to mice is sufficient to lower systemic indices of inflammation and inhibit cachexia. Further, the microbial muscle-building phenomenon extends to normal aging as wild type animals exhibited increased growth hormone levels and up-regulation of transcription factor Forkhead Box N1 [FoxN1] associated with thymus gland retention and longevity. Interestingly, mice with a defective FoxN1 gene (athymic nude) fail to inhibit sarcopenia after L. reuteri therapy, indicating a FoxN1-mediated mechanism. In conclusion, symbiotic bacteria may serve to stimulate FoxN1 and thymic functions that regulate inflammation, offering possible alternatives for cachexia prevention and novel insights into roles for microbiota in mammalian ontogeny and phylogeny. PMID:26933816

  3. Immunomodulatory properties of probiotic bacteria

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen

    2007-01-01

    Certain lactic acid bacteria (LAB) are part of the commensal intestinal flora and considered beneficial for health, as they compete with pathogens for adhesion sites in the intestine and ferment otherwise indigestible compounds. Another important property of these so-called probiotic bacteria...... with bacteria, and the cytokine pattern induced by specific bacteria resembled the pattern induced in MoDC, except for TNF-alpha and IL-6, which were induced in response to different bacteria in blood DC/monocytes and monocyte-derived DC. Autologous NK cells produced IFN-gamma when cultured with blood DC......, monocytes and monocyte-derived DC and IL-12-inducing bacteria, whereas only DC induced IFN-gamma production in allogeneic T cells. In vitro-generated DC is a commonly used model of tissue DC, but they differ in certain aspects from intestinal DC, which are in direct contact with the intestinal microbiota...

  4. Cable Bacteria in Freshwater Sediments

    DEFF Research Database (Denmark)

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus;

    2015-01-01

    In marine sediments cathodic oxygen reduction at the sediment surface can be coupled to anodic sulfide oxidation in deeper anoxic layers through electrical currents mediated by filamentous, multicellular bacteria of the Desulfobulbaceae family, the so-called cable bacteria. Until now, cable...... bacteria have only been reported from marine environments. In this study, we demonstrate that cable bacteria also occur in freshwater sediments. In a first step, homogenized sediment collected from the freshwater stream Giber Å, Denmark, was incubated in the laboratory. After 2 weeks, pH signatures...... marine cable bacteria, with the genus Desulfobulbus as the closest cultured lineage. The results of the present study indicate that electric currents mediated by cable bacteria could be important for the biogeochemistry in many more environments than anticipated thus far and suggest a common evolutionary...

  5. Radiation-resistant asporogenic bacteria

    International Nuclear Information System (INIS)

    This paper reports the biological and ecological examinations on the radiation-resistant asporogenic bacteria (mainly concerning Micrococcus radiodurans). Radiation-resistant asporogenic bacteria were isolated from the irradiated areas of the natural world as well as from the general areas and from the Rn waters in the Misasa hot spring. The acquiring of the tolerance to radiation in bacteria was also examined. In addition, the future problems of microbiological treatment with irradiation were mentioned. (Tsukamoto, Y.)

  6. Bacteriophages of methanotrophic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Tyutikow, F.M. (All-Union Research Inst. for Genetics and Selection of Industrial Microorganisms, Moscow, USSR); Bespalova, I.A.; Rebentish, B.A.; Aleksandrushkina, N.N.; Krivisky, A.S.

    1980-10-01

    Bacteriophages of methanotrophic bacteria have been found in 16 out of 88 studied samples (underground waters, pond water, soil, gas and oil installation waters, fermentor cultural fluids, bacterial paste, and rumen of cattle) taken in different geographic zones of the Soviet Union. Altogether, 23 phage strains were isolated. By fine structure, the phages were divided into two types (with very short or long noncontractile tails); by host range and serological properties, they fell into three types. All phages had guanine- and cytosine-rich double-stranded deoxyribonucleic acid consisting of common nitrogen bases. By all of the above-mentioned properties, all phages within each of the groups were completely identical to one another, but differed from phages of other groups.

  7. Bacteria, phages and septicemia.

    Directory of Open Access Journals (Sweden)

    Ausra Gaidelyte

    Full Text Available The use of phages is an attractive option to battle antibiotic resistant bacteria in certain bacterial infections, but the role of phage ecology in bacterial infections is obscure. Here we surveyed the phage ecology in septicemia, the most severe type of bacterial infection. We observed that the majority of the bacterial isolates from septicemia patients spontaneously secreted phages active against other isolates of the same bacterial strain, but not to the strain causing the disease. Such phages were also detected in the initial blood cultures, indicating that phages are circulating in the blood at the onset of sepsis. The fact that most of the septicemic bacterial isolates carry functional prophages suggests an active role of phages in bacterial infections. Apparently, prophages present in sepsis-causing bacterial clones play a role in clonal selection during bacterial invasion.

  8. Biomarcadores del estado inflamatorio: nexo de unión con la obesidad y complicaciones asociadas Inflammatory biomarkers: the link between obesity and associated pathologies

    Directory of Open Access Journals (Sweden)

    M.ª A. Zulet

    2007-10-01

    Full Text Available El objetivo de este trabajo ha consistido en realizar una revisión de los biomarcadores que actualmente se proponen como el nexo de unión entre la inflamación, la obesidad y complicaciones asociadas, seleccionando los estudios llevados a cabo y las cuestiones pendientes. Cada vez hay mayor evidencia científica de que la inflamación puede jugar un papel importante en la etiología de diversas enfermedades crónicas de gran relevancia para la salud pública. En los últimos años, distintos estudios han sugerido que la obesidad podría ser un desorden inflamatorio. Asimismo, el estrés oxidativo se ha propuesto como un potencial inductor de la inflamación y de la susceptibilidad a la obesidad y patología asociadas. Entre los biomarcadores relacionados con la obesidad, la resistencia insulínica, las enfermedades cardiovasculares y el síndrome metabólico se encuentran: el factor de necrosis tumoral alfa, interleuquinas 6 y 18, angiotensinógeno, factor de crecimiento TGF-beta, inhibidor de la activación del plasminógeno, leptina, resistina, proteína C reactiva, amiloide A, ácido siálico, marcadores de disfunción endotelial (factor von Willebrand, ICAMs, vCAMs factor 3 del sistema del complemento, haptoglobina, glicoproteína zinc-alfa2, eotaxina, visfatina, apelina, alfa1-antitripsina, vaspina, omentina, proteína transportadora de retinol 4, ceruloplasmina, adiponectina y desnutrina. Algunos de estos biomarcadores son buenos predictores de riesgo cardiovascular (inhibidor de la activación de plasminógeno 1, angiotensinógeno, fibrinógeno, ácido siálico, factor 3 del complemento y proteína C reactiva, adiposidad (leptina, visfatina, resistina, haptoglobina y/o resistencia insulínica (ácido siálico, proteína C reactiva, inhibidor de la activación de plasminógeno 1, factor von Willebrand. Sin embargo, todavía queda por dilucidar el papel de muchos de ellos en la etiología de la obesidad y comorbilidades asociadas en

  9. Swimming bacteria in liquid crystal

    Science.gov (United States)

    Sokolov, Andrey; Zhou, Shuang; Aranson, Igor; Lavrentovich, Oleg

    2014-03-01

    Dynamics of swimming bacteria can be very complex due to the interaction between the bacteria and the fluid, especially when the suspending fluid is non-Newtonian. Placement of swimming bacteria in lyotropic liquid crystal produces a new class of active materials by combining features of two seemingly incompatible constituents: self-propelled live bacteria and ordered liquid crystals. Here we present fundamentally new phenomena caused by the coupling between direction of bacterial swimming, bacteria-triggered flows and director orientations. Locomotion of bacteria may locally reduce the degree of order in liquid crystal or even trigger nematic-isotropic phase transition. Microscopic flows generated by bacterial flagella disturb director orientation. Emerged birefringence patterns allow direct optical observation and quantitative characterization of flagella dynamics. At high concentration of bacteria we observed the emergence of self-organized periodic texture caused by bacteria swimming. Our work sheds new light on self-organization in hybrid bio-mechanical systems and can lead to valuable biomedical applications. Was supported by the US DOE, Office of Basic Energy Sciences, Division of Materials Science and Engineering, under the Contract No. DE AC02-06CH11357.

  10. Inventario de la entomofauna asociada al cultivo de pitahaya amarilla (Selenicereus megalanthus Haw. en Briceño (Boyacá

    Directory of Open Access Journals (Sweden)

    Héctor Iván Patiño-Tiria

    2015-04-01

    Full Text Available Boyacá es uno de los departamentos con mayor producción de pitahaya amarilla en el país. Los estudios realizados sobre este cultivo son muy pocos, y el conocimiento de la entomofauna asociada a él es un punto de partida para realizar nuevas investigaciones que permitan identificar la entomofauna asociada a este cultivo en el municipio de Briceño (Boyacá. El desarrollo de esta investigación se llevó a cabo en plantaciones de pitahaya en tres fincas del municipio de Briceño (Boyacá. Se realizaron muestreos empleando métodos activos, como captura manual directa, uso de red y aspirador entomológico, y métodos pasivos, como trampas con atrayentes y trampas  de caída. Los insectos colectados se sometieron a cámara letal y luego se montaron en alfileres para su posterior identificación con ayuda del estereoscopio y claves taxonómicas. En las tres fincas se identificaron un total de 9 órdenes y 58 familias, y los órdenes Hymenóptera y Díptera se reportaron con la mayor cantidad de individuos benéficos. En la finca San Pablo se observó la mayor cantidad de insectos; también fue la única en donde se evidenció la presencia de la plaga más limitante para este cultivo, que es Dasiops saltans (mosca del botón floral. La cantidad de familias presentes en los muestreos se ve influenciada más por el manejo agronómico implementado en cada finca que por las variables climatológicas, como temperatura, humedad relativa y precipitación.

  11. Neumonía intersticial linfoidea asociada a inmunodeficiencia común variable Interstitial lymphoid pneumonia associated with common variable immunodeficiency

    Directory of Open Access Journals (Sweden)

    Gonzalo Peralta

    2011-10-01

    Full Text Available La neumonía intersticial linfoidea (NIL es una rara entidad, descripta como hiperplasia no neoplásica del tejido linfoide pulmonar y clasificada dentro de las enfermedades intersticiales idiopáticas. Se la ha descripto asociada a infección por HIV, fenómenos autoinmunes, hipergamaglobulinemia policlonal o menos frecuentemente a hipogammaglobulinemia. Presentamos una paciente de 66 años de edad con diabetes mellitus, síndrome de Sjögren e hipertensión arterial, derivada a nuestro centro por tos seca y disnea clase funcional II-III. En el examen físico presentaba rales tipo “velcro” bibasales y esplenomegalia. Los estudios de laboratorio evidenciaron plaquetopenia (50 000/mm³ e hipogammaglobulinemia; la tomografía axial computarizada (TAC de tórax mostró compromiso intersticial bibasal, con nódulos peribroncovasculares menores a un centímetro. Se realizó una videotoracoscopia con biopsia pulmonar, la anatomía patológica mostró hallazgos compatibles con neumonía intersticial linfoidea. Se inició tratamiento con metilprednisona 40 mg/día vía oral e infusión endovenosa de gammaglobulina 500 mg/kg, mensual, evolucionando con mejoría clínico-radiológica. Por persistencia de plaquetopenia, asociada a hiperesplenismo, se realizó esplenectomía con buena respuesta. En la anatomía patológica no se observo clonalidad linfoide.The interstitial lymphoid pneumonia (LIP is an uncommon disorder, described as non-neoplastic lung lymphoid tissue hyperplasia and classified as an interstitial lung disease. It has been described in association with HIV infection, autoimmune disorders, policlonal hypergammaglobulinemia and less frequently, with hypogammaglobulinemia. We report the case of a 66 year old female patient with a history of diabetes, Sjögren syndrome and hypertension. She was referred to our hospital due to a dry cough and dyspnea (FC II-III. The physical examination showed bilateral dry crackles and splenomegaly

  12. Estudio de las torres de refrigeración asociadas a brotes comunitarios de legionelosis Study of refrigeration towers associated with community outbreaks of legionellosis

    Directory of Open Access Journals (Sweden)

    Albert Pérez Lleonart

    2007-08-01

    Full Text Available Objetivo: Evaluar los factores de riesgo de las torres de refrigeración asociadas a un brote comunitario de legionelosis según sus características de mantenimiento y la calidad del agua. Método: Comparar los datos recogidos entre los 4 tipos de torres de refrigeración: control 1, control 2, probable y confirmada. Se han estudiado un total de 184 torres de refrigeración asociadas a 17 brotes comunitarios de legionelosis de la provincia de Barcelona durante el año 2004, de las cuales 112 son control 1, 54 control 2, 8 probables y 10 confirmadas. Resultados: Las torres confirmadas se caracterizan por: niveles elevados de conductividad, aerobios totales, dureza cálcica, sólidos totales en disolución, temperatura y turbidez; concentraciones de cloro deficientes (Objetive: To evaluate the factors of risk of the risk cooling towers associated to a community outbreak of legionellosis according to its characteristics of maintenance and the quality of the water with the purpose of improving the systems of prevention of this one disease. Method: To compare the piece of information gathered between the 4 types of cooling towers: control 1, control 2, probable and confirmed. A total of 184 cooling towers have been studied associated to 17 community outbreak of legionellosis of the province of Barcelona (Spain during the year 2004, of which 112 are control 1, 54 control 2, 8 probable and 10 confirmed. Results: The confirmed towers are characterized by: high levels of conductivity, total aerobes, calcic hardness, total solids in dissolution, temperature and turbidity; low levels of chlorine (< 2 ppm; of use hypochlorite as disinfectant in a 10%; greater degree of breach of the revision program and cleaning of the internal elements of the tower (tray, stuffed and separating of drops; degree of performance of the periodic disinfections and the cleaning of deposits of the 100%. A 47% of the investigated towers do not use the previous treatments of the

  13. Desequilibrios metabólicos con especial referencia a las carenciales de minerales asociadas a problemas reproductivos en vacas lecheras de Cuba (Metabolic imbalances and minerals deficiencies associated with reproductive disorders in dairy cattle in Cuba)

    OpenAIRE

    García Díaz, Juan R; Silveira Prado, Enrique A; Cuesta Mazorra, Mario; Quiñones Ramos, Reinaldo; Hernández Barreto, Miguel A.; Mollineda Trujillo, Ángel

    2011-01-01

    ResumenEl objetivo de este estudio fue diagnosticar los principales desequilibrios metabólicos con especial referencia a las carenciales de minerales asociadas a los problemas reproductivos en vacas lecheras mestizas Holstein x Cebú en un sistema de producción con amamantamiento restringido en la región central de Cuba.SummaryThe objective of this study was to diagnose the principal metabolic imbalances and deficiencies associated with reproductive disorders especially due to mineral deficien...

  14. Análisis morfológico de escarpas asociadas a una falla de intraplaca con actividad cuaternaria: falla Las lagunas, Córdoba

    Directory of Open Access Journals (Sweden)

    Diego Villalba

    2014-03-01

    Full Text Available El objetivo de la presente contribución es, mediante el análisis cuantitativo de la morfología de escarpas de falla desarrolladas sobre sedimentos cuaternarios, estimar las edades de las reactivaciones prehistóricas e históricas de la falla Las Lagunas. El área de estudio se ubica al SO del departamento Río Cuarto, en el sector pedemontano de la sierra de Comechingones entre las localidades de Achiras y Sampacho, a 33° 18' S y 64° 49´ O, región central de Argentina. El análisis morfológico cuantitativo se realizó mediante la obtención de perfiles topográficos de detalle transversales a la traza de la estructura y la aplicación de curvas de regresión para determinar sus edades. Esto permitió interpretar que las evidencias de deformación mecánica, ruptura en superficie, corresponden a, al menos, cuatro fuertes terremotos asociados a esta falla con ocurrencia en los últimos 10 ka. Con esta información se elaboró una curva de aproximación característica para rupturas en superficie, asociadas a esta falla, de edades menores o iguales a 100 años.

  15. Edad y caracterización de una mica de litio asociada a un sistema de greisen en Mina la Rosario, Sierra de Fiambalá, Catamarca

    Directory of Open Access Journals (Sweden)

    Julio C. Avila

    2008-03-01

    Full Text Available En el presente trabajo se realiza el estudio mineralógico y se define la edad de una mica de litio obtenida en las salbandas de las vetas cuarzo portadoras de wolframita de mina La Rosario, ubicada en las proximidades del granito Ayacucho, Sierra de Fiambalá, Sierras Pampeanas Occidentales de la provincia de Catamarca. Esta especie mineral fue identificada a través de diferentes técnicas analíticas que incluyen determinaciones por difracción de rayos X, análisis químicos y por espectrometría infrarroja. Los resultados de los estudios indican que su estructura corresponde a una zinnwaldita y su composición química permite ubicarla dentro de la serie biotita-siderofilita-zinnwaldita-lepidolita. Las edades isotópicas obtenidas para el Granito Ayacucho (340 ± 8 Ma y esta mica hidrotermal (339 ± 8 Ma confirman una edad carbonífera para este intrusivo y la estrecha relación temporal con la mineralización hidrotermal asociada.

  16. Construcción del cuestionario de “Concepciones sobre inclusión educativa de alumnos con necesidades educativas especiales asociadas a discapacidad intelectual” (CIEDI

    Directory of Open Access Journals (Sweden)

    Constanza San Martín Ulloa

    2010-01-01

    Full Text Available Las concepciones del profesorado, entendidas como teorías implícitas, constituyen elementos que pueden favorecer u obstaculizar los procesos de inclusión educativa. Con el propósito de explorar y describir las concepciones que docentes y estudiantes chilenos de pedagogía mantienen sobre la inclusión de alumnos que presentan discapacidad intelectual, y debido a la carencia de instrumentos acordes con este objetivo, se construyó un cuestionario de 25 dilemas, organizados en tres dimensiones de análisis. En este artículo, se describen las fases del proceso de elaboración del cuestionario de “Concepciones sobre inclusión educativa de alumnos con necesidades educativas especiales asociadas a discapacidad intelectual” (CIEDI. Los resultados indicaron que es posible identificar dos perspectivas extremas en las concepciones del profesorado, unas cercanas a planteamientos segregadores y otras más acordes con el paradigma inclusivo. Se advierte una menor consistencia de la teoría interpretativa, lo que podría confirmar su carácter transitorio y evolutivo.

  17. Alteraciones morfológicas de las vellosidades placentarias asociadas a malformaciones fetales múltiples del sistema esquelético

    Directory of Open Access Journals (Sweden)

    Ángela López

    2013-09-01

    Full Text Available OBJETIVOS: describir y cuantificar alteraciones morfológicas en vellosidades placentarias de embarazadas cuyo feto desarrolló malformaciones esqueléticas múltiples. MÉTODOS: se analizaron cuatro placentas de abortos terapéuticos a las 13, 16, 20 y 38 semanas de gestación. Estas se compararon con placentas normales a la misma edad de gestación de abortos electivos por indicación médico legal. Tinción de hematoxilinaeosina se aplicó a 10 láminas de 5 regiones de cada placenta utilizando un protocolo con 4 variables cuantitativas: madurez, cambios fibrinoides, edema y fibrosis estromal y una variable cualitativa: trombosis. Los resultados cuantitativos se analizaron utilizando el análisis de varianza (ANAVAR según arreglo completamente aleatorizado y el test de Tukey. Para la variable cualitativa se aplicó la prueba de tendencia para datos correlacionados. Se empleó el software statistix 8.0 y SAS 9.0 para Windows. RESULTADOS: existen diferencias significativas (p0,05 en relación a la variable cualitativa. CONCLUSIONES: la población de vellosidades placentarias asociadas a malformaciones múltiples del sistema esquelético presentó un alto porcentaje de alteraciones indicando que la barrera placentaria está dañada afectando el intercambio de gases, nutrientes y metabolitos durante el desarrollo del feto.

  18. Paquimeningitis hipertrófica, glomerulonefritis y vasculitis de pequeños vasos asociada a ANCA Hypertrophic pachymeningitis, glomerulonephritis and P-ANCA associated small vessel vasculitis

    Directory of Open Access Journals (Sweden)

    Octavio Mazzocchi

    2007-04-01

    Full Text Available La paquimeningitis hipertrófica es una enfermedad poco frecuente caracterizada por engrosamiento de la duramadre. Presentamos una paciente con esta enfermedad que se manifestó con cefalea crónica y en la que concomitantemente se evidenció una glomerulonefritis necrotizante extracapilar pauciinmune asociada a anticuerpos anticitoplasma de neutrófilos de patrón perinuclear (ANCA-P. El diagnóstico se estableció por resonancia nuclear magnética. Recibió tratamiento inmunosupresor con prednisona y ciclofosfamida con evolución favorable.Hypertrophic pachymeningitis is a very unusual disease, the main characteristic of which is thickening of the dura mater. We describe a patient who started this illness showing chronic headache and pauci-immune necrotizing extracapillary perinuclear antineutrophil cytoplasmic antibody (P-ANCA associated glomerulonephritis. The diagnosis was made by brain magnetic resonance image. She received immunosuppressant therapy with prednisonel and cyclophosphamide with clinical improvement.

  19. Concepciones teóricas de Neuman asociadas con la prevención de las úlceras por presión: un estudio de caso

    Directory of Open Access Journals (Sweden)

    Jairo Edielson Rodrigues Barbosa de Sousa

    2015-12-01

    Full Text Available Relato de caso que tiene como objetivo mostrar cómo el uso de la Teoría de Neuman asociada con la prevención de las úlceras por presión (UPP utilizando la Escala de Braden como estándar clínico, es eficaz para reducir la incidencia de UPP en la unidad de cuidados intensivos. Se presenta el caso de una anciana de 94 años, ingresada por insuficiencia respiratoria aguda, con diagnósticos asociados de neumonía y diabetes descompensada en la Unidad de Cuidados Intensivos (UCI de un hospital en Teresina, Piauí, Brasil. Durante los 64 días en que estuvo en la UCI, aunque que tuviera muchos factores de riesgo, no ha presentado ninguna UPP, mostrando cómo las medidas preventivas que fueron llevadas a cabo han sido eficaces para la prevención.

  20. Environmental management project of the Patache power plant project and associated transmission line; Gestion ambiental proyecto central termoelectrica Patache y linea de transmision asociada

    Energy Technology Data Exchange (ETDEWEB)

    Carreno Paredes, Cristian [Compania Electrica Tapaca (CELTA, S. A.), (Chile)

    1996-12-31

    This report makes a brief description of the services developed by INGENDESA of the projects executed in the area of engineering as well as in the area of environmental matters. In a second instance a relatively detailed presentation is made of the most important background of the Chilean project: {sup E}nvironmental Management of the Patache Power Plant and the Associated Transmission Line-Compania Electrica Tarapaca (CELTA, S.A.) Region I{sup .} The justification for the construction of the power plant and the environmental problems associated with the same are described [Espanol] En el presente informe se hace una breve presentacion de los servicios desarrollados por INGENDESA, de los proyectos elaborados tanto en el area de la ingenieria como en la tematica ambiental. En segunda instancia, se hace una presentacion relativamente detallada de los antecedentes mas importantes del proyecto chileno {sup G}estion Ambiental Central Patache y Linea de Transmision Asociada - Compania Electrica Tarapaca (CELTA, S.A.) I Region{sup .} Se describe la justificacion de la construccion de esta central termoelectrica y los problemas ambientales asociados a la misma

  1. Sampling bacteria with a laser

    Science.gov (United States)

    Schwarzwälder, Kordula; Rutschmann, Peter

    2014-05-01

    Water quality is a topic of high interest and it's getting more and more important due to climate change and the implementation of European Water Framework Directive (WFD). One point of interest here is the inflow of bacteria into a river caused by combined sewer overflows which lead untreated wastewater including bacteria directly into a river. These bacteria remain in the river for a certain time, they settle down and can be remobilised again. In our study we want to investigate these processes of sedimentation and resuspension and use the results for the development of a software module coupled with the software Flow3D. Thereby we should be able to simulate and therefore predict the water quality influenced by combined sewer overflows. Hence we need to get information about the bacteria transport and fate. We need to know about the size of the bacteria or of the bacteria clumps and the size of the particles the bacteria are attached to. The agglomerates lead to different characteristics and velocities of settlement. The timespan during this bacteria can be detected in the bulk phase depends on many factors like the intensity of UV light, turbidity of the water, the temperature of the water, if there are grazers and a lot more. The size, density and composition of the agglomerates is just a part of all these influencing factors, but it is extremely difficult to differ between the other effects if we have no information about the simple sedimentation in default of these basic information. However we have a big problem getting the data. The chaining between bacteria or bacteria and particles is not too strong, so filtering the water to get a sieving curve may destroy these connections. We did some experiments similar to PIV (particle image velocimetry) measurements and evaluated the pictures with a macro written for the software ImageJ. Doing so we were able to get the concentration of bacteria in the water and collect information about the size of the bacteria. We

  2. Beer spoilage bacteria and hop resistance

    NARCIS (Netherlands)

    Sakamoto, K; Konings, WN

    2003-01-01

    For brewing industry, beer spoilage bacteria have been problematic for centuries. They include some lactic acid bacteria such as Lactobacillus brevis, Lactobacillus lindneri and Pediococcus damnosus, and some Gram-negative bacteria such as Pectinatus cerevisiiphilus, Pectinatus frisingensis and Mega

  3. Antimicrobial Effect of Lactic Acid Bacteria against Common Pathogenic Bacteria

    Directory of Open Access Journals (Sweden)

    Mohammad Mohammaddoost Chakoosari ( Msc

    2016-01-01

    Full Text Available Background and Objective: Probiotics are living microorganisms that have beneficial effects on the health of digestive system. The aim of this study was to evaluate the antimicrobial ability of acidic and neutral supernatants (culture supernatant of lactic acid bacteria against common bacterial pathogens. Methods: Four species of lactic acid bacteria (Lactobacillus plantarum PTCC1745, Lactobacillus PTCC1608, Lactobacillus Saki PTCC1712 and Lactobacillus Lactis PTCC1336 were obtained from the microbial collection of Iranian Research Organization for Science and Technology in Lyophilized form. The antimicrobial activity of neutral and acidic supernatants against bacterial pathogens was investigated using the Disk and Well Diffusion Agar methods. Results: Lactic acid bacteria showed good antimicrobial ability against six pathogenic bacteria with the highest inhibitory effect observed in Lactococcus lactis against E. coli PTCC1399 through well method with an average diameter of 14 mm inhibition zone. In this study, the well diffusion method was far more sensitive compared to the disk method and acidic supernatants showed higher antimicrobial efficiency compared to neutral types. Conclusion: the Metabolites produced by lactic acid bacteria are able to inhibit the growth of pathogenic bacteria that can be an important and practical solution for the prevention and treatment of infections and ultimately improve human health. Keywords: Lactobacillus; Lactococcus; Probiotic; Antibacterial

  4. Screening of aspartate dehydrogenase of bacteria

    OpenAIRE

    Fukuda, Shoko; Okamura, Tokumitsu; Yasumasa, Izumi; Takeno, Tomomi; Ohsugi, Masahiro

    2001-01-01

    Fifty-two strains of bacteria cultured under aerobic conditions and 12 strains of bacteria cultured under anaerobic conditions demonstrated high activity staining of aspartate dehydrogenase with NAD^+. Four strains of bacteria cultured under aerobic conditions and 7 strains of bacteria cultured under anaerobic conditions demonstrated high activity staining of aspartate dehydrogenase with NADP^+. Seven strains of bacteria cultured under aerobic conditions and 4 strains of bacteria cultured und...

  5. Bacteria, fungi and protozoa paper

    Data.gov (United States)

    U.S. Environmental Protection Agency — Bacteria and fungi in source and treated drinking water This dataset is associated with the following publication: King , D., S. Pfaller , M. Donohue , S. Vesper ,...

  6. Adherention ability of intestinal bacteria

    OpenAIRE

    Morgensternová, Tereza

    2014-01-01

    Probiotics are live microorganisms that provide positive health benefits. Bacteria of the genus Bifidobacterium belong to this group. These bacteria have to meet a number of criteria so that they could be considered for probiotic. These include the ability to survive, grow, and be metabolically active in the gastrointestinal tract of the recipient. Probiotics protect the intestinal mucus from the adhesion of pathogenic organisms. The aim of this thesis was to test the ability of different ...

  7. Thymidine kinase diversity in bacteria

    DEFF Research Database (Denmark)

    Sandrini, Michael; Clausen, A.R.; Munch-Petersen, B.;

    2006-01-01

    Thymidine kinases (TKs) appear to be almost ubiquitous and are found in nearly all prokaryotes, eukaryotes, and several viruses. They are the key enzymes in thymidine salvage and activation of several anti-cancer and antiviral drugs. We show that bacterial TKs can be subdivided into 2 groups. The....... The TKs from Gram-positive bacteria are more closely related to the eukaryotic TK1 enzymes than are TKs from Gram-negative bacteria....

  8. A comparative effect of 3 disinfectants on heterotrophic bacteria, iron bacteria and sulfate-reducing bacteria

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The disinfection effect of chlorine dioxide, chlorine and their mixture on heterotrophic bacteria, iron bacteria and sulfate-reducing bacteria in circulating cooling water was studied. The results of the test indicated that high purity chlorine dioxide was the most effective biocide in the 3 disinfectants, and with a dosage of 0.5mg/L, chlorine dioxide could obtain perfect effect. High purity chloride dioxide could have the excellent effect with the pH value of 6 to 10, and could keep it within 72 h. Chlorine and their mixture couldn't reach the effect of chlorine dioxide.

  9. Bioreporter bacteria for landmine detection

    Energy Technology Data Exchange (ETDEWEB)

    Burlage, R.S. [Oak Ridge National Lab., TN (United States); Youngblood, T. [Frisby Technologies, Aiken, SC (United States); Lamothe, D. [American Technologies, Inc., Huntsville, AL (United States). Ordnance/Explosives Environmental Services Div.

    1998-04-01

    Landmines (and other UXO) gradually leak explosive chemicals into the soil at significant concentrations. Bacteria, which have adapted to scavenge low concentrations of nutrients, can detect these explosive chemicals. Uptake of these chemicals results in the triggering of specific bacterial genes. The authors have created genetically recombinant bioreporter bacteria that detect small concentrations of energetic chemicals. These bacteria are genetically engineered to produce a bioluminescent signal when they contact specific explosives. A gene for a brightly fluorescent compound can be substituted for increased sensitivity. By finding the fluorescent bacteria, you find the landmine. Detection might be accomplished using stand-off illumination of the minefield and GPS technology, which would result in greatly reduced risk to the deminers. Bioreporter technology has been proven at the laboratory scale, and will be tested under field conditions in the near future. They have created a bacterial strain that detects sub-micromolar concentrations of o- and p-nitrotoluene. Related bacterial strains were produced using standard laboratory protocols, and bioreporters of dinitrotoluene and trinitrotoluene were produced, screening for activity with the explosive compounds. Response time is dependent on the growth rate of the bacteria. Although frill signal production may require several hours, the bacteria can be applied over vast areas and scanned quickly, producing an equivalent detection speed that is very fast. This technology may be applicable to other needs, such as locating buried explosives at military and ordnance/explosive manufacturing facilities.

  10. Isolation and Identification of Concrete Environment Bacteria

    Science.gov (United States)

    Irwan, J. M.; Anneza, L. H.; Othman, N.; Husnul, T.; Alshalif, A. F.

    2016-07-01

    This paper presents the isolation and molecular method for bacteria identification through PCR and DNA sequencing. Identification of the bacteria species is required in order to fully utilize the bacterium capability for precipitation of calcium carbonate in concrete. This process is to enable the addition of suitable catalyst according to the bacterium enzymatic pathway that is known through the bacteria species used. The objective of this study is to isolate, enriched and identify the bacteria species. The bacteria in this study was isolated from fresh urine and acid mine drainage water, Kota Tinggi, Johor. Enrichment of the isolated bacteria was conducted to ensure the bacteria survivability in concrete. The identification of bacteria species was done through polymerase chain reaction (PCR) and rRDNA sequencing. The isolation and enrichment of the bacteria was done successfully. Whereas, the results for bacteria identification showed that the isolated bacteria strains are Bacillus sp and Enterococus faecalis.

  11. Regional differences in astrocyte activation in HIV-associated dementia Diferencias regionales en la activación astrocitaria en demencia asociada a HIV

    Directory of Open Access Journals (Sweden)

    María C. Vanzani

    2006-04-01

    Full Text Available Since astrogliosis is a histological marker usually observed in HIV-associated dementia (HIV-D, we decided to investigate the potential relationship between the expression of glial fibrillary acidic protein (GFAP and the regional distribution of cells positive (+ for this specific marker of astrocyte activation. Histological sections of brain tissues obtained at necropsy from 5 HIV-D patients and 5 age-matched controls without history of neuropsychiatric illness were immunostained with peroxidase. Mean numbers of GFAP(+ astrocytes were significantly increased in entorhinal cortex, hippocampus and subcortical white matter of patients, but values in frontal cortex and basal ganglia were similar to those of controls. In contrast, surface density of immunoreactive GFAP was significantly increased in all tested brain areas from all patients, including unusually affected regions such as entorhinal cortex and hippocampus. Therefore, such consistent finding of hypertrophic astrocytes, ranging from highest cell percentajes in subcortical white matter to lowest in basal ganglia indicates that quantification of surface density in GFAP (+ cells appears to be a more reliable approach to score gliosis than the counting of their cell nuclei. Because astrocyte activation involves both protective and detrimental effects on adjacent neuronal subsets, the evidence of regional differences in this reactive potential highlights the importance of accurately defining their contribution to the neuropathogenesis not only of HIV-D, but of a wide range of neurodegenerative disorders.Siendo la astrogliosis un signo histológico habitualmente presente en demencia asociada a HIV, se investigó la eventual relación entre expresión de proteína gliofibrilar ácida (GFAP y localización regional de células positivas para ese marcador específico de la activación astrocitaria. Por inmunoperoxidasa, se procesaron cortes histológicos de tejidos cerebrales obtenidos por

  12. Prevalencia de la sintomatología del Síndrome de Asperger y variables asociadas en preescolares españoles

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    Eva A. Araújo Jiménez

    2012-01-01

    Full Text Available El Síndrome de Asperger (AS forma parte del espectro de trastornos autistas, su estudio es reciente para el caso de edades tempranas. El objetivo de esta investigación es determinar la prevalencia de los síntomas del AS en población preescolar general, rural y urbana en preescolares de España. Además, analizamos las áreas de desarrollo y síntomas de ansiedad asociados a la presencia de sintomatología del AS. La muestra de este estudio se conforma de 1104 preescolares de 3 a 6 años de edad. La presencia de síntomas del AS se evaluó con base en el reporte de padres y maestros, mediante un instrumento de detección de desórdenes psiquiátricos. La prevalencia informada por padres fue de 11,7%, mientras que para los maestros fue de 8,1%. La presencia de sintomatología del AS se asoció a retrasos en el desarrollo de la comprensión del lenguaje, la coordinación motora, las habilidades de autoayuda y la práctica de juegos. Además, nuestros resultados indican que el AS tiene una fuerte relación con síntomas de fobia específica y tics. Concluimos que es posible hacer una detección temprana de la sintomatología del AS, ya que encontramos prevalencias similares a otras descritas en investigaciones recientes. Dada la afectación asociada al AS, su detección es altamente recomendable.

  13. Las bioconstrucciones de corales y sus facies asociadas durante el Malm en la Cordillera Ibérica Central (provincia de Zaragoza

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    Meléndez, A.

    1987-08-01

    Full Text Available The differents types of bioconstructions and associated facies in the Central Iberian Chain (Higueruelas Formation, Upper Kimmeridgian have been studied. Biohermes of different thickness (decimetric to metric and less lateral continuity are developped, highly colonized by corals, that are associated to oncolitic, bioclastic and oolitic of high energy facies, in marginal areas, near the litoral developpment. At the same time takes place an important set up of mud mounds, with a small coral colonisation, in protected arcas in a inner shelf, or in outer areas, where the action of the waves is not so effective. The environment protection is been generated in some places due to the appearance of oolitic barrier islands.Se estudian los diferentes tipos de bioconstrucciones de corales, y sus facies asociadas, presentes en el sector central de la rama aragonesa de la Cordillera Ibérica, en la Formación Higueruelas (Kimmeridgiense superior. Se desarrollan biohermos de potencias métricas a decimétricas y escasa continuidad lateral, intensamente colonizados por corales coloniales, que se encuentran asociados a facies oncolíticas, bioclásticas y oolíticas de alta energía en zonas marginales, próximas al desarrollo litoral. Al mismo tiempo tiene lugar una importante instalación de mud mounds, con escasa colonización de corales, en zonas protegidas dentro de la plataforma interna o en zonas más externas, donde la acción del oleaje no es efectiva. La protección del medio viene condicionada en algunos puntos por la aparición de islas barrera oolíticas.

  14. ESTRATEGIAS DE GESTIÓN DE LA INFORMACIÓN ASOCIADAS A LA INTELIGENCIA COMPETITIVA: APROPIACIÓN PRÁCTICA EN ORGANIZACIONES DE APOYO A EMPRESAS EXPORTADORAS

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    Guarrochena de Arjol, Marina

    2013-01-01

    Full Text Available Se propone un diseño de estrategias orientadas a facilitar la gestión de la información, asociadas a la apropiación de la Inteligencia Competitiva, como proceso anticipatorio del uso de los recursos de gestión comercial, mercado y desarrollo de capacidades y ventajas competitivas; como práctica en organizaciones público-privadas de apoyo a pequeñas y medianas empresas exportadoras de madera de Misiones.La amplitud y diversidad de información para la toma de decisiones organizacionales es compleja para alcanzar a percibir las señales indicadoras de cambios significativos en el entorno externo, como ventajas diferenciales para la acción y sustentabilidad de la organización.El antecedente de una investigación de mercados de la madera proporcionó resultados relevantes de cambios que se producen en su ambiente externo y dentro de la empresa, para direccionar las actividades de seguimiento. Esto permite identificar los aspectos críticos en la gestión empresarial frente a la dinámica del mercado, y diseñar las alternativas estratégicas de información para el desarrollo exportador, en el sostenimiento de relaciones entre las empresas y la institucionalidad de apoyo.Los ejes estratégicos guían hacia la generación de sistemas de información de mercados, mejoras de acceso a los mercados, desarrollo de capacidades, sustentabilidad en la gestión y difusión del conocimiento.

  15. Contenido de N, P, K y rendimiento de frambuesa roja (Rubus idaeus L. ‘Autumn bliss’ orgánico asociada con lupino (Lupinus mutabilis Sweet.

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    Enoc Jara-Peña

    2013-06-01

    Full Text Available Este trabajo se realizó con el objetivo de determinar la respuesta de la frambuesa ‘Autumn Bliss’ productora de otoño a la aplicación de un biofertilizante (vermicomposta asociada con lupino, en condiciones de invernadero en Montecillo, México. En el ensayo se estudiaron 5 niveles de vermicomposta (0, 30, 60, 90 y 120 g maceta–1 y 2 niveles de asociación (con o sin lupino totalizando 10 tratamientos y un tratamiento adicional que consistió de fertilización química (N100 P80 K80 . Como material vegetal se utilizaron brotes adventicios de frambuesa tratadas con frío durante 60 días a 5 °C. Se encontraron diferencias estadísticamente significativas a los niveles de vermicomposta incorporada al sustrato, y niveles de 60 hasta 90 g maceta–1 favorecieron las mayores concentraciones de N y K en frambuesa. Cuando la frambuesa se asoció con lupino, permitió una mayor acumulación de P, lo que indica una interacción positiva entre estos elementos. El mayor rendimiento en peso y en número de frutos se obtuvo con la aplicación de 90 g maceta–1 de vermicomposta. Sin embargo, cuando la frambuesa se asoció con lupino el mayor rendimiento en peso y en número de frutos se obtuvo con aplicación de 120 g maceta–1 de vermicomposta.

  16. Condiciones locales de vulnerabilidad asociadas con dengue en dos comunidades de Morelos Local conditions of vulnerability associated with dengue in two communities of Morelos

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    Silvia Chuc

    2013-04-01

    Full Text Available OBJETIVO: Evaluar las condiciones de vulnerabilidad asociadas con la ocurrencia de dengue en dos localidades de Morelos en los años 2006 a 2009. MATERIAL Y MÉTODOS: se aplicó una encuesta sobre conocimientos, percepción de riesgo, prácticas de prevención y uso del agua en dos localidades de Morelos. Mediante un análisis de componentes principales, se construyó un índice de vulnerabilidad local al dengue (IVL. La asociación del IVL con la enfermedad en la vivienda se evaluó mediante una prueba de ji cuadrada. RESULTADOS: El IVL incluyó cinco componentes explicando el 63% de la varianza y fue clasificado en tres categorías: baja, media y alta. Se observó una asociación significativa entre el aumento de la vulnerabilidad y la prevalencia del reporte de casos de dengue en las localidades. CONCLUSIÓN: El estudio de la vulnerabilidad al dengue permite identificar necesidades locales específicas en materia de promoción de la salud.OBJECTIVE: To evaluate the vulnerability associated with the occurrence of dengue in two villages of Morelos, Mexico from 2006 to 2009. MATERIALS AND METHODS. A survey on knowledge, risk perception, prevention practices and water use was applied in two villages of Morelos. Using a principal component analysis, an index of local vulnerability to dengue (IVL was constructed. The association of IVL with the disease at home was assessed using a Chi-square test. RESULTS: The IVL included five components explaining 63% of the variance and was classified in three categories: low, medium and high. There was a significant association between increased vulnerability and prevalence of reported cases of dengue in Temixco and Tlaquiltenango. CONCLUSION: The study of vulnerability to dengue allows us to identify local needs in the field of health promotion.

  17. Caracterización de las mutaciones en el gen rpoβ asociadas a la rifampicina en pacientes con tuberculosis pulmonar

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    Juan Agapito

    2002-07-01

    Full Text Available Antecedentes: La resistencia a rifampicina en M. tuberculosis involucra mutaciones en el gen rpoβ que codifica a la subunidad β de la ARN polimerasa. Objetivo: Identificar las mutaciones del gen rpoβ , en cepas de M. tuberculosis asociadas con resistencia a rifampicina aisladas de la Subregiσn de Salud Lima Norte, Perϊ. Materiales y métodos: Se cultivó en Lowestein - Jenseen 73 muestras de esputo de pacientes con tuberculosis pulmonar. A 62, con más de 10 colonias por tubo, se les comprobó susceptibilidad a isoniazida, rifampicina, estreptomicina y etambutol. Se realizó la extracción de ADN por PCR, clonación en el vector pGEM-T, transformación, selección de clonas recombinantes y secuenciamiento del ADN plasmídico para la determinación de los polimorfismos del gen rpoβ. Resultados: 52 (83,9% cepas fueron resistentes a rifampicina (Rif r y 10 (16,1% susceptibles (Rif s . Se encontró alteraciones en el gen rpoβ en 51 de 52 cepas Rif r Se identificaron 20 mutaciones. Las mutaciones mαs frecuentes fueron encontradas en los codones Ser-531 (62,7%, His-526 (15,7%, Asp-516 (11,8% y Gln-513 (5,9%. No se observσ mutaciσn alguna en las 10 cepas Rif s. 94,2% de nuestras cepas Rif r fueron también resistentes a isoniazida. Conclusiones: Se encontraron mutaciones en el gen rpoB de casi todas las cepas Rif r ; asimismo, casi todas las cepas Rif r fueron también resistentes a isoniazida.

  18. FUENTES DE FOSFATO ASOCIADAS A LA CACHAZA Y EL BIOFERTILIZANTE SOBRE LOS MICROORGANISMOS SOLUBILIZADORES DE FÓSFORO Y SU CONTENIDO EN EL SUELO

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    Cid N. Silva Campos

    2016-01-01

    Full Text Available Los suelos de regiones tropicales presentan una elevada adsorción del fósforo, el cual se encuentra poco disponible para las plantas y limita la producción de los cultivos. Este estudio tuvo como objetivo evaluar el efecto de las fuentes de fosfato acidulado y fosfato natural asociadas a la cachaza, no enriquecida y enriquecida con biofertilizante, sobre la población de microorganismos solubilizadores de fosfatos y los tenores de P en el suelo. El experimento se realizó en condiciones controladas a nivel de laboratorio en la Universidad “Carlos Rafael Rodríguez” de Cienfuegos, Cuba. Las unidades experimentales fueron macetas de 0,5 dm3 conteniendo suelo Ferralítico Calcítico. El diseño experimental utilizado fue completamente aleatorizado con arreglo factorial 3x2+1 y tres repeticiones; tres fuentes de fósforo: superfosfato triple, fosfato monoamónico y fosfato natural de Cuba; cachaza no enriquecida y enriquecida con el biofertilizante Azotofos y un tratamiento control (solo suelo. A los 30 y 60 días después de la aplicación de los tratamientos, se evaluaron la cantidad de microorganismos solubilizadores de P, los niveles de P, la materia orgánica y el pH del suelo. La adición de biofertilizante a la cachaza no tuvo ningún efecto en los niveles de P y la materia orgánica del suelo. La aplicación de fósforo en forma de fosfato natural en presencia de cachaza no enriquecida y enriquecida con biofertilizante proporcionó una mayor población de microorganismos e incrementó el nivel de P en el suelo, en relación con las fuentes de fosfato acidulado.

  19. Relaciones sexuales en adolescentes colombianos y las implicaciones para la salud pública: una revisión de la prevalencia y algunas variables asociadas

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    Adalberto Campo-Arias

    2009-08-01

    Full Text Available ResumenEl deseo sexual se incrementa significativamente durante la adolescencia, en consecuencia, un número importante de hombres y mujeres adolescentes inician relaciones sexuales antes de la mayoría de edad. Se realizó una revisión de las publicaciones en Pubmed y Google académico que informaban la prevalencia de relaciones sexuales en adolescentes colombianos durante la década más reciente (1999-2008. Las palabras clave que se usaron fueron adolescentes (adolescents, estudiantes (students, comportamiento sexual (sexual behavior y Colombia. La prevalencia de relaciones sexuales estuvo entre 7.7% y 58%, media de 27.2%. Más años de edad, sexo masculino, mayor escolaridad y consumo de sustancias legales o ilegales se relacionaron con historia de relaciones sexuales. Los adolescentes informaron conductas sexuales de riesgo, con diferencias por género, como el uso inconsistente de condón, relaciones sexuales bajo el efecto de sustancias y relaciones sexuales con personas poco conocidas. Estos hallazgos tienen relevancia para salud pública sexual y reproductiva. Se deben diseñar programas integrales de intervención para promover un desarrollo sexual armónico y saludable en adolescentes colombianos. [Campo-Arias A. Relaciones sexuales en adolescentes colombianos y las implicaciones para la salud pública: una revisión de la prevalencia y algunas variables asociadas. MedUNAB 2009; 12:86-90].

  20. Estudio de un brote de bacteremia secundaria asociada con nutrición parenteral en una unidad de recién nacidos de tercer nivel.

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    Jaime A. del Río

    2009-10-01

    Full Text Available Ante la evidencia de un brote de bacteremia secundaria neonatal, en la Unidad de Recién Nacidos, Hospital de Caldas, Manizales, se realizó un estudio de casos y controles 1:4, para determinar la asociación de factores de riesgo importantes para los pediatras como nutrición parenteral, terapia respiratoria, tubo orotraqueal, cámara cefálica, parto vaginal, la aplicación de hemoderivado, remisión de otra unidad, leche materna por sonda, peso y edad. Como definición de caso se adoptó la clínica con por lo menos dos hemocultivos positivos, patógeno de piel hemocultivado y germen aislado en sangre sin foco definido. Los 19 controles se tomaron al azar de los recién nacidos que se encontraban hospitalizados por otras causas diferentes o relacionadas con la patología. Se realizó una regresión logística paso a paso, para determinar los eventos causales. Los gérmenes hemocultivados fueron Escherichia coli, Enterobacter gergoviae, E. aerogenes y E. cloacae. La edad promedio de los casos fue 30.6 semanas, en los controles 36.6 meses (p 0.2 NS. Peso promedio de los casos 1,385 g contra 2,621 g en los controles. Se encontró asociada la nutrición parenteral con el brote OR=15 (IC=1-482 p 0.027 S. Otros factores como la edad y el peso fueron de confusión. En cuanto a la nutrición parenteral, se corroboró su implicación, porque al revisar de inmediato el proceso de nutrición parenteral se encontró que los productos sobrantes se estaban almacenando y reutilizando hasta por 30 días.

  1. Acción de las olas sobre comunidades epibentónicas asociadas a raíces de Rhizophora mangle (Linnaeus

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    García R. Camilo B.

    2007-12-01

    Full Text Available Se sugiere un nuevo método de censo para comunidades bentónicas sésiles que tiene en cuenta la epibiosis y la complejidad comunitaria. La distribución entre sitios y vertical de especies es examinada en sitios con alto y bajo oleaje. Se examina como el oleaje determina mecanismos como el reclutamiento y algunas interacciones bióticas. Se relacionan estos mecanismos con la distribución vertical de las especies en las porciones de la raíz de mangle que están en el intermareal y en el submareal. Se propone un esquema idealizado de distribución vertical de especies para sitios con alto y bajo oleaje. La dinámica a pequeña escala fue examinada en huecos naturales de la biota sésil en las raíces de manglar. La recolonización de los huecos fue examinada y se relacionó con la teoría. La supervivencia de adultos, reclutas, organismos solitarios y coloniales fue examinada experimentalmente. Con la información experimental de la recolonización de los huecos y la supervivencia se examinaron las propiedades comunitarias de las comunidades naturales asociadas
    con raíces de Rhizophora mangle. Se relacionaron las propiedades comunitarias con la hipótesis del distur-bio
    intermedio. Se examinó experimentalmente la sucesión haciendo énfasis en el reemplazo direccional de especies. Se presentan las características de las comunidades en sitios con alto y bajo oleaje.

  2. Variables asociadas al inicio del consumo de cigarrillo en adolescentes estudiantes de básica secundaria de los colegios ofi ciales de la ciudad de Cartagena, Colombia

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    Zuleima Cogollo-Milanés

    2014-01-01

    Full Text Available Objetivo: determinar la prevalencia y las variables asociadas al inicio del consumo de cigarrillo en adolescentes de media vocacional de Cartagena, Colombia. Materiales y método: estudio analítico observacional transversal con 1.100 estudiantes de básica secundaria de las instituciones educativas oficiales de la ciudad de Cartagena, matriculados durante el año 2012; la información se recolectó a través de la ficha demográfica, el inventario de consumo de cigarrillo y actitudes frente al mismo de la Encuesta Mundial Sobre Tabaquismo en jóvenes (Emta_Joven, la escala Apgar familiar, Rosenberg para autoestima y la escala de Zung de ansiedad. Se realizó análisis esta- dístico univariado, bivariado y multivariado. Resultados: participaron 1.090 estudiantes (de los 1.100 fueron descartados 10 por estar mal diligenciados con edades entre 10 y 18 años, media = 12,3; 565 (51,8 % estudiantes fueron de sexo masculino y 525 (48,2 % de sexo femenino. El consumo de cigarrillo alguna vez en la vida se asoció a edades entre 13 y 18 años (OR = 2,86; IC95 % : 1,96-4,18, ser de sexo masculino (OR = 2,40; IC95 % : 1,63-3,56 y a alta intención de consumo de sustancias (cigarrillo, alcohol y marihuana (OR = 3,18; IC95 % : 2,18-4,64. Conclusión: el consumo de cigarrillo alguna vez en la vida en estudiantes de media vocacional de Cartagena, Colombia, se asoció a tener alta intención de consumo de sustancias, ser adolescente y ser de sexo masculino.

  3. [Genetic resources of nodule bacteria].

    Science.gov (United States)

    Rumiantseva, M L

    2009-09-01

    Nodule bacteria (rhizobia) form highly specific symbiosis with leguminous plants. The efficiency of accumulation of biological nitrogen depends on molecular-genetic interaction between the host plant and rhizobia. Genetic characteristics of microsymbiotic strains are crucial in developing highly productive and stress-resistant symbiotic pairs: rhizobium strain-host plant cultivar (species). The present review considers the issue of studying genetic resources of nodule bacteria to identify genes and their blocks, responsible for the ability of rhizobia to form highly effective symbiosis in various agroecological conditions. The main approaches to investigation of intraspecific and interspecific genetic and genomic diversity of nodule bacteria are considered, from MLEE analysis to the recent methods of genomic DNA analysis using biochips. The data are presented showing that gene centers of host plants are centers of genetic diversification of nodule bacteria, because the intraspecific polymorphism of genetic markers of the core and the accessory rhizobial genomes is extremely high in them. Genotypic features of trapped and nodule subpopulations of alfalfa nodule bacteria are discussed. A survey of literature showed that the genomes of natural strains in alfalfa gene centers exhibit significant differences in genes involved in control of metabolism, replication, recombination, and the formation of defense response (hsd genes). Natural populations of rhizobia are regarded as a huge gene pool serving as a source of evolutionary innovations.

  4. IDENTIFICATION OF BACTERIA IN LATEX PAINTS

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    Rojas, J.

    2008-01-01

    Full Text Available The bacteria are prokaryote organisms with a high capacity to colonize many types of habits. This research was developed with the object to identify extremophiles bacteria presents in latex paint. The bacteria were cultivated in culture mediums TSA, Blood Agar, Mc Conkey and finally the biochemical proof API-NF® for bacteria's isolation and identification, respectively. Characterization showed bacterial profile of Pasteurella sp. Hypothesis that could be found extremophiles bacteria in latex paint were demonstrated.

  5. Methylotrophic bacteria in sustainable agriculture.

    Science.gov (United States)

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices. PMID:27263015

  6. Methylotrophic bacteria in sustainable agriculture.

    Science.gov (United States)

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices.

  7. Chitin Degradation In Marine Bacteria

    DEFF Research Database (Denmark)

    Paulsen, Sara; Machado, Henrique; Gram, Lone

    2015-01-01

    Introduction: Chitin is the most abundant polymer in the marine environment and the second most abundant in nature. Chitin does not accumulate on the ocean floor, because of microbial breakdown. Chitin degrading bacteria could have potential in the utilization of chitin as a renewable carbon...... and nitrogen source in the fermentation industry.Methods: Here, whole genome sequenced marine bacteria were screened for chitin degradation using phenotypic and in silico analyses.Results: The in silico analyses revealed the presence of three to nine chitinases in each strain, however the number of chitinases...... chitin regulatory system.Conclusions: This study has provided insight into the ecology of chitin degradation in marine bacteria. It also served as a basis for choosing a more efficient chitin degrading production strain e.g. for the use of chitin waste for large-scale fermentations....

  8. Adaptation, Bacteria and Maxwell's Demons

    Science.gov (United States)

    Galajda, Peter; Keymer, Juan E.; Austin, Robert H.

    2007-03-01

    We propose a method to study the adaptation of bacterial populations with an asymmetric wall of Maxwell Demon openings. A Maxwell Demon opening is a funnel which is easier to enter than to leave. The interaction of swimming cells with such a Maxwell Demon Wall results in a population density separation, in apparent (but not real) violation of the Second Law of Thermodynamics, as we will show. Bacteria can be exposed to spatial challenges in order to move to e. g. higher food levels. The question we address in these experiments is: do the bacteria adapt and overcome the Maxwell Demon Wall?

  9. ANÁLISIS FILOGENÉTICO DE LA DIVERSIDAD BACTERIANA ASOCIADA A LA RIZÓSFERA DE PLANTAS DE TRIGO (Triticum aestivum L.)

    OpenAIRE

    Velázquez Sepúlveda, Itzi

    2012-01-01

    El estudio del suelo se considera enorme ya que este alberga una gran diversidad genética microbiana. En particular, la porción de suelo que rodea a la raíz vegetal se le conoce como rizósfera y es aquí donde existen diferentes interacciones entre los microorganismos y la planta. La composición de la comunidad microbiana, y en particular las bacterias de la rizósfera puede verse influenciada por diversos factores bióticos y abióticos. Se sabe que las bacterias juegan diverso...

  10. Manipulating Genetic Material in Bacteria

    Science.gov (United States)

    1998-01-01

    Lisa Crawford, a graduate research assistant from the University of Toledo, works with Laurel Karr of Marshall Space Flight Center (MSFC) in the molecular biology laboratory. They are donducting genetic manipulation of bacteria and yeast for the production of large amount of desired protein. Photo credit: NASA/Marshall Space Flight Center (MSFC)

  11. Engineering robust lactic acid bacteria

    NARCIS (Netherlands)

    Bron, P.A.; Bokhorst-van de Veen, van H.; Wels, M.; Kleerebezem, M.

    2011-01-01

    For centuries, lactic acid bacteria (LAB) have been industrially exploited as starter cultures in the fermentation of foods and feeds for their spoilage-preventing and flavor-enhancing characteristics. More recently, the health-promoting effects of LAB on the consumer have been widely acknowledged,

  12. DIVERSIDAD DE BACTERIAS ENDÓFITAS ASOCIADASA RAÍCES DEL PASTO COLOSUANA (Bothriochloa pertusaEN TRES LOCALIDADES DEL DEPARTAMENTODE SUCRE, COLOMBIA. Endophytes Diversity of Bacteria Associated with Rootsof Colosuana (Bothriochloa pertusa Pasture in Three Locationsof Sucre Department, Colombia.

    Directory of Open Access Journals (Sweden)

    ALEXANDER PEREZ C

    Full Text Available El objetivo del presente trabajo fue aislar diversidad de bacterias endófitas cultivables asociadas a raíces del pasto colosuana Bothriochloa pertusa (L A. Camus en tres localidades del departamento de Sucre, Colombia. La diversidad de bacterias endófitas fue realizada mediante el aislamiento de colonias en medios de cultivos. La densidad poblacional fue estimada por conteo directo de colonias en placa y las características culturales de cada morfotipo fueron obtenidas mediante observación de cada colonia formada. Se determinó la correlación diversidad, densidad poblacional y localidades, utilizando ANOVA y análisis de componentes principales o de correspondencia simple, mediante el programa estadístico R, 2009 (4,5. Fueron muestreadas 20 fincas por lo-calidad; se observó presencia de diversos morfotipos de bacterias endófitas. Se encontró diferencias significativas entre diversidad (morfotipos, densidad poblacional (UFC. raíz-1 y localidades. La diversidad de bacterias endófitas representa apenas una pequeña fracción de la diversidad total existente en la naturaleza, siendo escasas las informaciones que se tienen de la presencia de estos microorganismos en agroecosistemas específicos, razón por lo cual este trabajo se convierte en la primera evidencia de asociación entre bacterias endófitas y raíces del pasto colosuana en Colombia.The objective of this study was to isolate endophytes diversity of culturable bacteria associated with grass roots colosuana Bothriochloa pertusa (L A. Camus in three localities of the department of Sucre, Colombia. Endophytes bacterial diversity was performed by isolation of colonies on media culture. The population density was estimated by direct counting of colonies on plate and cultural characteristics of each morphotype were obtained by observation of each colony made. We determined the correlation diversity, population density and locations, using ANOVA and principal component analysis or

  13. Aplicación del Programa de Detección Precoz de Hipoacusia Neonatal para el diagnóstico del Sindrome de Usher y otras enfermedades asociadas a la hipoacusia congénita

    OpenAIRE

    Sotoca Fernández, Jorge Víctor

    2014-01-01

    La hipoacusia o afectación en la capacidad auditiva es el déficit sensorial más frecuente en el ser humano. El desarrollo de programas de detección precoz de hipoacusia neonatal ha permitido el tratamiento de pacientes en la etapa prelingual, evitándose posteriores problemas en la comunicación oral. La hipoacusia en un neonato puede presentarse de forma aislada o asociada a otras patologías. Por ello, el diagnóstico etiológico es una parte importante en la implementación de estos programas y ...

  14. Estudio controlado de factores de riesgo y variables clínicas asociadas al desarrollo de un trastorno de la conducta alimentaria en una muestra de primeros episodios de la Comunidad de Cantabria

    OpenAIRE

    González Gómez, Jana

    2016-01-01

    Los trastornos de la conducta alimentaria se han convertido en los países desarrollados en un problema de salud pública, tanto por la gravedad de la enfermedad en sí misma, como por su duración, el perfil de pacientes que lo padecen y las altas tasas de morbilidad asociadas. Las medidas desarrolladas para controlar el impacto de estos trastornos persiguen el objetivo de aumentar el conocimiento de la enfermedad y de este modo poder desarrollar programas de prevención, para ello es imprescind...

  15. Accesibilidad en el proceso de admisión a la Universidad de Costa Rica, de la población estudiantil con necesidades educativas especiales asociadas o no a discapacidad

    OpenAIRE

    Laura Stiller González; Martha Gross Martínez

    2012-01-01

    En el presente artículo se identifican aspectos conceptuales y pragmáticos del acceso al proceso de admisión a la Universidad de Costa Rica. Se rescata el marco legal y las acciones que fortalecen la inclusión a la educación superior. Se visualiza el papel de la Universidad de Costa Rica, en sus esfuerzos por hacer efectiva una universidad inclusiva, con alternativas y propuestas acordes a los requerimientos de la población estudiantil con necesidades educativas especiales asociadas o no a di...

  16. Desequilibrios metabólicos con especial referencia a las carenciales de minerales asociadas a problemas reproductivos en vacas lecheras de Cuba (Metabolic imbalances and minerals deficiencies associated with reproductive disorders in dairy cattle in Cuba

    Directory of Open Access Journals (Sweden)

    García Díaz, Juan R

    2011-12-01

    Full Text Available ResumenEl objetivo de este estudio fue diagnosticar los principales desequilibrios metabólicos con especial referencia a las carenciales de minerales asociadas a los problemas reproductivos en vacas lecheras mestizas Holstein x Cebú en un sistema de producción con amamantamiento restringido en la región central de Cuba.SummaryThe objective of this study was to diagnose the principal metabolic imbalances and deficiencies associated with reproductive disorders especially due to mineral deficiency in crossbreed (Holstein × Cebu dairy cows under restrained system of production in the central region of Cuba.

  17. Estructura espacial y estacional de la comunidad de hongos asociada al abrigo de hojas muertas de Espeletia grandiflora H & B en el páramo El Granizo, Monserrate - Cundinamarca, Colombia

    OpenAIRE

    Anacona Chicangana Amalfy; Sabogal Sandra Patricia

    2002-01-01

    RESUMENSe caracterizó la comunidad de hongos asociada a la necromasa de Espeletia grandiflora, segúnlas siguientes variables: Grado de descomposición de la necromasa, segmentos foliares,tamaño de la planta y época climática. El muestreo se realizó durante los meses marzo - abril(seca-húmeda), agosto (seca) y octubre (húmeda) del año 2001. Las muestras de roseta y denecromasa a diferentes alturas con respecto al suelo (distribución vertical), fueron subdivididasen secciones foliares (distribuc...

  18. Neumonía asociada a la ventilación mecánica en el postoperatorio de pacientes sometidos a cirugía cardiaca mayor: estudios paneuropeos (ESGNI 007, 008, 009)

    OpenAIRE

    Hortal Iglesias, Francisco Javier

    2012-01-01

    El primer objetivo de esta tesis es determinar la incidencia y tipo de infecciones nosocomiales en pacientes sometidos a cirugía cardiaca mayor en Europa. Valorar la proporción que representa la infección del tracto respiratorio inferior con respecto al total de las infecciones, así como las prácticas más comunes con respecto al diagnóstico y el tratamiento de la neumonía asociada a la ventilación mecánica (estudio ESGNI 007). El segundo objetivo es determinar la prevalencia de infeccio...

  19. Fuzzy species among recombinogenic bacteria

    Directory of Open Access Journals (Sweden)

    Fraser Christophe

    2005-03-01

    Full Text Available Abstract Background It is a matter of ongoing debate whether a universal species concept is possible for bacteria. Indeed, it is not clear whether closely related isolates of bacteria typically form discrete genotypic clusters that can be assigned as species. The most challenging test of whether species can be clearly delineated is provided by analysis of large populations of closely-related, highly recombinogenic, bacteria that colonise the same body site. We have used concatenated sequences of seven house-keeping loci from 770 strains of 11 named Neisseria species, and phylogenetic trees, to investigate whether genotypic clusters can be resolved among these recombinogenic bacteria and, if so, the extent to which they correspond to named species. Results Alleles at individual loci were widely distributed among the named species but this distorting effect of recombination was largely buffered by using concatenated sequences, which resolved clusters corresponding to the three species most numerous in the sample, N. meningitidis, N. lactamica and N. gonorrhoeae. A few isolates arose from the branch that separated N. meningitidis from N. lactamica leading us to describe these species as 'fuzzy'. Conclusion A multilocus approach using large samples of closely related isolates delineates species even in the highly recombinogenic human Neisseria where individual loci are inadequate for the task. This approach should be applied by taxonomists to large samples of other groups of closely-related bacteria, and especially to those where species delineation has historically been difficult, to determine whether genotypic clusters can be delineated, and to guide the definition of species.

  20. Alternativas de tratamiento para la osteonecrosis de los maxilares asociada a bisfosfonatos Treatment alternatives for bisphosphonate associated osteonecrosis of the jaw

    Directory of Open Access Journals (Sweden)

    C.M. Ardila Medina

    2010-06-01

    Full Text Available Se ha notificado recientemente un incremento de la osteonecrosis en los pacientes que reciben bisfosfonatos que contienen nitrógeno. Clínicamente, la necrosis ósea maxilar o mandibular puede ocurrir de forma espontánea o aparecer secundariamente a una exodoncia o trauma que afecte los maxilares. La necrosis se manifiesta por exposición del hueso en el sitio afectado, inflamación de los tejidos blandos adyacentes, halitosis, dolor y fiebre; puede producir fístula mucosa o cutánea. También se observa que los pacientes tratados con administración intravenosa de bisfosfonatos se encuentran en alto riesgo de desarrollar focos osteonecróticos únicos o múltiples, situación advertida esporádicamente en los sujetos tratados con administración oral. Se han indicado diferentes recomendaciones con el fin de establecer los procedimientos efectivos para tratar la osteonecrosis asociada a bisfosfonatos. Los tratamientos comprenden alternativas no quirúrgicas, antibióticos, terapia hiperbárica, cirugía convencional o mediante láser. Adicionalmente, las medidas preventivas son un aspecto importante que debe tenerse en cuenta.A relative increase in osteonecrosis has been reported in recent years particularly among patients receiving nitrogen-containing bisphosphonates. Clinically, mandibular or maxillary necrosis may occur spontaneously or be secondary to tooth extraction or trauma affecting the jaws. Necrosis typically manifests itself with exposure of the bone at the site involved and swelling of the adjacent soft tissues, halitosis, pain and fever, and may produce cutaneous or mucosal fistulae. It has also been observed that patients who have taken bisphosphonates by intravenous administration appear to be at a higher risk of developing single or multiple osteonecrotic foci of the jaw bones, whereas this has only been reported sporadically in patients with oral administration Several recommendations have been made to establish effective

  1. Aspectos de no calidad en neumonía asociada al uso de ventilador en una Unidad de Cuidados Intensivos de Medellín, 2012

    Directory of Open Access Journals (Sweden)

    Ariel Orozco-Arbeláez

    2016-02-01

    Full Text Available Resumen Objetivo: explorar los aspectos de no calidad en la atención clínica de pacientes con neumonia asociada al uso del ventilador (nav en una Unidad de Cuidados Intesivos de adultos en Medellín. Metodología: se desarrolló una investigación de enfoque cualitativo empleando como estrategia el estudio de caso y adoptando como fuente de categorías analíticas el Modelo Organizacional de Causalidad y Eventos Adversos de Reason bajo condiciones de operación institucional no controlables por el equipo investigador. Resultados: durante la fase analítica, a través de la codificación abierta, se identificaron 441 códigos en las entrevistas y 25 en las historias clínicas. Se reorganizaron mediante codificación axial en 14 subcategorías y 4 categorías analíticas, encontrando que una decisión de la gerencia (límites a la contratación de personal idóneo para el cuidado de la vía aérea de los pacientes sometidos a ventialción mecánicaa y su reemplazo por personal auxiliar fue percibida como un factor determinante para la generación de condiciones propicias para la incidencia de nav, aun en presencia de un enfoque pertinente y de sólidas barreras de seguridad. Abstract Objective: to explore non quality issues in the clinical care of patients with ventilator-associated pneumonia (vap in an adult Intensive Care Unit in Medellin, Colombia. Methodology: a qualitative study using the case study strategy. Reason’s Organizational Model of Causality and Adverse Events was used as the source for analytical categories and the hospital operating conditions were not controllable by the research team. Results: during the analytical phase, through open coding, 441 codes were identified from interviews and 25 from medical records. They were reorganized by axial coding into 14 subcategories and 4 analytical categories. It was found that a management decision (limiting the hiring of qualified staff to take care of patients’ airways with

  2. Complicaciones hepatobiliares asociadas a la Nutrición Parenteral Domiciliaria (NPD Home-based parenteral nutrition (HBPN-associated hepatobiliary complications

    Directory of Open Access Journals (Sweden)

    C. Martínez Faedo

    2011-06-01

    Full Text Available La Nutrición Parenteral Domiciliaria (NPD permite recuperar o mantener el estado nutricional de los pacientes con insuficiencia intestinal crónica que no pueden cubrir sus requerimientos nutricionales por vía digestiva. Es frecuente que a lo largo del tratamiento aparezcan alteraciones de la función hepática que, en los casos más graves y sobretodo en niños prematuros y de bajo peso, pueden condicionar un fallo hepático irreversible. La correcta composición de la bolsa de nutrición parenteral, evitando un excesivo aporte de energía, junto con el uso de nuevos tipos de emulsiones lipídicas (con menor contenido en ácidos grasos de la serie ω-6 y exentas de fitosteroles así como la utilización, aunque sea mínima, de la vía digestiva pueden contribuir a disminuir la aparición de la hepatopatía asociada a la NPD. Es imprescindible realizar controles periódicos clínicos y analíticos para detectar precozmente las alteraciones de la función hepática con objeto de realizar los cambios adecuados en el tratamiento y valorar la indicación de un posible trasplante intestinal antes de que el fallo hepático sea irreversible.Home-based parenteral nutrition (HBPN allows recovering or maintaining the nutritional status of patients with chronic intestinal failure that cannot afford their nutritional requirements through the digestive route. Frequently, liver function impairments develop along the treatment, which in the most severe cases, and especially in premature and low-weight infants, may lead to an irreversible liver failure. The proper composition of the parenteral nutrition bag, avoiding an excess of energy intake, together with the use of new types of lipid emulsions (with lower content in -6 fatty acids and voided of phytosterols as well as the use, although being minimal, of the enteral route, may contribute to a decrease in the occurrence of HBPN-associated liver disease. It is necessary to perform monthly clinical and

  3. Neuroplasticidad asociada a miembro fantasma

    Directory of Open Access Journals (Sweden)

    R. de la Puerta Huertas

    2014-12-01

    Full Text Available En las últimas décadas, el concepto de neuroplasticidad ha tomado clara relevancia asociado a la salud del paciente y al aprendizaje y conducta en el individuo sano. Esta capacidad del sistema nervioso implica asimilación, reorganización y modificación de nuestro mecanismo biológico, bioquímico y fisiológico. Con el advenimiento de nuevas tecnologías científicas que han aparecido en los últimos años, respondemos y mantenemos a este concepto de plasticidad del sistema nervioso como premisa base de ser susceptible a cambios externos y dinámicos. La experiencia del miembro fantasma pone al descubierto, de forma permanente, la existencia de un mapa corporal mental que subyace y modifica la experiencia con nuestro cuerpo, cuyo sistema nervioso posee la capacidad de reorganización cortical por estimulación sensitiva, sensorial, endocrina y motora. La relación entre miembro fantasma y neuroplasticidad es compleja, difícil de investigar a pesar de los avances científicos obtenidos y, a la vez, es dinámica, ya que esta capacidad responde a las necesidades de salud en el ser humano en las diferentes etapas de su vida.

  4. Physico-chemical factors and bacteria in fish ponds

    OpenAIRE

    Jun, X.; Xiuzheng, F.; Tongbing, Y.

    2000-01-01

    Analyses of pond water and mud samples show that nitrifying bacteria (including ammonifying bacteria, nitrite bacteria, nitrobacteria and denitrifying bacteria) are in general closely correlated with various physico-chemical factors, ammonifying bacteria are mainly correlated with dissolved oxygen; denitrifying bacteria are inversely correlated with phosphorus; nitrite bacteria are closely correlated with nitrites, nitrobacteria are inversely correlated with ammoniac nitrogen. The nitrifying ...

  5. Smokeless Tobacco May Contain Potentially Harmful Bacteria

    Science.gov (United States)

    ... 160769.html Smokeless Tobacco May Contain Potentially Harmful Bacteria Infections, diarrhea and vomiting are possible consequences, FDA ... products can harbor several species of potentially harmful bacteria, researchers warn. Two types in particular -- Bacillus licheniformis ...

  6. Genetics of Lactic Acid Bacteria

    Science.gov (United States)

    Zagorec, Monique; Anba-Mondoloni, Jamila; Coq, Anne-Marie Crutz-Le; Champomier-Vergès, Marie-Christine

    Many meat (or fish) products, obtained by the fermentation of meat originating from various animals by the flora that naturally contaminates it, are part of the human diet since millenaries. Historically, the use of bacteria as starters for the fermentation of meat, to produce dry sausages, was thus performed empirically through the endogenous micro-biota, then, by a volunteer addition of starters, often performed by back-slopping, without knowing precisely the microbial species involved. It is only since about 50 years that well defined bacterial cultures have been used as starters for the fermentation of dry sausages. Nowadays, the indigenous micro-biota of fermented meat products is well identified, and the literature is rich of reports on the identification of lactic acid bacteria (LAB) present in many traditional fermented products from various geographical origin, obtained without the addition of commercial starters (See Talon, Leroy, & Lebert, 2007, and references therein).

  7. Aggregation Patterns in Stressed Bacteria

    CERN Document Server

    Tsimring, L S; Aranson, I S; Ben-Jacob, E; Cohen, I; Shochet, O; Tsimring, Lev; Levine, Herbert; Aranson, Igor; Ben-Jacob, Eshel; Cohen, Inon; Shochet, Ofer

    1995-01-01

    We study the formation of spot patterns seen in a variety of bacterial species when the bacteria are subjected to oxidative stress due to hazardous byproducts of respiration. Our approach consists of coupling the cell density field to a chemoattractant concentration as well as to nutrient and waste fields. The latter serves as a triggering field for emission of chemoattractant. Important elements in the proposed model include the propagation of a front of motile bacteria radially outward form an initial site, a Turing instability of the uniformly dense state and a reduction of motility for cells sufficiently far behind the front. The wide variety of patterns seen in the experiments is explained as being due the variation of the details of the initiation of the chemoattractant emission as well as the transition to a non-motile phase.

  8. Dissipative Shocks behind Bacteria Gliding

    CERN Document Server

    Virga, Epifanio G

    2014-01-01

    Gliding is a means of locomotion on rigid substrates utilized by a number of bacteria includingmyxobacteria and cyanobacteria. One of the hypotheses advanced to explain this motility mechanism hinges on the role played by the slime filaments continuously extruded from gliding bacteria. This paper solves in full a non-linear mechanical theory that treats as dissipative shocks both the point where the extruded slime filament comes in contact with the substrate, called the filament's foot, and the pore on the bacterium outer surface from where the filament is ejected. We prove that kinematic compatibility for shock propagation requires that the bacterium uniform gliding velocity (relative to the substrate) and the slime ejecting velocity (relative to the bacterium) must be equal, a coincidence that seems to have already been observed.

  9. LACTIC ACID BACTERIA: PROBIOTIC APPLICATIONS

    Directory of Open Access Journals (Sweden)

    NEENA GARG

    2015-10-01

    Full Text Available Lactic acid bacteria (LAB is a heterotrophic Gram-positive bacteria which under goes lactic acid fermentations and leads to production of lactic acid as an end product. LAB includes Lactobacillus, Leuconostoc, Pediococcus, Lactococcus and Streptococcus which are grouped together in the family lactobacillaceae. LAB shows numerous antimicrobial activities due to production of antibacterial and antifungal compounds such as organic acids, bacteriocins, diacetyl, hydrogen peroxide and reutrin. LAB are used as starter culture, consortium members and bioprotective agents in food industry that improve food quality, safety and shelf life. A variety of probiotic LAB species are available including Lactobacillus acidophilus, L. bulgaricus, L. lactis, L. plantarum, L. rhamnosus, L. reuteri, L. fermentum, Bifidobacterium longum, B. breve, B. bifidum, B. esselnsis, B. lactis, B. infantis that are currently recommended for development of functional food products with health-promoting capacities.

  10. Re-engineering bacteria for ethanol production

    Science.gov (United States)

    Yomano, Lorraine P; York, Sean W; Zhou, Shengde; Shanmugam, Keelnatham; Ingram, Lonnie O

    2014-05-06

    The invention provides recombinant bacteria, which comprise a full complement of heterologous ethanol production genes. Expression of the full complement of heterologous ethanol production genes causes the recombinant bacteria to produce ethanol as the primary fermentation product when grown in mineral salts medium, without the addition of complex nutrients. Methods for producing the recombinant bacteria and methods for producing ethanol using the recombinant bacteria are also disclosed.

  11. IDENTIFICATION OF BACTERIA IN LATEX PAINTS

    OpenAIRE

    Rojas, J

    2008-01-01

    The bacteria are prokaryote organisms with a high capacity to colonize many types of habits. This research was developed with the object to identify extremophiles bacteria presents in latex paint. The bacteria were cultivated in culture mediums TSA, Blood Agar, Mc Conkey and finally the biochemical proof API-NF® for bacteria's isolation and identification, respectively. Characterization showed bacterial profile of Pasteurella sp. Hypothesis that could be found extremophiles bac...

  12. Compartmentalization of bacteria in microcapsules.

    Science.gov (United States)

    van Wijk, Judith; Heunis, Tiaan; Harmzen, Elrika; Dicks, Leon M T; Meuldijk, Jan; Klumperman, Bert

    2014-12-18

    Lactobacillus plantarum strain 423 was encapsulated in hollow poly(organosiloxane) microcapsules by templating water-in-oil Pickering emulsion droplets via the interfacial reaction of alkylchlorosilanes. The bacteria were suspended in growth medium or buffer to protect the cells against pH changes during the interfacial reactions with alkylchlorosilanes. The results of this work open up novel avenues for the encapsulation of microbial cells.

  13. Folate Production by Probiotic Bacteria

    OpenAIRE

    Stefano Raimondi; Alberto Amaretti; Maddalena Rossi

    2011-01-01

    Probiotic bacteria, mostly belonging to the genera Lactobacillus and Bifidobacterium, confer a number of health benefits to the host, including vitamin production. With the aim to produce folate-enriched fermented products and/or develop probiotic supplements that accomplish folate biosynthesis in vivo within the colon, bifidobacteria and lactobacilli have been extensively studied for their capability to produce this vitamin. On the basis of physiological studies and genome analysis, wild-typ...

  14. Magnetotactic Bacteria from Extreme Environments

    OpenAIRE

    Lefèvre, Christopher T; Dennis A. Bazylinski

    2013-01-01

    Magnetotactic bacteria (MTB) represent a diverse collection of motile prokaryotes that biomineralize intracellular, membrane-bounded, tens-of-nanometer-sized crystals of a magnetic mineral called magnetosomes. Magnetosome minerals consist of either magnetite (Fe3O4) or greigite (Fe3S4) and cause cells to align along the Earth’s geomagnetic field lines as they swim, a trait called magnetotaxis. MTB are known to mainly inhabit the oxic–anoxic interface (OAI) in water columns or sediments of aqu...

  15. Characterization of Mediterranean Magnetotactic Bacteria

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Magnetotactic bacteria are a diverse group of motile prokaryotes that are ubiquitous in aquatic habitats and cosmopolitan in distribution. In this study, we collected magnetotactic bacteria from the Mediterranean Sea. A remarkable diversity of morphotypes was observed, including muiticellular types that seemed to differ from those previously found in North and South America. Another interesting organism was one with magnetosomes arranged in a six-stranded bundle which occupied one third of the cell width. The magnetosome bundle was evident even under optic microscopy. These cells were connected together and swam as a linear entire unit. Magnetosomes did not always align up to form a straight linear chain. A chain composed of rectangle magnetosomes bent at a position with an oval crystal. High resolution transmission electron microscopy analysis of the crystal at the pivotal position suggested uncompleted formation of the crystal. This is the first report of Mediterranean magnetotactic bacteria, which should be useful for studies of biogeochemical cycling and geohistory of the Mediterranean Sea.

  16. Laser-Based Identification of Pathogenic Bacteria

    Science.gov (United States)

    Rehse, Steven J.

    2009-01-01

    Bacteria are ubiquitous in our world. From our homes, to our work environment, to our own bodies, bacteria are the omnipresent although often unobserved companions to human life. Physicists are typically untroubled professionally by the presence of these bacteria, as their study usually falls safely outside the realm of our typical domain. In the…

  17. Nitrogen-fixing methane-utilizing bacteria

    NARCIS (Netherlands)

    Bont, de J.A.M.

    1976-01-01

    Methane occurs abundantly in nature. In the presence of oxygen this gas may be metabolized by bacteria that are able to use it as carbon and energy source. Several types of bacteria involved in the oxidation of methane have been described in literature. Methane-utilizing bacteria have in common that

  18. Drosophila lifespan enhancement by exogenous bacteria

    OpenAIRE

    Brummel, Ted; Ching, Alisa; Seroude, Laurent; Simon, Anne F.; Benzer, Seymour

    2004-01-01

    We researched the lifespan of Drosophila under axenic conditions compared with customary procedure. The experiments revealed that the presence of bacteria during the first week of adult life can enhance lifespan, despite unchanged food intake. Later in life, the presence of bacteria can reduce lifespan. Certain long-lived mutants react in different ways, indicating an interplay between bacteria and longevity-enhancing genes.

  19. Current strategies for improving food bacteria

    NARCIS (Netherlands)

    Kuipers, O P; Buist, Girbe; Kok, Jan

    2000-01-01

    Novel concepts and methodologies are emerging that hold great promise for the directed improvement of food-related bacteria, specifically lactic acid bacteria. Also, the battle against food spoilage and pathogenic bacteria can now be fought more effectively. Here we describe recent advances in micro

  20. Protective ileostomy: complications and mortality associated with its closure Ileostomías de protección: complicaciones y mortalidad asociadas a su cierre

    Directory of Open Access Journals (Sweden)

    Mónica Mengual-Ballester

    2012-07-01

    Full Text Available Introduction: diverting loop ileostomies are widely used in colorectal surgery to protect low rectal anastomoses. However, they may have various complications, among which are those associated with the subsequent stoma closure. The present study analyses our experience in a series of patients undergoing closure of loop ileostomies. Method: retrospective study of all the patients undergoing ileostomy closure at our hospital between 2006-2010. There were 89 patients: 56 males (63% and 33 females (37% with a mean age of 55 (38-71 years. The most common indication for ileostomy was protection of a low rectal anastomosis, 81 patients (91%. The waiting time until stoma closure, type and frequency of the complications, length of hospital stay and mortality rate are analysed. Results: waiting time before surgery was 8 (1-25 months. Forty-one patients (45,9% developed some type of complication, three were reoperated (3.37% and one patient died (1.12%. The most important complications were intestinal obstruction (32.6%, diarrhoea (6%, surgical wound infection (6%, enterocutaneous fistula (4.5%, rectorrhagia (3.4% and anastomotic leak (1.12%. The mean length of patient stay was 7.54 (2-23 days. Conclusions: protective ostomies in low rectal anastomoses have proved to be the only preventive measure for reducing the morbidity and mortality rates for anastomotic leakage. However, creation means subsequent closure, which must not be considered a minor procedure but an operation with possibly significant complications, including death, as has been shown in publications on the subject and in our own series.Introducción: las ileostomías derivativas son ampliamente utilizadas para proteger anastomosis rectales bajas. Sin embargo no están desprovistas de inconvenientes, como la posibilidad de presentar distintas complicaciones, entre las cuales figuran las asociadas al cierre ulterior del estoma. Analizamos nuestra experiencia en una serie de pacientes sometidos

  1. Osteonecrosis de los maxilares asociada al uso de bifosfonatos: revisión de ocho casos Bisphosphonate-related jaw osteonecrosis: Review of eight cases

    Directory of Open Access Journals (Sweden)

    J. Joshi Otero

    2011-03-01

    Full Text Available Introducción: A finales de 2003 se comienzan a publicar en forma creciente los primeros casos de exposición ósea en los maxilares con evolución tórpida, asociados al uso de bifosfonatos por vía intravenosa. Estos fármacos son usados en pacientes con osteoporosis, mieloma múltiple, hipercalcemia maligna y cáncer de pulmón, mama y próstata, principalmente por su capacidad de inhibir la resorción ósea. Material y método: Estudio prospectivo de los pacientes en el Hospital Virgen Macarena que presentaban lesiones maxilares asociadas al uso de bifosfonatos desde el año 2006 hasta la actualidad. Las variables que valoramos en el paciente son: sexo, edad, tratamiento con bifosfonatos, inicio de la osteonecrosis, relación con tratamientos dentales, tratamiento realizado y evolución. Resultados: Se estudiaron 8 pacientes con osteonecrosis maxilar secundaria a tratamiento con bifosfonatos intravenosos u orales por su patología previa oncológica u osteoporótica que fueron tratados según su estadio clínico-radiológico con antibioterapia, legrado y/o exéresis del secuestro según el caso. Presentamos los resultados con un seguimiento mínimo de 15 meses. Conclusiones: El aumento en la incidencia de la osteomielitis maxilar en los pacientes asociados al uso de bifosfonatos y la dificultad para su tratamiento hacen necesario establecer pautas terapéuticas estandarizadas. En nuestra experiencia, el tratamiento conservador basado en la antibioterapia además del legrado de la zona bajo anestesia local permite el control y la curación del proceso en algunos de los pacientes con OMRB grado II.Background: In late 2003, an increasing number of case reports began to appear on bone exposure of the jaw with a torpid evolution in association with intravenous bisphosphonate use. Bisphosphonates are used to inhibit bone resorption in patients with osteoporosis, multiple myeloma, hypercalcemia of malignancy, lung cancer, breast cancer and prostate

  2. Infección natural de chinches Triatominae con Trypanosoma cruzi asociadas a la vivienda humana en México Natural infection of Triatominae bugs in Mexican dwellings

    Directory of Open Access Journals (Sweden)

    Vianey Vidal-Acosta

    2000-11-01

    Full Text Available OBJETIVO: Informar el porcentaje de infección natural de las especies de triatóminos que habitan con mayor frecuencia el medio doméstico y peridoméstico en México, así como dar a conocer las localidades de colecta por estado. MATERIAL Y MÉTODOS: Se recibieron muestras de chinches Triatominae en el Departamento de Entomología del Instituto de Diagnóstico y Referencia Epidemiológicos, para su determinación taxonómica y la búsqueda parasitoscópica de Trypanosoma cruzi, provenientes de 14 estados del país, de enero de 1993 a diciembre de 1999. Se analizaron en conjunto los resultados obtenidos en esos años. RESULTADOS: De una muestra de 5 399 ejemplares, fueron 13 las especies de triatóminos asociadas a las viviendas. El porcentaje de infección natural tuvo una amplia variación entre las especies. De las estudiadas, nueve se encontraron con infección natural; el mayor porcentaje de infección corresponde a Triatoma pallidipennis, T. picturata, Rhodnius prolixus y T. longipennis. Los estados con mayor porcentaje de infección fueron Nayarit, Morelos y Michoacán. Se presentaron nuevos registros estatales de Triatoma dimidiata, T. gerstaeckeri, T. longipennis, T. mexicana y T. pallidipennis y uno local de Pastrongylus rufotuberculatus. Además, se informa por primera vez la infección natural en algunas de ellas. CONCLUSIONES: Se debe poner mayor énfasis en el estudio de la biología y aspectos bionómicos de los triatóminos y realizar una vigilancia permanente para tener los registros de distribución actualizados, así como para conocer los índices de infección natural por T. cruzi, de las especies domiciliarias, peridomiciliarias y de las que están en proceso de adaptación a la vivienda humana.OBJECTIVE: To estimate the prevalence of infection with Trypanosoma cruzi in Triatominae species frequently found in and around Mexican dwellings, and to assess the frequency of Triatominae in towns by state. MATERIAL AND METHODS

  3. DETERMINACIÓN DE MEDIOS DE CULTIVO Y PH PARA LA MASIFICACIÓN in vitro DE CEPAS DE Suillus luteus Aubl. ASOCIADAS A Pinus radiata D. Don Y Scleroderma citrinum Pers. ASOCIADAS A Eucalyptus globulus Labill. DE LA REGIÓN DEL BIOBÍO, CHILE

    Directory of Open Access Journals (Sweden)

    Marta González

    2015-02-01

    Full Text Available El uso de agentes biológicos en la producción en vivero ha aflorado como un elemento que permite no sólo mejorar la calidad morfológica y fisiológica de las plantas, sino que también posibilitar un mayor éxito en el ámbito silvicultural de una plantación. Estos agentes biológicos requieren de un ambiente óptimo para crecer, asociarse y reproducirse. El objetivo de este estudio fue determinar la dependencia del pH y el medio de cultivo en el crecimiento in vitro de distintas cepas de Suillus luteus y Scleroderma citrinum asociadas a Pinus radiata y Eucalyptus globulus, respectivamente. El estudio se realizó en condiciones controladas de temperatura y humedad, disponiendo los inóculos en placas Petri con diferentes medios cultivo, evaluando parámetros de crecimiento y biomasa a los 38 días para S. luteus y 105 días para S. citrinum. Los resultados indican que tanto el medio de cultivo, el pH del medio, así como las cepas de cada especie estudiada, son determinantes en las respuestas de crecimiento de los hongos ectomicorrícicos in vitro evaluados. Las cepas de S. luteus se desarrollaron adecuadamente en un medio de cultivo con abundancia de nutrientes (BAF, MMN como en baja presencia de ellos (EMA, y con pH más bien ácido (4,8 y 5,8. Por otro lado, las cepas de S. citrinum presentaron, para los mismos ambientes, un desarrollo inferior y lento, no obstante, la cepa Sc8 se reprodujo de forma óptima y rápida bajo un medio de cultivo BAF y con un pH moderadamente ácido de 5,8.

  4. Potential role of bacteria packaging by protozoa in the persistence and transmission of pathogenic bacteria

    OpenAIRE

    Alix M Denoncourt; Paquet, Valérie E.; Charette, Steve J.

    2014-01-01

    Many pathogenic bacteria live in close association with protozoa. These unicellular eukaryotic microorganisms are ubiquitous in various environments. A number of protozoa such as amoebae and ciliates ingest pathogenic bacteria, package them usually in membrane structures, and then release them into the environment. Packaged bacteria are more resistant to various stresses and are more apt to survive than free bacteria. New evidence indicates that protozoa and not bacteria control the packaging...

  5. Programmed survival of soil bacteria

    DEFF Research Database (Denmark)

    Jensen, Lars Bogø; Molin, Søren; Sternberg, Claus;

    Biological containment systems have been developed for Pseudomonas putida and related soil bacteria. The systems are based on combinations of lethal genes and regulated gene expression. Two types of killing function have been employed: 1) A membrane protein interfering with the membrane potential...... (geJ). and 2) a nuclease attacking nucleic acids intracellularly. The efficacy of these lethal genes has been assessed in model constructions with a synthetic lac promoter. By combination with the regulatory pathway of the TOL genes. a system was designed which allows bacterial growth in the presence...

  6. Bacteria and vampirism in cinema.

    Science.gov (United States)

    Castel, O; Bourry, A; Thévenot, S; Burucoa, C

    2013-09-01

    A vampire is a non-dead and non-alive chimerical creature, which, according to various folklores and popular superstitions, feeds on blood of the living to draw vital force. Vampires do not reproduce by copulation, but by bite. Vampirism is thus similar to a contagious disease contracted by intravascular inoculation with a suspected microbial origin. In several vampire films, two real bacteria were staged, better integrated than others in popular imagination: Yersinia pestis and Treponema pallidum. Bacillus vampiris was created for science-fiction. These films are attempts to better define humans through one of their greatest fears: infectious disease. PMID:23916557

  7. Sewage-pollution indicator bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.; Rodrigues, V.; Alwares, E.; Rodrigues, C.; Baksh, R.; Jayan, S.; Mohandass, C.

    ?8 September 2002), and post-monsoon (12?15 March 2003). The schedule of observations is given in table 11.1. At each location, water samples were collected every three hours for 24 hours. The eight samples collected over a 24-hour period allowed us to examine..., small (less than 2 mm June 13, 2007 20:6 RPS rpb001ch11 SEWAGE-POLLUTION INDICATOR BACTERIA 117 Table 11.1 Sampling schedule followed for enumeration of bacterial populations during this study. Estuary Sampling dates Sampling strategy Mandovi 28?29 April...

  8. Bacteria and vampirism in cinema.

    Science.gov (United States)

    Castel, O; Bourry, A; Thévenot, S; Burucoa, C

    2013-09-01

    A vampire is a non-dead and non-alive chimerical creature, which, according to various folklores and popular superstitions, feeds on blood of the living to draw vital force. Vampires do not reproduce by copulation, but by bite. Vampirism is thus similar to a contagious disease contracted by intravascular inoculation with a suspected microbial origin. In several vampire films, two real bacteria were staged, better integrated than others in popular imagination: Yersinia pestis and Treponema pallidum. Bacillus vampiris was created for science-fiction. These films are attempts to better define humans through one of their greatest fears: infectious disease.

  9. Mecanismos moleculares de resistencia antibiótica en Escherichia coli asociadas a diarrea Molecular mechanisms of antibiotic resistance in Escherichia coli- associated diarrhea

    OpenAIRE

    Susan Mosquito; Joaquim Ruiz; José Luis Bauer; Ochoa, Theresa J.

    2011-01-01

    La resistencia antibiótica es un problema emergente a nivel mundial presente en diversas bacterias, en especial en la Escherichia coli, que tiene altos porcentajes de resistencia hacia ampicilina, trimetoprim-sulfametoxazol, tetraciclina, cloramfenicol y ácido nalidíxico, lo que supone grandes complicaciones en el tratamiento antibiótico cuando este es requerido. Este aumento de resistencia antibiótica se debe a la adquisición de diferentes mecanismos moleculares de resistencia mediante mutac...

  10. Evaluación y diseño de bacterias lácticas (BAL) de origen alimentario y de otros hospedadores como factorías celulares de producción de bacteriocinas

    OpenAIRE

    Jiménez Martínez, Juan José

    2015-01-01

    Las bacterias lácticas BAL constituyen un grupo microbiano muy interesante por sus características biotecnológicas asociadas a la producción de péptidos antimicrobianos, otros péptidos bioactivos, enzimas de utilización industrial y utilización como probióticos o por su posible utilización como factorías celulares de producción de proteínas, péptidos, enzimas y otros metabolitos de interés en la industria alimentaria o como terapeúticos en medicina humana y veterinaria y en producción animal....

  11. DMTB: the magnetotactic bacteria database

    Science.gov (United States)

    Pan, Y.; Lin, W.

    2012-12-01

    Magnetotactic bacteria (MTB) are of interest in biogeomagnetism, rock magnetism, microbiology, biomineralization, and advanced magnetic materials because of their ability to synthesize highly ordered intracellular nano-sized magnetic minerals, magnetite or greigite. Great strides for MTB studies have been made in the past few decades. More than 600 articles concerning MTB have been published. These rapidly growing data are stimulating cross disciplinary studies in such field as biogeomagnetism. We have compiled the first online database for MTB, i.e., Database of Magnestotactic Bacteria (DMTB, http://database.biomnsl.com). It contains useful information of 16S rRNA gene sequences, oligonucleotides, and magnetic properties of MTB, and corresponding ecological metadata of sampling sites. The 16S rRNA gene sequences are collected from the GenBank database, while all other data are collected from the scientific literature. Rock magnetic properties for both uncultivated and cultivated MTB species are also included. In the DMTB database, data are accessible through four main interfaces: Site Sort, Phylo Sort, Oligonucleotides, and Magnetic Properties. References in each entry serve as links to specific pages within public databases. The online comprehensive DMTB will provide a very useful data resource for researchers from various disciplines, e.g., microbiology, rock magnetism and paleomagnetism, biogeomagnetism, magnetic material sciences and others.

  12. Endophytic bacteria in Coffea arabica L.

    Science.gov (United States)

    Vega, Fernando E; Pava-Ripoll, Monica; Posada, Francisco; Buyer, Jeffrey S

    2005-01-01

    Eighty-seven culturable endophytic bacterial isolates in 19 genera were obtained from coffee plants collected in Colombia (n = 67), Hawaii (n = 17), and Mexico (n = 3). Both Gram positive and Gram negative bacteria were isolated, with a greater percentage (68%) being Gram negative. Tissues yielding bacterial endophytes included adult plant leaves, various parts of the berry (e.g., crown, pulp, peduncle and seed), and leaves, stems, and roots of seedlings. Some of the bacteria also occurred as epiphytes. The highest number of bacteria among the berry tissues sampled was isolated from the seed, and includes Bacillus , Burkholderia , Clavibacter , Curtobacterium , Escherichia , Micrococcus , Pantoea , Pseudomonas , Serratia , and Stenotrophomonas . This is the first survey of the endophytic bacteria diversity in various coffee tissues, and the first study reporting endophytic bacteria in coffee seeds. The possible role for these bacteria in the biology of the coffee plant remains unknown.

  13. Sulfur metabolism in phototrophic sulfur bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Dahl, Christiane

    2008-01-01

    in other types of anoxygenic phototrophic bacteria. The biochemistry and genetics of sulfur compound oxidation in PSB and GSB are described in detail. A variety of enzymes catalyzing sulfur oxidation reactions have been isolated from GSB and PSB (especially Allochromatium vinosum, a representative......Phototrophic sulfur bacteria are characterized by oxidizing various inorganic sulfur compounds for use as electron donors in carbon dioxide fixation during anoxygenic photosynthetic growth. These bacteria are divided into the purple sulfur bacteria (PSB) and the green sulfur bacteria (GSB......). They utilize various combinations of sulfide, elemental sulfur, and thiosulfate and sometimes also ferrous iron and hydrogen as electron donors. This review focuses on the dissimilatory and assimilatory metabolism of inorganic sulfur compounds in these bacteria and also briefly discusses these metabolisms...

  14. Endophytic bacteria in Coffea arabica L.

    Science.gov (United States)

    Vega, Fernando E; Pava-Ripoll, Monica; Posada, Francisco; Buyer, Jeffrey S

    2005-01-01

    Eighty-seven culturable endophytic bacterial isolates in 19 genera were obtained from coffee plants collected in Colombia (n = 67), Hawaii (n = 17), and Mexico (n = 3). Both Gram positive and Gram negative bacteria were isolated, with a greater percentage (68%) being Gram negative. Tissues yielding bacterial endophytes included adult plant leaves, various parts of the berry (e.g., crown, pulp, peduncle and seed), and leaves, stems, and roots of seedlings. Some of the bacteria also occurred as epiphytes. The highest number of bacteria among the berry tissues sampled was isolated from the seed, and includes Bacillus , Burkholderia , Clavibacter , Curtobacterium , Escherichia , Micrococcus , Pantoea , Pseudomonas , Serratia , and Stenotrophomonas . This is the first survey of the endophytic bacteria diversity in various coffee tissues, and the first study reporting endophytic bacteria in coffee seeds. The possible role for these bacteria in the biology of the coffee plant remains unknown. PMID:16187260

  15. Transformation of gram positive bacteria by sonoporation

    Science.gov (United States)

    Yang, Yunfeng; Li, Yongchao

    2014-03-11

    The present invention provides a sonoporation-based method that can be universally applied for delivery of compounds into Gram positive bacteria. Gram positive bacteria which can be transformed by sonoporation include, for example, Bacillus, Streptococcus, Acetobacterium, and Clostridium. Compounds which can be delivered into Gram positive bacteria via sonoporation include nucleic acids (DNA or RNA), proteins, lipids, carbohydrates, viruses, small organic and inorganic molecules, and nano-particles.

  16. Mortality of fecal bacteria in seawater.

    OpenAIRE

    Garcia-Lara, J.; Menon, P.; Servais, P; Billen, G.

    1991-01-01

    We propose a method for determining the mortality rate for allochthonous bacteria released in aquatic environments without interference due to the loss of culturability in specific culture media. This method consists of following the disappearance of radioactivity from the trichloroacetic acid-insoluble fraction in water samples to which [3H]thymidine-prelabeled allochthonous bacteria have been added. In coastal seawater, we found that the actual rate of disappearance of fecal bacteria was 1 ...

  17. Exploitation of host lipids by bacteria

    OpenAIRE

    Vromman, François; Subtil, Agathe

    2014-01-01

    International audience; Bacteria that interact with eukaryotic cells have developed a variety of strategies to divert host lipids, or cellular processes driven by lipids, to their benefit. Host lipids serve as building blocks for bacterial membrane formation and as energy source. They promote the formation of specific microdomains, facilitating interactions with the host. Host lipids are also critical players in the entry of bacteria or toxins into cells, and, for bacteria growing inside para...

  18. Cuestiones asociadas a la propuesta de catalogación en línea. La construcción, distribución y recepción del audiovisual en el entorno multimedia.

    Directory of Open Access Journals (Sweden)

    Paz Sastre Domínguez

    2012-04-01

    Full Text Available Contrasta los planteamientos del artículo “Museografía, Diseño y Videoarte: Propuesta de catalogación en línea” con proyectos de similares características disponibles en la Red, ampliando así los resultados anteriores mediante la reflexión acerca de las problemáticas asociadas a la construcción, distribución y recepción de las obras audiovisuales en los entornos multimedia: cómo definir y clasificar las nuevas prácticas audiovisuales, la propiedad intelectual en el entorno multimedia y las posibilidades de la exhibición en Red de las obras.

  19. Hemorragias intracraneales de carácter evitable asociadas a anticoagulantes orales en pacientes con fibrilación auricular Avoidable intracranial hemorrhages associated with oral anticoagulants in patients with atrial fibrillation

    Directory of Open Access Journals (Sweden)

    A. García Luque

    2011-12-01

    Full Text Available Introducción y objetivo: El aumento de la prescripción de anticoagulantes orales ha provocado un aumento de hemorragias intracraneales, la reacción adversa más grave asociada a este grupo farmacológico. El objetivo del estudio es evaluar el carácter evitable de hemorragias intracraneales asociada a anticoagulantes orales que causan ingreso hospitalario en pacientes con fibrilación auricular. Método: Supervisión de las historias clínicas de los pacientes que ingresaron en los Hospitales Universitarios Virgen del Rocío (01/01/03 al 31/03/07 con hemorragia intracraneal y fibrilación auricular; considerando hemorragia intracraneal asociada a anticoagulantes orales aquellas con una relación ≥ posible al aplicar el algoritmo de causalidad del Sistema Español de Farmacovigilancia. Para valorar el carácter evitable de la hemorragia intracraneal se ha estudiado la relación beneficio/riesgo del uso de anticoagulantes orales. Resultados: Al menos 20/57 (35,1% hemorragias intracraneales asociadas a anticoagulantes orales pudieron ser potencialmente evitables, de las cuales en 7/20 (35% el desenlace fue mortal, presentando secuelas 8/13 (61,5% de los supervivientes. El fármaco sospechoso de interaccionar con anticoagulantes orales referenciado con mayor frecuencia fue el omeprazol, 11/57 (19%, a pesar de estar documentada esta interacción como altamente probable en la Bibliografía y en los protocolos del Hospital. Conclusiones: La relación beneficio/riesgo del uso de anticoagulantes orales, el control estricto del Índice Normalizado Internacional, junto con las posibles interacciones medicamentosas deben ser evaluadas de forma individualizada y periódicamente para minimizar el riesgo de hemorragia intracraneal, que en un porcentaje elevado de casos es una reacción adversa potencialmente evitable y mortal.Introduction and objectives: The increase in oral anticoagulants prescription has caused an increase in intracranial hemorrhages

  20. Influencia del microhábitat sobre la obtención y actividad de bacterias biotransformadoras de carbón de bajo rango

    Directory of Open Access Journals (Sweden)

    Rodríguez Luz Nidia

    2012-08-01

    Full Text Available Se aislaron bacterias con actividad biotransformadora de carbón de bajo rango (CBR a partir de muestras ambientales con presencia de residuos de carbón en la mina “El Cerrejón”. Se aislaron 75 morfotipos bacterianos de los cuales 32 presentaron crecimiento en medio sólido mínimo de sales con carbón al 5%. Se diseño un protocolo para la selección de los morfotipos con mayor actividad biotransformadora de CBR, el protocolo incluye el aislamiento en un medio selectivo con CBR en polvo, pruebas cualitativas y cuantitativas de solubilización de CBR en medios sólidos y líquido. El mecanismo de solubilización en las cepas que producen mayores valores de sustancias húmicas (SH está asociada a cambios de pH en el medio, debido probablemente a la producción de sustancias alcalinas extracelulares por las bacterias. El mayor número de cepas y las bacterias con mayor actividad solubilizadora sobre el CBR fueron aisladas de lodo con alto contenido de residuos de carbón y las rizósferas de Typha domingensis y Cenchrus ciliaris que crecen sobre sedimentos mezclados con partículas de carbón, este resultado sugiere que la obtención y capacidad de solubilización de CBR por parte de bacterias puede estar relacionada con el microhábitat donde se desarrollan las poblaciones.

  1. Actividad Alelopática de las Arvenses Asociadas al Cultivo de Arroz (Oryza sativa L. en el Tolima-Colombia Allelophatic Activity of Arvenses Associated with the Cultivation of Rice (Oryza sativa l. in Tolima-Colombia

    Directory of Open Access Journals (Sweden)

    Elizabeth Murillo

    2006-01-01

    Full Text Available Se recolectaron e identificaron especies de arvense de la familia Asteraceae asociadas al cultivo de arroz (Oryza sativa L. en el Tolima-Colombia, y se caracterizaron morfológica, bromatológica y farmacognósticamente. Las fracciones orgánicas de la arvense con mayor contenido de sesquiterpenlactonas se evaluó por su actividad alelopática sobre la germinación y elongación de la radícula de semillas de O. sativa, colocadas en papel filtro a concentraciones de 200, 400 y 600 ppm e incubadas durante 120 horas. El cultivo de la gramínea se encontró asociado a 12 especies invasoras que presentaron gran variabilidad en sus características morfológicas y en los índices farmacognósticos. Las fracciones clorofórmicas mostraron diferencias significativas con el extracto etanólico crudo por el efecto sobre la división celular y el crecimiento radicular de semillas de O. sativa, actividad que parece estar asociada al contenido de sesquiterpenlactonas.Asteraceae weed species associated with rice (Oryza sativa L. in the state of Tolima-Colombia were gathered, identified and morphologic, pharmacognostic and bromatologically characterized. Allelopathic activity for those organic fractions of weed with high content of sesquiterpene lactone was evaluated on the germination and radicle length of O. sativa seeds in filter paper. Both crude extract and chromatographic fractions were incubated for 120 hours at concentrations of 200, 400 and 600 ppm. Cultivation of the grainswas associated to 12 weed species which presented great variability in its morphologic characteristics and farmacognostic index. Chloroformic fractions gave significant differences with the ethanolic extract due to the effect on the cellular division and the radicle elongation of the O. sativa seeds, activity that seems to be associated to the content of sesquiterpene lactone.

  2. Metodología para la Estimación de Incertidumbres Asociadas a Concentraciones de Sólidos Suspendidos Totales Mediante Métodos de Generación Aleatoria

    Directory of Open Access Journals (Sweden)

    Andrés E. Torres-Abello

    2011-06-01

    Full Text Available Este trabajo consistió en definir una metodología para estimar las incertidumbres asociadas a concentraciones de Sólidos Suspendidos Totales (SST ligados a la fase de análisis de laboratorio, contemplando no solamente la precisión de los instrumentos de laboratorio sino también el submuestreo y la manipulación de muestras y aparatos de laboratorio. La metodología propuesta tiene en cuenta el cálculo de la incertidumbre de réplicas por medio de métodos analíticos, la comparación entre los resultados de réplicas por medio de pruebas t y el cálculo de la incertidumbre compuesta por medio del método de Monte Carlo. A manera de ejemplo, la metodología desarrollada se aplica a datos de concentración de SST obtenidos en laboratorio. Dichos datos corresponden a muestras reales con bajas, medianas y elevadas concentraciones de SST y con diferencias en las variabilidades submuestrales. Posteriormente se realizan comparaciones entre las incertidumbres obtenidas al aplicar el método propuesto y aquellas obtenidas teniendo en cuenta únicamente la precisión de los aparatos de medición utilizados en laboratorio. De estas comparaciones se pudo observar que se pueden presentar diferencias importantes tanto en los re-sultados de las incertidumbres asociadas a los resultados de concentraciones como a los valores de concentración asociados a las muestras.

  3. Estructura espacial y estacional de la comunidad de hongos asociada al abrigo de hojas muertas de Espeletia grandiflora H & B en el páramo El Granizo, Monserrate-Cundinamarca, Colombia

    Directory of Open Access Journals (Sweden)

    Sabogal Rodríguez Sandra Patricia

    2002-11-01

    Full Text Available RESUMENSe caracterizó la comunidad de hongos asociada a la necromasa de Espeletia grandiflora, segúnlas siguientes variables: Grado de descomposición de la necromasa, segmentos foliares,tamaño de la planta y época climática. El muestreo se realizó durante los meses marzo - abril(seca-húmeda, agosto (seca y octubre (húmeda del año 2001. Las muestras de roseta y denecromasa a diferentes alturas con respecto al suelo (distribución vertical, fueron subdivididasen secciones foliares (distribución horizontal, procesadas según la técnica de aislamiento demicelio activo en medios de cultivo PDA y luego determinadas hasta especie. La clase-forma:Deuteromycete presentó cuatro familias, Moniliaceae, Dematiaceae, Melanconiaceae yActa Sphaeropsidaceae, donde la familia Moniliaceae exhibió la mayor riqueza de especies (4,seguida por la Dematiaceae (3; de igual forma la clase Ascomicete con cuatro familias,Sordariaceae, Chaetomiaceae, Lasiosphaerinaceae y Nectriaceae, siendo Sordariaceae la másrepresentativa en especies (2. Las clases Oomycetes y Zigomycetes presentaron una familia,Pytiaceae y Mortierelaceae respectivamente; la familia Pytiaceae estuvo representada por tresespecies. Es de anotar que, la clase-forma Deuteromycetes presenta la mayor riqueza enfamilias, especies y la mayor abundancia de individuos, sin embargo, los individuos con lasmayores frecuencias y una amplia distribución corresponden a las clases Ascomycetes yOomycete. Las especies de hongos siguieron un patrón de distribución fundamentado en laheterogeneidad espacial como temporal de los hábitats en estudio. -Pythium vexansy Sordariafimicolarepresentaron el 33% de la abundancia total de las especies de hongos asociadas a lanecromasa de Espeletia grandiflora.

  4. Estructura espacial y estacional de la comunidad de hongos asociada al abrigo de hojas muertas de Espeletia grandiflora H & B en el páramo El Granizo, Monserrate - Cundinamarca, Colombia

    Directory of Open Access Journals (Sweden)

    Anacona Chicangana Amalfy

    2002-06-01

    Full Text Available Se caracterizó la comunidad de hongos asociada a la necromasa de Espeletia grandiflora, segúnlas siguientes variables: Grado de descomposición de la necromasa, segmentos foliares, tama-ño de la planta y época climática. El muestreo se realizó durante los meses marzo-abril (seca-húmeda, agosto (seca y octubre (húmeda del año 2001. Las muestras de roseta y denecromasa a diferentes alturas con respecto al suelo (distribución vertical, fueron subdivididasen secciones foliares (distribución horizontal, procesadas según la técnica de aislamiento demicelio activo en medios de cultivo PDA y luego determinadas hasta especie. La clase-forma:Deuteromycete presentó cuatro familias, Moniliaceae, Dematiaceae, Melanconiaceae ySphaeropsidaceae, donde la familia Moniliaceae exhibió la mayor riqueza de especies (4,seguida por la Dematiaceae (3; de igual forma la clase Ascomicete con cuatro familias,Sordariaceae, Chaetomiaceae, Lasiosphaerinaceae y Nectriaceae, siendo Sordariaceae la másrepresentativa en especies (2. Las clases Oomycetes y Zigomycetes presentaron una familia,Pytiaceae y Mortierelaceae respectivamente; la familia Pytiaceae estuvo representada por tresespecies. Es de anotar que, la clase-forma Deuteromycetes presenta la mayor riqueza en fami-lias, especies y la mayor abundancia de individuos, sin embargo, los individuos con las mayoresfrecuencias y una amplia distribución correspondes a las clases Ascomycetes y Oomycete.Las especies de hongos siguieron un patrón de distribución fundamentado en la heteroge-neidad espacial como temporal de los hábitats en estudio. Pythium vexansy Sordaria fimicolarepresentaron 33% de la abundancia total de las especies de hongos asociadas a la necromasade Espeletia grandiflora.

  5. Micorrizas arbusculares asociadas a Júcaro de ciénaga ( Bucida palustris y Soplillo ( Lysiloma latisiliquum en la Reserva de la Biosfera Ciénaga de Zapata, Cuba.

    Directory of Open Access Journals (Sweden)

    Raquel M. Rodríguez Rodríguez

    2014-01-01

    Full Text Available Se evaluó y caracterizó el e status micorrízico arbuscular de Bucida palustris (j úcaro de ciénaga y Lysiloma latisiliquum (soplillo , especies distintivas de bosque de ciénaga y bosque semidecíduo con humedad fluctuante, respectivamente, en la Reserva de la Biosfera Ciénaga de Zapata . Se determinó además, la densidad de esporas rizosféricas de hongos micorrizógenos arbusculares y se identificó la especie predominante en cada caso. Ambas especies vegetales resultaron micótrofas arbusculares con elevados porcentajes de colonización (> 9 0 % y densidad visual ( >25 %. La densidad de esporas rizosféricas asociadas a Lysiloma latisiliquum fue casi 2,5 veces mayor que en Bucida palustris y las especies predominantes fueron Funneliformis halonatus y Racocetra alborosea , respectivamente. La m orfología Tipo - Paris se identificó en Lysiloma latisiliquum y el Tipo - Arum en Bucida palustris . Se observaron además de los enrollados hifales y arbúsculos determinantes de los tipos morfológicos anteriormente descritos, esporas y vesículas intrarradicales en ambas especies. Este trabajo constituye el primer reporte de micorrizas arbusculares asociadas a especies vegetales en humedales cubanos. Estudios acerca de su funcionamiento y diversidad, así como su relación con plantas cubanas permitirá una mejor co mprensión de esta simbiosis y facilitará la utilización de micorrizas nativas en estrategias de conservación y uso sostenible de plantas y ecosistemas.

  6. Cell Size Regulation in Bacteria

    Science.gov (United States)

    Amir, Ariel

    2014-05-01

    Various bacteria such as the canonical gram negative Escherichia coli or the well-studied gram positive Bacillus subtilis divide symmetrically after they approximately double their volume. Their size at division is not constant, but is typically distributed over a narrow range. Here, we propose an analytically tractable model for cell size control, and calculate the cell size and interdivision time distributions, as well as the correlations between these variables. We suggest ways of extracting the model parameters from experimental data, and show that existing data for E. coli supports partial size control, and a particular explanation: a cell attempts to add a constant volume from the time of initiation of DNA replication to the next initiation event. This hypothesis accounts for the experimentally observed correlations between mother and daughter cells as well as the exponential dependence of size on growth rate.

  7. Single Bacteria as Turing Machines

    Science.gov (United States)

    Bos, Julia; Zang, Qiucen; Vyawahare, Saurabh; Austin, Robert

    2014-03-01

    In Allan Turing's famous 1950 paper on Computing Machinery and Intelligence, he started with the provocative statement: ``I propose to consider the question, `Can machines think?' This should begin with definitions of the meaning of the terms `machine' and `think'.'' In our own work on exploring the way that organisms respond to stress and evolve, it seems at times as if they come to remarkably fast solutions to problems, indicating some sort of very clever computational machinery. I'll discuss how it would appear that bacteria can indeed create a form of a Turing Machine, the first example of a computer, and how they might use this algorithm to do rapid evolution to solve a genomics problem.

  8. Sterol synthesis in diverse bacteria

    Directory of Open Access Journals (Sweden)

    Jeremy H Wei

    2016-06-01

    Full Text Available Sterols are essential components of eukaryotic cells whose biosynthesis and function has been studied extensively. Sterols are also recognized as the diagenetic precursors of steranes preserved in sedimentary rocks where they can function as geological proxies for eukaryotic organisms and/or aerobic metabolisms and environments. However, production of these lipids is not restricted to the eukaryotic domain as a few bacterial species also synthesize sterols. Phylogenomic studies have identified genes encoding homologs of sterol biosynthesis proteins in the genomes of several additional species, indicating that sterol production may be more widespread in the bacterial domain than previously thought. Although the occurrence of sterol synthesis genes in a genome indicates the potential for sterol production, it provides neither conclusive evidence of sterol synthesis nor information about the composition and abundance of basic and modified sterols that are actually being produced. Here, we coupled bioinformatics with lipid analyses to investigate the scope of bacterial sterol production. We identified oxidosqualene cyclase (Osc, which catalyzes the initial cyclization of oxidosqualene to the basic sterol structure, in 34 bacterial genomes from 5 phyla (Bacteroidetes, Cyanobacteria, Planctomycetes, Proteobacteria and Verrucomicrobia and in 176 metagenomes. Our data indicate that bacterial sterol synthesis likely occurs in diverse organisms and environments and also provides evidence that there are as yet uncultured groups of bacterial sterol producers. Phylogenetic analysis of bacterial and eukaryotic Osc sequences confirmed a complex evolutionary history of sterol synthesis in this domain. Finally, we characterized the lipids produced by Osc-containing bacteria and found that we could generally predict the ability to synthesize sterols. However, predicting the final modified sterol based on our current knowledge of sterol synthesis was difficult

  9. Mitochondria: a target for bacteria.

    Science.gov (United States)

    Lobet, Elodie; Letesson, Jean-Jacques; Arnould, Thierry

    2015-04-01

    Eukaryotic cells developed strategies to detect and eradicate infections. The innate immune system, which is the first line of defence against invading pathogens, relies on the recognition of molecular patterns conserved among pathogens. Pathogen associated molecular pattern binding to pattern recognition receptor triggers the activation of several signalling pathways leading to the establishment of a pro-inflammatory state required to control the infection. In addition, pathogens evolved to subvert those responses (with passive and active strategies) allowing their entry and persistence in the host cells and tissues. Indeed, several bacteria actively manipulate immune system or interfere with the cell fate for their own benefit. One can imagine that bacterial effectors can potentially manipulate every single organelle in the cell. However, the multiple functions fulfilled by mitochondria especially their involvement in the regulation of innate immune response, make mitochondria a target of choice for bacterial pathogens as they are not only a key component of the central metabolism through ATP production and synthesis of various biomolecules but they also take part to cell signalling through ROS production and control of calcium homeostasis as well as the control of cell survival/programmed cell death. Furthermore, considering that mitochondria derived from an ancestral bacterial endosymbiosis, it is not surprising that a special connection does exist between this organelle and bacteria. In this review, we will discuss different mitochondrial functions that are affected during bacterial infection as well as different strategies developed by bacterial pathogens to subvert functions related to calcium homeostasis, maintenance of redox status and mitochondrial morphology.

  10. Sterol Synthesis in Diverse Bacteria.

    Science.gov (United States)

    Wei, Jeremy H; Yin, Xinchi; Welander, Paula V

    2016-01-01

    Sterols are essential components of eukaryotic cells whose biosynthesis and function has been studied extensively. Sterols are also recognized as the diagenetic precursors of steranes preserved in sedimentary rocks where they can function as geological proxies for eukaryotic organisms and/or aerobic metabolisms and environments. However, production of these lipids is not restricted to the eukaryotic domain as a few bacterial species also synthesize sterols. Phylogenomic studies have identified genes encoding homologs of sterol biosynthesis proteins in the genomes of several additional species, indicating that sterol production may be more widespread in the bacterial domain than previously thought. Although the occurrence of sterol synthesis genes in a genome indicates the potential for sterol production, it provides neither conclusive evidence of sterol synthesis nor information about the composition and abundance of basic and modified sterols that are actually being produced. Here, we coupled bioinformatics with lipid analyses to investigate the scope of bacterial sterol production. We identified oxidosqualene cyclase (Osc), which catalyzes the initial cyclization of oxidosqualene to the basic sterol structure, in 34 bacterial genomes from five phyla (Bacteroidetes, Cyanobacteria, Planctomycetes, Proteobacteria, and Verrucomicrobia) and in 176 metagenomes. Our data indicate that bacterial sterol synthesis likely occurs in diverse organisms and environments and also provides evidence that there are as yet uncultured groups of bacterial sterol producers. Phylogenetic analysis of bacterial and eukaryotic Osc sequences confirmed a complex evolutionary history of sterol synthesis in this domain. Finally, we characterized the lipids produced by Osc-containing bacteria and found that we could generally predict the ability to synthesize sterols. However, predicting the final modified sterol based on our current knowledge of sterol synthesis was difficult. Some bacteria

  11. Sterol Synthesis in Diverse Bacteria.

    Science.gov (United States)

    Wei, Jeremy H; Yin, Xinchi; Welander, Paula V

    2016-01-01

    Sterols are essential components of eukaryotic cells whose biosynthesis and function has been studied extensively. Sterols are also recognized as the diagenetic precursors of steranes preserved in sedimentary rocks where they can function as geological proxies for eukaryotic organisms and/or aerobic metabolisms and environments. However, production of these lipids is not restricted to the eukaryotic domain as a few bacterial species also synthesize sterols. Phylogenomic studies have identified genes encoding homologs of sterol biosynthesis proteins in the genomes of several additional species, indicating that sterol production may be more widespread in the bacterial domain than previously thought. Although the occurrence of sterol synthesis genes in a genome indicates the potential for sterol production, it provides neither conclusive evidence of sterol synthesis nor information about the composition and abundance of basic and modified sterols that are actually being produced. Here, we coupled bioinformatics with lipid analyses to investigate the scope of bacterial sterol production. We identified oxidosqualene cyclase (Osc), which catalyzes the initial cyclization of oxidosqualene to the basic sterol structure, in 34 bacterial genomes from five phyla (Bacteroidetes, Cyanobacteria, Planctomycetes, Proteobacteria, and Verrucomicrobia) and in 176 metagenomes. Our data indicate that bacterial sterol synthesis likely occurs in diverse organisms and environments and also provides evidence that there are as yet uncultured groups of bacterial sterol producers. Phylogenetic analysis of bacterial and eukaryotic Osc sequences confirmed a complex evolutionary history of sterol synthesis in this domain. Finally, we characterized the lipids produced by Osc-containing bacteria and found that we could generally predict the ability to synthesize sterols. However, predicting the final modified sterol based on our current knowledge of sterol synthesis was difficult. Some bacteria

  12. Progress in Research of Bacteria Fertilizer Strengthening Resistance of Plants

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Bacteria fertilizer is used most widely among all kinds of microbial fertilizers. We summarize the research headway of bacteria fertilizer. It mainly focuses on bacteria fertilizer improving the stress resistance of plant. Then we can offer basis to research and exploit bacteria fertilizer. These bacteria include azotobacter, photosynthetic bacteria, Bacillus mucilaginosus siliceous, phosphorus bacteria, plant growth-promoting rhizobacteria(PGPR), effective microorganism(EM).

  13. Sabine Kacunko. Bacteria, Art and other Bagatelles

    DEFF Research Database (Denmark)

    Kacunko, Slavko

    This book appears on the occasion of the project INVINCIBLE – a Big Bacteria project for Colosseum, Rome (17.–19.09.2015), which is being granted UNESCO-patronage in the context of the International Year of Light and Light-Based Technologies 2015. With Sabine Kacunko’s bacteria art in mind, alleged...

  14. Rapid methods for detection of bacteria

    DEFF Research Database (Denmark)

    Corfitzen, Charlotte B.; Andersen, B.Ø.; Miller, M.;

    2006-01-01

    Traditional methods for detection of bacteria in drinking water e.g. Heterotrophic Plate Counts (HPC) or Most Probable Number (MNP) take 48-72 hours to give the result. New rapid methods for detection of bacteria are needed to protect the consumers against contaminations. Two rapid methods...

  15. Lactic Acid Bacteria in the Gut

    NARCIS (Netherlands)

    Stolaki, M.; Vos, de W.M.; Kleerebezem, M.; Zoetendal, E.G.

    2012-01-01

    From all bacterial groups, the lactic acid bacteria (LAB) are probably the group of bacteria that is most associated with human lifestyle. The term LAB mainly refers to the ability of these organisms to convert sugars to lactic acid. The LAB comprise non-sporing, aerotolerant, coccus or rod-shaped,

  16. Why do bacteria engage in homologous recombination?

    NARCIS (Netherlands)

    Vos, M.

    2009-01-01

    Microbiologists have long recognized that the uptake and incorporation of homologous DNA from outside the cell is a common feature of bacteria, with important implications for their evolution. However, the exact reasons why bacteria engage in homologous recombination remain elusive. This Opinion art

  17. Method of dispersing a hydrocarbon using bacteria

    Science.gov (United States)

    Tyndall, Richard L.

    1996-01-01

    New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

  18. Quorum sensing in gram-negative bacteria

    DEFF Research Database (Denmark)

    Wu, H.; Song, Z.J.; Høiby, N.;

    2004-01-01

    molecules. Among Gram-negative bacteria N-acyl-L-homoserine lactone (acyl-HSL)-dependent quorum sensing systems are particularly widespread. These systems are used to coordinate expression of phenotypes that are fundamental to the interaction of bacteria with each other and with their environment...

  19. Resuscitation effects of catalase on airborne bacteria.

    OpenAIRE

    Marthi, B; Shaffer, B. T.; Lighthart, B; Ganio, L

    1991-01-01

    Catalase incorporation into enumeration media caused a significant increase (greater than 63%) in the colony-forming abilities of airborne bacteria. Incubation for 30 to 60 min of airborne bacteria in collection fluid containing catalase caused a greater than 95% increase in colony-forming ability. However, catalase did not have any effects on enumeration at high relative humidities (80 to 90%).

  20. Research Advances in Bacteria-based Microrobot.

    Science.gov (United States)

    Liang, Yao-Jie; Sun, Jun-Zhong

    2016-08-01

    The concept of bacteria-based microrobot has been well recognized. It has shown great advantages and potentials for the early diagnosis and early treatment of malignant tumor and in reducing chemotherapy toxicities. In this article we review the concept,structure,and potential clinical applications of bacteria-based microrobot. PMID:27594160

  1. Chemotactic selection of pollutant degrading soil bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, T.C.

    1991-03-04

    A method is described for identifying soil microbial strains which may be bacterial degraders of pollutants. This method includes: Placing a concentration of a pollutant in a substantially closed container; placing the container in a sample of soil for a period of time ranging from one minute to several hours; retrieving the container and collecting its contents; microscopically determining the identity of the bacteria present. Different concentrations of the pollutant can be used to determine which bacteria respond to each concentration. The method can be used for characterizing a polluted site or for looking for naturally occurring biological degraders of the pollutant. Then bacteria identified as degraders of the pollutant and as chemotactically attracted to the pollutant are used to innoculate contaminated soil. To enhance the effect of the bacteria on the pollutant, nutrients are cyclicly provided to the bacteria then withheld to alternately build up the size of the bacterial colony or community and then allow it to degrade the pollutant.

  2. Bacteria dispersal by hitchhiking on zooplankton

    DEFF Research Database (Denmark)

    Grossart, Hans-Peter; Dziallas, Claudia; Leunert, Franziska;

    2010-01-01

    and nonpathogenic bacteria has shown that direct association with zooplankton has significant influences on the bacteria's physiology and ecology. We used stratified migration columns to study vertical dispersal of hitchhiking bacteria through migrating zooplankton across a density gradient that was otherwise...... impenetrable for bacteria in both upward and downward directions (conveyor-belt hypothesis). The strength of our experiments is to permit quantitative estimation of transport and release of associated bacteria: vertical migration of Daphnia magna yielded an average dispersal rate of 1.3 x 10(5) x cells x...... Daphnia(-1) x migration cycle(-1) for the lake bacterium Brevundimonas sp. Bidirectional vertical dispersal by migrating D. magna was also shown for two other bacterial species, albeit at lower rates. The prediction that diurnally migrating zooplankton acquire different attached bacterial communities from...

  3. Coryneform bacteria associated with canine otitis externa

    DEFF Research Database (Denmark)

    Aalbæk, Bent; Bemis, David A.; Schjærff, Mette;

    2010-01-01

    This study aims to investigate the occurrence of coryneform bacteria in canine otitis externa. A combined case series and case-control study was carried out to improve the current knowledge on frequency and clinical significance of coryneform bacteria in samples from canine otitis externa. A total...... of 16 cases of otitis externa with involvement of coryneform bacteria were recorded at two referral veterinary hospitals in Denmark and the US, respectively. Coryneform bacteria were identified by partial 16S rRNA gene sequencing. Corynebacterium auriscanis was the most common coryneform species (10...... cases). Small colony variants of this species were also observed. Other coryneform isolates were identified as Corynebacterium amycolatum (3 cases), Corynebacterium freneyi (2 cases) and an Arcanobacterium-like species (1 case). The coryneform bacteria were in all cases isolated together with other...

  4. HYDROCARBON-DEGRADING BACTERIA AND SURFACTANT ACTIVITY

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, R; Topher Berry, T; Grazyna A. Plaza, G; jacek Wypych, j

    2006-08-15

    Fate of benzene ethylbenzene toluene xylenes (BTEX) compounds through biodegradation was investigated using two different bacteria, Ralstonia picketti (BP-20) and Alcaligenes piechaudii (CZOR L-1B). These bacteria were isolated from extremely polluted petroleum hydrocarbon contaminated soils. PCR and Fatty Acid Methyl Ester (FAME) were used to identify the isolates. Biodegradation was measured using each organism individually and in combination. Both bacteria were shown to degrade each of the BTEX compounds. Alcaligenes piechaudii biodegraded BTEXs more efficiently while mixed with BP-20 and individually. Biosurfactant production was observed by culture techniques. In addition 3-hydroxy fatty acids, important in biosurfactant production, was observed by FAME analysis. In the all experiments toluene and m+p- xylenes were better growth substrates for both bacteria than the other BTEX compounds. In addition, the test results indicate that the bacteria could contribute to bioremediation of aromatic hydrocarbons (BTEX) pollution increase biodegradation through the action by biosurfactants.

  5. Chryseobacterium indologenes, novel mannanase-producing bacteria

    Directory of Open Access Journals (Sweden)

    Surachai Rattanasuk

    2009-10-01

    Full Text Available Mannanase is a mannan degrading enzyme which is produced by microorganisms, including bacteria. This enzyme can be used in many industrial processes as well as for improving the quality of animal feeds. The aim of the present study was toscreen and characterize the mannanase-producing bacteria. Two genera of bacteria were isolated from Thai soil samples,fermented coconut, and fertilizer. Screening was carried out on agar plates containing mannan stained with iodine solution.The bacteria were identified by partial 16S rRNA gene sequence, biochemical test and morphology, respectively. The mannanase activity was determined by zymogram and DNS method. Two strains of bacteria with mannanase activity were identified as Bacillus and Chryseobacterium. This is the first report of mannanase-producing Chryseobacterium.

  6. PRODUCCIÓN DE ANTISUEROS PARA LA DETECCIÓN DE ÁCIDO INDOLACÉTICO EN CULTIVOS DE BACTERIAS PROMOTORAS DEL CRECIMIENTO VEGETAL Antisera Production to Detect Indoleacetic Acid in Cultures of Plant-Growth Promoting Bacteria

    Directory of Open Access Journals (Sweden)

    MARCIA M ROJAS

    2012-05-01

    Full Text Available Se obtuvieron antisueros en conejo utilizando como antígeno el AIA adherido a membranas de nitrocelulosa que mostraron un elevado título y especificidad. Mediante la técnica de inmunoadsorción por manchas marcadas con oro coloidal se detectó la producción de esta auxina por cepas de los géneros Gluconacetobacter, Herbaspirillum, Azospirillum, Pseudomonas, Burkholderia y Bacillus empleando como antígenos los sobrenadantes de los cultivos. Para cuantificar la producción de AIA y corroborar los datos obtenidos se empleó la técnica colorimétrica derivada de Salkowski. Los resultados muestran que todos los géneros bacterianos estudiados tienen la capacidad de producir AIA y se demuestra la factibilidad del uso de este antisuero policlonal para la detección de este metabolito. Teniendo en cuenta las potencialidades de estas bacterias, resulta de gran importancia la utilización de antisueros y técnicas serológicas para la detección rápida y sencilla de este tipo de metabolitos en bacterias asociadas a cultivos de interés económico.Rabbit polyclonal antisera against indoleacetic acid (IAA bound to nitrocellulose membrane were obtained, which exhibited a high titer and specificity. The dot immunobinding technique with colloidal gold was used to detect auxin production by several strains belonging to Gluconacetobacter, Herbaspirillum, Azospirillum, Pseudomonas, Burkholderia and Bacillus genera, using culture supernatants as antigens. Moreover, auxin production was quantified by the Salkowski's method to corroborate the previous results. It was found that that all the studied microorganisms produce IAA and the feasibility of using these antisera to detect the metabolite was confirmed. Taking into account the potentialities of plant growth promoting bacteria as biofertilizers, the use of these antisera for a rapid and easy detection of IAA in bacteria associated with important crops is thus recommended.

  7. Comparative cytotoxicity of periodontal bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, R.H.; Hammond, B.F.

    1988-11-01

    The direct cytotoxicity of sonic extracts (SE) from nine periodontal bacteria for human gingival fibroblasts (HGF) was compared. Equivalent dosages (in terms of protein concentration) of SE were used to challenge HGF cultures. The cytotoxic potential of each SE was assessed by its ability to (1) inhibit HGF proliferation, as measured by direct cell counts; (2) inhibit 3H-thymidine incorporation in HGF cultures; or (3) cause morphological alterations of the cells in challenged cultures. The highest concentration (500 micrograms SE protein/ml) of any of the SEs used to challenge the cells was found to be markedly inhibitory to the HGFs by all three of the criteria of cytotoxicity. At the lowest dosage tested (50 micrograms SE protein/ml); only SE from Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, and Fusobacterium nucleatum caused a significant effect (greater than 90% inhibition or overt morphological abnormalities) in the HGFs as determined by any of the criteria employed. SE from Capnocytophaga sputigena, Eikenella corrodens, or Wolinella recta also inhibited cell proliferation and thymidine incorporation at this dosage; however, the degree of inhibition (5-50%) was consistently, clearly less than that of the first group of three organisms named above. The SE of the three other organisms tested (Actinomyces odontolyticus, Bacteroides intermedius, and Streptococcus sanguis) had little or no effect (0-10% inhibition) at this concentration. The data suggest that the outcome of the interaction between bacterial components and normal resident cells of the periodontium is, at least in part, a function of the bacterial species.

  8. Antibiotic resistance in probiotic bacteria

    Directory of Open Access Journals (Sweden)

    Miguel eGueimonde

    2013-07-01

    Full Text Available Probiotics are live microorganisms which when administered in adequate amounts confer a health benefit on the host. The main probiotic bacteria are strains belonging to the genera Lactobacillus and Bifidobacterium, although other representatives, such as Bacillus or Escherichia coli strains, have also been used. Lactobacillus and Bifidobacterium are two common inhabitants of the human intestinal microbiota. Also, some species are used in food fermentation processes as starters, or as adjunct cultures in the food industry. With some exceptions, antibiotic resistance in these beneficial microbes does not constitute a safety concern in itself, when mutations or intrinsic resistance mechanisms are responsible for the resistance phenotype. In fact, some probiotic strains with intrinsic antibiotic resistance could be useful for restoring the gut microbiota after antibiotic treatment. However, specific antibiotic resistance determinants carried on mobile genetic elements, such as tetracycline resistance genes, are often detected in the typical probiotic genera, and constitute a reservoir of resistance for potential food or gut pathogens, thus representing a serious safety issue.

  9. Mecanismos moleculares de resistencia antibiótica en Escherichia coli asociadas a diarrea Molecular mechanisms of antibiotic resistance in Escherichia coli- associated diarrhea

    Directory of Open Access Journals (Sweden)

    Susan Mosquito

    2011-12-01

    Full Text Available La resistencia antibiótica es un problema emergente a nivel mundial presente en diversas bacterias, en especial en la Escherichia coli, que tiene altos porcentajes de resistencia hacia ampicilina, trimetoprim-sulfametoxazol, tetraciclina, cloramfenicol y ácido nalidíxico, lo que supone grandes complicaciones en el tratamiento antibiótico cuando este es requerido. Este aumento de resistencia antibiótica se debe a la adquisición de diferentes mecanismos moleculares de resistencia mediante mutaciones puntuales a nivel cromosómico o transferencia horizontal de material genético entre especies relacionadas o diferentes, facilitada por algunos elementos genéticos tales como los integrones. Esta revisión discute los efectos de los mecanismos moleculares de resistencia más comunes en E.coli: inactivación enzimática, alteraciones en el sitio blanco y alteraciones de la permeabilidad. El conocer los mecanismos de resistencia implicados, como lo recomienda la Organización Mundial de la Salud, permitirá optimizar la vigilancia de resistencia y las políticas de control y uso de antibióticos a nivel nacional.Antibiotic resistance is an emerging problem worldwide present in many bacteria, specially in Escherichia coli, which has high percentages of resistance to ampicilline, thrimethoprim-sulfamethoxazole, tetracycline, chloramphenicol and nalidixic acid, which implies important complications in antibiotic treatment when required. The increasing antibiotic resistance is due to the acquisition of different molecular mechanisms of resistance through point chromosomal mutations and /or horizontal transfer of genetic material between related or different species facilitated by some genetic elements such as integrons. This review discusses the effects of the most common molecular mechanisms of antibiotic resistance in E. coli: enzymatic inactivation, changes in the target site and permeability disturbances. Getting to know the mechanisms of

  10. Potential role of bacteria packaging by protozoa in the persistence and transmission of pathogenic bacteria.

    Science.gov (United States)

    Denoncourt, Alix M; Paquet, Valérie E; Charette, Steve J

    2014-01-01

    Many pathogenic bacteria live in close association with protozoa. These unicellular eukaryotic microorganisms are ubiquitous in various environments. A number of protozoa such as amoebae and ciliates ingest pathogenic bacteria, package them usually in membrane structures, and then release them into the environment. Packaged bacteria are more resistant to various stresses and are more apt to survive than free bacteria. New evidence indicates that protozoa and not bacteria control the packaging process. It is possible that packaging is more common than suspected and may play a major role in the persistence and transmission of pathogenic bacteria. To confirm the role of packaging in the propagation of infections, it is vital that the molecular mechanisms governing the packaging of bacteria by protozoa be identified as well as elements related to the ecology of this process in order to determine whether packaging acts as a Trojan Horse.

  11. Potential role of bacteria packaging by protozoa in the persistence and transmission of pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Alix M Denoncourt

    2014-05-01

    Full Text Available Many pathogenic bacteria live in close association with protozoa. These unicellular eukaryotic microorganisms are ubiquitous in various environments. A number of protozoa such as amoebae and ciliates ingest pathogenic bacteria, package them usually in membrane structures, and then release them into the environment. Packaged bacteria are more resistant to various stresses and are more apt to survive than free bacteria. New evidence indicates that protozoa and not bacteria control the packaging process. It is possible that packaging is more common than suspected and may play a major role in the persistence and transmission of pathogenic bacteria. To confirm the role of packaging in the propagation of infections, it is vital that the molecular mechanisms governing the packaging of bacteria by protozoa be identified as well as elements related to the ecology of this process in order to determine whether packaging acts as a Trojan Horse.

  12. Magnetotactic Bacteria from Extreme Environments

    Science.gov (United States)

    Bazylinski, Dennis A.; Lefère, Christopher T.

    2013-03-01

    Magnetotactic bacteria (MTB) represent a diverse collection of motile prokaryotes that biomineralize intracellular, membrane-bounded, tens-of-nanometer-sized crystals of a magnetic mineral called magnetosomes. Magnetosome minerals consist of either magnetite (Fe3O4) or greigite (Fe3S4) and cause cells to align along the Earth's geomagnetic field lines as they swim, a trait called magnetotaxis. MTB are known to mainly inhabit the oxic-anoxic interface (OAI) in water columns or sediments of aquatic habitats and it is currently thought that magnetosomes function as a means of making chemotaxis more efficient in locating and maintaining an optimal position for growth and survival at the OAI. Known cultured and uncultured MTB are phylogenetically associated with the Alpha-, Gamma- and Deltaproteobacteria classes of the phylum Proteobacteria, the Nitrospirae phylum and the candidate division OP3, part of the Planctomycetes-Verrucomicrobia-Chlamydiae (PVC) bacterial superphylum. MTB are generally thought to be ubiquitous in aquatic environments as they are cosmopolitan in distribution and have been found in every continent although for years MTB were thought to be restricted to habitats with pH values near neutral and at ambient temperature. Recently, however, moderate thermophilic and alkaliphilic MTB have been described including: an uncultured, moderately thermophilic magnetotactic bacterium present in hot springs in northern Nevada with a probable upper growth limit of about 63 °C; and several strains of obligately alkaliphilic MTB isolated in pure culture from different aquatic habitats in California, including the hypersaline, extremely alkaline Mono Lake, with an optimal growth pH of >9.0.

  13. Magnetotactic Bacteria from Extreme Environments

    Directory of Open Access Journals (Sweden)

    Christopher T. Lefèvre

    2013-03-01

    Full Text Available Magnetotactic bacteria (MTB represent a diverse collection of motile prokaryotes that biomineralize intracellular, membrane-bounded, tens-of-nanometer-sized crystals of a magnetic mineral called magnetosomes. Magnetosome minerals consist of either magnetite (Fe3O4 or greigite (Fe3S4 and cause cells to align along the Earth’s geomagnetic field lines as they swim, a trait called magnetotaxis. MTB are known to mainly inhabit the oxic–anoxic interface (OAI in water columns or sediments of aquatic habitats and it is currently thought that magnetosomes function as a means of making chemotaxis more efficient in locating and maintaining an optimal position for growth and survival at the OAI. Known cultured and uncultured MTB are phylogenetically associated with the Alpha-, Gamma- and Deltaproteobacteria classes of the phylum Proteobacteria, the Nitrospirae phylum and the candidate division OP3, part of the Planctomycetes-Verrucomicrobia-Chlamydiae (PVC bacterial superphylum. MTB are generally thought to be ubiquitous in aquatic environments as they are cosmopolitan in distribution and have been found in every continent although for years MTB were thought to be restricted to habitats with pH values near neutral and at ambient temperature. Recently, however, moderate thermophilic and alkaliphilic MTB have been described including: an uncultured, moderately thermophilic magnetotactic bacterium present in hot springs in northern Nevada with a probable upper growth limit of about 63 °C; and several strains of obligately alkaliphilic MTB isolated in pure culture from different aquatic habitats in California, including the hypersaline, extremely alkaline Mono Lake, with an optimal growth pH of >9.0.

  14. R-body-producing bacteria.

    Science.gov (United States)

    Pond, F R; Gibson, I; Lalucat, J; Quackenbush, R L

    1989-03-01

    Until 10 years ago, R bodies were known only as diagnostic features by which endosymbionts of paramecia were identified as kappa particles. They were thought to be limited to the cytoplasm of two species in the Paramecium aurelia species complex. Now, R bodies have been found in free-living bacteria and other Paramecium species. The organisms now known to form R bodies include the cytoplasmic kappa endosymbionts of P. biaurelia and P. tetraurelia, the macronuclear kappa endosymbionts of P. caudatum, Pseudomonas avenae (a free-living plant pathogen), Pseudomonas taeniospiralis (a hydrogen-oxidizing soil microorganism), Rhodospirillum centenum (a photosynthetic bacterium), and a soil bacterium, EPS-5028, which is probably a pseudomonad. R bodies themselves fall into five distinct groups, distinguished by size, the morphology of the R-body ribbons, and the unrolling behavior of wound R bodies. In recent years, the inherent difficulties in studying the organization and assembly of R bodies by the obligate endosymbiont kappa, have been alleviated by cloning and expressing genetic determinants for these R bodies (type 51) in Escherichia coli. Type 51 R-body synthesis requires three low-molecular-mass polypeptides. One of these is modified posttranslationally, giving rise to 12 polypeptide species, which are the major structural subunits of the R body. R bodies are encoded in kappa species by extrachromosomal elements. Type 51 R bodies, produced in Caedibacter taeniospiralis, are encoded by a plasmid, whereas bacteriophage genomes probably control R-body synthesis in other kappa species. However, there is no evidence that either bacteriophages or plasmids are present in P. avenae or P. taeniospiralis. No sequence homology was detected between type 51 R-body-encoding DNA and DNA from any R-body-producing species, except C. varicaedens 1038. The evolutionary relatedness of different types of R bodies remains unknown. PMID:2651865

  15. Folate Production by Probiotic Bacteria

    Directory of Open Access Journals (Sweden)

    Stefano Raimondi

    2011-01-01

    Full Text Available Probiotic bacteria, mostly belonging to the genera Lactobacillus and Bifidobacterium, confer a number of health benefits to the host, including vitamin production. With the aim to produce folate-enriched fermented products and/or develop probiotic supplements that accomplish folate biosynthesis in vivo within the colon, bifidobacteria and lactobacilli have been extensively studied for their capability to produce this vitamin. On the basis of physiological studies and genome analysis, wild-type lactobacilli cannot synthesize folate, generally require it for growth, and provide a negative contribution to folate levels in fermented dairy products. Lactobacillus plantarum constitutes an exception among lactobacilli, since it is capable of folate production in presence of para-aminobenzoic acid (pABA and deserves to be used in animal trials to validate its ability to produce the vitamin in vivo. On the other hand, several folate-producing strains have been selected within the genus Bifidobacterium, with a great variability in the extent of vitamin released in the medium. Most of them belong to the species B. adolescentis and B. pseudocatenulatum, but few folate producing strains are found in the other species as well. Rats fed a probiotic formulation of folate-producing bifidobacteria exhibited increased plasma folate level, confirming that the vitamin is produced in vivo and absorbed. In a human trial, the same supplement raised folate concentration in feces. The use of folate-producing probiotic strains can be regarded as a new perspective in the specific use of probiotics. They could more efficiently confer protection against inflammation and cancer, both exerting the beneficial effects of probiotics and preventing the folate deficiency that is associated with premalignant changes in the colonic epithelia.

  16. Folate production by probiotic bacteria.

    Science.gov (United States)

    Rossi, Maddalena; Amaretti, Alberto; Raimondi, Stefano

    2011-01-01

    Probiotic bacteria, mostly belonging to the genera Lactobacillus and Bifidobacterium, confer a number of health benefits to the host, including vitamin production. With the aim to produce folate-enriched fermented products and/or develop probiotic supplements that accomplish folate biosynthesis in vivo within the colon, bifidobacteria and lactobacilli have been extensively studied for their capability to produce this vitamin. On the basis of physiological studies and genome analysis, wild-type lactobacilli cannot synthesize folate, generally require it for growth, and provide a negative contribution to folate levels in fermented dairy products. Lactobacillus plantarum constitutes an exception among lactobacilli, since it is capable of folate production in presence of para-aminobenzoic acid (pABA) and deserves to be used in animal trials to validate its ability to produce the vitamin in vivo. On the other hand, several folate-producing strains have been selected within the genus Bifidobacterium, with a great variability in the extent of vitamin released in the medium. Most of them belong to the species B. adolescentis and B. pseudocatenulatum, but few folate producing strains are found in the other species as well. Rats fed a probiotic formulation of folate-producing bifidobacteria exhibited increased plasma folate level, confirming that the vitamin is produced in vivo and absorbed. In a human trial, the same supplement raised folate concentration in feces. The use of folate-producing probiotic strains can be regarded as a new perspective in the specific use of probiotics. They could more efficiently confer protection against inflammation and cancer, both exerting the beneficial effects of probiotics and preventing the folate deficiency that is associated with premalignant changes in the colonic epithelia. PMID:22254078

  17. The Microworld of Marine-Bacteria

    DEFF Research Database (Denmark)

    JØRGENSEN, BB

    1995-01-01

    Microsensor studies show that the marine environment in the size scale of bacteria is physically and chemically very different from the macroenvironment. The microbial world of the sediment-water interface is thus dominated by water viscosity and steep diffusion gradients. Because of the diverse...... metabolism types, bacteria in the mostly anoxic sea floor play an important role in the major element cycles of the ocean. The communities of giant, filamentous sulfur bacteria that live in the deep-sea hydrothermal vents or along the Pacific coast of South America are presented here as examples....

  18. Stop the Spread of Superbugs: Help Fight Drug Resistant Bacteria

    Science.gov (United States)

    ... the Spread of Superbugs Help Fight Drug-Resistant Bacteria For nearly a century, bacteria-fighting drugs known as antibiotics have helped to control and destroy many of the harmful bacteria that can make us sick. But in recent ...

  19. Birefringence Determination of Magnetic Moments of Magnetotactic Bacteria

    OpenAIRE

    Rosenblatt, Charles; de Araujo, F. Flavio Torres; Frankel, Richard B.

    1982-01-01

    A birefringence technique is used to determine the average magnetic moments of magnetotactic bacteria in culture. Differences in are noted between live and dead bacteria, as well as between normal density and high density samples of live bacteria.

  20. Mortalidade por aborto no Estado de Santa Catarina - 1996 a 2005 Mortalidad materna asociada al aborto en el Estado de Santa Catarina - 1996 a 2005 Abortion mortality in the Santa Catarina State from 1996 to 2005

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes de Souza

    2008-12-01

    Full Text Available A mortalidade materna associada ao aborto revela as condições sociais da mulher. Este estudo, exploratório-descritivo, tem o objetivo de identificar o perfil das mulheres que tiveram morte associada ao aborto no Estado de Santa Catarina, no período de 1996 a 2005. As fontes para a coleta dos dados foram: o Sistema de Informações sobre Mortalidade e o Sistema de Informações sobre os Nascidos Vivos, do Ministério da Saúde do Brasil. Foram encontradas 31 mortes maternas associadas ao aborto; destas, 51,61% ocorreram em mulheres casadas; 38,71% das mulheres tinham de 1 a 8 anos de escolaridade, e para 48,39% o grau de instrução foi registrado como ignorado. Os dois valores mais elevados da razão de mortalidade materna foram encontrados na Região Oeste, 5,148, e na Região Norte, 4,761.La mortalidad materna asociada al aborto revela las condiciones sociales de la mujer. El objetivo de este estudio exploratorio descriptivo es identificar el perfil de la mujer con muerte asociada al aborto en el estado de Santa Catarina, en el período de 1996 hasta 2005. Las fuentes para la colecta de los datos fueron el Sistema de Informaciones sobre Mortalidad y el Sistema de Informaciones sobre los Nacidos Vivos, del Ministerio de la Salud de Brasil. Fueron analizadas 31 muertes maternas asociadas al aborto, de estas 51,61% ocurrieron en mujeres casadas; 38,71% tenían de 1 a 8 años de escolaridad, y 48,39% grado de instrucción ignorado. En la región Oeste del estado fue observada la razón de mortalidad materna de 5,148, seguida de la Región Norte con 4,761.The Maternal Mortality associated with abortion reveals woman social conditions in life. The goal of this exploratory and descriptive study is to identify the profile of women who have had death associated with abortion in the Santa Catarina State during the period of 1996 to 2005. The source of data collection was the Information System on Mortality and the Information System of Live Newborns

  1. Francisella philomiragia, bacteria asociada con altas mortalidades en salmones del Atlántico (Salmo salar cultivados en balsas-jaulas en el lago Llanquihue Francisella philomiragia, a bacteria associated with high mortalities in Atlantic salmon (Salmo salar cage-farmed in Llanquihue lake

    Directory of Open Access Journals (Sweden)

    H Bohle

    2009-01-01

    Full Text Available Francisella philomiragia fue aislada de salmón del Atlántico cultivado en balsas-jaulas en el lago Llanquihue con brotes de una enfermedad granulomatosa con altas tasas de morbilidad y mortalidad acumuladas entre 5% a 20%. Los aislados bacterianos tienen 100% similitud con F. philomiragia ssp noatunensis o F. piscicida aislado de bacalao en Noruega, 99% de similitud con Francisella sp. detectado en tilapia en Asia y Centroamérica y 99% de similitud con la especie tipo F. philomiragia por análisis filogenético del gen 16s rDNA.Francisella philomiragia was isolated from Atlantic salmon cage-farmed in the Llanquihue lake with outbreaks of a granulomatous disease, with high rates of morbidity and an accumulated mortalities between 5% to 20%. The isolates had 100% similarity with F. philomiragia ssp noatunensis or F. piscicida isolated in Atlantic cod, 99% similarity with Francisella sp. detected in tilapia from Asia and Central America and 99% of similarity with the reference strain F. philomiragia through 16s rDNA phylogenetic analysis.

  2. Francisella philomiragia, bacteria asociada con altas mortalidades en salmones del Atlántico (Salmo salar) cultivados en balsas-jaulas en el lago Llanquihue Francisella philomiragia, a bacteria associated with high mortalities in Atlantic salmon (Salmo salar) cage-farmed in Llanquihue lake

    OpenAIRE

    H Bohle; Tapia, E.; A Martínez; M Rozas; Figueroa, A.; Bustos, P.

    2009-01-01

    Francisella philomiragia fue aislada de salmón del Atlántico cultivado en balsas-jaulas en el lago Llanquihue con brotes de una enfermedad granulomatosa con altas tasas de morbilidad y mortalidad acumuladas entre 5% a 20%. Los aislados bacterianos tienen 100% similitud con F. philomiragia ssp noatunensis o F. piscicida aislado de bacalao en Noruega, 99% de similitud con Francisella sp. detectado en tilapia en Asia y Centroamérica y 99% de similitud con la especie tipo F. philomiragia por anál...

  3. Evaluación del potencial biofertilizante de bacterias diazótrofas aisladas de suelos con cultivo de cacao (Theobroma cacao L.

    Directory of Open Access Journals (Sweden)

    Adriana Zulay Argüello-Navarro

    2014-09-01

    Full Text Available La adaptabilidad del cacao (Theobroma cacao L. en condiciones adversas permite sugerir que la microbiota asociada con la rizosfera desempeña una función importante para la nutrición y el desarrollo de la planta. En el trabajo se evaluó el potencial biofertilizante de bacterias fijadoras de nitrógeno (diazótrofas aisladas de suelos cacaoteros por la técnica de diluciones seriadas. Las bacterias se aislaron en medios semiselectivos (NFb, JMV, LGI, JNFb. Los aislados puros se caracterizaron morfológica y bioquímicamente y complementariamente se evaluó la capacidad de fijación biológica de nitrógeno (FBN por el método de Micro-Kjeldahl. Los aislados con mejor capacidad de fijación de nitrógeno fueron seleccionados para evaluar su potencial promotor de crecimiento durante 120 días en plantas de cacao clon CCN 51 establecidas a partir de semillas. El análisis de datos mostró que las plantas de cacao respondieron efectivamente a los tratamientos con bacterias donde las variables de crecimiento y N (% foliar incrementaron significativamente, en comparación con el testigo. Se destacó el aporte de los aislados DKA2J24, DKB3J73 presuntamente del género Burkholderia sp. y DKA1L3 semejante al género Gluconacetobacter sp., todos con un gran potencial como biofertilizantes en la prueba de bioensayo.

  4. Neumatosis intestinal asociada a neumatosis portal intrahepática por oclusión intestinal: presentación de un caso Pneumatosis intestinalis and intrahepatic portal venous gas associated with small bowel occlusion: case report

    Directory of Open Access Journals (Sweden)

    Lucas E Granero

    2010-04-01

    Full Text Available La neumatosis intestinal es una entidad muy infrecuente asociada a varias patologías, como el infarto intestino-mesentérico, la enterocolitis necrotizante y la enfermedad pulmonar obstructiva crónica. Se caracteriza por la presencia de gas en la subserosa o submucosa a través del tracto gastrointestinal. Presentamos el caso de un paciente de sexo masculino de 63 años de edad que consultó por dolor en abdomen superior, vómitos y fiebre elevada (39º nueve días después de una gastrectomía total por cáncer. La radiografía directa de abdomen constató distensión intestinal y la tomografía computada (TC demostró distensión intestinal, edema mesentérico, neumatosis intestinal a través del intestino delgado y neumatosis portal, preferentemente en el lóbulo hepático izquierdo. Se realizó una laparotomía de urgencia que reveló únicamente distensión intestinal por adherencias, sin evidenciar necrosis intestinal. El paciente evolucionó desfavorablemente, falleciendo posteriormente. Reportamos un nuevo caso y revisamos la literatura de la neumatosis intestinal asociada con neumatosis portal.The pneumatosis intestinalis is a very infrequent condition associated with a number of diseases, such as mesenteric infarction, necrotizing enterocolitis, and obstructive pulmonary disease characterized by the presence of subserosal or submucosal gas cyst throughout the gastrointestinal tract. A 63- year- old man complained of upper abdominal pain, vomiting and high fever (39º C on the nine day after total gastrectomy for cancer. Abdominal X-ray revealed intestinal distension. The abdominal Computed Tomography (CT showed intestinal dilatation, mesenteric oedema, diffuse pneumatosis throughout the small intestine and gas in the portal venous system predominantly in the left hepatic lobe. It was performed emergency activity that revealed intestinal distension secondary to adhesion without intestinal necrosis. The patient had a downhill course

  5. Observaciones sobre la patogénesis de la anorexia asociada a cáncer y su regulación por el sistema nervioso central Neural pathophysiology of cancer anorexia

    Directory of Open Access Journals (Sweden)

    K. Sánchez-Lara

    2011-08-01

    Full Text Available Introducción: Se estima que dos terceras partes de los pacientes con cáncer sufren de anorexia o pérdida significativa de apetito, lo que conduce a la disminución acentuada de peso y desnutrición, con repercusiones significativas en la calidad de vida y morbimortalidad de los afectados. Aún se desconocen los mecanismos precisos que originan la pérdida de apetito; diversas hipótesis proponen que la patogénesis es multifactorial, destacándose las características biológicas del tumor, del huésped y las relacionadas al tratamiento. Existen nuevas teorías que señalan diversas substancias con efectos antimetabólicos en el sistema nervioso central y que parecen asociarse con resistencia a señales periféricas que informan al hipotálamo sobre el estado de consumo y gasto energético corporal. El objetivo de la revisión es describir conceptos actuales sobre la patogénesis de la anorexia asociada al cáncer, con particular interés en alteraciones del sistema nervioso central. Conclusiones: Es necesario continuar investigando los mecanismos participantes a nivel neural involucrados en la regulación alimentaria, con la finalidad de implementar mejores medidas de alimentación y tratamiento de los pacientes oncológicos con perdida de apetito, mejorar su estado nutricio, su calidad de vida y sobre todo, reducir la morbimortalidad asociada a desnutrición.Introduction: Approximately two thirds of cancer patients at advanced stages of the disease suffer from anorexia. Defined as the loss of the desire to eat, anorexia lower the energy intake which further exacerbates a progressive deterioration of the patient nutritional status. Malnutrition has a large impact on morbidity and mortality affecting the quality of life. Cancer anorexia etiology is multifactorial including complex interactions among the tumor, host metabolism and antineoplastic treatment. New related theories include peripheral and brain mechanisms affecting hypothalamic

  6. Emotional dysfunction associated with diabetes in Mexican adolescents and young adults with type-1 diabetes Disfunción emocional asociada a diabetes en adolescentes y adultos jóvenes mexicanos con diabetes tipo 1

    Directory of Open Access Journals (Sweden)

    Israel Lerman-Garber

    2003-01-01

    Full Text Available OBJECTIVE: To assess the emotional dysfunction associated with diabetes in Mexican young individuals with type-1 diabetes. MATERIAL AND METHODS: A cross-sectional survey was conducted to perform a complete clinical and psychosocial evaluation of 93 consecutive type-1 diabetes patients, aged 14 to 30 years. RESULTS: Adolescents had higher scores of emotional dysfunction related to diabetes and a diminished knowledge in diabetes-related areas. A multivariate logistic regression model showed that an inadequate emotional response to diabetes (high problem areas in diabetes or PAID scores was mainly associated with a poor glycemic control (OR=2.9, 95% CI 0.9-9.7, p=0.09. Apprehension about the future and the possibility of serious complications had the highest mean PAID score in all age groups. CONCLUSIONS: New strategies should be developed to improve the routine care and support of young individuals with type-1 diabetes.OBJETIVO: Investigar la disfunción emocional asociada con la diabetes en jóvenes mexicanos con diabetes tipo 1. MATERIAL Y MÉTODOS: Estudio transversal que incluyó la evaluación clínica y psicosocial de 93 pacientes con diabetes tipo 1 con edades comprendidas entre los 14 y los 30 años. RESULTADOS: Los adolescentes como grupo presentaron mayor disfunción emocional asociada con la diabetes y menores conocimientos en las diferentes áreas de diabetes. En un análisis de regresión logística multivariado, una respuesta emocional inadecuada (calificación alta de áreas problema en diabetes o PAID, por sus siglas en inglés, se asoció principalmente con un mal control glucémico (OR=2.9; 95% CI 0.9-9.7 p=0.09. La preocupación acerca del futuro y la posibilidad de desarrollar complicaciones se asoció con las calificaciones más altas de PAID en todos los grupos de edad. CONCLUSIONES: Es una imperiosa necesidad desarrollar nuevas estrategias que permitan mejorar el cuidado y brindar más apoyo a los jóvenes con diabetes tipo

  7. Abundance, viability and culturability of Antarctic bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.; DeSouza, M.J.B.D.; Nair, S.; Chandramohan, D.

    The viability of total number of bacteria decide the mineralisation rate in any ecosystem and ultimately the fertility of the region. This study aims at establishing the extent of viability in the standing stock of the Antarctic bacterial population...

  8. Distribution of phytopathogenic bacteria in infested seeds

    Science.gov (United States)

    Populations of phytopathogenic bacteria representing five host-pathogen combinations were assessed to determine if there was a mathematical relationship common across seedborne bacterial diseases. Bacterial populations were estimated from naturally-infested seeds of cowpea (Vigna unguiculata), peppe...

  9. Protection of probiotic bacteria in synbiotic matrices

    Science.gov (United States)

    Probiotics, like Lactobacillus acidophilus, Lactobacillus reuteri, Bifidobacterium breve, Bifidobacterium longum, when encapsulated with prebiotic fibers such as fructo-oligosaccharides (FOS), inulin (I) and pectic-oligosaccharides (POS), formed a synbiotic matrix system that protected the bacteria ...

  10. Quorum sensing in Gram-negative bacteria

    Institute of Scientific and Technical Information of China (English)

    WU Hong; SONG Zhijun; Niels HФIBY; Michael GIVSKOV

    2004-01-01

    Bacteria can communicate with each other by means of signal molecules to coordinate the behavior of the entire community,and the mechanism is referred to as quorum sensing (QS).Signal systems enable bacteria to sense the size of their densities by monitoring the concentration of the signal molecules.Among Gram-negative bacteria N-acyl-L-homoserine lactone (acyl-HSL)-dependent quorum sensing systems are particularly widespread.These systems are used to coordinate expression of phenotypes that are fundamental to the interaction of bacteria with each other and with their environment and particularly higher organisms,covering a variety of functions ranging from pathogenic to symbiotic interactions.The detailed knowledge of these bacterial communication systems has opened completely new perspectives for controlling undesired microbial activities.

  11. Ecology: Electrical Cable Bacteria Save Marine Life.

    Science.gov (United States)

    Nielsen, Lars Peter

    2016-01-11

    Animals at the bottom of the sea survive oxygen depletion surprisingly often, and a new study identifies cable bacteria in the sediment as the saviors. The bacterial electrical activity creates an iron 'carpet', trapping toxic hydrogen sulfide.

  12. Comparative genomics of the lactic acid bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Makarova, K.; Slesarev, A.; Wolf, Y.; Sorokin, A.; Mirkin, B.; Koonin, E.; Pavlov, A.; Pavlova, N.; Karamychev, V.; Polouchine, N.; Shakhova, V.; Grigoriev, I.; Lou, Y.; Rokhsar, D.; Lucas, S.; Huang, K.; Goodstein, D. M.; Hawkins, T.; Plengvidhya, V.; Welker, D.; Hughes, J.; Goh, Y.; Benson, A.; Baldwin, K.; Lee, J. -H.; Diaz-Muniz, I.; Dosti, B.; Smeianov, V; Wechter, W.; Barabote, R.; Lorca, G.; Altermann, E.; Barrangou, R.; Ganesan, B.; Xie, Y.; Rawsthorne, H.; Tamir, D.; Parker, C.; Breidt, F.; Broadbent, J.; Hutkins, R.; O' Sullivan, D.; Steele, J.; Unlu, G.; Saier, M.; Klaenhammer, T.; Richardson, P.; Kozyavkin, S.; Weimer, B.; Mills, D.

    2006-06-01

    Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.

  13. Comparative Genomics of Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Ussery, David; Davenport, C; Tümmler, B

    2010-01-01

    Eleven completely sequenced Chlorobi genomes were compared in oligonucleotide usage, gene contents, and synteny. The green sulfur bacteria (GSB) are equipped with a core genome that sustains their anoxygenic phototrophic lifestyle by photosynthesis, sulfur oxidation, and CO(2) fixation. Whole...

  14. Microgravity effects on pathogenicity of bacteria

    OpenAIRE

    Wang, Ya-Juan; Liu, Chang-Ting

    2013-01-01

    Microgravity is one of the important environmental conditions during spaceflight. A series of studies have shown that many kinds of bacteria could be detected in space station and space shuttle. Space environment or simulated microgravity may throw a certain influence on those opportunistic pathogens and lead to some changes on their virulence, biofilm formation and drug tolerance. The mechanism of bacteria response to space environment or simulated microgravity has not been defined. However,...

  15. Keratinolytic activity of cutaneous and oral bacteria.

    OpenAIRE

    Mikx, F H; De Jong, M H

    1987-01-01

    A test was developed to measure the keratinolytic activity of cutaneous and oral bacteria. Keratin, labeled with fluorescein isothiocyanate, was used in a phosphate buffer (pH 7.2) with 1 mM dithiothreitol. The degradation of keratin was estimated by measuring the fluorescence of the degradation products in the supernatant of the reaction mixtures in a luminescence spectrometer. Several oral and cutaneous bacteria were investigated: Bacteroides gingivalis, Bacteroides intermedius, Treponema d...

  16. Interactions between ectomycorrhizal associations and bacteria

    OpenAIRE

    Marupakula, Srisailam

    2016-01-01

    Boreal forest podzol soils have vertically stratified horizons with different physico-chemical characteristics and high microbial diversity. Ectomycorrhizal fungi play key roles in accessing nutrients from both organic and mineral substrates. The role of associated bacteria in these processes is still poorly understood. The aim of the studies described in this thesis was to improve understanding of the distribution, diversity and community structure of fungi and bacteria on roots and in soil ...

  17. How Bacteria Turn Fiber into Food

    OpenAIRE

    Martens, Eric C.; Lowe, Elisabeth C.; Chiang, Herbert; Nicholas A Pudlo; Wu, Meng; McNulty, Nathan P.; Abbott, D Wade; Henrissat, Bernard; Gilbert, Harry J.; Bolam, David N.; Jeffrey I Gordon

    2011-01-01

    Symbiotic bacteria inhabiting the human gut have evolved under intense pressure to utilize complex carbohydrates, primarily plant cell wall glycans in our diets. These polysaccharides are not digested by human enzymes, but are processed to absorbable short chain fatty acids by gut bacteria. The Bacteroidetes, one of two dominant bacterial phyla in the adult gut, possess broad glycan-degrading abilities. These species use a series of membrane protein complexes, termed Sus-like systems, for cat...

  18. Bacteria in goat meat: Biological danger

    OpenAIRE

    Ivanović S.; Pavlović I.; Žujović M.; Tomić Z.; Memiši N.

    2011-01-01

    In the world, especially in China, India, Pаkistаn and Nigeria goat meat represents an important foodstuff in nutrition of people. Goat meat is being increasingly consumed in Serbia owing to its distinctive taste and desirable chemical composition. As many other types of meat, goat meat can be the source of pathogenic bacteria. Bacteria can find their way into meat of healthy goats or goats with no clinical symptoms premortally (infection) or postmortally (...

  19. Study of Lactobacillus as Probiotic Bacteria

    OpenAIRE

    J. Nowroozi; Mirzaii, M; M. Norouzi

    2004-01-01

    Because of inhibitory effect, selected probiotic lactobacilli may be used as biological preservative, so, the aim of this study was to present some data on lactobacillus as probiotic bacteria. Lactic acid bacteria were isolated from sausage. Each isolate of lactobacillus species was identified by biochemical tests and comparing their sugar fermentation pattern. Antibacterial activities were done by an agar spot, well diffusion and blank disk method. Enzyme sensitivity of supernatant fluid and...

  20. Ecology: Electrical Cable Bacteria Save Marine Life

    DEFF Research Database (Denmark)

    Nielsen, Lars Peter

    2016-01-01

    Animals at the bottom of the sea survive oxygen depletion surprisingly often, and a new study identifies cable bacteria in the sediment as the saviors. The bacterial electrical activity creates an iron 'carpet', trapping toxic hydrogen sulfide.......Animals at the bottom of the sea survive oxygen depletion surprisingly often, and a new study identifies cable bacteria in the sediment as the saviors. The bacterial electrical activity creates an iron 'carpet', trapping toxic hydrogen sulfide....

  1. Manganese Oxidation by Bacteria: Biogeochemical Aspects

    Digital Repository Service at National Institute of Oceanography (India)

    Sujith, P.P.; LokaBharathi, P.A.

    and protection against oxidative stress in bacteria (Christianson 1997 and Spiro et al. 2010). It is important for general metabolism, carbohydrate metabolism and for both anabolic and catabolic functions in anaerobiosis and aerobiosis (Crowley et al. 2000... in biochemical processes in rivers must be great but require further investigations to know about their nutritional needs, metabolism and enzymatic systems. Knowing the importance of Mn 2+ oxidation by bacteria Johnson and Stokes (1966) readily stated...

  2. Molecular genetic studies on obligate anaerobic bacteria

    International Nuclear Information System (INIS)

    Molecular genetic studies on obligate anaerobic bacteria have lagged behind similar studies in aerobes. However, the current interest in biotechnology, the involvement of anaerobes in disease and the emergence of antibioticresistant strains have focused attention on the genetics of anaerobes. This article reviews molecular genetic studies in Bacteroides spp., Clostridium spp. and methanogens. Certain genetic systems in some anaerobes differ from those in aerobes and illustrate the genetic diversity among bacteria

  3. Quorum sensing mechanism in lactic acid bacteria

    Directory of Open Access Journals (Sweden)

    Hatice Yılmaz - Yıldıran

    2015-04-01

    and detection occurs as a consecution it is hard to understand their QS mechanism. In this review, connection between QS mechanism and some characteristics of lactic acid bacteria are evaluated such as concordance with its host, inhibition of pathogen development and colonization in gastrointestinal system, bacteriocin production, acid and bile resistance, adhesion to epithelium cells. Understanding QS mechanism of lactic acid bacteria will be useful to design metabiotics which is defined as novel probiotics.

  4. Study of Lactobacillus as Probiotic Bacteria

    Directory of Open Access Journals (Sweden)

    J Nowroozi

    2004-07-01

    Full Text Available Because of inhibitory effect, selected probiotic lactobacilli may be used as biological preservative, so, the aim of this study was to present some data on lactobacillus as probiotic bacteria. Lactic acid bacteria were isolated from sausage. Each isolate of lactobacillus species was identified by biochemical tests and comparing their sugar fermentation pattern. Antibacterial activities were done by an agar spot, well diffusion and blank disk method. Enzyme sensitivity of supernatant fluid and concentrated cell free culture after treatment with α-amylase, lysozyme and trypsin was determined. The isolated bacteria were Lacto. plantarum, Lacto delbruekii, Lacto. acidophilus, Lacto. brevis. The isolated bacteria had strong activity against indicator strains. The antibacterial activity was stable at 100ºC for 10 min and at 56ºC for 30 min, but activity was lost after autoclaving. The maximum production of plantaricin was obtained at 25 - 30ºC at pH 6.5. Because, lactobacilli that used to process sausage fermentation are producing antimicrobial activity with heat stability bacteriocin, so, these bacteria may be considered to be a healthy probiotic diet. Lactobacilli originally isolated from meat products are the best condidates as probiotic bacteria to improve the microbiological safety of these foods.

  5. Mimicking Seawater For Culturing Marine Bacteria

    DEFF Research Database (Denmark)

    Rygaard, Anita Mac; Sonnenschein, Eva; Gram, Lone;

    2015-01-01

    Only about 1% of marine bacteria have been brought into culture using traditional techniques. The purpose of this study was to investigate if mimicking the natural bacterial environment can increase culturability.We used marine substrates containing defined algal polymers or gellan gum as solidif......Only about 1% of marine bacteria have been brought into culture using traditional techniques. The purpose of this study was to investigate if mimicking the natural bacterial environment can increase culturability.We used marine substrates containing defined algal polymers or gellan gum...... as solidifying agents, and enumerated bacteria from seawater and algal exudates. We tested if culturability could be influenced by addition of quorum sensing signals (AHLs). All plates were incubated at 15°C. Bacterial counts (CFU/g) from algal exudates from brown algae were highest on media containing algal...... polymers. In general, bacteria isolated from algal exudates preferred more rich media than bacteria isolated from seawater. Overall, culturability ranged from 0.01 to 0.8% as compared to total cell count. Substitution of agar with gellan gum increased the culturability of seawater bacteria approximately...

  6. Competition for hydrogen by human faecal bacteria: evidence for the predominance of methane producing bacteria.

    OpenAIRE

    Strocchi, A; Furne, J K; Ellis, C J; Levitt, M D

    1991-01-01

    Studies of sludge have shown that some species of sulphate reducing bacteria outcompete methane producing bacteria for the common substrate H2. A similar competition may exist in human faeces where the methane (CH4) producing status of an individual depends on the faecal concentration of sulphate reducing bacteria. To determine if non-methanogenic faeces outcompete CH4 producing faeces for H2, aliquots of each type of faeces were incubated alone or mixed together, with or without addition of ...

  7. Selección y caracterización de rizobacterias promotoras de crecimiento vegetal (RPCV asociadas al cultivo de algodón (Gossypium hirsutum

    Directory of Open Access Journals (Sweden)

    Andrés Guzmán

    2012-04-01

    Full Text Available Normal 0 21 false false false ES-CO X-NONE X-NONE MicrosoftInternetExplorer4 Título en ingles: Selection and characterization of plant growth promoting rhizobacteria (PGPR’s associated with cotton crop (Gossypium hirsutum Resumen: Como parte de las estrategias de una agricultura sostenible, se hace necesario disminuir el uso de fertilizantes nitrogenados de síntesis, mediante la utilización de los biofertilizantes. En particular, los géneros Azotobacter y Azospirillum son utilizados como agentes promotores de crecimiento vegetal debido a su capacidad para fijar nitrógeno atmosférico y producir hormonas de tipo indólico. Por tal razón, en este estudio se aislaron bacterias diazotróficas de los géneros Azotobacter y Azospirillum a partir de la rizósfera de cultivos de algodón en el Espinal (Tolima. Las poblaciones microbianas se caracterizaron fenotípicamente en los medios de cultivo semiespecíficos: Ashby y LG (Azotobacter sp. y NFb, LGI y Batata (Azospirillum sp.. La promoción de crecimiento vegetal se determinó mediante la actividad de la enzima nitrogenasa por medio de la técnica de reducción de acetileno y producción de índoles por el método colorimétrico de Salkowsky. Se obtuvieron 9 aislamientos tentativos de Azotobacter sp. y 4 de Azospirillum sp. Se presentaron diferencias significativas en la prueba de reducción de acetileno con las cepas presuntivas de Azotobacter sp.: NAT 9 (206.43 nmol C2H2 mL-1.h-1, NAT 4, (292.77 nmol C2H2 mL-1.h-1, y NAT 6 (460.60 nmol C2H2 mL-1.h-1 y en la producción de índoles de las cepas NAT 19 (19.87 μg.mL-1 y NAT 13 (20.08 μg.mL-1. Por su eficiencia in vitro en la promoción de crecimiento vegetal se seleccionaron las cepas NAT9, NAT4, NAT6, NAT19 y NAT13 para ser evaluadas como principio activo en futuros inoculantes para el algodón en esta zona del departamento del Tolima. Palabras clave: fijación biológica de nitrógeno; producción de índoles; promoción del crecimiento

  8. Antioxidant activity of Sphaerococcus coronopifolius associated bacteria

    Directory of Open Access Journals (Sweden)

    Nádia Fino

    2014-06-01

    Full Text Available Associated bacteria living on macroalgae surfaces are an interesting source of new secondary metabolites with biological activities. The aim of this study was the isolation and identification of epiphytic bacteria from the marine algae Sphaerococcus coronopifolius and the evaluation of the antioxidant activity of the bacteria extracts. The identification of epiphytic bacteria was determined by 16S rRNA gene sequencing. Bacteria extracts were obtained with methanol and dichloromethane (1:1 extraction. Antioxidant activity was evaluated by quantification of total phenolic content (TPC, 2,2-diphenyl-1-picrylhydrazyl (DPPH radical scavenging activity and oxygen radical absorbent capacity (ORAC. The extracts with higher antioxidant activity were tested on MCF-7 and HepG-2 cell lines in oxidative stress conditions induced by H2O2 at 0.2 mM and 0.5 mM, respectively. In total were isolated 21 Sphaerococcus coronopifolius associated bacteria and identified as Vibrio sp. (28.57%, Shewanella sp. (23.81%, Pseudoalteromonas sp. (19.05%, Bacillus sp. (9.52% and Halomonas sp. (9.52%. Two (9.52% of them presented less than 90% Basic Local Alignment Search Tool (BLAST match. The epiphytic bacteria with the most antioxidant potential evaluated by ORAC and DPPH methods were Sp2, Sp12, Sp23, Sp25 and Sp27. The strain Sp4 show high antioxidant activity in all antioxidant methods (ORAC, DPPH and TPC. In oxidative stress conditions on MCF-7 cell line, the extracts of bacteria (1mg.ml-1: 24hours Sp4 (16.15%, Sp25 (17.95% and Sp27 (10.65% prevented the cell death induced by H2O2. In the HepG-2 cell line was the extracts of Sp2 (9.01%, Sp4 (11.21%, Sp12 (7.20% and Sp23 (8.81% bacteria that high prevented the oxidative stress condition induced by H2O2. In conclusion, the Sphaerococcus coronopifolius associated bacteria can be an interesting and excellent source of marine natural compounds with antioxidant activity.

  9. Comportamiento de la neumonía asociada a la ventilación artificial en hospital pediátrico “Mártires de Las Tunas”, 2010-2011

    Directory of Open Access Journals (Sweden)

    Julio Alberto Rueda Escobar

    2015-12-01

    Full Text Available Con el objetivo de realizar una caracterización del comportamiento de los niños que adquirieron neumonía durante la ventilación artificial, se realizó un estudio descriptivo, de corte transversal, en los pacientes ingresados en la unidad de cuidados intensivos del Hospital Pediátrico Provincial “Mártires de las Tunas”, durante el periodo comprendido de  enero del 2010 a diciembre del 2011. Se encontró que los menores de dos años y del sexo masculino fueron los que con mayor frecuencia desarrollaron neumonía asociada a la ventilación artificial; la desnutrición estuvo presente en el 58,8% de los niños infectados; los traumatismos, las infecciones respiratorias y el shock fueron las principales causas de ventilación; la klebsiella, la pseudomona y  enterobacter fueron los gérmenes que se aislaron con mayor frecuencia en el tubo endotraqueal y el hemocultivo. La mayoría de los pacientes que desarrollaron neumonía nosocomial permanecieron en ventilación más de siete días y sólo dos fallecieron.

  10. Modelo auto-regresivo aplicado a la eliminación de ruidos de los mapas de anomalías de resistividad en fosfatos asociadas a bolsones estériles

    Directory of Open Access Journals (Sweden)

    Saad Bakkali

    2008-03-01

    Full Text Available Actualmente se emplean varios métodos para perfeccionar los bordes y contornos de mapas geofísicos. En Marruecos se realizó una prospección de fosfatos empleando el método eléctrico de resistividad; para ello se utilizó un dispositivo Schlumberger, cubriendo una superficie de 50 hectáreas, con el objetivo de detectar anomalías asociadas a bolsones estériles en los depósitos de fosfatos. Para la eliminación del ruido blanco se empleó un método basado en un modelo auto-regresivo (ARM, siglas en inglés; este se implementó por medio del algoritmo AutoSignal; el resultado muestra que el método ARM es efectivo para el filtrado, atenúa considerablemente el ruido producido por bolsones dispersos y de pequeño tamaño, además brinda una reducción considerable de la distorsión de la forma de la señal de resistividad original.

  11. Pustulosis exantemática aguda generalizada asociada a Epstein Barr: A propósito de un caso. Acute generalized exanthematous pustulosis associated to Epstein Barr: A propose of a case

    Directory of Open Access Journals (Sweden)

    A L Scaglione

    2008-12-01

    Full Text Available La pustulosis exantemática aguda generalizada (PEAG es una rara afección de hipersensibilidad, inducida principalmente por drogas y se manifiesta por una erupción aguda de pústulas estériles, acompañada de fiebre, que regresa en pocos días luego de discontinuar el fármaco causante. Se comunica el caso de una paciente de 23 años de edad, sin antecedentes de psoriasis que consulta por fiebre y una erupción pustulosa generalizada, asociada a la ingesta previa de amoxicilina y ácido clavulánico en el contexto de una mononucleosis infecciosa, con resolución espontánea del cuadro. El cultivo microbiológico no objetivó gérmenes patógenos.Acute generalized exanthematous pustulosis (AGEP is a rare skin eruption most commonly caused by medications. It is characterized by an acute eruption of sterile pustules and it is accompanied by an episode of fever, which regresses a few days after discontinuation of the drug that caused the condition. We report a case 23 year-old woman without history of psoriasis, that consults for fever and an acute generalized pustular eruption after amoxicillin, with clavulanic acid administration in a mononucleosis infection context, which resolved spontaneously. The microbiologic culture was negative for pathogenic germens.

  12. Redefinición del concepto y del abordaje de las lesiones por humedad: Una propuesta conceptual y metodológica para mejorar el cuidado de las lesiones cutáneas asociadas a la humedad (LESCAH

    Directory of Open Access Journals (Sweden)

    Joan-Enric Torra i Bou

    2013-06-01

    Full Text Available Actualmente se percibe una indefinición manifiesta acerca de la conceptualización y abordaje de las llamadas lesiones por humedad en los entornos clínicos, docentes e investigadores de nuestro país, que muy frecuentemente relacionan este término solo con las lesiones producidas por la orina y las heces. Dadas las diversas repercusiones que se intuye pueden tener este tipo de lesiones, se hace necesario consensuar y unificar los distintos aspectos relacionados con el cuidado de estas heridas. En el presente artículo, y siguiendo la tendencia internacional, se propone la adopción del término lesiones cutáneas asociadas a la humedad (LESCAH para referirnos a la inflamación y erosión de la piel causada por la exposición prolongada a diversas fuentes de humedad, incluyendo la orina o las heces, el sudor, el exudado de la herida, el moco o la saliva. Desde esta premisa, se presentan y describen los diferentes tipos de LESCAH identificados en la clínica. Y finalmente, para facilitar la integración de la valoración, prevención y tratamiento de los pacientes con algún tipo de LESCAH, se propone un plan básico de actuación -denominado con el acrónimo CASPROT- con los distintos objetivos e intervenciones a realizar en cada fase.

  13. Flagellated ectosymbiotic bacteria propel a eucaryotic cell.

    Science.gov (United States)

    Tamm, S L

    1982-09-01

    A devescovinid flagellate from termites exhibits rapid gliding movements only when in close contact with other cells or with a substrate. Locomotion is powered not by the cell's own flagella nor by its remarkable rotary axostyle, but by the flagella of thousands of rod bacteria which live on its surface. That the ectosymbiotic bacteria actually propel the protozoan was shown by the following: (a) the bacteria, which lie in specialized pockets of the host membrane, bear typical procaryotic flagella on their exposed surface; (b) gliding continues when the devescovinid's own flagella and rotary axostyle are inactivated; (c) agents which inhibit bacterial flagellar motility, but not the protozoan's motile systems, stop gliding movements; (d) isolated vesicles derived from the surface of the devescovinid rotate at speeds dependent on the number of rod bacteria still attached; (e) individual rod bacteria can move independently over the surface of compressed cells; and (f) wave propagation by the flagellar bundles of the ectosymbiotic bacteria is visualized directly by video-enhanced polarization microscopy. Proximity to solid boundaries may be required to align the flagellar bundles of adjacent bacteria in the same direction, and/or to increase their propulsive efficiency (wall effect). This motility-linked symbiosis resembles the association of locomotory spirochetes with the Australian termite flagellate Mixotricha (Cleveland, L. R., and A. V. Grimstone, 1964, Proc. R. Soc. Lond. B Biol. Sci., 159:668-686), except that in our case propulsion is provided by bacterial flagella themselves. Since bacterial flagella rotate, an additional novelty of this system is that the surface bearing the procaryotic rotary motors is turned by the eucaryotic rotary motor within.

  14. The Effect of Bacteria Penetration on Chalk Permeability

    DEFF Research Database (Denmark)

    Halim, Amalia Yunita; Shapiro, Alexander; Nielsen, Sidsel Marie;

    into reservoirs, however, a complete understanding of the penetration behavior of bacteria is lacking, especially in chalk formations where the pore throat sizes are almost comparable with the sizes of bacteria vegetative cells. This study investigates the penetration of bacteria into chalk. Two bacteria types...

  15. Morphological plasticity of bacteria-Open questions.

    Science.gov (United States)

    Shen, Jie-Pan; Chou, Chia-Fu

    2016-05-01

    Morphological plasticity of bacteria is a cryptic phenomenon, by which bacteria acquire adaptive benefits for coping with changing environments. Some environmental cues were identified to induce morphological plasticity, but the underlying molecular mechanisms remain largely unknown. Physical and chemical factors causing morphological changes in bacteria have been investigated and mostly associated with potential pathways linked to the cell wall synthetic machinery. These include starvation, oxidative stresses, predation effectors, antimicrobial agents, temperature stresses, osmotic shock, and mechanical constraints. In an extreme scenario of morphological plasticity, bacteria can be induced to be shapeshifters when the cell walls are defective or deficient. They follow distinct developmental pathways and transform into assorted morphological variants, and most of them would eventually revert to typical cell morphology. It is suggested that phenotypic heterogeneity might play a functional role in the development of morphological diversity and/or plasticity within an isogenic population. Accordingly, phenotypic heterogeneity and inherited morphological plasticity are found to be survival strategies adopted by bacteria in response to environmental stresses. Here, microfluidic and nanofabrication technology is considered to provide versatile solutions to induce morphological plasticity, sort and isolate morphological variants, and perform single-cell analysis including transcriptional and epigenetic profiling. Questions such as how morphogenesis network is modulated or rewired (if epigenetic controls of cell morphogenesis apply) to induce bacterial morphological plasticity could be resolved with the aid of micro-nanofluidic platforms and optimization algorithms, such as feedback system control. PMID:27375812

  16. Molecular analysis of deep subsurface bacteria

    International Nuclear Information System (INIS)

    Deep sediments samples from site C10a, in Appleton, and sites, P24, P28, and P29, at the Savannah River Site (SRS), near Aiken, South Carolina were studied to determine their microbial community composition, DNA homology and mol %G+C. Different geological formations with great variability in hydrogeological parameters were found across the depth profile. Phenotypic identification of deep subsurface bacteria underestimated the bacterial diversity at the three SRS sites, since bacteria with the same phenotype have different DNA composition and less than 70% DNA homology. Total DNA hybridization and mol %G+C analysis of deep sediment bacterial isolates suggested that each formation is comprised of different microbial communities. Depositional environment was more important than site and geological formation on the DNA relatedness between deep subsurface bacteria, since more 70% of bacteria with 20% or more of DNA homology came from the same depositional environments. Based on phenotypic and genotypic tests Pseudomonas spp. and Acinetobacter spp.-like bacteria were identified in 85 million years old sediments. This suggests that these microbial communities might have been adapted during a long period of time to the environmental conditions of the deep subsurface

  17. COMPETITION BETWEEN ANOXYGENIC PHOTOTROPHIC BACTERIA AND COLORLESS SULFUR BACTERIA IN A MICROBIAL MAT

    NARCIS (Netherlands)

    VISSCHER, PT; VANDENENDE, FP; SCHAUB, BEM; VANGEMERDEN, H

    1992-01-01

    The populations of chemolithoautotrophic (colorless) sulfur bacteria and anoxygenic phototrophic bacteria were enumerated in a marine microbial mat. The highest population densities were found in the 0-5 mm layer of the mat: 2.0 X 10(9) cells CM-3 sediment, and 4.0 X 10(7) cells cm-3 sediment for th

  18. Method of Detecting Coliform Bacteria and Escherichia Coli Bacteria from Reflected Light

    Science.gov (United States)

    Vincent, Robert (Inventor)

    2013-01-01

    The present invention relates to a method of detecting coliform bacteria in water from reflected light and a method of detecting Eschericha Coli bacteria in water from reflected light, and also includes devices for the measurement, calculation and transmission of data relating to that method.

  19. Nutritional Interdependence Among Rumen Bacteria During Cellulose Digestion In Vitro

    OpenAIRE

    Miura, Hideki; HORIGUCHI, Masaaki; Ogimoto, Keiji; MATSUMOTO, Tatsuro

    1983-01-01

    A study has been made of the promoting effect of starch on cellulose digestion by mixed rumen bacteria in a cellulose-urea medium. Starch supplementation of the medium promoted the growth of bacteria that required neither amino acids (AA) nor branched-chain fatty acids (BrFA). The growth of these bacteria was followed by the growth of AA-dependent bacteria, AA- or BrFA-dependent bacteria, BrFA-producing bacteria, and finally, BrFA-dependent cellulolytic bacteria. Population changes of these b...

  20. Fossil bacteria in Xuanlong iron ore deposits of Hebei Province

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Discovered in Early Proterozoic Xuanlong iron ore deposits are six genera of fossil iron bacteria, i. e. sphere (coenobium of) rod-shaped (monomer) Naumanniella, ellipsoid elliptical Ochrobium, sphere spherical Siderocapsa and chain spherical Siderococcus, chain rod-shaped Leptothrix and Lieskeella, and six genera of fossil blue bacteria, namely sphere spherical Gloeocapsa, Synechocystis and Globobacter, chain spherical Anabaena and Nostoc, and constrictive septate tubular Nodularia. The biomineralized monomers and coenobia of the two categories of bacteria, together with hematite plates made up the bacteria pelletal, bacteria silky,bacteria fibrous and clasty bacteria pelletal textural lamina. The bacteria pelletal laminae combined with other bacteria laminae to make up oncolite, stromatolite and laminate. The precipitation of iron oxide was accelerated due to iron and blue bacteria cohabiting on microbial film or mat. The Xuanlong iron ore deposits are microbial binding ore deposits of ocean source.

  1. Studies on ultrasmall bacteria in relation to the presence of bacteria in the stratosphere

    Science.gov (United States)

    Alshammari, Fawaz; Wainwright, Milton; Alabri, Khalid; Alharbi, Sulamain A.

    2011-04-01

    Recent studies confirm that bacteria exist in the stratosphere. It is generally assumed that these bacteria are exiting from Earth, although it is possible that some are incoming from space. Most stratospheric bacterial isolates belong to the spore-forming genus Bacillus, although non-spore formers have also been isolated. Theoretically, the smaller a bacterium is, the more likely it is to be carried from Earth to the stratosphere. Ultrasmall bacteria have been frequently isolated from Earth environments, but not yet from the stratosphere. This is an anomalous situation, since we would expect such small bacteria to be over represented in the stratosphere-microflora. Here, we show that ultrasmall bacteria are present in the environment on Earth (i.e. in seawater and rainwater) and discuss the paradox of why they have not been isolated from the stratosphere.

  2. Using Fluorescent Viruses for Detecting Bacteria in Water

    Science.gov (United States)

    Tabacco, Mary Beth; Qian, Xiaohua; Russo, Jaimie A.

    2009-01-01

    A method of detecting water-borne pathogenic bacteria is based partly on established molecular-recognition and fluorescent-labeling concepts, according to which bacteria of a species of interest are labeled with fluorescent reporter molecules and the bacteria can then be detected by fluorescence spectroscopy. The novelty of the present method lies in the use of bacteriophages (viruses that infect bacteria) to deliver the fluorescent reporter molecules to the bacteria of the species of interest.

  3. Bacteriocins From Lactic Acid Bacteria: Interest For Food Products Biopreservation

    OpenAIRE

    Dortu, C.; Thonart, Philippe

    2009-01-01

    Bacteriocins from lactic acid bacteria: interest for food products biopreservation. Bacteriocins from lactic acid bacteria are low molecular weight antimicrobial peptides. They have inhibitory activity against the bacteria that are closed related to the producer strains and a narrow inhibitory spectrum. Nevertheless, most of them have activity against some food-born pathogenic bacteria as Listeria monocytogenes. The application of bacteriocins or bacteriocin producing lactic acid bacteria in ...

  4. All ecosystems potentially host electrogenic bacteria.

    Science.gov (United States)

    Chabert, Nicolas; Amin Ali, Oulfat; Achouak, Wafa

    2015-12-01

    Instead of requiring metal catalysts, MFCs utilize bacteria that oxidize organic matter and either transfer electrons to the anode or take electrons from the cathode. These devices are thus based on a wide microbial diversity that can convert a large array of organic matter components into sustainable and renewable energy. A wide variety of explored environments were found to host electrogenic bacteria, including extreme environments. In the present review, we describe how different ecosystems host electrogenic bacteria, as well as the physicochemical, electrochemical and biological parameters that control the currents from MFCs. We also report how using new molecular techniques allowed characterization of electrochemical biofilms and identification of potentially new electrogenic species. Finally we discuss these findings in the context of future research directions. PMID:26298511

  5. Inorganic nanoparticles engineered to attack bacteria.

    Science.gov (United States)

    Miller, Kristen P; Wang, Lei; Benicewicz, Brian C; Decho, Alan W

    2015-11-01

    Antibiotics were once the golden bullet to constrain infectious bacteria. However, the rapid and continuing emergence of antibiotic resistance (AR) among infectious microbial pathogens has questioned the future utility of antibiotics. This dilemma has recently fueled the marriage of the disparate fields of nanochemistry and antibiotics. Nanoparticles and other types of nanomaterials have been extensively developed for drug delivery to eukaryotic cells. However, bacteria have very different cellular architectures than eukaryotic cells. This review addresses the chemistry of nanoparticle-based antibiotic carriers, and how their technical capabilities are now being re-engineered to attack, kill, but also non-lethally manipulate the physiologies of bacteria. This review also discusses the surface functionalization of inorganic nanoparticles with small ligand molecules, polymers, and charged moieties to achieve drug loading and controllable release.

  6. Urban ants and transportation of nosocomial bacteria.

    Science.gov (United States)

    Rodovalho, Cynara M; Santos, Ana L; Marcolino, Marcus T; Bonetti, Ana M; Brandeburgo, Malcon A M

    2007-01-01

    Many ant species displaying synanthropic behavior that have successfully dispersed in urban areas can cause problems in hospitals by acting as bacterial vectors. In this study, we encountered bacteria on ants collected at the Universidade Federal de Uberlândia hospital, in the campus and at households nearby. The ants were identified as Tapinoma melanocephalum (Fabricius) and Camponotus vittatus (Forel) (Hymenoptera: Formicidae) and the bacterial strains found here belong to the group of the coagulase-positive staphylococcus, coagulase-negative staphylococcus and gram negative bacilli, including antimicrobial drug-resistant strains. An investigation of the bacteria found in the ants and in the environment revealed that some ants carried non-isolated bacteria from the same environment and with high levels of resistance, evidencing the transmission potential of these insects. PMID:17710329

  7. Lethal photosensitization of biofilm-grown bacteria

    Science.gov (United States)

    Wilson, Michael

    1997-12-01

    Antibacterial agents are increasingly being used for the prophylaxis and treatment of oral diseases. As these agents can be rendered ineffective by resistance development in the target organisms there is a need to develop alternative antimicrobial approaches. Light-activated antimicrobial agents release singlet oxygen and free radicals which can kill adjacent bacteria and a wide range of cariogenic and periodontopathogenic bacteria has been shown to be susceptible to such agents. In the oral cavity these organisms are present as biofilms (dental plaques) which are less susceptible to traditional antimicrobial agents than bacterial suspensions. The results of these studies have shown that biofilm-grown oral bacteria are also susceptible to lethal photosensitization although the light energy doses required are grater than those needed to kill the organisms when they are grown as aqueous suspensions.

  8. Copper tolerance and virulence in bacteria

    Science.gov (United States)

    Ladomersky, Erik; Petris, Michael J.

    2015-01-01

    Copper (Cu) is an essential trace element for all aerobic organisms. It functions as a cofactor in enzymes that catalyze a wide variety of redox reactions due to its ability to cycle between two oxidation states, Cu(I) and Cu(II). This same redox property of copper has the potential to cause toxicity if copper homeostasis is not maintained. Studies suggest that the toxic properties of copper are harnessed by the innate immune system of the host to kill bacteria. To counter such defenses, bacteria rely on copper tolerance genes for virulence within the host. These discoveries suggest bacterial copper intoxication is a component of host nutritional immunity, thus expanding our knowledge of the roles of copper in biology. This review summarizes our current understanding of copper tolerance in bacteria, and the extent to which these pathways contribute to bacterial virulence within the host. PMID:25652326

  9. Distribución Diferencial de Bacterias con Potencial Biocontrolador de Spongospora subterranea en Plantas de Papa (Solanum tuberosum cv. Diacol Capiro Differential Distrubution of Candidadate Biocontrol Bacteria against Spongospora subterranea in Potato Plants (Solanum tuberosum cv. Diacol Capiro

    Directory of Open Access Journals (Sweden)

    Juliana Soler Arango

    2012-06-01

    Full Text Available Resumen. La búsqueda de microorganismos promisorios para biocontrol de patógenos de plantas en el suelo con frecuencia se ha orientado a la detección de productores de hormonas y enzimas líticas, condiciones asociadas a su capacidad para promover crecimiento vegetal. Sin embargo, el suelo es altamente variable en escalas pequeñas y se conoce poco sobre la distribución espacial de microorganismos que expresan esas funciones. Este estudio determinó la capacidad de producción de indoles totales y quitinasas en bacterias cultivables aisladas del interior de la raíz, la rizósfera, la superficie de los tubérculos o suelo de un cultivo de papa (Solanum tuberosum variedad Diacol Capiro. Las muestras se obtuvieron en un campo comercial en el municipio de la Unión en el departamento de Antioquia, Colombia, en plantas que presentaban síntomas de infección por Spongospora subterranea. Se encontró una producción diferencial de indoles o quitinasas según el sitio de aislamiento de las bacterias. No se encontró una alta producción de ambas actividades en un sólo aislamiento, la mayor producción de indoles totales y quitinasas se encontró en bacterias aisladas a partir de raíz y rizósfera, comparada con las aisladas de tubérculos y suelo. Estos resultados sugieren que en el suelo no es aleatoria la distribución de funciones deseables en controladores biológicos. Con estos resultados es posible orientar su búsqueda para optimizar el uso de recursos y el desarrollo de nuevos bioproductos.Abstract. Searching for promising microorganisms to biocontrol soil-borne plant pathogens has been often focused on producers of hormone and lytic enzymes, since these traits are linked to plant growth promotion. However, the environment from inner roots to bulk soil is quite variable, and little is known about the spatial distribution of microorganisms expressing these desirable traits. Using potato plants (Solanum tuberosum var. Diacol Capiro from a

  10. Biodegradation of Complex Bacteria on Phenolic Derivatives in River Water

    Institute of Scientific and Technical Information of China (English)

    GUANG-HUA LU; CHAO WANG; ZHE SUN

    2009-01-01

    Objective To isolate, incubate, and identify 4-chlorophenol-degrading complex bacteria, determine the tolerance of these bacteria to phenolic derivatives and study their synergetic metabolism as well as the aboriginal microbes and co-metabolic degradation of mixed chlorophenols in river water. Methods Microbial community of complex bacteria was identified by plate culture observation techniques and Gram stain method. Bacterial growth inhibition test was used to determine the tolerance of complex bacteria to toxicants. Biodegradability of phenolic derivatives was determined by adding 4-chlorophenol-degrading bacteria in river water. Results The complex bacteria were identified as Mycopiana, Alcaligenes, Pseudvmonas, and Flavobacterium. The domesticated complex bacteria were more tolerant to phenolic derivatives than the aboriginal bacteria from Qinhuai River. The biodegradability of chlorophenols, dihydroxybenzenes and nitrophenols under various aquatic conditions was determined and compared. The complex bacteria exhibited a higher metabolic efficiency on chemicals than the aboriginal microbes, and the final removal rate of phenolic derivatives was increased at least by 55% when the complex bacteria were added into river water. The metabolic relationship between dominant mixed bacteria and river bacteria was studied. Conclusion The complex bacteria domesticated by 4-chlorophenol can grow and be metabolized to take other chlorophenols, dihydroxybenzenes and nitrophenols as the sole carbon and energy source. There is a synergetic metabolism of most compounds between the aboriginal microbes in river water and the domesticated complex bacteria. 4-chlorophenol-degrading bacteria can co-metabolize various chlorophenols in river water.

  11. Bacteriophage biosensors for antibiotic-resistant bacteria.

    Science.gov (United States)

    Sorokulova, Irina; Olsen, Eric; Vodyanoy, Vitaly

    2014-03-01

    An increasing number of disease-causing bacteria are resistant to one or more anti-bacterial drugs utilized for therapy. Early and speedy detection of these pathogens is therefore very important. Traditional pathogen detection techniques, that include microbiological and biochemical assays are long and labor-intensive, while antibody or DNA-based methods require substantial sample preparation and purification. Biosensors based on bacteriophages have demonstrated remarkable potential to surmount these restrictions and to offer rapid, efficient and sensitive detection technique for antibiotic-resistant bacteria.

  12. Bacteria-Triggered Release of Antimicrobial Agents

    DEFF Research Database (Denmark)

    Komnatnyy, Vitaly V.; Chiang, Wen-Chi; Tolker-Nielsen, Tim;

    2014-01-01

    Medical devices employed in healthcare practice are often susceptible to microbial contamination. Pathogenic bacteria may attach themselves to device surfaces of catheters or implants by formation of chemically complex biofilms, which may be the direct cause of device failure. Extracellular...... material is demonstrated by the bacteria‐triggered release of antibiotics to control bacterial populations and signaling molecules to modulate quorum sensing. The self‐regulating system provides the basis for the development of device‐relevant polymeric materials, which only release antibiotics...... in dependency of the titer of bacteria surrounding the medical device....

  13. Bacteria Provide Cleanup of Oil Spills, Wastewater

    Science.gov (United States)

    2010-01-01

    Through Small Business Innovation Research (SBIR) contracts with Marshall Space Flight Center, Micro-Bac International Inc., of Round Rock, Texas, developed a phototrophic cell for water purification in space. Inside the cell: millions of photosynthetic bacteria. Micro-Bac proceeded to commercialize the bacterial formulation it developed for the SBIR project. The formulation is now used for the remediation of wastewater systems and waste from livestock farms and food manufacturers. Strains of the SBIR-derived bacteria also feature in microbial solutions that treat environmentally damaging oil spills, such as that resulting from the catastrophic 2010 Deepwater Horizon oil rig explosion in the Gulf of Mexico.

  14. Functional Encyclopedia of Bacteria and Archaea

    Energy Technology Data Exchange (ETDEWEB)

    Blow, M. J.; Deutschbauer, A. M.; Hoover, C. A.; Lamson, J.; Lamson, J.; Price, M. N.; Waters, J.; Wetmore, K. M.; Bristow, J.; Arkin, A. P.

    2013-03-20

    Bacteria and Archaea exhibit a huge diversity of metabolic capabilities with fundamental importance in the environment, and potential applications in biotechnology. However, the genetic bases of these capabilities remain unclear due largely to an absence of technologies that link DNA sequence to molecular function. To address this challenge, we are developing a pipeline for high throughput annotation of gene function using mutagenesis, growth assays and DNA sequencing. By applying this pipeline to annotate gene function in 50 diverse microbes we hope to discover thousands of new gene functions and produce a proof of principle `Functional Encyclopedia of Bacteria and Archaea?.

  15. DNA Barcoding on Bacteria: A Review

    Directory of Open Access Journals (Sweden)

    D. E. Lebonah

    2014-01-01

    Full Text Available Bacteria are omnipotent and they can be found everywhere. The study of bacterial pathogens has been happening from olden days to prevent epidemics, food spoilage, losses in agricultural production, and loss of lives. Modern techniques in DNA based species identification are considered. So, there is a need to acquire simple and quick identification technique. Hence, this review article covers the efficacy of DNA barcoding of bacteria. Routine DNA barcoding involves the production of PCR amplicons from particular regions to sequence them and these sequence data are used to identify or “barcode” that organism to make a distinction from other species.

  16. Pervasive transcription: detecting functional RNAs in bacteria.

    Science.gov (United States)

    Lybecker, Meghan; Bilusic, Ivana; Raghavan, Rahul

    2014-01-01

    Pervasive, or genome-wide, transcription has been reported in all domains of life. In bacteria, most pervasive transcription occurs antisense to protein-coding transcripts, although recently a new class of pervasive RNAs was identified that originates from within annotated genes. Initially considered to be non-functional transcriptional noise, pervasive transcription is increasingly being recognized as important in regulating gene expression. The function of pervasive transcription is an extensively debated question in the field of transcriptomics and regulatory RNA biology. Here, we highlight the most recent contributions addressing the purpose of pervasive transcription in bacteria and discuss their implications.

  17. Factores de riesgo de infecciones del tracto sanguíneo asociadas a alimentación parenteral en pacientes pediátricos Risk factors of bloodstream infections associated with parenteral nutrition in pediatric patients

    Directory of Open Access Journals (Sweden)

    P. Balboa Cardemil

    2011-12-01

    Full Text Available Introducción: Una de las complicaciones de la nutrición parenteral (NP es la infección sanguínea (IS asociada a catéter, se desconoce los factores de riesgo más importantes en nuestro medio. Objetivo: Determinar los factores de riesgo de las IS asociadas a NP en pacientes pediátricos en hospitales de Santiago de Chile. Pacientes y métodos: En 2 hospitales públicos se analizaron retrospectivamente todos los recién nacidos (RN y niños que recibieron NP entre enero del 2002 y diciembre del 2005. El grupo estudio (GE son todos aquellos con hemocultivos (+ durante la administración de NP. El grupo control (GC correspondió a 2 controles por cada caso, niños con NP y hemocultivos (-. Para el análisis estadístico se usaron pruebas paramétricas, no paramétricas y regresión logística. Resultados: Se obtuvieron 58 casos y 130 controles. Los niños del GE recibieron NP por más tiempo que GC: 24 (7-934 vs 10 días (7-152 (p Introduction: One of the complications of parenteral nutrition (PN is bloodstream infection (BSI associated with catheter, unknown the most important risk factors in our country. Objective: To determine risk factors of BSI associated with PN in pediatric patients in public hospitals of Santiago, Chile. Patients and methods: In two public hospitals all newborns and children receiving PN were analyzed retrospectively, from January 2002 to December 2005. The study group (SG was formed by all those with blood cultures (+ during the administration of PN. We selected two controls for each case, children with PN and blood cultures (- (control group, CG. We used parametric, nonparametric and logistic regression to analyze data. Results: There were 58 cases and 130 controls. Children of the SG received PN for longer days than CG: 24 (7-934 vs. 10 days (7-152 (p < 0.001, presented a higher rate of malnutrition (44.4% vs. 31%, chi2, p < 0.05 and received more frequently PN by central venous catheter than peripheral catheter (GE

  18. Risk factors of HIV-related oral lesions in adults Factores de riesgo de lesiones bucales asociadas al VIH en adultos Fatores de risco de lesões bucais associadas ao HIV em adultos

    Directory of Open Access Journals (Sweden)

    Maria Noel Marzano Rodrigues Petruzzi

    2013-02-01

    Full Text Available OBJECTIVE: To assess the risk factors in the occurrence of oral lesions in HIV-positive adults. METHODS: A retrospective analytical-descriptive survey was conducted using the medical/dental records of 534 patients with oral lesions associated with HIV. The data were collected from five referral centers for managing HIV and associated comorbidities in the city of Porto Alegre, Southern Brazil, between 1996 and 2011. Using a standardized form, socio-demographic and clinical data were recorded. Exclusively and definitively diagnosed oral pathologies were included and classified according to ECC criteria on Oral Problems Related to HIV Infection. For data analysis cross-tabulations, Chi-squared tests and logistic regression models were used where appropriate. RESULTS: CD4+ counts lower than 350 cells/mm³ (p OBJETIVO: Analizar factores de riesgo para la ocurrencia de lesiones bucales en adultos seropositivos para VIH. MÉTODOS: Estudio transversal, descriptivo analítico de prontuarios médicos/odontológicos de 534 pacientes con lesiones bucales asociadas al VIH en Porto Alegre, RS, Brasil, en el período de 1996 a 2011. Los datos se colectaron en cinco centros de referencia en salud para la atención de portadores del VIH y comorbilidades asociadas. Los datos sociodemográficos y clínico-laboratoriales se colectaron en formularios estandarizados. Se incluyeron datos exclusivamente de lesiones con diagnóstico y clasificadas de acuerdo con los criterios de la ECC on Oral Problems Related to HIV Infection. El análisis de los datos fue realizado mediante la aplicación de tabulaciones cruzadas, prueba de Chi-cuadrado y modelos de regresión logística. RESULTADOS: Niveles de CD4+ 5.000 copias/mm³ (p = 0,003 y tabaquismo (p = 0,005. CONCLUSIONES: Grados de inmunodeficiencia moderados y severos y cargas virales detectables fueron factores de riesgo para el desarrollo de lesiones bucales. El consumo de tabaco y alcohol aumentó la susceptibilidad de

  19. Valor de los metodos directos e indirectos de diagnóstico en las micosis sitémicas asociadas al SIDA Efficacy of different diagnosis methods in systemic mycoses associated with AIDS

    Directory of Open Access Journals (Sweden)

    A.I. Arechavala

    1993-04-01

    Full Text Available Durante 5 años se estudiaron 117 pacientes con micosis sistémicas asociadas al SIDA: 74 criptococosis, 39 histoplasmosis y 4 con ambas enfermedades. Para el diagnóstico analizamos los siguientes materiales: escarificaciones de lesiones cutáneas o mucosas, aspirados de médula ósea, secreciones bronquiales, biopsias de diversos órganos, líquido cefalorraquídeo, hemocultivos y sueros para determinaciones serológicas. Fueron estudiadas en total 203 muestras de pacientes con histoplasmosis, el 46.3% de las mismas acusó la presencia de H. capsulatum. Las escarificaciones cutáneas exhibieron la mayor sensibilidad (94.7%, seguidas por las biopsias (80% y los mielocultivos (42.1%. La demostración de anticuerpos circulantes por medio de 3 pruebas serológicas y con de 2 antígenos específicos dio resultados positivos en el 45.4% de los pacientes. Se estudiaron en total 413 especímenes de pacientes con criptococosis, la confirmación diagnóstica fue posible en el 69% de las muestras. El mayor rendimiento se obtuvo con el LCR (89.5%, le seguieron en sensibilidad los hemocultivos (61.2%, las escarificaciones cutáneas (42.9% y los urocultivos (41.7%. La búsqueda de antígeno en los fluidos orgánicos fue positiva en casi todos los casos. La revisión que presentamos permitirá una búsqueda más racional y rápida de los métodos de diagnóstico en las micosis asociadas al SIDA.One hundred and seventeen patients suffering systemic mycosis and AIDS were studied during 5 years in the Muñiz Hospital of Buenos Aires City. Seventy four of them presented cryptococcosis, 39 histoplasmosis and 4 both mycoses. The following specimens were studied for the diagnosis: skin and mucous membrane scrapings, bone marrow aspirations, bronchial secretions, biopsies of different organs, cerebral spinal fluid and blood cultures. Sera were also collected for serologic tests. A total of 203 samples from patients with histoplasmosis were studied, 46.3% of them

  20. Safety and efficacy of large balloon sphincteroplasty in a third care hospital Dilatación con balón asociada a esfinterotomía, evaluación de eficacia y seguridad en un hospital terciario

    Directory of Open Access Journals (Sweden)

    Eduardo Martín-Arranz

    2012-07-01

    Full Text Available Background and aims: large balloon sphincteroplasty (LBS associated with sphincterotomy (ES has gained acceptance as a useful tool in extracting difficult bile duct stones. Our purpose was to evaluate the efficacy and safety of LBS with balloons ≥ 10 mm in clinical practice setting. Patients and methods: unicentre prospective study in a tertiary care hospital. All patients who underwent LBS associated with ES between July 2007 and March 2011 were included prospectively in a database recording clinical aspects, procedure data, outcome and complications. Success is the main outcome defined as complete stone removal documented by absence of any filling defect during a final occlusion cholangiogram and absence of clinical or radiological findings after the ERCP consistent with remaining stones. Complications as pancreatitis, cholangitis, post-ERCP bleeding, perforation and others were also measured. Results: one hundred twenty procedures were made in 109 patients with balloons ranging from 10 to 20 mm. Success rate was 91% in the first attempt and 96.7% after two procedures. Mechanical lithotripsy was only needed in one case (0.8%. Complication rate was 4.2% due to five cases of post-ERCP bleeding in high risk patients. Conclusion: large balloon sphincteroplasty associated to sphincterotomy in clinical practice is a very effective and safe technique.Introducción y objetivos: la dilatación con balón de gran tamaño asociada a esfinterotomía es un recurso cada vez más utilizado en la extracción de coledocolitiasis de gran tamaño. El objetivo de este estudio es evaluar la eficacia y seguridad de la dilatación con balones mayores de 10 mm en un entorno de práctica clínica habitual. Pacientes y métodos: estudio prospectivo en un hospital terciario. Todos los pacientes en los que se realizó dilatación con balón mayor de 10 mm asociado a esfinterotomía entre julio de 2007 y marzo de 2011 se incluyeron prospectivamente en una base de datos

  1. Bacteria in crude oil survived autoclaving and stimulated differentially by exogenous bacteria.

    Science.gov (United States)

    Gong, Xiao-Cui; Liu, Ze-Shen; Guo, Peng; Chi, Chang-Qiao; Chen, Jian; Wang, Xing-Biao; Tang, Yue-Qin; Wu, Xiao-Lei; Liu, Chun-Zhong

    2012-01-01

    Autoclaving of crude oil is often used to evaluate the hydrocarbon-degrading abilities of bacteria. This may be potentially useful for bioaugmentation and microbial enhanced oil recovery (MEOR). However, it is not entirely clear if "endogenous" bacteria (e.g., spores) in/on crude oil survive the autoclaving process, or influence subsequent evaluation of the hydrocarbon-degradation abilities of the "exogenous" bacterial strains. To test this, we inoculated autoclaved crude oil medium with six exogenous bacterial strains (three Dietzia strains, two Acinetobacter strains, and one Pseudomonas strain). The survival of the spore-forming Bacillus and Paenibacillus and the non-spore-forming mesophilic Pseudomonas, Dietzia, Alcaligenes, and Microbacterium was detected using a 16S rRNA gene clone library and terminal restriction fragment length polymorphism (T-RFLP) analysis. However, neither bacteria nor bacterial activity was detected in three controls consisting of non-inoculated autoclaved crude oil medium. These results suggest that detection of endogenous bacteria was stimulated by the six inoculated strains. In addition, inoculation with Acinetobacter spp. stimulated detection of Bacillus, while inoculation with Dietzia spp. and Pseudomonas sp. stimulated the detection of more Pseudomonas. In contrast, similar exogenous bacteria stimulated similar endogenous bacteria at the genus level. Based on these results, special emphasis should be applied to evaluate the influence of bacteria capable of surviving autoclaving on the hydrocarbon-degrading abilities of exogenous bacteria, in particular, with regard to bioaugmentation and MEOR. Bioaugmentation and MEOR technologies could then be developed to more accurately direct the growth of specific endogenous bacteria that may then improve the efficiency of treatment or recovery of crude oil. PMID:23028421

  2. Bacteria in crude oil survived autoclaving and stimulated differentially by exogenous bacteria.

    Directory of Open Access Journals (Sweden)

    Xiao-Cui Gong

    Full Text Available Autoclaving of crude oil is often used to evaluate the hydrocarbon-degrading abilities of bacteria. This may be potentially useful for bioaugmentation and microbial enhanced oil recovery (MEOR. However, it is not entirely clear if "endogenous" bacteria (e.g., spores in/on crude oil survive the autoclaving process, or influence subsequent evaluation of the hydrocarbon-degradation abilities of the "exogenous" bacterial strains. To test this, we inoculated autoclaved crude oil medium with six exogenous bacterial strains (three Dietzia strains, two Acinetobacter strains, and one Pseudomonas strain. The survival of the spore-forming Bacillus and Paenibacillus and the non-spore-forming mesophilic Pseudomonas, Dietzia, Alcaligenes, and Microbacterium was detected using a 16S rRNA gene clone library and terminal restriction fragment length polymorphism (T-RFLP analysis. However, neither bacteria nor bacterial activity was detected in three controls consisting of non-inoculated autoclaved crude oil medium. These results suggest that detection of endogenous bacteria was stimulated by the six inoculated strains. In addition, inoculation with Acinetobacter spp. stimulated detection of Bacillus, while inoculation with Dietzia spp. and Pseudomonas sp. stimulated the detection of more Pseudomonas. In contrast, similar exogenous bacteria stimulated similar endogenous bacteria at the genus level. Based on these results, special emphasis should be applied to evaluate the influence of bacteria capable of surviving autoclaving on the hydrocarbon-degrading abilities of exogenous bacteria, in particular, with regard to bioaugmentation and MEOR. Bioaugmentation and MEOR technologies could then be developed to more accurately direct the growth of specific endogenous bacteria that may then improve the efficiency of treatment or recovery of crude oil.

  3. Celiac disease (CD, ulcerative colitis (UC, and primary sclerosing cholangitis (PSC in one patient: a family study Enfermedad celiaca (EC, colitis ulcerosa (CU y colangitis esclerosante primaria (CEP asociadas en el mismo paciente: estudio familiar

    Directory of Open Access Journals (Sweden)

    V. Cadahía

    2005-12-01

    Full Text Available We discuss the case of a 17-year-old male who at the age of 7 was diagnosed with celiac disease (CD together with ulcerative colitis (UC and primary sclerosing cholangitis (PSC. The patient was treated with gluten-free diet and immunosuppressive drugs (azathioprine, and currently remains asymptomatic. The patient's younger, 12-year-old sister was diagnosed with CD when she was 1.5 years old, and at 7 years she developed type-I diabetes mellitus, which was difficult to control. A family study was made, and both parents were found to be affected with silent CD. All were DQ2 (+. In relation to the case and family study, we provide a series of comments related to CD and its complications.Presentamos el caso de un varón de 17 años, que a la edad de 7 años fue diagnosticado de enfermedad celiaca (EC junto con una colitis ulcerosa (CU y una colangitis esclerosante primaria (CEP asociadas. Fue tratado con DSG e inmuno-supresores tipo azatioprina y se encuentra asintomático en la actualidad. Su hermana menor de 12 años, fue diagnosticada de EC cuando tenía 1,5 años y a los 7 años desarrolló una DM tipo 1 de difícil control. Se realizó un estudio familiar y ambos padres están afectos de una EC silente. Todos ellos son DQ2 (+. A propósito del caso y estudio familiar, se hacen una serie de consideraciones sobre la enfermedad celiaca y el desarrollo de complicaciones.

  4. Hyperinfection by Strongyloides stercoralis probably associated with Rituximab in a patient with mantle cell lymphoma and hyper eosinophilia Hiperinfección por Strongyloides stercoralis probablemente asociada con Rituximab en una paciente con linfoma e hipereosinofilia

    Directory of Open Access Journals (Sweden)

    Renzo Nino Incani

    2010-08-01

    Full Text Available The first report to our knowledge, of hyperinfection by Strongyloides stercoralis (HS and hypereosinophilia, associated to immune suppression by Rituximab (the only drug received for the last one year and 10 months, in a patient with mantle-cell lymphoma (MCL, is presented. The patient has a 3-year history of MCL, and developed two accesses of HS during 2008, including meningitis, pneumonia and presence of larvae of S. stercoralis in the lungs. We had a unique chance to look at cytotoxicity of filariform larvae in the expectoration after Ivermectin treatment, showing immobilization and death of larvae, associated with eosinophils attached to the cuticle of the parasite.Se presenta el primer reporte, hasta donde tengamos información, de hiperinfección por Strongyloides stercoralis (HS e hipereosinofilia asociados a inmunosupresión por Rituximab (el único medicamento recibido durante 1 año y 10 meses, en un paciente con linfoma de células del manto (LCM. La paciente tuvo una historia de 3 años con LCM, y desarrolló 2 accesos de HS durante el 2008, incluyendo meningitis, neumonía y presencia de larvas de S. stercoralis en los pulmones. Se tuvo la oportunidad única de observar la citotoxicidad contra las larvas filariformes en la expectoración, luego del tratamiento con Ivermectina, mostrando la inmovilización y muerte de las larvas, asociada a la presencia de eosinófilos adheridos a la cutícula del parásito.

  5. Physiology of Haloalkaliphilic Sulfur-oxidizing Bacteria

    NARCIS (Netherlands)

    Banciu, H.L.

    2004-01-01

    The inorganic sulfur oxidation by obligate haloalkaliphilic chemolithoautotrophs was only recently discovered and investigated. These autotrophic sulfur oxidizing bacteria (SOB), capable of oxidation of inorganic sulfur compounds at moderate to high salt concentration and at high pH, can be divided

  6. Flow cytometry, fluorescent probes, and flashing bacteria

    NARCIS (Netherlands)

    Bunthof, C.J.

    2002-01-01

     


    Key words: fluorescent probes, flow cytometry, CSLM, viability, survival, microbial physiology, lactic acid bacteria, Lactococcus lactis , Lactobacillus plantarum , cheese, milk, probiotic In food industry there is a perceived need for rapid methods for detection and viability a

  7. Collective Sensing-Capacity of Bacteria Populations

    CERN Document Server

    Einolghozati, Arash; Fekri, Faramarz

    2012-01-01

    The design of biological networks using bacteria as the basic elements of the network is initially motivated by a phenomenon called quorum sensing. Through quorum sensing, each bacterium performs sensing the medium and communicating it to others via molecular communication. As a result, bacteria can orchestrate and act collectively and perform tasks impossible otherwise. In this paper, we consider a population of bacteria as a single node in a network. In our version of biological communication networks, such a node would communicate with one another via molecular signals. As a first step toward such networks, this paper focuses on the study of the transfer of information to the population (i.e., the node) by stimulating it with a concentration of special type of a molecules signal. These molecules trigger a chain of processes inside each bacteria that results in a final output in the form of light or fluorescence. Each stage in the process adds noise to the signal carried to the next stage. Our objective is ...

  8. Genetics of proteinases of lactic acid bacteria

    NARCIS (Netherlands)

    Kok, Jan; Venema, Gerhardus

    1988-01-01

    Because it is essential for good growth with concomitant rapid acid production, and for the production of flavorous peptides and amino acids, the proteolytic ability of lactic acid bacteria is of crucial importance for reliable dairy product quality. In view of this importance, considerable research

  9. Freeze-drying of lactic acid bacteria.

    Science.gov (United States)

    Fonseca, Fernanda; Cenard, Stéphanie; Passot, Stéphanie

    2015-01-01

    Lactic acid bacteria are of great importance for the food and biotechnology industry. They are widely used as starters for manufacturing food (e.g., yogurt, cheese, fermented meats, and vegetables) and probiotic products, as well as for green chemistry applications. Freeze-drying or lyophilization is a convenient method for preservation of bacteria. By reducing water activity to values below 0.2, it allows long-term storage and low-cost distribution at suprazero temperatures, while minimizing losses in viability and functionality. Stabilization of bacteria via freeze-drying starts with the addition of a protectant solution to the bacterial suspension. Freeze-drying includes three steps, namely, (1) freezing of the concentrated and protected cell suspension, (2) primary drying to remove ice by sublimation, and (3) secondary drying to remove unfrozen water by desorption. In this chapter we describe a method for freeze-drying of lactic acid bacteria at a pilot scale, thus allowing control of the process parameters for maximal survival and functionality recovery.

  10. Exopolysaccharides produced by lactic acid bacteria

    NARCIS (Netherlands)

    Caggianiello, Graziano; Kleerebezem, Michiel; Spano, Giuseppe

    2016-01-01

    A wide range of lactic acid bacteria (LAB) is able to produce capsular or extracellular polysaccharides, with various chemical compositions and properties. Polysaccharides produced by LAB alter the rheological properties of the matrix in which they are dispersed, leading to typically viscous and

  11. Discovering lactic acid bacteria by genomics

    NARCIS (Netherlands)

    Klaenhammer, T; Altermann, E; Arigoni, F; Bolotin, A; Breidt, F; Broadbent, J; Cano, R; Chaillou, S; Deutscher, J; Gasson, M; van de Guchte, M; Guzzo, J; Hartke, A; Hawkins, T; Hols, P; Hutkins, R; Kleerebezem, M; Kok, J; Kuipers, O; Maguin, E; McKay, L; Mills, D; Nauta, A; Overbeek, R; Pel, H; Pridmore, D; Saier, M; van Sinderen, D; Sorokin, A; Steele, J; O'Sullivan, D; de Vos, W; Weimer, B; Zagorec, M; Siezen, R

    2002-01-01

    This review summarizes a collection of lactic acid bacteria that are now undergoing genomic sequencing and analysis. Summaries are presented on twenty different species, with each overview discussing the organisms fundamental and practical significance, environmental habitat, and its role in ferment

  12. NSAID enteropathy and bacteria: a complicated relationship.

    Science.gov (United States)

    Syer, Stephanie D; Blackler, Rory W; Martin, Rebeca; de Palma, Giada; Rossi, Laura; Verdu, Elena; Bercik, Premek; Surette, Michael G; Aucouturier, Anne; Langella, Philippe; Wallace, John L

    2015-04-01

    The clinical significance of small intestinal damage caused by nonsteroidal anti-inflammatory drugs (NSAIDs) remains under-appreciated. It occurs with greater frequency than the damage caused by these drugs in the upper gastrointestinal tract, but is much more difficult to diagnose and treat. Although the pathogenesis of NSAID enteropathy remains incompletely understood, it is clear that bacteria, bile, and the enterohepatic circulation of NSAIDs are all important factors. However, they are also interrelated with one another. Bacterial enzymes can affect the cytotoxicity of bile and are essential for enterohepatic circulation of NSAIDs. Gram-negative bacteria appear to be particularly important in the pathogenesis of NSAID enteropathy, possibly through release of endotoxin. Inhibitors of gastric acid secretion significantly aggravate NSAID enteropathy, and this effect is due to significant changes in the intestinal microbiome. Treatment with antibiotics can, in some circumstances, reduce the severity of NSAID enteropathy, but published results are inconsistent. Specific antibiotic-induced changes in the microbiota have not been causally linked to prevention of intestinal damage. Treatment with probiotics, particularly Bifidobacterium, Lactobacillus, and Faecalibacteriaum prausnitzii, has shown promising effects in animal models. Our studies suggest that these beneficial effects are due to colonization by the bacteria, rather than to products released by the bacteria.

  13. Antimicrobial resistant bacteria in the food chain

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar

    2003-01-01

    Antimicrobials are used for treatment and prevention of disease in food animals and as feed additives for growth promotion. All uses lead to the development of resistant bacteria, some of which are pathogenic to humans. Current main concerns are with resistance in Salmonella and Campylobacter...

  14. Bioluminescent bacteria: lux genes as environmental biosensors

    OpenAIRE

    Nunes-Halldorson Vânia da Silva; Duran Norma Letícia

    2003-01-01

    Bioluminescent bacteria are widespread in natural environments. Over the years, many researchers have been studying the physiology, biochemistry and genetic control of bacterial bioluminescence. These discoveries have revolutionized the area of Environmental Microbiology through the use of luminescent genes as biosensors for environmental studies. This paper will review the chronology of scientific discoveries on bacterial bioluminescence and the current applications of bioluminescence in env...

  15. Comparative activity of ciprofloxacin against anaerobic bacteria.

    OpenAIRE

    Sutter, V L; Kwok, Y Y; Bulkacz, J

    1985-01-01

    The in vitro activity of ciprofloxacin was assessed against 362 strains of anaerobic bacteria and compared with that of cefoxitin, clindamycin, metronidazole, and mezlocillin. Only 31% of the strains tested were susceptible to ciprofloxacin. The other agents were active against most of the strains tested.

  16. Bacteria in ice may record climate change

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ To many people, bacteria and climate change are like chalk and cheese: the srnallest creature versus one of the biggest phenomena on Earth. Not really.Scientists with the CAS Institute of Tibetan Plateau Research (ITP) and coworkers recently reported that small bugs deposited in ice and snow might tell how our climate has been changing.

  17. Platinum electrodes for electrochemical detection of bacteria

    Science.gov (United States)

    Wilkins, J. R.

    1979-01-01

    Bacteria is detected electro-chemically by measuring evolution of hydrogen in test system with platinum and reference electrode. Using system, electrodes of platinum are used to detect and enumerate varieties of gram-positive and gram-negative organisms compared in different media.

  18. [Innovative treatments for multidrug-resistant bacteria].

    Science.gov (United States)

    Pierre, Tattevin; Aurélien, Lorleac'h; Matthieu, Revest

    2014-03-01

    The spread of multidrug-resistant bacteria has accelerated sharply in the last decade. According to the World Health Organization they are responsible for an estimated 25 000 deaths in Europe each year. In addition, few new antibiotics are under development, raising the spectrum of a return to the "pre-antibiotic era". Non antibiotic antibacterial agents have recently attracted renewed interest. The most promising candidates are: i) phages (bacteria-infecting viruses) have been widely used in Eastern European countries since the 1930s but come up against logistic and regulatory obstacles due to the evolutionary nature of these biologic agents, while convincing clinical data are lacking; ii) bacteriocines are smallantibacterialpeptidesproducedby numerous bacteria; some have a rapid bactericidal effect, good tolerability, and a limited impact on the commensal flora; however, clinical use of bacteriocines is complicated by their fragility, poor penetration, and substantial risk of resistance selection ; iii) antisense oligonucleo tides act by inactivating genes through specific interaction with a complementary DNA or RNA fragment, potentially allowing specific inhibition of selected bacterial virulence factors. However, this therapeutic class may be more suitable for viral or genetic diseases than for multidrug-resistant bacterial infections, owing to the difficulty of delivering them inside bacteria. PMID:26427289

  19. Magnetotactic bacteria and microjets: A comparative study

    NARCIS (Netherlands)

    Khalil, Islam S.M.; Magdanz, Veronika; Sanchez, Samuel; Schmidt, Oliver G.; Misra, Sarthak

    2013-01-01

    We provide a comparative study between two self-propelled microrobots, i.e., magnetotactic bacteria and microjets. This study includes characterization of their fluidic properties (linear and rotational drag coefficients) based on their morphologies and characterization of their magnetic properties

  20. Drug efflux proteins in multidrug resistant bacteria

    NARCIS (Netherlands)

    vanVeen, HW; Konings, WN

    1997-01-01

    Bacteria contain an array of transport proteins in their cytoplasmic membrane. Many of these proteins play an important role in conferring resistance to toxic compounds. The multidrug efflux systems encountered in prokaryotic cells are very similar to those observed in eukaryotic cells. Therefore, a

  1. Anchoring of proteins to lactic acid bacteria

    NARCIS (Netherlands)

    Leenhouts, K; Buist, Girbe; Kok, Jan

    1999-01-01

    The anchoring of proteins to the cell surface of lactic acid bacteria (LAB) using genetic techniques is an exciting and emerging research area that holds great promise for a wide variety of biotechnological applications. This paper reviews five different types of anchoring domains that have been exp

  2. Radiographic markers - A reservoir for bacteria?

    Energy Technology Data Exchange (ETDEWEB)

    Tugwell, Jenna, E-mail: jenna.tugwell@googlemail.co [Department of Radiology, Ysbyty Gwynedd Hospital, Bangor, North Wales (United Kingdom); Maddison, Adele [Nuffield Health, Shrewsbury Hospital (United Kingdom)

    2011-05-15

    Introduction: Amongst the most frequently handled objects in the radiology department are radiographic markers. They are personal accessories used with every patient, and are kept in the radiographers pockets when not utilised. Upon enquiry it was discovered that many radiographers disregarded the potential of these accessories to become a vector for cross-contamination thus never or rarely clean them. The aims of this study were therefore to identify if radiographic markers are a reservoir for bacteria and to establish an effective cleaning method for decontaminating them. Methodology: 25 radiographers/student radiographers were selected for this study. Swabbing of their markers prior and post cleaning took place. The microbiology laboratory subsequently analyzed the results by quantifying and identifying the bacteria present. The participants also completed a closed questionnaire regarding their markers (e.g. frequency of cleaning and type of marker) to help specify the results gained from the swabbing procedure. Results: From the sample swabbed, 92% were contaminated with various organisms including Staphylococcus and Bacillus species, the amount of bacteria present ranged from 0 to >50 CFU. There were no significant differences between disinfectant wipes and alcohol gel in decontaminating the markers. Both successfully reduced their bacterial load, with 80% of the markers post cleaning having 0 CFU. Conclusion: The results indicated that radiographic markers can become highly contaminated with various organisms thus serve as a reservoir for bacteria. In addition, the markers need to be cleaned on a regular basis, with either disinfectant wipes or alcohol gel to reduce their bacterial load.

  3. Emerging Plant Pathogenic Bacteria and Global Warming

    Science.gov (United States)

    Several bacteria, previously classified as non-fluorescent, oxidase positive pseudomonads, Ralstonia, Acidovorax, and Burkholdria have emerged as serious problems world-wide. Perhaps the most destructive is R. solanacearum (RS), a soilborne pathogen with a very wide host range. RS race 3, biovar 2...

  4. Multidrug transporters in lactic acid bacteria

    NARCIS (Netherlands)

    Mazurkiewicz, P; Sakamoto, K; Poelarends, GJ; Konings, WN

    2005-01-01

    Gram-positive lactic acid bacteria possess several Multi-Drug Resistance systems (MDRs) that excrete out of the cell a wide variety of mainly cationic lipophilic cytotoxic compounds as well as many clinically relevant antibiotics. These MDRs are either proton/drug antiporters belonging to the major

  5. DETOXIFICATION BY MAGNETOTACTIC BACTERIA IN SEDIMENTS

    Science.gov (United States)

    The ability of certain bacteria to take up iron in the environment and biosynthesis magnetic materials such as magnetite (Fe3O4) and greigite (Fe3S4) has been recognized (Blakemore, 1982; Bazylinski and Frankel, 2000). Two different mechanisms, biologically induced mineralizat...

  6. Filamentous bacteria transport electrons over centimetre distances

    DEFF Research Database (Denmark)

    Pfeffer, Christian; Larsen, Steffen; Song, Jie;

    2012-01-01

    across centimetre-wide zones. Here we present evidence that the native conductors are long, filamentous bacteria. They abounded in sediment zones with electric currents and along their length they contained strings with distinct properties in accordance with a function as electron transporters. Living...

  7. The interaction of bacteria and metal surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Mansfeld, Florian [Corrosion and Environmental Effects Laboratory (CEEL), The Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-0241 (United States)

    2007-10-10

    This review discusses different examples for the interaction of bacteria and metal surfaces based on work reported previously by various authors and work performed by the author with colleagues at other institutions and with his graduate students at CEEL. Traditionally it has been assumed that the interaction of bacteria with metal surfaces always causes increased corrosion rates ('microbiologically influenced corrosion' (MIC)). However, more recently it has been observed that many bacteria can reduce corrosion rates of different metals and alloys in many corrosive environments. For example, it has been found that certain strains of Shewanella can prevent pitting of Al 2024 in artificial seawater, tarnishing of brass and rusting of mild steel. It has been observed that corrosion started again when the biofilm was killed by adding antibiotics. The mechanism of corrosion protection seems to be different for different bacteria since it has been found that the corrosion potential E{sub corr} became more negative in the presence of Shewanella ana and algae, but more positive in the presence of Bacillus subtilis. These findings have been used in an initial study of the bacterial battery in which Shewanella oneidensis MR-1 was added to a cell containing Al 2024 and Cu in a growth medium. It was found that the power output of this cell continuously increased with time. In the microbial fuel cell (MFC) bacteria oxidize the fuel and transfer electrons directly to the anode. In initial studies EIS has been used to characterize the anode, cathode and membrane properties for different operating conditions of a MFC that contained Shewanella oneidensis MR-1. Cell voltage (V) - current density (i) curves were obtained using potentiodynamic sweeps. The current output of a MFC has been monitored for different experimental conditions. (author)

  8. The interaction of bacteria and metal surfaces

    International Nuclear Information System (INIS)

    This review discusses different examples for the interaction of bacteria and metal surfaces based on work reported previously by various authors and work performed by the author with colleagues at other institutions and with his graduate students at CEEL. Traditionally it has been assumed that the interaction of bacteria with metal surfaces always causes increased corrosion rates ('microbiologically influenced corrosion' (MIC)). However, more recently it has been observed that many bacteria can reduce corrosion rates of different metals and alloys in many corrosive environments. For example, it has been found that certain strains of Shewanella can prevent pitting of Al 2024 in artificial seawater, tarnishing of brass and rusting of mild steel. It has been observed that corrosion started again when the biofilm was killed by adding antibiotics. The mechanism of corrosion protection seems to be different for different bacteria since it has been found that the corrosion potential Ecorr became more negative in the presence of Shewanella ana and algae, but more positive in the presence of Bacillus subtilis. These findings have been used in an initial study of the bacterial battery in which Shewanella oneidensis MR-1 was added to a cell containing Al 2024 and Cu in a growth medium. It was found that the power output of this cell continuously increased with time. In the microbial fuel cell (MFC) bacteria oxidize the fuel and transfer electrons directly to the anode. In initial studies EIS has been used to characterize the anode, cathode and membrane properties for different operating conditions of a MFC that contained Shewanella oneidensis MR-1. Cell voltage (V)-current density (i) curves were obtained using potentiodynamic sweeps. The current output of a MFC has been monitored for different experimental conditions

  9. Invasion of dentinal tubules by oral bacteria.

    Science.gov (United States)

    Love, R M; Jenkinson, H F

    2002-01-01

    Bacterial invasion of dentinal tubules commonly occurs when dentin is exposed following a breach in the integrity of the overlying enamel or cementum. Bacterial products diffuse through the dentinal tubule toward the pulp and evoke inflammatory changes in the pulpo-dentin complex. These may eliminate the bacterial insult and block the route of infection. Unchecked, invasion results in pulpitis and pulp necrosis, infection of the root canal system, and periapical disease. While several hundred bacterial species are known to inhabit the oral cavity, a relatively small and select group of bacteria is involved in the invasion of dentinal tubules and subsequent infection of the root canal space. Gram-positive organisms dominate the tubule microflora in both carious and non-carious dentin. The relatively high numbers of obligate anaerobes present-such as Eubacterium spp., Propionibacterium spp., Bifidobacterium spp., Peptostreptococcus micros, and Veillonella spp.-suggest that the environment favors growth of these bacteria. Gram-negative obligate anaerobic rods, e.g., Porphyromonas spp., are less frequently recovered. Streptococci are among the most commonly identified bacteria that invade dentin. Recent evidence suggests that streptococci may recognize components present within dentinal tubules, such as collagen type I, which stimulate bacterial adhesion and intra-tubular growth. Specific interactions of other oral bacteria with invading streptococci may then facilitate the invasion of dentin by select bacterial groupings. An understanding the mechanisms involved in dentinal tubule invasion by bacteria should allow for the development of new control strategies, such as inhibitory compounds incorporated into oral health care products or dental materials, which would assist in the practice of endodontics.

  10. Segmentation of Bacteria Image Based on Level Set Method

    Institute of Scientific and Technical Information of China (English)

    WANG Hua; CHEN Chun-xiao; HU Yong-hong; YANG Wen-ge

    2008-01-01

    In biology ferment engineering, accurate statistics of the quantity of bacte-ria is one of the most important subjects. In this paper, the quantity of bacteria which was observed traditionally manuauy can be detected automatically. Image acquisition and pro-cessing system is designed to accomplish image preprocessing, image segmentation and statistics of the quantity of bacteria. Segmentation of bacteria images is successfully real-ized by means of a region-based level set method and then the quantity of bacteria is com-puted precisely, which plays an important role in optimizing the growth conditions of bac-teria.

  11. Antibacterial activity of silver-killed bacteria: the "zombies" effect

    Science.gov (United States)

    Wakshlak, Racheli Ben-Knaz; Pedahzur, Rami; Avnir, David

    2015-04-01

    We report a previously unrecognized mechanism for the prolonged action of biocidal agents, which we denote as the zombies effect: biocidally-killed bacteria are capable of killing living bacteria. The concept is demonstrated by first killing Pseudomonas aeruginosa PAO1 with silver nitrate and then challenging, with the dead bacteria, a viable culture of the same bacterium: Efficient antibacterial activity of the killed bacteria is observed. A mechanism is suggested in terms of the action of the dead bacteria as a reservoir of silver, which, due to Le-Chatelier's principle, is re-targeted to the living bacteria. Langmuirian behavior, as well as deviations from it, support the proposed mechanism.

  12. Label-Free Applications of SERS for Bacteria Analysis

    OpenAIRE

    Zhou, Haibo

    2014-01-01

    In the first part, we report on surface-enhanced Raman scattering (SERS) for living bacteria detection in drinking water by employing a synthesis of silver nanoparticles coating the cell wall of bacteria (Bacteria@AgNPs). In the second part of this thesis, we present a label-free SERS detection of bacteria on microarray at single cell level. In the third part of this thesis, we successfully counted live and dead bacteria with Bacteria@AgNPs method by SERS mapping technique.

  13. Lactic acid bacteria from fresh fruit and vegetables as biocontrol agents of phytopathogenic bacteria and fungi

    OpenAIRE

    Trias Mansilla, Rosalia; Bañeras Vives, Lluís; Montesinos Seguí, Emilio; Badosa Romañó, Esther

    2008-01-01

    This study evaluated the efficacy of lactic acid bacteria (LAB) isolated from fresh fruits and vegetables as biocontrol agents against the phytopathogenic and spoilage bacteria and fungi, Xanthomonas campestris, Erwinia carotovora, Penicillium expansum, Monilinia laxa, and Botrytis cinerea. The antagonistic activity of 496 LAB strains was tested in vitro and all tested microorganisms except P. expansum were inhibited by at least one isolate. The 496 isolates were also analyzed for the inhibit...

  14. Spray drying of dairy bacteria: New opportunities to improve the viability of bacteria powders

    OpenAIRE

    Dolivet, Anne; Mejean, Serge; Hervé, C.; Jeantet, Romain

    2013-01-01

    The most frequently used technique for dehydration of dairy bacteria is freeze drying. Of the other possible preservation techniques used in the dairy industry to produce large amounts of dairy ingredients at commercially viable processing costs, spray drying is one of the main processing tools and the cost is 10 times lower than that of freeze drying. In this work, some examples are presented for different species of dairy bacteria with respect to spray-drying processes (as an alternative ap...

  15. Observation of polyphosphate granules in cable bacteria

    Science.gov (United States)

    Yang, T.; Nielsen, L. P.; Risgaard-Petersen, N.

    2015-12-01

    Cable bacteria are long filamentous bacteria that capable for long distance electron transport: transporting electrons derived from oxidizing sulfide in anoxic layers, to oxygen at the sediment surface, over a distance of centimeters. Cable bacteria are found in many types of freshwater and marine sediment all over the world, with density of approximately thousands of kilometers per square meter. These long filaments are composed by individual cells closely related to Desulfobulbaceae, connected with a shared outer membrane inside which the strings structure are presumed to be highly conductive. The observed doubling time of cells within the filament is about 20 min, which is among the shortest compare to other bacteria. In these cable cells, we constantly observed polyphosphate granules (poly-P), regardless of cell dimension and shape. This is very interesting since it has long been recognized that the microbial polyP content is low during rapid growth and increases under unfavorable conditions, for example, increasing sulfide concentration and anoxia resulted in a decomposition of poly-P in Beggiatoa. Here, we investigated marine cable bacteria from Netherland and Aarhus Bay, focusing on the poly-P dynamics under various redox conditions. In poly-P stained cells, typically there are two big poly-P granules locate at each polar. In dividing cells, however, the morphology of poly-P changed to six small granules precisely arranged to two row. Moreover, the cells seem be able to continuously divide more than one time without elongation step. These varied poly-P morphologies demonstrate that poly-P is closely related to the cell growth and cell division, by an unknown mechanism. Individual cable filaments were picked up and were exposed to different redox conditions; our primary data indicated the cable cells could suffer anoxic condition better than oxic condition. We also detected decomposition of poly-P under anoxia. These results call for an in-depth examination

  16. Bacteria Experiment May Point Way to Slow Zika's Spread

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_158661.html Bacteria Experiment May Point Way to Slow Zika's Spread Infecting ... 4, 2016 WEDNESDAY, May 4, 2016 (HealthDay News) -- Experiments in mosquitoes suggest that bacteria may help curb ...

  17. Frequency of Resistance and Susceptible Bacteria Isolated from Houseflies

    Directory of Open Access Journals (Sweden)

    B Davari

    2010-12-01

    Conclusion: Houseflies collected from hospitals and slaughterhouse may be involved in the spread of drug resistant bacteria and may increase the potential of human exposure to drug resistant bacteria.

  18. Molecular and chemical dialogues in bacteria-protozoa interactions

    NARCIS (Netherlands)

    Song, C.; Mazzola, M.; Cheng, X.; Oetjen, J.; Alexandrov, T.; Dorrestein, P.; Watrous, J.; Voort, van der M.; Raaijmakers, J.M.

    2015-01-01

    Protozoan predation of bacteria can significantly affect soil microbial community composition and ecosystem functioning. Bacteria possess diverse defense strategies to resist or evade protozoan predation. For soil-dwelling Pseudomonas species, several secondary metabolites were proposed to provide p

  19. Interactions between Paramyxoviruses and Bacteria: Implications for Pathogenesis and Intervention

    NARCIS (Netherlands)

    D.T. Nguyen (Tien)

    2014-01-01

    markdownabstract__Abstract__ Globally, respiratory tract diseases caused by bacteria and viruses are an important burden of disease. Respiratory bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus aureus) can colonize the upper respiratory tract. The

  20. Gut Bacteria May Hold Clues to Chronic Fatigue Syndrome

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_159905.html Gut Bacteria May Hold Clues to Chronic Fatigue Syndrome Intestinal ... doctors -- may be influenced by a person's intestinal bacteria -- sometimes called gut microbiome, new research finds. "Patients ...

  1. Antibiotic-Resistant Bacteria Detected in Sewage Spill

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_160031.html Antibiotic-Resistant Bacteria Detected in Sewage Spill 'People need to be ... News) -- Sewer line breaks can release antibiotic-resistant bacteria that pose a public health threat, a new ...

  2. Oh What a Tangled Biofilm Web Bacteria Weave

    Science.gov (United States)

    ... Inside Life Science > Oh What a Tangled Biofilm Web Bacteria Weave Inside Life Science View All Articles | Inside Life Science Home Page Oh What a Tangled Biofilm Web Bacteria Weave By Elia Ben-Ari Posted May ...

  3. [RAPD analysis of plant pathogenic coryneform bacteria].

    Science.gov (United States)

    Yin, Yan-Ni; Chen, Yong-Fang; Li, Shi-Mo; Guo, Jian-Hua

    2005-12-01

    RAPD analysis was used for the taxonomy of plant pathogenic coryneform bacteria, especially for the classification of two new pathogens (Curtobacterium flaccumfaciens pv. basellae pv. nov. and Curtobacterium flaccumfaciens pv. beticola pv. nov.). 20 random primers were screened from 50 ones to detect polymorphism among the total strains used. 80.4% were polymorphic bands among the 225 ones produced. The results of pairwise similarity and UPGMA cluster analysis suggest that the two new pathovars of sugar beet (Beta vulgaris var. saccharifera) and malabar spinach (Basella rubra) are genetically close related with Curtobacterium flacumfaciens, and the minimal similarity coefficient is 0.6511. According to the RAPD analysis and previous research, some newly made taxonomic changes of the plant pathogenic coryneform bacteria are discussed. PMID:16496687

  4. Resistant bacteria in stem cell transplant recipients

    Directory of Open Access Journals (Sweden)

    Nucci Marcio

    2002-01-01

    Full Text Available Bacterial infections account for most infections in hematopoietic stem cell transplant recipients. While early mortality reduced dramatically with the introduction of the concept of empirical antibiotic therapy in neutropenic patients, no effect of prophylaxis on the mortality was observed in many studies. On the other hand, antibiotic prophylaxis has resulted in the emergence of resistance among bacteria. In addition, the choice of the antibiotic regimen for empirical therapy and the practices of antibiotic therapy during neutropenia may result in a significant shift in the pattern of bacterial infections. The use of quinolones and vancomycin as prophylaxis, and of carbapenems and vancomycin in the empirical antibiotic therapy, are associated with the appearance of resistant Gram-positive and Gram-negative bacteria. Therefore, hematologists must be aware of the impact of these practices on the emergence of infections due to multi-resistant pathogens, since these infections may be associated with increased mortality.

  5. Quorum sensing in plant-pathogenic bacteria.

    Science.gov (United States)

    Von Bodman, Susanne B; Bauer, W Dietz; Coplin, David L

    2003-01-01

    Quorum sensing (QS) allows bacteria to assess their local population density and/or physical confinement via the secretion and detection of small, diffusible signal molecules. This review describes how phytopathogenic bacteria have incorporated QS mechanisms into complex regulatory cascades that control genes for pathogenicity and colonization of host surfaces. Traits regulated by QS include the production of extracellular polysaccharides, degradative enzymes, antibiotics, siderophores, and pigments, as well as Hrp protein secretion, Ti plasmid transfer, motility, biofilm formation, and epiphytic fitness. Since QS regulatory systems are often required for pathogenesis, interference with QS signaling may offer a means of controlling bacterial diseases of plants. Several bacterial pathogens of plants that have been intensively studied and have revealed information of both fundamental and practical importance are reviewed here: Agrobacterium tumefaciens, Pantoea stewartii, Erwinia carotovora, Ralstonia solanacearum, Pseudomonas syringae, Pseudomonas aeruginosa, and Xanthomonas campestris. PMID:12730390

  6. Sulfate inhibition effect on sulfate reducing bacteria

    Directory of Open Access Journals (Sweden)

    Sulaiman Al Zuhair

    2008-12-01

    Full Text Available There is an increasing interest in the potential of bacterial sulfate reduction as an alternative method for sulfate removal from wastewater. Under anaerobic conditions, sulfate-reducing bacteria (SRB utilize sulfate to oxidize organic compounds and generate sulfide (S2-. SRB were successfully isolated from sludge samples obtained from a local petroleum refinery, and used for sulfate removal. The effects of initial sulfate concentration, temperature and pH on the rate of bacterial growth and anaerobic sulfate removal were investigated and the optimum conditions were identified. The experimental data were used to determine the parameters of two proposed kinetic model, which take into consideration substrate inhibition effect. Keywords: Sulfate Reducing Bacteria, Sulfate, Kinetic Model, Biotreatement, Inhibition Received: 31 August 2008 / Received in revised form: 18 September 2008, Accepted: 18 September 2008 Published online: 28 September 2008

  7. Sulfur-oxidizing bacteria in environmental technology.

    Science.gov (United States)

    Pokorna, Dana; Zabranska, Jana

    2015-11-01

    Hydrogen sulfide is widely known as the most undesirable component of biogas that caused not only serious sensoric and toxic problems, but also corrosion of concrete and steel structures. Many agricultural and industrial waste used in biogas production, may contain a large amount of substances that serve as direct precursors to the formation of sulfide sulfur-sources of hydrogen sulfide in the biogas. Biological desulfurization methods are currently promoted to abiotic methods because they are less expensive and do not produce undesirable materials which must be disposed of. The final products of oxidation of sulfides are no longer hazardous. Biological removal of sulfide from a liquid or gaseous phase is based on the activity of sulfur-oxidizing bacteria. They need an oxidizing agent such as an acceptor of electrons released during the oxidation of sulfides-atmospheric oxygen or oxidized forms of nitrogen. Different genera of sulfur-oxidizing bacteria and their technological application are discussed.

  8. Bacteria, some permanent tenants Space Station

    International Nuclear Information System (INIS)

    Vacuum cleaners to operate the vacuum or rags with ethanol they are the products of cleaning of the astronauts. Is there tight spaces fully sterilized? It seems not, even in the Space Station International (ISS). When it comes to bacteria, they are able to travel more than 400 kilometers housed in costumes, bodies and interior of the astronauts themselves and settle in a enclosed space where-unlike in a cleanroom 'terrestre- the air is not recycled. A NASA study has found an abundance of bacteria 'opportunists' which, although harmless on Earth, they might derivasen cause infections in inflammations or skin irritations. Not forgetting those fungi that could damage or affect the infrastructure equipment space. (Author)

  9. HERBASPIRILLUM-LIKE BACTERIA IN BANANA PLANTS

    Directory of Open Access Journals (Sweden)

    Weber Olmar B.

    2001-01-01

    Full Text Available Diazotrophic bacteria isolated from banana plants were characterized by morphological and physiological aspects. Three different groups of these plant-bacteria could be established. Two of them showed similarity to species of the Herbaspirillum genus. The third one was different because used only a few carbon substrates and produced water diffusible compounds that fluoresced under UV light. All three bacterial groups were thin rods with mono or bipolar flagella, presented negative reaction in Gram stain, showed catalase activity, were able to reduce nitrate and grew better in semi-solid JNFb medium at 31ºC. The nitrogenase activity was detected in semi-solid N-free JNFb medium and expressed higher values when pH ranged from 6.5 to 7.0 (groups I and II and 6.0 to 6.5 (group III. The diazotrophs isolated from banana plants were distinct from species of Herbaspirillum previously identified in gramineous plants.

  10. Ancient bacteria show evidence of DNA repair

    DEFF Research Database (Denmark)

    Johnson, Sarah Stewart; Hebsgaard, Martin B; Christensen, Torben R;

    2007-01-01

    Recent claims of cultivable ancient bacteria within sealed environments highlight our limited understanding of the mechanisms behind long-term cell survival. It remains unclear how dormancy, a favored explanation for extended cellular persistence, can cope with spontaneous genomic decay over...... geological timescales. There has been no direct evidence in ancient microbes for the most likely mechanism, active DNA repair, or for the metabolic activity necessary to sustain it. In this paper, we couple PCR and enzymatic treatment of DNA with direct respiration measurements to investigate long...... that this long-term survival is closely tied to cellular metabolic activity and DNA repair that over time proves to be superior to dormancy as a mechanism in sustaining bacteria viability....

  11. ANTIMICROBIAL ACTIVITY OF MEDICINAL PLANTS AGAINST DIFFERENT STRAINS OF BACTERIA

    OpenAIRE

    Alexander Vatľák; Adriana Kolesárová; Nenad Vukovič; Katarína Rovná; Jana Petrová; Viktória Vimmerová; Lukáš Hleba; Martin Mellen; Miroslava Kačániová

    2014-01-01

    In this study, methanolic extracts of Tilia cordata Mill. and Aesculus hippocastanum which had been described in herbal books, were screened for their antimicrobial activity against gramnegative and grampositive bacteria. The following strains of bacteria for antimicrobial activity were used gramnegative bacteria: Escherichia coli CCM 3988, Listeria ivanovii CCM 5884, Listeria innocua CCM 4030, Pseudomonas aeruginosa CCM 1960, Serratia rubidaea CCM 4684 and grampositive bacteria: Brochothrix ...

  12. Phylogenetic analysis and development of probes for differentiating methylotrophic bacteria.

    OpenAIRE

    Brusseau, G A; Bulygina, E S; Hanson, R S

    1994-01-01

    Fifteen small-subunit rRNAs from methylotrophic bacteria have been sequenced. Comparisons of these sequences with 22 previously published sequences further defined the phylogenetic relationships among these bacteria and illustrated the agreement between phylogeny and physiological characteristics of the bacteria. Phylogenetic trees were constructed with 16S rRNA sequences from methylotrophic bacteria and representative organisms from subdivisions within the class Proteobacteria on the basis o...

  13. Control of Fusarium Wilt of Chili With Chitinolytic Bacteria

    OpenAIRE

    DWI SURYANTO; SITI PATONAH; ERMAN MUNIR

    2010-01-01

    Biological control of plant disease using antagonistic microorganism has been obtaining much attention and implemented for decades. One of the potential microorganisms used in this strategy is chitinolytic bacteria. Utilization of this bacteria ranges from cell life, enzymes, genes, or other metabolites. In this study, we examined the ability of chitinolytic bacteria as a biocontrol agent of Fusarium wilt of red chili (Capsicum annuum L.) seedlings. The ability of chitinolytic bacteria to sup...

  14. Hydrocarbonoclastic bacteria: from bioremediation to bioenergy feedstock

    OpenAIRE

    Carvalho, Ana Rita Castro

    2015-01-01

    Tese de Doutoramento em Engenharia Química e Biológica. Bacterial storage lipids are being considered as viable alternative feedstocks for industrial and biotechnological applications, compared to conventional ones. The production of these bacterial compounds can be obtained from different carbon sources, including inexpensive and recalcitrant wastes. This thesis explores the potential of using hydrocarbonoclastic bacteria to obtain lipid reserve substances from hydrocarbon-based wastes, p...

  15. Metabolic Flexibility of Sulfate-Reducing Bacteria

    OpenAIRE

    Plugge, Caroline M.; Zhang, Weiwen; Scholten, Johannes C. M.; Stams, Alfons J. M.

    2011-01-01

    Dissimilatory sulfate-reducing prokaryotes (SRB) are a very diverse group of anaerobic bacteria that are omnipresent in nature and play an imperative role in the global cycling of carbon and sulfur. In anoxic marine sediments sulfate reduction accounts for up to 50% of the entire organic mineralization in coastal and shelf ecosystems where sulfate diffuses several meters deep into the sediment. As a consequence, SRB would be expected in the sulfate-containing upper sediment layers, whereas me...

  16. [Genetic virulence markers of opportunistic bacteria].

    Science.gov (United States)

    Bondarenko, V M

    2011-01-01

    The analysis of opportunistic bacteria phenotypic and genetic virulence markers indicates that pathogenicity formation is based on a structural modification of bacterial DNA which is linked with migration of interbacterial pathogenicity "islands" genetic determinants. Structural organization features of these mobile genetic elements determine high expression probability, and PCR detection of pathogenicity "islands" determinants that control adhesins, invasins, cytotoxic and cytolitic toxines synthesis may indicate etiopathogenetic significance of clinical isolates.

  17. Tumour targeting with systemically administered bacteria.

    LENUS (Irish Health Repository)

    Morrissey, David

    2012-01-31

    Challenges for oncology practitioners and researchers include specific treatment and detection of tumours. The ideal anti-cancer therapy would selectively eradicate tumour cells, whilst minimising side effects to normal tissue. Bacteria have emerged as biological gene vectors with natural tumour specificity, capable of homing to tumours and replicating locally to high levels when systemically administered. This property enables targeting of both the primary tumour and secondary metastases. In the case of invasive pathogenic species, this targeting strategy can be used to deliver genes intracellularly for tumour cell expression, while non-invasive species transformed with plasmids suitable for bacterial expression of heterologous genes can secrete therapeutic proteins locally within the tumour environment (cell therapy approach). Many bacterial genera have been demonstrated to localise to and replicate to high levels within tumour tissue when intravenously (IV) administered in rodent models and reporter gene tagging of bacteria has permitted real-time visualisation of this phenomenon. Live imaging of tumour colonising bacteria also presents diagnostic potential for this approach. The nature of tumour selective bacterial colonisation appears to be tumour origin- and bacterial species- independent. While originally a correlation was drawn between anaerobic bacterial colonisation and the hypoxic nature of solid tumours, it is recently becoming apparent that other elements of the unique microenvironment within solid tumours, including aberrant neovasculature and local immune suppression, may be responsible. Here, we consider the pre-clinical data supporting the use of bacteria as a tumour-targeting tool, recent advances in the area, and future work required to develop it into a beneficial clinical tool.

  18. Bioactive Compounds from Marine Bacteria and Fungi

    OpenAIRE

    Debbab, Abdessamad; Aly, Amal H.; Lin, Wen H.; Proksch, Peter

    2010-01-01

    Summary Marine bacteria and fungi are of considerable importance as new promising sources of a huge number of biologically active products. Some of these marine species live in a stressful habitat, under cold, lightless and high pressure conditions. Surprisingly, a large number of species with high diversity survive under such conditions and produce fascinating and structurally complex natural products. Up till now, only a small number of microorganisms have been investigated for bioactive me...

  19. Study of fatty acid-bacteria interactions

    International Nuclear Information System (INIS)

    Complete text of publication follows. During our work we investigated fatty acid-bacteria interactions. The antibacterial property of fatty acids was reported by several authors. Despite of them there is not reassuring explanation about the mechanism of the antibacterial activity of these compounds. An effect can considerably change in case of different structured fatty acids. Our earlier studies conduct that small changes in the structures can modify changes in their behavior towards bacteria. The stearic acid does not cause any antibacterial effects during the first few hours of the investigation, may even help the bacterial growth. However, linolic acid (C18:2) shows a strong antibacterial effect during the first hours. After 24 hours this effect wears out and the bacteria have adapted to the stress. We studied the antibacterial activity using direct bioautography. This method has the advantage to allow examining lipophilic compounds. The linoleic acid decomposes in time under different physiological conditions creating numerous oxidized molecules. This may be the reason of its antimicrobial effect. For studying this phenomenon we used infrared and mass spectroscopic methods. We applied infrared spectroscopy for indicating any changes in the spectra of the fatty acids after the interaction of fatty acids with bacteria. So we are able to deduct on what could happen during these process. We paid great attention towards the changes of double bonds, on methylation and demethylation processes. Using mass spectroscopy we searched for oxidized products that may play important role in this process. These studies are only part of our more widespreading investigations, dealing with the antimicrobial properties of fatty acids.

  20. Plague Bacteria Target Immune Cells During Infection

    OpenAIRE

    Marketon, Melanie M.; DePaolo, R. William; DeBord, Kristin L.; Jabri, Bana; Schneewind, Olaf

    2005-01-01

    The plague is caused by the bacterium Yersinia pestis. Plague bacteria are thought to inject effector Yop proteins into host cells via the type III pathway. The identity of the host cells targeted for injection during plague infection is unknown. We found, using Yop β-lactamase hybrids and fluorescent staining of live cells from plague-infected animals, that Y. pestis selected immune cells for injection. In vivo, dendritic cells, macrophages, and neutrophils were injected most frequently, whe...

  1. Bacterial biofilms. Bacteria Quorum sensing in biofilms

    OpenAIRE

    E. S. Vorobey; O. S. Voronkova; A. I. Vinnikov

    2012-01-01

    Data on biofilms, their structure and properties, peculiarities of formation and interaction between microorganisms in the film are presented. Information on discovery and study of biofilms, importance of biofilms in the medical and clinical microbiology are offered. The data allow to interpret biofilm as a form of existence of human normal microflora. For the exchange of information within the biofilm between the individual cells of the same or different species bacteria use the signal molec...

  2. Seeing Streptococcus pneumoniae, a Common Killer Bacteria

    DEFF Research Database (Denmark)

    Kjærgaard, Rikke Schmidt; Andersen, Ebbe Sloth

    2014-01-01

    Look around you. The diversity and complexity of life on earth is overwhelming and data continues to grow. In our desire to understand and explain everything scientifically from molecular evolution to supernovas we depend on visual representations. This paper investigates visual representations o......-assisted representations can add to our scientific knowledge about this dangerous bacteria. Is there still a role for the scientific illustrator in the scientific process and synthesis of scientific knowledge?...

  3. Bacteria Foraging Algorithm in Antenna Design

    OpenAIRE

    Biswa Binayak Mangaraj; Manas Ranjan Jena; Saumendra Kumar Mohanty

    2016-01-01

    A simple design procedure to realize an optimum antenna using bacteria foraging algorithm (BFA) is proposed in this paper. The first antenna considered is imaginary. This antenna is optimized using the BFA along with a suitable fitness function formulated by considering some performance parameters and their best values. To justify the optimum design approach, one 12-element Yagi-Uda antenna is considered for an experiment. The optimized result of this antenna obtained using the optimization a...

  4. Cellulose biosynthesis and function in bacteria.

    OpenAIRE

    Ross, P; Mayer, R; Benziman, M

    1991-01-01

    The current model of cellulose biogenesis in plants, as well as bacteria, holds that the membranous cellulose synthase complex polymerizes glucose moieties from UDP-Glc into beta-1,4-glucan chains which give rise to rigid crystalline fibrils upon extrusion at the outer surface of the cell. The distinct arrangement and degree of association of the polymerizing enzyme units presumably govern extracellular chain assembly in addition to the pattern and width of cellulose fibril deposition. Most e...

  5. Macrophage defense mechanisms against intracellular bacteria.

    Science.gov (United States)

    Weiss, Günter; Schaible, Ulrich E

    2015-03-01

    Macrophages and neutrophils play a decisive role in host responses to intracellular bacteria including the agent of tuberculosis (TB), Mycobacterium tuberculosis as they represent the forefront of innate immune defense against bacterial invaders. At the same time, these phagocytes are also primary targets of intracellular bacteria to be abused as host cells. Their efficacy to contain and eliminate intracellular M. tuberculosis decides whether a patient initially becomes infected or not. However, when the infection becomes chronic or even latent (as in the case of TB) despite development of specific immune activation, phagocytes have also important effector functions. Macrophages have evolved a myriad of defense strategies to combat infection with intracellular bacteria such as M. tuberculosis. These include induction of toxic anti-microbial effectors such as nitric oxide and reactive oxygen intermediates, the stimulation of microbe intoxication mechanisms via acidification or metal accumulation in the phagolysosome, the restriction of the microbe's access to essential nutrients such as iron, fatty acids, or amino acids, the production of anti-microbial peptides and cytokines, along with induction of autophagy and efferocytosis to eliminate the pathogen. On the other hand, M. tuberculosis, as a prime example of a well-adapted facultative intracellular bacterium, has learned during evolution to counter-balance the host's immune defense strategies to secure survival or multiplication within this otherwise hostile environment. This review provides an overview of innate immune defense of macrophages directed against intracellular bacteria with a focus on M. tuberculosis. Gaining more insights and knowledge into this complex network of host-pathogen interaction will identify novel target sites of intervention to successfully clear infection at a time of rapidly emerging multi-resistance of M. tuberculosis against conventional antibiotics. PMID:25703560

  6. Bioleaching of marmatite using moderately thermophilic bacteria

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hong-bo; LIU Fei-fei; ZOU Ying-qin; ZENG Xiao-xi; QIU Guan-zhou

    2008-01-01

    The process of bioleaching marmatite using moderately thermophilic bacteria was studied by comparing marmatite leaching performance of mesophiles and moderate thermophiles and valuating the effect of venting capacity as well as pulp density on marmatite leaching performance of moderate thermophiles. The results show that moderate thermophiles have more advantages over mesophilies in bioleaching marmatite at 45℃ and the pulp density of 50g/L, and the zinc extraction efficiency reaches 93.1% in 20d. Aeration agitation can improve the transfer of O2 and CO2 in solution and promote the growth of bacteria and therefore, enhance the leaching efficiency. Under the venting levels of 50, 200 and 800mL/min, the zinc extraction efficiencies by moderate thermophiles are 57.8%, 92.5% and 96.0%, respectively. With the increase of pulp density, the total leaching amount of valuable metals increases, however, the extraction efficiency decreases due to many reasons, such as increasing shear force leading to poorly growth condition for bacteria, etc. The zinc extraction decreases remarkably to 58.9% while the pulp density mounts up 20%.

  7. Predominant bacteria diversity in Chinese traditional sourdough.

    Science.gov (United States)

    Zhang, Guohua; He, Guoqing

    2013-08-01

    The purpose of this study was to identify the major bacteria in Chinese traditional sourdough (CTS). Five CTS samples (Hn-87, Sx-91, Gs-107, Hf-112, and Hr-122) were collected from different Chinese steamed breads shops or private households. The total bacterial DNA was extracted from sourdough samples and sequenced using Illumina Hiseq 2000 system. Illumina tags were assigned to BLASTN server based on 16S rRNA libraries to reveal a genetic profile. Phylogenetic analysis revealed that the bacteria in traditional sourdough samples were dominated by the genera Leuconostoc and Lactobacillus. Beta diversity analysis, principal component analysis, and cluster analysis compared the bacterial differences in traditional sourdough samples. The results showed that Leuconostoc, Lactobacillus, and Weissella were the predominant genera among the 5 samples. This differentiated the sourdoughs into 3 typologies, namely, 1) Gs-107 and Sx-91, 2) Hr-122 and Hn-87, and 3) Hf-112. This study identified 3 unique major bacteria genus in CTS bread ecosystems.

  8. Transfer of DNA from Bacteria to Eukaryotes

    Directory of Open Access Journals (Sweden)

    Benoît Lacroix

    2016-07-01

    Full Text Available Historically, the members of the Agrobacterium genus have been considered the only bacterial species naturally able to transfer and integrate DNA into the genomes of their eukaryotic hosts. Yet, increasing evidence suggests that this ability to genetically transform eukaryotic host cells might be more widespread in the bacterial world. Indeed, analyses of accumulating genomic data reveal cases of horizontal gene transfer from bacteria to eukaryotes and suggest that it represents a significant force in adaptive evolution of eukaryotic species. Specifically, recent reports indicate that bacteria other than Agrobacterium, such as Bartonella henselae (a zoonotic pathogen, Rhizobium etli (a plant-symbiotic bacterium related to Agrobacterium, or even Escherichia coli, have the ability to genetically transform their host cells under laboratory conditions. This DNA transfer relies on type IV secretion systems (T4SSs, the molecular machines that transport macromolecules during conjugative plasmid transfer and also during transport of proteins and/or DNA to the eukaryotic recipient cells. In this review article, we explore the extent of possible transfer of genetic information from bacteria to eukaryotic cells as well as the evolutionary implications and potential applications of this transfer.

  9. Anhydrobiosis in bacteria: From physiology to applications

    Indian Academy of Sciences (India)

    Armando Hernández García

    2011-12-01

    Anhydrobiosis is a phenomenon related to the partial or total desiccation of living organisms, keeping their vital functions after rehydration. The desiccated state in prokaryotes has been widely studied, mainly due to the broad spectrum of the anhydrobiosis applications. In this review, we present the basic theoretical concepts related to anhydrobiosis, focusing on bacterial species. An update about desiccation tolerance in bacteria is given; and the general mechanisms of desiccation tolerance and desiccation damage are described. In addition, we show how the study of anhydrobiosis in prokaryotes has established the theoretical and practical basis for the development of the drying technologies. With regard to the desiccation tolerance in bacteria, although many mechanisms remain undiscovered at the molecular level, important research about the physiology of the anhydrobiotic state and its applications has been performed, and here we provide the most recent information about this subject. On the other hand, the most widely used drying technologies and their particular applications in several fields are described (e.g. medicine, agriculture and food industry). Finally, topics on the stability of desiccated bacterial cells are treated, concluding with the necessity of focusing the research on the mathematical modelling of the desiccated state in bacteria.

  10. Engineering Hybrid Chemotaxis Receptors in Bacteria.

    Science.gov (United States)

    Bi, Shuangyu; Pollard, Abiola M; Yang, Yiling; Jin, Fan; Sourjik, Victor

    2016-09-16

    Most bacteria use transmembrane sensors to detect a wide range of environmental stimuli. A large class of such sensors are the chemotaxis receptors used by motile bacteria to follow environmental chemical gradients. In Escherichia coli, chemotaxis receptors are known to mediate highly sensitive responses to ligands, making them potentially useful for biosensory applications. However, with only four ligand-binding chemotaxis receptors, the natural ligand spectrum of E. coli is limited. The design of novel chemoreceptors to extend the sensing capabilities of E. coli is therefore a critical aspect of chemotaxis-based biosensor development. One path for novel sensor design is to harvest the large natural diversity of chemosensory functions found in bacteria by creating hybrids that have the signaling domain from E. coli chemotaxis receptors and sensory domains from other species. In this work, we demonstrate that the E. coli receptor Tar can be successfully combined with most typical sensory domains found in chemotaxis receptors and in evolutionary-related two-component histidine kinases. We show that such functional hybrids can be generated using several different fusion points. Our work further illustrates how hybrid receptors could be used to quantitatively characterize ligand specificity of chemotaxis receptors and histidine kinases using standardized assays in E. coli.

  11. Bacteria as transporters of phosphorus through soil

    DEFF Research Database (Denmark)

    Glæsner, N.; Bælum, Jacob; Jacobsen, C. S.;

    2016-01-01

    The transport of phosphorus (P) from agricultural land has led to the eutrophication of surface waters worldwide, especially in areas with intensive animal production. In this research, we investigated the role of bacteria in the leaching of P through three agricultural soils with different......RNA genes cell−1. Leaching of bacteria was in the range of 2.5–4.5 × 105 cells ml−1 prior to application of slurry to the three soil textures. After slurry application, leaching increased to 1.1 × 106 cells ml−1 in the loamy sand, 4.9 × 106 cells ml−1 in the sandy loam and 5.0 × 106 cells ml−1 in the loam....... Based on the reported P content of soil bacteria, 0.3–1.8% of the total P leached was present in the bacterial biomass when no slurry was applied, whereas slurry application increased the leaching of P from the bacterial biomass to 3−7.9% of total P leached. Bacterial leaching was related...

  12. Soil bacteria for remediation of polluted soils

    Energy Technology Data Exchange (ETDEWEB)

    Springael, D.; Bastiaens, L.; Carpels, M.; Mergaey, M.; Diels, L.

    1996-09-18

    Soil bacteria, specifically adapted to contaminated soils, may be used for the remediation of polluted soils. The Flemish research institute VITO has established a collection of bacteria, which were isolated from contaminated areas. This collection includes microbacteria degrading mineral oils (Pseudomonas sp., Acinetobacter sp. and others), microbacteria degrading polycyclic aromatic hydrocarbons (genera Sphingomonas and Mycobacterium), microbacteria degrading polychlorobiphenyls (genus Ralstonia and strains related to beta-Proteobacteria), and metal resistant bacteria with plasmid borne resistances to Cd, Zn, Ni, Co, Cu, Hg, and Cr. Bench-scale reactors were developed to investigate the industrial feasibility of bioremediation. Batch Stirred Tank Reactors were used to evaluate the efficiency of oil degraders. Soils, contaminated with non-ferrous metals, were treated using a Bacterial Metal Slurry Reactor. It was found that the reduction of the Cd concentration may vary strongly from sample to sample: reduction factors vary from 95 to 50%. Is was shown that Cd contained in metallic sinter and biologically unavailable Cd could not be removed.

  13. The growth of bacteria on organic compounds in drinking water

    NARCIS (Netherlands)

    Kooy, van der D.

    1984-01-01

    Growth ("regrowth") of bacteria In drinking water distribution systems results in a deterioration of the water quality. Regrowth of chemoheterotrophic bacteria depends on the presence of organic. compounds that serve as a nutrient source for these bacteria. A batch-culture technique was developed to

  14. Metabolism in bacteria at low temperature: A recent report

    Indian Academy of Sciences (India)

    Dipanwita Sengupta; Madhab K Chattopadhyay

    2013-06-01

    The adaptability of bacteria to extreme cold environments has been demonstrated from time to time by various investigators. Metabolic activity of bacteria at subzero temperatures is also evidenced. Recent studies indicate that bacteria continue both catabolic and anabolic activities at subzero temperatures. Implications of these findings are discussed.

  15. Quantification and Qualification of Bacteria Trapped in Chewed Gum

    NARCIS (Netherlands)

    Wessel, Stefan W.; van der Mei, Henny C.; Morando, David; Slomp, Anje M.; van de Belt-Gritter, Betsy; Maitra, Amarnath; Busscher, Henk J.

    2015-01-01

    Chewing of gum contributes to the maintenance of oral health. Many oral diseases, including caries and periodontal disease, are caused by bacteria. However, it is unknown whether chewing of gum can remove bacteria from the oral cavity. Here, we hypothesize that chewing of gum can trap bacteria and r

  16. IDENTIFICATION OF INDUSTRIALLY IMPORTANT LACTIC ACID BACTERIA IN FOODSTUFFS

    OpenAIRE

    Prosekov, A.; Babich, O.; Bespomestnykh, K.

    2013-01-01

    Universal genus-specific primers for comparative analysis of two aligned 16S rRNA gene nucleotide sequences of lactic acid bacteria were constructed. The method to identify lactic acid bacteria and a comprehensive plan for their genus and species identification may be used to characterize isolated strains of the Lactobacillus genus bacteria and in quality control of foodstuffs enriched with Lactobacillus.

  17. Mucolytic bacteria with increased prevalence in IBD mucosa augment in vitro utilization of mucin by other bacteria

    NARCIS (Netherlands)

    Png, C.W.; Linden, S.K.; Gilshenan, K.S.; Zoetendal, E.G.; McSweeney, C.S.; Sly, L.I.; McGuckin, M.A.; Florin, T.H.

    2010-01-01

    OBJECTIVES: Mucosa-associated bacteria are increased in inflammatory bowel disease (IBD), which suggests the possibility of an increased source of digestible endogenous mucus substrate. We hypothesized that mucolytic bacteria are increased in IBD, providing increased substrate to sustain nonmucolyti

  18. The analysis of bacteria strains and sensitivity of bacteria to antibiotics in acute obstructive cholangitis with suppuration

    Institute of Scientific and Technical Information of China (English)

    顾彬

    2013-01-01

    Objective To analyze the changes of bacteria stains in acute obstructive cholangitis with suppuration(AOSC) and sensitivity of different bacteria strains to antibiotics in recent decade. Methods The data of bacterial

  19. Diagnóstico precoz de la neumonía asociada al ventilador. Evaluación seriada de biomarcadores en minilavado broncoalveolar y monitorización microbiológica, complementado con condensado de aire exhalado y sangre.

    OpenAIRE

    Borrás Pallé, Santiago

    2015-01-01

    La Neumonía asociada a ventilación mecánica (NAV) es un tipo de neumonía nosocomial que se desarrolla tras más de 48 horas de VM, siendo una complicación frecuente y grave cuyo pronóstico se ensombrece por un diagnóstico y tratamiento tardío. Desgraciadamente, con las herramientas actuales no siempre es posible llegar a un diagnóstico correcto y definitivo. El desarrollo de la misma es un proceso dinámico y dado que debe existir una respuesta inflamatoria precoz ante la infección, inicia...

  20. Evaluación de la eficacia y seguridad de una pauta flexible, guiada por tomografía de coherencia óptica (OCT), de ranibizumab (Lucentis®) en el tratamiento de la degeneración macular asociada a la edad (DMAE) exudativa

    OpenAIRE

    Reche Frutos, Juan

    2012-01-01

    Los estudios pivotales de ranibizumab en el tratamiento de la Degeneración Macular Asociada a la Edad (DMAE) exudativa, conocidos por los acrónimos MARINA y ANCHOR, demostraron que la administración mensual de ranibizumab conseguía mejorar la agudeza visual media de los pacientes. Para tratar de reducir los riesgos asociados al tratamiento continuado, reducir el coste económico y evitar la inyección cuando la lesión está inactiva se han realizado varios ensayos clínicos con diversas pautas...

  1. Bacteria-Targeting Nanoparticles for Managing Infections

    Science.gov (United States)

    Radovic-Moreno, Aleksandar Filip

    Bacterial infections continue to be a significant concern particularly in healthcare settings and in the developing world. Current challenges include the increasing spread of drug resistant (DR) organisms, the side effects of antibiotic therapy, the negative consequences of clearing the commensal bacterial flora, and difficulties in developing prophylactic vaccines. This thesis was an investigation of the potential of a class of polymeric nanoparticles (NP) to contribute to the management of bacterial infections. More specifically, steps were taken towards using these NPs (1) to achieve greater spatiotemporal control over drug therapy by more targeted antibiotic delivery to bacteria, and (2) to develop a prophylactic vaccine formulation against the common bacterial sexually transmitted disease (STD) caused by Chlamydia trachomatis. In the first part, we synthesized polymeric NPs containing poly(lactic-co-glycolic acid)-block-poly(L-histidine)-block-poly(ethylene glycol) (PLGA-PLH-PEG). We show that these NPs are able to bind to bacteria under model acidic infection conditions and are able to encapsulate and deliver vancomycin to inhibit the growth of Staphylococcus aureus bacteria in vitro. Further work showed that the PLGA-PLH-PEG-based NPs demonstrated the potential for competition for binding bacteria at a site of infection from soluble protein and model phagocytic and tissue-resident cells in a NP composition dependent manner. The NPs demonstrated low toxicity in vitro, were well tolerated by mice in vivo, and circulated in the blood on timescales comparable to control PLGA-PEG NPs. In the second part, we used PLGA-PLH-PEG-based NPs to design a prophylactic vaccine against the obligate intracellular bacterium Chlamydia trachomatis, the most common cause of bacterial STD in the world. Currently, no vaccines against this pathogen are approved for use in humans. We first formulated NPs encapsulating the TLR7 agonist R848 conjugated to poly(lactic acid) (R848-PLA

  2. La proteína asociada a SLAM (SAP regula la expresión de IFN-g en lepra The SLAM-associated protein (SAP regulates IFN-g expression in leprosy

    Directory of Open Access Journals (Sweden)

    María F. Quiroga

    2004-10-01

    Full Text Available La inmunidad protectora contra Mycobacterium leprae requiere IFN-g. Los pacientes con lepra tuberculoide producen localmente citoquinas Th1, mientras que los pacientes lepromatosos producen citoquinas Th2. La molécula linfocitaria activadora de señales (SLAM y la proteína asociada a SLAM (SAP participan en la diferenciación celular que conduce a producción de patrones específicos de citoquinas. A fin de investigar la vía SLAM/SAP en la infección por M. leprae, determinamos expresión de ARN mensajero (ARNm de SAP, IFN-g y SLAM en pacientes con lepra. Observamos que la expresión de SLAM correlacionó en forma directa con la expresión de IFN-g, mientras que la expresión de SAP correlacionó inversamente con la expresión de ambas proteínas. Así, nuestros resultados indican que SAP interferiría con las respuestas de citoquinas Th1 mientras que SLAM contribuiría con la respuesta Th1 en lepra, señalando a la vía SLAM/SAP como potencial blanco modulador de citoquinas en enfermedades con respuestas Th2 disfuncionales.Tuberculoid leprosy patients locally produce Th1 cytokines, while lepromatous patients produce Th2 cytokines. Signaling lymphocytic activation molecule (SLAM and the SLAM-associated protein (SAP participate in the differentiation process that leads to the production of specific patterns of cytokines by activated T cells. To investigate the SLAM/SAP pathway in M. leprae infection, we determined the expression of SAP, IFN-g and SLAM RNA messenger in leprosy patients. We found a direct correlation of SLAM expression with IFN-g expression, whereas the expression of SAP was inversely correlated with the expression of both SLAM and IFN-g. Therefore, our data indicate that SAP might interfere with Th1 cytokine responses while SLAM expression may contribute to Th1 responses in leprosy. This study further suggests that the SLAM/SAP pathway might be a focal point for therapeutic modulation of T cell cytokine responses in diseases

  3. COMPOSICIÓN QUIMICA DE LA LECHE, DIGESTIBILIDAD in vitro DE LA MATERIA SECA Y PRODUCCIÓN EN VACAS ALIMENTADAS CON GRAMÍNEAS SOLAS O ASOCIADAS CON Lotus uliginosus

    Directory of Open Access Journals (Sweden)

    A. Morales

    2013-01-01

    Full Text Available La presente investigación tuvo como objetivo evaluar el uso de la leguminosa Lotus uliginosus como alternativa de inclusión dentro de las praderas en dos ecorregiones estratégicas de la sabana de Bogotá. en cada finca se evaluaron cuatro tratamientos: 1 kikuyo solo (P. clandestinum, 2 kikuyo asociado con trébol pata de pájaro ( P.clandes-tinum + L. uliginosus, 3 festuca alta sola (F. arundinacea y 4 Festuca alta asociada con trébol pata de pájaro (F. arundinacea + L. uliginosus. el número de bovinos varió de acuerdo a la capacidad de carga de cada finca. se utilizaron animales que se encontraban en el segundo tercio de lactancia durante un período experimental de siete días. en cada tratamiento se determinó la producción (L/día y calidad de leche (% de grasa, proteína y sólidos totales; en la pastura se evaluó la composición química (Ms, Fdn, Fda y la digestibilidad in vitro de la materia seca (divMs. se midió el consumo voluntario. en la finca Megaleche la producción de biomasa presentó diferencias significativas (P<0,05 entre los tratamientos destacándose el tratamiento del kikuyo solo; la calidad nutricional de las pasturas también presentó diferencias (P<0,04 destacándose el tratamiento de kikuyo + trébol pata de pájaro, asociación que también se destacó en consumo voluntario (P< 0.05 y producción de leche (P<0,05. en la finca Colega el contenido de proteína del forraje presentó diferencias cuando las gramíneas se asociaron con el trébol pata de pájaro (P<0,001. se concluyó que la introducción del Lotus en las praderas mejoró la producción de leche y consumo de materia seca en los animales.

  4. Patología cerebro-vascular hemorrágica en adultos asociada al consumo de cocaína Cerebral haemorrhage in adults associated with the use of cocaine

    Directory of Open Access Journals (Sweden)

    M. Blanco

    2005-07-01

    Full Text Available La cocaína es la segunda droga de comercio ilegal más consumida en España después del cannabis. El número de pacientes atendidos en los servicios de urgencias tras consumir cocaína y los casos de muerte secundarios al consumo de la misma han ido aumentando hasta multiplicarse por seis en los últimos años. El consumo de este alcaloide ocasiona efectos nocivos, constatados sobre diferentes órganos y sistemas corporales, e incluso la muerte. A nivel del SNC destaca, por su gravedad e incidencia, la patología cerebro-vascular hemorrágica (PCVH. Este tipo de cuadro se halla asociado al consumo de drogas ilícitas entre el 9,5% y el 34% de los accidentes vasculares en menores de 45 años, siendo la cocaína la más frecuentemente implicada en su presentación. Por otro lado, la rotura de un aneurisma o malformación arteriovenosa se ha detectado hasta en el 50% de los pacientes con PCVH secundarios al consumo de cocaína. Presentamos tres casos de muerte súbita en adultos por patología cerebro-vascular hemorrágica asociada al consumo de cocaína.Cocaine is the second most frequent illegal drug consumed in Spain after cannabis. A significant increase has occurred in the number of individuals treated in emergency departments after cocaine use just as in the number of cocaine-related deaths. These rates have been actually multiplied by six in the latest years. Cocaine causes injury in different organ systems, even death. In the CNS the use of cocaine is frequently associated with cerebral haemorrhage. Stroke in young adults below 45 years is usually related to drug use between 9,5% and 34% of cases, and cocaine is the most frequently mentioned drug. Otherwise, even 50% of cocaine-related stroke is the result of rupture of saccular aneurysms involving the arteries at the base of the brain and vascular malformation. In this paper, we present three cases of sudden death in adults due to cerebral haemorrhage associated with cocaine use.

  5. Efecto de la Levadura de cerveza (S. cerevisiae asociada con vitamina E sobre las variables productivas y la calidad de la canal de pollos parrilleros Yeast (S. cerevisiae - E vitamin combination over productive variables and quality carcass in broilers

    Directory of Open Access Journals (Sweden)

    M.J Linares

    2009-06-01

    Full Text Available El objetivo fue verificar la acción de Levadura de Cerveza asociada o no a vitamina E sobre las variables productivas y la calidad de la canal. Ciento veinte pollos parrilleros recibieron dietas Control, Vitamina 1 (V1, 50 ppm. de vitamina E, Vitamina 2 (V2, 100 ppm. de vitamina E, Vitamina 3 (V3, 200 ppm. de vitamina E, y Levadura mas Vitamina (L+V, 0,3 % de Levadura + 200 ppm. de vitamina E; con cuatro repeticiones de seis aves cada una. De los 29 a los 52 días de vida se midieron Ganancia Media Diaria (GMD, Consumo Medio Diario (CMD e Índice de Conversión (IC, se determinaron % de Rendimiento de la canal (RC, Peso de Pechuga (% (PP, Peso de Muslos (% (PM y Peso de Grasa (% (PG. Se realizó un ANOVA con posterior test de Tukey, p≤ 0,05 fueron considerados significativos. Las aves que recibieron la asociación tuvieron significativamente mejor IC, mayor PM y menor PG, respecto a las otras. Se concluye que la combinación de la Levadura y la Vitamina E mejoró la performance productiva y la calidad de la canal al mejorar el IC, reducir el PG y aumentar el PM en las aves que la recibieron.The aim was to estimate the action of yeast (S. Cerevisiae-vitamin E combinated or not over the productive variables and quality carcass. One hundred and twenty male broilers Cobb received the following diets: Control, Vitamin 1 (V1, 50 ppm E vitamin, Vitamin 2 (V2, 100 ppm E vitamin, Vitamin 3 (V3, 200 ppm E vitamin and Yeast plus Vitamin (Y+V, 0,3 % yeast + 200 pp E vitamin with six chicken per pen and four pen for ration Since 29 till 52 days old the Average Daily Consumption (ADC, Average Daily Gain (ADG and Conversion Index (CI were measured. % carcass yield (CY, % breast weigh (BW, % leg muscles weigh (LMW and % fat weigh (FW were determinated. An ANOVA and a tukey test were made, significant differences were considered if p≤ 0,05. The broiler that received the combination of yeast and E vitamin had significantly best CI and hight LMW and lower FW

  6. Aportes teóricos y metodológicos para evaluar el impacto en la salud asociada al uso nocivo de alcohol Theoretical and methodological contributions to assess the health impact associated with the harmful use of alcohol

    Directory of Open Access Journals (Sweden)

    Ernesto Cortés Amador

    2012-06-01

    Full Text Available El uso nocivo de alcohol se encuentra asociado con más de sesenta padecimientos crónicos y agudos y es uno de los principales factores de riesgo de morbilidad y mortalidad a nivel mundial, especialmente en el continente americano. Objetivo: Aclarar el panorama en cuanto a la morbilidad y mortalidad asociada al consumo de alcohol, así como una propuesta metodología para su medición en la sociedad costarricense; como parte de la construcción de un sistema de vigilancia epidemiológica sobre el impacto del uso nocivo de alcohol. Desarrollo: En Costa Rica existe una gran variedad de evidencia y fuentes de información para medir el impacto del consumo de bebidas alcohólicas en la salud pública, pero aún existen vacios en la calidad de la producción de los datos, lo que dificulta su análisis. Conclusión: Es claro que el alcohol tiene un gran impacto en la salud pública de la población costarricense, principalmente para los hombres, tanto jóvenes por condiciones agudas, como para los adultos y adultos mayores por enfermedades crónicas.Harmful use of alcohol is associated with more than sixty chronic and acute health conditions, and is one of the main risk factors for morbidity and mortality worldwide, especially in the American continent. Objective: This paper intends to shed light on morbidity and mortality associated with alcohol use, and to propose a measurement methodology for Costa Rican society, as part of an effort to construct an epidemiological surveillance system regarding harmful use of alcohol. Main thesis: In Costa Rica there is a variety of evidence and information sources to measure the impact of alcohol on public health, but there are still gaps in the quality of the produced data, which hinders analysis. Conclusion: It is clear that alcohol has a great impact on public health in the Costa Rica population, especially on men, both for young adults with acute conditions and the elderly due to chronic illness.

  7. Hiperalgesia asociada al tratamiento con opioides

    Directory of Open Access Journals (Sweden)

    A. Gil Martín

    2014-10-01

    Full Text Available La hiperalgesia inducida por opioides es una reacción paradójica caracterizada por una percepción intensificada de dolor relacionada con el uso de estos medicamentos en ausencia de progresión de la enfermedad o de síndrome de retirada. A diferencia de los casos de tolerancia, definida como pérdida de potencia analgésica durante el uso prolongado de opioides, no se produce mejoría con el escalado de dosis. La hiperalgesia inducida por opioides se ha manifestado en pacientes con dosis de mantenimiento y retirada, pacientes con dosis elevadas o escalado de dosis y pacientes con dosis ultra bajas. Para establecer un diagnóstico diferencial es importante tener en cuenta que un incremento de dosis puede producir una mejoría temporal en pacientes con tolerancia pero no en los que han desarrollado hiperalgesia. La prevalencia de dicho fenómeno es desconocida, pero puede ser más frecuente de lo esperado y muchas veces no reconocido. El mecanismo subyacente no está bien definido, pero existen diversos estudios experimentales tanto en modelos animales como en humanos en los que se observa que la hiperalgesia no está desencadenada por un único factor, sino que son muchos los implicados. Entre los mecanismos propuestos destacan: la mediación del receptor NMDA (N-metil-D-aspartato activado por la liberación presináptica de glutamato, la modulación por la proteína-kinasa de calcio/calmodulina, el aumento en el número de nociceptores o la liberación de neurotransmisores excitadores. Se han realizado diversos estudios para describir la expresión y la relevancia de la hiperalgesia inducida por opioides en distintos grupos de pacientes: ex-adictos a opioides en tratamiento de mantenimiento con metadona, en exposición perioperatoria, en voluntarios sanos o en dolor crónico. Existen diferentes estrategias de tratamiento disponibles; entre las más aceptadas se encuentra la reducción en la dosis del opioide utilizado, la rotación del opioide o la asociación al tratamiento de otro tipo de analgésico. Otras opciones son los antagonistas del receptor NMDA o la terapia combinada con los inhibidores de la COX-2. En el presente trabajo se revisan los avances recientes en el conocimiento de los mecanismos subyacentes que la producen, los estudios clínicos realizados así como las diferentes estrategias de tratamiento disponibles.

  8. Root Associated Bacteria – Friends or Enemies? A Review

    Directory of Open Access Journals (Sweden)

    Gabriela Mihalache

    2015-10-01

    Full Text Available Plant roots, due to their exudates, represent important ecological niches for bacteria, which can influence the plant growth by their both beneficial and deleterious effects. The positive effects of bacteria interaction with the plants roots consist in facilitating the nutrient uptake (N, P, producing phytohormones, enhancing their resistance to biotic and abiotic factors such as pathogenic fungi and bacteria, extreme temperatures, heavy metals, salinity. Regarding the harmful effects of bacteria on plants growth, production of phytotoxins, competition for nutrients or inducing diseases or even plants death represents examples of mechanisms by which bacteria can affect in a negative manner the growth of the plants.

  9. Probiotic bacteria in prevention and treatment of diarrhea

    Directory of Open Access Journals (Sweden)

    Jasmina Havranek

    2009-03-01

    Full Text Available Probiotic bacteria have beneficial effects in prevention and treatment of different diseases. The results of preventive and therapeutic effect of probiotic bacteria on diarrhea during last ten years are shown in this paper. The greatest preventive and therapeutic effect of probiotic bacteria was identified for acute diarrhea in children caused by rotaviruses. Significant, but slightly lower effect of probiotic bacteria was proved for antibiotic associated diarrhea. Positive effect in prevention of traveller’s diarrhea and radiation-induced diarrhea is not significant. Preventive and therapeutic effect on diarrhea is not dependent on the way of probiotic bacteria consumption, by fermented milk, capsule or oral rehydration solution.

  10. Seeing green bacteria in a new light: genomics-enabled studies of the photosynthetic apparatus in green sulfur bacteria and filamentous anoxygenic phototrophic bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Bryant, Donald A

    2004-01-01

    Based upon their photosynthetic nature and the presence of a unique light-harvesting antenna structure, the chlorosome, the photosynthetic green bacteria are defined as a distinctive group in the Bacteria. However, members of the two taxa that comprise this group, the green sulfur bacteria...... (Chlorobi) and the filamentous anoxygenic phototrophic bacteria ("Chloroflexales"), are otherwise quite different, both physiologically and phylogenetically. This review summarizes how genome sequence information facilitated studies of the biosynthesis and function of the photosynthetic apparatus...... and carotenoid species also allow the functions of these pigments to be studied in vivo....

  11. Population of Nitrifying Bacteria and Nitrification in Ammonium Saturated Clinoptilolite

    Science.gov (United States)

    McGilloway, R. L.; Weaver, R. W.; Ming, Douglas W.; Gruener, J.

    1999-01-01

    As humans begin to spend longer periods of time in space, plants will be incorporated into life support systems. Ammonium saturated clinoptilolite is one plant growth substrate but a balance between ammonium and nitrate is needed. A laboratory study was conducted to determine effects of nitrifying bacteria on ammonium concentrations and kinetics of nitrification. Columns containing clinoptilolite substrate amended with nitrifying bacteria obtained from soil enrichment were analyzed weekly for a 90 day period. The enrichment culture initially contained 1 x 10(exp 5) ammonium oxidizing bacteria and 1 x 10(exp 2) nitrite oxidizing bacteria per gram of substrate. Populations of ammonium oxidizing bacteria increased to 1 x 10(exp 6) and nitrite oxidizing bacteria increased to 1 x 10(exp 3) per gram of substrate. The nitrification rate was approximately 0.25mg NO3(-)-N/kg.hr. Experiments were also conducted to enumerate nitrifying bacteria in a clinoptilolite substrate used to grow wheat (Triticum aestivum L.). Seventy days following the initial inoculation with an unknown number of commercial nitrifying bacteria, 1 x 10(exp 5) ammonium oxidizing bacteria per gram of substrate were present. The number of nitrite oxidizing bacteria was between 1 x 10(exp 3) to 10(exp 4) per gram of substrate as measured by the most probable number method. Nitrification rates were approximately 0.20mg NO3(-)-N/kg.hr. Clinoptilolite readily exchanged sufficient concentrations of ammonium to support nitrifying bacteria and they survived well in this medium.

  12. Design and application of the method for isolating magnetotactic bacteria

    Institute of Scientific and Technical Information of China (English)

    XIAO Zhijie; LIAN Bin; CHEN Jun; H. Henry Teng

    2007-01-01

    A simple apparatus was designed to effectively isolate magnetotactic bacteria from soils or sediments based on their magnetotaxis. Through a series of processes including sample incubation, MTB harvesting, isolation, purification and identification, several strains of bacteria were isolated from the samples successfully. By Transmission Electron Microscopy (TEM) and Energy-Dispersive X-ray Analysis (EDXA), these bacteria were certificated to be magnetotactic bacteria. The phylogenetic relationship between the isolated magnetic strains and some known magnetotactic bacteria was inferred by the construction of phylogenetic tree based on 16SrDNA sequences. This apparatus has been proven to have the advantages of being inexpensive, simple to assemble, easy to perform and highly efficient to isolate novel magnetotactic bacteria. The research indicated that the combined approach of harvesting MTB by home-made apparatus and the method of plate colony isolation could purify and isolate magnetotactic bacteria effectively.

  13. Computational Challenges in Characterization of Bacteria and Bacteria-Host Interactions Based on Genomic Data

    Institute of Scientific and Technical Information of China (English)

    Chao Zhang; Guo-lu Zheng; Shun-Fu Xu; Dong Xu

    2012-01-01

    With the rapid development of next-generation sequencing technologies,bacterial identification becomes a very important and essential step in processing genomic data,especially for metagenomic data.Many computational methods have been developed and some of them are widely used to address the problems in bacterial identification.In this article we review the algorithms of these methods,discuss their drawbacks,and propose future computational methods that use genomic data to characterize bacteria.In addition,we tackle two specific computational problems in bacterial identification,namely,the detection of host-specific bacteria and the detection of disease-associated bacteria,by offering potential solutions as a starting point for those who are interested in the area.

  14. Do foliar endophytic bacteria fix nitrogen?

    Science.gov (United States)

    Kueppers, L. M.; Moyes, A. B.; Frank, C.; Pett-Ridge, J.; Carper, D.; Vandehey, N.; O'Neil, J.; Dekas, A.

    2015-12-01

    Endophytic microorganisms - bacteria and fungi that live inside healthy plant tissue - are a relatively unexplored source of functional diversity in natural ecosystems. Prior to modern sequencing technology, detecting uncultured endophytic bacteria and assessing their putative functions was challenging. However, recent work has revealed a remarkable diversity of as yet non-culturable endophytic taxa and is beginning to identify functional roles within plant microbiomes. We recently examined bacterial communities in the foliage of a long-lived, high-elevation conifer species, limber pine (Pinus flexilis), and discovered a community strongly dominated by acetic acid bacteria (Acetobacteraceae), with several taxa closely related to known nitrogen fixers. Given limber pine's status as a pioneer species that is able to grow in low fertility soils, we hypothesized that this bacterial community has a potential functional role in fixing atmospheric nitrogen, providing a source of this limiting nutrient to the host tree. We used the radioisotope 13N2 to confirm that N2 rapidly diffuses into pine needles, where it could potentially be fixed. With an acetylene reduction assay we confirmed nitrogenase enzyme activity inside excised twigs 4 times over a growing season, and estimate potential rates of N2 fixation at 0.1 nmol N2 g needle-1 hr-1. Scaled to the stand level, this N input could be on the order of ~20 mg N m-2 d-1 over a growing season. While these rates are low, the long lifespan of individual trees (~1000 years) makes them biologically meaningful. Still, measured rates of acetylene reduction and bulk 15N2 incorporation are quite variable in space and time. Much work remains to better characterize the plant-microbial interactions in this system, including the rates of nitrogen fixation and their variability over the growing season, across edaphic conditions, among host species, and through plant development; and to determine which community members are responsible

  15. Close Encounters of Lymphoid Cells and Bacteria

    Science.gov (United States)

    Cruz-Adalia, Aranzazu; Veiga, Esteban

    2016-01-01

    During infections, the first reaction of the host against microbial pathogens is carried out by innate immune cells, which recognize conserved structures on pathogens, called pathogen-associated molecular patterns. Afterward, some of these innate cells can phagocytose and destroy the pathogens, secreting cytokines that would modulate the immune response to the challenge. This rapid response is normally followed by the adaptive immunity, more specific and essential for a complete pathogen clearance in many cases. Some innate immune cells, usually named antigen-presenting cells, such as macrophages or dendritic cells, are able to process internalized invaders and present their antigens to lymphocytes, triggering the adaptive immune response. Nevertheless, the traditional boundary of separated roles between innate and adaptive immunity has been blurred by several studies, showing that very specialized populations of lymphocytes (cells of the adaptive immunity) behave similarly to cells of the innate immunity. These “innate-like” lymphocytes include γδ T cells, invariant NKT cells, B-1 cells, mucosal-associated invariant T cells, marginal zone B cells, and innate response activator cells, and together with the newly described innate lymphoid cells are able to rapidly respond to bacterial infections. Strikingly, our recent data suggest that conventional CD4+ T cells, the paradigm of cells of the adaptive immunity, also present innate-like behavior, capturing bacteria in a process called transinfection. Transinfected CD4+ T cells digest internalized bacteria like professional phagocytes and secrete large amounts of proinflammatory cytokines, protecting for further bacterial challenges. In the present review, we will focus on the data showing such innate-like behavior of lymphocytes following bacteria encounter.

  16. Clay-Bacteria Systems and Biofilm Production

    Science.gov (United States)

    Steiner, J.; Alimova, A.; Katz, A.; Steiner, N.; Rudolph, E.; Gottlieb, P.

    2007-12-01

    Soil clots and the aerosol transport of bacteria and spores are promoted by the formation of biofilms (bacteria cells in an extracellular polymeric matrix). Biofilms protect microorganisms by promoting adhesion to both organic and inorganic surfaces. Time series experiments on bacteria-clay suspensions demonstrate that biofilm growth is catalyzed by the presence of hectorite in minimal growth media for the studied species: Gram negatives (Pseudomonas syringae and Escherichia coli,) and Gram positives (Staphylococcus aureus and Bacillus subtilis). Soil organisms (P. syringae, B. subtilis) and organisms found in the human population (E. coli, S. aureus) are both used to demonstrate the general applicability of clay involvement. Fluorescent images of the biofilms are acquired by staining with propidium iodide, a component of the BacLightTM Live/Dead bacterial viability staining kit (Molecular Probes, Eugene, OR). The evolving polysaccharide-rich biofilm reacts with the clay interlayer site causing a complex substitution of the two-water hectorite interlayer with polysaccharide. The result is often a three-peak composite of the (001) x-ray diffraction maxima resulting from polysaccharide-expanded clays and an organic-driven contraction of a subset of the clays in the reaction medium. X-ray diffractograms reveal that the expanded set creates a broad maximum with clay subsets at 1.84 nm and 1.41 nm interlayer spacings as approximated by a least squares double Lorentzian fit, and a smaller shoulder at larger 2q, deriving from a contraction of the interlayer spacing. Washing with chlorox removes organic material from the contracted clay and creates a 1-water hectorite single peak in place of the double peak. The clay response can be used as an indirect indicator of biofilm in an environmental system.

  17. Turning bacteria suspensions into a "superfluid"

    CERN Document Server

    López, Héctor Matías; Douarche, Carine; Auradou, Harold; Clément, Eric

    2015-01-01

    The rheological response under simple shear of an active suspension of Escherichia coli is determined in a large range of shear rates and concentrations. The effective viscosity and the time scales characterizing the bacterial organization under shear are obtained. In the dilute regime, we bring evidences for a low shear Newtonian plateau characterized by a shear viscosity decreasing with concentration. In the semi-dilute regime, for particularly active bacteria, the suspension display a "super-fluid" like transition where the viscous resistance to shear vanishes, thus showing that macroscopically, the activity of pusher swimmers organized by shear, is able to fully overcome the dissipative effects due to viscous loss.

  18. Heterotrophic bacteria associated with Varroa destructor mite

    OpenAIRE

    Vanikova, Slavomira; Noskova, Alzbeta; Pristas, Peter; Judova, Jana; Javorsky, Peter

    2015-01-01

    International audience Varroa bee hive attack is a serious and common problem in bee keeping. In our work, an ecto-microflora of Varroa destructor mites was characterised as a potential source of bacterial bee diseases. Using a cultivation approach, a variable population of bacteria was isolated from the body surface of Varroa mites with frequency of about 150 cfu per mite individual. Nine studied isolates were classified to four genera and six species by a combination of matrix-assisted l...

  19. Electroactive biofilms of sulphate reducing bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Cordas, Cristina M.; Guerra, L. Tiago; Xavier, Catarina [Requimte-CQFB, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Moura, Jose J.G. [Requimte-CQFB, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)], E-mail: jose.moura@dq.fct.unl.pt

    2008-12-01

    Biofilms formed from a pure strain of Desulfovibrio desulfuricans 27774 on stainless steel and graphite polarised surfaces were studied. The polarisation conditions applied were -0.4 V vs. SCE for different times. A cathodic current related with the biofilms growth was observed with a maximum intensity of -270 mA m{sup -2} that remained stable for several days using graphite electrodes. These sulphate reducing bacteria biofilms present electrocatalytic activity towards hydrogen and oxygen reduction reactions. Electrode polarisation has a selective effect on the catalytic activity. The biofilms were also observed by scanning electronic microscopy revealing the formation of homogeneous films on the surfaces.

  20. Bacteria: prospective savior in battle against cancer.

    Science.gov (United States)

    Nair, Neha; Kasai, Tomonari; Seno, Masaharu

    2014-11-01

    Conventional anticancer therapies such as chemotherapy are losing their sheen in the battle against cancer. Therefore, strategies for treatment of cancer need to be constantly modified to fulfill the growing demands of alternative therapies. Several viral and non-viral vectors have been exploited for anticancer gene therapy. But over the years bacteria have been proven to be an important candidate for successful evasion of cancer. They serve as invaluable source of tumor-specific anticancer genes, toxins, polysaccharides for synthesis of nanodrugs and gene-delivery vectors. The current review assesses the role of important bacterial groups in different spheres of anti-cancer research. PMID:25368227

  1. Evaluación de pasturas de Brachiaria decumbens solas o asociadas con Centrosema acutifolium con ganado de doble propósito: I. Evaluación de la disponibilidad, composición botánica, frecuencia y calidad forrajera

    Directory of Open Access Journals (Sweden)

    Ramírez Náder Luis Miguel

    1991-12-01

    . decumbens in associate pasture was more higher 6.4% than alone pasture 5.2 %. The IN VITRO digestibility for the dry matter (IVDM was lower for th C. acutifolium , related to the B. decumbens in associate pasture and m alone pasture, with means of 37.9, 55,2 and 55,2% respectively.

    La investigación se realizó en Florida, Valle del Cauca, al suroccidente de Colombia (3° 20' N; 76° 14' 0; 1150 m de altitud, temperatura media 25°C; precipitación media anual de 1.339 m en un área de suelos INCEPTISOLES ligeramente ácidos (pH 5.8-6.3. Se utilizaron 4 praderas de 4 ha, cada una, dos de ellas establecidas con B. decumbens solo y las otras dos con B. decumbens asociado, las cuales se pastorearon en forma alterna cada 21 días asignándose una carga de 1.5 animales/ha. Las evaluaciones se realizaron utilizando el método de muestreo de BOTANAL-2. Hubo mayor disponibilidad de Materia Seca Verde de gramínea (MSVG y de leguminosa (MSVL, así como de Materia Seca Total (MST en la pastura asociada que en la pastura sola, a través de todos los períodos de medición, con medias de 4.627 vs. 2.296; 689 vs 45; kg/ha y 6.476 vs. 3.698 kg/ha respectivamente. En contraste hubo menor disponibilidad de Materia Seca Verde de malezas (MSVM y la del material inerte (MSMI en la pastura asociada en relación a la pastura sola, con medias de 265 vs 345 y 631 vs 798 kg/ha, respectivamente. La composición botánica presentó proporciones más estables y mayores de gramínea 72% y de leguminosa 11%en la pastura asociada, que en la pastura sola con 65 y 1%, respectivamente. La frecuencia de presencia de B. decumbens fue similar en las pasturas asociada, 96% y sola 98%. La frecuencia de C. acutifolium fue mayor en la pastura asociada 81%, que en la pastura sola 12%. Así mismo, en la pastura asociada se obtuvieron los menores valores en la frecuencia de malezas 47% y material inerte 84% que en la pastura sola con 52 y 97% respectivamente. El porcentaje de suelo descubierto fue menor en la

  2. The talking language in some major Gram-negative bacteria.

    Science.gov (United States)

    Banerjee, Goutam; Ray, Arun Kumar

    2016-08-01

    Cell-cell interaction or quorum sensing (QS) is a vital biochemical/physiological process in bacteria that is required for various physiological functions, including nutrient uptake, competence development, biofilm formation, sporulation, as well as for toxin secretion. In natural environment, bacteria live in close association with other bacteria and interaction among them is crucial for survival. The QS-regulated gene expression in bacteria is a cell density-dependent process and the initiation process depends on the threshold level of the signaling molecule, N-acyl-homoserine lactone (AHL). The present review summarizes the QS signal and its respective circuit in Gram-negative bacteria. Most of the human pathogens belong to Gram-negative group, and only a few of them cause disease through QS system. Thus, inhibition of pathogenic bacteria is important. Use of antibiotics creates a selective pressure (antibiotics act as natural selection factor to promote one group of bacteria over another group) for emerging multidrug-resistant bacteria and will not be suitable for long-term use. The alternative process of inhibition of QS in bacteria using different natural and synthetic molecules is called quorum quenching. However, in the long run, QS inhibitors or blockers may also develop resistance, but obviously it will solve some sort of problems. In this review, we also have stated the mode of action of quorum-quenching molecule. The understanding of QS network in pathogenic Gram-negative bacteria will help us to solve many health-related problems in future. PMID:27062655

  3. Co-electrospinning of bacteria and viruses

    Science.gov (United States)

    Salalha, Wael; Kuhn, Jonathan; Chervinsky, Shmuel; Zussman, Eyal

    2006-03-01

    Co-electrospinning provides a novel and highly versatile approach towards composite fibers with diameters ranging from a few hundred nm down to 30 nm with embedded elements. In the present work, co-electrospinning of poly(vinyl alcohol) (PVA) and viruses (T7, T4, λ) or bacteria (Escherichia coli, Staphylococcus albus) was carried out. These preparations should have applications for tissue engineering, gene therapy, phage therapy and biosensing. The average diameter of the co-spun nanofibers was about 300 nm. We found that the encapsulated viruses and bacteria manage to survive the electrospinning process, its pressure buildup in the core of the fiber and the electrostatic field in the co-electrospinning process. Approximately 10% of the Escherichia coli and 20% of Staphylococcus albus cells are viable after spinning. Approximately 5% of the bacterial viruses were also viable after the electrospinning. It should be noted that the encapsulated cells and viruses remain stable for two months without a further decrease in number. These results demonstrate the potential of the co-electrospinning process for the encapsulation and immobilization of bio-objects and the possibility of adapting them to technical applications (e.g., bio-chips).

  4. Accumulation of swimming bacteria near an interface

    Science.gov (United States)

    Tang, Jay; Li, Guanglai

    2012-11-01

    Microbes inhabit planet earth over billions of years and have adapted to diverse physical environment of water, soil, and particularly at or near interfaces. We focused our attention on the locomotion of Caulobacter crescentus, a singly flagellated bacterium, at the interface of water/solid or water/air. We measured the distribution of a forward swimming strain of C. crescentus near a surface using a three-dimensional tracking technique based on dark field microscopy and found that the swimming bacteria accumulate heavily within a micrometer from the surface. We attribute this accumulation to frequent collisions of the swimming cells with the surface, causing them to align parallel to the surface as they continually move forward. The extent of accumulation at the steady state is accounted for by balancing alignment caused by these collisions with rotational Brownian motion of the micrometer-sized bacteria. We performed a simulation based on this model, which reproduced the measured results. Additional simulations demonstrate the dependence of accumulation on swimming speed and cell size, showing that longer and faster cells accumulate more near a surface than shorter and slower ones do. The overarching goal of our study is to describe interfacial microbial behavior through detailed analysis of their motion. We acknowledge support by NSF PHY 1058375.

  5. Magnetotactic bacteria on Earth and on Mars.

    Science.gov (United States)

    McKay, Christopher P; Friedmann, E Imre; Frankel, Richard B; Bazylinski, Dennis A

    2003-01-01

    Continued interest in the possibility of evidence for life in the ALH84001 Martian meteorite has focused on the magnetite crystals. This review is structured around three related questions: is the magnetite in ALH84001 of biological or non-biological origin, or a mixture of both? does magnetite on Earth provide insight to the plausibility of biogenic magnetite on Mars? could magnetotaxis have developed on Mars? There are credible arguments for both the biological and non-biological origin of the magnetite in ALH84001, and we suggest that more studies of ALH84001, extensive laboratory simulations of non-biological magnetite formation, as well as further studies of magnetotactic bacteria on Earth will be required to further address this question. Magnetite grains produced by bacteria could provide one of the few inorganic traces of past bacterial life on Mars that could be recovered from surface soils and sediments. If there was biogenic magnetite on Mars in sufficient abundance to leave fossil remains in the volcanic rocks of ALH84001, then it is likely that better-preserved magnetite will be found in sedimentary deposits on Mars. Deposits in ancient lakebeds could contain well-preserved chains of magnetite clearly indicating a biogenic origin.

  6. Inoculation of sugarcane with diazotrophic bacteria

    Directory of Open Access Journals (Sweden)

    Nivaldo Schultz

    2014-04-01

    Full Text Available The sugarcane industry, a strategic crop in Brazil, requires technological improvements in production efficiency to increase the crop energy balance. Among the various currently studied alternatives, inoculation with diazotrophic bacteria proved to be a technology with great potential. In this context, the efficiency of a mixture of bacterial inoculant was evaluated with regard to the agronomic performance and N nutrition of sugarcane. The experiment was carried out on an experimental field of Embrapa Agrobiologia, in Seropédica, Rio de Janeiro, using a randomized block, 2 × 3 factorial design (two varieties and three treatments with four replications, totaling 24 plots. The varieties RB867515 and RB72454 were tested in treatments consisting of: inoculation with diazotrophic bacteria, N-fertilized control with 120 kg ha-1 N and absolute control (no inoculation and no N fertilizer. The inoculum was composed of five strains of five diazotrophic species. The yield, dry matter accumulation, total N in the shoot dry matter and the contribution of N by biological fixation were evaluated, using the natural 15N abundance in non-inoculated sugarcane as reference. The bacterial inoculant increased the stalk yield of variety RB72454 similarly to fertilization with 120 kg ha-1 N in the harvests of plant-cane and first ratoon crops, however the contribution of biological N fixation was unchanged by inoculation, indicating that the benefits of the inoculant in sugarcane may have resulted from plant growth promotion.

  7. Insects as alternative hosts for phytopathogenic bacteria.

    Science.gov (United States)

    Nadarasah, Geetanchaly; Stavrinides, John

    2011-05-01

    Phytopathogens have evolved specialized pathogenicity determinants that enable them to colonize their specific plant hosts and cause disease, but their intimate associations with plants also predispose them to frequent encounters with herbivorous insects, providing these phytopathogens with ample opportunity to colonize and eventually evolve alternative associations with insects. Decades of research have revealed that these associations have resulted in the formation of bacterial-vector relationships, in which the insect mediates dissemination of the plant pathogen. Emerging research, however, has highlighted the ability of plant pathogenic bacteria to use insects as alternative hosts, exploiting them as they would their primary plant host. The identification of specific bacterial genetic determinants that mediate the interaction between bacterium and insect suggests that these interactions are not incidental, but have likely arisen following the repeated association of microorganisms with particular insects over evolutionary time. This review will address the biology and ecology of phytopathogenic bacteria that interact with insects, including the traditional role of insects as vectors, as well as the newly emerging paradigm of insects serving as alternative primary hosts. Also discussed is one case where an insect serves as both host and vector, which may represent a transitionary stage in the evolution of insect-phytopathogen associations. PMID:21251027

  8. Probiotic Lactic Acid Bacteria and Skin Health.

    Science.gov (United States)

    Jeong, Ji Hye; Lee, Chang Y; Chung, Dae Kyun

    2016-10-25

    Human skin is the first defense barrier against the external environment, especially microbial pathogens and physical stimulation. Many studies on skin health with Lactic acid bacteria (LAB) have been published for many years, including prevention of skin disease and improvement of skin conditions. LAB, a major group of gram-positive bacteria, are known to be beneficial to human health by acting as probiotics. Recent studies have shown that LAB and their extracts have beneficial effects on maintenance and improvement of skin health. Oral administration of Lactobacillus delbrueckii inhibits the development of atopic disease. In addition, LAB and LAB extracts are known to have beneficial effects on intestinal diseases, with Lactobacillus plantarum having been shown to attenuate IL-10 deficient colitis. In addition to intestinal health, L. plantarum also has beneficial effects on skin. pLTA, which is lipoteichoic acid isolated from L. plantarum, has anti-photoaging effects on human skin cells by regulating the expression matrix meralloprotionase-1 (MMP-1) expression. While several studies have proposed a relationship between diseases of the skin and small intestines, there are currently no published reviews of the effects of LAB for skin health through regulation of intestinal conditions and the immune system. In this review, we discuss recent findings on the effects of LAB on skin health and its potential applications in beauty foods. PMID:26287529

  9. Detection of phenols using engineered bacteria

    Science.gov (United States)

    Wise, Arlene A.; Kuske, Cheryl R.; Terwilliger, Thomas C.

    2007-12-04

    Detection of phenols using engineered bacteria. A biosensor can be created by placing a reporter gene under control of an inducible promoter. The reporter gene produces a signal when a cognate transcriptional activator senses the inducing chemical. Creation of bacterial biosensors is currently restricted by limited knowledge of the genetic systems of bacteria that catabolize xenobiotics. By using mutagenic PCR to change the chemical specificity of the Pseudomonas species CF600 DmpR protein, the potential for engineering novel biosensors for detection of phenols has been demonstrated. DmpR, a well-characterized transcriptional activator of the P. CF600's dmp operon mediates growth on simple phenols. Transcription from Po, the promoter heading the dmp operon, is activated when the sensor domain of DmpR interacts with phenol and mono-substituted phenols. By altering the sensor domain of the DmpR, a group of DmpR derivatives that activate transcription of a Po-lacZ fusion in response to eight of the EPA's eleven priority pollutant phenols has been created. The assays and the sensor domain mutations that alter the chemical specificity of DmpR is described.

  10. Bioactivation of Phytoestrogens: Intestinal Bacteria and Health.

    Science.gov (United States)

    Landete, J M; Arqués, J; Medina, M; Gaya, P; de Las Rivas, B; Muñoz, R

    2016-08-17

    Phytoestrogens are polyphenols similar to human estrogens found in plants or derived from plant precursors. Phytoestrogens are found in high concentration in soya, flaxseed and other seeds, fruits, vegetables, cereals, tea, chocolate, etc. They comprise several classes of chemical compounds (stilbenes, coumestans, isoflavones, ellagitannins, and lignans) which are structurally similar to endogenous estrogens but which can have both estrogenic and antiestrogenic effects. Although epidemiological and experimental evidence indicates that intake of phytoestrogens in foods may be protective against certain chronic diseases, discrepancies have been observed between in vivo and in vitro experiments. The microbial transformations have not been reported so far in stilbenes and coumestans. However, isoflavones, ellagitanins, and lignans are metabolized by intestinal bacteria to produce equol, urolithins, and enterolignans, respectively. Equol, urolithin, and enterolignans are more bioavailable, and have more estrogenic/antiestrogenic and antioxidant activity than their precursors. Moreover, equol, urolithins and enterolignans have anti-inflammatory effects and induce antiproliferative and apoptosis-inducing activities. The transformation of isoflavones, ellagitanins, and lignans by intestinal microbiota is essential to be protective against certain chronic diseases, as cancer, cardiovascular disease, osteoporosis, and menopausal symptoms. Bioavailability, bioactivity, and health effects of dietary phytoestrogens are strongly determined by the intestinal bacteria of each individual.

  11. Bioactivation of Phytoestrogens: Intestinal Bacteria and Health.

    Science.gov (United States)

    Landete, J M; Arqués, J; Medina, M; Gaya, P; de Las Rivas, B; Muñoz, R

    2016-08-17

    Phytoestrogens are polyphenols similar to human estrogens found in plants or derived from plant precursors. Phytoestrogens are found in high concentration in soya, flaxseed and other seeds, fruits, vegetables, cereals, tea, chocolate, etc. They comprise several classes of chemical compounds (stilbenes, coumestans, isoflavones, ellagitannins, and lignans) which are structurally similar to endogenous estrogens but which can have both estrogenic and antiestrogenic effects. Although epidemiological and experimental evidence indicates that intake of phytoestrogens in foods may be protective against certain chronic diseases, discrepancies have been observed between in vivo and in vitro experiments. The microbial transformations have not been reported so far in stilbenes and coumestans. However, isoflavones, ellagitanins, and lignans are metabolized by intestinal bacteria to produce equol, urolithins, and enterolignans, respectively. Equol, urolithin, and enterolignans are more bioavailable, and have more estrogenic/antiestrogenic and antioxidant activity than their precursors. Moreover, equol, urolithins and enterolignans have anti-inflammatory effects and induce antiproliferative and apoptosis-inducing activities. The transformation of isoflavones, ellagitanins, and lignans by intestinal microbiota is essential to be protective against certain chronic diseases, as cancer, cardiovascular disease, osteoporosis, and menopausal symptoms. Bioavailability, bioactivity, and health effects of dietary phytoestrogens are strongly determined by the intestinal bacteria of each individual. PMID:25848676

  12. Magnetotactic bacteria and magnetosomes - Scope and challenges.

    Science.gov (United States)

    Jacob, Jobin John; Suthindhiran, K

    2016-11-01

    Geomagnetism aided navigation has been demonstrated by certain organisms which allows them to identify a particular location using magnetic field. This attractive technique to recognize the course was earlier exhibited in numerous animals, for example, birds, insects, reptiles, fishes and mammals. Magnetotactic bacteria (MTB) are one of the best examples for magnetoreception among microorganisms as the magnetic mineral functions as an internal magnet and aid the microbe to move towards the water columns in an oxic-anoxic interface (OAI). The ability of MTB to biomineralize the magnetic particles (magnetosomes) into uniform nano-sized, highly crystalline structure with uniform magnetic properties has made the bacteria an important topic of research. The superior properties of magnetosomes over chemically synthesized magnetic nanoparticles made it an attractive candidate for potential applications in microbiology, biophysics, biochemistry, nanotechnology and biomedicine. In this review article, the scope of MTB, magnetosomes and its challenges in research and industrial application have been discussed in brief. This article mainly focuses on the application based on the magnetotactic behaviour of MTB and magnetosomes in different areas of modern science. PMID:27524094

  13. Sulphur bacteria mediated formation of Palaeoproterozoic phosphorites

    Science.gov (United States)

    Joosu, Lauri; Lepland, Aivo; Kirsimäe, Kalle

    2014-05-01

    Modern phosphorite formation is typically associated with high productivity in upwelling areas where apatite (Ca-phosphate) precipitation is mediated by sulphur oxidising bacteria [1]. They inhabit the oxic/anoxic interface within the upper few centimetres of sediment column, accumulating phosphate in their cells under oxic conditions and releasing it rapidly when conditions become anoxic. Sulphur bacteria are known to live in close association with a consortium of anaerobic methane oxidising archaea and syntrophic sulphate-reducing bacteria. Paleoproterozoic, c. 2.0 Ga Zaonega Formation in Karelia, Russia contains several P-rich intervals in the upper part of 1500 m thick succession of organic-rich sedimentary rocks interlayered with mafic tuffs and lavas. Apatite in these P-rich intervals forms impure laminae, lenses and round-oval nodules which diameters typically range from 300 to 1000 μm. Individual apatite particles in P-rich laminae and nodules commonly occur as cylinders that are 1-8 μm long and have diameters of 0.5-4 μm. Cross-sections of best preserved cylindrical apatite particles reveal a thin outer rim whereas the internal parts consist of small anhedral elongated crystallites, intergrown with carbonaceous material. During recrystallization the outer rim thickens towards interior and cylinders may attain hexagonal crystal habit, but their size and shape remains largely unchanged [2]. The sizes of Zaonega nodules are similar to giant sulphide-oxidising bacteria known from modern and ancient settings [3, 4]. Individual apatite cylinders and aggregates have shapes and sizes similar to the methanotrophic archaea that inhabit microbial mats in modern seep/vent areas where they operate in close associations with sulphur-oxidising microbial communities [5]. Seep/vent influence during the Zaonega phosphogenesis is indicated by variable, though positive Eu anomaly, expected in magmatically active sedimentary environment experiencing several lava flows

  14. Anafilaxia associada à vacina contra sarampo, caxumba e rubéola Anafilaxia asociada a la vacuna contra sarampión, varicela y rubéola Anaphylaxis associated with the vaccine against measles, mumps and rubella

    Directory of Open Access Journals (Sweden)

    Iolanda Maria Novadzki

    2010-04-01

    Full Text Available Estudo do tipo caso-controle cujo objetivo foi descrever os casos e as causas de anafilaxia associada à vacina contra sarampo, caxumba e rubéola. Foram estudados 22 casos notificados em crianças de Curitiba, PR, durante Campanha Nacional de Vacinação de 2004, que apresentaram manifestações mucocutâneas. Para o controle, foram selecionadas 66 crianças vizinhas dos casos, que não apresentaram sintomatologia após a aplicação vacinal. Foram realizadas dosagens séricas de anticorpos para os antígenos vacinais, IgE total e específicas para diversos alérgenos, e testes cutâneos. A resposta vacinal foi adequada, a dosagem de IgE específica e os testes cutâneos mostraram que os alérgenos potenciais constituintes da vacina e a atopia não foram relacionados às reações anafiláticas. Os testes cutâneos com a vacina e o dextrano foram positivos somente nos casos, sugerindo sensibilização por algum componente residual da vacina e possível reação cruzada com o dextrano.Estudio del tipo caso-control cuyo objetivo fue describir los casos y las causas de anafilaxia asociada a la vacuna contra sarampión, varicela y rubéola. Fueron estudiados 22 casos notificados en niños de Curitiba, Sureste de Brasil, durante Campaña Nacional de Vacunación de 2004, que presentaron manifestaciones mococutáneas. Para el control, fueron seleccionados 66 niños vecinos de los casos, que no presentaron sintomatología posterior a la aplicación vacunal. Fueron realizadas dosificaciones séricas de anticuerpos para los antígenos vacunales, IgE total y específicas para diversos alérgenos, y pruebas cutáneas. La respuesta vacunal fue adecuada, la dosificación de IgE específica y las pruebas cutáneas mostraron que los alérgenos potenciales constituyentes de la vacuna y la atopia no fueron relacionados a las reacciones anafilácticas. Las pruebas cutáneas con la vacuna y el dextrano fueron positivas solamente en los casos, sugiriendo

  15. Infección por el Virus de Inmunodeficiencia Humana y conductas de riesgo asociadas en un Centro Penitenciario de Montevideo, Uruguay HIV infection and associated risk behaviours in a prison in Montevideo, Uruguay

    Directory of Open Access Journals (Sweden)

    M. Macri Troya

    2010-06-01

    Full Text Available Introducción: El objetivo del trabajo consiste en conocer la prevalencia de la infección por VIH y las conductas de riesgo asociadas en reclusos alojados en el Complejo Penitenciario de Montevideo en el año 2005. Material y Método: Se analiza de prevalencia de la infección VIH y las distintas prácticas de riesgo en una muestra de 291 individuos abordada mediante un estudio serológico y entrevista personal a partir de un cuestionario estructurado. Resultados: Se halló una prevalencia de 6.5% para la infección VIH en prisión. Las variables que demostraron ser factores de riesgo para la infección VIH en la prisión fueron: poseer antecedentes de haber estado en prisión (p=0,009; OR= 9,51; IC95%: 1,31-144,0, el haber tenido una pareja sexual VIH (+ en el pasado (p=0,000025; OR=7,87; IC95%: 2,58-23,9, el tener actualmente una pareja VIH (+ (p=0,0013; OR=14,24; IC95%:2,84-70,65, haberse inyectado drogas I/V (p=0,0001; OR=22,6; IC95%: 6,87-78,9, el haberse inyectado drogas I/V en la prisión (p=0,03; OR=4,93; IC95%: 1,10-22,81 y la práctica de compartir el material de inyección (p=0,004; OR=12,5; IC95%: 1,72-114,7.Introduction: The aim of this study is to establish the prevalence of HIV infection and associated risk behaviours amongst inmates at the Montevideo Prison in 2005. Materials and Methods: The prevalence of HIV infection and different risk practices were analysed in a sample of 191 individuals by means of a serological study and personal interview based on a structured questionnaire. Results: A prevalence of 6.5% was found for HIV infection in prison. The variables that proved to be risk factors were: previous prison sentences (p=0.009; OR= 9.51; IC95%: 1.31-144,0, having had an HIV (+ sexual partner in the past (p=0.000025; OR=7.87; IC95%: 2.58-23.9, current relationship with an HIV (+ partner (p=0.0013; OR=14.24; IC95%: 2.84-70.65, intravenous drug use (p=0.0001; OR=22.6; IC95%: 6.87-78.9, intravenous drug use in prison (p=0

  16. Osteonecrosis de maxilares asociada al uso de bifosfonatos: Revisión de 491 casos Osteonecrosis of the jaws associated with use of bisphosphonates: A review of 491 cases

    Directory of Open Access Journals (Sweden)

    S. Hernández Vigueras

    2012-08-01

    Full Text Available En los últimos años, el número de pacientes que presenta osteonecrosis maxilar asociada al uso de bifosfonatos (BIONJ se ha incrementado. Esto es debido al aumento en el consumo de bifosfonatos, los cuales se asocian al tratamiento de carcinomas con metástasis óseas, mieloma múltiple, osteoporosis, osteopenia y enfermedades metabólicas como la enfermedad de Paget. Objetivo: Analizar el número de casos de pacientes que han desarrollado osteonecrosis de maxilares asociado al uso de bifosfonatos, publicados desde Junio del año 2006 hasta Abril 2010. Método: En esta revisión, se consultaron las bases de datos Pubmed-Medline, Scielo e Índice Médico Español, incluyendo límites en la búsqueda, para recopilar los casos de BIONJ que se hayan publicado desde el año 2006 hasta la actualidad. Los artículos seleccionados presentaban casos, en los cuales los pacientes que recibían bifosfonatos desarrollaban BIONJ. Resultados: Se encontraron 491 casos de BIONJ en total, de ellos 49,3% eran mujeres, 32% hombres y 18,7% no se establecía el género. La mayoría de estos casos se presentaron en la mandíbula y asociados particularmente al ácido zolendrónico. Conclusiones: En los próximos años se espera que el número de pacientes que desarrollen esta complicación vaya en aumento, en particular en mujeres, a las cuales se les indica cada vez más esta medicación para el tratamiento de la osteoporosis.In the last years, the number of patients presenting jaw osteonecrosis associated with the use of bisphosphonates (BIONJ has increased. This is due to increased consumption of bisphosphonates, which are associated with the treatment of carcinomas with bone metastases, multiple myeloma, osteoporosis, osteopenia and metabolic diseases such as Paget´s disease. The aim of this review is to analyze the number of cases of patients who developed jaws osteonecrosis-associated with the use of bisphosphonates, published from June 2006 to April 2010. In

  17. Factores de riesgo de aparición de bacteriemia asociada al catéter en pacientes no críticos con nutrición parenteral total

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    María Julia Ocón Bretón

    2013-06-01

    Full Text Available Introducción: La bacteriemia asociada al catéter (BAC es una de las complicaciones más importantes en pacientes portadores de un catéter venoso central (CVC debido a su asociación con un incremento en la mortalidad, morbilidad y gasto sanitario. La administración de nutrición parenteral total (NPT aumenta el riesgo de aparición de BAC. El objetivo de nuestro estudio fue determinar la tasa de incidencia y los factores de riesgo de BAC en pacientes con NPT hospitalizados en plantas médico-quirúrgicas. Métodos: Estudio observacional, analítico, retrospectivo donde se analizaron a todos los pacientes adultos no críticos que precisaron NPT desde enero de 2010 hasta noviembre de 2011. El punto final clínico fue la BAC. La tasa de incidencia de BAC se calculó en forma de episodios por cada 1.000 pacientes-día de cateterización. Los factores predictivos independientes de BAC se determinaron mediante regresión logística. Resultados: Durante el periodo de estudio precisaron NPT un total de 331 pacientes. La duración media del CVC fue de 12,4 (DE 8,7 días y la NPT fue infundida durante un periodo medio de 10,4 (DE 8,3 días. 47 pacientes presentaron BAC, con una tasa de incidencia de 11,4/1.000 pacientes-día de CVC y de 13,7/1.000 pacientes-día de NPT. Los factores predictores univariantes de aparición de BAC fueron la permanencia del CVC superior a 20 días (OR = 2,48; IC 95%: 1,16-5,26, la duración de la NPT superior a 2 semanas (OR = 4,63; IC 95%: 2,16-9,90 y la presencia de fístulas (OR = 3,08; IC 95%: 1,24-7,63. En análisis multivariante, el único predictor independiente de BAC fue la duración de la NPT (OR para una duración superior a 14 días = 4,9; IC 95%: 2,2-10,9; p < 0,0001. Conclusiones: En pacientes adultos hospitalizados en plantas diferentes a UCI, hemos demostrado que la duración de la infusión de la NPT incrementa el riesgo de BAC. El incremento de riesgo es especialmente marcado, llegando a multiplicarse

  18. Entomofauna asociada a flores de berenjena y su papel en la producción de los frutos Insects associated with eggplant flowers and their role in fruit production

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    Julianne Milléo

    2011-06-01

    Full Text Available El papel de los insectos polinizadores despierta interés, principalmente, en la reproducción de plantas tales como la berenjena. Este trabajo de recolección de la entomofauna asociada a las flores de Solanum melongena tuvo como objetivos identificar posibles agentes polinizadores locales y analizar el beneficio de los insectos antófilos a esta planta. Las observaciones y la colecta de los insectos visitantes de las flores fueron realizadas en febrero de 2008, entre las 7:00 y 17:15 horas, cada 45 minutos y en un área de 27 m². El experimento para el análisis y la comparación entre autofecundación espontánea y polinización por medio de agentes bióticos fue realizado en el mismo sitio, de febrero a marzo de 2009. Fueron colectados 631 insectos que visitaban las flores de berenjena, se destacaron los coleópteros de los géneros Colaspis Fabricius, Astylus Laporte, Harmonia Mulsant, Epitrix Foudras y Diabrotica Chevrolat; y los himenópteros del género Bombus Latreille. El pico de visitación en Solanum melongena ocurrió entre las 9:00 y 11:00 horas y corresponde al 36% del muestreo. De las flores sometidas al test de autofecundación espontánea, el 39% formaron frutos, mientras que apenas el 11% de las flores emasculadas y expuestas al proceso de acción por medio de agentes bióticos fructificaron.The interest in the role of insect pollination is growing, mainly in the reproduction of plants of economic interest, such as the eggplant. This study about the entomofauna associated with flowers of Solanum melongena has as objectives to identify possible pollinators' agents and to analyze the benefit of the anthophile insects to this plant. The observations and the survey of the flower visitors' insects were made in February 2008, between 7:00 am and 5:15 pm, every 45 minutes, in an area of 27 m². The experiment for analysis and comparison between spontaneous self pollination and by biological agents was made at the same place, from

  19. Incidencia de bacteriemia asociada a catéter en niños hospitalizados que reciben nutrición parenteral Blood-stream catheter related infection in inpatient children receiving parenteral nutrition

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    E. Vaquero Sosa

    2011-02-01

    Full Text Available Las infecciones relacionadas con el catéter son la complicación más grave en los pacientes portadores de un catéter venoso central. Se considera que la nutrición parenteral (NP constituye un factor de riesgo de desarrollar una infección relacionada con el catéter (IRCat. Material y métodos: para conocer la tasa de infección y poder establecer estrategias de prevención de la infección nosocomial, se revisaron todas las historias de los 120 pacientes que recibieron NP a lo largo de 2008. Todas las historias de los pacientes con un episodio fiebre y hemocultivo positivo fueron consideradas. La tasa de infección se definió como número de episodios por cada 1000 días de NP. Resultados: Se obtuvieron 48 hemocultivos positivos. La tasa global de bacteriemia asociada a catéter fue de 37,8/1000 días de NP. La incidencia fue significativamente mayor en lactantes menores de 2 años de edad. Los gérmenes que se encontraron con mayor frecuencia fueron Estafilococo coagulasa negativo (56,8%, seguidos de bacilos Gram (20,8%, Staph aureus (12,5% y los hongos (12,5%. No encontramos diferencias en la tasa de infección cuando ajustamos por la enfermedad de base o la duración de la NP. Conclusiones: La tasa de infección en niños con NP en el hospital es considerablemente elevada. La NP parece constituir un factor de riesgo de desarrollar IRCat. Es necesario establecer políticas adecuadas y continuadas para conseguir disminuir la tasa de infección nosocomial.Blood-stream catheter related infection is the most severe complication in patients carrying a central venous catheter. Parenteral nutrition (PN use seems to be a risk factor for developing a catheter-related infection (CRI. Material & methods: In order to know the incidence of CRI in children to further implement policies to reduce nosocomial infection, we review all charts of children (1 month to 17 years who received parenteral nutrition while in hospital. All episodes of fever

  20. Diversidad zoológica asociada a un silvopastoreo leucaena-guinea con diferentes edades de establecimiento Zoological diversity associated to a silvopastural system leucaena-guinea grass with different establishment times

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    Jatnel Alonso Lazo

    2007-12-01

    Full Text Available El objetivo de este trabajo fue evaluar la diversidad zoológica asociada a un silvopastoreo con leucaena-guinea, por medio de la caracterización de la composición y estructura de las aves, insectos y la macrofauna del suelo, en cuatro edades de establecimiento (3, 4, 5 y 6 años de explotación. Con las especies registradas en cada uno de estos grupos zoológicos, se calcularon los índices ecológicos: número de individuos, riqueza, diversidad y abundancia de especies, en diferentes edades del sistema. En todos los grupos, se apreció el aumento significativo en la riqueza de especies y en el índice de diversidad biológica de Shannon, en la medida que se desarrolló el sistema. Se observó incremento en la abundancia de insectos biorreguladores y, en relación con las aves, el horario de muestreo no mostró interacción con los distintos años de siembra. La macrofauna se incrementó, observándose dominancia de anélidos al 6º y 7º año de explotación, caracterizado por Polyferetrina elongata y Oligochaeta elegans. El desarrollo del silvopastoreo leucaena-guinea logra sistemas productivos pecuarios que aumentan la producción de biomasa y de otros componentes biológicos y contribuir para crear un sistema sostenible y compatible con el ambiente.The aim of this work was to evaluate the associated zoological diversity of a silvopastural system leucaena-guinea grass, by characterizing the composition and structures of the birds, insects and the macrofauna of the soil, in four establishment times of the silvopastural systems (3, 4, 5 and 6 years of exploitation. For the species recorded in each zoological group, the following ecological indices were determined: number of individuals, richness, diversity and abundance of species, in each establishment times of the system. A significant increase, in all the zoological groups, was observed for the richness of species and for the index of biological diversity of Shannon, as the system

  1. EL ENTRENAMIENTO DE FUERZA DEL TREN SUPERIOR CON CARGAS ASOCIADAS A LA MÁXIMA POTENCIA INDIVIDUAL: ANÁLISIS DE LOS EFECTOS AGUDOS SOBRE LA POTENCIA MECÁNICA

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    E. Iglesias

    2010-09-01

    Full Text Available

     

    RESUMEN

    El propósito del presente trabajo fue valorar el efecto agudo del entrenamiento de fuerza explosiva sobre el rendimiento mecánico. De una muestra de 9 sujetos masculinos se obtuvo la máxima carga movilizable en una sola repetición concéntrica (1RM del ejercicio press banca y la resistencia correspondiente al máximo nivel de potencia. Posteriormente se desarrollaron dos sesiones consistentes en 7 series de 3 repeticiones con las cargas asociadas a la máxima potencia individual. Previo a la primera serie de entrenamiento e inmediatamente posterior a la última se obtuvieron los niveles de potencia desarrollados tanto con el 90% 1RM como con la magnitud manejada en la sesión. Finalmente se llevó a cabo una evaluación postest. El ANOVA para medidas repetidas reflejó diferencias significativas al 90% 1RM (p<0.05 aunque los contrastes de los valores previos y posteriores a cada una de las sesiones no alcanzó significación estadística (p>0.005 en ninguna de las variables. No se detectó asociación estadísticamente significativa entre las modificaciones agudas del rendimiento y el nivel de fuerza de los sujetos. Sin embargo, si se halló correlación significativa (p<0.05 entre éste parámetro en el postest y el porcentaje de 1RM que suponía la carga de máxima potencia en la última medición.
    PALABRAS CLAVE: fuerza, cargas de contraste, press banca, potencia.

     

    ABSTRACT

    The purpose of this study was to measure the acute effect of two explosive strength sessions on mechanical performance. In order to do that, 1 repetition maximum and maximum power load were obtained in 9 men. The experimental procedure begun five days after and it involved two training sessions. 7 bouts of

  2. Sexually transmitted infections associated with vulvovaginal symptoms in adolescents denying sexual activity Infecciones de transmisión sexual asociadas a síntomas vulvovaginales en adolescentes que niegan vida sexual activa

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    Elizabeth Velarde-Jurado

    2003-01-01

    Full Text Available OBJECTIVE: To identify clinical, laboratory and ultrasonographic evidence of a probable sexually transmitted infection associated with vulvovaginal symptoms in adolescents denying sexual activity. MATERIAL AND METHODS: The medical records of female adolescents, aged 10-18 years were reviewed. These women received first-time medical care for vulvovaginitis, between 1995 and 1999 at Hospital Infantil de México Federico Gómez, (Children's Hospital. Comparisons between groups were performed, as appropriate, by the unpaired Student's t-test, the Z test or the chi-square test; statistically significant differences were set at a two-tailed pOBJETIVO: Identificar datos clínicos, de laboratorio y ultrasonográficos que permitan el diagnóstico de una infección de transmisión sexual asociada a síntomas vulvovaginales en las pacientes adolescentes que niegan vida sexual activa. MATERIAL Y MÉTODOS: Se revisaron los expedientes de las adolescentes de 10 a 18 años de edad que requirieron atención médica de primera vez por vulvovaginitis entre 1995 y 1999 en el Hospital Infantil de México Federico Gómez. Las comparaciones entre grupos se llevaron a cabo con la prueba t de Student, la prueba de Z, o la de ji-cuadrada. Se utilizó un valor de p<0.05 para establecer diferencias estadísticamente significativas. Se calcularon razones de momios con intervalos de confianza de 95%. RESULTADOS: De 258 adolescentes, en 53 (20.5% se identificó un microrganismo de transmisión sexual y 52 de ellas negaron tener vida sexual activa. No hubo diferencias estadísticas entre los dos grupos de adolescentes en cuanto a la edad, los años de estudio, el nivel socioeconómico, la maduración sexual y la presencia de menarquia. El dolor abdominal en los cuadrantes inferiores, la coloración anormal de la secreción vaginal, un cultivo urinario positivo y un estudio ultrasonográfico abdominal compatible con enfermedad pélvica inflamatoria estuvieron asociados con

  3. [The Role of Ombrophilic Dissipotrophic Bacteria in Wood Decomposition].

    Science.gov (United States)

    Zaichikova, M V; Berestovskaya, Y Y; Vasil'eva, L V

    2016-01-01

    The summarized experimental data on ombrophilic bacteria isolated from dystrophic waters formed by a mycobacterial community during the process of spruce wood decomposition are presented. It was demonstrated that the ombrophilic microbial community was characterized by wide phylogenetic diversity at the initial stage of spruce wood decomposition by xylotrophic fungi under low mineralization conditions. It was noted that bacteria were able to grow under acidic and ultrafresh conditions and most of them were referred to oligotrophs. It was determined that all isolated ombrophilic bacteria divided into three groups depending on the substrate specifity: saccharolytic, acidotrophic bacteria, and bacteria, which used C1-compounds as the substrate. The position of the ombrophilic bacteria in the trophic chain was determined.

  4. THE AVAILABILITY OF Mytilus galloprovincialis FOR MONITORING ENTERIC BACTERIA

    Directory of Open Access Journals (Sweden)

    Nüket SĐVRĐ

    2012-01-01

    Full Text Available In this study, the usage of Mediterranean Mussel (Mytilus galloprovincialis Lamarck, 1819 as monitoring organism on enteric bacteria concentrations in heavily polluted marine environments and its use possibilities as water quality improving tool were investigated. The ability of the Mediterranean Mussel to accumulate and purge fecal coliform bacteria investigated in laboratory experiments. First, increase on bacteria concentration was observed on 1,5th hour and sharp decrease rate lasted until 10th hours after that period slow but steady declining bacteria concentration rate was observed and beginning bacteria concentration rate was reached within next 30- 50 hours. Time dependent bacteria concentration reduction has found statistically significant at p<0.001 (r-sq = 0.81. The investigation has also revealed that mussel farming could be established in the over polluted area which is the case only in the different discharge points in the sea.

  5. Phototrophic bacteria and their role in the biogeochemical sulfur cycle

    Science.gov (United States)

    Trueper, H. G.

    1985-01-01

    An essential step that cannot be bypassed in the biogeochemical cycle of sulfur today is dissimilatory sulfate reduction by anaerobic bacteria. The enormous amounts of sulfides produced by these are oxidized again either anaerobically by phototrophic bacteria or aerobically by thiobacilli and large chemotrophic bacteria (Beggiatoa, Thiovulum, etc.). Phototrophic bacteria use sulfide, sulfur, thiosulfate, and sulfite as electron donors for photosynthesis. The most obvious intermediate in their oxidative sulfur metabolism is a long chain polysulfide that appears as so called sulfur globules either inside (Chromatiaceae) or outside (Ectothiorhodospiraceae, Chlorobiaceae, and some of the Rhodospirillaceae) the cells. The assimilation of sulfur compounds in phototrophic bacteria is in principle identical with that of nonphototrophic bacteria. However, the Chlorobiaceae and some of the Chromatiaceae and Rhodospirillaceae, unable to reduce sulfate, rely upon reduced sulfur for biosynthetic purposes.

  6. Efecto de la aplicación de roca fosfórica y la inoculación con bacterias solubilizadoras de fosfatos sobre el crecimiento del ají (Capsicum annum L.

    Directory of Open Access Journals (Sweden)

    Carlos Patiño Torres

    2014-04-01

    Full Text Available La utilización de roca fosfórica para la fertilización de los cultivos tropicales es una práctica eficaz y sostenible,cuyos efectos positivos sobre las plantas pueden aumentarse a través de su inoculación con microorganismos promotores del crecimiento vegetal. Para evaluar esta hipótesis, se estudió en invernadero el efecto de la fertilización con roca fosfórica en plantas de ají (Capsicum annum L. variedad Cayena, inoculadas y sin inocular, con dos aislamientos bacterianos solubilizadores de fosfato (Burkholderia ambifaria y B. lata, utilizando como sustrato un suelo ácido altamente deficiente en fósforo, sobre variables asociadas con el crecimiento de las plantas. Los ensayos mostraron efecto significativo de la roca fosfórica (RF sola y/o en conjunto con los aislamientos inoculados. La bioinoculación permitió disminuir la RF, a la mitad (12 g/unidad experimental de la dosis más adecuada, sin afectar estadísticamente la media de las variables analizadas, igualmente, los contenidos de fósforo (15P en los tejidos de las plantas inoculadas con las bacterias fueron superiores comparados con el de aquellas no inoculadas.

  7. Bacteria in Cancer Therapy: Renaissance of an Old Concept

    OpenAIRE

    Sebastian Felgner; Dino Kocijancic; Michael Frahm; Siegfried Weiss

    2016-01-01

    The rising incidence of cancer cases worldwide generates an urgent need of novel treatment options. Applying bacteria may represent a valuable therapeutic variant that is intensively investigated nowadays. Interestingly, the idea to apply bacteria wittingly or unwittingly dates back to ancient times and was revived in the 19th century mainly by the pioneer William Coley. This review summarizes and compares the results of the past 150 years in bacteria mediated tumor therapy from preclinical t...

  8. Prevalence of Tetracycline Resistance Genes in Oral Bacteria

    OpenAIRE

    Villedieu, A.; Diaz-Torres, M. L.; Hunt, N; McNab, R; Spratt, D. A.; Wilson, M.; Mullany, P.

    2003-01-01

    Tetracycline is a broad-spectrum antibiotic used in humans, animals, and aquaculture; therefore, many bacteria from different ecosystems are exposed to this antibiotic. In order to determine the genetic basis for resistance to tetracycline in bacteria from the oral cavity, saliva and dental plaque samples were obtained from 20 healthy adults who had not taken antibiotics during the previous 3 months. The samples were screened for the presence of bacteria resistant to tetracycline, and the tet...

  9. Isolation of pathogenic bacteria from hospital staff apparel in Nigeria

    OpenAIRE

    Orji, MU; Mbata, TI; Kalu, OU

    2005-01-01

    A survey of bacteria contamination of hospital staff apparel in use in Anambra State, Nigeria, was carried out to determine the extent of contamination by clinically important bacteria. Of a total of 125 swab samples of hospital staff apparel, 72 (58%) showed bacterial contamination including 32 (70%) of 46 samples from hand gloves, 28 of 45 (62%) samples from protective gowns, and 12 of 34 (35%) samples from face-shields. The potentially pathogenic bacteria isolated were Salmonella spp, Prot...

  10. The identification and biogeochemical interpretation of fossil magnetotactic bacteria

    OpenAIRE

    Kopp, Robert E.; Kirschvink, Joseph L

    2008-01-01

    Magnetotactic bacteria, which most commonly live within the oxic-anoxic transition zone (OATZ) of aquatic environments, produce intracellular crystals of magnetic minerals, specifically magnetite or greigite. The crystals cause the bacteria to orient themselves passively with respect to the geomagnetic field and thereby facilitate the bacteria’s search for optimal conditions within the sharp chemical gradients of the OATZ. The bacteria may also gain energy from the redox cycling of their ...

  11. Bacterias, fuente de energía para el futuro

    Directory of Open Access Journals (Sweden)

    Alba Ayde Romero Mejía

    2012-06-01

    Full Text Available This paper presents a family of bacteria called Geobacter that have the ability to produce power as a renewable source in a microbial fuel cell. These bacteria can completely oxidize organic compounds using different elements or substances as electron acceptors. The paper addresses key features of the bacteria, the mechanisms used to harness the electricity generated and an approximation of the system required to become a competitive source of renewable energy. The results show a comparative analysis of sources of conventional and unconventional energy with respect to the Geobacter family of bacteria.

  12. Predatory bacteria are nontoxic to the rabbit ocular surface

    Science.gov (United States)

    Romanowski, Eric G.; Stella, Nicholas A.; Brothers, Kimberly M.; Yates, Kathleen A.; Funderburgh, Martha L.; Funderburgh, James L.; Gupta, Shilpi; Dharani, Sonal; Kadouri, Daniel E.; Shanks, Robert M. Q.

    2016-01-01

    Given the increasing emergence of antimicrobial resistant microbes and the near absent development of new antibiotic classes, innovative new therapeutic approaches to address this global problem are necessary. The use of predatory bacteria, bacteria that prey upon other bacteria, is gaining interest as an “out of the box” therapeutic treatment for multidrug resistant pathogenic bacterial infections. Before a new antimicrobial agent is used to treat infections, it must be tested for safety. The goal of this study was to test the tolerability of bacteria on the ocular surface using in vitro and in vivo models. Predatory bacteria Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus were found to be non-toxic to human corneal stromal keratocytes in vitro; however, they did induce production of the proinflammatory chemokine IL-8 but not IL-1β. Predatory bacteria did not induce inflammation on the ocular surface of rabbit eyes, with and without corneal epithelial abrasions. Unlike a standard of care antibiotic vancomycin, predatory bacteria did not inhibit corneal epithelial wound healing or increase clinical inflammatory signs in vivo. Together these data support the safety of predatory bacteria on the ocular surface, but future studies are warranted regarding the use predatory bacteria in deeper tissues of the eye. PMID:27527833

  13. Isolation and identification of marine fish tumour (odontoma) associated bacteria

    Institute of Scientific and Technical Information of China (English)

    Ramalingam Vijayakumar; Kuzhanthaivel Raja; Vijayapoopathi Singaravel; Ayyaru Gopalakrishnan

    2015-01-01

    Objective: To identify fish tumour associated bacteria. Methods: The marine fish Sphyraena jello with odontoma was collected from in Tamil Nadu (Southeast India), and tumour associated bacteria were isolated. Then the isolated bacteria were identified based on molecular characters. Results: A total of 4 different bacterial species were isolated from tumour tissue. The bacterial species were Bacillus sp., Pontibacter sp., Burkholderia sp. and Macrococcus sp., and the sequences were submitted in DNA Data Bank of Japan with accession numbers of AB859240, AB859241, AB859242 and AB859243 respectively. Conclusions: Four different bacterial species were isolated from Sphyraena jello, but the role of bacteria within tumour needs to be further investigated.

  14. Quantification and qualification of bacteria trapped in chewed gum.

    Directory of Open Access Journals (Sweden)

    Stefan W Wessel

    Full Text Available Chewing of gum contributes to the maintenance of oral health. Many oral diseases, including caries and periodontal disease, are caused by bacteria. However, it is unknown whether chewing of gum can remove bacteria from the oral cavity. Here, we hypothesize that chewing of gum can trap bacteria and remove them from the oral cavity. To test this hypothesis, we developed two methods to quantify numbers of bacteria trapped in chewed gum. In the first method, known numbers of bacteria were finger-chewed into gum and chewed gums were molded to standard dimensions, sonicated and plated to determine numbers of colony-forming-units incorporated, yielding calibration curves of colony-forming-units retrieved versus finger-chewed in. In a second method, calibration curves were created by finger-chewing known numbers of bacteria into gum and subsequently dissolving the gum in a mixture of chloroform and tris-ethylenediaminetetraacetic-acid (TE-buffer. The TE-buffer was analyzed using quantitative Polymerase-Chain-Reaction (qPCR, yielding calibration curves of total numbers of bacteria versus finger-chewed in. Next, five volunteers were requested to chew gum up to 10 min after which numbers of colony-forming-units and total numbers of bacteria trapped in chewed gum were determined using the above methods. The qPCR method, involving both dead and live bacteria yielded higher numbers of retrieved bacteria than plating, involving only viable bacteria. Numbers of trapped bacteria were maximal during initial chewing after which a slow decrease over time up to 10 min was observed. Around 10(8 bacteria were detected per gum piece depending on the method and gum considered. The number of species trapped in chewed gum increased with chewing time. Trapped bacteria were clearly visualized in chewed gum using scanning-electron-microscopy. Summarizing, using novel methods to quantify and qualify oral bacteria trapped in chewed gum, the hypothesis is confirmed that chewing

  15. Liquid-nitrogen cryopreservation of three kinds of autotrophicbioleaching bacteria

    Institute of Scientific and Technical Information of China (English)

    WU Xue-ling; XIN Xiao-hong; JIANG Ying; LIANG Ren-xing; YUAN Peng; FANG Cheng-xiang

    2008-01-01

    Three kinds of autotrophic bioleaching bacteria strains,including mesophilic and acidophilic ferrous ion-oxidizing bacteria Acidithiobacillus ferrooxidans (A.ferrooxidans),mesophilic and acidophilic sulfur-oxidizing bacteria Acidithiobacillus thiooxidans (A.thiooxidans),and moderately thermophilic sulfur-oxidizing bacteria Acidianus brierleyi,were cryopreserved in liquid nitrogen and their ferrous ion- or sulfur-oxidizing activities were investigated and compared with the original ones.The results revealed that ferrous ion/sulfur oxidation activities of the strains were almost equal before and after cryopreservation.Glycerin was used as cryoprotective agent.In conclusion,liquid-nitrogen cryopreservation is a simple and effective method for autotrophic bioleaching microorganisms.

  16. Identification of bacteria in scuba divers' rinse tanks.

    Science.gov (United States)

    Washburn, Brian K; Levin, Andrew E; Hennessy, Kristen; Miller, Michael R

    2010-01-01

    Scuba divers typically rinse equipment in communal tanks. Studies show these tanks are contaminated with bacteria, but the types of bacteria have not been studied. We sought to identify bacteria in rinse tanks at a dive facility at San Pedro, Belize, to determine the origin of the bacteria and determine whether the bacteria represented potential threats to human health. The identity of bacteria was investigated using reverse line blot (RLB) assays based on 28 different rDNA probes designed to detect known pathogens of sepsis, as well as by sequencing 23S rDNA from isolates and performing VITEK identification of several isolates. Based on the identities of bacteria in divers' rinse tanks, many likely originate from the ocean, and others likely originate from the divers themselves. None of the bacteria identified would be considered overt human pathogens. However, some of the bacteria found in the tanks are known to be associated with unsanitary conditions and can cause opportunistic infections, which may pose health problems to some individuals. Rinsing scuba equipment in communal tanks has the potential to transmit disease among some divers. Equipment, especially regulators and masks, should be rinsed/cleaned individually and not be placed in communal tanks.

  17. Control of indigenous pathogenic bacteria in seafood

    DEFF Research Database (Denmark)

    Huss, Hans Henrik

    1997-01-01

    The pathogenic bacteria indigenous to the aquatic and general environment are listed. Their distribution in nature, prevalence in seafood and the possibilities for growth of these organisms in various types of products are outlined These data, combined with what is known regarding the epidemiology...... of disease, are used to place the various seafood products in risk categories and to identify areas of concern. It is concluded that the presence of pathogens in molluscs and the growth of Listeria monocytogenes in lightly preserved fish products are hazards which are presently not under control. In order...... to prevent growth and toxin production by Clostridium botulinum when products are stored at abuse temperature, it is recommended that additional barriers to growth are included in lightly preserved (e.g. cold smoked salmon) and low-heat treated (e.g REPFEDS) products. It is finally pointed out...

  18. Magnetotactic bacteria. Promising biosorbents for heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Wei; Zhang, Yanzong; Ding, Xiaohui; Liu, Yan; Shen, Fei; Zhang, Xiaohong; Deng, Shihuai; Xiao, Hong; Yang, Gang; Peng, Hong [Sichuan Agricultural Univ., Chengdu (China). Provincial Key Lab. of Agricultural Environmental Engineering

    2012-09-15

    Magnetotactic bacteria (MTB), which can orient and migrate along a magnetic line of force due to intracellular nanosized magnetosomes, have been a subject of research in the medical field, in dating environmental changes, and in environmental remediation. This paper reviews the recent development of MTB as biosorbents for heavy metals. Ultrastructures and taxis of MTB are investigated. Adsorptions in systems of unitary and binary ions are highlighted, as well as adsorption conditions (temperature, pH value, biomass concentration, and pretreatments). The separation and desorption of MTB in magnetic separators are also discussed. A green method to produce metal nanoparticles is provided, and an energy-efficient way to recover precious metals is put forward during biosorption. (orig.)

  19. Degradation of multiwall carbon nanotubes by bacteria

    International Nuclear Information System (INIS)

    Understanding the environmental transformation of multiwall carbon nanotubes (MWCNTs) is important to their life cycle assessment and potential environmental impacts. We report that a bacterial community is capable of degrading 14C-labeled MWCNTs into 14CO2 in the presence of an external carbon source via co-metabolism. Multiple intermediate products were detected, and genotypic characterization revealed three possible microbial degraders: Burkholderia kururiensis, Delftia acidovorans, and Stenotrophomonas maltophilia. This result suggests that microbe/MWCNTs interaction may impact the long-term fate of MWCNTs. Highlights: •Mineralization of MWCNTs by a bacterial community was observed. •The mineralization required an external carbon source. •Multiple intermediate products were identified in the MWCNT degrading culture. •Three bacterial species were found likely responsible for MWCNT degradation. -- The 14C-labeled multiwall carbon nanotubes can be degraded to 14CO2 and other byproducts by a bacteria community under natural conditions

  20. Detection of bacteria with bioluminescent reporter bacteriophage.

    Science.gov (United States)

    Klumpp, Jochen; Loessner, Martin J

    2014-01-01

    Bacteriophages are viruses that exclusively infect bacteria. They are ideally suited for the development of highly specific diagnostic assay systems. Bioluminescent reporter bacteriophages are designed and constructed by integration of a luciferase gene in the virus genome. Relying on the host specificity of the phage, the system enables rapid, sensitive, and specific detection of bacterial pathogens. A bioluminescent reporter phage assay is superior to any other molecular detection method, because gene expression and light emission are dependent on an active metabolism of the bacterial cell, and only viable cells will yield a signal. In this chapter we introduce the concept of creating reporter phages, discuss their advantages and disadvantages, and illustrate the advances made in developing such systems for different Gram-negative and Gram-positive pathogens. The application of bioluminescent reporter phages for the detection of foodborne pathogens is emphasized.

  1. [Antimicrobial susceptibility testing of anaerobic bacteria].

    Science.gov (United States)

    García-Sánchez, José E; García-Sánchez, Enrique; García-García, María Inmaculada

    2014-02-01

    The anaerobic bacteria resistance to antibiotics is increasing, and even has appeared against the most active of those, like metronidazol and carbapenems. This fact forces to make and periodical sensibility tests -at least in the most aggressive and virulent species, in cases that they are isolated from life locations and in the absence of therapeutic response- to check the local sensibility and to establish suitable empiric therapies, all based on multicentric studies carried out in order to this or well to check the activity of new antibiotics. For the laboratory routine, the easiest sensibility method is the E-test/MIC evaluator. Another alternative is microdilution, that's only normalized for Bacteroides. There are preliminary facts that allow the use of disc diffusion method in some species of Bacteroides and Clostridium. For the temporal and multicentric studies, the procedure is dilution in agar plate, the reference method.

  2. Phosphate Solubilizing Bacteria Adaptive to Vinasse

    Directory of Open Access Journals (Sweden)

    Kahar Muzakhar

    2015-06-01

    Full Text Available Microorganisms identified as phosphate solubilizing bacteria (PSB adaptive to vinasse were successfully screened from sugarcane soil from an agriculatural estate in Jatiroto. By conducting a screening on Pikovskaya’s agar medium (PAM, we found that five different isolates were detected as PSB (pvk-5a, pvk-5b, pvk-6b, pvk-7a, and pvk-8a. Of the five isolates only three could be grown and were found to be adaptive to vinasse based medium without any nutrients added (pvk-5a, pvk-5b and pvk-7a. The three isolates were characterized as coccus and Gram negative with no endospores detected. We suggest that these three isolates can be used as biofertilizer agent to support organic farming.

  3. Isolation and Identification of Nitrite- oxidizing Bacteria

    Institute of Scientific and Technical Information of China (English)

    Yulong; CHEN; Wenyong; TAN; Da; YANG

    2015-01-01

    In order to select the strain that can degrade nitrite,we use the screening plate with nitrite as the sole nitrogen source to select the strain with ability to degrade nitrite,and get a strain with nitrite degrading capacity from the silt of shrimp farming pond in Hepu City,Guangxi Zhuang Autonomous Region. By identifying the strain from colony morphology,physiological and biochemical characteristics and 16 S r RNA sequence,we finally get a bacteria strain that can degrade nitrite,and this strain can grow well on the culture medium with nitrite concentration of 2 g / L. Based on morphology,nitrogen source requirements and evolutionary tree analysis of the above 16 S r RNA sequence,it is found that this strain belongs to Pannonibacter phragmitetus. According to the screening location,it is named HPPP007 strain.

  4. Bacteria,inflammation,and colon cancer

    Institute of Scientific and Technical Information of China (English)

    Liying Yang; Zhiheng Pei

    2006-01-01

    Our relationship with the colonic bacterial flora has long been viewed as benign,but recent studies suggest that this symbiosis has risks as well as benefits.This relationship requires that the host not only provide a supportive environment for the symbiotic bacteria,but also actively maintain intact mechanisms for properly managing the physiologic stresses that are closely associated with the symbiont's essential survival functions.Failure to do so breaches the hostsymbiont contract,and can result in serious effects on the health of the host.Recent investigations that employ several knockout mouse models reveal the consequences of genetic deficiency in the host regarding these mechanisms,and the latent,pro-inflammatory,tumorigenic nature of normal bacterial flora.Further study of the interactions between normal bacterial flora and hosts could shed light on the etiologies and pathogenesis of inflammatory diseases and related cancers,with implications for human health.

  5. Exopolysaccharides from sourdough lactic acid bacteria.

    Science.gov (United States)

    Galle, Sandra; Arendt, Elke K

    2014-01-01

    The use of sourdough improves the quality and increases the shelf life of bread. The positive effects are associated with metabolites produced by lactic acid bacteria (LAB) during sourdough fermentation, including organic acids, exopolysaccharides (EPS), and enzymes. EPS formed during sourdough fermentation by glycansucrase activity from sucrose influence the viscoelastic properties of the dough and beneficially affect the texture and shelf life (in particular, starch retrogradation) of bread. Accordingly, EPS have the potential to replace hydrocolloids currently used as bread improvers and meet so the consumer demands for a reduced use of food additives. In this review, the current knowledge about the functional aspects of EPS formation by sourdough LAB especially in baking applications is summarized.

  6. Magnetotactic bacteria: nanodrivers of the future.

    Science.gov (United States)

    Mathuriya, Abhilasha Singh

    2016-10-01

    Magnetotactic bacteria (MTB) represent a heterogeneous group of Gram-negative aquatic prokaryotes with a broad range of morphological types, including vibrioid, coccoid, rod and spirillum. MTBs possess the virtuosity to passively align and actively swim along the magnetic field. Magnetosomes are the trademark nano-ranged intracellular structures of MTB, which comprise magnetic iron-bearing inorganic crystals enveloped by an organic membrane, and are dedicated organelles for their magnetotactic lifestyle. Magnetosomes endue high and even dispersion in aqueous solutions compared with artificial magnetites, claiming them as paragon nanomaterials. MTB and magnetosomes offer high technological potential in modern science, technology and medicines. This review focuses on the applicability of MTB and magnetosomes in various areas of modern benefits. PMID:26287367

  7. [Travellers and multi-drug resistance bacteria].

    Science.gov (United States)

    Takeshita, Nozomi

    2012-02-01

    The number of international travellers has increased. There is enormous diversity in medical backgrounds, purposes of travel, and travelling styles among travellers. Travellers are hospitalized abroad because of exotic and common diseases via medical tourism. This is one way of transporting and importing human bacteria between countries, including multi-drug resistant organisms. In developing countries, the antimicrobial resistance in Shigella sp. and Salmonella sp. have been a problem, because of this trend, the first choice of antibiotics has changed in some countries. Community acquired infections as well as hospital acquired infections with MRSA, multi-drug resistance (MDR) Pseudomonas aeruginosa, and ESBL have been a problem. This review will discuss the risk of MDR bacterial infectious diseases for travellers. PMID:22413540

  8. Physical mode of bacteria and virus coevolution

    Science.gov (United States)

    Han, Pu; Niestemski, Liang; Deem, Michael

    2013-03-01

    Single-cell hosts such as bacteria or archaea possess an adaptive, heritable immune system that protects them from viral invasion. This system, known as the CRISPR-Cas system, allows the host to recognize and incorporate short foreign DNA or RNA sequences from viruses or plasmids. The sequences form what are called ``spacers'' in the CRISPR. Spacers in the CRISPR loci provide a record of the host and predator coevolution history. We develop a physical model to study the dynamics of this coevolution due to immune pressure. Hosts and viruses reproduce, die, and evolve due to viral infection pressure, host immune pressure, and mutation. We will discuss the differing effects of point mutation and recombination on CRISPR evolution. We will also discuss the effect of different spacer deletion mechanisms. We will describe population structure of hosts and viruses, how spacer diversity depends on position within CRISPR, and match of the CRISPR spacers to the virus population.

  9. Dynamics of swimming bacteria at complex interfaces

    CERN Document Server

    Lopez, Diego

    2014-01-01

    Flagellated bacteria exploiting helical propulsion are known to swim along circular trajectories near surfaces. Fluid dynamics predicts this circular motion to be clockwise (CW) above a rigid surface (when viewed from inside the fluid) and counter-clockwise (CCW) below a free surface. Recent experimental investigations showed that complex physicochemical processes at the nearby surface could lead to a change in the direction of rotation, both at solid surfaces absorbing slip-inducing polymers and interfaces covered with surfactants. Motivated by these results, we use a far-field hydrodynamic model to predict the kinematics of swimming near three types of interfaces: clean fluid-fluid interface, slipping rigid wall, and a fluid interface covered by incompressible surfactants. Representing the helical swimmer by a superposition of hydrodynamic singularities, we first show that in all cases the surfaces reorient the swimmer parallel to the surface and attract it, both of which are a consequence of the Stokes dip...

  10. Uptake of plutonium by immobilized bacteria

    International Nuclear Information System (INIS)

    The use of plastic-immobilized bacteria as a system for the concentration of plutonium from aqueous media is investigated. Previous research is reviewed quantifying free cell bacterial concentration of plutonium from solution or suspension. Our research indicates that the species Pseudomonas aeruginosa can be induced to attach firmly to a polymer substrate, while retaining its ability to concentrate plutonium. Melt-blown, filamentous polypropylene is shown to foster cell embedment and uptake capabilities surpassing various other substrates. Oxygen plasma treatment, used to enhance polypropylene wettability, is found to increase the rate of cell embedment significantly. Both embedment and uptake phenomena are found to be dependent upon cell viability. Potential applications for the cell/polymer system are discussed

  11. Bacteria and bioremediation of marine oil spills

    International Nuclear Information System (INIS)

    Virtually all marine ecosystems harbor indigenous hydrocarbon-degrading bacteria. These hydrocarbon degraders comprise less than one percent of the bacterial community in unpolluted environments, but generally increase to one to ten percent following petroleum contamination. Various hydrocarbons are degraded by these microorganisms at different rates, so there is an evolution in the residual hydrocarbon mixture, and some hydrocarbons and asphaltic petroleum hydrocarbons remain undegraded. Fortunately, these persistent petroleum pollutants are, for the most part, insoluble or are bound to solids; hence they are not biologically available and therefore not toxic to marine organisms. Carbon dioxide, water, and cellular biomass produced by the microorganisms from the degradable hydrocarbons may be consumed by detrital feeders and comprise the end products of the natural biological degradation process. Bioremediation attempts to accelerate the natural hydrocarbon degradation rates by overcoming factors that limit bacterial hydrocarbon degrading activities

  12. Streptomyces bacteria as potential probiotics in aquaculture

    Directory of Open Access Journals (Sweden)

    Tan Loh eTeng Hern

    2016-02-01

    Full Text Available In response to the increased seafood demand from the ever-going human population, aquaculture has become the fastest growing animal food-producing sector. However, the indiscriminate use of antibiotics as a biological control agents for fish pathogens has led to the emergence of antibiotic resistance bacteria. Probiotics are defined as living microbial supplement that exert beneficial effects on hosts as well as improvement of environmental parameters. Probiotics have been proven to be effective in improving the growth, survival and health status of the aquatic livestock. This review aims to highlight the genus Streptomyces can be a good candidate for probiotics in aquaculture. Studies showed that the feed supplemented with Streptomyces could protect fish and shrimp from pathogens as well as increase the growth of the aquatic organisms. Furthermore, the limitations of Streptomyces as probiotics in aquaculture is also highlighted and solutions are discussed to these limitations.

  13. Stress Physiology of Lactic Acid Bacteria.

    Science.gov (United States)

    Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A; de Angelis, Maria; Gobbetti, Marco; Kleerebezem, Michiel; Lemos, José A; Linares, Daniel M; Ross, Paul; Stanton, Catherine; Turroni, Francesca; van Sinderen, Douwe; Varmanen, Pekka; Ventura, Marco; Zúñiga, Manuel; Tsakalidou, Effie; Kok, Jan

    2016-09-01

    Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance. PMID:27466284

  14. Stress Physiology of Lactic Acid Bacteria.

    Science.gov (United States)

    Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A; de Angelis, Maria; Gobbetti, Marco; Kleerebezem, Michiel; Lemos, José A; Linares, Daniel M; Ross, Paul; Stanton, Catherine; Turroni, Francesca; van Sinderen, Douwe; Varmanen, Pekka; Ventura, Marco; Zúñiga, Manuel; Tsakalidou, Effie; Kok, Jan

    2016-09-01

    Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance.

  15. Enumeration of petroleum hydrocarbon utilizing bacteria

    International Nuclear Information System (INIS)

    In-situ biological treatment is one among a number of emerging technologies that may be applied to the remediation of contaminated soils and groundwater. In 1985, a surface spill of 1,500 gallons of dielectric transformer oil at the Sandia National Laboratories (HERMES II facility) resulted in contamination of soil up to depths of 160 feet. The extent of contamination and site characteristics favored the application of in-situ bioremediation as a potential remedial technology. The purpose of this research was to enumerate indigenous microbial populations capable of degrading petroleum hydrocarbons. Microbial enumeration and characterization methods suitably adapted for hydrocarbon utilizing bacteria were used as an indicator of the presence of viable microbial consortia in excavated oil samples with hydrocarbon (TPH) concentrations ranging from 300 to 26,850 ppm. Microbial activity was quantified by direct and streak plating soil samples on silica gel media. Effects of toxicity and temperature were studied using batch cultures of hydrocarbon utilizing bacteria (selectively isolated in an enrichment medium), at temperatures of 20 and 35 C. It was concluded from this study that it is possible to isolate native microorganisms from contaminated soils from depths of 60 to 160 feet, and with oil concentration ranging from 300 to 26,850 ppm. About 62% of the microorganisms isolated form the contaminated soil were capable of using contaminant oil as a substrate for growth and metabolism under aerobic conditions. Growth rates were observed to be 50% higher for the highest contaminant concentration at 20 C. Resistance to toxicity to contaminant oil was also observed to be greater at 20 C than at 35 C

  16. Fewer Bacteria Adhere to Softer Hydrogels.

    Science.gov (United States)

    Kolewe, Kristopher W; Peyton, Shelly R; Schiffman, Jessica D

    2015-09-01

    Clinically, biofilm-associated infections commonly form on intravascular catheters and other hydrogel surfaces. The overuse of antibiotics to treat these infections has led to the spread of antibiotic resistance and underscores the importance of developing alternative strategies that delay the onset of biofilm formation. Previously, it has been reported that during surface contact, bacteria can detect surfaces through subtle changes in the function of their motors. However, how the stiffness of a polymer hydrogel influences the initial attachment of bacteria is unknown. Systematically, we investigated poly(ethylene glycol) dimethacrylate (PEGDMA) and agar hydrogels that were 20 times thicker than the cumulative size of bacterial cell appendages, as a function of Young's moduli. Soft (44.05-308.5 kPa), intermediate (1495-2877 kPa), and stiff (5152-6489 kPa) hydrogels were synthesized. Escherichia coli and Staphylococcus aureus attachment onto the hydrogels was analyzed using confocal microscopy after 2 and 24 h incubation periods. Independent of hydrogel chemistry and incubation time, E. coli and S. aureus attachment correlated positively to increasing hydrogel stiffness. For example, after a 24 h incubation period, there were 52 and 82% fewer E. coli adhered to soft PEGDMA hydrogels than to the intermediate and stiff PEGDMA hydrogels, respectively. A 62 and 79% reduction in the area coverage by the Gram-positive microbe S. aureus occurred after 24 h incubation on the soft versus intermediate and stiff PEGDMA hydrogels. We suggest that hydrogel stiffness is an easily tunable variable that could potentially be used synergistically with traditional antimicrobial strategies to reduce early bacterial adhesion and therefore the occurrence of biofilm-associated infections.

  17. Diversity of rumen bacteria in canadian cervids.

    Directory of Open Access Journals (Sweden)

    Robert J Gruninger

    Full Text Available Interest in the bacteria responsible for the breakdown of lignocellulosic feedstuffs within the rumen has increased due to their potential utility in industrial applications. To date, most studies have focused on bacteria from domesticated ruminants. We have expanded the knowledge of the microbial ecology of ruminants by examining the bacterial populations found in the rumen of non-domesticated ruminants found in Canada. Next-generation sequencing of 16S rDNA was employed to characterize the liquid and solid-associated bacterial communities in the rumen of elk (Cervus canadensis, and white tailed deer (Odocoileus virginianus. Despite variability in the microbial populations between animals, principle component and weighted UniFrac analysis indicated that bacterial communities in the rumen of elk and white tail deer are distinct. Populations clustered according to individual host animal and not the association with liquid or solid phase of the rumen contents. In all instances, Bacteroidetes and Firmicutes were the dominant bacterial phyla, although the relative abundance of these differed among ruminant species and between phases of rumen digesta, respectively. In the elk samples Bacteroidetes were more predominant in the liquid phase whereas Firmicutes was the most prevalent phyla in the solid digesta (P = 1×10(-5. There were also statistically significant differences in the abundance of OTUs classified as Fibrobacteres (P = 5×10(-3 and Spirochaetes (P = 3×10(-4 in the solid digesta of the elk samples. We identified a number of OTUs that were classified as phylotypes not previously observed in the rumen environment. Our results suggest that although the bacterial diversity in wild North American ruminants shows overall similarities to domesticated ruminants, we observed a number of OTUs not previously described. Previous studies primarily focusing on domesticated ruminants do not fully represent the microbial diversity of the

  18. Bacteria, some permanent tenants Space Station; Bacteria, unos inquilinos permanentes de la estacion espacial

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, B.

    2015-07-01

    Vacuum cleaners to operate the vacuum or rags with ethanol they are the products of cleaning of the astronauts. Is there tight spaces fully sterilized? It seems not, even in the Space Station International (ISS). When it comes to bacteria, they are able to travel more than 400 kilometers housed in costumes, bodies and interior of the astronauts themselves and settle in a enclosed space where-unlike in a {sup c}leanroom 'terrestre- the air is not recycled. A NASA study has found an abundance of bacteria 'opportunists' which, although harmless on Earth, they might derivasen cause infections in inflammations or skin irritations. Not forgetting those fungi that could damage or affect the infrastructure equipment space. (Author)

  19. Determination of Ammonia Oxidizing Bacteria and Nitrate Oxidizing Bacteria in Wastewater and Bioreactors

    Science.gov (United States)

    Francis, Somilez Asya

    2014-01-01

    The process of water purification has many different physical, chemical, and biological processes. One part of the biological process is the task of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB). Both play critical roles in the treatment of wastewater by oxidizing toxic compounds. The broad term is nitrification, a naturally occurring process that is carried out by AOB and NOB by using oxidation to convert ammonia to nitrite and nitrite to nitrate. To monitor this biological activity, bacterial staining was performed on wastewater contained in inoculum tanks and biofilm samples from bioreactors. Using microscopy and qPCR, the purpose of this experiment was to determine if the population of AOB and NOB in wastewater and membrane bioreactors changed depending on temperature and hibernation conditions to determine the optimal parameters for AOB/NOB culture to effectively clean wastewater.

  20. Identification of Bacteria and the Effect on Compressive Strength of Concrete

    OpenAIRE

    Anneza L. H.; Irwan J. M.; Othman N.; Alshalif A. Faisal

    2016-01-01

    This paper presents the species of bacteria used in this study as well as the effect of the bacteria on compressive strength of bioconcrete. Bioconcrete is not only more environmentally friendly but it is easy to procure. The objective of this research is to identify the ureolytic bacteria and sulphate reduction bacteria that have been isolated and further use the bacteria in concrete to determine the effect of bacteria on compressive strength. Identification of bacteria is conducted through ...