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Sample records for bacterias sulfato-reductoras asociadas

  1. Uso de bacterias sulfato-reductoras inmovilizadas para la precipitación de metales pesados

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    Vicente, Mariana Soledad

    2006-01-01

    Los objetivos de la tesis son: utilizar bacterias sulfato-reductoras para la precipitación de metales pesados; caracterizar el crecimiento de bacterias del género Desulfovibrio en distintas condiciones de cultivo; caracterizar la precipitación de iones metálicos por bacterias del género Desulfovibrio en cultivos batch; caracterizar el crecimiento de bacterias del género Desulfovibrio inmovilizadas sobre diferentes soportes inerte; caracterizar la precipitación de iones metálicos con bacterias...

  2. 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...

  3. 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...

  4. 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

  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. 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.

  7. 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

  8. 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

  9. 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.

  10. 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.

  11. “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 ...

  12. Superficies asociadas a nudos

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    Restrepo Mazo, Laura

    2010-01-01

    El estudio de las superficies asociadas a nudos ha sido muy importante en la teoría clásica de nudos, pues de ellas se derivan invariantes y propiedades que han permitido estudiar la clasificación y la existencia de los nudos y enlaces. En este trabajo se estudian las superficies asociadas nudos clásicos en general, interpretando algunos invariantes de nudos y enlaces provenientes de ellas. Se presenta el algoritmo de Killian Michael O’Brien para calcular una matriz de Seifert de un nudo, usa...

  13. 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 ...

  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; 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...

  15. 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.

  16. Poblaciones bacterianas utilizadoras de hidrógeno presentes en el tracto gastrointestinal del avestruz (Struthio camelus Var. Domesticus

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    J. M. Miramontes-Carrillo

    2008-01-01

    Full Text Available Tres grupos de bacterias compiten por hidrógeno en diferentes ecosistemas anaerobios, y junto con CO 2 , producen metano, sulfuro dehidrógeno y acetato. Estas reacciones representan ganancia de energía al animal. Motivo por el cual, el presente trabajo pretende evaluar la presencia y tamaño de poblaciones de bacterias utilizadoras de hidrógeno en el tracto gastrointestinaldel avestruz. Para ello se utilizaron medios AC11 para acetogénicas, Potgate para sulfato-reductoras y Fosfato buffer para metanogénicas. Las poblaciones se determinaron por el método del número más probable (NMP. El diseño fue completamente al azar, con arreglo factorial, A = porciones del tracto digestivo y B = microorganismo. El NMP, de acetogénicas y metanogénicas fue cero. Las bacterias sulfato-reductoras están presentes en todo el tracto gastrointestinal. Las poblaciones fueron 544.00; 532.00; 157.20; 155.32 y 76.48 x 10/ 6 para el intestino grueso, ciegos, intestino delgado, proventrículo y ventrículo, respectivamente. Los resultados confirman presencia y predominio de las sulfato-reductoras en todas las porciones del tracto gastrointestinal del Struthio camelus. La producción de AGV en el tracto gastrointestinal del avestruz, es producto del metabolismo y reutilización del hidrógeno por bacterias sulfato-reductoras.

  17. 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.

  18. 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

  19. Estudio de la teoría de despolarización catódica con permeación de hidrógeno y la bacteria Desulfovibrio desulfuricans

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    Pérez, O.

    2003-12-01

    Full Text Available A Desulfovibrio desulfuricans ssp. desulfuricans (SRB was used to study the permeation of hydrogen, using a Devanaran and Stachurski cell and a palladium sheet. The aim was to evaluate cathodic depolarization as a Sulfate-Reducing Bacteria action mechanism in Microbiologically Induced Corrosion. The permeation tests were run with and without cathodic polarization, using a sterile deaerated culture medium inoculated with 10 % SRB concentrated at 108 cel/ml. The results indicate bacterial growth in the order of 109-1010 cel/ml after 18 h both in the polarized and non-polarized tests, indicating that SRB developed regardless of the surface polarized as a source of H0, generating H2S as a product of the anaerobic respiration. It was also determined that, without cathodic polarization, the conditions are not enough to reduce the H+ generated by the H2S dissociation (Pd is not susceptible to corrosion at this condition. On the other hand, cathodic polarization increased the permeation current, which was associated with the maximum enzymatic activity phase of the bacteria.En este trabajo se estudió la permeación del hidrógeno proveniente de una cepa pura de bacterias sulfato reductoras-BSR (Desulfovibrio desulfuricans ssp. desulfuricans, utilizando para ello el tipo de celda de permeación de hidrógeno y una lámina de paladio (Pd. Esto se hizo con la finalidad de evaluar la despolarización catódica como mecanismo de acción de las BSR en la corrosión inducida microbiológicamente. Los ensayos de permeación se realizaron sin y con polarización catódica, utilizando un medio de cultivo estéril desaireado e inoculado con 10 % de BSR a una concentración de 108 cel/ml. Los resultados obtenidos indicaron crecimiento en 109-1010 cel/ml a las 18 h tanto en los ensayos sin polarización como en aquellos con polarización, lo cual refleja que la BSR se desarrolla independientemente de una superficie polarizada como fuente de H0, generando H2S como

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

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    Jasmin Hurtado; Arturo Berastain

    2012-01-01

    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 a...

  1. Estudio bioquímico y molecular de la producción de precursores de carbamato de etilo por bacteria lácticas asociadas al proceso de vinificación

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    Araque Granados, Maria Isabel

    2010-01-01

    Las bacterias lácticas (BL) mas frecuentes aisladas de vino fueron estudiadas en su capacidad de degradación de la arginina y su implicación en la generación de precursores de carbamato de etilo (CE) como citrulina y carbamil fosfato. Todos los lactobacilos heterofermentativos así como Oenococcus oeni, Pediococcus pentosaceus y algunas cepas de Leuconostoc mesenteroides y Lactobacillus plantarum fueron positivas en cuanto a su capacidad de degradación. Así mismo también se estudio la presenci...

  2. 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

  3. Hemicorea asociada a toxoplasmosis cerebral y SIDA

    Directory of Open Access Journals (Sweden)

    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.

  4. Neumonía asociada al cuidado de la salud

    OpenAIRE

    Adrián Ceccato; Alejandra González; Marcela Heres; Graciela Peluffo; Alfredo Monteverde

    2014-01-01

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  6. 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

  7. Oclusión arterial aguda asociada a hidatidosis diseminada

    Directory of Open Access Journals (Sweden)

    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

  8. 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.

  9. Neumonía asociada al cuidado de la salud

    Directory of Open Access Journals (Sweden)

    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.

  10. 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...

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

    OpenAIRE

    Alejandra Acosta-Gualandri; Kathia Valverde-Muñoz

    2011-01-01

    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. 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

  13. 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...

  14. 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

  15. 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...

  16. Big bacteria

    DEFF Research Database (Denmark)

    Schulz, HN; Jørgensen, BB

    2001-01-01

    A small number of prokaryotic species have a unique physiology or ecology related to their development of unusually large size. The biomass of bacteria varies over more than 10 orders of magnitude, from the 0.2 mum wide nanobacteria to the largest cells of the colorless sulfur bacteria......, Thiomargarita namibiensis, with a diameter of 750 mum. All bacteria, including those that swim around in the environment, obtain their food molecules by molecular diffusion. Only the fastest and largest swimmers known, Thiovulum majus, are able to significantly increase their food supply by motility and by...... actively creating an advective flow through the entire population. Diffusion limitation generally restricts the maximal size of prokaryotic cells and provides a selective advantage for mum-sized cells at the normally low substrate concentrations in the environment. The largest heterotrophic bacteria, the...

  17. 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 ...

  18. Representaciones sociales asociadas al consumo hedónico de alimentos en restaurantes

    Directory of Open Access Journals (Sweden)

    Claudia Mercedes Padrón Mercado

    2011-01-01

    Full Text Available Esta investigación tuvo como objetivo establecer las representaciones sociales asociadas al consumo hedónico de alimentos en restaurantes para personas de los estratos 2 al 6 en la ciudad de Bogotá ¿ Colombia. Se realizó un estudio descriptivo multidimensional basado en los resultados de una encuesta estructurada con preguntas abiertas y cerradas. Para el análisis de los datos se emplearon análisis lexicométricos y análisis Multivariados. Los resultados dan a conocer el núcleo central y sistema periférico de las representaciones sociales asociadas al consumo hedónico de alimentos, donde se observaron aspectos personales, sociales y culturales que permitieron realizar una segmentación psicográfica de acuerdo a las características de diferentes tipos de comensales encontrados.

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. 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...

  4. 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 ...

  5. 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...

  6. 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...

  7. 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 ...

  8. Construyendo resiliencia ante shocks adversos: Factores y estrategias asociadas a la vulnerabilidad y la resiliencia

    OpenAIRE

    Andersen, Lykke E.; Cardona, Marcelo

    2014-01-01

    Este documento presenta una metodología para medir la diversificación de los medios de vida de los hogares. Esta medida, junto a los niveles de ingresos de los hogares, nos permite clasificarlos según la vulnerabilidad que estos pudieran tener. Aplicamos análisis de regresión para detectar los factores y estrategias asociadas a resiliencia y a vulnerabilidad. Los resultados muestran que la estrategia más importante para lograr resiliencia es que los hogares cuenten con una esposa que aporte a...

  9. Nefritis tubulo intersticial asociada a parvovirus b19 Tubulointerstitial nephritis associated with parvovirus b19 infection

    OpenAIRE

    José A. Ramírez; Paula A. Coccía; Hilario A. Ferrero; Beatriz Livellara; Silvia Christiansen; Guillermo Gallo

    2005-01-01

    Paciente de 9 años, previamente sana, que ingresa en anasarca con síndrome nefrótico clínico y humoral, asociado a hipertensión arterial y microhematuria, con función renal normal y se comporta como corticorresistente. Se realiza 1° biopsia renal que informa glomerulonefritis proliferativa mesangial difusa con esclerosis focal y segmentaria. En tratamiento con ciclofosfamida y corticoides, presenta síndrome febril prolongado con anemia secundaria a crisis aplásica de la serie roja, asociada c...

  10. Neumonía intersticial linfoidea asociada a inmunodeficiencia común variable

    OpenAIRE

    2011-01-01

    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 t...

  11. 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.

  12. 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

  13. 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

  14. 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

  15. Modelación molecular de rodopsinas humanas mutantes asociadas a retinosis pigmentaria

    OpenAIRE

    Hernández Rodríguez, Erix William

    2014-01-01

    En este trabajo, se realiza una nueva aplicación combinada de modelación por homología, dinámica molecular clásica, teoría de funcionales de la densidad, deformaciones de la densidad electrónica y el método híbrido mecánica cuántica/mecánica molecular para evaluar propiedades geométricas, electrónicas y fotoquímicas en rodopsinas mutantes portadoras de las sustituciones M207R y S186W asociadas a Retinosis Pigmentaria (RP). Nuestros resultados para las rodopsinas bovina y humana normales, usad...

  16. 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.

  17. Back To Bacteria.

    Science.gov (United States)

    Flannery, Maura C.

    1997-01-01

    Explores new research about bacteria. Discusses bacterial genomes, archaea, unusual environments, evolution, pathogens, bacterial movement, biofilms, bacteria in the body, and a bacterial obsession. Contains 29 references. (JRH)

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. 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.

  3. Respuesta neuroinmunológica en la encefalitis asociada al virus del dengue

    Directory of Open Access Journals (Sweden)

    Bárbara Padilla-Docal

    2013-12-01

    Full Text Available El virus del dengue es un virus ARN miembro de la familia Flaviviridae, la cual incluye, además, el de la fiebre amarilla, el del Nilo del Oeste y la encefalitis japonesa. Se realizó un estudio retrospectivo con tres pacientes diagnosticados de encefalitis asociada al dengue, en cuyas muestras de suero y líquido cefalorraquídeo se cuantificaron los niveles de las clases mayores de inmunoglobulinas por inmunodifusión radial y la manosa de unión a lectina, proteína de la vía de las lectinas del sistema del complemento por fluorometría. En el reibergrama se muestra la presencia de síntesis intratecal de las tres clases de inmunoglobulinas y ausencia de síntesis intratecal de lectina de unión a manosa. Existieron diferencias en cuanto al por ciento de síntesis intratecal de inmunoglobulinas, las cuales estuvieron relacionadas con el momento de la infección por el virus y la aparición de las manifestaciones neurológicas compatibles con una encefalitis. Este es el primer reporte de afectaciones neurológicas en pacientes cubanos con dengue. La respuesta inmune intratecal puede ser utilizada para el mejor conocimiento de la enfermedad y contribuir al desarrollo de posibles candidatos vacunales.

  4. 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.

  5. IMIQUIMOD EN CREMA AL 5% EN EL TRATAMIENTO DE VERRUGAS ANOGENITALES ASOCIADAS A VPH: EXPERIENCIA PRELIMINAR

    Directory of Open Access Journals (Sweden)

    Omar Nazzal N

    2008-01-01

    Full Text Available Antecedentes: La infección persistente por VPH de alto riesgo se asocia con cáncer cervicouterino, encontrándose positividad en el 99,7% de los casos. Las verrugas anogenitales son una forma de presentación de la infección persistente. Objetivo: Investigar la eficacia y seguridad de imiquimod en crema al 5%, en el tratamiento de las verrugas anogenitales en mujeres. Método: Estudio prospectivo no randomizado, en mujeres portadoras de verrugas anogenitales asociadas a VPH. El tratamiento consiste en la autoaplicación de imiquiomod en crema al 5% tres veces a la semana por hasta un período de 16 semanas. Se define como respuesta completa al tratamiento aquella en que desaparece completamente la lesión; por respuesta parcial la disminución de al menos un 50% del volumen inicial de la lesión. Resultados: Durante un período de 8 meses fueron ingresadas y tratadas 38 pacientes La duración del tratamiento varió entre 1 y 4 meses. El número promedio de aplicaciones fue de 28,7. El 66% (25 casos de las pacientes presentaron una respuesta completa, en tres casos no hubo respuesta, uno de ellos en una paciente inmunodeprimida, en 10 casos hubo respuestas parciales. En las pacientes con respuestas completas se necesitó un promedio de 28,7 aplicaciones hasta obtener el resultado. Conclusiones: Imiquimod es un fármaco con buena efectividad y seguridad en el tratamiento de las verrugas anogenitales asociadas a VPH, en tratamiento de tres veces por semana durante mínimo de 10 semanas.Background: The chronic infection by high-risk HPV serotypes is bly associated with cervical cáncer, detection of HPV on tissue sample has been reported 99.7% of cases. The anal-genital warts represent the clinical manifestation of the persistent infection by this virus. Objectives: To investígate the efficacy and safe-ty of Imiquimod cream 5% concentration, in the treatment of anal-genital warts in women. Methods: A non-randomized prospective study in women

  6. 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

  7. 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 ...

  8. 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.

  9. 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...

  10. Displasia de Mondini asociada a meningitis bacteriana recurrente, correlación clínico-imagenológica

    OpenAIRE

    Julianis Loraine Quintero Noa; María del Carmen Hernández Cordero; Ileana Álvarez Lam; Aiza Martínez Romero; Antonio Paz Cordovés; Daisy Hevia Bernal

    2014-01-01

    Se describe la displasia de Mondini asociada a pérdida auditiva y meningitis bacteriana recurrente. La malformación de Mondini representa el 30 % de las anomalías congénitas del oído interno, puede ser unilateral o bilateral, y su principal característica consiste en el desarrollo coclear incompleto, causante de grados variables de hipoacusia neurosensorial. Se considera que la ocurrencia de esta malformación se produce por disrupción del desarrollo embrionario durante la séptima semana de ge...

  11. 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...

  12. 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 ...

  13. 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...

  14. Plan de cuidados estandarizado del paciente con degeneración macular asociada a la edad (DMAE)

    OpenAIRE

    Álvarez Cano, Laura

    2013-01-01

    En la actualidad los planes de cuidados de enfermería estandarizados son una herramienta muy útil para organizar el trabajo de enfermería y aplicar unos cuidados eficientes y de calidad a los pacientes. Elpresente trabajose centra en desarrollar un plan de cuidados estandarizado para los pacientes con Degeneración Macular Asociada a la Edad (DMAE), que es la principal causa de ceguera legal en los países desarrollados. En el plan de cuidados de enfermería, tomando como referente la perspectiv...

  15. Observaciones histológicas de estructuras celulares asociadas a spongospora subterranea f sp. subterranea en papa.

    OpenAIRE

    Hoyos Carvajal, Liliana; Villegas Ochoa, Marcela; González Jaimes, Elena Paola

    2011-01-01

    Spongospora subterranea (Wallroth) Lagerheim f. sp. subterranea Tomlinson, agente causal de la sarna polvosa de la papa, es un parásito obligado el cual por sus características biológicas y reproductivas, posee una gran capacidad de sobrevivencia e infección no solo en su principal hospedero, sino también en diversas especies silvestres. El objetivo de este estudio fue realizar observaciones de estructuras celulares asociadas a S. subterranea f. sp. subterranea en plantas de papa en diferente...

  16. 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.

  17. 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...

  18. Encefalopatía Asociada A Trastornos Renales En Perros y Gatos: Revisión Bibliográfica

    OpenAIRE

    Pellegrino, Fernando Carlos

    2009-01-01

    La encefalopatía asociada a trastornos renales es una condición mal defi nida, reportada infrecuentemente en perros y gatos con insufi ciencia renal. Esta categoría de encefalopatía metabólica incluye la encefalopatía urémica, el síndrome de desequilibrio de diálisis, la demencia dialítica y la encefalitis postrasplante. Los trastornos de la conciencia y la actividad convulsiva son anormalidades típicas de este trastorno. Otros signos clínicos pueden incluir tremores musculare...

  19. 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...

  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. 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.

  2. Nefritis tubulo intersticial asociada a parvovirus b19 Tubulointerstitial nephritis associated with parvovirus b19 infection

    Directory of Open Access Journals (Sweden)

    José A. Ramírez

    2005-08-01

    Full Text Available Paciente de 9 años, previamente sana, que ingresa en anasarca con síndrome nefrótico clínico y humoral, asociado a hipertensión arterial y microhematuria, con función renal normal y se comporta como corticorresistente. Se realiza 1° biopsia renal que informa glomerulonefritis proliferativa mesangial difusa con esclerosis focal y segmentaria. En tratamiento con ciclofosfamida y corticoides, presenta síndrome febril prolongado con anemia secundaria a crisis aplásica de la serie roja, asociada con una infección aguda por parvovirus B19, e insuficiencia renal aguda secundaria a nefritis tubulointersticial severa. La PCR para parvovirus B19 DNA fue positiva en tejido renal y médula ósea. La paciente evoluciona a insuficiencia renal crónica terminal. No se puede descartar que desde su inicio, el síndrome nefrótico estuviera asociado al daño glomerular por la infección viral, que comenzó como síndrome nefrótico con componentes nefríticos y que evoluciona inesperadamente a una nefritis tubulointersticial. Este sería el primer caso en el que se documenta como causa de insuficiencia renal crónica terminal, un daño tubulointersticial secundario a parvovirus B19.A previously healthy 9 year old girl developed nephrotic syndrome with hypertension, microhematuria and normal renal function. The patient evolved as steroid resistant nephrotic syndrome whose initial renal biopsy was consistent with diffuse proliferative mesangial glomerulonephritis with focal segmental glomerulosclerosis. At the time of cyclophosphamide and prednisone treatment, she developed a prolonged febrile syndrome. She also had severe anemia following an aplastic crisis induced by human parvovirus B19 infection and acute renal failure secondary to a severe tubulointersticial disease. Bone marrow and renal tissue, tested by polimerase chain reaction were positive for parvovirus, while the patient’s blood was negative. The renal involvement did not improve requiring

  3. 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....

  4. 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...

  5. Diferencias regionales en la mortalidad urbana asociada a la nutrición en la España contemporánea (1900-1974)

    OpenAIRE

    Castelló Botía, Isabel; Pina Romero, José Aurelio

    2004-01-01

    A lo largo del siglo XX, la población española fue consolidando su proceso de transición demográfica y nutricional. A medida que fue avanzando el siglo, las causas de mortalidad asociadas a nutrición de la población urbana fueron variando desde muertes por desnutrición y enfermedades infecciosas transmitidas por agua y alimentos (diarrea, clorosis, avitaminosis, fiebre tifoidea) en una primera etapa del siglo y en la etapa de la posguerra, hasta muertes asociadas a malnutrición en exceso (dia...

  6. 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...

  7. 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%...

  8. 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.

  9. 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...

  10. Amenazas naturales asociadas al ascenso del nivel del mar en Caribe Colombiano

    Directory of Open Access Journals (Sweden)

    Robertson Kim Gregory

    2003-01-01

    Full Text Available Se presentan los resultados de recientes investigaciones sobre el impacto del ascenso del nivel del mar en la Costa Caribe colombiana, bases para el primer informe de Colombia a la Convención Internacional de Cambio Climático, adelantado en convenio con elIDE..-.1f. Con base en el estudio de las geoformas litorales, los procesos dinámicos asociadosy su evolución reciente, se evaluó la amenaza por inundación y erosión asociada al actual ascenso del nivel del mar, proyectado por IP(C (panel Intergubemamcntal de Expertos de Cambio Climático en un metro pata el año 2100. A partir de la interpretación de imágenes de satélite y fotografias aéreas, apoyada en información secundaria y verificación de campo, se identificaron 15 unidades geomorfológicas básicas de origen estructural, fluvial y marino. Con base las características geomorfológicas y criterios de resiliencia frente a la acción del oleaje y la inundación litoral, se generó un modelo morfodinámico que pronostica el impacto del ascenso del nivel marino para el litoral Caribe colombiano. De acuerdo con este análisis, se estima que las unidades geomorfológicas recientes desarrolladas durante los últimos 2.500 años podrían ser reactivadas por el actual ascenso del nivel del mar, afectando numerosos centros urbanos tales como Cartagena, Santa Marta, Puerto Colombia y Turbo y actividades económicas de-importancia como el comercio portuario y el turismo. Para los 1.819 Km. de línea de costa del Caribe Colombiano, se estima que el 33.7% presenta alta susceptibilidad a la erosión marina, representado por geoformas que presentan grari fragilidad ante los procesos erosivos. En la linea de costa restante, 31,2% presenta susceptibilidad mec!ia y 35.1% susceptibilidad baja y muy baja, en una linea de costa caracterizada por geoformas con fragilidad y mecanismos de resiliencia variables. Por inundación, se pronostica que 1192 Km2 de costa baja serán anegados, 2331 Km2 sufrir

  11. Reduced environments for production of culture susceptible aquatic organisms for human consumption

    Directory of Open Access Journals (Sweden)

    Patricia Edurne Sánchez Meza

    2009-01-01

    Full Text Available Los sedimentos anóxicos propician proliferación de bacterias sulfato-reductoras, característica principal de los ambientes reducidos, que se aprovechan para el cultivo de crustáceos. En México se ha notifi cado presencia de sedimentos anóxicos en los canales de Xochimilco, ambiente reducido, que podrían aprovecharse para el cultivo de organismos, como el acocil (Cambarellus montezumae. El objetivo del presente estudio fue probar que los ambientes reducidos pueden ser útiles para la producción de organismos acuáticos susceptibles de cultivo, y además, para consumo humano. Se caracterizaron los canales Apatlaco y Cuemanco como ambientes reducidos, se evaluaron parámetros fi sicoquímicos del agua y sedimento; se determinaron metales pesados en sedimento y organismo; se comprobó la presencia y calidad sanitaria del acocil, a través de los análisis cualitativo y cuantitativo de su carga bacteriana; se determinó la calidad nutrimental de los acociles por medio de análisis químico proximal. Se probó que los canales de Xochimilco cumplen con las características de ambiente reducido, en el que se comprobó presencia del acocil (C. montezumae. Se demostró que los niveles de metales pesados y carga bacteriana registrados no superan los límites máximos permisibles para crustáceos comestibles, fuente importante de proteínas para el consumo humano. Con base en lo anterior se afi rma que los ambientes reducidos pueden ser aprovechados para el cultivo de especies acuáticas comestibles.

  12. Aerobic Anoxygenic Phototrophic Bacteria

    OpenAIRE

    Yurkov, Vladimir V.; Beatty, J. Thomas

    1998-01-01

    The aerobic anoxygenic phototrophic bacteria are a relatively recently discovered bacterial group. Although taxonomically and phylogenetically heterogeneous, these bacteria share the following distinguishing features: the presence of bacteriochlorophyll a incorporated into reaction center and light-harvesting complexes, low levels of the photosynthetic unit in cells, an abundance of carotenoids, a strong inhibition by light of bacteriochlorophyll synthesis, and the inability to grow photosynt...

  13. 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.

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

    OpenAIRE

    Irina Salgado-Bernal; Armando Martínez-Sardiñas; María Elena Carballo-Valdés; Mario Cruz- Arias; María del Carmen Durán-Domínguez

    2012-01-01

    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 l...

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

    OpenAIRE

    2013-01-01

    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 fre...

  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. Comorbilidad asociada en un grupo de consumidores de heroína de Medellín

    Directory of Open Access Journals (Sweden)

    Guillermo Alonso Castaño Pérez

    2010-02-01

    Full Text Available Introducción: Este artículo revisa la comorbilidad física y mental asociada con el consumo de drogas en un grupo de 42 consumidores de heroína en la ciudad de Medellín (Colombia, quienes fueron contactados en centros de tratamiento y por medio de la técnica bola de nieve. Método: Entrevistas semiestructuradas para recolectar información sobre su perfil sociodemográfico, vías de administración, prácticas de consumo, rituales, intercambio de utensilios, relaciones sexuales y protección, ideas e intentos suicidas, antecedentes familiares y personales de enfermedad y presencia de morbilidad física y mental. Resultados: Dichos consumidores son predominantemente hombres, solteros, con edades entre los 18 y los 23 años, sin hijos y muchos con estudios universitarios que aún no terminan. Mayoritariamente se ubican en un estrato socioeconómico medio y tienen antecedentes familiares de consumo de sustancias psicoactivas. Todos presentan historia de policonsumo de sustancias psicoactivas. Los consumidores comparten jeringas y otros utensilios, y tienen frecuentemente prácticas de sexo no seguro. Respecto a la comorbilidad asociada, se destacan los trastornos alimentarios, el insomnio, las alteraciones cardiovasculares y autónomo-vegetativas, entre los que se aparecen la sudoración y las variaciones en la temperatura corporal. También se encontró la presencia de sobredosis, las ideas recurrentes de suicidio y, en menor medida, las enfermedades infectocontagiosas

  20. 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.

  1. 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

  2. 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.

  3. Oil eating bacteria

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    The article discusses the unusual technology of using oil-eating bacteria to increase oil recovery. The background for the discovery that bacteria injection into the reservoirs may increase the oil recovery is the study of microbial action in breaking down oil pollution. About 20 per cent of the organisms living naturally in the sea can eat oil. But they need water to grow. In the absence of water, the bacteria produce enzymes to make the oil water soluble and allow them to extract nutrients from them. Oil does not vanish upon being eaten, but enzymes from the digestive process act as effective detergents to wash away the oil, which is then easier to recover.

  4. 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. ...

  5. Immunity to intracellular bacteria

    OpenAIRE

    Stefan H. E. Kaufmann; Follows, George A.; Martin E. Munik

    1992-01-01

    Immunity to intracellular bacteria including Mycobacterium tuberculosis. Mycobacterium leprae, and Listeria monocytogenes depends on specific T cells. Evidence to be described suggests that CD4 (alpha/beta)T cells which interact with each other and with macrophages contribute to acquired resistence against as well as pathogenesis of intracellular bacterial infections.

  6. Immunity to intracellular bacteria

    Directory of Open Access Journals (Sweden)

    Stefan H. E. Kaufmann

    1992-01-01

    Full Text Available Immunity to intracellular bacteria including Mycobacterium tuberculosis. Mycobacterium leprae, and Listeria monocytogenes depends on specific T cells. Evidence to be described suggests that CD4 (alpha/betaT cells which interact with each other and with macrophages contribute to acquired resistence against as well as pathogenesis of intracellular bacterial infections.

  7. 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

  8. 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.

  9. Cable Bacteria in Freshwater Sediments

    OpenAIRE

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus B.; Dittmer, Anders Lindequist; Bjerg, Jesper Tataru; Trojan, Daniela; Schreiber, Lars; Damgaard, Lars Riis; Schramm, Andreas; Nielsen, Lars Peter

    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 fre...

  10. 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.

  11. 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.

  12. 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

  13. Bacteria, Phages and Septicemia

    OpenAIRE

    Gaidelytė, Aušra; Vaara, Martti; Bamford, Dennis H.

    2007-01-01

    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 ph...

  14. Bacteria, food, and cancer

    OpenAIRE

    Rooks, Michelle G.; Garrett, Wendy S.

    2011-01-01

    Gut microbes are essential components of the human organism—helping us metabolize food into energy, produce micronutrients, and shape our immune systems. Having a particular pattern of gut microbes is also increasingly being linked to medical conditions including obesity, inflammatory bowel disease, and diabetes. Recent studies now indicate that our resident intestinal bacteria may also play a critical role in determining one's risk of developing cancer, ranging from protection against cancer...

  15. Lethal Mutagenesis of Bacteria

    OpenAIRE

    Bull, James J; Wilke, Claus O.

    2008-01-01

    Lethal mutagenesis, the killing of a microbial pathogen with a chemical mutagen, is a potential broad-spectrum antiviral treatment. It operates by raising the genomic mutation rate to the point that the deleterious load causes the population to decline. Its use has been limited to RNA viruses because of their high intrinsic mutation rates. Microbes with DNA genomes, which include many viruses and bacteria, have not been considered for this type of treatment because their low intrinsic mutatio...

  16. Bacteria are not Lamarckian

    OpenAIRE

    Danchin, Antoine

    2007-01-01

    Instructive influence of environment on heredity has been a debated topic for centuries. Darwin's identification of natural selection coupled to chance variation as the driving force for evolution, against a formal interpretation proposed by Lamarck, convinced most scientists that environment does not specifically instruct evolution in an oriented direction. This is true for multicellular organisms. In contrast, bacteria were long thought of as prone to receive oriented influences from their ...

  17. Denitrification by extremely halophilic bacteria

    Science.gov (United States)

    Hochstein, L. I.; Tomlinson, G. A.

    1985-01-01

    Extremely halophilic bacteria were isolated from widely separated sites by anaerobic enrichment in the presence of nitrate. The anaerobic growth of several of these isolates was accompanied by the production of nitrite, nitrous oxide, and dinitrogen. These results are a direct confirmation of the existence of extremely halophilic denitrifying bacteria, and suggest that such bacteria may be common inhabitants of hypersaline environments.

  18. 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

  19. Prevalencia de patología musculoesquelética asociada al síndrome de falla cardiaca

    Directory of Open Access Journals (Sweden)

    Juan Manuel Sénior

    2014-07-01

    Full Text Available Introducción: en pacientes con falla cardiaca se han descrito múltiples patologías asociadas, en especial las de origen musculoesquelético que pueden limitar la capacidad funcional, independiente de la función ventricular y deteriorar la calidad de vida de los pacientes, por lo que su detección permite realizar cambios en la prescripción del ejercicio y en el acondicionamiento aeróbico, aplicar medidas fisioterapéuticas y ergonómicas en los programas de rehabilitación cardiaca acorde con el diagnóstico específico. Material y métodos: estudio descriptivo, de corte transversal y retrospectivo de los pacientes que ingresaron a la Clínica de Falla Cardiaca de la Universidad de Antioquia y el Hospital Universitario San Vicente de Paúl Fundación en un periodo de un año, con el objetivo de establecer la presencia de patología musculoesquelética. Resultados: se ingresaron 151 pacientes durante el periodo de estudio. El 55.6% fueron hombres y la mediana de edad fue de 68 años. La primera causa de falla cardiaca fue la enfermedad coronaria, seguida de la hipertensión arterial. El 33.1% estuvieron en clase funcional de la Asociación de Corazón de Nueva York (NYHA II y el 32.5% en NYHA III. El 66.9% de los pacientes que asisten a la Clínica de Falla Cardiaca no tenían actividad laboral. Se demostró patología musculoesquelética en 31.8%, siendo la más común la osteoartritis, bien sea de cadera o rodillas, con una frecuencia de 6.6%, seguida de la tendinitis del manguito rotador (4,6%. Otras alteraciones encontradas fueron dolor lumbar, dolor miofascial, neuropatía periférica, disfunción patelofemoral y síndrome de túnel carpiano. El 35.8% de los pacientes se lograron vincular al programa de rehabilitación cardiaca y establecer un programa dirigido, de acuerdo con las comorbilidades encontradas. Conclusiones: la patología osteomuscular en pacientes con falla cardiaca es frecuente, posiblemente por cambios metabólicos e

  20. 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

  1. 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.

  2. 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

  3. Bacteria counting method based on polyaniline/bacteria thin film.

    Science.gov (United States)

    Zhihua, Li; Xuetao, Hu; Jiyong, Shi; Xiaobo, Zou; Xiaowei, Huang; Xucheng, Zhou; Tahir, Haroon Elrasheid; Holmes, Mel; Povey, Malcolm

    2016-07-15

    A simple and rapid bacteria counting method based on polyaniline (PANI)/bacteria thin film was proposed. Since the negative effects of immobilized bacteria on the deposition of PANI on glass carbon electrode (GCE), PANI/bacteria thin films containing decreased amount of PANI would be obtained when increasing the bacteria concentration. The prepared PANI/bacteria film was characterized with cyclic voltammetry (CV) technique to provide quantitative index for the determination of the bacteria count, and electrochemical impedance spectroscopy (EIS) was also performed to further investigate the difference in the PANI/bacteria films. Good linear relationship of the peak currents of the CVs and the log total count of bacteria (Bacillus subtilis) could be established using the equation Y=-30.413X+272.560 (R(2)=0.982) over the range of 5.3×10(4) to 5.3×10(8)CFUmL(-1), which also showed acceptable stability, reproducibility and switchable ability. The proposed method was feasible for simple and rapid counting of bacteria. PMID:26921555

  4. Rehabilitación Visual en Degeneración Macular Asociada a la Edad: Revisión Bibliográfica

    OpenAIRE

    Lago Álvarez, Manuel

    2013-01-01

    La degeneración macular asociada a la edad (DMAE) es una de las patologías visuales más incapacitantes que existen en la actualidad. Afecta principalmente a la visión central, por lo que actividades que requieran fijación tales como la lectura, ver la televisión o reconocer caras van a estar severamente perjudicadas. Asociado a esto aparecen síntomas característicos de la depresión o sentimientos negativos como la baja autoestima. En global, los afectados de DMAE sufren un gran deterioro en s...

  5. 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...

  6. 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 ...

  7. 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. ...

  8. 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...

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

    OpenAIRE

    Guarrochena de Arjol, Marina; Paul, Liliana Martina

    2013-01-01

    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 comp...

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

    OpenAIRE

    Jairo Edielson Rodrigues Barbosa de Sousa; Grazielle Roberta Freitas Da Silva; Maria Helena Barros Araújo Luz; Marcio Leonardo Lima Pereira

    2015-01-01

    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 T...

  11. 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...

  12. Estrategias para la participación de los trabajadores en mejoras tecnológicas asociadas a la industria metalúrgica venezolana

    OpenAIRE

    Cova, Milagros Isabel; Anzola, Minerva; Rodríguez Monroy, Carlos

    2015-01-01

    Se planteó la generación y sistematización de estrategias para la participación de los trabajadores en mejoras tecnológicas asociadas a la industria metalúrgica venezolana. Se desarrolló una estrategia de acompañamiento desde la investigación acción participativa (IAP), la ‘investigación próxima’, mediante talleres de formación-investigación y la sistematización de experiencias considerando la perspectiva y necesidades de los actores. Bajo este enfoque, se ejecutaron 10 talleres (de tres ...

  13. 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 ...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. Incidencia y consecuencias de la traqueobronquitis asociada a ventilación mecánica en unidades de cuidados intensivos

    OpenAIRE

    Anselmo Abdo Cuza; Roberto Castellanos-Gutiérrez; Julio César González-Aguilera; Reinaldo Reyes-Tornés; Yoleinis Vázquez-Belizón; Manuel Ernesto Somoza-García; Javier Casas-Rodríguez; Anabel Barani-Larrazabal; Adriel Viera-Paz; Alejandro Vázquez-Soto; Abel Corcho-Martínez; Carlos Roberto Valdés-Riñak; Bárbara Reigoso-Cruz; Lissette del Rosario López-González; Daysi Eduarda Álvarez-Montalvo

    2013-01-01

    Introducción: las infecciones respiratorias bajas ocupan el primer lugar entre las infecciones relacionadas con el cuidado sanitario en unidades de cuidados intensivos. Objetivos: describir la incidencia y las consecuencias, sobre estadía y mortalidad, de la traqueobronquitis asociada a ventilación mecánica (TAVM) en UCI. Métodos: estudio multricéntrico, descriptivo, prospectivo y transversal, en 6 UCI de adultos. Se estudiaron 454 pacientes. Las variables de estudio fueron recogidas en 2 bas...

  19. 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...

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

    OpenAIRE

    Gonzalo Peralta; Renzo Villagomez; Martín Bosio; Silvia Quadrelli; Julio Chertcoff; Félix Vigovich

    2011-01-01

    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 t...

  1. 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...

  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. Lactic Acid Bacteria

    Directory of Open Access Journals (Sweden)

    ToddKlaenhammer

    2013-04-01

    Full Text Available Lactic acid bacteria (LAB are a diverse group of Gram-positive bacteria found in a vast array of environments including dairy products and the human gastrointestinal tract. In both niches, surface proteins play a crucial role in mediating interactions with the surrounding environment. The sortase enzyme is responsible for covalently coupling a subset of surface dependent proteins (SDPs to the cell wall of Gram-positive organisms through recognition of a conserved C-terminal LPXTG motif. Genomic sequencing of LAB and annotation has allowed for the identification of sortase and SDPs. Historically, sortase and SDPs were predominately investigated for their role in mediating pathogenesis. Identification of these proteins in LAB has shed light on their important roles in mediating nutrient acquisition through proteinase P as well as positive probiotic attributes including adhesion, mucus barrier function, and immune signaling. Furthermore, sortase expression signals in LAB have been exploited as a means to develop oral vaccines targeted to the gastrointestinal tract. In this review, we examine the collection of studies which evaluate sortase and SDPs in select species of dairy associated and health promoting LAB.

  4. 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...

  5. Modificacion del Valor Nutrimental de Acidos Grasos en Semilla de la Halofita Salicornia bigelovii Torr. con la Interaccion de Bacterias Promotoras del Crecimiento de Plantas (Azospirillum halopraeferens y Klebsiella pneumoniae)

    OpenAIRE

    Edgar Omar Rueda Puente; Enrique Troyo Dieguez; Thelma Castellanos Cervantes; Bernardo Murillo-Amador; Bertha Olivia Arredondo Vega; Jose Luis Díaz de Leon Alvarez; Mario Antonio Tarazon Herrera

    2005-01-01

    Una especie vegetal a gran escala se presenta como una alternativa para la producción de ácidos grasos esenciales en nutrición humana por lo que su composición de ácidos grasos cobra especial importancia. Salicornia bigelovii una halófita que se desarrolla en ambientes áridos y costeros como las del estado de Sonora y de la península de Baja California Sur, México, presenta ser una especie alternativa en la producción de aceites comestibles. La fijación de N2 por bacterias asociadas con raíce...

  6. 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.

  7. 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.

  8. 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.

  9. 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 and...... 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...

  10. 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 is...... cytokines when stimulated 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...

  11. Interactions between Diatoms and Bacteria

    OpenAIRE

    Amin, Shady A.; Parker, Micaela S.; Armbrust, E. Virginia

    2012-01-01

    Summary: Diatoms and bacteria have cooccurred in common habitats for hundreds of millions of years, thus fostering specific associations and interactions with global biogeochemical consequences. Diatoms are responsible for one-fifth of the photosynthesis on Earth, while bacteria remineralize a large portion of this fixed carbon in the oceans. Through their coexistence, diatoms and bacteria cycle nutrients between oxidized and reduced states, impacting bioavailability and ultimately feeding hi...

  12. 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.)

  13. 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.

  14. 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.

  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. 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...

  18. 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...

  19. 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

  20. 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.

  1. 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...

  2. 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.

  3. 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

  4. 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

  5. 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...

  6. 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.

  7. 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.

  8. Distribución vertical de arañas asociadas a quercus humboldtii y clusia spp. en el santuario de fauna y flora iguaque, colombia

    OpenAIRE

    VANEGAS, SILVIA; FAGUA, GIOVANNY; FLOREZ, EDUARDO

    2012-01-01

    Se estudió la distribución vertical de arañas asociadas a Quercus humboldtii y Clusia spp. en el Santuario de Fauna y Flora Iguaque, para esto se seleccionaron 10 árboles de cada género estratificándolos verticalmente cada 3m desde la base hasta el dosel. Se realizaron colectas en cada estrato por 20 min durante el día y en la noche. También se tomaron muestras en la parcela aledaña (4 m2). Se colectaron 1.261 individuos pertenecientes a 104 morfoespecies y 20 familias; las más frecuentes fue...

  9. 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.

    increased. It is only recently that sewage from major cities like Panaji, Goa, India is treated before disposing into the estuary. It is therefore of interest to determine what the levels of pollution indicator bacteria due to sewage disposal...

  10. 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.

  11. 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.

  12. 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...... TKs from Gram-positive bacteria are more closely related to the eukaryotic TK1 enzymes than are TKs from Gram-negative bacteria....

  13. LACTIC ACID BACTERIA: PROBIOTIC APPLICATIONS

    OpenAIRE

    NEENA GARG

    2015-01-01

    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. LA...

  14. 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 ...

  15. Thymidine kinase diversity in bacteria

    DEFF Research Database (Denmark)

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

    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...... TKs from Gram-positive bacteria are more closely related to the eukaryotic TK1 enzymes than are TKs from Gram-negative bacteria....

  16. 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.

  17. Cable Bacteria in Freshwater Sediments.

    Science.gov (United States)

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus B; Dittmer, Anders Lindequist; Bjerg, Jesper Tataru; Trojan, Daniela; Schreiber, Lars; Damgaard, Lars Riis; Schramm, Andreas; Nielsen, Lars Peter

    2015-09-01

    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 and electric fields indicated electron transfer between vertically separated anodic and cathodic half-reactions. Fluorescence in situ hybridization revealed the presence of Desulfobulbaceae filaments. In addition, in situ measurements of oxygen, pH, and electric potential distributions in the waterlogged banks of Giber Å demonstrated the presence of distant electric redox coupling in naturally occurring freshwater sediment. At the same site, filamentous Desulfobulbaceae with cable bacterium morphology were found to be present. Their 16S rRNA gene sequence placed them as a distinct sister group to the known 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 origin of the cable phenotype within Desulfobulbaceae with subsequent diversification into a freshwater and a marine lineage. PMID:26116678

  18. 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.

  19. 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.

  20. 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.

  1. IDENTIFICATION OF BACTERIA IN LATEX PAINTS

    Directory of Open Access Journals (Sweden)

    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.

  2. Electron transport chains of lactic acid bacteria

    OpenAIRE

    Brooijmans, R.J.W.

    2008-01-01

    Lactic acid bacteria are generally considered facultative anaerobic obligate fermentative bacteria. They are unable to synthesize heme. Some lactic acid bacteria are unable to form menaquinone as well. Both these components are cofactors of respiratory (electron transport) chains of prokaryotic bacteria. Lactococcus lactis, and several other lactic acid bacteria, however respond to the addition of heme in aerobic growth conditions. This response includes increased biomass and robustness. In t...

  3. 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....

  4. 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

  5. Parotitis due to anaerobic bacteria.

    Science.gov (United States)

    Matlow, A; Korentager, R; Keystone, E; Bohnen, J

    1988-01-01

    Although Staphylococcus aureus remains the pathogen most commonly implicated in acute suppurative parotitis, the pathogenic role of gram-negative facultative anaerobic bacteria and strict anaerobic organisms in this disease is becoming increasingly recognized. This report describes a case of parotitis due to Bacteroides disiens in an elderly woman with Sjögren's syndrome. Literature reports on seven additional cases of suppurative parotitis due to anaerobic bacteria are reviewed. Initial therapy of acute suppurative parotitis should include coverage for S. aureus and, in a very ill patient, coverage of gram-negative facultative organisms with antibiotics such as cloxacillin and an aminoglycoside. A failure to respond clinically to such a regimen or isolation of anaerobic bacteria should lead to the consideration of the addition of clindamycin or penicillin. PMID:3287567

  6. 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

  7. 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

  8. 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

  9. 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...

  10. Role of Bacteria in Oncogenesis

    OpenAIRE

    Chang, Alicia H; Parsonnet, Julie

    2010-01-01

    Summary: Although scientific knowledge in viral oncology has exploded in the 20th century, the role of bacteria as mediators of oncogenesis has been less well elucidated. Understanding bacterial carcinogenesis has become increasingly important as a possible means of cancer prevention. This review summarizes clinical, epidemiological, and experimental evidence as well as possible mechanisms of bacterial induction of or protection from malignancy.

  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. 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.

  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. Método para la predicción del riesgo de desarrollar la enfermedad de degeneración macular asociada a la edad en la población española

    OpenAIRE

    Rodríguez de Córdoba, Santiago; Martínez-Barricarte, Rubén; García-Layana, Alfredo; Fernández-Robredo, Patricia; Recalde, Sergio; Pérez-Pérez, Julián; Olavarrieta, Leticia; Viñuela, Antonio

    2011-01-01

    Método para predecir el riesgo de desarrollar la enfermedad de degeneración macular asociada a la edad en población caucásica española que se caracteriza porque se utilizan para el cálculo marcadores genéticos prevalentes en población afectada por dicha enfermedad en relación a población sana.

  15. Clinical Practice Guidelines for Ventilation Associated Pneumonia. Guía de práctica clínica para el tratamiento de la neumonía asociada al ventilador.

    OpenAIRE

    Eddy Pereira Valdés.; Héctor Cruz de los Santos.; Belkys Rodríguez Llerena; Marcos Diosdado Iraola Ferrer.

    2009-01-01

    Clinical Practice Guidelines for Ventilation Associated Pneumonia. Conceptualized as the bacterial pneumonia that develops in patients receiving mechanical ventilation for more than 48 hours, which is not present at the beginning of the ventilation. We review the concept, prevention and treatment. It includes assessment guidelines focused on the most important aspects to be accomplished.Guía de práctica clínica para el tratamiento de la neumonía asociada al ventilador. Conceptualizada como la...

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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 ...

  4. 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 ...

  5. Killer Pigments in Bacteria: An Ecological Nightmare.

    Science.gov (United States)

    Benathen, Isaiah A.; Saccardi, Marion

    2000-01-01

    Describes an alternative to teaching ecology by using bacteria to test competitor survival. Students observe a time-dependent selective killing of other unrelated bacteria by Pseudomonas aeruginosa. (SAH)

  6. 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.

  7. 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...

  8. 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).

  9. 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.

  10. 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.

  11. 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.

  12. Box-shaped halophilic bacteria.

    OpenAIRE

    Javor, B; Requadt, C; Stoeckenius, W

    1982-01-01

    Three morphologically similar strains of halophilic, box-shaped procaryotes have been isolated from brines collected in the Sinai, Baja California (Mexico), and southern California (United States). Although the isolates in their morphology resemble Walsby's square bacteria, which are a dominant morphological type in the Red Sea and Baja California brines, they are probably not identical to them. The cells show the general characteristics of extreme halophiles and archaebacteria. They contain ...

  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. Bacteria interfere with A-actinomycetemcomitans colonization

    OpenAIRE

    Teughels, Wim; Haake, S. Kinder; Sliepen, Isabelle; Pauwels, Martine; Van Eldere, Johan; Cassiman, Jean-Jacques; Quirynen, Marc

    2007-01-01

    It is known that beneficial bacteria can suppress the emergence of pathogenic bacteria, particularly in the gastrointestinal tract. This study examined the potential for a similar suppression of Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans colonization of epithelial cells, due to its potential relevance in periodontal diseases. Seven presumed beneficial bacteria were examined for their ability to interfere, exclude, or displace A. actinomycetemcomitans from epithelial cells...

  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. Magnetotactic bacteria at the geomagnetic equator

    International Nuclear Information System (INIS)

    Magnetotatic bacteria are observed in freshwater and marine sediments of Fortaleza, Brazil, situated close to the geomagnetic equator. Both South-seeking and North-seeking bacteria are present in roughly equal numbers in the same samples. This observation is consistent with the hypothesis that the vertical component of the geomagnetic field selects the predominant polarity type among magnetotactic bacteria in natural environments. (Author)

  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. 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...

  20. 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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. 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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Infecciones del torrente sanguíneo asociadas al catéter venoso central en el servicio de cuidado intensivo neonatal

    Directory of Open Access Journals (Sweden)

    Marlen Villegas Sánchez

    2012-10-01

    Full Text Available Las bacteremias asociadas a los abcesos vasculares son una complicación grave y frecuente dentro de las infeccionesvinculadas con dispositivos vasculares. Están relacionadas con el tiempo de la cateterización y la atención recibida duranteel proceso instrumental. La mayoría de los microorganismos implicados proceden de la piel. El grupo más afectado es el delos recién nacidos; además de otros factores como el bajo peso, la edad gestacional y la inmadurez del sistema inmunológicoque los vuelve más susceptibles a adquirir enfermedades. En el servicio de Neonatología del Hospital Nacional de Niños,durante el primer semestre del 2011, un 80% de las infecciones se diagnosticaron como septicemias y, de estas, más del 50%se asoció con el uso de Catéter Venoso Central. Se formuló una pregunta en formato PICO (pacientes, intervención,comparación, observación, posteriormente se realizó una búsqueda de información en las diferentes bases de datossugeridas en el Curso de Práctica Clínica de Enfermería Basada en la Evidencia, impartido por CIEBE-CR. Se obtuvo 20artículos relacionados con el tema, 6 de los cuales fueron analizados mediante la aplicación de los criterios que estableceCASPe para contestar a la pregunta clínica. Se concluye que la aplicación de los “bundles” reduce las infecciones asociadasal catéter venoso central; además, el seguimiento diario de los dispositivos permite controlar y por lo tanto aplicar medidasde prevención en el momento oportuno.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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].

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

    Directory of Open Access Journals (Sweden)

    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.

  12. 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

  13. Turning Bacteria Suspensions into Superfluids

    Science.gov (United States)

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

    2015-07-01

    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 evidence for a low-shear Newtonian plateau characterized by a shear viscosity decreasing with concentration. In the semidilute regime, for particularly active bacteria, the suspension displays a "superfluidlike" 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.

  14. 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.

  15. Caracterización metagenómica del moviloma plasmídico de la población bacteriana asociada a alfalfa

    OpenAIRE

    López, José Luis

    2016-01-01

    A través del tiempo las bacterias, como organismos unicelulares, han localizado eficientemente en sus pequeños genomas la información necesaria para afrontar el desafío de los cambios ambientales. En términos genéticos (informativos) las bacterias han concentrado la mayoría de las funciones basales (mantenimiento, housekeeping) en sus replicones más grandes (los cromosomas) dedicando compartimientos genéticos especiales y móviles (plásmidos, islas de ADN, transposones, integrones) para divers...

  16. 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...

  17. Linking the Negative Binomial and Logarithmic Series Distributions via their Associated Series Relacionando las distribuciones binomial negativa\\ y logarítmica vía sus series asociadas

    Directory of Open Access Journals (Sweden)

    MAURICIO SADINLE

    Full Text Available The negative binomial distribution is associated to the series obtained by taking derivatives of the logarithmic series. Conversely, the logarithmic series distribution is associated to the series found by integrating the series associated to the negative binomial distribution. The parameter of the number of failures of the negative binomial distribution is the number of derivatives needed to obtain the negative binomial series from the logarithmic series. The reasoning in this article could be used as an alternative method to prove that the probability mass function of the negative binomial distribution sums to one. Finally, an interpretation of the logarithmic series distribution is given by using the presented reasoning.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 probar que la función de masa de probabilidad de la distribución binomial negativa suma uno. Finalmente, se presenta una interpretación de la distribución logarítmica usando el razonamiento planteado.

  18. Sulfur metabolism in phototrophic sulfur bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Dahl, Christiane

    2008-01-01

    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 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 of the...

  19. 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.

  20. 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 ...

  1. Utilization of xylooligosaccharides by selected ruminal bacteria.

    OpenAIRE

    Cotta, M A

    1993-01-01

    The ability of ruminal bacteria to utilize xylooligosaccharides was examined. Xylooligosaccharides were prepared by partially hydrolyzing oat spelt xylan in phosphoric acid. This substrate solution was added (0.2%, wt/vol) to a complex medium containing yeast extract and Trypticase that was inoculated with individual species of ruminal bacteria, and growth and utilization were monitored over time. All of the xylanolytic bacteria examined were able to utilize this oligosaccharide mixture as a ...

  2. QUANTATITIVE PCR ASSAY FOR MARINE BACTERIA

    OpenAIRE

    Brunk, Clifford F.

    2003-01-01

    Monitoring the bacterial flora in coastal marine waters by conventional techniques has been difficult as most of the bacteria do not readily grow on culture plates and their morphologies are virtually identical in the microscope. Molecular techniques, particularly characterizing bacteria using polymerase chain reaction (PCR) amplification of their small subunit ribosomal RNA (SSU rRNA) genes, has dramatically improved the ability to identify bacteria from environmental samples. Identificatio...

  3. Selection-Driven Gene Loss in Bacteria

    OpenAIRE

    Koskiniemi, Sanna; Sun, Song; Berg, Otto; Andersson, Dan I.

    2012-01-01

    Gene loss by deletion is a common evolutionary process in bacteria, as exemplified by bacteria with small genomes that have evolved from bacteria with larger genomes by reductive processes. The driving force(s) for genome reduction remains unclear, and here we examined the hypothesis that gene loss is selected because carriage of superfluous genes confers a fitness cost to the bacterium. In the bacterium Salmonella enterica, we measured deletion rates at 11 chromosomal positions and the fitne...

  4. Pathogenic bacteria and timing of laying

    OpenAIRE

    Moller, Anders P.; Soler, Juan J; Nielsen, J T; Galván, Ismael

    2015-01-01

    Pathogenic bacteria constitute a serious threat to viability of many organisms. Because growth of most bacteria is favored by humid and warm environmental conditions, earlier reproducers in seasonal environments should suffer less from the negative consequences of pathogenic bacteria. These relationships, and the effects on reproductive success, should be particularly prominent in predators because they are frequently exposed to pathogenic microorganisms from sick prey. Here, we presented and...

  5. 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....

  6. 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.

  7. Aplicación de redes neuronales artificiales en la modelación de la deforestación asociada a nuevos proyectos de infraestructura vial en las regiones del Nordeste y Bajo Cauca del departamento de Antioquia

    OpenAIRE

    Gómez Ossa, Luisa Fernanda

    2014-01-01

    Resumen: La deforestación tropical es un proceso continuo causado principalmente por la construcción de nuevas vías, las cuales sin una planificación ambiental adecuada contribuyen a la pérdida de biodiversidad. En la presente investigación se estimó un modelo de regresión logística y un modelo de redes neuronales artificiales (RNAs), para predecir la deforestación asociada a nuevas vías en las regiones del Bajo Cauca y Nordeste del departamento de Antioquia para el periodo 1980-2000. Se cons...

  8. 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 ...

  9. Aplicación para la grabación, obtención y reproducción de información asociada a etiquetas RFID sobre Windows Mobile 2005 en C# 2.0

    OpenAIRE

    Comas Fernández, Joan

    2009-01-01

    El objetivo principal de la aplicación es la de permitir a un usuario grabar un mensaje oral vinculado a una etiqueta RFID (1) y obtener la posible información asociada a esta etiqueta desde un sistema global, que haya podido ser introducida por un fabricante, reproduciéndola mediante un software existente de Text-To-Speech (2) (3), sobre una plataforma móvil PDA con Windows Mobile 5.0. Esta nueva herramienta está pensada para mejorar la calidad de vida y la autonomía de las personas con p...

  10. 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...

  11. OBSERVACIONES HISTOLÓGICAS DE ESTRUCTURAS CELULARES ASOCIADAS A Spongospora subterranea f sp. subterranea EN PAPA HISTOLOGY OBSERVATIONS OF CELLULAR STRUCTURES ASSOCIATED TO Spongospora subterranea f sp. subterranea IN POTATO

    OpenAIRE

    Liliana Hoyos Carvajal; Marcela Villegas Ochoa; Elena Paola González Jaimes

    2009-01-01

    Spongospora subterranea (Wallroth) Lagerheim f. sp. subterranea Tomlinson, agente causal de la sarna polvosa de la papa, es un parásito obligado el cual por sus características biológicas y reproductivas, posee una gran capacidad de sobrevivencia e infección no solo en su principal hospedero, sino también en diversas especies silvestres. El objetivo de este estudio fue realizar observaciones de estructuras celulares asociadas a S. subterranea f. sp. subterranea en plantas de papa en diferente...

  12. La lectura voluntaria de libros en el alumnado español de 10 a 18 años : diferencias territoriales, de género y características asociadas

    OpenAIRE

    Mendoza Berjano, Ramón; Batista Foguet, Joan Manuel; Rubio González, Antonia; Gómez Baya, Diego; Cruz Torres, María Carmen

    2015-01-01

    Introducción: El diseño de programas de fomento de la lectura de libros requiere conocer la interrelación entre dicho hábito y otros aspectos de los estilos de vida. Objetivos: 1) Estudiar las diferencias de género y las diferencias territoriales en la frecuencia de lectura voluntaria de libros en el alumnado español y 2) Identificar características personales y contextuales asociadas a este hábito. Método: Una muestra aleatoria y representativa del alumnado de 1...

  13. Relación de la entomofauna asociada a la descomposición de cuerpos de cerdo con el tiempo de sumersión posmortem (ISPM) en un ecosistema lentico de la sabana de Bogotá

    OpenAIRE

    Latorre Cortés, Liliana

    2010-01-01

    El objetivo principal del trabajo fue establecer el intervalo de sumersión post mortem (ISPM) empleando la entomofauna asociada a los cuerpos de cerdo; en la localidad de Usaquén de Bogotá D.C. Se seleccionaron cuatro sitios ocho días antes del inicio de la fase de campo: sitio control, sitio 1, 2, 3, colocando en estos jaulas metálicas forradas en malla que permitían el acceso de los insectos. Se sacrificaron 3 cerdos con impacto de bala en la base del cráneo y posteriormente se sumergieron ...

  14. Variables de personalidad asociadas en la dinámica bullying (agresores versus víctimas) en niños y niñas de 10 a 15 años

    OpenAIRE

    Cerezo Ramírez, Fuensanta

    2001-01-01

    El presente trabajo resume una investigación que nos permitió comprobar algunas variables de personalidad y socialización asociadas a cada una de las partes de la dinámica bullying: agresores y víctimas. Sobre una muestra de 315 escolares de 10 a 15 años, se detectaron 36 alumnos bullies y 17 víctimas mediante el cuestionario Bull (Cerezo y Esteban, 1994), estos sujetos completaron el cuestionario de personalidad EPQ-J Eysenck, el de Autoestima de Rosenberg (Ad...

  15. 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...

  16. 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...

  17. Comorbilidad asociada en un grupo de consumidores de heroína de Medellín Associated Comorbidity in a Heroin Consumer Group in the City of Medellin

    OpenAIRE

    Guillermo Alonso Castaño Pérez; Gustavo Adolfo Calderón Vallejo

    2010-01-01

    Introducción: Este artículo revisa la comorbilidad física y mental asociada con el consumo de drogas en un grupo de 42 consumidores de heroína en la ciudad de Medellín (Colombia), quienes fueron contactados en centros de tratamiento y por medio de la técnica bola de nieve. Método: Entrevistas semiestructuradas para recolectar información sobre su perfil sociodemográfico, vías de administración, prácticas de consumo, rituales, intercambio de utensilios, relaciones sexuales y protección, ideas ...

  18. 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...

  19. Incidencia y consecuencias de la traqueobronquitis asociada a ventilación mecánica en unidades de cuidados intensivos Incidence and consequences of tracheobronchitis associated with ventilator in ICUs

    OpenAIRE

    Anselmo Abdo Cuza; Roberto Castellanos-Gutiérrez; Julio César González-Aguilera; Reinaldo Reyes-Tornés; Yoleinis Vázquez-Belizón; Manuel Ernesto Somoza-García; Javier Casas-Rodríguez; Anabel Barani-Larrazabal; Adriel Viera-Paz; Alejandro Vázquez-Soto; Abel Corcho-Martínez; Carlos Roberto Valdés-Riñak; Bárbara Reigoso-Cruz; Lissette del Rosario López-González; Daysi Eduarda Álvarez-Montalvo

    2013-01-01

    Introducción: las infecciones respiratorias bajas ocupan el primer lugar entre las infecciones relacionadas con el cuidado sanitario en unidades de cuidados intensivos. Objetivos: describir la incidencia y las consecuencias, sobre estadía y mortalidad, de la traqueobronquitis asociada a ventilación mecánica (TAVM) en UCI. Métodos: estudio multricéntrico, descriptivo, prospectivo y transversal, en 6 UCI de adultos. Se estudiaron 454 pacientes. Las variables de estudio fueron recogidas en 2 bas...

  20. Factores de pronóstico relacionados con la mortalidad por neumonía asociada a ventilación mecánica Prognosis factors related to mortality due to pneumonia associated to mechanical ventilation

    OpenAIRE

    Zadis Navarro Rodríguez; Jeisa Rosa Safonts Ferrer; Yanisleidis Guibert Usatorres; Mercedes del Rosario Porto Castellanos

    2013-01-01

    Se realizó un estudio observacional, analítico y retrospectivo de 45 pacientes con neumonía asociada a ventilación mecánica, atendidos en la Unidad de Cuidados Intensivos del Hospital Provincial Docente Clinicoquirúrgico "Saturnino Lora Torres" de Santiago de Cuba, desde mayo de 2011 hasta igual mes de 2012, con vistas a identificar los factores de pronóstico relacionados con la mortalidad por esa causa. No hubo asociación estadística entre el número de muertes por neumonía y la presencia de ...

  1. Bacteria cell properties and grain size impact on bacteria transport and deposition in porous media.

    Science.gov (United States)

    Bai, Hongjuan; Cochet, Nelly; Pauss, André; Lamy, Edvina

    2016-03-01

    The simultaneous role of bacteria cell properties and porous media grain size on bacteria transport and deposition behavior was investigated in this study. Transport column experiments and numerical HYDRUS-1D simulations of three bacteria with different cell properties (Escherichia coli, Klebsiella oxytoca, and Rhodococcus rhodochrous) were carried out on two sandy media with different grain sizes, under saturated steady state flow conditions. Each bacterium was characterized by cell size and shape, cell motility, electrophoretic mobility, zeta potential, hydrophobicity and potential of interaction with the sand surface. Cell characteristics affected bacteria transport behavior in the fine sand, but similar bacteria breakthroughs and retardation factors observed in the coarse sand, indicated that bacteria transport was more depended on grain size than on bacteria cell properties. Retention decreased with increasing hydrophobicity and increased with increasing electrophoretic mobility of bacteria for both sand. The increasing sand grain size resulted in a decrease of bacteria retention, except for the motile E. coli, indicating that retention of this strain was more dependent on cell motility than on the sand grain size. Bacteria deposition coefficients obtained from numerical simulations of the retention profiles indicated that straining was an important mechanism affecting bacteria deposition of E. coli and Klebsiella sp., in the fine sand, but the attachment had the same importance as straining for R. rhodochrous. The results obtained in the coarse sand did not permit to discriminate the predominant mechanism of bacteria deposition and the relative implication of bacteria cell properties of this process. PMID:26705829

  2. Quorum sensing in gram-negative bacteria

    DEFF Research Database (Denmark)

    Wu, H.; Song, Z.J.; Høiby, N.; Givskov, Michael Christian

    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...

  3. In vitro susceptibility testing of anaerobic bacteria.

    Science.gov (United States)

    Washington, J A

    1979-01-01

    In vitro susceptibility testing of anaerobic bacteria should be limited to isolates from persistent or recurrent infections that have been treated adequately and appropriately with antimicrobial agents and, in reference centers, to collections of isolates in order to monitor alterations in susceptibility of species to various antimicrobial agents. An agar dilution reference method is being evaluated currently; however, practicality limits sporadic testing of single isolates to disk elution or broth dilution techniques. No single disk diffusion method has yet been found to be acceptable for testing anaerobic bacteria, and the results obtained with standardized procedures for aerobic and facultatively anaerobic bacteria are not applicable to anaerobic bacteria. PMID:288163

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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

  9. 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

  10. Estudio de revisión: Correlación entre consumo de sustancias psicoactivas y variables psicosociales asociadas en estudiantes universitarios

    Directory of Open Access Journals (Sweden)

    Guillermo Ceballos Ospino

    2014-01-01

    Full Text Available El presente trabajo centra su atención en la revisión y análisis de las investigaciones realizadas en torno al tema de consumo de sustancias psicoactivas (SPA y variables psicosociales asociadas. El consumo de SPA es una situación de alta prevalencia, es objeto de atención para los sectores académicos y gubernamentales de todos los países del mundo, debido a sus profundas consecuencias económicas, sociales, sanitarias, entre otras. Aportar medidas de intervención es solo posible en la medida que se conozca la magnitud y dinámicas particulares del fenómeno (en este caso variables psicosociales que promuevan un reconocimiento de todos los factores involucrados en la problemática para formular estrategias efectivas de control. En la presente revisión, se analizan diferentes investigaciones efectuadas en este tópico con el fin de aportar un producto que condensa información relevante y actualizada, útil para todos los profesionales de la salud que tienen un papel fundamental en el diseño de estrategias preventivas y de intervención.Palabras clave: Consumo de sustancias; estudiantes universitarios; factores psicosociales.Revision study: Correlation between the use of psychoactive substances and psychosocial variables associated to college students AbstractThe SPA consumption is a situation of high prevalence, it is the object of attention for academic and government sectors in all countries of the world, because of its deep economic, social and sanitary consequences among others. Provide intervention measures is only possible to the extent that the magnitude and the particular dynamics of the phenomenon is known (in this case psychosocial variables which promote a recognition of all the factors involved in the problem to develop effective control strategies. In the present revision, various investigations carried out on this topic are analyzed in order to provide a product that condenses relevant and updated information, useful

  11. 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.

  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. Sponge-associated bacteria: general overview and special aspects of bacteria associated with Halichondria panicea.

    Science.gov (United States)

    Imhoff, J F; Stöhr, R

    2003-01-01

    Increasing evidence is accumulating that highlights the important role of bacteria in bacteria-sponge associations. It appears to be equally important to analyse the specific association of bacteria with sponges, to realise the biological function of biologically active substances produced by sponge-associated bacteria, and to consider the relationship between bacteria and sponges in the search for new pharmaceutical products. In this chapter the current knowledge on bacteria-sponge associations is briefly reviewed. Results are summarised that were obtained by three major methodological approaches: (1) classical microscope observations, (2) investigations attempting to characterise sponge-associated bacteria by describing pure culture isolates, and (3) the rapidly growing evidence from genetic analyses of sponge-associated bacteria. Special emphasis is given to the evidence of possible symbiotic interactions between bacteria and sponges and to the synthesis of natural products by bacteria isolated from or associated with marine sponges. Case studies including morphological and genetic studies together with results from pure culture studies have been performed with bacteria from the sponges Rhodopaloeides odorabile, Aplysina cavernicola, and Halichondria panicea. In addition, new results on bacteria associated with Halichondria panicea are also presented. PMID:15825639

  14. 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.

  15. Rapid methods for detection of bacteria

    DEFF Research Database (Denmark)

    Corfitzen, Charlotte B.; Andersen, B.Ø.; Miller, M.; Ursin, C.; Arvin, Erik; Albrechtsen, Hans-Jørgen

    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...

  16. 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,

  17. 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...

  18. 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...

  19. Metabolismo de isoflavonas por bacterias intestinales

    OpenAIRE

    Delgado, Susana; Guadamuro, Lucía; Flórez García, Ana Belén; Mayo Pérez, Baltasar

    2014-01-01

    Trabajo presentado en la 8ª Reunión de la Red Temática BAL (Red Española de Bacterias Lácticas), "Participación de las Bacterias Lácticas en la Salud Humana y en la Calidad Alimentaria", celebrada en San Adrián (Navarra) el 25 de junio de 2014.

  20. Bacteria dispersal by hitchhiking on zooplankton

    DEFF Research Database (Denmark)

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

    2010-01-01

    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...

  1. 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

  2. Comparative genomics of the lactic acid bacteria

    Science.gov (United States)

    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 bacter...

  3. 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.

  4. 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...... 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...

  5. 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...

  6. 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.

  7. 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.

  8. Therapeutic Properties of Probiotic Bacteria

    Directory of Open Access Journals (Sweden)

    Nathanon Trachoo

    2006-01-01

    Full Text Available In spite of its long history, public consciousness of probiotics has shifted dramatically in recent years. This is due to a number of factors, including an increased concern about the potential generation of antibiotic resistant bacterial strains due to widespread antibacterial use, and also to the spreading realization that one`s health can be, not simply maintained, but actually improved with proper nutrition. Combined, these factors have stimulated a surge in probiotic research in the past decade, resulting in increasingly refined studies. Indeed, after Elie Metchnikov first printed his work suggesting a positive correlation between human longevity and the consumption of fermented milk, information on probiotics is leaving the realm of the anecdotal as recent, double-blind, placebo controlled randomized tests support beneficial probiotic activity. Concurrently, more is being learned about their activities in vivo. While much work remains to be done before a detailed understanding of probiotics can be achieved, there is mounting evidence that probiotics, when used in proper conditions, may indeed have prophylactic or preventative effects on a broad array of human and animal diseases. This article briefly surveys probiotic history and discusses recent research with a special emphasis on lactic acid bacteria probiotics. Finally, it discusses the inherent difficulties of their study and suggestions for standards for future work.

  9. Mycelial bacteria of saline soils

    Science.gov (United States)

    Zvyagintsev, D. G.; Zenova, G. M.; Oborotov, G. V.

    2008-10-01

    The actinomycetal complexes of saline soils comprise the representatives of the Streptomyces and Micromonospora genera, the number of which are hundreds and thousands of CFU/g soil. Complexes of mycelial bacteria in saline soils are poorer in terms of number (by 1-3 orders of magnitude) and taxonomic composition than the complexes of the zonal soil types. A specific feature of the actinomycetal complexes of saline soils is the predominance of halophilic, alkaliphilic, and haloalkaliphilic streptomycetes that well grow at pH 8-9 and concentrations of NaCl close to 5%. Actinomycetes in saline soils grow actively, and the length of their mycelium reaches 140 m in 1 gram of soil. The haloalkaliphilic streptomycetes grow fast and inhibit the formation of spores at pH 9 and high concentrations of salts (Na2SO4 and MgCl2, 5%) as compared to their behavior on a neutral medium with a salt concentration of 0.02%. They are characterized by the maximal radial growth rate of colonies on an alkaline medium with 5% NaCl.

  10. Comparative cytotoxicity of periodontal bacteria

    International Nuclear Information System (INIS)

    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

  11. H2 from hot bacteria

    International Nuclear Information System (INIS)

    This paper reports that a surprisingly large number of bacteria either oxidize or evolve molecular hydrogen (H2) in their natural environments. In such organisms, the reversible activation of H2 is catalyzed by an enzyme turned hydrogenase that can cause electrons provided by an electron donor with protons to evolve H2. The enzyme may oxidize H2 in the presence of a suitable electron acceptor. Hydrogenase will also catalyze an isotope exchange reaction between deuterium (D2) or tritium (T2) gas and water. Few enzymes have as many potential biotechnological applications as hydrogenase. H2 is a versatile and efficient energy carrier, considered the fuel of the future by some, and is an important intermediate in a variety of chemical and petrochemical processes. Hydrogenase has also been proposed to replace platinum in H/D and H/T separations in the nuclear power industry and to activate H2 for electrode-based processes. Indeed, H2 is considered one of the most abundant substrates for the future chemical synthesis industry and the enzyme-catalyzed production of organic chemicals from H2 and CO2 has been described. a complete understanding of how hydrogenases catalyze the reversible activation of H2 might therefore have farreaching consequences in both applied and basic research

  12. 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.

  13. 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.

  14. Bacteria classification using Cyranose 320 electronic nose

    Directory of Open Access Journals (Sweden)

    Gardner Julian W

    2002-10-01

    Full Text Available Abstract Background An electronic nose (e-nose, the Cyrano Sciences' Cyranose 320, comprising an array of thirty-two polymer carbon black composite sensors has been used to identify six species of bacteria responsible for eye infections when present at a range of concentrations in saline solutions. Readings were taken from the headspace of the samples by manually introducing the portable e-nose system into a sterile glass containing a fixed volume of bacteria in suspension. Gathered data were a very complex mixture of different chemical compounds. Method Linear Principal Component Analysis (PCA method was able to classify four classes of bacteria out of six classes though in reality other two classes were not better evident from PCA analysis and we got 74% classification accuracy from PCA. An innovative data clustering approach was investigated for these bacteria data by combining the 3-dimensional scatter plot, Fuzzy C Means (FCM and Self Organizing Map (SOM network. Using these three data clustering algorithms simultaneously better 'classification' of six eye bacteria classes were represented. Then three supervised classifiers, namely Multi Layer Perceptron (MLP, Probabilistic Neural network (PNN and Radial basis function network (RBF, were used to classify the six bacteria classes. Results A [6 × 1] SOM network gave 96% accuracy for bacteria classification which was best accuracy. A comparative evaluation of the classifiers was conducted for this application. The best results suggest that we are able to predict six classes of bacteria with up to 98% accuracy with the application of the RBF network. Conclusion This type of bacteria data analysis and feature extraction is very difficult. But we can conclude that this combined use of three nonlinear methods can solve the feature extraction problem with very complex data and enhance the performance of Cyranose 320.

  15. Antibacterial activity of aquatic gliding bacteria.

    Science.gov (United States)

    Sangnoi, Yutthapong; Anantapong, Theerasak; Kanjana-Opas, Akkharawit

    2016-01-01

    The study aimed to screen and isolate strains of freshwater aquatic gliding bacteria, and to investigate their antibacterial activity against seven common pathogenic bacteria. Submerged specimens were collected and isolated for aquatic gliding bacteria using four different isolation media (DW, MA, SAP2, and Vy/2). Gliding bacteria identification was performed by 16S rRNA gene sequencing and phylogenetic analysis. Crude extracts were obtained by methanol extraction. Antibacterial activity against seven pathogenic bacteria was examined by agar-well diffusion assay. Five strains of aquatic gliding bacteria including RPD001, RPD008, RPD018, RPD027 and RPD049 were isolated. Each submerged biofilm and plastic specimen provided two isolates of gliding bacteria, whereas plant debris gave only one isolate. Two strains of gliding bacteria were obtained from each DW and Vy/2 isolation medium, while one strain was obtained from the SAP2 medium. Gliding bacteria strains RPD001, RPD008 and RPD018 were identified as Flavobacterium anhuiense with 96, 82 and 96 % similarity, respectively. Strains RPD049 and RPD027 were identified as F. johnsoniae and Lysobacter brunescens, respectively, with similarity equal to 96 %. Only crude extract obtained from RPD001 inhibited growth of Listeria monocytogenes (MIC 150 µg/ml), Staphylococcus aureus (MIC 75 µg/ml) and Vibrio cholerae (MIC 300 µg/ml), but showed weak inhibitory effect on Salmonella typhimurium (MIC > 300 µg/ml). Gliding bacterium strain RPD008 should be considered to a novel genus separate from Flavobacterium due to its low similarity value. Crude extract produced by RPD001 showed potential for development as a broad antibiotic agent. PMID:26885469

  16. Fundamento molecular de la esteatosis hepática asociada a la obesidad Molecular basis of obesity-related hepatic steatosis

    Directory of Open Access Journals (Sweden)

    X. Buqué

    2008-09-01

    Full Text Available La enfermedad del hígado graso no alcohólico es una enfermedad inflamatoria hepática de carácter crónico de gran relevancia en la actualidad por su fuerte asociación con enfermedades de incidencia creciente como la obesidad y la diabetes mellitus tipo 2. En este trabajo se recoge buena parte del conocimiento existente sobre los mecanismos moleculares implicados en el establecimiento de la esteatosis hepática, el primer estadio de la enfermedad, y en su progreso a esteatohepatitis. Se ha prestado una atención especial al hígado graso asociado a la obesidad, clínica y experimental. En este caso, se valora la rata fa/fa, un modelo animal de obesidad con rasgos fenotípicos similares a los de la obesidad humana, incluyendo la resistencia a la insulina y la dislipemia. La esteatosis hepática se revela como una situación compleja, eminentemente metabólica, en la que se simultanean procesos metabólicos aparentemente contradictorios, así como estrés oxidativo, estrés de retículo endoplasmático, disfunción mitocondrial y descenso en la expresión de genes de supervivencia. En buena medida, en su base se sitúan señales extrahepáticas, como las producidas en una situación de resistencia periférica a la insulina asociada a un aumento de la masa adiposa y de ácidos grasos libres sistémicos, e internas, causantes de un desajuste de las funciones glucostática y lipidostática del hígado y de una mayor vulnerabilidad a otras agresiones.Non-alcoholic fatty liver disease is a chronic inflammation liver condition that is currently highly relevant because of its strong association with increasingly incident diseases such as obesity and type-2 diabetes mellitus. The primary purpose of this paper is to discuss the best part of current knowledge on the molecular mechanisms involved in hepatic steatosis development, the condition's initial stage, and on progression to steatohepatitis. Special attention has been paid to clinical and

  17. 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

  18. 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

  19. Glomerulonefritis aguda post-infecciosa asociada a neumonía neumocócica Acute post infectious glomerulonephritis associated to pneumococcal pneumonia

    Directory of Open Access Journals (Sweden)

    S. Fernández de Miguel

    2009-01-01

    Full Text Available

    Presentamos un niño de 6 años con insuficiencia renal aguda secundaria a glomerulonefritis asociada a neumonía neumocócica. El paciente presentó en primer lugar un síndrome nefrítico con hematuria, proteinuria, oliguria, edemas y deterioro de la función renal, siendo diagnosticado a continuación de neumonía con derrame pleural. La función renal se normalizó tras 72 horas, persistiendo una hipertensión arterial que precisó tratamiento en la fase aguda. El cuadro se resolvió sin secuelas. Asimismo, revisamos la información
    publicada previamente sobre casos similares en la literatura científica. El caso sirve para reforzar el concepto de que otros microorganismos además del Streptococcus pyogenes pueden desencadenar una glomerulonefritis post-infecciosa y deben considerarse en el diagnóstico diferencial de cualquier niño que presente glomerulonefritis aguda y hallazgos respiratorios.
    La presentación del cuadro nefrítico suele ser concomitante o con poca latencia respecto al cuadro infeccioso. A nivel analítico se encontró un descenso de la fracción C3 del complemento y un aumento del título de antiestreptolisinas, como se ha descrito en otras publicaciones. La etiología se confirmó mediante detección del antígeno neumocócico en orina y líquido pleural. La evolución del cuadro nefrítico suele ser buena, como en nuestro caso, y es excepcional que se precise algún método de depuración extrarrenal.

    We report a 6 year old boy, evolving acute renal failure due to acute glomerulonephritis associated with pneumonia. The patient firstly presented a nephritic syndrome with abnormal urinalysis, hypertension, azotemia and oliguria, being diagnosed afterwards of pneumonia. Renal function was normal past 72 hours. He presented arterial hypertension that required treatment only in acute phase.
    This case was resolved with no after-effects. Previously released information about similar cases in

  20. 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 ...

  1. 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.

  2. 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.

  3. Magnetotactic Bacteria from Extreme Environments

    Science.gov (United States)

    Bazylinski, Dennis A.; Lefèvre, Christopher T.

    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 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. PMID:25369742

  4. 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.

  5. 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.

  6. Effects of thermoradiation on bacteria

    International Nuclear Information System (INIS)

    A 60Co source was used to determine the effects of thermoradiation on Achromobacter aquamarinus, Staphylococcus aureus, and vegetative and spore cells of Bacillus subtilis var. globigii. The rate of inactivation of these cultures, except vegetative-cell populations of B. subtilis, was exponential and in direct proportion to temperature. The D10 (dose that inactivates 90 percent of the microbial population) value for A. aquamarinus was 8.0 Krad at 25 degrees C and 4.9 Krad at 35 degrees C. For S. aureus, D10 was 9.8 and 5.3 Krad at 35 and 45 degrees C, respectively. Vegetative cells of B. subtilis demonstrated a rapid initial inactivation followed by a steady but decreased exponential rate. The D10 at 25 degrees C was 10.3 Krad, but at 35 and 45 degrees C this value was 6.2 and 3.8 Krad, respectively. Between 0 and 95 Krad, survival curves for B. subtilis spores at 75 degrees C showed slight inactivation, increasing in rat at and above 85 degrees C. The D10 values for spores at 85 and 90 degrees C were 129 and 92 Krad, respectively. Significant synergism between heat and irradiation was noted at 35 degrees C for A. aquamarinus and 45 degrees C for S. aureus. The presence of 0.1 mM cysteine in suspending media afforded protection to both cultures at these critical temperatures. On the other hand, cysteine sensitized B. subtilis spores at radiation doses greater than 100 Krad. The combined effect of heat and irradiation was more destructive to bacteria than either method alone

  7. Clustering of Marine Bacteria in Seawater Enrichments

    OpenAIRE

    Mitchell, J.G.; Pearson, L; Dillon, S.

    1996-01-01

    Seawater enrichments of marine bacteria clustered in 20- to 50-(mu)m-wide bands near air-water interfaces. The cells within the band travelled at up to 212 (mu)m s(sup-1) and at an average speed of 163 (mu)m s(sup-1). Mean cell speeds peaked mid-run at 187 (mu)m s(sup-1). At the end of the run, bacteria reversed direction rather than randomly reorienting. The duration of the stops during reversal was estimated at 18 ms, six to seven times shorter than that found in enteric bacteria. Cells hun...

  8. 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....

  9. Acidophilic, Heterotrophic Bacteria of Acidic Mine Waters

    OpenAIRE

    Wichlacz, Paul L.; Unz, Richard F.

    1981-01-01

    Obligately acidophilic, heterotrophic bacteria were isolated both from enrichment cultures developed with acidic mine water and from natural mine drainage. The bacteria were grouped by the ability to utilize a number of organic acids as sole carbon sources. None of the strains were capable of chemolithotrophic growth on inorganic reduced iron and sulfur compounds. All bacteria were rod shaped, gram negative, nonencapsulated, motile, capable of growth at pH 2.6 but not at pH 6.0, catalase and ...

  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. 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.

  12. DECONTAMINATION OF HEAVY METALS WITH BACTERIA

    Science.gov (United States)

    OBJECTIVES: To discover, improve, understand the mechanisms and use naturally occurring bacteria to decontiminate in situ heavy metals from the soils, sediments and waters to protect human health and the environment. ABSTRACT: Our laboratory (Vesper et al. ...

  13. 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...

  14. 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 ...

  15. Effect of leukocyte hydrolases on bacteria

    International Nuclear Information System (INIS)

    Leukocyte extracts, trypsin, and lysozyme are all capable of releasing the bulk of the LPS from S. typhi, S. typhimurium, and E. coli. Bacteria which have been killed by heat, ultraviolet irradiation, or by a variety of metabolic inhibitors and antibiotics which affect protein, DNA, RNA, and cell wall synthesis no longer yield soluble LPS following treatment with the releasing agents. On the other hand, bacteria which are resistant to certain of the antibiotics yield nearly the full amount of soluble LPS following treatment, suggesting that certain heatabile endogenous metabolic pathways collaborate with the releasing agents in the release of LPS from the bacteria. It is suggested that some of the beneficial effects of antibiotics on infections with gram-negative bacteria may be the prevention of massive release of endotoxin by leukocyte enzymes in inflammatory sites

  16. Electrical Cable Bacteria Save Marine Life

    DEFF Research Database (Denmark)

    Nielsen, Lars Peter

    2016-01-01

    Animals at the bottomof 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 bottomof 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....

  17. 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....

  18. 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,...

  19. 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 ...

  20. Magnetization processes in magnetotactic bacteria systems

    Czech Academy of Sciences Publication Activity Database

    Polyakova, T.; Zablotskyy, Vitaliy A.

    2005-01-01

    Roč. 293, - (2005), s. 365-370. ISSN 0304-8853. [International Conference on Scientific and Clinical Aplications of Magnetic Carriers. Lyon, 20.05.04-22.05.04] Grant ostatní: MCF: Nanomag-Lab(XE) N 2004-003177 Institutional research plan: CEZ:AV0Z10100520 Keywords : magnetotactic bacteria * magnetization process * chemotaxis * bacteria * magnetosomes * chain formation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.985, year: 2005

  1. 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 (...

  2. 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...

  3. 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...

  4. Bacteria under SOS evolve anticancer phenotypes

    OpenAIRE

    Weitao Tao; Dallo Shatha F

    2010-01-01

    Abstract Background The anticancer drugs, such as DNA replication inhibitors, stimulate bacterial adhesion and induce the bacterial SOS response. As a variety of bacterial mutants can be generated during SOS, novel phenotypes are likely to be selected under the drug pressure. Presentation of the hypothesis Bacteria growing with cancer cells in the presence of the replication inhibitors undergo the SOS response and evolve advantageous phenotypes for the bacteria to invade the cancer cells in o...

  5. Characterization of (per)chlorate-reducing bacteria

    OpenAIRE

    Wolterink, A.F.W.M.

    2004-01-01

    Some bacteria can use (per)chlorateas terminal electron acceptor for growth. These bacteria convert perchlorate via chlorate and chlorite into chloride and molecular oxygen. Oxygen formation in microbial respiration is unique. In this study two chlorate-reducing strains belonging to the species Pseudomonas chloritidismutans and a (per)chlorate-reducing strain Dechloromonas hortensis were isolated. The characterization of the chlorate-reducing strain AW-1, which was isolated from a bioreactor ...

  6. 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.

  7. Quorum sensing mechanism in lactic acid bacteria

    OpenAIRE

    Hatice Yılmaz - Yıldıran; Aynur Gül Karahan; Gülden Başyiğit - Kılıç

    2015-01-01

    For a long time, microorganisms were considered as just multiplying, finding nutrients and living by themselves organisms. But that belief changed 50 years ago along with the discovery of bacteria communication with each other and environment by microbiologists. The language used in the communication consists of signal molecules and these molecules are generally called 'auto inducer'. Bacteria are capable of measuring density of these molecules and by this way they are able to detect amoun...

  8. Molecular Evolution of Threonine Dehydratase in Bacteria

    OpenAIRE

    Yu, Xuefei; Li, Ye; Wang, Xiaoyuan

    2013-01-01

    Threonine dehydratase converts L-threonine to 2-ketobutyrate. Several threonine dehydratases exist in bacteria, but their origins and evolutionary pathway are unknown. Here we analyzed all the available threonine dehydratases in bacteria and proposed an evolutionary pathway leading to the genes encoding three different threonine dehydratases CTD, BTD1 and BTD2. The ancestral threonine dehydratase might contain only a catalytic domain, but one or two ACT-like subdomains were fused during the e...

  9. 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...

  10. 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

  11. Distribution of coliform bacteria in waste water

    OpenAIRE

    Dau Lal Bohra; Vikas Modasiya; Chandan Kumar Bahura

    2012-01-01

    Biological activity of water can be apparently judged by the colonization of bacteria (microbes). In order to find out the extent of pollution and the relationship between inorganic matters and microbiota, a quantitative and qualitative analysis of bacteria in various types of sewage waters, namely sewage water by the residential colonies (group I), industrial waste water (group II), sewage treatment hub (group III), unorganized collected waste water (group IV) and old residential waste colle...

  12. Horizontal gene transfer between bacteria and animals

    OpenAIRE

    Dunning Hotopp, Julie C.

    2011-01-01

    Horizontal gene transfer is increasingly described between bacteria and animals. Such transfers that are vertically inherited have the potential to influence the evolution of animals. One classic example is the transfer of DNA from mitochondria and chloroplasts to the nucleus after the acquisition of these organelles by eukaryotes. Even today, many of the described instances of bacteria to animal transfer occur as part of intimate relationships like those of endosymbionts and their invertebra...

  13. 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...

  14. 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.

  15. 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.

  16. How methylglyoxal kills bacteria: An ultrastructural study.

    Science.gov (United States)

    Rabie, Erika; Serem, June Cheptoo; Oberholzer, Hester Magdalena; Gaspar, Anabella Regina Marques; Bester, Megan Jean

    2016-01-01

    Antibacterial activity of honey is due to the presence of methylglyoxal (MGO), H2O2, bee defensin as well as polyphenols. High MGO levels in manuka honey are the main source of antibacterial activity. Manuka honey has been reported to reduce the swarming and swimming motility of Pseudomonas aeruginosa due to de-flagellation. Due to the complexity of honey it is unknown if this effect is directly due to MGO. In this ultrastructural investigation the effects of MGO on the morphology of bacteria and specifically the structure of fimbriae and flagella were investigated. MGO effectively inhibited Gram positive (Bacillus subtilis; MIC 0.8 mM and Staphylococcus aureus; MIC 1.2 mM) and Gram negative (P. aeruginosa; MIC 1.0 mM and Escherichia coli; MIC 1.2 mM) bacteria growth. The ultrastructural effects of 0.5, 1.0 and 2 mM MGO on B. substilis and E. coli morphology was then evaluated. At 0.5 mM MGO, bacteria structure was unaltered. For both bacteria at 1 mM MGO fewer fimbriae were present and the flagella were less or absent. Identified structures appeared stunted and fragile. At 2 mM MGO fimbriae and flagella were absent while the bacteria were rounded with shrinkage and loss of membrane integrity. Antibacterial MGO causes alterations in the structure of bacterial fimbriae and flagella which would limit bacteria adherence and motility. PMID:26986806

  17. Peptide conversations in Gram-positive bacteria.

    Science.gov (United States)

    Monnet, Véronique; Juillard, Vincent; Gardan, Rozenn

    2016-05-01

    Within Gram-positive bacteria, the expression of target genes is controlled at the population level via signaling peptides, also known as pheromones. Pheromones control a wide range of functions, including competence, virulence, and others that remain unknown. Until now, their role in bacterial gene regulation has probably been underestimated; indeed, bacteria are able to produce, by ribosomal synthesis or surface protein degradation, an extraordinary variety of peptides which are released outside bacteria and among which, some are pheromones that mediate cell-to-cell communication. The review aims at giving an updated overview of these peptide-dependant communication pathways. More specifically, it follows the whole peptide circuit from the peptide production and secretion in the extracellular medium to its interaction with sensors at bacterial surface or re-import into the bacteria where it plays its regulation role. In recent years, as we have accumulated more knowledge about these systems, it has become apparent that they are more complex than they first appeared. For this reason, more research on peptide-dependant pathways is needed to develop new strategies for controlling functions of interest in Gram-positive bacteria. In particular, such research could lead to alternatives to the use of antibiotics against pathogenic bacteria. In perspective, the review identifies new research questions that emerge in this field and that have to be addressed. PMID:25198780

  18. Molecular probe technology detects bacteria without culture

    Directory of Open Access Journals (Sweden)

    Hyman Richard W

    2012-03-01

    Full Text Available Abstract Background Our ultimate goal is to detect the entire human microbiome, in health and in disease, in a single reaction tube, and employing only commercially available reagents. To that end, we adapted molecular inversion probes to detect bacteria using solely a massively multiplex molecular technology. This molecular probe technology does not require growth of the bacteria in culture. Rather, the molecular probe technology requires only a sequence of forty sequential bases unique to the genome of the bacterium of interest. In this communication, we report the first results of employing our molecular probes to detect bacteria in clinical samples. Results While the assay on Affymetrix GenFlex Tag16K arrays allows the multiplexing of the detection of the bacteria in each clinical sample, one Affymetrix GenFlex Tag16K array must be used for each clinical sample. To multiplex the clinical samples, we introduce a second, independent assay for the molecular probes employing Sequencing by Oligonucleotide Ligation and Detection. By adding one unique oligonucleotide barcode for each clinical sample, we combine the samples after processing, but before sequencing, and sequence them together. Conclusions Overall, we have employed 192 molecular probes representing 40 bacteria to detect the bacteria in twenty-one vaginal swabs as assessed by the Affymetrix GenFlex Tag16K assay and fourteen of those by the Sequencing by Oligonucleotide Ligation and Detection assay. The correlations among the assays were excellent.

  19. 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 ...

  20. Antioxidant activity of Sphaerococcus coronopifolius associated bacteria

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    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.

  1. 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.

  2. Efectos del huracán "Pauline" (1997) sobre la fauna asociada a la planta Eichhornia crassipes en la Laguna Coyuca, Pacífico Sur de México

    OpenAIRE

    Ramiro Román-Contreras; Arturo Rocha-Ramírez; Sergio Cházaro-Olvera

    2008-01-01

    Observaciones sobre los efectos que el huracán "Pauline" produjo a su paso por la laguna Coyuca, sur del Pacífico de México la madrugada del 9 de octubre de 1997, indican que el disturbio tropical ocasionó en el área la desaparición temporal de la fauna asociada a las raíces del lirio acuático en relación a la fauna registrada durante los meses anteriores al fenómeno; durante los tres meses posteriores se registró la disminución de E. crassipes en el área de estudio. En enero de 1998 se obser...

  3. Puesta a punto de un modelo de rinosinusitis crónica asociada a poliposis nasal monitorizado mediante técnicas de análisis de imágenes micro CT-PET

    OpenAIRE

    RIUS ROCABERT, SERGIO

    2015-01-01

    [ES] La rinosinusitis es un proceso inflamatorio que afecta a la cavidad y senos nasales obstruyéndolos. Se denomina rinosinusitis crónica (RSC) cuando la enfermedad perdura más allá de las 12 semanas. La RSC puede verse asociada a pólipos nasales (RSC-PN) o no (RSC-SP), siendo la poliposis nasal una enfermedad con una morbilidad muy alta caracterizada por la existencia de estructuras neoplásicas que provocan la obstrucción de las vías aéreas. Los pólipos están formados por el infiltrado de c...

  4. 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

  5. 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

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    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.

  6. 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.

  7. 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.

  8. 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.

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

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    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.

  10. Magnetosome chain superstructure in uncultured magnetotactic bacteria

    International Nuclear Information System (INIS)

    Magnetotactic bacteria produce magnetosomes, which are magnetic particles enveloped by biological membranes, in a highly controlled mineralization process. Magnetosomes are used to navigate in magnetic fields by a phenomenon called magnetotaxis. Two levels of organization and control are recognized in magnetosomes. First, magnetotactic bacteria create a spatially distinct environment within vesicles defined by their membranes. In the vesicles, the bacteria control the size, composition and purity of the mineral content of the magnetic particles. Unique crystal morphologies are produced in magnetosomes as a consequence of this bacterial control. Second, magnetotactic bacteria organize the magnetosomes in chains within the cell body. It has been shown in a particular case that the chains are positioned within the cell body in specific locations defined by filamentous cytoskeleton elements. Here, we describe an additional level of organization of the magnetosome chains in uncultured magnetotactic cocci found in marine and freshwater sediments. Electron microscopy analysis of the magnetosome chains using a goniometer showed that the magnetic crystals in both types of bacteria are not oriented at random along the crystal chain. Instead, the magnetosomes have specific orientations relative to the other magnetosomes in the chain. Each crystal is rotated either 60°, 180° or 300° relative to their neighbors along the chain axis, causing the overlapping of the (1 1 1) and (1-bar 1-bar 1-bar) capping faces of neighboring crystals. We suggest that genetic determinants that are not present or active in bacteria with magnetosomes randomly rotated within a chain must be present in bacteria that organize magnetosomes so precisely. This particular organization may also be used as an indicative biosignature of magnetosomes in the study of magnetofossils in the cases where this symmetry is observed

  11. 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...

  12. 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.

  13. Bacteria and plutonium in marine environments

    International Nuclear Information System (INIS)

    Microbes are important in geochemical cycling of many elements. Recent reports emphasize biogenous particulates and bacterial exometabolites as controlling oceanic distribution of plutonium. Bacteria perform oxidation/reduction reactions on metals such as mercury, nickel, lead, copper, and cadmium. Redox transformations or uptake of Pu by marine bacteria may well proceed by similar mechanisms. Profiles of water samples and sediment cores were obtained along the continental shelf off Nova Scotia and in the Gulf of St. Lawrence. Profiles of water samples, and sediment cores were obtained. Epifluorescent microscopy was used to view bacteria (from water or sediment) after concentration on membrane filters and staining with acridine orange. Radiochemical analyses measured Pu in sediments and water samples. Studies of 237Pu uptake used a strain of Leucothrix mucor isolated from a macroalga. Enumeration shows bacteria to range 104 to 105 cells/ml in seawater or 107 to 108 cells/gram of sediment. These numbers are related to the levels and distrbution of Pu in the samples. In cultures of L. mucor amended with Pu atom concentrations approximating those present in open ocean environments, bacterial cells concentrated 237Pu slower and to lower levels than did clay minerals, glass beads, or phytoplankton. These data further clarify the role of marine bacteria in Pu biogeochemistry

  14. 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

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

    Institute of Scientific and Technical Information of China (English)

    DAI Yongding; SONG Haiming; SHEN Jiying

    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.

  16. Inhibition of seafood-borne bacteria in cooked mackerel (Rastrelliger kanagurta) fish meat by lactic acid bacteria

    OpenAIRE

    Kanappan, S.; G. Gopikrishna

    2008-01-01

    Antagonistic activity of lactic acid bacteria (LAB) namely Streptococcus faecalis, Pediococcus cerevisiae and Lactobacillus casei was tested against seafood-borne bacteria such as Staphylococcus aureus, Bacillus cereus, Escherichia coli, Clostridium perfringens and Listeria monocytogenes. Three lactic acid bacteria such as Streptococcus faecalis, Lactobacillus casei and Pediococcus cerevisiae were coated on cooked mackerel meat, individually and in combination against fish-borne bacteria. S. ...

  17. 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.

  18. Applications of Magnetosomes Synthesized by Magnetotactic Bacteria in Medicine

    OpenAIRE

    EdouardAlphandéry

    2014-01-01

    Magnetotactic bacteria belong to a group of bacteria that synthesize iron oxide nanoparticles covered by biological material that are called magnetosomes. These bacteria use the magnetosomes as a compass to navigate in the direction of the earth’s magnetic field. This compass helps the bacteria to find the optimum conditions for their growth and survival. Here, we review several medical applications of magnetotactic bacteria and magnetosomes, such as those in magnetic resonance imaging (MRI),...

  19. 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 ...

  20. Quantification and Qualification of Bacteria Trapped in Chewed Gum

    OpenAIRE

    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 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-...

  1. 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

  2. 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

  3. 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.

  4. Modulating immune responses with probiotic bacteria.

    Science.gov (United States)

    Matsuzaki, T; Chin, J

    2000-02-01

    For many years, probiotic bacteria have been known to confer health benefits to the consumer. One possible mechanism for this may be the ability of probiotic bacteria to modulate immune responses. Oral administration of Lactobacillus casei strain Shirota (LcS) has been found to enhance innate immunity by stimulating the activity of splenic NK cells. Oral feeding with killed LcS was able to stimulate the production of Th1 cytokines, resulting in repressed production of IgE antibodies against Ovalbumin in experimental mice. The ability to switch mucosal immune responses towards Th1 with probiotic bacteria provides a strategy for treatment of allergic disorders. Growth of Meth A tumour cells in the lungs was also inhibited by intrapleural injection of LcS. Oral administration of other probiotic bacteria, such as Streptococcus thermophilus (St), Lactobacillus fermentum (Lf) and yeast (Y), elicited different immune responses. Mice that were prefed yeast or Lf followed by feeding with ovalbumin (OVA) responded better to vaccination with OVA than mice not given either probiotic or OVA or mice that had been prefed only OVA. However, antibody responses were significantly suppressed in response to vaccination with OVA in mice that had been prefed yeast followed by yeast and OVA as well as mice prefed Lf followed by Lf and OVA. Prefeeding St followed by OVA feeding enhanced cellular immune responses against ovalbumin. In contrast, mice prefed St followed by St + OVA were hyporesponsive against OVA. While antigen feeding alone appears to prime for an immune response, cofeeding antigen with probiotic bacteria can suppress both antibody and cellular immune responses and may provide an efficacious protocol to attenuate autoimmune diseases, such as experimental allergic encephalomyelitis, by jointly dosing with myelin basic protein and probiotic bacteria. PMID:10651931

  5. 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.

  6. 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....

  7. Degradation of monomethylhydrazine by two soil bacteria

    International Nuclear Information System (INIS)

    It has been reported that three heterotrophic soil bacteria had the capacity to degrade hydrazine. One of these organisms, Achromobacter sp., degraded hydrazine to N2 gas. Furthermore, it was reported that monomethylhydrazine (MMH) in Arredondo fine sand was mineralized to CO2, and that such degradation is microbial. However, microorganisms that degrade MMH have not been reported. MMH and hydrazine are chemically similar to one another. Therefore, this study was initiated to test the capacity of the two hydrazine-degrading bacteria, Achromobacter sp. and Pseudomonas sp., to degrade MMH

  8. Bacterial biofilms. Bacteria Quorum sensing in biofilms

    Directory of Open Access Journals (Sweden)

    E. S. Vorobey

    2012-03-01

    Full Text Available 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 molecules of the Quorum sensing system. Coordination of bacterial cells activity in the biofilms gives them significant advantages: in the biofilms bacteria are protected from the influence of the host protective factors and the antibacterial drugs.

  9. 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?.

  10. 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

  11. 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.

  12. 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...

  13. 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

  14. 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.

  15. 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

  16. Heterotrophic bacteria in drinking water distribution system: a review.

    Science.gov (United States)

    Chowdhury, Shakhawat

    2012-10-01

    The microbiological quality of drinking water in municipal water distribution systems (WDS) depends on several factors. Free residual chlorine and/or chloramines are typically used to minimize bacterial recontamination and/or regrowth in WDS. Despite such preventive measures, regrowth of heterotrophic (HPC) and opportunistic bacteria in bulk water and biofilms has yet to be controlled completely. No approach has shown complete success in eliminating biofilms or HPC bacteria from bulk water and pipe surfaces. Biofilms can provide shelter for pathogenic bacteria and protect these bacteria from disinfectants. Some HPC bacteria may be associated with aesthetic and non-life threatening diseases. Research to date has achieved important success in understanding occurrence and regrowth of bacteria in bulk water and biofilms in WDS. To achieve comprehensive understanding and to provide efficient control against bacteria regrowth, future research on bacteria regrowth dynamics and their implications is warranted. In this study, a review was performed on the literature published in this area. The findings and limitations of these papers are summarized. Occurrences of bacteria in WDS, factors affecting bacteria regrowth in bulk water and biofilms, bacteria control strategies, sources of nutrients, human health risks from bacterial exposure, modelling of bacteria regrowth and methods of bacteria sampling and detection and quantification are investigated. Advances to date are noted, and future research needs are identified. Finally, research directions are proposed to effectively control HPC and opportunistic bacteria in bulk water and biofilms in WDS. PMID:22076103

  17. Antimicrobial resistant bacteria in the food chain

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar

    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 to...

  18. 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.

  19. 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

  20. 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...

  1. 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...

  2. 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.

  3. [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

  4. 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 ...

  5. DISTRIBUTION OF PLASMIDS IN GROUNDWATER BACTERIA

    Science.gov (United States)

    Bacteria isolated from groundwater aquifer core materials of pristine aquifers at Lula and Pickett, Oklahoma, and from a site with a history of aromatic hydrocarbon contamination and natural renovation located at Conroe, Texas, were screened for the presence of plasmid Deoxyribon...

  6. Radiographic markers - A reservoir for bacteria?

    International Nuclear Information System (INIS)

    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.

  7. The effects of bacteria on crystalline rock

    International Nuclear Information System (INIS)

    Many reactions involving inorganic minerals at water-rock interfaces have now been recognized to be bacterially mediated; these reactions could have a significant effect in the excavation of vaults for toxic and radioactive waste disposal. To investigate the role that bacteria play in the natural aqueous environment of crystalline rock the microbial growth factors of nutrition, energy and environment are described. Microbial activity has been investigated in Atomic Energy of Canada's Underground Research Laboratory (URL), situated in the Archean granitic Lac du Bonnet Batholith, Winnipeg, Manitoba. Faults, initiated in the Early Proterozoic, and later-formed fractures, provide ground-water pathways. Planktonic bacteria, free-swimming in the groundwater, have been observed in over 100 underground borehole samples. The number of bacteria varied from 103 to 105 mL-1 and appeared to decrease with depth and with increased salinity of the water. However, in the natural environment of deep (100-500 m) crystalline rocks, where nutrition is limited, formation of biofilms by sessile bacteria is a successful survival strategy. Natural biofilms at the URL and biofilms grown in bioreactors have been studied. The biofilms can accumulate different elements, depending upon the local environment. Precipitates of iron have been found in all the biofilms studied, where they are either passively accumulated or utilized as an energy source. Within the biofilm active and extensive biogeochemical immobilization of dissolved elements is controlled by distinct bacterial activities which are sufficiently discrete for hematite and siderite to be precipitated in close proximity

  8. 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...

  9. 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...

  10. Serpins in unicellular Eukarya, Archaea, and Bacteria:

    DEFF Research Database (Denmark)

    Roberts, T.H.; Hejgaard, Jørn; Saunders, N.F.W; Cavicchiolo, R.; Curmi, P.M.G

    2004-01-01

    , where serpins were found in only 4 of 13 genera, and Bacteria, in only 9 of 56 genera. The serpins from unicellular organisms appear to be phylogenetically distinct from all of the clades of higher eukaryotic serpins. Most of the sequences from unicellular organisms have the characteristics of...

  11. Molecular evolution in bacteria: cell division

    OpenAIRE

    Trevors J.T.

    1998-01-01

    Molecular evolution in bacteria is examined with an emphasis on the self-assembly of cells capable of primitive division and growth during early molecular evolution. Also, the possibility that some type of encapsulation structure preceeded biochemical pathways and the assembly of genetic material is examined. These aspects will be considered from an evolutionary perspective.

  12. 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...

  13. 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

  14. 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

  15. Identification of bacteria using mass spectrometry techniques

    Czech Academy of Sciences Publication Activity Database

    Krásný, Lukáš; Hynek, R.; Hochel, I.

    2013-01-01

    Roč. 353, NOV 2013 (2013), s. 67-79. ISSN 1387-3806 R&D Projects: GA ČR GAP503/10/0664 Institutional support: RVO:61388971 Keywords : Mass spectrometry * Bacteria * Identification Subject RIV: EE - Microbiology, Virology Impact factor: 2.227, year: 2013

  16. Chitinolytic bacteria of the mammal digestive tract

    Czech Academy of Sciences Publication Activity Database

    Šimůnek, Jiří; Hodrová, Blanka; Bartoňová, H.; Kopečný, Jan

    2001-01-01

    Roč. 46, č. 1 (2001), s. 76-78. ISSN 0015-5632 R&D Projects: GA ČR GA525/00/0984; GA AV ČR KSK5052113 Keywords : chitinolytic bacteria Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.776, year: 2001

  17. 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.

  18. Probiotic Bacteria May Become Dormant during Storage

    OpenAIRE

    Lahtinen, Sampo J.; Gueimonde, Miguel; Ouwehand, Arthur C; Reinikainen, Johanna P.; Salminen, Seppo J.

    2005-01-01

    The determination of bacterial viability in probiotic products is of economic, technological, and clinical significance. We compared four methods to enumerate three Bifidobacterium strains in fermented oat products during storage. A subpopulation of nonculturable cells retained a functional cell membrane typical of viable cells, indicating that probiotic bacteria become dormant during storage.

  19. 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. PMID:25428024

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. Bacteria in Crude Oil Survived Autoclaving and Stimulated Differentially by Exogenous Bacteria

    OpenAIRE

    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 ...

  5. 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...

  6. 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...

  7. Assessment of the Levels of Airborne Bacteria, Gram-Negative Bacteria, and Fungi in Hospital Lobbies

    OpenAIRE

    Dong-Uk Park; Jeong-Kwan Yeom; Won Jae Lee; Kyeong-Min Lee

    2013-01-01

    Aims: We assessed the levels of airborne bacteria, Gram-negative bacteria (GNB), and fungi in six hospital lobbies, and investigated the environmental and hospital characteristics that affected the airborne microorganism levels. Methods: An Andersen single-stage sampler equipped with appropriate nutrition plate agar was used to collect the samples. The three types of microorganisms were repeatedly collected at a fixed location in each hospital (assumed to be representative of the entire hospi...

  8. Pancreatitis autoinmune asociada a fibrosis retroperitoneal: evolución tras dos años de seguimiento Autoimmune pancreatitis associated with retroperitoneal fibrosis: outcome after 24 months of follow-up

    Directory of Open Access Journals (Sweden)

    M. Romero

    2008-10-01

    Full Text Available Introducción: la pancreatitis autoinmune es un tipo de pancreatitis crónica caracterizado por un infiltrado linfoplasmocitario y una elevación de IgG e IgG4, que se ha descrito asociada a diversas manifestaciones extrapancreáticas y enfermedades autoinmunes, lo cual apoya la teoría de un mecanismo autoinmune fisiopatólogico de base. Caso clínico: presentamos el caso de un varón que debutó simultáneamente con una pancreatitis autoinmune asociada a fibrosis retroperitoneal y lesión de la vía biliar extrapancreática, con respuesta total tras tratamiento con corticoides durante 4 meses y ausencia de recurrencia tras 24 meses de seguimiento. Discusión: la pancreatitis autoinmune es un tipo de pancreatitis crónica que probablemente forme parte de un proceso sistémico autoinmune, cuyas manifestaciones extrapancreáticas más frecuentes son la fibrosis retroperitoneal y las lesiones de la vía biliar extrapancreática. Su correcto diagnóstico e inicio precoz del tratamiento puede favorecer la resolución completa de las lesiones, principalmente en los casos de bajo grado de actividad, con menor probabilidad de recurrencia.Introduction: autoimmune pancreatitis is a kind of chronic pancreatitis characterized by the presence of lymphoplasmacytic infiltration and severely elevated serum IgG and IgG4, which has been associated to many extrapancreatic lesions and other autoimmune disorders, leading to the theory of an autoimmune mechanism involved in the pathogenesis of this disease. Case report: we report the case of a man who simultaneously presented with autoimmune pancreatitis associated with retroperitonal fibrosis, and a lesion of the extrapancreatic bile duct, with total response to corticosteroid treatment for 4 moths and absence of recurrence after 24 months of follow-up. Discussion: autoimmune pancreatitis is a kind of chronic pancreatitis that is probably a part of a systemic autoinmune disease, with retroperitoneal fibrosis and

  9. Comorbilidad asociada en un grupo de consumidores de heroína de Medellín Associated Comorbidity in a Heroin Consumer Group in the City of Medellin

    Directory of Open Access Journals (Sweden)

    Guillermo Alonso Castaño Pérez

    2010-02-01

    Full Text Available Introducción: Este artículo revisa la comorbilidad física y mental asociada con el consumo de drogas en un grupo de 42 consumidores de heroína en la ciudad de Medellín (Colombia, quienes fueron contactados en centros de tratamiento y por medio de la técnica bola de nieve. Método: Entrevistas semiestructuradas para recolectar información sobre su perfil sociodemográfico, vías de administración, prácticas de consumo, rituales, intercambio de utensilios, relaciones sexuales y protección, ideas e intentos suicidas, antecedentes familiares y personales de enfermedad y presencia de morbilidad física y mental. Resultados: Dichos consumidores son predominantemente hombres, solteros, con edades entre los 18 y los 23 años, sin hijos y muchos con estudios universitarios que aún no terminan. Mayoritariamente se ubican en un estrato socioeconómico medio y tienen antecedentes familiares de consumo de sustancias psicoactivas. Todos presentan historia de policonsumo de sustancias psicoactivas. Los consumidores comparten jeringas y otros utensilios, y tienen frecuentemente prácticas de sexo no seguro. Respecto a la comorbilidad asociada, se destacan los trastornos alimentarios, el insomnio, las alteraciones cardiovasculares y autónomo-vegetativas, entre los que se aparecen la sudoración y las variaciones en la temperatura corporal. También se encontró la presencia de sobredosis, las ideas recurrentes de suicidio y, en menor medida, las enfermedades infectocontagiosasIntroduction: This article evaluates the physical and mental co morbidity associated to drug consumption in a group of 42 heroin consumers in the city of Medellin, Colombia, who were contacted through treatment centers using the snowball technique. Method: Data regarding the socio-demographic profile, consumption practices, rituals, paraphernalia exchange, sexual behaviors and protection, suicidal ideas or attempts, family and personal background, illnesses and physical and

  10. Injuria pulmonar aguda asociada a transfusión en el embarazo: Reporte de un caso y revisión de la literatura Transfusion-related acute lung injury during pregnancy: A case report and literature review

    Directory of Open Access Journals (Sweden)

    Teófilo Jara-Mori

    2008-03-01

    Full Text Available La injuria pulmonar aguda asociada a transfusión (TRALI es un evento poco frecuente, especialmente raro en la práctica obstétrica. Sin embargo, hoy en día es la principal causa de muerte asociada a dicho procedimiento. Su mortalidad es alrededor del 6%. Desde el 2004 se definieron los criterios diagnósticos de TRALI que deben ser tenidos en cuenta para su identificación y tratamientos tempranos. Se presenta el caso de una gestante con 30 semanas de embarazo, hospitalizada con diagnóstico de infección urinaria, a quien se le transfundió una unidad de glóbulos rojos después de evaluar un resultado de hemoglobina de 6,7 g/dl, una hora después presentó síndrome de dificultad respiratoria aguda severa que requirió ventilación mecánica por cuatro días. El resultado materno y perinatal fue óptimo con resolución completa del evento respiratorio. Se considera relevante reportar el caso para motivar la notificación de esta complicación, pues se desconoce la influencia del embarazo sobre ella. Además, se le debe informar al banco de sangre para fortalecer el sistema de hemovigilancia.Transfusion-related acute lung injury (TRALI is an uncommon complication, especially in obstetrics. The mortality rate for this event is around 6% and has now become the leading cause of transfusion-related death. TRALI diagnosis criteria have been well established since 2004 and they must be considered for its early identification and treatment. We report a case of a 30-week pregnant woman who suffered a urinary tract infection. She received a blood transfusion with one unit of red blood cells due to having 6.7 gr/dl having 6.7 gr/dl haemoglobin. One hour later she developed an acute respiratory distress syndrome and required four days’ mechanical ventilation. Maternal and neonatal outcome were optimal, leading to complete resolution of respiratory symptoms. This case should be shared to motivate reporting this kind of complication because the

  11. 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

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

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_158661.html Bacteria Experiment May Point Way to Slow Zika's Spread ... 2016 (HealthDay News) -- Experiments in mosquitoes suggest that bacteria may help curb the spread of the Zika ...

  13. Smoking Triggers Big Changes in Mouth Bacteria, Study Finds

    Science.gov (United States)

    ... 158024.html Smoking Triggers Big Changes in Mouth Bacteria, Study Finds But quitting eventually returns levels to ... research also found that the proper mix of bacteria in the mouth is restored if people quit ...

  14. Environmental pollution detection and bioremediation by marine bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.; De, J.; Iyer, S.R.

    Microorganisms, in particular bacteria, play far more important ecological roles in natural environments than their small sizes would suggest. The environment for bacteria is everything that surrounds and sustains them including air, plant, animal...

  15. 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 ...

  16. 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 ...

  17. Molecular and chemical dialogues in bacteria-protozoa interactions

    NARCIS (Netherlands)

    Song, Chunxu; Mazzola, M.; Cheng, Xu; Oetjen, Janina; Alexandrov, Theodore; Dorrestein, Pieter C.; Watrous, Jeramie; van der Voort, Menno; Raaijmakers, Jos

    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

  18. 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 ...

  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. 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.

  1. 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 ...

  2. 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...

  3. 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 ...

  4. New Insight on the Response of Bacteria to Fluoride

    OpenAIRE

    Breaker, R R

    2012-01-01

    Fluoride has been used for decades to prevent caries and it is well established that this anion can inhibit the growth of bacteria. However, the precise effects that fluoride has on bacteria and the mechanisms that bacteria use to overcome fluoride toxicity have largely remained unexplored. Recently, my laboratory reported the discovery of biological systems that bacteria use to sense fluoride and reduce fluoride toxicity. These sensors and their associated genes are very widespread in biolog...

  5. 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...

  6. Probiotic bacteria in prevention and treatment of diarrhea

    OpenAIRE

    Jasmina Havranek; Šimun Zamberlin; Iva Dolenčić Špehar; Tamara Prtilo; Milna Tudor; Dubravka Samaržija

    2009-01-01

    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 preventi...

  7. [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

  8. Ancient bacteria show evidence of DNA repair

    DEFF Research Database (Denmark)

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

    2007-01-01

    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...... 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.......-term survival of bacteria sealed in frozen conditions for up to one million years. Our results show evidence of bacterial survival in samples up to half a million years in age, making this the oldest independently authenticated DNA to date obtained from viable cells. Additionally, we find strong evidence that...

  9. 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.

  10. Horizontal gene transfer between bacteria and animals.

    Science.gov (United States)

    Dunning Hotopp, Julie C

    2011-04-01

    Horizontal gene transfer is increasingly described between bacteria and animals. Such transfers that are vertically inherited have the potential to influence the evolution of animals. One classic example is the transfer of DNA from mitochondria and chloroplasts to the nucleus after the acquisition of these organelles by eukaryotes. Even today, many of the described instances of bacteria-to-animal transfer occur as part of intimate relationships such as those of endosymbionts and their invertebrate hosts, particularly insects and nematodes, while numerous transfers are also found in asexual animals. Both of these observations are consistent with modern evolutionary theory, in particular the serial endosymbiotic theory and Muller's ratchet. Although it is tempting to suggest that these particular lifestyles promote horizontal gene transfer, it is difficult to ascertain given the nonrandom sampling of animal genome sequencing projects and the lack of a systematic analysis of animal genomes for such transfers. PMID:21334091

  11. 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

  12. 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)

  13. The Chemical Ecology of Predatory Soil Bacteria.

    Science.gov (United States)

    Findlay, Brandon L

    2016-06-17

    The study of natural products is entering a renaissance, driven by the discovery that the majority of bacterial secondary metabolites are not produced under standard laboratory conditions. Understanding the ecological role of natural products is key to efficiently directing our screening efforts, and to ensuring that each screen efficiently captures the full biosynthetic repertoire of the producing organisms. Myxobacteria represent one of the most common and diverse groups of bacteria, with roughly 2500 strains publically available. Fed largely through predation, the myxobacteria have developed a large repertoire of natural products that target other microorganisms, including bacteria and fungi. Many of these interactions can be observed in predation assays, providing direct evidence for environmental interactions. With a focus on Myxococcus xanthus, this review will highlight how recent advances in myxobacteria are revealing the chemical ecology of bacterial natural products. PMID:27035738

  14. Emerging roles of RNA modifications in bacteria.

    Science.gov (United States)

    Marbaniang, Carmelita Nora; Vogel, Jörg

    2016-04-01

    RNA modifications are known to abound in stable tRNA and rRNA, where they cluster around functionally important regions. However, RNA-seq based techniques profiling entire transcriptomes are now uncovering an abundance of modified ribonucleotides in mRNAs and noncoding RNAs, too. While most of the recent progress in understanding the regulatory influence of these new RNA modifications stems from eukaryotes, there is growing evidence in bacteria for modified nucleotides beyond the stable RNA species, including modifications of small regulatory RNAs. Given their small genome size, good genetic tractability, and ample knowledge of modification enzymes, bacteria offer excellent model systems to decipher cellular functions of RNA modifications in many diverse physiological contexts. This review highlights how new global approaches combining classic analysis with new sequencing techniques may usher in an era of bacterial epitranscriptomics. PMID:26803287

  15. 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. PMID:25701621

  16. 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...

  17. Food preservation using antifungal lactic acid bacteria

    OpenAIRE

    Crowley, Sarah Catherine Mary

    2013-01-01

    Fungal spoilage of food and feed prevails as a major problem for the food industry. The use antifungal-producing lactic acid bacteria (LAB) may represent a safer, natural alternative to the use of chemical preservatives in foods. A large scale screen was undertaken to identify a variety of LAB with antifungal properties from plant, animal and human sources. A total of 6,720 LAB colonies were isolated and screened for antifungal activity against the indicator Penicillium expansum. 94 broad-spe...

  18. RNA-Seq for Plant Pathogenic Bacteria

    OpenAIRE

    Kimbrel, Jeffrey A.; Yanming Di; Cumbie, Jason S.; Chang, Jeff H.

    2011-01-01

    The throughput and single-base resolution of RNA-Sequencing (RNA-Seq) have contributed to a dramatic change in transcriptomic-based inquiries and resulted in many new insights into the complexities of bacterial transcriptomes. RNA-Seq could contribute to similar advances in our understanding of plant pathogenic bacteria but it is still a technology under development with limitations and unknowns that need to be considered. Here, we review some new developments for RNA-Seq and highlight recent...

  19. 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...

  20. 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.

  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. Separation and Purification of Bacteria from Soil

    OpenAIRE

    Bakken, Lars R.

    1985-01-01

    Bacteria were released and separated from soil by a simple blending-centrifugation procedure. The percent yield of bacterial cells (microscopic counts) in the supernatants varied over a wide range depending on the soil type. The superantants contained large amounts of noncellular organic material and clay particles. Further purification of the bacterial cells was obtained by centrifugation in density gradients, whereby the clay particles and part of the organic materials sedimented. A large p...

  3. Revolutionizing membrane protein overexpression in bacteria

    OpenAIRE

    Schlegel, Susan; Klepsch, Mirjam; Gialama, Dimitra; Wickström, David; Slotboom, Dirk Jan; De Gier, Jan‐Willem

    2010-01-01

    Summary The bacterium Escherichia coli is the most widely used expression host for overexpression trials of membrane proteins. Usually, different strains, culture conditions and expression regimes are screened for to identify the optimal overexpression strategy. However, yields are often not satisfactory, especially for eukaryotic membrane proteins. This has initiated a revolution of membrane protein overexpression in bacteria. Recent studies have shown that it is feasible to (i) engineer or ...

  4. 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...

  5. Electromagnetic low-frequency fields and bacteria

    Czech Academy of Sciences Publication Activity Database

    Foltýn, D.; Čermáková, E.; Kolářová, M.; Bartušek, Karel

    Košice : RVS VLA Košice, 2002 - (Džunda, M.; Brůnová, B.), s. 133 - 137 ISBN 80-7166-034-5. [New trends of development in aviation. Košice (SK), 01.09.2002] Institutional research plan: CEZ:AV0Z2065902 Keywords : low-frequency fields * bacteria Staphylococcus aureus * low-frequency ELM fields Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  6. Biology of Moderately Halophilic Aerobic Bacteria

    OpenAIRE

    Nieto Gutiérrez, Joaquín José; Ventosa Ucero, Antonio; Oren, Aharon

    1998-01-01

    The moderately halophilic heterotrophic aerobic bacteria form a diverse group of microorganisms. The property of halophilism is widespread within the bacterial domain. Bacterial halophiles are abundant in environments such as salt lakes, saline soils, and salted food products. Most species keep their intracellular ionic concentrations at low levels while synthesizing or accumulating organic solutes to provide osmotic equilibrium of the cytoplasm with the surrounding medium. Complex mechanisms...

  7. 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...

  8. Ferric Iron Reduction by Acidophilic Heterotrophic Bacteria

    OpenAIRE

    Johnson, D. Barrie; McGinness, Stephen

    1991-01-01

    Fifty mesophilic and five moderately thermophilic strains of acidophilic heterotrophic bacteria were tested for the ability to reduce ferric iron in liquid and solid media under aerobic conditions; about 40% of the mesophiles (but none of the moderate thermophiles) displayed at least some capacity to reduce iron. Both rates and extents of ferric iron reduction were highly strain dependent. No acidophilic heterotroph reduced nitrate or sulfate, and (limited) reduction of manganese(IV) was note...

  9. 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.

  10. Quorum Sensing in Gram-Negative Bacteria

    OpenAIRE

    BOŞGELMEZ-TINAZ, Gülgün

    2003-01-01

    It has become increasingly and widely recognised that bacteria do not live as isolated entities but instead exist as communities that exploit elaborate systems of intercellular communication to facilitate their adaptation to changing environmental conditions. A well-characterised example of such intercellular communication is quorum sensing. Quorum sensing depends on the production of diffusible signal molecules termed autoinducers or pheromones, which enable a bacterium to monitor its own ce...

  11. 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...

  12. Evolution of transcriptional regulatory circuits in bacteria

    OpenAIRE

    Perez, J. Christian; Groisman, Eduardo A.

    2009-01-01

    Related organisms typically respond to a given cue by altering the level or activity of orthologous transcription factors, which, paradoxically, often regulate expression of distinct gene sets. Although promoter rewiring of shared genes is primarily responsible for regulatory differences among related eukaryotic species, in bacteria, species-specific genes are often controlled by ancestral transcription factors and regulatory circuit evolution has been further shaped by horizontal gene transf...

  13. Mutation, Selection and Genetic Interactions in Bacteria

    OpenAIRE

    Gordo, I.; Sousa, A.

    2010-01-01

    Mutation is the ultimate source of genetic variation. The rate at whichnew mutations typically occurs, their effects on fitness and the strength and type of genetic interactions between different mutations are key for understanding the evolution of any population. Estimates of these parameters in organisms such as bacteria will have a profound impact on our understanding of their biology, diversity, rate of speciation and in our health. Experimental evolution with bact...

  14. Experimental evolution with bacteria in complex environments

    OpenAIRE

    Hall, Alex R.

    2009-01-01

    Experiments with microbes are a powerful tool for addressing general questions in evolutionary ecology. Microbial evolution is also interesting in its own right, and often clinically relevant. I have used experimental evolution of bacteria (Pseudomonas spp.) in controlled laboratory environments to investigate the role of environmental heterogeneity in the evolution of phenotypic diversity. Some of my results provide insight on general processes, while others are specific to ba...

  15. Cold atmospheric plasma decontamination against nosocomial bacteria

    OpenAIRE

    Klämpfl , Tobias Gabriel

    2014-01-01

    Nosocomial pathogens are a considerable public threat. In order to limit their spread, cold atmospheric plasma (CAP) was investigated as new alternative to common decontamination strategies. During my work I developed a Surface micro-discharge (SMD) electrode system, characterized the CAP generated at ambient air conditions, studied its decontaminating behavior against nosocomial bacteria such as Clostridium difficile endospores and revealed factors influencing the decontamination. All in all...

  16. [Phylogenetic analysis of bacteria of extreme ecosystems].

    Science.gov (United States)

    Romanovskaia, V A; Parfenova, V V; Bel'kova, N L; Sukhanova, E V; Gladka, G V; Tashireva, A A

    2014-01-01

    Phylogenetic analysis of aerobic chemoorganotrophic bacteria of the two extreme regions (Dead Sea and West Antarctic) was performed on the basis of the nucleotide sequences of the 16S rRNA gene. Thermotolerant and halotolerant spore-forming bacteria 7t1 and 7t3 of terrestrial ecosystems Dead Sea identified as Bacillus licheniformis and B. subtilis subsp. subtilis, respectively. Taking into account remote location of thermotolerant strain 6t1 from closely related strains in the cluster Staphylococcus, 6t1 strain can be regarded as Staphylococcus sp. In terrestrial ecosystems, Galindez Island (Antarctic) detected taxonomically diverse psychrotolerant bacteria. From ornithogenic soil were isolated Micrococcus luteus O-1 and Microbacterium trichothecenolyticum O-3. Strains 4r5, 5r5 and 40r5, isolated from grass and lichens, can be referred to the genus Frondihabitans. These strains are taxonomically and ecologically isolated and on the tree diagram form the joint cluster with three isolates Frondihabitans sp., isolated from the lichen Austrian Alps, and psychrotolerant associated with plants F. cladoniiphilus CafT13(T). Isolates from black lichen in the different stationary observation points on the south side of a vertical cliff identified as: Rhodococcus fascians 181n3, Sporosarcina aquimarina O-7, Staphylococcus sp. 0-10. From orange biofilm of fouling on top of the vertical cliff isolated Arthrobacter sp. 28r5g1, from the moss-- Serratia sp. 6r1g. According to the results, Frondihabitans strains most frequently encountered among chemoorganotrophic aerobic bacteria in the Antarctic phytocenoses. PMID:25007437

  17. 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...

  18. 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

  19. Calculations of magnetic susceptibility of magnetoactic bacteria culture

    Czech Academy of Sciences Publication Activity Database

    Zablotskyy, Vitaliy A.; Yurchenko, Vitaliy; Kamysa, Y.; Chelombetskaya, M.

    2001-01-01

    Roč. 234, - (2001), s. 575-583. ISSN 0304-8853 Institutional research plan: CEZ:AV0Z1010914 Keywords : magnetotactic bacteria * magnetic susceptibility of magnetotactic bacteria * magnetic moment of magnetotactic bacteria Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.329, year: 2001

  20. 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

  1. TMDLs (Total Maximum Daily Loads) for Bacteria Impairments

    OpenAIRE

    Benham, Brian Leslie, 1960-; Zeckoski, Sara C.

    2009-01-01

    When the concentration of bacteria exceeds the state-specified water-quality criteria, the water is deemed to have a bacteria or pathogen impairment. This publication explains how bacteria impairments are determined and how this relates to the TMDL process.

  2. 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.

  3. 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.

  4. 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 to the...

  5. Diversity and ecology of oxalotrophic bacteria.

    Science.gov (United States)

    Hervé, Vincent; Junier, Thomas; Bindschedler, Saskia; Verrecchia, Eric; Junier, Pilar

    2016-02-01

    Oxalate is present in environments as diverse as soils or gastrointestinal tracts. This organic acid can be found as free acid or forming metal salts (e.g. calcium, magnesium). Oxalotrophy, the ability to use oxalate as carbon and energy sources, is mainly the result of bacterial catabolism, which can be either aerobic or anaerobic. Although some oxalotrophic bacterial strains are commonly used as probiotics, little is known about the diversity and ecology of this functional group. This review aims at exploring the taxonomic distribution and the phylogenetic diversity of oxalotrophic bacteria across biomes. In silico analyses were conducted using the two key enzymes involved in oxalotrophy: formyl-coenzyme A (CoA) transferase (EC 2.8.3.16) and oxalyl-CoA decarboxylase (EC 4.1.1.8), encoded by the frc and oxc genes, respectively. Our analyses revealed that oxalate-degrading bacteria are restricted to three phyla, namely Actinobacteria, Firmicutes and Proteobacteria and originated from terrestrial, aquatic and clinical environments. Diversity analyses at the protein level suggest that total Oxc diversity is more constrained than Frc diversity and that bacterial oxalotrophic diversity is not yet fully described. Finally, the contribution of oxalotrophic bacteria to ecosystem functioning as well as to the carbon cycle is discussed. PMID:26748805

  6. Bacteria-powered battery on paper.

    Science.gov (United States)

    Fraiwan, Arwa; Choi, Seokheun

    2014-12-21

    Paper-based devices have recently emerged as simple and low-cost paradigms for fluid manipulation and analytical/clinical testing. However, there are significant challenges in developing paper-based devices at the system level, which contain integrated paper-based power sources. Here, we report a microfabricated paper-based bacteria-powered battery that is capable of generating power from microbial metabolism. The battery on paper showed a very short start-up time relative to conventional microbial fuel cells (MFCs); paper substrates eliminated the time traditional MFCs required to accumulate and acclimate bacteria on the anode. Only four batteries connected in series provided desired values of current and potential to power an LED for more than 30 minutes. The battery featured (i) a low-cost paper-based proton exchange membrane directly patterned on commercially available parchment paper and (ii) paper reservoirs for holding the anolyte and the catholyte for an extended period of time. Based on this concept, we also demonstrate the use of paper-based test platforms for the rapid characterization of electricity-generating bacteria. This paper-based microbial screening tool does not require external pumps/tubings and represents the most rapid test platform (<50 min) compared with the time needed by using traditional screening tools (up to 103 days) and even recently proposed MEMS arrays (< 2 days). PMID:25363848

  7. 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.

  8. 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%.

  9. Distribution of coliform bacteria in waste water

    Directory of Open Access Journals (Sweden)

    Dau Lal Bohra

    2012-02-01

    Full Text Available Biological activity of water can be apparently judged by the colonization of bacteria (microbes. In order to find out the extent of pollution and the relationship between inorganic matters and microbiota, a quantitative and qualitative analysis of bacteria in various types of sewage waters, namely sewage water by the residential colonies (group I, industrial waste water (group II, sewage treatment hub (group III, unorganized collected waste water (group IV and old residential waste collection center (group V, of Bikaner city (Rajasthan, India was carried out from February, 2010 to May, 2010. Water samples were taken from surface only owing to low depth and investigated for various abiotic factors (viz. transparency, pH, carbonate, bicarbonate, total alkalinity, total hardness, salinity, chloride, calcium, magnesium, sulphate, nitrate, silica, and inorganic phosphorous and biotic factors (viz. number and diversity of bacteria. The domestic sewage water causes major water borne diseases basing upon Total Bacterial Count (TBC and coliform Count (CC. The coliform count in the present study ranged from 2.5 to 5.12 MPN/mL. Comparision of microbial population in sewage water from all different Groups was done and the higher values of TBC and CC were recorded only in Sewage treatement hub (Group III.

  10. Bacteria associated with Amblyomma cajennense tick eggs.

    Science.gov (United States)

    Machado-Ferreira, Erik; Vizzoni, Vinicius Figueiredo; Piesman, Joseph; Gazeta, Gilberto Salles; Soares, Carlos Augusto Gomes

    2015-12-01

    Ticks represent a large group of pathogen vectors that blood feed on a diversity of hosts. In the Americas, the Ixodidae ticks Amblyomma cajennense are responsible for severe impact on livestock and public health. In the present work, we present the isolation and molecular identification of a group of culturable bacteria associated with A. cajennense eggs from females sampled in distinct geographical sites in southeastern Brazil. Additional comparative analysis of the culturable bacteria from Anocentor nitens, Rhipicephalus sanguineus and Ixodes scapularis tick eggs were also performed. 16S rRNA gene sequence analyses identified 17 different bacterial types identified as Serratia marcescens, Stenotrophomonas maltophilia, Pseudomonas fluorescens, Enterobacter spp., Micrococcus luteus, Ochrobactrum anthropi, Bacillus cereus and Staphylococcus spp., distributed in 12 phylogroups. Staphylococcus spp., especially S. sciuri, was the most prevalent bacteria associated with A. cajennense eggs, occurring in 65% of the samples and also frequently observed infecting A. nitens eggs. S. maltophilia, S. marcescens and B. cereus occurred infecting eggs derived from specific sampling sites, but in all cases rising almost as pure cultures from infected A. cajennense eggs. The potential role of these bacterial associations is discussed and they possibly represent new targets for biological control strategies of ticks and tick borne diseases. PMID:26537602

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. Clinical Practice Guidelines for Ventilation Associated Pneumonia. Guía de práctica clínica para el tratamiento de la neumonía asociada al ventilador.

    Directory of Open Access Journals (Sweden)

    Eddy Pereira Valdés.

    2009-03-01

    Full Text Available Clinical Practice Guidelines for Ventilation Associated Pneumonia. Conceptualized as the bacterial pneumonia that develops in patients receiving mechanical ventilation for more than 48 hours, which is not present at the beginning of the ventilation. We review the concept, prevention and treatment. It includes assessment guidelines focused on the most important aspects to be accomplished.Guía de práctica clínica para el tratamiento de la neumonía asociada al ventilador. Conceptualizada como la neumonía bacteriana que se desarrolla en pacientes que reciben ventilación mecánica por más de 48 horas y que no está presente en el momento de la intubación. Se revisan el concepto, la prevención y su tratamiento. Concluye con su guía de evaluación, enfocada en los aspectos más importantes a cumplir.

  16. 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.

  17. 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.

  18. 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

  19. 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

  20. Bacteria-Mineral Interactions on the Surfaces of Metal-Resistant Bacteria

    International Nuclear Information System (INIS)

    The extraordinary ability of indigenous microorganisms, like metal-resistant bacteria, for biotransformation of toxic compounds is of considerable interest for the emerging area of environmental bioremediation. However, the underlying mechanisms by which metal-resistant bacteria transform toxic compounds are currently unknown and await elucidation. The project's objective was to study stress-induced responses of metal-resistant bacteria to environmental changes and chemical stimulants. This project involved a multi-institutional collaboration of our LLNL group with the group of Dr. H.-Y. Holman (Lawrence Berkeley National Laboratory). In this project, we have utilized metal-resistant bacteria Arthrobacter oxydans as a model bacterial system. We have utilized atomic force microscopy (AFM) to visualize for the first time at the nanometer scale formation of stress-induced structures on bacterial surfaces in response to Cr (VI) exposure. We have demonstrated that structure, assembly, and composition of these stress-induced structures are dependent on Cr (VI) concentrations. Our AFM observations of the appearance and development of stress-induced layers on the surfaces of Arthrobacter oxydans bacteria exposed to Cr (VI) were confirmed by Dr. Holman's biochemical, electron microscopy, and synchrotron infrared spectromicroscopy studies. In general, in vitro imaging of live microbial and cellular systems represents one of the most challenging issues in application of AFM. Various approaches for immobilization of bacteria on the substrate for in vitro imaging were tested in this project. Imaging of live bacteria was achieved, however further optimization of experimental methods are needed for high-resolution visualization of the cellular environmental structural dynamics by AFM. This project enhanced the current insight into molecular architecture, structural and environmental variability of bacterial systems. The project partially funded research for two book chapters (1

  1. Assessment of the Levels of Airborne Bacteria, Gram-Negative Bacteria, and Fungi in Hospital Lobbies

    Directory of Open Access Journals (Sweden)

    Dong-Uk Park

    2013-01-01

    Full Text Available Aims: We assessed the levels of airborne bacteria, Gram-negative bacteria (GNB, and fungi in six hospital lobbies, and investigated the environmental and hospital characteristics that affected the airborne microorganism levels. Methods: An Andersen single-stage sampler equipped with appropriate nutrition plate agar was used to collect the samples. The three types of microorganisms were repeatedly collected at a fixed location in each hospital (assumed to be representative of the entire hospital lobby from 08:00 through 24:00, with a sampling time of less than 5 min. Temperature and relative humidity were simultaneously monitored. Results: Multiple regression analysis was used to identify the major factors affecting microorganism levels. The average levels of bacteria (7.2 × 102 CFU/m3, GNB (1.7 × 10 CFU/m3, and fungi (7.7 × 10 CFU/m3 indicated that all hospital lobbies were generally contaminated. Season was the only factor that significantly affected the levels of all microorganisms (p < 0.0001, where contamination was the highest during the summer, significantly higher than during the winter. Other significant factors varied by microorganism, as follows: airborne bacteria (number of people in the lobby, sampling time, GNB (scale of hospital, and fungi (humidity and air temperature. Conclusions: Hospital lobby air was generally contaminated with microorganisms, including bacteria, GNB, and fungi. Environmental factors that may significantly influence the airborne concentrations of these agents should be managed to minimize airborne levels.

  2. Isolation of radiation-resistant bacteria without exposure to irradiation

    International Nuclear Information System (INIS)

    Resistance to desiccation was utilized in the selection of highly radiation-resistant asporogenous bacteria from nonirradiated sources. A bacterial suspension in phosphate buffer was dried in a thin film at 250C and 33% relative humidity. Storage under these conditions for 15 days or more reduced the number of radiation-sensitive bacteria. Further selection for radiation-resistant bacteria was obtained by irradiation of bacteria on velveteen in the replication process, therby avoiding the toxic effect of irradiated media. The similarity of radiation resistance and identifying characteristics in irradiated and non-irradiated isolates should allay some concerns that highly radiation-resistance bacteria have been permanently altered by radiation selection

  3. 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.

  4. Hessian fly-associated bacteria: transmission, essentiality, and composition.

    Directory of Open Access Journals (Sweden)

    Raman Bansal

    Full Text Available Plant-feeding insects have been recently found to use microbes to manipulate host plant physiology and morphology. Gall midges are one of the largest groups of insects that manipulate host plants extensively. Hessian fly (HF, Mayetiola destructor is an important pest of wheat and a model system for studying gall midges. To examine the role of bacteria in parasitism, a systematic analysis of bacteria associated with HF was performed for the first time. Diverse bacteria were found in different developmental HF stages. Fluorescent in situ hybridization detected a bacteriocyte-like structure in developing eggs. Bacterial DNA was also detected in eggs by PCR using primers targeted to different bacterial groups. These results indicated that HF hosted different types of bacteria that were maternally transmitted to the next generation. Eliminating bacteria from the insect with antibiotics resulted in high mortality of HF larvae, indicating that symbiotic bacteria are essential for the insect to survive on wheat seedlings. A preliminary survey identified various types of bacteria associated with different HF stages, including the genera Enterobacter, Pantoea, Stenotrophomonas, Pseudomonas, Bacillus, Ochrobactrum, Acinetobacter, Alcaligenes, Nitrosomonas, Arcanobacterium, Microbacterium, Paenibacillus, and Klebsiella. Similar bacteria were also found specifically in HF-infested susceptible wheat, suggesting that HF larvae had either transmitted bacteria into plant tissue or brought secondary infection of bacteria to the wheat host. The bacteria associated with wheat seedlings may play an essential role in the wheat-HF interaction.

  5. 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.

  6. 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.

  7. Bacteria-bacteria interactions within the microbiota of the ancestral metazoan Hydra contribute to fungal resistance.

    Science.gov (United States)

    Fraune, Sebastian; Anton-Erxleben, Friederike; Augustin, René; Franzenburg, Sören; Knop, Mirjam; Schröder, Katja; Willoweit-Ohl, Doris; Bosch, Thomas C G

    2015-07-01

    Epithelial surfaces of most animals are colonized by diverse microbial communities. Although it is generally agreed that commensal bacteria can serve beneficial functions, the processes involved are poorly understood. Here we report that in the basal metazoan Hydra, ectodermal epithelial cells are covered with a multilayered glycocalyx that provides a habitat for a distinctive microbial community. Removing this epithelial microbiota results in lethal infection by the filamentous fungus Fusarium sp. Restoring the complex microbiota in gnotobiotic polyps prevents pathogen infection. Although mono-associations with distinct members of the microbiota fail to provide full protection, additive and synergistic interactions of commensal bacteria are contributing to full fungal resistance. Our results highlight the importance of resident microbiota diversity as a protective factor against pathogen infections. Besides revealing insights into the in vivo function of commensal microbes in Hydra, our findings indicate that interactions among commensal bacteria are essential to inhibit pathogen infection. PMID:25514534

  8. 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.

  9. 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

  10. Are Bacteria more dangerous in space?

    International Nuclear Information System (INIS)

    With a mission to Mars and a permanent base on the moon as the ultimate dream, space travel is continually pushing back the frontiers. But long space missions present great challenges for science, for example in the field of microbiology. Together with the European Space Agency (ESA), SCK-CEN is studying the effects of space travel conditions on the behaviour of bacteria. In 2009 the SCK-CEN experts completed four innovative research projects at the cutting edge of microbiology, radiation sciences and space travel.

  11. The Origin And Spread Of Airborne Bacteria

    Science.gov (United States)

    Henderson-Begg, S. K.; Moffett, B. F.

    2009-12-01

    The presence of bacteria in clouds may affect their radiation and precipitation properties as some species are able to catalyse the freezing of water at high temperatures (-2C to -10C). Where cloud-borne bacteria originate and the distances they are able to travel in the air remains a mystery. In this study we have attempted to address these issues by comparing metagenomic DNA sequences from air samples with those from other environmental sources. Air samples were collected on 1 July 2009 from a hill top at Thursley Nature Reserve in Surrey, United Kingdom, a rural site, 31 miles from the nearest stretch of coastline, and on 6 July 2009 from the top of a six storey building in Stratford on the East end of London, 38 miles from the nearest coastal area. Samples were collected using the Karcher DS5500 vacuum into a liquid filled collection vessel at an air flow rate of 3.3 m3 min-1 over a 4 hour period. Samples were then concentrated and the bacterial content was investigated by PCR, cloning and sequencing of 16S rRNA genes. During the collection period on 1 July the Royston Weather Station in the South East of England recorded wind speed of 1.9 miles/hour in an Easterly direction, with no cloud cover, relative humidity of 74% and atmospheric pressure of 1021.6 mB. On 6 July wind speed was 9.8 miles/hour in a South Westerly direction, there was light cloud cover, relative humidity was 73.8% and atmospheric pressure was 1002.8 mB. Twenty cloned 16S PCR products from each air sample were sequenced. The species identification of each clone is shown in Table 1. The diversity of bacteria found at both sites was similar, with Stenotrophomona and Pedobacteria species dominating both samples. When the DNA sequences were blasted against the environmental samples database, all sequences were found to display greatest homology to metagenomic DNA from marine sources. This may suggest that the most numerous bacteria in air samples originate in the oceans. Taking account of the

  12. Bacteriophage Infection of Model Metal Reducing Bacteria

    Science.gov (United States)

    Weber, K. A.; Bender, K. S.; Gandhi, K.; Coates, J. D.

    2008-12-01

    Microbially-mediated metal reduction plays a significant role controlling contaminant mobility in aqueous, soil, and sedimentary environments. From among environmentally relevant microorganisms mediating metal reduction, Geobacter spp. have been identified as predominant metal-reducing bacteria under acetate- oxidizing conditions. Due to the significance of these bacteria in environmental systems, it is necessary to understand factors influencing their metabolic physiology. Examination of the annotated finished genome sequence of G. sulfurreducens PCA, G. uraniumreducens Rf4, G. metallireduceans GS-15 as well as a draft genome sequence of Geobacter sp. FRC-32 have identified gene sequences of putative bacteriophage origin. Presence of these sequences indicates that these bacteria are susceptible to phage infection. Polymerase chain reaction (PCR) primer sets designed tested for the presence of 12 of 25 annotated phage-like sequences in G. sulfurreducens PCA and 9 of 17 phage-like sequences in FRC- 32. The following genes were successfully amplified in G. sulfurreducens PCA: prophage type transcription regulator, phage-induced endonuclease, phage tail sheath, 2 phage tail proteins, phage protein D, phage base plate protein, phage-related DNA polymerase, integrase, phage transcriptional regulator, and Cro-like transcription regulator. Nine of the following sequences were present in FRC-32: 4 separate phage- related proteins, phage-related tail component, viron core protein, phage Mu protein, phage base plate, and phage tail sheath. In addition to the bioinformatics evidence, incubation of G. sulfurreducens PCA with 1 μg mL-1 mytomycin C (mutagen stimulating prophage induction) during mid-log phase resulted in significant cell lysis relative to cultures that remained unamended. Cell lysis was concurrent with an increase in viral like particles enumerated using epifluorescent microscopy. In addition, samples collected following this lytic event (~44hours) were

  13. 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...

  14. Electroactive biofilms of sulphate reducing bacteria

    International Nuclear Information System (INIS)

    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-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

  15. 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

  16. Application of Pulsed Electric Field on Bacteria

    Czech Academy of Sciences Publication Activity Database

    Kadlec, Tomáš; Babický, Václav; Člupek, Martin; Vrbová, M.

    Prague: Czech Technical University in Prague, 2011 - (Pospíšilová, M.; Vrbová, M.; Macháň, R.), s. 161-164 ISBN 978-80-01-04915-0. [Instruments and Methods for Biology and Medicine 2011. Kladno (CZ), 02.06.2011-02.06.2011] R&D Projects: GA AV ČR IAAX00430802; GA ČR(CZ) GD104/09/H080 Institutional research plan: CEZ:AV0Z20430508 Keywords : Pulsed Electric Field * Bacteria Subject RIV: BO - Biophysics

  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. 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

  19. The effect of lactic acid bacteria on cocoa bean fermentation.

    Science.gov (United States)

    Ho, Van Thi Thuy; Zhao, Jian; Fleet, Graham

    2015-07-16

    Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of cocoa pulp by microorganisms is crucial for developing chocolate flavor precursors. Yeasts conduct an alcoholic fermentation within the bean pulp that is essential for the production of good quality beans, giving typical chocolate characters. However, the roles of bacteria such as lactic acid bacteria and acetic acid bacteria in contributing to the quality of cocoa bean and chocolate are not fully understood. Using controlled laboratory fermentations, this study investigated the contribution of lactic acid bacteria to cocoa bean fermentation. Cocoa beans were fermented under conditions where the growth of lactic acid bacteria was restricted by the use of nisin and lysozyme. The resultant microbial ecology, chemistry and chocolate quality of beans from these fermentations were compared with those of indigenous (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae, the lactic acid bacteria Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in control fermentations. In fermentations with the presence of nisin and lysozyme, the same species of yeasts and acetic acid bacteria grew but the growth of lactic acid bacteria was prevented or restricted. These beans underwent characteristic alcoholic fermentation where the utilization of sugars and the production of ethanol, organic acids and volatile compounds in the bean pulp and nibs were similar for beans fermented in the presence of lactic acid bacteria. Lactic acid was produced during both fermentations but more so when lactic acid bacteria grew. Beans fermented in the presence or absence of lactic acid bacteria were fully fermented, had similar shell weights and gave acceptable chocolates with no differences

  20. 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.