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Sample records for bacilos gram negativos

  1. Bacteremias por bacilos gram-negativos

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    Adrelírio J. R. Gonçalves

    1969-01-01

    Full Text Available São apresentados 31 casos de bacteremia por gram-negativos, assunto que vem merecendo muita atenção dos pesquisadores nos últimos anos. Os organismos etiológicos mais importantes que apareceram em igualdade de freqüência foram Escherichia coli e Klebsiella-Aerobacter, sendo responsáveis por 58% do total das infecções, seguidos por Pseudomonas. A porta de entrada mais freqüente foi o trato urinário em 61,3% dos casos. A infecção foi mais comum no sexo masculino e a faixa etária de 50 a 60 anos predominou. O uso prévio de antibióticos foi um fator predisponente muito importante, seguido pelo uso de esteróides e citostáticos. As principais doenças predisponentes foram diabetes mellitus e neoplasias malignas. Os principais fatores precipitantes foram a manipulação do aparelho urinário, com infecção prévia ou desencadeada, cirurgia do aparelho digestivo, uronatia obstrutiva e obstrução biliar. As principais manifestações clínicas foram a presença de febre, calafrios e hipotensão arterial. A complicação mais freqüente foi o choque bacteriano que incidiu em 58% dos casos, aproximadamente três vêzes aquela relatada na literatura. As outras foram a insuficiência renal aguda, superinfecção e infecção pulmonar metastática. Considerações terapêuticas gerais e esquemas de antibióticos são propostos para estes casos. A mortalidade da bacteremia simples foi de 30,7% e quando associada ao choque elevou-se para 72,2% . As infecções por Pseudomonas foram 100% fatais.

  2. Evolución de la resistencia antimicrobiana de bacilos Gram negativos en unidades de cuidados intensivos en Colombia

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    Cristhian Hernández-Gómez

    2014-04-01

    Full Text Available Introducción. La evolución de la resistencia bacteriana constituye una amenaza para la salud pública mundial. Los sistemas de vigilancia epidemiológica han integrado técnicas de biología molecular para mejorar las estrategias de control. Objetivo. Describir los perfiles moleculares y fenotípicos de los bacilos Gram negativos en unidades de cuidados intensivos de 23 hospitales de Colombia entre 2009 y 2012. Materiales y métodos. Se diseñó un estudio descriptivo en 23 hospitales del Grupo para el Estudio de la Resistencia Nosocomial (sic. en Colombia. Se analizaron 38.048 aislamientos usando WHONET durante el periodo descrito. Se describieron perfiles de resistencia para Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa y Acinetobacter baumannii. En 1.248 cepas se realizó reacción en cadena de la polimerasa (PCR para detectar las carbapenemasas clínicamente más relevantes. Resultados. Escherichia coli fue el microorganismo más frecuente (promedio=14,8 %; la frecuencia de aislamientos de K. pneumoniae aumentó de 11 % en 2009 a 15 % en 2012 (p<0,001. La tendencia de los perfiles de multirresistencia aumentó en todas las especies estudiadas. De los aislamientos de K. pneumoniae evaluados, 68,4 % fue positivo para KPC (Klebsiella pneumoniae Carbapenemase, mientras que la VIM (Verona Integron-encoded Metallo-betalactamase en P. aeruginosa se observó en 46,5 %. Conclusiones. Se observó un incremento en la tendencia de los microorganismos hacia la multirresistencia y una amplia distribución de las carbapenemasas. La articulación de la biología molecular con los sistemas de vigilancia permitió integrar el análisis del fenotipo con los mecanismos de resistencia involucrados en las bacterias estudiadas. Este análisis permitirá la elaboración de guías para el uso adecuado de antimicrobianos y contribuirá a la contención de estas bacterias multirresistentes en Colombia.

  3. Resistencia a antibióticos de bacilos GRAM negativos aislados en unidades de cuidados intensivos: Análisis comparativo de dos periódos (1998-2001 Bacterial resistance to antibiotics in gram negative isolates from intensive care units: Comparative analysis between two periods (1998-2001

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    C. H. Rodriguez

    2003-01-01

    Full Text Available Se comparó la incidencia relativa de las diferentes especies de bacilos gram-negativos y la resistencia a varios antibacterianos, en dos muestras de aislamientos clínicos correspondientes a cinco meses del año 1998 y del mismo período del año 2001, con el objetivo de conocer la evolución de ambos, frecuencia de cada especie como agente etiológico, y resistencia a antimicrobianos. Para ello se analizaron en cada período 100 aislamientos de bacilos gram-negativos obtenidos de muestras clínicas de pacientes internados en salas de cuidados intensivos del Hospital de Clínicas José de San Martín. Se determinó la especie bacteriana y la concentración inhibitoria mínima de cada antibiótico. Acinetobacter spp. fue el microorganismo más aislado en ambos períodos. El porcentaje de aislamientos resistentes a imipenem fue del 60%, mientras que a ciprofloxacina y cefalosporinas de tercera generación fue superior al 80%. En Klebsiella pneumoniae el porcentaje de aislamientos resistentes a cefalosporinas de tercera generación disminuyó del 71.4 al 30% (pThe incidence and drug susceptibility of gram-negative isolates from clinical samples of patients from different intensive care units at the Hospital de Clinicas José de San Martín were analysed. Two hundred isolates during the same five months period, in two different years (1998 and 2001 were obtained and evaluated. Acinetobacter spp., was the most frequently isolated microorganism. Resistance to imipenem was observed in 60% of these isolations while resistance to 3rd generation cephalosporin and ciprofloxacin was observed in more than 80%. Klebsiella pneumoniae was not resistant to imipenem, the resistance to 3rd and 4rth generation cephalosporins decreased from 71.4 to 30% of isolates (p<0.05, while ciprofloxacin resistance increased from 5 to 20% (p<0.05. An increasing resistance to imipenem in Pseudomonas aeruginosa was noted, from 15.4 to 68% (p<0.05%; to ciprofloxacin, from 31.4 to

  4. Infection and colonization by Gram-negative bacilli in neonates hospitalized in High Risk Nursery at Uberlandia Federal University Hospital: etiology, resistant phenotypes and risk factors Infecção e colonização por bacilos Gram-negativos em neonatos internados em Berçário de Alto Risco do Hospital da Universidade Federal de Uberlândia: etiologia, fenótipos de resistência e fatores de risco

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    Renata Cristina Cezário

    2004-09-01

    Full Text Available The aims of this study were to determine endemic and epidemic infection due to Gram-negative bacilli, risk factors associated with colonization and infection by these organisms and the resistance phenotypes (ESBL, AmpC in neonates admitted in a High Risk Nursery. The study was conducted during a 21 month period and included: a prospective study to evaluate the neonates with hospital infection and the use of third-generation cephalosporins; a case-control study to determine the risk factors associated with colonization/infection. Rectal and oropharynx cultures were also performed in four opportunities (September and November 2001, February and August 2002. The isolates for which the resistance of ceftazidime was 2 mg/mL were suspected of producing ESBL or AmpC b-lactamases. The incidence of infection by Gram-negative bacilli was 2.4% (89/3.708 neonates, and sepsis (35.9% and conjunctivitis (31.4% were the most common infections. The endemic infections were more prevalent (73.9% and usually associated with Enterobacteriaceae (95.5%, being these organisms also related to colonization, corresponding mainly to isolates of Enterobacter spp. and Klebsiella spp. Two outbreaks of Pseudomonas aeruginosa (n=10 and Acinetobacter baumannii (n=11 were identified during the survey. Univariate analysis showed that risk factors for Gram-negative bacilli infection considered significant included: the length of stay before infection/colonization, exposure to antimicrobial agents, mechanical ventilation, central venous catheters, parenteral nutrition and surgery. The majority of resistance to ceftazidime among Enterobacteriaceae isolates (80.9% was from ESBL phenotype. Administration of third-generation cephalosporins (ceftriaxone led to the emergence of these multiresistant Gram-negative bacilli in the neonatal unit.Os objetivos deste estudo foram determinar infecções endêmicas e epidêmicas por bacilos Gram-negativos, fatores de risco associados a coloniza

  5. Bacilos gram negativos, contaminantes más prevalentes en lentes de contacto blandos usados

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    Castiblanco, Diana; Rodríguez, Martha Fabiola; Mayorga C., Myriam Teresa

    2007-01-01

    Las bacterias son los contaminantes más frecuentes de los lentes de contacto. Objetivo: identificar el tipo de depósitos microbiológicos en lentes de contacto blando (LCB) usados. Materiales y Métodos: 100 lentes de contacto blandos de usuarios o de prueba  de las ópticas, recolectándose 25 lentes para cada grupo de la FDA (Grupo1, 2, 3 y 4, según el contenido de agua e ionicidad del polímero). Los lentes se almacenaron por 20 días en sus estuches individuales hasta su estudio. A cada lente, ...

  6. Bacilos Gram negativos entéricos y no fermentadores de la glucosa en pacientes con enfermedad periimplante

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    Jessika Consuegra

    2011-04-01

    Conclusiones. Un tercio de los implantes estudiados presentaron organismos sobreinfecciosos. Los implantes con lesiones periimplante presentan una mayor frecuencia de bacterias sobreinfecciosas. K. pneumoniae es la especie sobreinfecciosa más frecuente en los implantes estudiados. Se presentó infección múltiple con dichas bacterias en los implantes afectados. Estos microorganismos pueden afectar la estabilidad de los implantes.

  7. Resistencia antibiótica en bacilos gram negativos, cocáceas gram positivas y anaerobios. implicancias terapéuticas

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    C. Alberto Fica, Dr.

    2014-05-01

    Full Text Available La resistencia antibiótica ha limitado progresivamente nuestras posibilidades terapeúticas y ha aumentado los costos. En este artículo se entrega una visión de los mecanismos más frecuentes en bacterias comunes, tanto comunitarias como nosocomiales y las implicancias terapéuticas que generan en el día a día.

  8. Resistencia a antimicrobianos de bacilos Gram negativos aislados en unidades de cuidado intensivo en hospitales de Colombia, WHONET 2003, 2004 y 2005

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    María Consuelo Miranda

    2006-09-01

    Resultados. Los altos porcentajes de resistencia reportados en especial para A. baumannii, corroboraron la presencia de bacterias multirresistentes en las UCI en las instituciones participantes durante el periodo de estudio. Conclusiones. Es urgente crear una red nacional de vigilancia de la resistencia a antimicrobianos de los patógenos hospitalarios y de esta manera mejorar nuestra habilidad para detectar, supervisar y manejar la resistencia a antimicrobianos en Colombia.

  9. Prevalência de bastonetes Gram-negativos isolados da saliva de trabalhadores da saúde

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    Marinésia Aparecida Prado-Palos

    2011-12-01

    Full Text Available O estudo objetivou determinar a prevalência de bastonetes Gram-negativos (BGN isolados da saliva de trabalhadores de saúde de um hospital universitário em Goiânia-Goiás e caracterizar o perfil dos colonizados. De agosto⁄2005 a julho⁄2006, participaram do estudo 278 trabalhadores de saúde responsáveis pelos cuidados assistenciais aos clientes atendidos na instituição. A taxa de portadores foi de 69,4%, destes 44% foram considerados portadores persistentes e 49,2% multicolonizados. Foram isolados 319 BGN, sendo 208 (65,2% enterobactérias e 111 (34,8% não-fermentadores. As principais espécies identificadas foram: Enterobacter aerogenes (17,9%, Klebsiella pneumoniae (16,3%, Enterobacter agglomerans (8,8%. No grupo dos BGN não-fermentadores, foram isoladas 25 (7,8% Pseudomonas aeruginosa. Elevada prevalência de trabalhadores colonizados por BGN foi observada. Os resultados obtidos neste estudo são de grande relevância, pois BGN assumem fundamental importância na etiologia e patogênese de infecções relacionadas à assistência à saúde de pacientes críticos, submetidos a procedimentos invasivos e com permanência prolongada no ambiente nosocomial.

  10. Bactérias gram-negativas em cardeais (Paroaria coronata e Paroaria dominicana) apreendidos do tráfico de animais silvestres

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    Marcos Paulo Vieira Cunha; Marta Brito Guimarães; Yamê Miniero Davies; Liliane Milanelo; Terezinha Knöbl

    2016-01-01

    Anualmente o tráfico de animais silvestres retira milhões de aves da natureza. Os cardeais (Paroaria coronata) e cardeais-do-nordeste (Paroaria dominicana) estão incluídos entre as espécies de aves mais traficadas. A microbiota cloacal de passeriformes de vida livre é composta principalmente por bacilos e cocos gram-positivos, já os bacilos gram-negativos predominam em aves de cativeiro. Em situações de estresse e baixa de imunidade as bactérias gram-negativas podem causar infecções oportunis...

  11. Evaluación del sistema API Coryne, versión 2.0, para la identificación de bacilos gram-positivos difteroides de importancia clínica Evaluation of API Coryne system, version 2.0, for diphteroid gram-positive rods identification with clinical relevance

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    M. N. Almuzara

    2006-12-01

    Full Text Available Se evaluó la capacidad del sistema API Coryne, versión 2.0, (bioMérieux para identificar 178 cepas de bacilos gram-positivos: 78 del género Corynebacterium y 100 de géneros relacionados, aislados de muestras clínicas de pacientes atendidos en el Hospital de Clínicas José de San Martín (UBA en el período 1995-2004. Los aislamientos fueron identificados de acuerdo al esquema de von Graevenitz y Funke. Sobre un total de 178 cepas, 162 (91% fueron correctamente identificadas a nivel de género y especie (IC95 = 85,6- 94,6 , 44 de ellas (24,7% requirieron el uso de pruebas adicionales para la identificación definitiva. En 16 cepas (9% no se llegó a la identificación correcta (IC95= 5,4-14,4 y no hubo cepas no identificadas. API Coryne versión 2.0 es un sistema útil para la identificación de la mayoría de las especies de Corynebacterium de importancia clínica: Corynebacterium jeikeium, Corynebacterium urealyticum, Corynebacterium striatum, Corynebacterium pseudodiphtheriticum, Corynebacterium amycolatum y de las especies relacionadas Arcanobacterium haemolyticum, Dermabacter hominis, Listeria monocytogenes, entre otros. No obstante para bacilos gram-positivos difteroides que presentan pigmento amarillo (Aureobacterium spp, Leifsonia aquatica, Microbacterium spp. y Cellulomonas spp. y para bacilos gram-positivos ácido resistentes (Rhodococcus, Gordonia, Tsukamurella y Nocardia, la utilidad en la identificación del género es limitada.The ability of the API Coryne system, version 2.0, to identify 178 strains of gram-positive rods was evaluated. Seventy eight isolates belonged to genus Corynebacterium and one hundred to related genera, all strains were isolated from clinical samples at the Laboratory of Bacteriology, Hospital de Clínicas José de San Martín (UBA between 1995 and 2004.The isolates were identified according to von Graevenitz and Funke&'s scheme. One hundred and sixty two out of 178 strains (91% were correctly

  12. Actualización de la resistencia a antimicrobianos de bacilos Gram negativos aislados en hospitales de nivel III de Colombia: años 2006, 2007 y 2008

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    David Felipe Briceño

    2010-09-01

    Conclusiones. Los programas de vigilancia pueden tener un impacto en la disminución significativa de gérmenes multirresistentes, ya que contribuyen a la adecuada implementación de protocolos encaminados a fortalecer las estrategias de control de infecciones y el manejo racional de antibióticos en cada hospital.

  13. Perfil de susceptibilidade a antimicrobianos em amostras de cocos Gram-positivos, catalase negativos, isoladas de mastite subclínica bubalina Profile of antimicrobial susceptibility in strains of Gram positive cocos, negative catalase, isolated from buffalo subclinical mastitis

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    Maria C.E. Vianni

    2003-06-01

    Full Text Available Estudou-se o perfil de susceptibilidade a antimicrobianos em cocos Gram-positivos catalase negativos (21 amostras de Lactococcus garvieae e 6 de Enterococcus gallinarum, isoladas do leite de fêmeas com mastite subclínica e pertencentes a uma população composta por seis rebanhos bubalinos localizados no Estado do Rio de Janeiro. O teste utilizado foi o da difusão de discos em agar Müller Hinton, segundo recomendações do National Committee for Clinical Laboratory Standards - NCCLS, tendo sido testados discos com ampicilina (10mg, cefalotina (30mg, cefotaxima (30mg, cefoxitina (30mg, cloranfenicol (30mg, eritromicina (15mg, gentamicina (10mg, nitrofurantoína (300mg, norfloxacina (10mg, penicilina (10 UI, tetraciclina (30mg e vancomicina (30mg. Os resultados evidenciaram que em se tratando de Lactococcus garvieae, o antimicrobiano mais eficiente foi o nitrofurantoína com 85,71% de sensibilidade, seguido da cefotaxima (61,90%, vancomicina (52,38%, norfloxacina (47,62% e cefalotina (47,62%. A maior resistência foi desenvolvida frente a penicilina e ampicilina, com 95,24% de resistênciapara os dois antimicrobianos testados. O perfil de susceptibilidade desenvolvido pelas amostras de Enterococcus gallinarum, mostrou baixa sensibilidade frente aos antimicrobianos testados, onde os maiores índices foram observados frente eritromicina e gentamicina, com 33,34% de sensibilidade para ambos; quanto à resistência desenvolvida, foi possível observar 100% de resistência com relação a vancomicina e tetraciclina, seguindo-se cloranfenicol, penicilina, ampicilina, cefoxitina, cefalotina, cefotaxima, norfloxacina e nitrofurantoína, todas evidenciando uma resistência de 83,33% das amostras testadas.The susceptibility of antimicrobials was studied in Gram positive and catalase negative cocci (21 samples of Lactococcus garvieae and 6 Enterococcus gallinarum, isolated from the milk of cows with subclinical mastitis, belonging to six buffalo herds in

  14. El spot electoral negativo

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    Palma Peña-Jiménez

    2011-01-01

    Full Text Available l spot político tiene durante la campaña un objetivo final inequívoco: la consecución del voto favorable. Se dirige al cuerpo electoral a través de la televisión y de Internet, y presenta, en muchos casos, un planteamiento negativo, albergando mensajes destinados a la crítica frontal contra el adversario, más que a la exposición de propuestas propias. Este artículo se centra en el análisis del spot electoral negativo, en aquellas producciones audiovisuales construidas sin más causa que la reprobación del contrincante. Se trata de vídeos que, lejos de emplearse en difundir las potencialidades de la organización y las virtudes de su candidato –además de su programa electoral–, consumen su tiempo en descalificar al oponente mediante la transmisión de mensajes, muchas veces, ad hominem. Repasamos el planteamiento negativo del spot electoral desde su primera manifestación, que en España data de 1996, año de emisión del conocido como vídeo del dóberman, sin olvidar otros ejemplos que completan el objeto de estudio.

  15. Bactérias gram-negativas em cardeais (Paroaria coronata e Paroaria dominicana apreendidos do tráfico de animais silvestres

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    Marcos Paulo Vieira Cunha

    2016-04-01

    Full Text Available Anualmente o tráfico de animais silvestres retira milhões de aves da natureza. Os cardeais (Paroaria coronata e cardeais-do-nordeste (Paroaria dominicana estão incluídos entre as espécies de aves mais traficadas. A microbiota cloacal de passeriformes de vida livre é composta principalmente por bacilos e cocos gram-positivos, já os bacilos gram-negativos predominam em aves de cativeiro. Em situações de estresse e baixa de imunidade as bactérias gram-negativas podem causar infecções oportunistas. O presente trabalho identificou bactérias da microbiota da cloaca de 49 espécimes de P. coronata e P. dominicana apreendidas do tráfico de animais silvestres em São Paulo (SP. Foram isoladas treze espécies de bactérias gram-negativas, incluindo Salmonella spp. e Pseudomonas aeruginosa. A maior frequência de ocorrência foi de Escherichia coli, identificada em 42/49 (85,7% das amostras fecais. Dentre os isolados de E. coli, 21/42 pertenciam aos grupos filogenéticos B2 e D, relacionados a estirpes patogênicas que causam doença extraintestinal em humanos. Klebsiella pneumoniae foi isolada em 28/49 (57,1% das amostras. Esses resultados reforçam que as condições estressantes a que esses animais são submetidos em situações de tráfico, incluindo o contato com humanos, podem favorecer a colonização da microbiota cloacal das aves por patógenos, o que representa um risco para a sua reintrodução na natureza considerando-se o possível contato com humanos e outros animais.

  16. Bactérias gram negativas resistentes a antimicrobianos em alimentos Gram-negative bacteria resistant to antibiotics in foods

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    José Cavalcante de Albuquerque Ribeiro Dias

    1985-12-01

    Full Text Available A partir de 154 espécimens de alimentos, representados por hortaliças (alface, leite e merenda escolar, obteve-se o isolamento e identificação de 400 amostras de bacilos Gram negativos. Esta amostragem se distribuiu em 339 enterobactérias (Escherichia, Shigella, Citrobacter, Klebsiella, Enterobacter, Serratia e Proteus e 61 de gêneros afins (Acinetobacter, Flavobacterium, Aeromonas e Pseudomonas. Submetendo-se as culturas aos antimicrobianos: sulfadiazina (Su, estreptomicina (Sm, tetraciclina (Tc, cloranfenicol (Cm, canamicina (Km, ampicilina (Ap, ácido nalidíxico (Nal e gentamicina (Gm, observou-se apenas seis estirpes sensíveis a todas as drogas e sensibilidade absoluta à Gm. A predominância dos modelos Su (27,6% e Su-Ap (39,6% incidiu nas enterobactérias, enquanto que, 18,0% para Ap e 9,8% para Su-Ap foram detectados nos gêneros afins. Para caracterização da resistência foram realizados testes de conjugação e a totalidade das culturas não revelou transferência para o gene que confere resistência ao ácido nalidíxico. Relevantes são as taxas de amostras R+ observadas nos bacilos entéricos, oscilando em torno de 90% (leite e merenda escolar e alface, em torno de 70%From 154 food samples, including vegetables (lettuce, milk and meals served at school it was possible to isolate and identify 400 Gram negative bacilli distributed among 339 enteric bacteria (Escherichia, Shigella, Citrobacter, Klebsiella, Enterobacter, Serratia and Proteus and other 61 non enteric bacilli (Acinetobacter, Flavobacterium, Aeromonas and Pseudomonas. Submitting this cultures to the drugs sulfadiazine (Su, streptomycin (Sm, tetracycline (Tc, chloramphenicol (Cm, kanamycin (Km, ampicillin (Ap, nalidixic acid (Nal and gentamycin (Gm it was observed only six stocks susceptible to all drugs and total sensibility to Gm. Among enteric bacteria the profiles Su (27,6% and Su-Ap (39,6% predominated, while for the non enteric bacilli percentages of 18.0 for

  17. Antagonismo del colibacilo y el bacilo de Koch en presencia del acido sulfosalicílico

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    Leonor Martínez Cáceres

    1950-08-01

    Full Text Available Desde 1947, varios investigadores suizos señalaron las propiedades antagónicas, in vitro, de ciertas cepas de bacilo coli contra el bacilo tuberculoso de los tipos: Humano, Bovino, Gallináceo y Pisciario. Posteriormente Hesse y Jahnke (1 comunicaron sus experiencias clínicas de tratamiento de enfermos tuberculosos con suspensiones de bacilo coli y señalaron resultados muy alentadores en cuanto a signos radiológicos, cuadro hemático, sedimentación baciloscopia, aumento de peso y curva térmica. Con el objeto de comprobar el antagonismo que pudiera existir entre las cepas de bacilo Coli y bacilo Tuberculoso en nuestro medio además con el ánimo de hallar una cepa Coli activa, que sirviera para experiencias clínicas posteriores, se llevó a cabo una serie de experiencias in vitro, cuyos resultados son el objeto de esta publicación. Simultáneamente se investigó la influencia del ácido sulfosalicílico sobre el desarrollo de los bacilos en cuestión.

  18. Ideas sobre el posible uso de la pancreatina en la bacteriologia del bacilo de Hansen

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    Arturo O'Byrne

    1941-02-01

    Full Text Available Inicio esta "ideas" transcribiendo lo relativo a la "Constitución química del bacilo de la lepra" por Jeanselme. "Emprendido este estudio por P. G. Unna y sus alumnos, este estudio ha sido continuado por su hijo mediante la aplicación del método llamado "Leprahacks" que consiste en tomar fragmentos cutáneos sobre lesiones lepromatosas, reducirlas a polvo, mezclarlas con agua destilada, centrifugar el líquido lechoso así obtenido y extender el sedimento sobre portaobjeto. El éter y el cloroformo producen el alargamiento, el crecimiento o aumento de volumen, el estado sinuoso o la reducción de volumen del cuerpo bacilar y determinan la formación de lagunas, lo que conduce a UNNA, junior, a admitir que en los bacilos se suceden alternativamente, partes, unas ricas y otras pobres en grasas. La lejía de potasa ejerce, en general, una acción mucho más intensa. Hace desaparecer los bacilos en un tiempo relativamente corto. Los granos de LUTZ resisten durante mucho mayor tiempo a los procedimientos de extracción que las otras partes del bacilo.

  19. Nitrito urinário e infecção do trato urinário por cocos gram-positivos Urinary nitrite and urinary-tract infection by gram-positive cocci

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    Andréa de Fátima Sato

    2005-12-01

    Full Text Available INTRODUÇÃO: A infecção do trato urinário (ITU é uma das mais comuns na clínica médica. Os testes que utilizam tiras reagentes detectam significativamente mais infecções por bactérias gram-negativas do que por espécies gram-positivas, uma vez que o teste de nitrito não revela a presença de patógenos gram-positivos em muitos casos. OBJETIVOS: Explorar a microbiologia e a freqüência de infecção urinária por cocos em adultos sintomáticos, relacionando-as com o resultado de nitrito urinário, para traçar o perfil epidemiológico desses pacientes. MATERIAL E MÉTODO: Um estudo retrospectivo foi conduzido na Secretaria de Saúde do município de Maringá-PR, no período de abril de 2004 a março de 2005. RESULTADOS: Amostras de urina de 3.426 pacientes foram coletadas e analisadas. Um total de 448 (13,1% amostras foi positivo para cultura. Em 388 (86,6% casos houve crescimento de bacilos gram-negativos (BGN e em 60 (13,4% casos, cocos gram-positivos (CGP. A análise estatística de co-morbidades revelou diferença significativa na proporção de pacientes com hipertensão (31,3% com nitrito positivo versus 4,5% com nitrito negativo, p BACKGROUND: Urinary tract infection (UTI is among the most common infections in medical center. Urinalysis tests detect significantly more gram-negative infections than those due to gram-positive bacteria because the urinary nitrite test does not detect the presence of gram-positive pathogens in many cases. OBJECTIVES: Explore the microbiology and frequency of UTI by coccus in symptomatic adult patients, comparing them with urinary nitrite results, in order to delineate the epidemiological profile of these patients. MATERIAL AND METHOD: Retrospective analysis was conducted from April 2004 through March 2005 at Health Center, Maringa, Brazil. RESULTS: Urine specimens from 3,426 patients were collected and examined. A total of 448 (13.1% samples had positive culture results. There were 388 (86

  20. Gram staining.

    Science.gov (United States)

    Coico, Richard

    2005-10-01

    Named after Hans Christian Gram who developed the method in 1884, the Gram stain allows one to distinguish between Gram-positive and Gram-negative bacteria on the basis of differential staining with a crystal violet-iodine complex and a safranin counterstain. The cell walls of Gram-positive organisms retain this complex after treatment with alcohol and appear purple, whereas gram-negative organisms decolorize following such treatment and appear pink. The method described here is useful for assessing bacterial contamination of tissue culture samples or for examining the Gram stain status and morphological features of bacteria isolated from mixed or isolated bacterial cultures.

  1. Consecuencias en España del aislamiento del bacilo de Koch en la tuberculosis bovina (1882-1901)

    OpenAIRE

    Gutiérrez García, José Manuel

    2001-01-01

    El año más importante para la investigación de la tuberculosis fue 1882 en que Robert Koch descubrió el bacilo causante de tan desastrosa dolencia, identificado en material tuberculoso tanto humano como animal, y que confirmaba la unidad de la tisis en el hombre y en los animales y el hecho del contagio ante el mundo científico.

  2. Pleural fluid Gram stain

    Science.gov (United States)

    Gram stain of pleural fluid ... mixing it with a violet stain (called a Gram stain). A laboratory specialist uses a microscope to ... reveals an abnormal collection of pleural fluid. The Gram stain can help identify the bacteria that might ...

  3. Novos cultivos cromogênicos de bacilos ácido-alcool resistentes isolados de mosquitos (Culicini, capturados sobre leprosos: II nota

    Directory of Open Access Journals (Sweden)

    Celso S. C. Rossell

    1947-12-01

    Full Text Available 1. O autor obteve três novas culturas de bacilos ácido-alcool resisten¬tes, isolados de mosquitos (Culicini capturados sôbre leprosos, em condições naturais, no campo livre a um quilômetro aproximadamente de distância da Colônia Santa Fe. 2. As semeaduras praticadas com mosquistos normais,, capturados sôbre um cavalo, até hoje foram negativas, para bacilos ácido-alcool resistentes. 3. Os exames microscópicos de esfregaços de diferentes tribus de mosquitos silvestres, capturados em condições naturais, sôbre enfermos lepro-matosos, nas margens do rio "Peixe", deram um total de 22% de positivos, com 111 bacilos contaveis e algumas massas de bacilos ácido-alcool resistentes na laminas observadas. (V. quadro I. 4. Os mosquitos urbanos Cutex fatigans, capturados dentro da Colônia nos Pavilhões e vivendas isoladas com lepromatosos, deram um total de 20% de positivos, com 55 bacilos contaveis e alguns grupos de bacilos e globias de bacilos ácido-alcool resistentes. (V. quadro II. 5. Em 50 laminas com esfregaços de mosquitos Culicini normais, cap¬turados sôbre cavalo, encontramos uma só lamina 4 bacilos duvidosos. No resto, as laminas foram negativas para bacilos ácido-alcool resistentes. Estes estudos estão sendo continuados no Laboratório de Leprologia do Instituto Oswaldo Cruz. Assim também temos empreendido novas experiências trabalhando com mosquitos capturados sôbre leprosos nas proximidades do Hospital-Colônia Curupaity e com mosquitos capturados nos Pavilhões do Leprosário, contando com a colaboração do Prof. Oliveira Castro, na classificação do material, determinando rigorosamente as espécies dos mosquitos.The A. describes three new samples of cultures of acid-fast bacilli iso¬lated from wild mosquitos experimentally fed on active cases of leprosy, in the South of the State of Minas Gerais, about 1 mile dintant from Santa Fé Leper Colony. All those cultures are chromogenic and germinate quite well on

  4. Endocervical gram stain

    Science.gov (United States)

    ... no symptoms. Alternative Names Gram stain of cervix; Gram stain of cervical secretions References Marrazzo JM, Apicella MA. Neisseria gonorrhoeae (gonorrhea). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, Updated Edition . 8th ...

  5. Pensamientos automáticos negativos en el dolor crónico

    OpenAIRE

    Cano García, Francisco Javier; Rodríguez Franco, Luis

    2002-01-01

    El análisis de los pensamientos automáticos negativos se ha revelado como elemento clave en la vivencia y manejo del dolor crónico. Ante la inexistencia de instrumentos validados en nuestro entorno, adaptamos el Inventario de Pensamientos Negativos en Respuesta al Dolor (INTRP) sobre una muestra de 205 pacientes de dolor crónico heterogéneo procedentes de diversos centros sanitarios públicos de la provincia de Sevilla (España). Se comprobó la fiabilidad y validez del inventario mediante vario...

  6. La logística del frío negativo, particularidades y dificultades

    OpenAIRE

    Marenco Martínez, Carmen Carolina

    2015-01-01

    El Trabajo Fin de Máster “La logística del frío negativo, particularidades y dificultades”, tiene como objetivo estudiar los costes y las dificultades operativas que conlleva la creación de una empresa especializada en la gestión de la cadena de suministros de frío negativo. Para ello, se realizó un análisis de las instalaciones de un operador logístico especializado en esta materia, en un zona concreta del país centroamericano de El Salvador. Al establecer las particularidades que conllev...

  7. N-Gram models

    NARCIS (Netherlands)

    Hiemstra, Djoerd; Liu, Ling; Tamer Özsu, M.

    2017-01-01

    In language modeling, n-gram models are probabilistic models of text that use some limited amount of history, or word dependencies, where n refers to the number of words that participate in the dependence relation.

  8. Stool Gram stain

    Science.gov (United States)

    ... of stool; Feces Gram stain References Allos BM. Campylobacter infections. In: Goldman L, Schafer AI, eds. Goldman- ... Bacterial Infections Read more Foodborne Illness Read more Gastroenteritis Read more A.D.A.M., Inc. is ...

  9. Estereotipos negativos hacia la vejez en personas mayores de Latinoamérica

    Directory of Open Access Journals (Sweden)

    Viviana X. Lasagni Colombo

    2014-03-01

    Full Text Available Introducción: Los objetivos del estudio se centran en investigar la presencia de estereotipos hacia la vejez en adultos mayores de diez países de Latinoamérica. Comparar el nivel de estereotipos entre países y evaluar la influencia de variables socio-demográficas en la formación de estereotipos. Metodología: Se realizó un estudio descriptivo transversal en adultos mayores de 60 a 70 años (N: 965 residentes en diez países de Latinoamérica. Se aplicó el Cuestionario de Estereotipos Negativos hacia la Vejez (CENVE y se estudió las posibles asociaciones entre variables socio demográficas y los factores del CENVE a través del análisis de varianzas (ANOVA. Los resultados demuestran que existen estereotipos negativos hacia la vejez en las personas mayores siendo más baja la presencia de estos en el factor motivacional. Se comprobó la relación significativa con variables “ocupación” y “nivel de escolaridad” y se corroboró la diferencia en la presencia de estereotipos negativos hacia la vejez entre los países que conforman este estudio. Conclusión: existen estereotipos negativos hacia la vejez en las personas mayores con diferencias entre grupos de países fundamentalmente por las condiciones sociosanitarias, educativas y económicas por las que atraviesan. El nivel de escolaridad y la situación socioeconómica influyen en la construcción de estereotipos negativos hacia la vejez.

  10. Relações entre afetos positivos e negativos e os cinco fatores de personalidade

    Directory of Open Access Journals (Sweden)

    Ana Paula Porto Noronha

    2015-06-01

    Full Text Available ResumoA presente pesquisa tem como objetivo verificar a existência de associações entre afetos positivos e negativos e os fatores de personalidade, sob a perspectiva do modelo dos Cinco Grandes Fatores. Colaboraram para o desenvolvimento do estudo 529 estudantes do Ensino Médio de escolas públicas e particulares com idades entre 14 a 27 anos (M = 16,0; DP = 1,48. No que se refere ao sexo 223 (42,2% eram homens e 306 (57,8%, mulheres. Foram aplicadas a Escala de Afetos Zanon (EAZ e a Bateria Fatorial de Personalidade (BFP. Dentre os resultados, a relação entre o fator neuroticismo e os afetos negativos gerou o coeficiente mais forte (r = 0,62. Em relação aos afetos positivos, a maior correlação se deu com o fator extroversão (r = 0,42. Verificou-se que neuroticismo é o melhor preditor dos afetos negativos, enquanto que extroversão dos afetos positivos. Os achados são discutidos à luz da literatura.

  11. Ghost mycobacteria on Gram stain.

    Science.gov (United States)

    Trifiro, S; Bourgault, A M; Lebel, F; René, P

    1990-01-01

    The Gram stain is a key tool in diagnostic microbiology. Its usefulness with respect to mycobacteria is undefined. The neutrality of mycobacteria other than Mycobacterium tuberculosis on Gram staining of various clinical specimens is described. Images PMID:1688872

  12. Ghost mycobacteria on Gram stain.

    OpenAIRE

    Trifiro, S; Bourgault, A M; Lebel, F; René, P

    1990-01-01

    The Gram stain is a key tool in diagnostic microbiology. Its usefulness with respect to mycobacteria is undefined. The neutrality of mycobacteria other than Mycobacterium tuberculosis on Gram staining of various clinical specimens is described.

  13. Gram stain of urethral discharge

    Science.gov (United States)

    Urethral discharge Gram stain; Urethritis - Gram stain ... Augenbraun MH, McCormack WM. Urethritis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, Updated Edition . ...

  14. Impacto de las redes sociales e internet en la adolescencia: aspectos positivos y negativos

    Directory of Open Access Journals (Sweden)

    L. Elías Arab, Dr.

    2015-01-01

    Full Text Available Este artículo presenta una revisión teórica del impacto, tanto positivo como negativo, de las redes sociales en los adoles- centes y de la relación directa entre esto y el uso o abuso de las nuevas tecnologías. A su vez, se establece el vínculo entre las formas de utilizarlas y las características psicológi- cas individuales, los desarrollos previos de personalidad y el control parental. Se toma como punto de partida el desa- rrollo adolescente asociado a la construcción de la identidad juvenil en el contexto de un nuevo paradigma comunica- cional (cibercomunicación, donde el límite entre lo públi- co y lo privado se torna cada vez más difuso. Se expone la terminología propia de las redes sociales y se pone énfasis en las estrategias de supervisión y control adulto. Se deta- llan los aspectos positivos que las nuevas tecnologías ofre- cen (diversas oportunidades de aprendizaje, entretención, socialización, desarrollo de habilidades, creatividad y me- jora de la motivación al aprendizaje especialmente en ado- lescentes, entre otros y los aspectos negativos asociados (distanciamiento afectivo, pérdida de límites en la comuni- cación y pérdida de la capacidad de escucha, entre otros. Este artículo destaca la necesidad de entregar y estimular modelos de comunicación social reales y una educación en el uso de las nuevas tecnologías. El objetivo es actualizar y orientar a profesionales de la salud sobre los aspectos posi- tivos y/o negativos de las redes sociales en los adolescentes.

  15. Estereotipos negativos hacia la vejez en personas mayores de Latinoamérica

    OpenAIRE

    Colombo, Viviana X. Lasagni; Ministerio de Desarrollo Social y Humano, Dirección de Adultos Mayores, Mendoza (Argentina).; Angarita, Roberto Bernal; Asociación Maestros de la supervivencia. Chia (Colombia); Gatto, María del Rosario Tuzzo; Escuela Universitaria de Tecnología Médica, Facultad de Medicina, Universidad de la República, Montevideo (Uruguay).; Bessolo, María Soledad Rodríguez; Ministerio de Desarrollo Social, Instituto Nacional del adulto mayor; Programa de Gerontología Social, Facultad de Ciencias Humanas, Universidad Católica, Montevideo (Uruguay); Calderón, Dalila Heredia; Universidad Politécnica Salesiana, Quito (Ecuador).; Miranda, Lenny M. Muñoz; Secretaria de Educación y Universidad Incca, Bogotá (Colombia); Guiñazu, Norma Palermo; Municipalidad de General Pueyrredón, Secretaría de Salud, Área de Promoción Gerontológica. División Servicio Social en Salud, Mar del Plata (Argentina); Gutiérrez, Luynés M. Torrealba; Universidad Centro occidental Lisandro Alvarado, Barquisimeto (Venezuela).; Tarifa, Elizabeth Crespo; OMS/OPS, La Paz (Bolivia).; Gavira, Gladys; Instituto de previsión de la Universidad Autónoma INPREUNAH. (Honduras); Palacios, Marcelina; Federación Iberoamericana de Asociaciones de Adultos Mayores (FIAPAM), Asunción (Paraguay).; Campos, Corina Inés Villarroel; Municipalidad de Quintero, Valparaíso (Chile).; Fahmy, Walid Makin; Hospital Municipal y Maternidad Dr. Odelmo Leão Carneiro, UberlÂndia (MG, Brasil); Unidad de Atención Integrada UAI, Pampulha, Uberlandia (MG, Brasil).; Baietti, Ana Charamelo; Departamento de Geriatría, Hospital de Clínicas, Facultad de Medicina, Universidad de la República, Montevideo (Uruguay).; Veiga, Pura Díaz; Fundación Grupo Matia. Madrid (España).

    2014-01-01

    Introducción: Los objetivos del estudio se centran en investigar la presencia de estereotipos hacia la vejez en adultos mayores de diez países de Latinoamérica. Comparar el nivel de estereotipos entre países y evaluar la influencia de variables socio-demográficas en la formación de estereotipos. Metodología: Se realizó un estudio descriptivo transversal en adultos mayores de 60 a 70 años (N: 965) residentes en diez países de Latinoamérica. Se aplicó el Cuestionario de Estereotipos Negativos h...

  16. Moldes contrários: o romantismo como modelo (negativo) para o naturalismo

    OpenAIRE

    DA SILVA, Alan Victor Flor; SALES, Germana Maria Araújo

    2014-01-01

    Modelos negativos são paradigmas com os quais não desejamos ser comparados, aos quais queremos nos contrapor ou dos quais esperamos ser diferentes. Considerando-se, portanto, esse conceito, a partir dos romances O Mulato (1881), de Aluísio de Azevedo, A Normalista (1893), de Adolfo Caminha, e Hortência (1888), de Marques de Carvalho, objetivamos, com este trabalho, demonstrar que os idealizadores do Naturalismo no Brasil atribuem ao Romantismo, ainda que de forma negativa, a função de modelo....

  17. Impacto de las redes sociales e internet en la adolescencia: aspectos positivos y negativos

    OpenAIRE

    L. Elías Arab, Dr.; G. Alejandra Díaz, Ps.

    2015-01-01

    Este artículo presenta una revisión teórica del impacto, tanto positivo como negativo, de las redes sociales en los adoles- centes y de la relación directa entre esto y el uso o abuso de las nuevas tecnologías. A su vez, se establece el vínculo entre las formas de utilizarlas y las características psicológi- cas individuales, los desarrollos previos de personalidad y el control parental. Se toma como punto de partida el desa- rrollo adolescente asociado a la construcción de la identidad juven...

  18. Cognición y síntomas negativos en la esquizofrenia

    OpenAIRE

    Bagney Lifante, Alexandra

    2016-01-01

    Aunque los delirios y alucinaciones, también denominados síntomas positivos, se han considerado como los más característicos de la esquizofrenia y tradicionalmente han supuesto la diana de los tratamientos para el trastorno, hoy en día se conoce que no son éstos los síntomas más ligados al pronóstico y funcionalidad de los pacientes. En los últimos años se ha puesto de manifiesto que los denominados síntomas negativos (que incluyen aspectos como la abulia, la asociabilidad, la anhedonia, la a...

  19. Four grams of glucose

    OpenAIRE

    Wasserman, David H.

    2008-01-01

    Four grams of glucose circulates in the blood of a person weighing 70 kg. This glucose is critical for normal function in many cell types. In accordance with the importance of these 4 g of glucose, a sophisticated control system is in place to maintain blood glucose constant. Our focus has been on the mechanisms by which the flux of glucose from liver to blood and from blood to skeletal muscle is regulated. The body has a remarkable capacity to satisfy the nutritional need for glucose, while ...

  20. Granulomas do pênis: uma complicação rara da terapia intravesical com Bacilo Calmette-Guérin Granulomas of the penis: a rare complication of intravesical therapy with Bacillus Calmette-Guerin

    Directory of Open Access Journals (Sweden)

    Sara Isabel Alcântara Lestre

    2011-08-01

    Full Text Available A imunoterapia com o Bacilo Calmette-Guérin é amplamente usada no tratamento e profilaxia da neoplasia urotelial superficial. As complicações associadas ao tratamento são comuns. Os autores relatam um caso de inflamação granulomatosa do pênis, associada à terapia intravesical com Bacilo Calmette-Guérin, com múltiplos nódulos eritematosos indolores localizados na glande. É também efetuada uma revisão da literatura. A balanopostite granulomatosa é uma complicação rara associada à imunoterapia com Bacilo Calmette-Guérin, com uma apresentação clinicamente heterogênea que pode dificultar o diagnóstico. O seu reconhecimento clínico é essencial para o início precoce de tuberculostáticos e interrupção de Bacilo Calmette-GuérinImmunotherapy with Bacillus Calmette-Guérin is widely used for treatment and prophylaxis of superficial urothelial cancer. Complications associated with Bacillus Calmette-Guérin treatment are common. The authors describe a case of granulomatous inflammation of the penis associated with intravesical Bacillus Calmette-Guérin therapy, presenting with multiple erythematous and painless nodules located on the glans. A review of the literature is also performed. Granulomatous balanoposthitis is a rare complication of Bacillus Calmette-Guérin immunotherapy, with heterogeneous clinical presentation, which can make the diagnosis difficult. Its clinical recognition is essential for early start of therapy with antitubercular agents and interruption of Bacillus Calmette-Guérin

  1. Isolamento e estudo experimental de duas novas culturas de bacilos ácido-alcool resistentes de muco nasal de leprosos

    Directory of Open Access Journals (Sweden)

    H. C. de Souza-Araujo

    1954-03-01

    Full Text Available The A. described on December 14, 1951, his first culture of acid-fast bacillus isolated from nasal mucus of a leprous girl. in this paper the A. describes two new strains of acid-fast bacilli gotten also from nasal mucus of other two leprous girls, L3 cases. The first patient (layse S had her mucus treated by petroff's method on December 16, 1952 and sown onto three tubes of loewenstein medium and in glycerin broth. After two weeks incubation at 37°C all three tubes of Loewenstein showed many punctiforme and pin-head yellowish colonies, whose microscopic examination proved to be of a pure acid-fast bacillus culture. This sample inoculated in rats and mice produced, after 55 days incubation, small tumors from which the culture was easily recovered. On April, 9, 1953 a new sample of nasal mucus of the same patient was sown in three tubes of Loewenstein. After two weeks incubation at 37°C all 3 tubes showed germination of small yellowish colonies of acid-fast bacilli. Within four months being gotten two samples of identical cultures in all smeared tubes of Loewenstein medium sown, proved that such cultures were not an ordinary ambient contamination. Second patient: - Maria N. After various sowing of different kinds of material from her, february 26, 1953 her nasal mucus treated by soda and sown onto Loewenstein medium, after 25 days incubation showed in only one tube, one small round colony, at first white, becoming creamy after three months. Transplants in various media grew at first slowly and after 2 or 3 generations grew faster. The "Layse" strain produced pellicle in glycerin broth and Dubos medium; the "Maria N." strain did not produce as yet. Both strains (Layse I and II, and Maria N. gave weak positive Dubos test in half-an-hour and negative after 24 hours reading. Both were strongly positive when stained by Gram, Ziehl-Neelsen and Fontes methods. Both strains gave also positive fluoroscopy. These cultures are being studied. The A

  2. Gram-negative and Gram-positive bacterial extracellular vesicles.

    Science.gov (United States)

    Kim, Ji Hyun; Lee, Jaewook; Park, Jaesung; Gho, Yong Song

    2015-04-01

    Like mammalian cells, Gram-negative and Gram-positive bacteria release nano-sized membrane vesicles into the extracellular environment either in a constitutive manner or in a regulated manner. These bacterial extracellular vesicles are spherical bilayered proteolipids enriched with bioactive proteins, lipids, nucleic acids, and virulence factors. Recent progress in this field supports the critical pathophysiological functions of these vesicles in both bacteria-bacteria and bacteria-host interactions. This review provides an overview of the current understanding on Gram-negative and Gram-positive bacterial extracellular vesicles, especially regarding the biogenesis, components, and functions in poly-species communities. We hope that this review will stimulate additional research in this emerging field of bacterial extracellular vesicles and contribute to the development of extracellular vesicle-based diagnostic tools and effective vaccines against pathogenic Gram-negative and Gram-positive bacteria. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Microbiota periodontal y microorganismos aislados de válvulas cardiacas en pacientes sometidos a cirugía de reemplazo de válvulas en una clínica de Cali, Colombia

    Directory of Open Access Journals (Sweden)

    Sandra Moreno

    2017-12-01

    Conclusiones. La microbiota periodontal de pacientes sometidos a cirugía de reemplazo valvular estaba conformada por especies Gram negativas que han sido relacionadas con infecciones en tejidos extraorales; sin embargo, no se encontraron agentes patógenos periodontales en los tejidos de las válvulas. Aunque hubo muestras de estos tejidos y subgingivales, positivas para bacilos entéricos Gram negativos, no es posible asegurar que tuvieran el mismo origen filogenético.

  4. RELACIONES ENTRE AFECTOS POSITIVOS Y NEGATIVOS E INTERESES PROFESIONALES EN UNIVERSITARIOS

    Directory of Open Access Journals (Sweden)

    Ana Paula Porto Noronha

    2015-01-01

    Full Text Available El presente estudio investigó la relación entre afectos positivos y negativos e intereses profesionales. Además fueron evaluadas diferencias presentadas debido al curso. Participaron 76 estudiantes universitarios, siendo 51,3% del curso de Psicología y 48,7% de Pedagogía. En cuanto al sexo, 89,5% de los participantes eran mujeres y el promedio de edad fue de 22,83 años. Los afectos fueron evaluados por la “Escala de Afetos Zanon” y los intereses, por el “Questionário de Busca Auto-Dirigida”. Los resultados revelaron que los afectos positivos correlacionaron con los tipos Social, Investigativo, Emprendedor y Realista, con magnitudes bajas. En cuanto a las diferencias de promedio entre los cursos, hubo en relación al tipo Social, siendo que los participantes de Psicología obtuvieron promedios superiores. Los resultados son discutidos a la luz de la literatura.

  5. Evaluación de bacilos aerobios formadores de endosporas (bafes) para el control biológico de Rhizoctonia solani Kuhn en el cultivo de papa criolla (solanum tuberosum Grupo Phureja)

    OpenAIRE

    Blanco Zapata, Diana Carolina

    2012-01-01

    Rhizoctonia solani es un hongo fitopatógeno que produce la enfermedad de la Rizoctoniasis en cultivos de papa (Solanun tuberosum) a nivel mundial causando reducción en el rendimiento y la producción entre el 10% y el 26% Los mecanismos de control que se utilizan en la actualidad no permiten un control efectivo de la enfermedad, demandan altos costos y generan problemas medioambientales que estimulan a la búsqueda de estrategias alternativas y/o adicionales como el uso de bacilos formadores de...

  6. Bacterial diversity in soil in response to different plans, phosphate fertilizers and liming Diversidade bacteriana do solo em resposta a diferentes plantas, fertilizantes fosfatados e calagem

    Directory of Open Access Journals (Sweden)

    Paulo da Silva

    2002-12-01

    Full Text Available The diversity of bacterial isolates from soil in response to different plants (control, Brachiaria ruziziensis and Cajanus cajan, fertilization (control, simple superphosphate and rock phosphate and liming (with and without lime was evaluated. Phenotypic and physiological characteristics of the isolates were recorded and organized in a file to identify the bacteria. Among the isolates, 95% were Gram-positive and 5% Gram-negative rods. Soil cultivated with B. ruziziensis favored the nonsporing Gram-positive and Gram-negative rods compared to soils with C. cajan or uncultivated. Number of spore-forming Gram-positive rods were higher in plots with superphosphate than in unfertilized soil or soil fertilized with rock phosphate. In unfertilized plots, larger number of Gram-positive cocci and Gram-negative rods was obtained than in fertilized plots. Unlimed plots favored spore-forming Gram-positive rods, Gram-positive cocci and Gram-negative rods, while with liming a larger proportion of nonsporing Gram-positive rods was found. From 7 to 86% of the total isolates utilized different carbohydrates. The recording data used in this experiment was effective in the isolates identification, and might be useful for diagnosis of soil bacteria. Bacillus, Cellulomonas, Rhodococcus, Enterobacter, Flavobacterium, Micrococcus and Arthrobacter were the genera more commonly found. Bacterial diversity was enhanced in limed, unfertilized and plant cultivated plots.Este estudo avaliou a diversidade de bactérias isoladas do solo em resposta a diferentes plantas (controle, Brachiaria ruziziensis e Cajanus cajan, fertilizantes (controle, superfosfato simples e fosfato de rocha e calagem (com e sem calcário. As características fenotípicas e fisiológicas dos isolados foram registradas e organizadas em um arquivo para identificar as bactérias. Entre os isolados, 95% foram de bactérias Gram positivas e 5% bacilos Gram negativos. B. ruziziensis favoreceu mais os bacilos

  7. EFECTOS POSITIVOS Y NEGATIVOS DE LOS MEDIOS DE COMUNICACIÓN SOCIAL

    Directory of Open Access Journals (Sweden)

    Fernando Serpa Florez

    1982-12-01

    Full Text Available

    Un tema amplio fue escogido por la Asociación Latinoamericana de Academias de Medicina. Estudiar los "Efectos Positivos y Negativos de los Medios de Comunicación Social".

    En su conjunto, entre tales medios podríamos englobar el gesto y la palabra, que desde el comienzo de la humanidad han sido usados por el hombre para comunicarse. O incluír, con el descubrimiento de la escritura milenios después, la influencia de ésta sobre la evolución del hombre, cada vez mayor a medida que se fueron inventando técnicas para hacer más fácil su difusión, con la imprenta como paso gigantesco del progreso.

    La cultura se ha enriquecido con estas adquisiciones (con la invención de la palabra podríamos aceptar que la sorprendente evolución de nuestra especie comenzó: "En el principio fue el verbo ... ". y al lado de los factores negativos que tales medios de comunicación han tenido sobre el hombre, sería necio negar que los factores favorables han sido superiores.

    Desde luego, nuestra Asociación, al señalar tan ambiciosa meta, seguramente ha querido (trascendiendo las primeras fases de la vida social en la historia de la humanidad, en las que por centurias el aprendizaje se basó en la transmisión de los conocimientos por medio de leyendas y mitos que quedaron grabados en el inconsciente colectivo y luego, ya en la época histórica, gracias a la lectura, aumentando el acervo cultural de los pueblos con la
    invención del libro que ha permitido conservar las enseñanzas y hacerlas llegar a los hombres en el trasegar tranquilo de las escuelas y las bibliotecas centrar nuestro interés e investigación sobre el impacto que está causando la revolución tecnológica al producir, en virtud principalmente de la electrónica, la "cultura de masas" con la invención del telégrafo, el teléfono, la radiofonía y, por último, la televisión.


    En un comienzo fue la imitación, uniendo las percepciones del ojo y del o

  8. Efeito do glicerol e do telurito de potássio sôbre os grânulos metacromáticos e a morfologia do bacilo diftérico

    Directory of Open Access Journals (Sweden)

    João F. Valeiro

    1969-01-01

    Full Text Available Após ter-se salientado a importância da preservação da morfologia convencional do bacilo diftérico, para os propósitos do diagnóstico presuntivo de difteria, faz-se um estudo comparativo dos aspectos morfológicos de 10 amostras de Corynebacterium em quatro meios de uso mais comum para o isolamento dêsses germes, modificando êsses mesmos meios, em cada caso, pela inclusão de glicerol, de teluríto de potássio e de glicerol e telurito, em comparação com a fórmula original. Descreve-se uma técnica simples para a incorporação do telurito de potássio nos meios preparados por coagulação de proteínas animais (Loeffler e Pai. A apreciação da morfologia e da evidenciação de grânulos de volutina destacam o meio de Pai, com cêrca de 7 porcento de glicerol, entre 16 variações de meios de cultura estudadas, como o mais favorável para a demonstração da morfologia considerada típica no diagnóstico do bacilo diftérico.

  9. Periodical episodes of foaming involving Gram-negative filaments. Morpho type 0581: an unknown; Episodios periodicos de espumacion con impliaciond e filamentos Gram negativos. El morfotipo 0581: un desconido

    Energy Technology Data Exchange (ETDEWEB)

    Zarnoza, A.; Rodriguez, E.; Isac, L.; Alonso, J. L.; Fernandez, N.; Zorrila, F.; Fajardo, V.

    2006-07-01

    The bacteria GALO and Microthrix parvicella are responsible for foaming in active sludge in WWTP. According to Eikelboom (2000) and Jenkins, et al. (2003), these micro-organisms are classified by morpho types, which sometimes show a diversity of species when specific probes are used. A study of the periodical foaming process in the WWTP in the municipally of Torres-Torres (Valencia, Spain), with a predominance of morpho type 0581, has made it possible to ascertain both the optical and phylogenetic identity of this morpho type. Contrary to what might have been expected in view of its morphological similarity to Microthrix parvicella, morpho type 0581 is photogenically related to the phylum Chloroflexi and not to the phylum Actinobacteria, to which Microthrix parvicella belong. (Author)

  10. Engajamento dos Consumidores com o Boca a Boca Eletrônico Negativo em Lojas de Aplicativos Móveis

    Directory of Open Access Journals (Sweden)

    Adrianne Paula Vieira de Andrade

    2017-11-01

    Full Text Available O objetivo do estudo é compreender as motivações do comportamento de engajamento do consumidor com o boca a boca eletrônico (electronic word-of–mouth [eWOM] negativo em plataformas de consumo de aplicativos móveis, utilizando-se como lente de análise a Teoria da Ação Racional (Theory of Reasoned Action [TRA]. Foram realizadas dez entrevistas em profundidade com usuários emissores de comentários negativos, as quais permitiram a construção de um corpus que foi descrito, classificado e interpretado por meio de análise temática de conteúdo. Como generalização analítica, infere-se que os motivadores mais influentes para o engajamento com o eWOM negativo são a Busca por Providências, o Altruísmo, as Emoções Negativas e a Reciprocidade. Com relação aos construtos da TRA, as Atitudes favorecem esse engajamento, mas as Normas subjetivas pouco contribuem para a participação ativa no boca a boca eletrônico negativo. Esta pesquisa pode ajudar os programadores de aplicativos móveis e os analistas de mídias sociais quanto à formulação de estratégias de interação que estimulem o comportamento de engajamento dos consumidores.

  11. Antagonistic effect of brevicin on Gram positive and Gram negative ...

    African Journals Online (AJOL)

    A new low molecular weight brevicin produced by Lactobacillus brevis NS01 has greater antimicrobial activity on Gram positive and negative food borne bacteria. This is stable at high temperature acidic to neutral pH, non proteolytic enzymes and organic solvents. The synergistic effect of brevicin with ...

  12. POLIFONIA EM ENUNCIADOS NEGATIVOS: VOZES QUE HABITAM O DIZER "NÃO" Polyphony in Negative Utterances

    Directory of Open Access Journals (Sweden)

    Décio Orlando Soares da Rocha

    1998-02-01

    Full Text Available O presente artigo centra-se na análise de um questionário aplicado, por ocasião de um programa de treinamento, a um grupo de trabalhadores responsáveis pela supervisão das atividades de operários numa fábrica de produção de pneus situada no Brasil. O questionário deveria revelar o "estilo de liderança" exercido por cada chefe de equipe, sendo consideradas cinco diferentes possibilidades: os estilos autocrata, demagógico, demissionário, mediador e participativo. O perfil participativo é visto pelo autor do questionário como "o mais adequado", uma vez que promoveria a conciliação entre os objetivos pessoais dos operários e os objetivos industriais. Com base numa concepção polifônica dos enunciados negativos, a análise realizada permitiu concluir que, além dos cinco estilos previstos no questionário, um sexto perfil se deixa entrever, o qual parece coincidir com" a voz da empresa". A presença desse sexto perfil explicita a pluralidade e complexidade dos saberes que se atualizam no contexto das interações em situação de trabalho.This paper focuses on the analysis of a written questionnaire administered to a group of foremen working in a tyre factory in Brazil. The questionnaire is designed to reveal the" style of leadership" carried out by each member of the group, among five possible variants: autocratical, demagogical, resigning, mediative and participative. The participative profile is seen by the author of the questionnaire as "the adequate one", in as much as it harmonises workmen’s personal and organisational interests. On the basis of a polyphonic conception of negative utterances the case is made for a more complex view of the questionnaire: beyond the five profiles critically antecipated, a sixth one is contemplated, which seems to coincide clearly with what we call "the voice of the organisation", putting forward different kinds of knowledge in the context of interactions at work.

  13. Differential staining of bacteria: gram stain.

    Science.gov (United States)

    Moyes, Rita B; Reynolds, Jackie; Breakwell, Donald P

    2009-11-01

    In 1884, Hans Christian Gram, a Danish doctor, developed a differential staining technique that is still the cornerstone of bacterial identification and taxonomic division. This multistep, sequential staining protocol separates bacteria into four groups based on cell morphology and cell wall structure: Gram-positive cocci, Gram-negative cocci, Gram-positive rods, and Gram-negative rods. The Gram stain is useful for assessing bacterial contamination of tissue culture samples or for examining the Gram stain status and morphological features of bacteria isolated from mixed or isolated bacterial cultures. (c) 2009 by John Wiley & Sons, Inc.

  14. Relación entre factores psicosociales negativos y el síndrome de Burnout en el personal sanitario de Florencia (Caquetá, Colombia)

    OpenAIRE

    Diana Carolina Silva Henao; Ana Maria Gutiérrez Strauss; Manuel Pando Moreno; Rafael Tuesca Molina

    2014-01-01

    Objetivo: Establecer la relación entre factores psicosociales negativos y el síndrome de burnout en el personal sanitario de Florencia (Caquetá, Colombia), 2012. Materiales y métodos: Estudio transversal. Participaron 300 sujetos de cuatro instituciones de salud de Florencia. Instrumentos: Factores Psicosociales Negativos y el Inventario de Maslach Burnout. Los datos fueron analizados en Epi-info Versión 3.4.3. Se realizó análisis bivariado de factores psicosociales negativos y el síndrome de...

  15. Gramática Hipertextual

    Directory of Open Access Journals (Sweden)

    Francilaine Munhoz Moraes

    2011-07-01

    Full Text Available No meio digital, a construção da notícia se dá pelo hipertexto. Uma linguagem própria ao suporte consolida-se nas duas últimas décadas. Este artigo se dedica a discutir regularidades linguísticas do discurso jornalístico na web. Se há uma linguagem peculiar ao meio, existe também uma gramática correspondente: a gramática hipertextual. Nesse viés, levantamos traços linguísticos da estrutura sintático-semântica, com base na organização da informação em páginas noticiosas eletrônicas. 

  16. Direito a moradia e inclusão social: aspectos positivos e negativos do "programa minha casa minha vida"

    OpenAIRE

    Desordi, Jordana Laís; Strücker, Bianca

    2016-01-01

    O presente artigo pretende analisar aspectos conceituais e doutrinários referentes ao direito à moradia e à inclusão social, fazendo referência aos aspectos positivos e negativos do programa habitacional brasileiro “Minha Casa Minha Vida” (PMCMV). A pesquisa dá ênfase ao PMCMV, momento em que é analisada a legislação que cria e institui o Programa em suas duas versões existentes até este momento. Destaca-se, ainda, os reflexos que o programa causou ao proporcionar o acesso do indivíduo a sua ...

  17. Medicalização dos desvios de comportamento na infância: aspectos positivos e negativos

    Directory of Open Access Journals (Sweden)

    Fabíola Stolf Brzozowski

    Full Text Available A medicalização dos comportamentos desviantes na infância é apresentada como uma estratégia eficaz para lidar com crianças que apresentam algum tipo de dificuldade, sem que, no entanto, as dificuldades desse processo sejam claramente expostas. O processo de medicalização, porém, é complexo e apresenta muitos resultados negativos. Dentro desse contexto, nosso objetivo é refletir sobre essas dificuldades. Primeiramente, apresentamos como se dá a relação entre medicalização e infâcia. Em seguida, discutimos alguns aspectos considerados positivos e negativos da medicalização. Para finalizar, consideramos que enquadrar uma criança em um diagnóstico psiquiátrico apresenta sérias consequências indesejáveis, e acaba sendo mais útil para a sociedade e para o entorno da criança do que para a própria criança.

  18. Veillonella, Firmicutes: Microbes disguised as Gram negatives

    DEFF Research Database (Denmark)

    Vesth, Tammi Camilla; Ozen, Asli; Andersen, Sandra Christine

    2013-01-01

    related to Gram-negative species. Though the Negativicutes stain Gram-negative and possess two membranes, the genome and proteome analysis presented here confirm their place within the (mainly) Gram positive phylum of the Firmicutes. Further studies are required to unveil the evolutionary history...

  19. Usefulness of urinal urinalysis and urine gram stain in the diagnosis of rinary tract infection in hospitalized patients Utilidad del citoquímico y la coloración de Gram en muestras de orina en el diagnóstico de las infecciones del tracto urinario en pacientes hospitalizados.

    Directory of Open Access Journals (Sweden)

    Sergio Jaramillo Velásquez

    2005-04-01

    Gram de orina sin centrifugar, y en 8.008 orinas se hizo la coloración de Gram del sedimento urinario. En comparación con el urocultivo, el citoquímico de orina presentó sensibilidad del 99%, especificidad del 51%, valor predictivo positivo del 60%, y valor predictivo negativo del 98%. La coloración de Gram de la orina sin centrifugar tuvo sensibilidad, especificidad y valores predictivos positivo y negativo de 98%, 73%, 82% y 97%, respectivamente. Para la coloración de Gram del sedimento urinario los valores correspondientes a la sensibilidad, especificidad y valores predictivos positivo y negativo fueron 95%, 78%, 67%, y 97%. Conclusiones: el citoquímico de orina, bajo los criterios propuestos, y la coloración de Gram tienen un alto valor predictivo negativo, que permitiría utilizarlos como pruebas de tamización para determinar la necesidad de solicitar el urocultivo.

  20. Mechanism of gram variability in select bacteria.

    Science.gov (United States)

    Beveridge, T J

    1990-03-01

    Gram stains were performed on strains of Actinomyces bovis, Actinomyces viscosus, Arthrobacter globiformis, Bacillus brevis, Butyrivibrio fibrisolvens, Clostridium tetani, Clostridium thermosaccharolyticum, Corynebacterium parvum, Mycobacterium phlei, and Propionibacterium acnes, using a modified Gram regimen that allowed the staining process to be observed by electron microscopy (J. A. Davies, G. K. Anderson, T. J. Beveridge, and H. C. Clark, J. Bacteriol. 156:837-845, 1983). Furthermore, since a platinum salt replaced the iodine mordant of the Gram stain, energy-dispersive X-ray spectroscopy could evaluate the stain intensity and location by monitoring the platinum signal. These gram-variable bacteria could be split into two groups on the basis of their staining responses. In the Actinomyces-Arthrobacter-Corynebacterium-Mycobacterium-Propionibacterium group, few cells became gram negative until the exponential growth phase; by mid-exponential phase, 10 to 30% of the cells were gram negative. The cells that became gram negative were a select population of the culture, had initiated septum formation, and were more fragile to the stress of the Gram stain at the division site. As cultures aged to stationary phase, there was a relatively slight increase toward gram negativity (now 15 to 40%) due to the increased lysis of nondividing cells by means of lesions in the side walls; these cells maintained their rod shape but stained gram negative. Those in the Bacillus-Butyrivibrio-Clostridium group also became gram negative as cultures aged but by a separate set of events. These bacteria possessed more complex walls, since they were covered by an S layer. They stained gram positive during lag and the initial exponential growth phases, but as doubling times increased, the wall fabric underlying the S layer became noticeably thinner and diffuse, and the cells became more fragile to the Gram stain. By stationary phase, these cultures were virtually gram negative.

  1. Inflamación Granulomatosa Crónica: Métodos de detección de bacilos ácido alcohol resistentes en biopsias embebidas en parafina

    Directory of Open Access Journals (Sweden)

    Javier Andres Bustamante Rengifo

    2010-05-01

    Full Text Available La detección de bacilos ácido alcohol resistentes (BAAR en frotis resulta un aporte significativo al diagnóstico y tratamiento de individuos con inflamación granulomatosa crónica (IGC. Con el objetivo de evaluar la presencia de BAAR en diferentes tejidos de pacientes con IGC demostrada y comparar la frecuencia de los extendidos positivos para BAAR con el grado de formación de granulomas y necrosis, se diseño un estudio retrospectivo, en el que se seleccionaron 57 bloques embebidos en parafina que contenían biopsias de pleura, pulmón, pericardio, ganglio linfático y lóbulo cerebral, correspondientes a 30 pacientes (63.3% hombres, mayores de 18 años, con IGC demostrada y remitidos al departamento de patología del Hospital Universitario del Valle entre el 2002-2008, a cada muestra se le realizaron 3 cortes y se sometieron a tinciones de H/E, Zielh Neelsen y Auramina. La detección de BAAR en frotis fue similar para ambas tinciones especiales en pacientes con IGC necrotizante, reflejando una excelente concordancia en el diagnostico (kappa=0.89, IC95%[0.68-1.0]. Sin embargo, la tinción con Auramina fue superior a la tinción Ziehl Neelsen para la detección de BAAR en pacientes con IGC no necrotizante (kappa=0.65, IC95%[0.23-1.0]. No se encontraron diferencias significativas entre la presencia de BAAR y el tipo de inflamacion, sexo y localización anatómica comprometida. En general, fue buena la concordancia entre los métodos histológicos empleados. Además, se hizo evidente la importancia de implementar el uso de técnicas moleculares mínimamente afectadas por el escaso número de bacilos presentes en las muestras, que finalmente ayudan en el reconocimiento del microorganismo.

  2. Escala de afeto positivo e negativo para crianças: estudos de construção e validação

    Directory of Open Access Journals (Sweden)

    Claudia Hofheinz Giacomoni

    Full Text Available O objetivo deste estudo foi desenvolver uma Escala de Afeto Positivo e Negativo para Crianças. São apresentados dois estudos: de construção da escala, bem como de validação concorrente. Além disso, procurou-se avaliar o nível de afeto positivo e negativo das crianças dessa amostra, assim como, verificar possíveis diferenças entre sexos, faixa etária e tipo de escola. Participaram do estudo de construção da escala 661 crianças (52,2% meninos entre sete e 12 anos (m = 10,6 anos; d.p. = 1,7 anos de escolas públicas estaduais (54% e privadas (46% de Porto Alegre. A versão final da Escala de Afeto Positivo e Negativo é composta por 34 itens, 17 itens em cada subescala. Os coeficientes Alpha obtidos para as subescalas de Afeto Positivo (0,88 e de Afeto Negativo (0,84 apontam evidências de confiabilidade. Análises Fatoriais confirmaram a estrutura da escala através da solução de dois fatores em ambos estudos. A Escala também apresentou boas evidências de validação concorrente. Através de correlações coerentes com as apontadas pela literatura, os resultados indicam que a Escala de Afeto Negativo pode ser utilizada como instrumento de avaliação de desajustamento emocional. O desenvolvimento da Escala de Afeto Positivo e Negativo para Crianças incrementa o processo de elaboração de instrumentos para avaliarmos o bemestar subjetivo infantil.

  3. 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.

  4. Efecto de contraste sucesivo negativo en la valoración emocional de imágenes

    Directory of Open Access Journals (Sweden)

    Lucas Cuenya

    2013-10-01

    Full Text Available Se presentan dos experimentos para estudiar el efecto de la reducción del valor de incentivo sobre las respuestas de tiempo de observación y valoración de la emocionalidad de las imágenes, mediante una escala Likert. En ambos estudios un grupo de sujetos observó una serie de fotografías del Sistema Internacional de Imagen Afectiva (International Affective Picture System, IAPS clasificadas como placenteras de alta activación (fase de pre-cambio y luego, placenteras de baja activación (fase de post-cambio, Grupo Experimental, GE. Otro grupo observó en ambas fases solamente las imágenes placenteras de baja activación (Grupo Control, GC. No hubo efectos en el tiempo de observación de las imágenes pero sí en su valoración emocional. Durante la fase de post-cambio el GE evaluó las imágenes de baja activación como menos emocionales que el GC. El Experimento 2 replica el resultado cuando se interpone una tarea distractora entre cada ensayo de presentación de las imágenes. Estos resultados indican que la valoración afectiva de las imágenes está modulada por efectos de contraste negativo y que su mecanismo es de origen central.

  5. Modeling Martian Dust Using Mars-GRAM

    Science.gov (United States)

    Justh, Hilary L.; Justus, C. G.

    2010-01-01

    Engineering-level atmospheric model widely used for diverse mission applications. Mars-GRAM s perturbation modeling capability is commonly used, in a Monte-Carlo mode, to perform high fidelity engineering end-to-end simulations for entry, descent, and landing (EDL). From the surface to 80 km altitude, Mars-GRAM is based on NASA Ames Mars General Circulation Model (MGCM). Mars-GRAM and MGCM use surface topography from Mars Global Surveyor Mars Orbiter Laser Altimeter (MOLA), with altitudes referenced to the MOLA areoid, or constant potential surface. Traditional Mars-GRAM options for representing the mean atmosphere along entry corridors include: TES Mapping Years 1 and 2, with Mars-GRAM data coming from MGCM model results driven by observed TES dust optical depth TES Mapping Year 0, with user-controlled dust optical depth and Mars-GRAM data interpolated from MGCM model results driven by selected values of globally-uniform dust optical depth. Mars-GRAM 2005 has been validated against Radio Science data, and both nadir and limb data from the Thermal Emission Spectrometer (TES).

  6. Multicenter Assessment of Gram Stain Error Rates.

    Science.gov (United States)

    Samuel, Linoj P; Balada-Llasat, Joan-Miquel; Harrington, Amanda; Cavagnolo, Robert

    2016-06-01

    Gram stains remain the cornerstone of diagnostic testing in the microbiology laboratory for the guidance of empirical treatment prior to availability of culture results. Incorrectly interpreted Gram stains may adversely impact patient care, and yet there are no comprehensive studies that have evaluated the reliability of the technique and there are no established standards for performance. In this study, clinical microbiology laboratories at four major tertiary medical care centers evaluated Gram stain error rates across all nonblood specimen types by using standardized criteria. The study focused on several factors that primarily contribute to errors in the process, including poor specimen quality, smear preparation, and interpretation of the smears. The number of specimens during the evaluation period ranged from 976 to 1,864 specimens per site, and there were a total of 6,115 specimens. Gram stain results were discrepant from culture for 5% of all specimens. Fifty-eight percent of discrepant results were specimens with no organisms reported on Gram stain but significant growth on culture, while 42% of discrepant results had reported organisms on Gram stain that were not recovered in culture. Upon review of available slides, 24% (63/263) of discrepant results were due to reader error, which varied significantly based on site (9% to 45%). The Gram stain error rate also varied between sites, ranging from 0.4% to 2.7%. The data demonstrate a significant variability between laboratories in Gram stain performance and affirm the need for ongoing quality assessment by laboratories. Standardized monitoring of Gram stains is an essential quality control tool for laboratories and is necessary for the establishment of a quality benchmark across laboratories. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  7. Flora microbiana en elaborados de aceitunas verdes en la región de Murcia. Evolución cualitativa durante la fermentación.

    OpenAIRE

    Guzmán Giménez, Ginés; Guevara, L. A.; Laencina Sánchez, José

    1983-01-01

    A lo largo del proceso normal de fermentación en salmuera se estudia en la región de Murcia la flora microbiana de cinco tipos de aceitunas (subvariedades Manzanilla Fina y Carrasqueña, Verdial, Hojiblanca y las variedades Cacereña) sometidas al tratamiento previo de «cocido». La flora heterogénea —que incluye bacterias Gram-negativas, bacterias lácticas y levaduras— con predominio de las poblaciones de bacilos Gram-negativos en los primeros días del proceso fermentati...

  8. Cáncer de mama triple negativo: una enfermedad de difícil diagnóstico y tratamiento

    Directory of Open Access Journals (Sweden)

    Mayer Zaharia

    Full Text Available El cáncer de mama triple negativo (CMTN es una neoplasia maligna caracterizada por la ausencia de la expresión de los receptores de estrógeno, de progesterona y HER2. Estudios recientes han señalado que el CMTN es un grupo heterogéneo de distintas neoplasias, con pronósticos diferentes. Sin embargo, debido a que la realización de perfiles genéticos no es una práctica estándar para el diagnóstico convencional del cáncer de mama, se dificulta la apropiada identificación de este subtipo de cáncer de mama. El CMTN se caracteriza por tener patrones epidemiológicos de alta incidencia en poblaciones afroamericanas y latinas, y de menor incidencia en población caucásica y constituye un problema de salud pública por su elevada morbilidad y mortalidad. Ante la ausencia de blancos terapéuticos, la quimioterapia cumple un rol importante en el tratamiento, y muchos esfuerzos están destinándose a buscar otras combinaciones de quimioterapia y nuevas drogas, mientras que las actuales guías no especifican un tratamiento para este tipo de cánceres. En el presente documento se hace una revisión sobre las características epidemiológicas y clínicas, los posibles factores pronósticos y sobre algunas estrategias terapéuticas contra el CMTN.

  9. Mechanism of gram variability in select bacteria.

    OpenAIRE

    Beveridge, T J

    1990-01-01

    Gram stains were performed on strains of Actinomyces bovis, Actinomyces viscosus, Arthrobacter globiformis, Bacillus brevis, Butyrivibrio fibrisolvens, Clostridium tetani, Clostridium thermosaccharolyticum, Corynebacterium parvum, Mycobacterium phlei, and Propionibacterium acnes, using a modified Gram regimen that allowed the staining process to be observed by electron microscopy (J. A. Davies, G. K. Anderson, T. J. Beveridge, and H. C. Clark, J. Bacteriol. 156:837-845, 1983). Furthermore, si...

  10. Embedded Lattice and Properties of Gram Matrix

    Directory of Open Access Journals (Sweden)

    Futa Yuichi

    2017-03-01

    Full Text Available In this article, we formalize in Mizar [14] the definition of embedding of lattice and its properties. We formally define an inner product on an embedded module. We also formalize properties of Gram matrix. We formally prove that an inverse of Gram matrix for a rational lattice exists. Lattice of Z-module is necessary for lattice problems, LLL (Lenstra, Lenstra and Lov´asz base reduction algorithm [16] and cryptographic systems with lattice [17].

  11. An optimized staining technique for the detection of Gram positive and Gram negative bacteria within tissue.

    Science.gov (United States)

    Becerra, Sandra C; Roy, Daniel C; Sanchez, Carlos J; Christy, Robert J; Burmeister, David M

    2016-04-12

    Bacterial infections are a common clinical problem in both acute and chronic wounds. With growing concerns over antibiotic resistance, treatment of bacterial infections should only occur after positive diagnosis. Currently, diagnosis is delayed due to lengthy culturing methods which may also fail to identify the presence of bacteria. While newer costly bacterial identification methods are being explored, a simple and inexpensive diagnostic tool would aid in immediate and accurate treatments for bacterial infections. Histologically, hematoxylin and eosin (H&E) and Gram stains have been employed, but are far from optimal when analyzing tissue samples due to non-specific staining. The goal of the current study was to develop a modification of the Gram stain that enhances the contrast between bacteria and host tissue. A modified Gram stain was developed and tested as an alternative to Gram stain that improves the contrast between Gram positive bacteria, Gram negative bacteria and host tissue. Initially, clinically relevant strains of Pseudomonas aeruginosa and Staphylococcus aureus were visualized in vitro and in biopsies of infected, porcine burns using routine Gram stain, and immunohistochemistry techniques involving bacterial strain-specific fluorescent antibodies as validation tools. H&E and Gram stain of serial biopsy sections were then compared to a modification of the Gram stain incorporating a counterstain that highlights collagen found in tissue. The modified Gram stain clearly identified both Gram positive and Gram negative bacteria, and when compared to H&E or Gram stain alone provided excellent contrast between bacteria and non-viable burn eschar. Moreover, when applied to surgical biopsies from patients that underwent burn debridement this technique was able to clearly detect bacterial morphology within host tissue. We describe a modification of the Gram stain that provides improved contrast of Gram positive and Gram negative microorganisms within host

  12. Antibacterial activities of β-glucan (laminaran) against gram-negative and gram-positive bacteria

    Science.gov (United States)

    Chamidah, A.; Hardoko, Prihanto, A. A.

    2017-05-01

    This study aimed to determine the antibacterial activity of β-Glucan (laminaran) of LAE and LME extracts from brown algae Sargassum crassifolium using HPMS and Ultrasonication against Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram-negative bacteria (Salmonella typhimurium and Escherichia coli). The highest antibacterial activities of LME extract obtained using the HPMS method against Gram-positive bacteria (B. subtilis and S. aureus) were at 18:10 and 18.80 mm. The ultrasonication method showed a lower inhibition trend than the HPMS method, with MIC and MBC values of 250 mg/ml and 2-8 CFU/ml, respectively, in all Gram-negative and Gram-positive bacteria. The results showed that LME extract at a concentration of 250 mg/mL is bacteriostatic against Gram-positive and -negative bacteria.

  13. CARACTERIZAÇÃO DO STAPHYLOCOCCUS COAGULASE NEGATIVO ISOLADOS DE QUARTOS MAMÁRIOS DE VACAS COM MASTITE SUBCLÍNICA

    Directory of Open Access Journals (Sweden)

    Marlice Teixeira Ribeiro

    1994-01-01

    Full Text Available RESUMO O presente trabalho foi desenvolvido na Zona da Mata - MG, durante três meses. De quatro rebanhos utilizados, trabalhou-se com 16 animais mestiços e 19 holandeses. O objetivo foi caracterizar Staphylococcus coagulase negativos, isolados de quartos mamários de vacas, que inicialmente reagiam à prova do "Califórnia Mastitis Test" (CMT, em quatro testes consecutivos, a intervalo de uma semana. A caracterização das 116 amostras encontradas, correspondentes a Staphylococcus coagulase negativo, foram: S. epidermidis (71,55%, S. hyicus subsp. chromogenes (6,03%, S. simulans (6,03%, S. warneri (4,31%, S. hominis (3,45%, S. cohnii (3,45%, S. sciuri (3,45% e S. haemolyticus (1,73%.

  14. Procedimiento para la gestión de los impactos ambientales negativos asociados a la recuperación de materias primas en Cienfuegos, Cuba.

    Directory of Open Access Journals (Sweden)

    David Javier Castro Rodríguez

    2016-04-01

    Full Text Available El reciclaje constituye una actividad priorizada en Cuba. El objetivo fue implementar un procedimiento para la gestión de los impactos ambientales negativos asociados a los procesos operativos de la Empresa de Recuperación de Materias Primas de Cienfuegos. El procedimiento se construyó utilizando la propuesta del Instituto Andaluz de Tecnología para la gestión por procesos y los ocho pasos en la solución de problemas. Se combinaron herramientas de gestión bajo el principio de convergencia metodológica. Los impactos ambientales fueron evaluados mediante el software GAIA versión 1.0, utilizando los criterios propuestos por la Guía Metodológica de Evaluación de Impacto Ambiental de Conesa. Se identificaron 97 impactos ambientales negativos, entre severos y moderados integraron el 80.41 % de ellos. El factor ambiental más impactado fue el físico-químico con el 50.52 %. El subproceso no metálico resultó el más impactante, con el 50 % de los impactos severos negativos totales y el 34 % de los moderados. Se identificaron las principales causas asociadas y se diseñó un plan de intervención de 35 medidas con base en los principios de Producción Más Limpia. Los resultados contribuyen a lograr la gestión de los impactos ambientales negativos de la entidad y a la sostenibilidad del reciclaje.

  15. El sesgo negativo en la integración de información para calificar el desempeño : Primeros hallazgos

    Directory of Open Access Journals (Sweden)

    Federico León

    1983-06-01

    Full Text Available Replicando hallazgos referidos por la literatura en Psicología Social Experimental, el presente estudio de campo encontró que un sesgo negativo prevaleció en un conjunto de conferencias ofrecidas por 8 psicólogos: la calificación para el conjunto fue significativamente menor que la obtenida para las conferencias tomadas individualmente.Esto ocurrió a pesar del hecho que aproximadamente el 50o/o de los sujetos (N = 50 calificaron más alto el conjunto que las conferencias y se puede explicar por la existencia de mayores diferencias entre las calificaciones del conjunto y las calificaciones individuales de las conferencias en el caso de sesgo negativo (conjunto< conferencias que en el de sesgo positivo (conjunto> conferencias. Dado que diferenciassignificativas entre submuestras de sesgo positivo y negativo fueron constatadas en la calificación del conjunto mas no en la deconferencias tomadas individualmente, se concluyó que el sesgo se produce en el proceso de integración de la información para calificar elconjunto

  16. Relación entre factores psicosociales negativos y el síndrome de Burnout en el personal sanitario de Florencia (Caquetá, Colombia

    Directory of Open Access Journals (Sweden)

    Diana Carolina Silva Henao

    2014-01-01

    Full Text Available Objetivo: Establecer la relación entre factores psicosociales negativos y el síndrome de burnout en el personal sanitario de Florencia (Caquetá, Colombia, 2012. Materiales y métodos: Estudio transversal. Participaron 300 sujetos de cuatro instituciones de salud de Florencia. Instrumentos: Factores Psicosociales Negativos y el Inventario de Maslach Burnout. Los datos fueron analizados en Epi-info Versión 3.4.3. Se realizó análisis bivariado de factores psicosociales negativos y el síndrome de burnout. Resultados: El 8 % presentó alto agotamiento emocional, 27 % baja realización personal y el 12,3 % alta despersonalización. En cuanto a los factores psicosociales negativos, el 61,3 % presentó baja condición en el lugar de trabajo. Alta carga de trabajo en el 7,7 %; el 2,3 % expresó alto contenido y cantidad de la tarea. Se encontró 42 % con alta exigencia laboral, 3 % alto papel laboral y desarrollo de la carrera, 80 % baja interacción social; baja remuneración en el 43,7 %. Para el agotamiento emocional se asoció la carga de trabajo (OR: 2,4, exigencia laboral (OR: 5,4, papel laboral (OR: 3,9, interacción social (OR: 1,9 y remuneración (OR: 2,3. Conclusiones: No se evidencia una prevalencia clásica del síndrome de burnout; la principal dimensión afectada fue la realización personal. Los factores psicosociales negativos asociados requieren estrategias para fomentar un cambio en la satisfacción y la motivación, acompañados de una intervención psicológica y motivacional que promueva un ambiente saludable amparado con una política de estímulos y satisfactores laborales, a partir de la estrategia de la psicología positiva.

  17. Protamine-induced permeabilization of cell envelopes of gram-positive and gram-negative bacteria

    DEFF Research Database (Denmark)

    Johansen, Charlotte; Verheul, A.; Gram, Lone

    1997-01-01

    carboxyfluorescein and ATP after 2 to 5 min. Maximum antibacterial activity was reached at alkaline pH and in the absence of divalent cations. The efficient permeabilization of cell envelopes of both gram-positive and gram-negative bacteria suggests that protamine causes a general disruption of the cell envelope...

  18. Ordered Modified Gram-Schmidt Orthogonalization Revised

    Czech Academy of Sciences Publication Activity Database

    Štuller, Július

    1995-01-01

    Roč. 63, 1/3 (1995), s. 221-227 ISSN 0377-0427. [Modelling' 94. Prague, 29.08.1994-02.09.1994] Keywords : Gram-Schmidt orthogonalization * MGS algorithms * linear algebra Impact factor: 0.373, year: 1995

  19. Revisiting the gram-negative lipoprotein paradigm

    Science.gov (United States)

    The processing of lipoproteins (lpps) in Gram-negative bacteria is generally considered to be an essential pathway. Mature lipoproteins in these bacteria are triacylated, with the final fatty acid addition performed by Lnt, an apolipoprotein n-acyltransferase. The mature lipoproteins are then sorted...

  20. SUPPLEMENTARY INFORMATION A sustainable process for gram ...

    Indian Academy of Sciences (India)

    welcome

    Figure S1: Gram-scale process for the preparation of compound 2h; a) initial stage of the reaction b) end of the reaction c) separation of product from the reaction mixture d) precipitated form of the product e) manual filtration process f) final product ...

  1. Revisiting the Gram-negative lipoprotein paradigm.

    Science.gov (United States)

    LoVullo, Eric D; Wright, Lori F; Isabella, Vincent; Huntley, Jason F; Pavelka, Martin S

    2015-05-01

    The processing of lipoproteins (Lpps) in Gram-negative bacteria is generally considered an essential pathway. Mature lipoproteins in these bacteria are triacylated, with the final fatty acid addition performed by Lnt, an apolipoprotein N-acyltransferase. The mature lipoproteins are then sorted by the Lol system, with most Lpps inserted into the outer membrane (OM). We demonstrate here that the lnt gene is not essential to the Gram-negative pathogen Francisella tularensis subsp. tularensis strain Schu or to the live vaccine strain LVS. An LVS Δlnt mutant has a small-colony phenotype on sucrose medium and increased susceptibility to globomycin and rifampin. We provide data indicating that the OM lipoprotein Tul4A (LpnA) is diacylated but that it, and its paralog Tul4B (LpnB), still sort to the OM in the Δlnt mutant. We present a model in which the Lol sorting pathway of Francisella has a modified ABC transporter system that is capable of recognizing and sorting both triacylated and diacylated lipoproteins, and we show that this modified system is present in many other Gram-negative bacteria. We examined this model using Neisseria gonorrhoeae, which has the same Lol architecture as that of Francisella, and found that the lnt gene is not essential in this organism. This work suggests that Gram-negative bacteria fall into two groups, one in which full lipoprotein processing is essential and one in which the final acylation step is not essential, potentially due to the ability of the Lol sorting pathway in these bacteria to sort immature apolipoproteins to the OM. This paper describes the novel finding that the final stage in lipoprotein processing (normally considered an essential process) is not required by Francisella tularensis or Neisseria gonorrhoeae. The paper provides a potential reason for this and shows that it may be widespread in other Gram-negative bacteria. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  2. Presen?a de Aloanticorpos Eritrocit?rios em gestantes Rh negativo, atendidas na Funda??o de Hematologia e Hemoterapia do Amazonas (Hemoam).

    OpenAIRE

    Cavalcante, Francimary de Oliveira

    2005-01-01

    A presen?a de aloanticorpos irregulares eritrocit?rios da classe G, na circula??o materna, pode causar serias conseq??ncias ao neonato. A aloimunizacao pode ocorrer em diversas situa??es, consideradas de risco, como partos com incompatibilidade sangu?nea, aborto, amniocentese, transfus?es sangu?nea, dentre outras. Neste estudo foi verificada a presen?a de aloanticorpos circulantes regulares e irregulares, em mulheres atendidas no Programa de Gestantes Rh Negativo (PGRhN) da Funda??o de Hemato...

  3. O número negativo na proposição de ensino davydoviana: necessidades para a sua introdução

    Directory of Open Access Journals (Sweden)

    Lucas Sid Moneretto Búrigo

    2016-08-01

    Full Text Available The difficulties presented by Brazilian students in the appropriation of the negative number reported in surveys contributed to this article preparation. Concerned about these difficulties, we turned to Davydov’s proposition, which is the subject of this study. The research problem is: what are the needs created in the particular tasks of Davydov’s educational organization for the introduction of the negative numbers concept, in school situation? It is a qualitative research method in the literature whose source analysis are four tasks presented in the student textbook belonging to Davydov’s proposition. The review process was developed through necessity category: conceptual and pedagogical. The research shows that the need to study the negative numbers is based on the fact that only they enable the resolution of some cases of subtraction and equation. To provide the meaning of opposite to the negative number, the main need is the change from scalar quantities to the vector one. As dificuldades apresentadas por estudantes brasileiros na apropriação do número negativo relatadas em pesquisas contribuíram para a elaboração desse artigo. Preocupados com tais dificuldades, recorremos à proposição davydoviana que é objeto desse estudo. O problema de pesquisa é: quais são as necessidades criadas nas tarefas particulares da organização de ensino davydoviano para a introdução do conceito de número negativo, em situação escolar? Trata-se de uma pesquisa qualitativa na modalidade bibliográfica cuja fonte de análise são quatro tarefas presentes no livro didático do estudante pertencente à proposição davydoviana. O processo de análise se desenvolveu por meio da categoria necessidade: de ordem conceitual e pedagógica. A pesquisa evidencia que a necessidade do estudo dos números negativos decorre de que apenas eles possibilitam a resolução de alguns casos de subtração e equação. Para propiciar o significado de oposto ao

  4. Determinantes celulares, plasmáticos y genéticos de riesgo de trombosis y hemorragia en pacientes con neoplasias mieloproliferativas crónicas filadelfia negativo

    OpenAIRE

    Moreno Belmonte, María José

    2010-01-01

    Las Neoplasias Mieloproliferativas Crónicas Filadelfia negativo clásicas comprenden la trombocitemia esencial, la policitemia vera y la mielofibrosis primaria y se caracterizan por la expansión clonal de la célula madre pluripotente, produciendo como resultado una hipercelularidad medular de predominio de una línea específica; la trombosis y el sangrado son parte de la historia natural de este grupo de enfermedades, constituyendo sus principales causas de morbimortalidad. Trabajos recientes h...

  5. Avaliação de ensaio molecular para determinação de carga viral em indivíduos sorologicamente negativos para o HIV-1

    OpenAIRE

    Pereira,José Moreira; Silva,Cirley Santos da; Porto,Luís Fernando Bruzzi; Póvoa,Luiz Gallotti; Moreira,Aline Santos; Alves,Jorge Roberto

    2002-01-01

    O teste de carga viral foi concebido para acompanhar a evolução e o tratamento do paciente com diagnóstico confirmado de HIV-1. Contudo, sua especificidade diagnóstica não foi ainda avaliada em pessoas que apresentam um teste sorológico negativo. Mesmo assim, ele tem sido erroneamente utilizado para o diagnóstico da infecção primária pelo HIV-1. Este trabalho relata quatro pacientes em que a carga viral plasmática NucliSens (Organon Teknika) foi repetidamente positiva na ausência de anticorpo...

  6. Mid-infrared spectroscopic assessment of nanotoxicity in gram-negative vs. gram-positive bacteria.

    Science.gov (United States)

    Heys, Kelly A; Riding, Matthew J; Strong, Rebecca J; Shore, Richard F; Pereira, M Glória; Jones, Kevin C; Semple, Kirk T; Martin, Francis L

    2014-03-07

    Nanoparticles appear to induce toxic effects through a variety of mechanisms including generation of reactive oxygen species (ROS), physical contact with the cell membrane and indirect catalysis due to remnants from manufacture. The development and subsequent increasing usage of nanomaterials has highlighted a growing need to characterize and assess the toxicity of nanoparticles, particularly those that may have detrimental health effects such as carbon-based nanomaterials (CBNs). Due to interactions of nanoparticles with some reagents, many traditional toxicity tests are unsuitable for use with CBNs. Infrared (IR) spectroscopy is a non-destructive, high throughput technique, which is unhindered by such problems. We explored the application of IR spectroscopy to investigate the effects of CBNs on Gram-negative (Pseudomonas fluorescens) and Gram-positive (Mycobacterium vanbaalenii PYR-1) bacteria. Two types of IR spectroscopy were compared: attenuated total reflection Fourier-transform infrared (ATR-FTIR) and synchrotron radiation-based FTIR (SR-FTIR) spectroscopy. This showed that Gram-positive and Gram-negative bacteria exhibit differing alterations when exposed to CBNs. Gram-positive bacteria appear more resistant to these agents and this may be due to the protection afforded by their more sturdy cell wall. Markers of exposure also vary according to Gram status; Amide II was consistently altered in Gram-negative bacteria and carbohydrate altered in Gram-positive bacteria. ATR-FTIR and SR-FTIR spectroscopy could both be applied to extract biochemical alterations induced by each CBN that were consistent across the two bacterial species; these may represent potential biomarkers of nanoparticle-induced alterations. Vibrational spectroscopy approaches may provide a novel means of fingerprinting the effects of CBNs in target cells.

  7. Gram positive and Gram negative bacteria differ in their sensitivity to cold plasma

    Science.gov (United States)

    Mai-Prochnow, Anne; Clauson, Maryse; Hong, Jungmi; Murphy, Anthony B.

    2016-12-01

    Cold atmospheric-pressure plasma (CAP) is a relatively new method being investigated for antimicrobial activity. However, the exact mode of action is still being explored. Here we report that CAP efficacy is directly correlated to bacterial cell wall thickness in several species. Biofilms of Gram positive Bacillus subtilis, possessing a 55.4 nm cell wall, showed the highest resistance to CAP, with less than one log10 reduction after 10 min treatment. In contrast, biofilms of Gram negative Pseudomonas aeruginosa, possessing only a 2.4 nm cell wall, were almost completely eradicated using the same treatment conditions. Planktonic cultures of Gram negative Pseudomonas libanensis also had a higher log10 reduction than Gram positive Staphylococcus epidermidis. Mixed species biofilms of P. aeruginosa and S. epidermidis showed a similar trend of Gram positive bacteria being more resistant to CAP treatment. However, when grown in co-culture, Gram negative P. aeruginosa was more resistant to CAP overall than as a mono-species biofilm. Emission spectra indicated OH and O, capable of structural cell wall bond breakage, were present in the plasma. This study indicates that cell wall thickness correlates with CAP inactivation times of bacteria, but cell membranes and biofilm matrix are also likely to play a role.

  8. Aspectos negativos no modelo de reporte proposto pela GRI: a opinião das organizações que reportam

    Directory of Open Access Journals (Sweden)

    Thiago Ferreira-Quilice

    2015-12-01

    Full Text Available RESUMO O objetivo neste estudo foi identificar aspectos negativos no modelo de reporte proposto pelo Global Reporting Initiative (GRI, na opinião dos funcionários responsáveis pelo reporte. A importância deste estudo reside no fato de que poucos trabalhos investigam os relatórios de sustentabilidade a partir desse ponto de vista, e por oferecer ao GRI pontos específicos para serem melhorados. A pesquisa foi conduzida por meio da análise de conteúdo das respostas de 27 empresas à seguinte questão: que aspectos negativos você identifica no modelo de reporte proposto pelo GRI? Essa questão foi enviada a todas as empresas brasileiras que publicaram o relatório GRI, referente ao ano-base 2010, entre os anos 2011 e 2013. Como resultado, os respondentes consideraram que as empresas têm dificuldade em entender o modelo proposto pelo GRI, o qual foi considerado complexo, ambíguo e flexível demais, o que dificulta a padronização e a comparação entre os relatórios. Esse fato tem implicações para o GRI, que poderia propor uma metodologia mais simples e menos flexível.

  9. Identificação e caracterização de bacterias psicrotróficas gram-negativas isoladas de tanque de refrigeração por expansão

    OpenAIRE

    Valeriano, Carolina

    2014-01-01

    O objetivo deste trabalho foi identificar a diversidade de microrganismos psicrotróficos Gram-negativos presentes em tanques de expansão comunitários, bem como avaliar a capacidade de produção de enzimas extracelulares e o perfil de resistência a antibiótico destes microrganismos Amostras da superfície de 32 tanques de refrigeração por expansão foram coletadas com auxílio de suabe estéril; destas amostras, 60 isolados foram selecionados e identificadas com auxílio de Kits de identificação API...

  10. Social anxiety and negative early life events in university students Eventos negativos na infância e ansiedade social em estudantes universitários

    Directory of Open Access Journals (Sweden)

    Cynthia Binelli

    2012-06-01

    Full Text Available INTRODUCTION: There is substantial evidence regarding the impact of negative life events during childhood on the aetiology of psychiatric disorders. We examined the association between negative early life events and social anxiety in a sample of 571 Spanish University students. METHODS: In a cross-sectional survey conducted in 2007, we collected data through a semistructured questionnaire of sociodemographic variables, personal and family psychiatric history, and substance abuse. We assessed the five early negative life events: (i the loss of someone close, (ii emotional abuse, (iii physical abuse, (iv family violence, and (v sexual abuse. All participants completed the Liebowitz Social Anxiety Scale. RESULTS: Mean (SD age was 21 (4.5, 75% female, LSAS score was 40 (DP = 22, 14.2% had a psychiatric family history and 50.6% had negative life events during childhood. Linear regression analyses, after controlling for age, gender, and family psychiatric history, showed a positive association between family violence and social score (p = 0.03. None of the remaining stressors produced a significant increase in LSAS score (p > 0.05. CONCLUSION: University students with high levels of social anxiety presented higher prevalence of negative early life events. Thus, childhood family violence could be a risk factor for social anxiety in such a population.INTRODUÇÃO: Existem evidências substanciais sobre o impacto de eventos negativos da vida durante a infância na etiologia dos transtornos psiquiátricos. Examinamos a associação entre os eventos negativos ocorridos na infância e a ansiedade social em uma amostra de 571 estudantes universitários espanhóis. MÉTODOS: Em um estudo transversal realizado em 2007, foram coletados os dados de variáveis sociodemográficas, história psiquiátrica pessoal e familiar e abuso de substâncias por meio de um questionário semiestruturado e avaliamos cinco eventos negativos ocorridos na infância: (i a perda de

  11. Identificação de bactérias não fermentadoras isoladas de pacientes com fibrose cística e em hemoculturas de pacientes internados no HC da Unicamp

    OpenAIRE

    Élio Barreto de Carvalho Filho

    2015-01-01

    Resumo: Introdução: Bacilos gram-negativos não fermentadores (BGN-NFs) são microrganismos que se caracterizam pela incapacidade de utilizar a glicose como fonte de energia pela fermentação, degradando-a pela via oxidativa. A identificação dos BGN-NFs continua sendo um desafio para os laboratórios de rotina em microbiologia pela dificuldade de identificação, em virtude, da baixa ocorrência em amostras ambulatoriais, assim como, pela falta de recursos rápidos, eficientes e pela complexidade e ...

  12. Osteomielitis por Yokenella regensburgei después de una craneotomía en una paciente inmunocompetente

    Directory of Open Access Journals (Sweden)

    Sara Catalina Penagos

    2015-12-01

    Full Text Available Yokenella regensburgei es un bacilo Gram negativo de la familia Enterobacteriaceae, que puede encontrarse en agua de pozos, alimentos y en el tubo digestivo de insectos y reptiles. Aunque se ha aislado de muestras provenientes de seres humanos, pocas veces se ha reportado como causante de infección y, en tales casos, especialmente en pacientes inmunosuprimidos. Se presenta aquí el primer caso de osteomielitis secundaria a una infección por Y. regensburgei en una paciente inmunocompetente después de un procedimiento quirúrgico.

  13. Fat Grams: How to Track Your Dietary Fat

    Science.gov (United States)

    ... I eat each day, should I focus on grams, calories or percentages? Answers from Katherine Zeratsky, R. ... want to use just one method, then tracking grams is probably the easiest. The American Heart Association ...

  14. Mars-GRAM 2010: Improving the Precision of Mars-GRAM

    Science.gov (United States)

    Justh, H. L.; Justus, C. G.; Ramey, H. S.

    2011-01-01

    It has been discovered during the Mars Science Laboratory (MSL) site selection process that the Mars Global Reference Atmospheric Model (Mars-GRAM) when used for sensitivity studies for Thermal Emission Spectrometer (TES) MapYear=0 and large optical depth values, such as tau=3, is less than realistic. Mars-GRAM's perturbation modeling capability is commonly used, in a Monte-Carlo mode, to perform high fidelity engineering end-to-end simulations for entry, descent, and landing (EDL). Mars-GRAM 2005 has been validated against Radio Science data, and both nadir and limb data from TES. Traditional Mars-GRAM options for representing the mean atmosphere along entry corridors include: (1) TES mapping year 0, with user-controlled dust optical depth and Mars-GRAM data interpolated from NASA Ames Mars General Circulation Model (MGCM) results driven by selected values of globally-uniform dust optical depth, or (2) TES mapping years 1 and 2, with Mars-GRAM data coming from MGCM results driven by observed TES dust optical depth. From the surface to 80 km altitude, Mars-GRAM is based on NASA Ames MGCM. Above 80 km, Mars-GRAM is based on the University of Michigan Mars Thermospheric General Circulation Model (MTGCM). MGCM results that were used for Mars-GRAM with MapYear=0 were from a MGCM run with a fixed value of tau=3 for the entire year at all locations. This choice of data has led to discrepancies that have become apparent during recent sensitivity studies for MapYear=0 and large optical depths. Unrealistic energy absorption by time-invariant atmospheric dust leads to an unrealistic thermal energy balance on the polar caps. The outcome is an inaccurate cycle of condensation/sublimation of the polar caps and, as a consequence, an inaccurate cycle of total atmospheric mass and global-average surface pressure. Under an assumption of unchanged temperature profile and hydrostatic equilibrium, a given percentage change in surface pressure would produce a corresponding percentage

  15. Prognostic factors and monomicrobial necrotizing fasciitis: gram-positive versus gram-negative pathogens

    Directory of Open Access Journals (Sweden)

    Hsu Wei-Hsiu

    2011-01-01

    Full Text Available Abstract Background Monomicrobial necrotizing fasciitis is rapidly progressive and life-threatening. This study was undertaken to ascertain whether the clinical presentation and outcome for patients with this disease differ for those infected with a gram-positive as compared to gram-negative pathogen. Methods Forty-six patients with monomicrobial necrotizing fasciitis were examined retrospectively from November 2002 to January 2008. All patients received adequate broad-spectrum antibiotic therapy, aggressive resuscitation, prompt radical debridement and adjuvant hyperbaric oxygen therapy. Eleven patients were infected with a gram-positive pathogen (Group 1 and 35 patients with a gram-negative pathogen (Group 2. Results Group 2 was characterized by a higher incidence of hemorrhagic bullae and septic shock, higher APACHE II scores at 24 h post-admission, a higher rate of thrombocytopenia, and a higher prevalence of chronic liver dysfunction. Gouty arthritis was more prevalent in Group 1. For non-survivors, the incidences of chronic liver dysfunction, chronic renal failure and thrombocytopenia were higher in comparison with those for survivors. Lower level of serum albumin was also demonstrated in the non-survivors as compared to those in survivors. Conclusions Pre-existing chronic liver dysfunction, chronic renal failure, thrombocytopenia and hypoalbuminemia, and post-operative dependence on mechanical ventilation represent poor prognostic factors in monomicrobial necrotizing fasciitis. Patients with gram-negative monobacterial necrotizing fasciitis present with more fulminant sepsis.

  16. Quorum sensing in gram-negative bacteria

    DEFF Research Database (Denmark)

    Wu, H.; Song, Z.J.; Høiby, N.

    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...

  17. Expressão de C-KIT como fator prognóstico para pacientes com câncer de mama triplo-negativos

    Directory of Open Access Journals (Sweden)

    Alexandre Ricardo Abdel Fattah Martini

    2014-10-01

    Full Text Available Introdução: O câncer de mama é o segundo tipo de câncer mais frequente do mundo, só perdendo para o câncer de pulmão. O mau prognóstico do câncer de mama está muito associado aos subtipos moleculares que ele apresenta. Os tumores triplo-negativos, são uma classe muito peculiar, por serem de um pior prognóstico e não apresentarem drogas específicas para tratamento. Outro receptor estudado atualmente é o c-KIT, um receptor de membrana tipo tirosina-kinase. Atualmente, estuda-se a expressão do c-KIT como um fator independente de pior prognóstico nos tumores de mama, o que justifica as pesquisas sobre a prevalência de sua expressão, que confirmem esse pior prognóstico. Fármacos que inibidores de tirosina-kinase, relevam a importância dessa relação para futuros tratamentos. Metodologia: é uma análise imunohistoquímica para procura da expressão de c-KIT em biópsias de triplo-negativo e, concomitantemente, avaliação de prontuários desses pacientes em busca de piores prognósticos da doença. Resultados: Foram analisados 9.975 registros entre 2011 e 2012, encontrou-se uma prevalência de triplo-negativos de 15,8%. Observamos a expressão de c-kit em 33% das amostras, sendo os maiores graus de expressão associados aos maiores estádios da doença. Conclusão: Assim como o ki-67, vimos que os maiores níveis de expressão esteve presente em altos graus de estadiamento. A expressão dos receptores pode ser utilizada como marcador de prognóstico.

  18. Rapid method for the differentiation of gram-positive and gram-negative bacteria on membrane filters.

    OpenAIRE

    Romero, S; Schell, R F; Pennell, D R

    1988-01-01

    Microfiltration has become a popular procedure for the concentration and enumeration of bacteria. We developed a rapid and sensitive method for the differentiation of gram-positive and gram-negative bacteria, utilizing a polycarbonate membrane filter, crystal violet, iodine, 95% ethanol, and 6% carbol fuchsin, that can be completed in 60 to 90 s. Gram reactions of 49 species belonging to 30 genera of bacteria were correctly determined by the filter-Gram stain. The sensitivities of the filter-...

  19. Conjugation in Gram-Positive Bacteria.

    Science.gov (United States)

    Goessweiner-Mohr, Nikolaus; Arends, Karsten; Keller, Walter; Grohmann, Elisabeth

    2014-08-01

    Conjugative transfer is the most important means of spreading antibiotic resistance and virulence factors among bacteria. The key vehicles of this horizontal gene transfer are a group of mobile genetic elements, termed conjugative plasmids. Conjugative plasmids contain as minimum instrumentation an origin of transfer (oriT), DNA-processing factors (a relaxase and accessory proteins), as well as proteins that constitute the trans-envelope transport channel, the so-called mating pair formation (Mpf) proteins. All these protein factors are encoded by one or more transfer (tra) operons that together form the DNA transport machinery, the Gram-positive type IV secretion system. However, multicellular Gram-positive bacteria belonging to the streptomycetes appear to have evolved another mechanism for conjugative plasmid spread reminiscent of the machinery involved in bacterial cell division and sporulation, which transports double-stranded DNA from donor to recipient cells. Here, we focus on the protein key players involved in the plasmid spread through the two different modes and present a new secondary structure homology-based classification system for type IV secretion protein families. Moreover, we discuss the relevance of conjugative plasmid transfer in the environment and summarize novel techniques to visualize and quantify conjugative transfer in situ.

  20. Textualidad y gramática argumentativa

    Directory of Open Access Journals (Sweden)

    RAÚL FIRACATIVE-RUIZ

    2014-01-01

    Full Text Available La argumentación es un modo de organizar el discurso, cuya orientación se da para lograr el convencimiento del otro. El presente artículo acoge este precepto para abordar la propuesta argumentativa del autor italiano Vincenzo Lo Cascio desde la noción de textualidad . Gramática argumentativa es el nombre dado a esta apuesta teórica y surge de las ideas de la Nueva Retórica de Perelman. Lo Cascio propone la existencia de categorías sintácticas finitas, denominadas reglas categoriales e indicadores de fuerza , las cuales permiten orientar la información de los enunciados y analizar multiplicidad de discursos; por ello, es una teoría que sigue la línea de la sintaxis generativa de Noam Chomsky. El artículo plantea la necesidad de reconocer, desde la Gramática argumentativa, el potencial enunciativo de la palabra en situaciones comunicativas cotidianas, donde es preciso que los enunciadores sean conscientes del uso que hacen de la palabra.

  1. Correlação anátomo-clínica: granulomatose sistêmica por talco em drogadicto hiv negativo

    Directory of Open Access Journals (Sweden)

    Cunha D.F. da

    1999-01-01

    Full Text Available É descrita a correlação anatomopatológica de um paciente usuário de drogas injetáveis com talcose sistêmica acometendo pulmões, pleuras, fígado, baço e linfonodos e que desenvolveu hipertensão arterial pulmonar e cor pulmonale. Destaca-se o fato de que apesar do uso crônico de drogas injetáveis e outros comportamentos de alto risco para infecção pelo retrovírus, o paciente era HIV negativo, não apresentava linfocitopenia, nem alterações histopatológicas compatíveis com AIDS à necropsia.

  2. Estudio de la actividad antimicrobiana del fango termal de Copahue (Neuquén, Argentina

    Directory of Open Access Journals (Sweden)

    Juan A. Basualdo

    2011-01-01

    Full Text Available Se investigó la actividad antimicrobiana del fango termal (Complejo Termal Copahue, Argentina sobre microorganismos de la microbiota autóctona del hombre, agentes infecciosos de la comunidad, hospitalarios y cepas AT CC. Las cepas correspondieron a cocos Gram positivos, bacilos Gram negativos, levaduras y cepas AT CC. El fango se obtuvo de la Laguna Sulfurosa. La actividad inhibitoria se demostró utilizando fase líquida (FL mediante la prueba de difusión en agar y por estudios de cinética bactericida. Con la primera se observó halo inhibitorio frente a Staphylococcus aureus y Cándida albicans, no visualizándose inhibición para el resto de los microorganismos. El estudio dinámico a través del tiempo sobre S. aureus, Enterococcus faecalis, Staphylococcus epidermis y C. albicans demostró acción inhibitoria antes de las 6 hs de incubación, mientras que no se observó inhibición frente a los bacilos Gram negativos. Es el primer trabajo que demuestra la actividad antimicrobiana de la FL sobre las cepas ensayadas.

  3. Techniques for controlling variability in gram staining of obligate anaerobes.

    Science.gov (United States)

    Johnson, M J; Thatcher, E; Cox, M E

    1995-01-01

    Identification of anaerobes recovered from clinical samples is complicated by the fact that certain gram-positive anaerobes routinely stain gram negative; Peptostreptococcus asaccharolyticus, Eubacterium plautii, Clostridium ramosum, Clostridium symbiosum, and Clostridium clostridiiforme are among the nonconformists with regard to conventional Gram-staining procedures. Accurate Gram staining of American Type Culture Collection strains of these anaerobic bacteria is possible by implementing fixing and staining techniques within a gloveless anaerobic chamber. Under anaerobic conditions, gram-positive staining occurred in all test organisms with "quick" fixing techniques with both absolute methanol and formalin. The results support the hypothesis that, when anaerobic bacteria are exposed to oxygen, a breakdown of the physical integrity of the cell wall occurs, introducing Gram stain variability in gram-positive anaerobes. PMID:7538512

  4. [Predictive factors for hospital infections caused by Gram-positive and Gram-negative organisms].

    Science.gov (United States)

    Domínguez-Castellano, A; Cerro, R; Bueno, C; Bringas, M J; Balonga, B; Royo, J L

    1995-12-01

    Knowing the bacterian map and clinical profile of nosocomial infections (NI) in Spain may aid the better planning of empiric antimicrobian treatment. A prospective incidence study carried out over 9 months was performed. Data collection out with the use of an EPINE project file. The chi square test and comparison of independent sample percentages were used for statistical analysis. During the study period 156 cases of NI (rate (5.5%) were detected: 65 patients with gram-negative bacilli infection (GNB), 34 by gram-positive cocci (GPC), 20 with mixed infection and 13 by Candida. The most frequent localization was urinary infection (63%) followed by surgical wound infection, pressure ulcers and respiratory infection. Of the 203 isolations, 57% corresponded to GNB, with E. coli being the most frequent microorganism. Staphylococcus aureus was the GPC most often found (95% methycilline sensitive). The profile of a patient with nosocomial infection in a hospital such as that in which the autors work would be as follows: if the patient were admitted in the department of internal medicine, was dementia or coma, denutrition, urinary catheter or neurologic disease and has NI (overall urinary infection) the infection would most likely be a caused by a gram-negative microorganism. If the patient has an i.v. line or is in a surgical ward, or has deep surgical wound infection the microorganism isolated would most likely be gram-positive.

  5. Medicalização dos desvios de comportamento na infância: aspectos positivos e negativos Medicalización de los desvíos de comportamiento en la infancia: aspectos positivos y negativos Medicalization of deviant behavior in children: positive and negative features

    Directory of Open Access Journals (Sweden)

    Fabíola Stolf Brzozowski

    2013-01-01

    Full Text Available A medicalização dos comportamentos desviantes na infância é apresentada como uma estratégia eficaz para lidar com crianças que apresentam algum tipo de dificuldade, sem que, no entanto, as dificuldades desse processo sejam claramente expostas. O processo de medicalização, porém, é complexo e apresenta muitos resultados negativos. Dentro desse contexto, nosso objetivo é refletir sobre essas dificuldades. Primeiramente, apresentamos como se dá a relação entre medicalização e infâcia. Em seguida, discutimos alguns aspectos considerados positivos e negativos da medicalização. Para finalizar, consideramos que enquadrar uma criança em um diagnóstico psiquiátrico apresenta sérias consequências indesejáveis, e acaba sendo mais útil para a sociedade e para o entorno da criança do que para a própria criança.La medicalización de los comportamientos desviantes en la infancia es presentada como una estrategia eficaz para manejar niños que presentan algún tipo de dificultad, sin que, sin embargo, las dificultades de ese proceso sean claramente expuestas. El proceso de medicalización, sin embargo, es complejo y presenta muchos resultados negativos. En ese contexto, nuestro objetivo es reflexionar sobre esas dificultades. Primero, presentamos como se da la relación entre medicalización e infancia. Enseguida, discutimos algunos aspectos considerados positivos y negativos de la medicalización. Para finalizar, consideramos que encuadrar un niño en un diagnóstico psiquiátrico presenta serias consecuencias indeseables, y acaba siendo más útil para la sociedad y para el entorno del niño de lo que para el propio niño.The medicalization of deviant behaviors during childhood is usually presented as an effective strategy to deal with troublesome children, but the problems associated with medicalization are not frequently exposed. Even so, the process of medicalization is complex and may present many negative results. In this

  6. Materiales basados en aluminosilicatos de litio con coeficiente de expansión térmica negativos en un amplio intervalo de temperatura, procedimiento de preparación y uso

    OpenAIRE

    Torrecillas, Ramón; Fernández, Adolfo; García Moreno, Olga

    2008-01-01

    Materiales basados en aluminosilicatos de litio con coeficiente de expansión térmica negativos en un amplio intervalo de temperatura, procedimiento de preparación y uso. Nuevo procedimiento para la obtención de materiales cerámicos basados en aluminosilicatos de litio (LAS) con coeficiente de expansión térmica próximos a cero y negativos en el intervalo de temperatura (-150ºC a 450ºC). Estos materiales tienen su aplicación en la fabricación de componentes que requie...

  7. Evaluation of post-antibiotic effect in Gram-negative and Gram-positive bacteria

    Directory of Open Access Journals (Sweden)

    Elisa Tavella

    2008-03-01

    Full Text Available Although the postantibiotic effect (PAE is a well recognized phenomenon, the mechanism by which it is induced has not fully elucidated yet. It has been suggested that PAE is the time required by bacteria to synthesize proteins or mRNA characterized by a short half-life that are consumed during antibiotic treatment.This phenomenon is widely studied on Gram-positive cocci and Gram-negative rods, while information about Gram-positive rods and Gram-negative cocci are scanty.To gain new insights on the PAE, this study was addressed to evaluated the time required by Moraxella catarrhalis and Lactobacillus planctarum to resume their physiological growth rate after exposure to various antibiotics. Methods PAE was estimated in accordance with the method of Craig and Gudmundsson using the following drugs: penicillin, piperacillin-tazobactam, cefalotin, ceftazidime, imipenem, ciprofloxacin, gentamycin and azithromycin. Log-phase bacteria were exposed to drug at a concentration corresponding to 4 times the MIC value for 1h.The drug was inactivated by 1:1000 dilution. Bacterial counts were determined at time zero, immediately after drug dilution, and at each hour after removal for 6 - 7h by a pour-plate technique. The PAE was defined as the difference in time required by test and control cultures to increase by 1 log in CFU number. Results All drugs tested induced a PAE on the strains studied. M. catarrhalis registered PAE values ranging between 0,5 (gentamycin and 2 (ceftazidime, imipenem and azithromycin.With respect to L. plantarum a PAE between 0,8 (cefalotin and 3 hours (ciprofloxacin were detected. Conclusion. These findings demonstrated that all the drugs tested were able to induce a PAE on the strains tested.This observation differs from that observed on Gram-negative rods characterised by negative PAE values induced by penicillins and cephalosporins.This results might reflect the different target of these compounds on these Gram-positive rods or the

  8. The Gram stain after more than a century.

    Science.gov (United States)

    Popescu, A; Doyle, R J

    1996-05-01

    The Gram stain, the most important stain in microbiology, was described more than a century ago. Only within the past decade, however, has an understanding of its mechanism emerged. It now seems clear that the cell wall of Gram-positive microorganisms is responsible for retention of a crystal violet:iodine complex. In Gram-negative cells, the staining procedures damage the cell surface resulting in loss of dye complexes. Gram-positive microorganisms require a relatively thick cell wall, irrespective of composition, to retain the dye. Therefore, Gram-stainability is a function of the cell wall and is not related to chemistry of cell constituents. This review provides a chronology of the Gram stain and discusses its recently discovered mechanism.

  9. Prediction of lipoprotein signal peptides in Gram-negative bacteria

    DEFF Research Database (Denmark)

    Juncker, Agnieszka; Willenbrock, Hanni; Von Heijne, G.

    2003-01-01

    A method to predict lipoprotein signal peptides in Gram-negative Eubacteria, LipoP, has been developed. The hidden Markov model (HMM) was able to distinguish between lipoproteins (SPaseII-cleaved proteins), SPaseI-cleaved proteins, cytoplasmic proteins, and transmembrane proteins. This predictor...... was able to predict 96.8% of the lipoproteins correctly with only 0.3% false positives in a set of SPaseI-cleaved, cytoplasmic, and transmembrane proteins. The results obtained were significantly better than those of previously developed methods. Even though Gram-positive lipoprotein signal peptides differ...... from Gram-negatives, the HMM was able to identify 92.9% of the lipoproteins included in a Gram-positive test set. A genome search was carried out for 12 Gram-negative genomes and one Gram-positive genome. The results for Escherichia coli K12 were compared with new experimental data, and the predictions...

  10. Sonodynamic Excitation of Rose Bengal for Eradication of Gram-Positive and Gram-Negative Bacteria

    Directory of Open Access Journals (Sweden)

    Faina Nakonechny

    2013-01-01

    Full Text Available Photodynamic antimicrobial chemotherapy based on photosensitizers activated by illumination is limited by poor penetration of visible light through skin and tissues. In order to overcome this problem, Rose Bengal was excited in the dark by 28 kHz ultrasound and was applied for inactivation of bacteria. It is demonstrated, for the first time, that the sonodynamic technique is effective for eradication of Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. The net sonodynamic effect was calculated as a 3-4 log10 reduction in bacteria concentration, depending on the cell and the Rose Bengal concentration and the treatment time. Sonodynamic treatment may become a novel and effective form of antimicrobial therapy and can be used for low-temperature sterilization of medical instruments and surgical accessories.

  11. Diagnosing periprosthetic infection: false-positive intraoperative Gram stains.

    Science.gov (United States)

    Oethinger, Margret; Warner, Debra K; Schindler, Susan A; Kobayashi, Hideo; Bauer, Thomas W

    2011-04-01

    Intraoperative Gram stains have a reported low sensitivity but high specificity when used to help diagnose periprosthetic infections. In early 2008, we recognized an unexpectedly high frequency of apparent false-positive Gram stains from revision arthroplasties. The purpose of this report is to describe the cause of these false-positive test results. We calculated the sensitivity and specificity of all intraoperative Gram stains submitted from revision arthroplasty cases during a 3-month interval using microbiologic cultures of the same samples as the gold standard. Methods of specimen harvesting, handling, transport, distribution, specimen processing including tissue grinding/macerating, Gram staining, and interpretation were studied. After a test modification, results of specimens were prospectively collected for a second 3-month interval, and the sensitivity and specificity of intraoperative Gram stains were calculated. The retrospective review of 269 Gram stains submitted from revision arthroplasties indicated historic sensitivity and specificity values of 23% and 92%, respectively. Systematic analysis of all steps of the procedure identified Gram-stained but nonviable bacteria in commercial broth reagents used as diluents for maceration of periprosthetic membranes before Gram staining and culture. Polymerase chain reaction and sequencing showed mixed bacterial DNA. Evaluation of 390 specimens after initiating standardized Millipore filtering of diluent fluid revealed a reduced number of positive Gram stains, yielding 9% sensitivity and 99% specificity. Clusters of false-positive Gram stains have been reported in other clinical conditions. They are apparently rare related to diagnosing periprosthetic infections but have severe consequences if used to guide treatment. Even occasional false-positive Gram stains should prompt review of laboratory methods. Our observations implicate dead bacteria in microbiologic reagents as potential sources of false-positive Gram

  12. Raman Spectroscopy of Xylitol Uptake and Metabolism in Gram-Positive and Gram-Negative Bacteria▿

    Science.gov (United States)

    Palchaudhuri, Sunil; Rehse, Steven J.; Hamasha, Khozima; Syed, Talha; Kurtovic, Eldar; Kurtovic, Emir; Stenger, James

    2011-01-01

    Visible-wavelength Raman spectroscopy was used to investigate the uptake and metabolism of the five-carbon sugar alcohol xylitol by Gram-positive viridans group streptococcus and the two extensively used strains of Gram-negative Escherichia coli, E. coli C and E. coli K-12. E. coli C, but not E. coli K-12, contains a complete xylitol operon, and the viridans group streptococcus contains an incomplete xylitol operon used to metabolize the xylitol. Raman spectra from xylitol-exposed viridans group streptococcus exhibited significant changes that persisted even in progeny grown from the xylitol-exposed mother cells in a xylitol-free medium for 24 h. This behavior was not observed in the E. coli K-12. In both viridans group streptococcus and the E. coli C derivative HF4714, the metabolic intermediates are stably formed to create an anomaly in bacterial normal survival. The uptake of xylitol by Gram-positive and Gram-negative pathogens occurs even in the presence of other high-calorie sugars, and its stable integration within the bacterial cell wall may discontinue bacterial multiplication. This could be a contributing factor for the known efficacy of xylitol when taken as a prophylactic measure to prevent or reduce occurrences of persistent infection. Specifically, these bacteria are causative agents for several important diseases of children such as pneumonia, otitis media, meningitis, and dental caries. If properly explored, such an inexpensive and harmless sugar-alcohol, alone or used in conjunction with fluoride, would pave the way to an alternative preventive therapy for these childhood diseases when the causative pathogens have become resistant to modern medicines such as antibiotics and vaccine immunotherapy. PMID:21037297

  13. Gram-Charlier Processes and Applications to Option Pricing

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Chateau

    2017-01-01

    Full Text Available A Gram-Charlier distribution has a density that is a polynomial times a normal density. For option pricing this retains the tractability of the normal distribution while allowing nonzero skewness and excess kurtosis. Properties of the Gram-Charlier distributions are derived, leading to the definition of a process with independent Gram-Charlier increments, as well as formulas for option prices and their sensitivities. A procedure for simulating Gram-Charlier distributions and processes is given. Numerical illustrations show the effect of skewness and kurtosis on option prices.

  14. Gram-positive bacteria persisting in the food production environment

    DEFF Research Database (Denmark)

    Knøchel, Susanne; Harmsen, Morten; Knudsen, Bettina

    2008-01-01

    Many gram-positive bacteria are able to form aggregates or biofilms and resist external stress factors and some gram-positive pathogenic bacteria such as Listeria monocytogenes and Bacillus cereus may persist in the food production environment for extended periods. Most research has focussed...... on the gram-negative bacteria and, in general, less is known abourt the gram poritives. At present much conflicting evidence has been presented perhaps because so many internal and external factors influence the ability to adhere. Some of the present knowledge of biofilm or aggregation forming properties...

  15. Contribuição do contraste negativo na artrografia tomográfica do joelho normal de cães

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    M.F. Almeida

    2011-04-01

    Full Text Available A ruptura do ligamento cruzado cranial é uma das causas mais comuns de claudicação do membro pélvico de cães. A radiografia e a ultrassonografia são métodos de diagnóstico frequentemente utilizados na rotina clínica de pequenos animais, porém a tomografia computadorizada é uma modalidade de imagem ainda pouco estudada para avaliar a articulação do joelho de cães. O presente trabalho teve por objetivo avaliar a contribuição do contraste negativo na artrografia tomográfica do joelho normal de cães, para visibilizar as estruturas intra-articulares e padronizar o uso desse contraste na articulação. Foram utilizados 24 membros pélvicos de cães de raças variadas, selecionados pela ausência de histórico de doença articular prévia do joelho e por apresentarem exames radiográficos, ultrassonográficos e macroscópicos normais. O experimento foi delineado em dois grupos, sendo o grupo I constituído de animais com peso até 20 kg e grupo II acima de 20 kg. Foram feitos cortes tomográficos com o membro flexionado e estendido. A quantidade média de ar empregada para a distensão da cápsula articular foi de 49 ml para o Grupo I e de 81 ml para o Grupo II. Utilizou-se um tubo de látex na porção distal à articulação do joelho para reduzir o escape de ar pelo tendão extensor digital profundo, que possui comunicação intra-articular. Foi possível visibilizar pela imagem tomográfica, em todas as articulações, as seguintes estruturas: ligamento cruzado cranial e caudal, meniscos medial e lateral, ligamento patelar, ligamentos colaterais e cápsula articular. Desta forma, o contraste negativo se mostrou uma alternativa eficaz para auxiliar a identificação das estruturas anatômicas do joelho na artrografia tomográfica.

  16. Laboratory detection methods for methicillin resistance in coagulase negative Staphylococcus isolated from ophthalmic infections Métodos laboratoriais para a detecção da resistência à meticilina nos Staphylococcus coagulase negativos de infecções oculares

    Directory of Open Access Journals (Sweden)

    Adália Dias Dourado Oliveira

    2007-08-01

    Full Text Available PURPOSE: To evaluate different methods of oxacillin susceptibility testing of ocular isolates, considering polymerase chain reaction (PCR as the 'gold standard', and to compare the in vitro susceptibility to oxacillin with that of other antimicrobials used in ophthalmologic practice. METHODS: The Vitek gram-positive identification card was used to identify ocular coagulase negative Staphylococcus species. The presence of the mecA gene was determined by the polymerase chain reaction assay with a combination of two primer sets (mecA and 16S rRNA in a single region. Results were analyzed and compared with other oxacillin susceptibility methods: PBP2a detection by rapid slide latex agglutination test (SLA; oxacillin E-test; the Vitek automated gram-positive susceptibility card (GPS-105; the oxacillin salt agar screening test (OSAS at a concentration of 6.0, 1.0 and 0.75 µg oxacillin per ml and the cefoxitin disk diffusion test (CDD. Automated susceptibility was also determined to other antimicrobial agents (fluoroquinolones, penicillin G, amoxicillin-ampicillin, cefazolin, ampicillin-sulbactam, erythromycin, clindamycin, gentamicin, tetracycline, trimethoprim-sulfamethoxazole, vancomycin and rifampin. RESULTS: Of the 69 CoNS isolates tested, 71% were mecA-positive and 29% mecA-negative. All methods tested had a statistically significant agreement with polymerase chain reaction. There was a tendency of positive polymerase chain reaction predomination among the S. epidermidis isolates in comparison to non-epidermidis isolates, although this was not statistically significant (78.3% vs. 56.5%; chi2= 2.54; P= 0.11. The oxacillin salt agar screening test (0.75 µg oxacillin/ml showed the best performance, with 100% sensitivity and negative predictive value; 95% specificity and 98% positive predictive value. Using the E-test, the mecA-positive isolates were statistically significantly more resistant to ciprofloxacin, ofloxacin, gatifloxacin and

  17. Antimicrobial Activity of Carbon Nanoparticles Isolated from Natural Sources against Pathogenic Gram-Negative and Gram-Positive Bacteria

    Directory of Open Access Journals (Sweden)

    Sheena Varghese

    2013-01-01

    Full Text Available This paper describes the isolation of carbon nanoparticles (CNPs from kitchen soot, characterization of the CNPs by UV/visible spectroscopy, SEM and XRD, and their antimicrobial action. The antibacterial activity of the isolated carbon nanoparticles was tested against various pathogenic bacterial strains such as Gram-negative Proteus refrigere and Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus and Streptococcus haemolyticus. The inhibition zones were measured, and it was found that the carbon nanoparticles isolated from natural sources are active against these Gram-negative and Gram-positive bacterial strains.

  18. Neoconstitucionalismo negativo y neoconstitucionalismo positivo

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    Giovanni Battista Ratti

    2015-09-01

    Full Text Available La expresión “neoconstitucionalismo” es sumamente ambigua: la cultura contemporánea la usa para denotar cosas tan heterogéneas como una forma de estado, una política de activismo judicial, una reconstrucción teórica de los sistemas jurídicos contemporáneos, una metodología jurídica y una adhesión ideológica al derecho. Este trabajo se centra en los aspectos de política jurisprudencial, de teoría del derecho y de metodología jurídica, enfatizando dos posibles perspectivas del neoconstitucionalismo: una negativa que delinea dicha multifacética concepción del derecho como un conjunto de oposiciones a las tesis defendidas por las concepciones dominantes, y otra positiva que pretende haber identificado una serie de “nuevos descubrimientos” en los sistemas jurídicos contemporáneos. En esta versión positiva se examinan ocho tesis: (1 el derecho de los estados constitucionales es una combinación de reglas y principios, (2 reglas y principios son aptos para constituir un conjunto sistematico de normas, (3 las constituciones contemporáneas incorporan valores morales, de manera que habrían creado una conexión relevante entre derecho y moral, (4 tal incorporación implica un deber de interpretar las disposiciones constitucionales mediante una lectura moral, (5 toda norma jurídica es derrotable, (6 algunos estándares jurídicos requieren de un razonamiento ponderativo o de balance, opuesto al tradicional razonamiento subsutivo, (7 interpretando holísticamente las disposiciones jurídicas, los jueces pueden llegar a decidir cualquier controversia, y,  (8 las normas jurídicas no pueden tener cualquier contenido, porque su contenido es determinado en última instancia por juicios morales. El trabajo termina ilustrando aciertos y equivocaciones de cada versión del neoconstitucionalismo.

  19. The gram stain smear: A screening test for genital mycoplasmas ...

    African Journals Online (AJOL)

    Result of 168 vaginal specimens from women examined for genital mycoplasmas showed that more of these organisms were isolated from specimens whose Gram stain smears were devoid of Gram positive bacilli (GPB) (43%) as against those whose smears contain GPB (22.1%). This result was found to be statistically ...

  20. Methods for targetted mutagenesis in gram-positive bacteria

    Science.gov (United States)

    Yang, Yunfeng

    2014-05-27

    The present invention provides a method of targeted mutagenesis in Gram-positive bacteria. In particular, the present invention provides a method that effectively integrates a suicide integrative vector into a target gene in the chromosome of a Gram-positive bacterium, resulting in inactivation of the target gene.

  1. In vitro susceptibility of gram-negative bacterial isolates to ...

    African Journals Online (AJOL)

    In vitro susceptibility of gram-negative bacterial isolates to chlorhexidine gluconate. Y Mengistu, W Erge, B Bellete. Abstract. Objective: To investigate the susceptibility of clinical isolates of gram-negative bacteria to chlorhexidine gluconate. Design: Prospective laboratory study. Setting: Tikur Anbessa Hospital, Addis Ababa, ...

  2. Volumetric and viscometric behaviour of soya bean and gram ...

    African Journals Online (AJOL)

    Volumetric and viscometric behaviour of soya bean and gram proteins in aqueous methotrexate (anticancer drug) solution at 298.15 to 308.15K. ... and viscosities (h) for 0.00005 to 0.0004 kg.mol-1 (50 to 400 mmol kg-1) aqueous methotrexate (MTX), gram (Gp) and soya bean (SBp) proteins, and similar compositions of Gp

  3. Gram-positive bacteria persisting in the food production environment

    DEFF Research Database (Denmark)

    Knøchel, Susanne; Harmsen, Morten; Knudsen, Bettina

    2008-01-01

    Many gram-positive bacteria are able to form aggregates or biofilms and resist external stress factors and some gram-positive pathogenic bacteria such as Listeria monocytogenes and Bacillus cereus may persist in the food production environment for extended periods. Most research has focussed...

  4. Diesel degradation and biosurfactant production by Gram-positive ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-02

    Nov 2, 2009 ... This study clearly demonstrates that Gram-positive biosurfactant producing bacteria are effective in diesel degradation. Key words: Diesel, biodegradation, Paenibacillus sp., Stenotrophomonas sp., Gram-positive bacteria, biosurfactant. INTRODUCTION. Hydrocarbons such as diesel fuel, crude oil and.

  5. Genetic diversity in green gram accessions as revealed by STMS ...

    African Journals Online (AJOL)

    Molecular characterization of green gram (Vigna radiata (L.) Wilczek) germplasm is essential for scientific assessment of variability and diversity for its better utilization in breeding programs. In this study, 120 accessions of green gram were analysed for 27 Sequence Tagged Microsatellites (STMS) loci. For data analysis ...

  6. Antimicrobial resistance of gram-negative aerobic bacteria isolates ...

    African Journals Online (AJOL)

    The increasing incidence of antimicrobial resistance in pathogenic and commensal Gram-negative bacteria from dogs has continued to raise concerns in veterinary small animal practice and public health. In this study, antimicrobial resistance was investigated in Gram-negative aerobic bacteria isolated from the faeces of ...

  7. Decreased mortality associated with prompt Gram staining of blood cultures.

    Science.gov (United States)

    Barenfanger, Joan; Graham, Donald R; Kolluri, Lavanya; Sangwan, Gaurav; Lawhorn, Jerry; Drake, Cheryl A; Verhulst, Steven J; Peterson, Ryan; Moja, Lauren B; Ertmoed, Matthew M; Moja, Ashley B; Shevlin, Douglas W; Vautrain, Robert; Callahan, Charles D

    2008-12-01

    Gram stains of positive blood cultures are the most important factor influencing appropriate therapy. The sooner appropriate therapy is initiated, the better. Therefore, it is reasonable to expect that the sooner Gram stains are performed, the better. To determine the value of timely Gram stains and whether improvement in Gram stain turnaround time (TAT) is feasible, we compared data for matched pairs of patients with cultures processed promptly ( or =1 hour TAT) and then monitored TAT by control charting.In 99 matched pairs, average difference in time to detection of positive blood cultures within a pair of patients was less than 0.1 hour. For the less than 1 hour TAT group, the average TAT and crude mortality were 0.1 hour and 10.1%, respectively; for the 1 hour or longer TAT group, they were 3.3 hours and 19.2%, respectively (P Gram stains.

  8. Gender differences in negative mood states in secondary school students: health survey in Catalonia (Spain Diferencias en los estados de ánimo negativo en estudiantes de secundaria según sexo: encuesta de salud en Cataluña

    Directory of Open Access Journals (Sweden)

    Mónica Monteagudo

    2013-02-01

    Full Text Available Objective: To determine the prevalence of negative mood states in adolescents according to gender, to analyze variability among schools, and to evaluate the associated factors. Methods: A cross-sectional study with a cluster design was carried out. We administered the High-school students health survey to a sample of 9,340 students (aged 14-16 years in the third and fourth year of Compulsory Secondary Education in Catalonia, Spain, during the 2005-6 academic year. The main outcome measure was evidence of a negative mood state. A multilevel logistic regression model stratified by gender was used to identify the factors associated with negative mood states and to determine variability among distinct schools. Results: Approximately 19% of adolescents reported evidence of a negative mood state, with a higher prevalence in girls (25%. The most significant factors associated with negative mood states were "use of tranquilizers" and "having eating disorders" in girls and "not exercising" and "poor self-perception of health status" in boys. In both genders, variability was found among schools in the prevalence of negative mood states (girls: variance = 0.078; p Objetivos: Determinar la prevalencia del estado de ánimo negativo entre alumnos adolescentes según sexo, analizar la variabilidad entre escuelas y evaluar los factores asociados. Métodos: Estudio transversal basado en un muestreo por conglomerados bietápico. Administramos una encuesta de salud a 9340 estudiantes de tercero y cuarto curso de Educación Secundaria Obligatoria de 14 a 16 años de edad, en Cataluña, durante el curso escolar 2005-06. La variable principal fue el estado de ánimo negativo. Se usó un modelo de regresión logística multinivel estratificado por sexo para identificar los factores asociados al estado de ánimo negativo y determinar la variabilidad entre las diferentes escuelas. Resultados: Aproximadamente el 19% de los adolescentes refirieron un estado de

  9. Bio sorption of some Rare Earth Elements and Yttrium by Gram Positive and Gram Negative Bacteria

    International Nuclear Information System (INIS)

    Ibrahim, H.A.

    2012-01-01

    The separate bio sorption of the REEs La, Sm, Eu and Dy together with yttrium upon the Gram positive bacteria Bacillus subtilis (B.subtilis) and Bacillus Licheniformis (B. Licheniformis),the Gram negative bacterium Escherichia coli (E. coli ) and Saccharomyces cervisiae (Yeast) was studied. The revelant factors of ph 1-6, contact time (30-180 min), the initial rare earth concentration (50-200 mg/l) have been studied. The amount of the accumulated element was strongly affected by its concentration.In addition, bio sorptive fractionation of Y and the studied REEs from a solution containing a mixture of these elements was also studied. From the obtained data, it was found that Langmuir isotherm model for both B.licheniformis and E.coli gives a best fit for the studied elements over the working range of concentration (50-200 mg/I). Transmission electron microscopy exhibited accumulation throughout the bacterial cell with some granular deposits in both the cell periphery and cytoplasm

  10. Protein classification using modified n-grams and skip-grams.

    Science.gov (United States)

    Islam, S M Ashiqul; Heil, Benjamin J; Kearney, Christopher Michel; Baker, Erich J

    2017-12-22

    Classification by supervised machine learning greatly facilitates the annotation of protein characteristics from their primary sequence. However, the feature generation step in this process requires detailed knowledge of attributes used to classify the proteins. Lack of this knowledge risks the selection of irrelevant features, resulting in a faulty model. In this study, we introduce a supervised protein classification method with a novel means of automating the work-intensive feature generation step via a Natural Language Processing (NLP)-dependent model, using a modified combination of n-grams and skip-grams (m- NGSG). A meta-comparison of cross-validation accuracy with twelve training datasets from nine different published studies demonstrates a consistent increase in accuracy of m-NGSG when compared to contemporary classification and feature generation models. We expect this model to accelerate the classification of proteins from primary sequence data and increase the accessibility of protein characteristic prediction to a broader range of scientists. m-NGSG is freely available at Bitbucket: https://bitbucket.org/sm islam/mngsg/src A web server is available at watson.ecs.baylor.edu/ngsg. link to Supplement documents. Erich_Baker@baylor.edu. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  11. Validez de las escalas de afecto positivo y negativo (PANAS en niños (Validity Of The Positive And Negative Affect Schedule (PANAS In Children

    Directory of Open Access Journals (Sweden)

    Norma Ivonne González Arratia López Fuentes

    2015-06-01

    Full Text Available Resumen El presente estudio tiene como objetivo evaluar las propiedades psicométricas de las escalas PANAS (afecto positivo y afecto negativo, su validez convergente con una medida de resiliencia y fiabilidad en una muestra de 194 niños, de ambos sexos, entre 9 y 12 años edad, de la ciudad de Toluca, México. Del análisis factorial exploratorio con el método de componentes principales y rotación ortogonal, se comprueba la estructura bidimensional, que explica el 44.85 % de la varianza total y confiabilidad alfa de Cronbach alta, lo que sugiere características psicométricas similares a las de la versión original y se comprueba la validez convergente con resiliencia. Se concluye que la escala es pertinente para niños mexicanos, pero se requiere ampliar la muestra que permita el uso de técnicas confirmatorias. Abstract The present study aims to evaluate the psychometric properties of the Positive and Negative Affect Schedule (PANAS, its convergent validity with a measure of resilience and reliability in a sample of 194 children of both sexes, between 9 and 12 years old in Toluca city, Mexico. The exploratory factor analysis with the principal components method and orthogonal rotation,verifies the dimensional structure that explains 44.85 % of the total variance, and high Cronbach Alpha reliability, suggesting psychometric characteristics similar to those of the original version, and confirms the convergent validity with resilience. It is concluded that the scale is relevant to Mexican children, but there is a need to expand the sample to allow the use of confirmatory techniques.

  12. Comparing Medline citations using modified N-grams.

    Science.gov (United States)

    Nawab, Rao Muhammad Adeel; Stevenson, Mark; Clough, Paul

    2014-01-01

    We aim to identify duplicate pairs of Medline citations, particularly when the documents are not identical but contain similar information. Duplicate pairs of citations are identified by comparing word n-grams in pairs of documents. N-grams are modified using two approaches which take account of the fact that the document may have been altered. These are: (1) deletion, an item in the n-gram is removed; and (2) substitution, an item in the n-gram is substituted with a similar term obtained from the Unified Medical Language System Metathesaurus. N-grams are also weighted using a score derived from a language model. Evaluation is carried out using a set of 520 Medline citation pairs, including a set of 260 manually verified duplicate pairs obtained from the Deja Vu database. The approach accurately detects duplicate Medline document pairs with an F1 measure score of 0.99. Allowing for word deletions and substitution improves performance. The best results are obtained by combining scores for n-grams of length 1-5 words. Results show that the detection of duplicate Medline citations can be improved by modifying n-grams and that high performance can also be obtained using only unigrams (F1=0.959), particularly when allowing for substitutions of alternative phrases.

  13. Septicemia and meningitis Septicemia y meningitis neonatales. 1981-1986. una etiología cambiante?

    Directory of Open Access Journals (Sweden)

    Rafael J. Manotas Cabarcas

    1988-02-01

    Full Text Available

    We reviewed the 20 cases of neonatal septicemia diagnosed at HospItal Infantil, Medellin, Colombia, between 1981 and 1986. Eleven were premature babies; in 12 septicemia had an early onset. In 5 the Infective agent was Klebsiella spp. and in another 5 It was a gram negative bacillus different from either Klebsiella or. Escherichia coli. Seven patients died, of whom 6 had been infected with gram negative bacilli. In 5 septicemia was complicated with meningitis, 4 of which occurred In cases with early onset. Relative Risk for death due to septicemia was greater among patients undergoing surgical procedures to correct congenital malformations and In those suffering from perinatal hypoxia. The risk for development of meningitis was greater among patients with early onset septicemia. We conclude that a change is taking place In the etiology of neonatal sepsis In than gram negative bacilli, different from Escherichia coli are now predominant.

    Se hizo una revisión de los casos de septicemia y meningitis neo natales diagnosticados en el Hospital Infantil de Medellín entre 1981 y 1986; se detectaron 20 casos de septicemia; once niños fueron prematuros; en 12 la enfermedad fue de comienzo precoz; en 5 el agente infectante fue Klebsíella spp. y en otros 5 un bacilo gram negativo diferente de ésta y de Escheríchía colí. Cinco niños sufrieron, además, meningitis; cuatro de los 5 casos de meningitis ocurrieron en niños con septicemia de comienzo precoz; fallecieron 7 pacientes, de los cuales 6 hablan estado Infectados con bacilos gram negativos. El Riesgo Relativo de sufrir meningitis fue mayor entre los casos de septicemia de comienzo precoz y el de fallecer '0 fue entre los Intervenidos para corregir malformaciones congénitas y los que hablan presentado hipos la perinatal. Se llama la atenci

  14. Estudo comparativo entre métodos de coloração para a pesquisa do bacilo álcool-ácido resistente em secreções pulmonares A comparative study between two staining methods employed in the search of alcohol acid resistant bacilli in pulmonary secretions

    Directory of Open Access Journals (Sweden)

    Clara Pechmann Mendonça

    1975-03-01

    Full Text Available Apresentação do resultado comparativo entre dois métodos de coloração Osol e Ziehl-Neelsen para a pesquisa do bacilo álcool-ácido resistente, em 337 amostras secreção pulmonar. Foi realizada uma avaliação cultural de 287 amostras, mostrando que o método de Osol apresenta-se melhor nas baciloscopias discordantes e que há tendência em apresentar maior riqueza de germe.The comparative results obtained with the study of two staining methods, the Ziehl-Neelsen and the Osol ones, are presented. The study was performed with the alcohol acid resistant bacilli of 337 pulmonary secretion specimens. Evaluation cultures of 287 of these specimens were made. The Osol method proved to be better than the Ziehl-Neelsen one when dealing with discordant baciloscopic evidence. There tended to be a larger ammount of bacilli, too, when the former was used.

  15. Antioxidant activity via DPPH, gram-positive and gram-negative antimicrobial potential in edible mushrooms.

    Science.gov (United States)

    Ahmad, Nisar; Mahmood, Fazal; Khalil, Shahid Akbar; Zamir, Roshan; Fazal, Hina; Abbasi, Bilal Haider

    2014-10-01

    Edible mushrooms (EMs) are nutritionally rich source of proteins and essential amino acids. In the present study, the antioxidant activity via 1,1-diphenyl-2-picrylhydrazyl (DPPH) and antimicrobial potential in EMs (Pleurotus ostreatus, Morchella esculenta, P. ostreatus (Black), P. ostreatus (Yellow) and Pleurotus sajor-caju) were investigated. The DPPH radical scavenging activity revealed that the significantly higher activity (66.47%) was observed in Morchella esculenta at a maximum concentration. Similarly, the dose-dependent concentrations (200, 400, 600, 800 and 1000 µg) were also used for other four EMs. Pleurotus ostreatus exhibited 36.13% activity, P. ostreatus (Black (B)) exhibited 30.64%, P. ostreatus (Yellow (Y)) exhibited 40.75% and Pleurotus sajor-caju exhibited 47.39% activity at higher concentrations. Furthermore, the antimicrobial potential were investigated for its toxicity against gram-negative bacterial strains (Escherichia coli, Pseudomonas aeroginosa, Salmonella typhi, Klebsiella pneumonia, Erwinia carotovora and Agrobacterium tumifaciens), gram-positive bacterial strains (Bacillus subtilis, Bacillus atrophaeus and Staphylococcus aureus) and a fungal strain (Candida albicans) in comparison with standard antibiotics. Antimicrobial screening revealed that the ethanol extract of P. ostreatus was active against all microorganism tested except E. coli. Maximum zone of inhibition (13 mm) was observed against fungus and A. tumifaciens. P. sajor-caju showed best activities (12.5 mm) against B. subtilis, B. atrophaeus and K. pneumonia. P. ostreatus (Y) showed best activities against P. aeroginosa (21.83 mm), B. atrophaeus (20 mm) and C. albicans (21 mm). P. ostreatus (B) exhibited best activities against C. albicans (16 mm) and slightly lower activities against all other microbes except S. typhi. M. esculenta possess maximum activities in terms of inhibition zone against all microorganisms tested except S. typhi. © The Author(s) 2012.

  16. Efficacy of direct Gram stain in differentiating staphylococci from streptococci in blood cultures positive for gram-positive cocci.

    Science.gov (United States)

    Agger, W A; Maki, D G

    1978-01-01

    A preponderance of clusters seen on direct Gram stain of blood cultures positive for gram-positive cocci was 98% sensitive and 100% specific for identification of staphylococcal species or of Peptococcus. A preponderance of chains, pairs, or both was 100% sensitive and 98% specific for identifying streptococci. Further presumptive identification of either staphylococci or streptococci based on microscopic morphology was unreliable. The direct Gram stain is highly reliable for differentiating staphylococci from streptococci and should be of considerable value to clinicians selecting initial antimicrobial therapy. PMID:75888

  17. Volatile metabolites from some gram-negative bacteria

    DEFF Research Database (Denmark)

    Schöller, Charlotte; Molin, Søren; Wilkins, Ken

    1997-01-01

    A survey of volatile organic compounds (VOCs) excreted from various Gram-negative bacteria (Pseudomonas spp., Serratia spp. and Enterobacter spp.) was carried out. Compounds were identified by gas chromatography-mass spectrometry. VOCs identified included dimethyl disulphide, dimethyl trisulphide...

  18. Extended-spectrum beta-lactamase producing gram negative ...

    African Journals Online (AJOL)

    ESBL)-producing Gram- negative bacteria (GNB), particularly in Enterobacteriaceae, Acinetobacter baumannii, and Pseudomonas aeruginosa, have increased all over the world. ESBLs are characterized by their ability to hydrolyze β-lactams, ...

  19. New antimicrobial approaches to gram positive respiratory infections.

    Science.gov (United States)

    Liapikou, Adamantia; Cilloniz, Catia; Mensa, Josep; Torres, Antonio

    2015-06-01

    Nowadays, we face growing resistance among gram-positive and gram-negative pathogens that cause respiratory infection in the hospital and in the community. The spread of penicillin- and macrolide-resistant pneumococci, Community-acquired methicillin-resistant staphylococcus aureus (Ca-MRSA), the emergence of glycopeptide-resistant staphylococci underline the need for underline the need for therapeutic alternatives. A number of new therapeutic agents, with activity against the above Gram (+) respiratory pathogens, as ceftaroline, ceftopibrole, telavancin, tedizolid have become available, either in clinical trials or have been approved for clinical use. Especially, the development of new oral antibiotics, as nemonaxacin, omadacyclin, cethromycin and solithromycin will give a solution to the lack of oral drugs for outpatient treatment. In the future the clinician needs to optimize the use of old and new antibiotics to treat gram (+) respiratory serious infections. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. LexGram - a practical categorial grammar formalism -

    OpenAIRE

    Koenig, Esther

    1995-01-01

    We present the LexGram system, an amalgam of (Lambek) categorial grammar and Head Driven Phrase Structure Grammar (HPSG), and show that the grammar formalism it implements is a well-structured and useful tool for actual grammar development.

  1. Análise química, morfológica e microbiológica de negativos fotográficos do século XX

    OpenAIRE

    Coelho, Cátia Sofia Ferreira

    2015-01-01

    As películas fotográficas em acetato de celulose são propensas a degradação química, o chamado síndrome do vinagre e a degradação microbiológica por fungos e bactérias. Neste trabalho foram estudados seis negativos fotográficos de uma coleção particular. Na caracterização material dos negativos foram utilizadas técnicas de análise não destrutiva, como a fotografia, a microscopia ótica, a microscopia eletrónica de varrimento, a espetroscopia de infravermelho com transformada de ...

  2. The value of intraoperative Gram stain in revision spine surgery.

    Science.gov (United States)

    Shifflett, Grant D; Nwachukwu, Benedict U; Bjerke-Kroll, Benjamin T; Kueper, Janina; Koltsov, Jayme B; Sama, Andrew A; Girardi, Federico P; Cammisa, Frank P; Hughes, Alexander P

    2015-10-01

    Intraoperative cultures and Gram stains are often obtained in cases of revision spine surgery even when clinical signs of infection are not present. The clinical utility and cost-effectiveness of this behavior remain unproven. The aim was to evaluate the clinical utility and cost-effectiveness of routine intraoperative Gram stains in revision spine surgery. This was a retrospective clinical review performed at an academic center in an urban setting. One hundred twenty-nine consecutive adult revision spine surgeries were performed. The outcome measures included intraoperative Gram stains. We retrospectively reviewed the records of 594 consecutive revision spine surgeries performed by four senior surgeons between 2008 and 2013 to identify patients who had operative cultures and Gram stains performed. All revision cases including cervical, thoracic, and lumbar fusion and non-fusion, with and without instrumentation were reviewed. One hundred twenty-nine (21.7%) patients had operative cultures obtained and were included in the study. The most common primary diagnosis code at the time of revision surgery was pseudarthrosis, which was present in 41.9% of cases (54 of 129). Infection was the primary diagnosis in 10.1% (13 of 129) of cases. Operative cultures were obtained in 129 of 595 (21.7%) cases, and 47.3% (61 of 129) were positive. Gram stains were performed in 98 of 129 (76.0%) cases and were positive in 5 of 98 (5.1%) cases. Overall, there was no correlation between revision diagnosis and whether or not a Gram stain was obtained (p=.697). Patients with a history of prior instrumentation were more likely to have a positive Gram stain (pGram staining was found to have a sensitivity of 10.9% (confidence interval [CI] 3.9%-23.6%) and specificity of 100% (CI 93.1%-100%). The positive and negative predictive values were 100% (CI 48.0%-100%) and 57.3% (CI 45.2%-66.2%), respectively. Kappa coefficient was calculated to be 0.1172 (CI 0.0194-0.2151). The cost per discrepant

  3. Chocolate agar, a differential medium for gram-positive cocci.

    OpenAIRE

    Gunn, B A

    1984-01-01

    Reactions incurred on chocolate agar by gram-positive cocci were correlated with species identity. Darkening and clearing of the medium was usually associated with the species Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus simulans, and Streptococcus faecalis. Yellowing of chocolate agar was associated with alpha-hemolytic species of Streptococcus. The study demonstrated that reactions occurring on chocolate agar are useful in identifying gram-positive cocci.

  4. Pulmonary infiltrates during community acquired Gram-negative bacteremia

    DEFF Research Database (Denmark)

    Fjeldsøe-Nielsen, Hans; Gjeraa, Kirsten; Berthelsen, Birgitte G

    2013-01-01

    The primary aim of this study was to describe the frequency of pulmonary infiltrates on chest X-ray (CXR) during community acquired Gram-negative bacteremia at a single centre in Denmark.......The primary aim of this study was to describe the frequency of pulmonary infiltrates on chest X-ray (CXR) during community acquired Gram-negative bacteremia at a single centre in Denmark....

  5. Selective bowel decontamination results in gram-positive translocation.

    Science.gov (United States)

    Jackson, R J; Smith, S D; Rowe, M I

    1990-05-01

    Colonization by enteric gram-negative bacteria with subsequent translocation is believed to be a major mechanism for infection in the critically ill patient. Selective bowel decontamination (SBD) has been used to control gram-negative infections by eliminating these potentially pathogenic bacteria while preserving anaerobic and other less pathogenic organisms. Infection with gram-positive organisms and anaerobes in two multivisceral transplant patients during SBD led us to investigate the effect of SBD on gut colonization and translocation. Twenty-four rats received enteral polymixin E, tobramycin, amphotericin B, and parenteral cefotaxime for 7 days (PTA + CEF); 23 received parenteral cefotaxime alone (CEF), 19 received the enteral antibiotics alone (PTA), 21 controls received no antibiotics. Cecal homogenates, mesenteric lymph node (MLN), liver, and spleen were cultured. Only 8% of the PTA + CEF group had gram-negative bacteria in cecal culture vs 52% CEF, 84% PTA, and 100% in controls. Log Enterococcal colony counts were higher in the PTA + CEF group (8.0 + 0.9) vs controls (5.4 + 0.4) P less than 0.01. Translocation of Enterococcus to the MLN was significantly increased in the PTA + CEF group (67%) vs controls (0%) P less than 0.01. SBD effectively eliminates gram-negative organisms from the gut in the rat model. Overgrowth and translocation of Enterococcus suggests that infection with gram-positive organisms may be a limitation of SBD.

  6. Gram's Stain Does Not Cross the Bacterial Cytoplasmic Membrane.

    Science.gov (United States)

    Wilhelm, Michael J; Sheffield, Joel B; Sharifian Gh, Mohammad; Wu, Yajing; Spahr, Christian; Gonella, Grazia; Xu, Bolei; Dai, Hai-Lung

    2015-07-17

    For well over a century, Hans Christian Gram's famous staining protocol has been the standard go-to diagnostic for characterizing unknown bacteria. Despite continuous and ubiquitous use, we now demonstrate that the current understanding of the molecular mechanism for this differential stain is largely incorrect. Using the fully complementary time-resolved methods: second-harmonic light-scattering and bright-field transmission microscopy, we present a real-time and membrane specific quantitative characterization of the bacterial uptake of crystal-violet (CV), the dye used in Gram's protocol. Our observations contradict the currently accepted mechanism which depicts that, for both Gram-negative and Gram-positive bacteria, CV readily traverses the peptidoglycan mesh (PM) and cytoplasmic membrane (CM) before equilibrating within the cytosol. We find that not only is CV unable to traverse the CM but, on the time-scale of the Gram-stain procedure, CV is kinetically trapped within the PM. Our results indicate that CV, rather than dyes which rapidly traverse the PM, is uniquely suited as the Gram stain.

  7. Silver enhances antibiotic activity against gram-negative bacteria.

    Science.gov (United States)

    Morones-Ramirez, J Ruben; Winkler, Jonathan A; Spina, Catherine S; Collins, James J

    2013-06-19

    A declining pipeline of clinically useful antibiotics has made it imperative to develop more effective antimicrobial therapies, particularly against difficult-to-treat Gram-negative pathogens. Silver has been used as an antimicrobial since antiquity, yet its mechanism of action remains unclear. We show that silver disrupts multiple bacterial cellular processes, including disulfide bond formation, metabolism, and iron homeostasis. These changes lead to increased production of reactive oxygen species and increased membrane permeability of Gram-negative bacteria that can potentiate the activity of a broad range of antibiotics against Gram-negative bacteria in different metabolic states, as well as restore antibiotic susceptibility to a resistant bacterial strain. We show both in vitro and in a mouse model of urinary tract infection that the ability of silver to induce oxidative stress can be harnessed to potentiate antibiotic activity. Additionally, we demonstrate in vitro and in two different mouse models of peritonitis that silver sensitizes Gram-negative bacteria to the Gram-positive-specific antibiotic vancomycin, thereby expanding the antibacterial spectrum of this drug. Finally, we used silver and antibiotic combinations in vitro to eradicate bacterial persister cells, and show both in vitro and in a mouse biofilm infection model that silver can enhance antibacterial action against bacteria that produce biofilms. This work shows that silver can be used to enhance the action of existing antibiotics against Gram-negative bacteria, thus strengthening the antibiotic arsenal for fighting bacterial infections.

  8. Riesgo de resultados negativos asociados a inhibidores de la bomba de protones: revisión de las prescripciones electrónicas en pacientes polimedicados

    Directory of Open Access Journals (Sweden)

    Luis A. Martínez López

    2017-06-01

    Full Text Available Introducción: El elevado consumo de inhibidores de la bomba de protones (IBP puede incrementar la probabilidad de aparición de interacciones clínicamente relevantes. Pacientes mayores, polimedicados y pluripatológicos representan un grupo de alto riesgo. Se espera que la revisión sistemática de las prescripciones electrónicas (PE permita detectar potenciales interacciones farmacológicas. Material y métodos: Estudio retrospectivo, transversal y observacional: revisión de las PE de IBP dispensadas entre enero y diciembre de 2015 en una farmacia comunitaria rural. Resultados: 1.186 PE, 164 pacientes (edad 65,7±17,2. Mayor número de pacientes en rango de edad 71-80 (n=52. Medicamentos por paciente: 11,0±5,6. PE IBP sin indicación aprobada: 27%. Indicación mayoritaria: protección frente a gastrolesión (77%. 29 pacientes (30% con riesgo de resultados negativos asociados a la medicación (RNM por omeprazol, 15 de ellos sin indicación. Patologías concomitantes más prevalentes: hipertensión arterial (n=81, dislipemia (n=61 y diabetes (n=36. Principios activos implicados: acenocumarol, hierro, cianocobalamina, escitalopram, benzodiazepinas y clopidogrel. Discusión: El 80% de las PE de omeprazol corresponde a pacientes entre 61 y 90 años, la mayoría con comorbilidad y polifarmacia, y supera el tiempo de tratamiento recomendado. Relacionamos la cronificación y el aumento del riesgo de RNM con la ausencia de un seguimiento adecuado. Muchos fármacos corresponsables del riesgo tratan los problemas de salud (PS más prevalentes de nuestra población: la probabilidad de interacción resulta independiente de la correcta indicación del IBP. Conclusiones: La revisión de las PE permite valorar el riesgo de RNM y evaluar la información básica relativa al riesgo de interacción. Se detectaron RNM de no necesidad y de inseguridad en proporciones comparables. Un número elevado de PE de omeprazol tienden a cronificarse. Las interacciones m

  9. Fatores associados à agressão física em gestantes e os desfechos negativos no recém-nascido

    Directory of Open Access Journals (Sweden)

    Elaine Fernandes Viellas

    2013-02-01

    Full Text Available OBJETIVO: Verificar os fatores socioeconômicos, demográficos e reprodutivos associados à agressão física na gestação e os desfechos negativos para o recém-nascido em dois grupos de mulheres: adolescentes e adultas jovens. MÉTODO: Estudo transversal com uma amostra de 8.961 puérperas que se hospitalizaram em maternidades do município do Rio de Janeiro por ocasião do parto. Para testar hipótese de homogeneidade de proporções foi utilizado o teste χ². A razão de chances e os intervalos de confiança foram estimados através de regressão logística. RESULTADOS: Foi apontado que 5% das adolescentes e 2,5% das adultas jovens sofreram agressão física na gravidez. Em ambos os grupos, as variáveis associadas com o abuso físico foram: menor nível de escolaridade, menor apoio do pai da criança e maior tentativa de interrupção da gestação. O aumento no consumo de bebida alcoólica mostrou associação com o abuso físico apenas no grupo de adolescentes, e o uso de drogas ilícitas somente entre as adultas jovens. Os filhos das puérperas agredidas tiveram duas vezes mais chances de óbito neonatal, e três vezes mais de óbito pós-neonatal. Por outro lado, a assistência pré-natal de boa qualidade reduziu a chance de agressão física durante a gestação. CONCLUSÕES: Os resultados alertam para o aumento da chance de óbito neonatal e pós-neonatal entre os filhos das vítimas de agressão física durante a gestação e apontam para a importância do pré-natal na identificação de mulheres sob maior risco de episódios violentos, momento oportuno para o desenvolvimento de ações de proteção e cuidado à mãe e ao bebê.

  10. Pensamentos negativos automáticos em pacientes com transtorno do pânico (Automatic Negative Thought in Patients with Panic Disorder

    Directory of Open Access Journals (Sweden)

    José Maria Montiel

    2014-12-01

    Full Text Available RESUMO: O transtorno do pânico (TP é caracterizado por ataques de pânico, os quais surgem acompanhados por uma série de pensamentos inadequados ao contexto. Objetivo: identificar e sistematizar a distorção cognitiva e os tipos de pensamentos negativos automáticos (PNA presentes em pacientes com TP. Participantes: 20 indivíduos na faixa etária de 32 anos e com diagnóstico de TP. Instrumentos: Anamnese e entrevista semi-estruturada, Inventário Beck de Ansiedade e Escala para Pânico e Agorafobia. Resultados: os dados apontaram níveis de ansiedade significativos, corroborando o diagnóstico de transtorno do pânico nos sujeitos. Já os PNA - como «Estou com dor de cabeça. Será que é uma crise?» - e os padrões de distorções cognitivas identificados, incluindo suposição, catastrofização, generalização e subestimação/ superestimação, estão em acordo com a literatura apresentada e são condizentes com a prática clínica. ABSTARCT: Panic disorder (PD is characterized by attacks of panic, which are accompanied by a series of thoughts, inappropriate to the context. Objective: to identify and systematize the cognitive distortion and the types of automatic negative thoughts (ANT present in patients with (PD. Participants: 20 individuals in the age of 32 years and with a diagnosis of PD. Instruments: Anamnesis and semi-structured interview, Beck anxiety inventory and scale of panic and agoraphobia. Results: data showed significant levels of anxiety, corroborating the diagnosis of disorders of panic in the subjects. Already the ANT - as «I have a headache. Is it a crisis?» - and the standards identified cognitive distortions, including assumptions, pessimism, generalization and under-estimation / over-estimation, they are subject to the presented literature and they are suitable for clinical practice.

  11. Antibacterial activity and interactions of plant essential oil combinations against Gram-positive and Gram-negative bacteria

    OpenAIRE

    Cristina Anamaria Semeniuc; Carmen Rodica Pop; Ancuţa Mihaela Rotar

    2017-01-01

    The aim of this study was to compare the antibacterial effects of several essential oils (EOs) alone and in combination against different Gram-positive and Gram-negative bacteria associated with food products. Parsley, lovage, basil, and thyme EOs, as well as their mixtures (1:1, v/v), were tested against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Salmonella typhimurium. The inhibitory effects ranged from strong (thyme EO against E. coli) to no inhib...

  12. O estatuto de nem na gramática do português

    Directory of Open Access Journals (Sweden)

    Norma Barbosa Novaes Marques

    2016-08-01

    Full Text Available Tradicionalmente a partícula ‘nem’ tem sido considerada uma conjunção aditiva, pois se entende que estabelece entre elementos uma relação de acréscimo. Etimologicamente, é proveniente do latim ‘nec’, um dos poucos juntores que restaram nas variedades vernáculas de latim, juntamente com ‘et’, ‘aut’, ‘magis’, ‘ca’, ‘post’ (cf. Nascentes, 1955. Para Neves (2000, ‘nem’ tem o mesmo papel de ‘e’, ou seja, é uma conjunção que marca uma relação de adição entre segmentos negativos coordenados, com significado básico de “e também não”. Como se pode observar, a autora considera ‘nem’ um elemento complexo, indicando acréscimo por meio de ‘e’ e ‘também’, e negação, por meio de ‘não’. Este trabalho tem como objetivo discutir o estatuto desse elemento, utilizando o aparato teórico da Gramática Discursivo-Funcional (HENGEVELD; MACKENZIE, 2008, tendo como hipótese a de que ‘nem’, tal como ‘não’, representa, morfossintaticamente, o operador de polaridade negativa, acrescida, no entanto, de ênfase. Para isso, utiliza o córpus do Projeto PHPB, constituído de documentos escritos no Brasil, dos séculos XVII ao XX. Os dados analisados revelam que ‘nem’ pode ocorrer numa relação de justaposição entre atos discursivos, ou entre termos de diferentes categorias semânticas, e representa, além da negação, uma estratégia de intensificação, utilizada pelo Falante para atingir seu propósito comunicativo.  

  13. Mars-GRAM 2010: Additions and Resulting Improvements

    Science.gov (United States)

    Justh, Hilary L.; Burns, K. Lee

    2013-01-01

    The Mars Global Reference Atmospheric Model (Mars-GRAM) is an engineering-level atmospheric model widely used for diverse mission applications. Mars-GRAM has been utilized during previous aerobraking operations in the atmosphere of Mars. Mars-GRAM has also been used in the prediction and validation of Mars Pathfinder hypersonic aerodynamics, the aerothermodynamic and entry dynamics studies for Mars Polar Lander, the landing site selection process for the Mars Science Laboratory (MSL), the Mars Aerocapture System Study (MASS) as well as the Aerocapture Technology Assessment Group (TAG). Most recently, Mars-GRAM 2010 was used to develop the onboard atmospheric density estimator that is part of the Autonomous Aerobraking Development Plan. The most recent release of Mars-GRAM 2010 contains several changes including an update to Fortran 90/95 and the addition of adjustment factors. Following the completion of a comparison analysis between Mars-GRAM, Thermal Emission Spectrometer (TES), as well as Mars Global Surveyor (MGS), Mars Odyssey (ODY), and Mars Reconnaissance Orbiter (MRO) aerobraking density data, adjustment factors were added to Mars-GRAM 2010 that alter the input data from National Aeronautics and Space Administration (NASA) Ames Mars General Circulation Model (MGCM) and the University of Michigan Mars Thermospheric General Circulation Model (MTGCM) for the mapping year 0 user-controlled dust case. The addition of adjustment factors resolved the issue of previous versions of Mars-GRAM being less than realistic when used for sensitivity studies for mapping year 0 and large optical depth values, such as tau equal to 3. Mars-GRAM was evaluated at locations and times of TES limb observations and adjustment factors were determined. For altitudes above 80 km and below 135 km, Mars-GRAM (MTGCM) densities were compared to aerobraking densities measured by Mars Global Surveyor (MGS), Mars Odyssey (ODY), and Mars Reconnaissance Orbiter (MRO) to determine the adjustment

  14. Antimicrobial Peptide Resistance Mechanisms of Gram-Positive Bacteria.

    Science.gov (United States)

    Nawrocki, Kathryn L; Crispell, Emily K; McBride, Shonna M

    2014-10-13

    Antimicrobial peptides, or AMPs, play a significant role in many environments as a tool to remove competing organisms. In response, many bacteria have evolved mechanisms to resist these peptides and prevent AMP-mediated killing. The development of AMP resistance mechanisms is driven by direct competition between bacterial species, as well as host and pathogen interactions. Akin to the number of different AMPs found in nature, resistance mechanisms that have evolved are just as varied and may confer broad-range resistance or specific resistance to AMPs. Specific mechanisms of AMP resistance prevent AMP-mediated killing against a single type of AMP, while broad resistance mechanisms often lead to a global change in the bacterial cell surface and protect the bacterium from a large group of AMPs that have similar characteristics. AMP resistance mechanisms can be found in many species of bacteria and can provide a competitive edge against other bacterial species or a host immune response. Gram-positive bacteria are one of the largest AMP producing groups, but characterization of Gram-positive AMP resistance mechanisms lags behind that of Gram-negative species. In this review we present a summary of the AMP resistance mechanisms that have been identified and characterized in Gram-positive bacteria. Understanding the mechanisms of AMP resistance in Gram-positive species can provide guidelines in developing and applying AMPs as therapeutics, and offer insight into the role of resistance in bacterial pathogenesis.

  15. Compact q-gram Profiling of Compressed Strings

    DEFF Research Database (Denmark)

    Bille, Philip; Cording, Patrick Hagge; Gørtz, Inge Li

    2013-01-01

    We consider the problem of computing the q-gram profile of a string T of size N compressed by a context-free grammar with n production rules. We present an algorithm that runs in O(N − α) expected time and uses O(n + k T , q ) space, where N − α ≤ qn is the exact number of characters decompressed...... by the algorithm and k T , q  ≤ N − α is the number of distinct q-grams in T . This simultaneously matches the current best known time bound and improves the best known space bound. Our space bound is asymptotically optimal in the sense that any algorithm storing the grammar and the q-gram profile must use Ω(n + k...... T , q ) space. To achieve this we introduce the q-gram graph that space-efficiently captures the structure of a string with respect to its q-grams, and show how to construct it from a grammar....

  16. Compact q-gram profiling of compressed strings

    DEFF Research Database (Denmark)

    Bille, Philip; Cording, Patrick Hagge; Gørtz, Inge Li

    2014-01-01

    We consider the problem of computing the q-gram profile of a string T of size N compressed by a context-free grammar with n production rules. We present an algorithm that runs in O(N−α) expected time and uses O(n+q+kT,q) space, where N−α≤qnN−α≤qn is the exact number of characters decompressed...... by the algorithm and kT,q≤N−α is the number of distinct q-grams in T . This simultaneously matches the current best known time bound and improves the best known space bound. Our space bound is asymptotically optimal in the sense that any algorithm storing the grammar and the q-gram profile must use Ω......(n+q+kT,q) space. To achieve this we introduce the q-gram graph that space-efficiently captures the structure of a string with respect to its q-grams, and show how to construct it from a grammar....

  17. A chromatographic approach to distinguish Gram-positive from Gram-negative bacteria using exogenous volatile organic compound metabolites.

    Science.gov (United States)

    Ramírez-Guízar, Susana; Sykes, Hannah; Perry, John D; Schwalbe, Edward C; Stanforth, Stephen P; Perez-Perez, Ma Cristina I; Dean, John R

    2017-06-09

    This paper utilized L-alanine aminopeptidase activity as a useful approach to distinguish between Gram-negative and Gram-positive bacteria. This was done using two enzyme substrates, specifically 2-amino-N-phenylpropanamide and 2-amino-N-(4-methylphenyl)propanamide which liberated the volatile compounds aniline and p-toluidine, respectively. Two complementary analytical techniques have been used to identify and quantify the VOCs, specifically static headspace multicapillary column gas chromatography ion mobility spectrometry (SHS-MCC-GC-IMS) and headspace solid phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS). Superior limits of detection were obtained using HS-SPME-GC-MS, typically by a factor of x6 such that the LOD for aniline was 0.02μg/mL and 0.01μg/mL for p-toluidine. In addition, it was also possible to determine indole interference-free by HS-SPME-GC-MS at an LOD of 0.01μg/mL. The approach was applied to a range of selected bacteria: 15 Gram-negative and 7 Gram-positive bacteria. Use of pattern recognition, in the form of Principal Component Analysis, confirmed that it is possible to differentiate between Gram-positive and Gram-negative bacteria using the enzyme generated VOCs, aniline and p-toluidine. The exception was Stenotrophomonas maltophilia which showed negligible VOC concentrations for both aniline and p-toluidine, irrespective of the analytical techniques used and hence was not characteristic of the other Gram-negative bacteria investigated. The developed methodology has the potential to be applied for clinical and food applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Minimal and mild endometriosis negatively impact on pregnancy outcome Endometriose mínima e leve e seu impacto negativo sobre a gravidez

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Pina Carvalho

    2012-10-01

    ] foram identificados por busca na base de dados MEDLINE, de 1985 a setembro de 2011. Os seguintes termos foram usados como palavras-chave: endometriose, infertilidade, taxa de gravidez; estágio mínimo; estágio leve de endometriose. Entre janeiro de 1985 e novembro de 2011, 1188 artigos foram recuperados; com base no título, 1038 citações foram excluídas e, finalmente, depois de critérios de inclusão e exclusão, 18 artigos foram selecionados para fazer parte desta revisão sistemática. Várias razões têm sido discutidas na literatura na tentativa de explicar o impacto da endometriose mínima no resultado da fertilidade, tais como: disfunção ovulatória, foliculogênese alterada prejudicada, defeito na implantação, baixa qualidade embrionária, ambiente peritoneal inflamatório e hostil e problemas da fase lútea. Apesar de toda polêmica envolvendo o tópico, o maior ensaio clínico randomizado foi publicado por Marcoux et al. Os autores encontraram uma taxa de gravidez estatisticamente significante após a ressecção de lesões superficiais de endometriose. Estágios iniciais de endometriose desempenham um papel crítico relacionado à infertilidade e, provavelmente proporcionam um impacto negativo nas taxas de gravidez em pacientes com endometriose. Outros estudos envolvendo estágios iniciais de endometriose, especialmente ensaios clínicos randomizados, ainda precisam ser realizados.

  19. Insights into Newer Antimicrobial Agents against Gram-negative Bacteria

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    Neelam Yaneja

    2016-01-01

    Full Text Available Currently, drug resistance, especially against cephalosporins and carbapenems, among gram-negative bacteria is an important challenge, which is further enhanced by the limited availability of drugs against these bugs. There are certain antibiotics (colistin, fosfomycin, temocillin, and rifampicin that have been revived from the past to tackle the menace of superbugs, including members of Enterobacteriaceae, Acinetobacter species, and Pseudomonas species. Very few newer antibiotics have been added to the pool of existing drugs. There are still many antibiotics that are passing through various phases of clinical trials. The initiative of Infectious Disease Society of America to develop 10 novel antibiotics against gram-negative bacilli by 2020 is a step to fill the gap of limited availability of drugs. This review aims to provide insights into the current and newer drugs in pipeline for the treatment of gram-negative bacteria and also discusses the major challenging issues for their management.

  20. Direct gram stain and urease test to detect Helicobacter pylori.

    Science.gov (United States)

    Van Horn, K G; Dworkin, B M

    1990-01-01

    Antral biopsies were obtained by gastrointestinal endoscopy on 143 adult patients with dyspeptic symptoms of gastritis or peptic ulcer disease. A direct Gram stain and a direct urease test were performed on each biopsy in addition to culture. Forty-three biopsies (30%) were considered positive for Helicobacter pylori based on culture or histologic examination, or both. Thirty-one biopsies (72% sensitivity) were positive for both direct tests, whereas 95 of 100 negative cultures were negative for both tests. Thirty-eight of the 43 positive biopsies were Gram stain positive (sensitivity, 88%; specificity, 100%). The direct urease test alone was positive at 4 hr for 29 biopsies (sensitivity, 67%; specificity, 100%) and at 24 hr for 38 biopsies (sensitivity, 74%; specificity, 95%). Rapid presumptive diagnosis of H. pylori in antral biopsies was obtained when at least one direct test, Gram stain or urease, was positive.

  1. Atividade antimicrobiana dos extratos de folhas e ramos da Ilex paraguariensis A. St.-Hil., Aquifoliaceae

    Directory of Open Access Journals (Sweden)

    Bruno De Biasi

    Full Text Available Para avaliação da atividade antimicrobiana de Ilex paraguariensis foram utilizados seis microrganismos: Candida albicans, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus e Staphylococcus epidermidis. O método utilizado foi de difusão do disco. Foram adicionados em discos de papel filtro 10 µl de extratos hidro-alcoólicos das folhas e ramos coletados de dois ambientes distintos, com e sem exposição ao sol. As placas foram incubadas a 35- 37 ºC por 24 h. Os extratos inibiram levedura, bacilos gram-negativos e cocos gram-positivos, não mostrando atividade frente à Escherichia coli.

  2. Suetônio, dos gramáticos

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    Marcos Martinho

    2014-12-01

    Full Text Available O Dos gramáticos de Suetônio divide-se em duas partes: na primeira, o autor narra a introdução, desenvolvimento, florescimento e declínio da gramática em Roma (1-4; na segunda, expõe a biografia de vinte professores de gramática, que ensinaram na Cidade entre o início do séc.  I a.C. e meados do século seguinte (5-24. Quanto à primeira parte, procuro mostrar que Suetônio adota conceitos fisicistas ou naturalistas para narrar a história da gramática em Roma, de modo que aquela se possa comparar à vida de um ser vivo. Assim, a exposição de Suetônio revela-se, na verdade, antes biográfica que historicista. Quanto à segunda parte, procuro mostrar que o Biógrafo se interessa por gramáticos que não só escreveram sobre sua arte no ócio, mas a ensinaram por ofício, isto é, por professores de gramática. Daí, seleciono e comento os elementos narrativos relacionados à docência, a saber: os métodos de ensino, o lugar de ensino, o número e qualidade dos alunos, os preços e honorários dos professores. Por fim, apresento tradução anotada do texto de Suetônio.

  3. Glycosaminoglycans are involved in pathogen adherence to corneal epithelial cells differently for Gram-positive and Gram-negative bacteria

    Directory of Open Access Journals (Sweden)

    Beatriz García

    2016-11-01

    Full Text Available The epithelium of the cornea is continuously exposed to pathogens, and adhesion to epithelial cells is regarded as an essential first step in bacterial pathogenesis. In this article, the involvement of glycosaminoglycans in the adhesion of various pathogenic bacteria to corneal epithelial cells is analyzed. All microorganisms use glycosaminoglycans as receptors, but arranged in different patterns depending on the Gram-type of the bacterium. The heparan sulfate chains of syndecans are the main receptors, though other molecular species also seem to be involved, particularly in Gram-negative bacteria. Adherence is inhibited differentially by peptides, including heparin binding sequences, indicating the participation of various groups of Gram-positive and -negative adhesins. The length of the saccharides produces a major effect, and low molecular weight chains inhibit the binding of Gram-negative microorganisms but increase the adherence of Gram-positives. Pathogen adhesion appears to occur preferentially through sulfated domains, and is very dependent on N- and 6-O-sulfation of the glucosamine residue and, to a lesser extent, 2-O sulfation of uronic acid. These data show the differential use of corneal receptors, which could facilitate the development of new anti-infective strategies.

  4. Mechanisms of Antimicrobial Peptide Resistance in Gram-Negative Bacteria

    Directory of Open Access Journals (Sweden)

    Victor I. Band

    2014-12-01

    Full Text Available Cationic antimicrobial peptides (CAMPs are important innate immune defenses that inhibit colonization by pathogens and contribute to clearance of infections. Gram-negative bacterial pathogens are a major target, yet many of them have evolved mechanisms to resist these antimicrobials. These resistance mechanisms can be critical contributors to bacterial virulence and are often crucial for survival within the host. Here, we summarize methods used by Gram-negative bacteria to resist CAMPs. Understanding these mechanisms may lead to new therapeutic strategies against pathogens with extensive CAMP resistance.

  5. Cellular reprogramming by gram-positive bacterial components: a review.

    LENUS (Irish Health Repository)

    Buckley, Julliette M

    2012-02-03

    LPS tolerance has been the focus of extensive scientific and clinical research over the last several decades in an attempt to elucidate the sequence of changes that occur at a molecular level in tolerized cells. Tolerance to components of gram-positive bacterial cell walls such as bacterial lipoprotein and lipoteichoic acid is a much lesser studied, although equally important, phenomenon. This review will focus on cellular reprogramming by gram-positive bacterial components and examines the alterations in cell surface receptor expression, changes in intracellular signaling, gene expression and cytokine production, and the phenomenon of cross-tolerance.

  6. Inhibition of Multidrug-Resistant Gram-Positive and Gram-Negative Bacteria by a Photoactivated Porphyrin.

    Science.gov (United States)

    Bondi, Moreno; Mazzini, Anna; de Niederhäusern, Simona; Iseppi, Ramona; Messi, Patrizia

    2017-12-04

    The authors studied the in vitro antibacterial activity of the photo-activated porphyrin meso-tri(N-methyl-pyridyl), mono(N-tetradecyl-pyridyl)porphine (C14) against four multidrug-resistant bacteria: Staphylococcus aureus, Enterococcus faecalis (Gram-positive), Escherichia coli, Pseudomonas aeruginosa (Gram-negative). Using 10 μg/ml of porphyrin and 60 sec irradiation we observed the remarkable susceptibility of S. aureus and E. faecalis to treatment while, under the same conditions, E. coli and P. aeruginosa showed very low susceptibility. In a later stage, suspensions of Gram-negative bacteria were processed with EDTA before photo-activation, obtaining a significant decrease in viable counts. In view of the results, if the combination of low porphyrin concentrations and short irradiation times will be effective in vivo also, this approach could be a possible alternative to antibiotics, in particular against localized infections due to multidrug-resistant microorganisms.

  7. Comparing word, character, and phoneme n-grams for subjective utterance recognition

    NARCIS (Netherlands)

    Wilson, T.; Raaijmakers, S.A.

    2008-01-01

    In this paper, we compare the performance of classifiers trained using word n-grams, character n-grams, and phoneme n-grams for recognizing subjective utterances in multiparty conversation. We show that there is value in using very shallow linguistic representations, such as character n-grams, for

  8. Probing interaction of Gram-positive and Gram-negative bacterial cells with ZnO nanorods

    International Nuclear Information System (INIS)

    Jain, Aanchal; Bhargava, Richa; Poddar, Pankaj

    2013-01-01

    In the present work, the physiological effects of the ZnO nanorods on the Gram positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli and Aerobacter aerogenes) bacterial cells have been studied. The analysis of bacterial growth curves for various concentrations of ZnO nanorods indicates that Gram positive and Gram negative bacterial cells show inhibition at concentrations of ∼ 64 and ∼ 256 μg/mL respectively. The marked difference in susceptibility towards nanorods was also validated by spread plate and disk diffusion methods. In addition, the scanning electron micrographs show a clear damage to the cells via changed morphology of the cells from rod to coccoid etc. The confocal optical microscopy images of these cells also demonstrate the reduction in live cell count in the presence of ZnO nanorods. These, results clearly indicate that the antibacterial activity of ZnO nanorods is higher towards Gram positive bacterium than Gram negative bacterium which indicates that the structure of the cell wall might play a major role in the interaction with nanostructured materials and shows high sensitivity to the particle concentration. Highlights: ► Effect of ZnO nanorods on the growth cycles of four bacterial strains. ► A relation has been established between growth rate of bacteria and concentration. ► Serious damage in the morphology of bacterial cells in the presence of ZnO nanorods. ► Microscopic studies to see the time dependent effect on bacterial cells

  9. Utilidad de la espectrometría de masas MALDI-TOF en la identificación de bacterias anaerobias

    Directory of Open Access Journals (Sweden)

    Mariela S Zárate

    Full Text Available El análisis de espectrometría de masas mediante la metodología hoy conocida como MALDI-TOF MS (Matrix-assited laser desorption/ionization time-of-flight mass spectrometry se ha convertido en un recurso de referencia para la identificación de microorganismos en microbiología clínica. No obstante, los datos relativos a algunos grupos de microorganismos son todavía controvertidos. El objetivo del presente estudio fue determinar la utilidad del MALDI-TOF MS para la identificación de aislamientos clínicos de bacterias anaerobias. Se analizaron 106 aislamientos de bacterias anaerobias mediante MALDI-TOF MS y por pruebas bioquímicas convencionales. En aquellos casos en los que la identificación por metodología convencional no era aplicable o frente a una discordancia de resultados entre las metodologías citadas, se realizó la secuenciación del gen 16S del ARNr. El método convencional y el MALDI-TOF MS coincidieron a nivel de género y especie en un 95,3 % de los casos considerando la totalidad de los aislamientos estudiados. Al considerar solo el conjunto de los bacilos gram negativos, la coincidencia fue del 91,4 %; entre los bacilos gram positivos, fue del 100 %; los 8 aislados de cocos gram positivos estudiados coincidieron y también hubo coincidencia en el único coco gram negativo incluido. Los datos obtenidos en este estudio demuestran que el MALDI-TOF MS ofrece la posibilidad de llegar a una adecuada identificación de bacterias anaerobias.

  10. Relation between Gram-stain and clinical criteria for diagnosing bacterial vaginosis with special reference to Gram grade II evaluation.

    Science.gov (United States)

    Taylor-Robinson, D; Morgan, D J; Sheehan, M; Rosenstein, I J; Lamont, R F

    2003-01-01

    The aim of this study was to analyse how the results of Gram-staining vaginal smears correlated with the clinical criteria for determining the existence of bacterial vaginosis (BV) and, in particular, how the category defined as 'intermediate' or Gram grade II did so and its significance. Women attending an antenatal clinic with an abnormal vaginal flora, that is those who had Gram-stains of grades II or III, the latter considered to equate with BV, were given clindamycin or a placebo intravaginally and examined again on up to three occasions. Gram-stain readings of grade III correlated with the clinical criteria for BV on 356 (91.7%) of 388 occasions. Grade II readings covered the spectrum of clinical criteria and correlated with those for BV on 35 (37.2%) of 94 occasions. Grade I, recorded 231 times and seen usually after clindamycin treatment, was associated with BV only once. The sensitivity, specificity, positive predictive value and negative predictive value of the Gram stain for the diagnosis of BV, based on a combination of grades II and III, were 99.7%, 71.6%, 81% and 99.6%, respectively; based on grade III only, the values were 99.7%, 87.7%, 91.6% and 99.6%, respectively. Women reported a malodorous vaginal discharge on 49.2% of the occasions a grade III flora was seen and 13.3% of the times grade II was recorded. It was not associated with grade I and would seem a useful adjunct to the accepted clinical criteria for diagnosing BV. Each of the clinical criteria was found in about equal proportions (87%-91%) for women whose Gram grade was III. For grade II, an increased discharge was noted most often (76.5%) and 'clue' cells least often (24.5%). A positive amine test was the most specific, being associated with Gram-stain diagnosis and not one that can be made clinically. It is important to recognize as a distinct entity not only because amalgamation with grade III diminishes the specificity and positive predictive value of the Gram-stain for diagnosing BV

  11. Evaluación neurológica y neurosicológica de niños VIH positivos y VIH negativos, en Medellín, Colombia, 2007

    Directory of Open Access Journals (Sweden)

    Gabriel Jaime Vélez Rengifo

    2008-11-01

    Full Text Available INTRODUCCIÓN: este estudio describe algunas características cognitivas y físicas de un grupo de 23 niños infectados con el VIH y uno de 25 niños no infectados con dicho virus, pareados por edad y sexo, en Medellín, Colombia. Se hicieron examen neurológico y pruebas neurosicológicas como WISC III, McCarthy, Wisconsin, Stroop, TMT y curva de memoria visual. OBJETIVO: describir las características neurológicas y neurosicológicas de un grupo de niños con VIH y compararlas con las de un grupo de niños VIH negativos. MÉTODO: se realizo un estudio descriptivo de corte tranversal. RESULTADOS: el desempeño cognitivo de los niños mayores de 6 años y VIH positivos tuvo una media de 88,58 y el del grupo VIH negativo de 88,36 (p = 0,973. Once de 17 pacientes (67,4% mayores de 6 años VIH positivos tuvieron desempeño cognitivo promedio (90-109. La media del perímetro cefálico del grupo de niños VIH positivos fue 51 cm y la de los niños VIH negativos, 51,12 cm (p = 0,878; no se encontró microcefalia en los niños VIH positivos. Las demás pruebas tampoco mostraron diferencias significativas entre ambos grupos. CONCLUSIONES: en comparación con los niños VIH negativos, los VIH positivos estudiados no presentan microcefalia, disminución del desempeño cognitivo ni otras alteraciones neurosicológicas, lo que puede explicarse por un tratamiento farmacológico adecuado y continuo, pero es ideal hacerles seguimiento para conocer mejor el impacto de la enfermedad.

  12. Fluoroquinolone susceptibilities to methicillin-resistant and susceptible coagulase-negative Staphylococcus isolated from eye infection Suscetibilidade dos Staphylococcus coagulase negativo meticilina-resistentes e suscetíveis isolados em infecções oculares

    Directory of Open Access Journals (Sweden)

    Adália Dias Dourado Oliveira

    2007-03-01

    Full Text Available PURPOSE: To evaluate the fluoroquinolone susceptibilities of ocular isolate coagulase-negative staphylococci (CoNS, identified at the Microbiology Laboratory - UNIFESP. DESIGN: Experimental laboratory investigation. METHODS: The minimum inhibitory concentrations (MICs of 21 strains of methicillin-resistant coagulase-negative staphylococci (MRCoNS and 22 methicillin-sensitive coagulase-negative staphylococci (MSCoNS to ciprofloxacin, ofloxacin, gatifloxacin and moxifloxacin were determined, using the E-test method standardized by the Clinical and Laboratory Standards Institute (CLSI/NCCLS. RESULTS: The MIC90s (µg/ml for the second generation of tested fluoroquinolones were higher than the fourth generation, especially for the methicillin-resistant coagulase-negative staphylococci group. CONCLUSION: Our results indicate that methicillin-sensitive coagulase-negative staphylococci are more susceptible to quinolones than are methicillin-resistant coagulase-negative staphylococci and that fourth generation fluoroquinolones appear to be more potent, affecting even coagulase-negative staphylococcal strains resistant to second generation fluoroquinolones.OBJETIVOS: Avaliar a suscetibilidade a fluorquinolonas dos Staphylococcus coagulase-negativo (SCoN identificados no Laboratório de Microbiologia Ocular da Unifesp. MÉTODOS: Foi determinada a concentração inibitória mínima de 21 cepas de SCoN meticilina-resistentes e 22 meticilina-sensíveis para ciprofloxacina, ofloxacina, gatifloxacina e moxifloxacina, utilizando o E-test estandartizado pelo CLSI/NCCLS. RESULTADOS: Os MIC90 (µg/ml de 43 SCoN isolados para fluorquinolonas de segunda geração foram maiores do que os de quarta geração, principalmente para o grupo dos meticilina-resistentes. CONCLUSÃO: Nossos resultados indicam que Staphylococcus coagulase-negativo meticilina-sensíveis são mais suscetíveis às quinolonas do que os Staphylococcus coagulase-negativo meticilina

  13. Expressão de fatores relacionados a células tronco cancerosas e de vasculogênese em cânceres de mama triplo negativos basais e não basais

    OpenAIRE

    Marina De Brot Andrade

    2012-01-01

    Introdução: O câncer de mama triplo negativo é definido pela negatividade para receptores de estrogênio (RE), receptores de progesterona (RP) e receptor do fator de crescimento epidérmico tipo 2 (HER2). O interesse neste tipo de câncer é crescente devido à ausêcia de tratamento sistêmico específico disponível e pela sobreposição com os carcinomas mamários de tipo basal. Embora a maioria destes tumores esteja associada a comportamento biológico agressivo com elevada capacidade metástatica, os ...

  14. Prevalence of Gram-negative Pathogens and their antimicrobial ...

    African Journals Online (AJOL)

    The present study was conducted to find out the prevalence and spectrum of Gram negative pathogens causing bacterial meningitis and their antimicrobial susceptibility pattern in a tertiary care hospital. The cerebrospinal fluid (CSF) (3-5 ml) was collected from 638 admitted children clinically suspected of septic meningitis.

  15. INCREASING PRODUCTION OF PROTEINS IN GRAM-POSITIVE MICROORGANISMS

    NARCIS (Netherlands)

    Quax, Wim; Caldwell, Robert M

    1999-01-01

    The present invention relates to secretion in Gram-positive microorganisms. The present invention provides the nuclei acid and amino acid sequences for the Bacillus subtilis disulfide bond isomerases, Dsb1 and Dsb2. The present invention also provides means for increasing the secretion of

  16. Endocarditis : Effects of routine echocardiography during Gram-positive bacteraemia

    NARCIS (Netherlands)

    Vos, F J; Bleeker-Rovers, C P; Sturm, P D; Krabbe, P F M; van Dijk, A P J; Oyen, W J G; Kullberg, B J

    2011-01-01

    BACKGROUND: Despite firm recommendations to perform echocardiography in high-risk patients with Gram-positive bacteraemia, routine echocardiography is not embedded in daily practice in many settings. The aim of this study was to evaluate whether a regime including routine echocardiography results in

  17. Detection of Extended-Spectrum Β-Lactamases among Gram ...

    African Journals Online (AJOL)

    Biochemical tests confirmed the identity of the Gram-negative isolates to be members of the enterobactericeae, which included Klebsiella pneumoniae (60), Escherichia coli (98), Providencia Spp. (32), Morganella moganii (32), Shigella Spp. (14), Citrobacter freundii (14), Serratia marcescens (10), Salmonella paratyphi A ...

  18. NDM 1 Gene Carrying Gram negative Bacteria Isolated from Rats ...

    African Journals Online (AJOL)

    In this study, we screened 56 Gram negative bacteria comprising: 3 isolates of Enterobacter ludwigii, 30 Pseudomonas aeruginosa, 22 Proteus mirabilis, and 1 Aeromonas caviae isolated from oral cavity and rectum of rats captured from commercial poultry houses in Ibadan, Oyo State, Nigeria that were resistant to at least ...

  19. Diverse Gram-positive bacteria identified from raw and pasteurized ...

    African Journals Online (AJOL)

    Bacterial agents, especially gram-positive bacteria as they are widely distributed in the environment, may contaminate milk all the way from udder of the cow to finished products. This cross-sectional study was carried out from October 2010 to May 2011 on contamination of milk meant for human consumption in Gondar town ...

  20. Diesel degradation and biosurfactant production by Gram-positive ...

    African Journals Online (AJOL)

    The ability of Gram-positive bacteria to degrade diesel increased in a comparable trend as its biosurfactant production increased. The E24 index was highest at 87.6% for isolate D9. Isolates D2, D9 and D10, were identified as Paenibacillus sp. whilst isolate DJLB was found to belong to Stenotrophomonas sp. This study ...

  1. Sinus surgery postpones chronic gram-negative lung infection

    DEFF Research Database (Denmark)

    Alanin, M C; Aanaes, K; Høiby, N

    2016-01-01

    Background: In patients with cystic fibrosis (CF) the sinuses are a bacterial reservoir for Gram-negative bacteria (GNB). From the sinuses the GNB can repeatedly migrate to the lungs. In a one-year follow-up study, endoscopic sinus surgery (ESS) with adjuvant therapy reduced the frequency...

  2. Genetic diversity in green gram accessions as revealed by STMS ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... In this study, 120 accessions of green gram were analysed for 27 Sequence Tagged Microsatellites (STMS) loci. For data analysis, accessions were grouped into Indian and exotic. DNA profiling of the 120 accessions yielded 42 STMS products. The proportion of polymorphic products was 55.56% in Indian.

  3. Diverse Gram-positive bacteria identified from raw and pasteurized ...

    African Journals Online (AJOL)

    Bacterial agents, especially gram-positive bacteria as they are widely distributed in the environment, may ... tices in udder preparation, sub-optimal hygiene of milk handlers, and poor sanita- tion practices associated ... need to maintain appropriate sanitary and hygienic measures at each critical point in order to safeguard ...

  4. Biosorption of mercury by capsulated and slime layer- forming Gram ...

    African Journals Online (AJOL)

    ONOS

    2010-09-20

    Sep 20, 2010 ... The biosorption of mercury by two locally isolated Gram-ve bacilli: Klebsiella pneumoniae ssp. pneumonia (capsulated) and slime layer forming Pseudomonas aeruginosa, was characterized. Mercury adsorption was found to be influenced by the pH value of the biosorption solution, initial metal.

  5. Quinolones resistance and R-plasmids of some gram negative ...

    African Journals Online (AJOL)

    The isolated gram-negative enteric bacilli consist of Escherichia coli (22), Klebsiella species (65), Proteus species (20), Salmonella typhi (2), Pseudomonas aeruginosa (39) and Pseudomonas species (18). Among the antimicrobial agents tested, high resistance was found with ofloxacin 44.0%, followed by pefloxacin 30.1% ...

  6. Biosorption of mercury by capsulated and slime layerforming Gram ...

    African Journals Online (AJOL)

    The biosorption of mercury by two locally isolated Gram-ve bacilli: Klebsiella pneumoniae ssp. pneumonia (capsulated) and slime layer forming Pseudomonas aeruginosa, was characterized. Mercury adsorption was found to be influenced by the pH value of the biosorption solution, initial metal concentration, amount of the ...

  7. Low prevalence of antibiotic-resistant gram-negative bacteria ...

    African Journals Online (AJOL)

    The objective of this study was to determine antibiotic resistance patterns and specific resistance genes in Gram-negative enteric bacteria recovered from 42 different drinking water sources servicing 2 rural villages in south-western Uganda. These water sites were prone to contamination by both human and cattle activity.

  8. Multidrug efflux systems in Gram-negative bacteria

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Scatamburlo Moreira

    2004-06-01

    Full Text Available Multidrug efflux mechanisms in bacteria contribute significantly to intrinsic and acquired resistance to antimicrobial agents. Genome analysis have confirmed the broad distribution of these systems in Gram-negative as well as in Gram-positive bacteria. Among resistance mechanisms, the multidrug efflux system or pump deserves special attention, since a cell that has acquired it can simultaneously diminish or even suppress the susceptibility to a wide range of antimicrobials. The efflux system is mediated by transport proteins which confer resistance to toxic compounds. In Gram-negative bacteria, a tripartite efflux system is necessary to expel the drug to the outer medium: a protein localized in the cytoplasmic membrane; another in the periplasmatic space (membrane fusion protein - MFP; and a third in the outer membrane (outer membrane factor - OMF. The drug transport is active, and depends either on the energy provided by ATP hydrolysis or is directly driven by the proton motive force. The transport proteins are grouped in families, according to the homology of the amino acid sequences and to similarity of mechanisms. Among Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa have most of the hitherto identified and studied multidrug efflux systems.

  9. Occurrence of unusual non-fermentative gram negative bacilli in ...

    African Journals Online (AJOL)

    Non-fermentative Gram-negative bacilli (NFGNB) other than Pseudomonas and Acinetobacter species have emerged as nosocomial pathogens. No much data is currently available concerning the occurrence of these types of bacteria in Zagazig University Hospitals (ZUHs). In this study, the occurrence as well as the ...

  10. Genetic diversity in green gram [Vigna radiata (L.)] landraces ...

    African Journals Online (AJOL)

    Green gram [Vigna radiata (L.)] landraces were collected from various localities of Southern Tamil Nadu, India, to determine the extent of genetic diversity at DNA level by random amplified polymorphic DNA (RAPD) analysis using 20 decamer primers. All the primers produced polymorphic amplification products with some ...

  11. Defining a role for Hfq in Gram-positive bacteria

    DEFF Research Database (Denmark)

    Nielsen, Jesper Sejrup; Lei, Lisbeth Kristensen; Ebersbach, Tine

    2010-01-01

    Small trans-encoded RNAs (sRNAs) modulate the translation and decay of mRNAs in bacteria. In Gram-negative species, antisense regulation by trans-encoded sRNAs relies on the Sm-like protein Hfq. In contrast to this, Hfq is dispensable for sRNA-mediated riboregulation in the Gram-positive species...... studied thus far. Here, we provide evidence for Hfq-dependent translational repression in the Gram-positive human pathogen Listeria monocytogenes, which is known to encode at least 50 sRNAs. We show that the Hfq-binding sRNA LhrA controls the translation and degradation of its target mRNA by an antisense...... mechanism, and that Hfq facilitates the binding of LhrA to its target. The work presented here provides the first experimental evidence for Hfq-dependent riboregulation in a Gram-positive bacterium. Our findings indicate that modulation of translation by trans-encoded sRNAs may occur by both Hfq...

  12. Authorship Attribution with Function Word N-Grams

    Science.gov (United States)

    Johnson, Rusty

    2013-01-01

    Prior research has considered the sequential order of function words, after the contextual words of the text have been removed, as a stylistic indicator of authorship. This research describes an effort to enhance authorship attribution accuracy based on this same information source with alternate classifiers, alternate n-gram construction methods,…

  13. Detection of Extended Spectrum Beta-Lactamases in Gram Negative ...

    African Journals Online (AJOL)

    Antimicrobial drug resistance seen among many gram-negative bacteria, especially those expressing the extended-spectrum β-lactamase (ESBL) enzymes that hydrolyze the expandedspectrum cephalosporins has been on the increase. This has compromised treatment options and thus a threat to the containment of ...

  14. Um protótipo de gramática gerativa portuguesa: a gramática de Soares Barbosa

    Directory of Open Access Journals (Sweden)

    Edward Lopes

    2001-01-01

    Full Text Available

    Este trabalho estuda os aspectos doutrinários da Grammatica Philosophica da Lingua Portugueza, de Jerônimo Soares Barbosa, elaborada com base na doutrina da Grammaire générale et raisonnée de Port-Royal, para mostrar que ela é o protótipo iluminista de uma gramática gerativa da língua portuguesa. Essa gramática é a expressão das idéias iluministas no domínio da ciência da linguagem. Insere-se assim no embate ideológico que se travava, nessa época, entre as idéias absolutistas e a filosofia das Luzes. Essas posições manifestam-se, no nível dos estudos lingüísticos, pela gramática normativa, que estabelece um saber fazer, e pela gramática filosófica, que constrói um fazer.

  15. Antimicrobial Activities of Leaf Extracts of Guava (Psidium guajava L.) on Two Gram-Negative and Gram-Positive Bacteria

    Science.gov (United States)

    Biswas, Bipul; Rogers, Kimberly; McLaughlin, Fredrick; Yadav, Anand

    2013-01-01

    Aim. To determine the antimicrobial potential of guava (Psidium guajava) leaf extracts against two gram-negative bacteria (Escherichia coli and Salmonella enteritidis) and two gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) which are some of foodborne and spoilage bacteria. The guava leaves were extracted in four different solvents of increasing polarities (hexane, methanol, ethanol, and water). The efficacy of these extracts was tested against those bacteria through a well-diffusion method employing 50 μL leaf-extract solution per well. According to the findings of the antibacterial assay, the methanol and ethanol extracts of the guava leaves showed inhibitory activity against gram-positive bacteria, whereas the gram-negative bacteria were resistant to all the solvent extracts. The methanol extract had an antibacterial activity with mean zones of inhibition of 8.27 and 12.3 mm, and the ethanol extract had a mean zone of inhibition of 6.11 and 11.0 mm against B. cereus and S. aureus, respectively. On the basis of the present finding, guava leaf-extract might be a good candidate in the search for a natural antimicrobial agent. This study provides scientific understanding to further determine the antimicrobial values and investigate other pharmacological properties. PMID:24223039

  16. Antimicrobial Activities of Leaf Extracts of Guava (Psidium guajava L.) on Two Gram-Negative and Gram-Positive Bacteria.

    Science.gov (United States)

    Biswas, Bipul; Rogers, Kimberly; McLaughlin, Fredrick; Daniels, Dwayne; Yadav, Anand

    2013-01-01

    Aim. To determine the antimicrobial potential of guava (Psidium guajava) leaf extracts against two gram-negative bacteria (Escherichia coli and Salmonella enteritidis) and two gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) which are some of foodborne and spoilage bacteria. The guava leaves were extracted in four different solvents of increasing polarities (hexane, methanol, ethanol, and water). The efficacy of these extracts was tested against those bacteria through a well-diffusion method employing 50  μ L leaf-extract solution per well. According to the findings of the antibacterial assay, the methanol and ethanol extracts of the guava leaves showed inhibitory activity against gram-positive bacteria, whereas the gram-negative bacteria were resistant to all the solvent extracts. The methanol extract had an antibacterial activity with mean zones of inhibition of 8.27 and 12.3 mm, and the ethanol extract had a mean zone of inhibition of 6.11 and 11.0 mm against B. cereus and S. aureus, respectively. On the basis of the present finding, guava leaf-extract might be a good candidate in the search for a natural antimicrobial agent. This study provides scientific understanding to further determine the antimicrobial values and investigate other pharmacological properties.

  17. Top-Down LESA Mass Spectrometry Protein Analysis of Gram-Positive and Gram-Negative Bacteria

    Science.gov (United States)

    Kocurek, Klaudia I.; Stones, Leanne; Bunch, Josephine; May, Robin C.; Cooper, Helen J.

    2017-10-01

    We have previously shown that liquid extraction surface analysis (LESA) mass spectrometry (MS) is a technique suitable for the top-down analysis of proteins directly from intact colonies of the Gram-negative bacterium Escherichia coli K-12. Here we extend the application of LESA MS to Gram-negative Pseudomonas aeruginosa PS1054 and Gram-positive Staphylococcus aureus MSSA476, as well as two strains of E. coli (K-12 and BL21 mCherry) and an unknown species of Staphylococcus. Moreover, we demonstrate the discrimination between three species of Gram-positive Streptococcus ( Streptococcus pneumoniae D39, and the viridans group Streptococcus oralis ATCC 35037 and Streptococcus gordonii ATCC35105), a recognized challenge for matrix-assisted laser desorption ionization time-of-flight MS. A range of the proteins detected were selected for top-down LESA MS/MS. Thirty-nine proteins were identified by top-down LESA MS/MS, including 16 proteins that have not previously been observed by any other technique. The potential of LESA MS for classification and characterization of novel species is illustrated by the de novo sequencing of a new protein from the unknown species of Staphylococcus. [Figure not available: see fulltext.

  18. How bacterial cell division might cheat turgor pressure - a unified mechanism of septal division in Gram-positive and Gram-negative bacteria.

    Science.gov (United States)

    Erickson, Harold P

    2017-08-01

    An important question for bacterial cell division is how the invaginating septum can overcome the turgor force generated by the high osmolarity of the cytoplasm. I suggest that it may not need to. Several studies in Gram-negative bacteria have shown that the periplasm is isoosmolar with the cytoplasm. Indirect evidence suggests that this is also true for Gram-positive bacteria. In this case the invagination of the septum takes place within the uniformly high osmotic pressure environment, and does not have to fight turgor pressure. A related question is how the V-shaped constriction of Gram-negative bacteria relates to the plate-like septum of Gram-positive bacteria. I collected evidence that Gram-negative bacteria have a latent capability of forming plate-like septa, and present a model in which septal division is the basic mechanism in both Gram-positive and Gram-negative bacteria. © 2017 WILEY Periodicals, Inc.

  19. La Gramática Discursivo-Funcional

    NARCIS (Netherlands)

    Hengeveld, K.; Mackenzie, J.L.

    2011-01-01

    La Gramática Discursivo-Funcional (GDF) es una teoría funcional del lenguaje de inspiración tipológica que presenta una organización descendente (top-down) con el objeto de alcanzar la adecuación psicológica y que toma el Acto Discursivo como unidad básica de análisis para lograr la adecuación

  20. Current and novel antibiotics against resistant Gram-positive bacteria

    OpenAIRE

    Perez, Federico; Salata, Robert A; Bonomo, Robert A

    2008-01-01

    The challenge posed by resistance among Gram-positive bacteria, epitomized by methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE) and vancomycin-intermediate and -resistant S. aureus (VISA and VRSA) is being met by a new generation of antimicrobials. This review focuses on the new β-lactams with activity against MRSA (ceftobiprole and ceftaroline) and on the new glycopeptides (oritavancin, dalbavancin, and telavancin). It will also consider the role of ...

  1. Current and novel antibiotics against resistant Gram-positive bacteria

    OpenAIRE

    Perez, Federico

    2008-01-01

    Federico Perez1, Robert A Salata1, Robert A Bonomo21Division of Infectious Diseases and HIV Medicine, University Hospitals Case Medical Center, Cleveland OH, USA; 2Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, USAAbstract: The challenge posed by resistance among Gram-positive bacteria, epitomized by methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE) and vancomycin-intermediate and -resis...

  2. GramCheck: A Grammar and Style Checker

    OpenAIRE

    Bustamante, Flora Ramírez; León, Fernando Sánchez

    1996-01-01

    This paper presents a grammar and style checker demonstrator for Spanish and Greek native writers developed within the project GramCheck. Besides a brief grammar error typology for Spanish, a linguistically motivated approach to detection and diagnosis is presented, based on the generalized use of PROLOG extensions to highly typed unification-based grammars. The demonstrator, currently including full coverage for agreement errors and certain head-argument relation issues, also provides correc...

  3. Hyperorthogonal family of vectors and the associated Gram matrix

    DEFF Research Database (Denmark)

    Fuglede, Bent

    2014-01-01

    A family of non-zero vectors in Euclidean n -space is termed hyperorthogonal if the angle between any two distinct vectors of the family is at least π/2 . Any hyperorthogonal family is finite and contains at most 2n vectors. It decomposes uniquely into the union of mutually orthogonal irreducible...... subfamilies. An equivalent formulation in terms of the associated Gram matrix is given....

  4. Antimicrobial activity of metal oxide nanoparticles against Gram-positive and Gram-negative bacteria: a comparative study

    Directory of Open Access Journals (Sweden)

    Azam A

    2012-12-01

    Full Text Available Ameer Azam,1,2 Arham S Ahmed,2 Mohammad Oves,3 Mohammad S Khan,3 Sami S Habib,1 Adnan Memic11Centre of Nanotechnology, King Abdulaziz University, Jeddah, Saudi Arabia; 2Centre of Excellence in Materials Science (Nanomaterials, 3Department of Agricultural Microbiology, Aligarh Muslim University, Aligarh, IndiaBackground: Nanomaterials have unique properties compared to their bulk counterparts. For this reason, nanotechnology has attracted a great deal of attention from the scientific community. Metal oxide nanomaterials like ZnO and CuO have been used industrially for several purposes, including cosmetics, paints, plastics, and textiles. A common feature that these nanoparticles exhibit is their antimicrobial behavior against pathogenic bacteria. In this report, we demonstrate the antimicrobial activity of ZnO, CuO, and Fe2O3 nanoparticles against Gram-positive and Gram-negative bacteria.Methods and results: Nanosized particles of three metal oxides (ZnO, CuO, and Fe2O3 were synthesized by a sol–gel combustion route and characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, and transmission electron microscopy techniques. X-ray diffraction results confirmed the single-phase formation of all three nanomaterials. The particle sizes were observed to be 18, 22, and 28 nm for ZnO, CuO, and Fe2O3, respectively. We used these nanomaterials to evaluate their antibacterial activity against both Gram-negative (Escherichia coli and Pseudomonas aeruginosa and Gram-positive (Staphylococcus aureus and Bacillus subtilis bacteria.Conclusion: Among the three metal oxide nanomaterials, ZnO showed greatest antimicrobial activity against both Gram-positive and Gram-negative bacteria used in this study. It was observed that ZnO nanoparticles have excellent bactericidal potential, while Fe2O3 nanoparticles exhibited the least bactericidal activity. The order of antibacterial activity was demonstrated to be the following: ZnO > CuO > Fe2O3

  5. Keywords in Context (Using n-grams with Python

    Directory of Open Access Journals (Sweden)

    William J. Turkel

    2012-07-01

    Full Text Available Like in Output Data as HTML File, this lesson takes the frequency pairs collected in Counting Frequencies and outputs them in HTML. This time the focus is on keywords in context (KWIC which creates n-grams from the original document content – in this case a trial transcript from the Old Bailey Online. You can use your program to select a keyword and the computer will output all instances of that keyword, along with the words to the left and right of it, making it easy to see at a glance how the keyword is used. Once the KWICs have been created, they are then wrapped in HTML and sent to the browser where they can be viewed. This reinforces what was learned in Output Data as HTML File, opting for a slightly different output. At the end of this lesson, you will be able to extract all possible n-grams from the text. In the next lesson, you will be learn how to output all of the n-grams of a given keyword in a document downloaded from the Internet, and display them clearly in your browser window.

  6. Amplifiable DNA from Gram-negative and Gram-positive bacteria by a low strength pulsed electric field method

    Science.gov (United States)

    Vitzthum, Frank; Geiger, Georg; Bisswanger, Hans; Elkine, Bentsian; Brunner, Herwig; Bernhagen, Jürgen

    2000-01-01

    An efficient electric field-based procedure for cell disruption and DNA isolation is described. Isoosmotic suspensions of Gram-negative and Gram-positive bacteria were treated with pulsed electric fields of Pulses had an exponential decay waveform with a time constant of 3.4 µs. DNA yield was linearly dependent on time or pulse number, with several thousand pulses needed. Electrochemical side-effects and electrophoresis were minimal. The lysates contained non-fragmented DNA which was readily amplifiable by PCR. As the method was not limited to samples of high specific resistance, it should be applicable to physiological fluids and be useful for genomic and DNA diagnostic applications. PMID:10734214

  7. Organo-Selenium Coatings Inhibit Gram-Negative and Gram-Positive Bacterial Attachment to Ophthalmic Scleral Buckle Material.

    Science.gov (United States)

    Tran, Phat; Arnett, Avery; Jarvis, Courtney; Mosley, Thomas; Tran, Khien; Hanes, Rob; Webster, Dan; Mitchell, Kelly; Dominguez, Leo; Hamood, Abdul; Reid, Ted W

    2017-09-01

    Biofilm formation is a problem for solid and sponge-type scleral buckles. This can lead to complications that require removal of the buckle, and result in vision loss due to related ocular morbidity, primarily infection, or recurrent retinal detachment. We investigate the ability of a covalent organo-selenium coating to inhibit biofilm formation on a scleral buckle. Sponge and solid Labtican brand scleral buckles were coated with organo-selenium coupled to a silyation reagent. Staphylococcus aureus biofilm formation was monitored by a standard colony-forming unit assay and the confocal laser scanning microscopy, while Pseudomonas aeruginosa biofilm formation was examined by scanning electron microscopy. Stability studies were done, by soaking in phosphate buffer saline (PBS) at room temperature for 2 months. Toxicity against human corneal epithelial cell was examined by growing the cells in the presence of organo-selenium-coated scleral buckles. The organo-selenium coating inhibited biofilm formation by gram-negative and gram-positive bacteria. The buckle coatings also were shown to be fully active after soaking in PBS for 2 months. The organo-selenium coatings had no effect on the viability of human corneal epithelial cells. Organo-selenium can be used to covalently coat a scleral buckle, which is stable and inhibits biofilm formation for gram-negative and gram-positive bacteria. The organo-selenium buckle coating was stable and nontoxic to cell culture. This technology provides a means to inhibit bacterial attachment to devices attached to the eye, without damage to ocular cells.

  8. Antibacterial Activity of Stenotrophomonas maltophilia Endolysin P28 against both Gram-positive and Gram-negative Bacteria.

    Science.gov (United States)

    Dong, Hongling; Zhu, Chaoyang; Chen, Jingyi; Ye, Xing; Huang, Yu-Ping

    2015-01-01

    Maltocin P28 is a phage-tail like bacteriocin produced by Stenotrophomonas maltophilia P28. The ORF8 of maltocin P28 gene cluster is predicted to encode an endolysin and we name it endolysin P28. Sequence analysis revealed that it contains the lysozyme_like superfamily conserved domain. Endolysin P28 has the four consensus motifs as that of Escherichia coli phage lambda gpR. In this study, endolysin P28 was expressed in E. coli BL21 (DE3) and purified with a C-terminal oligo-histidine tag. The antibacterial activity of endolysin P28 increased as the temperature rose from 25 to 45°C. Thermostability assays showed that endolysin P28 was stable up to 50°C, while its residual activity was reduced by 55% after treatment at 70°C for 30 min. Acidity and high salinity could enhance its antibacterial activity. Endolysin P28 exhibited a broad antibacterial activity against 14 out of 16 tested Gram-positive and Gram-negative bacteria besides S. maltophilia. Moreover, it could effectively lyse intact Gram-negative bacteria in the absence of ethylenediaminetetraacetic acid as an outer membrane permeabilizer. Therefore, the characteristics of endolysin P28 make it a potential therapeutic agent against multi-drug-resistant pathogens.

  9. Antibacterial activity of Stenotrophomonas maltophilia endolysin P28 against both Gram-positive and Gram-negative bacteria

    Directory of Open Access Journals (Sweden)

    Hongling eDong

    2015-11-01

    Full Text Available Maltocin P28 is a phage-tail like bacteriocin produced by Stenotrophomonas maltophilia P28. The ORF8 of maltocin P28 gene cluster is predicted to encode an endolysin and we name it endolysin P28. Sequence analysis revealed that it contains the lysozyme_like superfamily conserved domain. Endolysin P28 has the four consensus motifs as that of Escherichia coli phage lambda gpR. In this study endolysin P28 was expressed in E. coli BL21 (DE3 and purified with a C-terminal oligo-histidine tag. The antibacterial activity of endolysin P28 increased as the temperature rose from 25°C to 45°C. Thermostability assays showed that endolysin P28 was stable up to 50°C, while its residual activity was reduced by 55% after treatment at 70°C for 30 min. Acidity and high salinity could enhance its antibacterial activity. Endolysin P28 exhibited a broad antibacterial activity against 14 out of 16 tested Gram-positive and Gram-negative bacteria besides S. maltophilia. Moreover, it could effectively lyse intact Gram-negative bacteria in the absence of ethylenediaminetetraacetic acid (EDTA as an outer membrane permeabilizer. Therefore, the characteristics of endolysin P28 make it a potential therapeutic agent against multi-drug-resistant pathogens.

  10. Characterizing the Behavior of a Program Using Multiple-Length N-Grams

    National Research Council Canada - National Science Library

    Marceau, Carla

    2005-01-01

    ...) of those traces are called N-grams. The set of N-grams occurring during normal execution has been found to discriminate effectively between normal behavior of a program and the behavior of the program under attack...

  11. A new bacterial staining method involving Gram stain with theoretical considerations of the staining mechanism.

    Science.gov (United States)

    Noda, Y; Tôei, K

    1992-01-01

    In order to investigate the mechanism of Gram staining of bacteria, tests with anionic dyes followed by treatment with cationic octyltrimethylammonium (OTMA) were carried out. The study revealed that tetrabromophenolphthalein ethylester (TBPE) gave the most reliable staining of Gram-negative bacteria with negative staining of Gram-positive bacteria. Tests on many species of bacteria showed that TBPE positive bacteria were Gram-negative and vice versa, without exception.

  12. Uso do contraste oral negativo em exames de colangiografia por ressonância magnética Use of oral negative contrast agent in magnetic resonance cholangiopancreatography examinations

    Directory of Open Access Journals (Sweden)

    Mário de Melo Galvão Filho

    2002-10-01

    Full Text Available OBJETIVO: Realizamos estudo prospectivo das vias biliares e pancreáticas através de colangiografia por ressonância magnética, com a utilização de meio de contraste oral negativo. Os nossos objetivos foram verificar se este novo meio de contraste melhora a visualização das vias biliar e pancreática, além de identificar a freqüência de efeitos colaterais ao contraste e sua aceitação pelo paciente. MATERIAL E MÉTODO: Quinze voluntários (oito homens e sete mulheres com idades variando entre 18 e 54 anos (média de 29 anos, sem queixas ou cirurgias abdominais, foram submetidos a colangiografia por ressonância magnética. Foram realizadas duas seqüências colangiográficas em apnéia, antes e cinco minutos após a ingestão de 300 ml de contraste oral negativo. Os exames foram realizados em equipamento operando a 1,0 T. RESULTADOS: Setenta e três por cento dos voluntários consideraram o gosto ruim ou muito ruim, sugerindo uma aceitação discutível; 27% dos voluntários apresentaram náuseas; 20%, cólicas; 14%, azia ou parestesia labial; e 7%, diarréia. A visualização da via biliar extra-hepática foi considerada melhor após o contraste oral negativo em 9/15 voluntários (60% e do ducto pancreático principal em todos os cinco em que havia interposição de alças. CONCLUSÃO: O contraste oral negativo melhora a visualização dos ductos hepatocolédoco e pancreático principal em exames de colangiografia por ressonância magnética, apesar da baixa aceitação e dos seus efeitos colaterais.OBJECTIVE: The aim of this prospective study was to investigate the feasibility of using a negative oral contrast agent to null the bowel signal during magnetic resonance cholangiopancreatography. MATERIAL AND METHOD: Fifteen healthy volunteers with no previous history of pancreaticobiliary disease or surgery were imaged with a single-shot fast spin-echo pulse sequence, using a magnetic resonance imaging system operating at 1.0 T. Data

  13. Prevalencia de microorganismos causantes de bacteriemias y fungemias en pacientes oncológicos pediátricos: Patrones de sensibilidad a los antimicrobianos Prevalence and antimicrobial susceptibility patterns of microorganisms causing bacteremia and fungemia in pediatric oncology patients

    Directory of Open Access Journals (Sweden)

    M. L. Cheguirián

    2008-06-01

    Full Text Available El objetivo del presente trabajo fue conocer la distribución y frecuencia de los microorganismos causantes de bacteriemias y fungemias en los pacientes oncológicos internados en el Hospital de Niños de Córdoba, así como describir sus patrones de sensibilidad a los antimicrobianos. Se estudiaron 59 episodios de bacteriemias y fungemias ocurridos entre enero de 2006 y abril de 2007 en 44 pacientes. Del total de los aislamientos recuperados, el 45,8% fueron bacilos gram-negativos, el 35,6% cocos gram-positivos y el 18,6% levaduras. La distribución global de los microorganismos más prevalentes fue: Klebsiella spp. 15,3%; Staphylococcus aureus 11,9%; Candida parapsilosis 11,9%; estafilococos coagulasa negativos 10,2%; Escherichia coli 8,5% y Pseudomonas aeruginosa 6,8%. El 41,2% de las enterobacterias aisladas presentó un fenotipo compatible con la presencia de alguna b-lactamasa de espectro extendido, y el 20,0% de los bacilos gram-negativos no fermentadores presentó multirresistencia a los antibióticos ensayados. En cuanto a los cocos gram-positivos, el 38,5% de los Staphylococcus spp. fue resistente a meticilina. Se puede concluir que los microorganismos más prevalentes en la población estudiada fueron los bacilos gram-negativos; dentro de este grupo las enterobacterias fueron las que presentaron mayor porcentaje de resistencia a los antibióticos ensayados.The purpose of our research was to know the frequency of microorganisms causing bacteremia and/or fungemia in oncology patients from Hospital de Niños de Córdoba, as well as to describe the antimicrobial susceptibility patterns of bacteria isolated from January 2006 to April 2007. A total of 59 bacteremia and fungemia cases in 44 patients were studied. From the total number of isolations, 45.8% were gram-negative bacilli, 35.6% were gram-positive cocci, and 18.6% were yeasts. The global distribution of the most prevalent microorganisms was the following: Klebsiella spp. 15

  14. Rapid discrimination of Gram-positive and Gram-negative bacteria in liquid samples by using NaOH-sodium dodecyl sulfate solution and flow cytometry.

    Directory of Open Access Journals (Sweden)

    Atsushi Wada

    Full Text Available BACKGROUND: For precise diagnosis of urinary tract infections (UTI, and selection of the appropriate prescriptions for their treatment, we explored a simple and rapid method of discriminating gram-positive and gram-negative bacteria in liquid samples. METHODOLOGY/PRINCIPAL FINDINGS: We employed the NaOH-sodium dodecyl sulfate (SDS solution conventionally used for plasmid extraction from Escherichia coli and the automated urine particle analyzer UF-1000i (Sysmex Corporation for our novel method. The NaOH-SDS solution was used to determine differences in the cell wall structures between gram-positive and gram-negative bacteria, since the tolerance to such chemicals reflects the thickness and structural differences of bacterial cell walls. The UF-1000i instrument was used as a quantitative bacterial counter. We found that gram-negative bacteria, including E. coli, in liquid culture could easily be lysed by direct addition of equal volumes of NaOH-SDS solution. In contrast, Enterococcus faecalis, which is a gram-positive bacterium, could not be completely lysed by the solution. We then optimized the reaction time of the NaOH-SDS treatment at room temperature by using 3 gram-positive and 4 gram-negative bacterial strains and determined that the optimum reaction time was 5 min. Finally, in order to evaluate the generalizability of this method, we treated 8 gram-positive strains and 8 gram-negative strains, or 4 gram-positive and 4 gram-negative strains incubated in voluntary urine from healthy volunteers in the same way and demonstrated that all the gram-positive bacteria were discriminated quantitatively from gram negative bacteria using this method. CONCLUSIONS/SIGNIFICANCE: Using our new method, we could easily discriminate gram-positive and gram-negative bacteria in liquid culture media within 10 min. This simple and rapid method may be useful for determining the treatment course of patients with UTIs, especially for those without a prior history

  15. GRAM 88 - 4D GLOBAL REFERENCE ATMOSPHERE MODEL-1988

    Science.gov (United States)

    Johnson, D. L.

    1994-01-01

    The Four-D Global Reference Atmosphere program was developed from an empirical atmospheric model which generates values for pressure, density, temperature, and winds from surface level to orbital altitudes. This program can generate altitude profiles of atmospheric parameters along any simulated trajectory through the atmosphere. The program was developed for design applications in the Space Shuttle program, such as the simulation of external tank re-entry trajectories. Other potential applications are global circulation and diffusion studies; also the generation of profiles for comparison with other atmospheric measurement techniques such as satellite measured temperature profiles and infrasonic measurement of wind profiles. GRAM-88 is the latest version of the software GRAM. The software GRAM-88 contains a number of changes that have improved the model statistics, in particular, the small scale density perturbation statistics. It also corrected a low latitude grid problem as well as the SCIDAT data base. Furthermore, GRAM-88 now uses the U.S. Standard Atmosphere 1976 as a comparison standard rather than the US62 used in other versions. The program is an amalgamation of two empirical atmospheric models for the low (25km) and the high (90km) atmosphere, with a newly developed latitude-longitude dependent model for the middle atmosphere. The Jacchia (1970) model simulates the high atmospheric region above 115km. The Jacchia program sections are in separate subroutines so that other thermosphericexospheric models could easily be adapted if required for special applications. The improved code eliminated the calculation of geostrophic winds above 125 km altitude from the model. The atmospheric region between 30km and 90km is simulated by a latitude-longitude dependent empirical model modification of the latitude dependent empirical model of Groves (1971). A fairing technique between 90km and 115km accomplished a smooth transition between the modified Groves values and

  16. Is the gram stain useful in the microbiologic diagnosis of VAP? A meta-analysis.

    Science.gov (United States)

    O'Horo, John C; Thompson, Deb; Safdar, Nasia

    2012-08-01

    In a meta-analysis examining respiratory specimen Gram stain for diagnosis of ventilator-associated pneumonia, absence of bacteria on Gram stain had a high negative predictive value, but a positive Gram stain correlated poorly with organisms recovered in culture. Rapid and accurate diagnosis of ventilator-associated pneumonia (VAP) is a major challenge and no generally accepted gold standard exists for VAP diagnosis. We conducted a meta-analysis to examine the role of respiratory specimen Gram stain to diagnose VAP, and the correlation with final culture results. In 21 studies, pooled sensitivity of Gram stain for VAP was 0.79 (95% confidence interval [CI], .77-0.81; P Gram stain for a VAP prevalence of 20%-30% was 91%, suggesting that VAP is unlikely with a negative Gram stain but the positive predictive value of Gram stain was only 40%. Pooled kappa was 0.42 for gram-positive organisms and 0.34 for gram-negative organisms, suggesting fair concordance between organisms on Gram stain and recovery by culture. Therefore, a positive Gram stain should not be used to narrow anti-infective therapy until culture results become available.

  17. 78 FR 18352 - Determination That QUESTRAN (Cholestyramine for Oral Suspension, USP), Equivalent to 4 Grams, and...

    Science.gov (United States)

    2013-03-26

    ...] Determination That QUESTRAN (Cholestyramine for Oral Suspension, USP), Equivalent to 4 Grams, and QUESTRAN LIGHT (Cholestyramine for Oral Suspension, USP), Equivalent to 4 Grams, Were Not Withdrawn From Sale for Reasons of...), equivalent to (EQ) 4 grams (g), and QUESTRAN LIGHT (cholestyramine for oral suspension, USP), EQ 4 g, were...

  18. Prevalência de sepse por bactérias Gram negativas produtoras de beta-lactamase de espectro estendido em Unidade de Cuidados Intensivos Neonatal Prevalence of extended-spectrum beta-lactamase producing Gram-negative bacterial sepsis in a Neonatal Intensive Care Unit

    Directory of Open Access Journals (Sweden)

    Carla Regina Tragante

    2008-03-01

    Full Text Available OBJETIVO: Determinar a prevalência e a mortalidade de sepse neonatal por bactérias Gram negativas produtoras de beta-lactamase de espectro estendido (ESBL em Unidade de Cuidados Intensivos Neonatal. MÉTODOS: Trata-se de um estudo retrospectivo e descritivo de 236 recém-nascidos com suspeita de sepse entre 2000 e 2004. O diagnóstico de sepse foi confirmado pela presença de sinais clínicos associada à positividade da hemocultura. A triagem para bactérias ESBL foi realizada segundo os critérios do National Committee for Clinical Laboratory Standards. RESULTADOS: 84 (36% recém-nascidos apresentaram hemocultura positiva, sendo a Klebsiella pneumoniae o agente mais prevalente (47%. A análise dos neonatos com infecção por Klebsiella pneumoniae mostrou que sete destas eram ESBL, perfazendo uma taxa de infecção de 0,4%. Todos os recém-nascidos com Klebsiella pneumoniae ESBL - exceto um - foram hospitalizados por mais de 21 dias e necessitaram de ventilação mecânica; todos tinham cateter central, nutrição parenteral e antibióticos de largo espectro. A mortalidade ocorreu em 36 (43% dos 84 neonatos com sepse confirmada. Dentre os óbitos, as hemoculturas mostraram Gram negativos (67% e fungos (19%. Em relação à Klebsiella pneumoniae ESBL, três recém-nascidos (43% morreram. CONCLUSÕES: A prevalência de sepse por Klebsiella pneumoniae ESBL no período do estudo foi de 0,4% e a mortalidade de 43%. É importante a detecção e o controle da disseminação deste tipo de microrganismo por seu impacto negativo na sobrevida de recém-nascidos prematuros e/ou doentes.OBJECTIVE: To determine the neonatal sepsis prevalence and the mortality of extended-spectrum beta-lactamase producing Gram-negative bacteria (ESBL in a Neonatal Intensive Care Unit. METHODS: This is a descriptive and retrospective study of 236 newborn infants with sepsis suspicion from 2000 to 2004. The diagnosis was confirmed by clinical signs and positive blood culture

  19. [Diagnostic and therapeutic management of Gram-negative infections].

    Science.gov (United States)

    Bassetti, Matteo; Repetto, Ernestina

    2008-04-01

    Among Gram negative bacteria, Pseudomonas aeruginosa, the extended spectrum beta-lactamases (ESBL)-producing strains, Acinetobacter spp, in particular the multiresistant Acinetobacter baumannii, and Stenotrophomonas maltophilia are the most implicated micrororganisms in the ever more increasing problem of bacterial resistance. Possible solutions have to be searched, on one hand, in the use of new drugs but, on the other hand, in the re-evaluation of those already available drugs, possibly considering a new role for old drugs such as colistine and fosfomycin. Concerning ESBL-producing strains, the most recent data provided by EARSS report, in Italy, an incidence rate of 10-25 percent. The insurgence of an infection sustained by an ESBL+ve strain is strictly related to some well known risk factors, like the hospital stay itself, the disease severity, the length of stay in ICU, intubation and mechanical ventilation, catheterization, urinary or artery, and the past exposure to antibiotics. The raise in ESBL producing strains is closely related to the increasing use of cephalosporins. In the setting of a Gram negative infection, the combination therapy guarantees a higher coverage by reducing insurgence of possible resistance mechanisms, possibly resulting synergistic, and allowing a de-escalation therapy, although to this latter other problems, such as tolerability, costs and compliance, can be related. Another basic aspect to take into account of, in order to achieve the maximal efficacy of the antibiotic treatment, is the right dosage. In the idea to look for the best approach for the antibiotic treatment of a severe infection in a hospital setting, when a Gram negative aetiology is implicated, it can be possibly presumed that the right way consists in avoiding inappropriate antibiotic therapies, making therapeutic choices based on guidelines resulted from local epidemiological data, initiating the therapy promptly, avoiding excessive use of antibiotics, possibly

  20. Novel pharmaceutical molecules against emerging resistant gram-positive cocci

    Directory of Open Access Journals (Sweden)

    Roberto Manfredi

    Full Text Available INTRODUCTION: methicillin- and also vancomycin (glycopeptide-resistant Gram-positive organisms have emerged as an increasingly problematic cause of hospital-acquired infections, also spreading into the community. Vancomycin (glycopeptide resistance has emerged primarily among Enterococci, but the MIC values of vancomycin for the entire Staphylococcus species are also increasing worldwide. MATERIAL AND METHODS: the aim of our review is to evaluate the efficacy and tolerability of newer antibiotics with activity against methicillin-resistant and glycopeptide-resistant Gram-positive cocci, on the ground of our experience at a tertiary care metropolitan Hospital, and the most recent literature evidences in this field. RESULTS: Quinupristin-dalfopristin, linezolid, daptomycin, and tigecycline show an excellent in vitro activity, comparable to the activity of vancomycin and teicoplanin for methicillin-resistant staphylococci, and superior to the one that vancomycin for vancomycin-resistant isolates. Dalbavancin, televancin, and oritavancin are new lipoglycopeptide agents with excellent activity against Gram-positive cocci, and have superior pharmacodynamics properties compared to vancomycin. We review the bacterial spectrum, clinical indications and practical use, pharmacologic properties, and expected adverse events and contraindications associated with each of these novel antimicrobial agents, compared with the present standard of care. DISCUSSION: linezolid activity is substantially comparable to that of vancomycin in patients with methicillin-resistant Staphylococcus aureus (MRSA pneumonia, although its penetration into the respiratory tract is exceptionally elevated. Tigecycline has activity against both Enterococus species and MRSA; it is also active against a broad spectrum of Enterobacteriaceae and anaerobes, which allows for use intraabdominal, diabetic foot and surgical infections. Daptomycin has a rapid bactericidal activity for

  1. Paracoccus marcusii sp. nov., an orange gram-negative coccus.

    Science.gov (United States)

    Harker, M; Hirschberg, J; Oren, A

    1998-04-01

    Phenotypic, chemotaxonomic and 16S rDNA sequence analysis of an orange Gram-negative coccus that appeared as a contaminant on a nutrient agar plate delineated a new species of the genus Paracoccus. Phenotypic features of the strain that differ from all or most of the previously described Paracoccus species include its bright orange colour, caused by the synthesis of large amounts of carotenoids (mainly astaxanthin), and its inability to use nitrate as an electron acceptor in respiration. The name Paracoccus marcusii is proposed for this organism. The type strain is DSM 11574T.

  2. Studies on reproductive stress caused by candidate Gram positive and Gram negative bacteria using model organism, Caenorhabditis elegans.

    Science.gov (United States)

    Sharika, Rajasekharan; Subbaiah, Priya; Balamurugan, Krishnaswamy

    2018-04-05

    Microbial association with a host using model system C. elegans have been widely studied based on factors such as host survival, the mode of infection, disease pathogenesis and the role of various players regulated during infection. The influence of pathogenic microorganism on reproduction and associated issues has not been explored fully. The present study focuses on the impact of bacterial infection on male reproductive parameters such as spermatogenesis and spermiogenesis, including physiological aspects like tail morphology defect and underlying molecular mechanisms that have been perturbed. In order to compare the consequence of infection caused by Gram positive and negative bacteria, Staphylococcus aureus and Vibrio alginolyticus were chosen as candidate pathogens, respectively. Microscopic observations revealed notable changes in tail morphology during 24 h of infection, as along with change in sperm size and activation. The Real Time-PCR results suggest the plausible down regulation of DBL-1/TGF-β pathway suggesting the morphological change in the tail. Shotgun proteomics further lead to the identification of MAG-1, Magonashi Protein a candidate regulatory player that affects spermatogenesis and HIF-1 that regulate during stress in both Gram positive and Gram negative infection. The protein-protein interaction with detected proteins revealed RACK-1 protein and mTOR pathway in S. aureus and V. alginolyticus respectively interacting with MAG-1 protein, which plays an important role in spermatogenesis termination in hermaphrodites during L4 to adult switch. This study paves a way to understand the candidate players that regulate reproduction during bacterial infection. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Inhaled Antibiotics for Gram-Negative Respiratory Infections

    Science.gov (United States)

    Fraidenburg, Dustin R.; Scardina, Tonya

    2016-01-01

    SUMMARY Gram-negative organisms comprise a large portion of the pathogens responsible for lower respiratory tract infections, especially those that are nosocomially acquired, and the rate of antibiotic resistance among these organisms continues to rise. Systemically administered antibiotics used to treat these infections often have poor penetration into the lung parenchyma and narrow therapeutic windows between efficacy and toxicity. The use of inhaled antibiotics allows for maximization of target site concentrations and optimization of pharmacokinetic/pharmacodynamic indices while minimizing systemic exposure and toxicity. This review is a comprehensive discussion of formulation and drug delivery aspects, in vitro and microbiological considerations, pharmacokinetics, and clinical outcomes with inhaled antibiotics as they apply to disease states other than cystic fibrosis. In reviewing the literature surrounding the use of inhaled antibiotics, we also highlight the complexities related to this route of administration and the shortcomings in the available evidence. The lack of novel anti-Gram-negative antibiotics in the developmental pipeline will encourage the innovative use of our existing agents, and the inhaled route is one that deserves to be further studied and adopted in the clinical arena. PMID:27226088

  4. A Gestalt approach to Gram-negative entry.

    Science.gov (United States)

    Silver, Lynn L

    2016-12-15

    A major obstacle confronting the discovery and development of new antibacterial agents to combat resistant Gram-negative (GN) organisms is the lack of a rational process for endowing compounds with properties that allow (or promote) entry into the bacterial cytoplasm. The major permeability difference between GN and Gram-positive (GP) bacteria is the GN outer membrane (OM) which is a permeability barrier itself and potentiates efflux pumps that expel compounds. Based on the fact that OM-permeable and efflux-deleted GNs are sensitive to many anti-GP drugs, recent efforts to approach the GN entry problem have focused on ways of avoiding efflux and transiting or compromising the OM, with the tacit assumption that this could allow entry of compounds into the GN cytoplasm. But bypassing the OM and efflux obstacles does not take into account the additional requirement of penetrating the cytoplasmic membrane (CM) whose sieving properties appear to be orthogonal to that of the OM. That is, tailoring compounds to transit the OM may well compromise their ability to enter the cytoplasm. Thus, a Gestalt approach to understanding the chemical requirements for GN entry seems a useful adjunct. This might consist of characterizing compounds which reach the cytoplasm, grouping (or binning) by routes of entry and formulating chemical 'rules' for those bins. This will require acquisition of data on large numbers of compounds, using non-activity-dependent methods of measuring accumulation in the cytoplasm. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Daptomycin: a novel lipopeptide antibiotic against Gram-positive pathogens

    Directory of Open Access Journals (Sweden)

    Andres Beiras-Fernandez

    2010-08-01

    Full Text Available Andres Beiras-Fernandez1,*, Ferdinand Vogt1,*, Ralf Sodian1, Florian Weis21Department of Cardiac Surgery, University Hospital Großhadern, Ludwig-Maximilian-University, Munich, Germany; 2Department of Anesthesiology, University Hospital Großhadern, Ludwig-Maximilian-University, Munich, Germany *Andres Beiras-Fernandez and Ferdinand Vogt contributed equally to this paperAbstract: The aim of this review is to summarize the historical background of drug resistance of Gram-positive pathogens as well as to describe in detail the novel lipopeptide antibiotic daptomycin. Pharmacological and pharmacokinetic aspects are reviewed and the current clinical use of daptomycin is presented. Daptomycin seems to be a reliable drug in the treatment of complicated skin and skin structure infections, infective right-sided endocarditis, and bacteremia caused by Gram-positive agents. Its unique mechanism of action and its low resistance profile, together with its rapid bactericidal action make it a favorable alternative to vancomycin in multi-drug resistant cocci. The role of daptomycin in the treatment of prosthetic material infections, osteomyelitis, and urogenital infections needs to be evaluated in randomized clinical trials.Keywords: daptomycin, multi-drug resistance, methicillin-resistant Staphylococcus aureus (MRSA, pneumonia, urinary tract infection, left-sided endocarditis

  6. GRAM Series of Atmospheric Models for Aeroentry and Aeroassist

    Science.gov (United States)

    Duvall, Aleta; Justus, C. G.; Keller, Vernon W.

    2005-01-01

    The eight destinations in the Solar System with sufficient atmosphere for either aeroentry or aeroassist, including aerocapture, are: Venus, Earth, Mars, Jupiter, Saturn; Uranus. and Neptune, and Saturn's moon Titan. Engineering-level atmospheric models for four of these (Earth, Mars, Titan, and Neptune) have been developed for use in NASA's systems analysis studies of aerocapture applications in potential future missions. Work has recently commenced on development of a similar atmospheric model for Venus. This series of MSFC-sponsored models is identified as the Global Reference Atmosphere Model (GRAM) series. An important capability of all of the models in the GRAM series is their ability to simulate quasi-random perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design. Example applications for Earth aeroentry and Mars aerocapture systems analysis studies are presented and illustrated. Current and planned updates to the Earth and Mars atmospheric models, in support of NASA's new exploration vision, are also presented.

  7. Charge effect on the photoinactivation of Gram-negative and Gram-positive bacteria by cationic meso-substituted porphyrins

    Directory of Open Access Journals (Sweden)

    Tomé Augusto C

    2009-04-01

    Full Text Available Abstract Background In recent times photodynamic antimicrobial therapy has been used to efficiently destroy Gram (+ and Gram (- bacteria using cationic porphyrins as photosensitizers. There is an increasing interest in this approach, namely in the search of photosensitizers with adequate structural features for an efficient photoinactivation process. In this study we propose to compare the efficiency of seven cationic porphyrins differing in meso-substituent groups, charge number and charge distribution, on the photodynamic inactivation of a Gram (+ bacterium (Enterococcus faecalis and of a Gram (- bacterium (Escherichia coli. The present study complements our previous work on the search for photosensitizers that might be considered good candidates for the photoinactivation of a large spectrum of environmental microorganisms. Results Bacterial suspension (107 CFU mL-1 treated with different photosensitizers concentrations (0.5, 1.0 and 5.0 μM were exposed to white light (40 W m-2 for a total light dose of 64.8 J cm-2. The most effective photosensitizers against both bacterial strains were the Tri-Py+-Me-PF and Tri-Py+-Me-CO2Me at 5.0 μM with a light fluence of 64.8 J cm-2, leading to > 7.0 log (> 99,999% of photoinactivation. The tetracationic porphyrin also proved to be a good photosensitizer against both bacterial strains. Both di-cationic and the monocationic porphyrins were the least effective ones. Conclusion The number of positive charges, the charge distribution in the porphyrins' structure and the meso-substituent groups seem to have different effects on the photoinactivation of both bacteria. As the Tri-Py+-Me-PF porphyrin provides the highest log reduction using lower light doses, this photosensitizer can efficiently photoinactivate a large spectrum of environmental bacteria. The complete inactivation of both bacterial strains with low light fluence (40 W m-2 means that the photodynamic approach can be applied to wastewater treatment

  8. Simultaneous Fluorescent Gram Staining and Activity Assessment of Activated Sludge Bacteria

    Science.gov (United States)

    Forster, Scott; Snape, Jason R.; Lappin-Scott, Hilary M.; Porter, Jonathan

    2002-01-01

    Wastewater treatment is one of the most important commercial biotechnological processes, and yet the component bacterial populations and their associated metabolic activities are poorly understood. The novel fluorescent dye hexidium iodide allows assessment of Gram status by differential absorption through bacterial cell walls. Differentiation between gram-positive and gram-negative wastewater bacteria was achieved after flow cytometric analysis. This study shows that the relative proportions of gram-positive and gram-negative bacterial cells identified by traditional microscopy and hexidium iodide staining were not significantly different. Dual staining of cells for Gram status and activity proved effective in analyzing mixtures of cultured bacteria and wastewater populations. Levels of highly active organisms at two wastewater treatment plants, both gram positive and gram negative, ranged from 1.5% in activated sludge flocs to 16% in the activated sludge fluid. Gram-positive organisms comprised Gram status and activity within activated sludge samples over a 4-day period showed significant differences over time. This method provides a rapid, quantitative measure of Gram status linked with in situ activity within wastewater systems. PMID:12324319

  9. LPS-binding protein-deficient mice have an impaired defense against Gram-negative but not Gram-positive pneumonia

    NARCIS (Netherlands)

    Branger, Judith; Florquin, Sandrine; Knapp, Sylvia; Leemans, Jaklien C.; Pater, Jennie M.; Speelman, Peter; Golenbock, Douglas T.; van der Poll, Tom

    2004-01-01

    LPS-binding protein (LBP) can facilitate the transfer of cell wall components of both Gram-negative bacteria (LPS) and Gram-positive bacteria (lipoteichoic acid) to inflammatory cells. Although LBP is predominantly produced in the liver, recent studies have indicated that this protein is also

  10. A pathway closely related to the (D)-tagatose pathway of gram-negative enterobacteria identified in the gram-positive bacterium Bacillus licheniformis.

    Science.gov (United States)

    Van der Heiden, Edwige; Delmarcelle, Michaël; Lebrun, Sarah; Freichels, Régine; Brans, Alain; Vastenavond, Christian M; Galleni, Moreno; Joris, Bernard

    2013-06-01

    We report the first identification of a gene cluster involved in d-tagatose catabolism in Bacillus licheniformis. The pathway is closely related to the d-tagatose pathway of the Gram-negative bacterium Klebsiella oxytoca, in contrast to the d-tagatose 6-phosphate pathway described in the Gram-positive bacterium Staphylococcus aureus.

  11. A Pathway Closely Related to the d-Tagatose Pathway of Gram-Negative Enterobacteria Identified in the Gram-Positive Bacterium Bacillus licheniformis

    Science.gov (United States)

    Van der Heiden, Edwige; Lebrun, Sarah; Freichels, Régine; Brans, Alain; Vastenavond, Christian M.; Galleni, Moreno; Joris, Bernard

    2013-01-01

    We report the first identification of a gene cluster involved in d-tagatose catabolism in Bacillus licheniformis. The pathway is closely related to the d-tagatose pathway of the Gram-negative bacterium Klebsiella oxytoca, in contrast to the d-tagatose 6-phosphate pathway described in the Gram-positive bacterium Staphylococcus aureus. PMID:23524682

  12. A Pathway Closely Related to the d-Tagatose Pathway of Gram-Negative Enterobacteria Identified in the Gram-Positive Bacterium Bacillus licheniformis

    OpenAIRE

    Van der Heiden, Edwige; Delmarcelle, Michaël; Lebrun, Sarah; Freichels, Régine; Brans, Alain; Vastenavond, Christian M.; Galleni, Moreno; Joris, Bernard

    2013-01-01

    We report the first identification of a gene cluster involved in d-tagatose catabolism in Bacillus licheniformis. The pathway is closely related to the d-tagatose pathway of the Gram-negative bacterium Klebsiella oxytoca, in contrast to the d-tagatose 6-phosphate pathway described in the Gram-positive bacterium Staphylococcus aureus.

  13. Comparative activity of tigecycline and tetracycline on Gram-negative and Gram-positive bacteria revealed by a multicentre study in four North European countries

    DEFF Research Database (Denmark)

    Nilsson, Lennart E; Frimodt-Møller, Niels; Vaara, Martti

    2011-01-01

    This study involves a multicentre surveillance of tigecycline and tetracycline activity against Gram-negative and Gram-positive bacteria from primary care centres (PCCs), general hospital wards (GHWs) and intensive care units (ICUs) in Denmark (n = 9), Finland (n = 10), Norway (n = 7) and Sweden (n...

  14. Cerium oxide and iron oxide nanoparticles abolish the antibacterial activity of ciprofloxacin against gram positive and gram negative biofilm bacteria.

    Science.gov (United States)

    Masadeh, Majed M; Karasneh, Ghadah A; Al-Akhras, Mohammad A; Albiss, Borhan A; Aljarah, Khaled M; Al-Azzam, Sayer I; Alzoubi, Karem H

    2015-05-01

    Metal oxide nanoparticles have been suggested as good candidates for the development of antibacterial agents. Cerium oxide (CeO2) and iron oxide (Fe2O3) nanoparticles have been utilized in a number of biomedical applications. Here, the antibacterial activity of CeO2 and Fe2O3 nanoparticles were evaluated on a panel of gram positive and gram negative bacteria in both the planktonic and biofilm cultures. Additionally, the effect of combining CeO2 and Fe2O3 nanoparticles with the broad spectrum antibiotic ciprofloxacin on tested bacteria was investigated. Thus, minimum inhibitory concentrations (MICs) of CeO2 and Fe2O3 nanoparticles that are required to inhibit bacterial planktonic growth and bacterial biofilm, were evaluated, and were compared to the MICs of the broad spectrum antibiotic ciprofloxacin alone or in the presence of CeO2 and Fe2O3 nanoparticles. Results of this study show that both CeO2 and Fe2O3 nanoparticles fail to inhibit bacterial growth and biofilm biomass for all the bacterial strains tested. Moreover, adding CeO2 or Fe2O3 nanoparticles to the broad spectrum antibiotic ciprofloxacin almost abolished its antibacterial activity. Results of this study suggest that CeO2 and Fe2O3 nanoparticles are not good candidates as antibacterial agents, and they could interfere with the activity of important antibiotics.

  15. Comparison of gram-negative and gram-positive hematogenous pyogenic spondylodiscitis: clinical characteristics and outcomes of treatment.

    Science.gov (United States)

    Lee, Ching-Yu; Wu, Meng-Huang; Cheng, Chin-Chang; Huang, Tsung-Jen; Huang, Tsung-Yu; Lee, Chien-Yin; Huang, Jou-Chen; Li, Yen-Yao

    2016-12-06

    To the best of our knowledge, no study has compared gram-negative bacillary hematogenous pyogenic spondylodiscitis (GNB-HPS) with gram-positive coccal hematogenous pyogenic spondylodiscitis (GPC-HPS) regarding their clinical characteristics and outcomes. From January 2003 to January 2013, 54 patients who underwent combined antibiotic and surgical therapy in the treatment of hematogenous pyogenic spondylodiscitis were included. Compared with 37 GPC-HPS patients, the 17 GNB-HPS patients were more often found to be older individuals, a history of cancer, and a previous history of symptomatic urinary tract infection. They also had a less incidence of epidural abscess formation compared with GPC-HPS patients from findings on magnetic resonance imaging (MRI). Constitutional symptoms were the primary reasons for initial physician visits in GNB-HPS patients whereas pain in the affected spinal region was the most common manifestation in GPC-HPS patients at initial visit. The clinical outcomes of GNB-HPS patients under combined surgical and antibiotic treatment were not different from those of GPC-HPS patients. In multivariate analysis, independent predicting risk factors for GNB-HPS included a malignant history and constitutional symptoms and that for GPC-HPS was epidural abscess. The clinical manifestations and MRI presentations of GNB-HPS were distinguishable from those of GPC-HPS.

  16. Biocompatible Fe3O4 Increases the Efficacy of Amoxicillin Delivery against Gram-Positive and Gram-Negative Bacteria

    Directory of Open Access Journals (Sweden)

    Alexandru Mihai Grumezescu

    2014-04-01

    Full Text Available This paper reports the synthesis and characterization of amoxicillin- functionalized magnetite nanostructures (Fe3O4@AMO, revealing and discussing several biomedical applications of these nanomaterials. Our results proved that 10 nm Fe3O4@AMO nanoparticles does not alter the normal cell cycle progression of cultured diploid cells, and an in vivo murine model confirms that the nanostructures disperse through the host body and tend to localize in particular sites and organs. The nanoparticles were found clustered especially in the lungs, kidneys and spleen, next to the blood vessels at this level, while being totally absent in the brain and liver, suggesting that they are circulated through the blood flow and have low toxicity. Fe3O4@AMO has the ability to be easily circulated through the body and optimizations may be done so these nanostructures cluster to a specific target region. Functionalized magnetite nanostructures proved a great antimicrobial effect, being active against both the Gram positive pathogen S. aureus and the Gram negative pathogen E. coli. The fabricated nanostructures significantly reduced the minimum inhibitory concentration (MIC of the active drug. This result has a great practical relevance, since the functionalized nanostructures may be used for decreasing the therapeutic doses which usually manifest great severe side effects, when administrated in high doses. Fe3O4@AMO represents also a suitable approach for the development of new alternative strategies for improving the activity of therapeutic agents by targeted delivery and controlled release.

  17. Preparation and evaluation of antibacterial potential of Pithecellobium dulce root extract against Gram positive and Gram negative bacteria.

    Science.gov (United States)

    Bhat, Muneer Ahmad; Malik, Rayees Ahmad; Prakash, Poonam; Lone, Ali Mohd

    2018-03-01

    In the present study hexane, benzene, ethyl acetate and ethanol extracts of Pithecellobium dulce root were prepared using soxhlet extractor. The extracts were evaluated for antibacterial activity against one Gram positive (Staphylococcus aureus) and three Gram negative (Acetobacter aceti, Acetobacter aceti, Klebsiella pneumoniae) strains. Disc diffusion method revealed promising antibacterial activity of the extracts prepared in polar solvents (ethyl acetate and ethanol) compared to non-polar solvents (hexane and benzene). Ethanolic root extract was found to be most active against Acetobacter aceti, Staphylococcus aureus, Klebsiella pneumonia and Enterobacter aerogenes bacterial strains. The zone of inhibition of ethanolic root extract against Acetobacter aceti, Staphylococcus aureus, Klebsiella pneumonia and Enterobacter aerogenes bacterial strains was 15.4, 11.0, 19.0 and 13.0 mm, respectively at 100 mg concentration. Ethyl acetate extract also exhibited good antibacterial activity against Entrobacter aerogenes, Klebsiella pneumonia and Acetobacter aceti. The zone of inhibition of ethyl acetate root extracts against Entrobacter aerogenes, Acetobacter aceti and Klebsiella pneumonia was 10.5, 18.0 and 10.0 mm, respectively. The benzene extract showed some activity against Acetobacter aceti with the zone of inhibition 10.0 mm. The antibacterial activity of Pithecellobium dulce root hexane extract was found to be negligible against all the four tested strains of bacteria. These findings suggest that ethanolic and ethyl acetate root extracts of Pithecellobium dulce has potential as effective anti-bacterial agent. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Dose-Dependent Antimicrobial Activity of Silver Nanoparticles on Polycaprolactone Fibers against Gram-Positive and Gram-Negative Bacteria

    Directory of Open Access Journals (Sweden)

    Erick Pazos-Ortiz

    2017-01-01

    Full Text Available The adhesion ability and adaptability of bacteria, coupled with constant use of the same bactericides, have made the increase in the diversity of treatments against infections necessary. Nanotechnology has played an important role in the search for new ways to prevent and treat infections, including the use of metallic nanoparticles with antibacterial properties. In this study, we worked on the design of a composite of silver nanoparticles (AgNPS embedded in poly-epsilon-caprolactone nanofibers and evaluated its antimicrobial properties against various Gram-positive and Gram-negative microorganisms associated with drug-resistant infections. Polycaprolactone-silver composites (PCL-AgNPs were prepared in two steps. The first step consisted in the reduction in situ of Ag+ ions using N,N-dimethylformamide (DMF in tetrahydrofuran (THF solution, and the second step involved the simple addition of polycaprolactone before electrospinning process. Antibacterial activity of PCL-AgNPs nanofibers against E. coli, S. mutans, K. pneumoniae, S. aureus, P. aeruginosa, and B. subtilis was evaluated. Results showed sensibility of E. coli, K. pneumoniae, S. aureus, and P. aeruginosa, but not for B. subtilis and S. mutans. This antimicrobial activity of PCL-AgNPs showed significant positive correlations associated with the dose-dependent effect. The antibacterial property of the PCL/Ag nanofibers might have high potential medical applications in drug-resistant infections.

  19. Biocompatible Fe3O4 increases the efficacy of amoxicillin delivery against Gram-positive and Gram-negative bacteria.

    Science.gov (United States)

    Grumezescu, Alexandru Mihai; Gestal, Monica Cartelle; Holban, Alina Maria; Grumezescu, Valentina; Vasile, Bogdan Stefan; Mogoantă, Laurențiu; Iordache, Florin; Bleotu, Coralia; Mogoșanu, George Dan

    2014-04-22

    This paper reports the synthesis and characterization of amoxicillin- functionalized magnetite nanostructures (Fe3O4@AMO), revealing and discussing several biomedical applications of these nanomaterials. Our results proved that 10 nm Fe3O4@AMO nanoparticles does not alter the normal cell cycle progression of cultured diploid cells, and an in vivo murine model confirms that the nanostructures disperse through the host body and tend to localize in particular sites and organs. The nanoparticles were found clustered especially in the lungs, kidneys and spleen, next to the blood vessels at this level, while being totally absent in the brain and liver, suggesting that they are circulated through the blood flow and have low toxicity. Fe3O4@AMO has the ability to be easily circulated through the body and optimizations may be done so these nanostructures cluster to a specific target region. Functionalized magnetite nanostructures proved a great antimicrobial effect, being active against both the Gram positive pathogen S. aureus and the Gram negative pathogen E. coli. The fabricated nanostructures significantly reduced the minimum inhibitory concentration (MIC) of the active drug. This result has a great practical relevance, since the functionalized nanostructures may be used for decreasing the therapeutic doses which usually manifest great severe side effects, when administrated in high doses. Fe3O4@AMO represents also a suitable approach for the development of new alternative strategies for improving the activity of therapeutic agents by targeted delivery and controlled release.

  20. Inhibition of various gram-positive and gram-negative bacteria growth on selenium nanoparticle coated paper towels.

    Science.gov (United States)

    Wang, Qi; Larese-Casanova, Philip; Webster, Thomas J

    2015-01-01

    There are wide spread bacterial contamination issues on various paper products, such as paper towels hanging in sink splash zones or those used to clean surfaces, filter papers used in water and air purifying systems, and wrappings used in the food industry; such contamination may lead to the potential spread of bacteria and consequent severe health concerns. In this study, selenium nanoparticles were coated on normal paper towel surfaces through a quick precipitation method, introducing antibacterial properties to the paper towels in a healthy way. Their effectiveness at preventing biofilm formation was tested in bacterial assays involving Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus epidermidis. The results showed significant and continuous bacteria inhibition with about a 90% reduction from 24 to 72 hours for gram-positive bacteria including S. aureus and S. epidermidis. The selenium coated paper towels also showed significant inhibition of gram-negative bacteria like P. aeruginosa and E. coli growth at about 57% and 84%, respectively, after 72 hours of treatment. Therefore, this study established a promising selenium-based antibacterial strategy to prevent bacterial growth on paper products, which may lead to the avoidance of bacteria spreading and consequent severe health concerns.

  1. Antibacterial activity of sphingoid bases and fatty acids against Gram-positive and Gram-negative bacteria.

    Science.gov (United States)

    Fischer, Carol L; Drake, David R; Dawson, Deborah V; Blanchette, Derek R; Brogden, Kim A; Wertz, Philip W

    2012-03-01

    There is growing evidence that the role of lipids in innate immunity is more important than previously realized. How lipids interact with bacteria to achieve a level of protection, however, is still poorly understood. To begin to address the mechanisms of antibacterial activity, we determined MICs and minimum bactericidal concentrations (MBCs) of lipids common to the skin and oral cavity--the sphingoid bases D-sphingosine, phytosphingosine, and dihydrosphingosine and the fatty acids sapienic acid and lauric acid--against four Gram-negative bacteria and seven Gram-positive bacteria. Exact Kruskal-Wallis tests of these values showed differences among lipid treatments (P 500 μg/ml). Sapienic acid (MBC range, 31.3 to 375.0 μg/ml) was active against Streptococcus sanguinis, Streptococcus mitis, and Fusobacterium nucleatum but not active against Escherichia coli, Staphylococcus aureus, S. marcescens, P. aeruginosa, Corynebacterium bovis, Corynebacterium striatum, and Corynebacterium jeikeium (MBC > 500 μg/ml). Lauric acid (MBC range, 6.8 to 375.0 μg/ml) was active against all bacteria except E. coli, S. marcescens, and P. aeruginosa (MBC > 500 μg/ml). Complete killing was achieved as early as 0.5 h for some lipids but took as long as 24 h for others. Hence, sphingoid bases and fatty acids have different antibacterial activities and may have potential for prophylactic or therapeutic intervention in infection.

  2. Nanoparticle targeting of Gram-positive and Gram-negative bacteria for magnetic-based separations of bacterial pathogens

    Science.gov (United States)

    Lu, Hoang D.; Yang, Shirley S.; Wilson, Brian K.; McManus, Simon A.; Chen, Christopher V. H.-H.; Prud'homme, Robert K.

    2017-04-01

    Antimicrobial resistance is a healthcare problem of increasing significance, and there is increasing interest in developing new tools to address bacterial infections. Bacteria-targeting nanoparticles hold promise to improve drug efficacy, compliance, and safety. In addition, nanoparticles can also be used for novel applications, such as bacterial imaging or bioseperations. We here present the use of a scalable block-copolymer-directed self-assembly process, Flash NanoPrecipitation, to form zinc(II)-bis(dipicolylamine) modified nanoparticles that bind to both Gram-positive and Gram-negative bacteria with specificity. Particles have tunable surface ligand densities that change particle avidity and binding efficacy. A variety of materials can be encapsulated into the core of the particles, such as optical dyes or iron oxide colloids, to produce imageable and magnetically active bacterial targeting constructs. As a proof-of-concept, these particles are used to bind and separate bacteria from solution in a magnetic column. Magnetic manipulation and separation would translate to a platform for pathogen identification or removal. These magnetic and targeted nanoparticles enable new methods to address bacterial infections.

  3. Inhaled antibiotics for gram-negative respiratory infections.

    Science.gov (United States)

    Hudson, Ryan; Olson Blair, Brooke

    2011-10-01

    Several disease states create conditions that lead to opportunistic Gram-negative respiratory infections. Inhalation is the most direct and, until recently, underutilized means of antimicrobial drug targeting for respiratory tract infections. All approved antimicrobial agents for administration by inhalation are indicated for Pseudomonas aeruginosa infections in patients with cystic fibrosis. These inhaled therapies have directly contributed to a significant reduction in exacerbations and hospitalizations in this patient population over the last few decades. The relentless adaptation of pathogenic organisms to current treatment options demands that the pharmaceutical industry continue designing next-generation antimicrobial agents over 70 years after they were first introduced. Recent technological advances in inhalation devices and drug formulation techniques have broadened the scope of antimicrobial structural classes that can be investigated by inhalation; however, there is an urgent need to discover novel compounds with improved resistance profiles relative to those drugs that are already marketed.

  4. The gram-negative bacterial periplasm: Size matters.

    Directory of Open Access Journals (Sweden)

    Samuel I Miller

    2018-01-01

    Full Text Available Gram-negative bacteria are surrounded by two membrane bilayers separated by a space termed the periplasm. The periplasm is a multipurpose compartment separate from the cytoplasm whose distinct reducing environment allows more efficient and diverse mechanisms of protein oxidation, folding, and quality control. The periplasm also contains structural elements and important environmental sensing modules, and it allows complex nanomachines to span the cell envelope. Recent work indicates that the size or intermembrane distance of the periplasm is controlled by periplasmic lipoproteins that anchor the outer membrane to the periplasmic peptidoglycan polymer. This periplasm intermembrane distance is critical for sensing outer membrane damage and dictates length of the flagellar periplasmic rotor, which controls motility. These exciting results resolve longstanding debates about whether the periplasmic distance has a biological function and raise the possibility that the mechanisms for maintenance of periplasmic size could be exploited for antibiotic development.

  5. Marine Compounds with Therapeutic Potential in Gram-Negative Sepsis

    Directory of Open Access Journals (Sweden)

    Irina Yermak

    2013-06-01

    Full Text Available This paper concerns the potential use of compounds, including lipid A, chitosan, and carrageenan, from marine sources as agents for treating endotoxemic complications from Gram-negative infections, such as sepsis and endotoxic shock. Lipid A, which can be isolated from various species of marine bacteria, is a potential antagonist of bacterial endotoxins (lipopolysaccharide (LPSs. Chitosan is a widespread marine polysaccharide that is derived from chitin, the major component of crustacean shells. The potential of chitosan as an LPS-binding and endotoxin-neutralizing agent is also examined in this paper, including a discussion on the generation of hydrophobic chitosan derivatives to increase the binding affinity of chitosan to LPS. In addition, the ability of carrageenan, which is the polysaccharide of red alga, to decrease the toxicity of LPS is discussed. We also review data obtained using animal models that demonstrate the potency of carrageenan and chitosan as antiendotoxin agents.

  6. Enhanced antibacterial and anti-biofilm activities of silver nanoparticles against Gram-negative and Gram-positive bacteria

    Science.gov (United States)

    Gurunathan, Sangiliyandi; Han, Jae Woong; Kwon, Deug-Nam; Kim, Jin-Hoi

    2014-07-01

    Silver nanoparticles (AgNPs) have been used as antibacterial, antifungal, antiviral, anti-inflammtory, and antiangiogenic due to its unique properties such as physical, chemical, and biological properties. The present study was aimed to investigate antibacterial and anti-biofilm activities of silver nanoparticles alone and in combination with conventional antibiotics against various human pathogenic bacteria. Here, we show that a simple, reliable, cost effective and green method for the synthesis of AgNPs by treating silver ions with leaf extract of Allophylus cobbe. The A. cobbe-mediated synthesis of AgNPs (AgNPs) was characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Furthermore, the antibacterial and anti-biofilm activity of antibiotics or AgNPs, or combinations of AgNPs with an antibiotic was evaluated using a series of assays: such as in vitro killing assay, disc diffusion assay, biofilm inhibition, and reactive oxygen species generation in Pseudomonas aeruginosa, Shigella flexneri, Staphylococcus aureus, and Streptococcus pneumonia. The results suggest that, in combination with antibiotics, there were significant antimicrobial and anti-biofilm effects at lowest concentration of AgNPs using a novel plant extract of A. cobbe, otherwise sublethal concentrations of the antibiotics. The significant enhancing effects were observed for ampicillin and vancomycin against Gram-negative and Gram-positive bacteria, respectively. These data suggest that combining antibiotics and biogenic AgNPs can be used therapeutically for the treatment of infectious diseases caused by bacteria. This study presented evidence of antibacterial and anti-biofilm effects of A. cobbe-mediated synthesis of AgNPs and their enhanced capacity against various human pathogenic bacteria. These results

  7. Flow cytometric evaluation of physico-chemical impact on Gram-positive and Gram-negative bacteria

    Directory of Open Access Journals (Sweden)

    Antje eFröhling

    2015-09-01

    Full Text Available Since heat sensitivity of fruits and vegetables limits the application of thermal inactivation processes, new emerging inactivation technologies have to be established to fulfil the requirements of food safety without affecting the produce quality. The efficiency of inactivation treatments has to be ensured and monitored. Monitoring of inactivation effects is commonly performed using traditional cultivation methods which have the disadvantage of the time span needed to obtain results.The aim of this study was to compare the inactivation effects of peracetic acid (PAA, ozonated water (O3 and cold atmospheric pressure plasma (CAPP on Gram-positive and Gram-negative bacteria using flow cytometric methods. E. coli cells were completely depolarized after treatment (15 s with 0.25 % PAA at 10 °C, and after treatment (10 s with 3.8 mg l-1 O3 at 12°C. The membrane potential of CAPP treated cells remained almost constant at an operating power of 20 W over a time period of 3 min, and subsequently decreased within 30 s of further treatment. Complete membrane permeabilization was observed after 10 s O3 treatment, but treatment with PAA and CAPP did not completely permeabilize the cells within 2 min and 4 min, respectively. Similar results were obtained for esterase activity. O3 inactivates cellular esterase but esterase activity was detected after 4 min CAPP treatment and 2 min PAA treatment. L. innocua cells and P. carotovorum cells were also permeabilized instantaneously by O3 treatment at concentrations of 3.8 ± 1 mg l-1. However, higher membrane permeabilization of L. innocua and P. carotovorum than of E. coli was observed at CAPP treatment of 20 W. The degree of bacterial damage due to the inactivation processes is highly dependent on treatment parameters as well as on treated bacteria. Important information regarding the inactivation mechanisms can be obtained by flow cytometric measurements and this enables the definition of critical process

  8. An unusual class of anthracyclines potentiate Gram-positive antibiotics in intrinsically resistant Gram-negative bacteria

    Science.gov (United States)

    Cox, Georgina; Koteva, Kalinka; Wright, Gerard D.

    2014-01-01

    Objectives An orthogonal approach taken towards novel antibacterial drug discovery involves the identification of small molecules that potentiate or enhance the activity of existing antibacterial agents. This study aimed to identify natural-product rifampicin adjuvants in the intrinsically resistant organism Escherichia coli. Methods E. coli BW25113 was screened against 1120 actinomycete fermentation extracts in the presence of subinhibitory (2 mg/L) concentrations of rifampicin. The active molecule exhibiting the greatest rifampicin potentiation was isolated using activity-guided methods and identified using mass and NMR spectroscopy. Susceptibility testing and biochemical assays were used to determine the mechanism of antibiotic potentiation. Results The anthracycline Antibiotic 301A1 was isolated from the fermentation broth of a strain of Streptomyces (WAC450); the molecule was shown to be highly synergistic with rifampicin (fractional inhibitory concentration index = 0.156) and moderately synergistic with linezolid (FIC index = 0.25) in both E. coli and Acinetobacter baumannii. Activity was associated with inhibition of efflux and the synergistic phenotype was lost when tested against E. coli harbouring mutations within the rpoB gene. Structure–activity relationship studies revealed that other anthracyclines do not synergize with rifampicin and removal of the sugar moiety of Antibiotic 301A1 abolishes activity. Conclusions Screening only a subsection of our natural product library identified a small-molecule antibiotic adjuvant capable of sensitizing Gram-negative bacteria to antibiotics to which they are ordinarily intrinsically resistant. This result demonstrates the great potential of this approach in expanding antibiotic effectiveness in the face of the growing challenge of resistance in Gram-negatives. PMID:24627312

  9. Antibacterial activity and interactions of plant essential oil combinations against Gram-positive and Gram-negative bacteria

    Directory of Open Access Journals (Sweden)

    Cristina Anamaria Semeniuc

    2017-04-01

    Full Text Available The aim of this study was to compare the antibacterial effects of several essential oils (EOs alone and in combination against different Gram-positive and Gram-negative bacteria associated with food products. Parsley, lovage, basil, and thyme EOs, as well as their mixtures (1:1, v/v, were tested against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Salmonella typhimurium. The inhibitory effects ranged from strong (thyme EO against E. coli to no inhibition (parsley EO against P. aeruginosa. Thyme EO exhibited strong (against E. coli, moderate (against S. typhimurium and B. cereus, or mild inhibitory effects (against P. aeruginosa and S. aureus, and basil EO showed mild (against E. coli and B. cereus or no inhibitory effects (against S. typhimurium, P. aeruginosa, and S. aureus. Parsley and lovage EOs revealed no inhibitory effects against all tested strains. Combinations of lovage/thyme and basil/thyme EOs displayed antagonistic effects against all bacteria, parsley/thyme EOs against B. cereus, S. aureus, P. aeruginosa, and E. coli, and lovage/basil EOs against B. cereus and E. coli. Combinations of parsley/lovage and parsley/basil EOs exhibited indifferent effects against all bacteria. The combination of lovage/basil EO showed indifferent effect against S. aureus, P. aeruginosa, and S. typhimurium, and the combination parsley/thyme EO against S. typhimurium. Thyme EO has the highest percentage yield and antibacterial potential from all tested formulations; its combination with parsley, lovage, and basil EOs determines a reduction of its antibacterial activity. Hence, it is recommended to be used alone as the antibacterial agent.

  10. Antibacterial activity and interactions of plant essential oil combinations against Gram-positive and Gram-negative bacteria.

    Science.gov (United States)

    Semeniuc, Cristina Anamaria; Pop, Carmen Rodica; Rotar, Ancuţa Mihaela

    2017-04-01

    The aim of this study was to compare the antibacterial effects of several essential oils (EOs) alone and in combination against different Gram-positive and Gram-negative bacteria associated with food products. Parsley, lovage, basil, and thyme EOs, as well as their mixtures (1:1, v/v), were tested against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Salmonella typhimurium. The inhibitory effects ranged from strong (thyme EO against E. coli) to no inhibition (parsley EO against P. aeruginosa). Thyme EO exhibited strong (against E. coli), moderate (against S. typhimurium and B. cereus), or mild inhibitory effects (against P. aeruginosa and S. aureus), and basil EO showed mild (against E. coli and B. cereus) or no inhibitory effects (against S. typhimurium, P. aeruginosa, and S. aureus). Parsley and lovage EOs revealed no inhibitory effects against all tested strains. Combinations of lovage/thyme and basil/thyme EOs displayed antagonistic effects against all bacteria, parsley/thyme EOs against B. cereus, S. aureus, P. aeruginosa, and E. coli, and lovage/basil EOs against B. cereus and E. coli. Combinations of parsley/lovage and parsley/basil EOs exhibited indifferent effects against all bacteria. The combination of lovage/basil EO showed indifferent effect against S. aureus, P. aeruginosa, and S. typhimurium, and the combination parsley/thyme EO against S. typhimurium. Thyme EO has the highest percentage yield and antibacterial potential from all tested formulations; its combination with parsley, lovage, and basil EOs determines a reduction of its antibacterial activity. Hence, it is recommended to be used alone as the antibacterial agent. Copyright © 2016. Published by Elsevier B.V.

  11. Utility of Gram Staining for Evaluation of the Quality of Cystic Fibrosis Sputum Samples

    Science.gov (United States)

    Nair, Bindu; Stapp, Jenny; Stapp, Lynn; Bugni, Linda; Van Dalfsen, Jill; Burns, Jane L.

    2002-01-01

    The microscopic examination of Gram-stained sputum specimens is very helpful in the evaluation of patients with community-acquired pneumonia and has also been recommended for use in cystic fibrosis (CF) patients. This study was undertaken to evaluate that recommendation. One hundred one sputum samples from CF patients were cultured for gram-negative bacilli and examined by Gram staining for both sputum adequacy (using the quality [Q] score) and bacterial morphology. Subjective evaluation of adequacy was also performed and categorized. Based on Q score evaluation, 41% of the samples would have been rejected despite a subjective appearance of purulence. Only three of these rejected samples were culture negative for gram-negative CF pathogens. Correlation between culture results and quantitative Gram stain examination was also poor. These data suggest that subjective evaluation combined with comprehensive bacteriology is superior to Gram staining in identifying pathogens in CF sputum. PMID:12149331

  12. Application of DNA comet assay for detection of radiation treatment of grams and pulses.

    Science.gov (United States)

    Khan, Hasan M; Khan, Ashfaq A; Khan, Sanaullah

    2011-12-01

    Several types of whole pulses (green lentils, red lentils, yellow lentils, chickpeas, green peas, cowpeas and yellow peas) and grams (black grams, red grams and white grams) have been investigated for the identification of radiation treatment using microgel electrophoresis of single cells (DNA comet assay). Pulses and grams were exposed to the radiation doses of 0.5, 1.0 and 5 kGy covering the legalized commercial dose range for protection from insect/pest infestations. All irradiated samples showed comet like stretching of fragmented DNA toward anode, which is expected for irradiated samples. Unirradiated samples showed many intact cells/nuclei in form of round stains or with short faint tails, which is typical for unirradiated food samples. The study shows that DNA comet assay can be used as a rapid, inexpensive and highly effective screening test for the detection of radiation treatment of foods, like pulses and grams.

  13. Widespread Abundance of Functional Bacterial Amyloid in Mycolata and Other Gram-Positive Bacteria

    DEFF Research Database (Denmark)

    Jordal, Peter Bruun; Dueholm, Morten Simonsen; Larsen, Poul

    2009-01-01

    Until recently, extracellular functional bacterial amyloid (FuBA) has been detected and characterized in only a few bacterial species, including Escherichia coli, Salmonella and Gram-positive Streptomyces coelicolor. Here we have probed Gram-positive bacteria with conformationally specific...... analysis. We conclude that amyloid is widespread among Gram-positive bacteria and may in many species constitute a hitherto overlooked integral part of the spores and the cellular envelope....

  14. Recognition of Pneumocystis carinii by gram stain in impression smears of lung tissue.

    Science.gov (United States)

    Felegie, T P; Pasculle, A W; Dekker, A

    1984-01-01

    In 12 of 20 (60%) biopsy-proven cases of Pneumocystis carinii pneumonia, the diagnosis was first suggested by examination of routine Gram stains of impression smears made from infected lung tissue and later confirmed by methenamine-silver staining. The cysts appeared as 5- to 7-microns unstained spheres, each containing six to eight intracystic gram-negative bodies (sporozoites). Although the Gram stain does not appear to be as sensitive as more traditional staining techniques for the detection of P. carinii, clinical microbiologists should be aware of the morphology of this organism in gram-stained specimens because this relatively simple procedure gives quick results. Images PMID:6084017

  15. Analysis of the Mechanism of Gram Differentiation by Use of a Filter-Paper Chromatographic Technique.

    Science.gov (United States)

    Bartholomew, J W; Cromwell, T; Gan, R

    1965-09-01

    Bartholomew, J. W. (University of Southern California, Los Angeles), Thomas Cromwell, and Richard Gan. Analysis of the mechanism of Gram differentiation by use of a filter-paper chromatographic technique. J. Bacteriol. 90:766-777. 1965.-Data are presented which demonstrate that the mechanism of gram-positivity could not be due solely to factors such as a single, specific gram-positive substrate, specific affinities of crystal violet for certain cellular components, a specific crystal violet-iodine-substrate complex, or to any specific characteristic of the dye, iodine, or solvent molecules. Ruptured cells of gram-positive organisms stain gram-negatively when subjected to a standard Gram-stain procedure. However, when stained fragments of broken cells were deposited in thick layers on the surface of filter-paper strips and exposed to decolorizers, the rate of dye release correlated with the Gram characteristic of the intact cell. Therefore, the intact cell in itself is not an absolute requirement for Gram differentiation. The data are interpreted as indicating that the mechanism of Gram differentiation primarily involves the rate of permeation of molecules (dye, iodine, solvent) through the interstitial spaces of cell-wall material.

  16. Ensaios sôbre lepra experimental: inoculações de três amostras de bacilos ácido-álcool resistentes (amostras "Chaves II", "Emilia" e "Hecke" isoladas de leprosos, em trinta doentes da Colônia Mirueira

    Directory of Open Access Journals (Sweden)

    H. C. de Souza-Araujo

    1951-03-01

    Full Text Available Com o fim de produzir o fenômeno de KOCH, os A. A. inocularam em 30 leprosos da Colônia Mirueira (Recife, de várias idades e formas clínicas, emulsões vivas de três culturas de bacilos ácido-álcool resistentes isolados de leprosos pro um dêles (S.A.. As doses inoculadas foram de 0,2 cc., por via intradérmica, em cada doente, das amostras "CII", "E" e "H" e mais da Leprolina S.A. (antígeno morto. No 10º dia da inoculação verificou-se que 24 dos 30 pacientes tiveram reação geral intensa; 2, reação moderada e 4, nenhuma reação geral. 16 dos 30 tiveram reação leprótica, sendo 10 em casos ativos (lepromatosos e 6 em inativos, e 17 dos 30 tiveram adenopatias inguinais. O inóculo "CII" produziu escaras de 1 x 1 e 2 x 2 cm. de diâmetro, com destruição total da pele, nos 30 pacientes (o total dêles; o inóculo "E" produziu escaras de igual intensidade em 29, o inóculo "H", escaras muitos mais benignas em 23, e a Leprolina em 10, naturalmente por ação concomitante de um dos outros três inóculos. No 10º dia foram semeadas em meio de LOEWENSTEIN secreções das escaras de sete dos 30 doentes, num total de 20 tubos, dos quais 19 produziram retroculuras, a amioria contaminada por fungos ou por bactérias cianófilas. De um doente foi obtido retrocultura cromogênica da escara produzida na intradérmoreação pela "Leprolina S. A.", macro e microscòpricamente indiferencável das amostras "CII" e "E". Aliás, pela extensiva experimentação feita com estas duas amostras, estamos nos inclinando por considerá-las como idênticas. No 18º dia da inoculação foram feitos 30 esfregaços de secreções de lesões experimentais de 13 doentes, com 15 resultados positivos (50%, apesar do exame tardio. As morfologias macro e microscópica das retroculturas obtidas em Recife confirmam os caracteres descritos nas culturas originais. Dêste rápido ensaio se conclui que a maioria dos pacientes apresentou o fenômeno de KOCH parcial ou

  17. Streptococcus mutans: a new Gram-positive paradigm?

    Science.gov (United States)

    Quivey, Robert G.; Koo, Hyun; Abranches, Jacqueline

    2013-01-01

    Despite the enormous contributions of the bacterial paradigms Escherichia coli and Bacillus subtilis to basic and applied research, it is well known that no single organism can be a perfect representative of all other species. However, given that some bacteria are difficult, or virtually impossible, to cultivate in the laboratory, that some are recalcitrant to genetic and molecular manipulation, and that others can be extremely dangerous to manipulate, the use of model organisms will continue to play an important role in the development of basic research. In particular, model organisms are very useful for providing a better understanding of the biology of closely related species. Here, we discuss how the lifestyle, the availability of suitable in vitro and in vivo systems, and a thorough understanding of the genetics, biochemistry and physiology of the dental pathogen Streptococcus mutans have greatly advanced our understanding of important areas in the field of bacteriology such as interspecies biofilms, competence development and stress responses. In this article, we provide an argument that places S. mutans, an organism that evolved in close association with the human host, as a novel Gram-positive model organism. PMID:23393147

  18. High-level fluorescence labeling of gram-positive pathogens.

    Directory of Open Access Journals (Sweden)

    Simone Aymanns

    Full Text Available Fluorescence labeling of bacterial pathogens has a broad range of interesting applications including the observation of living bacteria within host cells. We constructed a novel vector based on the E. coli streptococcal shuttle plasmid pAT28 that can propagate in numerous bacterial species from different genera. The plasmid harbors a promoterless copy of the green fluorescent variant gene egfp under the control of the CAMP-factor gene (cfb promoter of Streptococcus agalactiae and was designated pBSU101. Upon transfer of the plasmid into streptococci, the bacteria show a distinct and easily detectable fluorescence using a standard fluorescence microscope and quantification by FACS-analysis demonstrated values that were 10-50 times increased over the respective controls. To assess the suitability of the construct for high efficiency fluorescence labeling in different gram-positive pathogens, numerous species were transformed. We successfully labeled Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus dysgalactiae subsp. equisimilis, Enterococcus faecalis, Enterococcus faecium, Streptococcus mutans, Streptococcus anginosus and Staphylococcus aureus strains utilizing the EGFP reporter plasmid pBSU101. In all of these species the presence of the cfb promoter construct resulted in high-level EGFP expression that could be further increased by growing the streptococcal and enterococcal cultures under high oxygen conditions through continuous aeration.

  19. Glycopeptide Resistance in Gram-Positive Cocci: A Review

    Directory of Open Access Journals (Sweden)

    S. Sujatha

    2012-01-01

    Full Text Available Vancomycin-resistant enterococci (VRE have emerged as important nosocomial pathogens in the past two decades all over the world and have seriously limited the choices available to clinicians for treating infections caused by these agents. Methicillin-resistant Staphylococcus aureus, perhaps the most notorious among the nosocomial pathogens, was till recently susceptible to vancomycin and the other glycopeptides. Emergence of vancomycin nonsusceptible strains of S. aureus has led to a worrisome scenario where the options available for treating serious infections due to these organisms are very limited and not well evaluated. Vancomycin resistance in clinically significant isolates of coagulase-negative staphylococci is also on the rise in many setups. This paper aims to highlight the genetic basis of vancomycin resistance in Enterococcus species and S. aureus. It also focuses on important considerations in detection of vancomycin resistance in these gram-positive bacteria. The problem of glycopeptide resistance in clinical isolates of coagulase-negative staphylococci and the phenomenon of vancomycin tolerance seen in some strains of Streptococcus pneumoniae has also been discussed. Finally, therapeutic options available and being developed against these pathogens have also found a mention.

  20. Robenidine Analogues as Gram-Positive Antibacterial Agents.

    Science.gov (United States)

    Abraham, Rebecca J; Stevens, Andrew J; Young, Kelly A; Russell, Cecilia; Qvist, Anastasia; Khazandi, Manouchehr; Wong, Hui San; Abraham, Sam; Ogunniyi, Abiodun D; Page, Stephen W; O'Handley, Ryan; McCluskey, Adam; Trott, Darren J

    2016-03-10

    Robenidine, 1 (2,2'-bis[(4-chlorophenyl)methylene]carbonimidic dihydrazide), was active against MRSA and VRE with MIC's of 8.1 and 4.7 μM, respectively. SAR revealed tolerance for 4-Cl isosteres with 4-F (8), 3-F (9), 3-CH3 (22), and 4-C(CH3)3 (27) (23.7-71 μM) and with 3-Cl (3), 4-CH3 (21), and 4-CH(CH3)2 (26) (8.1-13.0 μM). Imine carbon alkylation identified a methyl/ethyl binding pocket that also accommodated a CH2OH moiety (75; 2,2'-bis[1-(4-chlorophenyl)-2-hydroxyethylidene]carbonimidic dihydrazide). Analogues 1, 27 (2,2'-bis{[4-(1,1-dimethylethyl)phenyl]methylene}carbonimidic dihydrazide), and 69 (2,2'-bis[1-(4-chlorophenyl)ethylidene]carbonimidic dihydrazide hydrochloride) were active against 24 clinical MRSA and MSSA isolates. No dose-limiting cytotoxicity at ≥2× MIC or hemolysis at ≥8× MIC was observed. Polymyxin B addition engendered Escherichia coli and Pseudomonas aeruginosa Gram-negative activity MIC's of 4.2-21.6 μM. 1 and 75 displayed excellent microsomal stability, intrinsic clearance, and hepatic extraction ratios with T1/2 > 247 min, CLint < 7 μL/min/mg protein, and EH < 0.22 in both human and mouse liposomes for 1 and in human liposomes for 75.

  1. Detection and Antibiotic Susceptibility Pattern of Biofilm Producing Gram Positive and Gram Negative Bacteria Isolated From a Tertiary Care Hospital of Pakistan

    Directory of Open Access Journals (Sweden)

    Iqbal, M.

    2011-01-01

    Full Text Available Microorganisms adhere to non-living material or living tissue, and form biofilms made up of extracellular polymers/slime. Biofilm-associated microorganisms behave differently from free-floating bacteria with respect to growth rates and ability to resist antimicrobial treatments and therefore pose a public health problem. The objective of this study is to detect the prevalence of biofilm producers among Gram positive and Gram negative bacteria isolated from clinical specimens, and to study their antimicrobial susceptibility pattern. The study was carried out from October 2009 to March 2010, at the Department of Microbiology, Army Medical College/ National University of Sciences and Technology (NUST, Rawalpindi, Pakistan. Clinical specimens were received from various wards of a tertiary care hospital. These were dealt by standard microbiological procedures. Gram positive and Gram negative bacteria isolated were subjected to biofilm detection by congo red agar method (CRA. Antimicrobial susceptibility testing of those isolates, which showed positive results (slime production, was done according to the Kirby-Bauer disc diffusion technique. A total of 150 isolates were tested for the production of biofilm/slime. Among them, 81 isolates showed positive results. From these 81, 51 were Gram positive and 30 were Gram negative. All the 81(54% slime producers showed reduced susceptibility to majority of antibiotics. Bacterial biofilms are an important virulence factor associated with chronic nosocomial infection. Detection of biofilm forming organisms can help in appropriate antibiotic choice.

  2. Isolation and screening of d-limonene-resistant microorganisms Isolamento e seleção de microrganismos resistentes ao d-Limoneno

    Directory of Open Access Journals (Sweden)

    Juliano Lemos Bicas

    2007-09-01

    bacilos Gram positivos, seguidos por uma menor quantidade de bacilos Gram negativos, leveduras e cocos Gram positivos, além de cinco fungos. Cerca de metade das linhagens de bacilos Gram positivos e Gram negativos e de, leveduras e alguns de cocos Gram positivos resistiram à presença de até 2% de limoneno, dentre as quais 70 foram capazes de sobreviver em ambientes contendo limoneno como única fonte de carbono. O trabalho descrito nesse artigo representa o primeiro passo no desenvolvimento de processos de produção de compostos de aroma pela biotransformação do limoneno.

  3. Lack of clinical utility of urine gram stain for suspected urinary tract infection in pediatric patients.

    Science.gov (United States)

    Cantey, Joseph B; Gaviria-Agudelo, Claudia; McElvania TeKippe, Erin; Doern, Christopher D

    2015-04-01

    Urinary tract infection (UTI) is one of the most common infections in children. Urine culture remains the gold standard for diagnosis, but the utility of urine Gram stain relative to urinalysis (UA) is unclear. We reviewed 312 pediatric patients with suspected UTI who had urine culture, UA, and urine Gram stain performed from a single urine specimen. UA was considered positive if ≥10 leukocytes per oil immersion field were seen or if either nitrates or leukocyte esterase testing was positive. Urine Gram stain was considered positive if any organisms were seen. Sensitivity, specificity, and positive and negative predictive values were calculated using urine culture as the gold standard. Thirty-seven (12%) patients had a culture-proven UTI. Compared to urine Gram stain, UA had equal sensitivity (97.3% versus 97.5%) and higher specificity (85% versus 74%). Empirical therapy was prescribed before the Gram stain result was known in 40 (49%) patients and after in 42 (51%) patients. The antibiotics chosen did not differ between the two groups (P=0.81), nor did they differ for patients with Gram-negative rods on urine Gram stain compared to those with Gram-positive cocci (P=0.67). From these data, we conclude that UA has excellent negative predictive value that is not enhanced by urine Gram stain and that antibiotic selection did not vary based on the urine Gram stain result. In conclusion, the clinical utility of urine Gram stain does not warrant the time or cost it requires. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  4. The Next Generation of Mars-GRAM and Its Role in the Autonomous Aerobraking Development Plan

    Science.gov (United States)

    Justh, Hilary L.; Justus, Carl G.; Ramey, Holly S.

    2011-01-01

    The Mars Global Reference Atmospheric Model (Mars-GRAM) is an engineering-level atmospheric model widely used for diverse mission applications. Mars-GRAM 2010 is currently being used to develop the onboard atmospheric density estimator that is part of the Autonomous Aerobraking Development Plan. In previous versions, Mars-GRAM was less than realistic when used for sensitivity studies for Thermal Emission Spectrometer (TES) MapYear=0 and large optical depth values, such as tau=3. A comparison analysis has been completed between Mars-GRAM, TES and data from the Planetary Data System (PDS) resulting in updated coefficients for the functions relating density, latitude, and longitude of the sun. The adjustment factors are expressed as a function of height (z), Latitude (Lat) and areocentric solar longitude (Ls). The latest release of Mars-GRAM 2010 includes these adjustment factors that alter the in-put data from MGCM and MTGCM for the Mapping Year 0 (user-controlled dust) case. The greatest adjustment occurs at large optical depths such as tau greater than 1. The addition of the adjustment factors has led to better correspondence to TES Limb data from 0-60 km as well as better agreement with MGS, ODY and MRO data at approximately 90-135 km. Improved simulations utilizing Mars-GRAM 2010 are vital to developing the onboard atmospheric density estimator for the Autonomous Aerobraking Development Plan. Mars-GRAM 2010 was not the only planetary GRAM utilized during phase 1 of this plan; Titan-GRAM and Venus-GRAM were used to generate density data sets for Aerobraking Design Reference Missions. These data sets included altitude profiles (both vertical and along a trajectory), GRAM perturbations (tides, gravity waves, etc.) and provided density and scale height values for analysis by other Autonomous Aero-braking team members.

  5. Minimum inhibitory concentrations of herbal essential oils and monolaurin for gram-positive and gram-negative bacteria.

    Science.gov (United States)

    Preuss, Harry G; Echard, Bobby; Enig, Mary; Brook, Itzhak; Elliott, Thomas B

    2005-04-01

    New, safe antimicrobial agents are needed to prevent and overcome severe bacterial, viral, and fungal infections. Based on our previous experience and that of others, we postulated that herbal essential oils, such as those of origanum, and monolaurin offer such possibilities. We examined in vitro the cidal and/or static effects of oil of origanum, several other essential oils, and monolaurin on Staphylococcus aureus, Bacillus anthracis Sterne, Escherichia coli, Klebsiella pneumoniae, Helicobacter pylori, and Mycobacterium terrae. Origanum proved cidal to all tested organisms with the exception of B. anthracis Sterne in which it was static. Monolaurin was cidal to S. aureus and M. terrae but not to E. coli and K. pneumoniae. Unlike the other two gram-negative organisms, H. pylori were extremely sensitive to monolaurin. Similar to origanum, monolaurin was static to B. anthracis Sterne. Because of their longstanding safety record, origanum and/or monolaurin, alone or combined with antibiotics, might prove useful in the prevention and treatment of severe bacterial infections, especially those that are difficult to treat and/or are antibiotic resistant.

  6. Gram-stain-based antimicrobial selection reduces cost and overuse compared with Japanese guidelines.

    Science.gov (United States)

    Taniguchi, Tomohiro; Tsuha, Sanefumi; Shiiki, Soichi; Narita, Masashi

    2015-10-26

    The Gram stain has been used as an essential tool for antimicrobial stewardship in our hospital since the 1970s. The objective of this study was to clarify the difference in the targeted therapies selected based on the Gram stain and simulated empirical therapies based on the antimicrobial guidelines used in Japan. A referral-hospital-based prospective descriptive study was undertaken between May 2013 and April 2014 in Okinawa, Japan. All enrolled patients were adults who had been admitted to the Division of Infectious Diseases through the emergency room with suspected bacterial infection at one of three sites: respiratory system, urinary tract, or skin and soft tissues. The study outcomes were the types and effectiveness of the antibiotics initially selected, and their total costs. Two hundred eight patients were enrolled in the study. The median age was 80 years. A significantly narrower spectrum of antibiotics was selected based on the Gram stain than was selected based on the Japanese guidelines. The treatments based on the Gram stain and on the guidelines were estimated to be equally highly effective. The total cost of antimicrobials after Gram-stain testing was less than half the cost after the guidelines were followed. Compared with the Japanese guidelines, the Gram stain dramatically reduced the overuse of broad-spectrum antimicrobials without affecting the effectiveness of the treatment. Drug costs were reduced by half when the Gram stain was used. The Gram stain should be included in all antimicrobial stewardship programs.

  7. Comparison of Gram stain and Nomarski optics for screening sputum specimens before culture.

    OpenAIRE

    Reimer, L G; Kepas, A

    1986-01-01

    Although the Gram stain is usually used to screen sputum specimens prior to culture, wet mount observation with Nomarski optics has been suggested as a useful alternative. We compared the two methods and found that more specimens were rejected by the Gram stain technique without eliminating any that yielded important clinical information.

  8. A Comparison of Heat versus Methanol Fixation for Gram Staining Bacteria

    Science.gov (United States)

    Minnerath, Jeanne M.; Roland, Jenna M.; Rossi, Lucas C.; Weishalla, Steven R.; Wolf, Melissa M.

    2009-01-01

    Gram staining bacteria is a fundamental technique introduced in general biology and microbiology laboratory courses. Two common problems students encounter when Gram staining bacteria are (1) having a difficult time locating bacterial cells on the microscope slide and (2) over-decolorizing bacterial cells during the staining procedure such that…

  9. Role of Gram-Negative Bacteria and Their Endotoxins in Rat Death after Heat Stress,

    Science.gov (United States)

    1981-02-26

    small volume (0.05 ml) of the homogenate on selective ( MacConkey , Difco, Detroit, MI) and non-selective (5% sheep blood agar) plating media. In...homogenates. Gram-negative bacterial count per gram of duodenal sample was determined from colony counts made from 5 replicate MacConkey plates prepared from

  10. Does the empiric use of vancomycin in pediatrics increase the risk for Gram-negative bacteremia?

    NARCIS (Netherlands)

    Cuno, SPMU; Heesen, GJM; Arends, JP; Kimpen, JLL; van Houten, M.A.

    Background, Gram-negative bacteremia in children, a major cause of morbidity and mortality, may in part be induced by intensive treatment procedures and nonspecific use of antibiotics. Our primary objective was to study the causal relationship between the use of vancomycin and Gram-negative

  11. DMPD: Cellular reprogramming by gram-positive bacterial components: a review. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16885502 Cellular reprogramming by gram-positive bacterial components: a review. Bu...(.csml) Show Cellular reprogramming by gram-positive bacterial components: a review. PubmedID 16885502 Title Cellular reprogramming...ckley JM, Wang JH, Redmond HP. J Leukoc Biol. 2006 Oct;80(4):731-41. Epub 2006 Aug 2. (.png) (.svg) (.html)

  12. Tundmatud kohad ja asjade loomus / Katrine Gram Sloth, Johna Hansen ; intervjueerinud Laura Põld

    Index Scriptorium Estoniae

    Gram Sloth, Katrine, 1983-

    2016-01-01

    Taani kunstnik Katrine Gram Sloth ja Rootsi arhitekt Johna Hansen räägivad oma lapsepõlvest, kunstnikuteest, loomingust. Johna Hanseni jaapanipärasest einelaua installatsioonist "Laud" (2015-2016), Katrine Gram Slothi Islandil loodud teosest "Vista Revisited" (2015)

  13. 40 CFR Table 1 to Subpart A of... - Detection Sensitivity Levels (grams per hour)

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Detection Sensitivity Levels (grams per hour) 1 Table 1 to Subpart A of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Levels (grams per hour) Monitoring frequency per subpart a Detection sensitivity level Bi-Monthly 60 Semi...

  14. A classification system for plasmids from Enterococci and other Gram-positive bacteria

    DEFF Research Database (Denmark)

    Jensen, Lars Bogø; Garcia-Migura, Lourdes; Valenzuela, Antonio Jesus Sanchez

    2010-01-01

    A classification system for plasmids isolated from enterococci and other Gram-positive bacteria was developed based on 111 published plasmid sequences from enterococci and other Gram-positive bacteria; mostly staphylococci. Based on PCR amplification of conserved areas of the replication initiating...

  15. 40 CFR Table 3 to Subpart A of... - Detection Sensitivity Levels (grams per hour)

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Detection Sensitivity Levels (grams per hour) 3 Table 3 to Subpart A of Part 65 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... 3 Table 3 to Subpart A of Part 65—Detection Sensitivity Levels (grams per hour) Monitoring Frequency...

  16. Efficient n-gram, Skipgram and Flexgram Modelling with Colibri Core

    NARCIS (Netherlands)

    Gompel, M. van; Bosch, A.P.J. van den

    2016-01-01

    Counting n-grams lies at the core of any frequentist corpus analysis and is often considered a trivial matter. Going beyond consecutive n-grams to patterns such as skipgrams and flexgrams increases the demand for efficient solutions. The need to operate on big corpus data does so even more. Lossless

  17. Gram-scale fractionation of nanodiamonds by density gradient ultracentrifugation

    Science.gov (United States)

    Peng, Wei; Mahfouz, Remi; Pan, Jun; Hou, Yuanfang; Beaujuge, Pierre M.; Bakr, Osman M.

    2013-05-01

    Size is a defining characteristic of nanoparticles; it influences their optical and electronic properties as well as their interactions with molecules and macromolecules. Producing nanoparticles with narrow size distributions remains one of the main challenges to their utilization. At this time, the number of practical approaches to optimize the size distribution of nanoparticles in many interesting materials systems, including diamond nanocrystals, remains limited. Diamond nanocrystals synthesized by detonation protocols - so-called detonation nanodiamonds (DNDs) - are promising systems for drug delivery, photonics, and composites. DNDs are composed of primary particles with diameters mainly size distribution of various fractions by dynamic light scattering, analytical ultracentrifugation, transmission electron microscopy and powder X-ray diffraction. This fractionation method enabled us to separate gram-scale amounts of DNDs into several size ranges within a relatively short period of time. In addition, the high product yields obtained for each fraction allowed us to apply the fractionation method iteratively to a particular size range of particles and to collect various fractions of highly monodispersed primary particles. Our method paves the way for in-depth studies of the physical and optical properties, growth, and aggregation mechanism of DNDs. Applications requiring DNDs with specific particle or aggregate sizes are now within reach.Size is a defining characteristic of nanoparticles; it influences their optical and electronic properties as well as their interactions with molecules and macromolecules. Producing nanoparticles with narrow size distributions remains one of the main challenges to their utilization. At this time, the number of practical approaches to optimize the size distribution of nanoparticles in many interesting materials systems, including diamond nanocrystals, remains limited. Diamond nanocrystals synthesized by detonation protocols - so

  18. Consumo diario de tabaco en la adolescencia, estados de ánimo negativos y rol de la comunicación familiar Adolescent daily smoking, negative mood-states and the role of family communication

    Directory of Open Access Journals (Sweden)

    Ángel Martínez-Hernáez

    2012-10-01

    Full Text Available Objetivo: Determinar si los estados de ánimo negativos son un factor de riesgo de consumo diario de tabaco en la adolescencia y el papel de los factores familiares en esta asociación. Método: Estudio transversal de una muestra representativa de adolescentes (edad 14-18 años de Cataluña (Segunda Oleada del Panel de Familias e Infancia. Se realizan seis modelos de regresión logística para mujeres (n = 1442 y hombres (n = 1100, con el fin de estimar si los estados de ánimo negativos son un factor de riesgo de consumo diario de cigarrillos. Se estima en qué medida esos efectos son atribuibles a factores familiares. Resultados: La prevalencia de fumadores diarios a los 17/18 años es del 3,8% para las mujeres y del 3,6% para los hombres. El sentimiento de tristeza entre las adolescentes es un factor de riesgo de consumo diario de cigarrillos (odds ratio [OR] = 1,663 y la comunicación con el padre anula este efecto. Sentirse presionados por los progenitores es un factor de riesgo de consumo diario para ambos sexos (mujeres, OR = 2,064; hombres, OR = 1,784, pero al controlar por la variable «comunicación parental» comprobamos que el efecto se reduce, aunque no se anula. Vivir en una familia reconstituida es un factor de riesgo de consumo diario entre los chicos (OR = 2,988. Conclusiones: A igualdad de estados de ánimo, la comunicación intergeneracional atenúa el riesgo de consumo diario de tabaco entre los/las adolescentes. Las intervenciones de prevención y deshabituación tabáquica que incluyan este tipo de factores pueden ser más efectivas.Objective: To determine whether negative mood states constitute a risk factor for daily smoking during adolescence, and to specify the role of familial factors in the association between the two variables. Methods: Cross-sectional study of a representative sample (second wave, Panel of Families and Childhood of Catalan adolescents between 14 and 18 years of age. Six logistic regression models

  19. Gram-scale fractionation of nanodiamonds by density gradient ultracentrifugation

    KAUST Repository

    Peng, Wei

    2013-01-01

    Size is a defining characteristic of nanoparticles; it influences their optical and electronic properties as well as their interactions with molecules and macromolecules. Producing nanoparticles with narrow size distributions remains one of the main challenges to their utilization. At this time, the number of practical approaches to optimize the size distribution of nanoparticles in many interesting materials systems, including diamond nanocrystals, remains limited. Diamond nanocrystals synthesized by detonation protocols-so-called detonation nanodiamonds (DNDs)-are promising systems for drug delivery, photonics, and composites. DNDs are composed of primary particles with diameters mainly <10 nm and their aggregates (ca. 10-500 nm). Here, we introduce a large-scale approach to rate-zonal density gradient ultracentrifugation to obtain monodispersed fractions of nanoparticles in high yields. We use this method to fractionate a highly concentrated and stable aqueous solution of DNDs and to investigate the size distribution of various fractions by dynamic light scattering, analytical ultracentrifugation, transmission electron microscopy and powder X-ray diffraction. This fractionation method enabled us to separate gram-scale amounts of DNDs into several size ranges within a relatively short period of time. In addition, the high product yields obtained for each fraction allowed us to apply the fractionation method iteratively to a particular size range of particles and to collect various fractions of highly monodispersed primary particles. Our method paves the way for in-depth studies of the physical and optical properties, growth, and aggregation mechanism of DNDs. Applications requiring DNDs with specific particle or aggregate sizes are now within reach. © 2013 The Royal Society of Chemistry.

  20. Extended-spectrum ß-lactamases in gram negative bacteria

    Directory of Open Access Journals (Sweden)

    Deepti Rawat

    2010-01-01

    Full Text Available Extended-spectrum ß-lactamases (ESBLs are a group of plasmid-mediated, diverse, complex and rapidly evolving enzymes that are posing a major therapeutic challenge today in the treatment of hospitalized and community-based patients. Infections due to ESBL producers range from uncomplicated urinary tract infections to life-threatening sepsis. Derived from the older TEM is derived from Temoniera, a patient from whom the strain was first isolated in Greece. ß-lactamases, these enzymes share the ability to hydrolyze third-generation cephalosporins and aztreonam and yet are inhibited by clavulanic acid. In addition, ESBL-producing organisms exhibit co-resistance to many other classes of antibiotics, resulting in limitation of therapeutic option. Because of inoculum effect and substrate specificity, their detection is also a major challenge. At present, however, organizations such as the Clinical and Laboratory Standards Institute (formerly the National Committee for Clinical Laboratory Standards provide guidelines for the detection of ESBLs in Klebsiella pneumoniae, K. oxytoca, Escherichia coli and Proteus mirabilis. In common to all ESBL-detection methods is the general principle that the activity of extended-spectrum cephalosporins against ESBL-producing organisms will be enhanced by the presence of clavulanic acid. Carbapenems are the treatment of choice for serious infections due to ESBL-producing organisms, yet carbapenem-resistant isolates have recently been reported. ESBLs represent an impressive example of the ability of gram-negative bacteria to develop new antibiotic-resistance mechanisms in the face of the introduction of new antimicrobial agents. Thus there is need for efficient infection-control practices for containment of outbreaks; and intervention strategies, e.g., antibiotic rotation to reduce further selection and spread of these increasingly resistant pathogens.

  1. Gram-scale fractionation of nanodiamonds by density gradient ultracentrifugation.

    Science.gov (United States)

    Peng, Wei; Mahfouz, Remi; Pan, Jun; Hou, Yuanfang; Beaujuge, Pierre M; Bakr, Osman M

    2013-06-07

    Size is a defining characteristic of nanoparticles; it influences their optical and electronic properties as well as their interactions with molecules and macromolecules. Producing nanoparticles with narrow size distributions remains one of the main challenges to their utilization. At this time, the number of practical approaches to optimize the size distribution of nanoparticles in many interesting materials systems, including diamond nanocrystals, remains limited. Diamond nanocrystals synthesized by detonation protocols - so-called detonation nanodiamonds (DNDs) - are promising systems for drug delivery, photonics, and composites. DNDs are composed of primary particles with diameters mainly <10 nm and their aggregates (ca. 10-500 nm). Here, we introduce a large-scale approach to rate-zonal density gradient ultracentrifugation to obtain monodispersed fractions of nanoparticles in high yields. We use this method to fractionate a highly concentrated and stable aqueous solution of DNDs and to investigate the size distribution of various fractions by dynamic light scattering, analytical ultracentrifugation, transmission electron microscopy and powder X-ray diffraction. This fractionation method enabled us to separate gram-scale amounts of DNDs into several size ranges within a relatively short period of time. In addition, the high product yields obtained for each fraction allowed us to apply the fractionation method iteratively to a particular size range of particles and to collect various fractions of highly monodispersed primary particles. Our method paves the way for in-depth studies of the physical and optical properties, growth, and aggregation mechanism of DNDs. Applications requiring DNDs with specific particle or aggregate sizes are now within reach.

  2. Alterações ultra-sonográficas na gravidez Rh negativo sensibilizada avaliada pela espectrofotometria do líquido amniótico e pela dopplervelocimetria da artéria cerebral média

    Directory of Open Access Journals (Sweden)

    Nardozza Luciano Marcondes Machado

    2006-01-01

    Full Text Available OBJETIVO: Avaliar e confrontar a presença de alterações ultra-sonográficas nas gestações Rh negativo sensibilizadas, quando a anemia fetal foi determinada ou pela espectrofotometria do líquido amniótico, ou pela dopplervelocimetria da artéria cerebral média. MATERIAIS E MÉTODOS: Observacional descritivo com grupo de comparação. Nosso grupo de estudo foi constituído por 99 pacientes, avaliadas no período de janeiro de 1995 a janeiro de 2004. Foram analisados e comparados dois grupos: 74 gestantes sensibilizadas pelo fator Rh cuja anemia fetal foi acompanhada pela espectrofotometria (grupo SE e 25 gestantes sensibilizadas pelo fator Rh cuja anemia fetal foi acompanhada pela dopplervelocimetria (grupo SD. Avaliamos a presença ou não de alterações ultra-sonográficas no acompanhamento pré-natal e confrontamos os dois grupos de estudo. RESULTADOS: No grupo cuja anemia fetal foi acompanhada através da espectrofotometria (grupo SE, apuramos modificações placentárias, principalmente o aumento da espessura e sua alteração textural, mais assiduamente que as encontradiças no grupo de gestantes sensibilizadas, em que a anemia foi determinada através da dopplervelocimetria (grupo SD (64% X 32%, p = 6,294. CONCLUSÃO: As alterações ultra-sonográficas foram detectadas em dobro quando a anemia foi avaliada pela espectrofotometria em comparação com o grupo seguido pela dopplervelocimetria.

  3. Quantification of polysaccharides fixed to Gram stained slides using lactophenol cotton blue and digital image processing.

    Science.gov (United States)

    Ericksen, Bryan

    2015-01-01

    Dark blue rings and circles emerged when the non-specific polysaccharide stain lactophenol cotton blue was added to Gram stained slides. The dark blue staining is attributable to the presence of capsular polysaccharides and bacterial slime associated with clumps of Gram-negative bacteria.  Since all bacterial cells are glycosylated and concentrate polysaccharides from the media, the majority of cells stain light blue. The contrast between dark and light staining is sufficient to enable a digital image processing thresholding technique to be quantitative with little background noise. Prior to the addition of lactophenol cotton blue, the Gram-stained slides appeared unremarkable, lacking ubiquitous clumps or stained polysaccharides.  Adding lactophenol cotton blue to Gram stained slides is a quick and inexpensive way to screen cell cultures for bacterial slime, clumps and biofilms that are invisible using the Gram stain alone.

  4. Comparison of routine urinalysis and urine Gram stain for detection of bacteriuria in dogs.

    Science.gov (United States)

    Way, Leilani Ireland; Sullivan, Lauren A; Johnson, Valerie; Morley, Paul S

    2013-01-01

    To determine the utility of performing urine Gram stain for detection of bacteriuria compared to routine urine sediment examination and bacterial aerobic urine culture. Prospective, observational study. University teaching hospital. Urine samples acquired via cystocentesis through convenience sampling from 103 dogs presenting to a tertiary referral institution. All samples underwent routine urinalysis, including sediment examination, as well as urine Gram stain and quantitative bacterial aerobic urine culture. The urine Gram stain demonstrated improved sensitivity (96% versus 76%), specificity (100% versus 77%), positive predictive value (100% versus 83%), and negative predictive value (93% versus 69%) when identifying bacteriuria, compared to routine urine sediment examination. The urine Gram stain is highly sensitive and specific when detecting the presence of bacteria in canine urine samples. Gram staining should be considered when bacteriuria is highly suspected and requires rapid identification while bacterial culture is pending. © Veterinary Emergency and Critical Care Society 2013.

  5. Nutritional and functional evaluation of wheat flour cookies supplemented with gram flour.

    Science.gov (United States)

    Yousaf, Ali A; Ahmed, Anwaar; Ahmad, Asif; Hameed, Tabassum; Randhawa, Muhammad Atif; Hayat, Imran; Khalid, Nauman

    2013-02-01

    Protein-enriched cookies were prepared by supplementing gram flour into wheat flour at levels of 0%, 10%, 20%, 30%, 40% and 50% and analysed for physicochemical properties. The protein quality of the cookies was assessed by feeding gram flour-supplemented cookies to albino rats for 10 days. The supplementation resulted in a significant increase in protein, fat, crude fibre and ash contents of the cookies. The thickness and spread factor of cookies differ significantly while non-significant effect was observed in the width of the cookies. The protein efficiency ratio, net protein utilization, biological value and true digestibility differed significantly among diets containing cookies with gram flour fed to rats. Cookies with 30% substitution of straight grade flour and gram flour produced acceptable cookies as compared to control. The cookies containing 40-50% gram flour were best regarded as protein bioavailability for rats.

  6. Predatory bacteria: a potential ally against multidrug-resistant Gram-negative pathogens.

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    Daniel E Kadouri

    Full Text Available Multidrug-resistant (MDR Gram-negative bacteria have emerged as a serious threat to human and animal health. Bdellovibrio spp. and Micavibrio spp. are Gram-negative bacteria that prey on other Gram-negative bacteria. In this study, the ability of Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus to prey on MDR Gram-negative clinical strains was examined. Although the potential use of predatory bacteria to attack MDR pathogens has been suggested, the data supporting these claims is lacking. By conducting predation experiments we have established that predatory bacteria have the capacity to attack clinical strains of a variety of ß-lactamase-producing, MDR Gram-negative bacteria. Our observations indicate that predatory bacteria maintained their ability to prey on MDR bacteria regardless of their antimicrobial resistance, hence, might be used as therapeutic agents where other antimicrobial drugs fail.

  7. Gram-negative folliculitis. A rare problem or is it underdiagnosed? Case report and literature review

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    Sierra-Téllez Daniela, Ponce-Olivera Rosa María, Tirado-Sánchez Andrés

    2011-07-01

    Full Text Available AbstractGram-negative folliculitis may be the result of prolonged antibacterial treatments in patients with acne and rosacea. It is caused by alteration of facial skin flora and the nasal mucous, a decrease of Gram-positive bacteria and a proliferation of Gram-negative bacteria (for example Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens, Klebsiella sp. and Proteus mirabilis. It should be considered in patients with acne who have not had a clinical improvement after 3-6 months of treatment with tetracyclines. The disease is underestimated, probably because bacteriological studies are rarely requested and the increased use of oral isotretinoin for acne management. One of the most effective treatments for Gram-negative folliculitis is oral isotretinoin (0.5-1 mg / kg / day for 4-5 months. We report the case of Gram negative folliculitis successfully treated with oral isotretinoin.

  8. Febre maculosa das Montanhas Rochosas: ensaios negativos de transmissão experimental do virus por Triatomideos Rocky Mountain spotted fever: failure of Triatomid bugs to transmit the virus experimentally

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    Cornelius B. Philip

    1938-01-01

    Full Text Available 1. - As seguintes especies de Triatomideos não puderam transmitir pela picada o virus da febre maculosa das Montanhas Rochosas a cobayas normaes, nos seguintes prazos após a sucção de animal infectado: Eutriatoma uhleri, 33, 47, 75 e 141 dias (1 exemplar; Triatoma protracta, 15 e 37 dias (1 exemplar, Triatoma infestans, 8 dias (15 exemplares, e Rhodnius prolixus, 2 dias (1 exemplar. Foi demonstrado por inoculaçao que o ultimo insecto ainda continha o virus vivo. 2. - Experiencias de transmissão mechanica, por picada interrompida em animal infectado e continuada immediatamente em animal são, foram tambem negativas, com as especies T. protracta e R. prolixus. Um unico insecto da primeira especie picou 2 vezes cada animal, emquanto que 22 exemplares da segunda especie picaram de 1 a 3 vezes cada cobaya. 3. - A inoculação de gottas de dejecções de um R. prolixus eliminadas 2 dias depois de sugar animal infectado, não produziu a infecção em cobaya normal, não obstante ter sido demonstrada a presença do virus no organismo do barbeiro, por inoculação do conteúdo estomacal em outra cobaya. 4. - Foram feitas experiencias para determinar o tempo de sobrevivencia do virus nos barbeiros, inoculando-se conteúdo intestinal a diversos intervallos depois da sucção de cobayas infectadas, com os seguintes resultados: T. infestans: positivo 1 vez em 24 horas e 2 vezes em 48 horas; negativo 2 vezes em 72. 96, 120 e 192 horas. P. megistus: positivo 3 vezes em 24 horas, 2 vezes em 48 horas e 1 vez em 72 horas; negativo 1 vez em 72 e 96 horas; resultado duvidoso ou sem valor (infecção intercorrente 1 vez em 48 horas e 2 vezes a 72, 96 e 144 horas cada um. R. prolixus: positivo 1 vez em 24, 48 e 72 horas e negativo em 96 horas. 5. - Em vista dos resultados destas experiencias, feitas com 5 especies pertecentes a 4 generos de Triatomideos, torna-se muito pouco provavel que estes Hemipteros possam transmitir pela picada o virus da febre maculosa

  9. A prospective study of the diagnostic utility of sputum Gram stain in pneumonia.

    Science.gov (United States)

    Anevlavis, Stavros; Petroglou, Niki; Tzavaras, Athanasios; Maltezos, Efstratios; Pneumatikos, Ioannis; Froudarakis, Marios; Anevlavis, Eleftherios; Bouros, Demosthenes

    2009-08-01

    Sputum Gram stain and culture have been said to be unreliable indicators of the microbiological diagnosis of bacterial pneumonia. The etiological diagnosis of pneumonia is surrounded by great degree of uncertainty. This uncertainty should be and can be calculated and incorporated in the diagnosis and treatment. To determine the diagnostic accuracy and diagnostic value of sputum Gram stain in etiological diagnosis and initial selection of antimicrobial therapy of bacterial community acquired pneumonia (CAP). DESIGN-METHOD: Prospective study of 1390 patients with CAP admitted January 2002-June 2008, to our institutions. Of the 1390 patients, 178 (12.8%) fulfilled the criteria for inclusion into this study (good-quality sputa and presence of the same microorganism in blood and sputum cultures which was used as gold standard for assessing the diagnostic accuracy and diagnostic value of sputum Gram stain). The sensitivity of sputum Gram stain was 0.82 for Pneumococcal pneumonia, 0.76 for Staphylococcal pneumonia, 0.79 for Haemophilus influenzae pneumonia and 0.78 for Gram-negative bacilli pneumonia. The specificity of sputum Gram stain was 0.93 for Pneumococcal pneumonia, 0.96 for Staphylococcal pneumonia, 0.96 for H. influenzae pneumonia and 0.95 for Gram-negative bacilli pneumonia. The positive likelihood ratio (LR+) was 11.58 for Pneumococcal pneumonia, 19.38 for Staphylococcal pneumonia, 16.84 for H. influenzae pneumonia, 14.26 for Gram-negative bacilli pneumonia. The negative likelihood ratio (LR-) was 0.20 for Pneumococcal pneumonia, 0.25 for Staphylococcal pneumonia, 0.22 for H. influenzae pneumonia, and 0.23 for Gram-negative bacilli pneumonia. Sputum Gram stain is a dependable diagnostic test for the early etiological diagnosis of bacterial CAP that helps in choosing orthological and appropriate initial antimicrobial therapy.

  10. Should gram stains have a role in diagnosing hip arthroplasty infections?

    Science.gov (United States)

    Johnson, Aaron J; Zywiel, Michael G; Stroh, D Alex; Marker, David R; Mont, Michael A

    2010-09-01

    The utility of Gram stains in diagnosing periprosthetic infections following total hip arthroplasty has recently been questioned. Several studies report low sensitivity of the test, and its poor ability to either confirm or rule out infection in patients undergoing revision total hip arthroplasty. Despite this, many institutions including that of the senior author continue to perform Gram stains during revision total hip arthroplasty. We assessed the sensitivity, specificity, accuracy, and positive and negative predictive values of Gram stains from surgical-site samplings taken from procedures on patients with both infected and aseptic revision total hip arthroplasties. A review was performed on patients who underwent revision total hip arthroplasty between 2000 and 2007. Eighty-two Gram stains were performed on patients who had infected total hip arthroplasties and underwent revision procedures. Additionally, of the 410 revision total hip arthroplasties performed on patients who were confirmed infection-free, 120 Gram stains were performed. Patients were diagnosed as infected using multiple criteria at the time of surgery. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated from these Gram stain results. The Gram stain demonstrated a sensitivity and specificity of 9.8% and 100%, respectively. In this series, the Gram stain had a negative predictive value of 62%, a positive predictive value of 100%, and an accuracy of 63%. Gram stains obtained from surgical-site samples had poor sensitivity and poor negative predictive value. Based on these findings, as well as those of other authors, we believe that Gram stains should no longer be considered for diagnosing infections in revision total hip arthroplasty. Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

  11. Avaliação da atividade in vitro dos novos antimicrobianos da classe das fluoroquinolonas, cefalosporinas e carbapenens contra 569 amostras clínicas de bactérias gram-negativas

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    Gales A.C.

    1997-01-01

    Full Text Available OBJETIVO. A proposta deste estudo foi a avaliação da atividade in vitro de novos antimicrobianos da classe das fluoroquinolonas, das cefalosporinas e dos carbapenens contra bactérias gram-negativas. MATERIAL E MÉTODO. Foram avaliadas 569 amostras clínicas isoladas no Hospital São Paulo - UNIFESP/EPM, no período compreendido entre junho e julho de 1992. A distribuição das espécies foi: Enterobacter sp. (62, Escherichia coli (308, Klebsiella pneumoniae (27, Klebsiella sp. (9, Proteus mirabilis (23, Pseudomonas aeruginosa (88, Pseudomonas sp. (4, Serratia sp. (30 e outros gram-negativos (7. Os testes de sensibilidade aos antimicrobianos avaliados (ciprofloxacina, ofloxacina, levofloxacina, grepafloxacina, DU 6859-a, ceftazidima, cefepima, FK 037, imipenem, meropenem e biapenem foram realizados pela técnica de microdiluição em caldo. RESULTADOS. A fluoroquinolona mais potente foi a DU 6859-a; em algumas amostras, apresentou potência duas a quatro vezes superior àquela apresentada pela ciprofloxacina. As novas cefalosporinas de 4ª geração apresentaram potência e espectro de ação semelhantes nas amostras de Enterobacteriaceae, com exceção das amostras de Enterobacter sp., para as quais a cefepima foi mais ativa, e das amostras de P. aeruginosa, para as quais a cefalosporina mais potente e com maior percentagem de suscetibilidade foi a ceftazidima. O meropenem foi o carbapenem mais potente e com maior percentagem de suscetibilidade nas amostras estudadas. CONCLUSÃO. As novas drogas apresentaram, em geral, melhor atividade in vitro do que drogas da mesma classe já utilizadas na prática clínica. Porém, mais estudos serão necessários para avaliar a atividade in vivo desses agentes e sua real utilidade clínica.

  12. Pleural effusion adenosine deaminase: a candidate biomarker to discriminate between Gram-negative and Gram-positive bacterial infections of the pleural space

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    Ruolin Li

    2016-05-01

    Full Text Available OBJECTIVES: Delay in the treatment of pleural infection may contribute to its high mortality. In this retrospective study, we aimed to evaluate the diagnostic accuracy of pleural adenosine deaminase in discrimination between Gram-negative and Gram-positive bacterial infections of the pleural space prior to selecting antibiotics. METHODS: A total of 76 patients were enrolled and grouped into subgroups according to Gram staining: 1 patients with Gram-negative bacterial infections, aged 53.2±18.6 years old, of whom 44.7% had empyemas and 2 patients with Gram-positive bacterial infections, aged 53.5±21.5 years old, of whom 63.1% had empyemas. The pleural effusion was sampled by thoracocentesis and then sent for adenosine deaminase testing, biochemical testing and microbiological culture. The Mann-Whitney U test was used to examine the differences in adenosine deaminase levels between the groups. Correlations between adenosine deaminase and specified variables were also quantified using Spearman’s correlation coefficient. Moreover, receiver operator characteristic analysis was performed to evaluate the diagnostic accuracy of pleural effusion adenosine deaminase. RESULTS: Mean pleural adenosine deaminase levels differed significantly between Gram-negative and Gram-positive bacterial infections of the pleural space (191.8±32.1 U/L vs 81.0±16.9 U/L, p<0.01. The area under the receiver operator characteristic curve was 0.689 (95% confidence interval: 0.570, 0.792, p<0.01 at the cutoff value of 86 U/L. Additionally, pleural adenosine deaminase had a sensitivity of 63.2% (46.0-78.2%; a specificity of 73.7% (56.9-86.6%; positive and negative likelihood ratios of 2.18 and 0.50, respectively; and positive and negative predictive values of 70.6% and 66.7%, respectively. CONCLUSIONS: Pleural effusion adenosine deaminase is a helpful alternative biomarker for early and quick discrimination of Gram-negative from Gram-positive bacterial infections of the

  13. Host susceptibility to gram-negative pneumonia after lung contusion.

    Science.gov (United States)

    Dolgachev, Vladislav A; Yu, Bi; Reinke, Julia M; Raghavendran, Krishnan; Hemmila, Mark R

    2012-03-01

    Lung contusion (LC) induces inflammation with high local concentrations of proinflammatory mediators stimulating chemotaxis and activation of neutrophils. LC is also a risk factor for development of pneumonia; however, the reason for this increased susceptibility is not clearly identified. We hypothesize that LC creates acute changes in the host pulmonary innate immune system that leads to vulnerability from a "second" hit bacterial infection. Female C57Bl/6 mice underwent LC injury at time -6 hours. At 0 hours, these mice were inoculated intratracheally with 1,000 colony forming unit (CFU) of Klebsiella pneumoniae (LC+Pneu) or vehicle (LC). Control animals underwent a sham LC injury followed by pneumonia (Sham+Pneu). Bronchoalveolar lavage (BAL) fluid and lung tissue specimens were collected. Lung bacteria levels were quantified by serial dilution, plating, and counting CFUs. Cytokine levels were assayed by ELISA. Cell type identification and quantification was performed using flow cytometry. Survival at 72 hours was markedly different for the LC, Sham+Pneu, and LC+Pneu groups (100%, 80%, 20%, p Pneu vs. LC+Pneu). LC+Pneu animals had decreased pulmonary bacterial clearance at 24 hours compared with the Sham+Pneu group (4 × 10(7) vs. 8 × 10(6) CFUs, p Pneu mice compared with the Sham+Pneu group at 24 hours. Conversely, the Sham+Pneu mice had increased levels of macrophage inflammatory protein-2, total cells, macrophages, and neutrophils in BAL compared with the LC+Pneu group at 24 hours. LC+Pneu animals demonstrated changes in macrophage apoptosis and necrosis in BAL samples obtained 2 hours after induction of pneumonia when compared with the Sham+Pneu group. Both Sham+Pneu and LC+Pneu animals demonstrated an increase in the level of IL-10 in BAL fluid compared with LC animals. Acute inflammation after LC acts to modulate the presence of inflammatory cells necessary to combat gram-negative bacteria. This results in decreased bacterial clearance and increased

  14. Resistance trends in gram-negative bacteria: surveillance results from two Mexican hospitals, 2005–2010

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    Morfin-Otero Rayo

    2012-06-01

    Full Text Available Abstract Background Hospital-acquired infections caused by multiresistant gram-negative bacteria are difficult to treat and cause high rates of morbidity and mortality. The analysis of antimicrobial resistance trends of gram-negative pathogens isolated from hospital-acquired infections is important for the development of antimicrobial stewardship programs. The information obtained from antimicrobial resistant programs from two hospitals from Mexico will be helpful in the selection of empiric therapy for hospital-acquired gram-negative infections. Findings Two thousand one hundred thirty two gram-negative bacteria collected between January 2005 and December 2010 from hospital-acquired infections occurring in two teaching hospitals in Mexico were evaluated. Escherichia coli was the most frequently isolated gram-negative bacteria, with >50% of strains resistant to ciprofloxacin and levofloxacin. Klebsiella spp. showed resistance rates similar to Escherichia coli for ceftazidime (33.1% vs 33.2%, but exhibited lower rates for levofloxacin (18.2% vs 56%. Of the samples collected for the third most common gram-negative bacteria, Pseudomonas aeruginosa, >12.8% were resistant to the carbapenems, imipenem and meropenem. The highest overall resistance was found in Acinetobacter spp. Enterobacter spp. showed high susceptibility to carbapenems. Conclusions E. coli was the most common nosocomial gram-negative bacilli isolated in this study and was found to have the second-highest resistance to fluoroquinolones (>57.9%, after Acinetobacter spp. 81.2%. This finding represents a disturbing development in a common nosocomial and community pathogen.

  15. Analysis of the utility of stone gram stain in urolithiasis treated with percutaneous nephrolithotomy.

    Science.gov (United States)

    Cockerill, Patrick A; Rivera, Marcelino E; Krambeck, Amy E

    2014-06-01

    To define the sensitivity and specificity of stone gram stain for infected urolithiasis treated with percutaneous nephrolithotomy (PCNL). PCNL procedures performed at our institution were analyzed between January 2009 and May 2013. Stone fragments were sent in a sterile fashion for aerobic and fungal cultures. A gram stain and fungal smear were performed on the stones and reported within 24 hours of collection. A total of 228 patients underwent 248 PCNLs. Of the 248 stones, 81 (33%) had a positive stone culture. Stone gram stain was positive in 31 cases and negative in 50. There were 167 negative stone cultures, and in these cases, gram stain was positive in 5 and negative in 162. The calculated sensitivity and specificity of stone gram stain were 38% and 97%. The positive and negative predictive values were 86% and 76%, respectively. In the subset of 16 patients with positive stone fungal cultures, fungal smear was performed in 12 and was positive in 4, giving fungal smear a sensitivity of 33%. The results of this study suggest that stone gram stain cannot be relied on to detect a positive stone culture and may fail to detect up to 62% of infected stones. However, when positive, gram stain accurately predicts a positive stone culture in 86% of cases. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Improving Gram stain proficiency in hospital and satellite laboratories that do not have microbiology.

    Science.gov (United States)

    Guarner, Jeannette; Street, Cassandra; Matlock, Margaret; Cole, Lisa; Brierre, Francoise

    2017-03-01

    Consolidation of laboratories has left many hospitals and satellite laboratories with minimal microbiologic testing. In many hospitals and satellite laboratories, Gram stains on primary specimens are still performed despite difficultly in maintaining proficiency. To maintain Gram stain proficiency at a community 450-bed hospital with an active emergency room we designed bimonthly challenges that require reporting Gram staining and morphology of different organisms. The challenges consist of five specimens prepared by the reference microbiology laboratory from cultures and primary specimens. Twenty to 23 medical laboratory scientists participate reading the challenges. Results from the challenges are discussed with each medical laboratory scientists. In addition, printed images from the challenges are presented at huddle to add microbiology knowledge. On the first three challenges, Gram staining was read correctly in 71%-77% of the time while morphology 53%-66%. In the last six challenges correct answers for Gram stain were 77%-99% while morphology 73%-96%. We observed statistically significant improvement when reading Gram stains by providing frequent challenges to medical laboratory scientists. The clinical importance of Gram stain results is emphasized during huddle presentations increasing knowledge and motivation to perform the test for patients.

  17. The NASA/MSFC Global Reference Atmospheric Model: 1999 Version (GRAM-99)

    Science.gov (United States)

    Justus, C. G.; Johnson, D. L.

    1999-01-01

    The latest version of Global Reference Atmospheric Model (GRAM-99) is presented and discussed. GRAM-99 uses either (binary) Global Upper Air Climatic Atlas (GUACA) or (ASCII) Global Gridded Upper Air Statistics (GGUAS) CD-ROM data sets, for 0-27 km altitudes. As with earlier versions, GRAM-99 provides complete geographical and altitude coverage for each month of the year. GRAM-99 uses a specially-developed data set, based on Middle Atmosphere Program (MAP) data, for 20-120 km altitudes, and NASA's 1999 version Marshall Engineering Thermosphere (MET-99) model for heights above 90 km. Fairing techniques assure smooth transition in overlap height ranges (20-27 km and 90-120 km). GRAM-99 includes water vapor and 11 other atmospheric constituents (O3, N2O, CO, CH4, CO2, N2, O2, O, A, He and H). A variable-scale perturbation model provides both large-scale (wave) and small-scale (stochastic) deviations from mean values for thermodynamic variables and horizontal and vertical wind components. The small-scale perturbation model includes improvements in representing intermittency ("patchiness"). A major new feature is an option to substitute Range Reference Atmosphere (RRA) data for conventional GRAM climatology when a trajectory passes sufficiently near any RRA site. A complete user's guide for running the program, plus sample input and output, is provided. An example is provided for how to incorporate GRAM-99 as subroutines in other programs (e.g., trajectory codes).

  18. Extruded black gram flour: Partial substitute for improving quality characteristics of Indian traditional snack

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    Laxmi Ananthanarayan

    2018-03-01

    Full Text Available Background: During extrusion of black gram flour, formation of amylose-lipid complexes lowers down the gelatinization enthalpy of extrudates, and the partially gelatinized black gram starch leads to lowering down the water-holding capacity and alters functional properties resulting in changing quality attributes of the end product on frying/microwaving/roasting. Methods: Attempts have been made to improve the quality of an Indian traditional snack (e.g., papad by incorporating extruded black gram flour as partial substitute for raw (unextruded black gram flour. In present work, overall quality improvement was achieved by analyzing prefrying and postfrying characteristics (diameter, moisture content, expansion ratio, oil uptake, texture, and color of papad and physical properties (color and viscosity of fried oil. Results: Four different papad samples were prepared (control papads without addition of papadkhar, papads with use of 3% papadkhar, papads with incorporation of extruded black gram flour at 25% concentration, papads with incorporation of extruded black gram flour at 50% concentration along with 1% papadkhar and analyzed along standard market sample. Incorporation of extruded black gram flour in papad resulted in greater expansion with less oil uptake in fried papad. Further addition of extruded black gram flour permitted the use of lower concentration of papadkhar. After frying, the quality of oil was characterized after numerous frying cycles. Conclusion: Oil used for frying of papads containing highest concentration of papadkhar was effective only up to two frying cycles, after which color and viscosity increased significantly, adversely affecting the quality of fried oil. Keywords: Black gram flour, Extrusion, Prefrying and postfrying characteristics of papad, Quality of fried oil

  19. Evaluation of the in vitro growth of urinary tract infection-causing gram-negative and gram-positive bacteria in a proposed synthetic human urine (SHU) medium.

    Science.gov (United States)

    Ipe, Deepak S; Ulett, Glen C

    2016-08-01

    Bacteriuria is a hallmark of urinary tract infection (UTI) and asymptomatic bacteriuria (ABU), which are among the most frequent infections in humans. A variety of gram-negative and gram-positive bacteria are associated with these infections but Escherichia coli contributes up to 80% of cases. Multiple bacterial species including E. coli can grow in human urine as a means to maintain colonization during infections. In vitro bacteriuria studies aimed at modeling microbial growth in urine have utilized various compositions of synthetic human urine (SHU) and a Composite SHU formulation was recently proposed. In this study, we sought to validate the recently proposed Composite SHU as a medium that supports the growth of several bacterial species that are known to grow in normal human urine and/or artificial urine. Comparative growth assays of gram-negative and gram-positive bacteria E. coli, Pseudomonas aeruginosa, Proteus mirabilis, Streptococcus agalactiae, Staphylococcus saprophyticus and Enterococcus faecalis were undertaken using viable bacterial count and optical density measurements over a 48h culture period. Three different SHU formulations were tested in various culture vessels, shaking conditions and volumes and showed that Composite SHU can support the robust growth of gram-negative bacteria but requires supplementation with 0.2% yeast extract to support the growth of gram-positive bacteria. Experiments are also presented that show an unexpected but major influence of P. mirabilis towards the ability to measure bacterial growth in generally accepted multiwell assays using absorbance readings, predicted to have a basis in the release of volatile organic compound(s) from P. mirabilis during growth in Composite SHU medium. This study represents an essential methodological validation of a more chemically defined type of synthetic urine that can be applied to study mechanisms of bacteriuria and we conclude will offer a useful in vitro model to investigate the

  20. Bactericidal Efficacy of Hydrogen Peroxide-Based Disinfectants Against Gram-Positive and Gram-Negative Bacteria on Stainless Steel Surfaces.

    Science.gov (United States)

    Ríos-Castillo, Abel G; González-Rivas, Fabián; Rodríguez-Jerez, José J

    2017-10-01

    In order to develop disinfectant formulations that leverage the effectiveness of hydrogen peroxide (H 2 O 2 ), this study evaluated the bactericidal efficacy of hydrogen peroxide-based disinfectants against Gram-positive and Gram-negative bacteria on stainless steel surfaces. Low concentration of hydrogen peroxide as 0.5% with a cationic polymer, ethoxylated fatty alcohol, and ethyl alcohol had bactericidal efficacy (reductions ≥ 4 log 10 CFU/mL) against Escherichia coli, Staphylococcus aureus, Enterococcus hirae, and Pseudomonas aeruginosa. Hydrogen peroxide-based disinfectants were more effective against E. hirae and P. aeruginosa than to S. aureus. However, the efficacy of hydrogen peroxide against catalase positive bacteria such as S. aureus was increased when this compound was formulated with low concentrations of benzalkonium chloride or ethyl alcohol, lactic acid, sodium benzoate, cationic polymer, and salicylic acid. This study demonstrates that the use of hydrogen peroxide with other antimicrobial products, in adequate concentrations, had bactericidal efficacy in Gram-positive and Gram-negative bacteria on stainless steel surfaces, enabling to reduce the effective concentration of hydrogen peroxide. In the same way, the use of hydrogen peroxide-based disinfectants could reduce the concentrations of traditional disinfectants as quaternary ammonium compounds and therefore a reduction of their chemical residues in the environment after being used. The study of the bactericidal properties of environmentally nontoxic disinfectants such as hydrogen peroxide, sole or in formulations with other disinfectants against Gram-positive and Gram-negative bacteria can enhance the efficacy of various commonly used disinfectant formulations with the hygiene benefits that it entails. Also, the use of hydrogen peroxide formulations can reduce the concentration levels of products that generate environmental residues. © 2017 Institute of Food Technologists®.

  1. Clinical Utility of an Automated Instrument for Gram Staining Single Slides ▿

    Science.gov (United States)

    Baron, Ellen Jo; Mix, Samantha; Moradi, Wais

    2010-01-01

    Gram stains of 87 different clinical samples were prepared by the laboratory's conventional methods (automated or manual) and by a new single-slide-type automated staining instrument, GG&B AGS-1000. Gram stains from either heat- or methanol-fixed slides stained with the new instrument were easy to interpret, and results were essentially the same as those from the methanol-fixed slides prepared as a part of the routine workflow. This instrument is well suited to a rapid-response laboratory where Gram stain requests are commonly received on a stat basis. PMID:20410348

  2. Clinical utility of an automated instrument for gram staining single slides.

    Science.gov (United States)

    Baron, Ellen Jo; Mix, Samantha; Moradi, Wais

    2010-06-01

    Gram stains of 87 different clinical samples were prepared by the laboratory's conventional methods (automated or manual) and by a new single-slide-type automated staining instrument, GG&B AGS-1000. Gram stains from either heat- or methanol-fixed slides stained with the new instrument were easy to interpret, and results were essentially the same as those from the methanol-fixed slides prepared as a part of the routine workflow. This instrument is well suited to a rapid-response laboratory where Gram stain requests are commonly received on a stat basis.

  3. Strategies to Improve the Accuracy of Mars-GRAM Sensitivity Studies at Large Optical Depths

    Science.gov (United States)

    Justh, Hilary L.; Justus, Carl G.; Badger, Andrew M.

    2010-01-01

    The poster provides an overview of techniques to improve the Mars Global Reference Atmospheric Model (Mars-GRAM) sensitivity. It has been discovered during the Mars Science Laboratory (MSL) site selection process that the Mars Global Reference Atmospheric Model (Mars-GRAM) when used for sensitivity studies for TES MapYear = 0 and large optical depth values such as tau = 3 is less than realistic. A preliminary fix has been made to Mars-GRAM by adding a density factor value that was determined for tau = 0.3, 1 and 3.

  4. Earth Global Reference Atmospheric Model (GRAM) Overview and Updates: DOLWG Meeting

    Science.gov (United States)

    White, Patrick

    2017-01-01

    What is Earth-GRAM (Global Reference Atmospheric Model): Provides monthly mean and standard deviation for any point in atmosphere - Monthly, Geographic, and Altitude Variation; Earth-GRAM is a C++ software package - Currently distributed as Earth-GRAM 2016; Atmospheric variables included: pressure, density, temperature, horizontal and vertical winds, speed of sound, and atmospheric constituents; Used by engineering community because of ability to create dispersions in atmosphere at a rapid runtime - Often embedded in trajectory simulation software; Not a forecast model; Does not readily capture localized atmospheric effects.

  5. Effect of gamma radiation on physico-chemical characteristics of red gram (Cajanus cajan) starch

    International Nuclear Information System (INIS)

    Nene, S.P.; Vakil, U.K.; Sreenivasan, A.

    1975-01-01

    Total reducing and nonreducing sugars in red gram (Cajanus cajan) are not affected by radiation treatment (1 Mrad). Oligosaccharides, reported as flatulence factors in legumes, namely stachyose and raffinose, are slightly decreased on cooking the irradiated samples. Irradiated and cooked red gram starch is more susceptible to alpha-amylase action than the unirradiated sample. Rheological properties of red gram starch, such as gelatinization viscosity, swelling power and solubility improve on irradiation resulting in a final cooked product with better textural properties. (U.S.)

  6. Physico-Chemical-Managed Killing of Penicillin-Resistant Static and Growing Gram-Positive and Gram-Negative Vegetative Bacteria

    Science.gov (United States)

    Richmond, Robert Chaffee (Inventor); Schramm, Jr., Harry F. (Inventor); Defalco, Francis G. (Inventor); Farris, III, Alex F. (Inventor)

    2012-01-01

    Systems and methods for the use of compounds from the Hofmeister series coupled with specific pH and temperature to provide rapid physico-chemical-managed killing of penicillin-resistant static and growing Gram-positive and Gram-negative vegetative bacteria. The systems and methods represent the more general physico-chemical enhancement of susceptibility for a wide range of pathological macromolecular targets to clinical management by establishing the reactivity of those targets to topically applied drugs or anti-toxins.

  7. Aspectos positivos e negativos da esterilização tubária do ponto de vista de mulheres esterilizadas Positive and negative aspects of Fallopian tube sterilization as viewed by sterilized women

    Directory of Open Access Journals (Sweden)

    Luzinete Simões Minella

    1998-01-01

    Full Text Available O objetivo deste artigo consiste em tratar os aspectos positivos e negativos da esterilização feminina, de acordo com o ponto de vista de dois grupos de mulheres esterilizadas em Florianópolis, Santa Catarina, Brasil, a partir de uma discussão sociológica sobre o seu estado de saúde atual, avaliando-se as relações que costumam fazer entre este estado e a condição de esterilizada. O primeiro grupo está constituído por mulheres provenientes de um bairro de baixa renda, predominantemente donas de casa, e o segundo grupo inclui funcionárias públicas, estudantes e professoras universitárias, provenientes dos setores médios da sociedade, totalizando quarenta mulheres. A metodologia da pesquisa baseou-se em um questionário estruturado com perguntas abertas de modo a registrar tanto aspectos ligados a variáveis sócio-econômicas e demográficas, quanto dados subjetivos ligados às representações das mulheres sobre o período pós-esterilização. Além de uma série de outros aspectos, tornou-se possível concluir que não existe consenso sobre as conseqüências da esterilização, tendo-se constatado a existência de uma proporção significativa de mulheres esterilizadas (11 principalmente antes dos 30 anos que percebem alterações de saúde após a laqueadura.The objective of this paper is to point out the positive and negative aspects of female sterilization as seen by two groups of sterilized women in Florianópolis, Santa Catarina, Brazil, based on a sociological discussion of their present health status, evaluating the associations that they generally make with the fact that they have been sterilized. The first group included mostly housewives from a low-income neighborhood, while the second involved upper-middle-class female public employees, students, and university professors, totaling 40 women. Data were obtained through a structured questionnaire with open-ended questions. Information on social, economic, and

  8. Significância clínica, epidemiologia e microbiologia das bacteremias por estafilococos coagulase-negativos em Hospital de Ensino Clinical significance, epidemiology and microbiology of coagulase-negative staphylococcal nosocomial bacteremia at a teaching hospital

    Directory of Open Access Journals (Sweden)

    F. Góngora-Rubio

    1997-03-01

    Full Text Available Os estafilococos coagulase-negativos (ECN são importantes agentes etiológicos das bacteremias hospitalares e freqüentemente considerados como contaminantes de hemoculturas. No período de outubro de 1990 a setembro de 1992, foram estudadas 300 hemoculturas positivas para ECN no Hospital São Paulo, sendo 141 bacteremias consideradas de origem hospitalar. Com o objetivo de diferenciar as bacteremias hospitalares verdadeiras das contaminantes por ECN, foram definidos critérios clínicos e microbiológicos. Apenas 20,6% das bacteremias hospitalares por ECN foram consideradas como verdadeiras. A maior freqüência de recém-nascidos internados na unidade de terapia intensiva neonatal, a presença de cateter intravascular e a utilização de nutrição parenteral foram achados significativos. Não houve diferença significante quanto a resistência a oxacilina e produção de SLIME entre os ECN isolados das bacteremias verdadeiras e contaminantes. O critério clínico e a positividade da hemocultura até 48 horas após a incubação, utilizados em nossa definição, foram úteis para caracterizar as bacteremias verdadeiras por ECN.Coagulase-negative staphylococci (CNS are an important cause of nosocomial bacteremia and they are frequently considered as contaminants of blood-cultures. From October 1990 to September 1992, 300 positive blood-cultures for CNS at the Hospital São Paulo were studied and 141 CNS bacteremias were characterized as nosocomial bacteremias. Clinical and microbiological criteria were defined to differentiate between true CNS bacteremia and contaminated cultures. Only 20.6% of the CNS nosocomial bacteremia were considered as true bacteremia. Most of the CNS true nosocomial bacteremia were detected among newborns admitted to the neonatal intensive care unit; the presence of intravascular catheter and parenteral nutrition were significant findings. We did not detect significant difference between true nosocomial bacteremia and

  9. Misinterpretation of Gram Stain from the Stationary Growth Phase of Positive Blood Cultures forBrucellaandAcinetobacterSpecies.

    Science.gov (United States)

    Bazzi, Ali M; Al-Tawfiq, Jaffar A; Rabaan, Ali A

    2017-01-01

    Acinetobacter baumannii and Brucella species are Gram-negative organisms that are vulnerable to misinterpretation as Gram-positive or Gram-variable in blood cultures. We assess the random errors in gram stain interpretation to reduce the likelihood of such errors and therefore patient harm. Aerobic and anaerobic blood cultures from two patients in an acute care facility in Saudi Arabia were subjected to preliminary Gram-staining. In case 1, VITEK-2 Anaerobe Identification, repeat Gram staining from a blood agar plate, Remel BactiDrop™ Oxidase test, Urea Agar urease test and real-time PCR were used to confirm presence of Brucella and absence of Coryneform species. In case 2, repeat Gram- staining from the plate and the vials, VITEK-2 Gram-Negative Identification, real-time PCR and subculture on to Columbia agar, blood agar, and MacConkey agar were carried out to identify A. baumannii . In case 1, initially pleomorphic Gram-positive bacteria were identified. Coryneform species were suspected. Tiny growth was observed after 24 h on blood agar plates, and good growth by 48 h. Presence of Brucella species was ultimately confirmed. In case 2, preliminary Gram-stain results suggested giant Gram-positive oval cocci. Further testing over 18-24 h identified A. baumannii . Oxidase test from the plate and urease test from the culture vial is recommended after apparent identification of pleomorphic Gram-positive bacilli from blood culture, once tiny growth is observed, to distinguish Brucella from Corynebacterium species. If giant Gram-positive oval cocci are indicated by preliminary Gram-staining, it is recommended that the Gram stain be repeated from the plate after 4-6 h, or culture should be tested in Triple Sugar Iron (TSI) medium and the Gram stain repeated after 2-4 h incubation.

  10. Prophylactic antibiotics for preventing early central venous catheter Gram positive infections in oncology patients

    NARCIS (Netherlands)

    van de Wetering, M. D.; van Woensel, J. B. M.

    2003-01-01

    BACKGROUND: Long-term tunnelled central venous catheters (TCVC) are increasingly used in oncology patients. Despite guidelines on insertion, maintenance and use, infections remain an important complication. Most infections are caused by Gram-positive bacteria. Therefore antimicrobial prevention

  11. One Small Step for the Gram Stain, One Giant Leap for Clinical Microbiology.

    Science.gov (United States)

    Thomson, Richard B

    2016-06-01

    The Gram stain is one of the most commonly performed tests in the clinical microbiology laboratory, yet it is poorly controlled and lacks standardization. It was once the best rapid test in microbiology, but it is no longer trusted by many clinicians. The publication by Samuel et al. (J. Clin. Microbiol. 54:1442-1447, 2016, http://dx.doi.org/10.1128/JCM.03066-15) is a start for those who want to evaluate and improve Gram stain performance. In an age of emerging rapid molecular results, is the Gram stain still relevant? How should clinical microbiologists respond to the call to reduce Gram stain error rates? Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  12. Evaluation of gram stain as an alternative in the assessment of human spermatozoa quality.

    Science.gov (United States)

    Mantas, D; Msaouel, P; Angelopoulou, R

    2006-01-01

    During spermiogenesis, protaminosis and sperm chromatin condensation are important prerequisites for the preservation of DNA integrity in spermatozoa. The aim of this study is to assess Gram stain as an alternative technique for the evaluation of human sperm chromatin condensation status. Aniline blue and Gram staining were applied to semen samples from 34 donors in order to determine the relationship between sperm chromatin condensation and infertility. In addition, the possible correlation between morphology and vitality (eosin-Y staining) of spermatozoa compared with their nuclear status (aniline blue and Gram staining) was studied. Chromatin condensation and sperm vitality were significantly higher in fertile men compared to the subfertile. A significant correlation was found between chromatin condensation and (a) sperm vitality (p Gram staining may be used as a routine method in assisted reproduction laboratories and could assist in the evaluation of sperm quality as well as in the selection of the appropriate fertilization technique.

  13. Rose Bengal-decorated silica nanoparticles as photosensitizers for inactivation of gram-positive bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Guo Yanyan; Zhang Peng [Department of Chemistry, New Mexico Tech, Socorro, NM 87801 (United States); Rogelj, Snezna, E-mail: pzhang@nmt.edu [Department of Biology, New Mexico Tech, Socorro, NM 87801 (United States)

    2010-02-10

    A new type of photosensitizer, made from Rose Bengal (RB)-decorated silica (SiO{sub 2}-NH{sub 2}-RB) nanoparticles, was developed to inactivate gram-positive bacteria, including Methicillin-resistant Staphylococcus aureus (MRSA), with high efficiency through photodynamic action. The nanoparticles were characterized microscopically and spectroscopically to confirm their structures. The characterization of singlet oxygen generated by RB, both free and immobilized on a nanoparticle surface, was performed in the presence of anthracene-9,10-dipropionic acid. The capability of SiO{sub 2}-NH{sub 2}-RB nanoparticles to inactivate bacteria was tested in vitro on both gram-positive and gram-negative bacteria. The results showed that RB-decorated silica nanoparticles can inactivate MRSA and Staphylococcus epidermidis (both gram-positive) very effectively (up to eight-orders-of-magnitude reduction). Photosensitizers of such design should have good potential as antibacterial agents through a photodynamic mechanism.

  14. Cardiolipin, a major phospholipid of gram-positive bacteria that is not readily extractable

    NARCIS (Netherlands)

    Filgueiras, M.H.; Kamp, J.A.F. op den

    1980-01-01

    Extraction of phospholipids from stationary phase grown cells of the Gram+ bacteria, Bacillus megaterium, Bacillus subtilis, Bacillus cereus and Micrococcus lysodeikticus was found to be incomplete with various commonly used extraction procedures. Phosphatidylglycerol and phosphatidyl-ethanolamine

  15. Efficacy of telavancin, a lipoglycopeptide antibiotic, in experimental models of Gram-positive infection.

    Science.gov (United States)

    Hegde, Sharath S; Janc, James W

    2014-12-01

    Telavancin is a parenteral lipoglycopeptide antibiotic with a dual mechanism of action contributing to bactericidal activity against multidrug-resistant Gram-positive pathogens. It has been approved for the treatment of complicated skin and skin structure infections due to susceptible Gram-positive bacteria and hospital-acquired/ventilator-associated bacterial pneumonia due to Staphylococcus aureus when other alternatives are unsuitable. Telavancin has been demonstrated to be efficacious in multiple animal models of soft tissue, cardiac, systemic, lung, bone, brain and device-associated infections involving clinically relevant Gram-positive pathogens, including methicillin-resistant S. aureus, glycopeptide-intermediate S. aureus, heterogeneous vancomycin-intermediate S. aureus and daptomycin non-susceptible methicillin-resistant S. aureus. The AUC0-24h/MIC ratio is the primary pharmacodynamically-linked pharmacokinetic parameter. The preclinical data for telavancin supports further investigative clinical evaluation of its efficacy in additional serious infections caused by susceptible Gram-positive pathogens.

  16. First detection of bla TEM, SHV and CTX-M among Gram negative ...

    African Journals Online (AJOL)

    First detection of bla TEM, SHV and CTX-M among Gram negative bacilli exhibiting extended spectrum β- lactamase phenotype isolated at University Hospital Center, Yalgado Ouedraogo, Ouagadougou, Burkina Faso.

  17. Mars Global Reference Atmospheric Model (Mars-GRAM) Version 3.8: Users Guide

    Science.gov (United States)

    Justus, C. G.; James, B. F.

    1999-01-01

    Mars Global Reference Atmospheric Model (Mars-GRAM) Version 3.8 is presented and its new features are discussed. Mars-GRAM uses new values of planetary reference ellipsoid radii, gravity term, and rotation rate (consistent with current JPL values) and includes centrifugal effects on gravity. The model now uses NASA Ames Global Circulation Model low resolution topography. Curvature corrections are applied to winds and limits based on speed of sound are applied. Altitude of the F1 ionization peak and density scale height, including effects of change of molecular weight with altitude are computed. A check is performed to disallow temperatures below CO2 sublimination. This memorandum includes instructions on obtaining Mars-GRAM source code and data files and running the program. Sample input and output are provided. An example of incorporating Mars-GRAM as an atmospheric subroutine in a trajectory code is also given.

  18. Breeding high yielding varieties of pigeon pea, mungbean and black gram using induced mutations

    International Nuclear Information System (INIS)

    Pawar, S.E.; Wanjari, K.B.

    1994-01-01

    The present communication emphasis the developing of high yielding varieties of pigeon pea, mungbean and black gram using induced mutation with disease resistance in these crops. This would help in stabilisation of the higher yield potential

  19. Gram-negative rod bacteremia after cardiovascular surgery: Clinical features and prognostic factors

    Directory of Open Access Journals (Sweden)

    Sayaka Tago

    2017-06-01

    Conclusion: Graft replacement was the most common surgical procedure in patients with GNRB after CVS. Empirical antibiotics covering Gram-negative rods including P. aeruginosa should be considered if bacteremia is suspected in unstable patients after CVS.

  20. Tachypleus lysate test for endotoxin in patients with Gram negative bacterial infections.

    Science.gov (United States)

    Usawattanakul, W; Tharavanij, S; Limsuwan, A

    1979-03-01

    Amoebocyte lysate from the horseshoe crabs (Tachypleus gigas) which abounds in the Gulf of Thailand was used to detect endotoxin in patients with Gram-negative bacteremia, in patients with Gram-positive bacterial infections as well as in the control. The Tachypleus lysate test (TLT) was positive in 94.4% of 36 patients with Gram-negative bacteremia before initiation of antibiotic therapy. Only 4% of 50 healthy individuals were positive and all 7 patients with Gram-positive bacterial infections were negative. The threshold sensitivity of TLT was 0.625 micrograms endotoxin per ml of the plasma. In comparison with the commercial Limulus lysate test (LLT), the TLT was slightly more sensitive in exhibiting higher grade of reaction, eventhough the threshold sensitivity was the same.

  1. EFFECTS OF THE GRAM STAIN ON MICROSPHERES FROM THERMAL POLYAMINO ACIDS1

    Science.gov (United States)

    Fox, Sidney W.; Yuyama, Shuhei

    1963-01-01

    Fox, Sidney W. (The Florida State University, Tallahassee) and Shuhei Yuyama. Effects of the Gram stain on microspheres from thermal polyamino acids. J. Bacteriol. 85:279–283. 1963.—Microspheres produced from acid proteinoid accept the Gram stain. The stain is negative, but microspheres produced from mixtures containing a sufficient proportion of lysine proteinoid stain positive. Microspheres produced from mixtures containing the appropriate proportions contain individuals which stain positive and others which stain negative. Images PMID:13959050

  2. A Flow-Cytometric Gram-Staining Technique for Milk-Associated Bacteria

    Science.gov (United States)

    Holm, Claus; Jespersen, Lene

    2003-01-01

    A Gram-staining technique combining staining with two fluorescent stains, Oregon Green-conjugated wheat germ agglutinin (WGA) and hexidium iodide (HI) followed by flow-cytometric detection is described. WGA stains gram-positive bacteria while HI binds to the DNA of all bacteria after permeabilization by EDTA and incubation at 50°C for 15 min. For WGA to bind to gram-positive bacteria, a 3 M potassium chloride solution was found to give the highest fluorescence intensity. A total of 12 strains representing some of the predominant bacterial species in bulk tank milk and mixtures of these were stained and analyzed by flow cytometry. Overall, the staining method showed a clear differentiation between gram-positive and gram-negative bacterial populations. For stationary-stage cultures of seven gram-positive bacteria and five gram-negative bacteria, an average of 99% of the cells were correctly interpreted. The method was only slightly influenced by the growth phase of the bacteria or conditions such as freezing at −18°C for 24 h. For any of these conditions, an average of at least 95% of the cells were correctly interpreted. When stationary-stage cultures were stored at 5°C for 14 days, an average of 86% of the cells were correctly interpreted. The Gram-staining technique was applied to the flow cytometry analysis of bulk tank milk inoculated with Staphylococcus aureus and Escherichia coli. These results demonstrate that the technique is suitable for analyzing milk samples without precultivation. PMID:12732558

  3. Accuracy of tracheal aspirate gram stain in predicting Staphylococcus aureus infection in ventilator-associated pneumonia.

    Science.gov (United States)

    Seligman, Renato; Seligman, Beatriz Graeff Santos; Konkewicz, Loriane; Dos Santos, Rodrigo Pires

    2015-01-01

    The Gram stain can be used to direct initial empiric antimicrobial therapy when complete culture is not available. This rapid test could prevent the initiation of inappropriate therapy and adverse outcomes. However, several studies have attempted to determine the value of the Gram stain in the diagnosis and therapy of bacterial infection in different populations of patients with ventilator-associated pneumonia (VAP) with conflicting results. The objective of this study is to evaluate the accuracy of the Gram stain in predicting the existence of Staphylococcus aureus infections from cultures of patients suspected of having VAP. This prospective single-center open cohort study enrolled 399 patients from December 2005 to December 2010. Patients suspected of having VAP by ATS IDSA criteria were included. Respiratory secretion samples were collected by tracheal aspirate (TA) for standard bacterioscopic analysis by Gram stain and culture. Respiratory secretion samples collected by tracheal aspirates of 392 patients were analyzed by Gram stain and culture. When Gram-positive cocci were arranged in clusters, the sensitivity was 68.4%, specificity 97.8%, positive predictive value 88.1% and negative predictive value 92.8% for predicting the presence of Staphylococcus aureus in culture (p Gram stain can be used to rule out the presence of Staphylococcus aureus in patients with a clinical diagnosis of VAP with a 92.8% Negative Predictive Value. Therefore, 7.2% of patients with Staphylococcus aureus would not be protected by an empiric treatment that limits antimicrobial coverage to Staphylococcus aureus only when Gram positive cocci in clusters are identified.

  4. Utility of Gram stain for the microbiological analysis of burn wound surfaces.

    Science.gov (United States)

    Elsayed, Sameer; Gregson, Daniel B; Lloyd, Tracie; Crichton, Marilyn; Church, Deirdre L

    2003-11-01

    Surface swab cultures have attracted attention as a potential alternative to biopsy histology or quantitative culture methods for microbiological burn wound monitoring. To our knowledge, the utility of adding a Gram-stained slide in this context has not been evaluated previously. To determine the degree of correlation of Gram stain with culture for the microbiological analysis of burn wound surfaces. Prospective laboratory analysis. Urban health region/centralized diagnostic microbiology laboratory. Burn patients hospitalized in any Calgary Health Region burn center from November 2000 to September 2001. Gram stain plus culture of burn wound surface swab specimens obtained during routine dressing changes or based on clinical signs of infection. Degree of correlation (complete, high, partial, none), including weighted kappa statistic (kappa(w)), of Gram stain with culture based on quantitative microscopy and degree of culture growth. A total of 375 specimens from 50 burn patients were evaluated. Of these, 239 were negative by culture and Gram stain, 7 were positive by Gram stain only, 89 were positive by culture only, and 40 were positive by both methods. The degree of complete, high, partial, and no correlation of Gram stain with culture was 70.9% (266/375), 1.1% (4/375), 2.4% (9/375), and 25.6% (96/375), respectively. The degree of correlation for all 375 specimens, as expressed by the weighted kappa statistic, was found to be fair (kappa(w) = 0.32).Conclusion.-The Gram stain is not suitable for the microbiological analysis of burn wound surfaces.

  5. Colistin: an Antibiotic and Its Role in Multiresistant Gram-negative Infections

    Directory of Open Access Journals (Sweden)

    Tonny Loho

    2016-05-01

    Full Text Available Increasing number of infection cases caused by multiresistant Gram-negative bacteria or multidrug resistant organism (MDRO has become a major problem worldwide since there have been a lot of resistance to many classes of antibiotics. Mutant isolates such as fluoroquinolone-resistant and β-lactamase-resistant bacteria have been commonly found, particularly in intensive care unit (ICU. During the last two decades, there has been no study of developing antibiotics in search of discovering new type of antibiotics; meanwhile, the resistance of Gram-negative bacteria or MDRO to antibiotics is increasing. Colistin or polymyxin E is an old antibiotic, which has been used since 1959 for treating infection caused by Gram-negative MDRO. It was revealed that colistin has side effects of nephrotoxicity and neurotoxicity; therefore, the use of this antibiotic was stopped and it was replaced by other antibiotics which were effective and were considered safer at that time. There is an increasing number of infections with multi-resistant Gram-negative (MDRO against the available antibiotics and the availability of alternative antibiotics has not been satisfying; therefore, microbiologists are searching back to the old option, which has been proven to be effective against multi-resistant Gram-negative bacteria, the old antibiotic that has been long forgotten, i.e. colistin, as an alternative treatment against Gram-negative MDRO. It is expected that colistin may have essential and reliable role as future antibiotics for treatment of multi-resistant Gram-negative infections and as an alternative of antibiotics that have been available so far. Key words: antibiotics, colistin, Gram-negative, multidrug resistant organism (MDRO.

  6. Gram-Positive Uropathogens, Polymicrobial Urinary Tract Infection, and the Emerging Microbiota of the Urinary Tract.

    Science.gov (United States)

    Kline, Kimberly A; Lewis, Amanda L

    2016-04-01

    Gram-positive bacteria are a common cause of urinary-tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI.

  7. Gram-Positive Uropathogens, Polymicrobial Urinary Tract Infection, and the Emerging Microbiota of the Urinary Tract

    Science.gov (United States)

    Kline, Kimberly A.; Lewis, Amanda L.

    2015-01-01

    Gram-positive bacteria are a common cause of urinary tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI. PMID:27227294

  8. Evaluation of Commercial-off-the-Shelf Materials for the Preservation of Gram Positive Vegetative Cells

    Science.gov (United States)

    2017-02-01

    EVALUATION OF COMMERCIAL-OFF-THE-SHELF MATERIALS FOR THE PRESERVATION OF GRAM-POSITIVE VEGETATIVE CELLS ECBC-TR-1435 Daniel Angelini...Commercial-off-the-Shelf Materials for the Preservation of Gram-Positive Vegetative Cells 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...through direct culture of the agents themselves. Materials have been developed to preserve the viability of pathogens contained within clinical

  9. The NASA/MSFC Global Reference Atmospheric Model-1995 version (GRAM-95)

    Science.gov (United States)

    Justus, C. G.; Jeffries, W. R., III; Yung, S. P.; Johnson, D. L.

    1995-01-01

    The latest version of the Global Reference Atmospheric Model (GRAM-95) is presented and discussed. GRAM-95 uses the new Global Upper Air Climatic Atlas (GUACA) CD-ROM data set, for 0- to 27-km altitudes. As with earlier versions, GRAM-95 provides complete geographical and altitude coverage for each month of the year. Individual years 1985 to 1991 and a period-of-record (1980 to 1991) can be simulated for the GUACA height range. GRAM-95 uses a specially developed data set, based on Middle Atmosphere Program (MAP) data, for the 20- to 120-km height range, and the NASA Marshall Engineering Thermosphere (MET) model for heights above 90 km. Fairing techniques assure a smooth transition in the overlap height ranges (20 to 27 km and 90 to 120 km). In addition to the traditional GRAM variables of pressure, density, temperature and wind components, GRAM-95 now includes water vapor and 11 other atmospheric constituents (O3, N2O, CO, CH4, CO2, N2, O2, O, A, He, and H). A new, variable-scale perturbation model provides both large-scale and small-scale deviations from mean values for the thermodynamic variables and horizontal and vertical wind components. The perturbation model includes new features that simulate intermittency (patchiness) in turbulence and small-scale perturbation fields. The density perturbations and density gradients (density shears) computed by the new model compare favorably in their statistical characteristics with observed density perturbations and density shears from 32 space shuttle reentry profiles. GRAM-95 provides considerable improvement in wind estimates from the new GUACA data set, compared to winds calculated from the geostrophic wind relations previously used in the 0- to 25-km height range. The GRAM-95 code has been put into a more modular form, easier to incorporate as subroutines in other programs (e.g., trajectory codes). A complete user's guide for running the program, plus sample input and output, is provided.

  10. Exact closed-form expression for the inverse moments of one-sided correlated Gram matrices

    KAUST Repository

    Elkhalil, Khalil

    2016-08-15

    In this paper, we derive a closed-form expression for the inverse moments of one sided-correlated random Gram matrices. Such a question is mainly motivated by applications in signal processing and wireless communications for which evaluating this quantity is a question of major interest. This is for instance the case of the best linear unbiased estimator, in which the average estimation error corresponds to the first inverse moment of a random Gram matrix.

  11. Mars-GRAM: Increasing the Precision of Sensitivity Studies at Large Optical Depths

    Science.gov (United States)

    Justh, Hilary L.; Justus, C. G.; Badger, Andrew M.

    2010-01-01

    The Mars Global Reference Atmospheric Model (Mars-GRAM) is an engineering-level atmospheric model widely used for diverse mission applications. Mars-GRAM's perturbation modeling capability is commonly used, in a Monte-Carlo mode, to perform high fidelity engineering end-to-end simulations for entry, descent, and landing (EDL). It has been discovered during the Mars Science Laboratory (MSL) site selection process that Mars-GRAM, when used for sensitivity studies for MapYear=0 and large optical depth values such as tau=3, is less than realistic. A comparison study between Mars atmospheric density estimates from Mars-GRAM and measurements by Mars Global Surveyor (MGS) has been undertaken for locations of varying latitudes, Ls, and LTST on Mars. The preliminary results from this study have validated the Thermal Emission Spectrometer (TES) limb data. From the surface to 80 km altitude, Mars-GRAM is based on the NASA Ames Mars General Circulation Model (MGCM). MGCM results that were used for Mars-GRAM with MapYear=0 were from a MGCM run with a fixed value of tau=3 for the entire year at all locations. This has resulted in an imprecise atmospheric density at all altitudes. To solve this pressure-density problem, density factor values were determined for tau=.3, 1 and 3 that will adjust the input values of MGCM MapYear 0 pressure and density to achieve a better match of Mars-GRAM MapYear 0 with TES observations for MapYears 1 and 2 at comparable dust loading. The addition of these density factors to Mars-GRAM will improve the results of the sensitivity studies done for large optical depths.

  12. Functional synergy of α-helical antimicrobial peptides and traditional antibiotics against Gram-negative and Gram-positive bacteria in vitro and in vivo.

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    Feng, Q; Huang, Y; Chen, M; Li, G; Chen, Y

    2015-01-01

    In this study, the antimicrobial activities based on the synergistic effects of traditional antibiotics (imipenem, cefepime, levofloxacin hydrochloride and vancomycin) and antimicrobial peptides (AMPs; PL-5, PL-31, PL-32, PL-18, PL-29 and PL-26), alone or in combination, against three Gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae and Staphylococcus epidermidis) and three Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae) were investigated. In addition, the antimicrobial activity that was based on the synergistic effects of levofloxacin hydrochloride and PL-5 against Staphylococcus aureus in vivo was explored in a mouse infection model. Traditional antibiotics and AMPs showed significant synergistic effects on the antibacterial activities against the different Gram-positive and Gram-negative bacteria in vitro. A strong synergistic effect in the PL-5 and levofloxacin hydrochloride combination against Staphylococcus aureus was observed in the mouse infection model in vivo. The mechanism of synergistic action was due to the different targets of AMPs and traditional antibiotics. The combination of AMPs and traditional antibiotics can dramatically enhance antimicrobial activity and may help prevent or delay the emergence of antibiotic resistance. Thus, this combination therapy could be a promising approach to treat bacterial infections, particularly mixed infections and multi-antibiotic-resistant infections, in the clinics.

  13. Comparison of killing of gram-negative and gram-positive bacteria by pure singlet oxygen. [Salmonella typhimurium; Escherichia coli; Sarcina lutea; Staphylococcus aureus; Streptococcus lactis; Streptococcus faecalis

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    Dahl, T.A.; Midden, W.R. (Bowling Green State Univ., OH (USA)); Hartman, P.E. (Johns Hopkins Univ., Baltimore, MD (USA))

    1989-04-01

    Gram-negative and gram-positive bacteria were found to display different sensitivities to pure singlet oxygen generated outside of cells. Killing curves for Salmonella typhimurium and Escherichia coli strains were indicative of multihit killing, whereas curves for Sarcina lutea, Staphylococcus aureus, Streptococcus lactis, and Streptococcus faecalis exhibited single-hit kinetics. The S. typhimurium deep rough strain TA1975, which lacks nearly all of the cell wall lipopolysaccharide coat and manifests concomitant enhancement of penetration by some exogenous substances, responded to singlet oxygen with initially faster inactivation than did the S. typhimurium wild-type strain, although the maximum rates of killing appeared to be quite similar. The structure of the cell wall thus plays an important role in susceptibility to singlet oxygen. The outer membrane-lipopolysaccharide portion of the gram-negative cell wall initially protects the bacteria from extracellular singlet oxygen, although it may also serve as a source for secondary reaction products which accentuate the rates of cell killing. S. typhimurium and E. coli strains lacking the cellular antioxidant, glutathione, showed no difference from strains containing glutathione in response to the toxic effects of singlet oxygen. Strains of Sarcina lutea and Staphylococcus aureus that contained carotenoids, however, were far more resistant to singlet oxygen lethality than were both carotenoidless mutants of the same species and other gram-positive species lacking high levels of protective carotenoids.

  14. Sistema de tareas para la enseñanza combinada de la gramática comunicativa y la gramática tradicional de lengua inglesa

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    Nancy del Carmen Jiménez Figueredo

    2015-03-01

    Full Text Available Se realizó el diseño de un sistema de tareas para la enseñanza combinada de la gramática comunicativa y la gramática tradicional de lengua inglesa, con metodología cuali-cuantitativa, en la Facultad de Ciencias Médicas “Zoilo Marinello Vidaurreta” de la Universidad de Ciencias Médicas de Las Tunas, durante el período comprendido entre septiembre de 2011 y julio de 2014. El objetivo estuvo direccionado a perfeccionar la corrección lingüística en el proceso de enseñanza-aprendizaje del idioma Inglés. La realización del diseño contó con: una revisión bibliográfica de los principales enfoques utilizados en la enseñanza-aprendizaje del Inglés; la revisión documental, que permitió determinar las insuficiencias lingüísticas y la necesidad de combinar la gramática comunicativa con la gramática tradicional, en los estudiantes del cuarto año de la carrera de Estomatología; el intercambio con profesionales con más de quince años de experiencia, para obtener información acerca del proceso de enseñanza-aprendizaje de la gramática; y la aplicación de una valoración equivalente al juicio de expertos, método de agregados individuales, para valorar la propuesta. Los principales resultados fueron: la caracterización de las insuficiencias provocadas por la absolutización del enfoque comunicativo en la enseñanza de la gramática de la lengua inglesa y el diseño de un sistema de tareas para el proceso de enseñanza-aprendizaje de la gramática inglesa en estos estudiantes

  15. Outcomes of transurethral resection of the prostate in benign prostatic hyperplasia comparing prostate size of more than 80 grams to prostate size less than 80 grams.

    Science.gov (United States)

    Joshi, H N; De Jong, I J; Karmacharya, R M; Shrestha, B; Shrestha, R

    2014-01-01

    Benign prostatic hyperplasia is a condition occurring in elderly men in which the prostate gland is enlarged, hence the condition also known as benign enlargement of prostate. Benign hyperplasia can lead to both obstructive and irritative symptoms. Transurethral resection of prostate (TURP) still remains the gold standard modality of surgical treatment of obstructive lower urinary tract symptoms due to Benign hyperplasia. The objective of this study was to evaluate the outcomes of TURP in large prostate (>80 grams) in comparison to small prostate (grams) in terms of efficacy, safety and complications. A total of 65 cases included in this prospective study, which were operated by a single surgeon with conventional monopolar TURP using standard technique. Intra -operative and post-operative complications, pre and post- operative quality of life (QoL) and international prostate symptom score (IPSS), operative time, time to removal of catheter and hospital stay were evaluated between small and large prostate gland volumes. Out of 65 cases, 30 were with large prostate size i.e. 80 grams or more (group 1), and 35 cases were with small prostate size than 80 grams size (group 2). Mean age was 71.8 SD ± 6.9 years in group 1 and 68.2 SD ± 12.7 years in group 2. The mean preoperative volume of prostate was 88.8 grams (range 80-115 grams) in group 1 and 40.3 (range 20-65 grams) in group 2. The mean preoperative post void residual volume of urine (PVRU) was 244 ml SD ± 190.8 ml in group 1 and 117 ml ± 70.3 ml in group 2. Mean resection time in group 1 was 110 (range 90-130) minutes and in group 2 it was 90 minutes (range 55-115) minutes. There were quite satisfactory improvements in IPSS and QoL. No significant complications were observed except TUR syndrome in 2 cases from group 2, which were managed well in postoperative period. With meticulous resection and intra-operative haemostasis using continuous out flow resectoscope, conventional monopolar TURP is equally safe and

  16. The importance of Gram positive bacteria as the cause of canine pyometra

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    Marcos Cezar Sant' anna

    2017-05-01

    Full Text Available E. coli is the main bacteria isolated from infected uterus and bacterial endotoxin can lead to fatal endotoxic shock. Systemic inflammatory response syndrome (SIRS precedes the endotoxic shock. Thus, early recognition of SIRS is important for patient treatment and prognostic. In Brazil, Gram positive bacteria are responsible for approximately 20% of all pyometra cases, and there is limited information about pathophysiology of shock and tissue injury. The aim of this study was to investigate the capacity of Gram positive bacteria to cause SIRS in bitches with pyometra. A prospective follow-up of 67 bitches with pyometra was performed, which were classified as SIRS + and SIRS- on admission. All bitches were surgically treated (ovariohysterectomy, uterine contents were collected in a sterile manner and the material was submitted to microbiological evaluation. Were identified in 55.2% of bitches E. coli (G1, 23.9% other Gram negative bacteria (G2 and 20.9% Gram positive bacteria (G3. The leukocyte profile, serum biochemistry and prevalence of SIRS were similar between the groups. It is concluded that Gram positive bacteria have the capacity to promote tissue damage and can lead the patient to death after SIRS and shock, as well as by E. coli and other Gram negative.

  17. [Comparison of the quick Gram stain method to the B&M modified and favor methods].

    Science.gov (United States)

    Osawa, Kayo; Kataoka, Nobumasa; Maruo, Toshio

    2011-01-01

    The Gram stain is an established method for bacterial identification, but the time needed to carry out this stain is 2-3 min. We attempted to shorten this time and stained a total of 70 clinical specimens isolated from using the Bartholomew & Mittwer (B&M) modified or Favor methods with a 3 s duration for washing and staining steps. Results were plotted and analyzed using a Hue Saturation Intensity (HSI) model. The range based on a plot of the two methods with the HSI model was presented as a reference interval. Our results indicated that 100% (35/35) of strains were Gram positive and 97.1% (34/35) were Gram negative for the quick B&M modified method. In the quick Favor method, 80.0% (28/35) were Gram positive and 68.6% (24/35) of strains were Gram negative. We propose that the quick B&M modified method is equivalent to the standard Gram staining method and is superior to the quick Favor method.

  18. A 2-year study of Gram stain competency assessment in 40 clinical laboratories.

    Science.gov (United States)

    Goodyear, Nancy; Kim, Sara; Reeves, Mary; Astion, Michael L

    2006-01-01

    We used a computer-based competency assessment tool for Gram stain interpretation to assess the performance of 278 laboratory staff from 40 laboratories on 40 multiple-choice questions. We report test reliability, mean scores, median, item difficulty, discrimination, and analysis of the highest- and lowest-scoring questions. The questions were reliable (KR-20 coefficient, 0.80). Overall mean score was 88% (range, 63%-98%). When categorized by cell type, the means were host cells, 93%; other cells (eg, yeast), 92%; gram-positive, 90%; and gram-negative, 88%. When categorized by type of interpretation, the means were other (eg, underdecolorization), 92%; identify by structure (eg, bacterial morphologic features), 91%; and identify by name (eg, genus and species), 87%. Of the 6 highest-scoring questions (mean scores, > or = 99%) 5 were identify by structure and 1 was identify by name. Of the 6 lowest-scoring questions (mean scores, gram-negative and 1 was host cells. By type of interpretation, 2 were identify by structure and 4 were identify by name. Computer-based Gram stain competency assessment examinations are reliable. Our analysis helps laboratories identify areas for continuing education in Gram stain interpretation and will direct future revisions of the tests.

  19. Widespread Fosfomycin Resistance in Gram-Negative Bacteria Attributable to the Chromosomal fosA Gene

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    Ryota Ito

    2017-08-01

    Full Text Available Fosfomycin is a decades-old antibiotic which is being revisited because of its perceived activity against many extensively drug-resistant Gram-negative pathogens. FosA proteins are Mn2+ and K+-dependent glutathione S-transferases which confer fosfomycin resistance in Gram-negative bacteria by conjugation of glutathione to the antibiotic. Plasmid-borne fosA variants have been reported in fosfomycin-resistant Escherichia coli strains. However, the prevalence and distribution of fosA in other Gram-negative bacteria are not known. We systematically surveyed the presence of fosA in Gram-negative bacteria in over 18,000 published genomes from 18 Gram-negative species and investigated their contribution to fosfomycin resistance. We show that FosA homologues are present in the majority of genomes in some species (e.g., Klebsiella spp., Enterobacter spp., Serratia marcescens, and Pseudomonas aeruginosa, whereas they are largely absent in others (e.g., E. coli, Acinetobacter baumannii, and Burkholderia cepacia. FosA proteins in different bacterial pathogens are highly divergent, but key amino acid residues in the active site are conserved. Chromosomal fosA genes conferred high-level fosfomycin resistance when expressed in E. coli, and deletion of chromosomal fosA in S. marcescens eliminated fosfomycin resistance. Our results indicate that FosA is encoded by clinically relevant Gram-negative species and contributes to intrinsic fosfomycin resistance.

  20. Analysis of n-gram based promoter recognition methods and application to whole genome promoter prediction.

    Science.gov (United States)

    Rani, T Sobha; Bapi, Raju S

    2009-01-01

    Promoter prediction is an important and complex problem. Pattern recognition algorithms typically require features that could capture this complexity. A special bias towards certain combinations of base pairs in the promoter sequences may be possible. In order to determine these biases n-grams are usually extracted and analyzed. An n-gram is a selection of n contiguous characters from a given character stream, DNA sequence segments in this case. Here a systematic study is made to discover the efficacy of n-grams for n = 2, 3, 4, 5 in promoter prediction. A study of n-grams as features for a neural network classifier for E. coli and Drosophila promoters is made. In case of E. coli n=3 and in case of Drosophila n=4 seem to give optimal prediction values. Using the 3-gram features, promoter prediction in the genome sequence of E. coli is done. The results are encouraging in positive identification of promoters in the genome compared to software packages such as BPROM, NNPP, and SAK. Whole genome promoter prediction in Drosophila genome was also performed but with 4-gram features.

  1. O discurso da norma na gramática de João de Barros

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    Diana Luz Pessoa de Barros

    2001-02-01

    Full Text Available

    O estudo sobre o discurso da norma na Gramática de João de Barros é parte de uma pesquisa em desenvolvimento acerca do discurso da norma em gramáticas da língua portuguesa, do século XVI à atualidade, no âmbito do projeto coletivo "História das idéias linguisticas no Brasil: ética e política das línguas". As gramáticas são analisadas como discursos, na perspectiva teórica e metodológica da semiótica discursiva francesa. São examinados, particularmente, três procedimentos discursivos: as modalizações dos sujeitos e dos objetos, que constituem três tipos de discursos da norma - a norma natural, predominante em João de Barros, a norma prescritiva e a norma usual - ; as projeções enunciativas de pessoa e de tempo na gramática em exame; as relações intertextuais entre o discurso da norma na gramática e os discursos gramaticais da época, com que João de Barros concorda, e também com o discurso colonialista português, o da Monarquia e o da Igreja, da época, discursos que sua gramática ajuda a construir, sobretudo pelos exemplos.

  2. Clinical update on linezolid in the treatment of Gram-positive bacterial infections

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    Ager S

    2012-06-01

    Full Text Available Sally Ager, Kate GouldDepartment of Microbiology, Newcastle upon Tyne Hospitals Trust, Freeman Hospital, High Heaton, Newcastle upon Tyne, UKAbstract: Gram-positive pathogens are a significant cause of morbidity and mortality in both community and health care settings. Glycopeptides have traditionally been the antibiotics of choice for multiresistant Gram-positive pathogens but there are problems with their use, including the emergence of glycopeptide-resistant strains, tissue penetration, and achieving and monitoring adequate serum levels. Newer antibiotics such as linezolid, a synthetic oxazolidinone, are available for the treatment of resistant Gram-positive bacteria. Linezolid is active against a wide range of Gram-positive bacteria and has been generally available for the treatment of Gram-positive infections since 2000. There are potential problems with linezolid use, including its bacteriostatic action and the relatively high incidence of reported adverse effects, particularly with long-term use. Long-term use may also be complicated by the development of resistance. However, linezolid has been shown to be clinically useful in the treatment of several serious infections where traditionally bacteriocidal agents have been required and many of its adverse effects are reversible on cessation. It has also been shown to be a cost-effective treatment option in several studies, with its high oral bioavailability allowing an early change from intravenous to oral formulations with consequent earlier patient discharge and lower inpatient costs.Keywords: linezolid, oxazolidinone, multi-resistant, gram-positive, MRSA, VRE, cost-benefit

  3. Acute kidney injury in ELBW infants (grams) and its associated risk factors.

    Science.gov (United States)

    Arcinue, R; Kantak, A; Elkhwad, M

    2015-01-01

    The advancement of neonatology over the past 20 years has allowed a greater number of ELBW infants to survive. However, these advancements have contributed to the increased incidence of acute kidney injury (AKI) seen in this population. Understanding the risk factors for AKI in this population of ELBW infants is imperative for the successful survival of these infants since the morbidity and mortality rates from this disease are increasing. 1) to determine the prevalence of AKI in ELBW (grams). 2) to compare the mortality rate of ELBW infants (grams) with and without AKI; and 3) to identify the associated risk factors of AKI in ELBW infants (grams). A retrospective chart review of all infants with AKI as defined by AKIN criterias, admitted to the NICU between 1998 and 2008 was conducted. Case-controls were matched for BW, gestational age and date of birth, (SPSS v17.0 software, using Student's t test, X2 test, and Mann-Whitney U test were used for statistical analysis. The prevalence rate of ELBW infants (grams) with AKI admitted at CHMCA NICU from 1998 to 2008 was 26% . The mortality rate of ELBW infants (grams) with AKI was 54% , compared to 20% in those ELBW infants who did not have AKI. The associated risk factors of AKI in the ELBW infants (grams) were as follows: presence of maternal placental abruption/bleeding, grade III or IV IVH, PDA, positive culture/s, NEC, use of steroid, nephrotoxic drugs, and longer use of the ventilator and TPN.

  4. Atividade antimicrobiana in vitro de quinupristina/dalfopristina para cocos gram-positivos isolados de cinco centros brasileiros: resultado do estudo de vigilância L-SMART Antimicrobial in vitro activity of quinupristin/dalfopristin against gram-positive cocci isolated from 5 Brazilian centers: results from the local smart (L-SMART surveillance study

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    Caio Mendes

    2002-07-01

    Full Text Available Há alguns anos tem-se verificado um aumento progressivo da resistência de alguns cocos gram-positivos a determinados antimicrobianos. Este aumento da resistência tem sido observado principalmente no ambiente hospitalar, e as bactérias mais comumente envolvidas são os Staphylococcus spp. e os Enterococcus spp. Devido a este fato, novos antimicrobianos são avaliados para o tratamento de infecções causadas por estas cepas multirresistentes. A associação quinupristina/dalfopristina (Q/D, também conhecida como Synercid®, é um antibacteriano da classe das estreptograminas, de uso endovenoso, composto por dois derivados semi-sintéticos da pristinamicina. A combinação das estreptograminas B e A na razão de 30:70 tem atividade antimicrobiana voltada para cocos gram--positivos, como Staphylococcus spp., Streptococcus spp., incluindo S. pneumoniae e Enterococcus faecium, sendo o E. faecalis habitualmente resistente. Neste estudo foi avaliada a atividade in vitro de Q/D e outros oito antimicrobianos frente a 631 amostras de cocos gram-positivos isoladas de cinco centros brasileiros, complementadas com outras 20 cepas de E. faecium resistentes à vancomicina, provenientes dos Estados Unidos. Para a avaliação da sensibilidade aos antimicrobianos foi determinada a concentração inibitória mínima (MIC pelo método do Etest (AB Biodisk, Solna, Suécia e as cepas testadas foram: Staphylococcus aureus (n = 267, Staphylococcus coagulase negativo (n = 131, Streptococcus pneumoniae (n = 130, Streptococcus beta-hemolíticos (n = 28, Enterococcus faecalis (n = 44 e E. faecium (n = 51. A Q/D demonstrou excelente atividade contra Staphylococcus spp., independente de serem sensíveis ou resistentes à oxacilina. Para S. pneumoniae, a Q/D apresentou igualmente uma ótima atividade, inclusive para as cepas com resistência intermediária ou total para penicilina. Entre as cepas de E. faecium sensíveis à vancomicina, o MIC90 de Q/D obtido foi de 3µg

  5. Sensitivity of Gram stain in the diagnosis of urethritis in men.

    Science.gov (United States)

    Orellana, M Angeles; Gómez-Lus, M Luisa; Lora, David

    2012-06-01

    Acute urethritis is among the most common types of sexually transmitted diseases in men. The diagnosis usually requires microscopic evidence of urethritis, but sometimes urethral pathogens are detected in asymptomatic men without such evidence. The aims of this study were to assess the sensitivity of Gram stain in men with urethral symptoms and to relate it to the microorganisms isolated. Between January 2006 and December 2007, 491 urethral samples were analysed. The authors assessed the presence of leukocytes by Gram stain and tested specifically for Chlamydia trachomatis, Ureaplasma urealyticum, Mycoplasma hominis and Trichomonas vaginalis, as well as analysing the results of conventional culture. The percentages of positive samples as a function of Gram category were two or less polymorphonuclear leukocytes (PMNLs)/high-power field (HPF) 25% (92/364), three to four PMNLs/HPF 32% (18/57) and five or more PMNLs/HPF 54% (38/70). Classing samples with more than two PMNLs/HPF as positive, the sensitivity, specificity and positive likelihood ratio for Gram stain were 38% (95% CI 30 to 46), 79% (95% CI 75 to 84) and 1.8 (95% CI 1.4 to 2.4), respectively. On the other hand, taking as positive five or more PMNLs/HPF, the sensitivity, specificity and positive likelihood ratio for Gram stain were 26% (95% CI 18 to 33), 91% (95% CI 87 to 94) and 2.7 (95% CI 1.8 to 4.2), respectively. The sensitivity of Gram stain to Neisseria gonorrhoeae, Chlamydia trachomatis and Ureaplasma urealyticum were 80% (95% CI 64 to 96), 23% (95% CI 8 to 39) and 11% (95% CI 2 to 20), respectively. The low sensitivity of Gram stain means that negative results do not exclude the presence of urethritis in symptomatic patients.

  6. Tracheal aspirate Gram stain has limited sensitivity and specificity for detecting Staphylococcus aureus.

    Science.gov (United States)

    Tetenta, Sodienye; Metersky, Mark L

    2011-01-01

    The increasing incidence of respiratory infections due to methicillin resistant Staphylococcus aureus has resulted in increased empirical use of antibiotics active against this pathogen. There are limited data available as to whether the Gram stain of respiratory tract secretions accurately predicts growth of S. aureus. We theorized that the distinctive morphology of S. aureus would allow rapid, accurate identification of the organism in respiratory secretions. The authors reviewed all available Gram stains of tracheal aspirates sent to our hospital's microbiology laboratory between 1 April 2008 and 31 October 2008, while blinded to the culture result, and recorded the presence or absence of organisms with a morphology consistent with S. aureus. These results were correlated with the semiquantitative culture result. Among 136 tracheal aspirates studied, 50 (37%) grew S. aureus. The Gram stain was read as positive for organisms consistent with S. aureus in 34 of these. Among 86 samples that did not grow S. aureus, the Gram stain was read as negative in 62. Therefore, the Gram stain had a sensitivity of 68%, a specificity of 72%, a negative predictive value of 80% and a positive predictive value of 59% for culture of S. aureus. False negative Gram stains were more likely when the culture revealed only rare or small growth of S. aureus (P = 0.01). In this study, the tracheal aspirate Gram stain read by an experienced clinician who was not a microbiologist, was not accurate enough to reliably predict the growth of S. aureus. © 2010 The Authors. Respirology © 2010 Asian Pacific Society of Respirology.

  7. Gram and acridine orange staining for diagnosis of septic arthritis in different patient populations.

    Science.gov (United States)

    Cunningham, Gregory; Seghrouchni, Khalid; Ruffieux, Etienne; Vaudaux, Pierre; Gayet-Ageron, Angèle; Cherkaoui, Abdessalam; Godinho, Eduardo; Lew, Daniel; Hoffmeyer, Pierre; Uçkay, Ilker

    2014-06-01

    The sensitivity of Gram staining is known to be suboptimal for the diagnosis of native joint septic arthritis. We lack information about the accuracy of Gram compared to other microscopic staining techniques for predicting infection in different patient populations. This was a cohort study with cost evaluations at the Orthopaedic Service of Geneva University Hospitals (January 1996-October 2012). Among 500 episodes of arthritis (196 with immunosuppression, 227 with underlying arthroplasties and 69 with gout or other crystals in synovial fluid), Gram staining revealed pathogens in 146 episodes (146/500, 29 %) or in 146 of the 400 culture-positive episodes (37 %). Correlation between the Gram and acridine staining of the same sample was good (Spearman 0.85). Overall, the sensitivity, specificity, positive predictive value and negative predictive value of Gram stain for rapid diagnosis of septic arthritis was 0.37, 0.99, 0.99 and 0.28, respectively, compared to microbiological cultures. Quite similar values were recorded across the different patient subpopulations, in particular for sensitivity values that were 0.33 for patients with prosthetic joint infections, 0.40 for immunosuppressed patients, 0.36 for patients under antibiotic administration and 0.52 for patients with concomitant crystalline disease. The sensitivity of Gram or acridine orange staining for a rapid diagnosis of episodes of septic arthritis is suboptimal compared to microbiological culture, regardless of underlying conditions, immunosuppression or antibiotic therapy. The sensitivity in the presence of synovial fluid crystals is moderate. Acridine orange and Gram stains are equivalent.

  8. Gram stains: a resource for retrospective analysis of bacterial pathogens in clinical studies.

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    Srinivasan, Usha; Ponnaluri, Sreelatha; Villareal, Lisa; Gillespie, Brenda; Wen, Ai; Miles, Arianna; Bucholz, Brigette; Marrs, Carl F; Iyer, Ram K; Misra, Dawn; Foxman, Betsy

    2012-01-01

    We demonstrate the feasibility of using qPCR on DNA extracted from vaginal Gram stain slides to estimate the presence and relative abundance of specific bacterial pathogens. We first tested Gram stained slides spiked with a mix of 10(8) cfu/ml of Escherichia coli and 10(5) cfu/ml of Lactobacillus acidophilus. Primers were designed for amplification of total and species-specific bacterial DNA based on 16S ribosomal gene regions. Sample DNA was pre-amplified with nearly full length 16S rDNA ribosomal gene fragment, followed by quantitative PCR with genera and species-specific 16S rDNA primers. Pre-amplification PCR increased the bacterial amounts; relative proportions of Escherichia coli and Lactobacillus recovered from spiked slides remained unchanged. We applied this method to forty two archived Gram stained slides available from a clinical trial of cerclage in pregnant women at high risk of preterm birth. We found a high correlation between Nugent scores based on bacterial morphology of Lactobacillus, Gardenerella and Mobiluncus and amounts of quantitative PCR estimated genus specific DNA (rrn copies) from Gram stained slides. Testing of a convenience sample of eight paired vaginal swabs and Gram stains freshly collected from healthy women found similar qPCR generated estimates of Lactobacillus proportions from Gram stained slides and vaginal swabs. Archived Gram stained slides collected from large scale epidemiologic and clinical studies represent a valuable, untapped resource for research on the composition of bacterial communities that colonize human mucosal surfaces.

  9. Colistin: an antibiotic and its role in multiresistant Gram-negative infections.

    Science.gov (United States)

    Loho, Tonny; Dharmayanti, Anti

    2015-04-01

    Increasing number of infection cases caused by multiresistant Gram-negative bacteria or multidrug resistant organism (MDRO) has become a major problem worldwide since there have been a lot of resistance to many classes of antibiotics. Mutant isolates such as fluoroquinolone-resistant and -lactamase-resistant bacteria have been commonly found, particularly in intensive care unit (ICU). During the last two decades, there has been no study of developing antibiotics in search of discovering new type of antibiotics; meanwhile, the resistance of Gram-negative bacteria or MDRO to antibiotics is increasing. Colistin or polymyxin E is an old antibiotic, which has been used since 1959 for treating infection caused by Gram-negative MDRO. It was revealed that colistin has side effects of nephrotoxicity and neurotoxicity; therefore, the use of this antibiotic was stopped and it was replaced by other antibiotics which were effective and were considered safer at that time. There is an increasing number of infections with multi-resistant Gram-negative (MDRO) against the available antibiotics and the availability of alternative antibiotics has not been satisfying; therefore, microbiologists are searching back to the old option, which has been proven to be effective against multi-resistant Gram-negative bacteria, the old antibiotic that has been long forgotten, i.e. colistin, as an alternative treatment against Gram-negative MDRO. It is expected that colistin may have essential and reliable role as future antibiotics for treatment of multi-resistant Gram-negative infections and as an alternative of antibiotics that have been available so far.

  10. Phosphorus Response and Amino Acid Composition of Different Green Gram (Vigna radiata L. Genotypes from Myanmar

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    M. Kywe

    2007-10-01

    Full Text Available Mungbean or green gram (Vigna radiata L. is an important component of rice-based cropping systems in Myanmar, where grain yields of around 800 kg ha^(-1 are much below its yield potential of 3000 kg ha^(-1. The reasons for this shortfall are as under-investigated as is the genotype-specific response of this crop to phosphorus (P application, which is critically low in many Myanmar soils, and the genetic variation in grain quality. For green gram quality, the concentration of lysine, an essential amino acid is particularly important given its scarcity in many cereal-based diets of Southeast Asia. The purpose of this study therefore was to investigate the effects of P application on the root and shoot growth, yield and its components for a range of green gram varieties, and to analyse the protein concentration and amino acid composition in green gram seed of different origins. To this end from 2001 to 2003, field experiments were conducted under rain-fed conditions in Yezin and Nyaung Oo. Fifteen landraces and five introduced green gram cultivars were grown at two levels of P (0 and 15 kg ha^(-1. There were large genotypic differences in P effects and a significant interaction between green gram genotypes and P for shoot and root growth. An unexpected benefit of P application was a reduction of pest and plant virus infestation in the field. Significant genotypic differences in the amino acid profile of seeds were also observed. The results indicate the potential for breeding efforts to increase seed yield and protein quality in green gram.

  11. Utilizing Mars Global Reference Atmospheric Model (Mars-GRAM 2005) to Evaluate Entry Probe Mission Sites

    Science.gov (United States)

    Justh, Hilary L.; Justus, Carl G.

    2008-01-01

    The Mars Global Reference Atmospheric Model (Mars-GRAM 2005) is an engineering-level atmospheric model widely used for diverse mission applications. An overview is presented of Mars-GRAM 2005 and its new features. The "auxiliary profile" option is one new feature of Mars-GRAM 2005. This option uses an input file of temperature and density versus altitude to replace the mean atmospheric values from Mars-GRAM's conventional (General Circulation Model) climatology. Any source of data or alternate model output can be used to generate an auxiliary profile. Auxiliary profiles for this study were produced from mesoscale model output (Southwest Research Institute's Mars Regional Atmospheric Modeling System (MRAMS) model and Oregon State University's Mars mesoscale model (MMM5) model) and a global Thermal Emission Spectrometer (TES) database. The global TES database has been specifically generated for purposes of making Mars-GRAM auxiliary profiles. This data base contains averages and standard deviations of temperature, density, and thermal wind components, averaged over 5-by-5 degree latitude-longitude bins and 15 degree Ls bins, for each of three Mars years of TES nadir data. The Mars Science Laboratory (MSL) sites are used as a sample of how Mars-GRAM' could be a valuable tool for planning of future Mars entry probe missions. Results are presented using auxiliary profiles produced from the mesoscale model output and TES observed data for candidate MSL landing sites. Input parameters rpscale (for density perturbations) and rwscale (for wind perturbations) can be used to "recalibrate" Mars-GRAM perturbation magnitudes to better replicate observed or mesoscale model variability.

  12. Updating Mars-GRAM to Increase the Accuracy of Sensitivity Studies at Large Optical Depths

    Science.gov (United States)

    Justh, Hiliary L.; Justus, C. G.; Badger, Andrew M.

    2010-01-01

    The Mars Global Reference Atmospheric Model (Mars-GRAM) is an engineering-level atmospheric model widely used for diverse mission applications. Mars-GRAM s perturbation modeling capability is commonly used, in a Monte-Carlo mode, to perform high fidelity engineering end-to-end simulations for entry, descent, and landing (EDL). During the Mars Science Laboratory (MSL) site selection process, it was discovered that Mars-GRAM, when used for sensitivity studies for MapYear=0 and large optical depth values such as tau=3, is less than realistic. From the surface to 80 km altitude, Mars-GRAM is based on the NASA Ames Mars General Circulation Model (MGCM). MGCM results that were used for Mars-GRAM with MapYear set to 0 were from a MGCM run with a fixed value of tau=3 for the entire year at all locations. This has resulted in an imprecise atmospheric density at all altitudes. As a preliminary fix to this pressure-density problem, density factor values were determined for tau=0.3, 1 and 3 that will adjust the input values of MGCM MapYear 0 pressure and density to achieve a better match of Mars-GRAM MapYear 0 with Thermal Emission Spectrometer (TES) observations for MapYears 1 and 2 at comparable dust loading. Currently, these density factors are fixed values for all latitudes and Ls. Results will be presented from work being done to derive better multipliers by including variation with latitude and/or Ls by comparison of MapYear 0 output directly against TES limb data. The addition of these more precise density factors to Mars-GRAM 2005 Release 1.4 will improve the results of the sensitivity studies done for large optical depths.

  13. Improving Mars-GRAM: Increasing the Accuracy of Sensitivity Studies at Large Optical Depths

    Science.gov (United States)

    Justh, Hilary L.; Justus, C. G.; Badger, Andrew M.

    2010-01-01

    Extensively utilized for numerous mission applications, the Mars Global Reference Atmospheric Model (Mars-GRAM) is an engineering-level atmospheric model. In a Monte-Carlo mode, Mars-GRAM's perturbation modeling capability is used to perform high fidelity engineering end-to-end simulations for entry, descent, and landing (EDL). Mars-GRAM has been found to be inexact when used during the Mars Science Laboratory (MSL) site selection process for sensitivity studies for MapYear=0 and large optical depth values such as tau=3. Mars-GRAM is based on the NASA Ames Mars General Circulation Model (MGCM) from the surface to 80 km altitude. Mars-GRAM with the MapYear parameter set to 0 utilizes results from a MGCM run with a fixed value of tau=3 at all locations for the entire year. Imprecise atmospheric density and pressure at all altitudes is a consequence of this use of MGCM with tau=3. Density factor values have been determined for tau=0.3, 1 and 3 as a preliminary fix to this pressure-density problem. These factors adjust the input values of MGCM MapYear 0 pressure and density to achieve a better match of Mars-GRAM MapYear 0 with Thermal Emission Spectrometer (TES) observations for MapYears 1 and 2 at comparable dust loading. These density factors are fixed values for all latitudes and Ls and are included in Mars-GRAM Release 1.3. Work currently being done, to derive better multipliers by including variations with latitude and/or Ls by comparison of MapYear 0 output directly against TES limb data, will be highlighted in the presentation. The TES limb data utilized in this process has been validated by a comparison study between Mars atmospheric density estimates from Mars-GRAM and measurements by Mars Global Surveyor (MGS). This comparison study was undertaken for locations on Mars of varying latitudes, Ls, and LTST. The more precise density factors will be included in Mars-GRAM 2005 Release 1.4 and thus improve the results of future sensitivity studies done for large

  14. Appraising contemporary strategies to combat multidrug resistant gram-negative bacterial infections--proceedings and data from the Gram-Negative Resistance Summit.

    Science.gov (United States)

    Kollef, Marin H; Golan, Yoav; Micek, Scott T; Shorr, Andrew F; Restrepo, Marcos I

    2011-09-01

    The emerging problem of antibiotic resistance, especially among Gram-negative bacteria (GNB), has become a serious threat to global public health. Very few new antibacterial classes with activity against antibiotic-resistant GNB have been brought to market. Renewed and growing attention to the development of novel compounds targeting antibiotic-resistant GNB, as well as a better understanding of strategies aimed at preventing the spread of resistant bacterial strains and preserving the efficacy of existing antibiotic agents, has occurred. The Gram-Negative Resistance Summit convened national opinion leaders for the purpose of analyzing current literature, epidemiologic trends, clinical trial data, therapeutic options, and treatment guidelines related to the management of antibiotic-resistant GNB infections. After an in-depth analysis, the Summit investigators were surveyed with regard to 4 clinical practice statements. The results then were compared with the same survey completed by 138 infectious disease and critical care physicians and are the basis of this article.

  15. Myeloid cell sirtuin-1 expression does not alter host immune responses to Gram-negative endotoxemia or Gram-positive bacterial infection.

    Directory of Open Access Journals (Sweden)

    Laura E Crotty Alexander

    Full Text Available The role of sirtuin-1 (SIRT1 in innate immunity, and in particular the influence of SIRT1 on antimicrobial defense against infection, has yet to be reported but is important to define since SIRT1 inhibitors are being investigated as therapeutic agents in the treatment of cancer, Huntington's disease, and autoimmune diseases. Given the therapeutic potential of SIRT1 suppression, we sought to characterize the role of SIRT1 in host defense. Utilizing both pharmacologic methods and a genetic knockout, we demonstrate that SIRT1 expression has little influence on macrophage and neutrophil antimicrobial functions. Myeloid SIRT1 expression does not change mortality in gram-negative toxin-induced shock or gram-positive bacteremia, suggesting that therapeutic suppression of SIRT1 may be done safely without suppression of myeloid cell-specific immune responses to severe bacterial infections.

  16. Green Gram Rotation Effects on Maize Growth Parameters and Soil Quality in Myanmar

    Directory of Open Access Journals (Sweden)

    Myo Kywe

    2008-10-01

    Full Text Available At present maize–green gram crop rotations are not widely practiced among farmers in Myanmar. However, this cropping system might become more popular in the future given raising prices for green gram and maize grain and scarcity of mineral nitrogen (N fertilizers in this Asian country. The results of a cropping systems experiment with continuous maize versus a green gram-maize rotation, manure application (0 and 2 t ha−1 and phosphorus (P fertilization (0 and 15 kg P ha−1 in each of five consecutive seasons revealed a strong decline in total dry matter and grains yields for both crops irrespective of the treatment. Treatment effects on yield components, nutrient concentrations, mycorrhizal infection and nematode infestation were small or negligible. The data show that in addition to manure used at 2 t ha−1, application of mineral N fertilizers is essential to maintain particularly maize yields. A comparison of different green gram cultivars did not indicate genotype specific effects on maize growth. The incorporation of legume residues, unless they are used as animal feed, is recommended to increase the recycling of N and to balance N fluxes when green gram is cultivated for seed.

  17. Bruchid egg induced transcript dynamics in developing seeds of black gram (Vigna mungo.

    Directory of Open Access Journals (Sweden)

    Indrani K Baruah

    Full Text Available Black gram (Vigna mungo seeds are a rich source of digestible proteins, however, during storage these seeds are severely damaged by bruchids (Callosobruchus spp., reducing seed quality and yield losses. Most of the cultivated genotypes of black gram are susceptible to bruchids, however, few tolerant genotypes have also been identified but the mechanism of tolerance is poorly understood. We employed Suppression Subtractive Hybridization (SSH to identify specifically, but rarely expressed bruchid egg induced genes in black gram. In this study, Suppression Subtractive Hybridization (SSH library was constructed to study the genes involved in defense response in black gram against bruchid infestation. An EST library of 277 clones was obtained for further analyses. Based on CAP3 assembly, 134 unigenes were computationally annotated using Blast2GOPRO software. In all, 20 defense related genes were subject to quantitative PCR analysis (qPCR out of which 12 genes showed up-regulation in developing seeds of the pods oviposited by bruchids. Few major defense genes like defensin, pathogenesis related protein (PR, lipoxygenase (LOX showed high expression levels in the oviposited population when compared with the non-oviposited plants. This is the first report on defense related gene transcript dynamics during the bruchid-black gram interaction using SSH library. This library would be useful to clone defense related gene(s such as defensin as represented in our library for crop improvement.

  18. Earth Global Reference Atmospheric Model 2007 (Earth-GRAM07) Applications for the NASA Constellation Program

    Science.gov (United States)

    Leslie, Fred W.; Justus, C. G.

    2008-01-01

    Engineering models of the atmosphere are used extensively by the aerospace community for design issues related to vehicle ascent and descent. The Earth Global Reference Atmosphere Model version 2007 (Earth-GRAM07) is the latest in this series and includes a number of new features. Like previous versions, Earth-GRAM07 provides both mean values and perturbations for density, temperature, pressure, and winds, as well as monthly- and geographically-varying trace constituent concentrations. From 0 km to 27 km, thermodynamics and winds are based on the National Oceanic and Atmospheric Administration Global Upper Air Climatic Atlas (GUACA) climatology. For altitudes between 20 km and 120 km, the model uses data from the Middle Atmosphere Program (MAP). Above 120 km, EarthGRAM07 now provides users with a choice of three thermosphere models: the Marshall Engineering Thermosphere (MET-2007) model; the Jacchia-Bowman 2006 thermosphere model (JB2006); and the Naval Research Labs Mass Spectrometer, Incoherent Scatter Radar Extended Model (NRL MSIS E-OO) with the associated Harmonic Wind Model (HWM-93). In place of these datasets, Earth-GRAM07 has the option of using the new 2006 revised Range Reference Atmosphere (RRA) data, the earlier (1983) RRA data, or the user may also provide their own data as an auxiliary profile. Refinements of the perturbation model are also discussed which include wind shears more similar to those observed at the Kennedy Space Center than the previous version Earth-GRAM99.

  19. Estudo bacteriológico de lesões periapicais

    Directory of Open Access Journals (Sweden)

    ROCHA Márcia Maria de Negreiros Pinto

    1998-01-01

    Full Text Available O tecido perirradicular de 30 casos cirúrgicos foi submetido a exame microbiológico e histopatológico. Foram isoladas 137 cepas bacterianas das 30 lesões periapicais estudadas. Do total de bactérias isoladas, 90 (65,7% foram caracterizadas como anaeróbias estritas, 40 (29,2% como anaeróbias facultativas e 7 (5,1% como aeróbias estritas. Fusobacterium nucleatum, bacilos Gram-negativos pigmentados anaeróbios estritos, Peptostreptococcus sp, Streptococcus mitis e bacilos Gram-positivos não esporulados anaeróbios estritos foram, em ordem decrescente de freqüência, as bactérias mais comumente isoladas das lesões periapicais. A análise histopatológica demonstrou prevalência de granuloma periapical. O estudo de sensibilidade a antimicrobianos foi realizado em 16 cepas de Fusobacterium nucleatum. Os antimicrobianos utilizados foram penicilina, cefoxitina, eritromicina, metronidazol e tetraciclina. Todas as amostras apresentaram suscetibilidade à cefoxitina, tetraciclina e metronidazol; os percentuais de resistência à penicilina e à eritromicina foram 12,5 e 68,8, respectivamente. Os percentuais de resistência de Fusobacterium nucleatum, uma espécie bacteriana importante na patogênese das lesões periapicais, à penicilina e à eritromicina, enfatizam a necessidade de outros estudos de resistência a antimicrobianos de bactérias isoladas em infecções odontogênicas.

  20. A 15 year-review of peritoneal dialysis-related peritonitis: Microbiological trends and patterns of infection in a teaching hospital in Argentina Peritonitis en diálisis peritoneal: características microbiológicas y patrones de infección a lo largo de 15 años en un hospital universitario en Argentina

    Directory of Open Access Journals (Sweden)

    J. E. Santoianni

    2008-03-01

    álisis peritoneal durante los últimos 15 años. Se evaluaron evolución clínica, infecciones del sitio de salida y del túnel, y los microorganismos causales y su sensibilidad, a fin de seleccionar la mejor terapia empírica para nuestro centro. Se realizaron dos procedimientos microbiológicos, método A: 100 ml del dializado fueron centrifugados y cultivados por métodos convencionales y en frascos para hemocultivo; método B: 10 ml fueron directamente inoculados en frascos para hemocultivo. Los hisopados del sitio de salida y del túnel fueron realizados cuando se observó supuración. Se registraron 96 episodios de peritonitis en 110,43 paciente-años (0,87 episodios/paciente-año. La sensibilidad del método A fue 96,88% versus 81,25% del método B (p = 0,001. La sensibilidad de la coloración de Gram fue 36,46%. La distribución de los agentes etiológicos fue la siguiente: 64 (56,64% cocos gram-positivos, 22 (19,47% bacilos gram-negativos fermentadores, 20 (17,7% bacilos gram-negativos no fermentadores, 5 (4,43% levaduras, 1 (0,88% hongo micelial, 1 (0,88% bacilo anaerobio. Fueron documentadas 55 infecciones del sitio de salida (0,5 episodios/paciente-año. La ceftazidima y el imipenem mostraron una excelente actividad sobre los bacilos gram-negativos. La sensibilidad a meticilina fue de 92,3% para Staphylococcus aureus y 33,3% para estafilococos coagulasa negativos; la vancomicina fue activa frente al 100% de los cocos gram-positivos. La evolución clínica de las peritonitis fue: 73 curas, 19 remociones de catéter y cuatro muertes relacionadas. La terapia empírica en nuestro centro debería ser vancomicina más ceftazidima o imipenem. Una vez conocidos el agente etiológico y su sensibilidad, se debería aplicar la terapia de desescalonamiento para evitar la emergencia y diseminación de microorganismos resistentes a la vancomicina.

  1. Serum procalcitonin elevation in critically ill patients at the onset of bacteremia caused by either Gram negative or Gram positive bacteria.

    Science.gov (United States)

    Charles, Pierre Emmanuel; Ladoire, Sylvain; Aho, Serge; Quenot, Jean-Pierre; Doise, Jean-Marc; Prin, Sébastien; Olsson, Niels-Olivier; Blettery, Bernard

    2008-03-26

    In the ICU, bacteremia is a life-threatening infection whose prognosis is highly dependent on early recognition and treatment with appropriate antibiotics. Procalcitonin levels have been shown to distinguish between bacteremia and noninfectious inflammatory states accurately and quickly in critically ill patients. However, we still do not know to what extent the magnitude of PCT elevation at the onset of bacteremia varies according to the Gram stain result. Review of the medical records of every patient treated between May, 2004 and December, 2006 who had bacteremia caused by either Gram positive (GP) or Gram negative (GN) bacteria, and whose PCT dosage at the onset of infection was available. 97 episodes of either GN bacteremia (n = 52) or GP bacteremia (n = 45) were included. Procalcitonin levels were found to be markedly higher in patients with GN bacteremia than in those with GP bacteremia, whereas the SOFA score value in the two groups was similar. Moreover, in the study population, a high PCT value was found to be independently associated with GN bacteremia. A PCT level of 16.0 ng/mL yielded an 83.0% positive predictive value and a 74.0% negative predictive value for GN-related bacteremia in the study cohort (AUROCC = 0.79; 95% CI, 0.71-0.88). In a critically ill patient with clinical sepsis, GN bacteremia could be associated with higher PCT values than those found in GP bacteremia, regardless of the severity of the disease.

  2. Measuring the Level of Agreement Between Cloacal Gram's Stains and Bacterial Cultures in Hispaniolan Amazon Parrots ( Amazona ventralis ).

    Science.gov (United States)

    Evans, Erika E; Mitchell, Mark A; Whittington, Julia K; Roy, Alma; Tully, Thomas N

    2014-12-01

    Cloacal or fecal Gram's stains and bacterial cultures are routinely performed during avian physical examinations to assess the microbial flora of the gastrointestinal tract. Although cloacal or fecal Gram's stains and bacterial cultures are considered routine diagnostic procedures, the level of agreement between the individual tests has not been determined. To investigate the level of agreement between results from Gram's stain and bacterial culture when used to assess cloacal or fecal samples from psittacine birds, samples were taken from 21 clinically healthy Hispaniolan Amazon parrots ( Amazona ventralis ) and tested by Gram's stain cytology and bacterial culture. Most bacteria (97.2%) identified by Gram's stain were gram positive. However, gram-negative organisms were identified in 7 of 21 (33.3%; 95% confidence interval: 13.3%-53.3%) birds. Escherichia coli was the only gram-negative organism identified on culture. Agreement between results of Gram's stain and culture was fair (weighted κ = 0.27). The results of this study suggest that Gram's stains and bacterial culture may need to be performed with a parallel testing strategy to limit the likelihood of misclassifying the microbial flora of psittacine patients.

  3. Actividad “in vitro” de 10 antimicrobianos frente a bacterias anaerobias: Estudio multicéntrico, 1999-2002 “In vitro” activity of ten antimicrobial agents against anaerobic bacteria. A collaborative study, 1999-2002

    Directory of Open Access Journals (Sweden)

    M. Litterio

    2004-09-01

    Full Text Available Se evaluó la actividad de ampicilina, ampicilina-sulbactama, cefoxitina, ceftriaxona, imipenem, piperacilina, piperacilina-tazobactama, clindamicina, metronidazol y azitromicina frente a 166 cepas de bacterias anaerobias aisladas en 8 hospitales de Buenos Aires. Se estudiaron: Bacteroides grupo fragilis (65, Fusobacterium spp. (26, Prevotella spp. (21, Porphyromonas spp. (10, Clostridium difficile (10, otros clostridios (12 y cocos gram-positivos (22. Las CIMs se determinaron usando el método patrón de dilución en agar recomendado por el NCCLS, documento M11-A5. Los antibióticos más activos fueron metronidazol y piperacilina-tazobactama que exhibieron valores de CIM90£ 2 µg/ml y £ 4 µg/ml frente a los microorganismos gram-negativos y £ 2 µg/ml y £ 8 µg/ml frente a los microorganismos gram-positivos, respectivamente. Entre los b-lactámicos el orden de actividad frente a bacilos gram-negativos fue: imipenem > piperacilina > cefoxitina > ceftriaxona > ampicilina. En gram-positivos la actividad decreciente fue: piperacilina> imipenem > cefoxitina > ceftriaxona > ampicilina. La mayoría de las especies estudiadas mostraron distintos niveles de resistencia con clindamicina y azitromicina. Sin embargo, el 90% de las cepas de Fusobacterium nucleatum y Por-phyromonas spp. fue inhibido por una concentración de 0,125 µg/ml de clindamicina y azitromicina, respectivamente.The antimicrobial activity of ampicillin, ampicillin-sulbactam, cefoxitin, ceftriaxone, imipenem, piperacillin, piperacillin-tazobactam, clindamycin, metronidazole, and azitromycin was assesed against 166 strains of anaerobic bacteria recovered from eight hospitals in Buenos Aires. The strains studied were Bacteroidesfragilis group (65, Fusobacterium spp. (26, Prevotella spp. (21, Porphyromonas spp. (10, Clostridium difficile (10, other clostridia (12, and gram-positive cocci (22. The MICs were determined by the agar dilution method according to NCCLS document M11-A5

  4. Utility of gram stain in evaluation of sputa from patients with cystic fibrosis.

    Science.gov (United States)

    Sadeghi, E; Matlow, A; MacLusky, I; Karmali, M A

    1994-01-01

    The utility of sputum Gram stain in assessing salivary contamination and in predicting the presence of pathogens on the basis of morphology was investigated in 287 respiratory specimens from patients with cystic fibrosis. Where acceptability for culture was defined as a leukocyte/squamous epithelial cell ratio of > 5, 76.6% (220 of 287) of respiratory specimens received in the laboratory were considered acceptable. Unacceptable specimens were more common in younger patients. The positive predictive value of the Gram stain for growth from acceptable sputum samples was 98% for Pseudomonas aeruginosa, 84.4% for Pseudomonas cepacia, 86.3% for Staphylococcus aureus, and 100% for Haemophilus influenzae. In cystic fibrosis patients, as has been reported for respiratory specimens in general, Gram stain of respiratory specimens in helpful for interpreting culture results. PMID:7510312

  5. Impact of reporting gram stain results from blood culture bottles on the selection of antimicrobial agents.

    Science.gov (United States)

    Uehara, Yuki; Yagoshi, Michiko; Tanimichi, Yumiko; Yamada, Hiroko; Shimoguchi, Kazuo; Yamamoto, Sachiyo; Yanai, Mitsuru; Kumasaka, Kazunari

    2009-07-01

    We assessed the usefulness of reporting direct blood Gram stain results compared with the results of positive blood cultures in 482 episodes and monitored impact on selection of antimicrobial treatment. We found that the reporting groups "Staphylococcus spp," "Pseudomonas spp and related organisms," and "yeasts" identified in this way matched perfectly with later culture identification. When the report indicated Staphylococcus spp or Pseudomonas spp and related organisms, physicians started or changed antimicrobials suitable for these bacteria more frequently than when "other streptococci" and "family Enterobacteriaceae" were reported (P Gram stain results that definitively identify Staphylococcus spp, Pseudomonas spp and related organisms, and yeasts reliably can be rapidly provided by clinical laboratories; this information has a significant impact on early selection of effective antimicrobials. Further investigation is needed to assess the clinical impact of reporting Gram stain results in bacteremia.

  6. Nucleotide sequence alignment of hdcA from Gram-positive bacteria.

    Science.gov (United States)

    Diaz, Maria; Ladero, Victor; Redruello, Begoña; Sanchez-Llana, Esther; Del Rio, Beatriz; Fernandez, Maria; Martin, Maria Cruz; Alvarez, Miguel A

    2016-03-01

    The decarboxylation of histidine -carried out mainly by some gram-positive bacteria- yields the toxic dietary biogenic amine histamine (Ladero et al. 2010 〈10.2174/157340110791233256〉 [1], Linares et al. 2016 〈http://dx.doi.org/10.1016/j.foodchem.2015.11.013〉〉 [2]). The reaction is catalyzed by a pyruvoyl-dependent histidine decarboxylase (Linares et al. 2011 〈10.1080/10408398.2011.582813〉 [3]), which is encoded by the gene hdcA. In order to locate conserved regions in the hdcA gene of Gram-positive bacteria, this article provides a nucleotide sequence alignment of all the hdcA sequences from Gram-positive bacteria present in databases. For further utility and discussion, see 〈http://dx.doi.org/ 10.1016/j.foodcont.2015.11.035〉〉 [4].

  7. Efficient n-gram, Skipgram and Flexgram Modelling with Colibri Core

    Directory of Open Access Journals (Sweden)

    Maarten van Gompel

    2016-08-01

    Full Text Available Counting n-grams lies at the core of any frequentist corpus analysis and is often considered a trivial matter. Going beyond consecutive n-grams to patterns such as skipgrams and flexgrams increases the demand for efficient solutions. The need to operate on big corpus data does so even more. Lossless compression and non-trivial algorithms are needed to lower the memory demands, yet retain good speed. Colibri Core is software for the efficient computation and querying of n-grams, skipgrams and flexgrams from corpus data. The resulting pattern models can be analysed and compared in various ways. The software offers a programming library for C++ and Python, as well as command-line tools.

  8. STUDY ON SURGICAL SITE INFECTIONS CAUSED BY ESBL PRODUCING GRAM NEGATIVE BACTERIA

    Directory of Open Access Journals (Sweden)

    Rambabu

    2015-09-01

    Full Text Available Surgical site infections have been a major problem, because of the emergence of drug resistant bacteria, in particular B - lactamase producing bacteria. Extended spectrum beta lactamase producing gram negative organisms pose a great challenge in treatment o f SSI present study is aimed at determining multiple drug resistance in gram negative bacteria & to find out ESBL producers, in correlation with treatment outcome. A total of 120 wound infected cases were studied. Staphylococcus aureus was predominant bact erium - 20.Among gram negative bacteria, Pseudomonas species is predominant (14 followed by Escherichia coli (13 , Klebsiella species (12 , Proteus (9 Citrobacter (4 Providencia (2 & Acinetobacter species (2 . Out of 56 gramnegative bacteria isolated, 20 were i dentified as ESBL producers, which was statistically significant. Delay in wound healing correlated with infection by ESBL producers, which alarms the need of abstinence from antibiotic abuse

  9. Nucleotide sequence alignment of hdcA from Gram-positive bacteria

    Directory of Open Access Journals (Sweden)

    Maria Diaz

    2016-03-01

    Full Text Available The decarboxylation of histidine -carried out mainly by some gram-positive bacteria- yields the toxic dietary biogenic amine histamine (Ladero et al. 2010 〈10.2174/157340110791233256〉 [1], Linares et al. 2016 〈http://dx.doi.org/10.1016/j.foodchem.2015.11.013〉〉 [2]. The reaction is catalyzed by a pyruvoyl-dependent histidine decarboxylase (Linares et al. 2011 〈10.1080/10408398.2011.582813〉 [3], which is encoded by the gene hdcA. In order to locate conserved regions in the hdcA gene of Gram-positive bacteria, this article provides a nucleotide sequence alignment of all the hdcA sequences from Gram-positive bacteria present in databases. For further utility and discussion, see 〈http://dx.doi.org/ 10.1016/j.foodcont.2015.11.035〉〉 [4].

  10. Prediction of groundwater rebound at an abandoned coal mine in Korea using GRAM model

    Science.gov (United States)

    Park, S.; Choi, Y.; Baek, H.; Shin, S.

    2013-12-01

    Cessation of dewatering generally results in groundwater rebound after closing an abandoned underground coal mine since the mine voids and surrounding strata flood up to the levels of decant points such as shafts and drifts. Several models such as VSS-NET, GRAM and MODFLOW have been developed to predict the timing, magnitude and location of discharges resulting from groundwater rebound. This study developed a GRAM model-based program was developed for ground water rebound modeling in abandoned deep mine systems after mine closure. An application of the program to the Dongwon coal mine in Korea showed that the groundwater level modeled at the shaft of Dongwon coal mine is similar to the observed one in the field. The GRAM model-based program is transferable to other mining areas in both industrialized and less-developed countries. Therefore, the program could reduce the time and effort for predicting mine groundwater rebound and to support mine reclamation planning.

  11. Gram-typing of mastitis bacteria in milk samples using flow cytometry

    DEFF Research Database (Denmark)

    Langerhuus, Sine Nygaard; Ingvartsen, Klaus Lønne; Bennedsgaard, Torben Werner

    2013-01-01

    identification of bacterial pathogens, although shipment of samples to diagnostic laboratories delays treatment decisions. Due to the lack of fast on-site tests that can identify the causative pathogens, antibiotic treatments are often initiated before bacterial identification. The present study describes a flow...... characteristic curves for the 19 bacterial cultures. The method was then tested on 53 selected mastitis cases obtained from the department biobank (milk samples from 6 gram-negative and 47 gram-positive mastitis cases). Gram-negative bacteria in milk samples were detected with a sensitivity of 1......Fast identification of pathogenic bacteria in milk samples from cows with clinical mastitis is central to proper treatment. In Denmark, time to bacterial diagnosis is typically 24 to 48 h when using traditional culturing methods. The PCR technique provides a faster and highly sensitive...

  12. [Antimicrobial therapy in severe infections with multidrug-resistant Gram-negative bacterias].

    Science.gov (United States)

    Duszyńska, Wiesława

    2010-01-01

    Multidrug-resistant Gram-negative bacteria pose a serious and rapidly emerging threat to patients in healthcare settings, and are especially prevalent and problematic in intensive therapy units. Recently, the emergence of pandrug-resistance in Gram-negative bacteria poses additional concerns. This review examines the clinical impact and epidemiology of multidrug-resistant Gram-negative bacteria as a cause of increased morbidity and mortality among ITU patients. Beta-lactamases, cephalosporinases and carbapenemases play the most important role in resistance to antibiotics. Despite the tendency to increased resistance, carbapenems administered by continuous infusion remain the most effective drugs in severe sepsis. Drug concentration monitoring, albeit rarely used in practice, is necessary to ensure an effective therapeutic effect.

  13. c-di-GMP Regulates Various Phenotypes and Insecticidal Activity of Gram-Positive Bacillus thuringiensis

    Directory of Open Access Journals (Sweden)

    Yang Fu

    2018-02-01

    Full Text Available C-di-GMP has been well investigated to play significant roles in the physiology of many Gram-negative bacteria. However, its effect on Gram-positive bacteria is less known. In order to more understand the c-di-GMP functions in Gram-positive bacteria, we have carried out a detailed study on the c-di-GMP-metabolizing enzymes and their physiological functions in Bacillus thuringiensis, a Gram-positive entomopathogenic bacterium that has been applied as an insecticide successfully. We performed a systematic study on the ten putative c-di-GMP-synthesizing enzyme diguanylate cyclases (DGCs and c-di-GMP-degrading enzyme phosphodiesterases (PDEs in B. thuringiensis BMB171, and artificially elevated the intracellular c-di-GMP level in BMB171 by deleting one or more pde genes. We found increasing level of intracellular c-di-GMP exhibits similar activities as those in Gram-negative bacteria, including altered activities in cell motility, biofilm formation, and cell-cell aggregation. Unexpectedly, we additionally found a novel function exhibited by the increasing level of c-di-GMP to promote the insecticidal activity of this bacterium against Helicoverpa armigera. Through whole-genome transcriptome profile analyses, we found that 4.3% of the B. thuringiensis genes were differentially transcribed when c-di-GMP level was increased, and 77.3% of such gene products are involved in some regulatory pathways not reported in other bacteria to date. In summary, our study represents the first comprehensive report on the c-di-GMP-metabolizing enzymes, their effects on phenotypes, and the transcriptome mediated by c-di-GMP in an important Gram-positive bacterium.

  14. The limitations of Gram-stain microscopy of synovial fluid in concomitant septic and crystal arthritis.

    Science.gov (United States)

    Stirling, Paul; Tahir, Mohammed; Atkinson, Henry Dushan

    2017-03-29

    Rapid diagnosis of septic arthritis from Gram-stain microscopy is limited by an inherent false-negative rate of 25-78%. The presence of concomitant crystal arthritis in 5% of cases represents a particular diagnostic challenge. This study aims to investigate the effects that a concomitant crystal arthropathy have on the ability of Gram-stain microscopy of synovial fluid to diagnose a septic arthritis. This is a 12-year retrospective cohort study. Inclusion criteria were a positive synovial fluid culture result with a positive clinical diagnosis of septic arthritis. Results were correlated with presence or absence of urate and calcium pyrophosphate crystals, and Gram-stain result. During this time our collection and analysis methods remained unchanged. All samples were collected in Lithium Heparin containers. Chi-squared test with a p value < 0.05 was considered significant. 602 synovial fluid samples were included. 162 cases of concomitant crystal arthritis were identified (27%). Of these, 16 (10%) had an initial negative Gram-stain. Of the 440 samples with no crystals detected, 18 (4%) had an initial negative Gram-stain microscopy result (p < 0.05). The incidence of concurrent septic and crystal arthritis may be higher than previously thought. Synovial fluid samples in concomitant septic and crystal arthritis are significantly less likely to have a positive Gram-stain at microscopy than in cases of an isolated septic arthritis. We would advise the clinician to maintain a high index of suspicion for septic arthritis in these patients. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Periprosthetic infection: where do we stand with regard to Gram stain?

    Science.gov (United States)

    Ghanem, Elie; Ketonis, Constantinos; Restrepo, Camilo; Joshi, Ashish; Barrack, Robert; Parvizi, Javad

    2009-02-01

    One of the routinely used intraoperative tests for diagnosis of periprosthetic infection (PPI) is the Gram stain. It is not known if the result of this test can vary according to the type of joint affected or the number of specimen samples collected. We examined the role of this diagnostic test in a large cohort of patients from a single institution. A positive gram stain was defined as the visualization of bacterial cells or "many neutrophils" (> 5 per high-power field) in the smear. The sensitivity, specificity, and predictive values of each individual diagnostic arm of Gram stain were determined. Combinations were performed in series, which required both tests to be positive to confirm infection, and also in parallel, which necessitated both tests to be negative to rule out infection. The presence of organisms and "many" neutrophils on a Gram smear had high specificity (98-100%) and positive predictive value (89-100%) in both THA and TKA. The sensitivities (30-50%) and negative predictive values (70-79%) of the 2 tests were low for both joint types. When the 2 tests were combined in series, the specificity and positive predictive value were absolute (100%). The sensitivity and the negative predictive value improved for both THA and TKA (43-64% and 82%, respectively). Although the 2 diagnostic arms of Gram staining can be combined to achieve improved negative predictive value (82%), Gram stain continues to have little value in ruling out PPI. With the advances in the field of molecular biology, novel diagnostic modalities need to be designed that can replace these traditional and poor tests.

  16. c-di-GMP Regulates Various Phenotypes and Insecticidal Activity of Gram-Positive Bacillus thuringiensis

    Science.gov (United States)

    Fu, Yang; Yu, Zhaoqing; Liu, Shu; Chen, Bo; Zhu, Li; Li, Zhou; Chou, Shan-Ho; He, Jin

    2018-01-01

    C-di-GMP has been well investigated to play significant roles in the physiology of many Gram-negative bacteria. However, its effect on Gram-positive bacteria is less known. In order to more understand the c-di-GMP functions in Gram-positive bacteria, we have carried out a detailed study on the c-di-GMP-metabolizing enzymes and their physiological functions in Bacillus thuringiensis, a Gram-positive entomopathogenic bacterium that has been applied as an insecticide successfully. We performed a systematic study on the ten putative c-di-GMP-synthesizing enzyme diguanylate cyclases (DGCs) and c-di-GMP-degrading enzyme phosphodiesterases (PDEs) in B. thuringiensis BMB171, and artificially elevated the intracellular c-di-GMP level in BMB171 by deleting one or more pde genes. We found increasing level of intracellular c-di-GMP exhibits similar activities as those in Gram-negative bacteria, including altered activities in cell motility, biofilm formation, and cell-cell aggregation. Unexpectedly, we additionally found a novel function exhibited by the increasing level of c-di-GMP to promote the insecticidal activity of this bacterium against Helicoverpa armigera. Through whole-genome transcriptome profile analyses, we found that 4.3% of the B. thuringiensis genes were differentially transcribed when c-di-GMP level was increased, and 77.3% of such gene products are involved in some regulatory pathways not reported in other bacteria to date. In summary, our study represents the first comprehensive report on the c-di-GMP-metabolizing enzymes, their effects on phenotypes, and the transcriptome mediated by c-di-GMP in an important Gram-positive bacterium. PMID:29487570

  17. c-di-GMP Regulates Various Phenotypes and Insecticidal Activity of Gram-PositiveBacillus thuringiensis.

    Science.gov (United States)

    Fu, Yang; Yu, Zhaoqing; Liu, Shu; Chen, Bo; Zhu, Li; Li, Zhou; Chou, Shan-Ho; He, Jin

    2018-01-01

    C-di-GMP has been well investigated to play significant roles in the physiology of many Gram-negative bacteria. However, its effect on Gram-positive bacteria is less known. In order to more understand the c-di-GMP functions in Gram-positive bacteria, we have carried out a detailed study on the c-di-GMP-metabolizing enzymes and their physiological functions in Bacillus thuringiensis , a Gram-positive entomopathogenic bacterium that has been applied as an insecticide successfully. We performed a systematic study on the ten putative c-di-GMP-synthesizing enzyme diguanylate cyclases (DGCs) and c-di-GMP-degrading enzyme phosphodiesterases (PDEs) in B. thuringiensis BMB171, and artificially elevated the intracellular c-di-GMP level in BMB171 by deleting one or more pde genes. We found increasing level of intracellular c-di-GMP exhibits similar activities as those in Gram-negative bacteria, including altered activities in cell motility, biofilm formation, and cell-cell aggregation. Unexpectedly, we additionally found a novel function exhibited by the increasing level of c-di-GMP to promote the insecticidal activity of this bacterium against Helicoverpa armigera . Through whole-genome transcriptome profile analyses, we found that 4.3% of the B. thuringiensis genes were differentially transcribed when c-di-GMP level was increased, and 77.3% of such gene products are involved in some regulatory pathways not reported in other bacteria to date. In summary, our study represents the first comprehensive report on the c-di-GMP-metabolizing enzymes, their effects on phenotypes, and the transcriptome mediated by c-di-GMP in an important Gram-positive bacterium.

  18. A synbio approach for selection of highly expressed gene variants in Gram-positive bacteria

    DEFF Research Database (Denmark)

    Ferro, Roberto; Rennig, Maja; Hernández Rollán, Cristina

    2018-01-01

    The market for recombinant proteins is on the rise, and Gram-positive strains are widely exploited for this purpose. Bacillus subtilis is a profitable host for protein production thanks to its ability to secrete large amounts of proteins, and Lactococcus lactis is an attractive production organism....... subtilis and tyrosine ammonia lyase in L. lactis. Gram-positive bacteria are widely used to produce industrial enzymes. High titres are necessary to make the production economically feasible. The synbio approach presented here is a simple and inexpensive way to increase protein titres, which can be carried...

  19. Numerically Stable Evaluation of Moments of Random Gram Matrices With Applications

    KAUST Repository

    Elkhalil, Khalil

    2017-07-31

    This paper focuses on the computation of the positive moments of one-side correlated random Gram matrices. Closed-form expressions for the moments can be obtained easily, but numerical evaluation thereof is prone to numerical stability, especially in high-dimensional settings. This letter provides a numerically stable method that efficiently computes the positive moments in closed-form. The developed expressions are more accurate and can lead to higher accuracy levels when fed to moment based-approaches. As an application, we show how the obtained moments can be used to approximate the marginal distribution of the eigenvalues of random Gram matrices.

  20. Identification of a d-Arabinose-5-Phosphate Isomerase in the Gram-Positive Clostridium tetani.

    Science.gov (United States)

    Cech, David L; Markin, Katherine; Woodard, Ronald W

    2017-09-01

    d-Arabinose-5-phosphate (A5P) isomerases (APIs) catalyze the interconversion of d-ribulose-5-phosphate and d-arabinose-5-phosphate. Various Gram-negative bacteria, such as the uropathogenic Escherichia coli strain CFT073, contain multiple API paralogs (KdsD, GutQ, KpsF, and c3406) that have been assigned various cellular functions. The d-arabinose-5-phosphate formed by these enzymes seems to play important roles in the biosynthesis of lipopolysaccharide (LPS) and group 2 K-antigen capsules, as well as in the regulation of the cellular d-glucitol uptake and uropathogenic infectivity/virulence. The genome of a Gram-positive pathogenic bacterium, Clostridium tetani , contains a gene encoding a putative API, C. tetani API (CtAPI), even though C. tetani lacks both LPS and capsid biosynthetic genes. To better understand the physiological role of d-arabinose-5-phosphate in this Gram-positive organism, recombinant CtAPI was purified and characterized. CtAPI displays biochemical characteristics similar to those of APIs from Gram-negative organisms and complements the API deficiency of an E. coli API knockout strain. Thus, CtAPI represents the first d-arabinose-5-phosphate isomerase to be identified and characterized from a Gram-positive bacterium. IMPORTANCE The genome of Clostridium tetani , a pathogenic Gram-positive bacterium and the causative agent of tetanus, contains a gene (the CtAPI gene) that shares high sequence similarity with those of genes encoding d-arabinose-5-phosphate isomerases. APIs play an important role within Gram-negative bacteria in d-arabinose-5-phosphate production for lipopolysaccharide biosynthesis, capsule formation, and regulation of cellular d-glucitol uptake. The significance of our research is in identifying and characterizing CtAPI, the first Gram-positive API. Our findings show that CtAPI is specific to the interconversion of arabinose-5-phosphate and ribulose-5-phosphate while having no activity with the other sugars and sugar phosphates

  1. Determining source cumulants in femtoscopy with Gram-Charlier and Edgeworth series

    DEFF Research Database (Denmark)

    Schmiegel, Jürgen; Eggers, Hans C.; de Kock, Michiel B

    Lowest-order cumulants provide important information on the shape of the emission source in femtoscopy. For the simple case of noninteracting identical particles, we show how the fourth-order source cumulant can be determined from measured cumulants in momentum space. The textbook Gram-Charlier s......Lowest-order cumulants provide important information on the shape of the emission source in femtoscopy. For the simple case of noninteracting identical particles, we show how the fourth-order source cumulant can be determined from measured cumulants in momentum space. The textbook Gram...

  2. Fatores associados à agressão física em gestantes e os desfechos negativos no recém-nascido Factors associated with physical aggression in pregnant women and adverse outcomes for the newborn

    Directory of Open Access Journals (Sweden)

    Elaine Fernandes Viellas

    2013-02-01

    Full Text Available OBJETIVO: Verificar os fatores socioeconômicos, demográficos e reprodutivos associados à agressão física na gestação e os desfechos negativos para o recém-nascido em dois grupos de mulheres: adolescentes e adultas jovens. MÉTODO: Estudo transversal com uma amostra de 8.961 puérperas que se hospitalizaram em maternidades do município do Rio de Janeiro por ocasião do parto. Para testar hipótese de homogeneidade de proporções foi utilizado o teste χ². A razão de chances e os intervalos de confiança foram estimados através de regressão logística. RESULTADOS: Foi apontado que 5% das adolescentes e 2,5% das adultas jovens sofreram agressão física na gravidez. Em ambos os grupos, as variáveis associadas com o abuso físico foram: menor nível de escolaridade, menor apoio do pai da criança e maior tentativa de interrupção da gestação. O aumento no consumo de bebida alcoólica mostrou associação com o abuso físico apenas no grupo de adolescentes, e o uso de drogas ilícitas somente entre as adultas jovens. Os filhos das puérperas agredidas tiveram duas vezes mais chances de óbito neonatal, e três vezes mais de óbito pós-neonatal. Por outro lado, a assistência pré-natal de boa qualidade reduziu a chance de agressão física durante a gestação. CONCLUSÕES: Os resultados alertam para o aumento da chance de óbito neonatal e pós-neonatal entre os filhos das vítimas de agressão física durante a gestação e apontam para a importância do pré-natal na identificação de mulheres sob maior risco de episódios violentos, momento oportuno para o desenvolvimento de ações de proteção e cuidado à mãe e ao bebê.OBJECTIVE: To assess the socioeconomic, demographic, and reproductive factors associated with physical aggression during pregnancy, and the negative outcomes for the newborn in two groups of women: adolescents and young adults. METHOD: Cross-sectional study with a sample of 8,961 mothers who were admitted

  3. Cataloguing, screening and assessing the effect of sowing time on the incidence of black gram pests under dryland condition

    Directory of Open Access Journals (Sweden)

    C. Gailce Leo Justin

    2015-12-01

    Full Text Available Cataloguing of different insect pests occurring in black gram, screening of black gram genotypes against major insect pests and their incidence on black gram at three different sowing times were investigated at Agricultural Research Station Farm, Tamil Nadu Agricultural University, Kovilpatti, Tuticorin District. Totally, 11 species of insect pests were identified in black gram ecosystem. Among the 10 black gram genotypes screened, KBG 06 016 recorded minimum population of leafhoppers during both the years and KBG 05 007 and KBG 06 021 showed minimum population of aphid during 2010–2011 and 2011–2012, respectively. The minimum damage by pod borer was noticed in KBG 04 003 and KBG 08 001 during 2010–2011 and 2011–2012, respectively. The minimum number of leafhoppers, aphids and pod borers were observed in monsoon, post-monsoon and pre-monsoon sown black gram, respectively.

  4. Extracellular Vesicles Produced by the Gram-positive Bacterium Bacillus subtilis are Disrupted by the Lipopeptide Surfactin

    OpenAIRE

    Brown, Lisa; Kessler, Anne; Cabezas-Sanchez, Pablo; Luque-Garcia, Jose L.; Casadevall, Arturo

    2014-01-01

    Previously, extracellular vesicle production in Gram-positive bacteria was dismissed due to the absence of an outer membrane, where Gram-negative vesicles originate, and the difficulty in envisioning how such a process could occur through the cell wall. However, recent work has shown that Gram-positive bacteria produce extracellular vesicles and that the vesicles are biologically active. In this study, we show that Bacillus subtilis produces extracellular vesicles similar in...

  5. Characterization of Extremely Lightweight Intrusion Detection (ELIDe) Power Utilization by Varying N-gram and Hash Length

    Science.gov (United States)

    2015-09-01

    Utilization by Varying N- gram and Hash Length by Garrett S Payer, Ken F Yu, and Richard E Harang Approved for public... gram and Hash Length by Garrett S Payer, Ken F Yu, and Richard E Harang Computational and Information Sciences Directorate, ARL...Characterization of Extremely Lightweight Intrusion Detection (ELIDe) Power Utilization by Varying N- gram and Hash Length 5a. CONTRACT NUMBER 5b. GRANT

  6. The usefulness of changing focus during examination using Gram staining as initial diagnostic clue for infective tuberculosis.

    Science.gov (United States)

    Atsukawa, Yoshiko; Kawakami, Sayoko; Asahara, Miwa; Ishigaki, Shinobu; Tanaka, Takashi; Ono, Yasuo; Nishiya, Hajime; Fujisaki, Ryuichi; Koga, Ichiro; Ota, Yasuo; Miyazawa, Yukihisa

    2011-08-01

    Gram staining is a useful technique for detecting bacteria but is highly questionable in detecting Mycobacterium tuberculosis. Its detection generally requires special staining, such as Ziehl-Neelsen staining. We experienced three cases in which tuberculosis was first suggested by Gram staining of sputum or pus, confirmed by Ziehl-Neelsen staining, and diagnosed by polymerase chain reaction or culture. To find colorless tubercle bacilli in clinical samples with various organisms, varying the focus to slightly longer and shorter during study of the slides is indispensable. We present criteria for detecting infective pulmonary tuberculosis in Gram staining. First, in the ordinary focus, weakly stained, thin, gram-positive bacilli are found; second, with a slightly longer focus distance, the thin, cord-like, conspicuous gram-positive bacilli can be observed; and third, with a shorter focus distance, the gram-positive bacilli have changed into the brightened, colorless, or ghost ones. Four laboratory technologists each evaluated 20 Gram-stained samples after being lectured on the criteria, with no prior information about the sample. They accurately evaluated the presence of the bacilli in Gram-stained preparations in more than 90% of samples containing 3+ bacilli on Ziehl-Neelsen staining. Gram staining is available as an easy and rapid initial clue to recognize highly infective tuberculosis.

  7. Mezclas de alfalfa y gramíneas en la serie sabana de bogotá tipo franco arcilloso.

    OpenAIRE

    Chaverra Gil., Hernán

    2012-01-01

    En el Centro Nacional de Investigaciones Agrícolas, Tibaitatá, y en la serie de suelos Sabana de Bogotá, tipo frnaco arcilloso, se llevaron a cabo dos experimentos con mezclas de alfalfa y gramíneas. En el primer ensayo, se sembraron simultáneamente con la alfalfa, ryegrass inglés, rygrass anual y orchoso. Los métodos de siembra utilizados fueron: a) alfalfa y gramíneas sembradas al voleo, b) alfalfa y gramíneas en el mismo surco, c) alfalfa y gramíneas en surcos alternos, d) alfalfa en ...

  8. In vitro antimicrobial efficiency of a mouthwash containing triclosan/gantrez and sodium bicarbonate Eficiência antimicrobiana in vitro de um enxaguatório bucal contendo triclosan/gantrez e bicarbonato de sódio

    Directory of Open Access Journals (Sweden)

    Juliana Rico Pires

    2007-12-01

    Full Text Available Several antiseptic substances have been used as adjuncts to routine mechanical procedures of oral hygiene, based on their antimicrobial effects. The objective of this study was to assess in vitro the antimicrobial efficiency of a mouthwash containing Triclosan/Gantrez and sodium bicarbonate in comparison to both positive and negative controls. Standard strain samples of Escherichia coli, Pseudomonas aeruginosa, Actinomyces viscosus and Bacillus subtilis were used. Samples of Streptococcus mutans and Gram-negative bacilli were collected from 20 volunteers (10 with a clinically healthy periodontium and 10 presenting biofilm-associated gingivitis. Evaluation of the antimicrobial activity was performed by determining the minimal inhibitory concentration (MIC. The results indicated that the test solution inhibited the growth of both Gram-negative and Gram-positive microorganisms from the volunteers’ saliva as well as that of the standard strains at the MIC dilution of 1:20, whereas the MIC dilution of 0.12% chlorhexidine against the same bacteria was 1:80. Thus, even though the tested mouthrinse solution presented an in-vitro antimicrobial activity superior to that of a placebo, it was inferior to that of chlorhexidine.Diversas substâncias antisépticas têm sido utilizadas como adjuntos aos procedimentos mecânicos rotineiros de higiene oral, com base em seus efeitos antimicrobianos. O objetivo deste estudo foi avaliar, in vitro, a eficiência antimicrobiana de um enxaguatório bucal contendo Triclosan/Gantrez e bicarbonato de sódio, em comparação a controles positivos e negativos. Linhagens padrão de Escherichia coli, Pseudomonas aeruginosa, Actinomyces viscosus e Bacillus subtilis foram utilizadas. Amostras de Streptococcus mutans e Bacilos Gram-negativos foram coletadas de 20 voluntários (10 com um periodonto clinicamente saudável e 10 com gengivite associada à presença de biofilme. A avaliação da atividade antimicrobiana foi

  9. The effect of mutagens on M1 population of black gram ( Vigno ...

    African Journals Online (AJOL)

    This study was carried out with black gram (urdbean) variety TNAUCo(Bg)6 to determine the effects of gamma rays (150, 200, 250, 300 and 350 Gy) and ethyl methane sulphonate (10, 15, 20, 25, 30 mM). Data collected were on seed germination and survival, pollen and seed fertility, plant height, number of primary ...

  10. Increasing production of proteins in gram-positive microorganisms using SecG

    NARCIS (Netherlands)

    Quax, Wilhelmus J.; Caldwell, Robert M

    2003-01-01

    The present invention relates to secretion in Gram-positive microorganisms. The present invention provides the nuclei acid and amino acid sequences for the Bacillus subtilis secretion factor SecG. The present invention also provides means for increasing the secretion of heterologous or homologous

  11. EDA-gram: designing electrodermal activity fingerprints for visualization and feature extraction.

    Science.gov (United States)

    Chaspari, Theodora; Tsiartas, Andreas; Stein Duker, Leah I; Cermak, Sharon A; Narayanan, Shrikanth S

    2016-08-01

    Wearable technology permeates every aspect of our daily life increasing the need of reliable and interpretable models for processing the large amount of biomedical data. We propose the EDA-Gram, a multidimensional fingerprint of the electrodermal activity (EDA) signal, inspired by the widely-used notion of spectrogram. The EDA-Gram is based on the sparse decomposition of EDA from a knowledge-driven set of dictionary atoms. The time axis reflects the analysis frames, the spectral dimension depicts the width of selected dictionary atoms, while intensity values are computed from the atom coefficients. In this way, EDA-Gram incorporates the amplitude and shape of Skin Conductance Responses (SCR), which comprise an essential part of the signal. EDA-Gram is further used as a foundation for signal-specific feature design. Our results indicate that the proposed representation can accentuate fine-grain signal fluctuations, which might not always be apparent through simple visual inspection. Statistical analysis and classification/regression experiments further suggest that the derived features can differentiate between multiple arousal levels and stress-eliciting environments for two datasets.

  12. Performance of Gram staining on blood cultures flagged negative by an automated blood culture system.

    Science.gov (United States)

    Peretz, A; Isakovich, N; Pastukh, N; Koifman, A; Glyatman, T; Brodsky, D

    2015-08-01

    Blood is one of the most important specimens sent to a microbiology laboratory for culture. Most blood cultures are incubated for 5-7 days, except in cases where there is a suspicion of infection caused by microorganisms that proliferate slowly, or infections expressed by a small number of bacteria in the bloodstream. Therefore, at the end of incubation, misidentification of positive cultures and false-negative results are a real possibility. The aim of this work was to perform a confirmation by Gram staining of the lack of any microorganisms in blood cultures that were identified as negative by the BACTEC™ FX system at the end of incubation. All bottles defined as negative by the BACTEC FX system were Gram-stained using an automatic device and inoculated on solid growth media. In our work, 15 cultures that were defined as negative by the BACTEC FX system at the end of the incubation were found to contain microorganisms when Gram-stained. The main characteristic of most bacteria and fungi growing in the culture bottles that were defined as negative was slow growth. This finding raises a problematic issue concerning the need to perform Gram staining of all blood cultures, which could overload the routine laboratory work, especially laboratories serving large medical centers and receiving a large number of blood cultures.

  13. Pyridone Methylsulfone Hydroxamate LpxC Inhibitors for the Treatment of Serious Gram-Negative Infections

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, Justin I.; Brown, Matthew F.; Reilly, Usa; Price, Loren M.; Abramite, Joseph A.; Arcari, Joel; Barham, Rose; Che, Ye; Chen, Jinshan Michael; Chung, Seung Won; Collantes, Elizabeth M.; Desbonnet, Charlene; Doroski, Matthew; Doty, Jonathan; Engtrakul, Juntyma J.; Harris, Thomas M.; Huband, Michael; Knafels, John D.; Leach, Karen L.; Liu, Shenping; Marfat, Anthony; McAllister, Laura; McElroy, Eric; Menard, Carol A.; Mitton-Fry, Mark; Mullins, Lisa; Noe, Mark C.; O’Donnell, John; Oliver, Robert; Penzien, Joseph; Plummer, Mark; Shanmugasundaram, Veerabahu; Thoma, Christy; Tomaras, Andrew P.; Uccello, Daniel P.; Vaz, Alfin; Wishka, Donn G. (Pfizer)

    2012-11-09

    The synthesis and biological activity of a new series of LpxC inhibitors represented by pyridone methylsulfone hydroxamate 2a is presented. Members of this series have improved solubility and free fraction when compared to compounds in the previously described biphenyl methylsulfone hydroxamate series, and they maintain superior Gram-negative antibacterial activity to comparator agents.

  14. Melting point gram-atomic volumes and enthalpies of atomization for liquid elements

    International Nuclear Information System (INIS)

    Lamoreaux, R.H.

    1976-01-01

    Values of the gram-atomic volumes and enthalpies of atomization to the monatomic ideal gas state for liquid elements at their melting points are collected to facilitate predictions of the behavior of mixed systems. Estimated values are given for experimentally undetermined quantities

  15. Nodulation studies with induced mutants of black gram (Vigna mungo L.)

    International Nuclear Information System (INIS)

    Mahna, S.K.; Garg, Rekha; Parvateesam, M.

    1990-01-01

    Mutation breeding has been widely used to generate genetic variability in plants, but reports of mutations affecting the root system are less common. In the present work, black gram (Vigna mungo L. var T9), has been used for studies on the effect of induced mutations on nodulation patterns

  16. In vitro susceptibility of gram-negative bacterial isolates to chlorhexidine gluconate.

    Science.gov (United States)

    Mengistu, Y; Erge, W; Bellete, B

    1999-05-01

    To investigate the susceptibility of clinical isolates of gram-negative bacteria to chlorhexidine gluconate. Prospective laboratory study. Tikur Anbessa Hospital, Addis Ababa, Ethiopia. Clinical specimens from 443 hospital patients. Significant number of gram negative bacteria were not inhibited by chlorhexidine gluconate (0.02-0.05%) used for antisepsis. Four hundred and forty three strains of gram-negative bacteria were isolated from Tikur Anbessa Hospital patients. Escherichia coli (31.6%) and Klebsiella pneumoniae (23%) were the most frequently isolated bacteria followed by Proteus species (13.3%), Pseudomonas species (9.2%), and Citrobacter species (6.1%). Each organism was tested to chlorhexidine gluconate (CHG), minimum inhibitory concentration (MIC) ranging from 0.0001% to 1%w/v. All Salmonella species and E. coli were inhibited by CHG, MIC or = 0.1%). Our results showed that a significant number of the gram-negative bacterial isolates were not inhibited by CHG at the concentration used for disinfection of wounds or instruments (MIC 0.02-0.05% w/v). It is therefore important to select appropriate concentration of this disinfectant and rationally use it for disinfection and hospital hygiene. Continuing follow up and surveillance is also needed to detect resistant bacteria to chlorhexidine or other disinfectants in time.

  17. Novel surface display system for proteins on non-genetically modified gram-positive bacteria

    NARCIS (Netherlands)

    Bosma, T; Kanninga, R; Neef, J; Audouy, SAL; van Roosmalen, ML; Steen, A; Buist, G; Kok, J; Kuipers, OP; Robillard, G; Leenhouts, K

    A novel display system is described that allows highly efficient immobilization of heterologous proteins on bacterial surfaces in applications for which the use of genetically modified bacteria is less desirable. This system is based on nonliving and non-genetically modified gram-positive bacterial

  18. Non-oral gram-negative facultative rods in chronic periodontitis microbiota

    NARCIS (Netherlands)

    van Winkelhoff, Arie J; Rurenga, Patrick; Wekema-Mulder, Gepke J; Singadji, Zadnach; Rams, Thomas E

    OBJECTIVE: The subgingival prevalence of gram-negative facultative rods not usually inhabiting or indigenous to the oral cavity (non-oral GNFR), as well as selected periodontal bacterial pathogens, were evaluated by culture in untreated and treated chronic periodontitis patients. METHODS:

  19. Growth, nodulation and yield of black gram [ Vigna mungo (L.) Hepper

    African Journals Online (AJOL)

    The present study was undertaken to investigate the effect of EM application and two strains of nitrogen fixing Bradyrhizobium japonicum (TAL- 102 and MN-S) on plant growth, nodulation and yield of black gram [Vigna mungo (L.) Hepper] in different soil amendment systems including unamended soil, farmyard manure ...

  20. Nanotransformation of Vancomycin Overcomes the Intrinsic Resistance of Gram-Negative Bacteria.

    Science.gov (United States)

    Fernandes, Margarida M; Ivanova, Kristina; Hoyo, Javier; Pérez-Rafael, Sílvia; Francesko, Antonio; Tzanov, Tzanko

    2017-05-03

    The increased emergence of antibiotic-resistant bacteria is a growing public health concern, and although new drugs are constantly being sought, the pace of development is slow compared with the evolution and spread of multidrug-resistant species. In this study, we developed a novel broad-spectrum antimicrobial agent by simply transforming vancomycin into nanoform using sonochemistry. Vancomycin is a glycopeptide antibiotic largely used for the treatment of infections caused by Gram-positive bacteria but inefficient against Gram-negative species. The nanospherization extended its effect toward Gram-negative Escherichia coli and Pseudomonas aeruginosa, making these bacteria up to 10 and 100 times more sensitive to the antibiotic, respectively. The spheres were able to disrupt the outer membranes of these bacteria, overcoming their intrinsic resistance toward glycopeptides. The penetration of nanospheres into a Langmuir monolayer of bacterial membrane phospholipids confirmed the interaction of the nanoantibiotic with the membrane of E. coli cells, affecting their physical integrity, as further visualized by scanning electron microscopy. Such mechanism of antibacterial action is unlikely to induce mutations in the evolutionary conserved bacterial membrane, therefore reducing the possibility of acquiring resistance. Our results indicated that the nanotransformation of vancomycin could overcome the inherent resistance of Gram-negative bacteria toward this antibiotic and disrupt mature biofilms at antibacterial-effective concentrations.

  1. The effect of mutagens on M1 population of black gram (Vigno ...

    African Journals Online (AJOL)

    Ramya

    2014-02-19

    Feb 19, 2014 ... This study was carried out with black gram (urdbean) variety TNAUCo(Bg)6 to determine the effects of gamma rays (150, 200, 250, 300 and 350 Gy) and ethyl methane sulphonate (10, 15, 20, 25, 30 mM). Data collected were on seed germination and survival, pollen and seed fertility, plant height, number of.

  2. Anton Grams dem Gustav Friedrich Wilhelm Großmann: Mozart schreibe eine neue Oper

    Czech Academy of Sciences Publication Activity Database

    Jonášová, Milada

    2016-01-01

    Roč. 53, č. 1 (2016), s. 29-53 ISSN 0018-7003 R&D Projects: GA ČR GAP409/12/2563 Institutional support: RVO:68378076 Keywords : Mozart * 1786 * letter * Anton Grams * Gustav Friedrich Wilhelm Großmann Subject RIV: AL - Art, Architecture, Cultural Heritage

  3. The impact of foliar boron sprays on reproductive biology and seed quality of black gram.

    Science.gov (United States)

    Pandey, Nalini; Gupta, Bhavana

    2013-01-01

    An experiment was conducted under glass house condition to study the effect of foliar application of boron (B) on reproductive biology and seed quality of black gram (Vigna mungo). Black gram (V. mungo L. var. DPU-88-31) was grown under controlled sand culture condition at deficient and sufficient B levels. After 32 days of sowing B deficient plants were sprayed with three concentrations of B (0.05%, 0.1% and 0.2% borax) at three different stages of reproductive development, i.e. prior to flowering, initiation of bud formation and after bud formation. Deficient B supply decreased the anther and pollen size, pollen tube growth, pollen viability as well as stigmatic receptivity which were increased by foliar B application. Foliar spray at all the three concentrations and at all stages increased the yield parameters like number of pods, pod size and number of seeds formed per plant. Foliar B application also improved the seed yield and seed quality in terms of storage seed proteins (albumin, globulin, glutenin and prolamin) and carbohydrates (sugars and starch) in black gram. The foliar application of B in appropriate doses (particularly 0.1%) after bud formation made quantitative and qualitative improvement in seed yield of black gram by supplementing additional/critical B requirements for reproductive development. Copyright © 2012 Elsevier GmbH. All rights reserved.

  4. Clinical outcomes and safety of colistin in treatment of gram negative infections: A prospective observational study

    Directory of Open Access Journals (Sweden)

    Kinnari Desai

    2016-08-01

    Conclusion: Colistin is effective in treatment of gram negative infections and its use should be reappraised. However since colistin is the last resort it is imperative to make its best use to ensure that it remains as a safe and effective mode of treatment when need be.

  5. Mars Global Reference Atmospheric Model 2001 Version (Mars-GRAM 2001): Users Guide

    Science.gov (United States)

    Justus, C. G.; Johnson, D. L.

    2001-01-01

    This document presents Mars Global Reference Atmospheric Model 2001 Version (Mars-GRAM 2001) and its new features. As with the previous version (mars-2000), all parameterizations fro temperature, pressure, density, and winds versus height, latitude, longitude, time of day, and season (Ls) use input data tables from NASA Ames Mars General Circulation Model (MGCM) for the surface through 80-km altitude and the University of Arizona Mars Thermospheric General Circulation Model (MTGCM) for 80 to 70 km. Mars-GRAM 2001 is based on topography from the Mars Orbiter Laser Altimeter (MOLA) and includes new MGCM data at the topographic surface. A new auxiliary program allows Mars-GRAM output to be used to compute shortwave (solar) and longwave (thermal) radiation at the surface and top of atmosphere. This memorandum includes instructions on obtaining Mars-GRAN source code and data files and for running the program. It also provides sample input and output and an example for incorporating Mars-GRAM as an atmospheric subroutine in a trajectory code.

  6. Improved annotation of conjugated bile acid hydrolase superfamily members in Gram-positive bacteria.

    NARCIS (Netherlands)

    Lambert, J.M.; Siezen, R.J.; Vos, W.M. de; Kleerebezem, M.

    2008-01-01

    Most Gram-positive bacteria inhabiting the gastrointestinal tract are capable of hydrolysing bile salts. Bile salt hydrolysis is thought to play an important role in various biological processes in the host. Therefore, correct annotation of bacterial bile salt hydrolases (Bsh) in public databases

  7. Caractérisation phénotypique des bacilles à gram négatif ...

    African Journals Online (AJOL)

    From March to June 2013, all strains of Gram-negative bacilli resistant to at least a third generation cephalosporin for Enterobacteriaceae, or to ceftazidim (for Pseudomonas spp) and/or to carbapenem for all species, were consecutively included in the study. For each strain, susceptibility to a large panel of antibiotics by the ...

  8. Tribolium castaneum defensins are primarily active against Gram-positive bacteria

    Czech Academy of Sciences Publication Activity Database

    Tonk, M.; Knorr, E.; Cabezas-Cruz, A.; Valdés, James J.; Kollewe, C.; Vilcinskas, A.

    2015-01-01

    Roč. 132, NOV 2015 (2015), s. 208-215 ISSN 0022-2011 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Antimicrobial peptides * Defensin * Innate immunity * Insects * Tribolium castaneum * Gram-positive bacteria Subject RIV: EI - Biotechnology ; Bionics Impact factor: 2.198, year: 2015

  9. Activation of toll-like receptors 2 and 4 by gram-negative periodontal bacteria

    NARCIS (Netherlands)

    Kikkert, R.; Laine, M. L.; Aarden, L. A.; van Winkelhoff, A. J.

    2007-01-01

    BACKGROUND/AIMS: Periodontitis is a chronic infectious disease associated with a gram-negative subgingival microflora. Bacterial components stimulate, among other receptors, Toll-like receptor (TLR) 2 and/or TLR4. Accumulating evidence indicates that both qualitatively and quantitatively distinct

  10. Loss of outer membrane integrity in Gram-negative bacteria by silver ...

    Indian Academy of Sciences (India)

    Mater. Sci., Vol. 39, No. 7, December 2016, pp. 1871–1878. c Indian Academy of Sciences. DOI 10.1007/s12034-016-1317-5. Loss of outer membrane integrity in Gram-negative bacteria by silver nanoparticles loaded with Camellia sinensis leaf phytochemicals: plausible mechanism of bacterial cell disintegration. M SINGH.

  11. Prevalence of AmpC β-lactamase among Gram-negative bacteria ...

    African Journals Online (AJOL)

    Purpose: Infections caused by AmpC-positive bacteria results in high patient morbidity and mortality making their detection clinically important as they cannot be detected in routine susceptibility testing. This study aim to determine the prevalence of AmpC β-lactamase among Gram negative bacteria recovered from clinical ...

  12. An increasing proportion of infants weight more than 4000 grams at birth

    DEFF Research Database (Denmark)

    Ørskou, J.; Kesmodel, Ulrik; Henriksen, Tine Brink

    2001-01-01

    Background. To investigate how mean birthweight has changed in the past decade, and to describe changes in the proportion of infants with a birthweight above 4000 grams (g). Methods. We analyzed data on 43,561 singleton infants born between 1990 and 1999 at Aarhus University Hospital, Denmark...

  13. Neonatal survival of infants less than 2000 grams born at Kenyatta ...

    African Journals Online (AJOL)

    Objective: To determine the birthweight specific neonatal survival of infants born weighing less than 2000 grams at Kenyatta National Hospital. Design: A cross sectional survey. Setting: Newborn Unit, Kenyatta National Hospital, Nairobi. Main outcome measures: The proportion of infants surviving the first 28 days of life ...

  14. Dry and moist heat sterilisation cannot inactivate pyrogenicity of Gram positive microorganisms

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, Erik W; Christensen, Jens D

    2005-01-01

    In the monocytic cell line Mono Mac 6 pyrogens induce interleukin-6 secretion dose dependently. The aim of this study is to examine the interleukin-6 inducing capacity of Gram positive Staphylococcus aureus and Bacillus subtilis endospores after moist and dry heat sterilisation. Moist heat...

  15. The structures of lipopolysaccharides from plant-associated gram-negative bacteria

    DEFF Research Database (Denmark)

    Molinaro, Antonio; Newman, Mari-Anne; Lanzetta, Rosa

    2009-01-01

    Gram-negative bacterial lipopolysaccharides (LPSs) have multiple roles in plant-microbe interactions. LPSs contribute to the low permeabilities of bacterial outer membranes, which act as barriers to protect bacteria from plant-derived antimicrobial substances. Conversely, perception of LPSs by pl...

  16. Serum procalcitonin elevation in critically ill patients at the onset of bacteremia caused by either gram negative or gram positive bacteria

    Directory of Open Access Journals (Sweden)

    Prin Sébastien

    2008-03-01

    Full Text Available Abstract Background In the ICU, bacteremia is a life-threatening infection whose prognosis is highly dependent on early recognition and treatment with appropriate antibiotics. Procalcitonin levels have been shown to distinguish between bacteremia and noninfectious inflammatory states accurately and quickly in critically ill patients. However, we still do not know to what extent the magnitude of PCT elevation at the onset of bacteremia varies according to the Gram stain result. Methods Review of the medical records of every patient treated between May, 2004 and December, 2006 who had bacteremia caused by either Gram positive (GP or Gram negative (GN bacteria, and whose PCT dosage at the onset of infection was available. Results 97 episodes of either GN bacteremia (n = 52 or GP bacteremia (n = 45 were included. Procalcitonin levels were found to be markedly higher in patients with GN bacteremia than in those with GP bacteremia, whereas the SOFA score value in the two groups was similar. Moreover, in the study population, a high PCT value was found to be independently associated with GN bacteremia. A PCT level of 16.0 ng/mL yielded an 83.0% positive predictive value and a 74.0% negative predictive value for GN-related bacteremia in the study cohort (AUROCC = 0.79; 95% CI, 0.71–0.88. Conclusion In a critically ill patient with clinical sepsis, GN bacteremia could be associated with higher PCT values than those found in GP bacteremia, regardless of the severity of the disease.

  17. [Characteristics of epidemiology and antimicrobial resistance of gram-negative bacterial bloodstream infections in children].

    Science.gov (United States)

    Dong, L; Zhang, X Y; Li, C C; Li, Z; Xia, Y Q

    2017-09-02

    Objective: To study the epidemiology and antimicrobial resistance of Gram-negative bacterial bloodstream infections in children, and to guide the choice of antimicrobials and the control of nosocomial infection. Method: Clinical data, bacteriology and antimicrobial susceptibility test results were collected retrospectively in hospitalized children who were diagnosed with gram-negative bacterial bloodstream infections in Yuying Children's Hospital of Wenzhou Medical University from January, 2010 to December, 2015. Result: A total of 399 cases (253 male and 146 female) were identified. The age ranged from 16 hours to 16 years (median age 10.1 months). The majority of cases were collected from division of neonatology ( n =261, 65.4%), followed by 31 cases (7.8%) from pediatric intensive care unit and 29 cases (7.3%) from Gastroenterology Department; 275 cases (68.9%) had underlying diseases, mainly including preterm birth( n =172), neonatal respiratory distress syndrome( n =67) and newborn asphyxia( n =53). Eighty cases had received invasive procedures and 20 had surgical operation; 149 cases (37.3%) were community-acquired and 250 cases (62.7%) were hospital acquired. Fifty cases had complications, among those, 40 cases had septic shock, 32 cases had multiple organ dysfunction syndrome and 7 cases had disseminated intravascular coagulation; 288 cases were cured, 48 improved, 17 gave up treatment and discharged, and 46 died; totally 408 strains were isolated from 399 children, including Enterobacteriaceae (346, 84.8%), non-fermentative Gram-negative bacteria (49, 12.0%) and other gram-negative bacteria (13, 3.2%). The resistance rates of Escherichia coli ( n =175) and Klebsiella pneumoniae ( n =106) to carbapenems, β-lactams enzyme and its inhibitors, amikacin and cefoxitin were all lower than 10%. Totally 245 multi-drug resistant strains (60.1%) were isolated, including 225 strains of Enterobacteriaceae and 18 strains of non-fermentative Gram-negative bacteria ( P

  18. N-gram analysis of 970 microbial organisms reveals presence of biological language models

    Directory of Open Access Journals (Sweden)

    Ganapathiraju Madhavi K

    2011-01-01

    Full Text Available Abstract Background It has been suggested previously that genome and proteome sequences show characteristics typical of natural-language texts such as "signature-style" word usage indicative of authors or topics, and that the algorithms originally developed for natural language processing may therefore be applied to genome sequences to draw biologically relevant conclusions. Following this approach of 'biological language modeling', statistical n-gram analysis has been applied for comparative analysis of whole proteome sequences of 44 organisms. It has been shown that a few particular amino acid n-grams are found in abundance in one organism but occurring very rarely in other organisms, thereby serving as genome signatures. At that time proteomes of only 44 organisms were available, thereby limiting the generalization of this hypothesis. Today nearly 1,000 genome sequences and corresponding translated sequences are available, making it feasible to test the existence of biological language models over the evolutionary tree. Results We studied whole proteome sequences of 970 microbial organisms using n-gram frequencies and cross-perplexity employing the Biological Language Modeling Toolkit and Patternix Revelio toolkit. Genus-specific signatures were observed even in a simple unigram distribution. By taking statistical n-gram model of one organism as reference and computing cross-perplexity of all other microbial proteomes with it, cross-perplexity was found to be predictive of branch distance of the phylogenetic tree. For example, a 4-gram model from proteome of Shigellae flexneri 2a, which belongs to the Gammaproteobacteria class showed a self-perplexity of 15.34 while the cross-perplexity of other organisms was in the range of 15.59 to 29.5 and was proportional to their branching distance in the evolutionary tree from S. flexneri. The organisms of this genus, which happen to be pathotypes of E.coli, also have the closest perplexity values with

  19. Negative mood states and related factors in a sample of adolescent secondary-school students in Barcelona (Spain Estados de ánimo negativos y los factores relacionados en una muestra de adolescentes de enseñanza secundaria de Barcelona

    Directory of Open Access Journals (Sweden)

    Emily Q. Ahonen

    2007-02-01

    Full Text Available Introduction: Poor mental health is a common problem in adolescence. Little information is available, however, about the factors influencing negative mood states in otherwise healthy adolescents. We aimed to describe the mood states and related factors in a sample of adolescents in the city of Barcelona (Spain. Methods: We administered a health survey to a sample of 2,727 students from public, subsidized, and private schools in Barcelona, aged approximately 14, 16, and 18 years old. To analyze the associations among moods and related factors, we used bivariate logistic regression, and fitted multivariate logistic regressions using the statistically significant variables from the bivariate analysis. To examine the possible group effects of the school on individual students, we employed multilevel analysis. Results: The frequencies of negative mood states increased with age, with girls consistently reporting more frequent negative mood states than boys. The factors associated with negative mood states were problematic alcohol use, perceived mistreatment or abuse, antisocial behavior, intention to use or current use of illegal drugs (not including cannabis, lower perceived academic performance, and feeling isolated. Conclusions: Mood states are influenced by lifestyle and social factors, about which there is little local information. To plan and implement appropriate public health interventions, more complete information about the possible areas of influence is required. To complement the information obtained from studies such as the present study, longitudinal and qualitative studies would be desirable.Introducción: El deterioro de la salud mental es un problema frecuente en la adolescencia. Sin embargo, se sabe poco de los factores influyentes en los estados de ánimo negativos en adolescentes saludables. Pretendemos describir los estados de ánimo negativos y los factores relacionados en una muestra de adolescentes de la ciudad de Barcelona. M

  20. Formigas como veiculadoras de microrganismos em ambiente hospitalar Ants as carriers of microorganisms in hospital environments

    Directory of Open Access Journals (Sweden)

    Rogério dos Santos Pereira

    2008-10-01

    Full Text Available Existe preocupação sobre as reais possibilidades de agravos à saúde pública que possam ser causados pela veiculação de agentes patogênicos através de formigas urbanas. O presente trabalho teve por objetivo isolar e identificar os microrganismos associados às formigas em ambiente hospitalar. Foram coletadas 125 formigas, da mesma espécie, em diferentes unidades de um Hospital Universitário. Cada formiga foi coletada com swab embebido em solução fisiológica e transferida para um tubo com caldo Brain Heart Infusion e incubados 35ºC por 24 horas. A partir de cada tubo, com crescimento, foram realizadas inoculações, em meios específicos, para isolamento dos microrganismos. As formigas apresentaram alta capacidade de veiculação de grupos de microrganismos, sendo que 63,5% das cepas eram bacilos Gram positivos produtores de esporos, 6,3% eram bacilos Gram negativos, cocos Gram positivos corresponderam a 23,1% das cepas, 6,7% eram fungos filamentosos e 0,5% eram leveduras. Desta forma, pode-se inferir que as formigas podem ser um dos responsáveis pela disseminação de microrganismos em ambientes hospitalares.Concern exists regarding the real possibility of public health threats caused by pathogenic agents that are carried by urban ants. The present study had the objective of isolating and identifying the microorganisms that are associated with ants in hospital environments. One hundred and twenty-five ants of the same species were collected from different units of a university hospital. Each ant was collected using a swab soaked with physiological solution and was transferred to a tube containing brain heart infusion broth and incubated at 35ºC for 24 hours. From each tube, with growth, inoculations were made into specific culturing media, to isolate any microorganisms. The ants presented a high capacity for carrying microorganism groups: spore-producing Gram-positive bacilli 63.5%, Gram-negative bacilli 6.3%, Gram-positive cocci

  1. Effectiveness of oral antibiotics for definitive therapy of Gram-negative bloodstream infections.

    Science.gov (United States)

    Kutob, Leila F; Justo, Julie Ann; Bookstaver, P Brandon; Kohn, Joseph; Albrecht, Helmut; Al-Hasan, Majdi N

    2016-11-01

    There is paucity of data evaluating intravenous-to-oral antibiotic switch options for Gram-negative bloodstream infections (BSIs). This retrospective cohort study examined the effectiveness of oral antibiotics for definitive treatment of Gram-negative BSI. Patients with Gram-negative BSI hospitalised for antibiotics were included in this study. The cohort was stratified into three groups based on bioavailability of oral antibiotics prescribed (high, ≥95%; moderate, 75-94%; and low, antibiotics were prescribed to 106, 179 and 77 patients, respectively, for definitive therapy of Gram-negative BSI. Mean patient age was 63 years, 217 (59.9%) were women and 254 (70.2%) had a urinary source of infection. Treatment failure rates were 2%, 12% and 14% in patients receiving oral antibiotics with high, moderate and low bioavailability, respectively (P = 0.02). Risk of treatment failure in the multivariate Cox model was higher in patients receiving antibiotics with moderate [adjusted hazard ratio (aHR) = 5.9, 95% CI 1.6-38.5; P = 0.005] and low bioavailability (aHR = 7.7, 95% CI 1.9-51.5; P = 0.003) compared with those receiving oral antimicrobial agents with high bioavailability. These data demonstrate the effectiveness of oral antibiotics with high bioavailability for definitive therapy of Gram-negative BSI. Risk of treatment failure increases as bioavailability of the oral regimen declines. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  2. Relationship between Gram negative enteric rods, Aggregatibacter actinomycetemcomitans, and clinical parameters in periodontal disease

    Directory of Open Access Journals (Sweden)

    Carlos M Ardila

    2012-01-01

    Full Text Available Background: The association between Gram negative enteric rods and Aggregatibacter actinomycetemcomitans in periodontal diseases has received little attention in the literature. The objective of this study was to explore the relationship between these organisms and clinical parameters of periodontal disease. Materials and Methods: Clinical parameters and occurrence of Gram-negative enteric rods and A. actinomycetemcomitans were examined in 76 patients with chronic periodontitis. Chi-square and Mann-Whitney tests were used to determine differences in clinical variables versus the presence or absence of both microorganisms. Correlation among both organisms and clinical data were determined using Spearman rank correlation coefficient. Results: Gram-negative enteric rods and A. actinomycetemcomitans were detected in 20 (26.3% and 18 (23.7% individuals, respectively. A total of 14 (18.4% patients harbored both microorganisms studied. There were significantly positive correlations between enteric rods and presence of A. actinomycetemcomitans (r=0.652, P<0.0001. Both microorganisms were significant and positively correlated with probing depth (PD, clinical attachment level, and bleeding on probing (P<0.0001. The mean PD (mm of the sampled sites was significantly deeper in patients with presence of A. actinomycetemcomitans and Gram-negative enteric rods. Conclusion: The results of the present study suggest a strong positive correlation between Gram-negative enteric rods and A. actinomycetemcomitans in the population studied. This finding must be taken into account when considering the best therapeutic approach, including the utilization of antimicrobials. The adverse clinical outcomes observed in presence of these microorganisms could have implications in the pathogenesis of periodontal disease and a possible impact on outcomes after treatment.

  3. Microcins from Enterobacteria: On the Edge Between Gram-Positive Bacteriocins and Colicins

    Science.gov (United States)

    Rebuffat, Sylvie

    Most bacteria and archaea produce gene-encoded antimicrobial peptides/proteins called bacteriocins, which are secreted by the producing bacteria to compete against other microorganisms in a given niche. They are considered important mediators of intra- and interspecies interactions and therefore a factor in ­maintaining the microbial diversity and stability. They are ribosomally synthesized, and most of them are produced as inactive precursor proteins, which in some cases are further enzymatically modified. Bacteriocins generally exert potent antibacterial activities directed against bacterial species closely related to the producing bacteria. Bacteriocins are abundant and diverse in Gram-negative and Gram-positive bacteria. This chapter focuses on colicins and microcins from enterobacteria (mainly Escherichia coli) and on bacteriocins from lactic acid bacteria (LAB). Microcins are the lower-molecular-mass bacteriocins produced by Gram-negative bacteria with a repertoire of only 14 representatives. They form a very restricted family of bacteriocins, compared to the huge family of LAB bacteriocins that is constituted of several hundreds of peptides, with which microcins share common characteristics. Nevertheless, microcins also show similarities, particularly in their uptake mechanisms, with the higher-molecular-mass colicins, also produced by E. coli strains. On the edge between LAB bacteriocins and colicins, microcins appear to combine highly efficient strategies developed by both Gram-positive and Gram-negative bacteria at different levels, including uptake, translocation, killing of target cells, and immunity of the producing bacteria, making them important actors of bacterial competitions and fascinating models for novel concepts toward antimicrobial strategies and against resistance mechanisms.

  4. Características clínicas y microbiológicas de los pacientes neutropénicos febriles con neoplasias hematológicas

    Directory of Open Access Journals (Sweden)

    Fabián Alberto Jaimes Barragán

    2008-02-01

    Full Text Available Se estudiaron en forma retrospectiva 441 historias clínicas en el período comprendido entre enero de 2003 y diciembre de 2005. De éstas, se identificaron las características de 117 episodios de neutropenia febril en 96 pacientes. La mediana de edad fue 34 años y el 56,4% de los episodios ocurrieron en hombres. Las más frecuentes neoplasias hematológicas relacionadas con neutropenia febril fueron leucemia linfoide aguda (LLA y leucemia mieloide aguda (LMA con 45 episodios de cada una, que corresponden al 76,9%. La mediana de duración de la neutropenia fue 8 días y el 60,7% de los casos entraron en la categoría de neutropenia grave. La mortalidad global fue del 32% y el 81,5% de estas muertes estuvieron asociadas directamente con la infección. Se obtuvo aislamiento microbiológico en el 51% de los eventos. Los bacilos gram negativos (BGN constituyeron el 59% de los aislamientos microbiológicos y los cocos gram positivos el 32%. El 14,3% de los BGN aislados fueron positivos para beta lactamasas de espectro extendido (BLEE y la resistencia global a ciprofloxacina alcanzó el 31,4%. El esquema antimicrobiano empírico más frecuentemente utilizado fue ciprofloxacina más ceftriaxona; la respuesta terapéutica fue desfavorable en 65% de los casos. En el Hospital San Vicente de Paúl de Medellín siguen primando los gérmenes gram negativos y son altas las tasas de resistencia a los antibióticos utilizados tradicionalmente como de primera línea, lo que sugiere la necesidad de reevaluar la pertinencia de estos esquemas.

  5. Microbial keratitis in the elderly: a 32-year review Ceratite infecciosa em idosos: revisão de 32 anos

    Directory of Open Access Journals (Sweden)

    Renato Magalhães Passos

    2010-08-01

    idades, 1.545 casos em idosos foram revisados. A idade média foi de 71,0 ± 7,8 anos, variando de 60 a 101 anos. Foram 707 homens (45,6% e 838 mulheres (54,3%. Os principais fatores associados foram: cirurgia ocular prévia (25,1%, trauma ocular (7,2% e uso de lentes de contato (3,0%. Bacterioscopia foi positiva em 40,5% dos casos. A positividade das culturas para qualquer agente foi de 53,5% (bactérias 47,0%, fungos 6,1%, Acanthamoeba 0,4%. As bactérias mais frequentes foram os cocos gram positivos (principalmente Staphylococcus coagulase negativo e bacilos gram negativos (principalmente Pseudomonas, Moraxella e Proteus, enquanto os fungos mais frequentes foram os filamentosos (Fusarium. CONCLUSÕES: Este estudo representa até o momento a maior série de casos de ceratite infecciosa em idosos em um centro único. O fator mais associado a esta condição em idosos foi cirurgia ocular prévia. Os agentes etiológicos mais frequentes foram as bactérias, principalmente cocos gram positivos e bacilos gram negativos.

  6. Gram Stain

    Science.gov (United States)

    ... Ulcer Pituitary Disorders Pneumonia Polycystic Ovary Syndrome Porphyria Pre-eclampsia Pregnancy Pregnancy: First Trimester (Up to 12 ... Sometimes, susceptibility testing is necessary to determine which antibiotic will be most effective in treating the infection. ...

  7. Investigation of antifouling and disinfection potential of chitosan coated iron oxide-PAN hollow fiber membrane using Gram-positive and Gram-negative bacteria.

    Science.gov (United States)

    Mukherjee, Munmun; De, Sirshendu

    2017-06-01

    Chitosan coated iron oxide nanoparticles were impregnated into polyacrylonitrile based hollow fiber membrane. The molecular weight cut off was varied in the range of 120 to 145kDa with the concentration of nanoparticles. Incorporation of nanoparticles improved the permeability, mechanical property and hydrophilicity of the membrane. The contact angle of the membrane decreased from 80° to 51° and the permeability increased by 31% at 0.5wt% nanoparticles concentration. The antibacterial and antifouling property of the membrane were investigated with two biofilm causing Gram positive and Gram negative bacteria. The damage of cell membrane was directly confirmed by release of cellular constituent absorbing in 260nm. The cellular deformation on the membrane surface was evident by direct microscopic observation in FESEM. This damage was likely caused by electrostatic interaction between NH 3 + group of nanoparticles and anionic components of phosphoryl group of bacteria. The hollow fiber membrane shows promising antibiofouling property even after long experimental run as evident by 95% flux recovery ratio. The effect of operating conditions on rejection and flux profile was investigated during long experimental run. The result indicated that there was no detectable iron in the permeate sample that could impose adverse health hazard. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Effects of Photodynamic Therapy on Gram-Positive and Gram-Negative Bacterial Biofilms by Bioluminescence Imaging and Scanning Electron Microscopic Analysis

    Science.gov (United States)

    Núñez, Silvia C.; Azambuja, Nilton; Fregnani, Eduardo R.; Rodriguez, Helena M.H.; Hamblin, Michael R.; Suzuki, Hideo; Ribeiro, Martha S.

    2013-01-01

    Abstract Objective: The aim of this study was to test photodynamic therapy (PDT) as an alternative approach to biofilm disruption on dental hard tissue, We evaluated the effect of methylene blue and a 660 nm diode laser on the viability and architecture of Gram-positive and Gram-negative bacterial biofilms. Materials and methods: Ten human teeth were inoculated with bioluminescent Pseudomonas aeruginosa or Enterococcus faecalis to form 3 day biofilms in prepared root canals. Bioluminescence imaging was used to serially quantify and evaluate the bacterial viability, and scanning electron microscopic (SEM) imaging was used to assess architecture and morphology of bacterial biofilm before and after PDT employing methylene blue and 40 mW, 660 nm diode laser light delivered into the root canal via a 300 μm fiber for 240 sec, resulting in a total energy of 9.6 J. The data were statistically analyzed with analysis of variance (ANOVA) followed by Tukey test. Results: The bacterial reduction showed a dose dependence; as the light energy increased, the bioluminescence decreased in both planktonic suspension and in biofilms. The SEM analysis showed a significant reduction of biofilm on the surface. PDT promoted disruption of the biofilm and the number of adherent bacteria was reduced. Conclusions: The photodynamic effect seems to disrupt the biofilm by acting both on bacterial cells and on the extracellular matrix. PMID:23822168

  9. 1-(2-aminophenyl)-1H-1,2,3-triazole-4-carboxylic acid: activity against Gram-positive and Gram-negative pathogens including Vibrio cholerae

    Science.gov (United States)

    Maji, Krishnendu; Haldar, Debasish

    2017-10-01

    We report a new synthetic aromatic ε-amino acid containing a triazole moiety with antimicrobial potential against Gram-positive, Gram-negative and pathogenic bacteria including Vibrio cholerae. Structure-property relationship studies revealed that all the functional groups are essential to enhance the antimicrobial activity. The 1-(2-aminophenyl)-1H-1,2,3-triazole-4-carboxylic acid was synthesized by click chemistry. From X-ray crystallography, the amino acid adopts a kink-like structure where the phenyl and triazole rings are perpendicular to each other and the amine and acid groups maintain an angle of 60°. The agar diffusion test shows that the amino acid has significant antibacterial activity. The liquid culture test exhibits that the minimum inhibitory concentration (MIC) value for Bacillus subtilis and Vibrio cholerae is 59.5 µg ml-1. FE-SEM experiments were performed to study the morphological changes of bacterial shape after treatment with compound 1. The antimicrobial activity of the amino acid was further studied by DNA binding and degradation study, protein binding, dye-binding assay and morphological analysis. Moreover, the amino acid does not have any harmful effect on eukaryotes.

  10. Efficient Photodynamic Therapy against Gram-Positive and Gram-Negative Bacteria Using THPTS, a Cationic Photosensitizer Excited by Infrared Wavelength

    Science.gov (United States)

    Schastak, Stanislaw; Ziganshyna, Svitlana; Gitter, Burkhard; Wiedemann, Peter; Claudepierre, Thomas

    2010-01-01

    The worldwide rise in the rates of antibiotic resistance of bacteria underlines the need for alternative antibacterial agents. A promising approach to kill antibiotic-resistant bacteria uses light in combination with a photosensitizer to induce a phototoxic reaction. Concentrations of 1, 10 and 100µM of tetrahydroporphyrin-tetratosylat (THPTS) and different incubation times (30, 90 and 180min) were used to measure photodynamic efficiency against two Gram-positive strains of S.aureus (MSSA and MRSA), and two Gram-negative strains of E.coli and P.aeruginosa. We found that phototoxicity of the drug is independent of the antibiotic resistance pattern when incubated in PBS for the investigated strains. Also, an incubation with 100µM THPTS followed by illumination, yielded a 6lg (≥99.999%) decrease in the viable numbers of all bacteria strains tested, indicating that the THPTS drug has a high degree of photodynamic inactivation. We then modulated incubation time, photosensitizer concentration and monitored the effect of serum on the THPTS activity. In doing so, we established the conditions to obtain the strongest bactericidal effect. Our results suggest that this new and highly pure synthetic compound should improve the efficiency of photodynamic therapy against multiresistant bacteria and has a significant potential for clinical applications in the treatment of nosocomial infections. PMID:20652031

  11. Growth of Ag-nanoparticles in an aqueous solution and their antimicrobial activities against Gram positive, Gram negative bacterial strains and Candida fungus.

    Science.gov (United States)

    Aazam, Elham Shafik; Zaheer, Zoya

    2016-04-01

    Silver nanoparticles (AgNPs) were synthesized using Ocimum sanctum (Tulsi) leaves aqueous extract as reducing as well as a capping agent in absence and presence of cetyltrimethylammonium bromide (CTAB). The resulting nanomaterials were characterized by UV-visible spectrophotometer, and transmission electron microscope. The UV-Vis spectroscopy revealed the formation of AgNPs at 400-450 nm. TEM photographs indicate that the truncated triangular silver nanoplates and/or spherical morphology of the AgNPs with an average diameter of 25 nm have been distorted markedly in presence of CTAB. The AgNPs were almost mono disperse in nature. Antimicrobial activities of AgNPs were determined by using two bacteria (Gram positive Staphylococcus aureus MTCC-3160), Gram negative Escherichia coli MTCC-450) and one species of Candida fungus (Candida albicans ATCC 90030) with Kirby-Bauer or disc diffusion method. The zone of inhibition seems extremely good showing a relatively large zone of inhibition in both Staphylococcus aureus, Escherichia coli, and Candida albicans strains.

  12. The Effect of Charge at the Surface of Silver Nanoparticles on Antimicrobial Activity against Gram-Positive and Gram-Negative Bacteria: A Preliminary Study

    International Nuclear Information System (INIS)

    Abbaszadegan, A.; Ghahramani, Y.; Nabavizadeh, M.; Gholami, A.; Hemmateenejad, I.; Dorostkar, S.; Sharghi, H.

    2014-01-01

    The bactericidal efficiency of various positively and negatively charged silver nanoparticles has been extensively evaluated in literature, but there is no report on efficacy of neutrally charged silver nanoparticles. The goal of this study is to evaluate the role of electrical charge at the surface of silver nanoparticles on antibacterial activity against a panel of microorganisms. Three different silver nanoparticles were synthesized by different methods, providing three different electrical surface charges (positive, neutral, and negative). The antibacterial activity of these nanoparticles was tested against gram-positive (i.e., Staphylococcus aureus, Streptococcus mutans, and Streptococcus pyogenes) and gram-negative (i.e., Escherichia coli and Proteus vulgaris) bacteria. Well diffusion and micro-dilution tests were used to evaluate the bactericidal activity of the nanoparticles. According to the obtained results, the positively-charged silver nanoparticles showed the highest bactericidal activity against all microorganisms tested. The negatively charged silver nanoparticles had the least and the neutral nanoparticles had intermediate antibacterial activity. The most resistant bacteria were Proteus vulgaris. We found that the surface charge of the silver nanoparticles was a significant factor affecting bactericidal activity on these surfaces. Although the positively charged nanoparticles showed the highest level of effectiveness against the organisms tested, the neutrally charged particles were also potent against most bacterial species.

  13. Comparison of methylene blue/gentian violet stain to Gram's stain for the rapid diagnosis of gonococcal urethritis in men.

    Science.gov (United States)

    Taylor, Stephanie N; DiCarlo, Richard P; Martin, David H

    2011-11-01

    We compared a simple, one-step staining procedure using a mixture of methylene blue and gentian violet to Gram stain for the detection of gonococcal urethritis. The sensitivity and specificity of both Gram stain and methylene blue/gentian violet stain were 97.3% and 99.6%, respectively. There was a 100% correlation between the 2 methods.

  14. Prior colonization is associated with increased risk of antibiotic-resistant Gram-negative bacteremia in cancer patients.

    Science.gov (United States)

    Hess, Aaron S; Kleinberg, Michael; Sorkin, John D; Netzer, Giora; Johnson, Jennifer K; Shardell, Michelle; Thom, Kerri A; Harris, Anthony D; Roghmann, Mary-Claire

    2014-05-01

    We hypothesized that prior colonization with antibiotic-resistant Gram-negative bacteria is associated with increased risk of subsequent antibiotic-resistant Gram-negative bacteremia among cancer patients. We performed a matched case-control study. Cases were cancer patients with a blood culture positive for antibiotic-resistant Gram-negative bacteria. Controls were cancer patients with a blood culture not positive for antibiotic-resistant Gram-negative bacteria. Prior colonization was defined as any antibiotic-resistant Gram-negative bacteria in surveillance or non-sterile-site cultures obtained 2-365 days before the bacteremia. Thirty-two (37%) of 86 cases and 27 (8%) of 323 matched controls were previously colonized by any antibiotic-resistant Gram-negative bacteria. Prior colonization was strongly associated with antibiotic-resistant Gram-negative bacteremia (odds ratio [OR] 7.2, 95% confidence interval [CI] 3.5-14.7) after controlling for recent treatment with piperacillin-tazobactam (OR 2.5, 95% CI 1.3-4.8). In these patients with suspected bacteremia, prior cultures may predict increased risk of antibiotic-resistant Gram-negative bacteremia. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Computing symmetrical strength of N-grams: a two pass filtering approach in automatic classification of text documents.

    Science.gov (United States)

    Agnihotri, Deepak; Verma, Kesari; Tripathi, Priyanka

    2016-01-01

    The contiguous sequences of the terms (N-grams) in the documents are symmetrically distributed among different classes. The symmetrical distribution of the N-Grams raises uncertainty in the belongings of the N-Grams towards the class. In this paper, we focused on the selection of most discriminating N-Grams by reducing the effects of symmetrical distribution. In this context, a new text feature selection method named as the symmetrical strength of the N-Grams (SSNG) is proposed using a two pass filtering based feature selection (TPF) approach. Initially, in the first pass of the TPF, the SSNG method chooses various informative N-Grams from the entire extracted N-Grams of the corpus. Subsequently, in the second pass the well-known Chi Square (χ(2)) method is being used to select few most informative N-Grams. Further, to classify the documents the two standard classifiers Multinomial Naive Bayes and Linear Support Vector Machine have been applied on the ten standard text data sets. In most of the datasets, the experimental results state the performance and success rate of SSNG method using TPF approach is superior to the state-of-the-art methods viz. Mutual Information, Information Gain, Odds Ratio, Discriminating Feature Selection and χ(2).

  16. DMPD: Gram-negative endotoxin: an extraordinary lipid with profound effects oneukaryotic signal transduction. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 1916089 Gram-negative endotoxin: an extraordinary lipid with profound effects oneuk...ep;5(12):2652-60. (.png) (.svg) (.html) (.csml) Show Gram-negative endotoxin: an extraordinary lipid with pr...tive endotoxin: an extraordinary lipid with profound effects oneukaryotic signal transduction. Authors Raetz

  17. Criticality Safety Evaluations on the Use of 200-gram Pu Mass Limit for RHWM Waste Storage Operations

    International Nuclear Information System (INIS)

    Chou, P.

    2011-01-01

    This work establishes the criticality safety technical basis to increase the fissile mass limit from 120 grams to 200 grams for Type A 55-gallon drums and their equivalents. Current RHWM fissile mass limit is 120 grams Pu for Type A 55-gallon containers and their equivalent. In order to increase the Type A 55-gallon drum limit to 200 grams, a few additional criticality safety control requirements are needed on moderators, reflectors, and array controls to ensure that the 200-gram Pu drums remain criticality safe with inadvertent criticality remains incredible. The purpose of this work is to analyze the use of 200-gram Pu drum mass limit for waste storage operations in Radioactive and Hazardous Waste Management (RHWM) Facilities. In this evaluation, the criticality safety controls associated with the 200-gram Pu drums are established for the RHWM waste storage operations. With the implementation of these criticality safety controls, the 200-gram Pu waste drum storage operations are demonstrated to be criticality safe and meet the double-contingency-principle requirement per DOE O 420.1.

  18. Rationalizing the permeation of polar antibiotics into Gram-negative bacteria

    International Nuclear Information System (INIS)

    Scorciapino, Mariano Andrea; Acosta-Gutierrez, Silvia; Benkerrou, Dehbia; D’Agostino, Tommaso; Malloci, Giuliano; Samanta, Susruta; Bodrenko, Igor; Ceccarelli, Matteo

    2017-01-01

    The increasing level of antibiotic resistance in Gram-negative bacteria, together with the lack of new potential drug scaffolds in the pipeline, make the problem of infectious diseases a global challenge for modern medicine. The main reason that Gram-negative bacteria are particularly challenging is the presence of an outer cell-protecting membrane, which is not present in Gram-positive species. Such an asymmetric bilayer is a highly effective barrier for polar molecules. Several protein systems are expressed in the outer membrane to control the internal concentration of both nutrients and noxious species, in particular: (i) water-filled channels that modulate the permeation of polar molecules and ions according to concentration gradients, and (ii) efflux pumps to actively expel toxic compounds. Thus, besides expressing specific enzymes for drugs degradation, Gram-negative bacteria can also resist by modulating the influx and efflux of antibiotics, keeping the internal concentration low. However, there are no direct and robust experimental methods capable of measuring the permeability of small molecules, thus severely limiting our knowledge of the molecular mechanisms that ultimately control the permeation of antibiotics through the outer membrane. This is the innovation gap to be filled for Gram-negative bacteria. This review is focused on the permeation of small molecules through porins, considered the main path for the entry of polar antibiotics into Gram-negative bacteria. A fundamental understanding of how these proteins are able to filter small molecules is a prerequisite to design/optimize antibacterials with improved permeation. The level of sophistication of modern molecular modeling algorithms and the advances in new computer hardware has made the simulation of such complex processes possible at the molecular level. In this work we aim to share our experience and perspectives in the context of a multidisciplinary extended collaboration within the IMI

  19. Rationalizing the permeation of polar antibiotics into Gram-negative bacteria

    Science.gov (United States)

    Scorciapino, Mariano Andrea; Acosta-Gutierrez, Silvia; Benkerrou, Dehbia; D'Agostino, Tommaso; Malloci, Giuliano; Samanta, Susruta; Bodrenko, Igor; Ceccarelli, Matteo

    2017-03-01

    The increasing level of antibiotic resistance in Gram-negative bacteria, together with the lack of new potential drug scaffolds in the pipeline, make the problem of infectious diseases a global challenge for modern medicine. The main reason that Gram-negative bacteria are particularly challenging is the presence of an outer cell-protecting membrane, which is not present in Gram-positive species. Such an asymmetric bilayer is a highly effective barrier for polar molecules. Several protein systems are expressed in the outer membrane to control the internal concentration of both nutrients and noxious species, in particular: (i) water-filled channels that modulate the permeation of polar molecules and ions according to concentration gradients, and (ii) efflux pumps to actively expel toxic compounds. Thus, besides expressing specific enzymes for drugs degradation, Gram-negative bacteria can also resist by modulating the influx and efflux of antibiotics, keeping the internal concentration low. However, there are no direct and robust experimental methods capable of measuring the permeability of small molecules, thus severely limiting our knowledge of the molecular mechanisms that ultimately control the permeation of antibiotics through the outer membrane. This is the innovation gap to be filled for Gram-negative bacteria. This review is focused on the permeation of small molecules through porins, considered the main path for the entry of polar antibiotics into Gram-negative bacteria. A fundamental understanding of how these proteins are able to filter small molecules is a prerequisite to design/optimize antibacterials with improved permeation. The level of sophistication of modern molecular modeling algorithms and the advances in new computer hardware has made the simulation of such complex processes possible at the molecular level. In this work we aim to share our experience and perspectives in the context of a multidisciplinary extended collaboration within the IMI

  20. The accuracy of Gram stain of respiratory specimens in excluding Staphylococcus aureus in ventilator-associated pneumonia.

    Science.gov (United States)

    Gottesman, Tamar; Yossepowitch, Orit; Lerner, Evgenia; Schwartz-Harari, Orna; Soroksky, Arie; Yekutieli, Daniel; Dan, Michael

    2014-10-01

    To evaluate the Gram stain of deep tracheal aspirate as a tool to direct empiric antibiotic therapy, and more specifically as a tool to exclude the need for empiric antibiotic coverage against Staphylococcus aureus in ventilator-associated pneumonia (VAP). A prospective, single-center, observational, cohort study. All wards at a community hospital. Adult patients requiring mechanical ventilation, identified as having VAP in a 54-month prospective surveillance database. Sampling of lower airway secretions by deep endotracheal aspiration was taken from each patient who developed VAP. Samples were sent immediately for Gram stain and qualitative bacterial cultures. Demographic and relevant clinical data were collected; Gram stain, culture, and antibiotic susceptibility results were documented; and outcome was followed prospectively. The analysis included 114 consecutive patients with 115 episodes of VAP from June 2007 to January 2012. Sensitivity of Gram stain compared with culture was 90.47% for gram-positive cocci, 69.6% for gram-negative rods, and 50% for sterile cultures. Specificity was 82.5%, 77.8%, and 79%, respectively. Negative predictive value was high for gram-positive cocci (97%) and sterile cultures (96%) but low for gram-negative rods (20%). Acinetobacter baumanii (45%) and Pseudomonas aeruginosa (38 %) were the prevailing isolates. S aureus was found in 18.3% of the patients. Most isolates were multiresistant. Absence of gram-positive bacteria on Gram stain had a high negative predictive value. These data can be used to narrow the initial empiric antibiotic regimen and to avoid unnecessary exposure of patients to vancomycin and other antistaphyloccocal agents. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Prevalência e fatores associados a indicadores negativos de saúde mental em adolescentes estudantes do ensino médio em Pernambuco, Brasil The prevalence of and factors associated with negative mental health indicators in adolescents attending high school in the Brazilian State of Pernambuco

    Directory of Open Access Journals (Sweden)

    Priscila Diniz de Carvalho

    2011-09-01

    Full Text Available OBJETIVOS: identificar a prevalência e fatores associados a indicadores negativos de saúde mental em adolescentes. MÉTODOS: utilizou-se um questionário previamente validado para coletar dados de 4.207 adolescentes (14-19 anos estudantes do ensino médio, selecionados através de amostragem por conglomerados em dois estágios. RESULTADOS: as prevalências de tristeza, sentimento de solidão, pensamento de suicídio, dificuldade para dormir devido à preocupação e planos de suicídio foram, respectivamente, 29,7%, 15,8%, 11,2%, 10,0% e 7,8%. A prevalência de todos os indicadores foi superior entre as moças, sendo a tristeza o indicador mais prevalente. Identificou-se que a cor da pele não foi um fator associado à ocorrência dos indicadores negativos de saúde mental, enquanto não morar com os pais apresentou associação significativa com sentimento de solidão e pensamento em suicídio. CONCLUSÕES: a prevalência de sentimento de solidão e de tristeza é alta e as moças representam um subgrupo de maior risco em relação a todos os indicadores negativos de saúde mental.OBJECTIVES: to identify the prevalence of and factors associated with negative mental health indicators among adolescents. METHODS: a previously validated questionnaire was used to gather data on 4,207 adolescents (aged between 14 and 19 years attending high school, selected by way of conglomerate sampling in two stages. RESULTS: the prevalence of sadness, feelings of loneliness, thoughts of suicide, difficulty sleeping because of anxiety, and plans to commit suicide was 29.7%, 15.8%, 11.2%, 10.0% and 7.8% respectively. The prevalence for all indicators was higher among girls, with sadness being the most prevalent indicator. It was identified that skin-color was not a factor associated with the occurrence of negative mental health indicators, while not living with parents showed a significant degree of association with feeling of loneliness and thoughts of suicide

  2. Gramática y gramáticas: entre el formalismo y el funcionalismo Grammar and grammars: between formalism and functionalism

    Directory of Open Access Journals (Sweden)

    Álvaro William Santiago Galvis

    2011-01-01

    Full Text Available En este trabajo se presentan las distintas nociones que tiene el término gramática, desde la perspectiva prescriptiva, referida al sistema organizativo de la lengua, reglas y principios que intervienen en la construcción de palabras, frases y oraciones; pasando por la no prescriptiva, de orientación científica, que estudia sistemáticamente las palabras, sus clases, posibles combinaciones, relaciones y significados que puedan atribuírseles; hasta llegar a la relacionada con los enfoques lingüísticos específicos, o cada teoría o modelo de análisis que se ha propuesto para abordar un sistema verbal. Es a partir de la inmersión en esta última acepción que se estudian los presupuestos básicos de los programas formalista y funcionalista. El primero de ellos es utilizado por la gramática como un aparato formal de descripción y explicación con el que se busca aclarar la capacidad de la mente humana para producir y comprender expresiones verbales, sin tener en cuenta factores no verbales, mientras que el segundo hace énfasis en la función comunicativa de las lenguas, de forma que la gramática queda subordinada a factores extralingüísticos.In this work the different concepts that the word grammar has are presented, from the prescriptive perspective, referred to the organizational system of the language, rules and principles involved in the construction of words, phrases and sentences; passing through non-prescriptive perspective, which has a scientific orientation that studies the words systematically, their kinds, combinations, relations and meanings that may be assigned to them; up to that related to specific linguistic approaches, or every theory or model of analysis that has been proposed to address a verbal system. It is from this latter conception that the basic assumptions of formalist and functionalist programs are. The first one as a formal unit of description and explanation in grammar which seeks to clarify the human

  3. Complexity in Animal Communication: Estimating the Size of N-Gram Structures

    Directory of Open Access Journals (Sweden)

    Reginald Smith

    2014-01-01

    Full Text Available In this paper, new techniques that allow conditional entropy to estimate the combinatorics of symbols are applied to animal communication studies to estimate the communication’s repertoire size. By using the conditional entropy estimates at multiple orders, the paper estimates the total repertoire sizes for animal communication across bottlenose dolphins, humpback whales and several species of birds for an N-gram length of one to three. In addition to discussing the impact of this method on studies of animal communication complexity, the reliability of these estimates is compared to other methods through simulation. While entropy does undercount the total repertoire size due to rare N-grams, it gives a more accurate picture of the most frequently used repertoire than just repertoire size alone.

  4. When Ribonucleases Come into Play in Pathogens: A Survey of Gram-Positive Bacteria

    Directory of Open Access Journals (Sweden)

    Brian C. Jester

    2012-01-01

    Full Text Available It is widely acknowledged that RNA stability plays critical roles in bacterial adaptation and survival in different environments like those encountered when bacteria infect a host. Bacterial ribonucleases acting alone or in concert with regulatory RNAs or RNA binding proteins are the mediators of the regulatory outcome on RNA stability. We will give a current update of what is known about ribonucleases in the model Gram-positive organism Bacillus subtilis and will describe their established roles in virulence in several Gram-positive pathogenic bacteria that are imposing major health concerns worldwide. Implications on bacterial evolution through stabilization/transfer of genetic material (phage or plasmid DNA as a result of ribonucleases' functions will be covered. The role of ribonucleases in emergence of antibiotic resistance and new concepts in drug design will additionally be discussed.

  5. Community-acquired multidrug-resistant Gram-negative bacterial infective endocarditis.

    Science.gov (United States)

    Naha, Sowjanya; Naha, Kushal; Acharya, Vasudev; Hande, H Manjunath; Vivek, G

    2014-08-05

    We describe two cases of bacterial endocarditis secondary to multidrug-resistant Gram-negative organisms. In both cases, the diagnosis was made in accordance with the modified Duke's criteria and confirmed by histopathological analysis. Furthermore, in both instances there were no identifiable sources of bacteraemia and no history of contact with hospital or other medical services prior to the onset of symptoms. The patients were managed in similar fashion with prolonged broad-spectrum antibiotic therapy and surgical intervention and made complete recoveries. These cases highlight Gram-negative organisms as potential agents for endocarditis, as well as expose the dissemination of such multidrug-resistant bacteria into the community. The application of an integrated medical and surgical approach and therapeutic dilemmas encountered in managing these cases are described. 2014 BMJ Publishing Group Ltd.

  6. Lipopolysaccharide biogenesis and transport at the outer membrane of Gram-negative bacteria.

    Science.gov (United States)

    Sperandeo, Paola; Martorana, Alessandra M; Polissi, Alessandra

    2017-11-01

    The outer membrane (OM) of Gram-negative bacteria is an asymmetric lipid bilayer containing a unique glycolipid, lipopolysaccharide (LPS) in its outer leaflet. LPS molecules confer to the OM peculiar permeability barrier properties enabling Gram-negative bacteria to exclude many toxic compounds, including clinically useful antibiotics, and to survive harsh environments. Transport of LPS poses several problems to the cells due to the amphipatic nature of this molecule. In this review we summarize the current knowledge on the LPS transport machinery, discuss the challenges associated with this process and present the solutions that bacterial cells have evolved to address the problem of LPS transport and assembly at the cell surface. Finally, we discuss how knowledge on LPS biogenesis can be translated for the development of novel antimicrobial therapies. This article is part of a Special Issue entitled: Bacterial Lipids edited by Russell E. Bishop. Copyright © 2016. Published by Elsevier B.V.

  7. Gas-containing brain abscess due to gram-positive anaerobic cocci

    International Nuclear Information System (INIS)

    Inui, Shoji; Kamada, Kitaro; Takahashi, Toku; Iwanaga, Hideaki; Honda, Makoto

    1983-01-01

    A successfully treated 19-year-old man with gas-containing brain abscess due to gram-positive anaerobic cocci is described. A CT scan disclosed a right-frontal low-density area with an enhancing rim and a perifocal low-density area. A gas shadow with a gas-fluid level was clearly seen within the cystic cavity. There was a marked improvement in the conscious level and hemiparesis immediately after the operation. On the 7th postoperative day, the patient had almost no neurological deficits. A further CT scan 80 days after the operation showed only a small low-density area at the frontal lobe. No gas-containing brain abscess due to gram-positive anaerobic cocci has been reported except this case. The immediate recognition and institution of therapy using serial CT scans for a gas-containing brain abscess results in a complete cure of the patient. (J.P.N.)

  8. Antimicrobial compounds targeting Gram-negative bacteria in food: Their mode of action and combinational effects

    DEFF Research Database (Denmark)

    Hyldgaard, Morten

    2015-01-01

    they interact with bacterial cells to exert their mechanism of inhibition or killing. Furthermore, natural antimicrobials are often not potent enough as single compounds, and may cause unwanted sensory side-effects, which limit the quantities that can be applied to food. These problems might be circumvented......Gram-negative bacteria are a major cause of food spoilage and foodborne illnesses. However, finding effective solutions against Gram-negative bacteria are complicated because of increasing consumer demands for more natural, minimally processed, and fresh high quality food products without...... that isoeugenol permeabilized the cytoplasmic membrane, and probably inhibited intracellular esterases. We proposed that isoeugenol interacted with cytoplasmic membranes of E. coli in a reversible fashion, which destabilized membranes to become leaky in a non-disruptive detergent-like mechanism. In the third...

  9. Intrinsic, adaptive and acquired antimicrobial resistance in Gram-negative bacteria.

    Science.gov (United States)

    Arzanlou, Mohsen; Chai, Wern Chern; Venter, Henrietta

    2017-02-28

    Gram-negative bacteria are responsible for a large proportion of antimicrobial-resistant infections in humans and animals. Among this class of bacteria are also some of the most successful environmental organisms. Part of this success is their adaptability to a variety of different niches, their intrinsic resistance to antimicrobial drugs and their ability to rapidly acquire resistance mechanisms. These mechanisms of resistance are not exclusive and the interplay of several mechanisms causes high levels of resistance. In this review, we explore the molecular mechanisms underlying resistance in Gram-negative organisms and how these different mechanisms enable them to survive many different stress conditions. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  10. Transmission dynamics of gram-negative bacterial pathogens in the anesthesia work area.

    Science.gov (United States)

    Loftus, Randy W; Brown, Jeremiah R; Patel, Hetal M; Koff, Matthew D; Jensen, Jens T; Reddy, Sundara; Ruoff, Kathryn L; Heard, Stephen O; Dodds, Thomas M; Beach, Michael L; Yeager, Mark P

    2015-04-01

    Gram-negative organisms are a major health care concern with increasing prevalence of infection and community spread. Our primary aim was to characterize the transmission dynamics of frequently encountered gram-negative bacteria in the anesthesia work area environment (AWE). Our secondary aim was to examine links between these transmission events and 30-day postoperative health care-associated infections (HCAIs). Gram-negative isolates obtained from the AWE (patient nasopharynx and axilla, anesthesia provider hands, and the adjustable pressure-limiting valve and agent dial of the anesthesia machine) at 3 major academic medical centers were identified as possible intraoperative bacterial transmission events by class of pathogen, temporal association, and phenotypic analysis (analytical profile indexing). The top 5 frequently encountered genera were subjected to antibiotic disk diffusion sensitivity to identify epidemiologically related transmission events. Complete multivariable logistic regression analysis and binomial tests of proportion were then used to examine the relative contributions of reservoirs of origin and within- and between-case modes of transmission, respectively, to epidemiologically related transmission events. Analyses were conducted with and without the inclusion of duplicate transmission events of the same genera occurring in a given study unit (first and second case of the day in each operating room observed) to examine the potential effect of statistical dependency. Transmitted isolates were compared by pulsed-field gel electrophoresis to disease-causing bacteria for 30-day postoperative HCAIs. The top 5 frequently encountered gram-negative genera included Acinetobacter, Pseudomonas, Brevundimonas, Enterobacter, and Moraxella that together accounted for 81% (767/945) of possible transmission events. For all isolates, 22% (167/767) of possible transmission events were identified by antibiotic susceptibility patterns as epidemiologically related

  11. Exploring the hidden potential of fosfomycin for the fight against severe Gram-negative infections.

    Science.gov (United States)

    Saiprasad, P V; Krishnaprasad, K

    2016-01-01

    Gram-negative resistance is a serious global crisis putting the world on the cusp of 'pre-antibiotic era'. This serious crisis has been catalysed by the rapid increase in carbapenem-resistant Enterobacteriaceae (CRE). Spurge in colistin usage to combat CRE infections leads to the reports of (colistin and carbapenem resistant enterobacteriaceae) CCRE (resistance to colistin in isolates of CRE) infections further jeopardising our last defence. The antibacterial apocalypse imposed by global resistance crisis requires urgent alternative therapeutic options. Interest in the use of fosfomycin renewed recently for serious systemic infections caused by multidrug-resistant Enterobacteriaceae. This review aimed at analysing the recent evidence on intravenous fosfomycin to explore its hidden potential, especially when fosfomycin disodium is going to be available in India. Although a number of promising evidence are coming up for fosfomycin, there are still areas where more work is required to establish intravenous fosfomycin as the last resort antibacterial for severe Gram-negative infections.

  12. Increased genetic variability for symbiotic nitrogen fixation in green gram (Vigna radiata L.)

    International Nuclear Information System (INIS)

    Rosaiah, G.; Kumari, D.S.; Satyanarayana, A.; Seenaiah, P.

    1989-01-01

    Full text: When green gram is planted after rice in Andhra Pradesh, its nitrogen fixation relies upon local rhizobia that have been able to survive the stress of 5-6 months submergence. No rhizobia strain isolated elsewhere was found superior to native rhizobia. Thus improvement of the host may be the only practicable way to improve nitrogen fixation. 15 mutants obtained from gamma irradiated green gram variety 'LGG 127' were tested along with the parent and the cultivar 'Pant Mung 2'. Nodule no. per plant was higher in the mutants. There was also considerable variation in dry weight of nodules per plant and in seed yield. However the number of nodules per plant showed no correlation with seed yield, nodule size may be more relevant. The N content of the shoots at anthesis was positively correlated with dry weight of nodules, seed protein % and seed yield per plant. (author)

  13. Language Classification using N-grams Accelerated by FPGA-based Bloom Filters

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, A; Gokhale, M

    2007-09-13

    N-Gram (n-character sequences in text documents) counting is a well-established technique used in classifying the language of text in a document. In this paper, n-gram processing is accelerated through the use of reconfigurable hardware on the XtremeData XD1000 system. Our design employs parallelism at multiple levels, with parallel Bloom Filters accessing on-chip RAM, parallel language classifiers, and parallel document processing. In contrast to another hardware implementation (HAIL algorithm) that uses off-chip SRAM for lookup, our highly scalable implementation uses only on-chip memory blocks. Our implementation of end-to-end language classification runs at 85x comparable software and 1.45x the competing hardware design.

  14. Quorum-Sensing Signal-Response Systems in Gram-Negative Bacteria

    Science.gov (United States)

    Papenfort, Kai; Bassler, Bonnie

    2016-01-01

    Abstract / Preface Bacteria use quorum sensing to orchestrate gene expression programmes that underlie collective behaviours. Quorum sensing relies on the production, release, detection and group-level response to extracellular signalling molecules, which are called autoinducers. Recent work has discovered new autoinducers in Gram-negative bacteria, shown how these molecules are recognized by cognate receptors, revealed new regulatory components that are embedded in canonical signalling circuits and identified novel regulatory network designs. In this Review we examine how, together, these features of quorum sensing signal–response systems combine to control collective behaviours in Gram-negative bacteria and we discuss the implications for host–microbial associations and antibacterial therapy. PMID:27510864

  15. Advantages of kangaroo Mother care in Less Than 2000 Grams Low Birth Weight Neonates

    Directory of Open Access Journals (Sweden)

    Mohsen Jafarzadeh

    2011-05-01

    Full Text Available Background:The aim of study was to compare the effect of Kangaroo mother care (KMC and conventional methods of care (CMC in low birth weight babies less than 2000 grams.Method: One hundred babies with birth weight less than 2000 grams and without clinical problem were randomized in two groups; the tervention group (N=50 who received Kangaroo mother care and the control group (N=50 with conventional care. Two groups were compared in daily weight gaining, self confidence of mother, duration of hospitalization, clinical cyanosis and nosocomial infection. Collected data was analyzed by SPSS 11.5 software . Irct ID: IRCT201101091162N16.Results: The KMC babies had better daily weight gaining average [18.31±7.57gm vs. 4.8±16.57gm (P0.05.Conclusions: In this study Kangaroo mother care had better effect on daily weight gaining, mother confidence and shorter duration of hospitalization.

  16. Mars Global Reference Atmospheric Model (Mars-GRAM 3.34): Programmer's Guide

    Science.gov (United States)

    Justus, C. G.; James, Bonnie F.; Johnson, Dale L.

    1996-01-01

    This is a programmer's guide for the Mars Global Reference Atmospheric Model (Mars-GRAM 3.34). Included are a brief history and review of the model since its origin in 1988 and a technical discussion of recent additions and modifications. Examples of how to run both the interactive and batch (subroutine) forms are presented. Instructions are provided on how to customize output of the model for various parameters of the Mars atmosphere. Detailed descriptions are given of the main driver programs, subroutines, and associated computational methods. Lists and descriptions include input, output, and local variables in the programs. These descriptions give a summary of program steps and 'map' of calling relationships among the subroutines. Definitions are provided for the variables passed between subroutines through common lists. Explanations are provided for all diagnostic and progress messages generated during execution of the program. A brief outline of future plans for Mars-GRAM is also presented.

  17. Operation of the TSTA (Tritium Systems Test Assembly) with 100 gram tritium

    International Nuclear Information System (INIS)

    Sherman, R.H.; Bartlit, J.R.

    1988-01-01

    In March of 1988 full operation of the 4-column isotope separation system (ISS) was realized in runs that approximated the design load of tritium. Previous operations had been fraught with operating difficulties principally due to external systems. This report will examine the recent highly successful 6-day period of operation. During this time the system was cooled from room temperature, loaded with hydrogen isotopes including 109 grams of tritium, integrated with the transfer pumping, impurity injection, and impurity removal systems, as well as the remote computer control system. At the end of the operation 12 grams of tritium having a measured purity of 99.987% (remainder deuterium) were offloaded from the system. Observed profiles in the columns in general agree with computer models. A Height Equivalent to a Theoretical Plate (HETP) of 5.0 cm is confirmed. 3 refs., 5 figs

  18. [Simultaneously preparation of grams of high purity tyrosol, crenulatin and salidroside from Rhodiola crenulata].

    Science.gov (United States)

    Luo, Xin; Wang, Xue-jing; Li, Shi-ping; Zhang, Qiao; Zhao, Yi-wu; Huang Wen-zhe; Wang, Zhen-zhong; Xiao, Wei

    2015-04-01

    Tyrosol, crenulatin and salidroside are the main active constituents of Rhodiola crenulata, with extensive pharmacological activities. In the study, grams of high purity tyrosol, crenulatin and salidroside were simultaneously separated from R. crenulata by the first time. Firstly, R. crenulata was extracted by 70% alcohol. Then, with the yields of three compounds as the index, the macroporous resin was optimized. At last, grams of high purity tyrosol, crenulatin and salidroside were isolated by D-101 macroporousresin, purified by column chromatography. Detected by HPLC, the purity of three compounds were higher than 98%. This method has the advantages of simple process and operation, less dosage of organic solvent, highly yield and reproducibility, suitable for the simultaneously preparation of tyrosol, crenulatin and salidroside.

  19. Desarrollo y evaluación de una prueba de reacción en cadena de la polimerasa (PCR, utilizando la secuencia del gen hilA para diagnóstico de fiebre entérica por Salmonella spp.

    Directory of Open Access Journals (Sweden)

    Miryan Margot Sánchez

    2004-06-01

    Full Text Available El diagnóstico de fiebre entérica por Salmonella spp. se basa en el aislamiento de la bacteria en hemocultivos el cual consume tiempo, no siempre está disponible y tiene poca utilidad en pacientes con tratamiento antibiótico previo. Por consiguiente, se hace necesario el desarrollo de una prueba rápida, sensible y específica para el diagnóstico de fiebre entérica. Salmonella spp. utiliza el gen hilA (componente de la isla de patogenicidad I para invadir células epiteliales y producir infección. Al usar la secuencia de este gen se diseñó una prueba de PCR para detectar la bacteria en sangre y se evaluó su sensibilidad, especificidad, valor predictivo positivo y valor predictivo negativo, utilizando la metodología prueba de una prueba. La prueba de oro fue el hemocultivo. Se estudiaron 34 individuos con sintomatología de fiebre entérica con aislamiento de Salmonella serotipo Typhi en hemocultivos; 35 individuos con sepsis por otros bacilos Gram negativos aislados de hemocultivo (Klebsiella pneumoniae, 9; Serratia marcescens, 5; Escherichia coli, 4; Pseudomonas aeruginosa, 9; Providencia alcalifaciens, 4, y Enterobacter cloacae, 4 y 150 muestras de sangre de voluntarios asintomáticos. La sensibilidad, especificidad, valor pronóstico positivo y valor pronóstico negativo de la PCR fue del 100%. El número mínimo de UFC/ml que la PCR detecta en sangre es de 10.

  20. Molecular studies on bacteriophage endolysins and their potential to control gram-negative bacteria

    OpenAIRE

    Oliveira, Hugo Alexandre Mendes

    2014-01-01

    Thesis for PhD degree in Chemical and Biological Engineeering Bacteriophages are viruses that specifically infect bacterial hosts to reproduce. At the end of the infection cycle, progeny virions are confronted with a rigid cell wall that impedes their release into the environment. Consequently, bacteriophages encode hydrolytic enzymes, called endolysins, to digest the peptidoglycan and cause bacteriolysis. In contrast to their extensively studied counterparts, active against Gram-positi...

  1. Case of Mycobacterium tuberculosis meningitis: Gram staining as a useful initial diagnostic clue for tuberculous meningitis.

    Science.gov (United States)

    Kawakami, Sayoko; Kawamura, Yasuyosi; Nishiyama, Kyouhei; Hatanaka, Hiroki; Fujisaki, Ryuichi; Ono, Yasuo; Miyazawa, Yukihisa; Nishiya, Hajime

    2012-12-01

    A 32-year-old man was admitted to our hospital because of fever, headache, and loss of consciousness. Four days before admission, he had had difficulty speaking. On the day of admission, his colleague had found him to be unconscious and lying on his back. He was admitted to our hospital. The temperature at the eardrum was 35.2°C. Neurologic evaluation was negative. Computed tomography (CT) scan of the brain showed slight ventricular enlargement bilaterally. An X-ray film of the chest showed no abnormality. On the second hospital day, neck stiffness was noted. The cerebrospinal fluid (CSF) contained 870 white cells/μl, most of which were neutrophils; the glucose level in the CSF was 10 mg/dl, and the protein level was 140 mg/dl. Stained smears of the CSF, including Gram staining and India-ink preparations, disclosed no microorganisms. Capsular antigen tests for several bacteria were negative. Antimicrobial agents were started. However, by changing the microscope focus slightly while viewing Gram stains of the CSF, we could see brightened and Gram-positive bacilli that had been phagocytosed by neutrophils. This finding suggested the presence of Mycobacterium tuberculosis. Ziehl-Neelsen staining of the CSF and gastric juice revealed anti-acid bacilli. Polymerase chain reaction for M. tuberculosis in the gastric juice was positive. This case showed that Gram staining could be useful as an initial adjunct for the diagnosis of tuberculous meningitis, particularly when the CSF shows predominantly neutrocytic pleocytosis, but no other evidence of bacterial meningitis.

  2. Diagnostic accuracy of cerebrospinal fluid gram stain in children with suspected bacterial meningitis.

    Science.gov (United States)

    Brizzi, Kate; Hines, Elizabeth M; McGowan, Karin L; Shah, Samir S

    2012-02-01

    This cross-sectional study included 1938 children undergoing lumbar puncture; 21 (1.1%) cases were classified as definite (n = 17) or probable (n = 4) bacterial meningitis. Gram stain sensitivity was 94.1% (95% confidence interval, 71.3%-99.9%) for those with definite meningitis; the positive predictive value was 47.1% (95% confidence interval, 29.8%-64.9%). The sensitivity was 95.2% for those with definite or probable meningitis. Antibiotic pretreatment did not affect results.

  3. Biofilm detection in chronic rhinosinusitis by combined application of hematoxylin-eosin and gram staining.

    Science.gov (United States)

    Tóth, László; Csomor, Péter; Sziklai, István; Karosi, Tamás

    2011-10-01

    The pathomechanism of chronic rhinosinusitis with nasal polyposis (CRS/NP) seems to be unclear. Bacterial-, fungal- and combined biofilms might play a potential role in the pathogenesis of various inflammatory diseases and recently in CRS/NP. A prospective, blinded observational study was performed to confirm that the combination of conventional hematoxylin-eosin (HE) and Gram staining protocols could be used to detect bacterial and fungal biofilms in patients with CRS/NP. A total of 50 patients with CRS/NP undergoing endoscopic sinus surgery (ESS) were analyzed. The negative control group consisted of 12 patients undergoing septoplasty for nasal obstruction without CRS/NP. The nasal polyps and inferior turbinate mucosa specimens applied as negative controls were processed to HE and Gram staining. Biofilm was detected in 44 of 50 patients with CRS/NP and in none of 12 negative controls. In our series, HE method showed an obvious correlation with the results of Gram staining and was allocated to be a good predictor of biofilm existence. It was found that the microscopic structure and thickness of biofilms were strongly associated with the integrity of nasal mucosa and with the characteristics of subepithelial cellular infiltration. This study confirmed the presence of bacterial and fungal biofilms on the surface of NPs obtained from patients with CRS. Since biofilms may affect the severity and recurrence rate of CRS treated by ESS they should be detected histologically. In conclusion, HE staining combined with Gram protocol is a robust and reliable method for the detection of bacterial and fungal biofilms in CRS/NP.

  4. Coexpression of ESBL, Amp C and MBL in gram negative bacilli

    OpenAIRE

    Ruturaj M. Kolhapure; Ashwin Kumar; HRV Rajkumar

    2015-01-01

    Background: Resistant bacteria are emerging worldwide as a threat to the favourable outcome of common infections in community and hospital settings. Extended Spectrum Beta-Lactamases (ESBLs), AmpC beta lactamases and Metallo-beta Lactamases (MBL) are the three important mechanism of resistance to beta lactam drugs in the bacteria. The objective of the study was to screen gram negative isolates for co-expression of extended spectrum beta-lactamase, Amp C beta-lactamase and Metallo beta-lactama...

  5. Polymers for binding of the gram-positive oral pathogen Streptococcus mutans

    Science.gov (United States)

    Magennis, Eugene P.; Francini, Nora; Mastrotto, Francesca; Catania, Rosa; Redhead, Martin; Fernandez-Trillo, Francisco; Bradshaw, David; Churchley, David; Winzer, Klaus; Alexander, Cameron

    2017-01-01

    Streptococcus mutans is the most significant pathogenic bacterium implicated in the formation of dental caries and, both directly and indirectly, has been associated with severe conditions such as multiple sclerosis, cerebrovascular and peripheral artery disease. Polymers able to selectively bind S. mutans and/or inhibit its adhesion to oral tissue in a non-lethal manner would offer possibilities for addressing pathogenicity without selecting for populations resistant against bactericidal agents. In the present work two libraries of 2-(dimethylamino)ethyl methacrylate (pDMAEMA)-based polymers were synthesized with various proportions of either N,N,N-trimethylethanaminium cationic- or sulfobetaine zwitterionic groups. These copolymers where initially tested as potential macromolecular ligands for S. mutans NCTC 10449, whilst Escherichia coli MG1655 was used as Gram-negative control bacteria. pDMAEMA-derived materials with high proportions of zwitterionic repeating units were found to be selective for S. mutans, in both isolated and S. mutans–E. coli mixed bacterial cultures. Fully sulfobetainized pDMAEMA was subsequently found to bind/cluster preferentially Gram-positive S. mutans and S. aureus compared to Gram negative E. coli and V. harveyi. A key initial stage of S. mutans pathogenesis involves a lectin-mediated adhesion to the tooth surface, thus the range of potential macromolecular ligands was further expanded by investigating two glycopolymers bearing α-mannopyranoside and β-galactopyranoside pendant units. Results with these polymers indicated that preferential binding to either S. mutans or E. coli can be obtained by modulating the glycosylation pattern of the chosen multivalent ligands without incurring unacceptable cytotoxicity in a model gastrointestinal cell line. Overall, our results allowed to identify a structure–property relationship for the potential antimicrobial polymers investigated, and suggest that preferential binding to Gram-positive S

  6. Metallo beta lactamase mediated resistance in Carbapenem resistant gram-negative bacilli: A cause for concern

    Directory of Open Access Journals (Sweden)

    Malini Jagannatha Rao, Shruti A Harle, Padmavathy M, Umapathy BL, Navaneeth BV

    2014-04-01

    Full Text Available Introduction: The emergence of acquired metallo-β-lactamases (MBL in Gram-negative bacilli is becoming a therapeutic challenge, as these enzymes usually possess a broad hydrolysis profile that includes carbapenems, extended-spectrum β-lactams. Aim: To detect Extended spectrum β-lactamases and metallo-β-lactamase in carbapenem resistant Gram negative clinical isolates from various clinical specimens and to evaluate their antibiotic susceptibility patterns. Material and Methods: A total of 100 non duplicates imipenem resistant isolates were tested for the presence of extended spectrum β-lactamases by phenotypic confirmatory test, metallo-β-lactamases by Double disk synergy test with various distances from edge to edge (10mm,15mm,20mm, between the IPM and EDTA and combined disc test. Result: Of the 100 IMP resistant isolates screened 30 (30% were MBL positive by phenotypic methods, i.e., double disk synergy test and combined disc test. Co-existence of Extended spectrum β-lactamases and MBL were detected in 3 (30%. All the 30 MBL positive isolates had shown synergy at (100% at 10 mm distance, 27 (90% isolates had shown synergy at 15 mm distance and 13 (43.4% isolates were shown synergy at 20 mm distance. All the 30 MBLs producers were multidrug resistant and 27 (90% were sensitive to colistin (CL. All MBL positive Pseudomonas aeruginosa were sensitive to polymyxin B (100µg. Conclusion: Microbiologists are now facing a challenge of drug resistance due to MBL production. Although CLSI guidelines do not quote about the ESBL detection in Pseudomonas aeruginosa MBLs and ESBL have to be detected in them. The use of combination tests would increase the sensitivity to detect the presence of MBL among the clinical isolates of Gram-negative bacilli. The spread of MBL producing Gram negative organism can be prevented if they are detected in all isolates and routinely adopted in all laboratories.

  7. Survival of Gram-Negative Bacteria on Plastic Compounded with Hexachlorophene

    Science.gov (United States)

    Taylor, Gerald F.

    1970-01-01

    Gram-negative bacteria representing nine genera were screened for their ability to survive surface exposure to polyethylene sheet plastic containing chemically compounded hexachlorophene (0.25%). Subcultures were made at hourly intervals over a 6-hr period of time. An exceedingly large drop in viable cells beginning at the 1-hr exposure was noted for each genus except one tested on the hexachlorophene-plastic, whereas most nonadditive controls grew bacterial colonies too numerous to count. PMID:5415208

  8. Sensing the enemy within: how macrophages detect intracellular Gram-negative bacteria

    OpenAIRE

    Demon, Dieter; Vande Walle, Lieselotte; Lamkanfi, Mohamed

    2014-01-01

    Caspase-11 contributes to host defense against Gram-negative bacterial pathogens by inducing an inflammatory form of programmed cell death in infected cells. Lipopolysaccharides (LPS) have been identified as the microbial agents that stimulate caspase-11 activation; however, the mechanism of LPS detection has been unknown. In a recent study, Shao and colleagues demonstrate that caspase-11 and its human homologues, caspases -4 and -5, unexpectedly act as direct sensors of cytosolic LPS.

  9. Chromogenic method for rapid isolation of recA-like mutants of gram-negative bacteria.

    OpenAIRE

    Barbe, J; Fernandez de Henestrosa, A R; Calero, S; Gibert, I

    1991-01-01

    We have devised a rapid and widely applicable color test for detecting recA-like mutants of gram-negative bacteria. The technique depends on decreased expression of an Escherichia coli recA-lacZ fusion in recA mutants and uses a broad-host-range plasmid to transfer the fusion gene into new species. We describe the isolation of a recA-like mutant of Pseudomonas syringae by this technique.

  10. Real Time Filtering of Tweets Using Wikipedia Concepts and Google Tri-gram Semantic Relatedness

    Science.gov (United States)

    2015-11-20

    Real Time Filtering of Tweets Using Wikipedia Concepts and Google Tri-gram Semantic Relatedness Anh Dang1, Raheleh Makki1, Abidalrahman Moh’d1...group name “DALTREC”. Our proposed approach for this year’s filtering task is based on using Wikipedia and Google Trigram for calculating the semantic...lucene.apache.org/core/ Fig. 1: The framework of the proposed methods for the real-time filtering task. Semantic similary between two texts is computed using Google

  11. Nanotransformation of vancomycin overcomes the intrinsic resistance of Gram-negative bacteria

    OpenAIRE

    Ivanova, Kristina Dimitrova; Hoyo Pérez, Javier; Francesko, Antonio; Tzanov, Tzanko

    2017-01-01

    The increased emergence of antibiotic-resistant bacteria is a growing public health concern, and although new drugs are constantly being sought, the pace of development is slow compared with the evolution and spread of multidrug- resistant species. In this study, we developed a novel broad-spectrum antimicrobial agent by simply transforming vancomycin into nanoform using sonochemistry. Vancomycin is a glycopeptide antibiotic largely used for the treatment of infections caused by Gram-positive...

  12. Development of Methionyl-tRNA Synthetase Inhibitors as Antibiotics for Gram-Positive Bacterial Infections.

    Science.gov (United States)

    Faghih, Omeed; Zhang, Zhongsheng; Ranade, Ranae M; Gillespie, J Robert; Creason, Sharon A; Huang, Wenlin; Shibata, Sayaka; Barros-Álvarez, Ximena; Verlinde, Christophe L M J; Hol, Wim G J; Fan, Erkang; Buckner, Frederick S

    2017-11-01

    Antibiotic-resistant bacteria are widespread and pose a growing threat to human health. New antibiotics acting by novel mechanisms of action are needed to address this challenge. The bacterial methionyl-tRNA synthetase (MetRS) enzyme is essential for protein synthesis, and the type found in Gram-positive bacteria is substantially different from its counterpart found in the mammalian cytoplasm. Both previously published and new selective inhibitors were shown to be highly active against Gram-positive bacteria with MICs of ≤1.3 μg/ml against Staphylococcus , Enterococcus , and Streptococcus strains. Incorporation of radioactive precursors demonstrated that the mechanism of activity was due to the inhibition of protein synthesis. Little activity against Gram-negative bacteria was observed, consistent with the fact that Gram-negative bacterial species contain a different type of MetRS enzyme. The ratio of the MIC to the minimum bactericidal concentration (MBC) was consistent with a bacteriostatic mechanism. The level of protein binding of the compounds was high (>95%), and this translated to a substantial increase in MICs when the compounds were tested in the presence of serum. Despite this, the compounds were very active when they were tested in a Staphylococcus aureus murine thigh infection model. Compounds 1717 and 2144, given by oral gavage, resulted in 3- to 4-log decreases in the bacterial load compared to that in vehicle-treated mice, which was comparable to the results observed with the comparator drugs, vancomycin and linezolid. In summary, the research describes MetRS inhibitors with oral bioavailability that represent a class of compounds acting by a novel mechanism with excellent potential for clinical development. Copyright © 2017 American Society for Microbiology.

  13. Polymers for binding of the gram-positive oral pathogen Streptococcus mutans.

    Science.gov (United States)

    Magennis, Eugene P; Francini, Nora; Mastrotto, Francesca; Catania, Rosa; Redhead, Martin; Fernandez-Trillo, Francisco; Bradshaw, David; Churchley, David; Winzer, Klaus; Alexander, Cameron; Mantovani, Giuseppe

    2017-01-01

    Streptococcus mutans is the most significant pathogenic bacterium implicated in the formation of dental caries and, both directly and indirectly, has been associated with severe conditions such as multiple sclerosis, cerebrovascular and peripheral artery disease. Polymers able to selectively bind S. mutans and/or inhibit its adhesion to oral tissue in a non-lethal manner would offer possibilities for addressing pathogenicity without selecting for populations resistant against bactericidal agents. In the present work two libraries of 2-(dimethylamino)ethyl methacrylate (pDMAEMA)-based polymers were synthesized with various proportions of either N,N,N-trimethylethanaminium cationic- or sulfobetaine zwitterionic groups. These copolymers where initially tested as potential macromolecular ligands for S. mutans NCTC 10449, whilst Escherichia coli MG1655 was used as Gram-negative control bacteria. pDMAEMA-derived materials with high proportions of zwitterionic repeating units were found to be selective for S. mutans, in both isolated and S. mutans-E. coli mixed bacterial cultures. Fully sulfobetainized pDMAEMA was subsequently found to bind/cluster preferentially Gram-positive S. mutans and S. aureus compared to Gram negative E. coli and V. harveyi. A key initial stage of S. mutans pathogenesis involves a lectin-mediated adhesion to the tooth surface, thus the range of potential macromolecular ligands was further expanded by investigating two glycopolymers bearing α-mannopyranoside and β-galactopyranoside pendant units. Results with these polymers indicated that preferential binding to either S. mutans or E. coli can be obtained by modulating the glycosylation pattern of the chosen multivalent ligands without incurring unacceptable cytotoxicity in a model gastrointestinal cell line. Overall, our results allowed to identify a structure-property relationship for the potential antimicrobial polymers investigated, and suggest that preferential binding to Gram-positive S

  14. A New Family of Lysozyme Inhibitors Contributing to Lysozyme Tolerance in Gram-Negative Bacteria

    OpenAIRE

    Callewaert, Lien; Aertsen, Abram; Deckers, Daphne; Vanoirbeek, Kristof G. A.; Vanderkelen, Lise; Van Herreweghe, Joris M.; Masschalck, Barbara; Nakimbugwe, Dorothy; Robben, Johan; Michiels, Chris W.

    2008-01-01

    Lysozymes are ancient and important components of the innate immune system of animals that hydrolyze peptidoglycan, the major bacterial cell wall polymer. Bacteria engaging in commensal or pathogenic interactions with an animal host have evolved various strategies to evade this bactericidal enzyme, one recently proposed strategy being the production of lysozyme inhibitors. We here report the discovery of a novel family of bacterial lysozyme inhibitors with widespread homologs in gram-negative...

  15. Recovery of vancomycin-resistant gram-positive cocci from children.

    OpenAIRE

    Green, M; Wadowsky, R M; Barbadora, K

    1990-01-01

    A cross-sectional survey of vancomycin-resistant gram-positive cocci (VRGPC) in the feces of children was initiated after several bacteremic infections with these organisms occurred at our hospital. A selective medium consisting of colistin-nalidixic acid agar, 5% sheep blood, vancomycin (5 mg/liter), and amphotericin B (8 mg/liter) was developed to isolate VRGPC. A single stool specimen submitted to the clinical microbiology laboratory from each of 48 patients was inoculated onto the medium....

  16. GramCheck : un corrector gramatical para el español

    OpenAIRE

    Ramírez Bustamante, Flora; Sánchez León, Fernando

    1996-01-01

    This paper presents a grammar and style checker demonstrator for Spanish native writers developed within the project GramCheck. Besides a grammar and style error typology for Spanish, a linguistically motivated approach to detection and diagnosis is presented. The demonstrator includes full coverage for agreement errors and certain head-argument relation issues. It also provides correction by means of an analysis-transfer-synthesis cycle.

  17. Gram-scale production of a basidiomycetous laccase in Aspergillus niger.

    Science.gov (United States)

    Mekmouche, Yasmina; Zhou, Simeng; Cusano, Angela M; Record, Eric; Lomascolo, Anne; Robert, Viviane; Simaan, A Jalila; Rousselot-Pailley, Pierre; Ullah, Sana; Chaspoul, Florence; Tron, Thierry

    2014-01-01

    We report on the expression in Aspergillus niger of a laccase gene we used to produce variants in Saccharomyces cerevisiae. Grams of recombinant enzyme can be easily obtained. This highlights the potential of combining this generic laccase sequence to the yeast and fungal expression systems for large-scale productions of variants. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  18. Detection of Cross Site Scripting Attack in Wireless Networks Using n-Gram and SVM

    Directory of Open Access Journals (Sweden)

    Jun-Ho Choi

    2012-01-01

    Full Text Available Large parts of attacks targeting the web are aiming at the weak point of web application. Even though SQL injection, which is the form of XSS (Cross Site Scripting attacks, is not a threat to the system to operate the web site, it is very critical to the places that deal with the important information because sensitive information can be obtained and falsified. In this paper, the method to detect themalicious SQL injection script code which is the typical XSS attack using n-Gram indexing and SVM (Support Vector Machine is proposed. In order to test the proposed method, the test was conducted after classifying each data set as normal code and malicious code, and the malicious script code was detected by applying index term generated by n-Gram and data set generated by code dictionary to SVM classifier. As a result, when the malicious script code detection was conducted using n-Gram index term and SVM, the superior performance could be identified in detecting malicious script and the more improved results than existing methods could be seen in the malicious script code detection recall.

  19. Preemptive antibiotic treatment based on gram staining reduced the incidence of ARDS in mechanically ventilated patients.

    Science.gov (United States)

    Matsushima, Asako; Tasaki, Osamu; Shimizu, Kentaro; Tomono, Kazunori; Ogura, Hiroshi; Shimazu, Takeshi; Sugimoto, Hisashi

    2008-08-01

    Ventilator-associated pneumonia (VAP) is one of the major complications in the intensive care unit. VAP sometimes results in acute respiratory distress syndrome (ARDS), and the associated mortality is high. We hypothesized that preemptive antibiotic therapy based on results of bedside gram staining would reduce the incidence of VAP. Patients who were endotracheally intubated in our intensive care unit for more than 72 hours were included. Patients younger than 16 years of age or patients died because of brain death were excluded. The study was divided into two periods. During the first period, we used antibiotics according to the American Thoracic Society guidelines. During the second period, antibiotics were given according to the results of bedside gram staining even before radiographic infiltrate appeared. One hundred twenty-eight patients and 133 patients were included in the first and second periods, respectively. The incidence of VAP was significantly decreased in the second period (first period, 22%; second period, 9%, p gram staining significantly reduced the incidences of VAP and ARDS without an increase in the use of antibiotics.

  20. ESTABLISHING NORMAL FECAL FLORA IN WILD AUSTRALIAN PASSERINE BIRDS BY USE OF THE FECAL GRAM STAIN.

    Science.gov (United States)

    Latham, Benjamin; Leishman, Alan; Martin, John; Phalen, David

    2017-09-01

    The purpose of this study was to determine the normal fecal bacterial and fungal flora and parasite prevalence in wild passerine birds found at the Australian Botanic Garden (Mount Annan, New South Wales). Wild passerine birds (n = 186) from 28 species were captured with mist nets. Fecal Gram stains (n = 155) were made from 26 species and analyzed for bacterial density, Gram stain morphology, and the presence of yeast. Fecal wet preparations (n = 139) were made from 24 passerine species and were analyzed for parasites. Our results showed that 81.9% of passerines sampled had bacteria present in their feces. The bacteria found were entirely Gram positive and consisted predominantly of cocci. Individuals that were caught on multiple occasions were found to have stable bacterial populations, apart from the red-browed finch (Neochmia temporalis). Insectivores had higher bacterial densities and cocci proportions than nectarivores had. Yeasts were rare in most species, with the exception of the bell miner (Manorina melanophrys) and noisy miner (Manorina melanocephala). The yeast, Macrorhabdus ornithogaster, and parasites were not observed in any fecal samples. These results will help practitioners to assess the health of Australian passerine species submitted for care or housed in zoological collections.

  1. Emergence of Pan-drug resistance amongst gram negative bacteria! The First case series from India

    Directory of Open Access Journals (Sweden)

    Abdul Ghafur

    2014-09-01

    Full Text Available Objective: Increasing prevalence of carbapenem resistant Gram negative bacteria is a serious clinical and public health challenge. Bacteria resistant to all available antibiotics (Pan Drug Resistance herald the onset of post antibiotics era. We hereby report clinical profile of 13 patients with pan drug resistant gram negative isolates. Methods:Retrospective analysis of 13 patients with pan drug resistant gram negative isolates over the last 18 months was done by medical records review. Identification of the isolates and susceptibility testing was done using VITEK auto analyzer in concordance with the corresponding CLSI guidelines. Results:Out of four patients with bacteremic isolates, three patients received colistin based combination therapy. Though two of these patients had microbiologic clearance, all the three died. Out of the 9 patients with non bacteremic isolates, 4 had infection and 5 had colonization. Three (out of four were treated with combination therapy including colistin and one patient received colistin monotherapy. All four patients had microbiological clearance. Three patients had clinical cure and were discharged. One patient later developed bacteremia and died. Conclusion:Infections, particularly blood stream with pan drug resistant organisms has a higher mortality. Urgent studies to reevaluate existing therapeutic options and research into new antibiotic molecules are the need of the hour. J Microbiol Infect Dis 2014; 4(3: 86-91

  2. Electron beam irradiation: a technology for quarantine disinfestation of green gram seeds against Callsobruchus maculatus

    International Nuclear Information System (INIS)

    Bhalla, Shashi; Srinivasan, K.; Singh, Subadas; Thakur, Manju; Sharma, S.K.; Pramod, R.; Dwivedi, J.; Bapna, S.C.

    2010-01-01

    Green gram (Vigna radiata (L.) Wilkzec) an important legume crop in India is grown in 33.4 lakh hectares. India accounts for ∼ 60% of the world's green gram area but contributes only 47% of its production. Major constraint in storage is the pulse beetle Callosobruchus maculatus Fab. (Coleoptera: Bruchidae), which may cause damage upto 100%. It is widespread throughout tropics and sub-tropics with wide host range and also has different strains. Fumigation with methyl bromide (MB) has been the most widely applied management practice for its control. However, the ozone depleting effect of MB has led to restrictions in its use. Therefore, there is a need for an alternative strategy for controlling the pests. Irradiation, an approved technology by International Plant Protection Convention, seems to be a viable non-chemical, residue-free strategy. Therefore, present studies were conducted to see the efficacy of electron beam (EB) irradiation as quarantine disinfestation treatment against green gram seeds infested with different stages of the target pest, C. maculatus

  3. A synbio approach for selection of highly expressed gene variants in Gram-positive bacteria.

    Science.gov (United States)

    Ferro, Roberto; Rennig, Maja; Hernández-Rollán, Cristina; Daley, Daniel O; Nørholm, Morten H H

    2018-03-08

    The market for recombinant proteins is on the rise, and Gram-positive strains are widely exploited for this purpose. Bacillus subtilis is a profitable host for protein production thanks to its ability to secrete large amounts of proteins, and Lactococcus lactis is an attractive production organism with a long history in food fermentation. We have developed a synbio approach for increasing gene expression in two Gram-positive bacteria. First of all, the gene of interest was coupled to an antibiotic resistance gene to create a growth-based selection system. We then randomised the translation initiation region (TIR) preceding the gene of interest and selected clones that produced high protein titres, as judged by their ability to survive on high concentrations of antibiotic. Using this approach, we were able to significantly increase production of two industrially relevant proteins; sialidase in B. subtilis and tyrosine ammonia lyase in L. lactis. Gram-positive bacteria are widely used to produce industrial enzymes. High titres are necessary to make the production economically feasible. The synbio approach presented here is a simple and inexpensive way to increase protein titres, which can be carried out in any laboratory within a few days. It could also be implemented as a tool for applications beyond TIR libraries, such as screening of synthetic, homologous or domain-shuffled genes.

  4. The Mechanisms of Virulence Regulation by Small Noncoding RNAs in Low GC Gram-Positive Pathogens

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    Stephanie Pitman

    2015-12-01

    Full Text Available The discovery of small noncoding regulatory RNAs (sRNAs in bacteria has grown tremendously recently, giving new insights into gene regulation. The implementation of computational analysis and RNA sequencing has provided new tools to discover and analyze potential sRNAs. Small regulatory RNAs that act by base-pairing to target mRNAs have been found to be ubiquitous and are the most abundant class of post-transcriptional regulators in bacteria. The majority of sRNA studies has been limited to E. coli and other gram-negative bacteria. However, examples of sRNAs in gram-positive bacteria are still plentiful although the detailed gene regulation mechanisms behind them are not as well understood. Strict virulence control is critical for a pathogen’s survival and many sRNAs have been found to be involved in that process. This review outlines the targets and currently known mechanisms of trans-acting sRNAs involved in virulence regulation in various gram-positive pathogens. In addition, their shared characteristics such as CU interaction motifs, the role of Hfq, and involvement in two-component regulators, riboswitches, quorum sensing, or toxin/antitoxin systems are described.

  5. Blue green alga mediated synthesis of gold nanoparticles and its antibacterial efficacy against Gram positive organisms

    Energy Technology Data Exchange (ETDEWEB)

    Uma Suganya, K.S. [Centre for Ocean Research, Sathyabama University, Chennai 600 119 (India); Govindaraju, K., E-mail: govindtu@gmail.com [Centre for Ocean Research, Sathyabama University, Chennai 600 119 (India); Ganesh Kumar, V.; Stalin Dhas, T.; Karthick, V. [Centre for Ocean Research, Sathyabama University, Chennai 600 119 (India); Singaravelu, G. [Nanoscience Division, Department of Zoology, Thiruvalluvar University, Vellore 632115 (India); Elanchezhiyan, M. [Department of Microbiology, Dr ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Chennai 600113 (India)

    2015-02-01

    Biofunctionalized gold nanoparticles (AuNPs) play an important role in design and development of nanomedicine. Synthesis of AuNPs from biogenic materials is environmentally benign and possesses high bacterial inhibition and bactericidal properties. In the present study, blue green alga Spirulina platensis protein mediated synthesis of AuNPs and its antibacterial activity against Gram positive bacteria is discussed. AuNPs were characterized using Ultraviolet–visible (UV–vis) spectroscopy, Fluorescence spectroscopy, Fourier Transform-Infrared (FTIR) spectroscopy, Raman spectroscopy, High Resolution-Transmission Electron Microscopy (HR-TEM) and Energy Dispersive X-ray analysis (EDAX). Stable, well defined AuNPs of smaller and uniform shape with an average size of ∼ 5 nm were obtained. The antibacterial efficacy of protein functionalized AuNPs were tested against Gram positive organisms Bacillus subtilis and Staphylococcus aureus. - Highlights: • Size controlled synthesis of gold nanoparticles from blue green alga Spirulina platensis • Stability of gold nanoparticles at different temperatures • Potent antibacterial efficacy against Gram positive organisms.

  6. Gram-Negative Infections in Adult Intensive Care Units of Latin America and the Caribbean

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    Carlos M. Luna

    2014-01-01

    Full Text Available This review summarizes recent epidemiology of Gram-negative infections in selected countries from Latin American and Caribbean adult intensive care units (ICUs. A systematic search of the biomedical literature (PubMed was performed to identify articles published over the last decade. Where appropriate, data also were collected from the reference list of published articles, health departments of specific countries, and registries. Independent cohort data from all countries (Argentina, Brazil, Chile, Colombia, Cuba, Mexico, Trinidad and Tobago, and Venezuela signified a high rate of ICU infections (prevalence: Argentina, 24%; Brazil, 57%. Gram-negative pathogens, predominantly Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli, accounted for >50% of ICU infections, which were often complicated by the presence of multidrug-resistant strains and clonal outbreaks. Empirical use of antimicrobial agents was identified as a strong risk factor for resistance development and excessive mortality. Infection control strategies utilizing hygiene measures and antimicrobial stewardship programs reduced the rate of device-associated infections. To mitigate the poor health outcomes associated with infections by multidrug-resistant Gram-negative bacteria, urgent focus must be placed on infection control strategies and local surveillance programs.

  7. Uso multifuncional e niveis de análise: interface gramática e discurso

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    Roberto Gomes Camacho

    2004-11-01

    Full Text Available 0 conectivo aditivo é empregado não só para estabelecer conjunção de conteúdos, exercendo a função ideacional, representada pela camada da predicação, mas também para estabelecer a conjunção epistêmica e a ilocucionária, perfazendo a função interpessoal, que se acham representadas respectivamente nas camadas da proposição e da frase no modelo de Gramática Funcional (DIK, 1989, 1997. Além do nível intra-oracional, o conectivo atua também no nível textual-interativo. A proposta deste trabalho é demonstrar, por um lado, que o quadro teórico da GF explica satisfatoriamente esse princípio de multifuncionalidade detectado no uso e justificar, por outro, a necessidade de expansão de gramáticas sentenciais, incluindo a GF, para gramáticas do discurso.

  8. Uso multifuncional e niveis de análise: interface gramática e discurso

    Directory of Open Access Journals (Sweden)

    Roberto Gomes Camacho

    2013-11-01

    Full Text Available 0 conectivo aditivo é empregado não só para estabelecer conjunção de conteúdos, exercendo a função ideacional, representada pela camada da predicação, mas também para estabelecer a conjunção epistêmica e a ilocucionária, perfazendo a função interpessoal, que se acham representadas respectivamente nas camadas da proposição e da frase no modelo de Gramática Funcional (DIK, 1989, 1997. Além do nível intra-oracional, o conectivo atua também no nível textual-interativo. A proposta deste trabalho é demonstrar, por um lado, que o quadro teórico da GF explica satisfatoriamente esse princípio de multifuncionalidade detectado no uso e justificar, por outro, a necessidade de expansão de gramáticas sentenciais, incluindo a GF, para gramáticas do discurso.

  9. [Antimicrobial spectrum of dalbavancin. Mechanism of action and in vitro activity against Gram-positive microorganisms].

    Science.gov (United States)

    Cercenado, Emilia

    2017-01-01

    Because of the increase in bacterial resistance, there is a need for new antimicrobial agents. Dalbavancin is a semisynthetic glycopeptide that inhibits the late stages of bacterial cell wall synthesis in the same way as vancomycin, but in addition, its lipophilic side chain anchors dalbavancin to the cellular membrane and allows enhanced activity compared with that of vancomycin. Dalbavancin possesses a broad spectrum of in vitro activity against Gram-positive aerobic and anaerobic microorganisms, being 4-8 times more potent than vancomycin. The spectrum of dalbavancin includes staphylococci, enterococci, streptococci, and anaerobic Gram-positive cocci and bacilli. It is active against different species of multiresistant microorganisms, including methicillin-resistant Staphylococcus aureus and penicillin-resistant viridans streptococci and Streptococcus pneumoniae. Although it shows in vitro activity against Enterococcus spp., it is inactive against isolates expressing the VanA phenotype of vancomycin resistance. It also shows slow bactericidal activity against S. aureus, coagulase-negative staphylococci, and Streptococcus pyogenes. In general, the MIC 90 (minimum inhibitory concentration 90%) against the majority of the microorganisms is 0.06mg/L and, more than 98% of the isolates that have been tested are inhibited at concentrations of ≤ 0.12mg/L. Dalbavancin is an interesting addition to the therapeutic armamentarium for the treatment of infections caused by Gram-positive microorganisms, including multidrug-resistant isolates. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  10. GramHealth: a bottom-up approach to provide preventive healthcare services for unreached community.

    Science.gov (United States)

    Ahmed, Ashir; Kabir, Lutfe; Kai, Eiko; Inoue, Sozo

    2013-01-01

    Insufficient healthcare facilities and unavailability of medical experts in rural areas are the two major reasons that kept the people unreached to healthcare services. Recent penetration of mobile phone and the demand to basic healthcare services, remote health consultancy over mobile phone became popular in developing countries. In this paper, we introduce two such representative initiatives from Bangladesh and discuss the technical challenges they face to serve a remote patient. To solve these issues, we have prototyped a box with necessary diagnostic tools, we call it a "portable clinic" and a software tool, "GramHealth" for managing the patient information. We carried out experiments in three villages in Bangladesh to observe the usability of the portable clinic and verify the functionality of "GramHealth". We display the qualitative analysis of the results obtained from the experiment. GramHealth DB has a unique combination of structured, semi-structured and un-structured data. We are currently looking at these data to see whether these can be treated as BigData and if yes, how to analyze the data and what to expect from these data to make a better clinical decision support.

  11. Engineered Endolysin-Based “Artilysins” To Combat Multidrug-Resistant Gram-Negative Pathogens

    Science.gov (United States)

    Briers, Yves; Walmagh, Maarten; Van Puyenbroeck, Victor; Cornelissen, Anneleen; Cenens, William; Aertsen, Abram; Oliveira, Hugo; Azeredo, Joana; Verween, Gunther; Pirnay, Jean-Paul; Miller, Stefan; Volckaert, Guido

    2014-01-01

    ABSTRACT The global threat to public health posed by emerging multidrug-resistant bacteria in the past few years necessitates the development of novel approaches to combat bacterial infections. Endolysins encoded by bacterial viruses (or phages) represent one promising avenue of investigation. These enzyme-based antibacterials efficiently kill Gram-positive bacteria upon contact by specific cell wall hydrolysis. However, a major hurdle in their exploitation as antibacterials against Gram-negative pathogens is the impermeable lipopolysaccharide layer surrounding their cell wall. Therefore, we developed and optimized an approach to engineer these enzymes as outer membrane-penetrating endolysins (Artilysins), rendering them highly bactericidal against Gram-negative pathogens, including Pseudomonas aeruginosa and Acinetobacter baumannii. Artilysins combining a polycationic nonapeptide and a modular endolysin are able to kill these (multidrug-resistant) strains in vitro with a 4 to 5 log reduction within 30 min. We show that the activity of Artilysins can be further enhanced by the presence of a linker of increasing length between the peptide and endolysin or by a combination of both polycationic and hydrophobic/amphipathic peptides. Time-lapse microscopy confirmed the mode of action of polycationic Artilysins, showing that they pass the outer membrane to degrade the peptidoglycan with subsequent cell lysis. Artilysins are effective in vitro (human keratinocytes) and in vivo (Caenorhabditis elegans). PMID:24987094

  12. Exogenous lytic activity of SPN9CC endolysin against gram-negative bacteria.

    Science.gov (United States)

    Lim, Jeong-A; Shin, Hakdong; Heu, Sunggi; Ryu, Sangryeol

    2014-06-28

    Concerns over drug-resistant bacteria have stimulated interest in developing alternative methods to control bacterial infections. Endolysin, a phage-encoded enzyme that breaks down bacterial peptidoglycan at the terminal stage of the phage reproduction cycle, is reported to be effective for the control of bacterial pathogenic bacteria. Bioinformatic analysis of the SPN9CC bacteriophage genome revealed a gene that encodes an endolysin with a domain structure similar to those of the endolysins produced by the P1 and P22 coliphages. The SPN9CC endolysin was purified with a C-terminal oligo-histidine tag. The endolysin was relatively stable and active over a broad temperature range (from 24°C to 65°C). It showed maximal activity at 50°C, and its optimum pH range was from pH 7.5 to 8.5. The SPN9CC endolysin showed antimicrobial activity against only gram-negative bacteria and functioned by cutting the glycosidic bond of peptidoglycan. Interestingly, the SPN9CC endolysin could lyse intact gram-negative bacteria in the absence of EDTA as an outer membrane permeabilizer. The exogenous lytic activity of the SPN9CC endolysin makes it a potential therapeutic agent against gram-negative bacteria.

  13. Mars Global Reference Atmospheric Model 2000 Version (Mars-GRAM 2000): Users Guide

    Science.gov (United States)

    Justus, C. G.; James, B. F.

    2000-01-01

    This report presents Mars Global Reference Atmospheric Model 2000 Version (Mars-GRAM 2000) and its new features. All parameterizations for temperature, pressure, density, and winds versus height, latitude, longitude, time of day, and L(sub s) have been replaced by input data tables from NASA Ames Mars General Circulation Model (MGCM) for the surface through 80-km altitude and the University of Arizona Mars Thermospheric General Circulation Model (MTGCM) for 80 to 170 km. A modified Stewart thermospheric model is still used for higher altitudes and for dependence on solar activity. "Climate factors" to tune for agreement with GCM data are no longer needed. Adjustment of exospheric temperature is still an option. Consistent with observations from Mars Global Surveyor, a new longitude-dependent wave model is included with user input to specify waves having 1 to 3 wavelengths around the planet. A simplified perturbation model has been substituted for the earlier one. An input switch allows users to select either East or West longitude positive. This memorandum includes instructions on obtaining Mars-GRAM source code and data files and for running the program. It also provides sample input and output and an example for incorporating Mars-GRAM as an atmospheric subroutine in a trajectory code.

  14. Identification and Determination of Antibiotic Multiresistance of Gram-negative Bacteria Isolated from Hospital Sewage

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    Fatih Matyar

    2016-10-01

    Full Text Available In this study it was aimed to determine the microbial diversity and level of antibiotic resistance patterns of Gram-negative bacterial isolates from the hospital sewages. The 219 Gram-negative bacterial isolates to 16 different antibiotics (belonging 10 classes, was investigated by agar diffusion method. A total of 18 species of bacteria were isolated: the most common strains isolated from all samples were Klebsiella oxytoca (27.4%, Klebsiella pneumoniae (20.5% and Escherichia coli (20.1%. There was a high incidence of resistance to ampicillin (98.6%, streptomycin (95.9% and erythromycin (90.0%, and a low incidence of resistance to cefepim (13.2%, imipenem (5.0% and meropenem (3.2%. 35.6% of all bacteria isolated from hospital sewage were resistant to 9 different antibiotics. The multiple antibiotic resistances (MAR index ranged from 0.25 to 0.94. Results show that hospital sewages have a significant proportion of antibiotic resistant Gram-negative bacteria, and these bacteria constitute a potential risk for public health.

  15. Sensibilidad antimicrobiana de la microbiota ambiental de las unidades de cuidados intensivos de un hospital peruano

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    José Díaz-Tello

    Full Text Available Con el objetivo de detectar y determinar la sensibilidad antimicrobiana de bacilos Gram negativos y cocos Gram positivos aislados de la microbiota ambiental de los servicios de la Unidad de Cuidados Intensivos (UCI de Neonatología, de Pediatría y de la Unidad de trasplantes (renal, hepático y general en un hospital de Lima; se tomaron 80 muestras de superficies inanimadas usando hisopado húmedo. Se identificaron 61 cepas bacterianas que correspondieron a Staphylococcus epidermidis (46,0%, Alcaligenes sp. (21,3%, Pseudomonas aeruginosa (16,4%, Acinetobacter sp. (13,1% Staphylococcus aureus (1,6% y Staphylococcus haemolyticcus (1,6%. Acinetobacter y Pseudomonas aeruginosa mostraron una elevada sensibilidad a los antibióticos evaluados, en contraste Alcaligenes sp. y Staphylococcus epidermidis presentaron la mayor resistencia antimicrobiana. Staphylococcus epidermidis y Alcaligenes sp. fueron las bacterias que presentaron mayor resistencia a los antibióticos y las que mayormente se aislaron. Se recomienda recurrir a métodos de asepsia y monitoreo sostenidos en las UCI.

  16. A 980nm driven photothermal ablation of virulent and antibiotic resistant Gram-positive and Gram-negative bacteria strains using Prussian blue nanoparticles.

    Science.gov (United States)

    Maaoui, Houcem; Jijie, Roxana; Pan, Guo-Hui; Drider, Djamel; Caly, Delphine; Bouckaert, Julie; Dumitrascu, Nicoleta; Chtourou, Radouane; Szunerits, Sabine; Boukherroub, Rabah

    2016-10-15

    A 980nm laser-driven antimicrobial photothermal therapy using poly(vinylpyrrolidone) -coated Prussian Blue nanoparticles (PVP/PB NPs) is demonstrated. This approach allows an efficient eradication of a virulent strain of Gram-negative Escherichia coli (E. coli) associated with urinary tract infection as well as for the ablation of antibiotic resistant pathogens such as methicillin resistant Staphylococcus aureus (MRSA) and extended spectrum β-lactamase (ESBL) E. coli. Interestingly the 980nm irradiation exhibits minimal effect on mammalian cells up to a PVP/PB NPs concentration of 50μgmL(-1), while at this concentration bacteria are completely eradicated. This feature is certainly very promising for the selective targeting of bacteria over mammalian cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Diversidad bacteriana en un biorreactor de lecho fluidificado durante el tratamiento de agua contaminada con nafta Bacterial diversity in a fluidized bed bioreactor (FBR treating gasoline-contaminated groundwater

    Directory of Open Access Journals (Sweden)

    S. L. Ara-Rojas

    2007-12-01

    Full Text Available El objetivo principal de esta investigación fue determinar la diversidad bacteriana del proceso de biorremediación de agua contaminada con nafta en un biorreactor de lecho fluidificado en el Recinto Universitario de Mayagüez, de la Universidad de Puerto Rico. El aislamiento y la caracterización de las colonias bacterianas del sistema de biorremediación fueron realizados en medio R2A. Las pruebas morfológicas incluyeron la determinación de la morfología celular y de las colonias, y la reacción frente a la coloración de Gram. Las propiedades fisiológicas se determinaron usando el sistema Biolog® y sobre la base de la habilidad para desarrollar en medio mínimo con nafta como única fuente de carbono. La caracterización molecular se llevó a cabo por BOX-PCR y por análisis de secuencia del ADNr 16S mediante la técnica de ARDRA (amplified ribosomal DNA restriction analysis. De los 162 morfotipos de colonias aislados, 75% fueron bacilos gram-negativos, 19% bacilos gram-positivos, 5% cocos gram-negativos y 1% cocos gram-positivos. Según el análisis ARDRA, estos morfotipos se distribuyeron en 90 grupos genéticos, de los cuales 53% incluyeron cepas con crecimiento en nafta. Las 86 cepas que crecieron en nafta presentaron 52 patrones de amplificación, los que a través de BOX-PCR se agruparon en 50 grupos metabólicamente no relacionados. El alto nivel de diversidad microbiana observado en el reactor permitió la remoción del contaminante y, al parecer, fue importante para la operación estable y eficiente del sistema.The main objective of this research project was to determine the bacterial diversity during the process of bioremediation of water contaminated with gasoline in a fluidized bed reactor at Mayagüez, PR. Isolation and characterization of bacterial populations from the bioremediation system was performed on R2A medium. Morphological tests included cellular and colonial shape and reaction to Gram coloration. Physiological

  18. Lesões granulomatosas encontradas em bovinos abatidos para consumo

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    Bianca Tessele

    2014-08-01

    (bacilos gram-negativos e da actinomicose (bacilos gram-positivos pôde ser observado somente nas colorações de Gram. Os diagnósticos diferenciais para essas três condições são discutidos.

  19. Burdock (Arctium lappa Leaf Extracts Increase the In Vitro Antimicrobial Efficacy of Common Antibiotics on Gram-positive and Gram-negative Bacteria

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    Pirvu Lucia

    2017-04-01

    Full Text Available This work aimed to study the potential effects of four Arctii folium extracts, 5 mg gallic [GAE] acid equivalents per 1 mL sample, on six antibiotics (Ampicillin/AM, Tetracycline/TE, Ciprofloxacin/CIP, Sulfamethoxazole-Trimethoprim/SXT, Chloramphenicol/C and Gentamicin/CN tested on four Gram-positive (Staphylococcus aureus ATCC 6538, Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, and Staphylococcus epidermidis ATCC 12228 and five Gram-negative (Proteus mirabilis ATCC 29245, Escherichia coli ATCC 35218, E. coli ATCC 11229, E. coli ATCC 8739, and Bacillus cereus ATCC 11778 bacteria. Arctii folium extracts were the whole ethanol extract/W and subsequent ethyl acetate/EA, aqueous/AQ, and chloroform/CHL fractions. Chemical qualitative analysis (HPTLC method emphasized five main polyphenol compounds in Arctii folium polar extracts: chlorogenic acid (Rf≈0.52/0.55 and its isomer, 1,5-di-O-caffeoylquinic acid (Rf≈0.90/0.92, plus cynarin (Rf≈0.77, hyperoside (Rf≈0.68/0.64 and isoquercitrin (Rf≈0.69/0.71. Microbiological screening indicated Arctii folium polar extracts (AQ and W efficacy on S. epidermidis ATCC 12228; the MIC values were in the range of common antibiotics, being 32 and 128 μg GAE per mL sample respectively. The unpredictable effects (stimulatory or inhibitory of Arctii folium extracts in combination with typical antibiotics as well as a potential use of the whole ethanol extract/W for restoring the antimicrobial potency of susceptible antibiotics have also been evidenced.

  20. Differential regulation of polysaccharide-specific antibody responses to isolated polysaccharides, conjugate vaccines, and intact Gram-positive versus Gram-negative extracellular bacteria.

    Science.gov (United States)

    Snapper, Clifford M

    2016-06-24

    Bacterial capsular polysaccharides are major virulence factors and are key targets in a number of licensed anti-bacterial vaccines. Their major characteristics are their large molecular weight and expression of repeating antigenic epitopes that mediate multivalent B cell receptor cross-linking. In addition, since the majority of these antigens cannot associate with MHC-II they fail to recruit CD4+ T cell help and are referred to as T cell-independent antigens. In this review I will discuss a series of studies from my laboratory that have underscored the importance of understanding polysaccharide-specific antibody responses within the context in which the PS is expressed (i.e. in isolation, as a component of conjugate vaccines, and expressed naturally by intact bacteria). We have shown that multivalent B cell receptor crosslinking, as mediated by polysaccharides, uniquely determines the qualitative response of the B cell to subsequent stimuli, but by itself is insufficient to induce antibody secretion or class switching. For these latter events to occur, second signals must act in concert with primary signals derived from the B cell receptor. The co-expression of polysaccharide and protein within intact bacteria promotes recruitment of CD4+ T cell help for the associated PS-specific IgG response, in contrast to isolated polysaccharides. Further, the particulate nature of extracellular bacteria confers properties to the polysaccharide-specific IgG response that makes it distinct immunologically from soluble conjugate vaccines. Finally, the underlying biochemical and/or structural differences that distinguish Gram-positive and Gram-negative bacteria appear to play critical roles in differentially regulating the associated polysaccharide-specific IgG responses to these groups of pathogens. These studies have a number of implications for the understanding and future design of polysaccharide-based vaccines. Published by Elsevier Ltd.