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Sample records for aureus meticilino-resistentes aislados

  1. Aislamiento de Staphylococcus aureus meticilino resistente en abscesos de mama en una Maternidad Pública

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    Cristina Boccaccio

    2014-06-01

    Full Text Available La mastitis y los abscesos de mama representan un factor de riesgo para el abandono de la lactancia. Se incluyen dentro de las infecciones de piel y partes blandas y comparten los cambios epidemiológicos que llevan a replantear el tratamiento empírico inicial. Se estudiaron 137 casos de abscesos de mama desde enero de 2007 a diciembre de 2011. Se analizó incidencia, días postparto, factores de riesgo, datos microbiológicos y tratamiento antibiótico. Desde 2007a 2011 se observó un constante aumento de la incidencia de casos: 0.19 vs. 0.84% (p < 0.001. Días postparto de aparición del absceso 41.9 ± 35.8 días (Media ± DE, primiparidad 70.6%. Los factores de riesgo más frecuentemente encontrados fueron grietas del pezón e ingurgitación mamaria (95%. Staphylococcus aureus (SA fue el responsable de 82.3 a 95.0% de los abscesos según los años; la resistencia a oxacilina de las cepas de SA superó el 60%. Las cepas aisladas de SA meticilino resistentes (SAMR fueron sensibles a eritromicina clindamicina, gentamicina, rifampicina, ciprofloxacina y trimetroprima-sulfametoxasol en diferentes porcentajes según los años. Requirieron drenaje el 100% de los casos; en 60% el tratamiento empírico inicial fue inadecuado. Continuaron amamantando 90% de las madres. Estos datos enfatizan la necesidad de prevenir los factores de riesgo: grietas del pezón e ingurgitación mamaria. La modificación del tratamiento antibiótico inicial requiere el estudio bacteriológico de las infecciones de piel y partes blandas dado que la prevalencia de SAMR no es uniforme y varía en diferentes poblaciones y ubicaciones geográficas.

  2. Fagoterapia frente a infecciones por Staphylococcus aureus meticilino resistente en ratones

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    Jesús H Tamariz

    2014-03-01

    Full Text Available Objetivos: Evaluar la actividad de los bacteriófagos frente a infecciones localizadas y sistémicas producidas por Staphylococcus aureus resistente a meticilina (MRSA Materiales y métodos. Se realizó un estudio de tipo experimental en 45 ratones de la cepa Balb/c divididos en nueve grupos de cinco individuos. Se aislaron diez bacteriófagos nativos a partir de muestras clínicas y efluentes hospitalarios, se evaluó su capacidad lítica y su espectro de actividad, en base a lo cual se seleccionaron seis fagos para los ensayos de fagoterapia. Adicionalmente, se empleó un bacteriófago de origen comercial. La fagoterapia fue evaluada mediante profilaxis y terapia de infecciones localizadas y sistémicas causadas por la inoculación de MRSA por vía subcutánea y endovenosa respectivamente. Se probó la efectividad de tres esquemas terapéuticos: monoterapia, cóctel de fagos en múltiples dosis y de cóctel de fagos en una sola dosis. También se comparó la actividad terapéutica de los fagos frente a vancomicina y clindamicina. Resultados. El cóctel de fagos y la terapia a diversas dosis fueron efectivos para prevenir y controlar infecciones localizadas por MRSA, su actividad fue similar a la de vancomicina y clindamicina. La dosis única del cóctel de fagos no logró controlar la infección localizada; asimismo, la fagoterapia no resultó efectiva en infecciones sistémicas. Conclusiones. La fagoterapia se proyecta como una alternativa viable frente a infecciones causadas por MRSA. Se requieren estudios que evalúen aspectos relacionados con la inocuidad de los fagos frente al paciente

  3. Fagoterapia frente a infecciones por Staphylococcus aureus meticilino resistente en ratones

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    Jesús H Tamariz

    2014-01-01

    Full Text Available Objetivos: Evaluar la actividad de los bacteriófagos frente a infecciones localizadas y sistémicas producidas por Staphylococcus aureus resistente a meticilina (MRSA Materiales y métodos. Se realizó un estudio de tipo experimental en 45 ratones de la cepa Balb/c divididos en nueve grupos de cinco individuos. Se aislaron diez bacteriófagos nativos a partir de muestras clínicas y efluentes hospitalarios, se evaluó su capacidad lítica y su espectro de actividad, en base a lo cual se seleccionaron seis fagos para los ensayos de fagoterapia. Adicionalmente, se empleó un bacteriófago de origen comercial. La fagoterapia fue evaluada mediante profilaxis y terapia de infecciones localizadas y sistémicas causadas por la inoculación de MRSA por vía subcutánea y endovenosa respectivamente. Se probó la efectividad de tres esquemas terapéuticos: monoterapia, cóctel de fagos en múltiples dosis y de cóctel de fagos en una sola dosis. También se comparó la actividad terapéutica de los fagos frente a vancomicina y clindamicina. Resultados. El cóctel de fagos y la terapia a diversas dosis fueron efectivos para prevenir y controlar infecciones localizadas por MRSA, su actividad fue similar a la de vancomicina y clindamicina. La dosis única del cóctel de fagos no logró controlar la infección localizada; asimismo, la fagoterapia no resultó efectiva en infecciones sistémicas. Conclusiones. La fagoterapia se proyecta como una alternativa viable frente a infecciones causadas por MRSA. Se requieren estudios que evalúen aspectos relacionados con la inocuidad de los fagos frente al paciente

  4. Presentación atípica de piomiositis tropical difusa de psoas por Staphylococcus aureus meticilino resistente Atypical presentation of diffuse tropical pyomiositis of the psoas due to methicillin resistant Staphylococcus aureus

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    Ray Ticse; Weymar Melgarejo; Alfredo Fuentes-Dávila; Jesús Ortíz; Jaime Zegarra

    2012-01-01

    La piomiositis tropical difusa primaria es una enfermedad de presentación infrecuente en nuestro medio, con pocos casos asociados a Staphylococcus aureus meticilino resistente, adquirido en la comunidad (MRSA-AC). Se presenta el caso de un paciente de 70 años, con tratamiento irregular para diabetes mellitus tipo 2, que fue hospitalizado por presentar un cuadro de diez días de evolución, con dolor lumbar irradiado a miembro inferior izquierdo, fiebre y flexión forzada de la cadera derecha por...

  5. Enfermedad invasora por Staphylococcus aureus meticilino resistente adquirida en la comunidad Community-acquired methicillin-resistant Staphylococcus aureus disseminated disease

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    Clarisa Brezzo

    2006-10-01

    Full Text Available Se presenta un caso de enfermedad invasora por Staphylococcus aureus meticilino resistente (SAMR adquirido en la comunidad (SAMR-c. Paciente varón de 21 años, previamente sano, que consultó por nódulos subcutáneos compatibles con gomas. La ultrasonografía reveló múltiples abscesos subcutáneos e imágenes consistentes con piomiositis, además de derrame pleural y pericárdico. En el cultivo del material purulento obtenido por punción-aspiración con aguja fina de las lesiones se aisló S. aureus. El antibiograma por difusión mostró resistencia a cefalotina, eritromicina y clindamicina, y sensibilidad a trimetroprima-sulfametoxazol, ciprofloxacina y rifampicina. La meticilino resistencia se confirmó por aglutinación con partículas de látex sensibilizadas con anticuerpos monoclonales dirigidos contra la proteína ligadora de penicilina 2A. El paciente fue tratado con ciprofloxacina y rifampicina durante cuatro semanas, con evolución favorable. La frecuencia de infecciones por SAMR-c está en aumento, observándose en personas sin factores de riesgo aparentes. Esto llevaría a fracaso en el tratamiento empírico para infecciones de la comunidad en los que se presume etiología estafilocócica.A 21 year old man, previously healthy, presented with subcutaneous nodes consistent with gummas. Ultrasonography disclosed multiple subcutaneous abscesses and images suitable with piomiositis, pleural and pericardium effusion. A puncture-aspirate with fine-needle was performed and produced purulent material, with isolate of Staphylococcus aureus. Antimicrobial susceptibility testing by disk diffusion showed resistant to cefalotin, erythromycin and clindamycin, and susceptibility to trimethoprim-sulfamethoxazole, ciprofloxacin and rifampicin. Methicilin-resistance was confirmed by Staphyslide agglutination testing (Biomérieux. The patient was treated with ciprofloxacin and rifampicin during four weeks, with a good clinical response. The

  6. Presentación atípica de piomiositis tropical difusa de psoas por Staphylococcus aureus meticilino resistente Atypical presentation of diffuse tropical pyomiositis of the psoas due to methicillin resistant Staphylococcus aureus

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    Ray Ticse

    2012-03-01

    Full Text Available La piomiositis tropical difusa primaria es una enfermedad de presentación infrecuente en nuestro medio, con pocos casos asociados a Staphylococcus aureus meticilino resistente, adquirido en la comunidad (MRSA-AC. Se presenta el caso de un paciente de 70 años, con tratamiento irregular para diabetes mellitus tipo 2, que fue hospitalizado por presentar un cuadro de diez días de evolución, con dolor lumbar irradiado a miembro inferior izquierdo, fiebre y flexión forzada de la cadera derecha por dolor a la movilización. El diagnóstico de piomiositis difusa de ambos psoas se realizó con resonancia magnética. Del cultivo de una colección paravertebral posterior se aisló Staphylococcus aureus resistente a oxacilina, penicilina y dicloxacilina.Diffuse tropical primary pyomyositis is an infrequent entity in our country, with few cases associated to communityacquired Methicillin- resistant Staphylococcus aureus. There are no reported cases of Community-Acquired Methicillin- Resistant Staphylococcus aureus (CA- MRSA in Peru. We present the case of a 70 year old male with a previous diagnosis of type 2 diabetes mellitus, receiving irregular treatment, who was admitted to the hospital with a history of 10 days of low back pain radiating to the left leg, fever and forced flexion of the right hip due to pain during movement. The diagnosis of diffuse pyomyositis of both psoas muscles was performed with MRI and culture of a posterior paravertebral collection, from which Staphylococcus aureus resistant to oxacillin, penicillin and dicloxacillin was isolated.

  7. Evaluación de cuatro métodos para la detección de Staphylococcus aureus meticilino-resistente de muestras clínicas en un hospital regional Evaluation of four methods for detecting methicillin-resistant Staphylococcus aureus isolates from clinical specimens at a regional hospital in Mexico

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    Gabriel Acosta-Pérez

    2012-02-01

    Full Text Available OBJETIVO: Investigar la prevalencia de Staphylococcus aureus meticilino-resistente (MRSA en aislados clínicos y determinar la concordancia entre los métodos de detección de MRSA en un laboratorio con recursos y personal limitado. MATERIAL Y MÉTODOS: Se analizaron 140 cepas de Staphylococcus aureus aisladas de muestras clínicas de diferentes departamentos mediante pruebas convencionales: producción de β-lactamasa, sensibilidad a oxacilina con MIC-Vitek 2-XL, ChromID MRSA, difusión en agar para discos de 30 μg de cefoxitina, detección de PBP2a y PCR para el gen mecA. Se determinó el índice kappa de Cohen, para evaluar la concordancia entre los diferentes métodos utilizados. RESULTADOS: La prevalencia encontrada fue de 90.7%. La sensibilidad y especificidad para los diferentes métodos de detección fue: difusión en disco para cefoxitina 97 y 92% respectivamente, MIC Vitek 2-XL 97 y 69%, ChromoID MRSA 97 y 85% y detección de PBP2a 98 y 100%. CONCLUSIONES: Todos los métodos son muy buenos para la detección de MRSA; la elección en el uso de cada método dependerá de la infraestructura de cada laboratorio.OBJETIVE: To estimate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA in clinical isolates and to compare different methods for detection of MRSA in a lab with limited available personnel and resources. MATERIAL AND METHODS: 140 Staphylococcus aureus strains isolated from patients in several departments were assayed for β-lactamase production, MIC-Vitek 2 oxacillin, ChromID MRSA, disk diffusion in agar for cefoxitin 30 μg and PBP2a detection. The results of conventional tests were compared with the "gold standard" PCR test for mecA gene. Cohen´s kappa index was also calculated in order to evaluate the intra assay agreement between the used methods. RESULTS: The found prevalence was 90.7%. Sensitivity and specificity were: disk diffusion for cefoxitin 97 and 92% respectively, MIC Vitek 2-XL 97 and 69%, Chromo

  8. Staphylococcus aureus meticilino resistente adquirido na comunidade: um problema mundial

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    Síntia de Souza Evangelista

    2015-02-01

    Full Text Available Objetivo: descrever a epidemiologia dos casos de CA-MRSA no Brasil de forma a compreender sua ocorrência, fatores de risco associados e formas de manejo em relação à situação mundial. Método: revisão integrativa e para seleção dos estudos utilizou-se as bases de dados: Scopus, Science direct, Isi Web of Knowledge, PUBMED e BVS. Resultados: foram identificados dez artigos nacionais que descreveram 21 casos de CA-MRSA principalmente em crianças, adolescentes e adultos com quadro de infecção de pele e tecidos moles evoluindo para infecções graves relacionados ao clone Oceania Southwest Pacific Clone (OSPC que resultaram em hospitalização. Conclusão: apesar do CA-MRSA ser considerado um micro-organismo de relevância mundial verificou-se a escassez de dados publicados sobre sua epidemiologia no Brasil, o que dificultam o delineamento da realidade do país frente ao CA-MRSA.

  9. Estudio de actinomicetos marinos aislados de la costa central del Perú y su actividad antibacteriana frente a Staphylococcus aureus Meticilina Resistentes y Enterococcus faecalis Vancomicina Resistentes Study of marine actinomycetes isolated from the central coast of Peru and their antibacterial activity against Methicillin-Resistant Staphylococcus aureus and Vancomycin-Resistant Enterococcus faecalis

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    Jorge León

    2011-06-01

    Full Text Available Objetivos. Determinar el potencial antimicrobiano de actinomicetos marinos frente a cepas S. aureus meticilino-resistentes (MRSA y E. faecalis vancomicina-resistentes (VRE. Materiales y métodos. En dos medios de cultivo se sembraron 29 cepas de actinomicetos aislados de sedimento marino. Se evaluó la capacidad inhibitoria mediante pruebas de antagonismo in vitro para MRSA y VRE. Se procesó los extractos orgánicos de tres actinomicetos seleccionados para determinar la Concentración Mínima Inhibitoria (CMI del compuesto activo. Resultados. La mayoría de los actinomicetos aislados correspondieron a un grupo homogéneo de blanco-grisáceos (62% con buen nivel de crecimiento en agar marino. Los porcentajes inhibitorios fueron superiores a 85% para ambos patógenos con halos de inhibición mayores a 69 y 78 mm de diámetro para MRSA y VRE respectivamente. Los extractos diclorometánicos de tres de los actinomicetos aislados (I-400A, B1-T61, M10-77 mostraron gran potencial inhibitorio de ambos patógenos, siendo M10-77 la cepa de actinomiceto de mayor actividad antibiótica frente a S. aureus ATCC 43300 resistente a meticilina y E. faecalis ATCC 51299 resistente a vancomicina con una Concentración Mínima Inhibitoria (CMI de 7,9 y 31,7 μg/ mL respectivamente. El análisis filogenético de la cepa M10- 77 presenta un 99% de similaridad con la especie marina Streptomyces erythrogriseus. Conclusiones. El sedimento marino de la costa central del Perú es fuente promisorio de cepas de actinomicetos con gran capacidad de producir compuestos bioactivos capaces de inhibir patógenos tipificados como multidrogo-resistentes tales como S. aureus meticilino resistentes y E. faecalis vancomicina resistentes.Objectives. To determine the antimicrobial potential of marine actinomycetes against drug-resistant pathogens represented by strains of methicillin-resistant Staphylococcus aureus (MRSA and vancomycin-resistant Enterococcus faecalis (VRE. Materials and

  10. Aislamiento de Staphylococcus aureus meticilino resistente en abscesos de mama en una Maternidad Pública

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    Cristina Boccaccio; Virginia Verdaguer Babic; Liliana Botto; María M Cervetto; Silvia Cetani; Silvina Paladino; Roxana Conti; Antonio Lanzillota; Rosa Herrera; Dora Amarante

    2014-01-01

    La mastitis y los abscesos de mama representan un factor de riesgo para el abandono de la lactancia. Se incluyen dentro de las infecciones de piel y partes blandas y comparten los cambios epidemiológicos que llevan a replantear el tratamiento empírico inicial. Se estudiaron 137 casos de abscesos de mama desde enero de 2007 a diciembre de 2011. Se analizó incidencia, días postparto, factores de riesgo, datos microbiológicos y tratamiento antibiótico. Desde 2007a 2011 se observó un constante au...

  11. Patrones de susceptibilidad antimicrobiana de aislados clínicos de Staphylococcus aureus procedentes de la comunidad

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    Estrella Alvarez Varela

    2008-01-01

    Full Text Available Se estudió la resistencia antimicrobiana de 695 aislamientos clínicos de Staphylococcus aureus procedentes de infecciones de las vías respiratorias superiores, lesiones en piel, secreciones de heridas, exudados conjuntivales, óticos y sistema genitourinario de pacientes atendidos en consulta externa de cinco hospitales pediátricos, ubicados en diferentes ciudades y regiones de Cuba durante el período enero de 2002 a diciembre de 2004. Los datos fueron obtenidos por el Sistema DIRAMIC y procesados por el sistema de programas para la confección de Mapas Microbianos, versión 6.0. Los antibióticos probados fueron: penicilina G, oxacilina, cefazolina, gentamicina, amicacina, tetraciclina, cloranfenicol, eritromicina, ciprofloxacina y sulfametoxazol + trimetoprim. Los aislados fueron clasificados sobre la base de su resistencia a la oxacilina. De ellos, 118 (17,0 % fueron resistentes al fármaco (Staphylococcus aureus meticilina resistente, SAMR y 577 (83,0 % sensibles (Staphylococcus aureus meticilina sensible, SAMS. Se observó un incremento significativo de las cepas SAMR en el período y de la resistencia dentro de este grupo al resto de los antibióticos probados, aunque más del 50 % de los aislados conservan la susceptibilidad a macrólidos, aminoglucósidos y quinolonas. Por su parte, los porcentajes de resistencia de las cepas sensibles fueron bajos y muy similares en los tres años para la mayoría de los antibióticos ensayados, con excepción de eritromicina y ciprofloxacina, para los que se observaron incrementos en el año 2004. Los resultados revelaron que en Cuba los Staphylococcus aureus resistentes a oxacilina aún no son un problema. Pero la aparición de este germen en la comunidad en una frecuencia cercana al 20 %, hace necesario mantener la vigilancia de este fenómeno, lo cual permitirá tomar a tiempo las medidas pertinentes para evitar sus consecuencias negativas.

  12. Perfil fenotípico e genotípico de Staphylococcus aureus isolados de estudantes de enfermagem, 2008 Perfil fenotípico y genotípico del Staphylococcus aureus aislados de estudiantes de enfermería, 2008 Phenotypic and genotypic profile of Staphylococcus aureus isolated in nursing students, 2008

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    Suelen Teixeira Faria

    2011-01-01

    Full Text Available OBJETIVO: Verificar a prevalência de carreamento nasal, perfil fenotípico e genotípico de S. aureus isolados de estudantes de enfermagem. MÉTODOS: Estudo transversal, com população composta por 101 alunos, cursando as três primeiras séries do curso de graduação em Enfermagem no ano de 2008. S. aureus foi isolado de material biológico obtido dos vestíbulos nasais através de swab. A susceptibilidade à oxacilina e vancomicina foi determinada pelo teste de concentração inibitória mínima. A presença do gene MecA foi determinada pelo teste de reação em cadeia da polimerase. RESULTADOS: Verificou-se 90,1% de positividade para S. aureus. A frequência de resistência à oxacilina foi de 9,8% e todas as amostras foram sensíveis à vancomicina. A oito amostras resistentes À oxacilina apresentaram o gene MecA. CONCLUSÃO: A prevalência foi elevada. A resistência à oxacilna foi expressiva e todas as amostras foram sensíveis à vancomicina. As amostras resistentes à oxacilina carreavam o gene MecA.OBJETIVO: Verificar la prevalencia de transporte nasal, perfil fenotípico y genotípico de S. aureus aislados de estudiantes de enfermería. MÉTODOS: Estudio transversal, con población compuesta por 101 alumnos, cursando las tres primeras series del Pregrado en Enfermería en el año 2008. El S. aureus fue aislado del material biológico obtenido de los vestíbulos nasales a través de swab. La susceptibilidad a la oxacilina y vancomicina fue determinada por el test de concentración inhibitoria mínima. La presencia del gen MecA fue determinada por el test de reacción en cadena de la polimerasa. RESULTADOS: Se verificó el 90,1% de positividad para el S. aureus. La frecuencia de resistencia a la oxacilina fue de 9,8% y todas las muestras fueron sensibles a la vancomicina. Las ocho muestras resistentes a la oxacilina presentaron el gen MecA. CONCLUSION: La prevalencia fue elevada. La resistencia a la oxacilina fue expresiva y todas

  13. Caracterización del gen mecA de Staphylococcus aureus resistentes a meticilina aislados de tres grupos poblacionales de la ciudad de Medellín

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    Marcela Sanchez; Orville Hernández; Luz Astrid Velasquez; Dora Rivas; Alejandra Marín; Leonel Andrés González; Clara Duque

    2013-01-01

    Introducción: Staphylococcus aureus resistente a la meticilina (SARM) es responsable de infecciones intrahospitalarias, las que constituyen una importante causa de morbilidad y mortalidad en nuestro medio, por lo cual la rápida identificación y tipificación molecular de la resistencia como el complejo SSCmec es esencial para entender la epidemiología de la infección. Objetivo: Caracterizar fenotípicamente la resistencia a meticilina y genotípicamente el casete cromosomal SSCmec en cepas de S....

  14. Frecuencia de genes que codifican factores de virulencia en Staphylococcus aureus aislados de niños que concurrieron al Hospital General Pediátrico Niños de Acosta Ñú, durante el año 2010

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    Fatima Rodríguez Acosta

    2015-04-01

    Full Text Available Staphylococcus aureus es un microorganismo con habilidad de infectar diferentes tejidos celulares, por portar genes que le confieren resistencia a antibióticos, factores de virulencia y su plasticidad genética, que podrían contribuir a una progresión rápida y complicada de la enfermedad. El Paraguay no cuenta con datos epidemiológicos que indiquen los factores de virulencia que presentan las cepas de S. aureus, por lo que el objetivo del trabajo fue determinar un perfil de virulencia detectando los genes codificantes de: hemolisinas α y β, enterotoxinas A, B, C, D, H y toxinas exfoliativas A y B. Este estudio observacional descriptivo de corte transverso, con muestreo no probabilístico de casos consecutivos, incluyó 50 aislados de S. aureus obtenidos a partir de muestras clínicas de secreciones de piel, partes blandas o líquidos corporales de pacientes menores de 17 años que concurrieron al Hospital General Pediátrico Niños de Acosta Ñú durante el año 2.010. Las reacciones de PCR incluyeron la detección de los genes: sea+seb+sec+ADNr16S, hlA+hlB, eta+etb, sed y seh. El 82% de los aislados provenía de niños que presentaron cuadros clínicos compatibles con infecciones de piel y partes blandas y el 18% de cuadros clínicos graves como sepsis, osteomielitis y neumonías. Los aislados contaban con datos de portación de Leucocidina de Panton-Valentine, el cual fue el factor de virulencia más frecuentemente detectado (58%, seguido de las hemolisinas alfa (16% y beta (8%. Las enterotoxinas y las toxinas exfoliativas fueron menos frecuentes (0-2%, y no se detectaron genes codificantes de las enterotoxinas C y D.

  15. Caracterización microbiológica y molecular de Staphylococcus aureus resistente a meticilina (SARM) aislado de muestras de alimentos de origen cárnico en la ciudad de Cartagena

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    López Gutiérrez, Lersy Ana

    2013-01-01

    Resumen: Staphylococcus aureus es un microorganismo que posee características particulares de virulencia y resistencia a los antibióticos. En los humanos causa una amplia variedad de enfermedades infecciosas. El principal impacto de este microorganismo se debe a las cepas de Staphylococcus aureus resistentes a la Meticilina (SARM), que tradicionalmente se encontraban limitadas al ámbito hospitalario,produciendo infecciones nosocomiales a nivel mundial. Sin embargo, en años recientes las cepas...

  16. In vitro bactericidal activity of equine platelet concentrates, platelet poor plasma, and plasma against methicillin-resistant Staphylococcus aureus Actividad bactericida in vitro de concentrados de plaquetas, plasma pobre en plaquetas y plasma de equinos contra Staphylococcus aureus resistente a la meticilina

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    ME Álvarez

    2011-01-01

    Full Text Available The aims of the study were 1 to evaluate the antibacterial effect of equine platelet concentrates (ePCs (either activated or not with calcium gluconate (CG against methicillin-resistant Staphylococcus aureus (MRSA, and 2 to compare their antibacterial effect with activated platelet poor plasma (PPP and plasma (P. Blood products were allotted in 4 groups (ePC, ePC/CG, PPP/CG, and P plus a positive control group (PCG and a negative control group, and mixed with MRSA and Mueller-Hinton broth. Samples were incubated during 1, 4, 8, 12, and 24 h, and colony-forming units were counted. The bacterial growth was significantly (P = 0.01 inhibited by the ePC, ePC/CG, PPP/CG and P in comparison with the PCG during the first 12 h. At 24h only a statistically significant (P = 0.01 antibacterial effect was noticed for the ePC, ePC/ CG and PPP/CG in comparison with the PCG and P. Equine PCs and PPP provided the best in vitro antibacterial effect against MRSA.Los objetivos del estudio fueron: 1 evaluar el efecto antibacteriano de concentrados de plaquetas equinas (ePC (activados o no con gluconato de calcio (CG frente a Staphylococcus aureus meticilino-resistente (MRSA y 2 comparar su efecto antibacteriano contra plasma pobre en plaquetas (PPP (activado con CG -PPP/GC- y plasma (P. Los productos sanguíneos fueron divididos en 4 grupos (ePC, ePC/CG, PPP/CG y P, más un grupo control positivo (PCG y otro control negativo. Los grupos se mezclaron con caldo Mueller-Hinton y MRSA. Las muestras fueron incubadas durante 1, 4, 8, 12 y 24 horas y se contaron las unidades formadoras de colonias. El crecimiento de las bacterias fue significativamente (P = 0,01 inhibido por el ePC, ePC/CG, PPP/CG y P en comparación con el PCG durante las primeras 12 h. Sólo a las 24 horas hubo una diferencia estadísticamente significativa (P = 0.01 y se observó un efecto antibacteriano para el ePC, ePC/CG y PPP/CG en comparación con el PCG y P. Los ePCs y PPP equinos mostraron el

  17. Portadores nasales de sthaphylococcus aereus meticilino resistente en contacto con pacientes pediátricos con enfermedad diseminada adquirida en la comunidad.

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    Luis Miguel Sosa Ávila

    2007-11-01

    Full Text Available Background: sthaphylococcus aereus (SA is an important cause of disese in pediatric population. Methicillin resistant sthaphylococcus aereus (MRSA infection have spread worldwide coth health care and comunity setting. Asyntimatic colonization with MRSA has been described as a risk factor for subsequent MRSA infection. we determinate the rate of SA and MRSA colonization in contacts of pediatric patients with MRSA disseminated disease. Method: nasal sample of SA culture, sociodemographic and risk factor date were obtained from 57 contacts of four pediatric patients. SA isolated was tested for oxacilin anda antimicrobial susceptibility and penicillin binding protein 2α (PBP2α. Results: SA and MRSA rate colonization is 38.59% and 10.25% respectively. Sa colonization was higer in parents, brother and worker. MRSA colozation was higer in parents and brother, female, and people older 50 yerars. community acquired MRSA colonization is 3.51%. conclusions: Many contacts of pediatric patient with SA disseminated disease are colonized with SA and MRSA.

  18. Bacteriemia en pacientes internados con celulitis

    Directory of Open Access Journals (Sweden)

    Juan S. Lasa

    2012-08-01

    Full Text Available La celulitis es una inflamación aguda de la dermis y tejido celular subcutáneo de causa bacteriana, que generalmente complica a heridas, úlceras y dermatosis, aunque de manera frecuente no existe sitio de entrada. Se recomienda la realización de cultivo de punción de piel y partes blandas (PPB. Los hemocultivos raramente dan resultados positivos. El objetivo de este trabajo fue determinar la prevalencia de bacteriemia en pacientes internados en nuestra institución con diagnóstico de celulitis. Se analizaron retrospectivamente los registros clínicos de los pacientes con este diagnóstico al ingreso entre junio de 2007 y marzo de 2010. Se evaluaron los datos poblacionales, presencia de comorbilidades, y resultados de los cultivos. En ese período, se internaron 140 pacientes con diagnóstico de celulitis y a todos ellos se les realizó hemocultivo y cultivos de PPB. Setenta y cuatro eran varones (52.8%. La edad promedio: 47.5 ± 19.7 años (rango 16-94. El 40% tuvo cultivos positivos de PPB, en los que el Staphylococcus aureus meticilino resistente (SAMR fue el germen más frecuentemente aislado (35.7%; la prevalencia de bacteriemia fue del 8.6%, en donde el germen más frecuente fue Streptoccocus Beta hemolítico, grupo G (33% del total de hemocultivos positivos. La bacteriemia se asoció significativamente a mayor estadía hospitalaria (10.5 ± 8.9 vs. 4.9 ± 6, p = 0.004. Se asoció con mayor riesgo de hemocultivo positivo a ser diabético, tener cultivo de PPB positivo, consumo de alcohol y/o enfermedad pulmonar obstructiva crónica.

  19. Frecuencia de genes que codifican factores de virulencia en Staphylococcus aureus aislados de niños que concurrieron al Hospital General Pediátrico Niños de Acosta Ñú, durante el año 2010

    OpenAIRE

    Fatima Rodríguez Acosta; L Carpinelli; W Basualdo; Castro, H.; B Quiñonez; Argüello, R.; Rosa María Guillén Fretes

    2015-01-01

    Staphylococcus aureus es un microorganismo con habilidad de infectar diferentes tejidos celulares, por portar genes que le confieren resistencia a antibióticos, factores de virulencia y su plasticidad genética, que podrían contribuir a una progresión rápida y complicada de la enfermedad. El Paraguay no cuenta con datos epidemiológicos que indiquen los factores de virulencia que presentan las cepas de S. aureus, por lo que el objetivo del trabajo fue determinar un perfil de virulencia detectan...

  20. Prevalencia y perfil de resistencia a betalactámicos en estafilococos de perros y gatos Prevalence and resistance profile to beta-lactam antibiotics in staphylococci from dogs and cats

    Directory of Open Access Journals (Sweden)

    G Denamiel

    2009-12-01

    Full Text Available El objetivo de este trabajo fue conocer la prevalencia de especies y perfil de resistencia a betalactámicos en estafilococos aislados de infecciones en caninos y felinos. En perros, de 207 aislamientos, el porcentaje de las especies identificadas fue: S. intermedius 29,5%, S. aureus y S. simulans 20,8%, S. saprophyticus 12,6%, S. chromogenes 10,6%, S. haemolyticus 3,9% y S. epidermidis 1,9%. De 63 aislamientos en gatos: S. simulans 33,3%, S. intermedius y S. aureus 15,4%, S. saprophyticus 11,1%, S. haemolyticus 6,34%, S. chromogenes y S. epidermidis 3,5%. En perros, el porcentaje de resistencia a penicilina fue: S. intermedius 47,5%, S. aureus 34,8% y S. saprophyticus 7,7%. Los aislamientos que expresaron meticilina resistencia correspondieron: S. intermedius 9,8% y S. saprophyticus 3,8%. En gatos los estafilococos resistentes a penicilina fueron S. saprophyticus 42,8%, S. aureus y S. intermedius 15,4% y S. simulans 9,5%. No se hallaron especies de estafilococos meticilino resistentes.The purpose of this study was to characterize the prevalence and resistance profile to betalactam antibiotics of staphylococci isolated from canine and feline infections. Staphylococci were isolated from 207 dog samples. The species frequency for identified staphylococci were: S. intermedius 29.5%, S. aureus and S. simulans 20.8%, S. saprophyticus 12.6%, S. chromogenes 10.6%, S. haemolyticus 3.9% and S. epidermidis 1.9%. Sixty three staphylococci isolates were from cats: S. simulans 33.3%, S. intermedius and S. aureus 15.4%, S. saprophyticus 11.1%, S. haemolyticus 6.34%, S. chromogenes and S. epidermidis 3.5%. Resistance to penicillin in samples from dogs were: S. intermedius 47.5%, S. aureus 34.8% and S. saprophyticus 7.7%. Methicillin-resistance was evidenced in S. intermedius 9.8% and S. saprophyticus 3.8%. In samples from cats, penicillin-resistant staphylococci were: S. saprophyticus 42.8%, S. aureus and S. intermedius 15.4% and S. simulans 9

  1. Actividad fibrolítica de hongos ruminales aislados de ecosistemas tropicales

    OpenAIRE

    Gualdrón Duarte, Laura; Mayorga, O; Rodríguez, Diego Alberto; Manovacía, Patricia; Martín, Alejandro; Carulla Fornaguera, Juan Evangelista; Barahona, Rolando

    2009-01-01

    Se evaluó la capacidad de degradación de sustratos altamente fibrosos por 18 aislados fungales ruminales en fermentaciones de 120 horas utilizando como única fuente de carbono pasto colosuana (Bothriochloa pertusa). Dentro del ensayo se incluyeron aislados pertenecientes a los géneros Neocallimastix, Orpinomyces y Piromyces. De acuerdo con los parámetros del modelo de Gompertz, la fase de adaptación de los aislados fue de 23,8 horas (h) ± 4,20, con una producción de gas promedio de 195 ml/g s...

  2. Resistencia y susceptibilidad de microorganismos aislados en pacientes atendidos en una institución hospitalaria de tercer nivel, Villavicencio-Colombia, 2012

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    Oscar Alexander Gutiérrez Lesmes

    2015-05-01

    Full Text Available Introducción: La resistencia bacteriana es problema significativo de salud pública y está asociada al uso indiscriminado e irracional de antibióticos, lo que afecta la eficacia de los tratamientos. Objetivo: Estimar la resistencia antimicrobiana a los antibióticos resultado de las pruebas invitro de susceptibilidad en una institución hospitalaria de tercer nivel de Villavicencio, Colombia. Materiales y Métodos: Se realizó un estudio observacional, descriptivo de tipo retrospectivo, análisis univariado, calculando medias de las variables susceptibilidad, resistencia, antibiótico, microorganismos, y tipo de muestra resultados de las pruebas de susceptibilidad realizadas mediante técnica de Kirby-Bauer de 485 pruebas de susceptibilidad de la institución hospitalaria. Resultados y Discusión: Los microorganismos más frecuentemente aislados, fueron: Escherichia coli, Klebsiella pneumoniae ss. Pneumoniae, Staphylococcus aureus ss. Aureus representando el 49% de total de microorganismos, los mayores reportes de resistencia en la pruebas invitro las presentaron Serratia marcescens, Staphylococcus saprophyticus ss. Saprophytic, Enterobacter cloacae, presentan una resistencia media superior al 50%, y una susceptibilidad inferior 40%, la mayor resistencia media se presentó para los siguientes antibióticos, Cefalotina 72,2%, Cefazolina 59,9%, Nitrofurantoina 54,4%, Ceftriaxona 52,7%. Conclusiones: Antibióticos como la Cefalotina, Nitrofurantoina, Cefazolina y Ceftriaxona  pierden su utilidad terapéutica dada la elevada resistencia demostrada por los microorganismos aislados en las pruebas invitro, es necesario reforzar las medidas de uso adecuado de antibióticos para disminuir la posibilidad de adaptación y resistencia a los mismos,  el fenómeno de resistencia bacteriana ocurre fuera del ámbito hospitalario evidenciando la necesidad de iniciar también control y vigilancia en infecciones ocurridas en la comunidad.Cómo citar este

  3. CARACTERIZACIÓN FENOTÍPICA DE AISLADOS DE RIZOBIOS PROCEDENTES DE LA LEGUMINOSA FORRAJERA Canavalia ensiformis

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    Ionel Hernández Forte

    2012-01-01

    Full Text Available El objetivo del presente trabajo fue caracterizar fenotípicamente aislados de rizobios procedentes de la leguminosa forrajera Canavalia ensiformis. Se caracterizaron doce aislados, cinco posibles miembros del género Rhizobium/ Sinorhizobium, siete posibles integrantes del género Bradyrhizobium y dos cepas comerciales, BR 2001 y BR 2003a. Para la caracterización fenotípica de los aislados bacterianos se estudió su capacidad de utilizar seis fuentes de carbono, la tolerancia a condiciones de acidez y a diferentes niveles de cloruro de sodio (NaCl, la resistencia a seis antibióticos así como su crecimiento en tres temperaturas de incubación. Se determinó además la capacidad de estos aislados de producir polihidroxibutiratos (PHB. Todos los aislados estudiados utilizaron la lactosa, glucosa y manitol como fuentes de carbono. Uno de los aislados de rápido crecimiento resultó el más tolerante a pH 4.5. Los aislados posibles miembros del género Rhizobium/ Sinorhizobium toleraron una mayor concentración de NaCl que los posibles integrantes del género Bradyrhizobium. Tres de los aislados de rápido crecimiento fueron resistentes a los seis antibióticos utilizados. Cuando los aislados fueron incubados a 370C todos, con excepción del el aislado CP3 y la cepa comercial BR 2001, presentaron un crecimiento similar al control. El aislado CP10, de lento crecimiento, tuvo la capacidad de producir las mayores concentraciones de PHB (0.023 g.L-1.

  4. Benzoquinona e hidroquinona preniladas y otros constituyentes aislados de piper bogotense c. dc.

    OpenAIRE

    Peña, Luz Angela; Avella, Eliseo; Puentes de Díaz, Aura María

    2010-01-01

    Dos compuestos, que innovan la química conocida del género Piper, (2'E,6'E)-2- famesilhidroquinona, (2'E,6'E)-2-famesil- 1,4-benzoquinona, y a-D-glucosa fueron aislados de los frutos de Piper bogotense C. DC; los tallos y las hojas presentaron, como constimyentes mayoritarios, lactama del ácido 10-amino-4-hidroxi-2,3-dimetoxifenantreno carboxílico, 1,2-metilendioxi- 6-metil-4H-dibenzo lde,g] quinolina- ,5(6H)-diona (Cefaradiona A), estigmasterol y sitosterol. Adicionalmente de las ho...

  5. Benzoquinona e hidroquinona preniladas y otros constituyentes aislados de Piper Bogotense C. DC.

    OpenAIRE

    Luz Angela Peña; Eliseo Avella; Aura María Puentes de Díaz

    2010-01-01

    Dos compuestos, que innovan la química conocida del género Piper, (2'E,6'E)-2- famesilhidroquinona, (2'E,6'E)-2-famesil- 1,4-benzoquinona, y a-D-glucosa fueron aislados de los frutos de Piper bogotense C. DC; los tallos y las hojas presentaron, como constimyentes mayoritarios, lactama del ácido 10-amino-4-hidroxi-2,3-dimetoxifenantreno carboxílico, 1,2-metilendioxi- 6-metil-4H-dibenzo lde,g] quinolina- ,5(6H)-diona (Cefaradiona A), estigmasterol y sitosterol. Adicionalmente de las ho...

  6. Actividad antiinflamatoria de d-amirona y 4, 7-dimetoxiapigenina aislados de alnus acuminata

    OpenAIRE

    Salama, Ahmed; Avendaño, Inés Yamile

    2009-01-01

    El presente trabajo determinó el efecto antiinflamatorio de d-amirona (olean-13(18)-en-3-ona) y 4',7-dimetoxiapigenina (5-hidroxi-4¢,7-dimetoxiflavona), aislados de Alnus acuminata (Betulaceae), por el método del edema plantar en ratas hembra, en dosis de 30, 60 y 100 mg/kg y de 30, 60 y 80 mg/kg respectivamente. Ambas sustancias mostraron una actividad antiinflamatoria significativa. El efecto más alto de d-amirona se presentó a la primera hora en las tres dosis ensayadas comparable con el e...

  7. Staphylococcus aureus and Pregnancy

    Science.gov (United States)

    Staphylococcus aureus and Pregnancy In every pregnancy, a woman starts out with a 3-5% chance of ... risk. This sheet talks about whether exposure to staphylococcus aureus may increase the risk for birth defects ...

  8. Staphylococcus aureus toxins

    OpenAIRE

    Otto, Michael

    2013-01-01

    Staphylococcus aureus is a dangerous pathogen that causes a variety of severe diseases. The virulence of S. aureus is defined by a large repertoire of virulence factors, among which secreted toxins play a preeminent role. Many S. aureus toxins damage biological membranes, leading to cell death. In particular, S. aureus produces potent hemolysins and leukotoxins. Among the latter, some were recently identified to lyse neutrophils after ingestion, representing an especially powerful weapon agai...

  9. Portación nasal de Staphylococcus aureus en individuos de la comunidad: factores epidemiológicos

    OpenAIRE

    Sonia Fosch; Cristian Yones; Marta Trossero; Omar Grosso; Andrea Nepote

    2012-01-01

    La portación nasal de Staphylococcus aureus (SAU) en individuos sanos confirma su diseminación, constituye una fuente potencial de infección y se la relaciona con patologías atópicas. El objetivo del trabajo fue determinar la prevalencia de colonización nasal de SAU en individuos de la comunidad, sus respectivos patrones de resistencia antimicrobiana (PRA) y su asociación con factores epidemiológicos. Se realizó un estudio en 150 hisopados nasales. Se identificaron los aislados de SAU por mét...

  10. Bacteriemia en pacientes internados con celulitis Bacteremia in patients hospitalized with cellulitis

    Directory of Open Access Journals (Sweden)

    Juan S. Lasa

    2012-08-01

    Full Text Available La celulitis es una inflamación aguda de la dermis y tejido celular subcutáneo de causa bacteriana, que generalmente complica a heridas, úlceras y dermatosis, aunque de manera frecuente no existe sitio de entrada. Se recomienda la realización de cultivo de punción de piel y partes blandas (PPB. Los hemocultivos raramente dan resultados positivos. El objetivo de este trabajo fue determinar la prevalencia de bacteriemia en pacientes internados en nuestra institución con diagnóstico de celulitis. Se analizaron retrospectivamente los registros clínicos de los pacientes con este diagnóstico al ingreso entre junio de 2007 y marzo de 2010. Se evaluaron los datos poblacionales, presencia de comorbilidades, y resultados de los cultivos. En ese período, se internaron 140 pacientes con diagnóstico de celulitis y a todos ellos se les realizó hemocultivo y cultivos de PPB. Setenta y cuatro eran varones (52.8%. La edad promedio: 47.5 ± 19.7 años (rango 16-94. El 40% tuvo cultivos positivos de PPB, en los que el Staphylococcus aureus meticilino resistente (SAMR fue el germen más frecuentemente aislado (35.7%; la prevalencia de bacteriemia fue del 8.6%, en donde el germen más frecuente fue Streptoccocus Beta hemolítico, grupo G (33% del total de hemocultivos positivos. La bacteriemia se asoció significativamente a mayor estadía hospitalaria (10.5 ± 8.9 vs. 4.9 ± 6, p = 0.004. Se asoció con mayor riesgo de hemocultivo positivo a ser diabético, tener cultivo de PPB positivo, consumo de alcohol y/o enfermedad pulmonar obstructiva crónica.Cellulitis is an acute inflammation of dermis and subcutaneous tissue, usually complicating wounds, ulcers, or dermatosis. Even though in these cases it is recommended to perform culture from skin and soft tissue samples, the utility of blood cultures remains controversial due to the low frequency of positive results. Here we report the prevalence of bacteremia in patients with cellulitis admitted in our

  11. FLAVONOIDES AISLADOS DE LAS INFLORESCENCIAS DE Piper hispidum Kunth (PIPERACEAE Y DERIVADOS ACETILADOS

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    Luis Enrique Cuca

    2009-04-01

    Full Text Available A partir del extracto etanólico de las inflorescencias de la especie Piper hispidum Kunth (Piperaceae fueron aislados tres flavonoides: 5-hidroxi-7-metoxiflavanona, 5-hidroxi-4’,7-dimetoxiflavanona y 2’,4’,6’-trimetoxidihidrochalcona. De las flavanonas aisladas fueron obtenidos los  derivados acetilados: 5-acetoxi-7-metoxiflavanona y  5-acetoxi-4’,7-dimetoxiflavanona. Las estructuras fueron elucidadas empleando técnicas espectroscópicas y por comparación con datos de literatura. Los compuestos naturales y sus derivados fueron sometidos al bioensayo de letalidad frente a Artemia salina. El flavonoide 5-hidroxi-7-metoxiflavanona presenta la mayor actividad tóxica frente a los microcrustaceos CL50 1.8 µg/ml.

  12. Situación de Staphylococcus aureus resistente a meticilina en el Hospital de Navarra (2000-2002 State of methicillin resistant Staphylococcus aureus in the Hospital of Navarre (2000-2002

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    A. Navascués

    2004-04-01

    Full Text Available Fundamento. El objetivo del presente trabajo ha sido conocer la prevalencia y características que presentan los aislamientos de Staphylococcus aureus resistentes a meticilina aislados en nuestro Servicio de Microbiología. Material y métodos. El estudio se desarrolló de forma retrospectiva abarcando los años 2000, 2001 y 2002. Se analizó el origen de la infección (nosocomial o extrahospitalaria, servicio de origen en caso de ser nosocomial, localización anatómica de la muestra y patrón de sensibilidad antibiótica. Resultados. Los aislamientos de Staphylococcus aureus resistentes a meticilina constituyeron el 7,88% de los Staphylococcus aureus aislados en nuestro servicio. Menos de la mitad de las cepas (44,87% tuvieron un origen nosocomial y se aislaron con mayor frecuencia en los exudados de heridas. En cuanto al patrón de resistencia, hubo un 50% de resistencia a eritromicina, un 43,60% a clindamicina y un 21,79% a mupirocina. Conclusiones. La prevalencia y el patrón de resistencia in vitro de los aislamientos de Staphylococcus aureus resistentes a meticilina obtenidos en nuestro hospital es menor a la publicada en otras áreas de España.Background. The aim of the present paper was to determine the prevalence and characteristics shown by isolations of Methicillin Resistant Staphylococcus Aureus, isolated in our Microbiology Service. Methods. Retrospective study, covering the years 2000, 2001 and 2002. Analysis was made of the origin of the infection (nosocomial or non-nosocomial, the unit of origin in the event of nosocomial origin, anatomical localisation of the sample, and pattern of antibiotic sensitivity. Results. The isolations of Methicillin Resistant Staphylococcus aureus accounted for 7.88% of the Staphylococcus aureus isolated. Less than half of the strains (44.87% had a nosocomial origin and were most often isolated in the exudates of wounds. With respect to the pattern of resistance, there was some 50% of resistance to

  13. Mundos aislados: segregación urbana y desigualdad en la ciudad de México

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    GONZALO A SARAVÍ

    2008-12-01

    Full Text Available De qué nos habla la segregación urbana en México y cuáles son sus implicaciones en este contexto en particular, son las dos preguntas centrales que guían el análisis desarrollado en este artículo. El argumento que responde a estas dos preguntas se estructura en torno a la hipótesis de una "coexistencia de mundos aislados". Para sustentar dicha hipótesis, el autor analiza teórica y empíricamente la relación entre las dimensiones objetiva y simbólica de la segregación urbana. El análisis se basa en datos secundarios y en información obtenida a partir de entrevistas semi-estructuradas con jóvenes residentes en colonias populares y estigmatizadas de la Ciudad de México.What does urban segregation mean in México and what are its implications for this particular context? This article poses these two questions. Our response is based on the hypothesis of the "co-existence of isolated worlds." In order to support and develop this hypothesis, the author analyses the relationship between the objective and symbolic dimensions of urban segregation. The analysis is based on secondary data and semi-structured interviews with young people from poor and stigmatized neighborhoods in México City.

  14. Colonization of nursing professionals by Staphylococcus aureus La colonización de los profesionales de enfermería por Staphylococcus aureus A colonização dos profissionais de enfermagem por Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Josely Pinto de Moura

    2011-04-01

    Full Text Available This cross-sectional study aimed to investigate the presence of Staphylococcus aureus in the saliva of the nursing team of a teaching hospital in the interior of São Paulo State. Three saliva samples were collected from 351 individuals with an interval of two months between each collection. All ethical aspects were considered. In 867 (82.3% cultures there was no identification of Staphylococcus aureus in the saliva, in 88 (17.7% cultures Staphylococcus aureus was isolated, 26 (2.5% of which were resistant to methicillin. The prevalence of professionals colonized by Staphylococcus aureus was 41.0% (144/351, of which 7.1% (25/351 were characterized as methicillin-resistant Staphylococcus aureus. Transient carriers represented 81.2% and persistent carriers 18.8%. Resistance to mupirocin was 73.1% of MRSA and 9.3% of MSSA. The results demonstrate that it is the nurse and nursing technician that are the professional categories most susceptible to MRSA. Broader discussion on the thematic and interventions are needed.Se trata de un estudio transversal que tuvo como objetivo investigar la presencia de Staphylococcus aureus en la saliva del equipo de enfermería de un hospital escuela del interior del estado de Sao Paulo. Fueron recolectadas tres muestras de saliva de 351 individuos con intervalo de dos meses. Todos los aspectos éticos fueron contemplados. En 867 (82,3% culturas no hubo identificación de Staphylococcus aureus en la saliva, en 88 (17,7% culturas fue aislado Staphylococcus aureus, siendo 26 (2,5% resistentes a la meticilina. La prevalencia de profesionales colonizados por Staphylococcus aureus fue de 41,0% (144/351, de los cuales 7,1% (25/351 fueron caracterizados como Staphylococcus aureus resistentes a la meticilina. Los portadores transitorios representaron 81,2% y los persistentes 18,8%. La resistencia a la mupirocina fue de 73,1% entre los resistentes a la meticilina y 9,3% en los sensibles a la meticilina. Los resultados

  15. NUEVOS AISLADOS DE Gluconacetobacter diazotrophicus EN CULTIVOS DE IMPORTANCIA ECONÓMICA PARA CUBA

    Directory of Open Access Journals (Sweden)

    B. Dibut

    2005-01-01

    Full Text Available En los últimos años, un llamado importante para los microbiólogos del suelo ha sido el estudio de microorganismos endófitos que se asocian con plantas superiores, con el consiguiente beneficio sobre los cultivos. En este trabajo, se ofrecen los resultados sobre el aislamiento y la distribución de Gluconacetobacter diazotrophicus en cultivos de importancia económica para Cuba. La bacteria se aisló a partir de filtrados y secciones de diferentes órganos del vegetal dispuestos sobre medios de cultivo LGI-P, donde se comprobó el crecimiento característico a las 96 h de incubación a 320C de temperatura, obteniéndose finalmente 22 aislados a partir de diez especies cultivables. Experimentos de dinámica poblacional desarrollados en condiciones de invernadero mediante diseño completamente aleatorizado permitieron cuantificar el microorganismo en hojas, tallos y raíces de maíz, boniato, yuca, malanga y caña de azúcar, con poblaciones que oscilan entre 1.8 x 102-2.3 x 107 células por gramo de tejido fresco. Las poblaciones celulares más altas se detectaron en las hojas, seguido de los tallos y por último las raíces o tubérculos. La respuesta favorable de ocho cultivos a la inoculación de la bacteria, esta vez crecida en medio de cultivo SG e incubada a 320C durante 72 h, permite plantear la potencialidad que este microorganismo presenta como biofertilizante. Se informa por primera vez la presencia de la Gluconacetobacter diazotrophicus en cinco especies de plantas pertenecientes cada una a diferentes familias botánicas.

  16. Evaluación in vitro de la actividad inhibitoria de extractos vegetales sobre aislados de Colletotrichum spp

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    Rojas Sierra2 Johanna

    2011-06-01

    Full Text Available Se evaluó la actividad inhibitoria in vitro de extractos de hojas de Melissa officinalis, Origanum vulgare,Jatropha gossypilia, Eucalyptus sp., Melia azederach y Mascagnia concinna sobre aislados de hongo delgénero Colletotrichum, causante de la enfermedad antracnosis en el cultivo del ñame (Dioscorea alata, D.rotundata en el departamento de Sucre, Colombia. Para la obtención de extractos etanólicos de hojasde M. officinalis y O. vulgare, se utilizó el método de percolación y para las otras especies vegetales, elmétodo de Soxhlet. Una vez preparados los extractos de hojas, se evaluó su actividad inhibitoria sobreseis aislados de hongo del género Colletotrichum (BVC 279a, BVC 279b, BVC 853, BVC 040, BVC 342 yBVC 507. Para la prueba inhibitoria se utilizó el método de siembra directa sobre la superficie del mediopapa-dextrosa-agar. Sobre las diferentes cepas se adicionaron 250 μl de cada extracto por separado. Seutilizó un control positivo con nistatina (4 mg/ml y un testigo absoluto sin ningún tipo de tratamiento.La prueba se evaluó midiendo el crecimiento radial de cada cepa con los diferentes tratamientos a 96y 168 h. Se utilizó un diseño de bloques completamente al azar con tres repeticiones, para probardiferencias significativas entre tratamientos, cepas (aislados y tiempo de inhibición. Los resultadosexpresados en porcentaje de inhibición, mostraron una alta actividad de los extractos obtenidos de lashojas de las plantas de M. azederach y M. concinna, sobre los hongos evaluados y su acción fue similaral control positivo

  17. Evaluación in vitro de la actividad inhibitoria de extractos vegetales sobre aislados de Colletotrichum spp

    Directory of Open Access Journals (Sweden)

    Alexander Pérez Cordero

    2011-04-01

    Full Text Available Se evaluó la actividad inhibitoria in vitro de extractos de hojas de Melissa officinalis, Origanum vulgare, Jatropha gossypilia, Eucalyptus sp., Melia azederach y Mascagnia concinna sobre aislados de hongo del género Colletotrichum, causante de la enfermedad antracnosis en el cultivo del ñame (Dioscorea alata, D. rotundata en el departamento de Sucre, Colombia. Para la obtención de extractos etanólicos de hojas de M. officinalis y O. vulgare, se utilizó el método de percolación y para las otras especies vegetales, el método de Soxhlet. Una vez preparados los extractos de hojas, se evaluó su actividad inhibitoria sobre seis aislados de hongo del género Colletotrichum (BVC 279a, BVC 279b, BVC 853, BVC 040, BVC 342 y BVC 507. Para la prueba inhibitoria se utilizó el método de siembra directa sobre la superficie del medio papa-dextrosa-agar. Sobre las diferentes cepas se adicionaron 250 µl de cada extracto por separado. Se utilizó un control positivo con nistatina (4 mg/ml y un testigo absoluto sin ningún tipo de tratamiento. La prueba se evaluó midiendo el crecimiento radial de cada cepa con los diferentes tratamientos a 96 y 168 h. Se utilizó un diseño de bloques completamente al azar con tres repeticiones, para probar diferencias significativas entre tratamientos, cepas (aislados y tiempo de inhibición. Los resultados expresados en porcentaje de inhibición, mostraron una alta actividad de los extractos obtenidos de las hojas de las plantas de M. azederach y M. concinna, sobre los hongos evaluados y su acción fue similar al control positivo.

  18. Estudio anatomopatológico de aislados de Leptospira spp., provenientes de Nicaragua en Mesocricetus auratus como biomodelo

    OpenAIRE

    Willian Jirón T.; Niurka Batista S.; Daniel Arencibia A.; Luis Rosario F.; Juan Infante B.

    2015-01-01

    RESUMENObjetivo. El objetivo de este trabajo fue caracterizar en el biomodelo Mesocricetus auratus la sintomatología y lesiones anatomopatológicas que provocan 5 aislados clínicos de Leptospira spp., provenientes de Nicaragua. Materiales y métodos. Con este fin se inocularon 50 hámster por vía i.p con 1mL del cultivo de cada una de las cepas en fase exponencial teniendo una concentración celular de 7.5 x 106 leptospira/mL (10 animales por cepa), evaluándose signos de la enfermedad, mortalidad...

  19. Actividad antinociceptiva, anti-inflamatoria y relajante muscular de (+)-curcufenol aislado de la esponja marina didiscus oxeata

    OpenAIRE

    Salama, Ahmed; Toscano, Mariela; Del Valle, Martha; Vargas, Erika

    2008-01-01

    Mediante el método de edema plantar inducido por carragenina en la pata de la rata, (+)-curcufenol aislado de la esponja marina Didiscus oxeata mostró una actividad antiinflamatoria moderada, en las dosis de 100, 150 y 200 mg/kg administradas por vía oral, mientras que la actividad antinociceptiva fue confirmada por el método de contorsiones inducidas por ácido acético en ratones mostrando un efecto analgésico muy alto, en las dosis de 50, 100, 150 y 200 mg/kg administradas por vía oral, en c...

  20. Neuroprotecci??n mediada por diterpenos aislados de Sideritis spp. frente al estr??s oxidativo en astrocitos

    OpenAIRE

    Gonz??lez-Burgos, E.; Palomino, O.M.; Carretero Accame, M.E.; G??mez-Serranillos, M.P.

    2010-01-01

    La presente investigaci??n aborda el estudio de las propiedades neuroprotectoras, en base a la capacidad antioxidante, de los diterpenos andalusol, conchitriol y sidol aislados de diferentes especies del g??nero Sideritis. La actividad protectora de estos compuestos fue evaluada en un modelo de estr??s oxidativo inducido por el per??xido de hidr??geno sobre la l??nea celular U373 MG de astrocitoma humano. Los resultados mostraron que un pretratamiento durante 24 horas con los dite...

  1. Variabilidad genética de Colletotrichum spp aislado de frutos tropicales mediante el uso de marcadores moleculares RAPD.

    OpenAIRE

    Cruz Hernández, Miguel Angel

    2013-01-01

    Colletotrichum gloeosporioides presenta alta variabilidad morfológica, patogénica y genética, lo cual ha sido difícil de evaluar usando los métodos tradicionales. En los últimos años, las técnicas moleculares han facilitado la separación y caracterización genética. El presente trabajo se divide en dos fases, en la primera se realizaron los aislados, la identificación morfológica y se realizaron pruebas de efectividad bilógica in vivo e in vitro de imazalil para el control de la antracnosis en...

  2. Detección y caracterización de aislados de "escherichia coli" de origen clínico y fecal en gallinas ponedoras

    OpenAIRE

    Gibert Perelló, Magdalena

    2009-01-01

    El objetivo de esta tesis ha sido realizar la caracterización de aislados de E. coli clínicos (responsables de cuadros de colibacilosis en gallinas ponedoras) y fecales. Tras llevar a cabo el aislamiento e identificación bioquímica de los aislados, se ha procedido a la determinación del serogrupo, patotipo (detección de factores de virulencia por PCR), sensibilidad a antimicrobianos y pulsotipo (mediante la técnica de Pulsed Field-Gel Electrophoresis, PFGE). Además, se ha realizado un estudio...

  3. Actividad antimicrobiana y antitumoral de la variabilina y sus enantiomeros aislados de ircinia felix

    OpenAIRE

    Salama, Ahmen; Gamboa Estrada, Marlen; Pinzón Orjuela, Mauricio

    2008-01-01

    El presente trabajo muestra un amplio espectro antimicrobiano para la variabilina y sus enantiomeros siendo activos contra los microorganismos Gram (+) Micrococcus luteus, Staphylococcus aureus y Bacillus subtilis y los microorganismos Gram (-) Pseudomonas sp, Enterobacter aerogenes y Escherichia coli. Los compuestos no mostraron actividad contra los hongos Aspergillus tamari, Aspergillus niger y Penicillium sp, en las concentraciones ensayadas. El efecto antitumoral en disco de zanahoria se ...

  4. Staphylococcus aureus Transcriptome Architecture

    DEFF Research Database (Denmark)

    Mäder, Ulrike; Nicolas, Pierre; Depke, Maren;

    2016-01-01

    Staphylococcus aureus is a major pathogen that colonizes about 20% of the human population. Intriguingly, this Gram-positive bacterium can survive and thrive under a wide range of different conditions, both inside and outside the human body. Here, we investigated the transcriptional adaptation of S...... to their dependence on the RNA polymerase sigma factors SigA or SigB, and allow identification of new potential targets for several known transcription factors. In particular, this study revealed a relatively low abundance of antisense RNAs in S. aureus, where they overlap only 6% of the coding genes, and only 19...... antisense RNAs not co-transcribed with other genes were found. Promoter analysis and comparison with Bacillus subtilis links the small number of antisense RNAs to a less profound impact of alternative sigma factors in S. aureus. Furthermore, we revealed that Rho-dependent transcription termination...

  5. Staphylococcus aureus CC398

    DEFF Research Database (Denmark)

    Price, Lance B.; Stegger, Marc; Hasman, Henrik;

    2012-01-01

    Since its discovery in the early 2000s, methicillin-resistant Staphylococcus aureus (MRSA) clonal complex 398 (CC398) has become a rapidly emerging cause of human infections, most often associated with livestock exposure. We applied whole-genome sequence typing to characterize a diverse collection...... of CC398 isolates (n = 89), including MRSA and methicillin-susceptible S. aureus (MSSA) from animals and humans spanning 19 countries and four continents. We identified 4,238 single nucleotide polymorphisms (SNPs) among the 89 core genomes. Minimal homoplasy (consistency index = 0.9591) was detected...

  6. Nuevo alcaloide oxoaporfínico y otros constituyentes químicos aislados de Pleurothyrium cinereum (Lauraceae.

    Directory of Open Access Journals (Sweden)

    Ericsson Coy

    2009-04-01

    Full Text Available Del extracto etanólico de las hojas de Pleurothyrium cinereum (Lauraceae fue aislado el nuevo alcaloide oxoaporfínico oxiprenilado 1,2-metilendioxi-9,10-dimetoxi-3-isopreniloxi-7H-dibenzo[de,g]quinolin-7-ona (Pleurotirina 1, el cual fue purificado por  métodos cromatográficos y cuya elucidación estructural se realizó mediante técnicas espectroscópicas (RMN-1H, RMN-13C, RMN-2D y EM. Junto al alcaloide 1 fueron aislados los compuestos thalicminina 2, ácido ent-kaurenóico 3, alloxantoxiletina 4, xantiletina 5, dihydroflavokawina B 6, 3’-metoxi-3,4-metilendioxi-4’,7-epoxi-nor-8.5’-neolignan-7.8’-dieno 7 y friedelina 8, los cuales se reportan por primera vez para la especie y para el género.

  7. Caracterización bioquímica y molecular de aislados de Klebsiella pneumoniae resistente a antimicrobianos

    Directory of Open Access Journals (Sweden)

    Laura Margarita Castañeda

    2000-02-01

    diferentes aislados bacterianos resistentes a antibióticos, son insuficientes para discriminar un posible brote de infección nosocomial, siendo necesaria la utilización de técnicas basadas en el estudio genotípico, que logren establecer diferencias entre los aislados.

    El análisis del perfil de plásmidos es de mucha aplicabilidad, ya que permite una evaluación epidemiológica útil para determinar la diferencia o la semejanza entre los aislados sometidos a estudio. Sin embargo, no es suficiente para determinar el origen clonal de un brote y se requiere un método que permita una caracterización mas precisa de las cepas. Para este fin, se utiliza el análisis del DNA genómico, cortado con endonucleasas de restricción con baja frecuencia de corte, por medio de la electroforesis de campo pulsado (PFGE, que ha mostrado ser una buena herramienta epidemiológica, debido a su alta reproducibilidad y a su poder discriminatorio para determinar el origen clonal en varias especies bacterianas incluyendo Klebsiella pneunoniae, Este proyecto pretende determinar y caracterizar el comportamiento genético de esta resistencia en las cepas de Klebsiella pneumoniae circulantes en nuestro medio, lo que permitirá plantear estrategias epidemiológicas en el manejo y prevención de las diferentes infecciones debidas a este microorganismo.

    Objetivo general: Caracterizar bioquímica y molecularmente aislados de Klebsiella pneumoniae resistentes a antimicrobianos.

    Objetivos específicos: 1. Biotipificar los aislados de Klebsiella pneumoniae. 2. Determinar la susceptibilidad de los aislados, incluyendo la detección de la producci

  8. Efecto de aislados bacterianos de la familia de las rhizobacterias provenientes de alfalfa (Medicago sativa) en la mejora del crecimiento de plantas de frijol (Phaseolus vulgaris) y nodulación en jitomate (Solanum lycopersicon)

    OpenAIRE

    Alma Lilián Guerrero Barrera; Cristina Garcidueñas Piña; Ilse Patricia Rivas Valdéz; Ezequiel Alejandro Madrigal Carrillo; José Francisco Morales Domínguez

    2009-01-01

    Se evaluó el efecto de aislados de rhizobacterias provenientes de alfalfa (Medicago sativa L.), en el crecimiento y expresión de proteínas en plantas de frijol (Phaseolus vulgaris) y jitomate (Solanum lycopersicon). Se obtuvieron dos diferentes aislados; A y Ab, los cuales se inocularon en semillas de frijol Bayo, Pinto y Negro y de jitomate Bola y Río Grande. Los mejores resultados en crecimiento se observaron en el frijol Pinto y el Bayo con los aislados A y Ab, respectivamente. En el jito...

  9. Resistencia antibiótica asociada a integrones de clase 1 en aislados humanos de enterobacterias de dos contextos epidemiológicos: zoonosis por "Salmonella enterica" e infección por "Klebsiella pneumoniae" adquirida en un centro sociosanitario

    OpenAIRE

    Pérez Moreno, Mª del Mar

    2011-01-01

    [spa] OBJETIVO: Establecer la contribución de los integrones de clase 1 a la resistencia antibiótica en aislados clínicos de enterobacterias de dos contextos epidemiológicos: zoonosis por Salmonella enterica e infección por Klebsiella pneumoniae resistente a amoxicilina/clavulánico (ACL) adquirida en un centro sociosanitario. AISLADOS: Se estudiaron (a) 92 aislados humanos de Salmonella enterica serotipo Typhimurium (ST) recuperados entre 2004 y 2006 en el laboratorio de microbiología del ...

  10. Digestibilidad de nutrimentos en lechones alimentados con dietas con aislado o concentrado de proteína de soya

    OpenAIRE

    Maria de los Angeles Aguilera Barreiro; Tércia Cesária Reis de Souza; Gerardo Mariscal Landín; Arturo Germán Borbolla Sosa; Araceli Aguilera Barreyro

    2006-01-01

    Se utilizaron 15 lechones destetados a los 17 días con 6.1 ± 1.8 kg para medir el efecto de la fuente de proteína sobre la digestibilidad de tres dietas, una con concentrado de proteína de soya (CPS) y las otras dos con aislado de proteína de soya solo (APS) o con suero de leche (APSSL). Se determinó la digestibilidad ileal y total aparente (DIA y DTA) de materia seca (MS), proteína cruda (PC) y energía (En) en tres periodos (P): P1= 26-29; P2= 33-36 y P3= 40-43 días. La DIA-MS fue mayor (P0....

  11. Embolia pulmonar séptica de origen cutáneo

    Directory of Open Access Journals (Sweden)

    Agustina Sosa Beláustegui

    2012-08-01

    Full Text Available La embolia pulmonar séptica es una enfermedad grave y poco frecuente que se caracteriza por presentar infiltrados pulmonares bilaterales asociados a un foco infeccioso extrapulmonar. Se relaciona principalmente a endocarditis derecha, tromboflebitis pelviana, accesos vasculares y menos frecuentemente a infecciones profundas como osteomielitis, artritis séptica o piomiositis. El Staphylococcus aureus meticilino-resistente adquirido en la comunidad (SAMR-AC es un patógeno emergente, con alta virulencia y de rápida propagación, que afecta a sujetos sin enfermedades previas relacionadas o factores de riesgo conocidos. Causa infecciones de piel y partes blandas y con menor frecuencia infecciones graves como fascitis necrotizante, artritis séptica, osteomielitis, piomiositis y neumonía necrotizante. Su epidemiología, patogenia y manifestaciones clínicas difieren de las causadas por el SAMR adquirido en el hospital. Presentamos el caso de un varón de 67 años con embolias pulmonares sépticas causadas por SAMR-AC con origen en una infección cutánea.

  12. Triterpenos aislados de corteza de Bursera graveolens (Burseraceae y su actividad biologica

    Directory of Open Access Journals (Sweden)

    Jorge Robles

    2005-12-01

    Full Text Available Bursera graveolens (Burseraceae, known in Colombia as "sasafrás", is useful for its medicinal properties and is rich in secondary metabolites. In our research, we carried out antimicrobial tests of several fractions and ethanolic extracts from aerial parts against Bacillus subtilis and Staphylococcus aureus, that showed growth inhibitory activity when applied at 250 mg/mL for extracts and 150 mg/mL for fractions. We carried out an antiinflamatory assay also, that showed 71% of inhibition by extracts (81% of Indomethacin and 70% of inhibition by fractions (78% of Indomethacin. Phytochemical investigation of the bark of Bursera graveolens (Burseraceae yielded three tetracyclic triterpene acids that have oxygenation in C-3, carboxylic acid in C-21 and unsaturation in C-24 and have been identified as 3-oxotirucalla-8,24-dien-21-oic acid (b-elemonic acid, 3a-hydroxytirucalla-8,24-dien-21-oic acid (a-elemolic acid and 3a-hydroxytirucalla-7,24-dien-21-oic acid. The isolated compounds were identified using spectroscopic methods including one and two-dimensional Nuclear Magnetic Resonance (COSY, HMQC, HMBC, NOESY experiments and comparison with published data. This is the first report of the isolated compounds in Bursera graveolens and they have a very important chemotaxonomic significance within the Burseraceae family and related families from the order Rutales.

  13. Estudio de aislados no patogénicos de Fusarium oxysporum para el control biológico de patógenos fúngicos oportunistas

    OpenAIRE

    Arroyo Gallardo, Víctor

    2015-01-01

    Los hongos oportunistas afectan numerosas especies vegetales tanto en los cultivos como en productos almacenados. Este tipo de enfermedades son muy difíciles de combatir mediante el empleo de fitosanitarios. La aplicación de los mismos se encuentra muy limitada y es especialmente importante en productos destinados a consumo. Por ello, en el presente estudio planteamos el control biológico como alternativa. Para conseguir este objetivo, trabajamos con siete aislados no patogénicos de Fus...

  14. Linezolid resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Pavani Gandham

    2014-08-01

    Full Text Available Linezolid is the only antibiotic available as an oral formulation for resistant staphylococcal infections. It is effective in skin and soft tissue infections, nosocomial pneumonias including VAP, infective endocarditis and MRSA meningitis. It is also effective in the eradication of both nasal and throat colonization of MRSA. Its high bioavailability and post antibiotic effect, ease of switching to oral therapy during its use and the fact that it can be used in patients of all ages, also in patients with liver disease and poor kidney function and its increased effectiveness over glycopeptides makes this drug a precious drug in the treatment of resistant staphylococcal infections. Linezolid resistance in staphylococcus is defined as a linezolid MIC of and #8805;8 mg/L. Reported Linezolid resistance in India and elsewhere is 2-20%. There is clonal dissemination of Linezolid Resistant Staphylococcus aureus (LRSA within or across health care settings which demands continuous surveillance to determine the emergent risk of resistance strains and to establish guidelines for appropriate use. Clinical laboratories should confirm any LRSA preferably by a second method, prior to using linezolid for serious infections. Effective surveillance, more judicious use of this antibiotic, avoiding linezolid usage for empiric therapy in hospital acquired staphylococcus infections, optimization of the pharmacological parameters of the antibiotics in specific clinical situation, decreasing bacterial load by timely surgical debridement or drainage of collections, use of combination therapies would prevent the emergence of resistance to linezolid in staphylococcus aureus. [Int J Res Med Sci 2014; 2(4.000: 1253-1256

  15. Staphylococcus aureus triggered reactive arthritis.

    OpenAIRE

    Siam, A R; M. Hammoudeh

    1995-01-01

    OBJECTIVES--To report two patients who developed reactive arthritis in association with Staphylococcus aureus infection. METHODS--A review of the case notes of two patients. RESULTS--Two adult female patients have developed sterile arthritis in association with Staph aureus infection. The first patient has had two episodes of arthritis; the first followed olecranon bursitis, the second followed infection of a central venous catheter used for dialysis. The second patient developed sterile arth...

  16. Staphylococcus aureus and sore nipples.

    OpenAIRE

    Livingstone, V. H.; Willis, C. E.; Berkowitz, J

    1996-01-01

    OBJECTIVE: To correlate clinical symptoms and signs of sore nipples with the presence of Staphylococcus aureus and to determine the probability of mothers having S aureus-infected nipples when these local symptoms and signs are found. DESIGN: Two cohorts of consecutive patients were enrolled regardless of presenting complaint. A questionnaire was administered to determine the presence and severity of sore nipples. Objective findings on breast examination were documented. A nipple swab was tak...

  17. Virus de la Enfermedad Infecciosa de la Bolsa de Fabricio: Relaciones antigénicas de aislados cubanos y chilenos Infectious Bursal Disease Virus: antigenic interrelationships between

    Directory of Open Access Journals (Sweden)

    J Noda

    2005-01-01

    Full Text Available La Enfermedad Infecciosa de la Bolsa (EIB sigue afectando la industria avícola por la aparición de variantes patogénicas y antigénicas del virus, originadas en la permanente evolución del virus producto de la presión inmunológica por el uso intensivo de vacunas. La caracterización antigénica de los virus de campo resulta esencial para la aplicación de vacunas más adecuadas en el control de la enfermedad. En este trabajo se determinaron las relaciones antigénicas de aislados cubanos y chilenos, obtenidos de poblaciones de pollos vacunados con el virus de la EIB. Los aislados virales se adaptaron a cultivos celulares y se obtuvieron antisueros monoespecíficos de cada uno de ellos y de una cepa de referencia. Las relaciones se establecieron por virusneu-tralización cruzada utilizando nueve aislados cubanos (BD, BL, 35/95, 29/96, 118/96, BF2, BF8, BF9 y 70/98, tres chilenos (G1, G2 y G4 y una cepa de referencia del serotipo 1 (Lukert. Los aislados cubanos y chilenos se adaptaron eficientemente a cultivos de fibroblastos de embrión de pollo (con excepción de BF3 y G3. Además, los aislados cubanos se adaptaron a células VERO, presentando mayores títulos infectivos en fibroblastos de embrión de pollo que en esta línea celular. Los resultados de la seroneutralización cruzada mostraron entre los aislados cubanos una relación mayor a un 80% y entre éstos y la cepa de referencia mayor de un 70%, de igual modo con los aislados chilenos G1 y G4 (mayor de 77%. El aislado G2 presentó diferencias antigénicas consideradas menores con los aislados cubanos BL, 35/95 y 29/96 (­ 69%. Ninguno de los aislados mostró relaciones antigénicas inferiores al 30% con la cepa de referencia del serotipo 1, por lo tanto no corresponden a cepas variantesInfectious Bursal Disease (IBD is still affecting the poultry industry through the appearance of pathogenic and antigenic variations of the virus. This is due to its permanent evolution as a

  18. Estudio anatomopatológico de aislados de Leptospira spp., provenientes de Nicaragua en Mesocricetus auratus como biomodelo

    Directory of Open Access Journals (Sweden)

    Willian Jirón T.

    2013-08-01

    Full Text Available Objetivo. El objetivo de este trabajo fue caracterizar en el biomodelo Mesocricetus auratus la sintomatología y lesiones anatomopatológicas que provocan 5 aislados clínicos de Leptospira spp., provenientes de Nicaragua. Materiales y métodos. Con este fin se inocularon 50 hámster por vía i.p con 1mL del cultivo de cada una de las cepas en fase exponencial teniendo una concentración celular de 7.5 x 106 leptospira/mL (10 animales por cepa, evaluándose signos de la enfermedad, mortalidad durante 14 días, lesiones anatomopatológicas macroscópicas y microscópicas mediante tinción con hematoxilina-eosina y tinción de Warthyn Starryn. Resultados. Todas las cepas presentaron alta mortalidad, mostrando un cuadro tanto clínico, como lesional característico de la infección experimental. Además, causaron la muerte al 100% de los animales entre el tercer y décimo día postinfección. En el estudio anatomopatológico la cepa del serogrupo Ballum y la del serogrupo Pomona produjeron focos de hemorragias específicamente en el riñón y pulmones. De forma similar ocurrió una congestión hepática y renal, mientras que la hemorragia renal fue observada con mayor frecuencia en la cepa del serogrupo Pomona, diferenciándose del resto de las cepas que mostraron esta lesión con menos frecuencia. Conclusiones. Este trabajo permitió una mayor caracterización de estas cepas siendo utilizadas como futuras candidatas vacunales frente a una nueva epidemia de Leptospirosis en Nicaragua.

  19. Gérmenes patógenos aislados en niños con infecciones respiratorias a repetición

    Directory of Open Access Journals (Sweden)

    Yoenny Peña García

    2015-01-01

    Full Text Available Las infecciones respiratorias agudas son la causa más frecuente de morbilidad y de elevada mortalidad en el mundo, particularmente en los países en desarrollo. Se realizó un estudio descriptivo de corte transversal, para caracterizar a los niños con infecciones respiratorias a repetición, según los gérmenes patógenos aislados, en el círculo infantil “Flores de la Vida” del municipio de Puerto Padre, en el período de abril a mayo de 2014. Se trabajó con los niños de los salones de segundo, tercero y cuarto año de vida, distribuidos según edad y sexo, a los que se les identificaron los gérmenes patógenos aislados en exudados nasofaríngeos. La información se obtuvo del departamento de microbiología del Centro Municipal de Higiene y Epidemiología. Se obtuvieron los siguientes resultados: el grupo de edad más frecuente fue el de dos años, que representó el 45 % de la muestra y se correspondió con la media de la edad. El 62,5 % de la muestra de estudio correspondió al sexo masculino. Los gérmenes patógenos aislados con mayor frecuencia fueron: el Streptococcus pneumoneae, para un 83,9 %, el Streptococcus B hemolítico, para un 7,1 % y el Haemophillus inflienzae para un 5,4 %

  20. Virus de la Enfermedad Infecciosa de la Bolsa de Fabricio: Relaciones antigénicas de aislados cubanos y chilenos Infectious Bursal Disease Virus: antigenic interrelationships between

    OpenAIRE

    J Noda; J ULLOA; C L Perera; G Jara; Cuello, S.; E. Rodríguez

    2005-01-01

    La Enfermedad Infecciosa de la Bolsa (EIB) sigue afectando la industria avícola por la aparición de variantes patogénicas y antigénicas del virus, originadas en la permanente evolución del virus producto de la presión inmunológica por el uso intensivo de vacunas. La caracterización antigénica de los virus de campo resulta esencial para la aplicación de vacunas más adecuadas en el control de la enfermedad. En este trabajo se determinaron las relaciones antigénicas de aislados cubanos y chileno...

  1. Selección de hongos aislados de bagazo de caña con actividad celulasa sobre celulosa cristalina para posibles aplicaciones industriales

    OpenAIRE

    Yoandy Ferrer-Marcelo; Marta León-Rodríguez; Georgina Michelena-Álvarez; Julio César Dustet-Mendoza; Arianna Duque-Ortiz; My-Lai Ibañez-Fuentes; Keyla Tortoló-Cabañas

    2011-01-01

    Las enzimas comerciales necesarias en procesos de producción de bioetanol celulósico y enriquecimiento de forrajes, son excesivamente caras. La mayoría provienen de mutantes B-glucosidasa, con la velocidad y extensión de la hidrólisis reducida, y débil acción sobre la celulosa cristalina. A partir de bagazo, se aislaron varios hongos filamentosos con capacidad de degradación de la celulosa cristalina, para ello se diseñó un medio selectivo de celulosa agar. Del total de aislados, solo 9 micro...

  2. Variabilidad morfológica, patogénica y susceptibilidad a fungicidas de Rhizoctonia solani aislado de rizósfera de Vitis vinifera var. perlette seedless

    OpenAIRE

    Amparo Meza-Moller; Martín Esqueda; Alfonso Gardea; Martín Tiznado; Gil Virgen-Calleros

    2007-01-01

    Se estudió la variabilidad morfológica, reacción de anastomosis, patogenicidad y susceptibilidad a fungicidas de Rhizoctonia solani aislado de la rizósfera de Vitis vinifera var. perlette seedless plantada a pie franco en Sonora, México. El hongo se aisló mediante el método de tamizado en húmedo y la siembra en agar-agua 2 %. Se obtuvieron 122 cepas, las cuales presentaron hifas con 3 a 9 núcleos por célula, de 3 a 8 µm de diámetro y de color blanco sucio a moreno oscuro. Los aislamientos cor...

  3. Actividad antifúngica del aceite esencial de Eugenia caryophyllata sobre cepas de Candida tropicalis de aislados clínicos

    OpenAIRE

    Juliana MOURA MENDES; Felipe Queiroga SARMENTO GUERRA; de Oliveira Pereira, Fillipe; Janiere PEREIRA de SOUSA; Vinicius NOGUEIRA TRAJANO; de Oliveira Lima, Edeltrudes

    2012-01-01

    La candidiasis es una infección fúngica oportunista causada por levaduras del género Candida. En Brasil, la especie C. tropicalis esta siendo aislada frecuentemente, es el segundo microorganismo más aislado después de C. albicans. La aparición de cepas resistentes a los antifúngicos convencionales ha aumentado la búsqueda de nuevas alternativas provenientes de productos naturales, especialmente los aceites esenciales. En este estudio se investigó la actividad de los aceites esenciales contra ...

  4. Detección de aislados clínicos de Escherichia coli y Klebsiella spp. productoras de B-lactamasas de espectro extendido mediante el sistema DIRAMIC

    Directory of Open Access Journals (Sweden)

    Estrella Álvarez-Varela

    2010-01-01

    Full Text Available En los últimos años, se ha incrementado el interés por las enterobacterias productoras de B-lactamasas de espectro extendido (BLEE. Las cepas que expresan este fenotipo son capaces de hidrolizar un amplio grupo de antibióticos, incluidas las cefalosporinas de tercera generación y aztreonam, por lo que constituyen un reto terapéutico de difícil abordaje. Este mecanismo les confiere a las bacterias un grado de resistencia variable a los oximino-betalactámicos, se manifiesta en un aumento de la concentración mínima inhibitoria, que permanece en el intervalo de sensibilidad. Puede pasar inadvertido en el laboratorio, pero se manifiesta en el paciente, en el que no hay actividad de la droga y por lo tanto, se presenta una falla terapéutica. De ahí, la gran importancia de perfeccionar su detección a nivel del laboratorio de microbiología. En este trabajo, se comparó el sistema DIRAMIC con el método de sinergia de doble disco modificado (DDD para la detección fenotípica de BLEE. Se estudiaron 175 aislados clínicos, 132 Escherichia coli y 43 Klebsiella spp., provenientes de tres hospitales de Ciudad de La Habana, recolectados de junio de 2008 a junio de 2009. De un total de 42 (24 % aislados que presentaron fenotipo de BLEE por el método de DDD, el sistema DIRAMIC fue capaz de detectar 39 (22,3 %. En tres aislados, el fenotipo de BLEE solo fue detectado por DDD, los cuales resultaron falsos negativos por DIRAMIC. El 72,6 % de los aislados (127 fueron negativos por ambos métodos. Los métodos empleados tuvieron un desempeño similar, para un 92,85 % de correspondencia. El DIRAMIC mostró una sensibilidad del 92,85 % y una especificidad del 95,48 % con respecto al método de DDD.

  5. Staphylococcus aureus en quemaduras: estudio de incidencia, tendencia y pronóstico

    Directory of Open Access Journals (Sweden)

    A. García-Urquijo

    2015-06-01

    Full Text Available Realizamos un estudio descriptivo, longitudinal, retrospectivo de los últimos 10 años, en la Unidad de quemados del Hospital Universitario "Arnaldo Milián Castro" de Santa Clara, en Villa Clara, Cuba, con el objetivo de caracterizar el comportamiento del aislamiento de Staphylococcus aureus en heridas por quemaduras de pacientes ingresados. Se realizó con 1065 muestras tomadas por método cualitativo de hisopado, entre enero del 2002 y diciembre del 2011. Las variables utilizadas fueron: mes y año de realización, resultado del aislamiento, grupo de microorganismos y especies aisladas, series temporales y tasa pronóstico. Staphylococcus aureus resultó ser el microorganismos Gram positivo mas frecuentemente aislado (68,3%, representando entre el 7 y el 31,8% de las muestras realizadas cada año, con tasas de incidencias oscilando entre el 6,3 y 37,2 por cada 100 pacientes ingresados. Las tasas de incidencia mensuales se mantuvieron predominantemente en zonas de alerta y de seguridad durante los años 2011 y también en el seguimiento en 2012, sin que se produjeran picos epidémicos, mostrando una ligera tendencia al decremento con respecto al comportamiento de los 3 últimos años. Comprobamos después que la tasa de aislamiento para el siguiente año, 2012 fue de 9,5 por cada 100 ingresos, dentro de los límites del intervalo pronosticado según los estudios recogidos hasta 2011 (0 y 46,7 por cada 100 ingresos.

  6. AISLAMIENTO Y CARACTERIZACIÓN DE CEPAS DE Staphylococcus ENTEROTOXIGÉNICOS AISLADOS DE QUESOS EN BOGOTA

    OpenAIRE

    María Vanegas L; Lina González G; Aida Martínez L; Francisco Buitrago

    2008-01-01

    Objetivo. Caracterizar cepas de Staphylococcus aureus enterotoxigénicos provenientes de quesos distribuidos en supermercados, tiendas y en ventas callejeras en la ciudad de Bogota, Colombia. Materiales y métodos. Se ecolectaron muestras de quesos provenientes de tiendas, supermercados y ventas callejeras. Se detectó la presencia del gen para enterotoxina A usando un set de primers reportado en estudios previos. Un total de 50 quesos fueron analizados, 13 comercializados en tien...

  7. Collagen binding to Staphylococcus aureus

    International Nuclear Information System (INIS)

    Staphylococcus aureus can bind soluble collagen in a specific, saturable manner. We have previously shown that some variability exists in the degree of collagen binding between different strains of heat-killed, formaldehyde-fixed S. aureus which are commercially available as immunologic reagents. The present study demonstrates that live S. aureus of the Cowan 1 strain binds amounts of collagen per organism equivalent to those demonstrated previously in heat-killed, formaldehyde-fixed bacteria but has an affinity over 100 times greater, with Kd values of 9.7 X 10(-11) M and 4.3 X 10(-8) M for live and heat-killed organisms, respectively. Studies were also carried out with S. aureus killed by ionizing radiation, since this method of killing the organism seemed less likely to alter the binding moieties on the surface than did heat killing. Bacteria killed by exposure to gamma radiation bound collagen in a manner essentially indistinguishable from that of live organisms. Binding of collagen to irradiated cells of the Cowan 1 strain was rapid, with equilibrium reached by 30 min at 22 degrees C, and was fully reversible. The binding was not inhibited by fibronectin, fibrinogen, C1q, or immunoglobulin G, suggesting a binding site for collagen distinct from those for these proteins. Collagen binding was virtually eliminated in trypsin-treated organisms, indicating that the binding site has a protein component. Of four strains examined, Cowan 1 and S. aureus ATCC 25923 showed saturable, specific binding, while strains Woods and S4 showed a complete lack of binding. These results suggest that some strains of S. aureus contain high-affinity binding sites for collagen. While the number of binding sites per bacterium varied sixfold in the two collagen-binding strains, the apparent affinity was similar

  8. Host-adaptive evolution of Staphylococcus aureus

    OpenAIRE

    Lowder, Bethan Victoria

    2011-01-01

    Staphylococcus aureus is a notorious human pathogen associated with severe nosocomial and community-acquired infections. In addition, S. aureus is a major cause of animal diseases including skeletal infections of poultry and bovine and ovine mastitis, which are a large economic burden on the broiler chicken and dairy farming industries. The population structure of S. aureus associated with humans has been well studied. However, despite the prevalence of S. aureus infections in ...

  9. Genome Sequence of the Clinical Isolate Staphylococcus aureus subsp. aureus Strain UAMS-1

    OpenAIRE

    Sassi, Mohamed; Sharma, Deepak; Brinsmade, Shaun ,; Felden, Brice; Augagneur, Yoann

    2015-01-01

    We report here the draft genome sequence of Staphylococcus aureus subsp. aureus strain UAMS-1. UAMS-1 is a virulent oxacillin-susceptible clinical isolate. Its genome is composed of 2,763,963 bp and will be useful for further gene expression analysis using RNA sequencing (RNA-seq) technology. S taphylococcus aureus is an opportunistic human bacterial pathogen responsible for nosocomial and community-associated infections. S. aureus subsp. aureus strain UAMS-1 was originally isolated from the ...

  10. Staphylococcus aureus and hand eczema severity

    DEFF Research Database (Denmark)

    Haslund, P; Bangsgaard, N; Jarløv, J O;

    2009-01-01

    BACKGROUND: The role of bacterial infections in hand eczema (HE) remains to be assessed. OBJECTIVES: To determine the prevalence of Staphylococcus aureus in patients with HE compared with controls, and to relate presence of S. aureus, subtypes and toxin production to severity of HE. METHODS......: Bacterial swabs were taken at three different visits from the hand and nose in 50 patients with HE and 50 controls. Staphylococcus aureus was subtyped by spa typing and assigned to clonal complexes (CCs), and isolates were tested for exotoxin-producing S. aureus strains. The Hand Eczema Severity Index...... was used for severity assessment. RESULTS: Staphylococcus aureus was found on the hands in 24 patients with HE and four controls (P aureus was found to be related to increased severity of the eczema (P aureus types on the hands...

  11. Genome sequence of type strain of Staphylococcus aureus subsp. aureus

    OpenAIRE

    Kim, Bong-Soo; Yi, Hana; Chun, Jongsik; Cha, Chang-Jun

    2014-01-01

    Background Staphylococcus aureus is a pathogen that causes food poisoning and community-associated infection with antibiotic resistance. This species is an indigenous intestinal microbe found in infants and not found in adult intestine. The relatively small genome size and rapid evolution of antibiotic resistance genes in the species have been drawing an increasing attention in public health. To extend our understanding of the species and use the genome data for comparative genomic studies, w...

  12. Diseño de la Formulación de un Material de Empaque Flexible y Comestible a Base de Aislado Proteínico de Suero

    Directory of Open Access Journals (Sweden)

    Carlos Regalado González

    2005-01-01

    Full Text Available En la actualidad es muy común resguardar alimentos con empaques de plástico de naturaleza sintética. Actualmente alrededor de un 30% en peso de los desechos municipales corresponden a empaques sintéticos, lo que sugiere la necesidad de crear alternativas ecológicas de empaque, específicamente el diseño y elaboración de películas biodegradables. Dichas películas deben de tener características químicas y mecánicas apropiadas para que retarden la transferencia de masa en los sistemas de alimentos, prolonguen la vida del alimento empacado y mejoren la calidad del producto. Las películas elaboradas con aislado proteínico de suero representan una alternativa viable. Por ello el objetivo de este estudio es determinar la mejor formulación para dichas películas, a partir de los componentes básicos aislado de proteínico de suero (WPI, sorbitol no cristalizable, cera de abeja, cera de candelilla, extracto libre de células (ELC además de la medición de propiedades mecánicas de diferentes combinaciones y concentraciones de los ingredientes básicos. La metodología empleada fue preparar 21 tratamientos de películas biodegradables con aislado proteínico de suero. Posteriormente se realizaron pruebas mecánicas para la determinación del porcentaje de elongación (%E, resistencia a la tensión (RT y módulo de elasticidad (ME para la determinación de la mejor formulación. Se observó que los tratamientos que tienen 10% (w/v de sorbitol (tratamientos 5, 9,14 presentaron mejores propiedades mecánicas como un %E alto y ME alto además de una RT alta, ya que el sorbitol es el que le confiere mayor flexibilidad al empaque, en contraste con aquellas que fueron tratadas con 7% (w/v de sorbitol (tratamientos 2, 8, 12, 21 el cual muestra propiedades mecánicas indeseables, ya que se tornan quebradizas además de que presentan %E bajos así como ME altos

  13. Contribución al conocimiento de la biología y taxonomía de un hongo del género Phytium aislado del "aliso", Alnus acuminata HBK Contribución al conocimiento de la biología y taxonomía de un hongo del género Phytium aislado del "aliso", Alnus acuminata HBK

    OpenAIRE

    Cabrera Orlando; Rodríguez Esperanza; Correa de Restrepo Marina

    1990-01-01

    Se estudio la biología de un hongo aislado de la parte externa de nódulos de raíces de aliso (Alnus acumi"ata HB K), el cual presento un alto poder de germinación a bajas temperaturas (entre QOC y 4QC), condición que le confiere gran agresividad para colonizar el suelo, de tal forma que se constituye en un factor importante en la ecofisiología de las poblaciones de aliso que crecen en los bosques secundarios del sub-paramo. A partir de cultivos puros se hicieron estudios para su iden...

  14. Embolia pulmonar séptica de origen cutáneo Septic pulmonary embolism of cutaneous origin

    Directory of Open Access Journals (Sweden)

    Agustina Sosa Beláustegui

    2012-08-01

    Full Text Available La embolia pulmonar séptica es una enfermedad grave y poco frecuente que se caracteriza por presentar infiltrados pulmonares bilaterales asociados a un foco infeccioso extrapulmonar. Se relaciona principalmente a endocarditis derecha, tromboflebitis pelviana, accesos vasculares y menos frecuentemente a infecciones profundas como osteomielitis, artritis séptica o piomiositis. El Staphylococcus aureus meticilino-resistente adquirido en la comunidad (SAMR-AC es un patógeno emergente, con alta virulencia y de rápida propagación, que afecta a sujetos sin enfermedades previas relacionadas o factores de riesgo conocidos. Causa infecciones de piel y partes blandas y con menor frecuencia infecciones graves como fascitis necrotizante, artritis séptica, osteomielitis, piomiositis y neumonía necrotizante. Su epidemiología, patogenia y manifestaciones clínicas difieren de las causadas por el SAMR adquirido en el hospital. Presentamos el caso de un varón de 67 años con embolias pulmonares sépticas causadas por SAMR-AC con origen en una infección cutánea.Septic pulmonary embolism is a serious and rare illness characterized by pulmonary infiltrates associated with an extrapulmonary infectious focus. It is mainly related to right-sided endocarditis, pelvic thrombophlebitis, vascular access and less frequently to deep infections such as osteomyelitis, septic arthritis and pyomyositis. The community-acquired methicillin-resistant Staphylococcus aureus (MRSA is an emerging pathogen with high virulence and rapid spread involving subjects without previous related diseases or known risk factors. It causes infections of skin and soft tissue and less frequently other serious infections such as necrotizing fascitits, septic arthritis, osteomyelitis, pyomyositis and necrotizing pneumonia. Epidemiologically, pathogenesis and clinical manifestations differ from those caused by MRSA acquired in the hospital. We present the case of a 67 year-old male with septic

  15. Evasion of Neutrophil Killing by Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Will A. McGuinness

    2016-03-01

    Full Text Available Staphylococcus aureus causes many types of infections, ranging from self-resolving skin infections to severe or fatal pneumonia. Human innate immune cells, called polymorphonuclear leukocytes (PMNs or neutrophils, are essential for defense against S. aureus infections. Neutrophils are the most prominent cell type of the innate immune system and are capable of producing non-specific antimicrobial molecules that are effective at eliminating bacteria. Although significant progress has been made over the past few decades, our knowledge of S. aureus-host innate immune system interactions is incomplete. Most notably, S. aureus has the capacity to produce numerous molecules that are directed to protect the bacterium from neutrophils. Here we review in brief the role played by neutrophils in defense against S. aureus infection, and correspondingly, highlight selected S. aureus molecules that target key neutrophil functions.

  16. UTILIZACIÓN DE HAPLOTIPOS DE Pyricularia grisea Sacc. AISLADOS EN CUBA PARA LA SELECCIÓN DE CULTIVARES DE ARROZ RESISTENTES A LA PIRICULARIOSIS

    Directory of Open Access Journals (Sweden)

    Noraida de J. Pérez León

    2015-01-01

    Full Text Available El principal problema fitopatológico que provoca los bajos rendimientos del cultivo del arroz en Cuba es la Piriculariosi, por tal motivo se evaluaron, en condiciones controladas y con inoculación artificial, tres haplotipos de P. grisea aislados en Cuba de plantas de arroz en dos zonas de producción. Estos fueron posteriormente utilizados en la selección de cultivares de arroz resistentes a la enfermedad. Los resultados permitieron la selección de los haplotipos A 18 y B 6 para la evaluación de cultivares en condiciones semicontroladas y, de esta forma, quedan representados dos linajes del patógeno y, entre ellos, el más agresivo y ampliamente distribuido. Se seleccionaron siete líneas resistentes frente a los haplotipos evaluados, las que constituyen una importante base germoplásmica para la obtención de cultivares resistentes.

  17. Determinación de la sensibilidad a amoxicilina y a clindamicina de staphylococcus spp aislado de cavidad oral de pacientes con alto riesgo de endocarditis infecciosa

    Directory of Open Access Journals (Sweden)

    Silvia Barrientos

    2011-01-01

    Full Text Available En la literatura existen pocos estudios acerca de la distribución de Staphylococcus spp en boca y los que hay sobre estos microorganismos como residentes de la cavidad oral son controversiales.El género Staphylococcus spp conforma un importante grupo de patógenos en el ser humano y origina distintas enfermedades, entre ellas, la Endocarditis Infecciosa; de igual forma, la literatura reporta tasas de resistencia a amoxicilina y clindamicina antibióticos usados comúnmente para la profilaxis en odontología. Objetivo: Conocer la sensibilidad de Staphylococcus spp a amoxicilina y la clindamicina aislados de cavidad oral de pacientes con alto riesgo de Endocarditis Infecciosa.

  18. DENSIDAD POBLACIONAL Y ESTRUCTURA DE GRUPO DE Ateles hybridus brunneus (PRIMATES: ATELIDAE) EN UN FRAGMENTO DE BOSQUE AISLADO EN EL SURORIENTE DE ANTIOQUIA, COLOMBIA

    OpenAIRE

    Néstor J. Roncancio; Lina M. García; Amilvia Acosta

    2010-01-01

    Se encontró un grupo de Ateles hybridus brunneus en un fragmento de bosque aislado de 21 ha, con una densidad de 39 individuos/km2 (IC95% = 21.3-72.9). Esta área es la más pequeña donde se ha estimado alta densidad para Ateles. El grupo de A. h. brunneus estuvo compuesto por nueve individuos, grupo más pequeño que el registrado en otras investigaciones. Ateles tiene un sistema social fisión-fusión, donde los grupos se dividen en subgrupos. El tamaño promedio de subgrupo fue de cuatro individu...

  19. Liberación de endotelina-1 por angiotensina ll en miocitos cardíacos aislados Angiotensin II-induced endothelin-1 release in cardiac myocytes

    OpenAIRE

    María C. Villa-Abrille; Cingolani, Horacio E; Carolina D. Garciarena; Ennis, Irene L.; Aiello, Ernesto A.

    2006-01-01

    Muchos de los efectos de la angiotensina II (Ang II) son mediados en realidad por la acción de endotelina (ET) endógena liberada y/o producida en respuesta a la Ang II. En este trabajo evaluamos la interacción Ang II/ET-1, sus consecuencias en la contractilidad cardíaca y el papel de las especies reactivas del oxígeno (EROs). Se usaron cardiomiocitos aislados de gato. La Ang II, 1 nM, produjo un efecto inotrópico positivo (EIP) de 31.8±3.8% que fue cancelado por inhibición de los receptores A...

  20. Selección de hongos aislados de bagazo de caña con actividad celulasa sobre celulosa cristalina para posibles aplicaciones industriales

    Directory of Open Access Journals (Sweden)

    Yoandy Ferrer-Marcelo

    2011-01-01

    Full Text Available Las enzimas comerciales necesarias en procesos de producción de bioetanol celulósico y enriquecimiento de forrajes, son excesivamente caras. La mayoría provienen de mutantes B-glucosidasa, con la velocidad y extensión de la hidrólisis reducida, y débil acción sobre la celulosa cristalina. A partir de bagazo, se aislaron varios hongos filamentosos con capacidad de degradación de la celulosa cristalina, para ello se diseñó un medio selectivo de celulosa agar. Del total de aislados, solo 9 microorganismos mostraron un halo definido de degradación de celulosa. Se determinó el coeficiente de degradación de celulosa cristalina a través de la medición del halo formado por las colonias, y se pre-seleccionaron 5 aislados. Posteriormente, se eligieron los tres mejores productores del complejo celulasa (6, 13 y 21 mediante una fermentación sumergida por determinación de la actividad sobre papel de filtro. Se realizó una fermentación en estado sólido sobre bagazo pretratado para aumentar la actividad celulasa. Se estudió la estabilidad relativa de los extractos enzimáticos y se realizó una caracterización parcial de los mismos. Estos presentaron poca estabilidad relativa después de 48 horas, luego de un prensado simple. El mejor rango de pH de hidrólisis estuvo entre 5,5 y 6,2 y presentaron actividad enzimática a una temperatura de 40 ºC.

  1. Population structure of Staphylococcus aureus in China

    OpenAIRE

    Yan, Xiaomei

    2015-01-01

    The present PhD research was aimed at analysing the population structure of Staphylococcus aureus in China. Between 2000 and 2005 we found that patients from a single Chinese hospital showed increasing trends in antimicrobial resistance. Among methicillin-resistant S. aureus (MRSA), resistance against rifampicin doubled to 68%. Staphylococcal food poisoning (SFP) is frequent in China. Two predominant S. aureus lineages, ST6 and ST943, were identified causing outbreaks of SFP in Southern China...

  2. Immunomodulation and Disease Tolerance to Staphylococcus aureus

    OpenAIRE

    Zhigang Li; Peres, Adam G.; Andreea C. Damian; Joaquín Madrenas

    2015-01-01

    The Gram-positive bacterium Staphylococcus aureus is one of the most frequent pathogens that causes severe morbidity and mortality throughout the world. S. aureus can infect skin and soft tissues or become invasive leading to diseases such as pneumonia, endocarditis, sepsis or toxic shock syndrome. In contrast, S. aureus is also a common commensal microbe and is often part of the human nasal microbiome without causing any apparent disease. In this review, we explore the immunomodulation and d...

  3. Mastite com lesões sistêmicas por Staphylococus aureus subesp. aureus em coelhos Mastitis with systemic lesions due to Staphylococus aureus subesp. aureus in rabbits

    OpenAIRE

    Sandra Davi Traverso; Leonardo da Cunha; Joaquim César Teixeira Fernandes; Alexandre Paulino Loretti; Adriana Rhoden; Elsio Wunder Jr.; David Driemeier

    2003-01-01

    Em uma criação composta por 1800 coelhos, 33% das matrizes apresentaram mastite e lesões cutâneas crostosas e purulentas. Estes animais apresentavam-se entre 10 a- 12 meses de idade e em segunda parição. Quinze coelhos afetados foram sacrificados e necropsiados. Na necropsia, além das lesões cutâneas haviam microabscessos em diversos órgãos. Das amostras coletadas isolou-se Staphylococcus aureus subesp. aureus. S. aureus subesp. aureus também foi isolado de "swab" nasal coletado do tratador e...

  4. Immunomodulation and Disease Tolerance to Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Zhigang Li

    2015-11-01

    Full Text Available The Gram-positive bacterium Staphylococcus aureus is one of the most frequent pathogens that causes severe morbidity and mortality throughout the world. S. aureus can infect skin and soft tissues or become invasive leading to diseases such as pneumonia, endocarditis, sepsis or toxic shock syndrome. In contrast, S. aureus is also a common commensal microbe and is often part of the human nasal microbiome without causing any apparent disease. In this review, we explore the immunomodulation and disease tolerance mechanisms that promote commensalism to S. aureus.

  5. Methicillin-Resistant Staphylococcus aureus (MRSA) Treatment

    Science.gov (United States)

    ... Laboratory of Bacteriology Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA) Antibacterial Resistance Leadership Group (ARLG) NIAID Antimicrobial Resistance Funding Information ...

  6. Methicillin-Resistant Staphylococcus aureus (MRSA) Diagnosis

    Science.gov (United States)

    ... Laboratory of Bacteriology Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA) Antibacterial Resistance Leadership Group (ARLG) NIAID Antimicrobial Resistance Funding Information ...

  7. Staphylococcus aureus small colony variants in diabetic foot infections

    OpenAIRE

    Cervante-García, Estrella; García-Gonzalez, Rafael; Reyes-Torres, Angélica; Resendiz-Albor, Aldo Arturo; Salazar-Schettino, Paz María

    2015-01-01

    Background: Staphylococcus aureus (S. aureus) is one of the major pathogens causing chronic infections. The ability of S. aureus to acquire resistance to a diverse range of antimicrobial compounds results in limited treatment options, particularly in methicillin-resistant S. aureus (MRSA). A mechanism by which S. aureus develops reduced susceptibility to antimicrobials is through the formation of small colony variants (SCVs). Infections by SCVs of S. aureus are an upcoming problem due to diff...

  8. Evaluation of Two New Chromogenic Media, CHROMagar MRSA and S. aureus ID, for Identifying Staphylococcus aureus and Screening Methicillin-Resistant S. aureus

    OpenAIRE

    Hedin, Göran; Fang, Hong

    2005-01-01

    Thirty-nine methicillin-resistant Staphylococcus aureus (MRSA) isolates with diverse genetic backgrounds and two reference strains were correctly identified as S. aureus on CHROMagar MRSA and S. aureus ID media. Growth inhibition on CHROMagar MRSA was noted. A combination of cefoxitin disk and S. aureus ID was found suitable for rapid MRSA screening.

  9. The cell surface proteome of Staphylococcus aureus

    NARCIS (Netherlands)

    Dreisbach, Annette; van Dijl, Jan Maarten; Buist, Girbe

    2011-01-01

    The Gram-positive bacterium Staphylococcus aureus is a wide spread opportunistic pathogen that can cause a range of life-threatening diseases. To obtain a better understanding of the global mechanisms for pathogenesis and to identify novel targets for therapeutic interventions, the S. aureus proteom

  10. Population structure of Staphylococcus aureus in China

    NARCIS (Netherlands)

    Yan, Xiaomei

    2015-01-01

    The present PhD research was aimed at analysing the population structure of Staphylococcus aureus in China. Between 2000 and 2005 we found that patients from a single Chinese hospital showed increasing trends in antimicrobial resistance. Among methicillin-resistant S. aureus (MRSA), resistance again

  11. Sensitivity of Venturia inaequalis Chilean Isolates to Difenoconazole, Fenarimol, Mancozeb, and Pyrimethanil Sensibilidad de Aislados Chilenos de Venturia inaequalis a Difenoconazole, Fenarimol, Mancozeb y Pyrimethanil

    Directory of Open Access Journals (Sweden)

    Jose Luis Henríquez S

    2011-03-01

    Full Text Available Apple scab (Venturia inaequalis is the most important disease in Chilean apple (Malus domestica Borkh. orchards where fungicide management is the main tool to control disease. Sensitivity tests to difenoconazole, fenarimol, mancozeb, and pyrimethanil fungicides were conducted on V. inaequalis wild isolates to construct local baseline sensitivity distributions, and compare them with a collection of isolates from seven different commercial orchards with no evidence of practical resistance. In vitro assays were conducted and sensitivity was measured as inhibition of mycelial growth (difenoconazole, fenarimol, pyrimethanil or conidial germination (mancozeb. Departure from the baseline distribution to less sensitivity was found for difenoconazole, fenarimol, and mancozeb with resistance factors of 4.7, 5.8, and 2.1, respectively. The highest difference between baseline and orchard populations was observed for fenarimol which showed the highest shift to less sensitivity. Discriminatory doses of 0.04, 1.0, 0.6, and 0.2 µg mL-1 are proposed for in vitro monitoring of sensitivity to difenoconazole, fenarimol, mancozeb, and pyrimethanil, respectively.La sarna del manzano (Venturia inaequalis es la principal enfermedad del cultivo en Chile y es controlada principalmente con el uso de fungicidas. Se realizaron pruebas de sensibilidad a los fungicidas difenoconazole, fenarimol, mancozeb y pyrimethanil en aislados monoconidiales de cepas silvestres de V. inaequalis con el fin de elaborar curvas basales de sensibilidad y compararlas con la sensibilidad de una colección de aislados monoconidiales provenientes de siete huertos comerciales sin evidencias de resistencia práctica. Se realizaron pruebas in vitro donde la sensibilidad se midió como la inhibición del crecimiento miceliar (difenoconazole, fenarimol y pyrimethanil o la inhibición de la germinación de conidias (mancozeb. La población de huertos comerciales estudiada presentó una menor

  12. Genomic Analysis of Companion Rabbit Staphylococcus aureus

    Science.gov (United States)

    Holmes, Mark A.; Harrison, Ewan M.; Fisher, Elizabeth A.; Graham, Elizabeth M.; Parkhill, Julian; Foster, Geoffrey; Paterson, Gavin K.

    2016-01-01

    In addition to being an important human pathogen, Staphylococcus aureus is able to cause a variety of infections in numerous other host species. While the S. aureus strains causing infection in several of these hosts have been well characterised, this is not the case for companion rabbits (Oryctolagus cuniculus), where little data are available on S. aureus strains from this host. To address this deficiency we have performed antimicrobial susceptibility testing and genome sequencing on a collection of S. aureus isolates from companion rabbits. The findings show a diverse S. aureus population is able to cause infection in this host, and while antimicrobial resistance was uncommon, the isolates possess a range of known and putative virulence factors consistent with a diverse clinical presentation in companion rabbits including severe abscesses. We additionally show that companion rabbit isolates carry polymorphisms within dltB as described as underlying host-adaption of S. aureus to farmed rabbits. The availability of S. aureus genome sequences from companion rabbits provides an important aid to understanding the pathogenesis of disease in this host and in the clinical management and surveillance of these infections. PMID:26963381

  13. [Staphylococcus aureus and antibiotic resistance].

    Science.gov (United States)

    Sancak, Banu

    2011-07-01

    After the report of first case of methicillin-resistant Staphylococcus aureus (MRSA) in 1961, MRSA become a major problem worldwide. Over the last decade MRSA strains have emerged as serious pathogens in nosocomial and community settings. Glycopeptides (vancomycin and teicoplanin) are still the current mainstay of therapy for infections caused by MRSA. In the last decade dramatic changes have occurred in the epidemiology of MRSA infections. The isolates with reduced susceptibility and in vitro resistance to vancomycin have emerged. Recently, therapeutic alternatives such as quinupristin/dalfopristin, linezolid, tigecycline and daptomycin have been introduced into clinical practice for treating MRSA infections. Nevertheless, these drugs are only approved for certain indication and resistance has already been reported. In this review, the new information on novel drugs for treating MRSA infections and the resistance mechanisms of these drugs were discussed. PMID:21935792

  14. Exfoliative Toxins of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michal Bukowski

    2010-05-01

    Full Text Available Staphylococcus aureus is an important pathogen of humans and livestock. It causes a diverse array of diseases, ranging from relatively harmless localized skin infections to life-threatening systemic conditions. Among multiple virulence factors, staphylococci secrete several exotoxins directly associated with particular disease symptoms. These include toxic shock syndrome toxin 1 (TSST-1, enterotoxins, and exfoliative toxins (ETs. The latter are particularly interesting as the sole agents responsible for staphylococcal scalded skin syndrome (SSSS, a disease predominantly affecting infants and characterized by the loss of superficial skin layers, dehydration, and secondary infections. The molecular basis of the clinical symptoms of SSSS is well understood. ETs are serine proteases with high substrate specificity, which selectively recognize and hydrolyze desmosomal proteins in the skin. The fascinating road leading to the discovery of ETs as the agents responsible for SSSS and the characterization of the molecular mechanism of their action, including recent advances in the field, are reviewed in this article.

  15. The Heme Sensor System of Staphylococcus aureus

    OpenAIRE

    Stauff, Devin L; Skaar, Eric P.

    2009-01-01

    The important human pathogen Staphylococcus aureus is able to satisfy its nutrient iron requirement by acquiring heme from host hemoglobin in the context of infection. However, heme acquisition exposes S. aureus to heme toxicity. In order to detect the presence of toxic levels of exogenous heme, S. aureus is able to sense heme through the heme sensing system (HssRS) two-component system. Upon sensing heme, HssRS directly regulates the expression of the heme-regulated ABC transporter HrtAB, wh...

  16. Staphylococcus aureus infections in psittacine birds.

    Science.gov (United States)

    Hermans, K; Devriese, L A; De Herdt, P; Godard, C; Haesebrouck, F

    2000-10-01

    Staphylococcus aureus was isolated from internal organs of 13 different psittacine birds submitted for necropsy over a period of 6 years. The birds all had lesions consistent with septicaemia. S. aureus isolates included three different phage types. In seven of the 13 birds, concurrent infections with Chlamydophila species, Enterococcus hirae, Candida species, unidentified streptococci and coagulasenegative staphylococci were detected. One bird also had lesions of lymphoid leucosis. Few indications were found that staphylococcosis associated problems may spread epidemically. The present studies suggest that S. aureus is pathogenic for psittacine birds, although it does not seem to be a frequent cause of disease. PMID:19184832

  17. Laboratory Maintenance of Methicillin-Resistant Staphylococcus aureus (MRSA)

    OpenAIRE

    Nicholas P Vitko; Richardson, Anthony R.

    2013-01-01

    Staphylococcus aureus is an important bacterial pathogen in the hospital and community settings, especially Staphylococcus aureus clones that exhibit methicillin-resistance (MRSA). Many strains of S. aureus are utilized in the laboratory, underscoring the genetic differences inherent in clinical isolates. S. aureus grows quickly at 37°C with aeration in rich media (e.g. BHI) and exhibits a preference for glycolytic carbon sources. Furthermore, S. aureus has a gold pigmentation, exhibits β-hem...

  18. Degradación de tiocianato por hongos aislados de ambientes mineros y evaluación de su capacidad degradativa

    Directory of Open Access Journals (Sweden)

    Susan Medina

    2012-10-01

    Full Text Available El Perú es uno de los principales países en la extracción de minerales como el oro, zinc, plomo y estaño. En la producción de oro se utiliza cianuro, el cual es tóxico para el medio ambiente, y que por reacción natural con el azufre se convierte en tiocianato (-SCN. En el presente trabajo se aislan hongos con capacidad de degradar tiocianato procedentes de aguas y suelos de zonas mineras de Junín y Tumbes. Estas cepas se sometieron a ensayos con concentraciones de tiocianato entre 5 y 600 mM. Asimismo, se evaluó la cinética de degradación de tiocianato en medio Kwon partiendo de 1,2 g.L-1 de KSCN y luego se realizó la identificación morfológica. De un total de 58 mohos aislados, obtuvimos 4 mohos con excelentes capacidades de degradar tiocianato y que pueden ser utilizados en biorremediación. La capacidad degradativa de estas cepas fue en promedio 10,05 mg.L-1 de -SCN con una velocidad de 28,77 mg.L-1.h-1. Dos cepas fueron identificadas fenotípica y molecularmente como Fusarium trincictum usando el marcador ITS del gen rDNA.

  19. The Heme Sensor System of Staphylococcus aureus

    Science.gov (United States)

    Stauff, Devin L.; Skaar, Eric P.

    2016-01-01

    The important human pathogen Staphylococcus aureus is able to satisfy its nutrient iron requirement by acquiring heme from host hemoglobin in the context of infection. However, heme acquisition exposes S. aureus to heme toxicity. In order to detect the presence of toxic levels of exogenous heme, S. aureus is able to sense heme through the heme sensing system (HssRS) two-component system. Upon sensing heme, HssRS directly regulates the expression of the heme-regulated ABC transporter HrtAB, which alleviates heme toxicity. Importantly, the inability to sense or respond to heme alters the virulence of S. aureus, highlighting the importance of heme sensing and detoxification to staphylococcal pathogenesis. Furthermore, potential orthologues of the Hss and Hrt systems are found in many species of Gram-positive bacteria, a possible indication that heme stress is a challenge faced by bacteria whose habitats include host tissues rich in heme. PMID:19494582

  20. Binding of heparan sulfate to Staphylococcus aureus.

    OpenAIRE

    Liang, O D; Ascencio, F; Fransson, L A; Wadström, T

    1992-01-01

    Heparan sulfate binds to proteins present on the surface of Staphylococcus aureus cells. Binding of 125I-heparan sulfate to S. aureus was time dependent, saturable, and influenced by pH and ionic strength, and cell-bound 125I-heparan sulfate was displaced by unlabelled heparan sulfate or heparin. Other glycosaminoglycans of comparable size (chondroitin sulfate and dermatan sulfate), highly glycosylated glycoprotein (hog gastric mucin), and some anionic polysaccharides (dextran sulfate and RNA...

  1. The Staphylococcus aureus “superbug”

    OpenAIRE

    FOSTER, TIMOTHY JAMES

    2004-01-01

    PUBLISHED There has been some debate about the disease-invoking potential of Staphylococcus aureus strains and whether invasive disease is associated with particularly virulent genotypes, or "superbugs." A study in this issue of the JCI describes the genotyping of a large collection of nonclinical, commensal S. aureus strains from healthy individuals in a Dutch population. Extensive study of their genetic relatedness by amplified restriction fragment typing and comparison with strains that...

  2. Transmissible mupirocin resistance in Staphylococcus aureus.

    OpenAIRE

    Rahman, M.; Noble, W. C.; Cookson, B

    1989-01-01

    The spread of two strains of Staphylococcus aureus with high level resistance to mupirocin is described. The resistance proved to be easily transferred to other S. aureus strains by filter mating experiments and on the skin of mice. No plasmid band corresponding to the resistance could be demonstrated by agarose gel electrophoresis or by caesium chloride gradient centrifugation but cleavage of 'chromosomal' DNA from resistant recipients showed bright bands of DNA absent from sensitive controls.

  3. Triclosan Promotes Staphylococcus aureus Nasal Colonization

    OpenAIRE

    Syed, Adnan K.; Ghosh, Sudeshna; Love, Nancy G.; Boles, Blaise R.

    2014-01-01

    ABSTRACT The biocide triclosan is used in many personal care products, including toothpastes, soaps, clothing, and medical equipment. Consequently, it is present as a contaminant in the environment and has been detected in some human fluids, including serum, urine, and milk. Staphylococcus aureus is an opportunistic pathogen that colonizes the noses and throats of approximately 30% of the population. Colonization with S. aureus is known to be a risk factor for several types of infection. Here...

  4. Prevalencia de Staphylococcus aureus resistente a meticilina en infecciones de piel y partes blandas en pacientes ambulatorios

    Directory of Open Access Journals (Sweden)

    Verónica Bermejo

    2012-08-01

    Full Text Available Recientemente se ha observado un aumento en la prevalencia de Staphylococcus aureus resistente a la meticilina (SAMR en pacientes ambulatorios con infecciones de piel y partes blandas (IPyPB. Los datos epidemiológicos locales disponibles son limitados. Se realizó un estudio descriptivo, prospectivo, de consultantes con IPyPB en la División Infectología del Hospital General de Agudos Juan A. Fernández, en el período 01/10/2009 a 31/01/2011. Fueron 130; edad mediana 36 años (RIC 25.9-43.5; hombres 61.5%. El 46.9% era HIV+. Cien cultivos (76.9%, de 100 pacientes, resultaron positivos: 83 S. aureus, 8 Streptococcus spp. y 9 con otros microorganismos. De los S. aureus aislados, 62 (74.7% fueron resistentes a oxacilina, 12 (14.4% a clindamicina, 14 (16.9% a eritromicina, 5 (6% a ciprofloxacina, presentando en algunos casos más de una resistencia. Todos fueron sensibles a rifampicina y minociclina, y 98.8% (82 a trimetoprima-sulfametoxazol. El 83.8% (52 de los pacientes con SAMR tenían algún factor de riesgo (FR, sin diferencias con los pacientes con otros aislamientos. La presentación clínica más frecuente de IPyPB / SAMR fue forunculosis: 56.4 (35/62 vs. 28.9% (11/38 en infecciones por otros microorganismos (p = 0.013. La resistencia a oxacilina fue similar entre pacientes HIV+ y negativos (79.1 vs. 70%, p = 0.179 (34/43 vs. 28/40. Concluimos que en la población estudiada se encontró una alta prevalencia de SAMR, independientemente de la serología para HIV o la presencia de FR. Las opciones de tratamiento empírico para este microorganismo son minociclina y trimetoprima-sulfametoxazol.

  5. Prevalencia de Staphylococcus aureus resistente a meticilina en infecciones de piel y partes blandas en pacientes ambulatorios Prevalence of methicillin resistant Staphylococcus aureus in skin and soft tissue infections, in ambulatory patients

    Directory of Open Access Journals (Sweden)

    Verónica Bermejo

    2012-08-01

    Full Text Available Recientemente se ha observado un aumento en la prevalencia de Staphylococcus aureus resistente a la meticilina (SAMR en pacientes ambulatorios con infecciones de piel y partes blandas (IPyPB. Los datos epidemiológicos locales disponibles son limitados. Se realizó un estudio descriptivo, prospectivo, de consultantes con IPyPB en la División Infectología del Hospital General de Agudos Juan A. Fernández, en el período 01/10/2009 a 31/01/2011. Fueron 130; edad mediana 36 años (RIC 25.9-43.5; hombres 61.5%. El 46.9% era HIV+. Cien cultivos (76.9%, de 100 pacientes, resultaron positivos: 83 S. aureus, 8 Streptococcus spp. y 9 con otros microorganismos. De los S. aureus aislados, 62 (74.7% fueron resistentes a oxacilina, 12 (14.4% a clindamicina, 14 (16.9% a eritromicina, 5 (6% a ciprofloxacina, presentando en algunos casos más de una resistencia. Todos fueron sensibles a rifampicina y minociclina, y 98.8% (82 a trimetoprima-sulfametoxazol. El 83.8% (52 de los pacientes con SAMR tenían algún factor de riesgo (FR, sin diferencias con los pacientes con otros aislamientos. La presentación clínica más frecuente de IPyPB / SAMR fue forunculosis: 56.4 (35/62 vs. 28.9% (11/38 en infecciones por otros microorganismos (p = 0.013. La resistencia a oxacilina fue similar entre pacientes HIV+ y negativos (79.1 vs. 70%, p = 0.179 (34/43 vs. 28/40. Concluimos que en la población estudiada se encontró una alta prevalencia de SAMR, independientemente de la serología para HIV o la presencia de FR. Las opciones de tratamiento empírico para este microorganismo son minociclina y trimetoprima-sulfametoxazol.An increased prevalence of community-acquired methicillin resistant Staphylococcus aureus (MRSA in skin and soft tissue infections (SSTI has been recently reported. Epidemiological data in Argentina is limited. Our objectives were to evaluate etiological agents, clinical presentation, risk factors and evolution of SSTI in ambulatory patients, in a

  6. Potassium Uptake Modulates Staphylococcus aureus Metabolism.

    Science.gov (United States)

    Gries, Casey M; Sadykov, Marat R; Bulock, Logan L; Chaudhari, Sujata S; Thomas, Vinai C; Bose, Jeffrey L; Bayles, Kenneth W

    2016-01-01

    As a leading cause of community-associated and nosocomial infections, Staphylococcus aureus requires sophisticated mechanisms that function to maintain cellular homeostasis in response to its exposure to changing environmental conditions. The adaptation to stress and maintenance of homeostasis depend largely on membrane activity, including supporting electrochemical gradients and synthesis of ATP. This is largely achieved through potassium (K(+)) transport, which plays an essential role in maintaining chemiosmotic homeostasis, affects antimicrobial resistance, and contributes to fitness in vivo. Here, we report that S. aureus Ktr-mediated K(+) uptake is necessary for maintaining cytoplasmic pH and the establishment of a proton motive force. Metabolite analyses revealed that K(+) deficiency affects both metabolic and energy states of S. aureus by impairing oxidative phosphorylation and directing carbon flux toward substrate-level phosphorylation. Taken together, these results underline the importance of K(+) uptake in maintaining essential components of S. aureus metabolism. IMPORTANCE Previous studies describing mechanisms for K(+) uptake in S. aureus revealed that the Ktr-mediated K(+) transport system was required for normal growth under alkaline conditions but not under neutral or acidic conditions. This work focuses on the effect of K(+) uptake on S. aureus metabolism, including intracellular pH and carbon flux, and is the first to utilize a pH-dependent green fluorescent protein (GFP) to measure S. aureus cytoplasmic pH. These studies highlight the role of K(+) uptake in supporting proton efflux under alkaline conditions and uncover a critical role for K(+) uptake in establishing efficient carbon utilization. PMID:27340697

  7. Dinámica poblacional del rotífero Brachionus ibericus aislado de estanques para camarón, alimentado con diferentes dietas

    Directory of Open Access Journals (Sweden)

    José Cristóbal Román-Reyes

    2014-11-01

    Full Text Available La producción de microalgas vivas para cultivar rotíferos constituye uno de los mayores costos de operación en la larvicultura de peces, por lo que se están desarrollando sustitutos comerciales de microalgas para la alimentación y producción de rotíferos. Se desconoce el efecto que tienen las formulaciones comerciales sobre la dinámica poblacional de rotíferos nativos del noroeste de México y en este estudio se evaluó el efecto de cuatro dietas comerciales (Espirulina, RotiMac®, Nanno 3600®, RotiGrow-Plus® y la microalga viva Nannochloropsis sp., sobre el crecimiento poblacional y fecundidad del rotífero Brachionus ibericus (GenBank KJ949043, aislado de una granja de camarón blanco (Litopenaeus vannamei. Se realizaron cinco réplicas por tratamiento alimenticio utilizando recipientes con volumen de 12 L de agua, con temperatura de 29 ± 1°C y salinidad de 35 ± 1, respectivamente. Los resultados mostraron que durante los periodos experimentales, las dietas probadas resultaron adecuadas para alimentar a B. ibericus, con tasas de crecimiento, tiempos de duplicación, densidades máximas y fecundidades que fluctuaron entre 0.20 a 0.27 rotíferos día-1, 2.60 a 3.42 días, 215 a 344 rotíferos mL-1 y de 0.16 a 0.39 huevos hembra-1, respectivamente. Las diferencias entre tratamientos fueron significativas (P 0.05 a las obtenidas con Nanno 3600®.

  8. Intra-cellular Staphylococcus aureus alone causes infection in vivo

    Directory of Open Access Journals (Sweden)

    T Hamza

    2013-07-01

    Full Text Available Chronic and recurrent bone infections occur frequently but have not been explained. Staphylococcus aureus (S. aureus is often found among chronic and recurrent infections and may be responsible for such infections. One possible reason is that S. aureus can internalize and survive within host cells and by doing so, S. aureus can evade both host defense mechanisms and most conventional antibiotic treatments. In this study, we hypothesized that intra-cellular S. aureus could induce infections in vivo. Osteoblasts were infected with S. aureus and, after eliminating extra-cellular S. aureus, inoculated into an open fracture rat model. Bacterial cultures and radiographic observations at post-operative day 21 confirmed local bone infections in animals inoculated with intra-cellular S. aureus within osteoblasts alone. We present direct in vivo evidence that intra-cellular S. aureus could be sufficient to induce bone infection in animals; we found that intra-cellular S. aureus inoculation of as low as 102 colony forming units could induce severe bone infections. Our data may suggest that intra-cellular S. aureus can “hide” in host cells during symptom-free periods and, under certain conditions, they may escape and lead to infection recurrence. Intra-cellular S. aureus therefore could play an important role in the pathogenesis of S. aureus infections, especially those chronic and recurrent infections in which disease episodes may be separated by weeks, months, or even years.

  9. Caracterización de aislados de rizobios provenientes de nódulos de soya (Glycine max (L.) Merril) con potencialidades en la promoción del crecimiento vegetal

    OpenAIRE

    Ionel Hernández Forte; María C. Nápoles García; Belkis Morales Mena

    2015-01-01

    El objetivo del presente trabajo fue caracterizar cuatro aislados de rizobios y la cepa Bradyrhizobium elkanii ICA 8001 provenientes de nódulos de plantas de soya, en cuanto a su capacidad para exhibir tres atributos positivos que caracterizan estas rizobacterias promotoras del crecimiento vegetal. Se determinó su capacidad de producir sideróforos; AIA (ácido 3-indolacético) y la actividad específica de la enzima 1-aminociclopropano-1- ácido carboxílico (ACC) desaminasa. Solo el aisl...

  10. Generación eléctrica mediante un sistema híbrido hidráulico-fotovoltaico aislado de la red para una pequeña población rural

    OpenAIRE

    Visiga Delgado, Daniel

    2009-01-01

    El objeto del proyecto es el diseño de un sistema, factible tecnológicamente, híbrido hidráulicofotovoltaico, aislado de la red para una pequeña población rural. Este sistema está dimensionado a partir de un río tipo y recibe el apoyo de un sistema fotovoltaico y un tanque de baterías. Por otro lado, el proyecto tiene la finalidad de crear una demanda escalable unitaria base para una vivienda rural tipo y, a partir de la cual, obtener la demanda de la población.

  11. Evaluación de la ampliación de ALUAR con el SIP aislado e interconectado al SADI : Parte 1: aspectos generales y estabilidad dinámica

    OpenAIRE

    Agüero, Jorge Luis; Beroqui, Mario César; Barbieri, María Beatriz; Macchione, Luis; Cosatti, Oscar

    2005-01-01

    Se presenta una descripción de los tipos de estudios realizados, modelos utilizados y simulaciones de comportamiento efectuados para evaluar el efecto de la ampliación de la planta de Aluar sobre el SIP aislado y sobre el SADI-SIP interconectados. El objetivo de los estudios es la definición básica de las nuevas instalaciones, la adecuación de las existentes, la definición del equipamiento de control y los recursos estabilizantes requeridos, y la posible modificación de los recursos post f...

  12. Caracterización de especies y perfil de resistencia antimicrobiana en enterococos aislados de alimentos de origen animal provenientes de un área rural del centro de la provincia de Buenos Aires, Argentina

    OpenAIRE

    Delpech, Gastón

    2014-01-01

    El objetivo general de esta investigación fue caracterizar fenotípicamente y determinar el perfil de resistencia in vitro de especies de enterococos aislados de alimentos de origen animal provenientes de un área rural del Centro de la Provincia de Buenos Aires, Argentina. Durante el período 2009-2012 se analizaron N = 1937 muestras de carne picada (n = 1080), salamines artesanales (n = 642), quesos de vaca (n = 119), quesos de cabra (n = 42), leche de cabra (n = 30) y queso de oveja (n = 2...

  13. Mantenimiento en cultivo y caracterización de un microsporidio (Encephalitozoon hellem aislado en un paciente con Sida y neumonía MANTAINED IN CULTURE AND CHARACTERIZATION OF A MICROSPORIDIAN (Encephalitozoon hellem ISOLATED FROM AIDS PATIENT WITH NEUMONIA

    Directory of Open Access Journals (Sweden)

    FERNANDO J. BORNAY-LLINARES

    2000-07-01

    Full Text Available Comunicamos la identificación, a nivel de especie, de un microsporidio aislado en cultivo celular a partir de un lavado broncoalveolar de un paciente con Sida y neumonía. La caracterización del aislado se realizó mediante: 1 estudio morfológico utilizando métodos de microscopía óptica y electrónica, 2 estudio inmunológico con antisueros específicos, inmunofluorescencia indirecta (IFI e inmunoblot (WB y 3 estudio molecular tras reacción en cadena de la polimerasa (PCR con iniciadores especie-específicos diseñados a partir de la región que codifica la subunidad menor del ARN ribosomal. Las características ultraestructurales del aislado permitieron su identificación en el género Encephalitozoon. La identificación específica del microsporidio como Encephalito-zoon hellem se realizó mediante IFI y WB, empleando suero policlonal de conejo anti-E. hellem (CDC:0291:V213, y mediante la amplificación por PCR del fragmento diagnóstico utilizando el par de iniciadores EHELF/EHELR específicos para esta especie. El aislado ha sido denominado EHVS-96 y se mantiene en cultivo continuo en células Vero-E6. Este es el primer aislamiento en cultivo y caracterización de E. hellem en España.We report the identification to the species level of a microsporidian isolated from the bronchoalveolar lavage of an AIDS patient in Spain. Characterization of the isolate was performed by: 1 morphological methods using optical and electron microscopy; 2 immunological methods such as immunofluorescence assay (IIF and immunoblot (WB using specific antiserum and, 3 polymerase chain reaction (PCR using species-specific primers designed on the coding region of the small subunit of the ribosomal RNA gene. Ultrastructural features allowed the identification of the isolate as belonging to the Encephalitozoon genus. Species identification as Encephalitozoon hellem was achieved by IIF and WB using polyc lonal rabbit serum anti-E. hellem (CDC:0291:V213, as well as

  14. Antimicrobial (Drug) Resistance: Methicillin-Resistant Staphylococcus aureus (MRSA)

    Science.gov (United States)

    ... Marketing Share this: Main Content Area Methicillin-Resistant Staphylococcus aureus (MRSA) During the past four decades, methicillin-resistant Staphylococcus aureus , or MRSA, has evolved from a controllable ...

  15. Evolution of methicillin-resistant Staphylococcus aureus towards increasing resistance

    DEFF Research Database (Denmark)

    Strommenger, Birgit; Bartels, Mette Damkjær; Kurt, Kevin;

    2014-01-01

    To elucidate the evolutionary history of Staphylococcus aureus clonal complex (CC) 8, which encompasses several globally distributed epidemic lineages, including hospital-associated methicillin-resistant S. aureus (MRSA) and the highly prevalent community-associated MRSA clone USA300....

  16. Classification of Healthcare-Associated Staphylococcus aureus Bacteremia

    DEFF Research Database (Denmark)

    Smit, Jesper; Søgaard, Mette; Schønheyder, Henrik Carl; Nielsen, Henrik; Thomsen, Reimar Wernich

    2016-01-01

    We investigated whether different definitions of healthcare-associated infection influenced the prevalence, characteristics, and mortality of patients with Staphylococcus aureus bacteremia. With different definitions, the proportion of patients classified as having healthcare-associated S. aureus...

  17. Comparative Efficacy of Ceftaroline with Linezolid against Staphylococcus Aureus and Methicillin Resistant Staphylococcus Aureus

    International Nuclear Information System (INIS)

    Objective:To compare the in vitro antimicrobial efficacy of ceftaroline with linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus. Study Design: Quasi-experimental study. Place and Duration of Study: Microbiology Department, Army Medical College, Rawalpindi, from January to December 2013. Methodology: Clinical samples from respiratory tract, blood, pus and various catheter tips routinely received in the Department of Microbiology, Army Medical College, Rawalpindi were innoculated on blood and MacConkey agar. Staphylococcus aureus was identified by colony morphology, Gram reaction, catalase test and coagulase test. Methicillin resistant Staphylococcus aureus detection was done by modified Kirby Bauer disc diffusion method using cefoxitin disc (30g) and the isolates were considered methicillin resistant if the zone of inhibition around cefoxitin disc was /sup 2/ 21 mm. Bacterial suspensions of 56 Staphylococcus aureus isolates and 50 MRSA isolates were prepared, which were standardized equal to 0.5 McFarland's turbidity standard and inoculated on Mueller-Hinton agar plates followed by application of ceftaroline and linezolid disc (Oxoid, UK), according to manufacturer's instructions. The plates were then incubated at 37 Degree C aerobically for 18 - 24 hours. Diameters of inhibition zone were measured and interpretated as per Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Out of 106 isolates all of the 56 Staphylococcus aureus (100%) were sensitive to ceftaroline and linezolid. However, out of 50 methicillin resistant Staphylococcus aureus, 48 (96%) were sensitive to ceftaroline whereas, 49 (98%) were sensitive to linezolid. Conclusion: Ceftaroline is equally effective as linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus. (author)

  18. Characterization of a Mouse-Adapted Staphylococcus aureus Strain

    OpenAIRE

    Holtfreter, Silva; Fiona J Radcliff; Grumann, Dorothee; Read, Hannah; Johnson, Sarah; Monecke, Stefan; Ritchie, Stephen; Clow, Fiona; Goerke, Christiane; Bröker, Barbara M.; Fraser, John D.; Wiles, Siouxsie

    2013-01-01

    More effective antibiotics and a protective vaccine are desperately needed to combat the ‘superbug’ Staphylococcus aureus. While in vivo pathogenicity studies routinely involve infection of mice with human S. aureus isolates, recent genetic studies have demonstrated that S. aureus lineages are largely host-specific. The use of such animal-adapted S. aureus strains may therefore be a promising approach for developing more clinically relevant animal infection models. We have isolated a mouse-ad...

  19. Meticillin-resistant Staphylococcus aureus (MRSA)

    DEFF Research Database (Denmark)

    Stefani, Stefania; Chung, Doo Ryeon; Lindsay, Jodi A;

    2012-01-01

    This article reviews recent findings on the global epidemiology of healthcare-acquired/associated (HA), community-acquired/associated (CA) and livestock-associated (LA) meticillin-resistant Staphylococcus aureus (MRSA) and aims to reach a consensus regarding the harmonisation of typing methods...... health. Continuous efforts to understand the changing epidemiology of S. aureus infection in humans and animals are therefore necessary, not only for appropriate antimicrobial treatment and effective infection control but also to monitor the evolution of the species. The group made several consensus...

  20. A sensitive assay for Staphylococcus aureus nucleases

    International Nuclear Information System (INIS)

    A sensitive assay for staphylococcal nuclease involving incubation of the enzyme sample with heat-denatured [3H] thymidine labelled DNA from E.coli, precipitation with trichloroacetic acid and measurement of the radioactivity of acid-soluble nucleotides released has been developed. The assay is sensitive enough to be used for comparing the levels of nucleases elaborated by different strains of S. aureus as well as for determining the extent of contamination of S. aureus in food and water samples even at levels at which the conventional spectrophotometric and toluidine blue-DNA methods are totally inadequate. (author). 26 refs., 3 figs ., 3 tabs

  1. Staphylococcus aureus bacteremia in hemodialysis patients.

    Science.gov (United States)

    Latos, D L; Stone, W J; Alford, R H

    1977-01-01

    Fifteen male hemodialysis patients developed 21 episodes of S. aureus bacteremia. Infections involving vascular access were responsible for 65% of initial bacteremias. The arteriovenous fistula was the most prevalent type of access used, and thus was responsible for the majority of these illnesses. Phage typing indicated that recurrent episodes were due to reinfection rather than relapse. Complications included endocarditis, osteomyelitis, septic embolism, and pericarditis. One patient died of infectious complications. It is recommended that hemodialysis patients developing bacteremia due to S. aureus receive at least 6 weeks of beta lactamase-resistant antimicrobial therapy. PMID:608860

  2. 21 CFR 866.3700 - Staphylococcus aureus serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Staphylococcus aureus serological reagents. 866... Staphylococcus aureus serological reagents. (a) Identification. Staphylococcus aureus serological reagents are... diagnosis of disease caused by this bacterium belonging to the genus Staphylococcus and...

  3. 9 CFR 113.115 - Staphylococcus Aureus Bacterin-Toxoid.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Staphylococcus Aureus Bacterin-Toxoid... REQUIREMENTS Inactivated Bacterial Products § 113.115 Staphylococcus Aureus Bacterin-Toxoid. Staphylococcus... Staphylococcus aureus which has been inactivated and is nontoxic. Each serial of biological product...

  4. A pig model of acute Staphylococcus aureus induced pyemia

    DEFF Research Database (Denmark)

    Nielsen, O. L.; Iburg, T.; Aalbæk, B.;

    2009-01-01

    Background: Sepsis caused by Staphylococcus aureus constitutes an important cause of morbidity and mortality in humans, and the incidence of this disease-entity is increasing. In this paper we describe the initial microbial dynamics and lesions in pigs experimentally infected with S. aureus....... aureus isolated from man and an extension of the timeframe aiming at inducing sepsis, severe sepsis and septic shock....

  5. Multidrug-Resistant Staphylococcus aureus in US Meat and Poultry

    OpenAIRE

    Waters, Andrew E.; Contente-Cuomo, Tania; Buchhagen, Jordan; Liu, Cindy M.; Watson, Lindsey; Pearce, Kimberly; Foster, Jeffrey T.; Bowers, Jolene; Driebe, Elizabeth M; Engelthaler, David M.; Keim, Paul S; Lance B Price

    2011-01-01

    We characterized the prevalence, antibiotic susceptibility profiles, and genotypes of Staphylococcus aureus among US meat and poultry samples (n = 136). S. aureus contaminated 47% of samples, and multidrug resistance was common among isolates (52%). S. aureus genotypes and resistance profiles differed significantly among sample types, suggesting food animal–specific contamination.

  6. Risk factors for Staphylococcus aureus and methicillin-resistant S aureus colonization among health care workers in pediatrics departments.

    Science.gov (United States)

    Gomes, Ivete Martins; Marlow, Mariel Asbury; Pinheiro, Marcos Gabriel; de Freitas, Maria de Fátima Nogueira; Fonseca, Fernanda Fernandes; Cardoso, Claudete Aparecida Araújo; Aguiar-Alves, Fábio

    2014-08-01

    Risk factors for Staphylococcus aureus and methicillin-resistant S aureus (MRSA) were evaluated for 178 health care workers from a public hospital pediatrics department in Brazil. Colonization rates were 33.1% for S aureus and 5.1% for MRSA. Risk factors for S aureus colonization differed from those for MRSA. Results suggest nurses with prolonged pediatric patient contact in inpatient units are at higher risk for MRSA colonization. PMID:25087145

  7. Contribución al conocimiento de la biología y taxonomía de un hongo del género Phytium aislado del "aliso", Alnus acuminata HBK Contribución al conocimiento de la biología y taxonomía de un hongo del género Phytium aislado del "aliso", Alnus acuminata HBK

    Directory of Open Access Journals (Sweden)

    Cabrera Orlando

    1990-06-01

    Full Text Available

    Se estudio la biología de un hongo aislado de la parte externa de nódulos de raíces de aliso (Alnus acumi"ata HB K, el cual presento un alto poder de germinación a bajas temperaturas (entre QOC y 4QC, condición que le confiere gran agresividad para colonizar el suelo, de tal forma que se constituye en un factor importante en la ecofisiología de las poblaciones de aliso que crecen en los bosques secundarios del sub-paramo. A partir de cultivos puros se hicieron estudios para su identificación.

    Some biological aspects of an isolated fungus of Alnus acuminata roots were studied. It bas been found Tbat between OOC and 4°C tbe fungi grows fast. This condition can result in a important factor in the ecophysiology of 'Aliso' populations, that grows in secondary forests at sub-paramo, After a review of the taxonomic literature, we placed it in the Phytium genus, but not in a particular described species. We assume that it is a new species. We modificated the microculture technique that was simpler and safer and them we made direct observations about tbe fungus growtb and development. As for now it is nominated as Phytiun near Mammillatum Meurs. Palabras Claves: Phytium, bongos, A/nus acuminata HBK., "Aliso".

  8. Common R-plasmids in Staphylococcus aureus and Staphylococcus epidermidis during a nosocomial Staphylococcus aureus outbreak.

    OpenAIRE

    Cohen, M. L.; Wong, E. S.; Falkow, S

    1982-01-01

    During a 7-month period in 1978 to 1979, 31 patients and personnel at a Kentucky hospital were colonized or infected with a Staphylococcus aureus strain resistant to clindamycin, erythromycin, gentamicin, methicillin, penicillin, and tetracycline. S. epidermidis with similar antibiotic resistance patterns had been isolated in this hospital in the year before the S. aureus outbreak. A 32-megadalton R-plasmid, pUW3626, mediating resistance to penicillin and gentamicin, was present in these isol...

  9. Staphylococcus aureus resistente a la meticilina (SARM)

    Centers for Disease Control (CDC) Podcasts

    2007-10-22

    Datos importantes sobre las infecciones por SARM en Estados Unidos, en las escuelas y los entornos médicos. (Title: Methicillin-resistant Staphylococcus aureus (MRSA)Created: 10/2007).  Created: 10/22/2007 by National Center for Preparedness, Detection, and Control of Infectious Diseases.   Date Released: 11/9/2007.

  10. Staphylococcus aureus enterotoxins A- and B

    DEFF Research Database (Denmark)

    Danielsen, E Michael; Hansen, Gert H; Karlsdóttir, Edda

    2013-01-01

    Enterotoxins of Staphylococcus aureus are among the most common causes of food poisoning. Acting as superantigens they intoxicate the organism by causing a massive uncontrolled T cell activation that ultimately may lead to toxic shock and death. In contrast to our detailed knowledge regarding...

  11. Staphylococcus aureus vaccines: Deviating from the carol.

    Science.gov (United States)

    Missiakas, Dominique; Schneewind, Olaf

    2016-08-22

    Staphylococcus aureus, a commensal of the human nasopharynx and skin, also causes invasive disease, most frequently skin and soft tissue infections. Invasive disease caused by drug-resistant strains, designated MRSA (methicillin-resistant S. aureus), is associated with failure of antibiotic therapy and elevated mortality. Here we review polysaccharide-conjugate and subunit vaccines that were designed to prevent S. aureus infection in patients at risk of bacteremia or surgical wound infection but failed to reach their clinical endpoints. We also discuss vaccines with ongoing trials for combinations of polysaccharide-conjugates and subunits. S. aureus colonization and invasive disease are not associated with the development of protective immune responses, which is attributable to a large spectrum of immune evasion factors. Two evasive strategies, assembly of protective fibrin shields via coagulases and protein A-mediated B cell superantigen activity, are discussed as possible vaccine targets. Although correlates for protective immunity are not yet known, opsonophagocytic killing of staphylococci by phagocytic cells offers opportunities to establish such criteria. PMID:27526714

  12. Carriage of Staphylococcus aureus in the elderly

    NARCIS (Netherlands)

    R. M. Parnaby; G. O'Dwyer; H. A. Monsey; M. S. Shafi

    1996-01-01

    textabstractThe point prevalence and incidence of Staphylococcus aureus (methicillin-sensitive and -resistant) carriage by inpatients on acute elderly care wards was estimated. The relationship to body site and to previous admissions to hospital or other institutions was determined. Fifty-five patie

  13. Increasing resistance of Staphylococcus aureus to ciprofloxacin.

    OpenAIRE

    Daum, T E; Schaberg, D R; Terpenning, M S; Sottile, W S; Kauffman, C A

    1990-01-01

    We demonstrated the marked emergence of resistance to ciprofloxacin among Staphylococcus arueus strains isolated at the Ann Arbor Veterans Administration Medical Center. All S. aureus isolates tested from 1984 to 1985 were susceptible, whereas 55.1% of methicillin-resistant and 2.5% of methicillin-susceptible strains from 1989 had high-level resistance to ciprofloxacin.

  14. Staphylococcus aureus spa type t437

    DEFF Research Database (Denmark)

    Glasner, C; Pluister, G; Westh, H;

    2015-01-01

    large epidemiological studies in Europe. Nevertheless, the overall numbers identified in some Northern European reference laboratories have increased during the past decade. To determine whether the S. aureus t437 clone is present in other European countries, and to assess its genetic diversity across...

  15. Relationship between Vancomycin-Resistant Staphylococcus aureus, Vancomycin-Intermediate S. aureus, High Vancomycin MIC, and Outcome in Serious S. aureus Infections

    OpenAIRE

    Holmes, Natasha E.; Johnson, Paul D. R.; Howden, Benjamin P.

    2012-01-01

    Vancomycin has been used successfully for over 50 years for the treatment of Staphylococcus aureus infections, particularly those involving methicillin-resistant S. aureus. It has proven remarkably reliable, but its efficacy is now being questioned with the emergence of strains of S. aureus that display heteroresistance, intermediate resistance, and, occasionally, complete vancomycin resistance. More recently, an association has been established between poor outcome and infections with strain...

  16. Caracterización de actinobacterias raras, degradadoras de lignocelulosa: demostración de actividad lacasa en dos aislados de Tsukamurella sp y Cellulosimicrobium sp

    Directory of Open Access Journals (Sweden)

    Enrique Luis Revollo Escudero

    2014-01-01

    Full Text Available Título en ingles: Characterization of lignocelluloses-degrading rare actinobacteria: Demostration of laccase activity in two isolates of Tsukamurella sp and Cellulosimicrobium sp Resumen: Las características fisicoquímicas de la lignina y su compactación con la celulosa han dificultado la explotación biotecnológica de enormes cantidades de biomasa vegetal. Las lacasas constituyen una subfamilia de oxidasas multicobre que intervienen en la despolimerización de la lignina. Si bien han sido ampliamente caracterizadas en los hongos, los estudios de la diversidad y las funcionalidades de las lacasas en los procariotas se han centrado especialmente en isoformas enzimáticas de Streptomyces sp. En este trabajo se aislaron 20 cepas de actinobacterias del suelo. La actividad lacasa de 17 de ellas fue evidenciada en ensayos cualitativos con guayacol y dos cepas seleccionadas fueron caracterizadas en detalle. Las pruebas morfológicas y el análisis de las secuencias del gen 16S rRNA apuntan a que estos dos aislados pertenecen a los géneros Tsukamurella y Cellulosimicrobium. En cultivo sumergido con agitación, AC01 (Tsukamurella sp. expresó una máxima actividad de oxidación de ABTS (2,2’-azino-bis-(3-etilbenzotiazolin-6-sulfonato de 108 U/L. Por otra parte, AC18 (Cellulosimicrobium sp. que había exhibido una actividad oxidativa de guayacol superior a las 16 cepas restantes y demostró ser resistente a niveles tóxicos de cobre, logró un valor máximo de oxidación del ABTS de 0,56 U/L. Estos resultados sugieren que en el aislado AC18 operaría un fenómeno de especificidad de sustrato o de inductor, regulador de la expresión y de la actividad lacasa cuantificable. La caracterización genómica y funcional de las lacasas de nuevas actinobacterias lignocelulósicas ampliará la gama de centros redox con aplicaciones biotecnológicas específicas, además de facilitar el establecimiento de sus relaciones evolutivas con las eucariotas

  17. Staphylococcus aureus methicillin-resistance mechanisms

    Directory of Open Access Journals (Sweden)

    Petrović-Jeremić Ljiljana

    2008-01-01

    Full Text Available Background/Aim. In many hospitals in the world and in our country, the spread of methicillin-resistant Staphylococcus aureus (MRSA is so wide that nowdays vancomycin is recommended for empiric treatment of staphylococcal life threatening infections (sepsis, pneumonia instead of beta-lactam antibiotics. The aim of this study was to determine the production of beta-lactamases in hospital and community isolates of staphyloococus aureus, i. e. hospital associated MRSA (HA-MRSA and community associated MRSA (CA-MRSA, the presence of homogeneous and heterogeneous type of methicillin resistance, and border-line resistance in Staphylococcus aureus (BORSA. The aim of this study was also to determine if there was a statistically significant difference between mechanisms of resistance in HA-MRSA and CA-MRSA. Methods. A total 216 clinical Staphylococcus aureus isolates from the General Hospital in the town of Cuprija and 186 ambulance Staphylococcus aureus isolates from the community were examined for the presence of methicillin-resistance using disk-diffusion test with penicillin disk (10 ij, oxacillin disk (1 μg and cefoxitin disk (30 μg. Betalactamases production was detected by nitrocefin disk and betalactamase tablets. Determination of oxacillin minimum inhibitory concentracion (MIC was done by agar-dilution method. Results. The prevalence of HA-MRSA was 57.4%, and CA-MRSA was 17.7% (p < 0.05. There was a higher rate of heterogeneous type of resistance among clinical MRSA isolates (11.1% compared with ambulance ones (3.8% (p < 0.05. The rates of beta-lactamases production were similar among hospital associated isolates (97.5%, as well as in the community associated isolates (95.5% (p > 0.05. There were 4.6 % of BORSA hospital isolates and 3.3 % of BORSA ambulance isolates (p > 0.05. Conclusion. The frequency of MRSA isolates in hospital was significantly higher than in community, as well as the heterogeneous type of resistance. The frequency of BORSA

  18. METABOLITOS AISLADOS DE Zanthoxylum rhoifolium

    Directory of Open Access Journals (Sweden)

    Luis Enrique Cuca Suárez

    2008-04-01

    Full Text Available Una nueva cumarina llamada 3-metoxi-4-(3-metilbut-2-enil-2H-cromen-2-ona fue aislada de la madera de Z. rhoifolium, junto con los compuestos, conocidos dictamnina y N-metilflindersina. Sus estructuras fueron elucidadas por RMN, incluyendo técnicas bidimensionales y por comparación con datos reportados en la literatura.

  19. Methicillin-resistant Staphylococcus aureus: the superbug.

    Science.gov (United States)

    Ippolito, Giuseppe; Leone, Sebastiano; Lauria, Francesco N; Nicastri, Emanuele; Wenzel, Richard P

    2010-10-01

    Over the last decade, methicillin-resistant Staphylococcus aureus (MRSA) strains have emerged as serious pathogens in the nosocomial and community setting. Hospitalization costs associated with MRSA infections are substantially greater than those associated with methicillin-sensitive S. aureus (MSSA) infections, and MRSA has wider economic effects that involve indirect costs to the patient and to society. In addition, there is some evidence suggesting that MRSA infections increase morbidity and the risk of mortality. Glycopeptides are the backbone antibiotics for the treatment of MRSA infections. However, several recent reports have highlighted the limitations of vancomycin, and its role in the management of serious infections is now being reconsidered. Several new antimicrobials demonstrate in vitro activity against MRSA and other Gram-positive bacteria. Data from large surveys indicate that linezolid, daptomycin, and tigecycline are almost universally active against MRSA. This review will briefly discuss the epidemiology, costs, outcome, and therapeutic options for the management of MRSA infections. PMID:20851011

  20. Curcumin Reverse Methicillin Resistance in Staphylococcus aureus

    OpenAIRE

    Su-Hyun Mun; Sung-Bae Kim; Ryong Kong; Jang-Gi Choi; Youn-Chul Kim; Dong-Won Shin; Ok-Hwa Kang; Dong-Yeul Kwon

    2014-01-01

    Curcumin, a natural polyphenolic flavonoid extracted from the rhizome of Curcuma longa L., was shown to possess superior potency to resensitize methicillin-resistant Staphylococcus aureus (MRSA) to antibiotics. Previous studies have shown the synergistic activity of curcumin with β-lactam and quinolone antibiotics. Further, to understand the anti-MRSA mechanism of curcumin, we investigated the potentiated effect of curcumin by its interaction in diverse conditions. The mechanism of anti-MRSA ...

  1. Xanthgranulomatous pyelonephritis associated with Staphylococcus aureus.

    Science.gov (United States)

    Al-Hwiesh, Abdulla K

    2007-11-01

    A 44-year old man with xanthogranulomatous pyelonephritis presented with abdominal distention, left lumber pain, fever, loss of appetite, and loss of weight. He had been known to have diabetes mellitus type II for 20 years, and he was diagnosed to have a left renal stone three months prior to this presentation. The patient's urine and the left psous abscess grew staphylococcus aureus. PMID:17951953

  2. Xanthgranulomatous pyelonephritis associated with staphylococcus aureus

    International Nuclear Information System (INIS)

    A 44-year-old man with xanthgranulomatous pyelonephritis presented with abdominal distention, left lumber pain, fever, loss of appetite and loss of weight. He had been known to have diabetes mellitus type II for 20 years and he was diagnosed to have a left renal stone three months prior to this presentation. The patient's urine and the left psous abscess grew staphylococcus aureus. (author)

  3. Evaluación de la actividad desulfurizadora de aislados nativos de Pseudomonas spp. en presencia de hidrocarburo Desulfurization activity evaluation of native strains of Pseudomonas spp. in the presence of hydrocarbon

    Directory of Open Access Journals (Sweden)

    Alméciga-Díaz Carlos Javier

    2005-07-01

    Full Text Available El principal inconveniente en la combustión de los hidrocarburos es la conversión del azufre y el nitrógeno a sus respectivos óxidos, los cuales participan en la formación de lluvia acida y deterioran el medio ambiente e infraestructuras. La remoción de azufre a partir de compuestos órgano-azufrados mediante el uso de microorganismos ha surgido como una alternativa frente al proceso catalítico de hidrodesulfurización (HDS. En el presente trabajo se evaluó la actividad desulfurizadora de veintitrés aislados nativos de Pseudomonas spp. sobre dibenzotiofeno (DBT, usando un sistema de fermentación con igual proporción de fase acuosa y orgánica (n-hexano en presencia de oleato de etanolamina. Los aislados 02,05 y 06 conservaron su viabilidad en este medio y presentaron una remoción de azufre entre 6,0 y 9,4%, generando los metabolitos DBT-sulfona, DBT-sulfóxido, 2-hidroxibifenilo (2-HBP y sulfato presentes en la ruta metabólica 4S. Con estos aislados se evaluó la actividad desulfurizadora sobre keroseno y se observó una remoción de azufre entre 19,9 y 62,6% y una disminución del poder calorífico entre 0,45 y 5,55%. Palabras clave: dibenzotiofeno, desulfurización, Pseudomonas spp., keroseno.The main difficulty with fossil fuel combustión lies in sulphur and nitrogen becoming converted to their respective oxides, forming part of the acid rain which deteriorates the environment and infrastructure. Removing sulphur from organo-sulfur compounds by using micro-organisms has become an alternative to hydrodesulphurisation (HDS. Twenty-three Pseudomonas spp. native strains' desulphurisation activity on dibenzothiophene (DBT was evaluated by using a fermentation system having equal proportions of aqueous and organic (n-hexane phases in the presence of ethanolamine oléate. The 02, 05 and 06 strains maintained their viability in this médium, presenting 6,0% to 9,4% sulphur removal, producing DBT-sulphone, DBT-sulphoxide, 2

  4. Aspartate inhibits Staphylococcus aureus biofilm formation.

    Science.gov (United States)

    Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

    2015-04-01

    Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp. PMID:25687923

  5. Whole-Genome Sequence of Staphylococcus aureus Strain LCT-SA112

    OpenAIRE

    Wang, Junfeng; Liu, Yanhong; Wan, Daiwei; Fang, Xiangqun; Li, Tianzhi; Guo, Yinghua; Chang, De; Su, Longxiang; Wang, Yajuan; Zhao, Jiao; Liu, Changting

    2012-01-01

    Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. S. aureus is the most common species of Staphylococcus to cause staphylococcal infections, which are very common in clinical medicine. Here we report the genome sequence of S. aureus strain LCT-SA112, which was isolated from S. aureus subsp. aureus CGMCC 1.230.

  6. Efecto de la temperatura sobre películas de un aislado proteico del suero bovino (WPI adsorbidas sobre la interfase aceite-agua

    Directory of Open Access Journals (Sweden)

    Rodríguez Patino, Juan M.

    2002-09-01

    Full Text Available Heat-induced interfacial aggregation of a whey protein isolate (WPI with a high content of β-lactoglobulin, previously adsorbed at the oil-water interface, was studied by interfacial dynamic characteristics (interfacial tension and surface dilational properties performed in a automatic drop tensiometer coupled with microscopic observation and image analysis of the drop after heat-treatment. The temperature, ranging between 20 and 80 ºC, and protein concentration in aqueous bulk phase, ranging between 1.10-1 and 1.10-5% wt/wt, were studied as variables. The pH, and ionic strength were maintained constant at 5 and 0.05 M, respectively. During the heat-treatment, WPI films behave typically as viscoelastic with non-zero phase angle, but with increasing elastic characteristics as the heat-treatment progresses. During isothermal treatment the surface dilational modulus, E, increases and the interfacial tension, σ, and phase angle, φ, decrease with time to a plateau value. The time dependence of E can be quantified by a first-order equation according to two kinetic mechanisms. The rate of thermal changes in WPI adsorbed films increases with protein concentration in solution. Heat-treatment produces irreversible changes in WPI adsorbed films because the interfacial characteristics do not return to original values after cooling back to the initial temperature. Significant changes in interfacial characteristics and drop image associated with interfacial WPI gelation were observed at protein concentration as low as 1.10-5% wt/wt, even for heat-treatment at 40 ºC.En este trabajo se ha estudiado la agregación interfacial inducida por el calor en un aislado proteico del suero bovino (WPI, previamente adsorbido sobre la interfase aceite-agua. Se ha seguido la evolución, durante el tratamiento térmico, de las características dinámicas interfaciales (tensión interfacial y propiedades dilatacionales superficiales, determinadas en un tensi

  7. Caracterización molecular y agronómica de aislados de Trichoderma spp nativos del noreste de México

    Directory of Open Access Journals (Sweden)

    José Luis Hernández Mendoza

    2012-06-01

    Full Text Available Normal 0 21 false false false ES-CO X-NONE X-NONE MicrosoftInternetExplorer4 Título en ingles: Molecular and agronomic characterization of Trichoderma spp natives of northeastern Mexico  Resumen Trichoderma sp es un hongo frecuentemente usado en actividades agrícolas, pues actúa como antagonista de diversas especies de hongos fitopatógenos. En este estudio se realizó el aislamiento de cuatro cepas de Trichoderma sp nativas del noreste de México, las cuales fueron identificadas a nivel molecular mediante la secuenciación del ITS 1. Además se evaluó su capacidad antagonista en contra los hongos fitopatógenos Macrophomina phaseolina y Fusarium oxysporum, que afectan severamente cultivos de sorgo, maíz y fríjol en el noreste de México. La identificación se realizó de acuerdo al grado de concordancia con secuencias reportadas y corresponden a las especies T. hammatum (HK701;  T. koningiopsis (HK702; T. asperellum (HK703 y Trichoderma sp (HK704. Por otra parte, las pruebas de antagonismo muestran que los aislados HK701, HK703 y HK704 inhiben por competencia el crecimiento de M. phaseolina y F. oxysporum, mientras que HK702 tiene la capacidad para hiperparasitar dichos fitopatógenos. Finalmente, se evaluó la promoción de crecimiento de T. asperellum HK703, en maíz (Pionner 30P49®, usando para ello concentraciones de tratamiento de 1x10e2 hasta 1x10e6 esp/mL. En estos ensayos se midió la producción de biomasa. Los resultados muestran que en concentraciones intermedias se tiene el mayor incremento en altura de plantas y mayor producción de peso seco en follaje y raíz. Entre los parámetros antes mencionados existen diferencias significativas. Palabras clave: control biológico, antagonismo, biofertilizantes, Zea maiz, Sorghum bicolor. Abstract Trichoderma sp is a fungus often used in agricultural activities, because it acts as an antagonist of several species of plant pathogenic fungi. In this study four strains of Trichoderma

  8. Liberación de endotelina-1 por angiotensina ll en miocitos cardíacos aislados Angiotensin II-induced endothelin-1 release in cardiac myocytes

    Directory of Open Access Journals (Sweden)

    María C. Villa-Abrille

    2006-06-01

    Full Text Available Muchos de los efectos de la angiotensina II (Ang II son mediados en realidad por la acción de endotelina (ET endógena liberada y/o producida en respuesta a la Ang II. En este trabajo evaluamos la interacción Ang II/ET-1, sus consecuencias en la contractilidad cardíaca y el papel de las especies reactivas del oxígeno (EROs. Se usaron cardiomiocitos aislados de gato. La Ang II, 1 nM, produjo un efecto inotrópico positivo (EIP de 31.8±3.8% que fue cancelado por inhibición de los receptores AT1, de los receptores de ET, del intercambiador Na+/H+ (NHE, del modo inverso del intercambiador Na+/Ca2+ (NCX o por el secuestro de EROs. La Ang II, 100 nM, produjo un EIP de 70.5±7.6% que fue cancelado por inhibición de los receptores AT1 y bloqueado en parte por inhibición de los receptores de ET, del NHE, del modo inverso del NCX o por el secuestro de EROs. La Ang II, 1 nM, incrementó el ARNm de la preproET-1 lo cual fue anulado por el bloqueo de los receptores AT1. Los resultados permiten concluir que el EIP de la Ang II es debido a la acción de la ET-1 endógena liberada/formada por la Ang II. La ET-1 produce: estimulación del NHE, activación del modo inverso del NCX y un consecuente EIP. Dentro de esta cascada también participarían los EROs.Many of the effects thought to be due to angiotensin II (Ang II are due to the release/formation of endothelin (ET. We tested whether Ang II elicits its positive inotropic effect (PIE by the action of endogenous ET-1 and the role played by the reactive oxygen species (ROS in this mechanism. Experiments were performed in cat isolated ventricular myocytes in which sarcomere shortening (SS was measured to asses contractility after pharmacological interventions and the effect of Ang II on inotropism were analyzed. Ang II 1 nM increased SS by 31.8±3.8% (p<0.05. This PIE was cancelled by AT1 receptor blockade, by ET-1 receptors blockade, by Na+/H+ exchanger (NHE inhibition, by reverse mode Na+/Ca2

  9. [Raw milk-associated Staphylococcus aureus intoxication in children].

    Science.gov (United States)

    Giezendanner, N; Meyer, B; Gort, M; Müller, P; Zweifel, C

    2009-07-01

    Four hours after the consumption of raw goat milk, three Swiss children came down with emesis and diarrhea in July 2008. First investigations showed that the milk originated from a goat suffering from clinical mastitis (Staphylococcus aureus). In the milk sample from the untreated left udder, Staphylococcus aureus counts reached 5.0 x 10(7) CFU ml(-1). By PCR, the gene for the staphylococcal enterotoxin D was found in isolated strains. The consumption of raw milk is rarely associated with Staphylococcus aureus intoxications. Due to the flora naturally present in raw milk, Staphylococcus aureus normally cannot multiply sufficiently. However, in the present case, high Staphylococcus aureus counts were already present in the milk due to the mastitis of the goat. This amount sufficed to cause a Staphylococcus aureus intoxication in the children. PMID:19565455

  10. Antibody responses in patients with invasive Staphylococcus aureus infections

    OpenAIRE

    Jacobsson, G; Colque-Navarro, P.; Gustafsson, E.; Andersson, R.; Möllby, R

    2010-01-01

    Abstract Correlation between antibody response and clinical outcome in Staphylococcus aureus bacteremia has yielded conflicting results. Immunization schedules have failed in clinical trials. Is the humoral response toward S. aureus of protective nature? A prospective study was performed in patients with invasive S. aureus (ISA) infections during the period 2003?2005. The antibody levels were determined at the beginning and at the end of treatment and one month later (n?=?96, n?=?7...

  11. Vitamin D sufficiency and Staphylococcus aureus infection in children.

    Science.gov (United States)

    Wang, Jeffrey W; Hogan, Patrick G; Hunstad, David A; Fritz, Stephanie A

    2015-05-01

    Vitamin D promotes epithelial immunity by upregulating antimicrobial peptides, including LL-37, which have bactericidal activity against Staphylococcus aureus. We found that children with vitamin D deficiency or insufficiency [25-hydroxyvitamin D recurrent, rather than primary, S. aureus skin or soft tissue infection. Vitamin D sufficiency may be one of a myriad of host and environmental factors that can be directly impacted to reduce the frequency of S. aureus skin and soft tissue infection. PMID:25860535

  12. Mapping the Distribution of Invasive Staphylococcus aureus across Europe

    OpenAIRE

    Grundmann, Hajo; Aanensen, David M.; van den Wijngaard, Cees C.; Brian G Spratt; Harmsen, Dag; Friedrich, Alexander W.; ,

    2010-01-01

    Editors' Summary Background The bacterium Staphylococcus aureus lives on the skin and in the nose of about a third of healthy people. Although S. aureus usually coexists peacefully with its human carriers, it is also an important disease-causing organism or pathogen. If it enters the body through a cut or during a surgical procedure, S. aureus can cause minor infections such as pimples and boils or more serious, life-threatening infections such as blood poisoning and pneumonia. Minor S. aureu...

  13. Infection control of Staphylococcus aureus : spa typing to elucidate transmission

    OpenAIRE

    Mernelius, Sara

    2015-01-01

    Staphylococcus aureus is a commensal of the human flora, primarily colonizing the anterior nares and throat, but it may also cause infections ranging from mild skin and soft tissue infections to severe diseases such as endocarditis and septicemia. S. aureus is also a major nosocomial problem increasing with the worldwide dissemination of methicillin-resistant S. aureus (MRSA). The main vector for bacterial cross-transmission in healthcare settings is the hands of healthcare workers (HCWs). No...

  14. Staphylococcus aureus atsparumas antibiotikams ir fagotipų paplitimas

    OpenAIRE

    Kareivienė, Violeta; Pavilonis, Alvydas; Sinkutė, Gintarė; Liegiūtė, Sigutė; Gailienė, Greta

    2006-01-01

    Objective. The aim of this study was to identify the phage groups of Staphylococcus aureus strains, their prevalence, and resistance of different phage groups to antibiotics. Materials and methods. A total of 294 Staphylococcus aureus strains in Kaunas hospitals were obtained; they were phage typed and their resistance to antibiotics was determined. We used the method of routine dilution to test 17 antibiotics against the isolates. Susceptibility of Staphylococcus aureus to studied antibio...

  15. Threat of drug resistant Staphylococcus aureus to health in Nepal

    OpenAIRE

    Ansari, Shamshul; Nepal, Hari Prasad; Gautam, Rajendra; Rayamajhi, Nabin; Shrestha, Sony; Upadhyay, Goma; Acharya, Anju; Chapagain, Moti Lal

    2014-01-01

    Background Staphylococcus aureus is the most commonly isolated organism from the different clinical samples in hospital. The emergence and dissemination of methicillin resistant Staphylococcus aureus (MRSA) and growing resistance to non-beta-lactam antibiotics is making treatment of infections due to this organism increasingly difficult. Methods This study was conducted to determine the frequency of Staphylococcus aureus isolated from different clinical samples, rates of MRSA and full antibio...

  16. Epicutaneous Model of Community-Acquired Staphylococcus aureus Skin Infections

    OpenAIRE

    Prabhakara, Ranjani; Foreman, Oded; De Pascalis, Roberto; Lee, Gloria M.; Plaut, Roger D.; Kim, Stanley Y.; Stibitz, Scott; Elkins, Karen L.; Merkel, Tod J.

    2013-01-01

    Staphylococcus aureus is one of the most common etiological agents of community-acquired skin and soft tissue infection (SSTI). Although the majority of S. aureus community-acquired SSTIs are uncomplicated and self-clearing in nature, some percentage of these cases progress into life-threatening invasive infections. Current animal models of S. aureus SSTI suffer from two drawbacks: these models are a better representation of hospital-acquired SSTI than community-acquired SSTI, and they involv...

  17. ELABORACIÓN Y CARACTERIZACIÓN DE PELíCULAS DE GLICOPROTEÍNAS OBTENIDAS MEDIANTE REACCIÓN DE MAILLARD UTILIZANDO ALMIDÓN ACETILADO y AISLADO PROTEICO DE SUERO LÁCTEO

    OpenAIRE

    P.B. Zamudio-Flores; L.A. Bello-Pérez

    2013-01-01

    Se realizó una acetilación del almidón de avena a dos diferentes niveles (bajo y medio), y se caracterizaron mediante análisis químico proximal, difracción de rayos X y microscopia electrónica de barrido. Los almidones acetilados se sometieron a una reacción de Maillard con aislado proteico de suero lácteo, obteniéndose glicoproteínas con diferente grado de glicosilación (alto, medio y bajo), las cuales se caracterizaron por el método espectrofotométrico del O-ftaldialdebído (OPA). Con las gl...

  18. Efectos de la substitución de conexina 43 por conexina 32 en la tolerancia a la isquemia y en la protección por precondicionamiento en corazones aislados de ratón

    OpenAIRE

    Sánchez García, José Antonio; Rodríguez Sinovas, Antonio; García-Dorado García, Diego

    2011-01-01

    La conexina 43 es una proteína que juega un papel importante en la fisiopatología de la isquemia - reperfusión y en la señalización de la protección cardíaca. Para investigar si este papel está relacionado con las propiedades específicas de esta isoforma, se utilizó un modelo de corazón aislado de ratones transgénicos knock-in, en los que la conexina 43 se reemplazó por conexina 32. Los resultados de este trabajo demuestran un efecto modulador de la conexina 43 en el metabolismo energético, e...

  19. VISA/VRSA (Vancomycin-Intermediate/Resistant Staphylococcus aureus) in Healthcare Settings

    Science.gov (United States)

    ... to vancomycin and other antimicrobial agents. What is Staphylococcus aureus? Staphylococcus aureus is a bacterium commonly found on the ... control personnel. Investigation and Control of Vancomycin-Resistant Staphylococcus aureus (VRSA) [PDF - 300 KB] - This document is ...

  20. Staphylococcus aureus: resistance pattern and risk factors

    Directory of Open Access Journals (Sweden)

    Mohammad Naghavi-Behzad

    2015-03-01

    Full Text Available Introduction: Methicillin resistant Staphylococcus aureus (MRSA has emerged as a nosocomial pathogen of major worldwide importance and is an increasingly frequent cause of community-acquired infections. In this study, different risk factors and MRSA resistance pattern were investigated. Methods: In a 24 months period, all of the patients who were confined to bed in the surgery ward were included in the study. Then they were assessed to find out as if they had MRSA infection when hospitalized and once when they were discharged. Almost 48 h after admission, when patients were discharged, social and medical histories were acquired. Acquired samples were examined. Results: During the present study of 475 patients, 108 patients (22.8% had S. aureus. About frequency of antibiotic resistance among collected S. aureus colonies, erythromycin resistance, was the most frequent antibiotic resistance, also resistance to vancomycin was 0.4% that was the least. Only hospitalization duration had statistically significant correlation with antibiotic resistance, also resistance to erythromycin had statistically significant relation with history of surgery and alcohol consumption. Of all 34 MRSA species, 22 (64.7% samples were resistant to erythromycin, 17 (50.0% resistant to cefoxitin, 5 (14.7% resistant to mupirocin, 1 (2.9% resistant to vancomycin and 1 (2.9% resistant to linezolid. Conclusion: The results of the current study show that among hospitalized patients, there is resistance against methicillin. Since based on results of the study there is resistance against oxacillin and erythromycin in most cases, administering appropriate antibiotics have an important role in minimizing the resistance burden among bacterial species.

  1. Staphylococcus aureus bacteriuria as a prognosticator for outcome of Staphylococcus aureus bacteremia: a case-control study

    Directory of Open Access Journals (Sweden)

    Weinstein Robert A

    2010-07-01

    Full Text Available Abstract Background When Staphylococcus aureus is isolated in urine, it is thought to usually represent hematogenous spread. Because such spread might have special clinical significance, we evaluated predictors and outcomes of S. aureus bacteriuria among patients with S. aureus bacteremia. Methods A case-control study was performed at John H. Stroger Jr. Hospital of Cook County among adult inpatients during January 2002-December 2006. Cases and controls had positive and negative urine cultures, respectively, for S. aureus, within 72 hours of positive blood culture for S. aureus. Controls were sampled randomly in a 1:4 ratio. Univariate and multivariable logistic regression analyses were done. Results Overall, 59% of patients were African-American, 12% died, 56% of infections had community-onset infections, and 58% were infected with methicillin-susceptible S. aureus (MSSA. Among 61 cases and 247 controls, predictors of S. aureus bacteriuria on multivariate analysis were urological surgery (OR = 3.4, p = 0.06 and genitourinary infection (OR = 9.2, p = 0.002. Among patients who died, there were significantly more patients with bacteriuria than among patients who survived (39% vs. 17%; p = 0.002. In multiple Cox regression analysis, death risks in bacteremic patients were bacteriuria (hazard ratio 2.9, CI 1.4-5.9, p = 0.004, bladder catheter use (2.0, 1.0-4.0, p = 0.06, and Charlson score (1.1, 1.1-1.3, p = 0.02. Neither length of stay nor methicillin-resistant Staphylococcus aureus (MRSA infection was a predictor of S. aureus bacteriuria or death. Conclusions Among patients with S. aureus bacteremia, those with S. aureus bacteriuria had 3-fold higher mortality than those without bacteriuria, even after adjustment for comorbidities. Bacteriuria may identify patients with more severe bacteremia, who are at risk of worse outcomes.

  2. Intracellular proliferation of S. aureus in osteoblasts and effects of rifampicin and gentamicin on S. aureus intracellular proliferation and survival

    Directory of Open Access Journals (Sweden)

    W Mohamed

    2014-10-01

    Full Text Available Staphylococcus aureus is the most clinically relevant pathogen regarding implant-associated bone infection and its capability to invade osteoblasts is well known. The aim of this study was to investigate firstly whether S. aureus is not only able to invade but also to proliferate within osteoblasts, secondly to delineate the mechanism of invasion and thirdly to clarify whether rifampicin or gentamicin can inhibit intracellular proliferation and survival of S. aureus. The SAOS-2 osteoblast-like cell line and human primary osteoblasts were infected with S. aureus EDCC5055 and S. aureus Rosenbach 1884. Both S. aureus strains were able to invade efficiently and to proliferate within human osteoblasts. Immunofluorescence microscopy showed intracellular invasion of S. aureus and transmission electron microscopy images could demonstrate bacterial division as a sign of intracellular proliferation as well as cytosolic bacterial persistence. Cytochalasin D, the major actin depolymerisation agent, was able to significantly reduce S. aureus invasion, suggesting that invasion was enabled by promoting actin rearrangement at the cell surface. 7.5 μg/mL of rifampicin was able to inhibit bacterial survival in SAOS-2 cells with almost complete elimination of bacteria after 4 h. Gentamicin could also kill intracellular S. aureus in a dose-dependent manner, an effect that was significantly lower than that observed using rifampicin. In conclusion, S. aureus is not only able to invade but also to proliferate in osteoblasts. Invasion seems to be associated with actin rearrangement at the cell surface. Rifampicin is effective in intracellular eradication of S. aureus whereas gentamicin only poorly eliminates intracellularly replicating bacteria.

  3. Duplex Identification of Staphylococcus aureus by Aptamer and Gold Nanoparticles.

    Science.gov (United States)

    Chang, Tianjun; Wang, Libo; Zhao, Kexu; Ge, Yu; He, Meng; Li, Gang

    2016-06-01

    Staphylococcus aureus is the top common pathogen causing infections and food poisoning. Identification of S. aureus is crucial for the disease diagnosis and regulation of food hygiene. Herein, we report an aptamer-AuNPs based method for duplex identification of S. aureus. Using AuNPs as an indicator, SA23, an aptamer against S. aureus, can well identify its target from Escherichia coli, Listeria monocytogenes and Pseudomonas aeruginosa. Furthermore, we find citrate-coated AuNPs can strongly bind to S. aureus, but not bind to Salmonella enterica and Proteus mirabilis, which leads to different color changes in salt solution. This colorimetric response is capable of distinguishing S. aureus from S. enteritidis and P. mirabilis. Thus, using the aptasensor and AuNPs together, S. aureus can be accurately identified from the common pathogens. This duplex identification system is a promising platform for simple visual identification of S. aureus. Additionally, in the aptasensing process, bacteria are incubated with aptamers and then be removed before the aptamers adding to AuNPs, which may avoid the interactions between bacteria and AuNPs. This strategy can be potentially applied in principle to detect other cells by AuNPs-based aptasensors. PMID:27427591

  4. Lysostaphin in treatment of neonatal Staphylococcus aureus infection.

    Science.gov (United States)

    Oluola, Okunola; Kong, Lingkun; Fein, Mindy; Weisman, Leonard E

    2007-06-01

    This study describes lysostaphin's effect against methicillin-sensitive Staphylococcus aureus in suckling rats. Standard techniques determined minimal inhibitory and bactericidal concentrations, pharmacokinetics, and efficacy. The numbers of surviving rats after vancomycin, oxacillin, and lysostaphin treatment were comparable and were different from that of controls (P < 0.00001). Lysostaphin appears effective in the treatment of neonatal S. aureus infection. PMID:17420212

  5. Susceptibility of methicillin-resistant Staphylococcus aureus to lysostaphin.

    OpenAIRE

    Huber, M M; Huber, T. W.

    1989-01-01

    One hundred and eleven isolates of methicillin-resistant Staphylococcus aureus recovered from patients at the Olin E. Teague Veterans Center from March 1983 to April 1987 were as susceptible to lysis by lysostaphin as methicillin-susceptible S. aureus controls were.

  6. Mechanism of resistance to some cephalosporins in Staphylococcus aureus.

    OpenAIRE

    Kono, M; Sasatsu, M; O'Hara, K; Shiomi, Y.; HAYASAKA, T.

    1983-01-01

    The mechanism of resistance to some cephalosporins in Staphylococcus aureus strains was investigated with high-pressure liquid chromatography and nuclear magnetic resonance spectrometry. Drug inactivation by penicillinase was found to be the main mechanism of resistance to cefazolin, cephaloridine, and cephalothin in S. aureus.

  7. Activity of and Resistance to Moxifloxacin in Staphylococcus aureus

    OpenAIRE

    Ince, Dilek; Zhang, Xiamei; Hooper, David C.

    2003-01-01

    Moxifloxacin has enhanced potency against Staphylococcus aureus, lower propensity to select for resistant mutants, and higher bactericidal activity against highly resistant strains than ciprofloxacin. Despite similar activity against purified S. aureus topoisomerase IV and DNA gyrase, it selects for topoisomerase IV mutants, making topoisomerase IV the preferred target in vivo.

  8. Changing Trends in Resistance Pattern of Methicillin Resistant Staphylococcus aureus

    OpenAIRE

    Kali, Arunava; Stephen, Selvaraj; Umadevi, Sivaraman; Kumar, Shailesh; Joseph, Noyal Mariya; Srirangaraj, Sreenivasan

    2013-01-01

    Background: Methicillin resistance in Staphylococcus aureus is associated with multidrug resistance, an aggressive course, increased mortality and morbidity in both community and health care facilities. Monitoring of newly emerging and prevalent Methicillin Resistant Staphylococcus aureus (MRSA) strains for their resistance patterns to conventional as well as novel drugs, are essential for infection control.

  9. Effect of Mupirocin on Nasal Carriage of Staphylococcus Aureus

    NARCIS (Netherlands)

    M. Bulanda; M. Gruszka; B. Heczko

    1989-01-01

    textabstractMupirocin eliminates nasal carriage of staphylococcal aureus among medical and surgical personnel for periode varying from several weeks upto one year. In persons recolonized after therapy densites of S. aureus population in nares were much lower than in the same persons before therapy.

  10. Cirugía de reemplazo valvular aórtico aislado en pacientes octogenarios: evaluación, riesgo operatorio y resultados a mediano plazo

    Directory of Open Access Journals (Sweden)

    Fernando Piccinini

    2010-01-01

    Full Text Available RESUMENIntroducciónLas indicaciones y los beneficios del reemplazo valvular aórtico han sido claramente establecidos, aun para poblaciones añosas, de aumentada comorbilidad. Aun así, la manipulación de ateromas aórticos, el uso de circulación extracorpórea y de clampeo aórtico, el paro cardíaco y la descalcificación ligadas a esta técnica y sus eventuales consecuencias generan dudas acerca de su indicación en este grupo de pacientes.ObjetivosComunicar la morbimortalidad del procedimiento en octogenarios y validar la utilidad de los puntajes de predicción de riesgo utilizados más frecuentemente.Material y métodosSe estudiaron 87 pacientes octogenarios sometidos a reemplazo aórtico aislado; se analizaron variables preoperatorias, intraoperatorias y posoperatorias y se aplicó el Euroscore; para facilitar el subanálisis del Euroscore logístico, la población se dividió en tres grupos: riesgo bajo, moderado y alto. Se utilizó técnica quirúrgica convencional. Para el seguimiento, se analizó la historia clínica y/o se realizó encuesta telefónica.ResultadosLa mediana de edad fue de 83 ± 2,5 años, con un rango de 80 a 89 años. El 60% de la población en estudio era de sexo femenino. La indicación quirúrgica fue estenosis 92%, endocarditis activa 4,6% y enfermedad valvular 3,4%. Antecedentes: hipertensión 71%, tabaquismo 31%, dislipidemia 39%, diabetes 11,5%, EPOC 10%, IRC-diálisis 2,3%, ACV 11,5%, IAM previo 8%, fibrilación auricular 16%, reoperación 15%. Cuadro clínico: asintomático 3,45%, angina crónica estable 10,3%, angina inestable 11%, ICC 13,8%, disnea CF III-IV 60%. Disfunción ventricular izquierda moderada-grave 18,3%. Riesgo por Euroscore logístico 12,4% ± 15%. El tiempo operatorio promedio fue de 200 ± 61,7 min, el de CEC de 86 ± 32,5 min y el de clampeo aórtico de 65 ± 18,2 min. Complicaciones: sangrado médico 17,2%, reoperación sangrado 5,7%, bajo gasto cardíaco 13,8%, inotrópicos > 48 horas

  11. Vasodilator profile of flavonoid and phenylbutanoid compounds isolated from Croton schiedeanus Schlecht PERFIL VASODILATADOR DE COMPUESTOS FLAVONOIDES Y FENILBUTANOIDES AISLADOS DE CROTON SCHIEDEANUS SCHLECHT

    Directory of Open Access Journals (Sweden)

    Sofía Ximena Correa-Hernández

    2008-12-01

    para el tratamiento de la hipertensión arterial. Objetivo. Evaluar el efecto vasodilatador de los flavonoides: 3-O-metilquercetina, 3,7-di-O-metilquercetina, y 3,3',4',7-tetra-O-metilquercetina; y los fenilbutanoides: (2S-7,9-dime--to--xiro---doden-drol, (2S-2-acetato de 7,9-dime-toxirododendrol y (2S- 2,8-diacetato de 7,9-dimetoxirodo-dendrol en anillos de aorta de ratas Wistar. Material y métodos. Estos compuestos se evaluaron en anillos de aorta precontraídos con fenilefrina (1 µM o KCl (80 mM. Para examinar posibles interacciones con endotelio, óxido nítrico, guanilato ciclasa, prostanoides o canales de K+ATP, aquéllos con mayores efectos vasodilatadores: 3-O-metilquercetina y 3,7-di-O-metilquercetina, se evaluaron en anillos estimulados con fenilefrina en presencia o ausencia de: endotelio, L-NAME (G -nitro-L-Arginina-Metil Ester, 100 µM, ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-ona, 1 µM, meclofenamato sódico (10 µM o glibenclamida (1 µM. Resultados. En contraste con los compuestos fenilbutanoides que no arrojaron actividad relajante significativa, 3-O-metilquercetina y 3,7-di-O-metilquercetina mostraron una respuesta importante con concentraciones inhibitorias 50 (CI50 de 2,5 y 4,9 µM respectivamente frente a fenilefrina. ODQ y L-NAME desplazaron efectivamente a la derecha la curva dosis-respuesta, en particular la 3-O-metilquercetina (razón de IC50: 7,4 y 3,8. Conclusión. 3-O-metilquercetina y 3,7-di-O-metilquer-cetina, flavonoides aislados de Croton schiedeanus, ejercen importantes efectos vasodilatadores vinculados con la vía de NO/GMPc. Estos resultados soportan al uso etnobotánico de esta especie.

  12. A porcine model of haematogenous brain infectionwith staphylococcus aureus

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Agerholm, Jørgen Steen; Nielsen, Ole Lerberg;

    2012-01-01

    A PORCINE MODEL OF HAEMATOGENOUS BRAIN INFECTION WITH STAPHYLOCOCCUS AUREUS Astrup Lærke1, Agerholm Jørgen1, Nielsen Ole1, Jensen Henrik1, Leifsson Páll1, Iburg Tine2. 1: Faculty of Health and Medical Sciences, University of Copenhagen, Denmark boye@life.ku.dk 2: National Veterinary Institute......, Uppsala, Sweden Introduction Staphylococcus aureus (S.aureus) is a common cause of sepsis and brain abscesses in man and a frequent cause of porcine pyaemia. Here we present a porcine model of haematogenous S. aureus-induced brain infection. Materials and Methods Four pigs had two intravenous catheters...... inserted surgically, one in a. carotis communis and one in v. jugularis externa. All pigs received 106 CFU/kg body weight S. aureus through the arterial catheter. Bacteria were either suspended in isotonic saline infused at constant flow for 60 minutes (two pigs) or given as a bolus injection of autologoue...

  13. Antimicrobial drug resistance ofStaphylococcus aureus in dairy products

    Institute of Scientific and Technical Information of China (English)

    Sasidharan S; Prema B; Yoga Latha L

    2011-01-01

    Objective:To evaluate the prevalence of multidrug resistantStaphylococcus aureus(S. aureus) in dairy products.Methods:Isolation and identification ofS. aureus were performed in3 dairy-based food products. The isolates were tested for their susceptibility to5 different common antimicrobial drugs.Results:Of50 samples examined,5 (10%) were contaminated with S. aureus. Subsequently, the5 isolates were subjected to antimicrobial resistance pattern using five antibiotic discs (methicillin, vancomycin, kanamycin, chloramphenicol and tetracycline). Sample 29 showed resistance to methicillin and vancomycin. Sample18 showed intermediate response to tetracycline. The other samples were susceptible to all the antibiotics tested.Conclusions:The results provide preliminary data on sources of food contamination which may act as vehicles for the transmission of antimicrobial-resistantStaphylococcus.Therefore, it enables us to develop preventive strategies to avoid the emergence of new strains of resistantS. aureus.

  14. Characterization of methicillin-resistant Staphylococcus aureus Sequence Type 398

    DEFF Research Database (Denmark)

    Christiansen, Mette Theilgaard

    Staphylococcus aureus is an opportunistic pathogen that colonizes the nares and skin surfaces of several animal species, including man. S. aureus can cause a wide variety of infections ranging from superficial soft tissue and skin infections to severe and deadly systemic infections. Traditionally S...... for LA-MRSA ST398 survival on porcine skin and nasal epithelium ex vivo were identified. These genes could represent targets for de-colonization, which could help prevent further spread and adaption of LA-MRSA ST398. Manuscript III describes the construction of the S. aureus VirulenceFinder database....... The database can be applied for identification of virulence genes in S. aureus using whole genome 5 sequence data. The S. aureus VirulenceFinder will be part of the tool package generated for the Centre for Genomic Epidemiology (CGE) (www.genomicepidemiology.org)....

  15. Where does a Staphylococcus aureus vaccine stand?

    Science.gov (United States)

    Fowler, V G; Proctor, R A

    2014-05-01

    In this review, we examine the current status of Staphylococcus aureus vaccine development and the prospects for future vaccines. Examination of the clinical trials to date show that murine models have not predicted success in humans for active or passive immunization. A key factor in the failure to develop a vaccine to prevent S. aureus infections comes from our relatively limited knowledge of human protective immunity. More recent reports on the elements of the human immune response to staphylococci are analysed. In addition, there is some controversy concerning the role of antibodies for protecting humans, and these data are reviewed. From a review of the current state of understanding of staphylococcal immunity, a working model is proposed. Some new work has provided some initial candidate biomarker(s) to predict outcomes of invasive infections and to predict the efficacy of antibiotic therapy in humans. We conclude by looking to the future through the perspective of lessons gleaned from the clinical vaccine trials. PMID:24476315

  16. Efektivitas Ekstrak Daun Jambu Biji Buah Putih Terhadap Pertumbuhan Staphylococcus aureus Dari Abses Dan Staphylococcus aureus (ATCC® 29213™)

    OpenAIRE

    Sinurat, Jojor

    2016-01-01

    Daun jambu biji mengandung senyawa aktif seperti tanin, triterpenoid, flavonoid, saponin yang mempunyai efek antibakteri. Mekanisme tanin sebagai antibakteri dengan mengkerutkan dinding sel dan membran sel, inaktivasi enzim, inaktivasi fungsi materi genetik bakteri. Flavonoid merusak sel bakteri, denaturasi protein, inaktivasi enzim dan menyebabkan lisis. Triterpenoid dan saponin menghambat pertumbuhan Staphylococcus aureus dengan cara merusak struktur membran sel. Staphylococcus aureus adala...

  17. The molecular changing mechanism of Ampicillin-Sulbactam resistant Staphylococcus aureus towards Methicillin resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Mieke Hemiawati Satari

    2005-12-01

    Full Text Available The aim of this study was to determine the molecular changing of S.aureus, which is resistant to Ampicillin-Sulbactam and then become resistant to Methicillin as a result of improper dosage. The study was conducted by isolating Ampicillin-Sulbactam resistant and Methicillin Resistant S.aureus (MRSA, afterwards an amplification process was performed by PCR (Polymerase Chain Reaction. to isolate the betalactamase enzyme regulator and PBP 2a genes. The result of this research showed that there were a deletion of few amino acids from the regulator gene, and a suspicion that the DNA sequence had been substituted from PBP 2 gene into PBP 2a (gen mec. This process had formed MRSA.

  18. Indole and 7-benzyloxyindole attenuate the virulence of Staphylococcus aureus.

    Science.gov (United States)

    Lee, Jin-Hyung; Cho, Hyun Seob; Kim, Younghoon; Kim, Jung-Ae; Banskota, Suhrid; Cho, Moo Hwan; Lee, Jintae

    2013-05-01

    Human pathogens can readily develop drug resistance due to the long-term use of antibiotics that mostly inhibit bacterial growth. Unlike antibiotics, antivirulence compounds diminish bacterial virulence without affecting cell viability and thus, may not lead to drug resistance. Staphylococcus aureus is a major agent of nosocomial infections and produces diverse virulence factors, such as the yellow carotenoid staphyloxanthin, which promotes resistance to reactive oxygen species (ROS) and the host immune system. To identify novel antivirulence compounds, bacterial signal indole present in animal gut and diverse indole derivatives were investigated with respect to reducing staphyloxanthin production and the hemolytic activity of S. aureus. Treatment with indole or its derivative 7-benzyloxyindole (7BOI) caused S. aureus to become colorless and inhibited its hemolytic ability without affecting bacterial growth. As a result, S. aureus was more easily killed by hydrogen peroxide (H₂O₂) and by human whole blood in the presence of indole or 7BOI. In addition, 7BOI attenuated S. aureus virulence in an in vivo model of nematode Caenorhabditis elegans, which is readily infected and killed by S. aureus. Transcriptional analyses showed that both indole and 7BOI repressed the expressions of several virulence genes such as α-hemolysin gene hla, enterotoxin seb, and the protease genes splA and sspA and modulated the expressions of the important regulatory genes agrA and sarA. These findings show that indole derivatives are potential candidates for use in antivirulence strategies against persistent S. aureus infection. PMID:23318836

  19. The changing epidemiology of Staphylococcus aureus bloodstream infection

    DEFF Research Database (Denmark)

    Galbraith, J.C.; Valiquette, G.; Kennedy, K.J.;

    2013-01-01

    Clin Microbiol Infect ABSTRACT: Although the epidemiology of Staphylococcus aureus bloodstream infection (BSI) has been changing, international comparisons are lacking. We sought to determine the incidence of S. aureus BSI and assess trends over time and by region. Population-based surveillance...... episodes of S. aureus BSI were identified. The overall annual incidence rate for S. aureus BSI was 26.1 per 100 000 population, and those for methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) were 24.2 and 1.9 per 100 000, respectively. Although the overall incidence...... of community-onset MSSA BSI (15.0 per 100 000) was relatively similar across regions, the incidence rates of hospital-onset MSSA (9.2 per 100 000), community-onset MRSA (1.0 per 100 000) and hospital-onset MRSA (0.8 per 100 000) BSI varied substantially. Whereas the overall incidence of S. aureus BSI did...

  20. Evaluación in vitro de la actividad inhibitoria de extractos vegetales sobre aislados de Colletotrichum spp In vitro evaluation of inhibitory activity of plant extracts on Colletotrichum spp

    Directory of Open Access Journals (Sweden)

    Alexander Pérez Cordero

    2011-04-01

    Full Text Available Se evaluó la actividad inhibitoria in vitro de extractos de hojas de Melissa officinalis, Origanum vulgare, Jatropha gossypilia, Eucalyptus sp., Melia azederach y Mascagnia concinna sobre aislados de hongo del género Colletotrichum, causante de la enfermedad antracnosis en el cultivo del ñame (Dioscorea alata, D. rotundata en el departamento de Sucre, Colombia. Para la obtención de extractos etanólicos de hojas de M. officinalis y O. vulgare, se utilizó el método de percolación y para las otras especies vegetales, el método de Soxhlet. Una vez preparados los extractos de hojas, se evaluó su actividad inhibitoria sobre seis aislados de hongo del género Colletotrichum (BVC 279a, BVC 279b, BVC 853, BVC 040, BVC 342 y BVC 507. Para la prueba inhibitoria se utilizó el método de siembra directa sobre la superficie del medio papa-dextrosa-agar. Sobre las diferentes cepas se adicionaron 250 µl de cada extracto por separado. Se utilizó un control positivo con nistatina (4 mg/ml y un testigo absoluto sin ningún tipo de tratamiento. La prueba se evaluó midiendo el crecimiento radial de cada cepa con los diferentes tratamientos a 96 y 168 h. Se utilizó un diseño de bloques completamente al azar con tres repeticiones, para probar diferencias significativas entre tratamientos, cepas (aislados y tiempo de inhibición. Los resultados expresados en porcentaje de inhibición, mostraron una alta actividad de los extractos obtenidos de las hojas de las plantas de M. azederach y M. concinna, sobre los hongos evaluados y su acción fue similar al control positivo.The objective of this study was to evaluate in vitro inhibitory activity of extracts from leaves of Melissa officinalis, Origanum vulgare, Jatropha gossypilia, Eucalyptus sp. Melia azederach and Mascagnia concinna on isolated fungus of the genus Colletotrichum, which causes anthracnose disease in the crop of yam (Dioscorea alata, D. rotundata in the department of Sucre, Colombia. To obtain

  1. Staphylococcus aureus: portadores entre manipuladores de alimentos Staphylococcus aureus: food handler carriers

    Directory of Open Access Journals (Sweden)

    Maria Stella Gonçalves Raddi

    1988-02-01

    Full Text Available Foram colhidas amostras de mãos e fossas nasais de 48 manipuladores de alimentos das principais casas comerciais da cidade de Araraquara, Estado de São Paulo (Brasil, e de 20 estudantes universitários. Dentre os indivíduos foram encontrados 44,1% e 34,8% que portavam Staphylococcus aureus em fossas nasais e mãos, respectivamente. Observou-se predomínio de fagotipos dos grupos I e III. Dos 12 portadores do microrganismo, concomitantemente em mãos e fossas nasais, 75,0% apresentaram cepas com vínculo epidemiológico. Os achados mostram o risco potencial representado pelas mãos nas intoxicações alimentares.Material was collected from the hands and nasal passages of forty-eight food handlers and twenty college students of Araraquara (S. Paulo State, Brazil and analized in order to evaluate the carrier function with regard to Staphylococcus aureus. The organism discovered in both samples of nine out of the twelve volunteers were of the same S. aureus phage types. The incidence of carriage on the hands was much greater in the handlers' group. These findings demonstrate the potential risk represented by hands in the transmission of food poisoning.

  2. Methicillin-resistant Staphylococcus aureus transmission

    DEFF Research Database (Denmark)

    Andersen, Leif Percival; Nielsen, Xiaohui

    2015-01-01

    increase the risk of contaminating hands, arms and the front of the uniform. Hand hygiene is therefore essential, but the use of protection gowns with long sleeves is also important in order to prevent transmission of MRSA. After culture of MRSA and implementation of specific precautions to prevent......INTRODUCTION: Even though methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of nosocomial infections, it may often be difficult to evaluate the exact route of transmission. METHODS: In this study, we describe four cases of nosocomial transmission of MRSA in a hospital with a low...... transmission of MRSA, no further transmissions were observed. FUNDING: not relevant. TRIAL REGISTRATION: The data in this study are included in the routine surveillance of MRSA at Rigshospitalet and do not form part of a trial....

  3. Bovine Staphylococcus aureus: Subtyping, evolution, and zoonotic transfer.

    Science.gov (United States)

    Boss, R; Cosandey, A; Luini, M; Artursson, K; Bardiau, M; Breitenwieser, F; Hehenberger, E; Lam, Th; Mansfeld, M; Michel, A; Mösslacher, G; Naskova, J; Nelson, S; Podpečan, O; Raemy, A; Ryan, E; Salat, O; Zangerl, P; Steiner, A; Graber, H U

    2016-01-01

    Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies using ribosomal spacer (RS)-PCR, however, demonstrated in Swiss cows that Staph. aureus isolated from bovine intramammary infections are genetically heterogeneous, with Staph. aureus genotype B (GTB) and GTC being the most prominent genotypes. Furthermore, Staph. aureus GTB was found to be contagious, whereas Staph. aureus GTC and all the remaining genotypes were involved in individual cow disease. In addition to RS-PCR, other methods for subtyping Staph. aureus are known, including spa typing and multilocus sequence typing (MLST). They are based on sequencing the spa and various housekeeping genes, respectively. The aim of the present study was to compare the 3 analytic methods using 456 strains of Staph. aureus isolated from milk of bovine intramammary infections and bulk tanks obtained from 12 European countries. Furthermore, the phylogeny of animal Staph. aureus was inferred and the zoonotic transfer of Staph. aureus between cattle and humans was studied. The analyzed strains could be grouped into 6 genotypic clusters, with CLB, CLC, and CLR being the most prominent ones. Comparing the 3 subtyping methods, RS-PCR showed the highest resolution, followed by spa typing and MLST. We found associations among the methods but in many cases they were unsatisfactory except for CLB and CLC. Cluster CLB was positive for clonal complex (CC)8 in 99% of the cases and typically positive for t2953; it is the cattle-adapted form of CC8. Cluster CLC was always positive for tbl 2645 and typically positive for CC705. For CLR and the remaining subtypes, links among the 3 methods were generally poor. Bovine Staph. aureus is highly clonal and a few clones predominate. Animal Staph. aureus always evolve from human strains, such that every human strain may be the ancestor of a novel animal-adapted strain. The zoonotic transfer of IMI- and milk-associated strains

  4. Identification of the ClpX Regulon in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Jelsbak, Lotte; Thomsen, Line Elnif; Ingmer, Hanne;

    Staphyloccous aureus is a major human pathogen capable of causing a wide spectrum of infections ranging from superficial wound infections to life-threatening endocarditis and toxic shock syndrome. Essential for S. aureus virulence is a large number of cell-surface-associated proteins and secreted...... we show here that almost 400 genes (15%) are influenced by the clpX deletion. Furthermore, ClpX not only regulates many virulence factors, but rather serves as a global regulator of central functions for S. aureus lifestyle and pathogenicity....

  5. Caracterización molecular de la región determinante de resistencia a quinolonas (QRDR de la topoisomerasa IV de Bartonella bacilliformis en aislados clínicos

    Directory of Open Access Journals (Sweden)

    Abraham Espinoza-Culupú

    2014-05-01

    Full Text Available Bartonella bacilliformis es el agente etiológico de la Enfermedad de Carrión, endémica del Perú. Pocas investigaciones han sido realizadas acerca de los genes asociados a la resistencia antimicrobiana en aislados clínicos de este patógeno. Estos genes no están caracterizados molecularmente, ni se conoce la región asociada a dicha resistencia. Por ello, el objetivo del este trabajo fue caracterizar molecularmente la región determinante de la resistencia a las quinolonas (QRDR en la topoisomerasa IV, que está codificada por los genes parC y parE, así como también desarrollar una prueba de susceptibilidad antimicrobiana para B. bacilliformis. Las muestras sanguíneas de 65 pacientes procedentes de La Libertad, Cusco, Ancash y Piura, se sembraron en placas de agar sangre e incubaron a 30 °C con 5% CO2. Luego se procedió a: (1 determinar la susceptibilidad antimicrobiana y (2 extraer el DNA genómico, amplificar los genes mencionados, secuenciarlos y analizarlos mediante herramientas bioinformáticas. Se obtuvieron 6 cultivos positivos. Los aislados fueron sensibles a la ciprofloxacina (excepto uno procedente de Quillabamba-Cusco, que presentó susceptibilidad disminuida y resistentes al ácido nalidíxico. Del análisis de las secuencias aminoacídicas de ParC y ParE de B. bacilliformis se concluye que presentan diferencias aminoacídicas en comparación con las secuencias de las proteínas respectivas de E. coli K12 MG1655, que probablemente confieran resistencia al ácido nalidíxico pero no a la ciprofloxacina. Se determinó que las QRDR de las proteínas ParC y ParE de B. bacilliformis están comprendidas entre los aminoácidos 67 al 118 y 473 al 530, respectivamente. El antibiograma y la concentración mínima inhibitoria se evalúan mejor usando inóculos a escala 1 de McFarland y a los 6 días de incubación.

  6. Genotipos de aislados de campo de Brucella abortus de distintas regiones geográficas de Chile Genotypes of Brucella abortus field isolates from different geographical regions of Chile

    Directory of Open Access Journals (Sweden)

    M Mancilla

    2008-01-01

    Full Text Available La brucelosis bovina es una enfermedad zoonótica, endémica de alto impacto económico. La identificación genética de las cepas prevalentes de Brucella abortus, el patógeno, es clave para establecer estrategias epidemiológicas de control de la enfermedad. La secuencia de inserción IS711 ha sido utilizada como un marcador genético para diferenciar entre especies de Brucella, miembros de una misma especie y dentro de un mismo biovar. Hemos analizado los perfiles de IS711-RFLP de 46 aislados de B. abortus, recolectados durante el periodo 1997-2005, provenientes de 16 áreas geográficas diferentes de Chile. Todos los aislados fueron previamente identificados como B. abortus biovar 1, utilizando las técnicas convencionales. De estos, el 87% compartieron el mismo perfil de IS711-RFLP, mientras que el 8,7% correspondió al patrón de la cepa vacuna RB51. En este trabajo se informa el hallazgo de dos cepas indistinguibles por PCR AMOS con perfiles nuevos de IS711-RFLP, no reportados previamente.Bovine brucellosis is an endemic, zoonotic disease of high economic impact. The genetic identification of the prevalent Brucella abortus strains, the pathogen, is key to pursue further epidemiological strategies for disease control. The insertion sequence IS711 has been used as genetic marker to differentiate among Brucella species, members of the same specie and within the same biovar. We have analyzed the IS711-RFLP pattern for 46 B. abortus isolates, collected during the period of 1997-2005 from 16 different geographical areas of Chile. All isolates were previously identified by conventional techniques as B. abortus biovar 1. Of these, 87% sharedthesame IS711 DNA profile, while an 8.7 % corresponded to the pattern of RB51 vaccine strain. We report the finding of two new strains, not differentiated by AMOS PCR, which showed unreported patterns of IS711-RFLP.

  7. Identificación de agentes etiológicos aislados de muestras biológicas en brote por intoxicación alimentaria en el departamento de Atlántico. Colombia. 2008

    Directory of Open Access Journals (Sweden)

    Guerra-Sarmiento Marlene

    2013-12-01

    Full Text Available Introduction: foodborne diseases constitute a worldwide problem of public health and generate a negative socio-economic impact. Objective: to identify the causal agent of an outbreak of food poisoning in a school cafeteria. Methods: Study carried out in people affected by a food poisoning in the municipality of Santo Tomas, Atlántico, Colombia, in the first semester of 2008. Phenotypic identification of 24 families of Staphylococcus aureus isolated from vomiting, fecal material, gastric juices, secretion of injury in finger and nasopharyngeal and pharyngeal secretion in schoolchildren and food handlers was carried out. Of these families, 15 were analyzed by means of PCR-RAPD (Random Amplified Polymorphic DNA technique. The products of PCR were visualized in agarose gels and analyzed by means of a dendogram. The similarity coefficient of Jaccard was calculated. Results: Coagulase-positive Staphylococcus aureus was identified in 16 samples of fecal material and Salmonella spp was recognized in two samples. In vomiting, 6 samples were positive for Coagulase-positive S. aureus and one sample for Salmonella spp. Also, Coagulase-positive S. aureus was isolated in a sample of secretion of nail and in nasopharyngeal secretion. Conclusion: Families of S. aureus with wide molecular diversity were identified. It constitutes the possible causal agent of an outbreak by food poisoing in a school cafeteria. Rev.cienc.biomed. 2013;4(2:233-241

  8. Estudios hematológicos y patológicos comparativos de cerdos inoculados con un aislado de campo y el serotipo 5 ATCC de Actinobacillus pleuropneumoniae Comparative hematological and pathological study of inoculated pigs with a field isolate and an ATCC serotype 5 of Actinobacillus pleuropneumoniae

    Directory of Open Access Journals (Sweden)

    D Muñoz

    2010-01-01

    Full Text Available Se realizó una inoculación experimental de A. pleuropneumoniae utilizando un aislado de campo y una cepa de referencia ATCC serotipo 5, para lo cual se utilizaron tres grupos de animales (n = 15 para cada grupo. El grupo 1 (G1 fue inoculado con medio estéril, el grupo (G2 con serotipo 5 ATCC y el grupo 3 (G3 fue inoculado con un aislado de campo (418/07. Los resultados mostraron diferencias significativas (P ≤ 0,05 en el recuento de leucocitos totales entre el grupo G1 v/s G2 y G1 v/s G3 y los grados de las lesiones pulmonares totales evidenciaron diferencias estadísticamente significativas (P ≤ 0,05 entre los tres grupos de estudio. Las lesiones histopatológicas pulmonares mostraron diferencias estadísticas relevantes sólo entre G1 y G3 (P ≤ 0,05. En este trabajo se verifican diferencias importantes del comportamiento entre el aislado de campo y el serotipo 5 ATCC, sobre los cambios hematológicos y las lesiones macroscópicas e histopatológicas ocasionadas por ellos, lo cual podría indicar una mayor virulencia y patogenicidad del aislado nacional. Se espera en un futuro próximo serotipificar este aislado nacional de App.An experimental inoculation of Actinobacillus pleuropneumoniae (App was carried out with a field isolate and an ATCC serotype 5. Three groups of 15 pigs each were used. Group 1 (G1 was the control group inoculated with sterile media, Group 2 was inoculated with the serotype 5 ATCC, and Group 3 (G3 was inoculated with a field isolate (418/07. The results showed statistically significant differences (P ≤ 0.05 in the total leukocytes count between G1 v/s G2 and G1 v/s G3. The total macroscopic lung lesions scores were statistically different among the 3 groups (P ≤ 0.05. However, statistical difference was found only between G1 and G3 in the histopathological lung lesions (P ≤ 0.05. This work shows a clear difference in the hematological changes and the macroscopic and histopathological lesions between the

  9. Separation of Staphylococcus aureus causing serious infections by electrophoretic techniques

    Czech Academy of Sciences Publication Activity Database

    Tesařová, Marie; Horká, Marie; Moravcová, Dana; Šťavíková, Lenka; Růžička, F.

    2014. s. 237-238. [Chemtech /14./. 22.10.2014-25.10.2014, Istambul] R&D Projects: GA MV VG20112015021 Institutional support: RVO:68081715 Keywords : Staphylococcus aureus * electrophoretic techniques Subject RIV: CB - Analytical Chemistry, Separation

  10. Improving Diagnosis and Treatment of Staphylococcus aureus Infections : Experimental Studies

    NARCIS (Netherlands)

    S. van den Berg (Sanne)

    2015-01-01

    markdownabstract__Abstract__ Staphylococcus aureus is an opportunistic pathogen that causes a variety of infections, ranging from mild skin infections like furuncles and impetigo, to severe, lifethreatening infections including endocarditis, osteomyelitis and pneumonia. Invasive infections are freq

  11. Staphylococcus aureus Peptidoglycan Tertiary Structure from Carbon-13 Spin Diffusion

    OpenAIRE

    Sharif, Shasad; Singh, Manmilan; Kim, Sung Joon; Schaefer,Jacob

    2009-01-01

    The cell-wall peptidoglycan of Staphylococcus aureus is a heterogeneous, highly cross-linked polymer of unknown tertiary structure. We have partially characterized this structure by measuring spin diffusion from 13C labels in pentaglycyl cross-linking segments to natural-abundance 13C in the surrounding intact cell walls. The measurements were performed using a version of centerband-only detection of exchange (CODEX). The cell walls were isolated from S. aureus grown in media containing [1-13...

  12. S. aureus bacteria : a new target of serum calcification activity

    OpenAIRE

    Dy, Diane Jazmin

    2009-01-01

    Staphylococcus aureus are gram- positive bacteria that cause skin and soft tissue infections. The continual incidence of infection is of great concern especially with the advent of methicillin resistant S. aureus (MRSA). Continued investigation on mechanisms our body uses to fight bacterial infection is vital. Our study suggests that the body takes advantage of a mechanism that mineralizes type-I collagen of bone and tendon to also mineralize bacteria. Serum driven bacterial mineralization ma...

  13. Comparative Pharmacodynamics of Gentamicin against Staphylococcus aureus and Pseudomonas aeruginosa†

    OpenAIRE

    Tam, Vincent H.; Kabbara, Samer; Vo, Giao; Schilling, Amy N.; Coyle, Elizabeth A.

    2006-01-01

    Aminoglycosides are often used to treat severe infections with gram-positive organisms. Previous studies have shown concentration-dependent killing by aminoglycosides of gram-negative bacteria, but limited data are available for gram-positive bacteria. We compared the in vitro pharmacodynamics of gentamicin against Staphylococcus aureus and Pseudomonas aeruginosa. Five S. aureus strains were examined (ATCC 29213 and four clinical isolates). Time-kill studies (TKS) in duplicate (baseline inocu...

  14. Role of Monocytes in Experimental Staphylococcus aureus Endocarditis

    OpenAIRE

    Veltrop, Marcel H. A. M.; Bancsi, Maurice J. L. M. F.; Bertina, Rogier M.; Thompson, Jan

    2000-01-01

    In the pathogenesis of bacterial endocarditis (BE), the clotting system plays a cardinal role in the formation and maintenance of the endocardial vegetations. The extrinsic pathway is involved in the activation of the coagulation pathway with tissue factor (TF) as the key protein. Staphylococcus aureus is a frequently isolated bacterium from patients with BE. We therefore investigated whether S. aureus can induce TF activity (TFA) on fibrin-adherent monocytes, used as an in vitro model of BE....

  15. Vancomycin Resistance Pattern of Staphylococcus Aureus among Clinical Samples

    OpenAIRE

    S Saadat; K Solhjoo; A. Kazemi; Erfanian, S. (MSc); Ashrafian, F. (MSc)

    2014-01-01

    Background and Objective: Vancomycin is used for treatment of methicillin-resistant S. Aureus (MRSA) infections; therefore, resistance to this antibiotic is increasing. We aimed to determine the antibiotic resistance pattern and frequency of vancomycin resistant S. Areas (VRSA) strains isolated from clinical samples. Material and Methods: In this cross-sectional study, 100 S. Aureus isolates collected from hospitals in Shiraz during six months, 2012, were identified by biochemical, microbiolo...

  16. AKTIVITAS ANTIBAKTERI KITOSAN TERHADAP BAKTERI S.aureus

    OpenAIRE

    Mardiyah Kurniasih; Dwi Kartika

    2009-01-01

    Chitosan is the N-deacetylated derivative of chitin. Chitosan is biodegradable, biocompatible and non-toxic. Chitosan is polycationic in acidic media and give antibacterial activity. In this paper, antibacterial activity of chitosan have been studied. Chitosan had been isolated from white shrimp. Antibacterial activity of chitosan solutions was examined against S. aureus The result showed that antimicrobial effect on S. aureus was strengthened as the choitosan concentrate decreased.

  17. Susceptibility of Staphylococcus aureus biofilms to reactive discharge gases

    OpenAIRE

    Traba, Christian; Liang, Jun F.

    2011-01-01

    Formation of bacterial biofilms at solid-liquid interfaces creates numerous problems in both industrial and biomedical sciences. In this study, the susceptibility of Staphylococcus aureus biofilms to discharge gas generated from plasma was tested. It was found that despite distinct chemical/physical properties, discharge gases from oxygen, nitrogen, and argon demonstrated very potent and almost the same anti-biofilm activity. The bacterial cells in S. aureus biofilms were killed (>99.9%) by d...

  18. Resistance to Antimicrobials Mediated by Efflux Pumps in Staphylococcus aureus

    OpenAIRE

    Isabel Couto; Leonard Amaral; José Melo-Cristino; Miguel Viveiros; Cláudia Palma; Elisabete Junqueira; Costa, Sofia S.

    2013-01-01

    Resistance mediated by efflux has been recognized in Staphylococcus aureus in the last few decades, although its clinical relevance has only been recognized recently. The existence of only a few studies on the individual and overall contribution of efflux to resistance phenotypes associated with the need of well-established methods to assess efflux activity in clinical isolates contributes greatly to the lack of solid knowledge of this mechanism in S. aureus. This study aims to provide inform...

  19. Methicillin resistance & inducible clindamycin resistance in Staphylococcus aureus

    OpenAIRE

    Soumyadeep Ghosh; Mandira Banerjee

    2016-01-01

    Background & objectives: Methicillin resistant Staphylococcus aureus (MRSA) isolates with inducible clindamycin resistance (iCR) are resistant to erythromycin and sensitive to clindamycin on routine testing and inducible clindamycin resistance can only be identified by D-test. This study was aimed to detect methicillin resistance and iCR among S. aureus isolates, effectiveness of some commonly used antibiotics and correlation between methicillin resistance and iCR. Methods: The present cro...

  20. Detection and characterization of mupirocin resistance in Staphylococcus aureus.

    OpenAIRE

    Janssen, D A; Zarins, L T; Schaberg, D R; Bradley, S. F.; Terpenning, M S; Kauffman, C A

    1993-01-01

    Fourteen mupirocin-resistant Staphylococcus aureus strains were isolated over 18 months; 12 exhibited low-level resistance, while two showed high-level resistance. Highly mupirocin-resistant strains contained a large plasmid which transferred mupirocin resistance to other S. aureus strains and to Staphylococcus epidermidis. This plasmid and pAM899-1, a self-transferable gentamicin resistance plasmid, have molecular and biologic similarities.

  1. Methicillin-Resistant Staphylococcus aureus Ocular Infection in Taiwan

    OpenAIRE

    Kang, Yu-Chuan; Hsiao, Ching-Hsi; Yeh, Lung-Kun; Ma, David H. K.; Chen, Phil Y. F.; Lin, Hsin-Chiung; Tan, Hsin-Yuan; Chen, Hung-Chi; Chen, Shin-Yi; Huang, Yhu-Chering

    2015-01-01

    Abstract Methicillin-resistant Staphylococcus aureus (MRSA) infection is an important public health issue. This observational study aimed to characterize clinical features, antibiotic susceptibility, and genotypes of ocular infections caused by MRSA based on the clinical and molecular definitions of community-associated (CA) and healthcare-associated (HA) strains. Fifty-nine patients with culture-proven S aureus ocular infection were enrolled from January 1, 2010 to December 31, 2011 at Chang...

  2. Resistance to Antimicrobials Mediated by Efflux Pumps in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Isabel Couto

    2013-03-01

    Full Text Available Resistance mediated by efflux has been recognized in Staphylococcus aureus in the last few decades, although its clinical relevance has only been recognized recently. The existence of only a few studies on the individual and overall contribution of efflux to resistance phenotypes associated with the need of well-established methods to assess efflux activity in clinical isolates contributes greatly to the lack of solid knowledge of this mechanism in S. aureus. This study aims to provide information on approaches useful to the assessment and characterization of efflux activity, as well as contributing to our understanding of the role of efflux to phenotypes of antibiotic resistance and biocide tolerance in S. aureus clinical isolates. The results described show that efflux is an important contributor to fluoroquinolone resistance in S. aureus and suggest it as a major mechanism in the early stages of resistance development. We also show that efflux plays an important role on the reduced susceptibility to biocides in S. aureus, strengthening the importance of this long neglected resistance mechanism to the persistence and proliferation of antibiotic/biocide-resistant S. aureus in the hospital environment.

  3. Photoreactivation of ultraviolet-irradiation damage in Staphylococcus aureus

    International Nuclear Information System (INIS)

    This study reports the capacity of Staphylococcus aureus strain 7 - 8 to undergo photoenzymatic repair of UV-irradiation induced damage and compares it to the photoreactivation (PR) response of Escherichia coli strain B. Staphylococcus aureaus showed greater inhibition by UV irradiation than E. coli, consistent with its higher adenine and thymine content of DNA. Staphylococcus aureus showed an enhanced rate of photoreactivation with no lag in initiation of the PR response at low PR doses compared to E. coli. Maximum PR capacity of both cultures was about equal and occurred in cultures incubated at 23 - 250. The PR responses at 11 - 12 and 35 - 370 for S. aureus and E. coli differed although both were capable of PR at each of these temperatures. The PR response of E. coli was directly related to the dosage of PR light (J/m2); however, the photoenzymatic capacity of S. aureus was not directly responsive to continued decrease in light intensity. The capacity of S. aureus to undergo liquid holding recovery (LHR) occurred at 23 - 250 (not at 11 - 120 or 35 - 370), whereas E. coli underwent LHR at 11 - 120 and 23 - 250 but not at 35 - 370. The LHR response of S. aureus was somewhat more effective than E. coli and did not show the direct response to increased liquid-holding period as did E. coli. (author)

  4. Staphylococcus aureus – antimicrobial resistance and the immunocompromised child

    Directory of Open Access Journals (Sweden)

    McNeil JC

    2014-05-01

    Full Text Available J Chase McNeilDepartment of Pediatrics, Section of Infectious Diseases, Baylor College of Medicine, Houston, TX, USAAbstract: Children with immunocompromising conditions represent a unique group for the acquisition of antimicrobial resistant infections due to their frequent encounters with the health care system, need for empiric antimicrobials, and immune dysfunction. These infections are further complicated in that there is a relative paucity of literature on the clinical features and management of Staphylococcus aureus infections in immunocompromised children. The available literature on the clinical features, antimicrobial susceptibility, and management of S. aureus infections in immunocompromised children is reviewed. S. aureus infections in children with human immunodeficiency virus (HIV are associated with higher HIV viral loads and a greater degree of CD4 T-cell suppression. In addition, staphylococcal infections in children with HIV often exhibit a multidrug resistant phenotype. Children with cancer have a high rate of S. aureus bacteremia and associated complications. Increased tolerance to antiseptics among staphylococcal isolates from pediatric oncology patients is an emerging area of research. The incidence of S. aureus infections among pediatric solid organ transplant recipients varies considerably by the organ transplanted; in general however, staphylococci figure prominently among infections in the early posttransplant period. Staphylococcal infections are also prominent pathogens among children with a number of immunodeficiencies, notably chronic granulomatous disease. Significant gaps in knowledge exist regarding the epidemiology and management of S. aureus infection in these vulnerable children.Keywords: pediatric, HIV, cancer, transplant

  5. Determining of antibiotic resistance profile inStaphylococcus aureus isolates

    Institute of Scientific and Technical Information of China (English)

    Hossein Motamedi; Hadis Mirzabeigi; Tahere Shirali

    2010-01-01

    Objective:To determine the pattern of antibiotic resistance amongStaphylococcus aureus (S. aureus) isolates from clinical specimens and to identify community-acquired methicillin-resistantStaphylococcus aureus(CA-MRSA)in specimens that have been collected from patients referring to one of the hospitals of Ahvaz.Methods:S. aureus isolates from a hospital in Ahvaz were screened for resistance to various antibiotics including methicillin. The susceptibility of the isolates was determined by Kirby-Bauer disc diffusion method. TheMRSA was also treated with ethidium bromide to find the origin of resistance.Results: Among the bacterial isolates, all of 11S. aureus were resistant to methicillin and cefixime,2 were resistant to ciprofloxacine,6 were resistant to tetracycline and the reminder were sensitive or intermediate to other antibiotics. The treated isolates were reminded resistant to methicillin and this suggested that the plasmid was not the origin of resistance in these isolates.Conclusions: These results showed that infection due toMRSA is widespread in Ahvaz and with respect to the spread of vancomycin resistance among MRSA and appearance of overwhelming infections. It is necessary to identify continuously the profile of antibiotic resistance amongS. aureus isolates in other regions and finding appropriate antibiotic for infection control and eradication.

  6. Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) at ambient freshwater beaches

    Science.gov (United States)

    Fogarty, Lisa R.; Haack, Sheridan K.; Johnson, Heather E.; Brennan, Angela K.; Isaacs, Natasha M.; Spencer, Chelsea

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) are a threat to human health worldwide, and although detected at marine beaches, they have been largely unstudied at freshwater beaches. Genes indicating S. aureus (SA; femA) and methicillin resistance (mecA) were detected at 11 and 12 of 13 US Great Lakes beaches and in 18% or 27% of 287 recreational water samples, respectively. Eight beaches had mecA + femA (potential MRSA) detections. During an intensive study, higher bather numbers, staphylococci concentrations, and femA detections were found in samples collected after noon than before noon. Local population density, beach cloud cover, and beach wave height were significantly correlated with SA or MRSA detection frequency. The Panton-Valentine leukocidin gene, associated with community-acquired MRSA, was detected in 12 out of 27 potential MRSA samples. The femA gene was detected less frequently at beaches that met US enterococci criteria or EU enterococci ‘excellent’ recreational water quality, but was not related to Escherichia coli-defined criteria. Escherichia coli is often the only indicator used to determine water quality at US beaches, given the economic and healthcare burden that can be associated with infections caused by SA and MRSA, monitoring of recreational waters for non-fecal bacteria such as staphylococci and/or SA may be warranted.

  7. Staphylococcus aureus small colony variants in diabetic foot infections.

    Science.gov (United States)

    Cervantes-García, Estrella; García-Gonzalez, Rafael; Reyes-Torres, Angélica; Resendiz-Albor, Aldo Arturo; Salazar-Schettino, Paz María

    2015-01-01

    Background : Staphylococcus aureus (S. aureus) is one of the major pathogens causing chronic infections. The ability of S. aureus to acquire resistance to a diverse range of antimicrobial compounds results in limited treatment options, particularly in methicillin-resistant S. aureus (MRSA). A mechanism by which S. aureus develops reduced susceptibility to antimicrobials is through the formation of small colony variants (SCVs). Infections by SCVs of S. aureus are an upcoming problem due to difficulties in laboratory diagnosis and resistance to antimicrobial therapy. Methods : A prospective study was performed on 120 patients diagnosed with both type 2 diabetes mellitus and infected diabetic foot ulcers. The study was carried out from July 2012 to December 2013 in Hospital General de Mexico. The samples were cultured in blood agar, mannitol salt agar, and MacConkey agar media, and incubated at 37°C in aerobic conditions. Results : We describe the first known cases of diabetic foot infections caused by MRSA-SCVs in patients diagnosed with type 2 diabetes mellitus and infected diabetic foot ulcers. In all of our cases, the patients had not received any form of gentamicin therapy. Conclusions : The antibiotic therapy commonly used in diabetic patients with infected diabetic foot ulcers fails in the case of MRSA-SCVs because the intracellular location protects S. aureus-SCVs from the host's defenses and also helps them resist antibiotics. The cases studied in this article add to the spectrum of persistent and relapsing infections attributed to MRSA-SCVs and emphasizes that these variants may also play a relevant role in diabetic foot infections. PMID:25787018

  8. Staphylococcus aureus small colony variants in diabetic foot infections

    Directory of Open Access Journals (Sweden)

    Estrella Cervantes-García

    2015-03-01

    Full Text Available Background: Staphylococcus aureus (S. aureus is one of the major pathogens causing chronic infections. The ability of S. aureus to acquire resistance to a diverse range of antimicrobial compounds results in limited treatment options, particularly in methicillin-resistant S. aureus (MRSA. A mechanism by which S. aureus develops reduced susceptibility to antimicrobials is through the formation of small colony variants (SCVs. Infections by SCVs of S. aureus are an upcoming problem due to difficulties in laboratory diagnosis and resistance to antimicrobial therapy. Methods: A prospective study was performed on 120 patients diagnosed with both type 2 diabetes mellitus and infected diabetic foot ulcers. The study was carried out from July 2012 to December 2013 in Hospital General de Mexico. The samples were cultured in blood agar, mannitol salt agar, and MacConkey agar media, and incubated at 37°C in aerobic conditions. Results: We describe the first known cases of diabetic foot infections caused by MRSA-SCVs in patients diagnosed with type 2 diabetes mellitus and infected diabetic foot ulcers. In all of our cases, the patients had not received any form of gentamicin therapy. Conclusions: The antibiotic therapy commonly used in diabetic patients with infected diabetic foot ulcers fails in the case of MRSA-SCVs because the intracellular location protects S. aureus-SCVs from the host's defenses and also helps them resist antibiotics. The cases studied in this article add to the spectrum of persistent and relapsing infections attributed to MRSA-SCVs and emphasizes that these variants may also play a relevant role in diabetic foot infections.

  9. A cohort study of the Copenhagen CF Centre eradication strategy against Staphylococcus aureus in patients with CF

    DEFF Research Database (Denmark)

    Dalbøge, Christina Schjellerup; Pressler, Tacjana; Høiby, Niels;

    2013-01-01

    Staphylococcus aureus is an important pathogen in CF. Centre prevalence of intermittent colonization and chronic S. aureus infections and the effectiveness of an anti-S. aureus eradication strategy was assessed....

  10. Radioimmunoassays for protein A of Staphylococcus aureus

    International Nuclear Information System (INIS)

    Radioimmunoassays have been developed that can detect nanogram amounts of protein A (SpA), a product generated by Staphylococcus aureus that binds selectively to the Fc region of IgG from most mammalian species. Competition assays for fluid phase SpA utilize antibodies produced in chickens, 125I-labeled SpA as the tracer molecule, and either F(ab')2 fragments of rabbit IgG anti-chicken IgG or 40% ammonium sulfate as the precipitating agent to separate antigen-antibody complexes from free antigen. The double antibody assay could be carried out in serum from species that form only soluble complexes with SpA (e.g., rabbit), that react poorly with SpA (e.g., rat) or under appropriate conditions in serum from species (e.g., dog) that show high reactivity with SpA and form precipitating complexes. Chicken antibodies prepared by affinity chromatography on SpA-Sepharose and labeled with 125I were used in a direct binding assay for SpA present either on the cell wall of Cowan strain I or Wood 46 bacteria, in insoluble complexes prepared from SpA and whole serum or purified IgG, or in C1q binding complexes that were formed by passage of serum from normal or tumor bearing humans or dogs over SpA-collodion charcoal. Since both types of assays could detect SpA even in the presence of serum or IgG, they offer advantages over other techniques in which the SpA-Fc interaction may interfere. (Auth.)

  11. A systematic review of animal models for Staphylococcus aureus osteomyelitis

    Directory of Open Access Journals (Sweden)

    W Reizner

    2014-03-01

    Full Text Available Staphylococcus aureus (S. aureus osteomyelitis is a significant complication for orthopaedic patients undergoing surgery, particularly with fracture fixation and arthroplasty. Given the difficulty in studying S. aureus infections in human subjects, animal models serve an integral role in exploring the pathogenesis of osteomyelitis, and aid in determining the efficacy of prophylactic and therapeutic treatments. Animal models should mimic the clinical scenarios seen in patients as closely as possible to permit the experimental results to be translated to the corresponding clinical care. To help understand existing animal models of S. aureus, we conducted a systematic search of PubMed and Ovid MEDLINE to identify in vivo animal experiments that have investigated the management of S. aureus osteomyelitis in the context of fractures and metallic implants. In this review, experimental studies are categorised by animal species and are further classified by the setting of the infection. Study methods are summarised and the relevant advantages and disadvantages of each species and model are discussed. While no ideal animal model exists, the understanding of a model’s strengths and limitations should assist clinicians and researchers to appropriately select an animal model to translate the conclusions to the clinical setting.

  12. Methicillin-resistant Staphylococcus aureus in central Iowa wildlife.

    Science.gov (United States)

    Wardyn, Shylo E; Kauffman, Lin K; Smith, Tara C

    2012-10-01

    Livestock and pets have been identified as carriers of Staphylococcus aureus; however, the role of wild animals as a reservoir of S. aureus strains has not yet been examined. We conducted a pilot study to determine the prevalence of methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) in 37 species of wild animals rehabilitated at a university clinic. Nasal, wing, wound, and cloacal swabs were collected. Of 114 animals, seven (6.1%) were MSSA-positive and three (2.6%) were MRSA-positive. The MRSA isolates were obtained from two eastern cottontail rabbits (Sylvilagus floridanus) and a Lesser Yellowlegs (Tringa flavipes), a migratory shorebird. Antibiotic resistance testing of the MRSA isolates revealed that two were additionally resistant to tetracycline and erythromycin, and the third isolate was also resistant to erythromycin, clindamycin, and levofloxacin. All three isolates were positive for the Panton-Valentine leukocidin (PVL) gene. Sequence typing of the staphylococcal protein A (spa) region revealed one MRSA isolate to be t002, whereas the other two MRSA isolates were found to be t008. Our results suggest that S. aureus, including MRSA, is being carried by wild animals, although at a low prevalence with the limited number of animals tested. Additional studies are needed to determine how this may impact human health. PMID:23060511

  13. Crystal Violet and XTT Assays on Staphylococcus aureus Biofilm Quantification.

    Science.gov (United States)

    Xu, Zhenbo; Liang, Yanrui; Lin, Shiqi; Chen, Dingqiang; Li, Bing; Li, Lin; Deng, Yang

    2016-10-01

    Staphylococcus aureus (S. Aureus) is a common food-borne pathogenic microorganism. Biofilm formation remains the major obstruction for bacterial elimination. The study aims at providing a basis for determining S. aureus biofilm formation. 257 clinical samples of S. aureus isolates were identified by routine analysis and multiplex PCR detection and found to contain 227 MRSA, 16 MSSA, 11 MRCNS, and 3 MSCNS strains. Two assays for quantification of S. aureus biofilm formation, the crystal violet (CV) assay and the XTT (tetrazolium salt reduction) assay, were optimized, evaluated, and further compared. In CV assay, most isolates formed weak biofilm 74.3 %), while the rest formed moderate biofilm (23.3 %) or strong biofilm (2.3 %). However, most isolates in XTT assay showed weak metabolic activity (77.0 %), while the rest showed moderate metabolic activity (17.9 %) or high metabolic activity (5.1 %). In this study, we found a distinct strain-to-strain dissimilarity in terms of both biomass formation and metabolic activity, and it was concluded from this study that two assays were mutual complementation rather than being comparison. PMID:27324342

  14. Enterotoxin production by Staphylococcus aureus isolated from mastitic cows.

    Science.gov (United States)

    Cenci-Goga, B T; Karama, M; Rossitto, P V; Morgante, R A; Cullor, J S

    2003-09-01

    Staphylococcus aureus is an important cause of mastitis in cows. The ability of S. aureus strains to produce one or more enterotoxins in milk and dairy products is linked to staphylococcal food poisoning. To determine whether staphylococci causing bovine mastitis could cause human foodborne intoxication, the production of staphylococcal enterotoxins A through D (SEA, SEB, SEC, and SED) by 160 S. aureus isolates was evaluated with the use of a reverse passive latex agglutination enterotoxin kit. All S. aureus strains were isolated over a 9-month period from 2,343 routine submissions of a composite quarter collection of individual mastitic cows at 18 dairy farms in the San Joaquin Valley in California. Prior to enterotoxin detection, isolates were grown by a method that enhances the in vitro synthesis of enterotoxin. Twenty-two of 160 S. aureus isolates produced enterotoxin. Seven produced SEC, 12 produced SED, and 3 produced both SEC and SED. None of the isolates produced SEA or SEB. PMID:14503727

  15. Prevalence of Salmonella and Staphylococcus aureus in chorizo and longaniza

    Directory of Open Access Journals (Sweden)

    Refugio Torres-Vitela

    2011-12-01

    Full Text Available Epidemiological research in developed and developing countries, had found meat products as the principal cause for foodbourne diseases. In addition, Salmonella and Staphyococcus aureus are well known pathogens for their mayor impact in public health. The objective for the present study consisted on determinate the sanitary quality from chorizo and longaniza samples from several butcheries in Guadalajara, Jalisco, Mexico. Samples of chorizo (50 and longaniza (50 were obtained from different points in Guadalajara metropolis. Presence of Salmonella and recounts for S. aureus were tested in 25 g samples. Procedure was followed according Mexican NOM 145-SSA1-1995 methods. In chorizo, 18 samples were positive to Salmonella. The count of S. aureus showed a mean of 24,600 UFC/g. On the other hand, 24 samples of longaniza were positive to Salmonella spp. In this case, the mean of S. aureus was 7,800 UFC/g. The serotypes of Salmonella spp were: Derby (30%, Adelaile (17%, Azteca (15%, Infantis (15%, Muenster(10% y Anatum (13 %. The high positivity of Salmonella spp. and S. aureus is a potential hazard to consumers.

  16. Analysis of similarity of the SI gene in infectious bronchitis virus (IBV isolates in Shanghai, China Análisis de similaridad del gen S1 de aislados del virus de la bronquitis infecciosa (IBV en Shanghai, China

    Directory of Open Access Journals (Sweden)

    J G Zhu

    2007-01-01

    Full Text Available The aim of the study was to analyze the similarity of the SI gene in 5 novel viral strains of infectious bronchitis virus (IBV isolated in Shanghai, China, using a pair of specific primers which were designed based on the published sequences of the S gene of IBV. The 5 full-length cDNA segments of the SI gene were amplified from the 5 isolated strains with RT-PCR. It was confirmed that the nucleotide sequences of the SI gene in the 5 strains isolated from chickens and pigeon have a length of 1626 bp and encode 541 amino acid residues. Compared to the sequence of selected reference IBV strains published in GenBank, the 4 strains from chickens exhibited 77.4%-82.9% identity in the SI gene sequence, with the deduced similarity of the protein sequence being 74.7%-82.6%, while the strain from pigeon exhibited 79.3%-99.6% similarity in the SI gene sequence, with a deduced identity of the protein sequence of 81.6%-99.6%. The SI protein cleavage site sequence of these isolates contains 5 consecutive basic amino acids, named, Arg-Arg-Phe-Arg-Arg (RRFRR similar to most of IBV strains. The results indicated that the variability range of the SI gene structure is high, corresponding with the biological character of IBV, and that molecularly the five isolated strains from Shanghai have a close relationship with the IBV reference strains. It was concluded that the five isolated strains belong to IBV, even though one of them was isolated from pigeonsEl objetivo del estudio fue analizar la similaridad del gen SI de 5 nuevas cepas virales del virus de la bronquitis infecciosa (IBV aislado en Shangai, China, para lo cual se usaron un par de partidores específicos, los cuales fueron designados en base a las secuencias publicadas del gen S del IBV. Los 5 segmentos completos de cDNA del gen SI fueron amplificados de las 5 cepas aisladas con RT-PCR. Se pudo confirmar que las secuencias de nucleótidos de genes SI en las 5 cepas aisladas de gallinas y palomas tienen

  17. Occurrence of Multidrug Resistant Staphylococcus aureus in horses in Malaysia

    Directory of Open Access Journals (Sweden)

    Z. Zunita

    2008-12-01

    Full Text Available A total of 22 Staphylococcus aureus were isolated from 50 samples from 8 stable horses. They are positive in the catalase and coagulase tests. Upon testing the cultures with SLIDEX test kit all formed agglutination within a few seconds, confirming they are of S. aureus. When cultured onto MSA, all isolates formed yellow colonies. However, none of the isolates produced blue colonies on ORSAB indicating that there were no MRSA among the S. aureus. There were 13 isolates which were multiresistant. Eleven are resistant to eight out of ten antibiotics tested. All these isolates were found to originate from stable G. One isolate is resistant to 5 antibiotics while another one isolate is resistant to 3 antibiotics. The rest of the isolates are not multiresistant to the antibiotics tested. [Veterinary World 2008; 1(6.000: 165-167

  18. Risk factors for Staphylococcus aureus nasal colonization in Danish middle-aged and elderly twins

    DEFF Research Database (Denmark)

    Andersen, P S; Larsen, Lisbeth Aagaard; Fowler, V G;

    2013-01-01

    Staphylococcus aureus is a human commensal bacterium found in the nasal cavity and other body sites. Identifying risk factors for S. aureus nasal carriage is of interest, as nasal carriage is a risk factor for subsequent invasive infection. We recently investigated the influence of host genetics...... on S. aureus carriage in Danish middle-aged and elderly twins, which indicated no significant heritability that could account for the observed S. aureus carriage. In the present study, we performed a questionnaire-based study of S. aureus colonization on the same cohort of 2,196 Danish middle......-aged and elderly twins to identify specific risk factors for S. aureus nasal colonization, including analyzing the paired twins (n = 478) that were discordant for S. aureus colonization. We found associations between risk factors and S. aureus nasal colonization among middle-aged and elderly twins, including age...

  19. Draft Genome Sequence of Methicillin-Sensitive Staphylococcus aureus ATCC 29213

    OpenAIRE

    Soni, Isha; Chakrapani, Harinath; Chopra, Sidharth

    2015-01-01

    Staphylococcus aureus subsp. aureus ATCC 29213 is one of the most commonly used strains in drug discovery research and for quality control. We report the completed draft genome sequence for the strain.

  20. Quality control of direct molecular diagnostics for methicillin-resistant Staphylococcus aureus.

    NARCIS (Netherlands)

    A.F. van Belkum (Alex); H.G.M. Niesters (Bert); W.G. MacKay (William); W.B. van Leeuwen (Willem)

    2007-01-01

    textabstractTen samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing. Sample

  1. Quality control of direct molecular diagnostics for methicillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    van Belkum, Alex; Niesters, Hubert G M; MacKay, William G; van Leeuwen, Willem B

    2007-01-01

    Ten samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing. Samples containing

  2. The Significance of Nasal Carriage of Staphylococcus Aureus and the Incidence of Postoperative Wound Infection

    NARCIS (Netherlands)

    R.P. Wenzel (Richard); T. M. Perl

    1995-01-01

    textabstractStaphylococcus aureus infections are associated with considerable morbidity and, in certain situations, mortality. The association between the nasal carriage of S. aureus and subsequent infection has been comprehensively established in a variety of clinical settings, in particular, patie

  3. Prevalence of infective endocarditis in patients with Staphylococcus aureus bacteraemia: the value of screening with echocardiography

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Høst, Ulla; Arpi, Magnus;

    2011-01-01

    Aims Staphylococcus aureus infective endocarditis (IE) is a critical medical condition associated with a high morbidity and mortality. In the present study, we prospectively evaluated the importance of screening with echocardiography in an unselected S. aureus bacteraemia (SAB) population. Methods...

  4. Characterization of Staphylococcus aureus infections in children with Down syndrome.

    Science.gov (United States)

    Johnston, Jeffrey N; Kaplan, Sheldon L; Mason, Edward O; Hulten, Kristina G

    2015-11-01

    Staphylococcus aureus infections in the Down syndrome (DS) population have not been well characterized. This study determined clinical and molecular characteristics of S. aureus infections in children with DS followed at Texas Children's Hospital (TCH), from 2001 to 2011. Patients were retrospectively identified from an ongoing S. aureus surveillance study. Medical records were reviewed. Isolates were characterized by antimicrobial susceptibility, pulsed-field gel electrophoresis patterns, and detection of PVL genes (pvl), mupA (high-level mupirocin resistance gene), smr (chlorhexidine resistance conferring gene), and Staphylococcal Chromosomal Cassette mec (SCCmec) type. Twenty-six patients with DS had a total of 34 S. aureus infections (8 recurrent); 61% were MRSA. DS patients represented 16.8 per 10,000 community onset S. aureus infections seen at TCH. Among 26 initial infections 17 were skin and soft tissue (SSTI), 7 were outer or middle ear and 2 were invasive infections. Seventeen patients were hospitalized. Thirteen (65%) of 20 available isolates were USA300, 14 were pvl+, 5 were mupA+, and 8 were smr+. Five of 8 (63%) recurrent infections were ear infections. All 4 recurrent ear isolates available for study were smr+, ciprofloxacin non-susceptible and treated with ciprofloxacin otic drops. S. aureus infections among patients with DS were similar in presentation to other patient groups, except for a greater proportion being associated with ear infections. Seventy percent of ear fluid isolates carried antiseptic and fluoroquinolone resistance genes. A study of a greater number of DS patients is warranted to further explore these findings. PMID:26386776

  5. Highly sensitive detection of Staphylococcus aureus directly from patient blood.

    Directory of Open Access Journals (Sweden)

    Padmapriya P Banada

    Full Text Available BACKGROUND: Rapid detection of bloodstream infections (BSIs can be lifesaving. We investigated the sample processing and assay parameters necessary for highly-sensitive detection of bloodstream bacteria, using Staphylococcus aureus as a model pathogen and an automated fluidic sample processing-polymerase chain reaction (PCR platform as a model diagnostic system. METHODOLOGY/PRINCIPAL FINDINGS: We compared a short 128 bp amplicon hemi-nested PCR and a relatively shorter 79 bp amplicon nested PCR targeting the S. aureus nuc and sodA genes, respectively. The sodA nested assay showed an enhanced limit of detection (LOD of 5 genomic copies per reaction or 10 colony forming units (CFU per ml blood over 50 copies per reaction or 50 CFU/ml for the nuc assay. To establish optimal extraction protocols, we investigated the relative abundance of the bacteria in different components of the blood (white blood cells (WBCs, plasma or whole blood, using the above assays. The blood samples were obtained from the patients who were culture positive for S. aureus. Whole blood resulted in maximum PCR positives with sodA assay (90% positive as opposed to cell-associated bacteria (in WBCs (71% samples positive or free bacterial DNA in plasma (62.5% samples positive. Both the assays were further tested for direct detection of S. aureus in patient whole blood samples that were contemporaneous culture positive. S. aureus was detected in 40/45 of culture-positive patients (sensitivity 89%, 95% CI 0.75-0.96 and 0/59 negative controls with the sodA assay (specificity 100%, 95% CI 0.92-1. CONCLUSIONS: We have demonstrated a highly sensitive two-hour assay for detection of sepsis causing bacteria like S. aureus directly in 1 ml of whole blood, without the need for blood culture.

  6. Untersuchungen zur Diagnostik und Epidemiologie von Staphylococcus aureus in Milchviehbetrieben in Brandenburg

    OpenAIRE

    Scheibe, Nicole

    2010-01-01

    The objective of this study was to analyse the epidemiological features of Staphylococcus (S.) aureus by using genotyping and antibiogram typing. Furthermore different methods for identification of S. aureus were performed to compare the methods’ ability to identify S. aureus from bovine milk. Milk samples were collected from six dairy herds with high prevalence of S. aureus in the federal state of Brandenburg, Germany. Of each herd, 32 cows in different stages of lactation and different a...

  7. In Vivo Activity of Ceftobiprole in Murine Skin Infections Due to Staphylococcus aureus and Pseudomonas aeruginosa▿

    OpenAIRE

    Fernandez, Jeffrey; Hilliard, Jamese J.; Abbanat, Darren; Zhang, Wenyan; Melton, John L.; Santoro, Colleen M.; Flamm, Robert K.; Bush, Karen

    2009-01-01

    Ceftobiprole, a broad-spectrum cephalosporin with activity against methicillin-resistant Staphylococcus aureus (MRSA) (P. Hebeisen et al., Antimicrob. Agents Chemother. 45:825-836, 2001), was evaluated in a subcutaneous skin infection model with Staphylococcus aureus Smith OC 4172 (methicillin-susceptible S. aureus [MSSA]), S. aureus OC 8525 (MRSA), Pseudomonas aeruginosa OC 4351 (having an inducible AmpC β-lactamase), and P. aeruginosa OC 4354 (overproducing AmpC β-lactamase). In the MSSA an...

  8. Investigation of the bactericidal effects of vancomycin and quinupristin/dalfopristin on Staphylococcus aureus isolates

    OpenAIRE

    HOŞGÖR-LİMONCU, Mine; ERMERTCAN, Şafak; COŞAR, Güner

    2004-01-01

    The present study aimed to determine the correlation between the bactericidal activity of vancomycin and quinupristin/dalfopristin (Q/D) on Staphylococcus aureus isolates and their minimal inhibition concentrations. The in-vitro susceptibilities of the 99 S. aureus isolates to vancomycin and Q/D were investigated by agar dilution. Thirty methicillin-resistant S. aureus (MRSA) and 30 methicillin-susceptible S. aureus (MSSA) vancomycin and Q/D susceptible isolates were involved in time-kill stu...

  9. Molecular Characterization and Antimicrobial Susceptibility of Nasal Staphylococcus aureus Isolates from a Chinese Medical College Campus

    OpenAIRE

    DU, JIMEI; Chen, Chun; Ding, Baixing; Tu, Jinjing; Qin, Zhiqiang; Parsons, Chris; Salgado, Cassandra; Cai, Qiangjun; SONG, Yulong; Bao, Qiyu; Zhang, Liming; Pan, Jingye; Wang, LiangXing; Yu, Fangyou

    2011-01-01

    Staphylococcus aureus colonization and infection occur more commonly among persons living or working in crowded conditions, but characterization of S. aureus colonization within medical communities in China is lacking. A total of 144 (15.4%, 144/935) S. aureus isolates, including 28 (3.0%, 28/935) MRSA isolates, were recovered from the nares of 935 healthy human volunteers residing on a Chinese medical college campus. All S. aureus isolates were susceptible to vancomycin, quinupristin/dalfopr...

  10. Daptomycin-nonsusceptible, vancomycin-intermediate, methicillin-resistant Staphylococcus aureus endocarditis

    OpenAIRE

    Ryan Yu; Dale, Suzanne E; Deborah Yamamura; Vida Stankus; Christine Lee

    2012-01-01

    Due to the emergence of Staphylococcus aureus with reduced vancomycin susceptibility, newer antibiotics, including daptomycin, have been used to treat methicillin-resistant S aureus infections. Daptomycin is a cyclic lipopeptide that is approved to treat S aureus bacteremia and right-sided endocarditis, and reports of S aureus with reduced susceptibility to daptomycin are infrequent. To our knowledge, the present report describes the first Canadian case of daptomycin-nonsusceptible, vancomyci...

  11. Human-associated Staphylococcus aureus strains within great ape populations in Central Africa (Gabon)

    OpenAIRE

    M. Nagel; Dischinger, J.; Türck, M.; Verrier, D.; Oedenkoven, M.; Ngoubangoye, B.; Le Flohic, G.; Drexler, J. F.; Bierbaum, G.; Gonzalez, Jean-Paul

    2013-01-01

    The risk of serious infections caused by Staphylococcus aureus is well-known. However, most studies regarding the distribution of (clinically relevant) S.aureus among humans and animals took place in the western hemisphere and only limited data are available from (Central) Africa. In this context, recent studies focused on S.aureus strains in humans and primates, but the question of whether humans and monkeys share related S.aureus strains or may interchange strains remained largely unsolved....

  12. Minimum inhibitory concentration of ciprofloxacin in combination with hexahydroquinoline derivatives against Staphylococcus aureus

    OpenAIRE

    F Amin Harati; Amini, M; AR Shahverdi; Pourmand MR; Yousefi, M

    2012-01-01

    Background: Staphylococcus aureus is the most common pathogen responsible for skin and soft tissue infections worldwide. Methicillin-resistant S. aureus is a major cause of both nosocomial and community acquired infections. The emergence of antimicrobial-resistant S. aureus is of global concern. Fluoroquinolone antimicrobials including ciprofloxacin, levofloxacin, and moxifloxacin are used to treat skin and soft tissue infections due to S. aureus. Emergence of ciprofloxacin resistance has inc...

  13. Methicillin-Resistant Staphylococcus aureus Colonization in Schoolteachers in Ontario

    Directory of Open Access Journals (Sweden)

    Beth A Hanselman

    2008-01-01

    Full Text Available A prospective study of methicillin-resistant Staphylococcus aureus (MRSA colonization was performed involving teachers at a science teachers’ conference in Toronto, Ontario. Nasal swabs and questionnaire data were collected from consenting individuals. MRSA colonization was identified in seven of 220 (3.2% participants. No colonized individuals reported recent contact with the health care system, antimicrobial therapy, residence with health care workers or previous MRSA infections. Methicillin-susceptible S aureus colonization was identified in 72 of 220 (33% individuals. The prevalence of MRSA colonization was higher than expected for a purportedly low-risk population.

  14. Genotyping of Staphylococcus aureus strains isolated from healthy persistent carriers.

    Science.gov (United States)

    Grzegorczyk, Agnieszka; Malm, Anna

    2014-07-01

    The paper presents results on the relatedness of Staphylococcus aureus strains colonizing the upper respiratory tract isolated from healthy persistent carriers. Genotyping was carried out using two methods--multiple-locus variable-number tandem-repeat fingerprinting (MLVF) and pulsed-field gel electrophoresis (PFGE). By comparison of the results obtained by both methods, good correlations between MLVF and PFGE genotyping of strains isolated from the asymptomatic carriers were observed. Further studies are needed to evaluate methods useful for genotyping of S. aureus strains circulating in the community. PMID:24488811

  15. Staphylococcus aureus sternal osteomyelitis: a rare cause of chest pain

    Directory of Open Access Journals (Sweden)

    Kaur M

    2015-10-01

    Full Text Available Chest pain is a common presenting symptom with a broad differential. Life-threatening cardiac and pulmonary etiologies of chest pain should be evaluated first. However, it is critical to perform a thorough assessment for other sources of chest pain in order to limit morbidity and mortality from less common causes. We present a rare case of a previously healthy 45 year old man who presented with focal, substernal, reproducible chest pain and Staphylococcus aureus bacteremia who was later found to have primary Staphylococcus aureus sternal osteomyelitis.

  16. Threat of multidrug resistant Staphylococcus aureus in Western Nepal

    DEFF Research Database (Denmark)

    Bhatta, Dharm R.; Cavaco, Lina; Nath, Gopal;

    2015-01-01

    ObjectiveTo determine the prevalence of methicillin resistant Staphylococcus aureus (MRSA) and antimicrobial susceptibility patterns of the isolates from Manipal Teaching Hospital, Pokhara, Nepal. MethodsThis study was conducted over a period of 11 months (September 2012–August 2013) at the Manipal...... using disc diffusion test by cefoxitin (30 μg) and oxacillin (1 μg) disc, further confirmation was done by detection of mecA gene using PCR. ResultsOut of 400 Staphylococcus aureus strains, 139 (34.75%) were found to be MRSA. Among the MRSA isolates, 74 (53.2%) were from inpatient departments, 58 (41...

  17. Capturing of staphylococcus aureus onto an interface containing graft chains

    International Nuclear Information System (INIS)

    A microbial-cell-capturing material was prepared by radiation-induced grafting of glycidyl methacrylate onto a polyethylene-based fiber before the introduction of diethylamine. The prepared fiber was tested against a Staphylococcus aureus and Escherichia coli solution. The results showed that the grafted-type fiber had a capturing rate constant 1000-fold higher than the commercial crosslinked-type bead for S. aureus and that an activation energy of 39 kJ/mol was obtained for the microbial-cell-capturing action. (author)

  18. Methicillin-resistant Staphylococcus aureus colonization in schoolteachers in Ontario.

    Science.gov (United States)

    Hanselman, Beth A; Kruth, Steven A; Rousseau, Joyce; Weese, J Scott

    2008-11-01

    A prospective study of methicillin-resistant Staphylococcus aureus (MRSA) colonization was performed involving teachers at a science teachers' conference in Toronto, Ontario. Nasal swabs and questionnaire data were collected from consenting individuals. MRSA colonization was identified in seven of 220 (3.2%) participants. No colonized individuals reported recent contact with the health care system, antimicrobial therapy, residence with health care workers or previous MRSA infections. Methicillin-susceptible S aureus colonization was identified in 72 of 220 (33%) individuals. The prevalence of MRSA colonization was higher than expected for a purportedly low-risk population. PMID:19436569

  19. Response of Staphylococcus Aureus to a Spaceflight Analogue

    Science.gov (United States)

    Castro, S. L.; Ott, C. M.

    2010-01-01

    The decreased gravity of the spaceflight environment creates quiescent, low fluid shear conditions. This environment can impart considerable effects on the physiology of microorganisms as well as their interactions with potential hosts. Using the rotating wall vessel (RWV), as a spaceflight analogue, the consequence of low fluid shear culture on microbial pathogenesis has provided a better understanding of the risks to the astronaut crew from infectious microorganisms. While the outcome of low fluid shear culture has been investigated for several bacterial pathogens, little has been done to understand how this environmental factor affects Staphylococcus aureus. S. aureus is an opportunistic human pathogen which presents a high level of infection risk to the crew, as it has been isolated from both the space shuttle and International Space Station. Given that approximately forty percent of the population are carriers of the bacteria, eradication of this organism from in flight environments is impractical. These reasons have lead to us to assess the response of S. aureus to a reduced fluid shear environment. Culture in the RWV demonstrated that S. aureus grown under the low-shear condition had lower cell concentrations after 10 hours when compared to the control culture. Furthermore, the low-shear cultured bacteria displayed a reduction in carotenoid production, pigments responsible for their yellow/gold coloration. When exposed to various environmental stressors, post low-shear culture, a decrease in the ability to survive oxidative assault was observed compared to control cultures. The low fluid shear environment also resulted in a decrease in hemolysin secretion, a staphylococcal toxin responsible for red blood cell lysis. When challenged by the immune components present in human whole blood, low-shear cultured S. aureus demonstrated significantly reduced survival rates as compared to the control culture. Assays to determine the duration of these alterations

  20. Mechanism of bacteriophage conversion of lipase activity in Staphylococcus aureus.

    OpenAIRE

    Lee, C Y; Iandolo, J J

    1985-01-01

    Staphylococcus aureus PS54 harbors two temperate bacteriophages and manifests no lipase activity on egg yolk agar. Curing of one of the resident prophages (L54a) restores lipase activity. To study the mechanism of bacteriophage conversion, the prophage was cured, and the gene encoding lipase activity was cloned into pBR322 in Escherichia coli on a 2.9-kilobase DNA fragment of the chromosome. The fragment was subcloned into a shuttle vector and subsequently transformed into S. aureus and Bacil...

  1. Estudio de la posible participación de la corriente IKATP en las modificaciones que sobre estabilidad y heterogeneidad miocárdica produce el ejercicio físico crónico, en corazón aislado, normalmente oxigenado y tras isquemia regional aguda.

    OpenAIRE

    Koninckx Cañada, Manuel

    2014-01-01

    El objetivo de la presente Tesis Doctoral ha sido valorar la posible participación del bloqueo del canal KATP en las modificaciones electrofisiológicas intrínsecas producidas por el ejercicio físico crónico, tanto en circunstancias de normal perfusión como, especialmente, durante la isquemia regional aguda. Para cumplimentar el objetivo comentado, nos hemos propuesto analizar, en corazón aislado y perfundido de conejo, las modificaciones producidas por la realización de ejercicio físico cróni...

  2. Integrones y su relación con el fenotipo de resistencia en bacilos gramnegativos aislados en el Hospital Torres Galdames de Iquique, Chile Integrons and their relationship with resistance phenotype in Gram negative bacilli isolated in the Hospital Torres Galdames, Iquique, Chile

    OpenAIRE

    Rubén Moraga M; Edgardo Santander P; Teresa Arias C; Fermín Méndez A

    2007-01-01

    La resistencia antimicrobiana es codificada por algunos elementos genéticos que generan un flujo horizontal, particularmente, en ambientes que están sometidos a una fuerte presión selectiva, como ocurre en el ambiente hospitalario. En tal sentido, los bacilos gramnegativos, en el último tiempo, han cobrado importancia como agentes de infección nosocomial. Objetivo. Investigar la presencia de integrones en aislados clínicos de bacilos gramnegativos y su relación con el fenotipo de resistencia,...

  3. Frequency of methicillin-resistant Staphylococcus aureus nasal colonization among patients suffering from methicillin resistant Staphylococcus aureus bacteraemia

    Science.gov (United States)

    Aslam, Nadia; Izhar, Mateen; Mehdi, Naima

    2013-01-01

    Objective: To determine rate of nasal colonization in Patients suffering from bacteraemia caused by methicillin resistant Staphylococcus aureus. Methods: This descriptive cross sectional study was carried out in a tertiary ca re, University Teaching Hospital (Shaikh Zayed Hospital, Lahore) from October 2010 to August 2011. Nasal swabs were taken from patients suffering from MRSA bacteraemia and were plated on mannitol salt agar plates to isolate Staphylococcus aureus (S. aureus) which were then tested for oxacillin susceptibility. Results: Nasal colonization was present in 52.5% of patients suffering from MRSA bacteraemia. Conclusion: Nasal colonization rates with MRSA were high among patients suffering from MRSA bacteraemia especially in those undergoing dialysis or surgical procedures. Therefore, screening and nasal decolonization should be practiced in hospitals. PMID:24550968

  4. Phenotypic and genotypic antimicrobial resistance traits of foodborne Staphylococcus aureus isolates from Shanghai

    Science.gov (United States)

    Staphylococcus aureus is a recognized pathogen in humans, which causes nosocomial infections and food poisoning. The transmission of antibiotic resistant S. aureus (ARSA), especially methicillin-resistant S. aureus (MRSA), between food products and humans has become a serious problem. Hence, it is n...

  5. Antimicrobial Susceptibility Pattern and Biochemical Characteristics of Staphylococcus aureus: Impact of Bio field Treatment

    OpenAIRE

    Mahendra Kumar Trivedi

    2015-01-01

    Study background: Staphylococci are widespread in nature, mainly found on the skin and mucous membranes. Staphylococcus aureus (S. aureus) is the key organism for food poisoning due to massive production of heat stable exotoxins. The current study was attempted to investigate the effect of biofield treatment on antimicrobial susceptibility pattern and biochemical characteristics of S. aureus (ATCC 25923).

  6. Nosocomial Infections and Drug Susceptibility Patterns in Methicillin Sensitive and Methicillin Resistant Staphylococcus aureus

    OpenAIRE

    Sharma, Nitish Kumar; Garg, Raina; Baliga, Shrikala; Bhat K., Gopalkrishna

    2013-01-01

    Aim: Staphylococcus aureus is one of the leading causes of nosocomial infections and is known for its ability to develop resistance to antibiotics. The drug susceptibility pattern of Methicillin Sensitive S. aureus (MSSA) and Methicillin Resistant S. aureus (MRSA) may vary.

  7. Staphylococcus aureus Strains That are Hypersusceptible to Resistance Gene Transfer from Enterococci▿

    OpenAIRE

    Sung, Julia M.-L.; Lindsay, Jodi A

    2007-01-01

    We identified naturally occurring Staphylococcus aureus mutants of the restriction modification pathway SauI, including bovine lineage ST151. In a model of vancomycin resistance transfer from Enterococcus faecalis, ST151 isolates are 500 times more susceptible than human S. aureus isolates. The eradication of “hyperrecipient” strains may reduce the evolution of vancomycin-resistant S. aureus.

  8. The population structure of Staphylococcus Aureus among general practice patients from The Netherlands.

    NARCIS (Netherlands)

    Donker, G.A.; Deurenberg, R.H.; Driessen, C.; Sebastian, S.; Nijs, S.; Stobberingh, E.E.

    2009-01-01

    To investigate the prevalence, the antibiotic resistance pattern and the population structure of Staphylococcus aureus, S. aureus isolates from the anterior nostrils of patients of general practitioners (GPs) were analysed. Insight into the S. aureus population structure is essential, as nasal carri

  9. Genome Sequences of Four Staphylococcus aureus Strains Isolated from Bovine Mastitis

    OpenAIRE

    Kant, Ravi; Taponen, Suvi; Koort, Joanna; Paulin, Lars; Åvall-Jääskeläinen, Silja; Palva, Airi

    2015-01-01

    Staphylococcus aureus is a major causative agent of mastitis in dairy cows. The pathogenicity of S. aureus may vary; it is able to cause severe clinical mastitis, but most often it is associated with chronic subclinical mastitis. Here, we present the genome assemblies of four S. aureus strains from bovine mastitis.

  10. Genome Sequences of Four Staphylococcus aureus Strains Isolated from Bovine Mastitis.

    Science.gov (United States)

    Kant, Ravi; Taponen, Suvi; Koort, Joanna; Paulin, Lars; Åvall-Jääskeläinen, Silja; Palva, Airi

    2015-01-01

    Staphylococcus aureus is a major causative agent of mastitis in dairy cows. The pathogenicity of S. aureus may vary; it is able to cause severe clinical mastitis, but most often it is associated with chronic subclinical mastitis. Here, we present the genome assemblies of four S. aureus strains from bovine mastitis. PMID:25908141

  11. Staphylococcus aureus with reduced susceptibility to vancomycin in healthcare settings.

    Science.gov (United States)

    Spagnolo, A M; Orlando, P; Panatto, D; Amicizia, D; Perdelli, F; Cristina, M L

    2014-12-01

    Glycopeptide resistance in Staphylococcus aureus is a source of great concern because, especially in hospitals, this class of antibiotics, particularly vancomycin, is one of the main resources for combating infections caused by methicillin-resistant Staphylococcus aureus strains (MRSA). Reduced susceptibility to vancomycin (VISA) was first described in 1996 in Japan; since then, a phenotype with heterogeneous resistance to vancomycin (h-VISA) has emerged. H-VISA isolates are characterised by the presence of a resistant subpopulation, typically at a rate of 1 in 10(5) organisms, which constitutes the intermediate stage betweenfully vancomycin-susceptible S. aureus (VSSA) and VISA isolates. As VISA phenotypes are almost uniformly cross-resistant to teicoplanin, they are also called Glycopeptides-intermediate Staphylococcus aureus strains (GISA) and, in the case of heterogeneous resistance to glycopeptides, h-GISA. The overall prevalence of h-VISA is low, accounting for approximately 1.3% of all MRSA isolates tested. Mortality due to h-GISA infections is very high (about 70%), especially among patients hospitalised in high-risk departments, such as intensive care units (ICU). Given the great clinical relevance of strains that are heteroresistant to glycopeptides and the possible negative impact on treatment choices, it is important to draw up and implement infection control practices, including surveillance, the appropriate use of isolation precautions, staff training, hand hygiene, environmental cleansing and good antibiotic stewardship. PMID:26137787

  12. Vancomycin-resistant Staphylococcus aureus: no apocalypse now.

    Science.gov (United States)

    Goldstein, F W; Kitzis, M D

    2003-08-01

    The number of reports concerning vancomycin-resistant Staphylococcus aureus is much higher than the number of true resistant strains or unexpected clinical failures. Many confounding factors, including inadequate serum levels, severely ill patients, foreign devices or undrained abscesses, are more likely to be responsible for the clinical failures than resistance to vancomycin. PMID:14616695

  13. Review on Panton Valentine leukocidin toxin carriage among Staphylococcus aureus.

    Science.gov (United States)

    Shrestha, B

    2013-09-01

    Panton Valentine leukocidin is a toxin making pores in the polymorphonuclear cells which is a virulence factor of some strains of Staphylococcus aureus. Initially it was produced by methicillin susceptible Staphylococcus aureus only. Later with the acquisition of mecA gene has lead it to be PVL positive methicillin resistant Staphylococcus aureus. Since MRSA are resistant to many antibiotics and further they produce a toxin the infections by PVL positive MRSA has become a challenge. PVL positive MRSA a virulent strain of drug resistant superbug MRSA that has spread around the world, has claimed many lives in UK, Europe, USA and Australia. Some strains of superbug attack the healthy young people and kill within 24 hrs. PVL positive Staphylococcus aureus has been reported to be associated with skin and soft tissue infections however they also cause invasive infections and necrotizing pneumonia. These microorganisms known to be community associated have spread to hospitals. Hospital acquired infection by such microorganisms lead to an increase in mortality hence should be controlled before they become prevalent in hospitals. PMID:24908537

  14. An Interdisciplinary Experiment: Azo-Dye Metabolism by "Staphylococcus Aureus"

    Science.gov (United States)

    Brocklesby, Kayleigh; Smith, Robert; Sharp, Duncan

    2012-01-01

    An interdisciplinary and engaging practical is detailed which offers great versatility in the study of a qualitative and quantitative metabolism of azo-dyes by "Staphylococcus aureus". This practical has broad scope for adaptation in the number and depth of variables to allow a focused practical experiment or small research project. Azo-dyes are…

  15. Increased risk of arterial thromboembolic events after Staphylococcus aureus bacteremia

    DEFF Research Database (Denmark)

    Mejer, N; Gotland, N; Uhre, M L;

    2015-01-01

    OBJECTIVES: An association between infection and arterial thromboembolic events (ATE) has been suggested. Here we examined the risk of myocardial infarction (MI), stroke and other ATE after Staphylococcus aureus bacteremia (SAB). METHODS: Danish register-based nation-wide observational cohort study...

  16. Pyrazole Based Inhibitors against Enzymes of Staphylococcus aureus

    DEFF Research Database (Denmark)

    Jagadeesan, G.; Vijayakuma, Vinodhkumar; Palayam, Malathy;

    2015-01-01

    agents. The current study focuses on molecular docking and dynamics studies of pyrazole derivatives against Nucleosidase and DNA gyrase B of Staphylococcus aureus. Molecular docking and dynamics studies reveal that some of these derivatives show better binding abilities than some of the current drugs...

  17. Killing of Staphylococcus aureus by C-8-Methoxy Fluoroquinolones

    OpenAIRE

    Zhao, Xilin; Wang, Jian-Ying; Xu, Chen; Dong, Yuzhi; Zhou, Jianfeng; Domagala, John; Drlica, Karl

    1998-01-01

    C-8-methoxy fluoroquinolones were more lethal than C-8-bromine, C-8-ethoxy, and C-8-H derivatives for Staphylococcus aureus, especially when topoisomerase IV was resistant. The methoxy group also increased lethality against wild-type cells when protein synthesis was inhibited. These properties encourage refinement of C-8-methoxy fluoroquinolones to kill staphylococci.

  18. Simple method for correct enumeration of Staphylococcus aureus.

    Science.gov (United States)

    Haaber, J; Cohn, M T; Petersen, A; Ingmer, H

    2016-06-01

    Optical density (OD) measurement is applied universally to estimate cell numbers of microorganisms growing in liquid cultures. It is a fast and reliable method but is based on the assumption that the bacteria grow as single cells of equal size and that the cells are dispersed evenly in the liquid culture. When grown in such liquid cultures, the human pathogen Staphylococcus aureus is characterized by its aggregation of single cells into clusters of variable size. Here, we show that aggregation during growth in the laboratory standard medium tryptic soy broth (TSB) is common among clinical and laboratory S. aureus isolates and that aggregation may introduce significant bias when applying standard enumeration methods on S. aureus growing in laboratory batch cultures. We provide a simple and efficient sonication procedure, which can be applied prior to optical density measurements to give an accurate estimate of cellular numbers in liquid cultures of S. aureus regardless of the aggregation level of the given strain. We further show that the sonication procedure is applicable for accurate determination of cell numbers using agar plate counting of aggregating strains. PMID:27080188

  19. Staphylococcus aureus redirects central metabolism to increase iron availability.

    Directory of Open Access Journals (Sweden)

    David B Friedman

    2006-08-01

    Full Text Available Staphylococcus aureus pathogenesis is significantly influenced by the iron status of the host. However, the regulatory impact of host iron sources on S. aureus gene expression remains unknown. In this study, we combine multivariable difference gel electrophoresis and mass spectrometry with multivariate statistical analyses to systematically cluster cellular protein response across distinct iron-exposure conditions. Quadruplicate samples were simultaneously analyzed for alterations in protein abundance and/or post-translational modification state in response to environmental (iron chelation, hemin treatment or genetic (Deltafur alterations in bacterial iron exposure. We identified 120 proteins representing several coordinated biochemical pathways that are affected by changes in iron-exposure status. Highlighted in these experiments is the identification of the heme-regulated transport system (HrtAB, a novel transport system which plays a critical role in staphylococcal heme metabolism. Further, we show that regulated overproduction of acidic end-products brought on by iron starvation decreases local pH resulting in the release of iron from the host iron-sequestering protein transferrin. These findings reveal novel strategies used by S. aureus to acquire scarce nutrients in the hostile host environment and begin to define the iron and heme-dependent regulons of S. aureus.

  20. Complete Genome Sequence of Staphylococcus aureus Siphovirus Phage JS01

    OpenAIRE

    Jia, Hongying; Bai, Qinqin; Yang, Yongchun; Yao, Huochun

    2013-01-01

    Staphylococcus aureus is the most prevalent and economically significant pathogen causing bovine mastitis. We isolated and characterized one staphylophage from the milk of mastitis-affected cattle and sequenced its genome. Transmission electron microscopy (TEM) observation shows that it belongs to the family Siphovirus. We announce here its complete genome sequence and report major findings from the genomic analysis.

  1. Natural Population Dynamics and Carriage of Staphylococcus aureus

    NARCIS (Netherlands)

    D.C. Melles (Damian)

    2008-01-01

    textabstractStaphylococcus aureus is a major human pathogen capable of causing a wide range of infections, from relatively mild skin infections such as folliculitis and furunculosis to life-threatening conditions, including sepsis, deep abscesses, pneumonia, osteomyelitis, and infective endocarditis

  2. THE STUDY OF RESISTENCE OF STAPHYLOCOCCUS AUREUS STRAINS TO ANTIMICROBIALS

    Directory of Open Access Journals (Sweden)

    Nazarchuk GG

    2012-12-01

    Full Text Available In the research work the results of the study of resistance forming to antibiotics, antiseptics and decametoxine composition with modified polysaccharides in S.aureus strains are presented. The development of resistance to penicillins, cephalosporins, glycopeptides, macrolides is shown. Slow forming of resistance to decasan and decametoxine composition with carboxymethylamylum, oxyethylcellulose was determined.

  3. Human Staphylococcus aureus lineages among Zoological Park residents in Greece

    Directory of Open Access Journals (Sweden)

    E. Drougka

    2015-10-01

    Full Text Available Staphylococcus aureus is a part of the microbiota flora in many animal species. The clonal spread of S. aureus among animals and personnel in a Zoological Park was investigated. Samples were collected from colonized and infected sites among 32 mammals, 11 birds and eight humans. The genes mecA, mecC, lukF/lukS-PV (encoding Panton-Valentine leukocidin, PVL and tst (toxic shock syndrome toxin-1 were investigated by PCR. Clones were defined by Multilocus Sequence Typing (MLST, spa type and Pulsed-Field Gel Electrophoresis (PFGE. Seven S. aureus isolates were recovered from four animals and one from an employee. All were mecA, mecC and tst–negative, whereas, one carried the PVL genes and was isolated from an infected Squirrel monkey. Clonal analysis revealed the occurrence of seven STs, eight PFGE and five spa types including ones of human origin. Even though a variety of genotypes were identified among S. aureus strains colonizing zoo park residents, our results indicate that colonization with human lineages has indeed occurred.

  4. Genetic Diversity of Staphylococcus aureus in Buruli Ulcer

    NARCIS (Netherlands)

    Amissah, Nana Ama; Glasner, Corinna; Ablordey, Anthony; Tetteh, Caitlin S.; Kotey, Nana Konama; Prah, Isaac; van der Werf, Tjip; Rossen, John W.; van Dijl, Jan Maarten; Stienstra, Ymkje

    2015-01-01

    Background Buruli ulcer (BU) is a necrotizing skin disease caused by Mycobacterium ulcerans. Previous studies have shown that wounds of BU patients are colonized with M. ulcerans and several other microorganisms, including Staphylococcus aureus, which may interfere with wound healing. The present st

  5. New insights into molecular typing methods for Staphylococcus aureus

    NARCIS (Netherlands)

    Ikawaty, R.

    2009-01-01

    Staphylococcus aureus (SA) remains a significant problem causing infections in both hospital and community settings. Methicillin-resistant SA (MRSA) continues to evolve and pose a great challenge through outbreaks and pandemic spread. Humans are no longer the only and the most important reservoir of

  6. Vancomycin-Resistant Staphylococcus aureus, Michigan, USA, 2007

    OpenAIRE

    Finks, Jennie; Wells, Eden; Dyke, Teri Lee; Husain, Nasir; Plizga, Linda; Heddurshetti, Renuka; Wilkins, Melinda; Rudrik, James; Hageman, Jeffrey; Patel, Jean; Miller, Corinne

    2009-01-01

    Vancomycin-resistant Staphylococcus aureus (VRSA) infections, which are always methicillin-resistant, are a rare but serious public health concern. We examined 2 cases in Michigan in 2007. Both patients had underlying illnesses. Isolates were vanA-positive. VRSA was neither transmitted to or from another known VRSA patient nor transmitted from patients to identified contacts.

  7. Virulence Factors and Antibiotic Susceptibility of Staphylococcus aureus Isolates in Ready-to-Eat Foods: Detection of S. aureus Contamination and a High Prevalence of Virulence Genes

    OpenAIRE

    Suat Moi Puah; Kek Heng Chua; Jin Ai Mary Anne Tan

    2016-01-01

    Staphylococcus aureus is one of the leading causes of food poisoning. Its pathogenicity results from the possession of virulence genes that produce different toxins which result in self-limiting to severe illness often requiring hospitalization. In this study of 200 sushi and sashimi samples, S. aureus contamination was confirmed in 26% of the food samples. The S. aureus isolates were further characterized for virulence genes and antibiotic susceptibility. A high incidence of virulence genes ...

  8. Expression and inducibility in Staphylococcus aureus of the mecA gene, which encodes a methicillin-resistant S. aureus-specific penicillin-binding protein.

    OpenAIRE

    Ubukata, K; Nonoguchi, R; Matsuhashi, M; Konno, M

    1989-01-01

    A beta-lactam-sensitive strain of Staphylococcus aureus could be converted to methicillin resistance by the introduction of a plasmid carrying the 4.3-kilobase HindIII chromosomal DNA fragment which encoded the mecA gene from a methicillin-resistant S. aureus. Transformant cells produced methicillin-resistant S. aureus-specific penicillin-binding protein constitutively, and additional insertion of an inducible penicillinase plasmid caused production of the pencillin-binding protein to become ...

  9. Complex network perspective on structure and function of Staphylococcus aureus metabolic network

    Indian Academy of Sciences (India)

    L Ying; D W Ding

    2013-02-01

    With remarkable advances in reconstruction of genome-scale metabolic networks, uncovering complex network structure and function from these networks is becoming one of the most important topics in system biology. This work aims at studying the structure and function of Staphylococcus aureus (S. aureus) metabolic network by complex network methods. We first generated a metabolite graph from the recently reconstructed high-quality S. aureus metabolic network model. Then, based on `bow tie' structure character, we explain and discuss the global structure of S. aureus metabolic network. The functional significance, global structural properties, modularity and centrality analysis of giant strong component in S. aureus metabolic networks are studied.

  10. Heme Recognition By a Staphylococcus Aureus IsdE

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, J.C.; Vermeiren, C.L.; Heinrichs, D.E.; Murphy, M.E.P.

    2009-06-03

    Staphylococcus aureus is a Gram-positive bacterial pathogen and a leading cause of hospital acquired infections. Because the free iron concentration in the human body is too low to support growth, S. aureus must acquire iron from host sources. Heme iron is the most prevalent iron reservoir in the human body and a predominant source of iron for S. aureus. The iron-regulated surface determinant (Isd) system removes heme from host heme proteins and transfers it to IsdE, the cognate substrate-binding lipoprotein of an ATP-binding cassette transporter, for import and subsequent degradation. Herein, we report the crystal structure of the soluble portion of the IsdE lipoprotein in complex with heme. The structure reveals a bi-lobed topology formed by an N- and C-terminal domain bridged by a single {alpha}-helix. The structure places IsdE as a member of the helical backbone metal receptor superfamily. A six-coordinate heme molecule is bound in the groove established at the domain interface, and the heme iron is coordinated in a novel fashion for heme transporters by Met{sup 78} and His{sup 229}. Both heme propionate groups are secured by H-bonds to IsdE main chain and side chain groups. Of these residues, His{sup 299} is essential for IsdE-mediated heme uptake by S. aureus when growth on heme as a sole iron source is measured. Multiple sequence alignments of homologues from several other Gram-positive bacteria, including the human pathogens pyogenes, Bacillus anthracis, and Listeria monocytogenes, suggest that these other systems function equivalently to S. aureus IsdE with respect to heme binding and transport.

  11. Characterization of a mouse-adapted Staphylococcus aureus strain.

    Science.gov (United States)

    Holtfreter, Silva; Radcliff, Fiona J; Grumann, Dorothee; Read, Hannah; Johnson, Sarah; Monecke, Stefan; Ritchie, Stephen; Clow, Fiona; Goerke, Christiane; Bröker, Barbara M; Fraser, John D; Wiles, Siouxsie

    2013-01-01

    More effective antibiotics and a protective vaccine are desperately needed to combat the 'superbug' Staphylococcus aureus. While in vivo pathogenicity studies routinely involve infection of mice with human S. aureus isolates, recent genetic studies have demonstrated that S. aureus lineages are largely host-specific. The use of such animal-adapted S. aureus strains may therefore be a promising approach for developing more clinically relevant animal infection models. We have isolated a mouse-adapted S. aureus strain (JSNZ) which caused a severe outbreak of preputial gland abscesses among male C57BL/6J mice. We aimed to extensively characterize this strain on a genomic level and determine its virulence potential in murine colonization and infection models. JSNZ belongs to the MLST type ST88, rare among human isolates, and lacks an hlb-converting phage encoding human-specific immune evasion factors. Naive mice were found to be more susceptible to nasal and gastrointestinal colonization with JSNZ than with the human-derived Newman strain. Furthermore, naïve mice required antibiotic pre-treatment to become colonized with Newman. In contrast, JSNZ was able to colonize mice in the absence of antibiotic treatment suggesting that this strain can compete with the natural flora for space and nutrients. In a renal abscess model, JSNZ caused more severe disease than Newman with greater weight loss and bacterial burden. In contrast to most other clinical isolates, JSNZ can also be readily genetically modified by phage transduction and electroporation. In conclusion, the mouse-adapted strain JSNZ may represent a valuable tool for studying aspects of mucosal colonization and for screening novel vaccines and therapies directed at preventing colonization. PMID:24023720

  12. Staphylococcus aureus phage types and their correlation to antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Mehndiratta P

    2010-10-01

    Full Text Available Context: Staphylococcus aureus is one of the most devastating human pathogen. The organism has a differential ability to spread and cause outbreak of infections. Characterization of these strains is important to control the spread of infection in the hospitals as well as in the community. Aim: To identify the currently existing phage groups of Staphylococcus aureus, their prevalence and resistance to antibiotics. Materials and Methods: Study was undertaken on 252 Staphylococcus aureus strains isolated from clinical samples. Strains were phage typed and their resistance to antibiotics was determined following standard microbiological procedures. Statistical Analysis: Chi square test was used to compare the antibiotic susceptibility between methicillin resistant Staph. aureus (MRSA and methicillin sensitive S. aureus (MSSA strains. Results: Prevalence of MRSA and MSSA strains was found to be 29.36% and 70.65% respectively. Of these 17.56% of MRSA and 40.44% of MSSA strains were community acquired. All the MSSA strains belonging to phage type 81 from the community were sensitive to all the antibiotics tested including clindamycin and were resistant to penicillin. Forty five percent strains of phage group III and 39% of non-typable MRSA strains from the hospital were resistant to multiple antibiotics. Conclusion: The study revealed that predominant phage group amongst MRSA strains was phage group III and amongst MSSA from the community was phage group NA (phage type 81. MSSA strains isolated from the community differed significantly from hospital strains in their phage type and antibiotic susceptibility. A good correlation was observed between community acquired strains of phage type 81 and sensitivity to gentamycin and clindamycin.

  13. Characterization of a mouse-adapted Staphylococcus aureus strain.

    Directory of Open Access Journals (Sweden)

    Silva Holtfreter

    Full Text Available More effective antibiotics and a protective vaccine are desperately needed to combat the 'superbug' Staphylococcus aureus. While in vivo pathogenicity studies routinely involve infection of mice with human S. aureus isolates, recent genetic studies have demonstrated that S. aureus lineages are largely host-specific. The use of such animal-adapted S. aureus strains may therefore be a promising approach for developing more clinically relevant animal infection models. We have isolated a mouse-adapted S. aureus strain (JSNZ which caused a severe outbreak of preputial gland abscesses among male C57BL/6J mice. We aimed to extensively characterize this strain on a genomic level and determine its virulence potential in murine colonization and infection models. JSNZ belongs to the MLST type ST88, rare among human isolates, and lacks an hlb-converting phage encoding human-specific immune evasion factors. Naive mice were found to be more susceptible to nasal and gastrointestinal colonization with JSNZ than with the human-derived Newman strain. Furthermore, naïve mice required antibiotic pre-treatment to become colonized with Newman. In contrast, JSNZ was able to colonize mice in the absence of antibiotic treatment suggesting that this strain can compete with the natural flora for space and nutrients. In a renal abscess model, JSNZ caused more severe disease than Newman with greater weight loss and bacterial burden. In contrast to most other clinical isolates, JSNZ can also be readily genetically modified by phage transduction and electroporation. In conclusion, the mouse-adapted strain JSNZ may represent a valuable tool for studying aspects of mucosal colonization and for screening novel vaccines and therapies directed at preventing colonization.

  14. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection.

    Directory of Open Access Journals (Sweden)

    Aisling F Brown

    Full Text Available Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI. These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans.

  15. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection.

    Science.gov (United States)

    Brown, Aisling F; Murphy, Alison G; Lalor, Stephen J; Leech, John M; O'Keeffe, Kate M; Mac Aogáin, Micheál; O'Halloran, Dara P; Lacey, Keenan A; Tavakol, Mehri; Hearnden, Claire H; Fitzgerald-Hughes, Deirdre; Humphreys, Hilary; Fennell, Jérôme P; van Wamel, Willem J; Foster, Timothy J; Geoghegan, Joan A; Lavelle, Ed C; Rogers, Thomas R; McLoughlin, Rachel M

    2015-01-01

    Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI). These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans. PMID:26539822

  16. Sensitive and rapid detection of staphylococcus aureus in milk via cell binding domain of lysin.

    Science.gov (United States)

    Yu, Junping; Zhang, Yun; Zhang, Yun; Li, Heng; Yang, Hang; Wei, Hongping

    2016-03-15

    Staphylococcus aureus (S. aureus) is an important food-borne pathogen in dairy products contaminated through raw ingredients or improper food handling. Rapid detection of S. aureus with high sensitivity is of significance for food quality and safety. In this study, a new method was developed for detecting S. aureus in milk by coupling immunomagnetic separation with enzyme linked cell wall binding domain (CBD) of lysin plyV12, which can bind to S. aureus with high affinity. There are millions of binding sites present on the cell surface of S. aureus for the CBD attachment, which greatly improves the detection sensitivity. The method has the overall testing time of only 1.5h with the detection limit of 4 × 10(3)CFU/mL in spiked milk. Because it is simple, rapid and sensitive, this method could be used for the detection of S. aureus in various food samples. PMID:26433070

  17. Antibiotic-mediated selection of quorum-sensing-negative Staphylococcus aureus

    DEFF Research Database (Denmark)

    Paulander, Wilhelm Erik Axel; Varming, Anders Nissen; Bæk, Kristoffer Torbjørn;

    2012-01-01

    -acquired S. aureus infections and suggest that the adaptability of S. aureus to antibiotics involves the agr locus. IMPORTANCE: Staphylococcus aureus is the most frequently isolated pathogen in intensive care units and a common cause of nosocomial infections, resulting in a high degree of morbidity and......Staphylococcus aureus is a human commensal that at times turns into a serious bacterial pathogen causing life-threatening infections. For the delicate control of virulence, S. aureus employs the agr quorum-sensing system that, via the intracellular effector molecule RNAIII, regulates virulence gene...... increases the agr-mediated fitness cost by inducing the expression of RNAIII. Thus, the extensive use of antibiotics in hospitals may explain why agr-negative variants are frequently isolated from hospital-acquired S. aureus infections but rarely found among community-acquired S. aureus strains. Importantly...

  18. Contribución al conocimiento de la morfología y taxonomía de un hongo del genero Prototrichia aislado de un cultivo de rosas

    Directory of Open Access Journals (Sweden)

    Correa de Restrepo Marina

    1996-06-01

    Full Text Available The macroscopic and microscopic morfology of an isolated fungus of rose cultivation were studied. It to find in fructification tipic form by half direct observation of macroscopic reproduction structure, this factor assign high stetic inconvenience for products commercial presentation and accept. After a review of the taxonomic literature, we placed it in the Prototrichia genus, of class mixomycetes, but not a particular species, for absence of necesary support to moment. We used the spore to spore technique add the nutritions cover-glass technique to secure the spore transfer and germination, and fungus development for the morfologic description; and by mounting in cover-glass of microscopic structure to study.Se estudio la morfología tanto macro como microscópica de un hongo aislado de plantas de rosas. Se encontró la fructificacion correspondiente a la forma asexual típica de la especie del género Prototrichia, no se conoce su papel ecológico, sinembargo podría afectar la presentación adecuada y para la aceptación a nivel comercial de las rosas. A partir de las muestras colectadas se realizaron estudios para su clasificación. Revisada la literatura pertinente se ubico dentro del genero Prototrichia de la clase Mixomycetes, pero no dentro de alguna especie en particular, por no disponerse de momento de las ayudas necesarias para tal fin; de este hongo no se tienen registros para el neotropico (Según Farr, M. L., 1976.Se siguieron las siguientes técnicas: Siembra de esporas (Espora a Espora, en medios de Agar - avena; siembra en lámina impregnada de material nutritivo para asegurar el traspaso y germinación de las esporas y desarrollo del hongo para su descripción morfológica microscópica, y se hicieron montajes en laminas de las estructuras a estudiar para la descripción microscópica.

  19. Shedding of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus from adult and pediatric bathers in marine waters

    Directory of Open Access Journals (Sweden)

    Sinigalliano Christopher D

    2011-01-01

    Full Text Available Abstract Background Staphylococcus aureus including methicillin resistant S. aureus, MRSA, are human colonizing bacteria that commonly cause opportunistic infections primarily involving the skin in otherwise healthy individuals. These infections have been linked to close contact and sharing of common facilities such as locker rooms, schools and prisons Waterborne exposure and transmission routes have not been traditionally associated with S. aureus infections. Coastal marine waters and beaches used for recreation are potential locations for the combination of high numbers of people with close contact and therefore could contribute to the exposure to and infection by these organisms. The primary aim of this study was to evaluate the amount and characteristics of the shedding of methicillin sensitive S. aureus, MSSA and MRSA by human bathers in marine waters. Results Nasal cultures were collected from bathers, and water samples were collected from two sets of pools designed to isolate and quantify MSSA and MRSA shed by adults and toddlers during exposure to marine water. A combination of selective growth media and biochemical and polymerase chain reaction analysis was used to identify and perform limited characterization of the S. aureus isolated from the water and the participants. Twelve of 15 MRSA isolates collected from the water had identical genetic characteristics as the organisms isolated from the participants exposed to that water while the remaining 3 MRSA were without matching nasal isolates from participants. The amount of S. aureus shed per person corresponded to 105 to 106 CFU per person per 15-minute bathing period, with 15 to 20% of this quantity testing positive for MRSA. Conclusions This is the first report of a comparison of human colonizing organisms with bacteria from human exposed marine water attempting to confirm that participants shed their own colonizing MSSA and MRSA into their bathing milieu. These findings clearly

  20. Antimicrobial potential of Pakistani medicinal plants against multi-drug resistance Staphylococcus aureus

    Institute of Scientific and Technical Information of China (English)

    Rahat Ejaz; Usman A Ashfaq; Sobia Idrees

    2014-01-01

    Objective: To determine resistance patterns of Staphylococcus aureus (S. aureus) isolated from different areas of Pakistan and to identify antimicrobial agents against multi-drug resistant S.aureus strains. Methods: A total of 67 samples (sewerage, nasal and milk) were collected from different farm areas of Pakistan to identify local strains of S. aureus. Sixteen out of 67 samples were positive for S.aureus. Only 6 out of 16 S. aureus strains showed resistance to antibiotics. Then the antibacterial effect of 29 medicinal plants was evaluated on these S. aureus isolates and a standard S. aureus strain ATCC 25923. The solvents used for the extraction of plants were acetone, dimethyl sulfoxide and methanol. The in vitro antibacterial activity was performed using agar disc diffusion method. Moreover, minimum inhibitory concentration of effective medicinal plant extracts was identified through micro-dilution method to find out their 50% inhibitory concentration.Results:Plant extracts of 5 medicinal plants (Psidium guajava, Nigella sativa, Piper nigrum, Valeriana jatamansi, and Cucurbita pepo) exhibited antibacterial activity against locally isolated multidrug resistant strains of S. aureus. The minimum inhibitory concentration of these extracts was ranged from 0.328 to 5.000 mg/mL. Conclusions: Plant extracts of Psidium guajava, Piper nigrum seed, Valeriana jatamansi, Cucurbita pepo and Nigella sativa showed significant in vitro antibacterial activity and thus, such findings may serve as valuable contribution in the treatment of infection and may contribute to the development of potential antimicrobial agents against multi drug resistant strains of S. aureus.

  1. Antimicrobial potential of Pakistani medicinal plants against multi-drug resistance Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Rahat Ejaz

    2014-09-01

    Full Text Available Objective: To determine resistance patterns of Staphylococcus aureus (S. aureus isolated from different areas of Pakistan and to identify antimicrobial agents against multi-drug resistant S. aureus strains. Methods: A total of 67 samples (sewerage, nasal and milk were collected from different farm areas of Pakistan to identify local strains of S. aureus. Sixteen out of 67 samples were positive for S. aureus. Only 6 out of 16 S. aureus strains showed resistance to antibiotics. Then the antibacterial effect of 29 medicinal plants was evaluated on these S. aureus isolates and a standard S. aureus strain ATCC 25923. The solvents used for the extraction of plants were acetone, dimethyl sulfoxide and methanol. The in vitro antibacterial activity was performed using agar disc diffusion method. Moreover, minimum inhibitory concentration of effective medicinal plant extracts was identified through micro-dilution method to find out their 50% inhibitory concentration. Results: Plant extracts of 5 medicinal plants (Psidium guajava, Nigella sativa, Piper nigrum, Valeriana jatamansi, and Cucurbita pepo exhibited antibacterial activity against locally isolated multidrug resistant strains of S. aureus. The minimum inhibitory concentration of these extracts was ranged from 0.328 to 5.000 mg/mL. Conclusions: Plant extracts of Psidium guajava, Piper nigrum seed, Valeriana jatamansi, Cucurbita pepo and Nigella sativa showed significant in vitro antibacterial activity and thus, such findings may serve as valuable contribution in the treatment of infection and may contribute to the development of potential antimicrobial agents against multi drug resistant strains of S. aureus

  2. Portación de Staphylococcus aureus enterotoxigénicos en manipuladores de alimentos Carriage of enterotoxigenic Staphylococcus aureus in food handlers

    Directory of Open Access Journals (Sweden)

    Guillermo Figueroa G

    2002-08-01

    Full Text Available Background: One of the most common pathogens causing alimentary toxi-infections is Staphylococcus aureus (S aureus. The presence of S aureus in food, indicates flaws during food manipulations. For this reason most sanitary norms require the detection of S aureus carriers. Aim: To determine the carriage rate of enterotoxin producing S aureus strains in food handlers, and to evaluate the antibiotic susceptibility to six antimicrobial agents. Materials and Methods: A total of 102 food handlers from 19 restaurants in Santiago, were analyzed. Samples for microbiological analysis were obtained with a swab from the retropharynx. Results: S aureus grew in 35 out of the 102 samples obtained (34%. Further analysis revealed that 19/35 (54% strains were able to produce enterotoxins. Therefore the corrected carriage rate was 19% (19/102. The most frequently detected enterotoxin was the type A (12/19. All S aureus isolates were resistant to penicillin and susceptible to oxacillin, clindamycin, kanamycin, vancomycin and linezolid. Conclusions: The carriage rate of S aureus in food handlers is similar to the rate reported in the general population in our country. These results confirm the need for education and training programs in food safety, directed to food handlers (Rev Méd Chile 2002; 130: 859-64

  3. Mastitis Bovina: Resistencia a antibióticos de cepas de Staphylococcus aureus asiladas de leche (Bovine Mastitis: Antimicrobial resistance of Staphylococcus aureus strains isolated from milk)

    OpenAIRE

    Pellegrino, MS; Frola, ID; Odierno, LM; Bogni, CI

    2011-01-01

    ResumenLa mastitis bovina es considerada la enfermedad infecciosa del ganado lechero de mayor impacto económico mundial, siendo Staphylococcus aureus el principal agente patógeno en muchos países.SummaryBovine mastitis is a frequent cause of economic loss in worldwide dairy herds, being Staphylococcus aureus the main etiological agent in many countries.

  4. Mastitis Bovina: Resistencia a antibióticos de cepas de Staphylococcus aureus asiladas de leche (Bovine Mastitis: Antimicrobial resistance of Staphylococcus aureus strains isolated from milk

    Directory of Open Access Journals (Sweden)

    Pellegrino, MS

    2011-07-01

    Full Text Available ResumenLa mastitis bovina es considerada la enfermedad infecciosa del ganado lechero de mayor impacto económico mundial, siendo Staphylococcus aureus el principal agente patógeno en muchos países.SummaryBovine mastitis is a frequent cause of economic loss in worldwide dairy herds, being Staphylococcus aureus the main etiological agent in many countries.

  5. Cavity Forming Pneumonia Due to Staphylococcus aureus Following Dengue Fever.

    Science.gov (United States)

    Miyata, Nobuyuki; Yoshimura, Yukihiro; Tachikawa, Natsuo; Amano, Yuichiro; Sakamoto, Yohei; Kosuge, Youko

    2015-11-01

    While visiting Malaysia, a 22-year-old previously healthy Japanese man developed myalgia, headache, and fever, leading to a diagnosis of classical dengue fever. After improvement and returning to Japan after a five day hospitalization, he developed productive cough several days after defervescing from dengue. Computed tomography (CT) thorax scan showed multiple lung cavities. A sputum smear revealed leukocytes with phagocytized gram-positive cocci in clusters, and grew an isolate Staphylococcus aureus sensitive to semi-synthetic penicillin; he was treated successfully with ceftriaxone and cephalexin. This second reported case of pneumonia due to S. aureus occurring after dengue fever, was associated both with nosocomial exposure and might have been associated with dengue-associated immunosuppression. Clinicians should pay systematic attention to bacterial pneumonia following dengue fever to establish whether such a connection is causally associated. PMID:26304914

  6. Schistosoma spindale infection in a captive jackal (Canis aureus)

    OpenAIRE

    Vimalraj, P. G.; Latchumikanthan, A.

    2013-01-01

    This report is based on the findings from a captive jackal (Canis aureus) housed in Amirthi Zoological Park, Javadu Hills, Vellore. The animal was reported to be dull, depressed and also had diarrhea. Fecal samples were collected in 10 % formalin and subjected to direct and sedimentation method of faecal examination and was examined for endoparasitic infection. Surprisingly, fecal examination revealed two spindle shaped eggs having terminal spine with a size of 250μ by 60μ. The eggs were iden...

  7. Acral lick dermatitis in a jackal (Canis aureus).

    Science.gov (United States)

    Yeruham, I; Nyska, A

    1998-06-01

    Acral lick dermatitis was diagnosed in a 6-mo-old female jackal (Canis aureus) that was born and housed in a zoological garden in Hafez-Haim, Israel. Other dermatologic diseases were ruled out. Although the lesions were presumed to be psychogenic in origin, they resolved with topical therapy using an ointment containing benzocaine, neomycin sulfate, and hydrocortisone acetate. No recurrence has been observed. PMID:9732044

  8. Methicillin resistant Staphylococcus aureus (MRSA) in the intensive care unit

    OpenAIRE

    Haddadin, A; Fappiano, S; Lipsett, P

    2002-01-01

    Methicillin resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen that causes severe morbidity and mortality worldwide. MRSA strains are endemic in many American and European hospitals and account for 29%–35% of all clinical isolates. Recent studies have documented the increased costs associated with MRSA infection, as well as the importance of colonisation pressure. Surveillance strategies have been proposed especially in high risk areas such as the intensive care unit. Pneum...

  9. CHARACTERIZATION OF HOSPITAL ACQUIRED METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS

    OpenAIRE

    Preethi. B.M; J.Vimalin Hena

    2012-01-01

    Methicillin Resistant Staphylococcus aureus (MRSA) strains have emerged as one of the most important nosocomial pathogens. The MRSA can cause a wide range of diseases, which is associated with its production to large number of extracellular toxins and other virulence factors. The diseases are toxic shock syndrome, scalded skin syndrome and food poisoning. Hospital-acquired MRSA (HA-MRSA) in persons who have had frequent or recent contact with hospitals or healthcare facilities within the prev...

  10. Diversity of Prophages in Dominant Staphylococcus aureus Clonal Lineages▿

    OpenAIRE

    Goerke, Christiane; Pantucek, Roman; Holtfreter, Silva; Schulte, Berit; Zink, Manuel; Grumann, Dorothee; Barbara M. Bröker; Doskar, Jiri; Wolz, Christiane

    2009-01-01

    Temperate bacteriophages play an important role in the pathogenicity of Staphylococcus aureus, for instance, by mediating the horizontal gene transfer of virulence factors. Here we established a classification scheme for staphylococcal prophages of the major Siphoviridae family based on integrase gene polymorphism. Seventy-one published genome sequences of staphylococcal phages were clustered into distinct integrase groups which were related to the chromosomal integration site and to the enco...

  11. Quinupristin/dalfopristin in Staphylococcus aureus endophthalmitis: a case report

    OpenAIRE

    Hernandez-Da Mota Sergio E

    2011-01-01

    Abstract Introduction The intravitreal injection of antibiotics remains the mainstay of therapy for postoperative endophthalmitis. Bacterial resistance, however, is still a pitfall in achieving an adequate response to treatment. Quinupristin/dalfopristin might be a feasible therapeutic option in these cases. Case presentation A 55-year-old Hispanic man had endophthalmitis secondary to Staphylococcus aureus in his right eye and was treated with intravitreal 0.4 mg/0.1 ml quinupristin/dalfopris...

  12. Fatal pneumoni med Panton-Valentine-leukocidinproducerende Staphylococcus aureus

    DEFF Research Database (Denmark)

    Rabøl, Peter Hedelund; Dessau, Ram Benny; Warnecke, Mads;

    2010-01-01

    We describe a case of fatal pneumonia in a previously healthy 14-year-old boy. The patient was severely affected at the time of admission with high fever, tachypnea, tachycardia and peripheral cyanosis. The condition worsened despite treatment with antibiotics as well as respiratory and pressure ...... support. Acidosis and critical leucopenia supervened and the patient died just short of 24 hours after admission. Subsequent bacterial cultivation showed Panton-Valentine Leucocidin-producing Staphylococcus aureus....

  13. Quinolone accumulation in Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus.

    OpenAIRE

    McCaffrey, C; Bertasso, A; Pace, J.; Georgopapadakou, N H

    1992-01-01

    The accumulation of quinolones by Escherichia coli JF568, Pseudomonas aeruginosa PAO1, and Staphylococcus aureus ATCC 29213 was measured by a modified fluorometric assay (J. S. Chapman and N. H. Georgopapadakou, Antimicrob. Agents Chemother. 33:27-29, 1989). The quinolones examined were fleroxacin, pefloxacin, norfloxacin, difloxacin, A56620, ciprofloxacin, ofloxacin, and Ro 09-1168. In all three organisms, uptake was complete in less than 5 min and was proportional to extracellular quinolone...

  14. Bactericidal antibiotic-phytochemical combinations against methicillin resistant Staphylococcus aureus

    OpenAIRE

    Bhone Myint Kyaw; Shuchi arora; Chu Sing Lim

    2012-01-01

    Methicillin resistant Staphylococcus aureus (MRSA) infection is a global concern nowadays. Due to its multi-drug resistant nature, treatment with conventional antibiotics does not assure desired clinical outcomes. Therefore, there is a need to find new compounds and/or alternative methods to get arsenal against the pathogen. Combination therapies using conventional antibiotics and phytochemicals fulfill both requirements. In this study, the efficacy of different phytochemicals in combination ...

  15. Coated vesicle isolation by immunoadsorption on Staphylococcus aureus cells

    OpenAIRE

    1982-01-01

    Porcine brain coated vesicles were isolated from crude fractions of tissue homogenates by affinity separation using anticlathrin-coated STaphylococcus aureus (Staph A) cells as a solid-phase immunoadsorbent. The specificity of the immunoadsorption was monitored by SDS PAGE analysis and by competitive ELISA assays. SDS PAGE of the material immunoadsorbed from a fraction of porcine bran smooth microsomes showed a selective enrichment in a 180,000 mol wt protein. In an ELISA assay, this protein ...

  16. Immunoprophylaxis of Staphylococcus aureus mastitis in diary cows

    OpenAIRE

    Vakanjac Slobodanka; Pavlović M.; Pavlović V.; Obrenović Sonja

    2008-01-01

    Mastitis in cows represents one of the most actual problems in intensive dairy production. The prevention of pathogen penetration in the udder, its colonization and reproduction impose the constant need for regular milk check-ups, and preventive and therapeutic measures. Staphylococcus aureus causes subclinical and clinical mastitis, which when in the acute form can originate difficult and malignant udder infections with granulomatous and necrotic changes. Chronic forms of Staphylococcal mast...

  17. Personal Hygiene and Methicillin-resistant Staphylococcus aureus Infection

    OpenAIRE

    Turabelidze, George; Lin, Mei; Wolkoff, Barbara; Dodson, Douglas; Gladbach, Stephen; Zhu, Bao-Ping

    2006-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections outside the healthcare setting are an increasing concern. We conducted a case-control study to investigate an MRSA outbreak during 2002–2003 in a Missouri prison and focused on hygiene factors. Information on sociodemographic characteristics, medical history, and hygiene practices of study participants was collected by interview and medical record review. Logistic regression was used to evaluate MRSA infection in relation to hygien...

  18. Determination of aminoglycoside resistance in Staphylococcus aureus by DNA hybridization.

    OpenAIRE

    Dickgiesser, N; Kreiswirth, B N

    1986-01-01

    A method is described for identification of the genes conferring aminoglycoside resistance in Staphylococcus aureus by dot-blot and Southern blot techniques. As radioactive probes, fragments of plasmids pAT48, pUBH2, and pH13, carrying the genes for an aminocyclitol-3'-phosphotransferase, an aminocyclitol-4'-adenylyltransferase, and an aminocyclitol-2''-phosphotransferase-aminocyclitol-6'-acetyltransferase, respectively, were used.

  19. Genetic behavior of the methicillin resistance determinant in Staphylococcus aureus.

    OpenAIRE

    Stewart, G C; Rosenblum, E D

    1980-01-01

    The cotransformation frequency of mecC5 with pur-102 using Staphylococcus aureus C5 deoxyribonucleic acid was found to be approximately 45%. However, in cotransduction studies, there was a 15% cotransduction of purine prototrophy and methicillin sensitivity but, in the reciprocal cross, no purine-prototrophic plus Mecr cotransductants were obtained (frequency less than 0.06%). The data support the hypothesis that the mec determinant resides on an inserted deoxyribonucleic acid sequence in S. ...

  20. Nanoadhesion of Staphylococcus aureus onto Titanium Implant Surfaces

    OpenAIRE

    Aguayo, S.; Donos, N.; Spratt, D.; Bozec, L.

    2015-01-01

    Adhesion of bacteria to dental implant surfaces is the critical initial step in the process of biofilm colonization; however, the specific nanoadhesive interactions occurring during the first contact between bacterial cells and biomaterial substrates remain poorly understood. In this report, we utilize single-cell force spectroscopy to characterize the dynamics of the initial interaction between living Staphylococcus aureus cells and machined titanium surfaces at the nanoscale. Values for max...

  1. Temporal and Stochastic Control of Staphylococcus aureus Biofilm Development

    OpenAIRE

    Moormeier, Derek E.; Bose, Jeffrey L.; Horswill, Alexander R.; Bayles, Kenneth W.

    2014-01-01

    ABSTRACT Biofilm communities contain distinct microniches that result in metabolic heterogeneity and variability in gene expression. Previously, these niches were visualized within Staphylococcus aureus biofilms by observing differential expression of the cid and lrg operons during tower formation. In the present study, we examined early biofilm development and identified two new stages (designated “multiplication” and “exodus”) that were associated with changes in matrix composition and a di...

  2. Molecular Studies on Methicillin-Resistant Staphylococcus aureus

    International Nuclear Information System (INIS)

    The present study of the MecA gene in our clinical isolates has been detected and verified by antibiotic disc diffusion test and nested Polymerase Chain Reaction (PCR). Part of the product of the second PCR was also sequenced. The results indicated 97.7% similarity between the sequences of the mecA gene isolated from an Egyptian Staphylococcus aureus strain and that compared from Staphylococcus aureus strain no. GI46628 cited at the European Molecular Biology Laboratory (EMBL) database under accession number Y00688 in the region from nucleotide 467 to 875. The effect of gamma-radiation on these isolates was observed by plotting the dose survival curves of these isolates and determining their D10 values. Their D10 values were found to be ranged from 0.44 to 0.66 kGy. Antibiotic sensitivity tests were also carried out after exposure of Oxacillin-susceptible isolate to sub -lethal doses of γ-radiation.Results indicated that Staphylococcus aureus isolates which were sensitive to oxacillin discs were found by PCR to harbor the mecA gene in their genomes. Also, exposure of a sensitive isolate to sublethal doses of gamma radiation led to the emergence of a oxacillin-resistant variant which could be a serious problem in case of using sub-lethal doses of radiation for the sterilization of medical products

  3. Novel antibiotics for the treatment of Staphylococcus aureus.

    Science.gov (United States)

    Ohlsen, Knut

    2009-11-01

    Staphylococcus aureus is a leading cause of nosocomial and community-acquired infection associated with significant morbidity and mortality. Antibiotic treatment of infections owing to S. aureus have become increasingly challenging as the pathogen has acquired a broad spectrum of antibiotic resistance mechanisms. In particular, emergence and spread of methicillin-resistant S. aureus (MRSA) progressed to a global health threat. The glycopeptides antibiotics vancomycin and teicoplanin have remained as the drugs of last resort for more than 20 years. Fortunately, in addition to the glycopeptides, several novel antibiotics including linezolid, daptomycin, tigecycline, quinupristin/dalfopristin and ceftobiprole acting against MRSA have been recently introduced into clinical practice broadening therapeutic options. Although the arsenal of antistaphylococcal drugs has filled up in recent years, the rate of MRSA infection continues to be high in most countries. This demands an ongoing search for new antibacterials and lead compounds as well as development of alternative therapies and faster diagnostics to ensure effective anti-staphylococcal therapy in the future. PMID:22112259

  4. Synthetic peptide inhibitors of DNA replication in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Løbner-Olesen, Anders; Kjelstrup, Susanne

    of clinically important pathogens and is essential for bacterial proliferation. The bacterial replication apparatus fulfill the requirements for a good drug target. The replisome of S. aureus consists of 5 different subunits (2, PolC2, 4, δ and δ`) who’s organization depends on multiple protein......-protein interactions. Centrally in the replisome is the -clamp where to multiple proteins binds through a conserved motif. We have identified the protein-protein interactions in the replisome of S. aureus by use of a bacterial two-hybrid system. A reverse bacterial two-hybrid system (R-BTH) based on Pyr......N (), DnaB and DnaX (). Three peptides identified as inhibitors of DnaN have been purified. Two of these peptides inhibited growth as well as DNA replication in S. aureus. The minimal inhibitory concentration (MIC) of the peptides was approximately 50 g/ml. Overexpression of DnaN reduced the inhibitory...

  5. Purification and crystallization of RNase HIII from Staphylococcus aureus

    International Nuclear Information System (INIS)

    The purification, crystallization and preliminary X-ray diffraction analysis of RNase HIII from S. aureus is presented. Crystals that diffracted to 2.6 Å resolution in space group P212121 were only obtained after removal of the hexahistidine tag. As part of collaborative efforts to characterize virulence factors from Staphylococcus aureus, methods for the large-scale recombinant production of RNase HIII from S. aureus subspecies MRSA252 (Sa-RNase HIII) have been developed. RNase HIII-type ribonucleases are poorly characterized members of the RNase H group of endonucleases which hydrolyze RNA from RNA/DNA hybrids and are thought to be involved in DNA replication and repair. They are characterized by N-terminal extensions of unknown function that do not share sequence homology with the N-terminal extensions of bacterial RNases HI and RNases HII. Sa-RNase HIII was crystallized in the orthorhombic space group P212121, with unit-cell parameters a = 48.9, b = 74.2, c = 127.5 Å, and diffracted to 2.6 Å resolution

  6. Staphylococcus aureus Regulatory RNAs as Potential Biomarkers for Bloodstream Infections.

    Science.gov (United States)

    Bordeau, Valérie; Cady, Anne; Revest, Matthieu; Rostan, Octavie; Sassi, Mohamed; Tattevin, Pierre; Donnio, Pierre-Yves; Felden, Brice

    2016-09-01

    Staphylococcus aureus is a commensal bacterium and pathogen. Identifying biomarkers for the transition from colonization to disease caused by this organism would be useful. Several S. aureus small RNAs (sRNAs) regulate virulence. We investigated presence and expression of 8 sRNAs in 83 S. aureus strains from 42 patients with sepsis or septic shock and 41 asymptomatic colonized carriers. Small pathogenicity island sRNAs sprB and sprC were clade specific. Six sRNAs had variable expression not correlated with clinical status. Expression of RNAIII was lower in strains from septic shock patients than in strains from colonized patients. When RNAIII was associated with expression of sprD, colonizing strains could be discriminated from strains in patients with bloodstream infections, including patients with sepsis and septic shock. Isolates associated with colonization might have sRNAs with target expression different from those of disease isolates. Monitoring expression of RNAIII and sprD could help determine severity of bloodstream infections. PMID:27224202

  7. Biochemical characters and antibiotic susceptibility of Staphylococcus aureus isolates

    Institute of Scientific and Technical Information of China (English)

    Subhankari Prasad Chakraborty; Santanu Kar Mahapatra; Somenath Roy

    2011-01-01

    Objective: To observe the biochemical characters and antibiotic susceptibility of isolated Staphylococcus aureus (S. auerus) strains against some conventional and traditional antibiotics.Methods:Bacterial culture was done in Mueller-Hinton broth at 37 ℃. Characters of these strains were determined by traditional biochemical tests such as hydrolysis test of gelatin, urea, galactose, starch and protein, and fermentation of lactose and sucrose. Antibiotic susceptibility were carried out by minimum inhibitory concentration test, minium bactericidal concentration test, disc agar diffusion test and brain heart infusion oxacillin screening agar. Results: From this study, it was observed that 100% S. aureus isolates showed positive results in gelatin, urea and galactose hydrolysis test, 50% isolates were positive in starch hydrolysis test, 35% in protein hydrolysis test, 100% isolates in lactose fermenting test, but no isolate was positive in sucrose fermenting test. Antibiotic susceptibility testing suggested that 20% of isolates were resistant to kanamycin and 46.67% were resistant to oxacillin. Conclusions: These findings show that all these isolates have gelatin, urea, galactose hydrolysis and lactose fermenting activity. 20% of these isolates were resistant to kanamycin and 46.67% were resistant to oxacillin. Thirty post operative pathogenic isolated S. aureus strains were used in this study.

  8. Role of GapC in the pathogenesis of Staphylococcus aureus.

    Science.gov (United States)

    Kerro-Dego, Oudessa; Prysliak, Tracy; Perez-Casal, Jose; Potter, Andrew A

    2012-05-01

    Staphylococcus aureus is recognized worldwide as a major pathogen causing clinical or subclinical intramammary infections in lactating cows, sheep and goats. S. aureus produces a wide arsenal of cell surface and extracellular proteins involved in virulence. Among these are two conserved proteins with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity named glyceraldehyde-3-phosphate dehydrogenase-B (GapB) and -C (GapC). In this study, we used the S. aureus wild type strain RN6390 and its isogenic gapC mutant H330 in in vitro and in vivo studies and determined that the S. aureus GapC protein plays a role on adherence to and internalization into bovine mammary epithelial (MAC-T) cells. In addition, we found that S. aureus H330 did not caused mastitis after an experimental infection of ovine mammary glands. Together, these results show that GapC is important in the pathogenesis of S. aureus mastitis. PMID:22176759

  9. Neonatal colonization with Staphylococcus aureus is not associated with development of atopic dermatitis

    DEFF Research Database (Denmark)

    Skov, L; Halkjaer, L B; Agner, T;

    2009-01-01

    BACKGROUND: Staphylococcus aureus in atopic skin has been associated with exacerbation of eczema. Objectives To investigate a possible association between neonatal colonization with S. aureus and the risk of atopic dermatitis (AD) during the first 3 years of life. MATERIALS AND METHODS: The study...... monitored prospectively. RESULTS: Of the neonates, 5.3% had positive swabs for S. aureus cultured from the vestibulum nasi (51.3%) and/or the perineum (11.3%). Forty-two per cent developed AD, but without association between colonization with S. aureus at 1 month of age and risk of developing AD at 3 years...... of age. There was a 70% concordance for S. aureus carriage between neonates and parents. At 1 year of age 11.3% children had swabs positive for S. aureus. Fourteen per cent of children tested at the 1-year visit developed AD after the visit but before 3 years of age, but again, there was no association...

  10. The growth of Staphylococcus aureus and Escherichia coli in low-direct current electric fields

    Institute of Scientific and Technical Information of China (English)

    Dunya Zituni; Heidi Schu tt-Gerowitt; Marion Kopp; Martin Kro nke; Klaus Addicks; Christian Hoffmann; Martin Hellmich; Franz Faber; Wilhelm Niedermeier

    2014-01-01

    Electrical potentials up to 800 mV can be observed between different metallic dental restorations. These potentials produce fields in the mouth that may interfere with microbial communities. The present study focuses on the impact of different electric field strengths (EFS) on the growth of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) in vitro. Cultures of S. aureus and E. coli in fluid and gel medium were exposed to different EFS. Effects were determined by calculation of viable counts and measurement of inhibition zones. In gel medium, anodic inhibition zones for S. aureus were larger than those for E. coli at all field strength levels. In fluid medium, the maximum decrease in the viable count of S. aureus cells was at 10 V?m21. Field-treated S. aureus cells presented ruptured cell walls and disintegrated cytoplasm. Conclusively, S. aureus is more sensitive to increasing electric field strength than E. coli.

  11. One-year mortality in coagulase-negative Staphylococcus and Staphylococcus aureus infective endocarditis

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Snygg-Martin, Ulrika; Olaison, Lars;

    2009-01-01

    The aim of this study was to investigate in-hospital mortality and 12-month mortality in patients with coagulase-negative Staphylococcus (CoNS) compared to Staphylococcus aureus (S. aureus) infective endocarditis (IE). We used a prospective cohort study of 66 consecutive CoNS and 170 S. aureus IE...... patients, collected at 2 tertiary university hospitals in Copenhagen (Denmark) and at 1 tertiary university hospital in Gothenburg (Sweden). Median (range) C-reactive protein at admission was higher in patients with S. aureus IE (150 mg/l (1-521) vs 94 mg/l (6-303); p...% of patients with S. aureus IE (p =0.05). In conclusion, CoNS IE was associated with a long diagnostic delay and high in-hospital mortality, whereas post-discharge prognosis was better in this group of patients compared to patients with IE due to S. aureus....

  12. Use of mupirocin-chlorhexidine treatment to prevent Staphylococcus aureus surgical-site infections.

    Science.gov (United States)

    Bertrand, X; Slekovec, C; Talon, D

    2010-05-01

    Evaluation of: Bode LGM, Kluytmans JAJW, Wertheim HFL et al.: Preventing surgical-site infections in nasal carriers of Staphylococcus aureus. N. Engl. J. Med. 362, 9-17 (2010). Staphylococcus aureus is the main pathogen responsible for surgical-site infections and nasal carriage is a major risk factor for subsequent infection with this bacteria. Mupirocin is considered to be the topical antibacterial agent of choice for eradication of nasal S. aureus. The paper by Bode et al. provides strong evidence that the combination of a rapid identification of a S. aureus nasal carrier, mupirocin nasal ointment and chlorhexidine gluconate soap, significantly reduces the rate of S. aureus surgical-site infection by nearly 60%. In conclusion, mupirocin nasal ointment use in S. aureus carriers before surgery has numerous advantages with few side effects. PMID:20441543

  13. Pattern differentiation in co-culture biofilms formed by Staphylococcus aureus and Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Yang, Liang; Liu, Yang; Markussen, Trine;

    2011-01-01

    -culture biofilms. By growing co-culture biofilms of S. aureus with P. aeruginosa mutants in a flow-chamber system and observing them using confocal laser scanning microscopy, we show that wild-type P. aeruginosa PAO1 facilitates S. aureus microcolony formation. In contrast, P. aeruginosa mucA and rpoN mutants do...... not facilitate S. aureus microcolony formation and tend to outcompete S. aureus in co-culture biofilms. Further investigations reveal that extracellular DNA (eDNA) plays an important role in S. aureus microcolony formation and that P. aeruginosa type IV pili are required for this process, probably through...... their ability to bind to eDNA. Furthermore, P. aeruginosa is able to protect S. aureus against Dictyostelium discoideum phagocytosis in co-culture biofilms....

  14. The dynamics of Staphylococcus aureus intramammary infection in nine Danish dairy herds

    DEFF Research Database (Denmark)

    Larsen, H. D.; Sloth, K. H.; Elsberg, C.;

    2000-01-01

    The aim of the present study was to examine the diversity of Staphylococcus aureus isolates from bovine intramammary infections (IMI) in nine dairy herds, and compare these with isolates from other sites on the cows by phage- and ribotyping. Whether colonisation of milkers with S. aureus could...... be a source of infection for bovine IMI was investigated. In addition, 100 epidemiologically unrelated S. aureus isolates from asymptomatic human carriers were also phage- and ribotyped to compare the human and bovine reservoir of S. aureus in Denmark. A total of 625 S. aureus isolates from bovine IMI, bovine......, there was a close correspondence between ribo- and phage types of S. aureus isolated from bovine intramammmary infections and skin lesions. Isolates from milking personnel, however, were not identical to any of the predominant intramammary strains. Furthermore, several of the isolates from milking personnel showed...

  15. Antimicrobial susceptibility of Staphylococcus aureus and characterization of methicillin-resistant Staphylococcus aureus isolated from bovine mastitis in Korea.

    Science.gov (United States)

    Nam, Hyang-Mi; Lee, Ae-Li; Jung, Suk-Chan; Kim, Mal-Nam; Jang, Geum-Chan; Wee, Sung-Hwan; Lim, Suk-Kyung

    2011-02-01

    A total of 402 Staphylococcus aureus isolates from bovine mastitis milk collected during 2003-2009 in Korea were tested for susceptibility to 20 antimicrobial agents. All S. aureus isolates were susceptible to 11 of 20 antimicrobials tested; no resistance was observed against pirlimycin, telithromycin, novobiocin, penicillin/novobiocin, quinupristin/dalfopristin, clindamycin, rifampin, ciprofloxacin, trimethprim/sulfamethoxazol, vancomycin, and linezolid. Over 66% of the S. aureus isolates were resistant to penicillin. Resistance was also seen for gentamicin (11.9%), erythromycin (7.7%), methicillin (oxacillin and cefoxitin, 6.2%), and tetracycline (4.2%). No noticeable change was observed in penicillin, gentamicin, and erythromycin resistance over the 7-year period. Tetracycline resistance appeared to decrease consistently, whereas methicillin resistance was observed from 2005. About 2.7% (11/402) were resistant to three or more antimicrobials. Genotyping of the 17 methicillin-resistant S. aureus (MRSA) isolated from each cow revealed two staphylococcal cassette chromosome mec (SCCmec) types (IV and IVa), three spa types (t286, t324, and untypable), and two sequence types (ST1 and ST72). Eleven of 17 (64.7%) MRSA strains belonged to SCCmec IVa-t324-ST72. The rest of strains belonged to SCCmec IVa-t286-ST1 (n = 3) and SCCmec IV-untypable-ST72 (n = 3). None of the MRSA carried the Panton-Valentine leukocidin gene. These characteristics are the same as those found in community-acquired (CA) MRSA strains prevalent in humans in Korea. Three pulsed-field gel electrophoresis types (A-C) were observed among the 17 MRSA strains examined, and 14 strains belonged to the same pulsed-field gel electrophoresis pattern regardless of their geographical origin and year of isolation. The results of this study provide evidence of CA-MRSA infection in dairy cattle for the first time in Korea. PMID:21034263

  16. Surgimiento y diseminación de Staphylococcus aureus meticilinorresistente Staphylococcus aureus methicillin-resistant: emergence and dissemination

    OpenAIRE

    Maria Elena Velázquez-Meza

    2005-01-01

    Las infecciones nosocomiales ocasionadas por cepas de Staphylococcus aureus meticilinorresistentes (SAMR) son un problema de salud importante en todo el mundo. Este microorganismo produce una gran variedad de infecciones incluyendo osteomielitis, endocarditis invasora, artritis séptica y septicemia. La multirresistencia es un factor que influye en la persistencia de los SAMR dentro del ámbito hospitalario. La introducción de técnicas de tipificación molecular dentro de las investigaciones epi...

  17. VARIABILITY OF PHENOTYPIC, PROTEOMIC AND TRANSCRIPTOMIC EXPRESSION OF STAPHYLOCOCCUS AUREUS SURFACE ADHESINS

    OpenAIRE

    Ythier M.

    2012-01-01

    Staphylococcus aureus is a highly successful pathogen responsible of a wide variety of diseases, from minor skin infection to life-threatening sepsis or infective endocarditis, as well as food poisoning and toxic shock syndrome. This heterogeneity of infections and the ability of S. aureus to develop antibiotic-resistance to virtually any available drugs reflect its extraordinary capacity to adapt and survive in a great variety of environments. The pathogenesis of S. aureus infection involves...

  18. Glycolytic Dependency of High-Level Nitric Oxide Resistance and Virulence in Staphylococcus aureus

    OpenAIRE

    Vitko, Nicholas P.; Spahich, Nicole A.; Richardson, Anthony R.

    2015-01-01

    ABSTRACT Staphylococcus aureus is a prolific human pathogen capable of causing severe invasive disease with a myriad of presentations. The ability of S. aureus to cause infection is strongly linked with its capacity to overcome the effects of innate immunity, whether by directly killing immune cells or expressing factors that diminish the impact of immune effectors. One such scenario is the induction of lactic acid fermentation by S. aureus in response to host nitric oxide (NO·). This ferment...

  19. Exposure and risk assessment of Staphylococcus aureus in food chain in Slovakia

    OpenAIRE

    Ľubomír Valík; Alžbeta Medveďová

    2013-01-01

    Foods can been contaminated by S. aureus usually as a result of unhygienic behaviour of staff or improper conducted technological procedures. Compared to saprophytic bacteria, S. aureus does not possess significant competitive properties; however its epidemiological potential consists in multiplication to density higher than 106 cfu/g and formation of heat-resistant enterotoxins by which it causes food poisoning. Based on the data in 2001, the risk was characterized as follows: S. aureus is ...

  20. Subinhibitory concentrations of perilla oil affect the expression of secreted virulence factor genes in Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Jiazhang Qiu

    Full Text Available BACKGROUND: The pathogenicity of staphylococcus aureus is dependent largely upon its ability to secrete a number of virulence factors, therefore, anti-virulence strategy to combat S. aureus-mediated infections is now gaining great interest. It is widely recognized that some plant essential oils could affect the production of staphylococcal exotoxins when used at subinhibitory concentrations. Perilla [Perilla frutescens (L. Britton], a natural medicine found in eastern Asia, is primarily used as both a medicinal and culinary herb. Its essential oil (perilla oil has been previously demonstrated to be active against S. aureus. However, there are no data on the influence of perilla oil on the production of S. aureus exotoxins. METHODOLOGY/PRINCIPAL FINDINGS: A broth microdilution method was used to determine the minimum inhibitory concentrations (MICs of perilla oil against S. aureus strains. Hemolysis, tumour necrosis factor (TNF release, Western blot, and real-time RT-PCR assays were performed to evaluate the effects of subinhibitory concentrations of perilla oil on exotoxins production in S. aureus. The data presented here show that perilla oil dose-dependently decreased the production of α-toxin, enterotoxins A and B (the major staphylococcal enterotoxins, and toxic shock syndrome toxin 1 (TSST-1 in both methicillin-sensitive S. aureus (MSSA and methicillin-resistant S. aureus (MRSA. CONCLUSIONS/SIGNIFICANCE: The production of α-toxin, SEA, SEB, and TSST-1 in S. aureus was decreased by perilla oil. These data suggest that perilla oil may be useful for the treatment of S. aureus infections when used in combination with β-lactam antibiotics, which can increase exotoxins production by S. aureus at subinhibitory concentrations. Furthermore, perilla oil could be rationally applied in food systems as a novel food preservative both to inhibit the growth of S. aureus and to repress the production of exotoxins, particularly staphylococcal enterotoxins.

  1. Methicillin-resistant Staphylococcus aureus colonization among pediatric health care workers from different outpatient settings

    OpenAIRE

    Immergluck, Lilly Cheng; Satola, Sarah W.; Jain, Shabnam; Courtney, McCracken; Watson, J. Reneé; Chan, Trisha; Traci, Leong; Gottlieb, Edward; Jerris, Robert C

    2013-01-01

    Staphylococcus aureus colonization rates in pediatric health care workers from different types of outpatient settings were determined from December 2008 through May 2010. Colonization rates for Staphylococcus aureus and, specifically, methicillin-resistant Staphylococcus aureus (MRSA) rates were similar to the rates that have been reported for the general population. The predominant MRSA pulsed-field gel electrophoresis type associated with colonization in these health care workers is not MRS...

  2. IsdB-dependent Hemoglobin Binding Is Required for Acquisition of Heme by Staphylococcus aureus

    OpenAIRE

    Pishchany, Gleb; Sheldon, Jessica R.; Dickson, Claire F.; Alam, Md Tauqeer; Read, Timothy D.; Gell, David A; Heinrichs, David E.; Skaar, Eric P.

    2013-01-01

    Staphylococcus aureus is a Gram-positive pathogen responsible for tremendous morbidity and mortality. As with most bacteria, S. aureus requires iron to cause disease, and it can acquire iron from host hemoglobin. The current model for staphylococcal hemoglobin-iron acquisition proposes that S. aureus binds hemoglobin through the surface-exposed hemoglobin receptor IsdB. IsdB removes heme from bound hemoglobin and transfers this cofactor to other proteins of the Isd system, which import and de...

  3. High Level Expression and Purification of Atl, the Major Autolytic Protein of Staphylococcus aureus

    OpenAIRE

    Singh, Vineet K.

    2014-01-01

    Staphylococcus aureus is a major human and animal pathogen. Autolysins regulate the growth, turnover, cell lysis, biofilm formation, and the pathogenicity of S. aureus. Atl is the major autolysin in S. aureus. The biochemical and structural studies of staphylococcal Atl have been limited due to difficulty in cloning, high level overexpression, and purification of this protein. This study describes successful cloning, high level over-expression, and purification of two forms of fully functiona...

  4. Identification of Staphylococcus aureus Colony-Spreading Stimulatory Factors from Mammalian Serum

    OpenAIRE

    Yosuke Omae; Kazuhisa Sekimizu; Chikara Kaito

    2014-01-01

    Staphylococcus aureus forms giant colonies on soft-agar surfaces, which is called colony-spreading. In the present study, we searched for host factors that influence S. aureus colony-spreading activity. The addition of calf serum, porcine serum, or silkworm hemolymph to soft-agar medium stimulated S. aureus colony-spreading activity. Gel filtration column chromatography of calf serum produced a high molecular weight fraction and a low molecular weight fraction, both of which exhibited colony-...

  5. Mechanism of hetero-erythromycin resistant Staphylococcus aureus and a comparison of detection methods

    Institute of Scientific and Technical Information of China (English)

    陈东科

    2014-01-01

    Objective To explore the phenotypes and genotypes of Staphylococcus aureus(S.aureus)hetero-resistant to erythromycin and clindamycin and compare their detection methods so as to report results accurately to guide clinical rational use of antibiotics.Methods D test was used to detect the phenotypes of S.aureus hetero-resistant to erythromycin.And then the results of two methods(automated instrument and disk diffusion)were analyzed.All strains were continuously passaged for 50 generations to

  6. Evaluation of high-dose daptomycin for therapy of experimental Staphylococcus aureus foreign body infection

    OpenAIRE

    Lew Daniel P; Bento Manuela; Schaad Heinz J; Vaudaux Pierre

    2006-01-01

    Abstract Background Daptomycin is a novel cyclic lipopeptide whose bactericidal activity is not affected by current antibiotic resistance mechanisms displayed by S. aureus clinical isolates. This study reports the therapeutic activity of high-dose daptomycin compared to standard regimens of oxacillin and vancomycin in a difficult-to-treat, rat tissue cage model of experimental therapy of chronic S. aureus foreign body infection. Methods The methicillin-susceptible S. aureus (MSSA) strain I20 ...

  7. High Genetic Diversity among Community-Associated Staphylococcus aureus in Europe: Results from a Multicenter Study

    OpenAIRE

    Rolo, Joana; Miragaia, Maria; Turlej-Rogacka, Agata; Empel, Joanna; Bouchami, Ons; Faria, Nuno A.; Tavares, Ana; Hryniewicz, Waleria; Fluit, Ad C.; de Lencastre, Hermínia

    2012-01-01

    Background Several studies have addressed the epidemiology of community-associated Staphylococcus aureus (CA-SA) in Europe; nonetheless, a comprehensive perspective remains unclear. In this study, we aimed to describe the population structure of CA-SA and to shed light on the origin of methicillin-resistant S. aureus (MRSA) in this continent. Methods and Findings A total of 568 colonization and infection isolates, comprising both MRSA and methicillin-susceptible S. aureus (MSSA), were recover...

  8. Methicillin-Resistant Staphylococcus aureus Associated with Animals and Its Relevance to Human Health

    OpenAIRE

    AnnalisaPantosti

    2012-01-01

    Staphylococcus aureus is a typical human pathogen. Some animal S. aureus lineages have derived from human strains following profound genetic adaptation determining a change in host specificity. Due to the close relationship of animals with the environmental microbioma and resistoma, animal staphylococcal strains also represent a source of resistance determinants. Methicillin-resistant S. aureus (MRSA) emerged fifty years ago as a nosocomial pathogen but in the last decade it has also become...

  9. Staphylococcus aureus infections in children in an Iranian referral pediatric Hospital

    OpenAIRE

    SABOUNI, F.; RANJBARI, R.; B Pourakbari; Mahmoudi, S; TEYMURI, M.; TAGHI HAGHI ASHTIANI, M.; MOVAHEDI, Z.; S Mamishi

    2013-01-01

    Summary Introduction. Staphylococcus aureus is associated with various infections ranging from skin and soft tissues such as surgical site infections and abscesses to lower respiratory tracts and bloodstream. The aim of this study was to evaluate underlying condition of patients with S. aureus infections in an Iranian referral pediatric Hospital. Material and methods. Information was extracted retrospectively from the medical records of patients who were diagnosed with S. aureus infections. D...

  10. Differential Expression and Roles of Staphylococcus aureus Virulence Determinants during Colonization and Disease

    OpenAIRE

    Jenkins, Amy; Diep, Binh An; Mai, Thuy T.; Vo, Nhung H.; Warrener, Paul; Suzich, Joann; Stover, C. Kendall; Sellman, Bret R.

    2015-01-01

    ABSTRACT Staphylococcus aureus is a Gram-positive, commensal bacterium known to asymptomatically colonize the human skin, nares, and gastrointestinal tract. Colonized individuals are at increased risk for developing S. aureus infections, which range from mild skin and soft tissue infections to more severe diseases, such as endocarditis, bacteremia, sepsis, and osteomyelitis. Different virulence factors are required for S. aureus to infect different body sites. In this study, virulence gene ex...

  11. Polymorphism in spa gene of Staphylococcus aureus from bovine subclinical mastitis

    OpenAIRE

    Taruna Bhati; Prerna Nathawat; Sandeep Kumar Sharma; Rahul Yadav; Jyoti Bishnoi; Anil Kumar Kataria

    2016-01-01

    Aim: The virulence-associated protein-A of Staphylococcus aureus, encoded by spa gene shows a variation in length in different strains. In this study, the spa gene variation in S. aureus strains was studied which were isolated from subclinical cases of bovine mastitis. Materials and Methods: About 38 isolates of S. aureus were recovered from Holstein–Friesian (HF) crossbred (n=16) and Rathi cattle (n=22) with subclinical mastitis as per standard procedures, and these isolates were subjecte...

  12. Polymorphism in spa gene of Staphylococcus aureus from bovine subclinical mastitis

    OpenAIRE

    Bhati, Taruna; Nathawat, Prerna; Sharma, Sandeep Kumar; Yadav, Rahul; Bishnoi, Jyoti; Kataria, Anil Kumar

    2016-01-01

    Aim: The virulence-associated protein-A of Staphylococcus aureus, encoded by spa gene shows a variation in length in different strains. In this study, the spa gene variation in S. aureus strains was studied which were isolated from subclinical cases of bovine mastitis. Materials and Methods: About 38 isolatesof S. aureus were recovered from Holstein–Friesian (HF) crossbred (n=16) and Rathi cattle (n=22) with subclinical mastitis as per standard procedures, and these isolates were subjected to...

  13. Application of molecular techniques in the study of Staphylococcus aureus clonal evolution - A Review

    Directory of Open Access Journals (Sweden)

    Adriana Marcos Vivoni

    2005-11-01

    Full Text Available Staphylococcus aureus is an important agent of healthcare-associated and community-acquired infections. A major characteristic of this microorganism is the ability to develop resistance to antimicrobial agents. Several molecular techniques have been applied for the characterization of S. aureus in epidemiological studies. In the present review, we discuss the application of molecular techniques for typing S. aureus strains and describe the nomenclature and evolution of epidemic clones of this important pathogen.

  14. Clonal diversity of Staphylococcus aureus originating from the small ruminants goats and sheep

    DEFF Research Database (Denmark)

    Concepción Porrero, M.; Hasman, Henrik; Vela, Ana I.;

    2012-01-01

    Staphylococcus aureus is an important pathogen in humans and many animal species. The prevalence of different clonal types in animal species remains largely unknown. We analyzed 267 S. aureus from intramammary infections in goats (47) and sheep (220) by spa typing, multi-locus sequence typing (MLST...... was detected to cefoxitin, quinupristin-dalfopristin, rifampicin and vancomycin. This study suggests that ST522 is the most common S. aureus clone associated with small ruminants followed by CC133....

  15. Current status of Staphylococcus aureus infection in a central teaching hospital in Shanghai, China

    OpenAIRE

    Li, Tianming; Song, Yan; Zhu, Yuanjun; Du, Xin; Li, Min

    2013-01-01

    Background To control the spread of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals, infection control measures such as hand hygiene practices were introduced into the teaching hospitals in Shanghai, China, in 2008. Currently, there is limited information characterizing the latest hospital-acquired S. aureus infections in this area. Therefore, we sought to determine the prevalence, molecular characteristics, and genotype-phenotype correlation of hospital-acquired S. aureus inf...

  16. Attenuated Virulence and Biofilm Formation in Staphylococcus aureus following Sublethal Exposure to Triclosan

    OpenAIRE

    Latimer, Joe; Forbes, Sarah; McBain, Andrew J.

    2012-01-01

    Subeffective exposure of Staphylococcus aureus to the biocide triclosan can reportedly induce a small-colony variant (SCV) phenotype. S. aureus SCVs are characterized by low growth rates, reduced pigmentation, and lowered antimicrobial susceptibility. While they may exhibit enhanced intracellular survival, there are conflicting reports regarding their pathogenicity. The current study reports the characteristics of an SCV-like strain of S. aureus created by repeated passage on sublethal triclo...

  17. Novel Chromosomally Encoded Multidrug Efflux Transporter MdeA in Staphylococcus aureus

    OpenAIRE

    Huang, Jianzhong; O'Toole, Paul W.; Shen, Wei; Amrine-Madsen, Heather; Jiang, Xinhe; Lobo, Neethan; Palmer, Leslie M.; Voelker, LeRoy; Fan, Frank; Gwynn, Michael N.; McDevitt, Damien

    2004-01-01

    Antibiotic efflux is an important mechanism of resistance in pathogenic bacteria. Here we describe the identification and characterization of a novel chromosomally encoded multidrug resistance efflux protein in Staphylococcus aureus, MdeA (multidrug efflux A). MdeA was identified from screening an S. aureus open reading frame expression library for resistance to antibiotic compounds. When overexpressed, MdeA confers resistance on S. aureus to a range of quaternary ammonium compounds and antib...

  18. Staphylococcus aureus seroproteomes discriminate ruminant isolates causing mild or severe mastitis

    OpenAIRE

    Le Maréchal Caroline; Jardin Julien; Jan Gwenaël; Even Sergine; Pulido Coralie; Guibert Jean-Michel; Hernandez David; François Patrice; Schrenzel Jacques; Demon Dieter; Meyer Evelyne; Berkova Nadia; Thiéry Richard; Vautor Eric; Le Loir Yves

    2011-01-01

    Abstract Staphylococcus aureus is a major cause of mastitis in ruminants. In ewe mastitis, symptoms range from subclinical to gangrenous mastitis. S. aureus factors or host-factors contributing to the different outcomes are not completely elucidated. In this study, experimental mastitis was induced on primiparous ewes using two S. aureus strains, isolated from gangrenous (strain O11) or subclinical (strain O46) mastitis. Strains induced drastically distinct clinical symptoms when tested in ew...

  19. A rare case of acute epiglottitis due to Staphylococcus aureus in an adult

    Directory of Open Access Journals (Sweden)

    Clare Harris

    2012-01-01

    Full Text Available Epiglottitis has been mainly associated with childhood infection with Haemophilis influenzae type B but cases of adult epiglottitis are increasing. We report here a case of adult epiglottitis and present evidence that it was caused by S. aureus. A 48-year old patient with clinical symptoms of epiglottitis grew Staphylococcus aureus in pure culture from an epiglottal swab. Staphylococcus aureus should be considered as a potential pathogen in adult epiglottitis.

  20. Development and Evaluation of a Chromogenic Agar Medium for Methicillin-Resistant Staphylococcus aureus

    OpenAIRE

    Perry, John D.; Davies, Amie; Butterworth, Lynne A.; Hopley, Andrew L. J.; Nicholson, Audrey; Gould, F. Kate

    2004-01-01

    We describe here the development and evaluation of MRSA ID, a new chromogenic agar medium for the specific isolation and identification of methicillin-resistant Staphylococcus aureus (MRSA). We used S. aureus ID (bioMérieux, La Balme Les Grottes, France) and supplemented it with various antimicrobials, including cefoxitin, ciprofloxacin, oxacillin, and methicillin. Cefoxitin proved to be superior to the other antimicrobials for the selection of MRSA from other strains of S. aureus. MRSA ID (c...

  1. Inducible clindamycin resistance in Staphylococcus aureus isolated from nursing and pharmacy students

    Directory of Open Access Journals (Sweden)

    Renushri

    2011-01-01

    Full Text Available Aims: Emergence of resistant isolates of Staphylococcus aureus (S. aureus has resulted in failure of clindamycin therapy. The prevalence of inducible clindamycin resistance in S. aureus isolated from nursing students and pharmacy students (representing carriers exposed and not exposed to hospital environment respectively was evaluated. Materials and Methods: Nasal, throat, and palmar swabs were collected from 119 nursing students and 100 pharmacy students. S. aureus was identified and antibiogram obtained by Clinical and Laboratory Standards Institute guidelines. Inducible clindamycin resistance was detected by the D-test. Results: 36 and 34 individuals in the exposed and non-exposed groups respectively were carriers of S. aureus. 16.7% and 5.9% isolates showed inducible clindamycin resistance in exposed and non-exposed groups, respectively. The percentage of inducible clindamycin resistance was higher among methicillin-resistant S. aureus (MRSA (27.8% compared to methicillin-sensitive S. aureus (5.8%. Conclusion: S. aureus isolates resistant to β-lactams can also show inducible clindamycin resistance. Exposure to hospital environment was not found to be a risk factor for carriage of S. aureus with MLSBi phenotype.

  2. Characterization of Haemolysin of Staphylococcus aureus Isolated from Food of Animal Origin

    Directory of Open Access Journals (Sweden)

    Dwi Ariyanti

    2015-11-01

    Full Text Available Staphylococcus aureus is an important pathogen bacteria causing food poisoning and various infection in animals and humans. Haemolysin is one of the virulence factors of Staphylococcus aureus. The aims of the research were to characterize haemolysins of Staphylococcus aureus isolated from various food of animal origin, phenotypic- and genotypically. In the present study, eleven Staphylococcus aureus isolated from various food of animal origins from traditional markets and supermarkets in Yogyakarta, Sidoarjo, Jakarta, and Bandung were characterized for haemolysin, pheno- and genotypically. Characterization of haemolysin phenotypically based on haemolysis pattern of Staphylococcus aureus on sheep blood agar plate. Genes encoding hemolysin were amplified with specific primers by using polymerase chain reaction (PCR technique. The results of the studies showed that Staphylococcus aureus on sheep blood agar plates revealed an alpha haemolysis pattern (18,18%, beta haemolysis (27,27% and gamma haemolysis (54,55%. Based on amplification of the gene encoding haemolysin of Staphylococcus aureus with specific primers showed hla genes (81,81%, and hla combined with hlb genes (18,18%. The amplification of gene hla and hlb had a single amplicon with a size of approximately 534 bp and 833 bp, respectively. The haemolysin characteristics of Staphylococcus aureus from various food of animal origin could be used as important information to control staphylococcal food poisoning.Keywords : Staphylococcus aureus, haemolysin, PCR, food of animal origins

  3. Characterization of Methicillin-Resistant Staphylococcus aureus Isolates from Patients with Persistent or Recurrent Bacteremia

    Directory of Open Access Journals (Sweden)

    Henry Wong

    2014-01-01

    Full Text Available BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA bloodstream infections (BSI are associated with considerable morbidity and mortality, especially with persistent (PB or recurrent bacteremia (RB.

  4. spa type distribution in Staphylococcus aureus originating from pigs, cattle and poultry

    DEFF Research Database (Denmark)

    Hasman, Henrik; Moodley, A.; Guardabassi, L.;

    2010-01-01

    Methicillin-resistant S. aureus (MRSA) of clonal complex 398 (CC398) is emerging globally among production animals such as cattle, pigs and poultry as well as among humans. However, little is known about the prevalence of CC398 among methicillin sensitive S. aureus (MSSA) or the relative clonal...... distribution of S. aureus isolated from these three animal reservoirs. To study this, we have analyzed a random sample of S. aureus consisting of 296 epidemiologically unrelated isolates from infections and colonisation of pigs, cattle and poultry. These were examined and compared by spa and multi...

  5. Dual-recognition detection of Staphylococcus aureus using vancomycin-functionalized magnetic beads as concentration carriers.

    Science.gov (United States)

    Yang, Shijia; Ouyang, Hui; Su, Xiaoxiao; Gao, Hongfei; Kong, Weijun; Wang, Mengyao; Shu, Qi; Fu, Zhifeng

    2016-04-15

    Vancomycin, which has a strong antibacterial effect to Gram-positive bacteria, was adopted as one molecular recognition agent for bacterial detection. Magnetic beads (MBs) were functionalized with this antibiotic to effectively concentrate Staphylococcus aureus (S. aureus). In addition, alkaline phosphatase (ALP)-tagged rabbit immunoglobulin G (ALP-IgG) was used as the second recognition agent to improve the specificity based on the binding between the Fc region of rabbit IgG and protein A in the cell wall of S. aureus. MBs-concentrated sandwich complex of vancomycin/S. aureus/ALP-IgG was formed with a one-step incubation protocol. Then ALP chemiluminescent reaction was triggered by injecting substrate solution to quantitate S. aureus. Based on the sandwich molecular recognition mechanism and MBs concentration, an ultrasensitive, specific and rapid method was developed for S. aureus detection. The linear range for S. aureus detection was 12-1.2 × 10(6)CFU mL(-1), with a very low detection limit of 3.3 CFU mL(-1). The whole detection process could be completed in 75 min. Other Gram-positive bacteria and Gram-negative bacteria, including Escherichia coli, Salmonella, Pseudomonas aeruginosa, Micrococcus luteus, Bacillus cereus and Bacillus subtilis, showed negligible interference to S. aureus detection. This method was successfully used to quantitate S. aureus in lake water, milk, human urine and human saliva with acceptable recoveries ranging from 70.0% to 116.7%. PMID:26606309

  6. Aktivitas Imunomodulator Ekstrak Buah Mengkudu pada Mencit yang Diinfeksi Staphylococcus aureus (IMMUNOMODULATORS ACTIVITY OF NONI (MORINDA CITRIFOLIA L.) FRUIT EXTRACT IN MICE INFECTED WITH STAPHYLOCOCCUS AUREUS)

    OpenAIRE

    Zumrotul Mufidah; Muhaimin Rifa’i; Sri Rahayu

    2013-01-01

    This study aim was to determine the immunomodulatory activity of noni (Morinda citrifolia L.) fruitextract in mice infected with Staphylococcus aureus. Mice were divided into two group :  non-infected  andinfected. Non Infected group was without S. aureus infection whereas the infected group was infected withS. aureus. Group contain control, dose 1 (25 mg/kg BW), dose 2 (100 mg/kg BW), and dose 3 (300 mg/kg BW).Oral treatment carried out for 20 days in every morning and each sample was inject...

  7. Sepse por Staphylococus aureus resistente à meticilina adquirida na comunidade no sul do Brasil Sepsis due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil

    OpenAIRE

    Luciane Cristina Gelatti; Tereza Sukiennik; Ana Paula Becker; Fernanda Matsiko Inoue; Mirian Silva do Carmo; Fernanda Marques da Silva Castrucci; Antônio Carlos Campos Pignatari; Luis Carlos Ribeiro; Renan Rangel Bonamigo; Pedro Alves d?Azevedo

    2009-01-01

    Staphylococcus aureus resistente à meticilina foi inicialmente descrito como um típico microrganismo adquirido em infecções nosocomiais. No entanto, nos últimos anos Staphylococcus aureus resistente à meticilina adquirido na comunidade é causa de infecções de pele e tecidos moles, mas infecções graves como pneumonia e sepse podem ocorrer. Este relato descreve um caso de sepse em criança, complicado com pneumonia secundária a lesão em partes moles por Staphylococcus aureus resistente à meticil...

  8. Occurrence and antimicrobial resistance of Staphylococcus aureus in bulk tank milk and milk filters

    Directory of Open Access Journals (Sweden)

    Kateřina Bogdanovičová

    2014-02-01

    Full Text Available This work is focused on the monitoring of Staphylococcus aureus prevalence in raw milk and milk filters, its antibiotic resistance and detection of methicillin resistant Staphylococcus aureus (MRSA. Samples of raw cow´s milk and milk filters were collected in the period from 2012 till 2014, from 50 dairy farms in the Czech Republic. The total of 261 samples (164 samples of raw milk and 97 milk filters were cultivated on Baird-Parker agar. Both the typical and atypical colonies were examined by plasmacoagulase test and PCR method was used for detection of species specific fragment SA442 and mecA gene. Standard disk diffusion method was used to determinate resistance to antimicrobial agents. The bacterium Staphylococcus aureus was detected on 25 farms (50%. The antimicrobial resistance showed differences between the farms. Total of 58 samples were positive for Staphylococcus aureus, of which were 37 (14.2% isolated from raw milk samples and 21 (8.1% from milk filters. From these samples we isolated 62 Staphylococcus aureus strains, 41 isolates bacteria S. aureus from raw milk (66.1% and 21 isolates S. aureus from milk filters (33.9%. The presence of antibiotic resistance in Staphylococcus aureus isolates was low, most of them were resistant to amoxicilin. According to the results obtained by the PCR method for the methicillin - resistant S. aureus (MRSA, the mecA gene was present in 6 strains (9.7%, 4 isolates obtained from milk samples (6.5% and 2 isolates from milk filters (3.2%.  These isolates can be considered as a possible source of resistance genes, which can be spread through the food chain. Nowadays, a globally unfavourable increasing trend of prevalence of methicillin resistant staphylococci strains especially Staphylococcus aureus is being observed worldwide. The improper hygiene and poor farm management practices contributed to the presence of S. aureus in the milk. This may have contributed to the high level of S. aureus isolated

  9. Staphylococcus aureus α-Toxin: Nearly a Century of Intrigue

    Directory of Open Access Journals (Sweden)

    Bryan J. Berube

    2013-06-01

    Full Text Available Staphylococcus aureus secretes a number of host-injurious toxins, among the most prominent of which is the small β-barrel pore-forming toxin α-hemolysin. Initially named based on its properties as a red blood cell lytic toxin, early studies suggested a far greater complexity of α-hemolysin action as nucleated cells also exhibited distinct responses to intoxication. The hemolysin, most aptly referred to as α-toxin based on its broad range of cellular specificity, has long been recognized as an important cause of injury in the context of both skin necrosis and lethal infection. The recent identification of ADAM10 as a cellular receptor for α-toxin has provided keen insight on the biology of toxin action during disease pathogenesis, demonstrating the molecular mechanisms by which the toxin causes tissue barrier disruption at host interfaces lined by epithelial or endothelial cells. This review highlights both the historical studies that laid the groundwork for nearly a century of research on α-toxin and key findings on the structural and functional biology of the toxin, in addition to discussing emerging observations that have significantly expanded our understanding of this toxin in S. aureus disease. The identification of ADAM10 as a proteinaceous receptor for the toxin not only provides a greater appreciation of truths uncovered by many historic studies, but now affords the opportunity to more extensively probe and understand the role of α-toxin in modulation of the complex interaction of S. aureus with its human host.

  10. Repurposing salicylanilide anthelmintic drugs to combat drug resistant Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Rajmohan Rajamuthiah

    Full Text Available Staphylococcus aureus is a Gram-positive bacterium that has become the leading cause of hospital acquired infections in the US. Repurposing Food and Drug Administration (FDA approved drugs for antimicrobial therapy involves lower risks and costs compared to de novo development of novel antimicrobial agents. In this study, we examined the antimicrobial properties of two commercially available anthelmintic drugs. The FDA approved drug niclosamide and the veterinary drug oxyclozanide displayed strong in vivo and in vitro activity against methicillin resistant S. aureus (minimum inhibitory concentration (MIC: 0.125 and 0.5 μg/ml respectively; minimum effective concentration: ≤ 0.78 μg/ml for both drugs. The two drugs were also effective against another Gram-positive bacteria Enterococcus faecium (MIC 0.25 and 2 μg/ml respectively, but not against the Gram-negative species Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter aerogenes. The in vitro antimicrobial activity of niclosamide and oxyclozanide were determined against methicillin, vancomycin, linezolid or daptomycin resistant S. aureus clinical isolates, with MICs at 0.0625-0.5 and 0.125-2 μg/ml for niclosamide and oxyclozanide respectively. A time-kill study demonstrated that niclosamide is bacteriostatic, whereas oxyclozanide is bactericidal. Interestingly, oxyclozanide permeabilized the bacterial membrane but neither of the anthelmintic drugs exhibited demonstrable toxicity to sheep erythrocytes. Oxyclozanide was non-toxic to HepG2 human liver carcinoma cells within the range of its in vitro MICs but niclosamide displayed toxicity even at low concentrations. These data show that the salicylanilide anthelmintic drugs niclosamide and oxyclozanide are suitable candidates for mechanism of action studies and further clinical evaluation for treatment of staphylococcal infections.

  11. Healthcare-Associated Methicillin-Resistant Staphylococcus aureus

    Science.gov (United States)

    Kumari, Jyoti; Shenoy, Shalini M.; Baliga, Shrikala; Chakrapani, M.; Bhat, Gopalkrishna K.

    2016-01-01

    Objectives: Healthcare-associated methicillin-resistant Staphylococcus aureus (MRSA) is a common pathogen worldwide and its multidrug resistance is a major concern. This study aimed to determine the clinical characteristics and antibiotic susceptibility profile of healthcare-associated MRSA with emphasis on resistance to macrolide-lincosamide-streptogramin B (MLSB) phenotypes and vancomycin. Methods: This cross-sectional study was carried out between February 2014 and February 2015 across four tertiary care hospitals in Mangalore, South India. Healthcare-associated infections among 291 inpatients at these hospitals were identified according to the Centers for Disease Control and Prevention guidelines. Clinical specimens were collected based on infection type. S. aureus and MRSA isolates were identified and antibiotic susceptibility tests performed using the Kirby-Bauer disk diffusion method. The minimum inhibitory concentration of vancomycin was determined using the Agar dilution method and inducible clindamycin resistance was detected with a double-disk diffusion test (D-test). Results: Out of 291 healthcare-associated S. aureus cases, 88 were MRSA (30.2%). Of these, 54.6% were skin and soft tissue infections. All of the isolates were susceptible to teicoplanin and linezolid. Four MRSA isolates exhibited intermediate resistance to vancomycin (4.6%). Of the MRSA strains, 10 (11.4%) were constitutive MLSB phenotypes, 31 (35.2%) were inducible MLSB phenotypes and 14 (15.9%) were macrolide-streptogramin B phenotypes. Conclusion: Healthcare-associated MRSA multidrug resistance was alarmingly high. In routine antibiotic susceptibility testing, a D-test should always be performed if an isolate is resistant to erythromycin but susceptible to clindamycin. Determination of the minimum inhibitory concentration of vancomycin is necessary when treating patients with MRSA infections. PMID:27226908

  12. Detection of enterotoxigenic Staphylococcus aureus isolates in domestic dairy products

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    HR Tavakoli

    2010-12-01

    Full Text Available Background and objectives: Staphylococcus aureusis a one of THE most frequent causes of food poisoning (FP in dairy products. The main etiologic agents of FP are staphylococcal enterotoxins (SE. There are different types of SE; types A (SEA and B (SEB are the most clinically important enterotoxins. Traditional dairy products are still produced in small batches and sold by some vendors without a permit from the Ministry of Health. This study focuses on the molecular and serological detection of enterotoxigenic Staphylococcus aureus SEA and SEB genes and its products, respectively from samples of such traditional products."nMaterials and Methods: 100 samples from dairy products were produced under sterile conditions via traditional methods and were transported to the laboratory. The samples were cultured and identified by routine bacteriological methods. The isolated bacteria were evaluated by PCR tests for detection of the genes encoding SEA and SEB. Subsequently, the ability of these strains to produce enterotoxin was examined by Sac's culture method and was confirmed by Sigel Radial Immounodiffussion (SRID."nResults: The results indicated that 32% of the dairy products were contaminated by S. aureus (cream 18% , cheese 10%, milk 4%. The PCR results showed that 15.6% of the S. aureus isolates possessed the SEA gene, 9.3% had the SEB gene, and 6.2% possessed both genes. The evaluation of enterotoxin production indicated that 80% of SEA and 33% of SEB genes were expressed."nConclusion: Enterotoxins SEA and SEB are heat stable and consequently; heating has no effect on dairy products contaminated by entertoxins. Subsequently, gastritis may occur within several hours after consumption. Our findings suggest that PCR is a rapid, sensitive, specific, and inexpensive method for detecting SE and can replace the traditional assays.

  13. Bactericidal antibiotic-phytochemical combinations against methicillin resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Bhone Myint Kyaw

    2012-09-01

    Full Text Available Methicillin resistant Staphylococcus aureus (MRSA infection is a global concern nowadays. Due to its multi-drug resistant nature, treatment with conventional antibiotics does not assure desired clinical outcomes. Therefore, there is a need to find new compounds and/or alternative methods to get arsenal against the pathogen. Combination therapies using conventional antibiotics and phytochemicals fulfill both requirements. In this study, the efficacy of different phytochemicals in combination with selected antibiotics was tested against 12 strains of S. aureus (ATCC MRSA 43300, ATCC methicillin sensitive S. aureus or MSSA 29213 and 10 MRSA clinical strains collected from National University Hospital, Singapore. Out of the six phytochemicals used, tannic acid was synergistic with fusidic acid, minocycline, cefotaxime and rifampicin against most of strains tested and additive with ofloxacin and vancomycin. Quercetin showed synergism with minocycline, fusidic acid and rifampicin against most of the strains. Gallic acid ethyl ester showed additivity against all strains in combination with all antibiotics under investigation except with vancomycin where it showed indifference effect. Eugenol, menthone and caffeic acid showed indifference results against all strains in combination with all antibiotics. Interestingly, no antagonism was observed within these interactions. Based on the fractional inhibitory concentration indices, synergistic pairs were further examined by time-kill assays to confirm the accuracy and killing rate of the combinations over time. The two methods concurred with each other with 92% accuracy and the combinatory pairs were effective throughout the 24 hours of assay. The study suggests a possible incorporation of effective phytochemicals in combination therapies for MRSA infections.

  14. Proteome changes of Caenorhabditis elegans upon a Staphylococcus aureus infection

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    Schoofs Liliane

    2010-02-01

    Full Text Available Abstract Background The success of invertebrates throughout evolution is an excellent illustration of the efficiency of their defence strategies. Caenorhabditis elegans has proven to be an appropriate model for transcriptome studies of host-pathogen interactions. The aim of this paper is to complement this knowledge by investigating the worm's response to a Staphylococcus aureus infection through a 2-dimensional differential proteomics approach. Results Different types of growth media in combination with either E. coli OP50 or Staphylococcus aureus were tested for an effect on the worm's lifespan. LB agar was chosen and C. elegans samples were collected 1 h, 4 h, 8 h and 24 h post S. aureus infection or E. coli incubation. Proteomics analyses resulted in the identification of 130 spots corresponding to a total of 108 differentially expressed proteins. Conclusions Exploring four time-points discloses a dynamic insight of the reaction against a gram-positive infection at the level of the whole organism. The remarkable upregulation after 8 h and 24 h of many enzymes involved in the citric acid cycle might illustrate the cost of fighting off an infection. Intriguing is the downregulation of chaperone molecules, which are presumed to serve a protective role. A comparison with a similar experiment in which C. elegans was infected with the gram-negative Aeromonas hydrophila reveals that merely 9% of the identified spots, some of which even exhibiting an opposite regulation, are present in both studies. Hence, our findings emphasise the complexity and pathogen-specificity of the worm's immune response and form a firm basis for future functional research. Reviewers This article was reviewed by Itai Yanai, Dieter Wolf and Torben Luebke (nominated by Walter Lutz.

  15. Staphylococcus aureus detection in the mouth of housekeepers Detección de Staphylococcus aureus en la boca de trabajadores de la limpieza hospitalaria Detecção de Staphylococcus aureus na boca de trabalhadores da limpeza hospitalar

    Directory of Open Access Journals (Sweden)

    Elaine Drehmer de Almeida Cruz

    2011-02-01

    Full Text Available This study assessed the prevalence of colonization by Staphylococcus aureus in hospital housekeepers, and their knowledge and beliefs regarding this problem. Three saliva samples were collected and a questionnaire regarding knowledge and beliefs was applied. Of the 92 workers, 63 (68.5% participated in the study; 20 were not and 43 were colonized; 13 by methicillin resistant Staphylococcus aureus and 30 by methicillin sensitive Staphylococcus aureus. Persistent carrier status of methicillin resistant Staphylococcus aureus was detected in 15.4% of cases. Low knowledge and perception of occupational risk were observed. The mouth was identified as an important reservoir of methicillin resistant Staphylococcus aureus. Analyzing knowledge and beliefs, as well as the state of carrier, is an important strategy to be added to educational actions for the prevention of workers' colonization.Este estudio evaluó la prevalencia de la colonización por Staphylococcus aureus en trabajadores de limpieza hospitalaria, y su conocimiento y creencias acerca de la problemática. Fueron recolectadas tres muestras de saliva y aplicado un cuestionario referente al conocimiento y creencias. De 92 trabajadores, 63 (68,5% participaron del estudio; 20 se presentaron no colonizados y 43 colonizados; 13 para Staphylococcus aureus resistente a la meticilina y 30 para Staphylococcus aureus sensibles a la meticilina. El estado de portador persistente por Staphylococcus aureus resistente a la meticilina fue detectado en 15,4% de los casos. Bajo conocimiento y percepción del riesgo ocupacional fueron observados. La boca fue identificada como importante reservatorio de Staphylococcus aureus resistente a la meticilina. Analizar el conocimiento y creencias juntamente con la investigación del estado de portador es una importante estrategia a ser agregada a las acciones educativas para la prevención de la colonización de trabajadores.Este estudo avaliou a prevalência da coloniza

  16. Schistosoma spindale infection in a captive jackal (Canis aureus).

    Science.gov (United States)

    Vimalraj, P G; Latchumikanthan, A

    2015-03-01

    This report is based on the findings from a captive jackal (Canis aureus) housed in Amirthi Zoological Park, Javadu Hills, Vellore. The animal was reported to be dull, depressed and also had diarrhea. Fecal samples were collected in 10 % formalin and subjected to direct and sedimentation method of faecal examination and was examined for endoparasitic infection. Surprisingly, fecal examination revealed two spindle shaped eggs having terminal spine with a size of 250μ by 60μ. The eggs were identified as belonging to Schistosoma spindale and as per the standard keys (Soulsby 1982). PMID:25698875

  17. In vivo genome editing using Staphylococcus aureus Cas9

    OpenAIRE

    Ran, F Ann; Cong, Le; Yan, Winston X.; Scott, David A.; Gootenberg, Jonathan S.; Kriz, Andrea J.; Zetsche, Bernd; Shalem, Ophir; Wu, Xuebing; Makarova, Kira S.; Koonin, Eugene; Sharp, Phillip A.; Zhang, Feng

    2015-01-01

    The RNA-guided endonuclease Cas9 has emerged as a versatile genome-editing platform. However, the size of the commonly used Cas9 from Streptococcus pyogenes (SpCas9) limits its utility for basic research and therapeutic applications that employ the highly versatile adeno-associated virus (AAV) delivery vehicle. Here, we characterize six smaller Cas9 orthologs and show that Cas9 from Staphylococcus aureus (SaCas9) can edit the genome with efficiencies similar to those of SpCas9, while being >1...

  18. Epidemic Increase in Methicillin-resistant Staphylococcus aureus in Copenhagen

    DEFF Research Database (Denmark)

    Westh, Henrik; Boye, Kit; Bartels, Mette Damkjær;

    2006-01-01

    INTRODUCTION: We have found an epidemic increase in methicillin-resistant Staphylococcus aureus (MRSA) in Copenhagen. The increase has a complex background and involves hospitals, nursing homes and persons nursed in their own home. MATERIAL AND METHODS: We found 33 MRSA patients in 2003 and 121 in...... 2004. All isolates have been spa-typed and epidemiologic information collected. RESULTS: The number of MRSA cases has a doubling time of about six months. The epidemic has been caused by many different MRSA types and 31 staphylococcus protein A genotypes (spa types). MRSA has caused several hospital...

  19. Epidemic Increase in Methicillin-resistant Staphylococcus aureus in Copenhagen

    DEFF Research Database (Denmark)

    Westh, Henrik; Boye, Kit; Bartels, Mette Damkjær;

    2006-01-01

    INTRODUCTION: We have found an epidemic increase in methicillin-resistant Staphylococcus aureus (MRSA) in Copenhagen. The increase has a complex background and involves hospitals, nursing homes and persons nursed in their own home. MATERIAL AND METHODS: We found 33 MRSA patients in 2003 and 121...... in 2004. All isolates have been spa-typed and epidemiologic information collected. RESULTS: The number of MRSA cases has a doubling time of about six months. The epidemic has been caused by many different MRSA types and 31 staphylococcus protein A genotypes (spa types). MRSA has caused several hospital...

  20. Modulation of Neutrophil Chemokine Receptors by Staphylococcus aureus Supernate

    OpenAIRE

    Veldkamp, K. E.; Heezius, H. C. J. M.; Verhoef, J; Strijp, J.A.G. van; van Kessel, K. P. M.

    2000-01-01

    In a previous study, we showed that Staphylococcus aureus supernate (SaS) is a potent agonist for both neutrophils and mononuclear cells. To further investigate the immunomodulating effects of SaS, the effect on different neutrophil receptors was studied. Expression of various neutrophil receptors, before and after treatment with SaS, was quantified by flow cytometry. We found that SaS treatment of neutrophils resulted in a specific and total downregulation of the C5a and the fMLP receptor, b...

  1. Inhibition of methicillin resistant Staphylococcus aureus by a plasma needle

    Science.gov (United States)

    Miletić, Maja; Vuković, Dragana; Živanović, Irena; Dakić, Ivana; Soldatović, Ivan; Maletić, Dejan; Lazović, Saša; Malović, Gordana; Petrović, Zoran; Puač, Nevena

    2014-03-01

    In numerous recent papers plasma chemistry of non equilibrium plasma sources operating at atmospheric pressure has been linked to plasma medical effects including sterilization. In this paper we present a study of the effectiveness of an atmospheric pressure plasma source, known as plasma needle, in inhibition of the growth of biofilm produced by methicillin resistant Staphylococcus aureus (MRSA). Even at the lowest powers the biofilms formed by inoculi of MRSA of 104 and 105 CFU have been strongly affected by plasma and growth in biofilms was inhibited. The eradication of the already formed biofilm was not achieved and it is required to go to more effective sources.

  2. Binding of collagen to Staphylococcus aureus Cowan 1.

    OpenAIRE

    Speziale, P; Raucci, G; Visai, L.; Switalski, L M; Timpl, R; Höök, M

    1986-01-01

    Collagen binds to a receptor protein present on the surfaces of Staphylococcus aureus cells. Binding of 125I-labeled type II collagen to its bacterial receptor is reversible, and Scatchard plot analysis indicates the presence of one class of receptor that occurs on an average of 3 X 10(4) copies per cell and binds type II collagen with a Kd of 10(-7) M. Studies on the specificity of collagen cell binding indicate that the receptor does not recognize noncollagenous proteins but binds all of th...

  3. STAPHYLOCOCCUS AUREUS BIOFILM FORMATION ON POLYPYRROLE: AN ELECTRICAL OVERVIEW

    Directory of Open Access Journals (Sweden)

    Erlon R. Cordeiro

    2015-09-01

    Full Text Available The development of organic devices based on conducting polymers for biofilm detection requires the combination of superior electrical response and high surface area for biofilm incorporation. Polypyrrole is a potential candidate for application in biofilm detection and control due to its characteristic superior electrical response and strong interaction with bacteria, which enables the use of the bioelectric effect in resulting devices. In this study, chemically synthesized polypyrrole was applied as a support for biofilm growth of S. aureus. Modifications in the electrical response of the polymeric template were explored to identify general mechanisms established during the deposition of the biofilm.

  4. Cell wall sorting of lipoproteins in Staphylococcus aureus.

    OpenAIRE

    Navarre, W W; Daefler, S; Schneewind, O

    1996-01-01

    Many surface proteins are thought to be anchored to the cell wall of gram-positive organisms via their C termini, while the N-terminal domains of these molecules are displayed on the bacterial surface. Cell wall anchoring of surface proteins in Staphylococcus aureus requires both an N-terminal leader peptide and a C-terminal cell wall sorting signal. By fusing the cell wall sorting of protein A to the C terminus of staphylococcal beta-lactamase, we demonstrate here that lipoproteins can also ...

  5. Key role for clumping factor B in Staphylococcus aureus nasal colonization of humans

    NARCIS (Netherlands)

    H.F.L. Wertheim (Heiman); E.J. Walsh (Evelyn); R.S.R. Choudhurry (Roos); D.C. Melles (Damian); H.A.M. Boelens (Hélène); H. Miajlovic (Helen); H.A. Verbrugh (Henri); T.J. Foster (Timothy); A.F. van Belkum (Alex)

    2008-01-01

    textabstractBACKGROUND: Staphylococcus aureus permanently colonizes the vestibulum nasi of one-fifth of the human population, which is a risk factor for autoinfection. The precise mechanisms whereby S. aureus colonizes the nose are still unknown. The staphylococcal cell-wall protein clumping factor

  6. Loop-Mediated Isothermal Amplification Assay for the Rapid Detection of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    King Ting Lim

    2013-01-01

    Full Text Available Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA, is an important human pathogen that produces a variety of toxins and causes a wide range of infections, including soft-tissue infections, bacteremia, and staphylococcal food poisoning. A loop-mediated isothermal amplification (LAMP assay targeting the arcC gene of S. aureus was developed and evaluated with 119 S. aureus and 25 non-S. aureus strains. The usefulness of the assay was compared with the PCR method that targets spa and arcC genes. The optimal temperature for the LAMP assay was 58.5°C with a detection limit of 2.5 ng/μL and 102 CFU/mL when compared to 12.5 ng/μL and 103 CFU/mL for PCR (spa and arcC. Both LAMP and PCR assays were 100% specific, 100% sensitive, 100% positive predictive value (PPV, and 100% negative predictive value (NPV. When tested on 30 spiked blood specimens (21 MRSA, eight non-S. aureus and one negative control, the performance of LAMP and PCR was comparable: 100% specific, 100% sensitive, 100% PPV, and 100% NPV. In conclusion, the LAMP assay was equally specific with a shorter detection time when compared to PCR in the identification of S. aureus. The LAMP assay is a promising alternative method for the rapid identification of S. aureus and could be used in resource-limited laboratories and fields.

  7. Staphylococcus aureus genotype B and other genotypes isolated from cow milk in European countries.

    Science.gov (United States)

    Cosandey, A; Boss, R; Luini, M; Artursson, K; Bardiau, M; Breitenwieser, F; Hehenberger, E; Lam, Th; Mansfeld, M; Michel, A; Mösslacher, G; Naskova, J; Nelson, S; Podpečan, O; Raemy, A; Ryan, E; Salat, O; Zangerl, P; Steiner, A; Graber, H U

    2016-01-01

    Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies, however, have demonstrated in Swiss cows that Staph. aureus isolated from bovine intramammary infection is genetically heterogeneous, with Staph. aureus genotype B (GTB) and GTC being the most prominent genotypes. In addition, Staph. aureus GTB was found to be contagious, whereas Staph. aureus GTC and all the remaining genotypes were involved in individual cow disease. The aim of this study was to subtype strains of Staph. aureus isolated from bovine mastitic milk and bulk tank milk to obtain a unified view of the presence of bovine staphylococcal subtypes in 12 European countries. A total of 456 strains of Staph. aureus were subjected to different typing methods: ribosomal spacer PCR, detection of enterotoxin genes, and detection of gene polymorphisms (lukE, coa). Major genotypes with their variants were combined into genotypic clusters (CL). This study revealed 5 major CL representing 76% of all strains and comprised CLB, CLC, CLF, CLI, and CLR. The clusters were characterized by the same genetic properties as the Swiss isolates, demonstrating high clonality of bovine Staph. aureus. Interestingly, CLB was situated in central Europe whereas the other CL were widely disseminated. The remaining 24% of the strains comprised 41 genotypes and variants, some of which (GTAM, GTBG) were restricted to certain countries; many others, however, were observed only once. PMID:26585469

  8. Mechanism and consequences of invasion of endothelial cells by Staphylococcus aureus

    NARCIS (Netherlands)

    Sinha, Bhanu; Herrmann, Mathias

    2005-01-01

    It has become clear that Staphylococcus aureus is a facultative intracellular microorganism. Adherence and invasion are a prerequisite for endovascular infections caused by S. aureus, such as infective endocarditis. These phenomena may also be involved in the pathogenesis of invasive and metastatic

  9. Characterization of Staphylococcus aureus isolates from pediatric patients with cystic fibrosis.

    Science.gov (United States)

    Liu, Ying; Zhang, Jiang; Zhong, Dengke; Ji, Lu; Yang, Junshu; Phillips, James; Ji, Yinduo

    2016-10-01

    Staphylococcus aureus is one of the major respiratory pathogens associated with cystic fibrosis (CF) patients. In this study, we collected sputum and isolated fifty S. aureus isolates from CF patients with the median age of 9.5 years old. Then we determined the profiles of these isolates by antibiotic susceptibility testing, examining their cytotoxicity and ability to internalize into an epithelial cell line (A549), as well as multiple loci sequencing typing. Predominant CF S. aureus isolates were resistant to penicillin; however, these isolates were sensitive to various antibiotics, such as vancomycin and minocycline. Different CF S. aureus isolates showed distinct cytotoxic activities, and 90 % of CF S. aureus isolates possessed the enterotoxin genes, sea and hlg. Moreover, we found that multiple different CF S. aureus isolates appeared to have the distinct capacity of invading A549 cells. ST5 (14 %), ST30 (14 %), and ST8 (10 %) were prevalent ST types in these isolates. Further analysis revealed that ST5 and ST30 isolates were less toxic than ST8 and ST15 isolates, and that the ST5, ST15, ST59, and ST87 types of CF S. aureus were less capable of invading A549 cells. Our results suggest that the ST typing method may be useful in predicting cytotoxicity and the invading capacity of S. aureus isolates from patients with CF. PMID:27562596

  10. Methicillin-Resistant "Staphylococcus aureus" on Campus: A New Challenge to College Health

    Science.gov (United States)

    Weiner, H. Richard

    2008-01-01

    As new drugs to control bacterial pathogens are developed, the organisms evolve to survive. "Staphylococcus aureus", a common organism, has steadily developed resistance to antibiotics. For more than 40 years, resistant "S. aureus" presented a formidable problem to hospitalized patients; in the past decade, however, it has begun to appear outside…

  11. Community-Acquired Methicillin-Resistant "Staphylococcus aureus": Considerations for School Nurses

    Science.gov (United States)

    Alex, Aniltta; Letizia, MariJo

    2007-01-01

    Methicillin-resistant "Staphylococcus aureus" (MRSA) is a disease-causing organism that has been present in hospital settings since the 1960s. However, a genetically distinct strain of MRSA, called community-acquired methicillin-resistant "Staphylococcus aureus" (CA-MRSA), has emerged in recent years in community settings among healthy…

  12. Direct detection of nasal Staphylococcus aureus carriage via helicase-dependent isothermal amplification and chip hybridization

    Directory of Open Access Journals (Sweden)

    Frech Georges C

    2012-08-01

    Full Text Available Abstract Background The bacterium Staphylococcus aureus constitutes one of the most important causes of nosocomial infections. One out of every three individuals naturally carries S. aureus in their anterior nares, and nasal carriage is associated with a significantly higher infection rate in hospital settings. Nasal carriage can be either persistent or intermittent, and it is the persistent carriers who, as a group, are at the highest risk of infection and who have the highest nasal S. aureus cell counts. Prophylactic decolonization of S. aureus from patients’ noses is known to reduce the incidence of postsurgical infections, and there is a clear rationale for rapid identification of nasal S. aureus carriers among hospital patients. Findings A molecular diagnostic assay was developed which is based on helicase-dependent target amplification and amplicon detection by chip hybridization to a chip surface, producing a visible readout. Nasal swabs from 70 subjects were used to compare the molecular assay against culturing on “CHROMagar Staph aureus” agar plates. The overall relative sensitivity was 89%, and the relative specificity was 94%. The sensitivity rose to 100% when excluding low-count subjects (S. aureus colony-forming units per swab. Conclusions This molecular assay is much faster than direct culture and has sensitivity that is appropriate for identification of high-count (>100 S. aureus colony-forming units per swab nasal S. aureus carriers who are at greatest risk for nosocomial infections.

  13. Prevalence and antibiogram study of Salmonella and Staphylococcus aureus in poultry meat

    Institute of Scientific and Technical Information of China (English)

    Ali Akbar; Anil Kumar Anal

    2013-01-01

    Objective:To evaluate the presence and antibiogram pattern of Salmonella and Staphylococcus aureus (S. aureus) in retail poultry meat products. Methods: Foodborne pathogens (Salmonella and S. aureus) were isolated from poultry meat and confirmed with the help of biochemical and immunological test. Antibiogram of the isolates were examined by following CLSI methods. Results: A total number of 209 poultry meat samples were collected and studied in this study. Out of which, 5.26%were found contaminated with Salmonella while 18.18%were found contaminated with S. aureus. All the Salmonella and S. aureus isolates were found resistant to at least one antibiotic. About 72.72%of the Salmonella isolates showed resistance to tetracycline, while S. aureus isolates were also found highly resistant to tetracycline equal to 44.73%. One of the Salmonella isolates showed multi-drug resistance to almost six antibiotics out of nine antibiotics used in the study. Multidrug resistant S. aureus isolates were also found in the study. Conclusions: The study confirmed the presence of Salmonella and S. aureus in retail poultry meat. It is a potential threat to consumer health. To reduce the risk of contamination, good hygiene practices are necessary from processing to storage.

  14. Prevalence of coagulase gene polymorphism in Staphylococcus aureus isolates causing bovine mastitis

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Dangler, C. A.; Sordillo, L. M.

    1995-01-01

    This study was conducted to investigate polymorphism of the coagulase gene of Staphylococcus aureus causing bovine mastitis. One hundred eighty-seven strains of S. aureus were isolated from bovine mastitic milk samples obtained from 187 different Danish dairy farms. The isolates were characterised...

  15. Physicochemical characterization of Staphylococcus aureus-lysing LysK enzyme in complexes with polycationic

    Science.gov (United States)

    Staphylococcus aureus causes many serious visceral, skin, and respiratory diseases. About 90% of clinical strains are multi-drug resistant, but the use of bacteriophage lytic enzymes offers a viable alternative to antibiotic therapy. LysK, the phage K endolysin can lyse S. aureus when purified and ...

  16. Triple-acting Peptidoglycan hydrolase treatment for drug-resistant and intracellular Staphylococcus aureus

    Science.gov (United States)

    Multi-drug resistant bacteria are a persistent problem in modern health care, food safety and animal health. There is a need for new antimicrobials to replace over-used conventional antibiotics. Staphylococcus aureus (S. aureus) is a notorious pathogen for both animal and human health with multi-d...

  17. Rapid identification and classification of Staphylococcus aureus by attenuated total reflectance fourier transform infrared spectroscopy

    Science.gov (United States)

    Staphylococcus aureus is an important bacterium that can cause serious infections in humans such as pneumonia and bacteremia. Rapid detection of this pathogen is crucial in food industries and clinical laboratories to control S. aureus food poisoning and human infections. In this study, fourier tran...

  18. Human-associated methicillin-resistant Staphylococcus aureus from a subtropical recreational marine beach

    Science.gov (United States)

    Reports of Staphylococcus aureus detected in marine environments have occurred since the early 1990’s. This investigation sought to isolate and characterize S. aureus from marine waters and sand at a subtropical recreational beach, with and without bathers present, in order to investigate possible s...

  19. Characterization and comparative analysis of a second thermonuclease in Staphylococcus aureus

    Science.gov (United States)

    Staphylococcal nuclease (here termed as NUC1) is considered an important virulence factor and a unique marker widely used in detection of Staphylococcus aureus. A novel functional thermostable nuclease (here termed as NUC2) in S. aureus was characterized after recombinant expression in Escherichia...

  20. Triple-acting antimicrobial treatment for drug-resistant and intracellular Staphylococcus aureus

    Science.gov (United States)

    Multi-drug resistant bacteria are a persistent problem in modern health care, food safety and animal health. There is a need for new antimicrobials to replace over-used conventional antibiotics. Staphylococcus aureus (S. aureus) is a notorious pathogen for both animal and human health with multi-d...

  1. Comparison of difloxacin, enoxacin, and cefazolin for the treatment of experimental Staphylococcus aureus endocarditis.

    OpenAIRE

    Boscia, J A; Kobasa, W D; Kaye, D

    1988-01-01

    This study compared difloxacin administered orally, enoxacin administered orally, and cefazolin administered intramuscularly for the treatment of experimental Staphylococcus aureus endocarditis. Difloxacin significantly reduced bacterial counts of vegetations compared with enoxacin. This study demonstrated that difloxacin was significantly more effective than enoxacin and as effective as cefazolin for the treatment of S. aureus endocarditis in rabbits.

  2. A systematic review and meta-analysis on Staphylococcus aureus carriage in psoriasis, acne and rosacea

    NARCIS (Netherlands)

    J. Totte (Joan); W.T. van der Feltz; L.G.M. Bode (Lonneke); A.F. van Belkum (Alex); E.J. Van Zuuren; S.G.M.A. Pasmans (Suzanne)

    2016-01-01

    textabstractStaphylococcus aureus might amplify symptoms in chronic inflammatory skin diseases. This study evaluates skin and mucosal colonization with S. aureus in patients with psoriasis, acne and rosacea. A systematic literature search was conducted. Both odds ratios (OR) for colonization in pati

  3. Occurrence and distribution of Staphylococcus aureus lineages among zoo animals

    DEFF Research Database (Denmark)

    Gongora, Carmen Espinosa; Chrobak, Dorota; Moodley, Arshnee;

    2012-01-01

    occurrence and genotypic diversity of S. aureus in a range of animal species kept at the Copenhagen Zoo. We sampled 146 animals belonging to 25 mammalian species and 21 reptiles belonging to six species. A total of 59 S. aureus isolates were found in 10 of the 25 mammalian species tested. All isolates were...

  4. Rapid Staphylococcus aureus agr Type Determination by a Novel Multiplex Real-Time Quantitative PCR Assay

    OpenAIRE

    Francois, Patrice; Koessler, Thibaud; Huyghe, Antoine; Harbarth, Stephan; Bento, Manuela; Lew, Daniel; Etienne, Jérôme; Pittet, Didier; Schrenzel, Jacques

    2006-01-01

    The accessory gene regulator (agr) is a crucial regulatory component of Staphylococcus aureus involved in the control of bacterial virulence factor expression. We developed a real-time multiplex quantitative PCR assay for the rapid determination of S. aureus agr type. This assay represents a rapid and affordable alternative to sequence-based strategies for assessing relevant epidemiological information.

  5. Rapid Staphylococcus aureus agr type determination by a novel multiplex real-time quantitative PCR assay.

    Science.gov (United States)

    Francois, Patrice; Koessler, Thibaud; Huyghe, Antoine; Harbarth, Stephan; Bento, Manuela; Lew, Daniel; Etienne, Jérôme; Pittet, Didier; Schrenzel, Jacques

    2006-05-01

    The accessory gene regulator (agr) is a crucial regulatory component of Staphylococcus aureus involved in the control of bacterial virulence factor expression. We developed a real-time multiplex quantitative PCR assay for the rapid determination of S. aureus agr type. This assay represents a rapid and affordable alternative to sequence-based strategies for assessing relevant epidemiological information. PMID:16672433

  6. Rapid Staphylococcus aureus agr Type Determination by a Novel Multiplex Real-Time Quantitative PCR Assay

    Science.gov (United States)

    Francois, Patrice; Koessler, Thibaud; Huyghe, Antoine; Harbarth, Stephan; Bento, Manuela; Lew, Daniel; Etienne, Jérôme; Pittet, Didier; Schrenzel, Jacques

    2006-01-01

    The accessory gene regulator (agr) is a crucial regulatory component of Staphylococcus aureus involved in the control of bacterial virulence factor expression. We developed a real-time multiplex quantitative PCR assay for the rapid determination of S. aureus agr type. This assay represents a rapid and affordable alternative to sequence-based strategies for assessing relevant epidemiological information. PMID:16672433

  7. Heterologously expressed Staphylococcus aureus fibronectin-binding proteins are sufficient for invasion of host cells

    NARCIS (Netherlands)

    Sinha, B; Francois, P; Que, Y A; Hussain, M; Heilmann, C; Moreillon, P; Lew, D; Krause, K H; Peters, G; Herrmann, M

    2000-01-01

    Staphylococcus aureus invasion of mammalian cells, including epithelial, endothelial, and fibroblastic cells, critically depends on fibronectin bridging between S. aureus fibronectin-binding proteins (FnBPs) and the host fibronectin receptor integrin alpha(5)beta(1) (B. Sinha et al., Cell. Microbiol

  8. Antibacterial activity of some commonly used food commodities against escherichia coli, salmonella typhi and staphylococcus aureus

    International Nuclear Information System (INIS)

    The activity of commonly used spices and salt, sugar and pickles against Escherichia coli, Salmonella typhi and staphlococcus aureus was tested. The antibacterial activity was found to be in descending order like coriander>pickles>salt and sugar>clove>black pepper>red chilli against S. typhi and garlic>clove>onion>ginger against S. aureus. (author)

  9. Mupirocin prophylaxis against nosocomial Staphylococcus aureus infections in nonsurgical patients: a randomized study.

    NARCIS (Netherlands)

    Wertheim, H.F.; Vos, A.M.C.; Ott, A.; Voss, A.; Kluytmans, J.A.J.W.; Broucke-Grauls, C.M. van den; Meester, M.; Keulen, P.H. van; Verbrugh, H.A.

    2004-01-01

    BACKGROUND: Staphylococcus aureus nasal carriage is a major risk factor for nosocomial S. aureus infection. Studies show that intranasal mupirocin can prevent nosocomial surgical site infections. No data are available on the efficacy of mupirocin in nonsurgical patients. OBJECTIVE: To assess the eff

  10. Influence of antibiotic pressure on bacterial bioluminescence, with emphasis on Staphylococcus aureus

    NARCIS (Netherlands)

    Daghighi, Seyedmojtaba; Sjollema, Jelmer; Harapanahalli, Akshay; Dijkstra, Rene J. B.; van der Mei, Henny C.; Busscher, Henk J.

    2015-01-01

    Bioluminescence imaging is used for longitudinal evaluation of bacteria in live animals. Clear relations exist between bacterial numbers and their bioluminescence. However, bioluminescence images of Staphylococcus aureus Xen29, S. aureus Xen36 and Escherichia coli Xen14 grown on tryptone soy agar in

  11. Killing of Staphylococcus aureus via Magnetic Hyperthermia Mediated by Magnetotactic Bacteria.

    Science.gov (United States)

    Chen, Changyou; Chen, Linjie; Yi, Yong; Chen, Chuanfang; Wu, Long-Fei; Song, Tao

    2016-01-01

    Staphylococcus aureus is a common hospital and household pathogen. Given the emergence of antibiotic-resistant derivatives of this pathogen resulting from the use of antibiotics as general treatment, development of alternative therapeutic strategies is urgently needed. Here, we assess the feasibility of killing S. aureus cells in vitro and in vivo through magnetic hyperthermia mediated by magnetotactic bacteria that possess magnetic nanocrystals and demonstrate magnetically steered swimming. The S. aureus suspension was added to magnetotactic MO-1 bacteria either directly or after coating with anti-MO-1 polyclonal antibodies. The suspensions were then subjected to an alternating magnetic field (AMF) for 1 h. S. aureus viability was subsequently assessed through conventional plate counting and flow cytometry. We found that approximately 30% of the S. aureus cells mixed with uncoated MO-1 cells were killed after AMF treatment. Moreover, attachment between the magnetotactic bacteria and S. aureus increased the killing efficiency of hyperthermia to more than 50%. Using mouse models, we demonstrated that magnetic hyperthermia mediated by antibody-coated magnetotactic MO-1 bacteria significantly improved wound healing. These results collectively demonstrated the effective eradication of S. aureus both in vitro and in vivo, indicating the potential of magnetotactic bacterium-mediated magnetic hyperthermia as a treatment for S. aureus-induced skin or wound infections. PMID:26873320

  12. A Comparative Analysis of Community Acquired and Hospital Acquired Methicillin Resistant Staphylococcus Aureus

    OpenAIRE

    P R, Vysakh; M, Jeya

    2013-01-01

    Purpose: Staphylococcus aureus has developed resistance against most of the therapeutic agents. The most notable example of this phenomenon was the emergence of Methicillin resistant Staphylococcus aureus (MRSA). We are reporting the prevalence and the antibiotic susceptibility pattern of the MRSA isolates from a tertiary care hospital.

  13. Correlation between Reduced Daptomycin Susceptibility and Vancomycin Resistance in Vancomycin-Intermediate Staphylococcus aureus

    OpenAIRE

    Cui, Longzhu; Tominaga, Eiji; Neoh, Hui-min; Hiramatsu, Keiichi

    2006-01-01

    We present here findings of a strong positive correlation between reduced daptomycin susceptibility and vancomycin resistance in vancomycin-intermediate Staphylococcus aureus (VISA). This correlation is related to cell wall thickening, suggesting that, similar to the case with vancomycin resistance in VISA, the physical barrier of a thickened cell wall may contribute to daptomycin resistance in S. aureus.

  14. Neutrophil-generated oxidative stress and protein damage in Staphylococcus aureus.

    Science.gov (United States)

    Beavers, William N; Skaar, Eric P

    2016-08-01

    Staphylococcus aureus is a ubiquitous, versatile and dangerous pathogen. It colonizes over 30% of the human population, and is one of the leading causes of death by an infectious agent. During S. aureus colonization and invasion, leukocytes are recruited to the site of infection. To combat S. aureus, leukocytes generate an arsenal of reactive species including superoxide, hydrogen peroxide, nitric oxide and hypohalous acids that modify and inactivate cellular macromolecules, resulting in growth defects or death. When S. aureus colonization cannot be cleared by the immune system, antibiotic treatment is necessary and can be effective. Yet, this organism quickly gains resistance to each new antibiotic it encounters. Therefore, it is in the interest of human health to acquire a deeper understanding of how S. aureus evades killing by the immune system. Advances in this field will have implications for the design of future S. aureus treatments that complement and assist the host immune response. In that regard, this review focuses on how S. aureus avoids host-generated oxidative stress, and discusses the mechanisms used by S. aureus to survive oxidative damage including antioxidants, direct repair of damaged proteins, sensing oxidant stress and transcriptional changes. This review will elucidate areas for studies to identify and validate future antimicrobial targets. PMID:27354296

  15. Comparative analysis of conjugative plasmids mediating gentamicin resistance in Staphylococcus aureus.

    OpenAIRE

    Goering, R. V.; Ruff, E A

    1983-01-01

    Five gentamicin-resistant clinical isolates of Staphylococcus aureus were found to contain self-transmissible plasmids of 32 to 37 megadaltons in size. Restriction endonuclease digests of the plasmids were markedly similar to those of reference plasmids of unrelated geographical origin, thus suggesting the significant contribution of common conjugal plasmids to the emergence of gentamicin resistance in S. aureus populations.

  16. Uptake of sparfloxacin and norfloxacin by clinical isolates of Staphylococcus aureus.

    OpenAIRE

    Yoshida, S.(Department of Physics, Chiba University, 263-8522, Chiba, Japan); Kojima, T.; M. Inoue; Mitsuhashi, S

    1991-01-01

    The amount of sparfloxacin uptake was higher than that of norfloxacin uptake in Staphylococcus aureus. Moreover, energy-dependent reduction in quinolone uptake, probably due to active efflux of the quinolone, was observed. The reduction in quinolone uptake appeared to be associated with quinolone resistance in S. aureus.

  17. Rapid first-line discrimination of methicillin resistant Staphylococcus aureus strains using MALDI-TOF MS

    DEFF Research Database (Denmark)

    Østergaard, Claus; Grønvall Kjær Hansen, Sanne; Møller, Jens K

    2015-01-01

    Fast and reliable discrimination of methicillin-resistant Staphylococcus aureus (MRSA) isolates is essential in identifying an outbreak. Molecular typing methods, such as S. aureus protein A (spa) typing, multi locus sequence typing (MLST) and pulse field gel electrophoresis (PFGE) are generally...

  18. Nosocomial Staphylococcus Aureus Bacterimia among Nasal Carriers of Methicillin- Resistant and Methicillin-Susceptible Strains

    NARCIS (Netherlands)

    M. Pujol (Miquel); C. Pena; R. Pallares (Roman); J. Ariza (Javier); J. Ayats (Josefina); M.A. Dominguez; F. Gudiol (Francesc)

    1996-01-01

    textabstractObjectives To determine the relevance of nasal carriage of Staphylococcus aureus, either methicillin-sensitive (MSSA) or methicillinresistant (MRSA), as a risk factor for the development of nosocomial S aureus bacteremia during an MRSA outbreak. patients and methods: In this prospective

  19. Systemic Staphylococcus aureus infection mediated by Candida albicans hyphal invasion of mucosal tissue

    NARCIS (Netherlands)

    L.M. Schlecht; B.M. Peters; B.P. Krom; J.A. Freiberg; G.M. Hänsch; S.G. Filler; M.A. Jabra-Rizk; M.E. Shirtliff

    2015-01-01

    Candida albicans and Staphylococcus aureus are often co-isolated in cases of biofilm-associated infections. C. albicans can cause systemic disease through morphological switch from the rounded yeast to the invasive hyphal form. Alternatively, systemic S. aureus infections arise from seeding through

  20. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

    NARCIS (Netherlands)

    A.F. Brown (Aisling F.); A.G. Murphy (Alison G.); S.J. Lalor (Stephen J.); J.M. Leech (John M.); K.M. O’Keeffe (Kate M.); M. Mac Aogáin (Micheál); D.P. O’Halloran (Dara P.); K.A. Lacey (Keenan A.); M. Tavakol (Mehri); C.H. Hearnden (Claire H.); D. Fitzgerald-Hughes (Deirdre); H. Humphreys (Hilary); J.P. Fennell (Jérôme P.); W.J.B. van Wamel (Willem); T.J. Foster (Timothy J.); J.A. Geoghegan (Joan A.); E.C. Lavelle (Ed C.); T.R. Rogers (Thomas R.); R.M. McLoughlin (Rachel M.)

    2015-01-01

    textabstractMechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrate

  1. Future challenges and treatment of Staphylococcus aureus bacteremia with emphasis on MRSA

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Fowler, Vance G; Skov, Robert;

    2011-01-01

    . Compounding this problem is the growing prevalence of methicillin-resistant S. aureus (MRSA) and the dwindling efficacy of vancomycin, long the treatment of choice for this pathogen. Despite the recent availability of several new antibiotics for S. aureus, new strategies for treatment and prevention are...

  2. Methicillin (Oxacillin)-Resistant Staphylococcus aureus Strains Isolated from Major Food Animals and Their Potential Transmission to Humans

    OpenAIRE

    Lee, John Hwa

    2003-01-01

    From May 2001 to April 2003, various types of specimens from cattle, pigs, and chickens were collected and examined for the presence of methicillin (oxacillin)-resistant Staphylococcus aureus (MRSA). S. aureus was isolated and positively identified by using Gram staining, colony morphology, tests for coagulase and urease activities, and an API Staph Ident system. Among 1,913 specimens collected from the animals, 421 contained S. aureus; of these, 28 contained S. aureus resistant to concentrat...

  3. Subinhibitory concentrations of imipenem induce increased resistance to methicillin and imipenem in vitro in methicillin-resistant Staphylococcus aureus.

    OpenAIRE

    Forbes, B A; McClatchey, K D; Schaberg, D R

    1984-01-01

    Methicillin-resistant (MR) Staphylococcus aureus that was susceptible to less than 0.75 micrograms of imipenem per ml demonstrated inducible resistance. MR S. aureus preincubated with 0.05 microgram of imipenem per ml grew in medium with an imipenem concentration of 32 micrograms/ml, and methicillin MICs increased 20-fold. Non-MR S. aureus exhibited no induction. Preincubation with methicillin produced no effect. Induction appeared to be a unique interaction of imipenem with MR S. aureus.

  4. Structural Analysis of Serine/Threonine Protein Kinase B and Multiple Peptide Resistant Factor of Staphylococcus aureus

    OpenAIRE

    Rakette, Sonja

    2012-01-01

    Staphylococcus aureus (S. aureus) infections are becoming increasingly problematic. The bacteria gain resistance to new antibiotics in relatively short time periods. Besides the hospital associated methicillin-resistant S. aureus (HA-MRSA), infections with community-associated MRSA (CA-MRSA) are increasing. The only serine/threonine kinase PknB of S. aureus is composed of an intracellular kinase domain, a transmembrane helix and three extracellular penicillin-binding protein and serine/th...

  5. Significado de la fiebre persistente o recurrente durante el tratamiento de la endocarditis infecciosa Clinical significance of persistent or recurrent fever during the treatment of infective endocarditis

    Directory of Open Access Journals (Sweden)

    José Carena

    2004-06-01

    Full Text Available Se evaluaron 81 pacientes con endocarditis infecciosa con el objeto de establecer la significación clínica de la presencia de fiebre persistente (FP y/o fiebre recurrente (FR durante el tratamiento. Un total de 46 pacientes (56.8% (Grupo 1 tuvieron FP y/o FR durante el tratamiento: 35 FP y 16 FR, que se compararon con 35 sin FP/FR (Grupo 2. No hubo diferencias en la edad, sexo, permanencia hospitalaria, origen nosocomial, demora diagnóstica y comorbilidad asociada. El compromiso aórtico (47.8 vs 34.2% y tricuspídeo (21.7 vs 11.4% y la infección por Staphylococcus aureus (55.5 vs 28% fueron más frecuentes en el Grupo 1, aunque no significativamente. El S. aureus meticilino resistente (SAMR (22.2 vs 4%, las complicaciones (95.6 vs 65.7%, la disfunción renal (58.6 vs 31.4%, el embolismo mayor (60.8 vs 34%, los fenómenos microvasculares (43.4 vs 17.1% y la cirugía valvular (34.7 vs 11.4% ocurrieron significativamente en el Grupo 1 (pPatients with infective endocarditis (IE were studied to assess incidence, clinical features and mortality in a population with either persistent (PF or recurrent fever (RF during treatment. A sample of 81 patients was evaluated. Of these, 46 patients (56.8% had fever during treatment: 35 had PF and 16 had RF (Group 1. This group was compared with 35 patients with IE without fever (Group 2. Age, sex, in-hospital days, nosocomial acquisition, delay in diagnosis, and co-morbidities were similar among each group. The aortic and tricuspid valve compromise, and Staphylococcus aureus as etiologic agent were more frequent in Group 1 (although not significantly. However, the development of complications (95.6 vs. 65.7%, renal dysfunction (58.6 vs. 31.4%, major vessel embolization (60.8 vs. 34%, microvascular phenomena (43.4 vs. 17.1%, infections with MRSA (22.2 vs. 4% and valvular surgery (34.7 vs. 11.4% were significantly higher in Group 1(p<0.05. The most common causes of PF were microvascular phenomena (14

  6. Isolation and characterization of Staphylococcus aureus from raw cow milk in Bangladesh

    Directory of Open Access Journals (Sweden)

    Mueena Jahan

    2015-03-01

    Full Text Available The study was intended for identification and characterization of Staphylococcus aureus isolated from raw cow milk. A total of 47 milk samples were collected from Sheshmore, Shutiakhali and Bangladesh Agricultural University Dairy Farm, Mymensingh. Using bacteriological, biochemical and PCR-based identification schemes, 12 (25.53% isolates were confirmed as S. aureus. All the isolates showed β-hemolysis on 5% sheep blood agar. S. aureus specific nuc gene (target size 279-bp was amplified in the cases of all isolates. The isolates were found as resistant to Penicillin (100%, Erythromycin (75% and Amoxicillin (100%. On the other hand, the isolates were sensitive to Ciprofloxacin (83.33%, Oxacillin (100%, Cloxacillin (100% and Neomycin (100%. The isolated S. aureus showed increased resistance to broad spectrum antibiotic (e.g., Ciprofloxacin. As many people have a tendency to drink raw milk and raw milk products, there is high risk of S. aureus infection in human.

  7. Prolonged in vitro exposure of Staphylococcus aureus to germicidal teat dips.

    Science.gov (United States)

    Hogan, J S; Smith, K L

    1989-04-01

    Eight strains of Staphylococcus aureus were tested to determine if prolonged exposure to commercial teat dips could enhance bacterial tolerance to teat dips in vitro. All strains of S. aureus were serially plated 15 times on chemically defined agar medium containing sublethal concentrations of linear dodecyl benzene sulfonic acid, chlorhexidine, sodium hypochlorite, and iodophor teat dips. Growth responses of S. aureus to chlorhexidine, sodium hypochlorite, and iodophor were not affected by prolonged exposure to these teat dips. Isolates subcultured on agar containing .1% linear dodecyl benzene sulfonic acid teat dip subsequently had a greater mean growth response to .1% solution of the germicide than did controls subcultured on basal medium. Hemolytic patterns, tube coagulase, clumping factor, and protein A reactions of S. aureus were not altered by exposure to any of the teat dips tested. In general, prolonged exposure to commercial teat dips did not alter germicidal susceptibility of S. aureus. PMID:2745808

  8. Staphylococcus aureus can substitute double antibody in radio-immunoassay of LHRH

    International Nuclear Information System (INIS)

    The possibility of using protein-A containing Staphylococcus aureus in the separation of bound and free fractions in the radioimmunoassay (RIA) luteinzing hormone release hormone (LHRH) and its antibody has been explored by comparing it with the double antibody (DAB) method. While S. aureus method separation requires 15 min of incubation at room temperature and low speed centrifugation (1000 g. 10 min) for obtaining the pellet of the bounds phase, DAB takes overnight incubation at 40 and demands centrifugation at higher speed. S. aureus has affinity of binding to most mammalian IgGs and is thus amenable to use with many types of first antibody. DAB, on the other hand, is strictly species specific. Non-specific binding is low with S. aureus (below 5 percent). Thus S. aureus can easily replace DAB in RIAs with added advantages of speed universality, and low cost. (author)

  9. Dialysis catheter-related septicaemia--focus on Staphylococcus aureus septicaemia

    DEFF Research Database (Denmark)

    Nielsen, J; Ladefoged, S D; Kolmos, H J

    1998-01-01

    BACKGROUND: Dialysis catheters are a common cause of nosocomial septicaemia in haemodialysis units usually due to staphylococci, of which Staphylococcus aureus is the most pathogenic. In this study, the epidemiology and pathogenesis of dialysis catheter-related infections were studied, and methods....../67) of all catheter periods--84% of these were due to coagulase-negative staphylococci. CONCLUSIONS: Dialysis catheter-related S. aureus septicaemia was highly unlikely if the patient had not been carrying S. aureus in the nose or at the insertion site during the time the catheter was in place. The best...... predictor of dialysis catheter-related S. aureus septicaemia was a positive S. aureus culture from the insertion site. Positive catheter blood cultures unrelated to any clinical signs of septicaemia occurred in one-third of all catheter periods, and 84% of these were due to coagulase-negative staphylococci....

  10. Multilocus Sequence Typing And Antibiotic Resistance Of Staphylococcus Aureus Isolated From The Brazilian Dairy Industry

    DEFF Research Database (Denmark)

    Dittmann, Karen Kiesbye; Chaul, Luiza; Lee, Sarah;

    2015-01-01

    Staphylococcus aureus is a common cause of food poisoning due to enterotoxin production. This is particularly an issue in the dairy industry, where S. aureus can contaminate the product e.g. from raw milk or the handlers. In Brazil, soft cheese is mainly produced in small dairy plants where good...... hygiene practices can be limited. The aim of this study was to determine if Brazilian dairy plants were contaminated by S. aureus, and if any clones were persistent. Four dairy plants were sampled during 8 months (398 samples in total). S. aureus (n=66) was found in all the dairy plants...... presumptive methicillin-sensitive S. aureus. All of the isolates expressed hemolytic activity. The frequent isolation of CC1 strains in Brazilian dairy plants indicates, despite antibiotic sensitivity, a potential health risk to the human consumer....

  11. Haematogenous Staphylococcus aureus meningitis. A 10-year nationwide study of 96 consecutive cases

    DEFF Research Database (Denmark)

    Pedersen, Michael; Benfield, Thomas L; Skinhoej, Peter;

    2006-01-01

    BACKGROUND: Haematogenous Staphylococcus aureus meningitis is rare but associated with high mortality. Knowledge about the disease is still limited. The objective of this study was to evaluate demographic and clinical prognostic features of bacteraemic S. aureus meningitis. METHODS: Nationwide...... surveillance in Denmark from 1991 to 2000 with clinical and bacteriological data. Risks of death were estimated by Cox proportional hazards regression analysis. RESULTS: Among 12480 cases of S. aureus bacteraemia/sepsis, we identified 96 cases of non-surgical bacteraemic S. aureus meningitis (0.8%). Incidence...... > or = 4) (HR, 2.14; CI, 1.09 to 4.19) remained independent predictors of mortality. CONCLUSION: The incidence, but not mortality of bacteraemic S. aureus meningitis decreased during the study period. Co morbidity and critical illness were independent predictors of a poor outcome....

  12. Staphylococcus aureus infections: transmission within households and the community.

    Science.gov (United States)

    Knox, Justin; Uhlemann, Anne-Catrin; Lowy, Franklin D

    2015-07-01

    Staphylococcus aureus, both methicillin susceptible and resistant, are now major community-based pathogens worldwide. The basis for this is multifactorial and includes the emergence of epidemic clones with enhanced virulence, antibiotic resistance, colonization potential, or transmissibility. Household reservoirs of these unique strains are crucial to their success as community-based pathogens. Staphylococci become resident in households, either as colonizers or environmental contaminants, increasing the risk for recurrent infections. Interactions of household members with others in different households or at community sites, including schools and daycare facilities, have a critical role in the ability of these strains to become endemic. Colonization density at these sites appears to have an important role in facilitating transmission. The integration of research tools, including whole-genome sequencing (WGS), mathematical modeling, and social network analysis, has provided additional insight into the transmission dynamics of these strains. Thus far, interventions designed to reduce recurrent infections among household members have had limited success, likely due to the multiplicity of potential sources for recolonization. The development of better strategies to reduce the number of household-based infections will depend on greater insight into the different factors that contribute to the success of these uniquely successful epidemic clones of S. aureus. PMID:25864883

  13. Antimicrobial activity of essential oils against Staphylococcus aureus biofilms.

    Science.gov (United States)

    Vázquez-Sánchez, Daniel; Cabo, Marta L; Rodríguez-Herrera, Juan J

    2015-12-01

    The present study was aimed to evaluate the potential of essential oils to remove the foodborne pathogen Staphylococcus aureus from food-processing facilities. The effectiveness of 19 essential oils against planktonic cells of S. aureus was firstly assessed by minimal inhibitory concentration. Planktonic cells showed a wide variability in resistance to essential oils, with thyme oil as the most effective, followed by lemongrass oil and then vetiver oil. The eight essential oils most effective against planktonic cells were subsequently tested against 48-h-old biofilms formed on stainless steel. All essential oils reduced significantly (p < 0.01) the number of viable biofilm cells, but none of them could remove biofilms completely. Thyme and patchouli oils were the most effective, but high concentrations were needed to achieve logarithmic reductions over 4 log CFU/cm(2) after 30 min exposure. Alternatively, the use of sub-lethal doses of thyme oil allowed to slow down biofilm formation and to enhance the efficiency of thyme oil and benzalkonium chloride against biofilms. However, some cellular adaptation to thyme oil was detected. Therefore, essential oil-based treatments should be based on the rotation and combination of different essential oils or with other biocides to prevent the emergence of antimicrobial-resistant strains. PMID:25280938

  14. Excreted Cytoplasmic Proteins Contribute to Pathogenicity in Staphylococcus aureus.

    Science.gov (United States)

    Ebner, Patrick; Rinker, Janina; Nguyen, Minh Thu; Popella, Peter; Nega, Mulugeta; Luqman, Arif; Schittek, Birgit; Di Marco, Moreno; Stevanovic, Stefan; Götz, Friedrich

    2016-06-01

    Excretion of cytoplasmic proteins in pro- and eukaryotes, also referred to as "nonclassical protein export," is a well-known phenomenon. However, comparatively little is known about the role of the excreted proteins in relation to pathogenicity. Here, the impact of two excreted glycolytic enzymes, aldolase (FbaA) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), on pathogenicity was investigated in Staphylococcus aureus Both enzymes bound to certain host matrix proteins and enhanced adherence of the bacterial cells to host cells but caused a decrease in host cell invasion. FbaA and GAPDH also bound to the cell surfaces of staphylococcal cells by interaction with the major autolysin, Atl, that is involved in host cell internalization. Surprisingly, FbaA showed high cytotoxicity to both MonoMac 6 (MM6) and HaCaT cells, while GAPDH was cytotoxic only for MM6 cells. Finally, the contribution of external FbaA and GAPDH to S. aureus pathogenicity was confirmed in an insect infection model. PMID:27001537

  15. Expression and crystallization of DsbA from Staphylococcus aureus

    International Nuclear Information System (INIS)

    Free-interface diffusion crystallization chips were used to identify crystallization conditions for S. aureus DsbA, representing the first Gram-positive DsbA to be crystallized. Native and selenomethionine-derivative crystals diffracted to 2.1 and 2.4 Å resolution, respectively. Bacterial Dsb proteins catalyse the in vivo formation of disulfide bonds, a critical step in the stability and activity of many proteins. Most studies on Dsb proteins have focused on Gram-negative bacteria and thus the process of oxidative folding in Gram-positive bacteria is poorly understood. To help elucidate this process in Gram-positive bacteria, DsbA from Staphylococcus aureus (SaDsbA) has been focused on. Here, the expression, purification, crystallization and preliminary diffraction analysis of SaDsbA are reported. SaDsbA crystals diffract to a resolution limit of 2.1 Å and belong to the hexagonal space group P65 or P61, with unit-cell parameters a = b = 72.1, c = 92.1 Å and one molecule in the asymmetric unit (64% solvent content)

  16. Staphylococcus aureus ampicillin-resistant from the odontological clinic environment.

    Science.gov (United States)

    Bernardo, Wagner Luis de Carvalho; Boriollo, Marcelo Fabiano Gomes; Gonçalves, Reginaldo Bruno; Höfling, José Francisco

    2005-01-01

    The aim of this research was to evaluate the prevalence of Staphylococcus spp. and S. aureus in the odontological clinic environment (air), their production of beta-lactamase and antibacterial susceptibility to the major antibiotics utilized in medical particle. During 12 months of samples collect were isolated 9775 CFU by MSA medium suggesting a high amount of Staphylococcus spp. in the clinic environment which can appear through aerosols. A total of 3149 colonies (32.2%) were suggestive of pathogenic staphylococci. Gram coloration, catalase test, colony-mallow growing on chromogenic medium, and coagulase test confirmed the identity of 44 (0.45%) S. aureus isolates. Of these, 35 isolates (79.5%) showed production of beta-lactamase by Cefinase discs and resistance to ampicillin, erythromycin (7 isolates) and tetracycline (1 isolate) suggesting the existence of multiresistant isolates. The evaluation of the oxacillin MIC by Etest assays showed susceptibility patterns suggesting the inexistence of the mecA gene in chromosomal DNA. These results point out to the need of a larger knowledge on the contamination means and propagation of this microorganism into the odontological clinic. PMID:15729470

  17. AKTIVITAS ANTIBAKTERI GETAH PEPAYA KERING TERHADAP Staphylococcus aureus PADA DANGKE [Antibacterial Activity of Dried Papaya Latex toward Staphylococcus aureus in Dangke

    Directory of Open Access Journals (Sweden)

    Rifah Hestyani Arum

    2014-06-01

    Full Text Available Dangke is a traditional milk curd product, made by coagulation of milk using fresh papaya latex. This product is usually kept at room temperature (27-30ºC until consumption. Dried papaya latex was used in this study to produce dangke, and its effect to S. aureus was determined by direct contact in TSB and dangke. Fresh papaya latex was dried using vacuum oven at 50-55ºC for 22 hours. Dried papaya latex at a concentration of 2.7x10-3 g/100 mL could reduce S. aureus approximately 1 log CFU/mL in TSB after 24 hours. Dried papaya latex and papain could maintain the S. aureus number in dangke within 24 hours storage at room temperature. The antibacterial activity of non-proteolytic compound of papaya latex, i.e ethanolic extract of papaya latex was determined by macrodilution method, resulted an the MIC90 of 8 mg/mL. The cell membrane leakage after exposure was detected by measuring the optical density of bacterial supernatant at 260 nm. The result showed that exposure to increasing antibacterial concentration resulted in increasing of optical density of S. aureus supernatant, indicating that the antibacterial caused the S. aureus membrane leakage. Fluorescence microscopy imaging showed that S. aureus exposure to antibacterial caused membrane leakage thus gave Propidium Iodide (PI chance to penetrate into the cell, as indicated by changing of fluorescence color from green to red.

  18. Sepse por Staphylococus aureus resistente à meticilina adquirida na comunidade no sul do Brasil Sepsis due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil

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    Luciane Cristina Gelatti

    2009-08-01

    Full Text Available Staphylococcus aureus resistente à meticilina foi inicialmente descrito como um típico microrganismo adquirido em infecções nosocomiais. No entanto, nos últimos anos Staphylococcus aureus resistente à meticilina adquirido na comunidade é causa de infecções de pele e tecidos moles, mas infecções graves como pneumonia e sepse podem ocorrer. Este relato descreve um caso de sepse em criança, complicado com pneumonia secundária a lesão em partes moles por Staphylococcus aureus resistente à meticilina adquirido na comunidade no Sul do Brasil. O paciente foi atendido em Unidade de Emergência com história de ferimento provocado por trauma em membro inferior que evoluiu para celulite, pneumonia e sepse.Methicillin-resistant Staphylococcus aureus was initially described as a typical microorganism acquired in nosocomial infections. However, over recent years, community-acquired methicillin-resistant Staphylococcus aureus has been a cause of skin and soft-tissue infections. Serious infections such as pneumonia and sepsis can also occur. This report describes a case of sepsis in a child that was complicated by pneumonia secondary to soft tissue lesions that were due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil. The patient was attended at the Emergency Unit with a history of injury caused by lower-limb trauma that evolved to cellulitis, pneumonia and sepsis.

  19. Close association between oropharyngeal and rhinopharyngeal colonization with Staphylococcus aureus - clues to new insight of MRSA colonization of the oropharynx

    DEFF Research Database (Denmark)

    Petersen, I S; Larsen, P L; Brandelev, B L;

    2013-01-01

    This study provides data on prevalence of Staphylococcus aureus in oropharynx, rhinopharynx and vestibulum nasi. Specimens were taken from these three pharyngeal sites in 346 patients and analysed for S. aureus. Abnormal pharyngeal findings and patient histories were recorded. S. aureus was found...

  20. Bactericidal activity of the food color additive Phloxine B against Staphylococcus aureus and other food borne microbial pathogens

    Science.gov (United States)

    The spread of antibiotic resistance among Staphylococcus aureus strains requires the development of new anti S. aureus agents. The objective of this study was evaluating the antimicrobial activity of the food color additive Phloxine B against S. aureus and other food microbial pathogens. Our result ...

  1. Potential Clindamycin Resistance in Clindamycin-Susceptible, Erythromycin-Resistant Staphylococcus aureus: Report of a Clinical Failure

    OpenAIRE

    Levin, Todd P.; Suh, Byungse; Axelrod, Peter; Truant, Allan L.; Fekete, Thomas

    2005-01-01

    The erm gene product confers clindamycin resistance on Staphylococcus aureus. We report a clindamycin clinical failure where resistance developed on therapy in a D-test-positive strain. D tests of 91 clindamycin-susceptible, erythromycin-resistant S. aureus isolates showed that 68% of methicillin-susceptible and 12.3% of methicillin-resistant S. aureus strains were D-test positive.

  2. Nosocomial and Community-Acquired Staphylococcus Aureus Bacterimias from 1980 to 1993: Impact of Intravascular Devices and Methicillin Resistance

    NARCIS (Netherlands)

    J.P. Steinberg; C.C. Clarke; B.O. Hackman

    1996-01-01

    textabstractThe rate of nosocomial bacteremia due to Staphylococcus aureus has increased over the past decade, but trends in community-acquired S. aureus bacteremia are less certain. This hospital-based observational study compares nosocomial and community-acquired S. aureus bacteremias during 1980-

  3. Minimum inhibitory concentration of ciprofloxacin in combination with hexahydroquinoline derivatives against Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    F Amin Harati

    2012-12-01

    Full Text Available Background: Staphylococcus aureus is the most common pathogen responsible for skin and soft tissue infections worldwide. Methicillin-resistant S. aureus is a major cause of both nosocomial and community acquired infections. The emergence of antimicrobial-resistant S. aureus is of global concern. Fluoroquinolone antimicrobials including ciprofloxacin, levofloxacin, and moxifloxacin are used to treat skin and soft tissue infections due to S. aureus. Emergence of ciprofloxacin resistance has increased in community acquired methicillin-resistant S. aureus strains. The aim of this study was to evaluate the minimum inhibitory concentration of ciprofloxacin and hexahydroquino-line derivatives against methicillin- and ciprofloxacin-resistant S. aureus.Methods: Identification of S. aureus was performed by routine microbiological tests in the Department of Pathobiology in Winter 2012. The susceptibility of S. aureus strains to both methicillin and ciprofloxacin was examined by the Kirby-Bauer disk-diffusion method. The minimum inhibitory concentration of ciprofloxacin, hexahydroquinoline derivatives and their combination were separately determined by broth microdilution method against methicillin- and ciprofloxacin-resistant S. aureus.Results: The minimum inhibitory concentration of ciprofloxacin decreased in the presence of hexahydroquinolinein derivatives in comparison with ciprofloxacin alone.Conclusion: This study showed that hexahydroquinoline derivatives enhance the antibacterial effect of ciprofloxacin against methicillin- and ciprofloxacin-resistant S. aureus. Therefore, these derivatives could be used as inhibitors of antibiotic resistance in combination therapies. This enhancement may be related to the inhibitory effect of hexahydroquinoline derivatives on the expression of antibiotic efflux pump in the bacteria. However, the structural features of a fluoroquinolone that determine whether it is affected by efflux transporters are not fully

  4. Prevalence and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus in ocular infections

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    Maria Eugenia Vola

    2013-12-01

    Full Text Available PURPOSE: To study the prevalence of methicillin-resistant Staphylococcus aureus among S. aureus ocular infections in a tertiary health center in Brazil and compare antibiotic susceptibility patterns between MRSA and methicillin-susceptible S. aureus isolates. METHODS: Electronic records from the ocular microbiology laboratory of the Universidade Federal de São Paulo were retrospectively reviewed. During a 10-year period (between January 2000 and December 2009 all conjunctivitis, keratitis, and endophthalmitis cases with a positive culture for S. aureus were identified. Antibiotic susceptibility was determined using the Kirby-Bauer disk diffusion method. RESULTS: Five hundred sixty-six S. aureus isolates were identified; of those, 56 (9.9% were resistant to methicillin. Throughout the 10-year period, Staphylococcus aureus showed a significant increasing trend from 7.55% to 16.18% among overall S. aurues infections (p=0.001 and from 3.7% to 13.16% in conjunctivitis (p=0.001. Conversely, we did not observe the same trend among those with keratitis (p=0.38. Staphylococcus aureus isolates showed higher resistance rates to tobramycin, gentamicin, ciprofloxacin, gatifloxacin, and moxifloxacin when compared with S. aureus isolates (p< 0.001. All cases were susceptible to vancomycin. CONCLUSION: We observed an increasing trend in the overall prevalence of Staphylococcus aureus ocular infections and statistically significant higher resistance rates to commonly used antibiotics compared to Staphylococcus aureus. Our data supports the need for constant bacterial surveillance and should be taken into consideration before initiating empiric treatment of ocular infections.

  5. Extended Staphylococcus aureus persistence in cystic fibrosis is associated with bacterial adaptation.

    Science.gov (United States)

    Hirschhausen, Nina; Block, Desiree; Bianconi, Irene; Bragonzi, Alessandra; Birtel, Johannes; Lee, Jean C; Dübbers, Angelika; Küster, Peter; Kahl, Janina; Peters, Georg; Kahl, Barbara C

    2013-12-01

    Staphylococcus aureus often persists in the airways of cystic fibrosis (CF) patients. There is only limited knowledge about bacterial persistence in and adaptation to this new ecological environment. Therefore, we used S. aureus isolates from a unique strain collection, in which all S. aureus isolates recovered from CF patients from two CF centers were stored from more than 150 CF patients for more than a decade. S. aureus early and late isolates from 71 CF patients with long-term staphylococcal colonization of the airways (≥ 5 years) were preselected by genotyping of agr and cap. Identical pairs were subjected to spa-typing and MLST. S. aureus strain pairs of individual patients with the same or closely related spa-type and identical MLST were compared for adaptive changes in important phenotypic and virulence traits. The virulence of three S. aureus strain pairs (early and late isolates) was analyzed in a murine chronic pneumonia model. Strain pairs of 29 individual patients belonged to the same MLST and same or closely related spa-types. The mean persistence of the same clone of S. aureus in 29 CF patients was 8.25 years. Late compared to early isolates were altered in production of capsule (48%), hemolysis (45%), biofilm formation (41%), as well as antibiotic susceptibility (41%), cytotoxicity (34%), colony size (28%), and spa-type (17%). Adaptive changes positively correlated with the length of S. aureus persistence. For seven patients from whom the initial colonizing isolate was recovered, staphylococcal adaptation was most apparent, with capsule production being reduced in five of seven late isolates. In a mouse chronic pneumonia model, all tested isolates strongly induced chronic pneumonia with severe lesions in bronchi and pulmonary parenchyma. Adaptive changes in S. aureus accumulated with the length of persistence in the CF airways, but differed in patients infected with the same S. aureus clonal lineage indicating that individual host factors have an

  6. Identification of single nucleotide polymorphisms associated with hyperproduction of alpha-toxin in Staphylococcus aureus.

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    Xudong Liang

    Full Text Available The virulence factor α-toxin (hla is needed by Staphylococcus aureus in order to cause infections in both animals and humans. Although the complicated regulation of hla expression has been well studied in human S. aureus isolates, the mechanisms of of hla regulation in bovine S. aureus isolates remain undefined. In this study, we found that many bovine S. aureus isolates, including the RF122 strain, generate dramatic amounts of α-toxin in vitro compared with human clinical S. aureus isolates, including MRSA WCUH29 and MRSA USA300. To elucidate potential regulatory mechanisms, we analyzed the hla promoter regions and identified predominant single nucleotide polymorphisms (SNPs at positions -376, -483, and -484 from the start codon in α-toxin hyper-producing isolates. Using site-directed mutagenesis and hla promoter-gfp-luxABCDE dual reporter approaches, we demonstrated that the SNPs contribute to the differential control of hla expression among bovine and human S. aureus isolates. Using a DNA affinity assay, gel-shift assays and a null mutant, we identified and revealed that an hla positive regulator, SarZ, contributes to the involvement of the SNPs in mediating hla expression. In addition, we found that the bovine S. aureus isolate RF122 exhibits higher transcription levels of hla positive regulators, including agrA, saeR, arlR and sarZ, but a lower expression level of hla repressor rot compared to the human S. aureus isolate WCUH29. Our results indicate α-toxin hyperproduction in bovine S. aureus is a multifactorial process, influenced at both the genomic and transcriptional levels. Moreover, the identification of predominant SNPs in the hla promoter region may provide a novel method for genotyping the S. aureus isolates.

  7. Evaluating Susceptibility to Commercial Fungicide of Endophytic Fungi Isolated from Roses (Rosa hybrida Evaluación de la susceptibilidad de hongos endófitos aislados de rosa (rosa hybrida a fungicidas comerciales

    Directory of Open Access Journals (Sweden)

    Restrepo Silvia

    2007-07-01

    ófitos.    En este trabajo se evaluó la susceptibilidad de hongos endófitos aislados de Rosa hybrida a fungicidas utilizados comercialmente en el control de patógenos en el cultivo de rosa. Esto se realizó in vitro, mezclando diferentes concentraciones de fungicidas con medios estándares en el crecimiento de hongos endófitos y midiendo diariamente su crecimiento.  La susceptibilidad de Botrytis cinerea (Cepa 3015, uno de los más importantes patógenos que afecta el cultivo de rosas en Colombia, se analizó de la misma forma. El 45,45% de los hongos endófitos evaluados demostraron susceptibilidad de crecimiento con grados de sensibilidad desde no sensibles (³73,75% hasta regularmente sensibles (³48,75% - 61,25% en las concentraciones evaluadas principalmente en fungicidas como boscalid, captan, iprodione y pyrimethanil. En el caso de fungicidas como carboxin más thiram, fludioxonil más ciprodinil, y prochloraz, se observaron grados de susceptibilidad de alta sensibilidad (23,75%, inhibiendo totalmente el crecimiento de los hongos endófitos evaluados. En B. cinerea (Cepa 3015 se observó alta susceptibilidad a pyrimethanil, carboxin más thiram, fludioxonil más ciprodinil, y prochloraz. Aunque los controles de B. cinerea tuvieron mayores crecimientos, la mayoría de los crecimientos de los hongos endófitos evaluados en los medios enmendados en las dos concentraciones fueron superiores a los de este patógeno. El rango de susceptibilidad de hongos endófitos como las cepas 3002, 3003, 3004, 3005 y 3006 bajo los parámetros de análisis de este experimento, muestra su selección como hongos promisorios para programas de manejo integrado de plagas y enfermedades, teniendo en cuenta el momento, la frecuencia y la dosis de aplicación tanto de los fungicidas como de los hongos endófitos empleados.

  8. Surgimiento y diseminación de Staphylococcus aureus meticilinorresistente Staphylococcus aureus methicillin-resistant: emergence and dissemination

    Directory of Open Access Journals (Sweden)

    Maria Elena Velázquez-Meza

    2005-10-01

    Full Text Available Las infecciones nosocomiales ocasionadas por cepas de Staphylococcus aureus meticilinorresistentes (SAMR son un problema de salud importante en todo el mundo. Este microorganismo produce una gran variedad de infecciones incluyendo osteomielitis, endocarditis invasora, artritis séptica y septicemia. La multirresistencia es un factor que influye en la persistencia de los SAMR dentro del ámbito hospitalario. La introducción de técnicas de tipificación molecular dentro de las investigaciones epidemiológicas ha provisto nuevas herramientas para conocer el origen y las vías de diseminación de este microorganismo. Una de las conclusiones importantes que han surgido de este tipo de estudios es que un número pequeño de clonas son las responsables de las infecciones estafilocócicas en todo el mundo.Nosocomial infections due to methicillin-resistant Staphylococcus aureus (MRSA is an important health problem worldwide. This microorganism causes a variety of clinical infections, including osteomyelitis, invasive endocarditis, septic arthritis and septicemia. Antimicrobial resistance is a factor that influences the persistence of MRSA in the hospital environment. The introduction of molecular typing techniques in epidemiological investigations has provided new tools for identifying the microorganism's origin and routes of dissemination. One of the most important conclusions that have resulted from these types of studies is that a small number of clones are responsible for most of the staphylococcal infections throughout the world.

  9. Antimicrobial Resistance, Biofilm Formation and mecA Characterization of Methicillin-Susceptible S. aureus and Non-S. aureus of Beef Meat Origin in Egypt.

    Science.gov (United States)

    Osman, Kamelia M; Amer, Aziza M; Badr, Jihan M; Helmy, Nashwa M; Elhelw, Rehab A; Orabi, Ahmed; Bakry, Magdy; Saad, Aalaa S A

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) have been found in various farm animal species throughout the world. Yet, methicillin-susceptible S. aureus (MSSA), methicillin-susceptible non-S. aureus (MS-NSA), and methicillin-resistant non-S. aureus (MR-NSA) were not investigated. Therefore, we persued to determine the diversity in their phenotypic virulence assay, phenotypic antimicrobial resistance profile and molecular characterization in one of the food chains in Egypt. Samples were collected during 2013 from beef meat at retail. Twenty seven isolates comprising five species (S. hyicus, S. aureus, S. schleiferi subsp. coagulans, S. intermedius, and S. lentus) were characterized for their antibiotic resistance phenotypic profile and antibiotic resistance genes (mecA, cfr, gyrA, gyrB, and grlA). Out of the 27 Staphylococcus isolates only one isolate was resistant to the 12 antibiotics representing nine classes. Raw beef meat sold across the Great Cairo zone, contains 66.7% of MRS, with highest prevalence was reported in S. aureus (66.7%), while the MRS non-S. aureus strains constituted 66.7% from which S. hyicus (60%), S. intermedius (33.3%), S. schleiferi subsp. coagulans (100%), and S. lentus (100%) were MRS. Seven S. aureus, six S. hyicus, four S. schleiferi subsp. coagulans, three S. intermedius, and one S. lentus isolates although being resistant to oxacillin yet, 11/27 (40.7%) carried the mecA gene. At the same time, the cfr gene was present in 2 of the nine S. aureus isolates, and totally undetectable in S. hyicus, S. schleiferi subsp. coagulans, S. intermedius, and S. lentus. Although, global researches largely focused into MRSA and MR-NSA in animals on pigs, the analysis of our results stipulates, that buffaloes and cattle could be MRSA dispersers and that this theme is not specific to pigs. Detection of MSSA virulence determinants is a must, as although oxacillin resistance may be absent yet, the MSSA may carry the virulence determinants which

  10. Actividad antimicrobiana del OLEOZON® sobre Staphylococcus aureus y Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    V. Curtiellas

    2005-01-01

    Full Text Available La actividad antimicrobiana de los aceites vegetales ozonizados suele atribuirse a la acción de los compuestos peroxídicos presentes en los mismos sobre las biomoléculas más sensibles al ataque oxidante, como son los lípidos insaturados y las proteínas que presentan grupos sulfidrilos (SH. Con el objetivo de caracterizar la actividad in vitro del aceite de girasol ozonizado, OLEOZON®, se realizó un estudio empleando las cepas S. aureus ATCC 25923 y P. aeruginosa ATCC 27853. Se determinaron las concentraciones inhibitorias mínimas y las concentraciones bactericidas mínimas de acuerdo a lo establecido por el comité nacional para normas de laboratorio clínico (EE.UU, 2000. Se aplicó Tween 80 y ultrasonido para lograr una emulsión estable entre el aceite y el medio de cultivo. Se realizó un estudio cinético de inactivación empleando una concentración del agente antimicrobiano de 89 mg/mL y tiempos de contacto de 1, 3, 10 y 30 minutos. En paralelo a estos estudios se determinaron las variaciones en la concentración de los grupos sulfidrilos totales mediante lectura a 412 nm del compuesto cromógeno resultante de la reacción con DTNB, (5,5'- ditiobis (2- ácido nitro benzoico. Los valores de las concentraciones inhibitorias mínimas y bactericidas mínimas resultaron menores en S. aureus que en P. Aeruginosa, Mientras que las curvas de inactivación siguieron en ambos casos una cinética de primer orden respecto al número de viables. La determinación de la concentración de los grupos SH totales muestra una disminución significativa para ambos microorganismos desde el primer minuto de contacto con el OLEOZON®, la que es más acentuada en el caso de S. aureus, lo que demuestra que la oxidación de los grupos SH constituye uno de los daños primarios asociados al efecto letal de este medicamento.

  11. Genomic organization of a vancomycin-resistant staphylococcus aureus

    International Nuclear Information System (INIS)

    Objective: To study the genomic organization of vancomycin resistance in a local isolate of vancomycin resistant Staphylococcus aureus (VRSA). Study Design: Experimental study. Place and Duration of Study: Department of Microbiology, University of Karachi, January 2008 through December 2010. Methodology: A vancomycin-resistant Staphylococcus aureus (VRSA-CP2) isolate (MIC 16 mu g/ml) was isolated from a local hospital of Karachi. Species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc gene. The vancomycin MIC was re-confirmed by E-test. For the genetic determination of vancomycin resistance, in-vitro amplification of vanA cassette was performed by using plasmid DNA of CP2, CP2's transformant as template on MWG Thermo-Cycler. Amplified products of vanR, vanS, vanH, vanA, vanY, orf2, orf1D, orf2E, orf-Rev and IS element genes were subjected to Sanger's electrophoresis based sequence determination using specific primers. The Basic Local Alignment Search Tool (BLAST) algorithm was used to identify sequences in GenBank with similarities to the vanA cassette genes. Results: The vancomycin-resistant isolate CP2 was found to be resistant to oxacillin, chloramphenicol, erythromycin, rifampicin, gentamicin, tetracycline and ciprofloxacin, as well. The isolate CP2 revealed four bands: one of large molecular size approx 56.4 kb and three of small size approx 6.5 kb, approx 6.1 kb and approx 1.5 kb by agarose gel electrophoresis indicating the presence of 3 plasmids. The plasmid DNA of isolate CP2 was analyzed by PCR for the presence of the van cassettes with each of the vanA , vanB and vanC specific primers. It carried vanA cassette, which comprises of vanR, vanS, vanH, vanA, vanY, and orf2. The vanA cassette of isolate CP2 also carried an insertion element (IS). However, it did not show the PCR product for orf1. Vancomycin resistance was successfully transferred from the donor CP2 to a vancomycin-sensitive recipient S

  12. Active immunization with an octa-valent Staphylococcus aureus antigen mixture in models of S. aureus bacteremia and skin infection in mice.

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    Sanne van den Berg

    Full Text Available Proteomic studies with different Staphylococcus aureus isolates have shown that the cell surface-exposed and secreted proteins IsaA, LytM, Nuc, the propeptide of Atl (pro-Atl and four phenol-soluble modulins α (PSMα are invariantly produced by this pathogen. Therefore the present study was aimed at investigating whether these proteins can be used for active immunization against S. aureus infection in mouse models of bacteremia and skin infection. To this end, recombinant His-tagged fusions of IsaA, LytM, Nuc and pro-Atl were isolated from Lactococcus lactis or Escherichia coli, while the PSMα1-4 peptides were chemically synthesized. Importantly, patients colonized by S. aureus showed significant immunoglobulin G (IgG responses against all eight antigens. BALB/cBYJ mice were immunized subcutaneously with a mixture of the antigens at day one (5 μg each, and boosted twice (25 μg of each antigen with 28 days interval. This resulted in high IgG responses against all antigens although the response against pro-Atl was around one log lower compared to the other antigens. Compared to placebo-immunized mice, immunization with the octa-valent antigen mixture did not reduce the S. aureus isolate P load in blood, lungs, spleen, liver, and kidneys in a bacteremia model in which the animals were challenged for 14 days with a primary load of 3 × 10(5 CFU. Discomfort scores and animal survival rates over 14 days did not differ between immunized mice and placebo-immunized mice upon bacteremia with S. aureus USA300 (6 × 10(5 CFU. In addition, this immunization did not reduce the S. aureus isolate P load in mice with skin infection. These results show that the target antigens are immunogenic in both humans and mice, but in the used animal models do not result in protection against S. aureus infection.

  13. Staphylococcus aureus produces membrane-derived vesicles that induce host cell death.

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    Mamata Gurung

    Full Text Available Gram-negative bacteria produce outer membrane vesicles that play a role in the delivery of virulence factors to host cells. However, little is known about the membrane-derived vesicles (MVs produced by gram-positive bacteria. The present study examined the production of MVs from Staphylococcus aureus and investigated the delivery of MVs to host cells and subsequent cytotoxicity. Four S. aureus strains tested, two type strains and two clinical isolates, produced spherical nanovesicles during in vitro culture. MVs were also produced during in vivo infection of a clinical S. aureus isolate in a mouse pneumonia model. Proteomic analysis showed that 143 different proteins were identified in the S. aureus-derived MVs. S. aureus MVs were interacted with the plasma membrane of host cells via a cholesterol-rich membrane microdomain and then delivered their component protein A to host cells within 30 min. Intact S. aureus MVs induced apoptosis of HEp-2 cells in a dose-dependent manner, whereas lysed MVs neither delivered their component into the cytosol of host cells nor induced cytotoxicity. In conclusion, this study is the first report that S. aureus MVs are an important vehicle for delivery of bacterial effector molecules to host cells.

  14. High-resolution subtyping of Staphylococcus aureus strains by means of Fourier-transform infrared spectroscopy.

    Science.gov (United States)

    Johler, Sophia; Stephan, Roger; Althaus, Denise; Ehling-Schulz, Monika; Grunert, Tom

    2016-05-01

    Staphylococcus aureus causes a variety of serious illnesses in humans and animals. Subtyping of S. aureus isolates plays a crucial role in epidemiological investigations. Metabolic fingerprinting by Fourier-transform infrared (FTIR) spectroscopy is commonly used to identify microbes at species as well as subspecies level. In this study, we aimed to assess the suitability of FTIR spectroscopy as a tool for S. aureus subtyping. To this end, we compared the subtyping performance of FTIR spectroscopy to other subtyping methods such as pulsed field gel electrophoresis (PFGE) and spa typing in a blinded experimental setup and investigated the ability of FTIR spectroscopy for identifying S. aureus clonal complexes (CC). A total of 70 S. aureus strains from human, animal, and food sources were selected, for which clonal complexes and a unique virulence and resistance gene pattern had been determined by DNA microarray analysis. FTIR spectral analysis resulted in high discriminatory power similar as obtained by spa typing and PFGE. High directional concordance was found between FTIR spectroscopy based subtypes and capsular polysaccharide expression detected by FTIR spectroscopy and the cap specific locus, reflecting strain specific expression of capsular polysaccharides and/or other surface glycopolymers, such as wall teichoic acid, peptidoglycane, and lipoteichoic acid. Supervised chemometrics showed only limited possibilities for differentiation of S. aureus CC by FTIR spectroscopy with the exception of CC45 and CC705. In conclusion, FTIR spectroscopy represents a valuable tool for S. aureus subtyping, which complements current molecular and proteomic strain typing. PMID:27021524

  15. Protease inhibitors decrease IgG shedding from Staphylococcus aureus, increasing complement activation and phagocytosis efficiency.

    Science.gov (United States)

    Fernandez Falcon, Maria F; Echague, Charlene G; Hair, Pamela S; Nyalwidhe, Julius O; Cunnion, Kenji M

    2011-10-01

    Staphylococcus aureus is a major pathogen for immunologically intact humans and its pathogenesis is a model system for evasion of host defences. Antibodies and complement are essential elements of the humoral immune system for prevention and control of S. aureus infections. The specific hypothesis for the proposed research is that S. aureus modifies humoral host defences by cleaving IgG that has bound to the bacterial surface, thereby inhibiting opsonophagocytosis. S. aureus was coated with pooled, purified human IgG and assayed for the shedding of cleaved IgG fragments using ELISA and Western blot analysis. Surface-bound IgG was shed efficiently from S. aureus in the absence of host blood proteins. Broad-spectrum protease inhibitors prevented cleavage of IgG from the S. aureus surface, suggesting that staphylococcal proteases are responsible for IgG cleavage. Serine protease inhibitors and cysteine protease inhibitors decreased the cleavage of surface-bound IgG; however, a metalloprotease inhibitor had no effect. Using protease inhibitors to prevent the cleavage of surface-bound IgG increased the binding of complement C3 fragments on the surface of S. aureus, increased the association with human neutrophils and increased phagocytosis by human neutrophils. PMID:21636671

  16. Population structure and antimicrobial profile of Staphylococcus aureus strains associated with bovine mastitis in China.

    Science.gov (United States)

    Zhang, Lili; Li, Yuchen; Bao, Hongduo; Wei, Ruicheng; Zhou, Yan; Zhang, Hui; Wang, Ran

    2016-08-01

    Staphylococcus aureus is a significant bacterial pathogen associated with bovine mastitis. The aim of the present study was to investigate and characterize of S. aureus strains isolated from the milk of cows suffering from mastitis in the mid-east of China. Among the 200 milk samples analyzed, 58 were positive for S. aureus, of these isolates, 11 isolates were methicillin-resistant Staphylococcus aureus (MRSA). All of the 58 S. aureus strains were classified in agr group I, while seven different sequence type (ST) patterns were identified and among them the most common was ST630 followed by ST188. All of the S. aureus isolates belonging to ST630 were resistant to more than four antimicrobials, and 22.2% of isolates belonging to ST188 were resistant to eight antimicrobials. Interestingly, while strong biofilm producers demonstrated higher resistance to multiple antimicrobials, they exhibited lower intracellular survival rates. The results of this study illustrated the distribution, antimicrobial susceptibility profiles, genotype, and the ability of biofilm production and mammary epithelial cells invasion of these S. aureus isolates. This study can provide the basis for the development of a disease prevention program in dairy farms to reduce the potential risk in both animal and human health. PMID:27265679

  17. Phage sensitivity and prophage carriage in Staphylococcus aureus isolated from foods in Spain and New Zealand.

    Science.gov (United States)

    Gutiérrez, Diana; Rodríguez-Rubio, Lorena; García, Pilar; Billington, Craig; Premarante, Aruni; Rodríguez, Ana; Martínez, Beatriz

    2016-08-01

    Bacteriophages (phages) are a promising tool for the biocontrol of pathogenic bacteria, including those contaminating food products and causing infectious diseases. However, the success of phage preparations is limited by the host ranges of their constituent phages. The phage resistance/sensitivity profile of eighty seven Staphylococcus aureus strains isolated in Spain and New Zealand from dairy, meat and seafood sources was determined for six phages (Φ11, K, ΦH5, ΦA72, CAPSa1 and CAPSa3). Most of the S. aureus strains were sensitive to phage K (Myoviridae) and CAPSa1 (Siphoviridae) regardless of their origin. There was a higher sensitivity of New Zealand S. aureus strains to phages isolated from both Spain (ΦH5 and ΦA72) and New Zealand (CAPSa1 and CAPSa3). Spanish phages had a higher infectivity on S. aureus strains of Spanish dairy origin, while Spanish strains isolated from other environments were more sensitive to New Zealand phages. Lysogeny was more prevalent in Spanish S. aureus compared to New Zealand strains. A multiplex PCR reaction, which detected ΦH5 and ΦA72 sequences, indicated a high prevalence of these prophages in Spanish S. aureus strains, but were infrequently detected in New Zealand strains. Overall, the correlation between phage resistance and lysogeny in S. aureus strains was found to be weak. PMID:27111797

  18. Differential Analysis of the Nasal Microbiome of Pig Carriers or Non-Carriers of Staphylococcus aureus.

    Science.gov (United States)

    Espinosa-Gongora, Carmen; Larsen, Niels; Schønning, Kristian; Fredholm, Merete; Guardabassi, Luca

    2016-01-01

    Staphylococcus aureus is presently regarded as an emerging zoonotic agent due to the spread of specific methicillin-resistant S. aureus (MRSA) clones in pig farms. Studying the microbiota can be useful for the identification of bacteria that antagonize such opportunistic veterinary and zoonotic pathogen in animal carriers. The aim of this study was to determine whether the nasal microbiome of pig S. aureus carriers differs from that of non-carriers. The V3-V5 region of the 16S rRNA gene was sequenced from nasal swabs of 44 S. aureus carriers and 56 non-carriers using the 454 GS FLX titanium system. Carriers and non-carriers were selected on the basis of quantitative longitudinal data on S. aureus carriage in 600 pigs sampled at 20 Danish herds included in two previous studies in Denmark. Raw sequences were analysed with the BION meta package and the resulting abundance matrix was analysed using the DESeq2 package in R to identify operational taxonomic units (OTUs) with differential abundance between S. aureus carriers and non-carriers. Twenty OTUs were significantly associated to non-carriers, including species with known probiotic potential and antimicrobial effect such as lactic acid-producing isolates described among Leuconostoc spp. and some members of the Lachnospiraceae family, which is known for butyrate production. Further 5 OTUs were significantly associated to carriage, including known pathogenic bacteria such as Pasteurella multocida and Klebsiella spp. Our results show that the nasal microbiome of pigs that are not colonized with S. aureus harbours several species/taxa that are significantly less abundant in pig carriers, suggesting that the nasal microbiota may play a role in the individual predisposition to S. aureus nasal carriage in pigs. Further research is warranted to isolate these bacteria and assess their possible antagonistic effect on S. aureus for the pursuit of new strategies to control MRSA in pig farming. PMID:27509169

  19. Cost-effectiveness of preoperative screening and eradication of Staphylococcus aureus carriage.

    Directory of Open Access Journals (Sweden)

    Marjan W M Wassenberg

    Full Text Available BACKGROUND: Preoperative screening for nasal S. aureus carriage, followed by eradication treatment of identified carriers with nasal mupirocine ointment and chlorhexidine soap was highly effective in preventing deep-seated S. aureus infections. It is unknown how cost-effectiveness of this intervention is affected by suboptimal S. aureus screening. We determined cost-effectiveness of different preoperative S. aureus screening regimes. METHODS: We compared different screening scenarios (ranging from treating all patients without screening to treating only identified S. aureus carriers to the base case scenario without any screening and treatment. Screening and treatment costs as well as costs and mortality due to deep-seated S. aureus infection were derived from hospital databases and prospectively collected data, respectively. RESULTS: As compared to the base case scenario, all scenarios are associated with improved health care outcomes at reduced costs. Treating all patients without screening is most cost-beneficial, saving €7339 per life year gained, as compared to €3330 when only identified carriers are treated. In sensitivity analysis, outcomes are susceptible to the sensitivity of the screening test and the efficacy of treatment. Reductions in these parameters would reduce the cost-effectiveness of scenarios in which treatment is based on screening. When only identified S. aureus carriers are treated costs of screening should be less than €6.23 to become the dominant strategy. CONCLUSIONS: Preoperative screening and eradication of S. aureus carriage to prevent deep-seated S. aureus infections saves both life years and medical costs at the same time, although treating all patients without screening is the dominant strategy, resulting in most health gains and largest savings.

  20. Differential Analysis of the Nasal Microbiome of Pig Carriers or Non-Carriers of Staphylococcus aureus

    Science.gov (United States)

    Espinosa-Gongora, Carmen; Larsen, Niels; Schønning, Kristian; Fredholm, Merete; Guardabassi, Luca

    2016-01-01

    Staphylococcus aureus is presently regarded as an emerging zoonotic agent due to the spread of specific methicillin-resistant S. aureus (MRSA) clones in pig farms. Studying the microbiota can be useful for the identification of bacteria that antagonize such opportunistic veterinary and zoonotic pathogen in animal carriers. The aim of this study was to determine whether the nasal microbiome of pig S. aureus carriers differs from that of non-carriers. The V3-V5 region of the 16S rRNA gene was sequenced from nasal swabs of 44 S. aureus carriers and 56 non-carriers using the 454 GS FLX titanium system. Carriers and non-carriers were selected on the basis of quantitative longitudinal data on S. aureus carriage in 600 pigs sampled at 20 Danish herds included in two previous studies in Denmark. Raw sequences were analysed with the BION meta package and the resulting abundance matrix was analysed using the DESeq2 package in R to identify operational taxonomic units (OTUs) with differential abundance between S. aureus carriers and non-carriers. Twenty OTUs were significantly associated to non-carriers, including species with known probiotic potential and antimicrobial effect such as lactic acid-producing isolates described among Leuconostoc spp. and some members of the Lachnospiraceae family, which is known for butyrate production. Further 5 OTUs were significantly associated to carriage, including known pathogenic bacteria such as Pasteurella multocida and Klebsiella spp. Our results show that the nasal microbiome of pigs that are not colonized with S. aureus harbours several species/taxa that are significantly less abundant in pig carriers, suggesting that the nasal microbiota may play a role in the individual predisposition to S. aureus nasal carriage in pigs. Further research is warranted to isolate these bacteria and assess their possible antagonistic effect on S. aureus for the pursuit of new strategies to control MRSA in pig farming. PMID:27509169

  1. D-Test Method for Detection of Inducible Clindamycin Resistance in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Iraj Sedighi

    2009-09-01

    Full Text Available Objective:Methicillin resistant staphylococcus aureus (MRSA is a frequent cause of infections in children. The purpose of this study was to determine the frequency of nasal colonization of S. aureus in children and detection of inducible clindamycin resistance (ICR by disk approximation test (D-test.Methods:This was a cross-sectional study conducted in Hamedan from 2007 to 2008. 520 nasal swabs were obtained from children under 12 years of age at the time of admission and 287 swabs at the time of discharge. Antibiogram was performed by method of disk diffusion for oxacillin, erythromycin, clindamycin, cefazolin and vancomycin as well as D-test. Chi-square test was applied for statistical analysis.Findings:Out of 520 patients, 118 (22.3% were colonized with S. aureus as community-acquired (CA-S. aureus. Of 287 patients, 64 (22.3% were colonized with isolates of S. aureus at discharge time. Of these 64 patients, 32 cases were colonized with hospital acquired (HA-S. aureus isolates after admission. Only one CA-MRSA isolate was resistant to clindamycin, 5% of 118 CA-S. aureus isolates and 6.3% of HA-S. aureus isolates had inducible clindamycin resistance (D-test. Also 37.5% of CA-MRSA isolates at the time of admission and 22.2% of HA-MRSA isolates at discharge had positive D-test.Conclusion:We emphasize that D-test should be used routinely and clindamycin should not be used in patients with infections caused by inducible resistant S. aureus.

  2. Antimicrobial activity of some sulfonamide derivatives on clinical isolates of Staphylococus aureus

    Directory of Open Access Journals (Sweden)

    Bekdemir Yunus

    2008-08-01

    Full Text Available Abstract Background Staphylococcus aureus is a non-motile, gram positive, non-sporforming, facultative anaerobic microorganism. It is one of the important bacteria as a potential pathogen specifically for nosocomial infections. The sulfonamide derivative medicines are preferred to cure infection caused by S. aureus due to methicillin resistance. Methods Antimicrobial activity of four sulfonamide derivatives have been investigated against 50 clinical isolates of S. aureus and tested by using MIC and disc diffusion methods. 50 clinical isolate which collected from specimens of patients who are given medical treatment in Ondokuz Mayis University Medical School Hospital. A control strain of S. aureus ATCC 29213 was also tested. Results The strongest inhibition was observed in the cases of I [N-(2-hydroxy-4-nitro-phenyl-4-methyl-benzensulfonamid], and II [N-(2-hydroxy-5-nitro-phenyl-4-methyl-benzensulfonamid] against S. aureus. Compound I [N-(2-hydroxy-4-nitro-phenyl-4-methyl-benzensulfonamid] showed higher effect on 21 S. aureus MRSAisolates than oxacillin antibiotic. Introducing an electron withdrawing on the ring increased the antimicrobial activity remarkably. Conclusion This study may help to suggest an alternative possible leading compound for development of new antimicrobial agents against MRSA and MSSA resistant S. aureus. It was also shown here that that clinical isolates of 50 S. aureus have various resistance patterns against to four sulfonamide derivatives. It may also be emphasized here that in vitro antimicrobial susceptibility testing results for S. aureus need standardization with further studies and it should also have a correlation with in vivo therapeutic response experiments.

  3. Prevalence and Antimicrobial Susceptibility of Staphylococcus aureus Isolated from Nasal Carriers

    Directory of Open Access Journals (Sweden)

    Hedieh Moradi-Tabriz

    2015-10-01

    Full Text Available Background: Staphylococcus aureus (S. aureus is one of the major virulence factors of hospital and community acquired infections. Healthcare workers can be the host of S.aureus for many months. And it is very important due to the possibility of transmission to patients. Theaim of this study was to determine the prevalence of S.aureus nasal carriers, the antibiotic susceptibility pattern and its effective factors on Sina Hospital workers in Tehran, Iran.Methods: healthcare workers from different wards of Sina Hospital were studied in Tehran, Iran in 2010. Samples were taken from both nostrils of each individual. After 18-24hr incubation, the isolates were evaluated by gram stain, catalase, coagulase, DNase and manitol salt agar bywhich staphylococci were isolated. Disk diffusion antimicrobial susceptibility tests against oxacillin, cefoxitin and vancomycin was performed. Finally, by using PCR, the mecA gene was studied in methicillin-resistant strains (MRSA.Results: 34of the 166 workers, were nasal carriers of S. aureus and one of them was MRSA. The ratio of carriers in operating room workers was more than other wards, without significant relationship (p.value>0.05. S.aureus was found in 34.3% of operating room, 13.8% of nurses and 22.7% of licensed and other personnel. There was a significant relationship betweenoccupations and S.aureus carriage (p.value:0.03.Conclusion: According to the low prevalence of S. aureus and MRSA carriers in Sina hospital, it can be said that the role of the hospital staff as a source of infections caused by S. aureus especially is very low.

  4. Molecular characterization of methicillin-resistant Staphylococcus aureus recovered from outpatient clinics in Riyadh, Saudi Arabia

    International Nuclear Information System (INIS)

    To examine the recovered strains phenotypically, by conventional methods and genotypically by polymerase chain reaction (PCR), for direct detection of Staphylococcus aureus (S. aureus) 16S ribosomal Ribonucleic Acid (rRNA) gene (which serves as an internal control) and mecA gene. Secondly, introduce multiplex PCR targeting at the same time S. aureus 16S rRNA, Panton-Valentine Leucocidin (PVL), and staphylococcal cassette chromosome mec (SCCmec) type 4. Thirty-seven strains of S. aureus collected in 2007 from outpatient clinics in King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia, were tested in the College of Pharmacy phenotypically by conventional methods and genotypically by PCR for direct detection of S. aureus 16S rRNA and mecA genes. All the 37 strains, were tested also by multiplex PCR targeting at the same time S. aureus 16S rRNA, PVL, and (SCCmec) type 4. Polymerase chain reaction detected all the 37 bacteriologically positive S. aureus (100%) and the mecA gene in all strains phenotypically resistant to methicillin (100%), at the same time it detected the mecA gene in 2 strains phenotypically sensitive to methicillin. Only 3 strains (8.1%) recovered from skin and soft tissue infections were positive for PVL and SCCmec type 4. The PCR assay can be used for rapid detection of S. aureus and mecA gene. At the same time the multiplex PCR assay explained in this study is a rapid, sensitive, and reliable test for direct detection of community-acquired methicillin-resistant S. aureus. (author)

  5. Effects of nisin on Staphylococcus aureus count and physicochemical properties of Minas Frescal cheese.

    Science.gov (United States)

    Felicio, Bruna A; Pinto, Maximiliano S; Oliveira, Francielly S; Lempk, Marcus W; Pires, Ana Clarissa S; Lelis, Carini A

    2015-07-01

    The aim of this work was to evaluate the effects of nisin on in vitro and in situ Staphylococcus aureus counts. For in vitro experiment, milk was inoculated with 5.0 log cfu·mL(-1) of S. aureus and nisin was added at concentrations of 0, 100, 200, 400, and 500 IU mL(-1). The main effect of the bacteriocin was lag phase extension from 0h, for 0 and 100 IU·mL(-1) to 8h, when 200, 400, and 500 IU·mL(-1) of nisin were used; however, log phase was not affected. Microbial growth rate was found to be exponential and around 0.11 log cfu·mL(-1)·h(-1) for all treatments. For in situ experiments, 0, 400, and 500 IU·mL(-1) of nisin were directly added to pasteurized milk previously inoculated with 5.0 log cfu·g(-1) of S. aureus. Milk, curd, and whey were analyzed to S. aureus counts. Nisin at concentration of 500 IU·mL(-1) was able to reduce S. aureus count in curd and whey, demonstrating nisin partition between both phases. Throughout storage at 4°C, S. aureus count increased for all treatments, but the bacterial grew slower when nisin was added in both concentrations, maintaining S. aureus count about 1.5 log cycles lower than the control, despite abusive initial S. aureus count. Therefore, nisin seems to play an important role in reducing S. aureus initial count in cheese made with highly contaminated milk. Nisin showed potential to be used as an additional, important hurdle to improve Minas Frescal cheese safety, without replacing good manufacturing practices. PMID:25981063

  6. Immunological role of nasal staphylococcus aureus carriage in patients with persistent allergic rhinitis

    Directory of Open Access Journals (Sweden)

    Mohamed Yousif Atia

    2008-10-01

    Full Text Available Nasal carriage of staphylococcus aureus (S.aureus exerts immunomodulatory effect in patients with atopic dermatitis and it may contribute to airway inflammation and allergic response in patients with allergic rhinitis. We Aim to investigate the frequency of nasal S.aureus carriage in patients with persistent allergic rhinitis and its possible influence on their symptoms and immune markers. We chosed 20 non smoker patients with house dust mite (HDM allergy causing allergic rhinitis and 20 non smoker healthy subjects matched for age and sex. For all subjects rhinoscopy was done, skin prick test, nasal culture for S.aureus, nasal interleukin 4,nasal total IgE, serum total IgE and serum specific IgE(SSIgE for HDM. Nasal S.aureus was detected in 16/20 patients (80% and 5/20 (25% in healthy subjects with highly significant statistical difference plt0.01. Correlation of nasal staph.aureus count and different systemic and local immune markers revealed highly significant positive correlation between nasal S.aureus count and serum total IgE (r = 0.78, plt0.01 and significant positive correlation with SSIgE (HDM (r = 0.53, plt0.05, nasal total IgE (r = 0.39, plt0.05 and nasal IL-4 (r = 0.55, plt0.05. Nasal staph.aureus actively modulated the immune reaction in persistent allergic rhinitis patients by promoting local IgE production, so we recommend early detection and treatment of S.aureus carriage in patients

  7. Tracing and inhibiting growth of Staphylococcus aureus in barbecue cheese production after product recall.

    Science.gov (United States)

    Johler, S; Zurfluh, K; Stephan, R

    2016-05-01

    Staphylococcal food poisoning is one of the most prevalent causes of foodborne intoxication worldwide. It is caused by ingestion of enterotoxins formed by Staphylococcus aureus during growth in the food matrix. Following a recall of barbecue cheese due to the detection of staphylococcal enterotoxins in Switzerland in July 2015, we analyzed the production process of the respective dairy. Although most cheese-making processes involve acidification to inhibit the growth of pathogenic bacteria, barbecue cheese has to maintain a pH >6.0 to prevent undesired melting of the cheese. In addition, the dairy decided to retain the traditional manual production process of the barbecue cheese. In this study, therefore, we aimed to (1) trace Staph. aureus along the barbecue cheese production process, and (2) develop a sustainable strategy to inhibit growth of Staph. aureus and decrease the risk of staphylococcal food poisoning without changing the traditional production process. To this end, we traced Staph. aureus in a step-wise blinded process analysis on 4 different production days using spa (Staphylococcus protein A gene) typing, DNA microarray profiling, and pulsed-field gel electrophoresis analysis. We subsequently selected a new starter culture and used a model cheese production including a challenge test assay to assess its antagonistic effect on Staph. aureus growth, as well as its sensory and technological implications. We detected Staph. aureus in 30% (37/124) of the collected samples taken from the barbecue cheese production at the dairy. This included detection of Staph. aureus in the final product on all 4 production days, either after enrichment or using quantitative detection. We traced 2 enterotoxigenic Staph. aureus strains (t073/CC45 and t282/CC45) colonizing the nasal cavity and the forearms of the cheesemakers to the final product. In the challenge test assay, we were able to show that the new starter culture inhibited growth of Staph. aureus while meeting

  8. [Clonal eosinophilia revealed by recurrent Staphylococcus aureus infection].

    Science.gov (United States)

    Vandenbos, F; Figueredo, M; Dumon-Gubeno, M-C; Nicolle, I; Tarhini, A; Medioni, L-D; Naman, H; Mouroux, J

    2011-06-01

    Acquired eosinophilia is currently classified into secondary (reactional to underlying diseases), clonal (presence of a bone marrow histological, cytogenetic or molecular marker of a myeloid malignancy) and idiopathic (neither secondary nor clonal) categories. We report the case of a 47-year-old male who was admitted to the hospital for Staphylococcus aureus recurring infections. An hypereosinophilia was discovered and led to molecular analysis. The identification of FIP1L1-PDGFRA fusion gene permitted the diagnostic of clonal eosinophilia. Treatment by imatinib mesylate induced an haematological remission, the control of the infection and thoracotomy cicatrization. This case is original because of its infectious presentation and the efficacy of imatinib mesylate to control the infectious process. PMID:21665081

  9. Nanoadhesion of Staphylococcus aureus onto Titanium Implant Surfaces.

    Science.gov (United States)

    Aguayo, S; Donos, N; Spratt, D; Bozec, L

    2015-08-01

    Adhesion of bacteria to dental implant surfaces is the critical initial step in the process of biofilm colonization; however, the specific nanoadhesive interactions occurring during the first contact between bacterial cells and biomaterial substrates remain poorly understood. In this report, we utilize single-cell force spectroscopy to characterize the dynamics of the initial interaction between living Staphylococcus aureus cells and machined titanium surfaces at the nanoscale. Values for maximum adhesion force were found to increase from 0-s (-0.27 ± 0.30 nN) to 60-s (-9.15 ± 0.78 nN) surface delays, with similar results observed for total adhesion work (7.39 ± 2.38 and 988.06 ± 117.08 aJ, respectively). Single unbinding events observed at higher surface delays were modeled according to the wormlike chain model, obtaining molecular contour-length predictions of 314.06 ± 9.27 nm. Average single-bond rupture forces of -0.95 ± 0.04 nN were observed at increased contact times. Short- and long-range force components of bacterial adhesion were obtained by Poisson analysis of single unbinding event peaks, yielding values of -0.75 ± 0.04 and -0.58 ± 0.15 nN, respectively. Addition of 2-mg/mL chlorhexidine to the buffer solution resulted in the inhibition of specific adhesive events but an increased overall adhesion force and work. These results suggest that initial attachment of S. aureus to smooth titanium is mostly mediated by short-range attractive forces observed at higher surface delays. PMID:26130256

  10. Complete Reconstitution of the Vancomycin-Intermediate Staphylococcus aureus Phenotype of Strain Mu50 in Vancomycin-Susceptible S. aureus.

    Science.gov (United States)

    Katayama, Yuki; Sekine, Miwa; Hishinuma, Tomomi; Aiba, Yoshifumi; Hiramatsu, Keiichi

    2016-06-01

    Complete reconstitution of the vancomycin-intermediate Staphylococcus aureus (VISA) phenotype of strain Mu50 was achieved by sequentially introducing mutations into six genes of vancomycin-susceptible S. aureus (VSSA) strain N315ΔIP. The six mutated genes were detected in VISA strain Mu50 but not in N315ΔIP. Introduction of the mutation Ser329Leu into vraS, encoding the sensor histidine kinase of the vraSR two-component regulatory (TCR) system, and another mutation, Glu146Lys, into msrR, belonging to the LytR-CpsA-Psr (LCP) family, increased the level of vancomycin resistance to that detected in heterogeneous vancomycin-intermediate S. aureus (hVISA) strain Mu3. Introduction of two more mutations, Asn197Ser into graR of the graSR TCR system and His481Tyr into rpoB, encoding the β subunit of RNA polymerase, converted the hVISA strain into a VISA strain with the same level of vancomycin resistance as Mu50. Surprisingly, however, the constructed quadruple mutant strain ΔIP4 did not have a thickened cell wall, a cardinal feature of the VISA phenotype. Subsequent study showed that cell wall thickening was an inducible phenotype in the mutant strain, whereas it was a constitutive one in Mu50. Finally, introduction of the Ala297Val mutation into fdh2, which encodes a putative formate dehydrogenase, or a 67-amino-acid sequence deletion into sle1 [sle1(Δ67aa)], encoding the hydrolase of N-acetylmuramyl-l-alanine amidase in the peptidoglycan, converted inducible cell wall thickening into constitutive cell wall thickening. sle1(Δ67aa) was found to cause a drastic decrease in autolysis activity. Thus, all six mutated genes required for acquisition of the VISA phenotype were directly or indirectly involved in the regulation of cell physiology. The VISA phenotype seemed to be achieved through multiple genetic events accompanying drastic changes in cell physiology. PMID:27067329

  11. Isolation of Staphylococcus aureus L forms from experimentally induced bovine mastitis.

    OpenAIRE

    Owens, W E

    1987-01-01

    Bacterial L forms were isolated from milk samples of dairy cattle infected experimentally with Staphylococcus aureus. Initially, bacterial L forms were induced in vitro from 12 of 44 S. aureus strains isolated from bovine mastitis. Cows were experimentally infected in two experiments with strains shown in vitro to be easily inducible to L form and with S. aureus Newbould 305. Each quarter of the mammary gland was infected with either 10(3) or 10(6) CFU of the test strains. Treatment was initi...

  12. Virulence Factors of Staphylococcus aureus Isolated from Korean Pork bulgogi: Enterotoxin Production and Antimicrobial Resistance

    OpenAIRE

    Jung, Byeong Su; Lee, Yong Ju; Lee, Na-Kyoung; Kim, Hyoun Wook; Oh, Mi-Hwa; Paik, Hyun-Dong

    2015-01-01

    The aim of this study was to investigate the antimicrobial resistance profiles of and the enterotoxin gene distribution in 4 strains of Staphylococcus aureus (S10-2, S10-3, S12-2, and S13-2) isolated from 90 bulgogi samples. The S. aureus enterotoxin H gene (seh) was found in all the strains, while the S. aureus enterotoxin A gene (sea) was found only in 3 of the 4 strains. The S10-2 strain expressed a combination of enterotoxin genes - seg, seh, sei, sej, selm, and seln. The strains S10-2 an...

  13. Genomic characterization of ribitol teichoic acid synthesis in Staphylococcus aureus: genes, genomic organization and gene duplication

    Directory of Open Access Journals (Sweden)

    Lu Lingyi

    2006-04-01

    Full Text Available Abstract Background Staphylococcus aureus or MRSA (Methicillin Resistant S. aureus, is an acquired pathogen and the primary cause of nosocomial infections worldwide. In S. aureus, teichoic acid is an essential component of the cell wall, and its biosynthesis is not yet well characterized. Studies in Bacillus subtilis have discovered two different pathways of teichoic acid biosynthesis, in two strains W23 and 168 respectively, namely teichoic acid ribitol (tar and teichoic acid glycerol (tag. The genes involved in these two pathways are also characterized, tarA, tarB, tarD, tarI, tarJ, tarK, tarL for the tar pathway, and tagA, tagB, tagD, tagE, tagF for the tag pathway. With the genome sequences of several MRSA strains: Mu50, MW2, N315, MRSA252, COL as well as methicillin susceptible strain MSSA476 available, a comparative genomic analysis was performed to characterize teichoic acid biosynthesis in these S. aureus strains. Results We identified all S. aureus tar and tag gene orthologs in the selected S. aureus strains which would contribute to teichoic acids sythesis.Based on our identification of genes orthologous to tarI, tarJ, tarL, which are specific to tar pathway in B. subtilis W23, we also concluded that tar is the major teichoic acid biogenesis pathway in S. aureus. Further analyses indicated that the S. aureus tar genes, different from the divergon organization in B. subtilis, are organized into several clusters in cis. Most interesting, compared with genes in B. subtilis tar pathway, the S. aureus tar specific genes (tarI,J,L are duplicated in all six S. aureus genomes. Conclusion In the S. aureus strains we analyzed, tar (teichoic acid ribitol is the main teichoic acid biogenesis pathway. The tar genes are organized into several genomic groups in cis and the genes specific to tar (relative to tag: tarI, tarJ, tarL are duplicated. The genomic organization of the S. aureus tar pathway suggests their regulations are different when

  14. Ability of Staphylococcus aureus coagulase genotypes to resist neutrophil bactericidal activity and phagocytosis

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Scott, N. L.; Sordillo, L. M.

    1994-01-01

    This study investigated the functional capabilities of neutrophils against different Staphylococcus aureus genotypes isolated from cows with mastitis. Six strains of S. aureus were chosen for use in the study, two with a common genotype, two with an intermediate genotype, and two with a rare.......26/cell; rare type, 10.5/cell). These findings suggest that one of the reasons for the variation in prevalence of different genotypes of S. aureus in the mammary gland is due to the superior ability of some types to resist phagocytosis and/or killing by bovine neutrophils...

  15. Efficacy of dicloxacillin-coated polyurethane catheters in preventing subcutaneous Staphylococcus aureus infection in mice.

    OpenAIRE

    Sherertz, R J; Forman, D M; Solomon, D D

    1989-01-01

    In a mouse model, dicloxacillin-coated polyurethane catheters or control (uncoated) catheters were placed subcutaneously and then Staphylococcus aureus was inoculated at the time of insertion, 24 or 48 h later. The in vivo half-life of the antibiotic was 11 to 16 h. When 10(5) CFU of S. aureus were inoculated at the time of catheter insertion, dicloxacillin-coated catheters kept the number of S. aureus removed from catheters by sonication below 10(2) CFU at 12, 24, 48, and 96 h after inoculat...

  16. Antibiotic Resistance in Staphylococcus aureus and Coagulase Negative Staphylococci Isolated from Goats with Subclinical Mastitis

    OpenAIRE

    Salvatore Virdis; Christian Scarano; Francesca Cossu; Vincenzo Spanu; Carlo Spanu; Enrico Pietro Luigi De Santis

    2010-01-01

    Antimicrobial resistance patterns and gene coding for methicillin resistance (mecA) were determined in 25 S. aureus and 75 Coagulase Negative Staphylococci (CNS) strains isolates from half-udder milk samples collected from goats with subclinical mastitis. Fourteen (56.0%) S. aureus and thirty-one (41.3%) CNS isolates were resistant to one or more antimicrobial agents. S. aureus showed the highest resistance rate against kanamycin (28.0%), oxytetracycline (16.0%), and ampicillin (12.0%). The C...

  17. Staphylococcus aureus Strains That Express Serotype 5 or Serotype 8 Capsular Polysaccharides Differ in Virulence

    OpenAIRE

    Watts, Andrew; Ke, Danbing; Wang, Qun; Pillay, Anil; Nicholson-Weller, Anne; Lee, Jean C.

    2005-01-01

    Most isolates of Staphylococcus aureus produce a serotype 5 (CP5) or 8 (CP8) capsular polysaccharide. To investigate whether CP5 and CP8 differ in their biological properties, we created isogenic mutants of S. aureus Reynolds that expressed CP5, CP8, or no capsule. Biochemical analyses of CP5 and CP8 purified from the isogenic S. aureus strains were consistent with published structures. The degree of O acetylation of each polysaccharide was similar, but CP5 showed a greater degree of N acetyl...

  18. Detection of methicillin resistance and slime factor production of Staphylococcus aureus in bovine mastitis

    OpenAIRE

    Alper Ciftci; Arzu Findik; Ertan Emek Onuk; Serap Savasan

    2009-01-01

    This study aimed to detect methicillin resistant and slime producing Staphylococcus aureus in cases of bovine mastitis. A triplex PCR was optimized targetting 16S rRNA, nuc and mecA genes for detection of Staphylococcus species, S. aureus and methicillin resistance, respectively. Furthermore, for detection of slime producing strains, a PCR assay targetting icaA and icaD genes was performed. In this study, 59 strains were detected as S. aureus by both conventional tests and PCR, and 13 of them...

  19. Staphylococcus aureus and the ecology of the nasal microbiome

    DEFF Research Database (Denmark)

    Liu, Cindy M; Price, Lance B; Hungate, Bruce A;

    2015-01-01

    The human microbiome can play a key role in host susceptibility to pathogens, including in the nasal cavity, a site favored by Staphylococcus aureus. However, what determines our resident nasal microbiota-the host or the environment-and can interactions among nasal bacteria determine S. aureus......, their negative interactions depend on thresholds of absolute abundance. These findings demonstrate that nasal microbiota is not fixed by host genetics and opens the possibility that nasal microbiota may be manipulated to prevent or eliminate S. aureus colonization....

  20. Solonamide B Inhibits Quorum Sensing and Reduces Staphylococcus aureus Mediated Killing of Human Neutrophils

    DEFF Research Database (Denmark)

    Nielsen, Anita; Månsson, Maria; Bojer, Martin S.;

    2014-01-01

    that a cyclodepsipeptide termed Solonamide B isolated from the marine bacterium, Photobacterium halotolerans strongly reduces expression of RNAIII, the effector molecule of the agr quorum sensing system. Here we show that Solonamide B interferes with the binding of S. aureus autoinducing peptides (AIPs) to sensor......A controlled virulence gene expression in S. aureus.......Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a serious human pathogen, and particularly the spread of community associated (CA)-MRSA strains such as USA300 is a concern, as these strains can cause severe infections in otherwise healthy adults. Recently, we reported...

  1. Effectiveness of penicillin, dicloxacillin and cefuroxime for penicillin-susceptible Staphylococcus aureus bacteraemia

    DEFF Research Database (Denmark)

    Nissen, Jette Lindbjerg; Skov, Robert; Knudsen, Jenny Dahl;

    2013-01-01

    OBJECTIVES: Penicillin-susceptible Staphylococcus aureus isolates account for a fifth of cases of S. aureus bacteraemia (SAB) in Denmark, but little is known about treatment outcomes with penicillins or other antimicrobials. Here we compare penicillin, dicloxacillin and cefuroxime as definitive...... treatments in relation to 30 day mortality. METHODS: A retrospective chart review of 588 penicillin-susceptible S. aureus cases at five centres from January 1995 to December 2010. Data on demographics, antimicrobial treatment, clinical signs and symptoms, and mortality at day 30 were collected. Hazard ratios...

  2. Three cases of severely disseminated Staphylococcus aureus infection in patients treated with tocilizumab

    DEFF Research Database (Denmark)

    Nguyen, Mai; Pødenphant, Jan; Ravn, Pernille

    2013-01-01

    -intensive diagnostic work-up and early treatment should be performed. Systematic postmarketing studies are needed to clarify if there is a true increased risk of disseminated S aureus infections. We suggest caution when prescribing tocilizumab to patients with prosthetic joints and/or prior invasive S aureus......We report three cases of severe disseminated Staphylococcus aureus infection in patients with rheumatoid arthritis (RA) treated with tocilizumab. Tocilizumab is a new drug, unknown to most internists, and injections given weeks before admission may not be considered by the patient as part...

  3. Ability of Staphylococcus aureus coagulase genotypes to resist neutrophil bactericidal activity and phagocytosis

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Scott, N. L.; Sordillo, L. M.

    1994-01-01

    This study investigated the functional capabilities of neutrophils against different Staphylococcus aureus genotypes isolated from cows with mastitis. Six strains of S. aureus were chosen for use in the study, two with a common genotype, two with an intermediate genotype, and two with a rare......; rare type, 10.5/cell). These findings suggest that one of the reasons for the variation in prevalence of different genotypes of S. aureus in the mammary gland is due to the superior ability of some types to resist phagocytosis and/or killing by bovine neutrophils...

  4. Future challenges and treatment of Staphylococcus aureus bacteremia with emphasis on MRSA

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Fowler, Vance G; Skov, Robert;

    2011-01-01

    . Compounding this problem is the growing prevalence of methicillin-resistant S. aureus (MRSA) and the dwindling efficacy of vancomycin, long the treatment of choice for this pathogen. Despite the recent availability of several new antibiotics for S. aureus, new strategies for treatment and prevention......Staphylococcus aureus bacteremia (SAB) is an urgent medical problem due to its growing frequency and its poor associated outcome. As healthcare delivery increasingly involves invasive procedures and implantable devices, the number of patients at risk for SAB and its complications is likely to grow...

  5. Phage types and antimicrobial resistance among Danish bovine Staphylococcus aureus isolates since the 1950s

    DEFF Research Database (Denmark)

    Vintov, Jan; Aarestrup, Frank Møller; Zinn, C. E.;

    2003-01-01

    A total of 292 bovine Staphylococcus aureus isolates obtained from the 1950s (86 isolates), 1992 (107 isolates), and 2000 (99 isolates) were examined for antimicrobial susceptibility and phage typing. The same types of S. aureus (80, 52, 3A, 3A/3C, 42E, 77) were found among the isolates from all...... three time periods, representing 43.3% of the typeable isolates. This indicates that the Danish S. aureus population related to bovine mastitis has remained relatively unchanged over the last 50 years. The occurrence of antimicrobial resistance has remained low in Denmark in comparison to other...

  6. Major cerebral events in Staphylococcus aureus infective endocarditis: is anticoagulant therapy safe?

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Snygg-Martin, Ulrika; Olaison, Lars;

    2009-01-01

    -hospital mortality was 23% (95% CI: 17-29%), and there was no significant difference between those with or without anticoagulation. CONCLUSIONS: We found no increased risk of cerebral haemorrhage in S. aureus IE patients receiving anticoagulation. Anticoagulation was associated with a reduced risk of cerebral events...... before initiation of antibiotics. Data support the continuance of anticoagulation in S. aureus IE patients when indicated.......OBJECTIVES: To study the impact of anticoagulation on major cerebral events in patients with left-sided Staphylococcus aureus infective endocarditis (IE). METHODS: A prospective cohort study; the use of anticoagulation and the relation to major cerebral events was evaluated separately at onset...

  7. Determination of phagocytosis of 32P-labeled Staphylococcus aureus by bovine polymorphonuclear leukocytes

    International Nuclear Information System (INIS)

    A procedure for the measurement of phagocytosis by bovine polymorphonuclear leukocytes (PMN) of 32P-labeled Staphylococcus aureus was modified so that a larger number of samples could be compared in a single run, and smaller volumes of sample, PMN, and 32P-labeled S aureus could be used. Results were highly reproducible, with a coefficient of variation between duplicate determinations of less than or equal to 2%. Lysostaphin was prepared from the supernatant of S staphylolyticus and was compared with a commercially available preparation. Effects of lysostaphin on PMN and influence of incubation media on release of 32P from 32P-labeled S aureus by lysostaphin were examined

  8. Eficacia de la infiltración de ozono paravertebral lumbar y en puntos gatillos como coadyuvante del tratamiento en pacientes con dolor lumbar crónico y lumbociatalgia crónica en el síndrome doloroso miofascial aislado o acompañado de otras patologías

    Directory of Open Access Journals (Sweden)

    E. Silva Jiménez

    2014-02-01

    Full Text Available Introducción: Posterior al primer episodio de dolor lumbar, la recurrencia persiste durante un año o más en el 25 al 60 %, afectando a población económicamente activa, causando discapacidad y en 80 % ausentismo laboral. Objetivo: Evaluar el grado de eficacia del uso de la técnica de infiltración con ozono paravertebral lumbar y en puntos gatillos junto al tratamiento farmacológico y rehabilitador, en pacientes con dolor lumbar crónico y lumbociatalgia crónica debido al síndrome doloroso miofascial (SDM aislado o acompañado de otras patologías. Métodos: Estudio no probabilístico, de tipo experimental controlado, doble ciego. Se estudiaron 43 pacientes (22 experimental y 21 control. El grupo experimental recibió ozono paravertebral lumbar y en puntos gatillos más tratamiento farmacológico y rehabilitador. El grupo control recibió tratamiento farmacológico y rehabilitador. Se aplicó en ambos grupos la escala de EVA, Oswestry y la medición de los grados de flexión del tronco al inicio, dos y cuatro semanas posterior al comienzo del tratamiento. Resultados: La aplicación de ozono paravertebral lumbar y en puntos gatillos, junto al tratamiento farmacológico y rehabilitador, en el manejo de pacientes con dolor lumbar y lumbociatalgia crónica, comparado con solo tratamiento farmacológico y rehabilitador, resultó ser más eficaz, con significancia estadística (p < 0,05 para disminuir la intensidad del dolor (90,5 %, la incapacidad funcional (90,5 %, y aumentó los grados de flexión del tronco (85,7 % versus 40,0, 70 y 75 % respectivamente, a las cuatro semanas posteriores al inicio del tratamiento. Se evidencia mejoría en pacientes con SDM aislado o acompañado de síndrome de receso lateral, síndrome facetario, grados variables de hernia discal excepto la extrusión central. Conclusiones: La infiltración de ozono paravertebral lumbar y en puntos gatillos junto al tratamiento farmacológico y rehabilitador resultó ser m

  9. Virulence Factors and Antibiotic Susceptibility of Staphylococcus aureus Isolates in Ready-to-Eat Foods: Detection of S. aureus Contamination and a High Prevalence of Virulence Genes.

    Science.gov (United States)

    Puah, Suat Moi; Chua, Kek Heng; Tan, Jin Ai Mary Anne

    2016-02-01

    Staphylococcus aureus is one of the leading causes of food poisoning. Its pathogenicity results from the possession of virulence genes that produce different toxins which result in self-limiting to severe illness often requiring hospitalization. In this study of 200 sushi and sashimi samples, S. aureus contamination was confirmed in 26% of the food samples. The S. aureus isolates were further characterized for virulence genes and antibiotic susceptibility. A high incidence of virulence genes was identified in 96.2% of the isolates and 20 different virulence gene profiles were confirmed. DNA amplification showed that 30.8% (16/52) of the S. aureus carried at least one SE gene which causes staphylococcal food poisoning. The most common enterotoxin gene was seg (11.5%) and the egc cluster was detected in 5.8% of the isolates. A combination of hla and hld was the most prevalent coexistence virulence genes and accounted for 59.6% of all isolates. Antibiotic resistance studies showed tetracycline resistance to be the most common at 28.8% while multi-drug resistance was found to be low at 3.8%. In conclusion, the high rate of S. aureus in the sampled sushi and sashimi indicates the need for food safety guidelines. PMID:26861367

  10. Virulence Factors and Antibiotic Susceptibility of Staphylococcus aureus Isolates in Ready-to-Eat Foods: Detection of S. aureus Contamination and a High Prevalence of Virulence Genes

    Directory of Open Access Journals (Sweden)

    Suat Moi Puah

    2016-02-01

    Full Text Available Staphylococcus aureus is one of the leading causes of food poisoning. Its pathogenicity results from the possession of virulence genes that produce different toxins which result in self-limiting to severe illness often requiring hospitalization. In this study of 200 sushi and sashimi samples, S. aureus contamination was confirmed in 26% of the food samples. The S. aureus isolates were further characterized for virulence genes and antibiotic susceptibility. A high incidence of virulence genes was identified in 96.2% of the isolates and 20 different virulence gene profiles were confirmed. DNA amplification showed that 30.8% (16/52 of the S. aureus carried at least one SE gene which causes staphylococcal food poisoning. The most common enterotoxin gene was seg (11.5% and the egc cluster was detected in 5.8% of the isolates. A combination of hla and hld was the most prevalent coexistence virulence genes and accounted for 59.6% of all isolates. Antibiotic resistance studies showed tetracycline resistance to be the most common at 28.8% while multi-drug resistance was found to be low at 3.8%. In conclusion, the high rate of S. aureus in the sampled sushi and sashimi indicates the need for food safety guidelines.

  11. Risk factors assessment for nasal colonization of Staphylococcus aureus and its methicillin resistant strains among pre-clinical medical students of Nepal

    OpenAIRE

    Ansari, Shamshul; Gautam, Rajendra; Shrestha, Sony; Ansari, Safiur Rahman; Subedi, Shankar Nanda; Chhetri, Muni Raj

    2016-01-01

    Background Staphylococcus aureus (S. aureus), a normal flora of nasal cavity, can cause minor to life threatening invasive diseases and nosocomial infections. Methicillin resistant strains of S. aureus are causing a great challenge for treatment options. Therefore, the purpose of this study was to assess the nasal carriage rate of S. aureus, its methicillin resistant strains and risk factors in medical students prior to clinical exposure. Methods The bacterial growth of S. aureus from nasal s...

  12. The Prevalence of Nasal Carriage of Staphylococcus Aureus Among Healthcare Workers at a Tertiary Care Hospital in Assam with Special Reference to MRSA

    OpenAIRE

    Rongpharpi, Sharon Rainy; Hazarika, Naba Kumar; Kalita, Hitesh

    2013-01-01

    Background: The recent years have witnessed the increasing resistance of Staphylococcus aureus to many antimicrobial agents. The most notable example is the emergence of Methicillin-resistant Staphylococcus aureus (MRSA), which was reported just one year after the launch of methicillin. The ecological niches of the S. aureus strains are the anterior nares. The identification of Staphylococcus aureus by using a proper antibiogram and the detection of methicillin resistant Staphylococcus aureus...

  13. The Lytic SA Phage Demonstrate Bactericidal Activity against Mastitis Causing Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Hamza Ameer

    2016-04-01

    Full Text Available Staphylococcus aureus is the major causative agent of mastitis among dairy animals as it causes intramammary gland infection. Due to antibiotic resistance and contamination of antibiotics in the milk of diseased animals; alternative therapeutic agents are required to cure mastitis. Lytic bacteriophages and their gene products can be potential therapeutic agents against bacteria as they are host specific and less harmful than antibiotics. In this study, Staphylococcus aureus were isolated from milk samples of the infected animals and identified biochemically. SA phage was isolated from sewage water showing lytic activity against Staphylococcus aureus isolates. The highest lytic activity of bacteriophages was observed at 37°C and pH 7, and the most suitable storage condition was at 4°C. SA phage efficiently reduced bacterial growth in the bacterial reduction assay. The characterization and bacterial growth reduction activity of the bacteriophages against Staphylococcus aureus signifies their underlying potential of phage therapy against mastitis.

  14. Tolerance of Salmonella Enteritidis and Staphylococcus aureus to surface cleaning and household bleach

    NARCIS (Netherlands)

    Kusumaningrum, H.D.; Paltinaite, R.; Koomen, A.J.; Hazeleger, W.C.; Rombouts, F.M.; Beumer, R.R.

    2003-01-01

    Effective cleaning and sanitizing of food preparation sites is important because pathogens are readily spread to food contact surfaces after preparation of contaminated raw products. Tolerance of Salmonella Enteritidis and Staphylococcus aureus to surface cleaning by wiping with regular, microfiber,

  15. A 220-kilodalton glycoprotein in yeast extract inhibits Staphylococcus aureus adherence to human endothelial cells.

    OpenAIRE

    Elliott, D.A.; Hatcher, V B; Lowy, F D

    1991-01-01

    A 220-kDa glycoprotein from yeast extract causes a twofold decrease in S. aureus adherence to human endothelial cells in vitro. Medium constituents can have a significant effect on bacterial adherence interactions.

  16. Treatment of Staphylococcus aureus keratitis with 0.2% topical linezolid

    Directory of Open Access Journals (Sweden)

    Lincoln Lavado Landeo

    2015-09-01

    Full Text Available Objective: To report the use of 0.2% topical linezolid in the treatment of Staphylococcus aureus keratitis with successful results. Material and methods: All cases were viewed in Centro Vision, here they underwent a complete ophthalmic examination and were diagnosed with Staphylococcus aureus keratitis based on a microbiological study. In both cases we began with the gold standard therapy based on fortified topical drops of vancomycin and an aminoglycoside. Due to ineffective action and/or poor tolerance of vancomycin, we decided to use topical linezolid. Results: Two female patients with Staphylococcus aureus keratitis received ocular 0.2% topical linezolid every hour. In both cases we saw a marked clinical improvement and a good tolerance to this antibiotic. Conclusions: 0.2% Topical linezolid is an effective and well tolerated antibiotic when used in the treatment of Staphylococcus aureus keratitis. It is more comfortable and less toxic than topical vancomycin.

  17. Non-spa-typeable clinical Staphylococcus aureus strains are naturally occurring protein A mutants

    DEFF Research Database (Denmark)

    Baum, Cathrin; Haslinger-Löffler, Bettina; Westh, Henrik;

    2009-01-01

    Staphylococcus aureus is a major human pathogen responsible for increasing the prevalence of community- and hospital-acquired infections. Protein A (SpA) is a key virulence factor of S. aureus and is highly conserved. Sequencing of the variable-number tandem-repeat region of SpA (spa typing......) provides a rapid and reliable method for epidemiological studies. Rarely, non-spa-typeable S. aureus strains are encountered. The reason for this is not known. In this study, we characterized eight non-spa-typeable bacteremia isolates. Sequencing of the entire spa locus was successful for five strains...... and revealed various mutations of spa, all of which included a deletion of immunoglobulin G binding domain C, in which the upper primer for spa typing is located, while two strains were truly spa negative. This is the first report demonstrating that nontypeability of S. aureus by spa sequencing is due either...

  18. Microcalorimetric Study of the Action of Yb3+ ion on the Growth of Staphylococcus aureus

    Institute of Scientific and Technical Information of China (English)

    侯安新; 薛智; 刘义; 屈松生

    2003-01-01

    A microcalorimetric method was used to evaluate the action of Yb3+ ions onthe growth metabolism of Staphylococcus aureus.The power-time curves of the growth metabolism of Staphylo.coccus aureus and the action of Yb3+ ions were obtained by us-ing stopped-flow method at 37 ℃. For evaluation of the action,the growth rate constants ( k1 and k2) for the log phase 1, log phase 2, and the total heat effect (Qtotal) for Staphylococcus aureus were determined. The results show that Yb3+ ions at low concentrations have the stimnlatory effect on Staphylococcus au-reus and that Yb3+ions at higher concentration could inhibit its growth.

  19. The incidence and risk factors for heterogeneous vancomycin intermediate Staphylococcus aureus

    Institute of Scientific and Technical Information of China (English)

    冯娜娜

    2013-01-01

    Objective To investigate the prevalence of heterogeneous vancomycin intermediate Staphylococcus aureus(hVISA) and the sensitivity of hVISA to novel antibiotics,and to explore the risk factors and infection attributable

  20. Staphylococcus aureus and influenza A virus stimulate human bronchoalveolar cells to release histamine and leukotrienes

    DEFF Research Database (Denmark)

    Clementsen, P; Bisgaard, H; Pedersen, M;

    1989-01-01

    Mediator release was examined from superficially lying cells in the airway epithelium obtained by bronchoalveolar lavage (BAL) in 13 non-atopic individuals. The BAL-cells were incubated (20 min, 37 degrees C) with Staphylococcus (Staph.) aureus or with human influenza A virus Staph. aureus...... was found to release histamine from cells from 7 of the 13 individuals and influenza A virus in 3 of 5 persons. Furthermore, Staph, aureus stimulated the BAL-cells to release leukotriene B4 in 7 of 11 subjects, whereas no release was found by influenza A virus in 7 examined persons. When cells from 4...... persons were stimulated with Staph. aureus no release of leukotriene C4 was found. The mediator release caused by bacteria and virus might be of importance for the exacerbation of bronchial asthma in upper respiratory tract infections, since histamine is assumed to increase the epithelial permeability...

  1. The effect of cysteine and sodium selenite on the toxicity of cadmium in staphylococcus aureus

    International Nuclear Information System (INIS)

    Cysteine was shown to have a protective effect on the killing rate caused by cadmium (Cd) but no effect on the uptake of Cd in S. aureus 3719-. The addition of 254x10-3 mmol/l of sodium selenite or more into the liquid growth medium increased the lag phase of growth of S. aureus 3719-. Sodium selenite had no protective effect on the toxicity of Cd in S.aureus 3719- as evaluated by the length of the lag phase of growth in the presence of Cd and varying amounts of sodium selenite. 534 x 10-6 mmol/l of sodium selenite in the growth medium had no effect on the uptake of Cd in S. aureus. (author)

  2. Non-spa-typeable clinical Staphylococcus aureus strains are naturally occurring protein A mutants

    DEFF Research Database (Denmark)

    Baum, Cathrin; Haslinger-Löffler, Bettina; Westh, Henrik; Boye, Kit; Peters, Georg; Neumann, Claudia; Kahl, Barbara C

    2009-01-01

    Staphylococcus aureus is a major human pathogen responsible for increasing the prevalence of community- and hospital-acquired infections. Protein A (SpA) is a key virulence factor of S. aureus and is highly conserved. Sequencing of the variable-number tandem-repeat region of SpA (spa typing......) provides a rapid and reliable method for epidemiological studies. Rarely, non-spa-typeable S. aureus strains are encountered. The reason for this is not known. In this study, we characterized eight non-spa-typeable bacteremia isolates. Sequencing of the entire spa locus was successful for five strains and...... revealed various mutations of spa, all of which included a deletion of immunoglobulin G binding domain C, in which the upper primer for spa typing is located, while two strains were truly spa negative. This is the first report demonstrating that nontypeability of S. aureus by spa sequencing is due either...

  3. Cyclic peptide inhibitors of the β-sliding clamp in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Kjelstrup, Susanne; Hansen, Paula Melo Paulon; Thomsen, Line Elnif; Hansen, Paul Robert; Løbner-Olesen, Anders

    2013-01-01

    Interaction between pairs of Staphylococcus aureus replication proteins was detected in an Escherichia coli based two-hybrid analysis. A reverse two-hybrid system was constructed for selection of compounds that hindered interaction between interacting protein pairs. A number of cyclic peptides, f...... minimum inhibitory concentration was ∼50 μg/ml for S. aureus cells. These compounds may serve as lead candidates for future development into novel classes of antibiotics as well as provide information on the function of the S. aureus replication process.......Interaction between pairs of Staphylococcus aureus replication proteins was detected in an Escherichia coli based two-hybrid analysis. A reverse two-hybrid system was constructed for selection of compounds that hindered interaction between interacting protein pairs. A number of cyclic peptides...

  4. Sterilization of Staphylococcus Aureus by an Atmospheric Non-Thermal Plasma Jet

    International Nuclear Information System (INIS)

    An atmospheric non-thermal plasma jet was developed for sterilizing the Staphylococcus aureus (S. aureus). The plasma jet was generated by dielectric barrier discharge (DBD), which was characterized by electrical and optical diagnostics. The survival curves of the bacteria showed that the plasma jet could effectively inactivate 106 cells of S. aureus within 120 seconds and the sterilizing efficiency depended critically on the discharge parameter of the applied voltage. It was further confirmed by scanning electron microscopy (SEM) that the cell morphology was seriously damaged by the plasma treatment. The plasma sterilization mechanism of S. aureus was attributed to the active species of OH, N2+ and O, which were generated abundantly in the plasma jet and characterized by OES. Our findings suggest a convenient and low-cost way for sterilization and inactivation of bacteria. (plasma technology)

  5. Fate of Staphylococcus aureus in radiation sterilized model food systems simulating dairy products

    International Nuclear Information System (INIS)

    Gamma irradiation was successfully employed for the development of sterile model food systems simulating dairy products such as pedha and cottage cheese which were inoculated with enterotoxigenic S.aureus S-6 and FR1-100 either individually or in association with S.epidermids and other mixed flora comprising of gram-positive, gram-negative and lactic bacteria and stored at 4 and 35 degC for 6-8 weeks. Pedha failed to support growth of S.aureus while cottage cheese favoured profuse growth of the pathogen. S.epidermidis exhibited a synergistic effect on the growth of S.aureus in cottage cheese. Baired-Parker's medium showed very poor recovery of S.aureus which necessitated the development of a new selective medium for the enumeration of staphylococci in processed foods. (author)

  6. Staphylococcus aureus and the ecology of the nasal microbiome

    DEFF Research Database (Denmark)

    Liu, Cindy M; Price, Lance B; Hungate, Bruce A; Abraham, Alison G; Larsen, Lisbeth A; Christensen, Kaare; Stegger, Marc; Skov, Robert; Andersen, Paal Skytt

    2015-01-01

    The human microbiome can play a key role in host susceptibility to pathogens, including in the nasal cavity, a site favored by Staphylococcus aureus. However, what determines our resident nasal microbiota-the host or the environment-and can interactions among nasal bacteria determine S. aureus...... colonization? Our study of 46 monozygotic and 43 dizygotic twin pairs revealed that nasal microbiota is an environmentally derived trait, but the host's sex and genetics significantly influence nasal bacterial density. Although specific taxa, including lactic acid bacteria, can determine S. aureus colonization......, their negative interactions depend on thresholds of absolute abundance. These findings demonstrate that nasal microbiota is not fixed by host genetics and opens the possibility that nasal microbiota may be manipulated to prevent or eliminate S. aureus colonization....

  7. Prevention of meticillin-resistant Staphylococcus aureus bloodstream infections in European hospitals: moving beyond policies

    NARCIS (Netherlands)

    Borg, M.A.; Hulscher, M.; Scicluna, E.A.; Richards, J.; Azanowsky, J.M.; Xuereb, D.; Huis, A. van; Moro, M.L.; Maltezou, H.C.; Frank, U.

    2014-01-01

    BACKGROUND: There is evidence that meticillin-resistant Staphylococcus aureus (MRSA) bacteraemia can be reduced with improved infection control and antibiotic stewardship. AIM: To survey infection control and antibiotic stewardship practices within European hospitals and to identify initiatives that

  8. Isolation and Identification of Vancomycin Resistant Staphylococcus aureus from Post Operative Pus Sample

    Directory of Open Access Journals (Sweden)

    Subhankari Prasad Chakraborty1, Santanu KarMahapatra1, Manjusri Bal2 and Somenath Roy1*

    2011-04-01

    Full Text Available Staphylococcus aureus is most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Recently, S. aureus have evolved resistance to both synthetic and traditional antibiotics. This study was carried out to isolate pathogenic S. aureus from post-operative pus sample, and VRSA was identified by evaluation of resistance patterns using conventional antibiotics. Thirty post operative pus samples were collected from nearby Hospital and species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc gene. Antibiotic susceptibility tests were carried out by MIC, MBC, DAD test and BHI vancomycin screening agar. VRSA were confirmed by PCR amplification of the vanA and vanB genes. From this study, it was observed that isolated S. aureus strains are pathogenic; 30% of strains were resistant to penicillin G, ampicillin and erythromycin; 26.67% strains were resistant to cephotaxime, gentamycin, streptomycin, tetracycline, chloramphenicol, norfloxacin, methicillin and vancomycin.

  9. Transmission of methicillin-resistant Staphylococcus aureus from food production animals to humans: a review

    NARCIS (Netherlands)

    Broens, E.M.; Cleef, van B.A.G.L.; Graat, E.A.M.; Kluytmans, J.A.J.W.

    2008-01-01

    International surveillance of antimicrobial use in food animal production shows that methicillinresistant Staphylococcus aureus (MRSA), traditionally a human pathogen associated with hospitals, has emerged in the community and animals. Since 1961, MRSA has been causing human infections in hospitals

  10. Study of the cell wall of Staphylococcus aureus and its sensitivity to enzybiotics

    OpenAIRE

    Čmelík, R. (Richard); Melková, K.; Kobzová, Š.; Janda, L

    2015-01-01

    The endolysin resistant and sensitive strains of Staphylococcus aureus were compared by means of LC-MS based structural analysis of peptidoglycan isolated from their cell walls. The structural explanation of the resistance was suggested.

  11. Diversity and evolution of blaZ from Staphylococcus aureus and coagulase-negative staphylococci

    DEFF Research Database (Denmark)

    Olsen, John E.; Christensen, Henrik; Aarestrup, Frank Møller

    2006-01-01

    NS) and Staphylococcus aureus of bovine origin. Methods: blaZ was detected in 143 strains of penicillin-resistant S. aureus and CoNS from five Danish cattle herds (n = 25/23), random CoNS isolates from Denmark (n = 37), a collection of S. aureus from six different countries (n = 52), humans in Denmark (n = 3) and beta...... types. The major types all contained strains of both human and bovine origin, and more than one Staphylococcus species, demonstrating a shared gene pool. In a comparison of S. aureus and CoNS obtained from five Danish cattle herds, the same type of blaZ was only detected in one case. Conclusions...

  12. Livestock Origin for a Human Pandemic Clone of Community-Associated Methicillin-Resistant Staphylococcus aureus

    DEFF Research Database (Denmark)

    Spoor, Laura E.; McAdam, Paul R.; Weinert, Lucy A.;

    2013-01-01

    -to-human host jumps by the major bovine S. aureus complex, CC97. Of note, one of the new clones was isolated from human infections on four continents, demonstrating its global dissemination since the host jump occurred over 40 years ago. The emergence of both human S. aureus clones coincided...... represent a reservoir for the emergence of new human-pathogenic S. aureus clones with the capacity for pandemic spread. These findings have major public health implications highlighting the importance of surveillance for early identification of emergent clones and improved transmission control measures......ABSTRACT The importance of livestock as a source of bacterial pathogens with the potential for epidemic spread in human populations is unclear. In recent years, there has been a global increase in community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections of healthy...

  13. Nigribactin, a Novel Siderophore from Vibrio nigripulchritudo, Modulates Staphylococcus aureus Virulence Gene Expression

    DEFF Research Database (Denmark)

    Nielsen, Anita; Månsson, Maria; Wietz, Matthias;

    2012-01-01

    Staphylococcus aureus is a serious human pathogen that employs a number of virulence factors as part of its pathogenesis. The purpose of the present study was to explore marine bacteria as a source of compounds that modulate virulence gene expression in S. aureus. During the global marine Galathea...... that 68 out of 83 marine bacteria (affiliated with the Vibrionaceae and Pseudoalteromonas sp.) influenced expression of S. aureus hla encoding α-hemolysin toxin and/or spa encoding Protein A. The isolate that upon initial screening showed the highest degree of interference (crude ethyl acetate extract......, enterobactin, failed to influence S. aureus virulence gene expression. This study shows that marine microorganisms produce compounds with potential use in therapeutic strategies targeting virulence rather than viability of human pathogens....

  14. Beta-lactamase detection in Staphylococcus aureus and coagulase-negative Staphylococcus isolated from bovine mastitis

    Directory of Open Access Journals (Sweden)

    Bruno F. Robles

    2014-04-01

    Full Text Available The objectives of the study were to evaluate the presence/production of beta-lactamases by both phenotypic and genotypic methods, verify whether results are dependent of bacteria type (Staphylococcus aureus versus coagulase-negative Staphylococcus - CNS and verify the agreement between tests. A total of 200 bacteria samples from 21 different herds were enrolled, being 100 CNS and 100 S. aureus. Beta-lactamase presence/detection was performed by different tests (PCR, clover leaf test - CLT, Nitrocefin disk, and in vitro resistance to penicillin. Results of all tests were not dependent of bacteria type (CNS or S. aureus. Several S. aureus beta-lactamase producing isolates were from the same herd. Phenotypic tests excluding in vitro resistance to penicillin showed a strong association measured by the kappa coefficient for both bacteria species. Nitrocefin and CLT are more reliable tests for detecting beta-lactamase production in staphylococci.

  15. PCR assay with host specific internal control forStaphylococcus aureus from bovine milk samples

    Directory of Open Access Journals (Sweden)

    Zafer Cantekin

    2015-03-01

    Full Text Available Staphylococcus aureus is considered as one of the most important and common pathogens of bovine mastitis. Polymerase Chain Reaction is frequently proposed in the diagnosis of S. aureus directly from milk samples instead of classical culture. However, false-negative results may occur in the polymerase chain reaction analysis performed directly from clinical material. For the purpose of disclosing the false negative results, the use of internal amplification controls can be beneficial. Therefore, in this study a new polymerase chain reaction technique with host specific internal amplification control was developed by optimizing S. aureus-specific primers in combination with bovine specific primers. The effectiveness of the developed technique in this study was attempted in milk samples from bovine subclinical mastitis. This technique has the potential to detect S. aureus from bovine milk samples or dairy products.

  16. Evaluation of a dry, rehydratable film method for rapid enumeration of Staphylococcus aureus.

    Science.gov (United States)

    Mach, P A; Lindberg, K G; Lund, M E

    2000-01-01

    Results with the new 3M Petrifilm Rapid S. aureus Count (RSA) Plate method were compared with those of the classical Baird-Parker agar (BPA) method for detection and enumeration of Staphylococcus aureus. Studies on 219 bacterial strains demonstrated that the Petrifilm RSA plate is more sensitive than and as specific as the classical BPA method for confirmed identification of S. aureus. Counts of colonies from 71 pure cultures, 61 naturally contaminated food samples, and more than 750 artificially inoculated food samples showed that the Petrifilm RSA method was as effective as the classical BPA method for identification and enumeration of S. aureus. The Petrifilm RSA method gave results in one-third the time required for the classical method. PMID:11048850

  17. Risk Factors for Methicillin Resistant Staphylococcus aureus Nasal Colonization of Healthy Children

    OpenAIRE

    Soltani, Babak; Abbas TAGHAVI ARDAKANI; Moravveji, Alireza; Erami, Mahzad; Haji Rezaei, Mostafa; Moniri, Rezvan; Namazi, Mansoor

    2014-01-01

    Background: Nasal colonization of healthy children with Staphylococcus aureus is an important risk factor for different infections. Detection of colonized individuals with methicillin resistant S. aureus (MRSA) and its eradication is the proper prevention strategy for infection spread in the community and health-care centers. Objectives: The aim of this study was to determine the prevalence, associated risk factors and antibiotic resistance pattern among healthy children who were nasal carrie...

  18. Prostaglandin E2 from Candida albicans Stimulates the Growth of Staphylococcus aureus in Mixed Biofilms

    Science.gov (United States)

    Krause, Jan; Geginat, Gernot; Tammer, Ina

    2015-01-01

    Background Previous studies showed that Staphylococcus aureus and Candida albicans interact synergistically in dual species biofilms resulting in enhanced mortality in animal models. Methodology/Principal Findings The aim of the current study was to test possible candidate molecules which might mediate this synergistic interaction in an in vitro model of mixed biofilms, such as farnesol, tyrosol and prostaglandin (PG) E2. In mono-microbial and dual biofilms of C.albicans wild type strains PGE2 levels between 25 and 250 pg/mL were measured. Similar concentrations of purified PGE2 significantly enhanced S.aureus biofilm formation in a mode comparable to that observed in dual species biofilms. Supernatants of the null mutant deficient in PGE2 production did not stimulate the proliferation of S.aureus and the addition of the cyclooxygenase inhibitor indomethacin blocked the S.aureus biofilm formation in a dose-dependent manner. Additionally, S. aureus biofilm formation was boosted by low and inhibited by high farnesol concentrations. Supernatants of the farnesol-deficient C. albicans ATCC10231 strain significantly enhanced the biofilm formation of S. aureus but at a lower level than the farnesol producer SC5314. However, C. albicans ATCC10231 also produced PGE2 but amounts were significantly lower compared to SC5314. Conclusion/Significance In conclision, we identified C. albicans PGE2 as a key molecule stimulating the growth and biofilm formation of S. aureus in dual S. aureus/C. albicans biofilms, although C. albicans derived farnesol, but not tyrosol, may also contribute to this effect but to a lesser extent. PMID:26262843

  19. Buah Mengkudu (Morinda citrifolia) Meningkatkan Respon Imun Mencit (Mus musculus) Terhadap Infeksi Bakteri Staphylococcus aureus

    OpenAIRE

    Mufidah Zumrotul

    2015-01-01

    Noni (Morinda citrifolia) Increase Immune Response in Mice (Mus musculus) Infected Staphylococcus aureus. Infection disease caused by bacteria is one of the illness in several developing countries including in Indonesia, with high mortality rate. Infection of  S. aureus as the cause of problem resistance for antibiotic or multi drug resistance are giving the therapy of drug itself with change to medical herbal. The aim of this study is known the role of M.citrifolia extract to increase immune...

  20. Sudden death caused by Staphylococcus aureus carrying Panton–Valentine leukocidin gene in a young girl

    OpenAIRE

    Trieu, Thanh-Van; Gaudelus, Joel; Lefevre, Sophie; Teychene, Anne Marie; Poilane, Isabelle; Colignon, Anne; Etienne, Jerome; de Pontual, Loïc

    2009-01-01

    Staphylococcus aureus carrying the Panton–Valentine leukocidin (PVL) gene could be the source of both recurrent furunculosis or abscesses and severe infections, mainly necrotising pneumonia. We present the case of a young girl from consanguineous parents who died suddenly. The postmortem examination revealed necrotising pneumonia due to a PVL producing Staphylococcus aureus strain, raising the question of the role of the host’s immune status in this infection.