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Cryptococcus spp isolated from dust microhabitat in Brazilian libraries
Diniz DPLJ Leite-Júnior, Janaína JVRSA Amadio, Evelin ERM Martins, Sara SAAS Sim?es, Ana Caroline ACAY Yamamoto, Fábio FALS Leal-Santos, Doracilde DTT Takahara, Rosane RCH Hahn
Journal of Occupational Medicine and Toxicology , 2012, DOI: 10.1186/1745-6673-7-11
Abstract: Eighty-four swab collections were performed on dust found on books in three libraries in the city of Cuiabá, state of Mato Grosso, Brazil. The material was seeded in Sabouraud agar and then observed for characteristics compatible with colonies with a creamy to mucous aspect; the material was then isolated in birdseed (Niger) agar and cultivated at a temperature of 37°C for 5 to 7?days. Identification of isolated colonies was performed by microscopic observation in fresh preparations dyed with India ink, additional tests performed on CGB (L-canavanine glycine bromothymol blue), urea broth, and carbohydrate assimilation tests (auxanogram).Of the 84 samples collected from book dust, 18 (21.4%) were positive for Cryptococcus spp totalizing 41 UFC’s. The most frequently isolated species was C. gattii 15 (36.6%); followed by C. terreus, 12 (29.3%); C. luteolus 4 (9.8%); C. neoformans, and C. uniguttulatus 3 (7.3%), and C. albidus and C. humiculus with 2 (4.6%) of the isolates.The high biodiversity of the yeasts of the Cryptococcus genus, isolated from different environmental sources in urban areas of Brazil suggests the possibility of individuals whose immune systems have been compromised or even healthy individuals coming into sources of fungal propagules on a daily bases throughout their lives. This study demonstrates the acquisition possible of cryptococcosis infection from dust in libraries.
Evaluación de varias técnicas de extracción de ADN de Cryptococcus spp. a partir de muestras ambientales
Casta?eda,Alexandra; McEwen,Juan; Hidalgo,Marylin; Casta?eda,Elizabeth;
Biomédica , 2004,
Abstract: the genus cryptococcus encompasses 38 species, but only 3 are associated with disease in humans and animals, cryptococcus laurentii, cryptococcus albidus and cryptococcus neoformans. the last one is the most frequently reported. the disease is acquired by the inhalation of infectious propagules present in the environment. the habitat has been established using extraction techniques with buffer supplemented with antibiotics and plating in selective media. the aim of this work was to evaluate several dna extraction techniques for cryptocococus spp . from environmental samples. the control isolates were c. neoformans, c. albidus, c. laurentii and paracoccidiodes brasiliensis. we also used vermiculita and soil samples contaminated with different yeast concentrations (10 to 10 6 cells/g) and samples naturally contaminated with c. neoformans. dna was extracted with physical and chemical methods and with a commercial kit, and the dna was purified with agarose blocks and silica columns. for the pcr amplification we used the cn4-cn5 primers, which are specific for c. neoformans. only the commercial kit allowed dna extraction and amplification from contaminated soil samples up to a concentration of 10 cells/g and from one sample naturally colonized. with this work we extracted and amplified dna from cryptococcus spp. from environmental samples with appropriate pcr specificity, it will be a tool to establish the ecological areas of c. neoformans in our country.
Unusual morphologies of Cryptococcus spp. in tissue specimens: report of 10 cases
Gazzoni, Alexandra Flávia;Oliveira, Flávio de Mattos;Salles, Emily Ferreira;Mayayo, Emilio;Guarro, Josep;Capilla, Javier;Severo, Luiz Carlos;
Revista do Instituto de Medicina Tropical de S?o Paulo , 2010, DOI: 10.1590/S0036-46652010000300006
Abstract: ten cases of cryptococcosis due to unusual microscopic forms of cryptococcus sp. observed over a twenty-eight year period (1981-2009) are presented. the most important clinicopathological and laboratory data are tabulated. the uncommon forms of cryptococcal cells given are: structures resembling germ tube (one case), chains of budding yeasts (one case), pseudohyphae (two cases) and nonencapsulated yeast-like organisms (eight cases). the diagnosis was based on the histopathological findings. the causative organism was isolated and identified in seven cases; five were due to c. neoformans, and two to c. gattii. in addition, the importance of using staining histochemical techniques - grocott's silver stain (gms), mayer's mucicarmine stain (mm) and fontana-masson stain (fm) - in the diagnosis of cryptococcosis is argued.
Sinergismo in vitro entre hidrazonas, ajoeno y posaconazol sobre aislados de Cryptococcus spp In vitro synergisms among hydrazones, ajoeno and posaconazole against Cryptococcus spp
Julio Vivas,Primavera Alvarado,Gonzalo Visbal,álvaro álvarez-Aular
Investigación Clínica , 2011,
Abstract: El objetivo de este trabajo fue estudiar la susceptibilidad in vitro de aislados de Cryptocococus spp con una nueva clase de antifúngicos, hidrazonas esteroidales y comparar su actividad antifúngica en combinación con ajoeno y posaconazol contra aislados de Cryptococcus spp. Se utilizaron tres aislados del género Cryptococcus 42794, 4050 y 44192 y se evaluaron su sensibilidad y efectos sinérgicos con las hidrazonas esteroidales, ajoeno y posaconazol, según el documento M27-A2 del CLSI. Se incluyeron las cepas Candida albicans (ATCC 90028) y Candida parapsilosis (ATCC 22019) como controles. Se observó con las hidrazonas (H1, H2, H3, H4) un efecto plateau a partir de 10 μM (CMI). Sin embargo, con la H4 se obtuvo bajo porcentaje de inhibición del crecimiento. Con el ajoeno, se obtuvieron valores de CMI de 25 y 50 μM. El posaconazol mostró altos valores de inhibición y un valor de CMI de 6 μM para 42794 y 44192 y un CMI de 20 μM para el aislado 4050. Se obtuvieron efectos sinérgicos al combinar posaconazol con ajoeno, ajoeno con hidrazona 3 y posaconazol con hidrazona 3. Los valores de concentración inhibitoria fraccional fueron de 0,24; 0,16 y 0,09 respectivamente, indicando un marcado efecto sinérgico. Se obtuvieron efectos sinérgicos importantes entre el posaconazol con ajoeno, ajoeno con hidrazona 3 y posaconazol con hidrazona 3, lo cual sería muy útil para futuros estudios clínicos. The aim of this study was to assess the in vitro susceptibility to novel antifungal compounds, the steroidal hydrazones, and to compare their antifungal activity and synergistic effects with other compounds, such as ajoeno and posaconazole on Cryptocococus spp isolates. Three Cryptococcus strains were used for this study (42794, 4050 and 44192) and their antifungal sensitivity and synergistic effects with ajoeno and posaconazole were evaluated according to the CLSI protocol number M27-A2. Candida albicans (ATCC 90028) and Candida parapsilosis (ATCC 22019) were used as controls. A plateau effect with hydrazones (H1, H2, H3, H4) was observed after 10 μM (CMI). However, with H4 only a mild inhibition on the growth was obtained. Combining hydrazone and ajoeno, CMI values between 25 and 50 μM were obtained. The highest inhibitions values were obtained with posaconazole and a CMI value of 6 μM for the strains 42794 and 44192, and a CMI value of 20 μM for the strain 4050. Synergy was observed combining posaconazole with ajoeno, ajoeno with hydrazone 3 and posaconazole with hydrazone 3. Fractional inhibitory concentrations were 0.24, 0.16 and 0.09 respectively, which might indicate
Primeira descri??o da caracteriza??o fenotípica e susceptibilidade in vitro a drogas de leveduras do gênero Cryptococcus spp isoladas de pacientes HIV positivos e negativos, Estado de Mato Grosso
Favalessa, Olivia Cometti;Ribeiro, Luciano Correa;Tadano, Tomoko;Fontes, Cor Jesus Fernandes;Dias, Flávio Basili;Coelho, Bruno Pereira Albuquerque;Hahn, Rosane Christine;
Revista da Sociedade Brasileira de Medicina Tropical , 2009, DOI: 10.1590/S0037-86822009000600010
Abstract: thirty-seven isolates from 10 hiv-negative and 26 hiv-positive patients in mato grosso were evaluated. direct examination, culturing and chemotyping of species were performed. ketoconazole, itraconazole, voriconazole, fluconazole and amphotericin b were evaluated. thirty-seven yeasts of cryptococcus spp were identified, of which 26 were from hiv-positive patients (25 cryptococcus neoformans and one cryptococcus gattii) and 10 from hiv-negative patients (five cryptococcus neoformans and five cryptococcus gattii). the cryptococcus neoformans clinical isolates from hiv-positive patients showed resistance (8% and 8.7%) and dose-dependent susceptibility (20% and 17.4%) to fluconazole and itraconazole, respectively. among the cryptococcus neoformans isolates from hiv-negative patients, there was dose-dependent susceptibility (40%) to fluconazole. cryptococcus gattii isolates from hiv-negative patients were shown to be susceptible to all antifungal agents, except for one isolate of cryptococcus gattii that showed dose-dependent susceptibility to fluconazole (20%). the cryptococcus gattii isolate from an hiv-positive patient showed resistance to fluconazole (mic > 256 ?g/ml) and itraconazole (mic = 3 ?g/ml).
Metodologia cientifica na forma??o do médico veterinário: experiência teórico-prática na análise de fontes urbanas de Cryptococcus spp -Jaboticabal, SP - Brasil
de Souza,José Gilberto; Candido,Regina Célia; Banzatto de Carvalho,Angela Cleusa de Fatima;
CES Medicina Veterinaria y Zootecnia , 2011,
Abstract: this article presents the results of an educational project for the scientific methodology degree course for veterinary medicine. the project was guided by the critical reflection on the necessity for the interaction between the theoretical and practical dimensions of professional training. an analysis was performed of urban sources of cryptococcus spp in excrements of pigeons (columbio, livia), indicating the need for education of the population about the risks factors of transmission and characterizing the pathogenicity of the identified agents in ten public places.
Biological control of Diatraea spp. (Lepidoptera: Pyralidae) in sugarcane crops in Central Venezuela
Weir L,Enrique H; Contreras,Williams; Gil de Weir,Karine;
Revista de Biología Tropical , 2007,
Abstract: entre los a?os 1990-1996, se evaluó la importancia de la mosca amazónica (melagonystilum minense) y de la avispa (cotesia flavipes) como controles biológicos de los perforadores de la ca?a de azúcar (diatraea saccharalis y diatraea rosa) en el centro de venezuela. durante el período de la zafra, seleccionamos aleatoriamente tallos de ca?a de azúcar que fueron abiertos para observar el número de perforaciones, hospedadores, proporción de hospedadores parasitados, proporción de hospedadores parasitados por la mosca amazónica o por la avispa. como consecuencia de las periódicas liberaciones de las moscas y las avispas criadas en el laboratorio, observamos una disminución pronunciada de la abundancia relativa de diatraea spp., pero no se obtuvo un efecto evidente de utilizar ambos parasitoides. la abundancia de diatraea spp. en presencia de ambos parasitoides fue similar a la observada durante los 45 a?os en que se utilizó únicamente m. minense como control biológico. sin embargo, m. minense probablemente sea el principal control biológico de esta plaga por ser más eficiente en la búsqueda de la misma y por ser un competidor más fuerte que c. flavipes.
Biological control of Diatraea spp. (Lepidoptera: Pyralidae) in sugarcane crops in Central Venezuela  [cached]
Enrique H Weir L,Williams Contreras,Karine Gil de Weir
Revista de Biología Tropical , 2007,
Abstract: Entre los a os 1990-1996, se evaluó la importancia de la mosca amazónica (Melagonystilum minense) y de la avispa (Cotesia flavipes) como controles biológicos de los perforadores de la ca a de azúcar (Diatraea saccharalis y Diatraea rosa) en el centro de Venezuela. Durante el período de la zafra, seleccionamos aleatoriamente tallos de ca a de azúcar que fueron abiertos para observar el número de perforaciones, hospedadores, proporción de hospedadores parasitados, proporción de hospedadores parasitados por la mosca amazónica o por la avispa. Como consecuencia de las periódicas liberaciones de las moscas y las avispas criadas en el laboratorio, observamos una disminución pronunciada de la abundancia relativa de Diatraea spp., pero no se obtuvo un efecto evidente de utilizar ambos parasitoides. La abundancia de Diatraea spp. en presencia de ambos parasitoides fue similar a la observada durante los 45 a os en que se utilizó únicamente M. minense como control biológico. Sin embargo, M. minense probablemente sea el principal control biológico de esta plaga por ser más eficiente en la búsqueda de la misma y por ser un competidor más fuerte que C. flavipes.
In vitro susceptibility to antifungal agents of environmental Cryptococcus spp. isolated in the city of Ribeir?o Preto, S?o Paulo, Brazil
Pedroso, Reginaldo dos Santos;Ferreira, Joseane Cristina;Candido, Regina Celia;
Memórias do Instituto Oswaldo Cruz , 2006, DOI: 10.1590/S0074-02762006000300002
Abstract: infections by cryptococcus strains other than c. neoformans have been detected in immunocompromised patients. of these strains, three are considered human pathogens: c. albidus, c. laurenttii, and c. uniguttulatus. this study deals with the in vitro susceptibility of cryptococcus to drugs such as amphotericin b, itraconazole, fluconazole, and 5-fluorocytosine. environmental cryptococcus isolates (50) distributed as follows: c. neoformans var. neoformans (16), c. albidus (17), c. laurentii (14), and c. uniguttulatus (3) were evaluated by the micro and macrodilution techniques, according to eucast and nccls recommendations, respectively. considering both methodologies the respective minimal inhibitory concentrations (mic) were 0.125 and 2 μg/ml for amphotericin b, 0.06 and 8 μg/ml for itraconazole, and 0.5 and more than 64 μg/ml for fluconazole and 5-fluorocytosine. agreement percentages for the two methodologies were 100% for amphotericin b and fluconazole for all the strains tested. for itraconazole, the agreement percentage was 81.3% in the c. neoformans strain and 100% for all the others. all species had a agreement percentage of 94.1 to 100% when susceptibility to 5-fluorocytosine was tested. it is concluded that environmental isolates of c. neoformans var. neoformans, c. albidus, c. laurentii, and c. uniguttulatus may show high mics against certain drugs, suggesting in vitro primary resistance to the antifungals tested.
Aislamiento de Cryptococcus gattii serotipo B a partir de detritos de Eucalyptus spp. en Colombia
Escandón,Patricia; Quintero,Elizabeth; Granados,Diana; Huérfano,Sandra; Ruiz,Alejandro; Casta?eda,Elizabeth;
Biomédica , 2005,
Abstract: introduction. cryptococcus gattii serotype b has been associated with several species of trees in tropical and subtropical regions. serotype b has been found to be the second most frequently isolated from patients in colombia, but it has not been isolated from the environment. therefore, a study was designed to sample plant material from a forest in the province of cundinamarca, with the aim of establishing the presence and distribution of the c. neoformans complex, specially serotype b. in addition, isolates were evaluated for several phenotypic characteristics associated with virulence. methodology. during february and march, 2003, 4 separate sample collections were made. one hundred sixty-seven samples were collected from detritus of eucalyptus and 28 samples from other species of trees. all were processed using the conventional procedure and plated on selective media. the following parameters were measured: cellular and capsular sizes in the filtrates, growth at 37°c, virulence in a mouse animal model system, and mating type as detected by pcr. results. cryptococcus gattii serotype b was isolated from 46 eucalyptus samples (27.5%). the cellular size in the filtrates ranged from 3.10 to 4.15 μm and the capsular size from 0.30 and 0.46 μm. the 46 isolates grew at 37°c, but none of them caused the death in the animals during 70-day observation period. all isolates were of mating type a. conclusions. this constitutes the first report of the isolation of serotype b, mating type a, from eucalyptus detritus in colombia.
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