Molecular identification of Pichia guilliermondii, Debaryomyces hansenii and Candida palmioleophila

Traditional phenotypic methods and commercial kits based on carbohydrate assimilation patterns are unable to consistently distinguish among isolates of Pichia guilliermondii, Debaryomyces hansenii and Candida palmioleophila. As result, these species are often misidentified. In this work, we established a reliable method for the identification/differentiation of these species. Our assay was validated by DNA sequencing of the polymorphic region used in a real-time PCR assay driven by species-specific probes targeted to the fungal ITS 1 region. This assay provides a new tool for pathogen identification and for epidemiological, drug resistance and virulence studies of these organisms

Avaliação da microbiota bucal de pacientes com anorexia nervosa e bulimia nervosa

Os Transtornos alimentares (TA) como Anorexia Nervosa (AN) e Bulimia Nervosa (BN) são acompanhados de inúmeras alterações sistêmicas e bucais relacionadas ao comprometimento do estado nutricional e às práticas compensatórias inadequadas para o controle do peso. O objetivo deste estudo foi avaliar diversidade microbiológica existente na cavidade bucal de pacientes com estes transtornos, por meio de técnicas de cultivo e utilizando métodos moleculares independentes de cultivo. Foram incluídos no estudo 32 pacientes anoréxicos e 27 bulímicos, pareados com 59 indivíduos controle. Amostras de enxágüe bucal foram semeadas para a avaliação da prevalência de leveduras do gênero Candida, estafilococos, enterococos, estreptococcos do grupo mutans (EGM), lactobacilos, enterobactérias/pseudomonas. Espécies de Candida, estafilococos, enterococos, enterobactérias/pseudomonas foram identificadas pelo sistema API. Amostras de biofilme supragengival foram coletadas e utilizadas somente nos procedimentos moleculares. As contagens de microrganismos nos grupos foram comparadas por ANOVA/Mann-Whitney (5%). Houve diferença estatisticamente significantes (p<0,05) para as contagem de leveduras do gênero Candida, estafilococos, enterococos, EGM e lactobacilos entre o grupo TA e controle, mas não houve diferenças significativas para a prevalência de enterobactérias/pseudomonas (p=0,312). Pequena diferença entre os grupos foi observada na diversidade de espécies dos microrganismos estudados pelo método de cultivo. Avaliação molecular foi realizada pela ribotipagem por seqüenciamento do 16S rRNA bacteriano e regiões D1/D2 do 28S rRNA. Foram avaliados cerca de 3000 clones do grupo TA e 1500 clones do controle. Sessenta e duas espécies ou filotipos de bactérias foram detectados...Eating disorders such as nervous Anorexia and Bulimia Nervosa have several clinical and oral alterations related to the nutritional state involvement and the inadequate compensatory practices for weight control. The aim of this study was to evaluate the microbial diversity in the oral cavity of patients with Anorexia Nervosa and Bulimia nervosa by cultivation techniques and cultivationindependent molecular methods. The study included 32 patients and 27 bulimic anorexics, matched with 59 control subjects. Oral rinse samples were cultured to assess the prevalence of Candida species, staphylococci, enterococci, streptococci mutans (EGM), lactobacilli, Enterobacteriaceae / Pseudomonas. Candida species, staphylococci, enterococci, Enterobacteriaceae / Pseudomonas were identified by API systems. Supragingival biofilm samples were collected and used only in molecular procedures. Counts of microorganisms in the groups were compared by ANOVA / Mann-Whitney (5%). There was a statistically significant (p <0.05) for the counting of yeasts, staphylococci, enterococci, and lactobacilli EGM between TA and control groups, but there were no significant differences in the prevalence of Enterobacteriaceae / Pseudomonas (p = 0.312). Few differences between the groups were observed in the species diversity of organisms studied by the method of cultivation. Molecular analysis was performed by ribotyping by sequencing the 16S rRNA bacterial and D1/D2 regions of 28S rRNA. About 3000 clones of the TA group and 1500 clones of control were evaluated. Sixty-two species or filotypes of bacteria were detected, with 22 identifications were found only in the study group, only 6 in the control group and 34 in both groups. Microorganisms related to caries and periodontal diseases... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Presença de Candida, staphylococcus, enterobacteriaceae e pseudomonadaceae na cavidade bucal de pacientes HIV positivos

Alterações na microbiota bucal podem ocorrer na vigência de doenças sistêmicas e durante o tratamento destas, ocasionando superinfecções. Reservatórios bucais de patógenos potenciais, como Candida, Staphylococcus, Enterobacteriaceae e Pseudomonadaceae podem ocasionar infecções bucais ou sistêmicas e comprometer a vida de pacientes imunossuprimidos. Desta forma, o objetivo deste estudo foi avaliar a presença de microrganismos dos gêneros Candida e Staphylococcus e das famílias Enterobacteriaceae e Pseudomonaceae na cavidade bucal e sítios periodontais de indivíduos HIV positivos. Foram estudados 45 pacientes HIV positivos e 45 indivíduos sistemicamente saudáveis com perfil semelhante aos HIV positivos. Enxágües bucais e amostras de sítios periodontais foram obtidos e a partir destes foi realizada avaliação da prevalência dos microrganismos e identificação fenotípica dos isolados. As contagens de microrganismos dos grupos HIV e controle foram comparados estatisticamente pelo teste de Mann-Whitney (5%). As contagens dos microrganismos nos pacientes HIV positivos fumantes e não fumantes foram comparadas pelo teste Mann-Whitney (5%), não havendo diferença estatisticamente significativa. Concluiu-se que o grupo HIV apresentou maior prevalência de Candida spp. e Enterobacteriaceae/Pseudomonaceae e maior diversidade de espécies em relação ao grupo controle.Changes in the oral microflora may occur during the occurrence of systemic diseases and during their treatment leading to superinfections. Oral reservoirs of potential pathogens, such as enteric bacteria, staphylococci and Candida, may cause oral or systemic diseases and threaten the life of immunocompromised patients. In this way, the aim of this study was to evaluate the presence of microorganisms of Candida and Staphylococcus genus and Enterobacteriaceae and Pseudomonadaceae families in the oral cavity and periodontal sites of HIV positive patients. Forty-five HIV positive patients and 45 systemically healthy individuals with similar profile in relation to HIV positive ones were included. Oral rinses and samples from the periodontal sites were collected and the evaluation of microorganisms prevalence and phenotypic identification of the isolates were performed. Counts of microorganisms between HIV-positive smokers and not-smokers patients were compared (Mann-Whitney, 5%) and no statistically significant differences were observed. It could be concluded that HIV group presented higher prevalence of Candida spp. and Enterobacteriaceae/Pseudomonadaceae and higher diversity of species in relation to the control group.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Evaluation of alternative methods for the disinfection of toothbrushes

The aim of this study was to evaluate alternative methods for the disinfection of toothbrushes considering that most of the previously proposed methods are expensive and cannot be easily implemented. Two-hundred toothbrushes with standardized dimensions and bristles were included in the study. The toothbrushes were divided into 20 experimental groups (n=10), according to microorganism considered and chemical agent used. The toothbrushes were contaminated in vitro by standardized suspensions of Streptococcus mutans, Streptococcus pyogenes, Staphylococcus aureus or Candida albicans. The following disinfectants were tested: 0.12% chlorhexidine digluconate, 50% white vinegar, a triclosan-containing dentifrice solution, and a perborate-based tablet solution. The disinfection method was immersion in the disinfectant for 10min. After the disinfection procedure, the number of remaining microbial cells was evaluated. The values of cfu/toothbrush of each group of microorganism after disinfection were compared by Kruskal-Wallis ANOVA and Dunn's test for multiple comparisons (5%). The chlorhexidine digluconate solution was the most effective disinfectant. The triclosan-based dentifrice solution promoted a significant reduction of all microorganisms' counts in relation to the control group. As to the disinfection with 50% vinegar, a significant reduction was observed for all the microorganisms, except for C. albicans. The sodium perborate solution was the less effective against the tested microorganisms. Solutions based on triclosan-containing dentifrice may be considered effective, nontoxic, cost-effective, and an easily applicable alternative for the disinfection of toothbrushes. The vinegar solution reduced the presence of S. aureus, S. mutans and S. pyogenes on toothbrushes

Evaluation of gene expression SAP5, LIP9, and PLB2 of candida albicans biofilms after photodynamic inactivation

With the increasing number of strains of Candida ssp. resistant to antifungal agents, the accomplishment of researches that evaluate the effects of new therapeutic methods, like photodynamic inactivation (PDI), becomes important and necessary. Thus, the objective of this study was to verify the effects of the PDI on Candida albicans biofilms, evaluating their effects on the expression of the gene hydrolytic enzymes aspartyl proteinase (SAP5), lipase (LIP9), and phospholipase (PLB2). Clinical strains of C. albicans (n = 9) isolated from patient bearers of the virus HIV and a pattern strain ATCC 18804 were used. The quantification of gene expression was related to the production of hydrolytic enzymes using the quantitative polymerase chain reaction (qPCR) assay. For PDI, we used laser-aluminum-gallium arsenide low power (red visible, 660 nm) as a light source and the methylene blue at 300 mu M as a photosensitizer. We assessed two experimental groups for each strain: (a) PDI: sensitization with methylene blue and laser irradiation and (b) control: without sensitization with methylene blue and light absence. The PDI decreased gene expression in 60 % of samples for gene SAP5 and 50 % of the samples decreased expression of LIP9 and PLB2. When we compared the expression profile for of each gene between the treated and control group, a decrease in all gene expression was observed, however no statistically significant difference (Tukey&apos;s test/p = 0.12). It could be concluded that PDI (photosensitization with methylene blue followed by low-level laser irradiation) showed a slight reduction on the expression of hydrolytic enzymes of C. albicans, without statistical significance.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

In vitro antifungal susceptibility of Candida spp. oral isolates from HIV-positive patients and control individuals

Oropharyngeal candidiasis is the most common fungal infection among HIV-positive patients. This condition can be treated with either systemic or topical antifungal agents; treatments are usually indicated empirically on the basis of clinical data. The knowledge of in vitro antifungal susceptibility is important to determine correct therapeutic guides for the treatment of fungal infections. Therefore, the objective of this study was to determine the antifungal susceptibility profile of oral Candida isolates from HIV-positive patients and control individuals. Amphotericin B, fluconazole, flucytosine, nystatin and ketoconazole were tested according to the methodology of microdilution proposed by the Clinical and Laboratory Standards Institute (CLSI); results were recorded in values of minimal inhibitory concentration (MIC). A total of 71 Candida isolates from HIV-positive patients were examined with the following species represented: C. albicans (59), C. tropicalis (9), C. glabrata (1), C. guilliermondii (1) and C. krusei (1). A total of 15 Candida isolates were evaluated from control individuals comprised of 11 C. albicans and 4 C. tropicalis samples. Our results demonstrated that the tested antifungal agents showed good activity for most isolates from both groups; however, variability in MIC values among isolates was observed

Opportunistic microorganisms in patients undergoing antibiotic therapy for pulmonary tuberculosis

Antimicrobial therapy may cause changes in the resident oral microbiota, with the increase of opportunistic pathogens. The aim of this study was to compare the prevalence of Candida, Staphylococcus, Pseudomonas and Enterobacteriaceae in the oral cavity of fifty patients undergoing antibiotic therapy for pulmonary tuberculosis and systemically healthy controls. Oral rinsing and subgingival samples were obtained, plated in Sabouraud dextrose agar with chloramphenicol, mannitol agar and MacConkey agar, and incubated for 48 h at 37ºC. Candida spp. and coagulase-positive staphylococci were identified by phenotypic tests, C. dubliniensis, by multiplex PCR, and coagulase-negative staphylococci, Enterobacteriaceae and Pseudomonas spp., by the API systems. The number of Candida spp. was significantly higher in tuberculosis patients, and C. albicans was the most prevalent specie. No significant differences in the prevalence of other microorganisms were observed. In conclusion, the antimicrobial therapy for pulmonary tuberculosis induced significant increase only in the amounts of Candida spp.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Prevalence and antifungal resistance profile of Candida spp. oral isolates from patients with type 1 and 2 diabetes mellitus

Objective: The goal of the study was to measure the prevalence of Candida spp. in the oral cavity of patients with diabetes types 1 and 2 when compared to healthy individuals and to study antifungal resistance profile of the isolates.Design: There were 162 subjects in the study: diabetes type 1 (n = 39); control group 1 (n = 50): healthy individuals matched in gender, age, and oral conditions to diabetes type 1 patients; diabetes type 2 (n = 37); control group 2 (n = 36) who were matched to each patient of the diabetes type 2 group. Stimulated saliva was collected and isolates were identified with phenotypic tests. The presence of C. dubliniensis was determined by multiplex PCR.Results: There were no statistically significant differences in Candida spp. frequency between the diabetes 1 group and its control (p = 0.443) nor between the diabetes 2 group and its control (p = 0.429). C. albicans was the most frequently isolated yeast in all groups. In the diabetes groups, C. stellatoidea, C. parapsilosis, C. tropicalis, C. lipolytica, C. glabrata, and C. krusei were also identified. Additionally, in control groups, C. kefyr was also detected. None of the isolates were resistant to amphotericin B and flucytosine. A low percentage of the isolates were resistant to ketoconazole.Conclusions: No differences were detected in colonization of Candida spp. oral isolates from type 1 and type 2 diabetes when compared to matched controls. The antifungal resistance of Candida spp. isolates for ketoconazole from type 1 diabetes patients was significantly higher than that of its matched control. (C) 2010 Published by Elsevier Ltd.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP