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.

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.

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.

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 10 min. 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.