ROSELI SANTOS DE FREITAS
Projetos de Pesquisa
Unidades Organizacionais
LIM/53 - Laboratório de Micologia, Hospital das Clínicas, Faculdade de Medicina
LIM/05 - Laboratório de Poluição Atmosférica Experimental, Hospital das Clínicas, Faculdade de Medicina
LIM/05 - Laboratório de Poluição Atmosférica Experimental, Hospital das Clínicas, Faculdade de Medicina
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- Fast and cost-effective protocol to produce Paracoccidioides spp. antigens(2023) FERNANDES-BERALDO, Karolina Rosa; FREITAS-XAVIER, Roseli Santos de; PARDINI-VICENTINI, AdrianaIntroduction. The existing methods for Paracoccidioides spp. antigen production are problematic in terms of standardization, specificity, stability, repeatability, and reproducibility.Objective. To optimize the methodology for Paracoccidioides spp. antigen production and evaluate its applicability in paracoccidioidomycosis immunodiagnosis.Materials and methods. The antigens were obtained from Paracoccidioides lutzii isolates (01, 66, and 8334), Paracoccidioides brasiliensis sensu stricto (113), and Paracoccidioides restripiensis (B-339). These fungi were grown at 36 degrees C +/- 1 degrees C, on modified Fava-Netto agar, according to Freitas et al. (2018). Paracoccidioides lutzii antigens were obtained after 5, 10, and 20 days of culture, whereas P. brasiliensis and P. restripiensis antigens were obtained after 10 days. Antigens were evaluated in natura, 10 and 20 times concentrated. Antigenic capacity was evaluated using a double immunodiffusion assay against serum samples from patients with paracoccidioidomycosis, histoplasmosis, and aspergillosis, and random blood donors.Results. Cross-reactivity between Paracoccidioides spp. antigens was observed when P. brasiliensis, P. restrepiensis antigens, and P. lutzii antigens were evaluated with the polyclonal antibodies against P. lutzii and P. brasiliensis, respectively. No cross-reactivity was obtained for polyclonal antibodies against Histoplasma capsulatum, Aspergillus fumigatus, and random blood donors. The proposed protocol allowed stable, repeatable, and reproducible genus-specific antigen production at a low cost and in a short cultivation time.Conclusion. The proposed protocol allowed us to obtain genus-specific antigens that can be developed and reproduced in all laboratories in Brazil and South America, where paracoccidioidomycosis is a neglected disease, contributing to an early diagnosis, especially in endemic regions, regardless of the species.
- Phenotypic and genotypic detection of Candida albicans and Candida dubliniensis strains isolated from oral mucosa of AIDS pediatric patients(2017) LIVERIO, Harisson Oliveira; RUIZ, Luciana da Silva; FREITAS, Roseli Santos de; NISHIKAKU, Angela; SOUZA, Ana Clara de; PAULA, Claudete Rodrigues; DOMANESCHI, CarinaThe aim of this study was to assess a collection of yeasts to verify the presence of Candida dubliniensis among strains isolated from the oral mucosa of AIDS pediatric patients which were initially characterized as Candida albicans by the traditional phenotypic method, as well as to evaluate the main phenotypic methods used in the discrimination between the two species and confirm the identification through genotypic techniques, i.e., DNA sequencing. Twenty-nine samples of C. albicans isolated from this population and kept in a fungi collection were evaluated and re-characterized. In order to differentiate the two species, phenotypic tests (Thermotolerance tests, Chromogenic medium, Staib agar, Tobacco agar, Hypertonic medium) were performed and genotypic techniques using DNA sequencing were employed for confirmation of isolated species. Susceptibility and specificity were calculated for each test. No phenotypic test alone was sufficient to provide definitive identification of C. dubliniensis or C. albicans, as opposed to results of molecular tests. After amplification and sequencing of specific regions of the 29 studied strains, 93.1% of the isolates were identified as C. albicans and 6.9% as C. dubliniensis. The Staib agar assay showed a higher susceptibility (96.3%) in comparison with other phenotypic techniques. Therefore, genotypic methods are indispensable for the conclusive identification and differentiation between these species.
- First report of tinea corporis caused by Arthroderma benhamiae in Brazil(2019) FREITAS, Roseli Santos de; FREITAS, Thais Helena Proenca de; SIQUEIRA, Lumena Pereira Machado; GIMENES, Viviane Mazo Favero; RENARD, GilArthroderma benhamiae is a zoophilic dermathophyte that can cause highly inflammatory tinea corporis and tinea capitis in humans. This is the first report of a patient with dermatophytosis caused by A. benhamiae in Brazil. The lesion was an erythematous, annular plaque on the lumbar region that appeared few weeks after playing with a street cat in a 19-month-old girl. Initial presumed diagnosis was tinea corporis caused by Microsporum canis. Topical treatments were ineffective and the patient required systemic treatment with griseofulvin. Mycological diagnosis was inconclusive: morphological differentiation between M. canis and Trichophyton benhamiae may be difficult, especially when the latter present yellow colonies. The etiological agent was identified only by ITS sequencing of the isolates aligned with reference strains to A. benhamiae. This report highlights the importance of ITS sequencing in the identification of isolates from some cases of dermatophytosis, because conventional morphological diagnosis may result in misdiagnosis of the agent and delay proper treatment.
- Identification of fungi species in the onychomycosis of institutionalized elderly(2013) VASCONCELLOS, Cidia; PEREIRA, Carolina Queiroz Moreira; SOUZA, Marta Cristina; PELEGRINI, Andrea; FREITAS, Roseli Santos; TAKAHASHI, Juliana PossatoBACKGROUND: Superficial fungal infections are caused by dermatophytes, yeasts or filamentous fungi. They are correlated to the etiologic agent, the level of integrity of the host immune response, the site of the lesion and also the injured tissue. OBJECTIVE: The purpose of this study is to isolate and to identify onychomycosis agents in institutionalized elderly (60 years old +). METHODS: The identification of the fungi relied upon the combined results of mycological examination, culture isolation and micro cultures observation under light microscopy from nail and interdigital scales, which were collected from 35 elderly with a clinical suspicion of onychomycosis and a control group (9 elderly with healthy interdigital space and nails). Both groups were institutionalized in two nursing homes in Sao Bernardo do Campo, SP, Brazil. RESULTS: The nail scrapings showed 51.40% positivity. Of these, dermatophytes were found in 44.40% isolates, 27.78% identified as Trichophyton rubrum and 5.56% each as Trichophyton tonsurans, Trichophyton mentagrophytes and Microsporum gypseum. The second more conspicuous group showed 38.89% yeasts: 16.67% Candida guilliermondii, 11.11% Candida parapsilosis, 5.56% Candida glabrata, and 5.56% Trichosporon asahii. A third group displayed 16.70% filamentous fungi, like Fusarium sp, Aspergillus sp and Neoscytalidium sp (5.56% each). The interdigital scrapings presented a positivity rate of 14.29%. The agents were coincident with the fungi that caused the onychomycosis. In the control group, Candida guilliermondii was found at interdigital space in one person. CONCLUSION: Employing a combination of those identification methods, we found no difference between the etiology of the institutionalized elderly onychomycosis from that reported in the literature for the general population.
- Fast protocol for the production of Histoplasma capsulatum antigens for antibody detection in the immunodiagnosis of histoplasmosis(2018) FREITAS, Roseli Santos de; KAMIKAWA, Camila Mika; VICENTINI, Adriana PardiniBackground: Current methods for the production of Histoplasma capsulatum antigens are problematic in terms of standardization, specificity, stability, repeatability and reproducibility. Aims: In this study, we sought to optimize the methodology for producing H. capsulatum antigens, and to evaluate its applicability. Methods: Antigenic preparations obtained from 12 H. capsulatum isolates were evaluated by double immunodiffusion and immunoblotting assays against homologous and heterologous sera. Results: The evaluated and optimized protocol allowed a more stable production, as well as repeatable, reproducible, with shorter culture time and less costly. By double immunodiffusion and immunoblotting assays, the best pattern of reactivity was observed for antigens obtained with 33 days of culture from the isolates 200 and 406 against the M antigen and for the isolate 200 with 15 days against H antigen. The SDS-PAGE presented antigenic components of molecular masses between 17 and 119 kDa. The immunoblotting sensitivity was 95.5% and 100% with histoplasmosis sera from ill patients and sera from H. capsulatum infected but otherwise healthy patients, respectively, to the antigen derived from isolates 200 and 406. Conclusions: We suggest the employment of the antigen from isolate 200, with 15 or 30 days of culture, in the double immunodiffusion and immunoblotting assays due to its good ability to discriminate both sera from patients with histoplasmosis illness and histoplasmosis infection, in addition to its high specificity against heterologous sera.
- Importance of the association of molecular and immunological diagnosis in immunocompetent patient with Histoplasma capsulatum and Cryptoccocus neoformans infection: a case report(2014) DANTAS, Katia Cristina; FREITAS, Roseli Santos de; GARCIA, Roberta Scholz Pinto; SILVA, Marcos Vinicius da; MURICY, Edna Cleide Mendes; KOHARA, Valdelene Sayuri; VICENTINI, Adriana PardiniThis case reports an immunocompetent 29-year-old woman with suspected pneumonia, suggestive of fungal infection. Immunoblotting analysis reactivity against Histoplasma capsulatum and Paracoccidioides brasiliensis were observed. Nested-PCR in blood employing species-specific primers was positive for H. capsulatum and Cryptococcus neoformans. The evaluation of paucisymptomatic patients with positive results for H. capsulatum and C. neoformans could be relevant for the prevention as well as the possible evaluation of the reactivated quiescent foci. In conclusion, the associated methodology may have contributed to the monitoring endogenous reactivation of these diseases.
- Oral colonization by Candida species in AIDS pediatric patients(2011) DOMANESCHI, C.; MASSARENTE, D. B.; FREITAS, R. S. de; MARQUES, H. H. de Sousa; PAULA, C. R.; MIGLIARI, D. A.; ANTUNES, J. L. F.The aim of this study was to assess the prevalence of factors associated with oral colonization by Candida spp. in pediatric patients with AIDS. The sample comprised of 117 children. Clinical status, medicines in use, and laboratory findings were obtained from hospital records; sociodemographic data were given by relatives. A dental examination assessed the prevalence of dental caries. The prevalence of oral colonization by Candida was 62%. Only seven children presented clinical manifestation of oral candidosis despite their high viral load index and low-for-age CD4 count. Candida colonization was directly associated with frequent use of antibiotics (prevalence ratio [PR] = 1.44), sulfa drugs (PR = 1.23), alteration in the oral mucosa (PR = 1.55), and untreated dental caries (PR = 1.93). It was inversely associated with the use of antiretroviral therapies (PR = 0.65). Candida albicans was the most frequently detected species (80%); phenotypic tests did not detect C. dubliniensis strains. This study observed a low prevalence of Candida-related oral lesions in these patients, which is compatible with the hypothesis that antiretroviral medicines may have contributed to reducing oral manifestations from Candida infection. The high prevalence of Candida colonization in HIV+/AIDS children with untreated dental caries reinforces the importance of oral health care in interdisciplinary health units that assist these patients.
- The use of nested Polymerase Chain Reaction (nested PCR) for the early diagnosis of Histoplasma capsulatum infection in serum and whole blood of HIV-positive patients(2013) DANTAS, Katia Cristina; FREITAS, Roseli S.; MOREIRA, Adriana Pardini Vicentini; SILVA, Marcos Vinicius da; BENARD, Gil; VASCONCELLOS, Cidia; CRIADO, Paulo RicardoThe aim of the study was to detect the rDNA sequences and their regions in Histoplasma capsulatum, which could be considered species-specific and used as a molecular method for this diagnosis by the technique of nested polymerase chain reaction (nested PCR), employing specific sequences (primers) for H. capsulatum: 18S rDNA region (HC18), 100 kDa (HC100) and the sequence 5.8 S-ITS rDNA (HC5.8). The PCR sequences HC18, HC100 and HC5.8 resulted in a specificity of 100%. The molecular assays may increase the specificity, sensitivity and speed in the diagnosis of Histoplasmosis.
- Investigation of superficial mycosis in cutaneous allergy patients using topical or systemic corticosteroids(2017) FREITAS, Roseli S. de; NEVES, Paula S.; CHARBEL, Cecilia E.; CRIADO, Paulo R.; NUNES, Ricardo S.; SANTOS-FILHO, Antonio M.; VASCONCELLOS, Cidia
- Evaluating VITEK MS for the identification of clinically relevant Aspergillus species(2020) AMERICO, Fernanda M.; SIQUEIRA, Lumena P. Machado; NEGRO, Gilda Maria B. Del; GIMENES, Viviane M. Favero; TRINDADE, Mario Roberto S.; MOTTA, Adriana L.; FREITAS, Roseli Santos de; ROSSI, Flavia; COLOMBO, Arnaldo L.; BENARD, Gil; ALMEIDA JUNIOR, Joao N. deAspergillus spp. identification has become more relevant in clinical practice since azole-resistant cryptic species have been related to invasive fungal infections. Conventional morphologic identification is not able to discriminate Aspergillus species, and DNA sequencing is not feasible for clinical laboratories. MALDI-TOF mass spectrometry is an emergent technology that has been explored to provide fast and accurate identification of microorganisms, including clinically relevant moulds. However, only a few studies have explored the platform VITEK MS for the identification of Aspergillus species. Hence, we provided additional data regarding the performance of the VITEK MS system for the identification of Aspergillus species, including azole-resistant ones. We also improved the RUO system by adding additional spectral profiles from well-identified Aspergillus strains belonging to different noncryptic and cryptic species. The IVD library correctly identified 91.6% of the organisms at genus and section level, and 84.7% at species level, including the azole-resistant Aspergillus lentulus and Aspergillus calidoustus. The organisms belonging to Aspergillus cryptic species had only 31.2% of correct species identification. The RUO library plus our in-house SuperSpectra correctly identified 100% of the organisms at genus and section level and 91.6% at species level. Among organisms belonging to Aspergillus cryptic species, 68.7% had correct species identification. Some closely related Aspergillus cryptic species showed similar spectral profiles and were difficult to be differentiated.