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Previous issue date: 2011-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Despite Candida species are often human commensals isolated from various oral sites such as: tongue, cheek and palatal mucosa plus subgingival region, there are some properties linked to the organism commonly known as virulence factors which confer them the ability to produce disease. Oral candidiasis is one of the main oral manifestations reported in literature related to kidney transplant patients. The objectives of the present study were to identify and investigate virulence factors of yeasts isolated from the oral cavity of kidney transplant recipients admitted at the Hospital Universit?rio Onofre Lopes, in Natal RN. Seventy Candida species isolated from 111 kidney transplant recipients were investigated in this study. Identification of the isolates was performed by using the evidence of germ tube formation, hypertonic broth, tolerance to grow at 42?C, micromorphology and biochemical profiles. We observed a high rate of isolation of yeasts from the oral cavity of kidney transplant recipients (63.1%) being C. albicans was the most prevalent species. Oral candidiasis was diagnosed in 14.4% of transplant recipients. We evaluated virulence properties of the isolates regarding to: biofilm formation on polystyrene microplates as well as XTT reduction, adherence to acrylic resin and human buccal epithelial cells and proteinase activity. Most isolates were able to form biofilm by the method of adhesion to polystyrene. All isolates of Candida spp. remained viable during biofilm formation when analyzed by the method of XTT reduction. The number of CFU attached to the acrylic resin suggested high adherence for C. parapsilosis. C. albicans isolates showed higher median adherence to human buccal epithelial cells than non-C. albicans Candida isolates. Nevertheless, this difference was not statistically significant. C. dubliniensis showed low ability to adhere to plastic and epithelial cells and biofilm formation. Proteolytic activity was observed for all the isolates investigated, including the unique isolate of C. dubliniensis. There was a statistically significant association between proteinase production and the presence of oral candidiasis. Studies related to oral candidiasis in renal transplant recipients are limited to clinical and epidemiological data, but investigations concerning Candida spp. virulence factor for this group of individuals are still scarce. We emphasize the importance of studies related to virulence factors of yeasts isolated from this population to contribute to the knowledge of microbiological aspects of oral candidiasis / Apesar das leveduras do g?nero Candida serem frequentemente comensais humanos, isoladas de diferentes s?tios orais, incluindo l?ngua, mucosa jugal, mucosa palatal e regi?o subgengival, existem algumas propriedades ligadas a Candida spp., comumente denominadas fatores de virul?ncia, que lhes conferem a capacidade de produzir doen?a. Candid?ase bucal ? uma das principais manifesta??es orais citadas na literatura em rela??o aos pacientes transplantados renais. O objetivo deste estudo foi realizar identifica??o e avaliar os fatores de virul?ncia de leveduras isoladas da cavidade bucal de receptores de transplante renal que s?o acompanhados no Hospital Universit?rio Onofre Lopes, na cidade do Natal RN. Foram utilizadas 70 leveduras do g?nero Candida isoladas de 111 receptores de transplante renal. A identifica??o dos isolados foi realizada atrav?s das provas de forma??o de tubo germinativo, caldo hipert?nico, toler?ncia ? temperatura de 42?C, an?lise da micromorfologia e perfil bioqu?mico das leveduras. Observamos elevado ?ndice de isolamento de leveduras na cavidade bucal dos receptores de transplante renal (63,1%), havendo predom?nio de C. albicans. Candid?ase bucal foi diagnosticada em 14,4% dos transplantados. Avaliou-se o potencial de virul?ncia das leveduras atrav?s da forma??o de biofilme pelo m?todo de ader?ncia a microplaca de poliestireno, redu??o do XTT, habilidade de ader?ncia a corpos de prova de resina acr?lica e a c?lulas epiteliais bucais, bem como atividade de proteinase. A maioria dos isolados foi capaz de produzir biofilme pelo m?todo de ader?ncia ao poliestireno, determinada atrav?s de leitura em espectrofot?metro. Todos os isolados de Candida spp. permaneceram vi?veis durante a forma??o do biofilme pelo m?todo da redu??o do XTT. A contagem do n?mero de UFC aderidas ao corpo de prova demonstrou alta capacidade de ader?ncia de C. parapsilosis. Os isolados de C. albicans apresentaram maior mediana de ades?o ? c?lula epitelial bucal humana do que os isolados de C. n?o-C. albicans, contudo essa diferen?a n?o foi estatisticamente significativa. C. dubliniensis apresentou baixa capacidade de ader?ncia ao pl?stico e c?lulas epiteliais e forma??o do biofilme. Observamos atividade proteol?tica em todos os isolados pesquisados, inclusive o isolado de C. dubliniensis, e associa??o estatisticamente significativa entre a produ??o de proteinase e a presen?a de candid?ase bucal. Estudos relacionados ? candid?ase bucal em receptores de transplante renal limitam-se ? investiga??o de aspectos cl?nicos e epidemiol?gicos, n?o havendo dados concernentes a fatores de virul?ncia. Ressaltamos a import?ncia da realiza??o de estudos relacionados aos fatores de virul?ncia de leveduras isoladas nessa popula??o, a fim de que se aprofunde o conhecimento dos aspectos microbiol?gicos da candid?ase bucal / 2020-01-01
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/13467 |
| Date | 25 February 2011 |
| Creators | Diniz, Mariana Guimar?es |
| Contributors | CPF:70337950415, http://lattes.cnpq.br/2501015206371302, Oliveira, Maria Tereza Barreto de, CPF:20256680400, http://lattes.cnpq.br/9595939591405313, Brilhante, Raimunda S?mia Nogueira, CPF:70399573372, http://lattes.cnpq.br/4766125121792218, Milan, Eveline Pipolo |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Ci?ncias Farmac?uticas, UFRN, BR, Bioan?lises e Medicamentos |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/embargoedAccess |
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