104 research outputs found
Freqüência de Candida sp. em biópsias de lesões da mucosa bucal
Candidosis is the most common fungal infection in the oral cavity, and is usually associated with local and systemic predisposing factors. The ocurrence and relevance of Candidal infection in oral lesions such as liquen planus, leukoplakias and carcinomas are still to be understood. The aim of the present study was to define the frequency of infection by Candida sp. on biopsies of oral mucosal lesions and associate its presence with malignant and dysplastic lesions. Histopathology reports issued between 1990 and 2001 inclusive were reviewed. Three sections of each mucosal biopsy were stained using the periodic acid-Schiff (PAS) technique. From the 832 biopsies 27.2% were PAS positive, of which 83.25% were obtained from male patients. There was positive association between fungic infection and mild, moderate and severe epithelial dysplasia, squamous cell carcinoma and hiperqueratosis (p < 0.05). There was no association between fungic infection and inflammatory fibrous hyperplasia, hyperkeratosis, lichen planus and pyogenic granuloma (p < 0.05). The frequency of infection in the tongue was significantly higher (p < 0.05) than in the other sites. Our results do not show a causal relation between Candida sp. and dysplastic lesions and carcinomas, but do confirm the higher presence of that microrganism in those lesions.O objetivo desse trabalho foi determinar a freqüência da infecção por Candida sp. em biópsias de lesões da mucosa bucal, assim como associar a presença de Candida sp. com lesões malignas e lesões com vários graus de displasia. Foram utilizadas 832 biópsias da mucosa bucal, previamente incluídas em parafinas, cujos blocos foram obtidos dos arquivos da Disciplina de Patologia da Faculdade de Odontologia de Araraquara da UNESP, no período entre 1990-2001. Três cortes seqüenciais foram corados pelo ácido periódico de Schiff (PAS). Do total de biópsias 27,2% foram PAS positivas, dessas 83,25% eram provenientes de pacientes do sexo masculino. Houve associação positiva entre infecção com displasia epitelial leve, moderada, severa, carcinoma espinocelular e hiperqueratose (p < 0,05). Não houve associação entre hiperplasia fibrosa inflamatória, líquen plano, granuloma piogênico (p < 0,05) com infecções fúngicas. A língua foi o sítio mais acometido por infecções em relação a outros sítios (p < 0,05). A partir dos dados quantitativos, concluiu-se que houve correlação positiva de infecção por fungos, lesões displásicas e carcinoma, sendo mais freqüente no sexo masculino. Estes dados não permitem inferir se o fungo causa displasia epitelial e carcinoma, mas confirmam a maior presença de Candida nessas lesões
Quantitative evaluation of Streptococcus mutans and Candida sp and salivary factors in the oral cavity of patients submitted to radiotherapy
O objetivo deste trabalho foi analisar quantitativamente os microrganismos, Streptococcus do grupo mutans e Candida sp, da cavidade bucal de pacientes com carcinoma de orofaringe antes, durante e após o tratamento com radioterapia e correlacionar fatores salivares como pH, capacidade tampão (CT) e fluxo salivar (FS). Amostras de saliva foram coletadas, diluídas e inoculadas em ágar SB-20 e ágar Sabouraud, respectivamente para Streptococcus do grupo mutans e Candida sp. Previamente à diluição, a saliva concentrada foi analisada, determinando-se os fatores salivares. Após crescimento das colônias, o número de microrganismos foi determinado em UFC/ml. A análise dos resultados permitiu concluir que houve correlação positiva entre os fatores salivares e a presença de microrganismos ilustrada pelo aumento no número de UFC/ml dos microrganismos analisados concomitantemente com a diminuição do fluxo salivar. Os efeitos da radiação comprometeram a homeostasia salivar e favoreceram o aumento das infecções por leveduras e bactérias durante o tratamento radioterápico.The aim of this study was to quantify the microorganisms Streptococcus mutans and Candida sp in the oral cavity of patients with oropharynx carcinoma, before, during and after radiotherapy, and to correlate the results with salivary factors such as pH, buffer capacity (CT) and flow rate (FS). Saliva samples were collected, diluted and inoculated in SB-20 agar and in Sabouraud agar, for Streptococcus mutans and Candida sp, respectively. Previously to dilution, the concentrated saliva was analyzed, and the salivary factors were determined. After the growth of colonies, the number of microorganisms was determined in CFU/ml. The analysis of the results allowed to conclude that the salivary factors are related to the presence of microorganisms, and that the number of CFU/ml increased as salivary flow rate decreased. The effects of radiation compromised salivary homeostasis and favored the increase of infection by yeasts and bacteria
Atividade anti fúngica do α-terpinen sobre Candida albicans
Objetivo: avaliar a atividade antifúngica do α- terpinen sobre culturas planctonicas e biofi lme de Candida albicans. Material e Métodos: Primeiramente, foi determinada a Concentração Inibitória Mínima (CIM) e a Concentração Fungicida Mínima (CFM) do α-terpinen sobre microrganismos planctônicos. A Nistatina foi utilizada como controle positivo. Biofi lme de Candida albicans foi desenvolvido e, após o tratamento com diferentes concentrações de α-terpinen, foi quantifi cado em UFC/mL, além da atividade metabólica das células ser avaliada por XTT. Resultados: a menor concentração capaz de inibir o crescimento (CIM) foi 0,2 % para o α-terpinen e 4 μg/mL para a Nistatina. Na CIM, os resultados mostraram que a partir da concentração 0,05 % de α-terpinen e 2 μg/mL de Nistatina houve diminuição de C.albicans quando comparado ao controle. A CFM foi para α-terpinen 0,2 % e Nistatina 8 μg/mL. Na quantifi cação as concentrações efi cazes foram de α-terpinen (0,1%) e Nistatina (128μg/mL), e no teste do XTT, observou-se que α –terpinen (0,1%) e Nistatina (256μg/mL) diminuem a viabilidade quando comparado com o controle. Conclusão: Assim, pode-se afi rmar que α-terpineol pode ser uma alternativa para tratamento de infecções fúngicas
Porphyromonas endodontalis in chronic periodontitis: a clinical and microbiological cross-sectional study
Although previous studies have shown the presence of Porphyromonas endodontalis in chronic periodontitis associated with periapical lesions, the occurrence of this pathogen in diseased periodontal sites without periapical lesions has been poorly investigated.The aims of this study were to quantify P. endodontalis in patients with chronic periodontitis without periapical lesions, to evaluate the potential correlation of P. endodontalis with Porphyromonas gingivalis and Tannerella forsythia, and to evaluate the ability of periodontal treatment to reduce these pathogens.Patients with generalized chronic periodontitis were selected by recording clinical attachment level (CAL), probing depth (PD), and bleeding on probing (BOP). Subgingival samples from 30 diseased nonadjacent sites (CAL ≥ 5 mm, PD between 5 and 7 mm and positive BOP) and 30 healthy nonadjacent sites (PD ≤ 3 mm and negative BOP) were collected and subjected to microbial analysis by quantitative polymerase chain reaction (qPCR) The variables of age, PD, CAL and BOP of all individuals were analyzed using the paired t-test (GrapPad Prism5®). Data of bacteria quantification were subjected to a normality test (D'Agostino-Pearson Test). For bacterial correlation analysis, the Spearman correlation was used.Our results showed that diseased sites had significantly higher levels of P. endodontalis compared to healthy sites, similar to the results obtained for P. gingivalis and T. forsythia. The numbers of all bacterial species were reduced significantly after mechanical periodontal treatment. P. endodontalis was significantly correlated with the presence of T. forsythia and P. gingivalis in the diseased group.Our results suggest that there is a high prevalence of P. endodontalis, P. gingivalis and T. forsythia in periodontitis sites and that mechanical periodontal treatment is effective at reducing the pathogens studied
Biotipos de Streptococcus grupo mutans e avaliação de parametros clinicos e microbiologicos entre escolares de diferentes classes socio-economicas
Orientador: Jose Francisco HoflingTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Com o propósito de se analisar bioquimicamente e microbiologicamente a saliva de escolares de diferentes classes sócio econômicas, com idades de 6 a 8 anos da região de Piracicaba, 200 escolares totalizados pela soma de 40 crianças de 5 classes sócio econômicas (A à E), foram analisados procurando-se conhecer primeiramente a prevalência das espécies de Streptococcus grupo mutans e em segundo lugar, avaliar 'os parâmetros clínicos e microbiológicos, com ênfase em estudos sobre a atividade cariogênica dessas populações. Dados clínicos de cárie (ceos/CPOS) foram obtidos preliminarmente à coleta da
saliva. As amostras de saliva obtidas foram diluídas em solução salina, e posteriormente se meadas em meio de cultura S820. Previamente à diluição, a saliva concentrada foi analisada, medindo-se o fluxo salivar, índice de capacidade tampão e pH. Após o crescimento das colônias características, procedeu-se à contagem de UFC/ml de Streptococcus grupo mutans e Lactobacillus, ao lado da identificação e caracterização das espécies do grupo mutans mais prevalentes, através das provas de fermentação de carboidratos. Os resultados obtidos mostraram que das 491 amostras isoladas com características do grupo mutans, 78% desses microrganismos pertencem à espécie S. mutans , 12% à espécie S. sobrinus, e o restante dividindo-se em S. rattus, S. mutans V, S. cricetus e S. ferus em menores porcentagens, com predominância de S. mutans em todas as classes sócio econômicas. Nos indivíduos multicolonizados, a associação mais frequente foi de S. mutans / S. sobrinus (17%). Entre todas as classes sócio econômicas estudadas, uma parceJa s.ignificativa da amostra foi conside/iiada como pacientes de alto risco à cárie, visto que a contagem de S. mutans, LactobacilJus e o índice cariogênico foi considerado acima dos. índices normais relatados na literaturaj principalmente nas classes mais baixas (D/E). Dentre os diversos parâmetros analisados para se identificar: esses grupos de alto risco, como fluxo salivar, indicador de capacidade tampão,
contagem de S. mutans e LactobacilJus, índice ceos/CPOS, observa-se uma correlação estatisticamente significante para todas as classes sócio econômicas somente entre prevalência de cárie em dentes decíduos e dentes permanentes, sugestivo de que o índice ceos pode ser um indicativo de cáries futurasAbstract: Saliva samples from students aged 6 to 8 years were analysed in order to determine the prevalence of mutans streptococci serotypes and to correlate this microbiological para meter to dmfs/DMFS. Two hundred children were examined according to WHO criteria for dmfs/DMFS index, distributed in five socio-economic levels (A to E). Stimulated saliva samples were evaluated as to secretion rate, buffer capacity and pH; afier dilution the secretion was inoculated in~o the S820 culture media and the colony forming units per ml of saliva of mutans streptococci and Lactobacillus were determined. Representative colonies were isolated and classified by biochemical methods on the basis of carbohydrate fermentation. Seventy eight percent of the 491 samples tested were colonies of S. mutans, followed by S. sobrinus (11,61 %), S. rattus ( 4,69%), S. mutans V (2,65 %), S. cricetus (1,83%) and S. ferus (1,22%). The predominance of S. mutans was found in every socio-economic leveI. Among individuais harboring multiple species, the most frequent association detected was S. mutans / S. sobrinus (17%). A significative part of the population, particularly among the lower socio economic levei (D/E) was considered a high risk group in developing dental carie because of the high number of Streptococcus group mutans and Lactobacillus and high levels of dental caries index. The results also showed that among ali the parameters employed to identify such high risk populations, only dmfs showed statistical significance for every socio economic leveIDoutoradoBiologia e Patologia Buco-DentalDoutor em Ciência
Cyclosporin A-induced new cementum formation: a morphometric evaluation in the periapical region of rats
Cyclosporin A (CsA) is a potent immunosuppressor used in organ transplantation and in the management of various autoimmune diseases. Recent studies have shown that CsA stimulates deposition of cementum on root surfaces. The aim of this study was to evaluate the periapical cementum thickness and the apical foramen width in CsA-treated rats. Rats weighing 50 g were treated with a daily injection of 10 mg/kg body weight of CsA in the chow for 60 days. The cementum of the mandibular 1st molars was histologically and morphometricaly examined by analysis of 5-microm-thick serial buccolingual paraffin sections stained with hematoxylin and eosin. Histometric and stereologic analyses revealed the presence of large amounts of cementum in all root surfaces, particularly abundant in the periapical region and obliterating the foramen. The volume density of cementoblasts did not increase. Five to 90 days after the termination of CsA therapy, there was no reduction of cementum thickness. These results suggest that cementum deposition is not reversible after cessation of CsA treatment.Ciclosporina A (CsA) é um potente imunossupressor usado no transplante de órgãos e no tratamento de várias doenças autoimunes. Recentes estudos têm demonstrado que a CsA estimula a deposição de cemento na superfície radicular. O objetivo deste estudo foi de avaliar a espessura do cemento periapical e largura do forame apical em ratos tratados com CsA. Os ratos pesavam 50 g e foram tratados com doses diárias de 10 mg/kg de peso corporal de CsA no período de 60 dias. O cemento do primeiro molar inferior foi examinado histologicamente e morfometricamente por análises de cortes em parafina com 5µm de espessura no sentido vestíbulo-lingual e corados com hematoxilina e eosina. As análises histométricas e estereológicas revelaram a presença de largos depósitos de cemento em todas as superfícies radiculares, particularmente maior na região periapical e obliterando o forame. A densidade volumétrica dos cementoblastos não foi aumentada. No período de 5 a 90 dias após o término da terapia com CsA, não houve redução na espessura do cemento. Estes resultados sugerem que o depósito de cemento não é reversível após o tratamento com CsA ser cessado
Subinhibitory Concentrations of Triclosan Promote Streptococcus mutans Biofilm Formation and Adherence to Oral Epithelial Cells
Triclosan is a general membrane-active agent with a broad-spectrum antimicrobial activity that is commonly used in oral care products. In this study, we investigated the effect of sub-minimum inhibitory concentrations (MICs) of triclosan on the capacity of the cariogenic bacterium Streptococcus mutans to form biofilm and adhere to oral epithelial cells. As quantified by crystal violet staining, biofilm formation by two reference strains of S. mutans was dose-dependently promoted, in the range of 2.2- to 6.2-fold, by 1/2 and 1/4 MIC of triclosan. Observations by scanning electron microscopy revealed the presence of a dense biofilm attached to the polystyrene surface. Growth of S. mutans in the presence of triclosan at subMICs also increased its capacity to adhere to a monolayer of gingival epithelial cells. The expression of several genes involved in adherence and biofilm formation in S. mutans was investigated by quantitative RT-PCR. It was found that subMICs of triclosan significantly increased the expression of comD, gtfC, and luxS, and to a lesser extent of gtfB and atlA genes. These findings stress the importance of maintaining effective bactericidal concentrations of therapeutic triclosan since subMICs may promote colonization of the oral cavity by S. mutans
Presence of Candida spp. in infants oral cavity and its association with early childhood caries
spp., mainly C. albicans, colonizes oral cavity of infants. Transmission by mother to childbirth, pacifier use, feeding habits and caries are factors related to Candida oral colonization. Some researches related that early childhood caries favor the oral colonization of C. albicans. The present literature review described the presence of Candida spp. in oral cavity of infants and its association with early childhood caries (ECC). The literature was searched for original papers relating Candida, pacifier and baby bottle usage and ECC. The articles were selected using Bireme and Medline databases. Manual tracing of references cited in key papers was also elicited. It can be concluded that Candida spp. colonization in the infants oral cavity, especially C. albicans, can be related to the pacifier usage, feeding habits and caries lesions. The early childhood caries favor the C. albicans colonization, although its role in the carious process need further studies to be elucidate scientifically
Fibrinogen-Induced Streptococcus mutans Biofilm Formation and Adherence to Endothelial Cells
Streptococcus mutans, the predominant bacterial species associated with dental caries, can enter the bloodstream and cause infective endocarditis. The aim of this study was to investigate S. mutans biofilm formation and adherence to endothelial cells induced by human fibrinogen. The putative mechanism by which biofilm formation is induced as well as the impact of fibrinogen on S. mutans resistance to penicillin was also evaluated. Bovine plasma dose dependently induced biofilm formation by S. mutans. Of the various plasma proteins tested, only fibrinogen promoted the formation of biofilm in a dose-dependent manner. Scanning electron microscopy observations revealed the presence of complex aggregates of bacterial cells firmly attached to the polystyrene support. S. mutans in biofilms induced by the presence of fibrinogen was markedly resistant to the bactericidal effect of penicillin. Fibrinogen also significantly increased the adherence of S. mutans to endothelial cells. Neither S. mutans cells nor culture supernatants converted fibrinogen into fibrin. However, fibrinogen is specifically bound to the cell surface of S. mutans and may act as a bridging molecule to mediate biofilm formation. In conclusion, our study identified a new mechanism promoting S. mutans biofilm formation and adherence to endothelial cells which may contribute to infective endocarditis
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