Antifungal and post-antifungal effects of chlorhexidine, fluconazole, chitosanand its combinations on Candida albicans

Objective: The aim of this work was to assess the antifungal and post-antifungal effects of chlorhexidine, fluconazole,chitosan and its combinations on virulence factors of Candida albicans. Study Design: Ten isolated strains of Candida albicans obtained from 10 patients with oral candidiasis and acollection strain of C. albicans were treated with antifungal agents in different concentrations or combinationsof them. Virulence factors analyzed were the cell surface hydrophobicity, the germinative tube development, the phospholipase activity and the post-antifungal effect of that exposure. Results: Virulence factors of the isolated strains obtained from patients together with the collection strain showed significant decreases with the different antifungal treatments, except for hydrophobicity and phospholipase activity.The development of germinative tube was the most sensitive factor to all the antifungal agents used. Untreated strains as well as the ones treated with antifungal agents showed a positive correlation among the virulence factorsanalyzed. No synergic effects arose from the combinations of the used drugs. Conclusions: C. albicans isolated strains from patients showed high phospholipase activity and germinative tubeproduction, which corroborates their capacity to infect the oral mucosa and the high prevalence of species. Asa whole, our results imply that short exposures to sub-inhibitory concentrations of the antifungal agents underanalysis, isolated or combined, can modulate the way virulence factors get manifested, thus decreasing their pathogenicity (AU)

Antifungal and post-antifungal effects of chlorhexidine, fluconazole, chitosan and its combinations on Candida albicans.

OBJECTIVE: The aim of this work was to assess the antifungal and post-antifungal effects of chlorhexidine, fluconazole, chitosan and its combinations on virulence factors of Candida albicans. STUDY DESIGN: Ten isolated strains of Candida albicans obtained from 10 patients with oral candidiasis and a collection strain of C. albicans were treated with antifungal agents in different concentrations or combinations of them. Virulence factors analyzed were the cell surface hydrophobicity, the germinative tube development, the phospholipase activity and the post-antifungal effect of that exposure. RESULTS: Virulence factors of the isolated strains obtained from patients together with the collection strain showed significant decreases with the different antifungal treatments, except for hydrophobicity and phospholipase activity. The development of germinative tube was the most sensitive factor to all the antifungal agents used. Untreated strains as well as the ones treated with antifungal agents showed a positive correlation among the virulence factors analyzed. No synergic effects arose from the combinations of the used drugs. CONCLUSIONS: C. albicans isolated strains from patients showed high phospholipase activity and germinative tube production, which corroborates their capacity to infect the oral mucosa and the high prevalence of species. As a whole, our results imply that short exposures to sub-inhibitory concentrations of the antifungal agents under analysis, isolated or combined, can modulate the way virulence factors get manifested, thus decreasing their pathogenicity.

Efecto del quitosán de alto peso molecular y del alginato de sodio sobre la hidrofobicidad y adhesión de Candida albicans a células / Effect of the high molecular weight chitosan and sodium alginate on Candida albicans hydrophobicity and adhesion to cells

Objetivo: Evaluar el efecto del quitosán de alto peso molecular (QAPM) y del alginato de sodio (NaAL) sobre la hidrofobicidad superficial de Candida albicans y la adhesión de esta levadura a células epiteliales y fibroblastos de distinto origen. Diseño del estudio: Para el estudio de la hidrofobicidad, las levaduras (n=7) se hicieron crecer en agar glucosado de Sabouraud suplementado con QAPM o NaAL o en ausencia de los mismos (controles). La determinación de la hidrofobicidadse realizó por el método de adhesión a hidrocarburos utilizando dos solventes orgánicos (xileno y cloroformo). En los estudios de adhesión, las levaduras se pusieron en contacto con soluciones de biopolímeros y luego se enfrentaron a diferentes células (fibroblastos humanos y de rata y células epiteliales Hep-2). La cuantificación se realizó por microscopía óptica.Resultados: Se observó una disminución del 44% de la hidrofobicidad en presencia de QAPM y del 82%, con NaAL, o del 30% con QAPM y 19% con NaAL, cuando los solventes orgánicos empleados fueron cloroformo o xileno, respectivamente. La adhesión de C. albicans a células epiteliales y fibroblastos humanos disminuyó significativamente con ambos biopolímeros. En el caso de los fibroblastos de encía de rata, sólo se observó una disminución con NaAL. En ninguno de los experimentos se observaron diferencias significativas en asociación al tipo de fibroblasto empleado. Conclusiones: Los biopolímeros resultaron efectivos en la reducción de la hidrofobicidad y la adhesión de C. albicans a células, las cuales son importantes factores de virulencia relacionados con la colonización de los tejidos blandos del hospedador o superficies acrílicas presentes en el sistema estomatognático

The aim of the present paper is to evaluate the effect of the high molecular weight chitosan (HMWC) and of sodium alginate (NaAL) on surface hydrophobicity of Candida albicans and on adhesion of the yeast to epithelial cells and fibroblasts of different proceeding.For this study, a collection strain and seven isolates of C. albicans from saliva (patients with denture stomatitis) were grown in Sabouraud glucose agar supplemented with HMWC or NaAL or in absence of them (control). Hydrophobicity was determined by adhesion to hydrocarbons method using two organic media (xylene and chloroform). For adhesion experiments, aqueous suspensions of yeasts were contacted with solutions of biopolymers and different cells (rat and human fibroblasts and epithelial cells Hep-2). The quantification of adhesion was made by optical microscopy.Results: a decrease in hydrophobicity was observed in the presence of HMWC (44%) and of NaAL (82%) when chloroformwas employed as organic medium, meanwhile the decreases were of 30% with HMWC and 19% with NaAL in the presence of xylene. Adhesion of C. albicans to epithelial cells and human fibroblasts decreased significantly with both biopolymers. In the case of rat fibroblasts, a decrease was observed only with NaAL. None of experiments showed significant differences associated to fibroblast type.Conclusions: biopolymers showed effectiveness in reducing hydrophobicity and adhesion of C. albicans to cells, which are important virulence factors related to colonization of the soft tissues of host or acrylic surfaces present in the oral system

Effect of the high molecular weight chitosan and sodium alginate on Candida albicans hydrophobicity and adhesion to cells.

UNLABELLED: The aim of the present paper is to evaluate the effect of the high molecular weight chitosan (HMWC) and of sodium alginate (NaAL) on surface hydrophobicity of Candida albicans and on adhesion of the yeast to epithelial cells and fibroblasts of different proceeding. For this study, a collection strain and seven isolates of C. albicans from saliva (patients with denture stomatitis) were grown in Sabouraud glucose agar supplemented with HMWC or NaAL or in absence of them (control). Hydrophobicity was determined by adhesion to hydrocarbons method using two organic media (xylene and chloroform). For adhesion experiments, aqueous suspensions of yeasts were contacted with solutions of biopolymers and different cells (rat and human fibroblasts and epithelial cells Hep-2). The quantification of adhesion was made by optical microscopy. RESULTS: A decrease in hydrophobicity was observed in the presence of HMWC (44%) and of NaAL (82%) when chloroform was employed as organic medium, meanwhile the decreases were of 30% with HMWC and 19% with NaAL in the presence of xylene. Adhesion of C. albicans to epithelial cells and human fibroblasts decreased significantly with both biopolymers. In the case of rat fibroblasts, a decrease was observed only with NaAL. None of experiments showed significant differences associated to fibroblast type. CONCLUSIONS: Biopolymers showed effectiveness in reducing hydrophobicity and adhesion of C. albicans to cells, which are important virulence factors related to colonization of the soft tissues of host or acrylic surfaces present in the oral system.

Evaluación del estado de salud bucodental en preescolares: estudio epidemiológico longitudinal (1993-1994), Córdoba, Argentina / Oral health condition evaluation of kindergarten children: longitudinal epidemiologic study (1993-1994), Córdoba, Argentina

Se realizó un estudio longitudinal de un año de duración en una muestra (n=820) de la población preescolar de 4 años de la Ciudad de Córdoba, Argentina, para estabelecer la participación de diversas variables en la incidencia de caries. Los índices ceo-d, ceo-s, de higiene oral y de salud bucodental, como también las tasas de incidencia y los riesgos relativos de caries estuvieron inversamente relacionados con el Nivel Económicosocial (NES) de los niños. En los preescolares del NES III (proletariado típico, proletariado no típico y subproletariado), el riesgo relativo de experimentar caries fue casi cinco veces mayor (RR=4,9) que en el NES I (burguesías empresarial y gerencial). En el NES I, la mayoría de las nuevas lesiones se localizaron en las superficies lisas (61,2 por ciento), mientras que en el NES III afectaron predominantemente las superficies oclusales de los melares (66,3 por ciento). El consumo diario de azúcares fue mayor en los niños del NES III, pero la experiencia de caries se correlacionó débilmente con la cantidad o frecuencia de ingesta de estos carbohidratos (r=0,40 y 0,52, respectivamente). No se registraron diferencias significativas interniveles en los parámetros bioquímicos salivales analizados. El cepillado dental asistido y las aplicaciones tópicas fluoruradas disminuyeron fuertemente la incidencia de caries en los niños del NES III, reducienco las correspondientes tasas a valores muy próximos a los del NES I (0,31, 0,23 y 0,22 vs. 0,21). Se concluye que los niños del NES III, por su susceptibilidad a la caries, deberían ser asistidos precozmente con medidas preventivas eficaces, como lo son el cepillado dental asistido y las aplicaciones tópicas fluoruradas

Estado de salud bucodental de escolares residentes en localidades abastecidas con agua de consumo humano de muy alto y muy bajo contenido de fluoruros / State of oral health among schoolchildren living in towns supplied with drinking water containing very high and very low levels of fluoride

Descreve e analisa os resultados de uma pesquisa epidemiológica de corte transversal destinada a avaliar o estado de saúde buco-dental de escolares de 6-7 e 12-13 anos, residentes em Sampacho e Porteña, duas localidades da Província de Córdoba (Argentina), abastecidas com água potável contendo quantidade de F- muito diferentes. Em Sampacho, o nível de F- é de 9,05 mg/l enquanto que em Porteña a concentraçäo é de 0,19 mg/l. A proporçäo de escolares (6-7 e 12-13 anos) que näo apresentaram cárie foi significativamente maior em Sampacho do que em Porteña, enquanto, que os índices ceo-d, ceo-s, CPO-D e CPO-S resultaram consideravelmente mais altos nesta última localidade. A severidade da doença de cárie nas crianças de 12-13 anos de Sampacho esteve compreendida entre as categorias baixa e moderada (CPO-D = 2,53), enquanto que em suas similares em Porteña atingiu o grau de moderada e alta (CPO-D=4,41). Näo se registrou nenhum caso de fluorose dental em Porteña enquanto que em Sampacho houve uma alta proporçäo de crianças que apresentou fluoroses leve (6-7 anos) e leve ou intensa (12-13 anos). Os níveis salivares de cálcio, fosfatos, tiocianato, proteínas totais e lg A secretora foram muito similares nos escolares de ambas localidades, e também entre crianças com diferentes tipos de cárie e diferentes graus de gravidade de fluorose. Conclui ser necessária a aplicaçäo de medidas sanitárias urgentes (preventivas ou curativas) para reduzir ou controlar as doenças de cárie em Porteña e a fluorose dental em Sampacho

Condición socioeconómica, salud bucodental y factores asociados en la población infantil (5 años) de la ciudad de Córdoba, Argentina / Socio-economic status, oral health and related factors in a child population (5 years old) of the Cordoba city, Argentina

Se exponen e interpretan los resultados de una investigación referida al estado de salud bucodental de preescolares (5 años) de la ciudad de Córdoba (Argentina). El 95,8 por ciento de los niños del nivel económico social más alto (NES I) tenía un ceo-d menor o igual que el percentilo 80 de la población infantil, mientras que en la categoría socioeconómica más baja (NES III) sólo el 66,9 por ciento de los niños no excedía ese valor. Las superficies oclusales de los molares fueron las que presentaban mayor experiencia de caries, aunque la enfermedad se inició preferentemente en el segundo molar superior (NES I) y en el segundo molar inferior (NES III). El consumo de golosinas incrementó la frecuencia de caries en los niños de los NES I y II, no así en los del NES III. La práctica del cepillado y del control odontológico tuvieron muy poco efecto sobre la salud bucodental. Las concentraciones salivales de calcio, fosfatos, proteínas totales, glucoproteínas e IgA secretoria resultaron casi idénticas en todos los niveles socioeconómicos y no estuvieron relacionadas con la experiencia de caries