RESUMO
OBJECTIVES: The aim of the present study was to investigate an antimicrobial additive containing experimental resin composite with regards to its impact on biofilm formation under oral conditions. METHODS: Biofilms were established in situ on composite specimens (n=192) which contained octenidine dihydrochloride (ODH, 3 wt.% or 6 wt.%). Samples without antimicrobial additive served as control (n=96). Composite specimens were fixed on custom made splints and exposed to the oral cavity of six healthy volunteers for three or seven days. Biofilm formation was assessed by scanning electron microscopy (SEM) and fluorescence microscopy (FM). RESULTS: The biofilm formation was significantly reduced on ODH containing samples compared to controls after three as well as after seven days in situ. FM evaluation additionally showed a lower viability of the reduced biofilms for both ODH concentrations. SIGNIFICANCE: During this short term investigation, incorporation of ODH into resin based composite materials caused biofilm inhibiting effects in situ.
Assuntos
Resinas Acrílicas/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Resinas Compostas/farmacologia , Boca/microbiologia , Poliuretanos/farmacologia , Piridinas/farmacologia , Resinas Acrílicas/química , Adulto , Resinas Compostas/química , Feminino , Humanos , Iminas , Masculino , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Estrutura Molecular , Poliuretanos/química , Piridinas/química , Análise de Regressão , Estatísticas não ParamétricasRESUMO
An increasingly exploited strategy for the isolation of stem cells is based on the increased efflux of Hoechst 33342 lipophilic dye mediated by ABCG2, an ATP-binding cassette transporter which is highly expressed in various stem cells. We found ABCG2 expression to be present at later stages of spermatogenesis. Western blot analysis using an anti-ABCG2 antibody revealed expression of a 72kDa band in mature sperm obtained from mice, rats, bulls or humans. Immunocytochemistry studies revealed acrosomal staining pattern of ABCG2 in spermatozoa. Experiments using the Hoechst 33342 ABCG2 substrate and the ABCG2-specific inhibitor FTC demonstrated efflux activity of ABCG2 in mature sperm. Incubation of sperm in capacitating medium in the presence of the ABCG2-inhibitor FTC resulted in decreased cholesterol depletion compared to sperm incubated in the absence of FTC. Our results demonstrate that ABCG2 is expressed at the acrosome in mature sperm. ABCG2 may thus serve to mediate cholesterol removal.
