RESUMEN
This study evaluated the potential antimicrobial properties of a polyguanidine (CatDex) on two oral bacteria. Chlorhexidine gluconate 1340 µmoL L-1 (CHX 0.12%) was used as control. Streptococcus mutans (S. mutans) and Porphyromonas gingivalis (P. gingivalis) were grown in BHI media. Bacterial sensitivity and antimicrobial activity were determined by the minimum inhibitory concentration (MIC) and Kirby-Bauer methods. To study side effects, that is, toxicity, dental pulp stem cells (DPSCs) were used. Fluorometric cytotoxicity and confocal microscopy assays were used in order to test cell viability. CatDex inhibited growth of S. mutans at all concentrations and growth of P. gingivalis at all concentrations except 25 µmoL L-1. The MIC of CatDex was 50 µmoL L-1 for both S. mutans and P. gingivalis. The inhibition of bacteria exposed for 8 h at 50 µmoL L-1 of CatDex exhibited increased antimicrobial activity over time, with 91% inhibition in both bacteria. The antimicrobial activities of CatDex and CHX were similar when tested on two common bacteria. CatDex was significantly less toxic to DPSCs. CatDex toxicity depended on time and not on concentration. With regard to clinical relevance, CatDex may have potential as a novel antimicrobial agent. Further studies are in progress.
RESUMEN
Se administró la HEPB por vía oral a ratones (15 machos y 15 hembras) a dosis de 0, 100, 150, 230 y 350 mg/kg peso durante 13 semanas. Cincuenta por ciento de los animales tratados con la dosis más alta (350 mg/kg) murieron. Sin embargo, a las dosis inferiores no se observaron efectos sobre el peso corporal, valores hematológicos, química sanguínea, composición de la orina y peso de los órganos. Se concluye que la administración subcrónica de la HEPB hasta dosis de 230 mg/kg, no produce efectos tóxicos en esta especie. Esta dosis representa una cantidad considerable en relación a la probable dosis a utilizarse en humanos