Citotoxicity evaluation of three dental adhesives on vero cells in vitro.

BACKGROUND: To evaluate, in vitro, the potential cytotoxicity of three different dental adhesives systems (Adper Single Bond 2 -SB, Silorane System Adhesive Bond -SSAB and Single Bond Universal -SBU) on cultivated Vero cells after different contact times. MATERIAL AND METHODS: The cells were cultured in a concentration of 2 x 105 cells/mL for 24h and grown to sub-confluent monolayers. VERO cells were exposed to 25µl of conditioned extracts obtained from 24h, 48h and 72h immersion of adhesive samples in culture medium (DMEM), immediately after polymerization. Fresh DMEM was used as negative control. Cell metabolism was evaluated by the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2, 5diphenyl-tetrazolium bromide). The data were analyzed statistically by ANOVA, considering a significance of 5%. RESULTS: The values of cell viability ranged from 94.2% at 72h (SBU) to 109.6% at 48h (SB). The mean percentage of viability after exposure to the extracts of SB, SSAB and SBU were 103.2%, 100.63% and 97.43%, respectively. There was no statistically significant difference (p= 0.342) between the experimental and negative control groups. CONCLUSIONS: At all exposure times, all adhesives tested in this study presented no cytotoxicity to Vero cells in vitro. Key words:Biocompatibility, cytotoxicity, dental adhesives, Vero cells.

Study of the activity of 3-benzyl-5-(4-chloro-arylazo)-4-thioxo-imidazolidin-2-one against Schistosomiasis mansoni in mice.

Previous studies conducted with the imidazolidinic derivative 3-benzyl-5-(4-chloro-arylazo)-4-thioxo-imidazolidin-2-one (LPSF-PT05) show outstanding activity against adult Schistosoma mansoni worms in vitro. In the first phase of this study, S. mansoni-infected mice were treated, orally, with 100 mg/Kg of the LPSF-PT05 in three formulations: Tween 80 and saline solution, oil/water (70 : 30) emulsion, and solid dispersion with polyethylene glycol (PEG). In the second phase, three other doses of the LPSF-PT05 in PEG were tested: 3, 10, 30 mg/kg. These treatment regimens significantly reduced the number of recovered worms due to increases in the solubility of the compound in this formulation; the greatest reduction (70.5%) was observed at the dose of 100 mg/kg. There was no changes in the pattern of mature egg compared to immature eggs; however there was a significant increase in the number of dead eggs. Histopathological analysis of liver tissue showed changes in morphological aspects of the hepatic parenchyma with decrease exudative-productive hepatic granuloma stages, although we found no significant differences in IFN-γ, IL-4, IL-10, or NO production in response to the specific antigen SEA. The results show the derivative LPSF-PT05 to be a potential candidate in the etiological treatment of schistosomiasis with a possible dampening effect of the granulomatous process.

Embryotoxicity in vitro with extract of Indigofera suffruticosa leaves.

Aqueous extract of leaves of Indigofera suffruticosa (AELIs) were studied for adverse effects in preimplantation mouse embryos. Two-cell mouse embryos were cultured for 94 h in human tubal fluid medium (HTF), and AELIs at a concentration of 5 or 10 mg/ml. On Day 4 of culture, morulae and blastocysts were collected for morphological analysis of blastomeres. We found that embryos exposed to the higher concentration of AELIs (10 mg/ml) did not develop and all embryos persisted at the two-cell stage. Those embryos exposed to the lower concentration (5 mg/ml) showed development until morula, blastocyst and hatched blastocyst stages that were similar to the controls. These results suggest that use of AELIs may be hazardous to humans who make use of it in folk medicine.