Evaluation and comparison of cytotoxicity and bioactivity of chemomechanical caries removal agents on stem cells from human exfoliated deciduous teeth.

AIM: To investigate and compare the cytotoxicity and bioactivity of CMCR agents on stem cells derived from exfoliated deciduous teeth. METHODOLOGY: MTT assay, flow cytometry, Alizarin Red staining and scratch assay were used to assess the cellular viability, apoptosis, calcium matrix deposits and cell migration, respectively. The gene expression of ALP and BMP-2 was measured with RT-PCR. One-way ANOVA and Bonferroni post-test was used for statistical analysis. RESULTS: 0.5% Carisolv showed highest cell proliferation and calcium matrix formation, whereas 0.5% Papacarie reported the highest% live cells and cell migration. The highest mRNA expression of ALP and BMP-2 was reported in SHEDs cultured in 0.5% Papacarie (after 72 h incubation) and 0.5% Carisolv (after 24 h incubation), respectively. CONCLUSION: CMCR agents are biocompatible and bioactive when cultured in stem cells derived from exfoliated primary teeth.

Determination of MICs of levofloxacin for Mycobacterium tuberculosis with gyrA mutations.

The purpose of the present study was to correlate gyrA mutations found in Mycobacterium tuberculosis isolates using the GenoType(®) MTBDRsl assay with minimum inhibitory concentrations of the fluoroquinolone levofloxacin (LVX). Of 123 archived clinical M. tuberculosis isolates evaluated, 93 isolates had an Ala90Val, Ser91Pro, Asp94Ala, Asn/Tyr, Gly or His mutation and 30 were wild-type. Phenotypically, gyrA mutations Ala90Val, Ser91Pro or Asp94Ala showed a low level of resistance to LVX, while Asp94Asn/Tyr, Asp94Gly or Asp94His mutations had high-level resistance.