Drug susceptibility of Brazilian strains of Mycobacterium bovis using traditional and molecular techniques

Transmission of Mycobacterium bovis from cattle to humans has been reported and can cause tuberculosis (Tb) and a problem in certain risk populations. Therefore, knowledge of resistance of M. bovis towards antibiotics used for therapy of human Tb could help avoiding cure delay and treatment cost increase when dealing with drug resistant organisms. We therefore evaluated the susceptibility of M. bovis isolates towards streptomycin, isoniazide, rifampicin, ethambutol, and ethionamide, the first line antibiotics for human Tb. Therefore, 185 clinical samples from cattle with clinical signs of tuberculosis were processed and submitted to culturing and bacterial isolates to identification and drug susceptibility testing using the proportion method. Among 89 mycobacterial strains, 65 were identified as M. bovis and none were resistant to any of the antibiotics used. Confirmation of present results by future studies, enrolling a large number of isolates and designed to properly represent Brazilian regions, may favor the idea of using isoniazide preventive therapy as part of a Tb control strategy in special situations. Also, nucleic acids from bacterial isolates were submitted to rifoligotyping, a recently described reverse hybridization assay for detection of mutations causing resistance towards rifampicin. Concordance between the conventional and the molecular test was 100 percent, demonstrating the use of such methodology for rapid evaluation of drug susceptibility in M. bovis.

Estudo da profundidade de polimerizaçäo de resina por alguns aparelhos fotopolimerizadores: relaçäo com a dureza / Study of the resin cure depth by some light cure units related to hardness

Este trabalho visa avaliar a profundidade de polimerizaçäo de 05 (cinco) aparelhos fotopolimerizadores em uso da Faculdade de Odontologia da UERJ. Os aparelhos fotopolimerizadores foram avaliados por meio de um medidor de intensidade de luz, o radiômetro (Demetron Curing Tadiometer). Este registrou a integridade luminosa emitida por cada aparelho durante 40 segundos. Uma correlaçäo entre intensidade de luz obtida pelo radiômetro e profundidade de polimerizaçäo foi alcançada