Further phenotypic characterization of pso mutants of Saccharomyces cerevisiae with respect to DNA repair and response to oxidative stress

The sensitivity responses of seven pso mutants of Saccharomyces cerevisiae towards the mutagens N-nitrosodiethylamine (NDEA), 1,2:7,8-diepoxyoctane (DEO), and 8-hydroxyquinoline (8HQ) further substantiated their allocation into two distinct groups: genes PSO1 (allelic to REV3), PSO2 (SNM1), PSO4 (PRP19), and PSO5 (RAD16) constitute one group in that they are involved in repair of damaged DNA or in RNA processing whereas genes PSO6 (ERG3) and PSO7 (COX11) are related to metabolic steps protecting from oxidative stress and thus form a second group, not responsible for DNA repair. PSO3 has not yet been molecularly characterized but its pleiotropic phenotype would allow its integration into either group. The first three PSO genes of the DNA repair group and PSO3, apart from being sensitive to photo-activated psoralens, have another common phenotype: they are also involved in error-prone DNA repair. While all mutants of the DNA repair group and pso3 were sensitive to DEO and NDEA the pso6 mutant revealed WT or near WT resistance to these mutagens. As expected, the repair-proficient pso7-1 and cox11-Delta mutant alleles conferred high sensitivity to NDEA, a chemical known to be metabolized via redox cycling that yields hydroxylamine radicals and reactive oxygen species. All pso mutants exhibited some sensitivity to 8HQ and again pso7-1 and cox11-Delta conferred the highest sensitivity to this drug. Double mutant snm1-Delta cox11-Delta exhibited additivity of 8HQ and NDEA sensitivities of the single mutants, indicating that two different repair/recovery systems are involved in survival. DEO sensitivity of the double mutant was equal or less than that of the single snm1-Delta mutant. In order to determine if there was oxidative damage to nucleotide bases by these drugs we employed an established bacterial test with and without metabolic activation. After S9-mix biotransformation, NDEA and to a lesser extent 8HQ, lead to significantly higher mutagenesis in an Escherichia coli tester strain WP2-IC203 as compared to WP2, whereas DEO-induced mutagenicity remained unchanged

Tomografia por emissäo de fóton único em epilepsia temporal: estudos intercríticos e críticos com análise visual e semi quantitativa / Single photon emission tomography in temporal epilepsy: interictal and ictal studies with visual and semi quantitative analysis

Vinte e oito estudos intercríticos e 9 críticos/pós críticos de tomografia por emissäo de fóton único (SPECT) foram realizados em 27 pacientes com epilepsia do lobo temporal e esclerose mesial temporal. Estudos intercríticos localizaram corretamente a área epileptogênica em 19 (67 por cento) dos pacientes pela análise visual e 16 (61,5 por cento) pela semi quantitativa, com 10,7 e 15,3 por cento, de falsa lateralizaçä respectivamente. Todos os 9 estudos críticos/ pós críticos detectaram o hemosfério epileptogênico e permitiram localizaçäo correta da área epileptogênica em 5 de 9 pacientes cujos exames intercríticos haviam sido inonclusivos. Três estudos realizados durante crises secundariamente generalizadas e simétricas mostraram hiperfluxo restrito ao lobo temporal

Derivados azoicos da oxina com sulfas potencialmente antimalaricas / Oxine azoic derivatives with potentially antimalarial sulfonamides

Com o objetivo de obter farmacos potencialmente antimalaricos prepararam-se, pelo processo de hibridacao molecular, cinco compostos mediante reacao do sal de diazonio e sulfas antimalaricas - sulfadiazina, sulfadoxina, sulfametoxipiridazina, sulfametoxazol e sulfamonometoxina - com a oxina (8-hidroxiquinolina). Submetidos a analises espectrometricas - IV, UV, RMP -, os derivados apresentaram caracteristicas das estruturas propostas

Efeito espermicida da associaçäo ácido bórico/sulfato de 8-hidroxiquinolina em pessários de manteiga de cacau (Parte II) / Spermicidal effect of the association boric acid/8-hydroxichinolin sulfate in vaginal suppository of cacao butter (Part II)

Os autores demonstram, usando a prova de Sims-Huhner, que o uso da associaçäo ácido bórico/quinosol em pessários de manteiga de cacau apresenta marcante efeito espermicida em todas as pacientes estudadas

Efeito espermicida in vitro da associaçäo ácido bórico-sulfato de 8-hidroxiquinolina em pessários de manteiga de cacau / In vitro spermicidal effect of the combination of acid 8-hydroxyquinoline sulfate in vaginal suppository of cacao's butter

O autor demonstra, com técnica própria in vitro, que a associaçäo ácido bórico-quinosol apresenta marcante feito espermicida em 100% da populaçäo de espermatozóides em 10 lotes de sêmen humano testados