Influence of CYP1A1, CYP2E1, GSTM3 and NAT2 genetic polymorphisms in oral cancer susceptibility: Results from a case-control study in Rio de Janeiro

Xenobiotic metabolizing enzymes are involved in the detoxification of many carcinogens and may be important in modulating cancer susceptibility. CYP1A1, CYP2E1, GSTM3, and NAT2 polymorphisms were determined in peripheral blood DNA of 231 oral cancer patients and 212 hospital controls in Rio de Janeiro, Brazil, using the PCR-RFLP technique. NAT2 polymorphism distribution was different between cases and controls (P = 0.035), with an overrepresentation of NAT2*11 mutant allele in controls. Risk analysis showed that NAT2 4/4 individuals (OR = 1.95, 95% CI = 1.05-3.60) and combined GSTM3 and NAT2 heterozygotes (OR = 1.94, 95% CI = 1.04-3.66) were at increased oral cancer risk. No statistically significant association was observed for CYP1A1 and CYP2E1 polymorphisms. Our results suggest that NAT2 polymorphism, alone or combined with GSTM3, may modulate susceptibility to oral cancer in Rio de Janeiro. © 2005 Elsevier Ltd. All rights reserved

Glutathione S-transferase polymorphisms and oral cancer: A case-control study in Rio de Janeiro, Brazil

This study evaluates the influence of genetic polymorphisms at GSTM1, GSTT1 and GSTP1 gene loci on oral cancer susceptibility among Brazilians from Rio de Janeiro. DNA extracted from white blood cells of 231 oral cancer patients and 212 hospital controls was analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods. GSTM1 polymorphism distribution was different between cases and controls (P = 0.006), with an overrepresentation of GSTM1 A/B genotype in controls. GSTM1 A/B individuals were at decreased oral cancer risk (OR = 0.08; 95% CI = 0.05-0.62). No statistically significant association was observed for GSTT1 and GSTP1 polymorphisms. Differences in the GSTM1 and GSTT1 null genotype frequencies were observed between individuals of European origin and African origin, but these genotypes do not seem to influence the risk of oral cancer. Therefore, these results do not support the hypothesis of increased risk of GSTP1 G/G, GSTM1 or GSTT1 null genotypes for developing cancer in oral cavity, but the GSTM1 A/B genotype emerged as a protective factor. \ua9 2007 Elsevier Ltd. All rights reserved

Severe scorpion envenomation in Brazil: clinical, laboratory and anatomopathological aspects Escorpionismo grave no Brasil: aspectos clínicos, laboratoriais e anatomopatológicos

Scorpion stings in Brazil are important not only because of their incidence but also for their potential ability to induce severe, and often fatal, clinical situations, especially among children. In this report we present the clinical and laboratory data of 4 patients victims of scorpion stings by T. serrulatus, who developed heart failure and pulmonary edema, with 3 of them dying within 24 hours of the sting. Anatomopathologic study of these patients revealed diffuse areas of myocardiocytolysis in addition to pulmonary edema. The surviving child presented enzymatic, electrocardiographic and echocardiographic changes compatible with severe cardiac involvement, which were reversed within 5 days. These findings reinforce the need for continuous monitoring of patients with severe scorpion envenoming during the hours immediately following the sting.<br>Os acidentes escorpiônicos no Brasil, assumem grande importancia não só pela sua incidência como pela sua potencialidade em induzir quadros clínicos graves, muitas vezes fatais, principalmente em crianças. Apresentamos neste relato os dados clínicos e laboratoriais de 4 pacientes vítimas de escorpionismo, causado pelo T. serrulatus, que evoluíram com falência cardíaca e edema pulmonar, sendo que 3 foram a óbito dentro das primeiras 24 horas após acidente. O estudo anátomopatológico desses pacientes revelou áreas de miocardiocitólise, além do edema pulmonar. Na criança que sobreviveu foram detectadas alterações enzimáticas, eletro e ecocardiográficas compatíveis com grave comprometimento cardíaco, reversíveis dentro de 5 dias. Tais achados reafirmam a necessidade de monitorização contínua no paciente com escorpionismo grave, nas horas subsequentes ao envenenamento

Susceptibility of Aedes aegypti larvae to temephos and Bacillus thuringiensis var israelensis in integrated control Susceptibilidade de larvas de Aedes aegypti ao tratamento integrado com temephos e Bacillus thuringiensis var israelensis

The susceptibility of field collected Aedes aegypti larvae was evaluated in terms of median lethal time (LT50) and final mortality, when treated with temephos, Bacillus thuringiensis var israelensis as well as mixtures of these two agents. Third instar larvae were shown to be more susceptible than early and late fourth instar ones to the entomopathogen. Survival of some individuals when exposed to temephos suggest possible resistance. Temporal synergism in early fourth instar larvae was detected when they were exposed to mixtures of Bti-temephos. The possibility of this integrated treatment is commented on.<br>A susceptibilidade de larvas de Aedes aegypti coletadas no campo foi avaliada em termos do tempo letal mediano (TL50) e da mortalidade final, quando tratadas com temephos, Bacillus thuringiensis var israelensis ou misturas desses dois agentes. As larvas de terceiro estádio mostraram-se mais suceptíveis ao patógeno do que aquelas no início ou no fim do quarto estádio. A sobrevivência de alguns indivíduos aos tratamentos com temephos permite sugerir a possibilidade de resistência. Foi detectada a existência de sinergismo temporal, quando larvas no início do quarto estádio foram tratadas com as misturas do Bti com o temephos. A possibilidade do tratamento integrado é comentada

Perfil bioquímico sorológico de bovinos inoculados experimentalmente com veneno crotálico iodado livre e iodado incorporado em liposomas Serological biochemical profile of bovines poisoned experimentally with free iodized crotalic poison and iodized incorporated in lipossomes

Investigou-se o perfil sorológico de bovinos inoculados com veneno crotálico detoxificado pelo método de iodação e iodação com encapsulação em liposomas. Onze fêmeas com idade média de 18 meses e peso médio de160kg, foram inoculadas com 0,03mg/kg de peso vivo do veneno crotálico do tipo crotamina positivo. Cinco animais receberam o veneno iodado livre, cinco o iodado encapsulado em liposomas e um animal recebeu o mesmo veneno na forma natural, para controle da letalidade da amostra de veneno utilizada. Não houve alterações significativas na concentração de proteínas totais, uréia e creatinina em ambos os tratamentos. Foi observada diferença significativa na concentração de creatinafosfoquinase a partir de duas horas após a inoculação do veneno. A iodação do veneno crotálico, com ou sem incorporação em liposomas, suprimiu seus efeitos deletérios sobre o perfil bioquímico de bovinos.<br>It was studied the activity of the Crotalus venom detoxified encapsulated in lipossomes or non-encapsulated by the method of controlled iodination on the biochemical profile of bovines. Eleven 18-months-old female bovines, weighting 160kg in average were used in this study. Groups of five animals were inoculated intramuscularly with a dose of 0,03mg/kg with either the detoxified non-encapsulated venom or the detoxified encapsulated venom. One control animal received the same dose of non detoxified venom by the same route. No significant differences were observed between the study groups for the parameters of total protein, urea and creatinine. Differences were observed for creatine phosfokinase at times T O and T12 for the group treated with the iodinated venom encapsulated in liposomes. The detoxification process abolished the activity of the venom in the encapsulated or nonencapsulated form on the biochemical parameters and renal activity of bovine