ABSTRACT
Em Cabo Verde, arquipélago situado na Costa Ocidental Africana, os primeiros casos de dengue ocorreram em 2009, com a notificação de mais de 21.000 casos, a maioria desses registrados na Ilha de Santiago. O mosquito Aedes aegypti foi identificado como vetor, e ações para seu controle, usando os inseticidas temephos (larvicida) e a deltametrina (adulticida), têm sido implementadas. Objetiva-se com esse trabalho avaliar o atual status de suscetibilidade a inseticidas e caracterizar os mecanismos de resistência nessa população. Amostras de A. aegypti da ilha de Santiago foram coletadas através de armadilhas de oviposição, para o estabelecimento de uma população a ser analisada. Foram realizados bioensaios do tipo dose diagnóstica, usando garrafas impregnadas com doses únicas dos adulticidas malathion (organofosforado), deltametrina (piretróide) e cipermetrina (piretróide), e bioensaios do tipo dose resposta, usando múltiplas concentrações dos inseticidas temephos (organofosforado), Bacillus thuringiensis sorovariedade israelensis (bactéria entomopatogênica) e diflubenzuron (inibidor de síntese de quitina). Para a investigação dos mecanismos de resistências, foram realizados testes bioquímicos com substratos específicos para quantificar a atividade das enzimas glutationa S-transferases, esterases (alfa, beta e PNPA) e oxidases de função mista, ligadas a detoxificação de xenobióticos, e a taxa de inibição da acetilcolinesterase ligada a insensibilidade do sítio alvo...
Cape Verde, an archipelago located on the West African Coast, recorded the first cases of dengue in 2009 in an epidemic with more than 21,000 reportedcases. The worst affected area was Santiago Island...
Subject(s)
Animals , Aedes , Enzymes/toxicity , Insect Vectors/virology , Insecticide Resistance , Africa, Western , Bacillus thuringiensis/pathogenicity , Esterases/analysis , Glutathione Transferase/analysis , Malathion/toxicity , Toxicity Tests , Temefos/toxicityABSTRACT
A crude enzyme extract from a fungus, Gliomastix murorum, could be used in the synthesis of oligosaccharides that are essential to the food and drug industries. This extract may contaminate such products and lead to serious health problems. An investigation on the possible toxicity and mutagenic effect of the extract from this fungal isolate was carried out in Swiss Albino mice. One hundred and 50% of the crude enzyme extract were injected intraperitoneally into the mice every 2 days for 30 days. Normal saline (0.9%), cultivation medium, and cyclophosphamide (80 mg/kg body weight) were given to the control groups. The results indicated that the white blood cell count, serum creatinine, and uric acid of the treated mice were significantly higher than those of the controls (p<0.05), whereas the serum urea-N was lower. For the micronucleus test, mice treated with the extract, especially the group received 100% crude enzyme extract, showed a higher number of micronuclei in polychromatic erythrocytes, as compared to controls. Nevertheless, the micronucleus values were not as high as those found in mice treated with cyclophosphamide, the mutagenic agent. It can be concluded from the results that crude enzyme extract had minor toxic effects on various organ systems tested; more extensive investigation on the safe use of this extract is therefore necessary.