RESUMO
The sterile insect technique (SIT) is a promising pest control method in terms of efficacy and environmental compatibility. In this study, we determined the efficacy of thiotepa-sterilised males in reducing the target Aedes aegypti populations. Treated male pupae were released weekly into large laboratory cages at a constant ratio of either 5:1 or 2:1 sterile-to-fertile males. A two-to-one release ratio reduced the hatch rate of eggs laid in the cage by approximately a third and reduced the adult catch rate by approximately a quarter, but a 5:1 release drove the population to elimination after 15 weeks of release. These results indicate that thiotepa exposure is an effective means of sterilising Ae. aegypti and males thus treated are able to reduce the reproductive capacity of a stable population under laboratory conditions. Further testing of the method in semi-field enclosures is required to evaluate the mating competitiveness of sterile males when exposed to natural environmental conditions. If proven effective, SIT using thiotepa-sterilised males may be incorporated into an integrated programme of vector control to combat dengue in Cuba.
Assuntos
Animais , Feminino , Masculino , Aedes/efeitos dos fármacos , Controle de Mosquitos/métodos , Tiotepa/farmacologia , Dengue/prevenção & controleRESUMO
The sterile insect technique (SIT) is a promising pest control method in terms of efficacy and environmental compatibility. In this study, we determined the efficacy of thiotepa-sterilised males in reducing the target Aedes aegypti populations. Treated male pupae were released weekly into large laboratory cages at a constant ratio of either 5:1 or 2:1 sterile-to-fertile males. A two-to-one release ratio reduced the hatch rate of eggs laid in the cage by approximately a third and reduced the adult catch rate by approximately a quarter, but a 5:1 release drove the population to elimination after 15 weeks of release. These results indicate that thiotepa exposure is an effective means of sterilising Ae. aegypti and males thus treated are able to reduce the reproductive capacity of a stable population under laboratory conditions. Further testing of the method in semi-field enclosures is required to evaluate the mating competitiveness of sterile males when exposed to natural environmental conditions. If proven effective, SIT using thiotepa-sterilised males may be incorporated into an integrated programme of vector control to combat dengue in Cuba.
Assuntos
Aedes/efeitos dos fármacos , Controle de Mosquitos/métodos , Tiotepa/farmacologia , Animais , Dengue/prevenção & controle , Feminino , MasculinoRESUMO
Este estudo compara, em coelhas, a influência dos agentes anti-proliferativos, mitocina C e tiotepa, na cicatrizaçäo de defeitos epiteliais corneanos. Com a utilizaçäo de um cilindro de plástico, foi possível manter por 5 minutos a área de defeito epitelial em contato com 1 ml de soluçäo de cloreto de sódio 0,9 por cento (olhos controles) ou com 1 ml de uma das soluçöes: mitomicina C 0,02 por cento, mitomicina C 0,04 por cento ou tiotepa 1:2000 (olhos tratados). Dentro das condiçöes desse estudo, conclui-se que a exposiçäo à soluçäo de tiotepa näo influencia a reparaçäo da lesäo, enquanto a soluçäo de mitomicina C a 0,02 por cento e a 0,04 por cento retardam significativamente a cicatrizaçäo da área desepitelizada