RESUMEN
In field tests conducted in south Florida to test grape juice as a bait for the Caribbean fruit fly, Anastrepha suspensa Loew, high numbers of Zaprionus indianus Gupta were captured in traps with aqueous grape juice. These experiments included comparisons of grape juice bait with established A. suspensa protein-based baits (ammonium acetate + putrescine lures, or torula yeast) or wine, a bait found previously to be attractive to Z. indianus. Effects of different preservatives (polypropylene glycol, polyethylene glycol, proxel, or sodium tetraborate) and bait age were also tested. Traps with grape juice baits captured more A. suspensa than unbaited traps, but more were captured in traps with grape juice plus preservative baits and the highest numbers were captured in traps containing the established protein-based baits. In contrast, grape juice baits without preservative that were prepared on the day of deployment (0 d) or that were aged for 3-4 d in the laboratory captured the highest numbers of Z. indianus, while solutions that were aged in the laboratory for 6 or 9 d captured fewer. Although these studies found that aqueous grape juice is a poor bait for A. suspensa, we found that actively fermenting aqueous grape juice may be an effective bait for Z. indianus.
Asunto(s)
Drosophilidae/efectos de los fármacos , Jugos de Frutas y Vegetales/análisis , Control de Insectos/métodos , Feromonas/farmacología , Tephritidae/efectos de los fármacos , Animales , Quimiotaxis , Drosophilidae/fisiología , Femenino , Florida , Masculino , Tephritidae/fisiología , Vitis/químicaRESUMEN
The larva of the drosophilid fly, Chymomyza costata, is probably the most complex metazoan organism that can survive submergence in liquid nitrogen (-196 °C) in a fully hydrated state. We examined the associations between the physiological and biochemical parameters of differently acclimated larvae and their freeze tolerance. Entering diapause is an essential and sufficient prerequisite for attaining high levels of survival in liquid nitrogen (23% survival to adult stage), although cold acclimation further improves this capacity (62% survival). Profiling of 61 different metabolites identified proline as a prominent compound whose concentration increased from 20 to 147 mM during diapause transition and subsequent cold acclimation. This study provides direct evidence for the essential role of proline in high freeze tolerance. We increased the levels of proline in the larval tissues by feeding larvae proline-augmented diets and found that this simple treatment dramatically improved their freeze tolerance. Cell and tissue survival following exposure to liquid nitrogen was evident in proline-fed nondiapause larvae, and survival to adult stage increased from 0% to 36% in proline-fed diapause-destined larvae. A significant statistical correlation was found between the whole-body concentration of proline, either natural or artificial, and survival to the adult stage in liquid nitrogen for diapause larvae. Differential scanning calorimetry analysis suggested that high proline levels, in combination with a relatively low content of osmotically active water and freeze dehydration, increased the propensity of the remaining unfrozen water to undergo a glass-like transition (vitrification) and thus facilitated the prevention of cryoinjury.
Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Errores Innatos del Metabolismo de los Aminoácidos/veterinaria , Criopreservación , Drosophilidae/efectos de los fármacos , Drosophilidae/fisiología , Nitrógeno/farmacología , 1-Pirrolina-5-Carboxilato Deshidrogenasa/deficiencia , Aclimatación/efectos de los fármacos , Errores Innatos del Metabolismo de los Aminoácidos/fisiopatología , Animales , Agua Corporal/efectos de los fármacos , Rastreo Diferencial de Calorimetría , Dieta , Conducta Alimentaria/efectos de los fármacos , Congelación , Vidrio , Larva/efectos de los fármacos , Larva/fisiología , Ósmosis/efectos de los fármacos , Análisis de Componente Principal , Prolina/metabolismo , Prolina Oxidasa/deficiencia , Análisis de SupervivenciaRESUMEN
The effect of an experimentally increased octopamine content (feeding flies with OA) on the levels of juvenile hormone (JH) degradation, dopamine (DA), and 20-hydroxyecdysone (20E) contents, oogenesis, and fecundity of wild type Drosophila flies has been studied. OA feeding of the flies was found to (1) cause a considerable decrease in JH degradation in females, but not males, of D. melanogaster and D. virilis; (2) have no effect on DA content in D. melanogaster and D. virilis; (3) increase 20E contents in D. virilis females; (4) decrease to a large extent the number of vitellogenic (stages 8-10) and mature (stage 14) oocytes in D. virilis; and (5) decrease the fecundity of D. melanogaster and D. virilis. A possible mechanism of action of OA as a neurohormone on the reproductive function of Drosophila is discussed.
Asunto(s)
Agonistas alfa-Adrenérgicos/farmacología , Drosophilidae/efectos de los fármacos , Octopamina/farmacología , Oogénesis/efectos de los fármacos , Animales , Dopamina/análisis , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/fisiología , Drosophilidae/fisiología , Ecdisterona/análisis , Femenino , Fertilidad/efectos de los fármacos , Hormonas Juveniles/análisis , Hormonas Juveniles/metabolismo , Masculino , Factores de TiempoRESUMEN
A basically new system has been developed to screen carcinogens in Drosophilidae, which is based on somatic mutagenesis and recombination. The system may induce tumors in Drosophilidae, which are recorded in adult insects. The test uses recessive mutation in the suppressor gene of growth of warts (wts) tumors. The new system is sensitive to a wide spectrum of mutagenic carcinogens that are naturally encountered. The sensitivity of the system to polycyclic aromatic hydrocarbons and aromatic amides is higher than that of classical tests. Dominant p53 gene mutation that ceases mutagen-induced apoptosis has been shown to increase the incidence of wts tumors by many times. The magnitude of the effect depends on the rate of mutant p53 expression. The increasing effect of p53 mutation extends to both somatic recombination and point mutations and deletions at the wts locus.
Asunto(s)
Pruebas de Carcinogenicidad , Carcinógenos/toxicidad , Cisplatino/análogos & derivados , Drosophilidae/efectos de los fármacos , Drosophilidae/genética , Animales , Antineoplásicos/toxicidad , Apoptosis , Benzo(a)pireno/toxicidad , Cisplatino/toxicidad , Interpretación Estadística de Datos , Dimetilsulfóxido/toxicidad , Proteínas de Drosophila , Femenino , Genes Supresores , Genes p53 , Genotipo , Heterocigoto , Masculino , Mutación , Mutación Puntual , Proteínas Quinasas , Sensibilidad y Especificidad , Verrugas/genéticaRESUMEN
Heat shock protein induction is often associated with a cellular response to a harmful environment or to adverse life conditions. The main aims of our study were (1) to evaluate the cytotoxic potential of cypermethrin; and (2) to investigate the suitability of stress-induced heat shock protein Hsp70 as a biomarker for environmental pollutants in transgenic Drosophila melanogaster (Hsp70-lacZ)Bg(9). Different concentrations of cypermethrin (0.002, 0.2, 0.5 and 50.0 p.p.m.) were mixed with food. Third instar larvae of transgenic Drosophila melanogaster were allowed to feed on these mixtures for different time intervals (2, 4, 6, 12, 24 and 48 h). Following feeding, hsp70 induction and tissue damage were evaluated. In the highest concentration treatment group (50 p.p.m.), 100% larval mortality was recorded after 12 h exposure. Hsp70 was found to be induced even at the lowest concentration (0.002 p.p.m.) of the insecticide, while tissue damage was observed in the larvae exposed for 48 h. While an insignificant decline in hsp70 expression was observed in the larvae exposed to cypermethrin at a dietary concentration of 0.002 p.p.m. after 48 h compared with those exposed for 24 h, in the next two higher concentrations of the toxicant, a similar but significant decline in hsp70 expression was evident in the exposed larvae after 48 h. The present study reveals the cytotoxic potential of cypermethrin and further proposes that hsp70 induction in transgenic Drosophila melanogaster could be used as a sensitive biomarker in risk assessment.