41 research outputs found

    Experimental infection of Aedes albopictus (Diptera : Culicidae) larvae with the xiphidiocercariae of a hematolechid

    Get PDF
    Aedes albopictus larvae were exposed, either individually or in groups, to different concentrations of xiphidiocercariae of Haematoloechus sp. for parasitological studies. It was observed the acute lethal effect and some aspects of the host-parasite relationship, such as delay or progress in the host life cycle, the number and location of the metacercariae in the host, adult host malformations and the amount of metacercariae required to cause death. A delay in the cycle and a high mortality rate was in general observed. Inside the larvae, the metacercariae were found predominantly in the thorax, abdominal segments and in the head, along with a reduced number in the anal lobe and cervix. It was shown that in addition to the quantity, of metacercariae present, their location in the larvae was also relevant in the determination of mortality and anomalies. Malformed adults developed from larvae containing from one to three metacercariae.97457357

    Vector competence of Culex quinquefasciatus Say, 1823 exposed to different densities of microfilariae of Dirofilaria immitis (Leidy,1856)

    Get PDF
    Vector competence of Cuter quinquefascictus Say, 1823 exposed to different densities of microfilariae of Dirofilaria immitis (Leidy, 1856). The metropolitan region of Recife, Brazil is endemic for Dirofilaria immitis and has an environment favorable to the development of Culex quinquefasciatus. The goal of this study was to evaluate the vector competence of the Cx. quinquefasciatus RECIFE population for D. immitis transmission. A total of 2.104 females of Cx. quinquefasciatus RECIFE population were exposed to different densities of D. immitis microfilariae blood meals, ranging from 1,820 to 2,900 mf/ml of blood, in a natural membrane apparatus. The results showed a variation between 92.3% and 98.8% of females fed. The exposure of the Cx. quinquefasciatus RECIFE population to different densities of microfilariac did not influence the mortality of the mosquitoes. Infective larvae from D. immitis were observed in the Malpighian tubules beginning on the 12(th) day, whereas larvae were observed in the head and proboscis beginning oil the 13(th) day following infection. The vector efficiency index (VEI) presented by the mosquitoes ranged front 7.8 to 56.5. The data demonstrates that the Cx. quinquefasciatus RECIFE population has great potential for the transmission of D. immitis, as it allowed the development of the filarid until the infectious stage at the different densities of microfilariae to which it was exposed.52465866

    Desatando a trama das redes assistenciais sobre drogas: uma revisão narrativa da literatura

    Get PDF
    Acalorados debates sobre determinados modelos de tratamento para usuários de drogas ocorrem no âmbito da academia, das políticas públicas, além da mídia. A rede assistencial sobre drogas é apresentada neste contexto como um importante mecanismo, mas sua construção torna-se um desafio. Assim, realizou-se uma análise crítica da literatura acadêmica acerca das redes assistenciais sobre drogas, na forma de uma revisão narrativa, visando levantar seus desafios e possibilidades de consolidação. Os resultados encontrados foram: a) uma escassez de estudos específicos sobre a rede assistencial sobre drogas; b) cobertura insuficiente e desintegrada frente à demanda de tratamento; c) necessidade de se repensar o papel dos Centros de Atenção Psicossocial para Álcool e outras Drogas, visando seu fortalecimento, expansão, melhoria estrutural e readequação de práticas; d) ausência de análises críticas sobre o processo de construção dos modelos assistenciais sobre drogas nos serviços públicos; e, e) responsabilidade do Estado em fornecer melhores alternativas ao panorama encontrado, avançando no fortalecimento das ações intersetoriais, articulação do cuidado e no aprimoramento das condições de trabalho

    Differential predation of the planarian Dugesia tigrina on two mosquito species under laboratory conditions

    No full text
    Two experiments were performed on the predation of the planarian Dugesia tigrina (Girard) upon 2 mosquito prey species, Aedes albopictus and Culex quinquefasciatus. Bioassays were carried out in sectioned tires with 2 liters of water. In the Ist experiment, predation was evaluated using 4, 8, and 12 mature planarians against 40 2nd-stage larvae of each mosquito species alone. In the 2nd experiment, the same 3 predator densities were used with a pool composed of 20 2nd-stage larvae of each mosquito species. In the Ist experiment, final corrected mortality of Ae. albopictus reached 89.1, 98.8, and 99.6% and final corrected mortality of Cx. quinquefasciatus reached 29.4, 48.0, and 53.0%, respectively, with 4, 8, and 12 planarians. In the 2nd experiment and when subjected to the: density of 4 planarians, Ae. albopictus was more susceptible to predation, with a selectivity index of 0.87, whereas this index was 0.13 for Cx. quinquefasciatus. Predation was more intensive during the Ist 4 days of the experiments, when most larvae were in the 2nd and 3rd stages. We observed that Cx. quinquefasciatus larvae were faster than Ae. albopictus in reacting to planarian contacts, resulting in more success in escaping from the predator attacks.171818

    COMPARATIVE STUDIES ON AEDES AEGYPTI AND AEDES ALBOPICTUS ADULT FEMALES TRESPASSING COMMERCIAL NETS

    No full text
    The abilities of Aedes aegypti and Ae. albopictus females in trespassing 5 different commercial nets, 2 nets impregnated with deltamethrin or permethrin and 3 non-impregnated nets (Guarany, Perame, and Ricca), were compared. The evaluating parameters were their percent trespassing success, the median trespassing time (TT(50)), and the relation between mosquito wing sizes and their trespassing success. Some mosquito behavioral traits were also observed. The trespassing success, directly related to opening areas, was found to be lower with impregnated nets for both species. The differences between the mosquito species were significant among all the nets except Ricca. Aedes albopictus showed a very high success rate in trespassing the non-impregnated Perame net and a lower success rate in trespassing Guarany. Aedes albopictus also showed a very high success rate in trespassing pyrethroid-impregnated nets. The TT(50) values for the Ricca and Guarany nets were not significantly different between the species, but a significantly lower TT(50) value was found for the net with the largest opening (Ricca). The smaller wingspan of Ae. albopictus seems to explain the higher trespassing success of this species.26111211

    Polytene chromosome analysis of a population of Simulium pertinax (Diptera: Simuliidae)

    No full text
    Cytological studies were performed on a semi-natural population of Simulium pertinax from Morungaba, State of Sao Paulo, Brazil. This species has 2n = 6 chromosomes, being one pair of metacentric and two pairs of submetacentric chromosomes. Polytene chromosome maps of the three autosomes from larval salivary gland cells were obtained. The chromosomes of this population have conspicuous centromeric regions and high morphological stability. Asynaptic regions were rare. Inversions and morphological altered bands were not detected in the population (N = 102). A comparison of the band patterns of S. pertinax maps with the standard for the subgenus Simulium showed many similarities in all chromosome arms.191475
    corecore