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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Invasion d’Aedes albopictus dans les milieux forestiers tropicaux et potentiel pour l’émergence de virus zoonotiques au Brésil / Invasion of Aedes albopictus in tropical forest and potential for the emergence of zoonotic viruses in Brazil

Pereira Dos Santos, Taissa 19 March 2019 (has links)
Les zoonoses émergentes sont en augmentation au cours des dernières décennies. Ainsi, il y est urgent de comprendre les mécanismes de cette émergence, en particulier d’étudier les facteurs écologiques sous-jacents qui déterminent les transferts de ces maladies de l’animal à l’homme.Originaire d’Asie, le moustique tigre Aedes albopictus est arrivé au Brésil dans les années 80 et s’est établi dans 60% des villes brésiliennes. Les forêts brésiliennes sont considérées comme un point chaud de la biodiversité mondiale, abritant des centaines d'arbovirus zoonotiques. Ces forêts que, par fois, cercles des grandes agglomérations urbaines, souffrent de la transformation du paysage réalisé par l’homme, un terreau idéal pour l'apparition de zoonoses. Cette espèce représente une préoccupation majeure pour la transmission d’arbovirus épidémiques (Dengue, Chikungunya, Zika) mais également une menace potentielle pour l’émergence de maladies zoonotiques en raison de sa présence dans les interfaces ville / forêt, de son comportement alimentaire opportuniste et de sa compétence vectorielle pour nombreux virus. Ainsi, Ae. albopictus pourrait potentiellement jouer le rôle de vecteur pont pour le transfert en milieu urbain de arbovirus zoonotiques qui circulent dans les forêts brésiliennes. Dans cette étude, nous évaluons le potentiel de cette espèce à servir de vecteur de pont entre la faune et l'homme. Pour cette proposition (i) Nous avons effectué une recherche et une analyse bibliographiques portant sur trois éléments clés permettant d’évaluer la capacité de ce moustique à assurer le transfert interspécifique des arbovirus dans les zones sylvatiques : 1) la capacité à exploiter les sites de reproduction larvaire naturels, 2) le comportement alimentaire et 3) la compétence vectorielle pour les dif férentes arbovirus. (ii) Nous avons étudié sur le terrain la colonisation, la dispersion, le comportement trophic et l'impact sur la biodiversité d'Ae. albopictus dans l'interface ville / forêt au Brésil. Ce travail de terrain a été réalisé à partir de dix écosystèmes de fragments de forêts dans trois Biomes au Brésil: 1) Biome Amazonia dans la réserve forestière d'Adolpho Ducke à Manaus; 2) Biome Mata Atlantica dans la réserve forestière de Pedra Branca à Rio de Janeiro, dans les fragments de forêt urbaine à Salvador, Serra, Belo Horizonte et dans les fragments de forêt rurale à Domingos Martins, Simonésia, Casimiro de Abreu, Marica-RJ; Biome Cerrado dans la forêt de Morro dos Macacos à Goiania. Dans cette thèse nous avons confirmé qu’Ae. albopictus a la capacité de coloniser des sites de reproduction naturels avec un comportement alimentaire opportuniste et une claire préférence pour les sources de sang humain, suivi par d'autres mammifères et oiseaux. Nous observons que le processus de colonisation et de dispersion est limité à la bordure de la forêt avec un impact sur la composition des espèces dans ces environnements. Nous avons observé également que ce moustique est capable de transmettre 13 arbovirus dans notre recherche bibliografic, mais aucun arbovirus n’a été détecté chez des moustiques prélevés lors du travail de terrain. Globalement, nos résultats confirment et estiment le rôle potentiel d’Ae. albopictus comme vecteur pont des maladies zoonotiques aux interfaces forêt / ville au Brésil. Ces travaux ouvrent un domaine de recherche dans lequel de nouvelles investigations pourraient évaluer le risque potentiel de propagation des maladies zoonotiques des zones forestières aux zones urbaines, dans le but de limiter les futures émergences virales. / Zoonotic emerging diseases are increasing during the last decades. There is an urgent need to understand the mechanisms of this emergence, in particular to study the underlying ecological factors determining spill-over events, the transfer from animals to humans. Being native from Asia, the tiger mosquito Aedes albopictus arrived to Brazil in the 80’s being nowadays established in 60% of brazilian cities. Brazilian forests are considered a hotspot of wildlife biodiversity, harbouring hundreds of zoonotic arboviruses, suffering human landscape transformation and surrounding large urban cities, an optimal breeding ground for the emergence of zoonotic diseases. This species represents a major concern for the transmission of epidemic arboviruses (dengue, chikungunya, Zika) but also a potential threat for the emergence of zoonotic diseases due to its presence in urban/forest interfaces, its opportunistic feeding behavior and its vector competence to transmit numerous viruses. Thus, Ae. albopictus might potentially participate as a bridge vector for the transfer to urban environments of zoonotic arboviruses that are circulating on Brazilian forests. In this study we evaluate the potential of this species to act as a bridge vector between wildlife and humans. For this propose (i) we performed a bibliographic research and analysis focusing on three key components for assessing the ability of a mosquito to ensure interspecies transfer of arboviruses in sylvatic areas: 1) the capacity to exploit natural larval breeding sites, 2) blood-feeding behaviour and 3) the vector competence for arboviruses. (ii) We investigated from fieldwork the colonization, dispersion, host feeding and potential impact of biodiversity patterns of Ae. albopictus in the urban/forest interface in Brasil. This field work was realized from ten forest-fragments ecosystems in tree Brazilians Biome: Biome Amazonia in Adolpho Ducke forest reserve-Manaus; Biome Mata Atlantica in Pedra Branca forest reserve- Rio de Janeiro, in the urban forest fragment Salvador, Serra, Belo Horizonte and in the rural forest fragment Domingos Martins, Simonésia, Casimiro de Abreu, Marica-RJ; Biome Cerrado in Morro dos Macacos forest – Goiania. This work confirmed that Ae. albopictus has the capacity to colonize natural breeding sites with the opportunistic feeding behavior with a preference for human blood sources, followed by other mammals and birds. We observe that the colonization and dispersion process is limited to the edge forest with an impact in species composition in this environments. We observed that this mosquitos is vector competence for 13 arbovirus from bibliographic recherché, but no arbovirus was detected from fildework collected mosquitos. Globally our results confirm and estimates the potential role of Ae. albopictus to act as a bridge vector of zoonotic diseases at the forest/urban interfaces in Brazil. This work opens a research area in which further investigations may assess the potential spill-over risk of zoonotic disease from forested to urban areas with the aim to mitigate potential future viral emergences.
12

Análise da atividade locomotora de Aedes aegypti e Aedes albopictus (Diptera: Culicidae) do Parque Municipal do Piqueri São Paulo, SP / Analysis of the locomotor activity of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) of the Piqueri Municipal Park São Paulo, SP

Pancetti, Filipe Gabriel Menezes 23 August 2017 (has links)
O estudo de mosquitos é extremamente importante, pois muitos são considerados vetores de diversos patógenos transmissíveis ao homem. Aedes aegypti e Aedes albopictus são responsáveis por transmitir arbovírus, como os da dengue, chikungunya, zika e febre amarela urbana, no mundo. Neste trabalho foram empregados Ae. aegypti e Ae. albopictus para: analisar a atividade locomotora de machos, fêmeas virgens e fêmeas inseminadas naturalmente; comparar a atividade locomotora de fêmeas injetadas intratoracicamente com extrato de glândulas acessórias (AG) de machos co e heteroespecíficos; e verificar a taxa de inseminação de fêmeas injetadas com glândulas acessórias de machos co e heteroespecíficos, quando são posteriormente expostas a seus machos coespecíficos. Os mosquitos foram coletados em ovitrampas instaladas no Parque Municipal do Piqueri, Zona Leste da cidade de São Paulo, durante o outono e a primavera de 2015 e outono de 2016. Após a emergência dos adultos, estes foram transferidos para quatro gaiolas matrizes separadas por espécie e sexo, dos quais obtivemos machos e fêmeas virgens de cada espécie. Em outras duas gaiolas foram agrupadas por espécie, 40 fêmeas e 40 machos para cópula por 24 horas para obtermos fêmeas inseminadas naturalmente. Posteriormente, todos os mosquitos foram transferidos para uma incubadora por quatro dias para análise da atividade locomotora. Na comparação de fêmeas injetadas com glândulas acessórias, foram extraídas as glândulas de machos de Ae. aegypti e Ae. albopictus e estas injetadas intratoracicamente em fêmeas co e heteroespecíficas. Todas as fêmeas injetadas foram transferidas para uma incubadora por três dias. Para a análise dos dados foram utilizados os testes estatísticos F e T e ANOVA. Após a atividade locomotora, as fêmeas injetadas foram expostas a seus machos coespecíficos e posteriormente tiveram suas espermatecas dissecadas para verificar a presença de espermatozoides a fim de analisar a taxa de inseminação. Nos machos, fêmeas virgens e fêmeas inseminadas naturalmente de Ae. aegypti e Ae. albopictus, o padrão da atividade locomotora foi diurno e bimodal no outono e na primavera. Em Ae. aegypti machos a atividade foi mais evidente no outono e em Ae. albopictus na primavera. Nas fêmeas de Ae. aegypti virgens a atividade foi mais evidente que nas inseminadas naturalmente em ambas as estações. Nas fêmeas de Ae. albopictus não houve diferença na atividade das virgens e inseminadas. Nas fêmeas de Ae. aegypti injetadas com AG a atividade locomotora foi diurna, com padrão unimodal e menos marcada. Nas fêmeas de Ae. albopictus injetadas com AG não houve diferença. Na taxa de inseminação, somente Ae. albopictus fêmeas injetadas com AG heteroespecíficas apresentaram espermatozoides após cópula coespecífica. Este estudo contribui para compreensão do comportamento de mosquitos vetores como Ae. aegypti e Ae. albopictus / The study of mosquitoes is extremely important, since many are considered vectors of several pathogens transmissible to man. Aedes aegypti and Aedes albopictus are responsible for transmitting arboviruses, such as dengue, chikungunya, zika and urban yellow fever, in the world. This study employed Ae. aegypti and Ae. albopictus to: analyze the locomotor activity of males, virgin females and females naturally inseminated; compare the locomotor activity of females injected intratoracically with extract of accessory glands (AG) of co and heterospecific males; and verify the rate of insemination of females injected with accessory glands of co and heterospecific males when later exposed to their co-specific males. The mosquitoes were collected in ovitraps installed in Piqueri Municipal Park, East of São Paulo city, during the autumn and spring of 2015 and autumn of 2016. After the emergence of adults, they were transferred to four cages, separated by species and sex from which we obtained virgin males and females of each species. In the other two cages, they were grouped by species, 40 females and 40 males for mating during 24 hours to obtain naturally inseminated females. Thereafter, all the mosquitoes were transferred to an incubator for four days to the locomotor activity analysis. In the comparison of females injected with accessory glands, the male glands of Ae. aegypti and Ae. albopictus were extracted and injected intratoracically into co and heterospecific females. All injected females were transferred to an incubator for three days. For the analysis, the statistical tests F and T and ANOVA were used. After the locomotor activity, the injected females were exposed to their co-specific males and later had their spermathecas dissected to verify the presence of spermatozoa in order to analyze the insemination rate. In males, virgin and naturally inseminated females of Ae. aegypti and Ae. albopictus, the pattern of locomotor activity was diurnal and bimodal in autumn and spring. Aedes aegypti males activity was more evident in autumn and in Ae. albopictus in spring. In virgin females of Ae. aegypti the activity was more evident than in the naturally inseminated in both seasons. In females of Ae. albopictus, there was no difference in the activity of virgin and inseminated. In females of Ae. aegypti injected with AG the locomotor activity was diurnal, with a unimodal and less marked pattern. In the females of Ae. albopictus injected with AG there was no difference. In the insemination rate, only Ae. albopictus females injected with heterospecific AGs presented spermatozoa after coespecific mating. This study contributes to the understanding of mosquito vectors behavior such as Ae. aegypti and Ae. albopictus
13

Análise da atividade locomotora de Aedes aegypti e Aedes albopictus (Diptera: Culicidae) do Parque Municipal do Piqueri São Paulo, SP / Analysis of the locomotor activity of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) of the Piqueri Municipal Park São Paulo, SP

Filipe Gabriel Menezes Pancetti 23 August 2017 (has links)
O estudo de mosquitos é extremamente importante, pois muitos são considerados vetores de diversos patógenos transmissíveis ao homem. Aedes aegypti e Aedes albopictus são responsáveis por transmitir arbovírus, como os da dengue, chikungunya, zika e febre amarela urbana, no mundo. Neste trabalho foram empregados Ae. aegypti e Ae. albopictus para: analisar a atividade locomotora de machos, fêmeas virgens e fêmeas inseminadas naturalmente; comparar a atividade locomotora de fêmeas injetadas intratoracicamente com extrato de glândulas acessórias (AG) de machos co e heteroespecíficos; e verificar a taxa de inseminação de fêmeas injetadas com glândulas acessórias de machos co e heteroespecíficos, quando são posteriormente expostas a seus machos coespecíficos. Os mosquitos foram coletados em ovitrampas instaladas no Parque Municipal do Piqueri, Zona Leste da cidade de São Paulo, durante o outono e a primavera de 2015 e outono de 2016. Após a emergência dos adultos, estes foram transferidos para quatro gaiolas matrizes separadas por espécie e sexo, dos quais obtivemos machos e fêmeas virgens de cada espécie. Em outras duas gaiolas foram agrupadas por espécie, 40 fêmeas e 40 machos para cópula por 24 horas para obtermos fêmeas inseminadas naturalmente. Posteriormente, todos os mosquitos foram transferidos para uma incubadora por quatro dias para análise da atividade locomotora. Na comparação de fêmeas injetadas com glândulas acessórias, foram extraídas as glândulas de machos de Ae. aegypti e Ae. albopictus e estas injetadas intratoracicamente em fêmeas co e heteroespecíficas. Todas as fêmeas injetadas foram transferidas para uma incubadora por três dias. Para a análise dos dados foram utilizados os testes estatísticos F e T e ANOVA. Após a atividade locomotora, as fêmeas injetadas foram expostas a seus machos coespecíficos e posteriormente tiveram suas espermatecas dissecadas para verificar a presença de espermatozoides a fim de analisar a taxa de inseminação. Nos machos, fêmeas virgens e fêmeas inseminadas naturalmente de Ae. aegypti e Ae. albopictus, o padrão da atividade locomotora foi diurno e bimodal no outono e na primavera. Em Ae. aegypti machos a atividade foi mais evidente no outono e em Ae. albopictus na primavera. Nas fêmeas de Ae. aegypti virgens a atividade foi mais evidente que nas inseminadas naturalmente em ambas as estações. Nas fêmeas de Ae. albopictus não houve diferença na atividade das virgens e inseminadas. Nas fêmeas de Ae. aegypti injetadas com AG a atividade locomotora foi diurna, com padrão unimodal e menos marcada. Nas fêmeas de Ae. albopictus injetadas com AG não houve diferença. Na taxa de inseminação, somente Ae. albopictus fêmeas injetadas com AG heteroespecíficas apresentaram espermatozoides após cópula coespecífica. Este estudo contribui para compreensão do comportamento de mosquitos vetores como Ae. aegypti e Ae. albopictus / The study of mosquitoes is extremely important, since many are considered vectors of several pathogens transmissible to man. Aedes aegypti and Aedes albopictus are responsible for transmitting arboviruses, such as dengue, chikungunya, zika and urban yellow fever, in the world. This study employed Ae. aegypti and Ae. albopictus to: analyze the locomotor activity of males, virgin females and females naturally inseminated; compare the locomotor activity of females injected intratoracically with extract of accessory glands (AG) of co and heterospecific males; and verify the rate of insemination of females injected with accessory glands of co and heterospecific males when later exposed to their co-specific males. The mosquitoes were collected in ovitraps installed in Piqueri Municipal Park, East of São Paulo city, during the autumn and spring of 2015 and autumn of 2016. After the emergence of adults, they were transferred to four cages, separated by species and sex from which we obtained virgin males and females of each species. In the other two cages, they were grouped by species, 40 females and 40 males for mating during 24 hours to obtain naturally inseminated females. Thereafter, all the mosquitoes were transferred to an incubator for four days to the locomotor activity analysis. In the comparison of females injected with accessory glands, the male glands of Ae. aegypti and Ae. albopictus were extracted and injected intratoracically into co and heterospecific females. All injected females were transferred to an incubator for three days. For the analysis, the statistical tests F and T and ANOVA were used. After the locomotor activity, the injected females were exposed to their co-specific males and later had their spermathecas dissected to verify the presence of spermatozoa in order to analyze the insemination rate. In males, virgin and naturally inseminated females of Ae. aegypti and Ae. albopictus, the pattern of locomotor activity was diurnal and bimodal in autumn and spring. Aedes aegypti males activity was more evident in autumn and in Ae. albopictus in spring. In virgin females of Ae. aegypti the activity was more evident than in the naturally inseminated in both seasons. In females of Ae. albopictus, there was no difference in the activity of virgin and inseminated. In females of Ae. aegypti injected with AG the locomotor activity was diurnal, with a unimodal and less marked pattern. In the females of Ae. albopictus injected with AG there was no difference. In the insemination rate, only Ae. albopictus females injected with heterospecific AGs presented spermatozoa after coespecific mating. This study contributes to the understanding of mosquito vectors behavior such as Ae. aegypti and Ae. albopictus
14

"Observações ecológicas de Aedes albopictus (Diptera: Culicidae) em áreas de proteção ambiental e urbana da periferia na Grande São Paulo" / Ecological observations of Aedes albopictus (Diptera: Culicidae) in urban and preserved areas in the outskirts of Greater Sao Paulo.

Urbinatti, Paulo Roberto 10 December 2004 (has links)
RESUMO Urbinatti PR. Observações ecológicas de Ae. albopictus (Diptera: Culicidae) em áreas de proteção ambiental e urbana na periferia da Grande São Paulo. São Paulo; 2004. [Tese de Doutorado – Faculdade de Saúde Pública da Universidade de São Paulo]. Objetivos. Contribuir para o conhecimento da ecologia de uma população de Ae. albopictus em área de proteção ambiental e urbanizada. Métodos. Para avaliar aspectos da infestação desse culicídeo, escolheram-se duas áreas próximas, o Parque Ecológico do Tietê (PET), em área de proteção ambiental, (ambientes 1 e 2) e outra antrópica, Jardins São Francisco e Piratininga (ambientes 1 e 2), na Zona Leste da Capital. A primeira etapa da pesquisa foi desenvolvida no PET, de abril de 2001 a março de 2002 e a segunda foi nos Jardins São Francisco e Piratininga, de abril de 2002 a março de 2003. Com a finalidade de medir e comparar a infestação de Ae. albopictus entre os dois ambientes do PET e Jardins, utilizaram-se, 10 larvitrampas e 10 ovitrampas, sendo instaladas no peridomicílio e com monitoramento quinzenal no PET e a cada dez dias nos Jardins. Foram efetuadas coletas de amostras de água para análise de parâmetros físicos e químicos e de fauna associada. Resultados. Ae. albopictus foi à espécie mais freqüente em relação as demais coletadas, nos criadouros naturais e artificiais, correspondendo a 97,70 % e 92,50 % do total de imaturos, respectivamente no PET, Jardins São Francisco e Piratininga. Observou-se que os índices de densidade e positividade das ovitrampas e larvitrampas, no PET apresentaram valores elevados quando comparados aos Jardins São Francisco e Piratininga. Verificou-se correlação positiva significante entre a densidade de larvas e pupas de Ae. albopictus coletada em larvitrampas e as temperaturas ambiente e da água nos pneus nas duas áreas. Observou-se diferença estatisticamente significante entre a densidade de larvas de Ae. albopictus nas larvitrampas dos ambientes 1 e 2 do PET e Jardins, na presença e ausência de fauna associada.Conclusões. A presença freqüente de Ae. albopictus tanto em áreas de proteção ambiental como em alterada, reforça a evidência de sua ampla valência ecológica em colonizar ecótopos naturais e artificiais. Diante deste comportamento e aliado a competência e capacidade vetora, espera-se que os resultados dessa pesquisa possam fornecer informações que possibilitem subsidiar ações de controle caso esse mosquito represente ameaças à Saúde Pública. Descritores: Aedes albopictus, vetor, imaturos, ovitrampa, larvitrampa, urbanização / SUMMARY Urbinatti PR. Ecological observations of Aedes albopictus (Diptera: Culicidae) in urban and preserved areas in the outskirts of Greater Sao Paulo. São Paulo; 2004. [Tese de Doutorado – Faculdade de Saúde Pública da Universidade de São Paulo]. Objective. To contribute to the knowledge of the ecology of the Ae. albopictus population both in a protected and in an urban environment. Methods. Two different environments were chosen to evaluate aspects of the infestation of the East End of the city: a protected environment - the Parque Ecológico do Tietê (PET) divided into environments 1 and 2, and another anthropogenically altered one - the Jardins São Francisco and Piratininga, divided in the same way. The first step of the investigation was undertaken in PET between April 2001 and March 2002 and the second step in the Jardins, between April 2002 and March 2003. To measure and compare Ae. Albopictus infestation as between PET and Jardins, 10 larvitraps and 10 ovitraps were installed around a domiciliary area with monitoring every 15 days in PET and every 10 days in the Jardins. The analysis of water samples for their chemical and physical parameters and associated fauna was undertaken. Results. Ae. albopictus was the most frequently collected species, both in artificial and natural breeding sites, accounting for 97.70% and 92.50% of the total of immature specimens collected in PET and in the Jardins, respectively. As regards the positive rates of ovitraps and larvitraps, PET presented higher values than the Jardins. There was a significant correlation between larval and pupal densities in the larvitraps and the temperature of water in tires and sites and a significant difference between larval densities in the larvitraps of environments 1 and 2 in both PET and Jardins, as regards the presence and absence of associated fauna. Conclusions. The frequent presence of Ae. albopictus in protected areas and in altered ones reinforces the evidence of its ecological adaptability in the colonization of both natural and artificial environments. This behavior associated with its competence and vectorial capacity should contribute with information that will be useful for control actions if these insects come to represent a public health threat. Key words: Aedes albopictus, vector, immature, ovitrap, larvitrap, urbanization
15

Interaction tripartite Aedes albopictus, Wolbachia, arbovirus : mécanismes moléculaires et cellulaires de l’interférence microbienne / Aedes albopictus, Wolbachia, arbovirus tri-partite interaction : molecular and cellular mechanisms of microbial interference

Saucereau, Yoann 09 December 2016 (has links)
L'émergence et la réémergence d'arboviroses au niveau mondial sont responsables de pathologies pouvant causer le décès des personnes infectées et elles sont transmises par des moustiques vecteurs. En l'absence de prophylaxies efficaces, les moyens de lutte actuels reposent essentiellement sur l'utilisation d'insecticides, mais ces derniers sont nocifs pour les écosystèmes et des résistances apparaissent chez la plupart des vecteurs. Il devient nécessaire de développer des moyens de lutte alternatifs. La découverte du potentiel antiviral de certaines bactéries symbiotiques des moustiques a ouvert de nouvelles voies pour le développement de la lutte biologique. Mon projet de thèse porte sur l'étude des mécanismes déclenchés dans l'interaction tripartite entre le moustique tigre Aedes albopictus, ses deux souches de Wolbachia, wAlbA et wAlbB, et deux arbovirus (Chikungunya et Dengue) dont il est un vecteur avéré. Originaire d'Asie du Sud Est, il est devenu une préoccupation majeure de santé publique, notamment pour son fort pouvoir invasif, ayant colonisé les quatre autres continents, ainsi que pour son statut de vecteur de nombreux arbovirus et certaines filaires. Les résultats de nos travaux ont montré un potentiel antiviral de la bactérie chez les moustiques infectés par Wolbachia en comparaison des moustiques aposymbiotiques. Les analyses du protéome et du transcriptome ont permis d'identifier certains mécanismes cellulaires et moléculaires du moustique spécifiquement modulés par la présence de Wolbachia ou des arbovirus, mais aussi deux partenaires microbiens simultanément. Ces approches ont permis de mettre en évidence le rôle important du métabolisme dans le maintien de l'intégrité cellulaire et du système immunitaire pour contrôler l'infection virale. En outre, nos résultats révèlent un patron de compétition entre bactérie et arbovirus contribuant à la compréhension du phénomène interférence observé chez les moustiques / The emergence and reemergence of arboviruses in the world are responsible for pathologies that can cause the death of infected and they are transmitted by mosquitoes. In absence of effective prophylaxis, current control methods are essentially based on the use of insecticides, but they are harmful to ecosystems and resistances appear in most vectors. It becomes necessary to develop alternative means of control. Discovery of the antiviral potential of some symbiotic bacteria mosquito has opened new avenues for the development of biological control. My PhD project focuses on the study of mechanisms triggered in the tripartite interaction between the Asian tiger mosquito, Aedes albopictus, two strains of Wolbachia, and wAlbA wAlbB and two Arbovirus (Chikungunya and Dengue) of which he is a proven vector. Native to Southeast Asia, it has become a major public health concern, particularly for its highly invasive, have colonized the four other continents, as well as its status vector many arboviruses and some wire. The results of our work has shown antiviral potential of bacteria in mosquitoes infected with Wolbachia in comparison aposymbiotic mosquitoes. The analyzes of the proteome and transcriptome have identified certain cellular and molecular mechanisms of mosquito specifically modulated by the presence of Wolbachia or arboviruses, but also two microbial partners simultaneously. These approaches have helped to highlight the important role of metabolism in maintaining cell integrity and immune system to control the viral infection. In addition, our results reveal a pattern competition between bacteria and arbovirus contributing to understanding the phenomenon interference observed in mosquitoes
16

"Observações ecológicas de Aedes albopictus (Diptera: Culicidae) em áreas de proteção ambiental e urbana da periferia na Grande São Paulo" / Ecological observations of Aedes albopictus (Diptera: Culicidae) in urban and preserved areas in the outskirts of Greater Sao Paulo.

Paulo Roberto Urbinatti 10 December 2004 (has links)
RESUMO Urbinatti PR. Observações ecológicas de Ae. albopictus (Diptera: Culicidae) em áreas de proteção ambiental e urbana na periferia da Grande São Paulo. São Paulo; 2004. [Tese de Doutorado – Faculdade de Saúde Pública da Universidade de São Paulo]. Objetivos. Contribuir para o conhecimento da ecologia de uma população de Ae. albopictus em área de proteção ambiental e urbanizada. Métodos. Para avaliar aspectos da infestação desse culicídeo, escolheram-se duas áreas próximas, o Parque Ecológico do Tietê (PET), em área de proteção ambiental, (ambientes 1 e 2) e outra antrópica, Jardins São Francisco e Piratininga (ambientes 1 e 2), na Zona Leste da Capital. A primeira etapa da pesquisa foi desenvolvida no PET, de abril de 2001 a março de 2002 e a segunda foi nos Jardins São Francisco e Piratininga, de abril de 2002 a março de 2003. Com a finalidade de medir e comparar a infestação de Ae. albopictus entre os dois ambientes do PET e Jardins, utilizaram-se, 10 larvitrampas e 10 ovitrampas, sendo instaladas no peridomicílio e com monitoramento quinzenal no PET e a cada dez dias nos Jardins. Foram efetuadas coletas de amostras de água para análise de parâmetros físicos e químicos e de fauna associada. Resultados. Ae. albopictus foi à espécie mais freqüente em relação as demais coletadas, nos criadouros naturais e artificiais, correspondendo a 97,70 % e 92,50 % do total de imaturos, respectivamente no PET, Jardins São Francisco e Piratininga. Observou-se que os índices de densidade e positividade das ovitrampas e larvitrampas, no PET apresentaram valores elevados quando comparados aos Jardins São Francisco e Piratininga. Verificou-se correlação positiva significante entre a densidade de larvas e pupas de Ae. albopictus coletada em larvitrampas e as temperaturas ambiente e da água nos pneus nas duas áreas. Observou-se diferença estatisticamente significante entre a densidade de larvas de Ae. albopictus nas larvitrampas dos ambientes 1 e 2 do PET e Jardins, na presença e ausência de fauna associada.Conclusões. A presença freqüente de Ae. albopictus tanto em áreas de proteção ambiental como em alterada, reforça a evidência de sua ampla valência ecológica em colonizar ecótopos naturais e artificiais. Diante deste comportamento e aliado a competência e capacidade vetora, espera-se que os resultados dessa pesquisa possam fornecer informações que possibilitem subsidiar ações de controle caso esse mosquito represente ameaças à Saúde Pública. Descritores: Aedes albopictus, vetor, imaturos, ovitrampa, larvitrampa, urbanização / SUMMARY Urbinatti PR. Ecological observations of Aedes albopictus (Diptera: Culicidae) in urban and preserved areas in the outskirts of Greater Sao Paulo. São Paulo; 2004. [Tese de Doutorado – Faculdade de Saúde Pública da Universidade de São Paulo]. Objective. To contribute to the knowledge of the ecology of the Ae. albopictus population both in a protected and in an urban environment. Methods. Two different environments were chosen to evaluate aspects of the infestation of the East End of the city: a protected environment - the Parque Ecológico do Tietê (PET) divided into environments 1 and 2, and another anthropogenically altered one - the Jardins São Francisco and Piratininga, divided in the same way. The first step of the investigation was undertaken in PET between April 2001 and March 2002 and the second step in the Jardins, between April 2002 and March 2003. To measure and compare Ae. Albopictus infestation as between PET and Jardins, 10 larvitraps and 10 ovitraps were installed around a domiciliary area with monitoring every 15 days in PET and every 10 days in the Jardins. The analysis of water samples for their chemical and physical parameters and associated fauna was undertaken. Results. Ae. albopictus was the most frequently collected species, both in artificial and natural breeding sites, accounting for 97.70% and 92.50% of the total of immature specimens collected in PET and in the Jardins, respectively. As regards the positive rates of ovitraps and larvitraps, PET presented higher values than the Jardins. There was a significant correlation between larval and pupal densities in the larvitraps and the temperature of water in tires and sites and a significant difference between larval densities in the larvitraps of environments 1 and 2 in both PET and Jardins, as regards the presence and absence of associated fauna. Conclusions. The frequent presence of Ae. albopictus in protected areas and in altered ones reinforces the evidence of its ecological adaptability in the colonization of both natural and artificial environments. This behavior associated with its competence and vectorial capacity should contribute with information that will be useful for control actions if these insects come to represent a public health threat. Key words: Aedes albopictus, vector, immature, ovitrap, larvitrap, urbanization
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Competição e dispersão de Aedes (Stegomyia) aegypti (Linnaeus, 1762) e Aedes (Stegomyia) albopictus (Skuse, 1894) (Diptera: Culicidae) em áreas de ocorrência no município de João Pessoa - PB / Competition and dispersal of Aedes (Stegomyia) aegypti (Linnaeus, 1762) and Aedes (Stegomyia) albopictus (Skuse, 1894) (Diptera: Culicidae) in areas of occurrence in the city of João Pessoa - PB

Leandro, Renata da Silva 31 May 2012 (has links)
Made available in DSpace on 2015-09-25T12:18:54Z (GMT). No. of bitstreams: 1 Renata da Silva Leandro.pdf: 1211259 bytes, checksum: 2999635188f9dc2c5318f621049e78fc (MD5) Previous issue date: 2012-05-31 / Aedes (Stegomyia) aegypti (Linnaeus, 1762) and Aedes (Stegomyia) albopictus (Skuse, 1894) are introduced species in Brazil, with wide geographic distribution. A. aegypti is found predominantly in urban environments, while A. albopictus in rural, semi-wild and wild. These stand out today as public health problems due to their roles as transmitters of dengue and yellow fever. The inter and intraspecific competition are important stress factors for both species since their larvae develop in natural reservoirs and / or artificial, which vary in size, food availability over time and population density, which can lead to a limitation on the amount of food available, and encourage individuals to compete for resources. In the present study evaluated the competition, in the laboratory, these species, their life cycles, and also the distribution of forest environment, and urban interface, in addition to their household and peridomestic distributions. For this purpose, a survey was conducted, where it was decided to present their data in two parts, the first chapter we evaluated the competition and coparada biology of Aedes aegypti and Aedes albopictus and the second was treated patterns of geographical distribution of two species of genus Aedes in urban areas, interface and kills the city of João Pessoa - PB. / Aedes (Stegomyia) aegypti (Linnaeus, 1762) e Aedes (Stegomyia) albopictus (Skuse, 1894) são espécies introduzidas no Brasil, com ampla distribuição geográfica. A. aegypti é encontrado predominantemente em ambientes urbanos, enquanto A. albopictus em ambientes rurais, semi-silvestres e silvestres. Estes se destacam hoje como problemas em saúde pública, devido aos seus papéis como transmissores da dengue e febre amarela. A competição intra e interespecífica são fatores de estresse relevantes para ambas às espécies uma vez que suas larvas se desenvolvem em reservatórios naturais e/ou artificiais, que variam em tamanho, disponibilidade de alimento ao longo do tempo e densidade populacional, que pode levar a uma limitação na quantidade de alimento disponível, e estimular os indivíduos a competirem pelos recursos. No presente estudo avaliou-se a competição, em laboratório, destas espécies, seus ciclos de vida e, ainda, a distribuição em ambiente de Mata, interface e área urbana, além das suas distribuições intradomiciliar e peridomiciliar. Para tanto, foi realizada uma pesquisa, onde se optou apresentar seus dados em duas partes, no primeiro capítulo avaliou-se a competição e biologia coparada do Aedes aegypti e Aedes albopictus e no segundo tratou-se dos padrões de distribuição geográfica das duas espécies do gênero Aedes em área urbana, de interface e mata do município de João Pessoa PB.
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Etiologie virale des syndromes fébriles : recherche, identification et caractérisation des arbovirus circulant au Gabon / Viral etiology of febrile syndromes : research, identification and characterization of arboviruses circulating in Gabon

Caron, Mélanie 28 November 2013 (has links)
Depuis 2007, le Gabon est régulièrement confronté à des infections par les virus Chikungunya (CHIKV) et Dengue (DENV). Au total, près de 4300 prélèvements provenant de patients se présentant avec un syndrome fébrile algique, en phase clinique aiguë, ont pu être collectés et analysés pour la période de 2007 à 2010. En effet, deux importantes épidémies concomitantes de CHIKV et de DENV ont sévi au Gabon (i.e. Libreville en 2007 et Franceville en 2010). Entre ces deux flambées épidémiques, de nombreux cas sporadiques d'infection à CHIKV ou à DENV ont continué à être enregistrés à travers le pays. Des cas de co-infection à CHIKV/DENV ont également été diagnostiqués lors des deux flambées épidémiques. Ces deux arbovirus se sont ainsi propagés en quelques années dans un mouvement de nord-ouest à sud-est à travers le pays. L’étude plus avancée des cas de co-infection à CHIKV/DENV a pu démontrer que ce phénomène pouvait survenir soit de manière simultanée soit séquentielle au cours du repas sanguin d'Aedes albopictus, principal vecteur du CHIKV et du DENV au Gabon.(…)En conclusion, ce travail de thèse décrit précisément la survenue brutale d’épidémies imputables à plusieurs arbovirus circulant simultanément au Gabon et responsables de nombreux cas cliniques se présentant sous la forme d'un syndrome fébrile algique. La co-circulation de ces virus suggère l’apparition d’une dynamique de type épidémique/endémique et implique un problème de santé publique latent dans cette région d’Afrique, voire dans l’ensemble de la sous-région d’Afrique Centrale. / Following to the first simultaneous Chikungunya (CHIKV) and Dengue (DENV) viruses outbreak in 2007, an active surveillance of febrile syndromes was set up in Gabon, a central African country. During a three-year period, we observed a rapid spread of CHIKV and DENV in a southward movement from north-west to south-east of the country. Indeed, CHIKV and DENV have disseminated within a non-immune population, widely favored by the extraordinary capacity of Aedes albopictus vector to colonize diverse environments and to replace local mosquito’s species. In 2010, a second outbreak occurred in Gabon with further CHIKV/DENV co-infections in both human and mosquito. This is the first documented evidence of co-infection in a wild-caught Aedes albopictus. Additionally, an underlying Zika (ZIKV) virus epidemic transmission by the same invasive vector was retrospectively recorded during the outbreak in 2007. These data reveal an unusual ZIKV natural life cycle, occurring in an urban environment and potentially representing a new arboviral emerging threat from Aedes albopictus.(…)In conclusion, these data highlighted the recent introduction and rapid dissemination of CHIKV and DENV in Gabon. The Aedes albopictus vector has shown its extraordinary capacity to sustain epidemic transmissions, leading to arboviral co-circulations (i.e. CHIKV, DENV-2, DENV-1, DENV-3, ZIKV) and notably to some CHIKV/DENV-2 co-infection cases. This multiple arboviral circulation suggests an epidemic/endemic dynamic in Gabon, involving a latent public health problem in this region of Africa.
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The effects of temperature and humidity on the eggs of Aedes aegypti (L.) and Aedes albopictus (Skuse) in Texas

Dickerson, Catherine Zindler 15 May 2009 (has links)
Causative influences that impact the separation of Ae. aegypti and Ae. albopictus populations in different geographic areas were determined, as well as how they are affected by the abiotic conditions as seen in the habitats they frequent in Texas. The eggs of Ae. albopictus and Ae. aegypti collected from McAllen and Brownsville, Texas, and laboratory populations of these two species were subjected to 25 different temperature and relative humidity conditions for up to three months. In most treatments, Ae. aegypti eggs had a greater percent hatch than Ae. albopictus, regardless of temperature or relative humidity. With an increase in relative humidity, the percent hatch for both species increased, but at the higher temperatures of 32° and 35°C the amount of time the eggs were exposed to those temperatures had a greater negative effect on the percent hatch than did the positive effect of increase in relative humidity. The surface area, volume and surface-area-to-volume ratio of Ae. aegypti and Ae. albopictus eggs with and without the chorionic egg pad, and the size of the chorionic egg pad were calculated for fifty eggs of each species of mosquito from populations collected in McAllen and Brownsville and from the laboratory populations. Ae. aegypti had a larger egg volume, and a larger surface area; but, it is likely their larger egg pad compensates for this high surface-area-to-volume ratio by holding moisture along the egg’s surface and that the egg pad is associated with the high desiccation resistance seen in Ae. aegypti eggs. Development rates for both species of mosquitoes from populations collected in Galveston and Brownsville, Texas, and laboratory populations were produced by measuring the development time from a hatched egg to the adult at seven temperatures. The temperature optima (28°-33°C) were similar for all populations; however, the rate of development for Ae. aegypti was significantly faster at the temperature optima. It is likely that this faster development rate in the Ae. aegypti population helps to maintain a population in climates that have this range of temperatures given that Ae. albopictus is a superior competitor in the larval and adult stages.
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Effects of species interactions and productivity on aquatic macroinvertebrate diversity and community composition in tree holes patterns and mechanisms /

Yee, Donald A. Juliano, Steven A. January 2006 (has links)
Thesis (Ph. D.)--Illinois State University, 2006. / Title from title page screen, viewed on May 14, 2007. Dissertation Committee: Steven A. Juliano (chair), Roger C. Anderson, L. Philip Lounibos, Wade A. Nichols, William L. Perry. Includes bibliographical references (leaves 145-162) and abstract. Also available in print.

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