Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 451-480).

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Orientador: Katia Denise Saraiva Bresciani / Resumo: A Leishmaniose Visceral (LV) apresenta uma ampla distribuição geográfica em todos os continentes, representando um sério problema de Saúde Pública. Os flebotomíneos (Diptera, Psychodidae, Phlebotominae) são importantes insetos vetores de microrganismos patogênicos como Leishmania spp., Bartonella spp. e arbovírus (Vesiculovirus, Phlebovirus, Orbivirus), porém, estes insetos apresentam grande importância para a transmissão das leishmanioses em várias regiões do mundo, incluindo as Américas do Sul e Central. No Brasil, há duas espécies, até o momento, relacionadas com a transmissão da Leishmania infantum: a Lutzomyia longipalpis e a Lutzomyia cruzi. Infecções por Leishmania spp. são potencialmente zoonóticas e acometem homens e diversas espécies de animais silvestres e domésticos. Os cães são importantes hospedeiros, fontes de infecções e potenciais reservatórios, não só pelo estreito relacionamento ou convívio com os seres humanos, mas também por sua incapacidade imunológica em responder à doença com sucesso. O Ministério da Saúde no Brasil, preconiza para o diagnóstico da Leishmaniose Visceral Canina (LVC), o teste imunocromatográfico, como exame de triagem e o ensaio imunoenzimático, como confirmatório. Também recomenda o diagnóstico precoce e tratamento adequado dos casos humanos, o controle dos vetores, a eutanásia dos cães e atividades de educação em saúde nas áreas endêmicas para esta doença. Por tanto, foram instituídas ações de prevenção e controle da LV canina, na áre... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Visceral leishmaniasis (VL) has a wide geographical distribution on all continents, representing a serious Public Health problem. Sand flies (Diptera, Psychodidae, Phlebotominae) are important insect vectors of pathogenic microorganisms such as Leishmania spp., Bartonella spp. and arboviruses (Vesiculovirus, Phlebovirus, Orbivirus), however, these insects are of great importance for leishmaniasis transmission in various regions of the world, including South and Central America. In Brazil, there are two species related to the transmission of Leishmania infantum: Lutzomyia longipalpis and Lutzomyia cruzi. Leishmania spp. infections are potentially zoonotic and affect men and various species of wild and domestic animals. Dogs are important hosts, sources of infections and potential reservoirs, not only for their close relationship or contact with humans, but also for their immunological inability to successfully respond to the disease. The Health Ministry of Brazil recommends for the diagnosis of canine visceral leishmaniasis (CVL), the immunochromatographic test as a screening test and the enzyme immunoassay as confirmatory. It also recommends early diagnosis and appropriate treatment of human cases, vector control, dog euthanasia and health education activities in endemic areas for this disease. Therefore, prevention and control actions of canine VL were instituted in the urban area of municipality of Araçatuba, São Paulo, Brazil. / Doutor

Doctor of Philosophy / Department of Entomology / Marcelo Ramalho-Ortigao / Kun Yan Zhu / Microbial communities residing within the midgut of insect vectors play a critical role in the response to various zoonotic and human pathogens, and can directly alter the development and survival of the insects. Sand flies are the primary vector of Leishmania, the causative pathogen of leishmaniasis, a neglected tropical disease. Sand flies acquire many microbes from the soil where immature stages develop until emergence as adults. Gram-negative Pantoea agglomerans and gram-positive Bacillus subtilis are two bacteria commonly associated with sand fly populations. Here, I demonstrated that an EGFP- and a GFP-expressing version of these two bacteria localize to different compartments of the midgut; a phenomenon that is achieved, in part, to pH differences found across the length of the gut. Additionally, P. agglomerans is able to selectively induce midgut epithelial apoptosis while B. subtilis does not. This is accompanied by differential immune and homeostasis responses to both bacteria highlighted by immune pathway suppression via the Poor Immune Response upon Knock-in (Pirk) gene. These effects may actually be representative of a broader type of response to bacterial infection that might be present across several insect species. Finally, I demonstrated that during metamorphosis the sand fly relies, at least in part, upon the activation of multiple genes from the autophagy pathway to aid in generating adult tissues. More specifically, I demonstrate, using microscopy, the presence of ATG6 in the cytoplasm of developing midgut epithelial cells of the sand fly pupae.

Leishmaniasis is caused by infection with protozoan parasites within the genus Leishmania and, in the New World, is transmitted by the bites of female sand flies within the genus Lutzomyia. The occurrence of leishmaniasis in rodent species, the geographic distribution of sand fly species in Nicaragua, and environmental factors associated with the distribution of human cases of typical cutaneous leishmaniasis were investigated. Three hundred ninety five rodents representing 17 species were collected from 13 localities from August 2001–March 2006 and screened for Leishmania infections. One Heteromys desmarestianus and one Peromyscus mexicanus were found to be positive for leishmanial infections by PCR. This is the first report of Leishmania infections in rodents in Nicaragua. Five hundred fifty six sand flies representing 12 species were collected from 8 localities, including Lutzomyia hartmanni, a new record for this species in Nicaragua. The predominant sand fly species captured in western Nicaragua were Lutzomyia longipalpis and Lutzomyia evansi. The predominant species captured in central and eastern Nicaragua was Lutzomyia cruciata. The geographic distribution of sand flies in this study provides additional support to previouslypublished reports of suspected vectors of Leishmania species that cause typical and atypical forms of cutaneous leishmaniasis in Nicaragua. Distribution data of human cases of typical cutaneous leishmaniasis obtained from the Nicaraguan Ministry of Health, along with GIS and remotely sensed data of elevation, precipitation, temperature, soil types and land use/cover classes, were used to develop predictive logistic regression models for the presence or absence of human cases within 151 municipalities. Mean annual precipitation and land use/cover were determined to be the best environmental variable predictors for the occurrence of typical cutaneous leishmaniasis.

Orientador: Mara Cristina Pinto / Coorientador: Danilo Ciccone Miguel / Banca: Anderson de Sá Nunes / Banca: André Gonzaga dos Santos / Resumo: As leishmanioses são zoonoses causadas por protozoários flagelados do gênero Leishmania, transmitidos por insetos hematófagos denominados flebotomíneos. Dentre as espécies de flebotomíneos, Nyssomyia neivai está entre os principais transmissores do agente etiológico da Leishmaniose Tegumentar Americana (LTA) no estado de São Paulo, sendo incriminado como vetor da LTA também em outras áreas da América do Sul. Para localização dos hospedeiros e realização do repasto sanguíneo, os insetos hematófagos utilizam compostos voláteis emanados pelos mesmos, denominados cairomônios. Embora existam evidências de que a Leishmania possa influenciar a quantidade de sangue ingerida e a frequência de alimentação sanguínea dos flebotomíneos, aumentando a taxa de transmissão, não se sabe ao certo como o parasita pode afetar o comportamento dos insetos frente a hospedeiros infectados. O objetivo deste estudo foi investigar se camundongos BALB/c não infectados e infectados com Leishmania (Viannia) braziliensis apresentam diferença na atratividade para Ny. neivai, e nos voláteis emitidos; além disso, buscou-se avaliar o volume de sangue ingerido por Ny. neivai nos camundongos infectados e não infectados. Para avaliação de uma possível diferença de atratividade dos flebotomíneos frente a hospedeiros infectados ou não, foram realizados três modelos de teste: (a) preferência alimentar dos flebotomíneos quando colocados dois camundongos na mesma gaiola e com auxílio do corante azul de Evans como marca... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Leishmaniasis are zoonosis caused by flagellated protozoa of Leishmania genus, transmitted by hematophagous insects called sand flies. Among sand flies species, Nyssomyia neivai is one of the main vectors or etiological agent of American Cutaneous Leishmaniasis (ACL) in the state of São Paulo, being incriminated as vector of ACL also in other areas of South America. For location of hosts and blood meal, hematophagous insects use volatiles compounds released by the hosts, called kairomones. Although there are evidences that Leishmania may influence the quantity of blood ingested and the frequency of blood meal of the sand flies, increasing transmission rate, it is not known how the parasite can affect the behaviour of these insects against infected hosts. The aim of this study was to investigate if uninfected and Leishmania (Viannia) braziliensis infected BALB/C mice presents any difference of attractiveness to Ny. neivai, and in the released volatiles; besides that, was evaluated the blood volume ingested by Ny. neivai on infected and uninfected mice. To evaluate the attractiveness of sand flies to infected and not infected hosts, three types of trials were performed: (a) food preference of sand flies when placed two anesthetized mice in the same cage and Evans blue dye as a marker to help identification of the blood meal source of each sand fly; (b) mice as odour source in wind tunnel and (c) in Y-tube olfactometer. For the trials in the cages, feed females were individualized in micro tubes, macerated and homogenized for absorbance reading at 540 and 620 nm. Such reading allowed estimate the blood volume ingested for each feed female, from standard curves of absorbance versus blood volume previously obtained after... (Complete abstract click electronic access below) / Mestre

Doctor of Philosophy / Department of Entomology / Marcelo Ramalho-Ortigao / The emergence and reemergence of vector-borne diseases pose significant threats to humans and other animals worldwide. Although vector control relies mostly on insecticides, the emergence of insecticide resistance urges for the development of new strategies to control the spread of such diseases. For sand fly-transmitted leishmaniasis, Transmission Blocking Vaccines (TBV) may constitute a feasible strategy to impair Leishmania transmission from infected to uninfected vertebrate hosts. Moreover, sand fly saliva-based vaccines represent an alternative or complementary approach as these vaccines protect different mammalian hosts against Leishmania. Based on the potential use of sand fly molecules as vaccines against leishmaniasis, we assessed the potential of Phlebotomus papatasi midgut secreted proteins as TBV candidates and the expression variability of sand fly salivary gland genes. Regarding the TBV approach, we took advantage of the RNA interference (RNAi) technique to evaluate the effects of knocking down P. papatasi midgut-specific genes on Leishmania major development within the sand fly midgut. Whereas peritrophin 1 (PpPer1) knock down led to increased Le. major load by 39%, knocking down chitinase 1 (PpChit1) reduced Le. major load in P. papatasi midguts by 63%. Thus, our data strongly suggest that PpChit1 constitutes a potential target for TBV approaches against Leishmania transmission in endemic areas. Concerning protective vaccines based on salivary gland secreted proteins, we searched for expression polymorphism in selected salivary gland genes in natural and colonized populations of P. papatasi. Significant differences in salivary gland gene expression were not only exhibited in P. papatasi specimens collected in different geographic habitats but also seasonal difference in gene expression was displayed by specimens belonging to the same population. As antigen dose is an important component of immune responses, different doses of salivary protein inoculated into host skin may interfere with vaccine protection. Thus, the efficacy of sand fly saliva-based vaccine upon exposure to different salivary protein doses must be evaluated before deployment in endemic areas. Our data also ruled out some biotic factors as responsible for fine-tuning the expression of such genes. Overall, this dissertation makes significant contribution to the development of sand fly-based vaccines against leishmaniasis.

Leishmania of subgenus Sauroleishmania are parasites of reptiles, most often lizards, and are not pathogenic for humans. Therefore, they are neglected group of pathogens and their life cycle is not well-known. They are transmitted probably by ingestion of infected vector which is usually considered as sand flies of genus Sergentomyia (Diptera: Psychodidae). Sauroleishmania are traditionally denominated in Hypopylaria and it is expected that their development is limited to sand fly hindgut. The main aim of this work is to summarize the present knowledge about Sauroleishmania life cycle and to elucidate some aspects of their development in the vector and host. In the first part of thesis we studied development of four Sauroleishmania species in various sand flies of genera Sergentomyia and Phlebotomus. Late-stage infections of Leishmania (S.) adleri and L. (S.) hoogstraali were found in six and two sand fly species, respectively. Hypopylarian infections of Leishmania (S.) adleri were found in Se. schwetzi, P. papatasi and P. sergenti, while in P. argentipes, P. orientalis and P. duboscqi this Sauroleishmania migrated anteriorly in the midgut (peripylarian development). Similar type of development was observed also in P. argentipes and P. orientalis infected by Leishmania (S.) hoogstraali. Both L....

Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-09-12T18:39:06Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) yrllan_ribeiro_sincura.pdf: 1372727 bytes, checksum: 658bffd6fd52f41fbd207a828e8d098a (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-10-02T16:31:44Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) yrllan_ribeiro_sincura.pdf: 1372727 bytes, checksum: 658bffd6fd52f41fbd207a828e8d098a (MD5) / Made available in DSpace on 2018-10-02T16:31:44Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) yrllan_ribeiro_sincura.pdf: 1372727 bytes, checksum: 658bffd6fd52f41fbd207a828e8d098a (MD5) Previous issue date: 2018 / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / A leishmaniose visceral (LV) ? uma doen?a altamente letal quando n?o tratada e de car?ter reemergente. ? transmitida atrav?s da picada do flebotom?neo f?mea da esp?cie Lutzomyia longipalpis, inseto com grande distribui??o nas Am?ricas. O controle vetorial ? realizado atrav?s da aplica??o de inseticidas piretr?ides sint?ticos residuais de a??o r?pida sobre os insetos como a ?-cipermetrina e a deltametrina. Nos ?ltimos tempos tem se observado o surgimento de popula??es resistentes o que tem aumentado o interesse pela descoberta de novas mol?culas que possam ser utilizadas no controle de vetores. As plantas s?o um importante e promissor campo de pesquisa, uma vez que j? produzem mol?culas com a??o inseticida. Este estudo objetivou analisar a a??o inseticida de extratos de folhas e cascas de Protium heptaphyllum sobre Lutzomyia longipalpis selvagens. Para isso foram confeccionados extratos hidroalco?licos, etan?licos e ciclo- hex?nicos das folhas e cascas de Protium heptaphyllum. Nestes foram realizados estudos fitoqu?micos para prospec??o de classes de compostos secund?rios com a??o biol?gica. Os bioensaios foram realizados em potes pl?sticos adaptados e utilizou-se flebotom?neos Lu. longipalpis selvagens, oriundos da comunidade de Aroeira em Diamantina-MG. Obtivemos como resultado dos estudos fitoqu?micos, diversas classes de metab?litos secund?rios como terpenos, esteroides, taninos, flavonoides, alcaloides e saponinas, com destaque para os extratos de folhas onde foi observado um maior n?mero de classes em rela??o ?s cascas. Os bioensaios realizados evidenciaram uma a??o inseticida dos extratos hidroalco?licos e ciclo- hex?nicos que tiveram resultados estatisticamente semelhantes ? ?-cipermetrina. Apesar de composi??o qu?mica semelhante as demais, os extratos etan?licos apresentaram uma baixa atividade sobre os insetos. Com isso, conclu?mos que Protium heptaphyllum, possui atividade inseticida sobre Lu. longipalpis. Dessa forma, este estudo contribui com o desenvolvimento de m?todos de controle de insetos mais eficientes e menos agressivos aos humanos e outros animais. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biologia Animal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018. / Visceral leishmaniasis (VL) is a highly lethal disease when untreated and reemerging. It is transmitted through the bite of the female sand fly Lutzomyia longipalpis, a large-dose insect in the Americas. Vector control is performed through the application of fast acting residual synthetic pyrethroids on insects such as cypermethrin and deltamethrin. In recent times has been observed the emergence of resistant populations which has increased interest in the discovery of new molecules that can be used in the control of vectors. Plants are an important and promising field of research, since they already produce molecules with insecticidal action. This study aimed to analyze the insecticidal action of leaves and bark extracts of Protium heptaphyllum on wild Lutzomyia longipalpis. Hydroalcoholic, ethanolic and cyclohexanic extracts of the leaves and bark of Protium heptaphyllum were made. In these, phytochemical studies were found to identify groups of individuals with biological action. The bioassays were carried out in adapted plastic pots and wild Lu. longipalpis were used, originating from the community of Aroeira in Diamantina-MG. We obtained as a result of the phytochemical studies, several classes of secondary metabolites such as terpenes, steroids, tannins, flavonoids, alkaloids and saponins, especially leaf extracts where a greater number of classes were observed in relation to the bark. The bioassays performed showed an insecticidal action of hydroalcoholic and cyclohexane extracts that had statistically similar results to cypermethrin. Despite chemical composition similar to the others, the ethanolic extracts presented a low activity on the insects. From this investigation, we conclude that Protium heptaphyllum has insecticidal activity on Lu. longipalpis. Thus, this study contributes to the development of insect control methods that are more efficient and less aggressive to humans and other animals.