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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.
231

Katepsiny B ptačí schistosomy Trichobilharzia regenti / Cathepsins B of the bird schistosome, Trichobilharzia regenti

Dolečková, Kateřina January 2010 (has links)
1. Overview Schistosomes have achieved first position among parasitic helminths, because some of them are the etiological agents of a serious human parasitic disease, schistosomiasis, which affects over 200 million people in tropical and subtropical countries (WHO, 2001). Other schistosomatids, such as the bird flukes of the genus Trichobilharzia, have also implications for human health. Although they can mature only in specific hosts (birds), their invasive larvae - cercariae - are able to penetrate also human skin due to chemical signals similar to those present on bird skin (Haas and van de Roemer 1998). Repeated infections result in an inflammatory reaction of the skin called cercarial dermatitis. Due to the increasing number of outbreaks all around the world, cercarial dermatitis is cons disease (Kolářová 2007idered as re-emerging ; Larsen et al. 2004). Among schistosomes, Trichobilharzia regenti is the only species described so far having a unique migration route within vertebrate hosts: after penetration of the skin, the invasive larvae enter peripheral nerves and continue via the spinal cord and central nervous system to the nasal cavity of birds, causing neuromotor disorders or paralyses of birds and even experimental mammals (Hrádková...
232

Revisão taxonômica e filogenia do gênero Noctiliostrebla Wenzel, 1966 (Diptera, Streblidae) / Taxonomic revision and phylogeny of the genus Noctiliostrebla Wenzel, 1966 (Diptera, Streblidae)

Alcântara, Daniel Máximo Corrêa de 02 June 2014 (has links)
Noctiliostrebla Wenzel, 1966 pertence a Streblidae, uma família de moscas parasitas exclusivas de morcegos, e compreende atualmente quatro espécies divididas em dois grupos, grupo A: Noctiliostrebla dúbia (Rudow, 1871) e N. traubi Wenzel, 1966; e grupo B: N. aitkeni Wenzel, 1966 e N. maai Wenzel, 1966. O gênero está incluído dentro da subfamília Trichobiinae, junto com Paradyschiria Speiser, 1900, sugerido como seu grupo-irmão hipotético. Com uma classificação sistemática complicada e poucos estudos taxonômicos, Noctiliostrebla caracteriza-se como um grupo muito homogêneo e de difícil distinção entre suas espécies. Restrito ao continente americano, exibe um alto grau de especificidade em relação às duas únicas espécies de morcegos do gênero Noctilio Linnaeus, 1766, N. albiventris Desmarest, 1818 e N. leporinus (Linnaeus, 1758). Não existem trabalhos filogenéticos para Noctiliostrebla, sendo que, os únicos estudos envolvendo Streblidae foram feitos para propor uma hipótese de relacionamentos entre as famílias de Hippoboscoidea. O projeto tem como objetivos realizar a revisão taxonômica do gênero Noctilostrebla e reconstruir uma hipótese de relacionamento entre as espécies do gênero, utilizando caracteres morfológicos e um conjunto de dados moleculares composto por três genes mitocondriais (12S, COI e cytB) e um gene nuclear (CAD). Dois métodos de análise foram empregados: análise de parcimônia, com pesagem igual dos caracteres, e análise de máxima verossimillhança. As análises foram realizadas com dados morfológicos e moleculares separados, enquanto os dados moleculares foram analisados com genes concatenados e separados em mitocondriais e nucleares. Como resultados, as quatro espécies já descritas foram consideradas válidas, sendo aqui redescritas, e outras seis novas espécies foram descritas. Do total de onze espécies, cinco são parasitas restritos de N. albiventris e seis de N. leporinus. As estruturas abdominais forneceram os únicos caracteres diagnósticos encontrados para separação entre as espécies. Tanto a análise morfológica como a molecular recuperaram Noctiliostrebla como monofilético e corroboraram a divisão do gênero em dois clados morfologicamente distintos. As análises com genes mitocondriais e nucleares foram incongruentes com relação a alguns clados, o que pode ser um indicativo de histórias filogenéticas diferentes. Os resultados obtidos para Noctiliostrebla apresentaram semelhanças com as hipóteses consideradas para os hospedeiros / Noctiliostrebla Wenzel 1966 belongs to Streblida, a family of batflies, and currently comprises four species divided into two groups, group A: Noctiliostrebla dubia (Rudow, 1871) and N. traubi Wenzel, 1966; Group B: N. aitkeni. Wenzel, 1966 and N. maai Wenzel, 1966. The genus is included within the Trichobiinae subfamily, along with Paradyschiria Speiser, 1900, suggested as your hypothetical sister group. With a complicated systematic classification and a few taxonomic studies, Noctiliostrebla is characterized as a very homogeneous group and difficult to distinguish between their species. Restricted to the American continent, exhibits a high degree of specificity with the only two bats species of the genus Noctilio Linnaeus, 1766, N. albiventris Desmarest, 1818 and N. leporinus (Linnaeus, 1758). There are no phylogenetic works with Noctiliostrebla and the only studies involving Streblidae were made to propose a relationship hypothesis among Hippoboscoidea families. The project aims to conduct a taxonomic revision of the Noctilostrebla genus and to rebuild a relationship hypothesis among Noctilostrebla species using morphological and molecular data set, with three mitochondrial genes (12S, COI and cytB) and one nuclear gene (CAD). Two analysis methods were used: parsimony with equal weighting of characters and lielihood. The analyses were performed using morphological and molecular data separate, while the molecular data were analyzed with concatenated genes and separated into mitochondrial and nuclear genes. As a result, the four described species were considered valid being here redescribed, and six new species have been described. Of all eleven species, five are restricted parasites of N. albiventris and six are restricted parasites of N. leporinus. The abdominal structures provided the only diagnostic characters found for separation of the species. Both morphological and molecular analysis recovered a monophyletic Noctiliostrebla and supported the division of the genus into two distinct clades. The analyses of mitochondrial and nuclear genes showed inconsistent clades, which may be indicative of different phylogenetic histories. The results obtained for Noctiliostrebla showed similarities with the assumptions for the hosts
233

Développement multipolaire en harmoniques sphériques et propagation des incertitudes appliqués à la modélisation de source de rayonnement en compatibilité électromagnétique / Expansions in spherical harmonics and propagation of uncertainty applied ot the near-field characterization of EMC sources

Li, Zhao 28 November 2017 (has links)
Avec les progrès de la technologie, la densité de puissance des appareils électriques augmente, ce qui conduit à une augmentation des interférences électromagnétiques entre deux systèmes d’électroniques de puissance. Ces interférences peuvent engendrer un dysfonctionnement des appareillages. Afin d’éviter de tels problèmes, une grande quantité de vérifications expérimentaux sont nécessaires après le développement d’un prototype, ce qui conduira à un surcoût important dans son cycle industriel. Cette thèse a pour objectif de prendre en compte des problèmes de compatibilité électromagnétique en champ proche dès la phase de conception d’un produit. Ceci est basé sur le développement en harmoniques sphériques du rayonnement parasite engendré par les dispositifs ou les composants d’un dispositif. Les coefficients harmoniques d’un dispositif permettent non seulement de modéliser ses champs proches par une source ponctuelle, mais également de déterminer le couplage inductif avec les autres. Dans ce contexte, la méthode du développement multipolaire est étudiée théoriquement, numériquement (par le logiciel Flux3D) et expérimentalement dans ce travail. Dans ce document, le nouveau système de mesure automatisé est présenté et différentes approches liées à la solution de ce problème sont étudiées, tels que le choix optimal d’origine du développement, la compensation d’erreurs des mesures dues aux sources secondaires, l’étude de propagation d’incertitude dans le problème inverse et prise en compte d’informations a priori, etc. / With the advances in technology, the power density of electrical equipment is increasing, which leads to an increase in electromagnetic interference between two power electronic systems. This interference may cause the electronic equipment to malfunction. In order to avoid such problems, a large number of experimental verifications are necessary after the development of a prototype, which leads to a significant additional cost in its industrial cycle. This thesis aims at taking into account the problems of near-field electromagnetic compatibility in the design phase of a product. The method is based on the development in spherical harmonics of the parasitic radiation generated by the devices or the components of the device. The harmonic coefficients of a device make it possible not only to model its near field by a punctual source, but also to determine the inductive coupling with the others. In this context, the multipole expansion method is studied theoretically, numerically (by the software Flux3D) and experimentally in this work. In this document, the new automated measuring system is presented and different approaches related to the solution of this problem are then studied, such as the optimal choice of the development origin, the error compensation of the measurements due to the secondary sources, the study of the propagation of uncertainty in the inverse problem and how to take into account the a priori information, etc.
234

Mimicry and speciation in the parasitic finches of Africa

Jamie, Gabriel Adam January 2017 (has links)
In this thesis, I study a radiation of brood-parasitic finch species, the indigobirds and whydahs (genus Vidua), that occur across Africa. Host colonisation is tightly linked to speciation in Vidua because of their remarkable capacity to imprint on their hosts, with mating traits and host preferences being influenced by the parasite's early environment. The challenge of explaining why the radiation has diversified to the extent it has therefore simplifies to understanding why only certain potential host species have been successfully colonised. Following on from the introduction (Chapter 1), I begin by critically examining the logic with which mimicry in the natural world can be conceptually organized (Chapter 2). This creates a “mimicry landscape” in which to situate the mimetic adaptations of hosts exhibited by Vidua. The framework can be used to contrast and draw parallels between these and other mimetic adaptations present in the natural world. In Chapter 3, I review the literature on begging call mimicry and development across all avian brood parasite species. I outline the conditions under which we expect begging call mimicry to evolve, and when we expect it to develop primarily through genetic or environmental cues. This provides clear predictions for what we expect to occur in Vidua finches, which are tested in Chapters 4 and 5. In Chapter 4, I quantify the mimicry of host nestlings by Vidua in detail. I provide the first quantitative evidence that Vidua nestlings mimic the begging calls and show for the first time that Vidua are imperfect mimics of their hosts. In Chapter 5, I simulate the colonisation of a new host by transferring Vidua eggs into the nest of a new host species. I monitor Vidua survival in the foreign host environment and test several hypotheses about what explains differences in chick survival. I find that Vidua survive poorly in the new nest environment and that they do not show adaptive plasticity in begging calls or head movements. This poor survival occurs despite there being minimal differences in the diets each host species feeds their young. Finally, in Chapter 6, I carry out a comparative analysis on the evolution of estrildid mouth markings. Estrildid finches are the hosts of Vidua and so provide the landscape of potential ecological niches that Vidua may colonise and adapt to. I demonstrate that the host family shows strong phylogenetic signal in mouth marking traits, and find no evidence that ecological factors such as light environment or predation pressure has shaped estrildid mouth marking evolution. The work in this thesis highlights how difficult successfully colonising new hosts is for Vidua finches. Vidua must mimic hosts in multiple traits (mouth markings, begging calls, head movements) to obtain sufficient amounts of food from host parents. Overall, habitat filters, the complex and diverse begging displays of estrildid nestlings, the discriminatory behaviour of estrildid parents against mismatching chicks and the lack of adaptive plasticity in begging displays by Vidua together help explain why the Vidua radiation consists of only 19 species rather than many more or fewer.
235

The costs and benefits of sociality explored in wild Bornean orangutans (Pongo pygmaeus wurmbii)

O'Connell, Caitlin Ann 28 February 2018 (has links)
The socioecological model offers a framework for attempting to explain variation in sociality based on differences in ecological and social factors such as resource distribution, predation pressure, and infanticide risk. Orangutans are unusual among higher primates in their low degree of sociality and are considered to be semi-solitary. Their limited social behavior is thought to be a result of weak predation pressure on these large-bodied apes, coupled with the low and unpredictable fruit productivity that is characteristic of their habitat. Orangutans do come together occasionally, and there appears to be variability in the gregariousness of different populations. Orangutans present a unique opportunity to examine both social and solitary conditions within a single population to test predictions regarding the costs and benefits of sociality. This study assesses the ecological and social context in which social parties occur in Gunung Palung National Park on the island of Borneo. The potential costs of these associations are evaluated using behavioral and physiological markers of stress and parasite infection patterns. Fruit availability is predicted to influence the frequency of social associations, with sociality increasing when fruit availability is high. While the socioecological model predicts that female orangutans display reduced sociality, this should affect females in different reproductive (and hence, energetic) states differently. The results of this study confirmed that fruit availability influences the occurrence of social events and revealed adolescent females to be the most social age-sex class. Adolescent females displayed the most affiliative behaviors and engaged in notable sexual rituals with flanged males. They sought and maintained social associations with others, particularly their mothers. Despite evident signs of anxiety, adolescent females did not display elevation in the stress hormone cortisol under social conditions, while adult females and flanged males did. Intestinal parasites were widespread in this population, and the prediction for elevated parasite prevalence in more social classes was unsupported. This study revealed a greater degree of gregariousness than orangutans are typically credited with, and highlights the adolescent period as behaviorally distinct and socially rich for female orangutans who face unique challenges as members of a semi-solitary species with high levels of sexual coercion. / 2020-02-28T00:00:00Z
236

Parasitismo em novilhas 1/2 Angus 1/2 Nelore mantidas em sistema silvipstoril

Bello, Hornblenda Joaquina Silva January 2018 (has links)
Orientador: Ricardo Velludo Gomes de Soutello Soutello / Resumo: Foi avaliada a influência do sombreamento em sistema silvipastoril em relação ao grau de parasitismo por endoparasitas e ectoparasitas em novilhas Angus Nelore, analisando o grau de infecção por helmintos nos animais e quantificação de larvas na pastagem, o grau de infestação por carrapatos e mosca-dos-chifres, parâmetros hematológicos e o ganho de peso destes animais. O experimento foi conduzido na Agência Paulista de Tecnologia dos Agronegócios (APTA) de Andradina, com 72 novilhas ½ Angus ½ Nelore, com peso médio inicial de 276 ± 5,67 kg e 09 meses de idade, em uma área total de 25 hectares, dividida em 12 piquetes, com três tratamentos e quatro repetições. O delineamento experimental foi em blocos casualizados, sendo o tratamento 1, sistema de pastejo convencional sem sombra e os tratamentos 2 e 3 com linhas simples e linhas triplas de eucalipto, respectivamente. As novilhas receberam tratamento antiparasitário somente dois meses antes do início do experimento. As avaliações foram realizadas a cada 28 dias, de junho de 2017 a abril de 2018. Os dados foram coletados por meio da pesagem dos animais, coletas de fezes para exames quantitativos e qualitativos de helmintos gastrintestinais, coleta de sangue para hemograma, contagens de larvas infectantes de helmintos na pastagem, de mosca dos chifres e de carrapatos nos animais. Os dados climáticos foram gerados pela estação meteorológica localizada próxima a área experimental. Os dados obtidos foram submetidos a análise de vari... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The influence of shading in silvopastoral system in relation to the degree of parasitism by endoparasites and ectoparasites in Angus Nellore heifers was evaluated, analyzing the degree of infection by helminths in the animals and quantification of larvae in the pasture, the degree of infestation by ticks and horn fly, hematological parameters and the gain of weight of these animals. The experiment was carried out at the Paulista Agency of Agribusiness Technology (APTA) of Andradina, with 72 heifers ½ Angus ½ Nelore, with a mean initial weight of 276 ± 5.67 kg and 9 months of age, in a total area of 25 hectares, divided into 12 pickets, with three treatments and four replicates. The experimental design was randomized blocks, with treatment 1, conventional shade grazing system and treatments 2 and 3 with single lines and triple eucalyptus lines, respectively. Heifers received antiparasitic treatment only two months before the start of the experiment. The evaluations were performed every 28 days, from June 2017 to April 2018. Data were collected by weighing the animals, stool samples for quantitative and qualitative examinations of gastrointestinal helminths, blood collection for blood counts, larval counts infecting helminths in grazing, fly horns and ticks in animals. The climatic data were generated by the meteorological station located near the experimental area. The data were submitted to analysis of variance and Tukey test at the significance level of 5% of probability and... (Complete abstract click electronic access below) / Mestre
237

A estrutura da angiosperma endoparasita Pilostyles ulei (Apodanthaceae): interface e impacto no lenho de Mimosa spp / The structure of the endoparasite angiosperm Pilostyles ulei (Apodanthaceae): interface and impact on Mimosa ssp xylem

Amaral, Marina Milanello do 29 June 2007 (has links)
Essa Dissertação de Mestrado é apresentada em três capítulos que originarão três futuras publicações. Os capítulos só não estão sob a forma de artigos porque, para isso, tanto texto como figuras teriam de ser reduzidos. Nosso intuito é apresentar o trabalho de forma mais pormenorizada, gerando assim uma discussão mais rica, que poderá posteriormente gerar outros trabalhos mais específicos. Pilostyles (Apodanthaceae) são angiospermas endoparasitas de caules de Fabaceae e um dos mais notáveis exemplos de redução do corpo vegetativo. Apesar da ocorrência de muitas espécies na América do Sul, os relatos concentram-se em espécies de outras regiões, como Estados Unidos, Austrália e Oriente Médio. Para aperfeiçoar a interpretação desse corpo vegetativo, o primeiro capítulo desse trabalho investiga anatomicamente Pilostyles ulei, uma espécie sul-americana, em três hospedeiros diferentes de Fabaceae: Mimosa foliolosa var. multipinna, M. maguirei (ambas com ocorrência em Minas Gerais) e M. setosa var. paludosa (com ocorrência na Bahia). São abordados a constituição e o posicionamento do corpo da parasita, bem como a plasticidade da zona de contato entre parasita e hospedeiro. Fragmentos de caules parasitados e saudáveis foram processados e proporcionaram observações principalmente em Microscopia Óptica (tanto colorações simples e duplas quanto testes histoquímicos e macerações) e Microscopia Confocal. As imagens produzidas a partir de ambos os tipos de microscopia foram usadas conjuntamente e reunidas para interpretar a estrutura tridimensional que a parasita adquire em seu hospedeiro. Além disso, foi utilizada a Microscopia Eletrônica de Transmissão com o intuito de procurar por outros tipos celulares parasitas (p.ex. elementos crivados). Tem-se que as pequenas flores que rompem a periderme do hospedeiro estão conectadas a massas de corpo vegetativo parasita. As massas, formadas por parênquima (sem função de armazenamento), ocupam principalmente a região floemática dos hospedeiros Mimosoidea. A partir delas, grupos de elementos traqueais retorcidos cercados por células parenquimáticas - denominadas extensores - direcionam-se ao interior do xilema secundário hospedeiro. Nossos dados apontam que o corpo vegetativo se expande de maneira disjunta e constante, organizando-se igualmente nas três espécies hospedeiras. Os elementos traqueais são classificados como traqueídes, mostrando espessamento helical-escalariforme. Devido à desorganização e ao retorcimento, pode-se dizer que as traqueídes parasitas não estão perfeitamente conectadas umas às outras e ao restante do corpo. A zona de contato apresenta muita plasticidade. Descreve-se pela primeira vez a ampla gama de posicionamento de um extensor na interface parasita-hospedeiro. Geralmente, o parênquima do extensor está em contato com o parênquima hospedeiro. Imagens sucessivas demonstram que apenas algumas poucas traqueídes parasitas alcançam com êxito o vaso hospedeiro. Existem associações singulares entre traqueídes parasitas e vasos hospedeiros que levam às outras formas de contato. O extensor pode rotacionar e se posicionar lateralmente segundo o mesmo eixo do vaso hospedeiro. Além disso, elementos de vaso hospedeiros podem se deslocar em direção aos extensores, numa maneira de atração muito conspícua nunca antes documentada. O segundo capítulo se propõe a verificar a existência da continuidade simplástica entre parasita e hospedeiro e a ocupação do interior de células hospedeiras por células parasitas. Ambos os objetivos foram alvos de muitas controvérsias em estudos anteriores. A análise também se baseou em unir elementos constatados em Microscopia Óptica, Microscopia Confocal e Microscopia Eletrônica de Transmissão. O desenvolvimento do extensor provoca muitas lacunas nos tecidos hospedeiros, porém nem sempre as células parasitas ocupam tais espaços. Por outro lado, protoplastos de células isoladas, não pertencentes aos extensores, ocupam o lúmen de células hospedeiras. O início se dá nas células do raio (na porção junto ao câmbio) e depois são também invadidas células do xilema secundário. Não foram observados plasmodesmas secundários entre parasita e hospedeiro. Porém, a degeneração de parede celular hospedeira pode ocorrer bem ao lado de uma célula parasita. As células hospedeiras podem se desorganizar e deteriorar completamente ou acumular substâncias fenólicas. O terceiro capítulo aborda o impacto do parasitismo sobre o xilema secundário hospedeiro. Esse estudo se destaca como primeiro a focar as conseqüências do parasitismo de uma holoparasita sobre aspectos anatômicos do lenho (e não o floema hospedeiro). A partir de populações das três espécies foram obtidos caules parasitados e saudáveis, dos quais foram medidos: comprimento de elemento de vaso, comprimento de fibra, freqüência de vasos e diâmetro tangencial de vaso. Além disso, são apresentados dados sobre a altura, diâmetro basal e circunferência na base nos indivíduos da população de M. setosa. Os dados foram comparados com Teste T de Student lineares e correlações. O parasitismo influencia negativamente o tamanho (altura, diâmetro basal e circunferência na base), comprimento de elemento de vaso, comprimento de fibra e diâmetro tangencial de vaso. No entanto, lenhos parasitados têm maior freqüência de vasos. Os resultados apresentam modificações semelhantes àquelas observadas em lenhos de plantas sob estresse de poluição ou seca. A teoria da eficiênciasegurança pode ser aplicada na interpretação do parasitismo. O hospedeiro responde à parasita aumentando a segurança, mas mantendo a condutividade hidráulica total em seus níveis normais. / Pilostyles (Apodanthaceae) are endoparasitic angiosperms of Fabaceae stems and one of the most remarkable situations of body reduction. This study focuses the vegetative body of P. ulei. From an external view, there are only tiny flowers which break out the host periderm. Internally, they are connected to masses of vegetative body. These masses, formed by parenchyma (which have no storage function), occupy especially the phloem area of the Mimosoidea hosts. From them, groups of twisted tracheary elements surrounded by parenchyma cells - called sinkers - run into the host secondary xylem. Tracheary elements were interpreted as tracheids, with helicoidal to scalariform thickening. Due to their disorganised and twisted features, parasite tracheids could be considered not perfectly connected to each other and from the rest of the body. The contact zone shows wide morphological plasticity. Here is described, by the first time, the wide range of sinker positioning in the host-parasite interface. Usually, sinker parenchyma contacts host parenchyma. Successive images show that only a few parasite tracheids successfully reach the host vessel. There are unique associations between parasite tracheids and host vessels which lead to other forms of contact. Sinker can rotate and be laterally positioned to the host vessel. Moreover, host vessels elements can head for sinkers, in ways of a strong attraction never documented.¶ Pilostyles (Apodanthaceae) are endoparasitic angiosperms of Fabaceae stems. The vegetative body, the endophyte, consists of masses of parenchyma cells and sinkers. Sinker development causes gaps in host tissues. Parasite protoplast parenchyma, not associated with sinkers, can occupy host cell lumina. The entrance starts in host ray cells and spread to secondary xylem cells. Parasite and host cells do not form secondary plamodesmata. However, host wall degeneration can occur beside a parasite cell. Host cells also can be completely deteriorated or promote phenol compounds accumulation. Pilostyles (Apodanthaceae) are endoparasites of Fabaceae stems. The body structure consists of masses of parenchyma cells in the host phloem and groups of twisted tracheary elements surrounded by parenchyma cells - called sinkers - running into the host secondary xylem. This is the first study focusing the impact of the holoparasite Pilostyles parasitism on the host secondary xylem stem. From populations of Mimosa foliolosa, M. maguirei and M. setosa were obtained \"healthy\" and parasited stems by P. ulei. Measurements of vessel element lenght, fiber lenght, vessel diameter and vessel frequency were made on digital imaging. Height, basal diameter and basal circumference of stem in M. setosa population were also measured. The data were comparated by linear Student\'s Tests T and correlations. The parasitism performs a negative influence on size (height, basal diameter and circumference), vessel diameter, vessel element lenght and fiber lenght. On the other hand, parasited stems have the higher vessel frequency. The results show similar modifications on xylem architecture as observed on plants stressed by polution or drought. It seems that the theory of efficiency/safety can also be applied on the interpretation of parasitism, even considering that is a case of endoparasitism. The host responds to the parasite increasing the safety but keeping the total hydraulic conductivity at normal levels.¶
238

Efic?cia da associa??o de abamectina com fluazuron no controle de Rhipicephalus microplus, Dermatobia hominis e nemat?ides gastrointestinais em bovinos / Efficacy of abamectin with fluazuron association in control of Rhipicephalus microplus, Dermatobia hominis and gastrointestinal nematodes in cattle

Rocha, Cristiane Nunes Coelho da 21 March 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-10-16T12:11:58Z No. of bitstreams: 1 2016 - Cristiane Nunes Coelho da Rocha.pdf: 2134676 bytes, checksum: 7d111f5f6a4f012cde150c537673a52f (MD5) / Made available in DSpace on 2017-10-16T12:11:58Z (GMT). No. of bitstreams: 1 2016 - Cristiane Nunes Coelho da Rocha.pdf: 2134676 bytes, checksum: 7d111f5f6a4f012cde150c537673a52f (MD5) Previous issue date: 2016-03-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The purpose of the research was to evaluate the efficacy of association abamectin 0.6% with fluazuron 3.0% in control of Rhipicephalus microplus, Dermatobia hominis and gastrointestinal nematodes in cattle. For this, there were five tests in which the control group animals received no treatment, while animals in the treated group received the formulation within the association in a single dose of 600 mcg of abamectin and 3 mg of fluazuron per Kg of body weight by route ?pour-on?. As to acaricide efficacy, two tests were conducted, one using artificially infested cattle and other naturally infested by Rhipicephalus microplus. In the same manner, a test was conducted to evaluate the efficacy of the product in test front of Dermatobia hominis naturally infested cattle. And two tests anthelmintic efficacy in infected cattle naturally and artificially by gastrointestinal nematodes. The mean of the carrapaticide efficacy for cattle artificially infested with R. microplus over the 23 days after treatment was 87,40%. The preventive effectiveness results of 98,12%; 98,68%; 98,36%; 97,88%; 96,76%; 96,45%; 96,84%; 97,03%; 95,36% and 87,07% respectively for the experimental days +7, +14, +21, +28, +35, +42, +49, +56, +63, +70. The acaricide effectiveness for naturally infested cattle by R. microplus was 96,30%; 96,90%; 95,98%; 96,83%; 98,32%; 96,12%; 96,15%; 98,8%; 97,18%, 99,12%; 97,18%; 98,04% and 77,50%, respectively for the experimental days +7, +14, +21, +28, +35, +42, +49, +56, +63, +70, +77, +84 and +91 for the treated group. The efficacy of the test product to D. hominis was 90,70% and 96,84% for days +7 and +14. The values of anthelmintic efficacy in naturally infected cattle with gastrointestinal nematodes was 92,17%; 89,32%; 87,38% respectively for the experimental days +7, +14, +21 for the treated group. For cattle artificially infected by gastrointestinal nematodes the efficacy was 92,59%; 97,62%; 87,82%; 86,96%; 96,00% respectively for Haemonchus placei, Trichostrongylus axei, Cooperia punctata, Cooperia pectinata and Oesophagostomum radiatum. The association abamectin 0.6% with fluazuron 3.0% was effective in artificially infested cattle and naturally infested by R. microplus, as well as demonstrates efficacy for D. hominis. The test product showed efficacy also in the reduction the eggs counts per gram of feces (EPG) in cattle naturally infected with gastrointestinal nematodes, as well as shown to be effective front of artificial infections with H. placei, T. axei and O. radiatum and has presented moderately effective against C. pectinata and C. punctata / O objetivo da pesquisa foi avaliar a efic?cia da associa??o de abamectina 0.6% com fluazuron 3.0% controle de Rhipicephalus microplus, Dermatobia hominis e nemat?ides gastrointestinais em bovinos. Para isso, foram realizados cinco ensaios, nos quais os animais do grupo controle n?o receberam tratamento, enquanto que os animais do grupo tratado receberam a formula??o da associa??o na dose ?nica de 600 mcg de abamectina com 3 mg de fluazuron por Kg de peso corporal, por meio de via ?pour-on?. Quanto ? atividade carrapaticida, foram conduzidos dois ensaios, um utilizando bovinos artificialmente infestados e outro naturalmente infestados por Rhipicephalus microplus. Da mesma forma, foi realizado um ensaio para avaliar a efic?cia do produto em teste frente a Dermatobia hominis em bovinos infestados naturalmente e dois ensaios de efic?cia anti-helm?ntica em bovinos naturalmente e artificialmente infectados por nemat?ides gastrointestinais. A m?dia da efic?cia carrapaticida para bovinos artificialmente infestados por R. microplus ao longo dos 23 dias ap?s o tratamento foi de 87,40%. O resultado da efic?cia preventiva foi de 98,12%; 98,68%; 98,36%; 97,88%; 96,76%; 96,45%; 96,84%; 97,03%; 95,36%; e 87,07% respectivamente para os dias experimentais +7, +14, +21, +28, +35, +42, +49, +56, +63, +70. A efic?cia carrapaticida para bovinos naturalmente infestados por R. microplus foi de 96,30%; 96,90%; 95,98%; 96,83%; 98,32%; 96,12%; 96,15%; 98,8%; 97,18%, 99,12%; 97,18%; 98,04% e 77,50%, respectivamente para os dias experimentais +7, +14, +21, +28, +35, +42, +49, +56, +63, +70, +77, +84 e +91 para o grupo tratado. A efic?cia do produto em teste para D. hominis foi de 90,70% e 96,84%, para os dias +7 e +14. Os valores de efic?cia anti-helm?ntica em bovinos naturalmente infectados por nemat?ides gastrointestinais foi de 92,17%; 89,32%; 87,38% respectivamente para os dias experimentais +7, +14, +21 para o grupo tratado. Para bovinos artificialmente infectados por nemat?ides gastrointestinais, a efic?cia foi de 92,59%; 97,62%; 87,82%; 86,96%; 96,00% respectivamente para Haemonchus placei, Trichostrongylus axei, Cooperia punctata, Cooperia pectinata e Oesophagostomum radiatum. A associa??o de abamectina 0.6% com fluazuron 3.0% demonstrou ser eficaz em bovinos artificialmente e naturalmente infestados por R. microplus, assim como apresentou efic?cia para D. hominis. O produto em teste apresentou efic?cia tamb?m na redu??o de ovos por grama de fezes (OPG) em bovinos naturalmente infectados por nemat?ides gastrointestinais, assim como, demonstrou ser efetivo frente a infec??es artificiais por H. placei, T. axei e O. radiatum, e apresentou-se moderadamente efetivo frente a C. pectinata e C. punctata.
239

Reciprocal interactions between Leishmania and their microenvironments during infection in the sand fly gut and human macrophages

Kelly, Patrick Hogan 01 May 2017 (has links)
The Leishmania spp. are kinetoplastid protozoan parasites that cause a spectrum of highly prevalent and neglected tropical diseases known as leishmaniasis. The parasites must undergo two life forms during their life cycle: the extracellular promastigote life stage within the sand fly vector, and the intracellular amastigote life stage after internalization of host phagocytic cells. In the extracellular life stage, Leishmania promastigotes reside and develop to their infectious metacyclic form solely in the gut lumen of the sand fly, a process known as metacyclogenesis. During this process, other organisms that co-inhabit the sand fly gut, collectively known as the microbiome, influence parasite development. Based on the hypothesis that vector gut microbiota influence the development of parasite virulence, we sequenced midgut microbiomes of the sand fly Lutzomyia longipalpis with or without L. infantum infection. Sucrose fed sand flies contained a highly diverse, stable midgut microbiome. Blood feeding caused a decrease in bacterial richness, which eventually recovered. However, bacterial richness progressively decreased in L. infantum-infected sand flies. Furthermore, parasites altered the relative abundance of several bacterial phylogenies, including Pseudomonas and Serratia. Importantly, antibiotic-mediated perturbation of the midgut microbiome rendered sand flies unable to support parasite growth and consequent development to infectious metacyclic forms, and revealing the level of microbial diversity may induce flies resistant to infection. Together, these data suggest the sand fly midgut microbiome is a critical factor for Leishmania growth and differentiation prior to disease transmission. During the intracellular amastigote life form, macrophages are the primary cell type to phagocytize parasites. The effect of secreted factors such as exosomes from Leishmania-infected human cells and their effect on the immune response has not been extensively investigated. In this thesis, we characterized the proteome of primary human donor monocyte-derived macrophage (MDM) exosomes during L. infantum infection compared to donor-matched uninfected controls, and determined their impact on naïve MDMs measured by cytokine gene expression and resistance to subsequent parasite infection. Proteomic comparisons of infected and uninfected MDM exosomes were made using stable isotopic dimethyl labeling LC-MS/MS technology. A total of 484 human proteins were identified between four donors. Proteins significantly less abundant in exosomes derived from infected MDMs were matrix metalloprotease 9, galectin-3 binding protein, and several Annexins and histone proteins. Proteins more abundant included galectin-1, galectin-9, and serotransferrin and transferrin receptor 1. Interestingly, class I and class II MHC protein chains were differentially abundant in our samples. Furthermore, we observed several Leishmania spp. proteins in exosomes from infected MDMs as well. Naïve MDMs pretreated with exosomes from infected or uninfected MDM for 4 hours were not more resistant to L. infantum infection nor displayed increased gene expression of the pro-inflammatory cytokines IL-1α, IL-1β, IL-6, IL-8 or TNF-α. To date, the work presented in this thesis is the first to comprehensively identify the proteome in primary human MDM exosomes during Leishmania spp. infection, and to determine the impact of these exosomes on the immune response of other naïve human MDMs.
240

Trichinella pseudospiralis, Trichinella spiralis : a comparative study of biological and immunological parameters in mice.

Karmi, Tarif Osama. January 1981 (has links)
No description available.

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