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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.
71

Caracterização da biodiversidade dos mixozoários (Cnidaria:Myxosporea) parasitos de peixes do rio Batalha, médio rio Tietê, São Paulo

Tagliavini, Vinícius Panciera January 2018 (has links)
Orientador: Rodney Kozlowiski de Azevedo / Resumo: Os parasitos do filo Myxozoa são endoparasitas obrigatórios que infectam peixes, anfíbios, répteis, mamíferos, aves aquáticas em diversas regiões do mundo, com mais de 2180 espécies descritas, estando entre os mais importantes patógenos de peixes, porém, pouco se conhece deste parasito em peixes do Brasil. Neste estudo foram realizadas coletas entre março e setembro de 2016, na qual foram coletados 30 exemplares de curimba (Prochilodus lineatus) e dezessete exemplares de lambari (Astyanax altiaparanae), oriundos do rio Batalha, em dois locais de coleta, um ponto de coleta no município de Reginópolis e outro ponto no município de Agudos, estado de São Paulo. Foram utilizadas análises morfológicas (microscopia de luz, histologia e análise ultraestrutural), técnicas de biologia molecular (PCR e sequenciamento) na descrição de duas espécies de Henneguya Duas espécies foram documentadas neste estudo, uma delas foi encontrada infectando o filamento primário da brânquia de P. lineatus e é descrita neste estudo como Henneguya prochilodus e outra espécie encontrada infectando o filamento secundário da brânquia de A. altiparanae, a qual foi proposto uma descrição expandida da Henneguya chydadea Barassa et al. (2003), previamente descrita utilizando análises morfológicas e histopatologia. Análise filogenética do gene 18S rDNA foi realizada para avaliar a relação filogenética dessas duas espécies de Henneguya com outras espécies de mixosporídeos da América do Sul e de outras regiões do m... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Myxozoa parasites are obligate endoparasites that infect fish, amphibians, reptiles, mammals, waterfowl in several regions of the world, with more than 2180 described species, being among the most important fish pathogens, but little is known of this parasite in fish from Brazil. In this study were collected from March to September 2016, where 30 specimens of Curimba (Prochilodus lineatus) and seventeen specimens of lambari (Astyanax altiaparanae) from the Batalha River, in two collection sites, a collection point in the municipality of Reginópolis and another point in the municipality of Agudos, state of São Paulo. Morphological analyzes (light microscopy, histology and ultrastructural analysis), molecular biology techniques (PCR and sequencing) were used to describe two species of Henneguya. Two species were documented in this study, one of which was found infecting the primary filament of the gill of P. lineatus and is described in this study as Henneguya prochilodus and another species found infecting the secondary filament of the gill of A. altiparanae, which has been proposed an expanded description of Henneguya chydadea Barassa et al. (2003), previously described using morphological analysis and histopathology. Phylogenetic analysis of the 18S rDNA gene was performed to evaluate the phylogenetic relationship of these two species of Henneguya with other species of myxosporids from South America and other regions of the world. / Mestre
72

Étude anatomique macroscopique et ultrastructurale de la dure-mère au niveau de la région périsellaire / The interperiosteodural concept applied to the perisellar compartment : a microanatomical and electron microscopy study

François, Patrick 26 October 2009 (has links)
Les auteurs ont mené une étude anatomique à partir de 20 cadavres. Ce travail a permis d’étudier le concept inter-périostéo-dural appliqué à la région périsellaire en combinant une étude anatomique microscopique et une étude en microscopie électronique des feuillets de la dure-mère. Celle-ci est constituée de deux feuillets : un feuillet ostéo périosté, adhérent à l’os et un feuillet encéphalique au contact du cerveau. Ces deux feuillets sont accolés l’un à l’autre au niveau de la fosse cérébrale moyenne et sont séparés l’un de l’autre au niveau de l’orbite, de la loge caverneuse ou de l’espace épidural rachidien pour former le concept inter périostéo dural. Les feuillets ostéo-périosté et encéphalique ne partagent pas le même aspect en microscopie à balayage au niveau des surfaces. Cette différence d’aspect s’explique par l’histologie des méninges, notamment la nature de l’interface arachnoïde-dure mère. Ces résultats sont importants et démontrent pour la première fois, à un échelon microscopique, la véracité du concept inter-périostéo-dural. Les angiolipomes sont des tumeurs rares du système nerveux central et se développent essentiellement dans l’orbite, la loge caverneuse et l’espace épidural rachidien. À partir d’une analyse de la littérature et d’un travail anatomique spécifique, axé sur la graisse caverneuse, nous suggérons que l’angiolipome soit la tumeur emblématique du concept inter périostéo-dural. / The authors studied the cadaveric heads obtained from 20 adults. We studied by microscopic and ultrastructural methods the extra dural neural axis compartment applied to the perisellar compartment. The dura mater had two dural layers : the endosteal layer, which was firmly attached to the bone and the meningeal layer, which directly covered the brain. These layers joined together in the middle temporal fossa and separated in the orbital, lateral sellar compartment or epidural space to form the extra dural neural axis compartment. The endosteal layer and meningeal layer were not identical on electron microscopy; this result can be readily related to the histology of the meninges. These findings demonstrated the existence of the extra dural neural axis compartment, a notion which has generally been accepted but never demonstrated microscopically. Angiolipomas are rare tumors of the central nervous system which most frequently develop in the orbit, the cavernous space and the epidural space of the spine. Using data from the published litterature and an experimental anatomic approach, we demonstrated that the cavernous space contains adipose tissue. Consequently, we suggested that angiolipomas constitute the emblematic tumor of the interperiostal dural concept
73

A morphometric analysis of ultrastructural dynamics in the murine glomerulus following surgically-induced renal hypertension

Stevenson, James Ware 20 June 2016 (has links)
Chronic kidney disease (CKD) and end stage renal disease (ESRD) are significant causes of adult morbidity and mortality worldwide. Though these conditions are common, the mechanisms of pathogenesis in kidney disease are poorly understood. Genetic predisposition has been established in the African American population; however this does not explain the ubiquity of CKD in the United States and abroad. Diabetes and hypertension are the two most frequently occurring co-morbidities in kidney disease and both have been identified as putative sources of injury to the delicate filtering structures of the kidney. Furthermore, the intrinsic functional relationship between the cardiovascular and renal organ systems adds to the plausibility of a hemodynamic cause. In light of this knowledge, we aim to explore the roles of genetic predisposition and hypertension in the pathogenesis and progression of CKD. The filtering apparatus of the kidney, the glomerulus, is a looping tuft of capillaries specialized to allow the passage of water and certain substances from the blood while restricting others. Glomeruli at the corticomedullary boundary of the kidney experience blood pressures closer to those in systemic arterioles and are subject to similar hemodynamic stresses. To evaluate the role of hypertension in CKD, we employed a well-known model of hypertensive kidney disease in mice involving uninephrectomy (UNX), subcutaneous implantation of a timed-release pellet containing the active aldosterone precursor deoxycorticosterone acetate (DOCA), and a high-salt diet. Given the role of heritability in human CKD pathogenesis, we applied the DOCA-UNX model in two strains of mice with differing susceptibility to kidney damage, the 129S6 and C57BL/6 strains, to evaluate the effects of genetic predisposition. Mice were subjected to varying lengths of hypertension exposure and their kidneys were subsequently examined by transmission electron microscopy (TEM). Ultrastructural lesions of glomeruli were evaluated by a renal pathologist and assigned subjective pathology scores based on the extent and severity of involvement. We hypothesized that certain glomerular lesions, particularly those involving the podocytes of the visceral epithelium, would increase in severity in mice with heritable susceptibility (129S6) as well as those with longer exposure to glomerular hypertension. Our observations demonstrate these hypotheses are partially correct. By TEM histopathology, mouse strain was found to have a significant effect on the severity of certain epithelial lesions while duration of hypertension had a significant effect on the overall morphological pathology of the podocytes, glomerular basement membrane, and glomerulus as a whole. These results provide a promising foundation for further investigation of the pathogenesis of CKD in mice.
74

Avaliação do efeito do derivado de β-lapachona R72 em formas tripomastigotas de Trypanosoma cruzi e na infecção de macrófagos pelo T. cruzi in vitro

Anjos, Danielle Oliveira dos January 2014 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2015-06-16T14:16:03Z No. of bitstreams: 1 Daniele Oliveira dos Anjos. Avaliação... 2014.pdf: 3009181 bytes, checksum: 49f7e0a87a33c50bdde2fa65c23f8c9f (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2015-06-16T14:16:12Z (GMT) No. of bitstreams: 1 Daniele Oliveira dos Anjos. Avaliação... 2014.pdf: 3009181 bytes, checksum: 49f7e0a87a33c50bdde2fa65c23f8c9f (MD5) / Made available in DSpace on 2015-06-16T14:16:12Z (GMT). No. of bitstreams: 1 Daniele Oliveira dos Anjos. Avaliação... 2014.pdf: 3009181 bytes, checksum: 49f7e0a87a33c50bdde2fa65c23f8c9f (MD5) Previous issue date: 2014 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / A tripanossomíase americana também conhecida como doença de Chagas é um importante problema de saúde pública, uma doença de origem parasitária que afeta 8 milhões de pessoas na América Latina (OMS, 2013). Atualmente existem apenas dois fármacos utilizados na prática clínica: o benzonidazol e o nifurtimox. Esse último não é usado no Brasil. Esses fármacos apresentam efeitos colaterais e são confrontados com cepas resistentes (FILARDI e BRENER, 1987; MEJIA et al., 2012). Desta forma, torna-se necessária a busca de compostos que apresentem maior eficácia e menor toxicidade. No presente trabalho foi avaliado o efeito do composto derivado de β–lapachona, R72, em formas tripomastigotas de T. cruzi e em macrófagos infectados in vitro. Observamos que a R72 reduziu, significativamente (p<0,05), o número de parasitos viáveis, produzindo IC50 de 15 μM. A análise ultraestrutural revelou que a R72 causou danos na bolsa flagelar, cinetoplasto e mitocôndrias. Além disso, encontramos a presença de corpúsculos lipídicos e figuras de mielina no citoplasma do protozoário, indicando processos de autofagia, a qual foi confirmada pela sonda MDC. A análise por citometria de fluxo indicou morte por apoptose, necrose e produção de espécies reativas de oxigênio. Além disso, o composto não apresentou toxicidade para células de mamíferos em concentrações inferiores a 200 μM. A R72 reduziu, significativamente, a percentagem de macrófagos infectados pelo T. cruzi e o número de parasitos por macrófagos. Verificamos inibição da internalização de parasitos quando os macrófagos foram tratados previamente com o composto R72. Análise ultra-estrutural evidenciou um processo de autofagia caracterizado pela presença de vacúolo autofágico e formação de corpúsculos lipídicos. O mecanismo envolvido na formação de vacúolos autofágicos e corpúsculos lipídicos é independente da produção de óxido nítrico. Esses resultados ajudam a elucidar os mecanismos de ação de fármacos potenciais para a quimioterapia da doença de Chagas. / The American trypanosomiasis also known as Chagas disease is a major public health problem, a parasitic disease caused that affects 8 million people in Latin America (OMS, 2013). Currently there are only two drugs used in clinical practice: the benznidazole and the nifurtimox. The latter is not used in Brazil. These drugs are faced with considerable side effects and resistant strains (FILARDI e BRENER, 1987; MEJIA et al., 2012). Thus the search for drugs effective in the chronic phase of the disease and lower toxicity is required. In this study the effect of the β-lapachone derivative R72 in trypomastigote forms of T. cruzi and upon the infection of macrophage by T. cruzi in vitro. We observed that the R72 significantly inhibited (p<0,05) the number of viable parasites, producing IC50 of 15 μM. The ultrastructural analysis by transmission electron microscopy revealed that the R72 has caused damage to the flagellar pocket, kinetoplast and mitochondria. Furthermore, we found the presence of lipid bodies and myelin figures in the cytoplasm of the protozoan indicating autophagic process, which was confirmed by the MDC probe. Analysis by flow cytometry indicated death by apoptosis and necrosis and production of reactive of reactive oxygen species. Furthermore, the compound did not show toxicity to mammalian cells at concentrations below 200 μM. The R72 significantly reduced the percentage of infected macrophages and the number of number of T. cruzi parasites per macrophage. We observed inhibition of internalization of parasites when macrophage were pretreated with the compound R72. Ultrastructural analysis revealed a process of autophagy characterized by the presence of autophagic vacuoles and lipid body formation. The mechanism involved in the formation of autophagic vacuoles and lipid body is independent of nitric oxide. These results help elucidating the mechanisms action of potential drugs and provide new tools for chemotherapy of Chagas disease.
75

Biologia reprodutiva de Corecoris fuscus, Leptoglossus gonagra, L. zonatus e Sphictyrtus fasciatus (Heteroptera: Coreidae), com ênfase aos aspectos ultraestruturais / Reproductive biology Corecoris fuscus, gonagra Leptoglossus, L. zonatus and Sphictyrtus fasciatus (Heteroptera: Coreidae), with emphasis on the ultrastructural aspects

Souza, Emi Rosane Silistino de [SOUZA] 07 March 2016 (has links)
Submitted by Emi Rosane Silistino de Souza null (emi.rosane@hotmail.com) on 2016-03-10T05:51:12Z No. of bitstreams: 1 DISSERTAÇÃO EMI 2016 OK.pdf: 3134204 bytes, checksum: c2496577f07709557fe6c8ab1c101ffb (MD5) / Approved for entry into archive by Sandra Manzano de Almeida (smanzano@marilia.unesp.br) on 2016-03-10T18:53:23Z (GMT) No. of bitstreams: 1 souza_ers_me_sjrp.pdf: 3134204 bytes, checksum: c2496577f07709557fe6c8ab1c101ffb (MD5) / Made available in DSpace on 2016-03-10T18:53:23Z (GMT). No. of bitstreams: 1 souza_ers_me_sjrp.pdf: 3134204 bytes, checksum: c2496577f07709557fe6c8ab1c101ffb (MD5) Previous issue date: 2016-03-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A Subordem Heteroptera contém cerca de 75 famílias, incluindo Coreidae, na qual pertencem as espécies Corecoris fuscus, Leptoglossus gonagra, L. zonatus e Sphictyrtus fasciatus, analisadas no presente trabalho. Os indivíduos dessa família são conhecidos por serem exclusivamente fitófagos e alimentam-se de plantas de valor comercial. Apesar da grande diversidade desta subordem, há poucos estudos relacionados com a ultraestrutura da espermátide dessas espécies. Assim, nesse trabalho, por meio da microscopia eletrônica de transmissão, foi analisado o desenvolvimento da espermiogênese na cabeça e no flagelo, com ênfase na formação do acrossomo, do adjunto do centríolo e dos derivados mitocondriais. O acrossomo tem origem a partir do complexo de Golgi, por meio da formação de uma vesícula pró-acrossomal e concomitante a esse processo é formado o adjunto do centríolo. O acrossomo determina o polo anterior do espermatozoide e o adjunto do centríolo determina o polo posterior. Observou-se também que no início do processo espermiogênico, as mitocôndrias encontram-se espalhadas no citoplasma, então gradualmente se fundem e dão origem ao complexo mitocondrial, o qual se divide, posteriormente, em duas subestruturas, denominadas derivados mitocondriais. Essas se posicionam bilateralmente ao axonema, o qual possui o padrão típico de disposição dos microtúbulos de 9 + 9 + 2. O processo de formação do acrossomo e dos derivados e a conformação dos microtúbulos do axonema são típicos de insetos. Além do padrão de microtúbulos do axonema, foram encontradas características sinapomórficas de Heteroptera, como a presença de duas estruturas paracristalinas em cada derivado mitocondrial e a presença de pontes que ligam os derivados mitocondriais ao microtúbulos axonemais, os quais são ferramentas importantes para auxiliar análises filogenéticas e taxonômicas. / The suborder Heteroptera contains about 75 families, including Coreidae, to which the species Corecoris fuscus, Leptoglossus gonagra, L. zonatus and Sphictyrtus fasciatus belong. Individuals of this family are known for being exclusively phytophagous and feeding on commercially valuable plants. Despite this suborder great diversity, there are only few studies on the ultrastructure of these species spermatid. Thus, in this study, through transmission electron microscopy, we analyzed the development of spermiogenesis in the head and the flagellum of C. fuscus, L. gonagra, L. zonatus and S. fasciatus, with emphasis on the formation of the acrosome, of the centriole adjunct and on development of mitochondrial derivatives. The acrosome originates from the Golgi complex through the formation of a pro-acrosomal vesicle and concomitant to this process, is formed the centriole adjunct. The acrosome determines the anterior pole of the sperm and the centriole adjunct determines the posterior pole. It was also observed that at the beginning of the spermiogenic process, the mitochondria are scattered within the cytoplasm, then gradually fusing and originating the mitochondrial complex, which is subsequently divided into two substructures, called mitochondrial derivatives. They are positioned bilaterally to the axoneme, having the typical pattern arrangement of the microtubule, which is 9 + 9 + 2. The process of acrosomes and derivatives formation and the conformation of axoneme’s microtubules are typical of insects. Besides the pattern of axoneme’s microtubules, synapomorphic features of Heteroptera were found, as the presence of two paracrystalline structures in each mitochondrial derivative and the presence of bridges connecting derivatives mitochondrial to the axonemal microtubules, which are important tools to assist in phylogenetic and taxonomic analyzes. / FAPESP: 2013/19864-5
76

Comparative morphology and phylogeny of anomalodesmatan bivalves

Sartori, André Fernando January 2010 (has links)
Anomalodesmatans comprise a large, ancient and ecologically diverse group of marine bivalves, but are nonetheless inconspicuous in most extant shallow water communities. For various reasons, which include their present scarcity and a bewildering array of disparate morphologies, representatives of the group have always proved difficult to interpret, and their systematics lagged behind those of most other major bivalve taxa. Most of this dissertation reports the results of a comparative investigation on the shell morphology and anatomy of extant anomalodesmatans, which formed the basis for a reassessment of hypotheses of primary homology established by previous investigators and identification of novel characters for phylogenetic inference. Due to the chief role played by the hinge ligament in authoritative discussions of anomalodesmatan evolution, this organ was chosen as the focus of a more detailed treatment. Discontinuous ontogeny of fibrous ligament is shown to characterise several members of the group, with the implication that, in contrast to the prevailing model,not all anomalodesmatan adult ligaments may be considered homologous. Likewise, a system of multicellular glands concerned with sediment agglutination was studied with particular emphasis because it is both exclusive to and widespread within Anomalodesmata. Evidence of preserved glandular secretion is recorded for the first time in fossil material and the glands themselves found in extant laternulids and pholadomyids, thus considerably expanding their known taxonomic distribution. Finally, this volume also documents the largest cladistic analysis of extant anomalodesmatans performed to date, including morphological data compiled from both original observations and literature accounts. Among traditionally recognised superfamilies, Pholadomyoidea, Clavagelloidea and Septibranchia were found monophyletic. Taxa commonly referred to Pandoroidea and Thracioidea were recovered as part of two new clades, which are also supported by recent molecular studies. Interpreted in the light of the fossil record, reconstructed phylogenetic relationships favour the iterative evolution of shallow infaunal and epifaunal anomalodesmatans from deep-burrowing ancestors over previously advanced patterns for the history of the clade, namely ventral migration of the ligament and irreversible radiations into a deep infaunal life habit.
77

Caracterização da biodiversidade dos mixozoários (Cnidaria:Myxosporea) parasitos de peixes do rio Batalha, médio rio Tietê, São Paulo / Characterization of the biodiversity of the mixozoaria (Cnidaria: Myxosporea) fish parasites of the Batalha river, the middle Tietê river, São Paulo / Caracterización de la biodiversidad de los mixozoarios (Cnidaria: Myxosporea) parásitos de peces del río Batalha, medio río Tietê, São Paulo

Tagliavini, Vinícius Panciera 21 February 2018 (has links)
Submitted by Vinicius Panciera Tagliavini (viniciustagliavini@gmail.com) on 2018-04-21T17:38:50Z No. of bitstreams: 1 Dissertação Vinícius Panciera Tagliavini.pdf: 3064208 bytes, checksum: 4c9144ee7408032982fc3216adac6c5a (MD5) / Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2018-04-23T17:37:37Z (GMT) No. of bitstreams: 1 tagliavini_vp_me_bot.pdf: 3064208 bytes, checksum: 4c9144ee7408032982fc3216adac6c5a (MD5) / Made available in DSpace on 2018-04-23T17:37:37Z (GMT). No. of bitstreams: 1 tagliavini_vp_me_bot.pdf: 3064208 bytes, checksum: 4c9144ee7408032982fc3216adac6c5a (MD5) Previous issue date: 2018-02-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os parasitos do filo Myxozoa são endoparasitas obrigatórios que infectam peixes, anfíbios, répteis, mamíferos, aves aquáticas em diversas regiões do mundo, com mais de 2180 espécies descritas, estando entre os mais importantes patógenos de peixes, porém, pouco se conhece deste parasito em peixes do Brasil. Neste estudo foram realizadas coletas entre março e setembro de 2016, na qual foram coletados 30 exemplares de curimba (Prochilodus lineatus) e dezessete exemplares de lambari (Astyanax altiaparanae), oriundos do rio Batalha, em dois locais de coleta, um ponto de coleta no município de Reginópolis e outro ponto no município de Agudos, estado de São Paulo. Foram utilizadas análises morfológicas (microscopia de luz, histologia e análise ultraestrutural), técnicas de biologia molecular (PCR e sequenciamento) na descrição de duas espécies de Henneguya Duas espécies foram documentadas neste estudo, uma delas foi encontrada infectando o filamento primário da brânquia de P. lineatus e é descrita neste estudo como Henneguya prochilodus e outra espécie encontrada infectando o filamento secundário da brânquia de A. altiparanae, a qual foi proposto uma descrição expandida da Henneguya chydadea Barassa et al. (2003), previamente descrita utilizando análises morfológicas e histopatologia. Análise filogenética do gene 18S rDNA foi realizada para avaliar a relação filogenética dessas duas espécies de Henneguya com outras espécies de mixosporídeos da América do Sul e de outras regiões do mundo. / The Myxozoa parasites are obligate endoparasites that infect fish, amphibians, reptiles, mammals, waterfowl in several regions of the world, with more than 2180 described species, being among the most important fish pathogens, but little is known of this parasite in fish from Brazil. In this study were collected from March to September 2016, where 30 specimens of Curimba (Prochilodus lineatus) and seventeen specimens of lambari (Astyanax altiaparanae) from the Batalha River, in two collection sites, a collection point in the municipality of Reginópolis and another point in the municipality of Agudos, state of São Paulo. Morphological analyzes (light microscopy, histology and ultrastructural analysis), molecular biology techniques (PCR and sequencing) were used to describe two species of Henneguya. Two species were documented in this study, one of which was found infecting the primary filament of the gill of P. lineatus and is described in this study as Henneguya prochilodus and another species found infecting the secondary filament of the gill of A. altiparanae, which has been proposed an expanded description of Henneguya chydadea Barassa et al. (2003), previously described using morphological analysis and histopathology. Phylogenetic analysis of the 18S rDNA gene was performed to evaluate the phylogenetic relationship of these two species of Henneguya with other species of myxosporids from South America and other regions of the world. / Capes: 20400004
78

Avaliação da capacidade de renovação do epitélio do mesêntero e seus efeitos no potencial reprodutivo de fêmeas adultas de Ceraeochrysa claveri (Neuroptera Chrysopidae) alimentadas durante a fase larval com óleo de nim (azadirachta indica A. JUSS) /

Scudeler, Elton Luiz. January 2016 (has links)
Orientador: Daniela Carvalho dos Santos / Resumo: Devido ao uso indiscriminado de inseticidas de largo espectro na produção agrícola e a vulnerabilidade dos inimigos naturais a este tipo de exposição, efeitos colaterais podem afetar a função biológica destes inimigos, tornando sua utilização no controle biológico impraticáveis. A busca por pesticidas mais seletivos sobre esses organismos benéficos é necessária, e entre as alternativas, enfatizamos o aumento do uso dos biopesticidas. Um dos biopesticidas amplamente utilizados é o óleo de nim (Azadirachta indica), e sua segurança e compatibilidade com os inimigos naturais têm sido mais esclarecidos através de estudos ecotoxicológicos que verificam os efeitos da exposição indireta através da ingestão de presas contaminadas. Assim, este estudo analisou a resposta das células epiteliais do mesêntero de adultos do crisopídeo Ceraeochrysa claveri quando expostos por ingestão de presa contaminada com óleo de nim durante a fase larval e a ocorrência de efeitos letais e subletais em seu desenvolvimento. Larvas de C. claveri foram alimentadas com ovos de Diatraea saccharalis tratados com óleo de nim nas concentrações de 0,5%, 1% e 2% durante todo período larval. Fêmeas adultas obtidas a partir destes tratamentos foram utilizadas em análises morfológicas e ultraestruturais da resposta celular do mesêntero. Além disso, parâmetros biológicos também foram avaliados durante o desenvolvimento pós-embrionário. O óleo de nim provoca efeitos citotóxicos no mesêntero através de pronunciadas alte... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Due to the indiscriminate use of broad-spectrum insecticides in agricultural production and the vulnerability of natural enemies to this type of pesticide exposure, side effects can affect the biological function of these enemies, making their use for biological control unfeasible. A search for more selective pesticides on these beneficial organisms is necessary, and among the alternatives, we emphasize the increased use of biopesticides. One of the biopesticides widely used is the neem oil (Azadirachta indica), and its safety and compatibility with natural enemies have been more clarified through ecotoxicological studies which check the effects of indirect exposure by intake of poisoned preys. Thus, this study analyzed the response of midgut epithelial cells of adult of lacewing Ceraeochrysa claveri when exposed by intake of contaminated prey with neem oil during the larval stage and the occurrence of lethal and sublethal effects on its development. Larvae of C. claveri were fed on eggs of Diatraea saccharalis treated with neem oil at a concentration of 0.5%, 1% and 2% throughout the larval stage. Adults female obtained from these treatments were used in the morphological and ultrastructural analyses of cellular response of midgut. Moreover, biological parameters were also measured during the post embryonic development. Neem oil causes cytotoxic effects on the midgut through pronounced alterations as cell swollen, loss of integrity of cell cortex, dilated cisternae of the ro... (Complete abstract click electronic access below) / Doutor
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Morfologia dos espermatozoides de Melittobia hawaiiensis, Perkins, M. australica, Girault (Chalcidoidea: Eulophidae) e Neochrysis lecointei, Ducke (Chrysidoidea: Chrysididea), com considerações filogeneticas em apocrita (Hymenoptera) / Spermatozoa morphology of Melittobia hawaiiensis, Perkins, M. australica, Girault (Chalcidoidea: Eulophidae) and Neochrysis lecointei, Ducke (Chrysidoidea: Chrysididea), with phylogenetic considerations in Apocrita (Hymenoptera)

Brito, Pedro Vale de Azevedo, 1982- 15 February 2008 (has links)
Orientadores: Mary Anne Heidi Dolder, Jose Lino Neto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T15:36:52Z (GMT). No. of bitstreams: 1 Brito_PedroValedeAzevedo_M.pdf: 5058045 bytes, checksum: a8e944c3ea7b5a920db9f092ea469fc2 (MD5) Previous issue date: 2008 / Resumo: Hymenoptera é uma das maiores ordens de inseto no mundo e nenhum outro grupo possui tantas espécies benéficas para o homem quanto esse. A morfologia dos espermatozóides tem provado ser capaz de fornecer dados úteis para estudos filogenéticos em diversos grupos de insetos, inclusive os Hymenoptera. Porém, os estudos existentes até o momento descrevendo a morfologia dos espermatozóides nessa ordem ainda não são suficientes para permitir inferências filogenéticas mais abrangentes. Neste trabalho descrevemos a morfologia dos espermatozóides de Melittobia hawaiiensis e M. australica (Chalcidoidea) e de Neochrysis lecointei (Chrysidoidea) resultando em dois manuscritos que estão em fase de submissão. Comparando os dados desse estudo com os disponíveis na literatura observamos que algumas características como a presença de estruturas espiraladas nos espermatozóides, presença de material extracelular associado ao ápice dos espermatozóides e a ordem de desorganização dos microtúbulos do axonema no final do flagelo, parecem fornecer informações possíveis de serem utilizadas na filogenia das superfamílias de Hymenoptera. Outras características, como a morfologia do adjunto do centríolo e dos derivados mitocôndrias, parecem ser capazes de fornecer informações que indicam as relações de parentesco entre táxons inferiores, inclusive gêneros (ou tribos) da mesma família / Abstract: Hymenoptera is one of the largest insect orders in the world and no other group presents so many benefic species for humanity. In spite of these insects¿ importance, there are still many uncertainties about this group¿s phylogeny. Spermatozoa morphology has proved useful in resolving phylogenetic questions in many insects¿ orders, including Hymenoptera, although the available studies describing sperm morphology in this order do not include enough taxa to allow detailed phylogenetic studies. This study describes the sperm morphology of Melittobia hawaiiensis and M. australica (Chalcidoidea) and of Neochrysis lecointei (Chrysidoidea), which resulted in two manuscripts to be submitted for publication. Comparing data obtained in this study with those available in the literature there are some characteristics such as the presence of spiraling structures in spermatozoa, the extracellular material coating spermatozoa apex and the order of disorganization of the axoneme microtubules at the flagellum end that could be used to provide information about the Hymenoptera superfamilies¿ phylogeny. Other characteristics, such as the centriolar adjunct and mitochondrial derivatives¿ morphology, provide information about the relationships among inferior taxons, including those of the same genera, or tribes of the same family / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural
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Ultraestrutura e expressão das enzimas: citocromo P450 aromatase e citocromo P450c17 (17-&#945;-hidroxilase/17,20-liase) nas diferentes fases do desenvolvimento da via espermática e espermatogênese em cutia (Dasyprocta sp.) criada em cativeiro / Ultrastructure and expression of enzymes: cytochrome P450 aromatase and cytochrome P450c17 (17-&#945;-hydroxylase/17,20-lyase) in different developmental stages of spermatogenesis and excurrent canals in agouti (Dasyprocta sp.) kept in captivity

Maria Angélica Machado Arroyo 05 July 2013 (has links)
Espécies silvestres com grande potencial zootécnico devem ser exploradas de forma racional a fim de se evitar a extinção das mesmas. Assim se dá a importância de pesquisas voltadas à reprodução daquelas criadas em cativeiro, como a cutia (Dasyprocta sp.). Este animal é um mamífero e roedor vivente, em sua maioria, na Caatinga brasileira. A ultraestrutura é a base para determinar os estágios celulares e, assim, facilitar as comparações dos processos entre cutias e roedores silvestres ou outros mamíferos. As enzimas P450 aromatase e P450c17 são responsáveis pela regulagem da produção de estrógenos e andrógenos, respectivamente. Considerando a hipótese de que o comportamento de expressão das enzimas do complexo citocromo P540 permanece o mesmo no testículo e na via espermática de cutias durante as fases de desenvolvimento sexual, objetivou-se observar a atuação das enzimas P450 aromatase e P450c17 (17-&#945;-hidroxilase/17,20-liase) nas diferentes fases do desenvolvimento sexual, detalhar a ultraestrutura dos componentes desta via e constatar o desenvolvimento do processo espermatogênico. Segmentos do ducto deferente, epidídimo e testículo de 28 cutias machos em diferentes idades (um dia, 2-14 meses) foram fixados em paraformoldeído e glutaraldeído. O material foi coletado no Centro de Multiplicação da Universidade Federal Rural do Semiárido, Mossoró, RN (Autorização IBAMA nº 2028236/2008). Foram feitos: histologia, seguindo o protocolo padrão para hematoxilina e eosina; processamento para corte semifino (azul de toluidina); microscopia eletrônica de transmissão e varredura; e imunohistoquímica. Este trabalho foi pioneiro ao observar que o epidídimo de cutias é composto por células basais, células principais, células haloides e, quando impúbere, por células \"limpas\", e por células apicais, quando a partir da puberdade. O ducto deferente de cutias antes da puberdade era caracterizado por duas camadas musculares, possivelmente devido à falta de trânsito espermático. No epitélio germinativo foram encontradas, em sua maioria, células em prófase I, principalmente em paquíteno. A espermiogênese é completa quando na pré-puberdade, entretanto, a espermiação ocorre a partir dos 9 meses de idade. A expressão da enzima P450 aromatase variou ao longo do desenvolvimento sexual, sendo na puberdade seu pico de atividade. A P450c17 não mostrou nenhuma ação em qualquer fase sexual. Pode-se concluir que o epitélio germinativo testicular e intersticial, bem como o epitélio pseudoestratificado estereociliado do epidídimo e do ducto deferente de cutias criadas em cativeiro sofrem mudanças morfológicas e funcionais ao longo do desenvolvimento sexual. As atividades androgênicas preponderantes em cutias criadas em cativeiro ocorrem no período da puberdade. / Wild species with great potential livestock should be explored rationally in order to prevent the extinction of the same. Thus is the importance of research aimed at reproducing those bred in captivity, such as agouti (Dasyprocta sp.). This animal is a mammal and rodent living mostly in the Brazilian Caatinga. The ultrastructure is the basis for determining the stages and thus facilitates comparisons of cases between agouti and wild rodents or other mammals. The enzymes P450 aromatase and P450c17 are responsible for regulating the production of estrogens and androgens, respectively. On the assumption that the behavior of expression of the enzymes of complex cytochrome P540 remains the same in the testis and excurrent canals of the agouti during the stages of sexual development, aimed to observe the activity of the enzymes P450 aromatase and P450c17 (17-&#945;- hidroxilase/17,20-lyase) in different stages of sexual development, detail the ultrastructure of the components of this pathway and observe the development of spermatogenesis. Segments of the vas deferens, epididymis and testis of 28 agouti males at different ages (1 day, 2-14 months) were fixed in glutaraldehyde and paraformoldehyde. The material was collected on Center of Multiplication of Federal Rural University of the Semi-arid, Natal, RN (IBAMA Authorization No. 2028236/2008). Were made: histology following the standard protocol for hematoxylin and eosin; processing to semithin (blue toluidine), electron microscopy of transmission and scanning; and immunohistochemistry. This work was pioneered by observing that the epididymis is composed by basal cells, principal cells, haloids cells; and for clean cells when impubertal and apical cells after puberty in agoutis. The vas deferens before puberty was characterized by two muscle layers, possibly due to the lack of sperm transit. In the germinal epithelium were found mostly cells in prophase I, mainly in pachytene. Spermiogenesis is complete when prepubertal phase; however, spermiation takes place from 9 months of age. The expression of enzymes of the cytochrome complex varied over sexual development and peak activity of P450 aromatase was at puberty. The P450c17 showed no action at any stage of sexual development. It can be concluded that the testicular germinal epithelium and interstitial epithelium as well as the pseudostratified estereociliated epithelium of the epididymis and vas deferens undergo morphological and functional changes during the sexual development. Androgenic activities prevalent in agoutis kept in captivity occur during puberty.

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