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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.
181

Emprego do Hamster sírio (Mesocricetus auratus) como modelo biológico para a indução de portador renal de leptospiras / The use of sirius hamster (Mesocricetus Auratus) as a biological model for inducing kidney carrier of leptospirosis

Milton Kolber 02 March 2006 (has links)
O emprego do hamsters (Mesocricetus auratus) como modelo biológico experimental para a reprodução da condição de portador renal de leptospiras foi investigado em machos e fêmeas jovens com 80 a 120 g de peso vivo. Os animais foram experimentalmente infectados com estirpe patogênica do sorovar Pomona caracterizada por provocar a morte por leptospirose entre o quinto e o décimo dia pós-infecção. No segundo dia pós-infecção os animais foram tratados com estolato de eritromicina, nas concentrações de 10, 20, 40 e 80 mg/kg de peso vivo. Aos 30 dias, da infecção experimental os sobreviventes foram anestesiados com isofluorano e procedeu-se a colheita de sangue para a determinação dos indicadores da função hepática e renal (Proteínas totais, Albumina, Uréia, Creatinina, Fosfatase Alcalina, Alanina Aminotransferase, Aspartato Aminotransferase, Bilirrubinas Indireta, Bilirrubinas Direta e Bilirrubinas Totais), bem como o titulo de aglutininas pela prova de soro aglutinação microscópica. A seguir, com o aprofundamento da anestesia, os animais foram submetidos a eutanásia e necropsiados para a colheita de tecido renal e hepático destinados aos exames histopatológicos pelas colorações de Hematoxilina - Eosina e Warthin- Starry, bem como do isolamento de leptospiras por cultivo em meio de Fletcher. Houve controles do inóculo infeccioso, do tratamento com antibiótico e do sistema de manejo adotado. O número de DL 50 efetivamente empregadas no inóculo infeccioso foi de 7,11. No grupo controle do antibiótico foi constatado elevação do nível de fosfatase alcalina e degeneração vacuolares dos hepatócitos para as concentrações de 40 a 80 mg de antibiótico. Os portadores renais de leptospira foram obtidos entre os animais tratados com 40 ou 80 mg de estolato de eritromicina, independentemente do sexo; estes animais apresentaram elevação dos níveis séricos de creatinina e proteínas totais já as determinações de albumina, uréia, alanina aminotrasferase, aspartato aminotransferase, bilirrubinas direta, bilirrubinas indiretas e totais foram iguais as encontradas em animais não infectados por leptospiras e não tratados com antibióticos. As alterações histológicas encontradas nos animais portadores de leptospiras foram degeneração vacuolar em hepatócitos, sangue no espaço porta, congestão glomerular. Nos animais induzidos a condição de portadores renais de leptospiras os títulos de anticorpos aglutinantes, para o sorovar homólogo ao da infecção, expressos em logaritmo de base, 10 foram iguais ou superiores a 1,19. / The use of hamsters (Mesocricetus auratus) as experimental model for the reproduction of leptospires kidney carrier condition was investigated on youngs males and females with 80 to 120 g of living weight. The animals were experimentally infected with pathogenic strain of serovar Pomona able of causing the death by leptospirosis between the fifth and the tenth post-infection day. On the second day post-infection the animals were treated with erythromycin estolate at the concentrations of 10, 20, 40 and 80 mg/ kg of living weight. At the 30th day of experimental infection the survivors were anesthetized with isoflurane and blood sample were collected for the determination of kidney and liver functions (Total proteins, Albumin, Urea, Creatinine, Alkaline Phosphatase, Alanine Aminotransferase, Aspartate Aminotransferase, Indirect Bilirubins, Direct Bilirubins and Total Bilirubins), and the of agglutinine title by the microscopic agglutination test (MAT). The animals were killed whit the reinforcement of the anesthesis, and necropsied for the collection of kidney and liver sample for histopathologic tests by staining of Hematoxylin-Eosina and Warthin-Starry, such as the isolation of leptospiras by cultivation into Fletcher´s medium. There were controls of the infecctious inoculum, antibiotic treatment and of the management system adopted. The number of DL 50 effectively applied in the infectious inoculum was 7,11. The antibiotic controls presented elevation of the alkaline phosphatase level and vacuolar degeneration of hepatocytes at the concentrations of 40 to 80 mg of antibiotic. The leptospire\'s kidney carriers were obtained in the animals treated with 40 or 80 mg of Erythromycin Estolate, regardless of the sex; these animals showed increase in creatinine\'s and total protein serum levels but of albumin, urea, alanine aminotransferase, aspartate aminotransferase, direct bilirubins, indirect bilirubins and total bilirubins were the same as found in animals not infected by leptospires and not treated with the antibiotic. The histological changes found in the animals induced as leptospires carrier were vacuolar degeneration in hepatocytes, blood in the portal tract, and glomerular congestion. The agglutinine titles for the homologous serovar, expressed on base 10 logarithm, were at least 1.19.
182

Análise das respostas citogenotóxicas e histopatológicas do peixe Trematomus newnesi exposto à água do mar diante da Estação Antártica Brasileira \"Comandante Ferraz\", Ilha Rei George, Antártica / Analysis of cytogenotoxic and histopathologic responses of the fish Trematomus newnesi exposed to seawater in front of the Brazilian Antarctic Research Station \"Comandandante Ferraz\", King George Island, Antarctica.

Debora Yamane Furquim Campos 17 September 2007 (has links)
Muitos países possuem estações de pesquisa instaladas na Antártica. Hidrocarbonetos de petróleo e os esgotos lançados no mar pelas estações são as fontes potenciais de poluição na Antártica. Peixes da espécie Trematomus newnesi foram utilizados para investigar o potencial genotóxico e os efeitos sobre a morfologia de fígado e brânquias da água diante dos tanques de combustível e da saída de esgoto da Estação Antártica Brasileira ?Comandante Ferraz?, em experimentos in situ e no laboratório. No Ensaio de Mn e ANE, observou-se que a freqüência de R foi, em geral, menor nos controles do que nos grupos expostos, tanto nos bioensaios como nos experimentos in situ, porém não houve diferenças estatisticamente significativas em nenhum dos experimentos. As lesões branquiais mais observadas, nos grupos expostos, foram hipertrofia do epitélio e telangiectasia lamelar. No fígado, as lesões predominantes foram a vacuolização lipídica e a presença de macrófagos, principalmente nos peixes dos experimentos in situ. Não foram verificadas diferenças significativas nos índices de lesões histopatológicas entre os grupos expostos e os controles em nenhum dos experimentos. Contudo, os resultados obtidos sugerem que dos dois locais analisados nas proximidades da Estação Brasileira, a saída de esgoto apresenta maior potencial de risco para T. newnesi. / Many countries have installed research stations in Antarctica. Petroleum hydrocarbons and the sewage disposed into the sea by the stations are potential sources of pollution in Antarctica. Trematomus newnesi specimens were used to assess genotoxic potential and histopathology of the liver and gills of the water surrounding the Brazilian Antarctic Station ?Comandante Ferraz?. Fish were exposed to seawater at the sewage outfall and in front of the fuel tanks, in both in situ and laboratory assays. The Mn and ENA assay showed that the frequency of R was, in general, lower in the control groups than in the exposed ones in both in situ and laboratory assays, however there were no statistically significative differences in any of the experiments. The most frequent branchial lesions observed in the exposed groups were epithelium hipertrophy and lamelar telangiectasis. In the liver, predominant microscopic findings included lipid vacuolization and macrophages, specially in fish from the in situ experiments. Exposed groups did not show significative differences in the histopathological indexes from those of the controls in any of the experiments. Nevertheless, our results suggest that of the places studied the sewage outlet may present a greater potential of risk to T. newnesi nearby the Brazilian Station.
183

Toxicidade aguda, comportamento e análises anatomopatológicas em diferentes espécies de peixes expostos à formulação comercial contendo deltametrina / Acute toxicity, behavior and anatomopathological analysis in different species of fish exposed to the commercial formulation containing deltamethrin

Sílvio Cesar de Osti 17 June 2005 (has links)
A toxicidade da formulação comercial contendo o praguicida piretróide deltametrina foi testada nas espécies de peixe Danio rerio, Hyphessobrycon bifasciatus, Geophagus brasiliensis e Oreochromis niloticus por meio de testes de toxicidade aguda, avaliação de alterações comportamentais e análises anatomopatológicas do fígado e das brânquias. A espécie D. rerio apresentou CL50;48h igual a 0,078µg L-1, a espécie H. bifasciatus apresentou CL50;48h igual a 0,082µg L-1, a espécie G. brasiliensis apresentou CL50;48h igual a 0,594µg L-1 e O. niloticus apresentou CL50;48h igual a 0,954µg L-1. As análises de comportamento realizadas com as espécies D. rerio e H. bifasciatus mostrou ser a segunda mais sensível ao praguicida, revelando alterações significativas nas menores doses de exposição. As análises anatomopatológicas realizadas com a espécie G. brasiliensis quando exposta à concentrações subagudas do praguicida mostrou vacuolização e degeneração nuclear hepática e nas brânquias a ocorrência de hiperplasia lamelar e fusão nas lamelas secundárias que aumentaram em função da concentração do praguicida e do tempo de exposição. Os resultados demonstraram elevada toxicidade do praguicida para todas as espécies testadas. / The toxicity of the commercial formulation containing the pesticide pirethroid deltamethrin was tested in the species of fish Danio rerio, Hyphessobrycon bifasciatus, Geophagus brasiliensis and Oreochromis niloticus through tests of acute toxicity, evaluation of behavioral alterations and anatomopathological analysis of the liver and of the gills. The species D. rerio presented LC50;48h equals to 0,078µg L-1, the species H. bifasciatus presented LC50;48h equals to 0,082µg L-1, the species G. brasiliensis presented LC50;48h equals to 0,594µg L- 1 and O. niloticus presented LC50;48h equals to 0,954µg L-1. The analysis of behavior accomplished with the species D. rerio and H. bifasciatus showed that the second one was more sensitive to the pesticide, and revealed significant alterations in the exhibition of fewer doses. The anatomopathological analysis accomplished with the species G. brasiliensis, when exposed to underacute concentrations of the pesticide, showed vacuolization and hepatical nuclear degeneration and the occurrence of lamellar hyperplasia in the gills plus fusion in the secondary lamellas which were increased due to the concentration of the pesticide and of the time of exposition. The results demonstrated high toxicity of the pesticide for all of the tested species.
184

The pathological and genomic impact of CTCF depletion in mammalian model systems

Aitken, Sarah Jane January 2018 (has links)
CCCTC-binding factor (CTCF) binds DNA, thereby helping to partition the mammalian genome into discrete structural and regulatory domains. In doing so, it insulates chromatin and fine-tunes gene activation, repression, and silencing. Complete removal of CTCF from mammalian cells causes catastrophic genomic dysregulation, most likely due to widespread collapse of 3D chromatin looping within the nucleus. In contrast, Ctcf hemizygous mice with lifelong reduction in CTCF expression are viable but have an increased incidence of spontaneous multi-lineage malignancies. In addition, CTCF is mutated in many human cancers and is thus implicated as a tumour suppressor gene. This study aimed to interrogate the genome-wide consequences of a reduced genomic concentration of Ctcf and its implications for carcinogenesis. In a genetically engineered mouse model, Ctcf hemizygous cells showed modest but robust changes in almost a thousand sites of genomic CTCF occupancy; these were enriched for lower affinity binding events with weaker evolutionary conservation across the mouse lineage. Furthermore, several hundred genes concentrated in cancer-related pathways were dysregulated due to changes in transcriptional regulation. Global chromatin structure was preserved but some loop interactions were destabilised, often around differentially expressed genes and their enhancers. Importantly, these transcriptional alterations were also seen in human cancers. These findings were then examined in a hepatocyte-specific mouse model of Ctcf hemizygosity with diethylnitrosamine-induced liver tumours. Ctcf hemizygous mice had a subtle liver-specific phenotype, although the overall tumour burden in Ctcf hemizygous and wild-type mice was the same. Using whole genome sequencing, the highly reproducible mutational signature caused by DEN exposure was characterised, revealing that Braf(V637E), orthologous to BRAF(V600E) in humans, was the predominant oncogenic driver in these liver tumours. Taken together, while Ctcf loss is partially physiologically compensated, chronic CTCF depletion dysregulates gene expression by subtly altering transcriptional regulation. This study also represents the first comprehensive genome-wide and histopathological characterisation of this commonly used liver cancer model.
185

Isolamento e identificação do papilomavírus bovino em grupo experimental de bovinos para obtenção de um banco de vírus. / Isolation and identification of bovine papillomavirus in experimental group of cattle in order to obtain a virus bank.

Araldi, Rodrigo Pinheiro 17 October 2014 (has links)
O Papilomavírus bovino (BPV) gera prejuízos à pecuária. O trabalho buscou isolar vírions de BPV de papilomas cutâneos previamente diagnosticados e avaliar o potencial clastogênico do vírus através do ensaio cometa (EC). O DNA tecidual foi extraído e submetido a PCR. As bandas foram purificadas e sequenciadas. As sequências foram analisadas através de bioinformática. A tipagem mostrou a prevalência de BPV-2. A análise histopatológica revelou acantose, coilocitose e hiperqueratose. Foi possível detectar a presença de fibroblastos transformados, sugerindo uma via de infecção através do sangue. A imuno-detecção das proteínas L1 e E7 no estroma sugere atividade transformadora do BPV em fibroblastos. O EC mostrou a ação clastogênica estatisticamente igual entre os tipos virais BPV-2, 5 e 9. O isolamento viral foi realizado através de ultracentrifugação em densidade única de cloreto de césio, empregando uma nova metodologia, que se mostrou menos laboriosa do que as já descritas, permitindo o isolamento de vírions de BPV-2, iniciando o banco de vírus proposto. / The Bovine papillomavirus (BPV) generates losses to livestock. The study sought to isolate BPV virions from cutaneous papillomas previously diagnosed and evaluate the clastogenic potential of the virus through the comet assay (EC). The tissue DNA was extracted and subjected to PCR. The bands were purified and sequenced. Sequences were analyzed using bioinformatics. The typing showed the prevalence of BPV-2. Histopathology showed acanthosis, hyperkeratosis and koilocytosis. It was possible to detect the presence of transformed fibroblasts, suggesting a route of infection through the blood. Immunohistochemical detection of L1 and E7 proteins in the stroma suggests transforming activity of BPV in fibroblasts. The EC clastogenic action showed statistically equal among the virus types BPV-2, 5 and 9. Viral isolation was performed by ultracentrifugation in a single cesium chloride density, using a new method that was less laborious than those already described, allowing the isolation of BPV-2 virions, starting the proposed stock virus.
186

Influência de diferentes concentrações de reinóides em formulações dermocosméticas nos efeitos benéficos e/ou colaterais na pele de camundongos sem pêlo / Influence of different concentrations of retinoids in dermocosmetic formulations in their beneficial and/or collateral effects in hairless mice skin.

Gomes, Maria Laura Costantini 28 February 2007 (has links)
Os retinóides têm sido amplamente utilizados na clínica dermatológica e nos produtos cosméticos com finalidades preventivas e reparadoras dos efeitos indesejáveis do envelhecimento cutâneo. Considerando que a concentração de retinóides, como por exemplo, o ácido retinóico ou o palmitato de retinila, pode influenciar na eficácia e segurança de uso dos mesmos em formulações tópicas, é de fundamental importância o desenvolvimento e avaliação dos efeitos benéficos e/ou colaterais de formulações dermocosméticas contendo diferentes concentrações de ácido retinóico (0,025%, 0,05% e 0,1%) e palmitato de retinila (0,25%, 0,5% e 1,0%), visando a obtenção de uma concentração que proporcione a máxima eficácia possível e risco mínimo à pele. Assim, o presente trabalho tem por objetivos avaliar a influência de diferentes concentrações de retinóides (ácido retinóico ou palmitato de retinila) em formulações dermocosméticas com finalidades antienvelhecimento, na pele de camundongos sem pêlo, por estudos histopatológicos, morfométricos, estereológicos e por Bioengenharia Cutânea. Para tal foram preparadas três formulações de géis creme à base de hidroxietilcelulose (HEC) e microemulsão de silicone e octanoato de octila (formulações de nos 1 e 3) e à base de complexo lipídico contendo álcool batílico e lecitina de soja, HEC e octanoato de octila (formulação de nº 2) as quais foram submetidas a testes preliminares de estabilidade. A formulação de nº 1 (F1) foi considerada a mais estável e, portanto, selecionada como veículo para a avaliação dos efeitos do ácido retinóico e do palmitato de retinila na pele de camundongos sem pêlo. Para a realização do ensaio biológico, amostras das formulações, acrescidas ou não (veículo) de 0,025; 0,05 ou 0,1% ácido retinóico ou 0,25; 0,5 ou 1,0% de palmitato de retinila foram aplicadas no dorso de camundongos sem pêlo. Após cinco dias da aplicação diária destas formulações, foram obtidas medidas de índice de eritema pelo equipamento Mexameter® MX16 e medidas do conteúdo aquoso do estrato córneo pelo equipamento Corneometer® CM825. Em seguida, os camundongos foram mortos e posteriormente foram colhidos fragmentos de pele das áreas que receberam aplicação das formulações, bem como da área que não foi aplicada nenhuma formulação (controle) e, a seguir, obtidos cortes histológicos para a realização dos estudos histopatológicos, morfométricos e estereológicos. De acordo com as metodologias empregadas, foi possível observar que, na avaliação do conteúdo aquoso do estrato córneo, somente as formulações que continham ácido retinóico em diferentes concentrações, provocaram mudanças significativas, reduzindo este conteúdo, ou seja, ocasionou um ressecamento na superfície da pele. Apenas as formulações contendo 0,025 e 0,1% de ácido retinóico e 1,0% de palmitato de retinila provocaram um aumento no índice de eritema. Além disso, tanto o ácido retinóico quanto o palmitato de retinila, atuaram na epiderme, porém de modo e intensidade diferentes, sendo que, o ácido retinóico teve um efeito mais pronunciado em relação às variáveis estudadas. As três diferentes concentrações de ácido retinóico e de palmitato de retinila ocasionaram aumento significante da espessura das camadas epiteliais, sem alteração da camada córnea. O ácido retinóico e o palmitato de retinila atuaram ainda aumentando os volumes nuclear, citoplasmático e celular, um dos fatores que ocasionou aumento da espessura do epitélio. Finalizando, ao analisar todas as variáveis histopatológicas, morfométricas e estereológicas, bem como o índice de eritema e o conteúdo aquoso do estrato córneo estudados, podemos sugerir que as formulações que continham as concentrações intermediárias, tanto do ácido retinóico (0,05%) quanto do palmitato de retinila (0,5 %), foram as que apresentaram melhores resultados, principalmente no que se refere a uma relação risco / benefício adequada e aceitável. / Retinoids has been widely used in dermatological clinic and in cosmetics products with preventive purposes as well as for the repairmen of the cutaneous aging undesirable effects. Considering that the concentration of retinoids, i.e., the retinoic acid or the retinyl palmitate, can influence their efficacy and safety in topical formulations, the development and evaluation of the beneficial and/or collateral effect of dermocosmetic formulations containing different concentrations of retinoic acid (0.025%, 0.05% e 0.1%) and retinyl palmitate (0.25%, 0.5% e 1.0%) is very important, aiming at the attainment of a concentration that provides to the maximum possible efficacy and minimum risk to the skin. Thus, the aim of this study was to evaluate the influence of different concentrations of retinoids (retinoic acid or retinyl palmitate) in dermocosmetics formulations with antiaging purposes, in hairless mice, using histopathological, morphometric and stereologic studies and Skin Bioengineering Techniques. For this purpose, three gel cream formulations were developed, containing hydroxyethylcellulose (HEC) and silicone microemulsion and octyl octanoate (formulations nº 1 and 3) and a complex lipidic based formulation containing batyl alcohol and lecithin, HEC and octyl octanoate (formulation nº 2), which were submitted to preliminary stability tests. The formulation nº1 (F1) was considered the most stable, therefore, it was selected as the vehicle for the evaluation of the effects of the retinoic acid and the retinyl palmitate in hairless mice skin. For the accomplishment of the biological assay, samples of the formulations, supplemented or not (vehicle) of 0.025, 0.05 or 0.1% retinoic acid or 0.25, 0.5 or 1.0% retinyl palmitate were applied in the dorsal skin of hairless mice. After five days of daily application of these formulations, the erythema index was measured by reflectance spectrophotometry using a Mexameter® MX16 as well as the water content of the stratum corneum using Corneometer® CM825. After that, the hairless mice were sacrificed and later skin fragments were obtained for each area that received application of the formulations, as well as of the area that was not applied any formulation (control) and, after that histologic sections were obtained and submitted to histopathological, morphometric and stereologic studies. In accordance with the used methodologies, it was possible to observe that in the evaluation of the water content of the stratum corneum, only the formulations that contained retinoic acid in different concentrations provided significant changes, enhancing skin surface dryness. Only the formulations containing 0.025 and 0.1% of retinoic acid and 1.0% of retinyl palmitate provided an increase in erythema index. Moreover, both retinoic acid and retinyl palmitate acted in the epidermis, however in different intensity and way, since retinoic acid had more pronounced effects in relation to the studied variables. The three different concentrations of retinoic acid and retinyl palmitate caused a significant increase of the epithelial layers thickness, without alteration of the horny layer. Retinoic acid and retinyl palmitate also increased the nucleus, cytoplasmic and cell volumes, which was one of the factors that influenced the increase of the epithelium thickness. Finishing, when analyzing all the histopathological, morphometric and stereologic variables, as well as the erythema index and the water content of the stratum corneum studied, we can suggest that the formulations that contained the intermediate concentrations (such as 0.05% of retinoic acid and 0.5% of retinyl palmitate) presented the best results, mainly when an adequate and acceptable risk/ benefit relationship is considered.
187

Etude in vivo du rôle potentiel de la phospholipase A2 de groupe IIA humaine dans le paludisme : Caractérisation de la physiopathologie de l'infection à Plasmodium chabaudi chez la souris C57BL/6 transgénique pour l'enzyme / In vivo study of the potential role of group IIA phospholipase A2 in malaria : Pathophysiological characterization of C57BL/6 group IIA phospholipase A2 transgenic mice infected with Plasmodium chabaudi

Dacheux, Mélanie 28 September 2018 (has links)
Le paludisme est une maladie tropicale causée par un parasite du genre Plasmodium. Chez l’Homme, un niveau élevé de phospholipase A2 sécrétée de groupe IIA humaine (hGIIA) est mesuré dans le plasma des patients impaludés. Cette enzyme est connue pour son rôle antibactérien et pro-inflammatoire. Cependant, son rôle dans le paludisme n’a jamais été exploré. Pour comprendre le rôle in vivo de la hGIIA dans cette pathologie, nous avons entrepris la caractérisation hématologique, histopathologique et immunohistochimique de l’infection de souris C57BL/6, transgéniques (Tg+) pour l’enzyme humaine, par l’espèce murine Plasmodium chabaudi chabaudi 864VD. Ce modèle reproduit un paludisme non létal. Nos résultats ont permis d’établir que les souris Tg+ ont un meilleur contrôle de l’infection au moment du pic de crise parasitaire (J14 post-inoculation), avec une diminution de 27% de la parasitémie, comparé aux souris « littermates » non transgéniques (Tg-). L’injection de hGIIA recombinante aux jours 12, 13 et 14 p.i. (0,125 mg/kg deux fois par jour) à des souris C57BL/6 wild-type (WT) infectées par P. c. chabaudi 864VD provoque une diminution d’environ 19% de la parasitémie à J14 p.i., démontrant un rôle direct de la hGIIA dans la diminution de la population parasitaire. Les données hématologiques montrent que l’infection chez la souris Tg+ provoque une anémie plus durable que chez la souris Tg- et une élévation nettement plus importante du nombre de leucocytes, en particulier des polynucléaires neutrophiles. Chez la souris Tg+ parasitée, on observe aussi l’activation d’un nombre important de lymphocytes et une activation spécifique des monocytes avant le pic de crise. Chez la souris Tg- infectée, les données histologiques mettent en avant une meilleure récupération des lésions histopathologiques du foie et une hyperplasie des lymphocytes B dans la rate, tandis que les souris Tg+ infectées présentent des lésions hépatiques tardives et une hématopoïèse extramédullaire splénique. Les résultats des analyses par RT-qPCR suggèrent que l’ARNm de la hGIIA augmente au pic parasitaire dans le foie des souris Tg+ infectées, mais diminue dans la rate et les cellules sanguines. L’injection de hGIIA recombinante au début de la phase patente est sans effet sur la parasitémie, ce qui laisse supposer que des événements plus tardifs dans l’infection sont nécessaires à l’activité antiparasitaire de l’enzyme. L’étude du rôle des lipoprotéines oxydées comme substrat potentiel de l’activité antiparasitaire de l’enzyme, basée sur des résultats in vitro, est abordée. En conclusion, nos études ont permis de dresser un tableau large de l’infection à Plasmodium chez la souris exprimant la hGIIA, et ouvrent de nouvelles perspectives dans l’analyse du rôle de l’enzyme dans la physiopathologie du paludisme. / Malaria is a tropical disease caused by a parasite of the Plasmodium genus. High levels of circulating human group IIA secreted phospholipase A2 (hGIIA) have been reported in malaria patients. The enzyme is well known for its bactericidal and pro-inflammatory actions. However, so far its role in malaria is unknown. In order to address the in vivo role of hGIIA in malaria, we performed a hematological, histopathological and immunohistochemical characterization of C57BL/6 hGIIA transgenic mice (Tg+ mice) infected with P. chabaudi chabaudi (864VD strain), a murine Plasmodium species and strain which causes non-lethal chronic malaria. Infected Tg+ mice present a 27% reduction of parasitaemia at the peak of infection (D14 post-inoculation, p.i.) compared to infected non-transgenic littermates (Tg- mice). Intraperitoneal injection of recombinant hGIIA at D12, D13 and D14 p.i. (0.125 mg/kg twice a day) into P. chabaudi 864VD-infected WT C57BL/6 mice leads to a 19% reduction of the parasitaemia at D14 p.i., demonstrating the direct and acute role of hGIIA in lowering parasite population and presumably ruling out a potential effect linked to chronic overexpression of hGIIA in Tg+ mice. Hematological data show a durable anemia in Tg+ mice compared to Tg- mice during the infection and an important increase of leucocytes, especially of polynuclear neutrophils. The parasitized Tg+ mouse also presents a higher activation of lymphocytes and a specific activation of monocyte cells at the pic of crisis. In the infected Tg- mouse, histological data show a better histopathological recovery in the liver and B cells hyperplasia in the spleen, whereas the infected Tg+ mouse presents late hepatic injuries and splenic extra-medullar hematopoiesis. RT-qPCR analyses suggest that hGIIA mRNA increases at the pic of infection in the liver of infected Tg+ mice, but decreases in spleen and blood. Intraperitoneal injection of recombinant hGIIA at the patent phase is without effect on parasitaemia, which suggests that later infection events are needed for the enzyme antiparasitic activity. Involvement of oxidized-lipoproteins as potential hGIIA substrates, based on in vitro studies, is discussed. In conclusion, our studies allowed us to elaborate a larger picture of the infection of Plasmodium in the mice expressing hGIIA and open new perspectives in the analysis of the role of the enzyme in malaria pathophysiology.
188

Die Subfertilität der Sportstute: welchen Einblick gewährt die histopathologische Untersuchung von Endometriumbioptaten? / Subfertility in sports mares: which insight is gained by the histopathological examination of endometrial biopsies?

Kilgenstein, Helen 12 June 2014 (has links) (PDF)
Unter Praxisbedingungen gilt die Erstbelegung einer Sportstute nach Beendigung der sportlichen Karriere als problematisch, viele Sportpferde konzipieren erst nach einer mehrjährigen Pause. Bisher existieren nur wenige wissenschaftliche Studien zu diesem Thema, in diesen ist die Problematik nur teilweise und ausschließlich unter klinischen Gesichtspunkten analysiert worden. Gegenstand dieser Arbeit ist die histopathologische Untersuchung der Endometriumbioptate von Sportstuten im Hinblick auf Befunde, die eine Erklärung für die bei Sportstuten häufig beobachtete Subfertilität darstellen können. Bei den Sportstuten dieser Studie handelte es sich um Stuten mit einer regelmäßigen Partizipation an Turnieren der Klasse M oder S, sowie um internationale Sportpferde, die in 3 Gruppen aufgeteilt wurden (Gruppe 1: seit dem Einsatz im Sport noch nicht besamte Stuten, n= 68; Gruppe 2: seit dem Einsatz im Sport erfolglos besamte Stuten: n= 84; Gruppe 3: Stuten, die seit dem Einsatz im Sport ein oder mehrmals abgefohlt haben, n= 37). Die an den Endometriumbioptaten der Sportstuten erhobenen Daten wurden überdies mit denen einer vierten Gruppe, bestehend aus Freizeitpferden (n= 31) verglichen. Auffällig häufig konnten in Gruppen 1 und 2 Differenzierungsstörungen in Bioptaten, die während der Decksaison entnommen wurden, beobachtet werden; dabei handelt es sich um Endometriopathien, deren Auftreten in der equinen Reproduktionsmedizin häufig auf hormonelle Imbalancen zurückgeführt wird. Von den Sportstuten der Gruppen 1 und 2, welche weniger als 1 Jahr vor Bioptatentnahme noch im Sport eingesetzt wurden, zeigten 16% (5/31) eine glanduläre Inaktivität. Dabei handelt es sich um einen histopathologischen Befund, der auf eine stark eingeschränkte Ovarfunktion schließen lässt. Eine irregulär proliferative Differenzierung des Endometriums wiesen 16% (5/32) der Stuten auf, die circa ein Jahr zuvor ihre Karriere im Sport beendet hatten. Solche, die bereits längere Zeit (≥2 Jahre) pausierten, zeigten vermehrt eine irregulär sekretorische Differenzierung des Endometriums (37%; 7/19). Die diagnostizierten Formen endometrialer Fehldifferenzierung, insbesondere in der zeitlichen Reihenfolge ihres Vorkommens, sprechen dafür, dass bei diesen Stuten unmittelbar nach dem Sport eine Ovarialinsuffizienz vorliegt, und dass die Rückkehr in ein reguläres Zyklusgeschehen begleitet wird von verschieden Störungen der Ovarfunktion. Dabei scheint der Schweregrad der ovariellen Dysfunktion mit fortschreitender Dauer seit dem Einsatz im Sport abzunehmen. Die irregulär proliferative Differenzierung wurde signifikant häufiger bei Stuten beobachtet, die vorberichtlich im Präöstrus bioptiert worden waren (p= 0,016); die irregulär sekretorische und die vollständig irreguläre Differenzierung traten häufiger bei im Interöstrus bioptierten Stuten auf. Die Ergebnisse lassen darauf schließen, dass ein Zusammenhang zwischen der Art der irregulären Differenzierung und dem Zyklusstand besteht. In Bezug auf weitere anamnestische Daten, wurde die irreguläre endometriale Differenzierung überdies gruppenübergreifend signifikant häufiger bei Stuten älter als 15 Jahre beobachtet; außerdem zeigten alle vorberichtlich azyklischen bzw. unregelmäßig zyklierenden Stuten (n= 5), alle Stuten mit Ovartumoren (n= 2), sowie eine Stute mit vorberichtlich Ovarzysten und eine mit sogenannten „intrauterine devices“ ein irregulär differenziertes Endometrium. In dieser Arbeit konnte gruppenübergreifend ein signifikanter Zusammenhang zwischen dem Auftreten von degenerativen Veränderungen des Endometriums (Endometrose: p= 0,008; Angiosklerose: p= 0,002) und dem Alter einer Stute nachgewiesen werden; die bei den Sportstuten gewonnen Daten unterschieden sich allerdings kaum merklich von den bei Zuchtstuten erhobenen Daten aus der Literatur. Endometritiden konnten vor allem bei seit dem Einsatz im Sport erfolglos besamten Stuten (Gruppe 2; 31%) nachgewiesen werden und bei ehemaligen Sportstuten, die seit ihrem Einsatz bereits erfolgreich konzipiert hatten (Gruppe 3; 41%). Der Prozentsatz an Stuten mit Endometritiden war in diesen Gruppen höher als der in der Literatur beschriebene Anteil bei „Nicht-Sportstuten“. Eine mögliche Erklärung für das gehäufte Auftreten von Endometritiden bei diesen Stuten stellen darum wiederholte Besamungsversuche dar, und -bei Stuten der Gruppe 3- auch postpartale Involutionsstörungen. Nach dem Kategorisierungssystem von KENNEY und DOIG (1986) hatten seit dem Einsatz im Sport noch nicht besamte Sportstuten (Gruppe 1) bessere Kategorie als Hobbystuten (Gruppe 4). Die in der vorliegenden Untersuchung bei Sportstuten diagnostizierten Differenzierungsstörungen fließen jedoch nicht in dieses Kategorisierungssytem ein. Bei Sportstuten reicht somit die alleinige Anwendung des Kategorisierungssystems für die Beurteilung einer möglichen Fertilitätsminderung nicht aus; deshalb wird eine ausführliche histopathologische Beurteilung eines Endometriumbioptats unter Einbeziehung der glandulären Funktionsmorphologie empfohlen. Zusammenfassend kann davon ausgegangen werden, dass die beobachteten degenerativen Veränderungen des Endometriums, die bei Sportstuten hinsichtlich Grad und Ausprägung mit denen von Nichtsportstuten vergleichbar waren, keine mögliche Erklärung für die Reproduktionsstörungen von Sportstuten darstellen. Vielmehr lassen die im Rahmen dieser Arbeit erhobenen histopathologischen Befunde vermuten, dass bei Sportstuten Differenzierungsstörungen des Endometriums während der Decksaison eine wichtige Ursache der klinisch beobachteten Subfertilität darstellen. Der Nachweis dieser Veränderungen deutet auf ein gehäuftes Auftreten von hormonellen Störungen, ausgelöst durch ovarielle Dysfunktionen hin; zum abschließenden Beweis bedarf es allerdings klinischer Studien.
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Estudo comparativo entre lesões cariosas artificiais e naturais de esmalte com relação à permeabilidade da camada superficial

Ferreira, Danilo Augusto de Holanda 27 March 2014 (has links)
Made available in DSpace on 2015-05-14T12:56:03Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 946361 bytes, checksum: 1766fac9ee5a060f38a21f6c3c424890 (MD5) Previous issue date: 2014-03-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to compare artificial carious enamel lesions induced with an acid gel containing large amounts of organic matter and artificial carious lesions induced by an acidic solution (with little organic constituent) regarding organic volume and permeability (&#61537;d). Thirty teeth (twenty third molar and ten molars with inactive white spot lesions) were divided into three groups. In order to induce artificial caries, ten teeth were exposed to an acid gel containing hydroxyethylcellulose 2% and 50 mM lactic acid at pH 4.5 (Gel; n = 10) while the other ten teeth a demineralizing solution (0,1 mM lactic acid, 11.7 mM of calcium, chloroform 0.5% v/v, 6 mM phosphate, pH 4.5) (Solution; n = 10). As a control group, the teeth containing white spot lesions were also analyzed (Natural Caries, n = 10). Three points were analyzed in each sample at the surface layer in each lesion at 50&#956;m intervals. The results obtained in each of the three groups were compared with theoretical mathematical found values in the literature as a way to standardize the comparison. Finally, variations in organic volume (Ratio &#61538;) and permeability (Ratio &#61537;d) in relation to predicted values were compared between groups. For variable Ratio &#61538;, there was a significant difference between the gel and solution [p<0.0001, ANOVA; Effect Size (ES)=1.84] and between solution and the natural caries (p=0.001, ANOVA; ME=0.46). Similarly, the values of Ratio &#61537;d between Gel/Solution (p<0.0001, Mann-Whitney, ES=0.96) and Solution/Natural caries (p<0.0001; Mann-Whitney; ME=1.15) differed significantly. There was no statistically significant difference between the groups Gel and Natural Caries for Ratio &#61538; (p=0.585, ANOVA, ES=0.30) and the Ratio &#61537;d (p=0.940, Mann-Whitney, ES=0.01). It was concluded that, as in natural decay, the surface layer of artificial carious enamel lesions created with organic acid gel showed higher organic matter and lower permeability compared to those induced in acidic solution. / O objetivo deste estudo foi comparar lesões cariosas artificiais de esmalte induzidas com gel ácido contendo grande quantidade de matéria orgânica e lesões cariosas artificiais induzidas com solução ácida com pouco constituinte orgânico, quanto ao volume orgânico e à permeabilidade (&#61537;d). Trinta dentes (vinte terceiros molares inclusos e dez molares com lesão de mancha branca inativa) foram distribuídos em três grupos. Com o intuito de se induzir cárie artificial, dez dentes inclusos foram expostos a um gel ácido de hidroxietilcelulose 2% e ácido lático 50 mM com pH 4,5 (Gel; n=10) e os outros dez a uma solução desmineralizante (0,1 mM de ácido lático, 11,7 mM de cálcio, clorofórmio 0,5% v/v e 6 mM de fosfato, com pH 4,5) (Solução; n=10). Como grupo controle, os dentes contendo lesões de mancha branca também foram analisados (Cárie Natural; n=10). De cada amostra analisou-se três pontos da camada superficial da lesão, em intervalos de 50 &#956;m. Os pontos analisados em cada um dos três grupos foram comparados com valores teóricos estabelecidos matematicamente na literatura, como forma de padronizar as comparações. E, por fim, as variações de volume orgânico (Razão &#61538;) e permeabilidade (Razão &#61537;d) em relação a valores previstos foram comparadas entre os grupos. Para a variável Razão &#61538;, houve diferença significante entre os grupos Gel e Solução [p<0,0001, ANOVA; Magnitude do efeito (ME)=1,84] e entre Solução e Cárie Natural (p=0,001; ME=0,46; ANOVA). Da mesma forma, os valores da Razão &#61537;d do cruzamento Gel/Solução (p<0,0001, Mann-Whitney; ME=0,96) e Solução/Cárie Natural (p<0,0001, Mann-Whitney; ME=1,15) diferiram de maneira significativa. Não houve diferença estatisticamente significante entre os grupos Gel e Cárie Natural para a Razão &#61538;&#61472;(p=0,585; ANOVA; ME=0,30) e a Razão &#61537;d (p=0,940; Mann-Whitney; ME=0,01). Concluiu-se que, semelhantemente à cárie natural, a camada superficial das lesões cariosas artificiais de esmalte criadas com gel ácido apresentaram maior volume orgânico e menor permeabilidade, comparadas às induzidas em solução ácida.
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Características ultrassonográficas de massas pélvicas anexiais e concordância entre o exame transoperatório de congelação e o anatomopatológico convencional

Amaral, Clarissa de Andrade Gonçalves do January 2012 (has links)
Objetivo: Avaliar a concordância entre o exame anatomopatológico transoperatório de congelação (TO) e o diagnóstico histológico no exame anatomopatológico convencional (AP-conv) nas massas anexiais, divididas em grupos conforme seu tamanho e suas características morfológicas na ultrassonografia da pelve, para especificar fatores ultrassonográficos preditores de erro no TO. Os diagnósticos do TO nos grupos foram comparados com os AP-conv de tumores benignos, borderline e malignos. Métodos: Estudo transversal com avaliação retrospectiva em 302 pacientes com diagnóstico ultrassonográfico de massas anexiais, submetidas a procedimento cirúrgico no Hospital de Clínicas de Porto Alegre. Estas foram divididas em oito grupos, conforme as características morfológicas ultrassonográficas e o tamanho tumoral. Grupo 1: tumores uniloculares ≤ 10 cm; grupo 2: tumores líquidos septados ≤ 10 cm; grupo 3: tumores heterogêneos ≤ 10 cm; grupo 4: tumores sólidos ≤ 10 cm; grupo 5: uniloculares > 10 cm; grupo 6: líquidos septados > 10 cm; grupo 7: heterogêneos > 10 cm; e grupo 8: sólidos > 10 cm. O resultado diagnóstico do TO foi então comparado com o diagnóstico histológico final no AP-conv. Resultados: A concordância diagnóstica variou entre os grupos. Nos 33 casos do grupo 1, houve 100% de concordância (Kappa 1) entre o TO e o AP-conv. No grupo 2, com 32 casos, também houve 100% de concordância, assim como nos seis casos do grupo 8 (Kappa 1). No grupo 3, com 90 casos, a concordância diagnóstica também foi ótima (Kappa 0,898), com dois casos discordantes (2,22%): um diagnóstico benigno no TO que se confirmou borderline no AP-conv e outro benigno no TO que se confirmou maligno no AP-conv. O grupo 4, com 24 casos, apresentou uma discordância (4,17%) de benigna no TO e maligna no AP-conv (Kappa 0,869). No grupo 5, houve concordância em 93% dos 15 casos, com uma discordância (6,67%) no diagnóstico: benigno no TO e maligno no AP-conv; não foi possível calcular o Kappa neste grupo. Dos 39 casos do grupo 6, 89,74% tiveram o diagnóstico concordante, com duas discordâncias (5,13%): benignos no TO foram borderline no AP-conv; uma discordância (2,57%): borderline no TO foi benigno no AP-conv; e outra discordância (2,57%): borderline no TO foi maligno no AP-conv (Kappa 0,591). O grupo 7, com 63 pacientes, teve concordância em 55 casos (87,30%), com oito casos discordantes (12,70%): dos seis benignos (9,52%) no TO, três foram borderline (4,76%) e três malignos (4,76%) no AP-conv; dos dois borderline (3,18%) no TO, um foi benigno (1,59%) e um maligno (1,59%) no AP-conv (Kappa 0,776). Conclusão: O TO tem uma concordância com o AP-conv que varia de ótima em tumores císticos a moderada em tumores multiloculados com mais de 10 cm. Nosso estudo apresenta limitações por ser um estudo retrospectivo, além de não haver sido o mesmo patologista quem avaliou todas as peças. Mas a estratificação das massas anexiais em grupos, de acordo com seu tamanho e características morfológicas na ultrassonografia, é um bom método para avaliação pré-operatória de massa anexiais, sabendo-se que, nas lesões císticas septadas ou com componentes sólidos maiores que 10 cm, a concordância do TO com o AP-conv é moderada. Portanto, devemos estar cientes que, em tumores maiores de 10 cm com componente sólido, o erro diagnóstico do TO aumenta. Assim, nesses casos, o patologista e o cirurgião deverão estar atentos para um correto diagnóstico e um planejamento adequado do tratamento, evitando, com isso, o subtratamento ou o sobretratamento da paciente. / Objective: To assess agreement between intraoperative frozen section (IFS) and final histopathology (HPE) for anatomic pathology examination of adnexal masses stratified according to size and morphological characteristics on pelvic ultrasonography and define sonographic predictors of diagnostic error of IFS. IFS classification of masses as benign, borderline, or malignant was compared to final diagnoses after HPE. Methods: Cross-sectional study with retrospective assessment of 302 patients with a sonographic diagnosis of adnexal masses that underwent surgical treatment at Hospital de Clínicas de Porto Alegre. Patients were divided into eight groups according to mass size and sonographic morphology as follows: Group 1, unilocular tumors ≤10 cm in size; Group 2, septated cystic tumors ≤10 cm in size; Group 3, heterogeneous tumors ≤10 cm in size; Group 4, solid tumors ≤10 cm in size; Group 5, unilocular tumors >10 cm in size; Group 6, septated cystic tumors >10 cm in size; Group 7, heterogeneous tumors >10 cm in size; and Group 8, solid tumors >10 cm in size. The diagnostic findings of IFS were then compared with the final histopathologic diagnosis. Results: Diagnostic agreement varied among groups. In Groups 1 (33 cases), 2 (32 cases), and 8 (6 cases), there was 100% agreement between IFS and HPE (Kappa = 1.0). In Group 3 (90 cases), agreement was excellent (Kappa = 0.898), with only two divergences (2.22%): one mass classified as benign on IFS that was borderline on HPE and another initially classified as benign that later proved malignant on HPE. In Group 4 (24 cases), Kappa was 0.869, with one divergence (4.17%), again a mass classified as benign on IFS which proved malignant on HPE. In Group 5, there was agreement in 93% of 15 cases, with one divergence (6.67%) in diagnosis: benign on IFS and malignant on HPE. Kappa could not be calculated for this group. Of the 39 cases in Group 6, there was agreement in 89.74%, with two masses classified as benign on IFS later deemed malignant on HPE (5.13%); one borderline on IFS diagnosed as benign on HPE (2.57%); and one borderline on IFS and diagnosed as malignant on HPE (2.57%) (Kappa = 0.591). In Group 7 (63 patients), there was agreement in 55 cases (87.30%), with eight divergences (12.70%): of six masses deemed benign on IFS (9.52%), three (4.76%) were diagnosed as borderline and three (4.76%) as malignant on HPE; of two masses deemed borderline on IFS (3.18%), one was later deemed benign (1.59%) and one diagnosed as malignant (1.59%) on HPE (Kappa = 0.776). Conclusion: Agreement between IFS and HPE ranged from excellent (for cystic masses) to moderate (for multilocular tumors larger than 10 cm). Limitations of this study include its retrospective design and the fact that not all surgical specimens were examined by the same pathologist. Nevertheless, stratification of adnexal masses by sonographic morphology and size is a good method for preoperative assessment, with the knowledge that agreement between IFS and HPE is only moderate for septated cystic or heterogeneous lesions larger than 10 cm. Therefore, clinicians should bear in mind that the diagnostic error of IFS is higher for adnexal masses >10 cm in size with a solid component. In these cases, particular care is required from both the pathologist and surgeon for proper diagnosis and treatment planning, thus avoiding undertreatment or overtreatment.

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