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

Efeitos tóxicos da \"Ipomoea carnea\" em caprinos. II - estudos de teratogenicidade / Toxic effects of the Ipomoea carnea in goats. 11- studies of teratogenicity

Henrique, Breno Schumaher 01 July 2005 (has links)
A Ipomoea carnea, pertencente à família das Convolvulaceae, é uma planta tóxica que tem ampla distribuição pelo país, tendo como principal princípio ativo a suainsonina. É uma das poucas plantas que se conserva verde durante a seca, podendo servir como fonte de matéria verde para bovinos, ovinos e caprinos, é nesse período, quando normalmente ocorrem os casos de intoxicação, sendo a espécie caprina a mais susceptível. Até o momento, não há relatos sobre efeitos tóxicos desta planta em conseqüência da possível passagem transplacentária da suainsonina. Assim, o objetivo do presente estudo foi avaliar os possíveis efeitos teratogênicos da I. carnea, em caprinos. Foram usados 20 cabras, divididas em 4 grupos iguais: 3 experimentais e 1 controle. As cabras dos grupos experimentais receberam a partir do 27° dia de prenhez até o final da gestação 1,0; 5,0 e 7,5 glkg/dia de I. carnea. Nas fêmeas gestantes foi feito o exame clínico periódico, colheita de sangue para avaliação do hemograma e bioquímica sanguínea, exames fetais ultra-sonográficos (US) e acompanhamento do parto. Ao nascimento, todos os filhotes foram avaliados para identificação de malformações, alguns foram submetidos à eutanásia, para a realização do estudo anatomopatológico e nos demais avaliou-se o ganho de peso, hemograma e bioquímica sanguínea. Os resultados obtidos mostraram que apenas as fêmeas que receberam 7,5g/kg de I.carnea apresentaram sintomatologia nervosa. No estudo US feito na 5°, 7° e 9° semana, observou-se redução significante dos movimentos fetais, de todos os animais experimentais. Alterações hematolágicas e na bioquímica sérica (como o aumento dos níveis sérico de glicose, aspartato amino transferase, uréia, fosfatase alcalina, albumina e diminuição dos níveis sé ricos de gama-glutamil transferase e colesterol) foram observadas em cabras dos grupos experimentais. No estudo histopatológico foram observadas vacuolizacões em diversos tecidos (fígado, rim e no sistema nervoso central). Na 10° semana de gestação uma cabra, tratada com a maior dose, abortou espontaneamente um feto, o qual apresentou artrogripose e ausência do fechamento da cavidade abdominal. Ao nascimento, verificou-se a ocorrência de mal formações fetais em filhotes caracterizada por retroagnatia, contratura congênita múltipla dos membros e artrogripose. Estes achados permitem concluir, que a ingestão da I. carnea durante a gestação de cabras, além de causar toxicidade materna, pode causar efeitos teratogênicos e que o US pode ser útil para acompanhar a ocorrência de efeitos nocivos desencadeados pela planta, durante a vida intra-uterina. / Ipomoea carnea (Convolvulaceae) is a toxic plant largely distributed throughout Brazil. The alkaloid swainsonine is the major active compound present in the plant. I. Carnea is resistent to drought, serving during this adverse climatic condition as a food source for cattle, sheeps and goats. It is well known that the ingestion of the plant promotes toxic effects to the animais, in particular to goats, the most susceptible specie. There are no reports about toxic effects of the plant to fetuses as a consequence of a possible placental transportation of the compound swainsonine. The objective of the present study was to evaluate the possible teratogenic effects of I. Carnea in goats. In the study 20 female goats were employed, divided into 4 groups: 3 experimental and 1 control. The experimental goats received from gestation day (GD) 27 to parturition day 1.0, 5.0 or 7.5 g/Kglday of I.carnea fresh leaves. Duringpregnancy the females were periodically accompanied by hematologic studies as hemograms and serum biochemical assays, ultrasonographic (US) fetuses assays and were accompanied during parturition. At post-natal day (PND) 01 ali the pups were evaluated for identificationof physical anormalities. Some were euthanized for histopathologic studies and the others had weight gain, hemograms and biochemical blood tests recorded during development. The obtained data showed that only the 7.5 g/Kg/day treated dams presented neurologic effects. The US study realized at the 5th,6thand th weeks of gestation, showed that ali the experimental groups presented significant reduction of the fetal intrauterine moviments. Hematologic and serum blood biochemical alterations (Iike increased levels of glucose, aspartate-amine transferase, urea, alkaline phosphatase, albumine and reduced levels of gamma-glutamyl transferase and cholesterol) were observed in goats of the experimental groups. The histopathologic study showed vacuolization in several tissues (liver,kidneys and brain). At the 10thweek of gestation one goat, treated with the increased dose, aborted a fetus. This fetus presented arthrogriposis and no closure of the abdominal cavity.At parturition(PND01) fetal malformationswere observed and characterized as retrognatia, multiple congenit contracture of the members and arthrogriposis. The present data showed that I. Carnea ingestion by pregnant goats promoted maternal toxicityand fetal teratogenic effects. In addition, the US showed to be an important tool to monitorize the toxic effects promoted by the plant ingestion during intrauterine life.
12

Efeitos tóxicos da \"Ipomoea carnea\" em caprinos. II - estudos de teratogenicidade / Toxic effects of the Ipomoea carnea in goats. 11- studies of teratogenicity

Breno Schumaher Henrique 01 July 2005 (has links)
A Ipomoea carnea, pertencente à família das Convolvulaceae, é uma planta tóxica que tem ampla distribuição pelo país, tendo como principal princípio ativo a suainsonina. É uma das poucas plantas que se conserva verde durante a seca, podendo servir como fonte de matéria verde para bovinos, ovinos e caprinos, é nesse período, quando normalmente ocorrem os casos de intoxicação, sendo a espécie caprina a mais susceptível. Até o momento, não há relatos sobre efeitos tóxicos desta planta em conseqüência da possível passagem transplacentária da suainsonina. Assim, o objetivo do presente estudo foi avaliar os possíveis efeitos teratogênicos da I. carnea, em caprinos. Foram usados 20 cabras, divididas em 4 grupos iguais: 3 experimentais e 1 controle. As cabras dos grupos experimentais receberam a partir do 27° dia de prenhez até o final da gestação 1,0; 5,0 e 7,5 glkg/dia de I. carnea. Nas fêmeas gestantes foi feito o exame clínico periódico, colheita de sangue para avaliação do hemograma e bioquímica sanguínea, exames fetais ultra-sonográficos (US) e acompanhamento do parto. Ao nascimento, todos os filhotes foram avaliados para identificação de malformações, alguns foram submetidos à eutanásia, para a realização do estudo anatomopatológico e nos demais avaliou-se o ganho de peso, hemograma e bioquímica sanguínea. Os resultados obtidos mostraram que apenas as fêmeas que receberam 7,5g/kg de I.carnea apresentaram sintomatologia nervosa. No estudo US feito na 5°, 7° e 9° semana, observou-se redução significante dos movimentos fetais, de todos os animais experimentais. Alterações hematolágicas e na bioquímica sérica (como o aumento dos níveis sérico de glicose, aspartato amino transferase, uréia, fosfatase alcalina, albumina e diminuição dos níveis sé ricos de gama-glutamil transferase e colesterol) foram observadas em cabras dos grupos experimentais. No estudo histopatológico foram observadas vacuolizacões em diversos tecidos (fígado, rim e no sistema nervoso central). Na 10° semana de gestação uma cabra, tratada com a maior dose, abortou espontaneamente um feto, o qual apresentou artrogripose e ausência do fechamento da cavidade abdominal. Ao nascimento, verificou-se a ocorrência de mal formações fetais em filhotes caracterizada por retroagnatia, contratura congênita múltipla dos membros e artrogripose. Estes achados permitem concluir, que a ingestão da I. carnea durante a gestação de cabras, além de causar toxicidade materna, pode causar efeitos teratogênicos e que o US pode ser útil para acompanhar a ocorrência de efeitos nocivos desencadeados pela planta, durante a vida intra-uterina. / Ipomoea carnea (Convolvulaceae) is a toxic plant largely distributed throughout Brazil. The alkaloid swainsonine is the major active compound present in the plant. I. Carnea is resistent to drought, serving during this adverse climatic condition as a food source for cattle, sheeps and goats. It is well known that the ingestion of the plant promotes toxic effects to the animais, in particular to goats, the most susceptible specie. There are no reports about toxic effects of the plant to fetuses as a consequence of a possible placental transportation of the compound swainsonine. The objective of the present study was to evaluate the possible teratogenic effects of I. Carnea in goats. In the study 20 female goats were employed, divided into 4 groups: 3 experimental and 1 control. The experimental goats received from gestation day (GD) 27 to parturition day 1.0, 5.0 or 7.5 g/Kglday of I.carnea fresh leaves. Duringpregnancy the females were periodically accompanied by hematologic studies as hemograms and serum biochemical assays, ultrasonographic (US) fetuses assays and were accompanied during parturition. At post-natal day (PND) 01 ali the pups were evaluated for identificationof physical anormalities. Some were euthanized for histopathologic studies and the others had weight gain, hemograms and biochemical blood tests recorded during development. The obtained data showed that only the 7.5 g/Kg/day treated dams presented neurologic effects. The US study realized at the 5th,6thand th weeks of gestation, showed that ali the experimental groups presented significant reduction of the fetal intrauterine moviments. Hematologic and serum blood biochemical alterations (Iike increased levels of glucose, aspartate-amine transferase, urea, alkaline phosphatase, albumine and reduced levels of gamma-glutamyl transferase and cholesterol) were observed in goats of the experimental groups. The histopathologic study showed vacuolization in several tissues (liver,kidneys and brain). At the 10thweek of gestation one goat, treated with the increased dose, aborted a fetus. This fetus presented arthrogriposis and no closure of the abdominal cavity.At parturition(PND01) fetal malformationswere observed and characterized as retrognatia, multiple congenit contracture of the members and arthrogriposis. The present data showed that I. Carnea ingestion by pregnant goats promoted maternal toxicityand fetal teratogenic effects. In addition, the US showed to be an important tool to monitorize the toxic effects promoted by the plant ingestion during intrauterine life.
13

The synthesis of branched sugars and iminosugars

Parry, Loren L. January 2011 (has links)
Iminosugars, carbohydrate analogues in which nitrogen replaces the endocyclic oxygen, have attracted much interest due to their biological activity. Iminosugars inhibit carbohydrate-processing enzymes, thereby affecting many biological processes. Several iminosugars are licensed drugs, with many more compounds undergoing clinical trials. The main subject of this thesis is the synthesis and evaluation of novel iminosugars, particularly the effects of structural modifications on the biological activity of these compounds. Chapter 1 describes the role of carbohydrate-processing enzymes in the body, and explores the therapeutic applications of iminosugars that arise from their activity against these enzymes. Examples of substituted iminosugars are reviewed, and the effects of substituents on enzyme inhibition are described. Chapter 2 concerns methyl-branched swainsonine derivatives. Swainsonine has shown potential as a cancer treatment through its inhibition of &alpha;-mannosidase. The synthesis of (6R)- and (6S)-C-methyl D-swainsonine is described; both compounds were potent and selective &alpha;-mannosidase inhibitors (IC<sub>50</sub> 3.8 &mu;M, 14 &mu;M). Although less active than the parent compound, their selectivity for Golgi mannosidase over lysosomal mannosidase may be more important than the absolute value against the model enzyme. Chapter 3 describes the synthesis of a 2-C-methyl L-fucose derivative. A diastereoselective Kiliani reaction allowed the formation of a single lactone bearing a new quaternary centre. The utility of this intermediate in accessing di-branched iminosugars was explored; however, attempts to introduce nitrogen to the lactone lacked the necessary stereoselectivity. Chapter 4 relates to the synthesis of pyrrolidine iminosugars, specifically methyl amides. Two enantiomeric dihydroxyproline amides were synthesised; the D-proline derivative was a potent &beta;-N-acetylhexosaminidase inhibitor (IC<sub>50</sub> values of up to 3.6 &mu;M), but the L-enantiomer was completely inactive. Inhibition of N-acetylhexosaminidases is relevant to the treatment of cancer and lysosomal storage diseases, and this work contributed to a wider project investigating the effects of altered stereochemistry on the biological activity of pyrrolidine amides.
14

Doen?a do armazenamento lisossomal causada pela ingest?o espont?nea de Sida carpinifolia em cervos Sambar (Cervus unicolor) cativos no Rio de Janeiro. / Lysosomal storage disease caused by spontaneous ingestion of Sida carpinifolia in captive-Sambar deer (Cervus unicolor) in Rio de Janeiro State, Brazil.

Anjos, Bruno Leite dos 17 August 2010 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2018-04-11T13:17:41Z No. of bitstreams: 1 2010 - Bruno Leite dos Anjos.pdf: 12893665 bytes, checksum: 99b4dd0f8ecdebb1f227aa0522ac061f (MD5) / Made available in DSpace on 2018-04-11T13:17:42Z (GMT). No. of bitstreams: 1 2010 - Bruno Leite dos Anjos.pdf: 12893665 bytes, checksum: 99b4dd0f8ecdebb1f227aa0522ac061f (MD5) Previous issue date: 2010-08-17 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil. / Cases of diseases induced by toxic plants in domestic herbivores are well reported throughout the world and have been studied also in Brazil. However, not much is known about the epidemiological and pathological aspectos of these conditions in free-living wildlife or bred in captivity. The risk for developing the toxicoses in captivity has been increasing, since natural habitats are destroyed by human action, and more centers of wildlife conservation and zoological comes are created. This study describes the epidemiological, biological and clinicopathological, lectin-histochemical and ultrastructural aspects of an outbreak of lysosomal storage disease of oligosaccharides induced by ingestion of Sida carpinifolia in young Sambar deer (Cervus unicolor) in the Rio-Zoo Foundation in the State of Rio de Janeiro, Brazil. Nine deer showed neurological signs characterized by motor and proprioceptive deficits. Then neurological signs were mainly depression, incoordination, dysmetria, ataxia, broad-based members, muscle tremors, loss of tongue tone, frequent falls and death. Grossly hematomas were observed secondary to trauma caused by dominant males of the flock, and whitish striations, especially in the renal cortex. Histologic changes included marked swelling/cytoplasmic vacuolization especially in neurons, progressing to neuronal lysis and axonal spheroids, in exocrine pancreas, thyroid follicular cells and renal tubular epithelial cells. In the lectin-histochemical examination the vacuoles were formed by the accumulation of oligosaccharides specially marked by the lectins WGA, WGA and Con-A. Ultrastructurally, the swelling/vacuolation corresponded to intense cytoplasmic distention of lysosomes, formation of residual bodies or dense granular fragments of membranes and mielinoides bodies. The study has shown the susceptibility of Cervus unicolor to swainsonine by ingestion of S. carpinifolia. Possibly poisoning the animals in this study was conducted by food restriction by the hierarchy among males in the group. It might also determine the marked similarity between clinical and pathological aspects in Sambar deer with the one presented by other herbivores. / Casos de doen?as induzidas por plantas t?xicas em herb?voros dom?sticos s?o bastante relatados por todo o mundo e v?m sendo estudados tamb?m no Brasil. Pouco se sabe, contudo, sobre os aspectos epidemiol?gicos e patol?gicos dessas condi??es em animais selvagens de vida livre ou criados em cativeiro. Os riscos de desenvolvimento dessas toxicoses em cativeiros v?m aumentando, conforme os habitats naturais s?o destru?dos pela a??o humana, e mais centros de conserva??o de vida silvestre e zool?gicos s?o criados. Nesse estudo s?o descritos os aspectos epidemiol?gicos, biol?gicos e clinicopatol?gicos, lectinohistoqu?micos e ultraestruturais de um surto de doen?a do armazenamento lisossomal de oligossacar?deos induzido pela ingest?o de Sida carpinifolia em cervos Sambar jovens (Cervus unicolor) no zool?gico da Funda??o Rio-Zoo no Estado do Rio de Janeiro. Nove cervos apresentaram sinais cl?nicos neurol?gicos caracterizados por d?ficits proprioceptivo e motor. Os sinais neurol?gicos inclu?ram principalmente depress?o, incoordena??o, dismetria, ataxia, membros em base ampla, tremores musculares, perda do t?nus lingual, quedas frequentes e morte. Macroscopicamente foram observados hematomas, secund?rios a traumas provocados por machos dominantes do rebanho, e estria??es esbranqui?adas, principalmente no c?rtex renal. As les?es histol?gicas inclu?am acentuada tumefa??o/vacuoliza??o citoplasm?tica especialmente em neur?nios, p?ncreas ex?crino, c?lulas foliculares da tireoides e do epit?lio renal, necrose neuronal com evolu??o para lise e esferoides axonais. Pelo exame lectino-histoqu?mico os vac?olos eram formados por ac?mulo de oligossacar?deos marcado especialmente pelas lectinas S-WGA, WGA e Con-A. Ultraestruturalmente, a tumefa??o/vacuoliza??o citoplasm?tica correspondeu ? intensa distens?o de lisossomos, forma??o de corpos residuais densos ou granulares, fragmentos de membranas e corpos mielinoides. O estudo demonstrou a suscetibilidade de Cervus unicolor ? swainsonina contida na S. carpinifolia. Possivelmente, a intoxica??o nos animais deste estudo ocorreu pela restri??o alimentar sofrida pelos animais mais jovens, decorrente da hierarquia entre machos no grupo. P?de-se determinar ainda a marcada similaridade do quadro cl?nico e patol?gico entre os cervos descritos nesse trabalho e outros herb?voros dom?sticos.

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