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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.
1

Porfiria aguda intermitente: estudo clínico de 37 casos. / Acute intermittent porphyria: clinical study of 37 cases.

Puglia, Paula Marzorati Kuntz 20 April 2001 (has links)
A porfiria aguda intermitente é uma doença autossômica dominante, decorrente de um distúrbio na via biossintética do heme, causado pela redução dos níveis da enzima uroporfirinogênio-I-sintetase. As manifestações clínicas envolvem o sistema nervoso periférico e o central. O diagnóstico baseia-se na excreção urinária elevada dos precursores das porfirinas ácido d-aminolevulínico e porfobilinogênio. O objetivo deste estudo foi analisar o quadro clínico apresentado por pacientes do Hospital das Clínicas de São Paulo com porfiria aguda intermitente, atendidos no período de janeiro de 1979 a dezembro de 1999. Foram avaliados 37 pacientes, com idades entre 6 e 48 anos, na proporção de 2,7 mulheres:1 homem. A faixa etária na qual ocorreu o maior número de crises foi a terceira década. Os pacientes apresentaram 63 crises, sendo que 13 deles também tiveram manifestações de caráter crônico. As manifestações clínicas mais freqüentes foram: dor abdominal, alteração da cor da urina, mudança no ritmo intestinal, déficit motor ou sensitivo-motor, vômitos, alteração do nível de consciência ou confusão mental, crises convulsivas, quadros disautonômicos cardio-vasculares e distúrbios psiquiátricos. As crises foram classificadas em leves, moderadas e graves, segundo critérios previamente estabelecidos. Todas as manifestações crônicas foram caracterizadas como leves. A neuropatia periférica motora ou sensitivo-motora nunca foi a manifestação inicial da crise de porfiria aguda intermitente. Houve correlação entre o tipo e o número de fatores precipitantes e a manifestação da neuropatia periférica motora ou sensitivo-motora, verificando-se que as crises nas quais ela está ausente foram em geral desencadeadas por apenas um fator, mais comumente de origem endócrina ou metabólica endógena, como período menstrual e jejum, enquanto que nas crises com neuropatia periférica houve a participação de vários fatores concomitantemente, sendo estes principalmente de origem exógena, como medicamentos. Os tratamentos mais utilizados nos surtos foram a administração de glicose, aumento da ingestão de carboidratos e o uso de fenotiazínicos. / Acute intermittent porphyria is an autosomal dominant disease, caused by a disturbance in the heme biosynthetic pathway, secondary to the reduction on the levels of uroporphyrinogen-I-synthetase enzyme. Clinical manifestations involve central and peripheral nervous system. The diagnosis is based on the elevated urinary excretion of porphyrins precursors d-aminolevulinic acid and porphobilinogen. The aim of this study was to analyze the clinical manifestations of acute intermittent porphyria in patients of the Hospital das Clínicas of São Paulo, seen between January 1979 and December 1999. 37 patients were studied, from 6 to 48 years old, with a rate of 2,7 women: 1 man. The age in which most of the crisis occurred was the third decade. The patients presented 63 crisis, and 13 of them presented also with chronic manifestations. The commonest clinical presentations were: abdominal pain, change in urine color, change in bowel habits, motor or sensory-motor deficit, vomiting, alteration of consciousness or mental confusion, convulsions, dysautonomic cardiovascular signs and psychiatric disorders. The crisis were classified as mild, moderate and severe, following criteria previously established. All chronic manifestations were characterized as mild. The peripheral motor or sensory-motor neuropathy was never the initial manifestation. Correlation was found between the kind and the number of precipitating factors, and the absence of peripheral neuropathy was in general related to just one factor, more commonly of endogenous endocrine or metabolic origin, like menstrual period and starvation, while in the crisis with peripheral neuropathy multiple factors were involved at the same time, these being of exogenous origin, like drugs. The most commonly used treatments were glucose administration, elevation of carbohydrate intake, and phenothiazines use.
2

Molekulární patologie vybraných porfyrií s kožní manifestací / Molecular pathology of selected porphyria with skin manifestation

Sameh Anwar Hussein Farrag, Mohamed January 2015 (has links)
Porphyria is a group of inherited metabolic disorders due to enzymatic defect of the heme biosynthesis resulting in the overproduction of the heme precursors' porphyrins in different body organs. The enzymes of the heme biosynthesis are encoded by corresponding genes in which any defect in any of these genes lead to a specific type of porphyria. Numerous mutations were detected in these genes leading to impairment in the enzyme function and therefore developing of the clinical manifestations of porphyria. The aim of the present work was to investigate the UROD gene in patients with porphyria cutanea tarda (PCT) and hepatoerythropoietic protoporphyria (HEP) as well as the FECH gene in patients with erythropoietic protoporphyria (EPP) on a molecular level. We identified numerous mutations in the FECH and the UROD genes in three different populations, Czech, Slovak, and Egyptian. We described the novel mutations in the UROD gene in HEP Arabic patients from Egypt as well in the FECH gene in patients with EPP of Czech and Slovak origin. We expressed mutatted UROD protein in prokaryotic system and found 19 % of the wild-type enzymatic activity. Moreover, the current study presents for the first time the frequency of the low expression allele IVS3-48c in the FECH gene in healthy controls from the Czech...
3

Porfiria aguda intermitente: estudo clínico de 37 casos. / Acute intermittent porphyria: clinical study of 37 cases.

Paula Marzorati Kuntz Puglia 20 April 2001 (has links)
A porfiria aguda intermitente é uma doença autossômica dominante, decorrente de um distúrbio na via biossintética do heme, causado pela redução dos níveis da enzima uroporfirinogênio-I-sintetase. As manifestações clínicas envolvem o sistema nervoso periférico e o central. O diagnóstico baseia-se na excreção urinária elevada dos precursores das porfirinas ácido d-aminolevulínico e porfobilinogênio. O objetivo deste estudo foi analisar o quadro clínico apresentado por pacientes do Hospital das Clínicas de São Paulo com porfiria aguda intermitente, atendidos no período de janeiro de 1979 a dezembro de 1999. Foram avaliados 37 pacientes, com idades entre 6 e 48 anos, na proporção de 2,7 mulheres:1 homem. A faixa etária na qual ocorreu o maior número de crises foi a terceira década. Os pacientes apresentaram 63 crises, sendo que 13 deles também tiveram manifestações de caráter crônico. As manifestações clínicas mais freqüentes foram: dor abdominal, alteração da cor da urina, mudança no ritmo intestinal, déficit motor ou sensitivo-motor, vômitos, alteração do nível de consciência ou confusão mental, crises convulsivas, quadros disautonômicos cardio-vasculares e distúrbios psiquiátricos. As crises foram classificadas em leves, moderadas e graves, segundo critérios previamente estabelecidos. Todas as manifestações crônicas foram caracterizadas como leves. A neuropatia periférica motora ou sensitivo-motora nunca foi a manifestação inicial da crise de porfiria aguda intermitente. Houve correlação entre o tipo e o número de fatores precipitantes e a manifestação da neuropatia periférica motora ou sensitivo-motora, verificando-se que as crises nas quais ela está ausente foram em geral desencadeadas por apenas um fator, mais comumente de origem endócrina ou metabólica endógena, como período menstrual e jejum, enquanto que nas crises com neuropatia periférica houve a participação de vários fatores concomitantemente, sendo estes principalmente de origem exógena, como medicamentos. Os tratamentos mais utilizados nos surtos foram a administração de glicose, aumento da ingestão de carboidratos e o uso de fenotiazínicos. / Acute intermittent porphyria is an autosomal dominant disease, caused by a disturbance in the heme biosynthetic pathway, secondary to the reduction on the levels of uroporphyrinogen-I-synthetase enzyme. Clinical manifestations involve central and peripheral nervous system. The diagnosis is based on the elevated urinary excretion of porphyrins precursors d-aminolevulinic acid and porphobilinogen. The aim of this study was to analyze the clinical manifestations of acute intermittent porphyria in patients of the Hospital das Clínicas of São Paulo, seen between January 1979 and December 1999. 37 patients were studied, from 6 to 48 years old, with a rate of 2,7 women: 1 man. The age in which most of the crisis occurred was the third decade. The patients presented 63 crisis, and 13 of them presented also with chronic manifestations. The commonest clinical presentations were: abdominal pain, change in urine color, change in bowel habits, motor or sensory-motor deficit, vomiting, alteration of consciousness or mental confusion, convulsions, dysautonomic cardiovascular signs and psychiatric disorders. The crisis were classified as mild, moderate and severe, following criteria previously established. All chronic manifestations were characterized as mild. The peripheral motor or sensory-motor neuropathy was never the initial manifestation. Correlation was found between the kind and the number of precipitating factors, and the absence of peripheral neuropathy was in general related to just one factor, more commonly of endogenous endocrine or metabolic origin, like menstrual period and starvation, while in the crisis with peripheral neuropathy multiple factors were involved at the same time, these being of exogenous origin, like drugs. The most commonly used treatments were glucose administration, elevation of carbohydrate intake, and phenothiazines use.
4

Molekulární patologie vybraných porfyrií s kožní manifestací / Molecular pathology of selected porphyria with skin manifestation

Sameh Anwar Hussein Farrag, Mohamed January 2015 (has links)
Porphyria is a group of inherited metabolic disorders due to enzymatic defect of the heme biosynthesis resulting in the overproduction of the heme precursors' porphyrins in different body organs. The enzymes of the heme biosynthesis are encoded by corresponding genes in which any defect in any of these genes lead to a specific type of porphyria. Numerous mutations were detected in these genes leading to impairment in the enzyme function and therefore developing of the clinical manifestations of porphyria. The aim of the present work was to investigate the UROD gene in patients with porphyria cutanea tarda (PCT) and hepatoerythropoietic protoporphyria (HEP) as well as the FECH gene in patients with erythropoietic protoporphyria (EPP) on a molecular level. We identified numerous mutations in the FECH and the UROD genes in three different populations, Czech, Slovak, and Egyptian. We described the novel mutations in the UROD gene in HEP Arabic patients from Egypt as well in the FECH gene in patients with EPP of Czech and Slovak origin. We expressed mutatted UROD protein in prokaryotic system and found 19 % of the wild-type enzymatic activity. Moreover, the current study presents for the first time the frequency of the low expression allele IVS3-48c in the FECH gene in healthy controls from the Czech...
5

5-Aminolevulinic acid and derivatives thereof : properties, lipid permeability and enzymatic reactions

Erdtman, Edvin January 2010 (has links)
5-aminolevulinic acid (5-ALA) and derivatives thereof are widely usedprodrugs in treatment of pre-malignant skin diseases of the cancer treatmentmethod photodynamic therapy (PDT). The target molecule in 5-ALAPDTis protoporphyrin IX (PpIX), which is synthesized endogenously from5-ALA via the heme pathway in the cell. This thesis is focused on 5-ALA,which is studied in different perspectives and with a variety of computationalmethods. The structural and energetic properties of 5-ALA, itsmethyl-, ethyl- and hexyl esters, four different 5-ALA enols, and hydrated5-ALA have been investigated using Quantum Mechanical (QM) first principlesdensity functional theory (DFT) calculations. 5-ALA is found to bemore stable than its isomers and the hydrolysations of the esters are morespontaneous for longer 5-ALA ester chains than shorter. The keto-enoltautomerization mechanism of 5-ALA has been studied, and a self-catalysismechanism has been proposed to be the most probable. Molecular Dynamics(MD) simulations of a lipid bilayer have been performed to study themembrane permeability of 5-ALA and its esters. The methyl ester of 5-ALAwas found to have the highest permeability constant (PMe-5-ALA = 52.8 cm/s).The mechanism of the two heme pathway enzymes; Porphobilinogen synthase(PBGS) and Uroporphyrinogen III decarboxylase (UROD), have beenstudied by DFT calculations and QM/MM methodology. The rate-limitingstep is found to have a barrier of 19.4 kcal/mol for PBGS and 13.7kcal/mol for the first decarboxylation step in UROD. Generally, the resultsare in good agreement with experimental results available to date.
6

Investigating the porphyrias through analysis of biochemical pathways.

Ruegg, Evonne Teresa Nicole January 2014 (has links)
ABSTRACT The porphyrias are a diverse group of metabolic disorders arising from diminished activity of enzymes in the heme biosynthetic pathway. They can present with acute neurovisceral symptoms, cutaneous symptoms, or both. The complexity of these disorders is demonstrated by the fact that some acute porphyria patients with the underlying genetic defect(s) are latent and asymptomatic while others present with severe symptoms. This indicates that there is at least one other risk factor required in addition to the genetic defect for symptom manifestation. A systematic review of the heme biosynthetic pathway highlighted the involvement of a number of micronutrient cofactors. An exhaustive review of the medical literature uncovered numerous reports of micronutrient deficiencies in the porphyrias as well as successful case reports of treatments with micronutrients. Many micronutrient deficiencies present with symptoms similar to those in porphyria, in particular vitamin B6. It is hypothesized that a vitamin B6 deficiency and related micronutrient deficiencies may play a major role in the pathogenesis of the acute porphyrias. In order to further investigate the porphyrias, a computational model of the heme biosynthetic pathway was developed based on kinetic parameters derived from a careful analysis of the literature. This model demonstrated aspects of normal heme biosynthesis and illustrated some of the disordered biochemistry of acute intermittent porphyria (AIP). The testing of this model highlighted the modifications necessary to develop a more comprehensive model with the potential to investigated hypotheses of the disordered biochemistry of the porphyrias as well as the discovery of new methods of treatment and symptom control. It is concluded that vitamin B6 deficiency might be the risk factor necessary in conjunction with the genetic defect to trigger porphyria symptoms.

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