Tetrahydrobiopterin
Mostrando 1-12 de 84 artigos, teses e dissertações.
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1. Metabolic Control in Patients With Phenylketonuria Pre- and Post-Sapropterin Loading Test
Abstract In Portugal, tetrahydrobiopterin (BH4)-responsive patients with phenylketonuria (PKU) are identified using a loading test (LT). Phenylalanine/natural protein (Phe/NP) intake is increased to elevate blood Phe prior to the LT. In a longitudinal retrospective study, the impact of Phe/NP titration post-LT in 58 patients (19.6 + 8.2 years) with PKU durin
J. inborn errors metab. screen.. Publicado em: 28/02/2019
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2. No diabetes mellitus o chá verde melhora o desacoplamento da áxido nítrico sintase renal por restabelecer os valores de tetrahidrobiopterina = : Uncoupling endothelial nitric oxid synthase is ameliorated by green tea in experimental diabetes mellitus by reestablishing tetrahydrobiopterin levels / Uncoupling endothelial nitric oxid synthase is ameliorated by green tea in experimental diabetes mellitus by reestablishing tetrahydrobiopterin levels
No diabetes mellitus (DM), o estresse oxidativo e a redução do óxido nítrico (NO) contribuem para a patogênese da nefropatia diabética. O desacoplamento da NO sintase endotelial (eNOS) faz com que essa sintase produza superóxido ao invés de NO. O objetivo do presente estudo foi investigar o potencial do chá verde (CV) na melhora do desacoplamento da
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 14/06/2012
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3. Hiperfenilalaninemia por deficiência de fenilalanina hidroxilase : avaliação da responsividade ao BH4 em pacientes acompanhados no Serviço de Genética Médica do HCPA e que apresentam controle metabólico adequado
Introdução: Estudos recentes, utilizando vários protocolos, têm demonstrado que pacientes com Hiperfenilalaninemia por deficiência de fenilalanina hidroxilase (HPA-PAH) podem apresentar redução das concentrações plasmáticas de fenilalanina (Phe) mediante a administração de tetrahidrobiopterina (BH4). Objetivo: Determinar, em uma amostra de pacien
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2011
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4. Hiperfenilalaninemia por deficiência de fenilalanina hidroxilase : identificação de indivíduos responsivos à administração de tetrahidrobiopterina por via oral
Introdução: A Hiperfenilalaninemia por deficiência de fenilalanina hidroxilase (HPAPAH) é um erro inato do metabolismo no qual ocorre aumento dos níveis séricos de fenilalanina (Phe). Estudos recentes, realizados em várias populações, demonstraram que pacientes com HPA-PAH podem apresentar redução das concentrações plasmáticas de Phe mediante a
Publicado em: 2010
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5. Nitric oxide: a major determinant of mast cell phenotype and function
Mast cells (MC) are important in the numerous physiological processes of homeostasis and disease. Most notably, MC are critical effectors in the development and exacerbation of allergic disorders. Nitric oxide (NO) is a diatomic radical produced by nitric oxide synthase (NOS), and has pluripotent cell signaling and cytotoxic properties. NO can influence many
Memórias do Instituto Oswaldo Cruz. Publicado em: 2005-03
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6. Participação do oxido nitrico no desenvolvimento da encefalomielite alergica experimental em ratos
Nitric oxide (NO) is a free radical endogenously synthetised by oxidation of one of the guanidinum nitrogen atoms of the aminoacid L-arginine by molecular oxygen. This biosynthesis is catalised by a family of enzimes generically known as nitric oxide synthases (NOS), which can be inhibited by structural analogs of L-arginine having substituent groups at the
Publicado em: 2001
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7. Tetrahydrobiopterin restores endothelial function in hypercholesterolemia.
In hypercholesterolemia, impaired nitric oxide activity has been associated with increased nitric oxide degradation by oxygen radicals. Deficiency of tetrahydrobiopterin, an essential cofactor of nitric oxide synthase, causes both impaired nitric oxide activity and increased oxygen radical formation. In this study we tested whether tetrahydrobiopterin defici
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8. Oxidation of tetrahydrobiopterin leads to uncoupling of endothelial cell nitric oxide synthase in hypertension
Tetrahydrobiopterin is a critical cofactor for the NO synthases, and in its absence these enzymes become “uncoupled,” producing reactive oxygen species (ROSs) rather than NO. In aortas of mice with deoxycorticosterone acetate–salt (DOCA-salt) hypertension, ROS production from NO synthase is markedly increased, and tetrahydrobiopterin oxidation is evide
American Society for Clinical Investigation.
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9. Structural analysis of porcine brain nitric oxide synthase reveals a role for tetrahydrobiopterin and L-arginine in the formation of an SDS-resistant dimer.
Nitric oxide synthases (NOSs), which catalyze the formation of the ubiquitous biological messenger molecule nitric oxide, represent unique cytochrome P-450s, containing reductase and mono-oxygenase domains within one polypeptide and requiring tetrahydrobiopterin as cofactor. To investigate whether tetrahydrobiopterin functions as an allosteric effector of NO
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10. Regulation of nitric oxide synthesis by proinflammatory cytokines in human umbilical vein endothelial cells. Elevations in tetrahydrobiopterin levels enhance endothelial nitric oxide synthase specific activity.
We have examined cytokine regulation of nitric oxide synthase (NOS) in human umbilical vein endothelial cells (HUVEC). 24-h treatment with IFN-gamma (200 U/ml) plus TNF (200 U/ml) or IL-1 beta (5 U/ml) increased NOS activity in HUVEC lysates, measured as conversion of [14C]L-arginine to [14C]L-citrulline. Essentially, all NOS activity in these cells was calc
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11. Tetrahydrobiopterin increases in adrenal medulla and cortex: a factor in the regulation of tyrosine hydroxylase.
Tetrahydrobiopterin, the cofactor for tyrosine hydroxylase and other monooxygenases, is present in tissues at apparent concentrations much less than those necessary to saturate the corresponding enzymes. Reserpine treatment or insulin-induced hypoglycemia in rats produces a statistically significant increase in the tetrahydrobiopterin content of both the adr
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12. Tetrahydrobiopterin metabolism in the temporal lobe of patients dying with senile dementia of Alzheimer type.
There is a defect in tetrahydrobiopterin metabolism in brains from subjects with senile dementia of Alzheimer type compared to age-matched controls. This defect results in lowered total biopterin concentrations in brain. Brains from subjects with senile dementia of Alzheimer type retain their ability to synthesis neopterin and have normal dihydropteridine re