Results 231 to 240 of about 23,156 (257)
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Tetrahydrobiopterin induced neonatal tyrosinaemia
European Journal of Pediatrics, 1996Sir: Transient neonatal tyrosinaemia is thought to be caused by late maturation of the hepatic enzymes 4-hydroxyphenylpyruvate dioxygenase and tyrosine aminotransferase [4]. In addition to prematurity, high protein intake and ascorbate deficiency are suggested as risk factors [2].
N, Blau, M, Beck, D, Matern
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Tetrahydrobiopterin and Parkinson's disease
Acta Neurologica Scandinavica, 1989Two patients with Parkinson's disease were treated with 1 g tetrahydrobiopterin (BH4) for 5 days. Clinical improvement was not observed. In the cerebrospinal fluid (CSF) a 4-8 fold increase in the concentration of homovanillic acid (HVA), and a 3-fold increase in the concentration of 5-hydroxyindole acetic acid (5-HIAA) was measured.
I C, Dissing +6 more
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Tetrahydrobiopterin: biochemistry and pathophysiology
Biochemical Journal, 2011BH4 (6R-L-erythro-5,6,7,8-tetrahydrobiopterin) is an essential cofactor of a set of enzymes that are of central metabolic importance, including four aromatic amino acid hydroxylases, alkylglycerol mono-oxygenase and three NOS (NO synthase) isoenzymes. Consequently, BH4 is present in probably every cell or tissue of higher organisms and plays a key role
Werner, E R, Blau, N, Thöny, B
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Differential Diagnosis of Tetrahydrobiopterin Deficiency
Journal of Inherited Metabolic Disease, 1985AbstractSix hundred and seventy‐three children (483 newborns and 190 older selected children) were screened for tetrahydrobiopterin (BH4) deficiency by HPLC of urine pterins and BH4 load test. One patient with GTP cyclohydrolase I deficiency, 36 patients with dihydrobiopterin synthetase (DHBS) deficiency (of which six were in the newborn and 30 in the ...
A, Niederwieser +2 more
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Neurological Involvement in Tetrahydrobiopterin Deficiency
Journal of Pediatric Biochemistry, 2016Tetrahydrobiopterin (BH4) is a natural and essential cofactor for the enzymatic hydroxylation of phenylalanine (Phe) and tyrosine (Tyr), and for two tryptophan hydroxylases, three nitric oxide synthases, and glyceryl-ether monooxygenase. Five separate genetic conditions affecting BH4 synthesis or recycling have been identified so far, including ...
Mascaro I +10 more
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The auto‐oxidation of tetrahydrobiopterin
European Journal of Biochemistry, 1988The product of the aerobic oxidation of tetrahydrobiopterin, quinonoid dihydrobiopterin, is unstable and rapidly rearranges to form a 7,8‐dihydropteridine. Kaufman [Kaufman, S. (1967) J. Biol. Chem. 242, 3934–3943] identified the stable product produced in 0.1 M phosphate pH 6.8, as 7,8‐dihydrobiopterin. However, Armarego et al. [Armarego, W. L.
M D, Davis, S, Kaufman, S, Milstien
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International database of tetrahydrobiopterin deficiencies
Journal of Inherited Metabolic Disease, 1995SummaryApproximately 2% of newborns with hyperphenylalaninaemia are deficient in tetrahydrobiopterin. Selective screening must be performed in all instances where hyperphenylalaninaemia is detected by neonatal screening. In the last 20 years, 308 patients with tetrahydrobiopterin deficiencies have been recognized as a result of screening carried out ...
N, Blau, I, Barnes, J L, Dhondt
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Maternal Phenylketonuria and Tetrahydrobiopterin
Pediatrics, 2008Untreated maternal phenylketonuria (PKU) results in a significant occurrence of microcephaly and congenital heart disease in the offspring. Before the documentation of this fact by Lenke and Levy1 in 1980, there was confusion as to the occurrence of these abnormalities.
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Tetrahydrobiopterin Metabolism
1988Tetrahydrobiopterin is the cofactor for the hydroxylation of phenylalanine, tyrosine and tryptophan and is therefore essential for the production of monoamine neurotransmitters. Neopterin, a biosynthetic precusor of tetrahydrobiopterin, and biopterin appear in urine. In normal subjects the urinary neopterin to biopterin ratio has been found to be about
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Tetrahydrobiopterin-(BH4-)Mangelkrankheiten
2014Die Krankheitsgruppe umfasst 6 angeborene Stoffwechselstorungen, die mit einem Tetrahydrobiopterinmangel (BH4-Mangel) entweder aufgrund einer gestorten BH4-Biosynthese oder eines gestorten BH4-Recyclings einhergehen. Tetrahydrobiopterin (BH4) ist ein essenzieller Kofaktor bei der Biosynthese der Neurotransmitter Dopamin und Serotonin und bei der ...
T. Opladen, N. Blau
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