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Screening for Biopterin Disorders in PKU
Pediatrics, 1980It is now recognized (Pediatrics 65:806, 1980) that a small proportion of cases of phenylketonuria (PKU) may be due to abnormalities in the metabolism of biopterin. These cases do not respond to the restriction of dietary phenylalanine, but may be benefited by neurotransmitter replacement therapy. A specific diagnosis is therefore desirable.
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Cytotoxicity of 6-Biopterin to Human Melanocytes
Biochemical and Biophysical Research Communications, 1994(6R)5,6,7,8 tetrahydrobiopterin (6-BH4) is an important cofactor in the regulation of melanogenesis in melanocytes, where it controls: (a) the supply of L-tyrosine from L-phenylalanine via phenylalanine hydroxylase, and (b) regulates directly dopaquinone formation from L-tyrosine via tyrosinase.
John M. Wood +5 more
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Biopterin metabolism in patients with malignant syndrome
Parkinsonism & Related Disorders, 2003We examined the autopsied brains of two parkinsonian patients who had malignant syndrome (MS). Neopterin and biopterin contents, and GTP cyclohydrolase I activity were measured in various region of the brain. We found relatively higher GTP cyclohydrolase I activities in the hypothalamus compared with other regions of the brain from patients with MS ...
H. Ichinose +7 more
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Biopterin cofactor and monoamine-synthesizing monooxygenases
Neurochemistry International, 1983The activities of three pterin-requiring monooxygenases, phenylalanine hydroxylase, tyrosine hydroxylase and tryptophan hydroxylase, are regulated by the level of the pterin cofactor, (6R)- l -erythro- tetrahydrobiopterin , which is synthesized from guanosine triphosphate (GTP).
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Neurochemical Research, 1976
Intraperitoneally injected [(14)C]biopterin (B), dihydrobiopterin (BH2), and tetrahydrobiopterin (BH4) penetrated the brain rapidly, but in amounts sufficient to represent only a minor source of supply. Unlike isobiopterin, B was rapidly reduced to BH2 in brain.
Gál Em, Hanson G, Sherman A
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Intraperitoneally injected [(14)C]biopterin (B), dihydrobiopterin (BH2), and tetrahydrobiopterin (BH4) penetrated the brain rapidly, but in amounts sufficient to represent only a minor source of supply. Unlike isobiopterin, B was rapidly reduced to BH2 in brain.
Gál Em, Hanson G, Sherman A
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Synthesis of biopterin and related pterin glycosides
IUBMB Life, 2013AbstractCertain pterins having a hydroxyalkyl side chain at C‐6 have been found as glycosidic forms in certain prokaryotes, such as 2′‐O‐(α‐D‐glucopyranosyl)biopterin from various kinds of cyanobacteria, and limipterin from a green sulfur photosynthetic bacterium.
Hiroshi Yamamoto, Tadashi Hanaya
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Plasma biopterin levels and tetrahydrobiopterin responsiveness
Molecular Genetics and Metabolism, 2005Tetrahydrobiopterin (BH4) responsive hyperphenylalaninemia (HPA) with a mutant phenylalanine hydroxylase (PAH) gene was found during neonatal screening for PKU. This study determined blood BH4 and phenylalanine in two patients with hyperphenylalaninemia following oral load with BH4 10 mg/kg. Our patients underwent neonatal screening for PKU, had normal
Minoru Asada +4 more
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Diastereomers of Neopterin and Biopterin in Human Urine
Biological Chemistry Hoppe-Seyler, 1992A new pteridine compound, named umanopterin, was isolated from human urine both of cancer patients and non-cancer controls. The structure was confirmed to be 2-amino-4(3H)-oxo-6-[(1'R,2'R)-1',2',3'-trihydroxypropyl]pteridine , a diastereomer of neopterin.
Keisuke Fujita +4 more
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Hyperphenylalaninaemia caused by defects in biopterin metabolism
Journal of Inherited Metabolic Disease, 1985AbstractThe hepatic phenylalanine hydroxylating system consists of three essential components, phenylalanine hydroxylase, dihydropteridine reductase and the non‐protein coenzyme, tetrahydrobiopterin. The reductase and the pterin coenzyme are also essential components of the tyrosine and tryptophan hydroxylating systems.
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Life Sciences, 1984
Levels of GTP cyclohydrolase, neopterin and biopterin were determined in tissues and body fluids of humans, monkey, dog and mouse. Highest levels of GTP cyclohydrolase and biopterin were found in pineal, liver, spleen, bone marrow, whole adrenal gland and small intestine. High levels of biopterin were found in the urine of all species examined.
David S. Duch +3 more
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Levels of GTP cyclohydrolase, neopterin and biopterin were determined in tissues and body fluids of humans, monkey, dog and mouse. Highest levels of GTP cyclohydrolase and biopterin were found in pineal, liver, spleen, bone marrow, whole adrenal gland and small intestine. High levels of biopterin were found in the urine of all species examined.
David S. Duch +3 more
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