Few studies have looked at optimal or acceptable serum phenylalanine levels in later life in patients with phenylketonuria (PKU). This study examined the oxidative stress status of adolescents and adults with PKU. Forty PKU patients aged over fifteen years were enrolled, and were compared with thirty age-matched controls. Oxidative stress markers, anti-oxidant enzyme activities in erythrocytes,...

Muscle protein synthesis in dogs measured by flooding with L-[(2)H(5)]phenylalanine (70 mg/kg) was significantly stimulated by infusion of insulin with amino acids. The stimulation of muscle protein synthesis was similar when calculated from the enrichment of phenylalanyl-tRNA (61 +/- 10%, P < 0.001), plasma phenylalanine (61 +/- 10%, P < 0.001), or tissue fluid phenylalanine (54 +/- 10%, P < 0...

Phenylalanine has previously been resolved by fractional crystallization of the brucine salt of formyl-nn-phenylalanine (1) or of the cinchonine salt of benzoyl-nn-phenylalanine (2). Enzymatic methods have also been used for the resolution. According to the method of Gilbert, Price, and Greenstein (3), racemic phenylalanine is resolved by subjecting its Nchloroacetylated derivative to asymmetri...

phenylketonuria (pku) is an inborn error of amino acid metabolism with an autosomal recessive inheritance caused in most cases by mutations in the phenylalanine hydroxylase (pah) gene. pku has wide allelic heterogeneity. here we report a novel heterozygous substitution (c.1223g>t (p.arg408leu)) in the pah gene in an iranian pku family. the patient was 19-yr-old female with diagnosis of moderate...

background: the haplotype phasing is more useful than genotyping markers independently at carrier detection and prena­tal diagnosis of diseases. the pah gene region contains several markers used in detection of pku disease. in the present study, the efficiency of bgl ii- ecor i-vntr haplotype phasing in iranian family trios was investigated. then, this informa­tion was compared with those obtai...

Methods routinely utilized for detection of phenylalanine in new-born blood consist of enzymatic assays, lacking sensitivity and HPLC assays which are expensive and time-consuming to conduct. We, here, report for the first time, the construction of a phenylalanine sensitive electrode, on the basis of a selective molecularly imprinted polymer, offering sensitivity, economy and ease of use for th...

The incorporation of [(14)C]phenylalanine and [1,6-(14)C]shikimic acid into tyrosine was investigated in the callus of Portulaca grandiflora, var. JR (L.). By inhibiting phenylalanine with 1-alpha-aminooxy-beta-phenyl-propionic acid and tyrosinase with 1-cysteine-HCl and hydrazine-hydrate, the possible synthesis of tyrosine from phenylalanine was demonstrated. Tetrahydropterine sulfate was an e...

INTRODUCTION Hyperphenylalaninemias are inborn errors of phenylalanine metabolism caused by deficiency of L-phenylalanine hydroxylase (the enzyme that converts phenylalanine to tyrosine), resulting in increased serum phenylalanine (>4 mg/dL or 240 µmol/L). Phenylketonuria, or PKU, is the most common form. Untreated PKU is associated with progressive neurodevelopmental delay, evolving towards in...

In normal individuals the major portion of ingested phenylalanine is converted into tyrosine. In the disease phenylpyruvic oligophrenia, however, ingested phenylalanine is converted mainly into phenylpyruvic and phenyllactic acids (l), which are excreted in the urine. This phenomenon has been ascribed to the inability of the body to convert phenylalanine to tyrosine (2) and a consequent shuntin...