The role of hyperthermia during regional alkylating agent chemotherapy is controversial. The aim of this study was to determine the exact contribution of hyperthermia to tumor response during isolated limb infusion with l-phenylalanine mustard. Rats bearing rodent fibrosarcoma on the hindlimb underwent isolated limb infusion with saline, saline plus heat, l-phenylalanine mustard, l-phenylalanin...

Calculation of rates of protein synthesis, based upon incorporation of [14C]phenylalanine into protein, depended upon use of the specific activity of phenylalanyl-tRNA. At a perfusate phenylalanine concentration of 0.01 mM, the specific activity of phenylalanyl-tRNA was 65 and 155% of extracellular and intracellular specific activities, respectively. At this concentration, the rate of protein s...

Phenylalanine ammonia-lyase, which irreversibly deaminates phenylalanine and tyrosine, markedly inhibited the growth of human leukemic and murine L5178Y lymphoblasts in vitro but had a negligible effect on resting (nondividing) normal lymphocytes. These studies also demonstrated that phenylalanine ammonia-lyase inhibited DNA synthesis in leukemic cells at least as effectively as did asparaginas...

Self-assembly of phenylalanine is linked to amyloid formation toxicity in phenylketonuria disease. We are demonstrating that L-phenylalanine self-assembles to amyloid fibrils at varying experimental conditions and transforms to a gel state at saturated concentration. Biophysical methods including nuclear magnetic resonance, resistance by alpha-phenylglycine to fibril formation and preference of...

Phenylketonuria is the most prevalent disorder caused by an inborn error in aminoacid metabolism. It results from mutations in the phenylalanine hydroxylase gene. Phenotypes can vary from a very mild increase in blood phenylalanine concentrations to a severe classic phenotype with pronounced hyperphenylalaninaemia, which, if untreated, results in profound and irreversible mental disability. Neo...

Phenylalanine ammonia-lyase, which irreversibly deaminates phenylalanine and tyrosine, markedly inhibited the growth of human leukemic and murine L5178Y lymphoblasts in vitro but had a negligible effect on resting (nondividing) normal lymphocytes. These studies also demonstrated that phenylalanine ammonia-lyase inhibited DNA synthesis in leukemic cells at least as effectively as did asparaginas...

The M4 isozyme of lactate dehydrogenase was purified to homogeneity from normal rat liver and from two Morris hepatomas (7777 and 7793). Amino-terminal analyses with fluorodinitrobenzene failed to detect the presence of free amino-terminal residues in each enzyme studied. Each enzyme contained between 3.7 and 4.1 moles of protein-bound acetyl groups per mole of enzyme. The amino-terminal peptid...

This case describes a 50-yr-old man who was admitted to the Urology Ward upon the suspicion of a left kidney tumor. As part of the pre-operative check-up, an ultrasound and computed tomography of the kidneys were conducted. The results confirmed the initial diagnosis. The postoperative diagnosis was extra-adrenal pararenal phaeochromocytoma (ePCC) with succinate dehydrogenase complex, subunit B...

A full-length human phenylalanine hydroxylase cDNA has been recombined with a prokaryotic expression vector and introduced into Escherichia coli. Transformed bacteria express phenylalanine hydroxylase immunoreactive protein and pterin-dependent conversion of phenylalanine to tyrosine. Recombinant human phenylalanine hydroxylase produced in E. coli has been partially purified, and biochemical st...