Results 261 to 270 of about 25,647 (343)

Silk Hydrogels with Controllable Formation of Dityrosine, 3,4-Dihydroxyphenylalanine, and 3,4-Dihydroxyphenylalanine-Fe3+ Complexes through Chitosan Particle-Assisted Fenton Reactions.

Biomacromolecules, 2021
The oxidation of tyrosine residues of silk fibroin involves the generation of dityrosine and 3,4-dihydroxyphenylalanine (DOPA). However, it remains a challenge to selectively control the reaction pathway to produce dityrosine or DOPA in a selective ...
Jaewon Choi, Onur Hasturk, X. Mu, J. Sahoo, D. Kaplan   +4 more
semanticscholar   +1 more source

Dihydroxyphenylalanine in Extrapyramidal Disease

JAMA: The Journal of the American Medical Association, 1963
EVIDENCE has been accumulating for the past several years which has implicated dopamine metabolism in the production of extrapyramidal symptoms. Drugs such as reserpine which tend to produce extrapyramidal symptoms as a side effect have been shown to deplete dopamine from the brain.
A J, FRIEDHOFF, L, HEKIMIAN, M, ALPERT, E, TOBACH   +3 more
openaire   +2 more sources

Efficient Synthesis of Hydroxytyrosol from l-3,4-Dihydroxyphenylalanine Using Engineered Escherichia coli Whole Cells.

Journal of Agricultural and Food Chemistry, 2019
Hydroxytyrosol is a high-value-added compound with a variety of biological and pharmacological activities. In this study, a whole-cell catalytic method for the synthesis of hydroxytyrosol was developed: aromatic amino acid aminotransferase (TyrB), l ...
Chao-Jun Li, Pu Jia, Yajun Bai, T. Fan, Xiaohui Zheng, Yujie Cai   +5 more
semanticscholar   +1 more source

Neuronal Source of Plasma Dihydroxyphenylalanine

The Journal of Clinical Endocrinology & Metabolism, 1987
The source and significance of plasma levels of dihydroxyphenylalanine (DOPA), the precursor of the endogenous catecholamines, have been unknown. We measured arterial and venous plasma DOPA concentrations in healthy subjects at rest, patients who had undergone regional sympathectomies or were undergoing general anesthesia, and subjects during ...
DAVID S. GOLDSTEIN, ROBERT UDELSMAN, GRAEME EISENHOFER, ROBIN STULL, HARRY R. KEISER, IRWIN J. KOPIN, CAROL JOAN FOLIO   +6 more
openaire   +2 more sources

Self-Powered Enzymatic Electrosynthesis of l-3,4-Dihydroxyphenylalanine in a Hybrid Bioelectrochemical System

ACS Sustainable Chemistry and Engineering, 2018
Enzymatic electrosynthesis has been used to synthesize a variety of chemicals with the electric energy input.
R. Wu, Zhiguang Zhu
semanticscholar   +1 more source

Decarboxylation of 3,4-dihydroxyphenylalanine by oxyhemoglobin

Biochemical and Biophysical Research Communications, 1972
Abstract A lysate of red blood cells catalyzes the decarboxylation of 3,4-dihydroxyphenylalanine. This activity appears to be due to a reaction with oxyhemoglobin and not the presence of aromatic L amino acid decarboxylase in erythrocytes.
H, Yamabe, W, Lovenberg
openaire   +2 more sources

Dihydroxyphenylalanine secretion in a malignant pheochromocytoma

The American Journal of Medicine, 1967
Abstract Studies on catecholamine metabolism in patients with neural crest tumors revealed a high plasma level of 3,4-dihydroxyphenylalanine (dopa) and dopamine (DM) in association with a malignant, but not a benign pheochromocytoma. The large amounts of these amines may have been mistaken in other studies for norepinephrine because of the use of a ...
A H, Anton, M, Greer, D F, Sayre, C M, Williams   +3 more
openaire   +2 more sources

Syntheses of α-ethynyl-3, 4-dihydroxyphenylalanine and α-vinyl-3, 4-dihydroxyphenylalanine

Tetrahedron Letters, 1977
3,4-Dihydroxy-benzoesaureester (I) liefert mit Diphenyldichlormethan den cyclischen Ester (II), der nach Reduktion zum Carbinol (IIIa) ein Benzylchlorid (IIIb) gibt, das mit dem Acetylen-imin (IV) zu einem Substitutionsprodukt (V) fuhrt.
D. Taub, A.A. Patchett
openaire   +1 more source

3, 4-Dihydroxyphenylalanine and Related Compounds

1966
This review covers essentially derivatives of β-phenyl-α-alanine which contain two phenolic hydroxyl groups, and some of their analogs and derivatives. They comprise β-(3, 4-dihydroxyphenyl)-α-alanine (dopa) and the few known ethers and ring substituted derivatives of this amino acid, as well as derivatives of dopa substituted in the alanine group ...
A R, Patel, A, Burger
openaire   +2 more sources

Origin and Significance of Plasma Dihydroxyphenylalanine

1997
Publisher Summary This chapter summarizes the origin and the significance of plasma 3,4-Dihydroxyphenylalanine (DOPA). DOPA is both a catecholamine and an aromatic amino acid. DOPA occupies a central position in the function of the sympathetic nervous system. It is the immediate product of the rate-limiting step in the biosynthesis of catecholamines:
Eldrup, Ebbe, Richter, Erik A., Hetland, Merete L., Andreasen, Jan, Hilsted, Jannik, Møller, Svend E., Christensen, Niels Juel   +6 more
openaire   +2 more sources