Results 251 to 260 of about 25,575 (276)

Purine nucleoside phosphorylase polymorphism in sheep erythrocytes

Biochemical Genetics, 1977
A polymorphism of purine nucleoside phosphorylase is described in sheep erythrocytes. Two isozymes were distinguished electrophoretically, one with high activity (NP-1) and one with low activity (NP-2). Breeding data suggest that the two isozymes are the product of two codominant alleles, NP1 and NP2.
P. G. Board, J. E. Smith
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Purine Nucleoside Phosphorylase Deficiency: A Mutation Update

Nucleosides, Nucleotides and Nucleic Acids, 2011
Purine nucleoside phosphorylase (PNPase) deficiency is an autosomal recessive disorder affecting purine degradation and salvage pathways. Clinically, patients typically present with severe immunodeficiency, neurological dysfunction, and autoimmunity. Biochemically, PNPase deficiency may be suspected in the presence of hypouricemia.
A. Corrigan, Monica Arenas, Anthony M. Marinaki, Emilia Escuredo, Lynette D. Fairbanks, P. L. C. Walker   +5 more
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Combined immunodeficiency due to purine nucleoside phosphorylase deficiency: Outcome of three patients.

European Journal of Medical Genetics, 2022
Basak Torun, A. Bilgin, D. Orhan, R. Gocmen, Ş. Kılıç, B. Kuşkonmaz, D. Çetinkaya, I. Tezcan, D. Çağdaş   +8 more
semanticscholar   +1 more source

Genetic Variability of Purine Nucleoside Phosphorylase in the Mouse

1984
The inherited human deficiency of purine nucleoside phosphorylase is associated primarily with cellular immune dysfunction1. We have begun to screen for quantitative activity variants of purine nucleoside phosphorylase in Mus musculus in attempts to establish an animal model for the enzyme deficiencies associated with immunodeficiency disease.
Marcia J. Sparling, Trevor Lukey, Fred G. Biddle, Floyd F. Snyder   +3 more
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Chapter 3. Purine Nucleoside Phosphorylase

2007
Purine nucleoside phosphorylase (PNP) catalyzes the reversible phosphorolysis of purine ribonucleosides and 2′-deoxypurine ribonucleosides to the free base, and ribose 1-phosphate or 2′-deoxyribose 1-phosphate, respectively.1–3 PNPs are found in most prokaryotic and eukaryotic organisms where the en...
Steven E. Ealick, Yang Zhang
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Plasma purine nucleoside phosphorylase in cancer patients

Clinica Chimica Acta, 2004
Purine nucleoside phosphorylase (PNP) is the purine salvage enzyme that converts guanosine to guanine and inosine to hypoxanthine.279 samples from patients with differing cancers were collected during treatment at both pre- and post-dose stages for plasma PNP activity and compared with a normal population.Normal plasma PNP activity was found to be 3.2+/
Russell P. Newton, Elton L.L. Roberts, Alan T. Axford   +2 more
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Functional analysis of purine nucleoside phosphorylase as a key enzyme in ribavirin metabolism.

Drug Metabolism and Pharmacokinetics, 2014
Ribavirin is a purine nucleoside analogue that possesses potent anti-hepatitis C virus activity, and it has long been considered likely that ribavirin undergoes a first-pass metabolism at the small intestine. Although purine nucleoside phosphorylase (PNP)
Tomomi Furihata, S. Kishida, Hanae Sugiura, Atsuko Kamiichi, Minami Iikura, K. Chiba   +5 more
semanticscholar   +1 more source

FISH-MUSCLE PURINE AND PYRIMIDINE NUCLEOSIDE PHOSPHORYLASES

Canadian Journal of Biochemistry, 1967
Three purine nucleoside phosphorylase preparations (isoenzymes) were obtained by ammonium sulfate fractionation and DEAE-cellulose chromatography of aqueous extracts of lingcod muscle. Dialysis, adsorption on alumina Cγ, and elution with 0.4 M phosphate buffer yielded further purification.
Joan E. Roy, H. L. A. Tarr
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[73] Chinese hamster purine nucleoside phosphorylase

1978
Publisher Summary This chapter describes the purification procedure of nucleoside phosphorylase enzyme from Chinese hamster V79 tissue culture cells. Purine nucleoside phosphorylase (purine nucleoside: orthophosphate ribosyltransferase) in eukaryotes catalyzes the reversible conversion among the purine bases, hypoxanthine and guanine, and their ...
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Inhibition of human purine nucleoside phosphorylase by acyclic nucleosides and nucleotides

Biochemical Pharmacology, 1987
In an effort to develop more potent inhibitors of human purine nucleoside phosphorylase (PNP) as immunosuppressive and cancer chemotherapeutic agents, the affinity of the erythrocytic enzyme for 30 acyclic nucleosides, nucleotides and related compounds was determined.
Robert E. Parks, Karkas Jd, Li Sy, Johanna D. Stoeckler, Tolman Rl, Stein Jm, Chen A, Ashton Wt, Malcolm MacCoss   +8 more
openaire   +3 more sources