PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “URATE OXIDASE”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 469 records · Page 26Linked to original sources
PubMed1979

Immobilized enzymes in continuous-flow analysis.

Glucose oxidase, uricase, and urease were immobilized on the interior surface of activated polyamide tubing. The shelf-life of such enzyme bearing tubes was at least six months. The tubes were used for continuous-flow analysis of glucose, uric acid, and urea with conventional systems and with hybrid micro-scale systems in which modules of different manufacture were combined. The length of enzyme-bearing tube required for each system was ascertained empirically. Each tube could be used for several thousand assays, but glucose oxidase-bearing tubes were more stable than urease- or uricase-bearing tubes. Results for patients' samples correlated well with results obtained by accepted methods.

Autoanalysis↗
PubMed1975

Copper ion binding and enzyme inhibitory properties of the antithyroid drug methimazole.

The antithyroid drug, methimazole (1-methyl-2-thiolimidazole), is a powerful chelator of cupric ion. This is reflected in its ability to selectively inhibit certain copper oxidases. Uricase, ascorbic oxidase and monoamine oxidase are not affected. Ceruloplasmin oxidase is slightly inhibited and tyrosinase is markedly inhibited by methimazole.

Ascorbate Oxidase↗
PubMed1996

Pharmacodynamics of oxypurinol after administration of allopurinol to healthy subjects.

1. Eight healthy subjects received 50, 100, 300, 600 and 900 mg allopurinol daily for 1 week each, in random order with 1 week separating each treatment period. The pre-dose plasma concentration of oxypurinol, the extent of inhibition of xanthine oxidase, plasma urate concentration and urine urate excretion rate were assessed on the last 2 days of each treatment week. 2. The ratio of 1-methyluric acid (1MU) over 1-methylxanthine (1MX) in the urine, following a dose of 50 mg 1MX infused intravenously over 20 min, was used to measure the inhibition of xanthine oxidase. 3. The steady-state plasma concentration of oxypurinol increased linearly with increasing dose of allopurinol between 50 mg to 600 mg day-1, with a weak indication of saturation at the higher 900 mg day-1 dose rate. 4. The relationships between plasma oxypurinol concentration and xanthine oxidase inhibition (1MU/1MX ratio), plasma urate concentration and urine urate excretion rate were fitted to an inhibition sigmoid Emax model and the C50 values for oxypurinol were 26.38 +/- 4.87, (mean +/- s.d.) 36.58 +/- 8.36 and 24.61 +/- 9.08 microM, respectively. 5. 1MU/1MX ratio appeared to be a reliable index of xanthine oxidase activity in vivo as the C50 for oxypurinol observed for 1MU/1MX ratio, plasma urate concentration and urine urate excretion rate were similar. 6. The concentration of oxypurinol required for inhibition of xanthine oxidase, as indicated by C50, was lower than those often observed in clinical practice.

Adult↗
PubMed1978

Determination of uric acid on continuous-flow (AutoAnalyzer II and SMA) systems with a uricase/phenol/4-aminophenazone color test.

This report describes a new specific colorimetric procedure for uric acid assay with AutoAnalyzer II and SMA (Technicon) systems, made specific by the application of uricase. Hydrogen preroxide, formed in this reaction, effects the oxidative coupling of 4-aminophenazone and 2,4-dichlorophenol under the catalytic influence of peroxidase. The red dye formed is measured at 505 or 520 nm. A sample blank measurement is not necessary, and the reagents show very good stability. The test shows linearity up to 714 mumol of uric acid per liter. Results of thie method correlate very well with those by the uricase-ultraviolet and uricase--catalase methods. There is no interference by hemoglobin, bilirubin, lipemia, and various drugs, except a minor interference by alpha-methyldopa. Interference from ascorbate is eliminated by ascorbate oxidase. This method can be regarded as a considerably improved routine test for uric acid on continuous-flow systems in clinical laboratories as compared with the commonly used phosphotungstate method.

Aminopyrine↗