Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The absorption characteristics of ethiofos were studied using the rat in situ intestine circulating perfusion technique. Slow absorption kinetics were observed for ethiofos with varying rates of absorption and metabolism/degradation in situ as a function of buffer and absorption enhancers. In most cases less than 10 per cent of the radiolabeled compound is lost from the circulating perfusate in 90 min. In addition, over the same time period greater than 40 per cent of the intact parent compound was lost by degradation. Much of the difference can be accounted for in the formation of the free thiol metabolite. WR-1065, suggesting ester hydrolysis or metabolic activity. Good stability was observed in all perfusate systems ex vivo indicating that the degradation occurs in situ. The disodium salt of ethylenediaminetetraacetic acid (EDTA) was shown to be an effective absorption enhancer of ethiofos. The enhancement of intestinal absorption by EDTA was dose-dependent resulting in a 20-fold increase in blood levels of ethiofos in the portal blood. Follow-up studies in the rhesus monkey confirm this observation. Salicylate and dimethylsulfoxide (DMSO) also resulted in absorption enhancement although to a lesser degree than that seen after EDTA treatment. Addition of several alkaline phosphatase inhibitors did not significantly improve absorption of ethiofos in the rat small intestine. Proposed mechanism(s) for intestinal absorption and absorption enhancement of ethiofos are discussed.
 ...
PMID:Characterization of ethiofos absorption in the rat small intestine. 165 90

Theophylline was measured with a Kodak Ektachem DTSC using its property of uncompetitive inhibition of alkaline phosphatase. Within- and between-batch reproducibility was satisfactory. Agreement with consensus mean values on quality assessment samples was good as was agreement on patients' samples with a high performance liquid chromatography reference method and an automated fluorescence polarisation immunoassay. At therapeutic theophylline concentrations, no interference was seen with caffeine, theobromine, 1,7-dimethylxanthine, 1,3-dimethyluric acid or 3-propylxanthine. 3-methylxanthine (a theophylline metabolite) gave a positive bias but the concentrations of this metabolite found in serum are such that the clinical significance of this finding is questionable. Salicylate at concentrations which might be found during therapy for paediatric rheumatoid arthritis also gave a positive bias.
 ...
PMID:Theophylline assay on Kodak Ektachem DTSC--performance and interference by structurally-related compounds and salicylate. 276 72