Glycoproteins urine

Thornley C, Dawnay A, Cattell WR. Fluman Tamm-Florsfall glycoprotein urine and plasma levels in normal subjects and patients with renal disease determined by a fully validated radioimmunoassay. Clin Sd 1985 68 529-535. 

EoUowing po administration moricizine is completely absorbed from the GI tract. The dmg undergoes considerable first-pass hepatic metabolism so that only 30—40% of the dose is bioavailable. Moricizine is extensively (95%) bound to plasma protein, mainly albumin and a -acid glycoprotein. The time to peak plasma concentrations is 0.42—3.90 h. Therapeutic concentrations are 0.06—3.00 ]l/niL. Using radiolabeled moricizine, more than 30 metabolites have been noted but only 12 have been identified. Eight appear in urine. The sulfoxide metabolite is equipotent to the parent compound as an antiarrhythmic. Elimination half-life is 2—6 h for the unchanged dmg and known metabolites, and 84 h for total radioactivity of the labeled dmg (1,2). 

LC-MS with on-line SPE using a RAM pre-column with an internal ODS phase was described by van der Hoeven et al. (95) for the analysis of cortisol and prednisolone in plasma, and arachidonic acid in urine. The samples were injected directly and the only off-line pretreatment required was centrifugation. By using the on-line SPE-LC-MS system, cortisol and related compounds could be totally recovered and quantified in 100 p.1 plasma within 5 min with a typical detection of 2 ng/ml (Figure 11.6(b)). The RAM-type of sorbents, in which the outer surface of the particles is covered with aj-acid glycoprotein, also appear to be useful for direct SPE of... 

Measurement of absorption can be complicated by efflux mechanisms. It is clear that many compounds are actively transported back into the GIT, into the bile or into the urine by efflux proteins. In the case of those in the GIT these may have an impact on the apparent absorption of a compound. Some understanding of the substrate specificity for one of these proteins, P-glycoprotein, is becoming apparent [8, 9], but currently the understanding is limited. At the moment there are no published reliable methods either in vivo or in vitro for predicting the importance of efflux mechanisms for a particular compound in man [10-12],... 

Zanamivir (2) is a potent competitive inhibitor of viral neuraminidase glycoprotein, which is essential in the infective cycle of both influenza A and B viruses. It inhibits a wide range of influenza A and B types in vitro as well as in vivo. The concentrations of inhibiting in vitro plaque formation of influenza A and B virus by 50% in Madin-Darby canine kidney (MDCK) cells were 0.004-0.014 p.mol/L in laboratory-passaged strains, and 0.002-16 p.mol/L in assays of clinical isolates. Due to its low bioavailability, it is delivered by inhalation via the Diskhaler , 10 mg twice daily, or intranasally 2-4 times daily for 5 days. After an intravenous dose of 1 -16 mg, the median elimination half-life was ti/2 = 7 h, the volume of distribution at steady state was Vdss = 16 L, and 90% of the dose was excreted unchanged in the urine. After intranasal and inhaled (dry powder) administration, maximum serum concentrations occurred within 2h and the terminal phase half-lives were 3.4 and 2.9 h, respectively. The bioavailabilities were 10 and 25%, respectively, and 20% after inhalation of zanamivir (2) by nebulizer. 

Fucose from glycoproteins,86-171-176,286,328-329 glycosaminoglycans,36-284-287.33o.33i urine,118 and a range of molds332-333 and blood-group substances334 has been estimated. 

It is highly bound to plasma protein (90% to 95%). The major binding protein is ttj-acid glycoprotein. Plasma half life is 3 to 6 hrs, and excreted through urine (95%) breast milk 5% in faeces as glucuronide metabolites. 

The Carbohydrate Content of Some Glycopeptides and of the Tamm-Horsfall Glycoprotein Found in Normal Urine... 

Comparison of the optical rotatory dispersion exhibited by O-/3-d-xylopyranosyl-L-serine isolated from glycosaminoglycans with those of the two synthetic anomers revealed that the natural material has the /3-D anomeric configuration.159 Moreover, the O-D-xylosyl-L-serine present in normal urine also has the /3-d configuration, as had earlier been suggested.190 The origin of the urinary compound is unknown, but it may be a catabolite of certain glycoproteins. 

VI (Maroteaux-Lamy syndrome) are very rare, and both are associated with urinary excretion of large amounts of dermatan sulfate, although the diseases differ in their clinical manifestations.389 Other forms of this disease that are, at present, unclassified are known, in which chondroitin 4-sulfate is excreted in excessive amounts in the urine.409,410 It is reasonable to suppose that other glycosidase deficiencies may be found to underlie other genetically acquired diseases that involve glycoproteins. 

Humbel R, Collart M (1975) Oligosaccharides in the urine of patients with glycoprotein storage diseases. I. Rapid detection by thin-layer chromatography. Clin Chim Acta 60 143-145... 

---