A pharmacokinetic comparison of the modified release capsule and a plain tablet formulation of mebeverine

This study was conducted to compare the pharmacokinetic properties of the modified release 200 mg capsule of mebeverine and the plain 135 mg tablet of mebeverine after single and multiple doses in 12 healthy subjects in a randomised, crossover design. Single doses were given on days 1 and 7 and multiple doses (200 mg b.i.d. for the capsule and 135 mg t.i.d. for the tablet) on days 2-6 of the study. The 200 mg modified release capsule of mebeverine has extended release properties, as indicated by a lower Cmax, a later tmax and a longer elimination half-life than the plain tablet, while the bioavailability is optimal. No significant accumulation occurs after multiple doses of either formulation. The twice-daily dosage regimen of the 200 mg modified release capsule is a good alternative to the three times daily dosage regimen of the 135 mg plain tablet, because the reduced daily intake is likely to benefit patient compliance.

The carbohydrate-protein binding region in keratan sulfate from bovine cornea, structure of a major binding region oligosaccharide

Peptido-keratan sulfate from bovine cornea was degraded by a combination of desulfation, hydrazinolysis, nitrous acid deamination and NaB3H4 reduction. The tetrasaccharide fraction obtained by gel filtration was studied by degradation with specific exoglycosidases and methylation analysis. The existence of two different binding region oligosaccharide structures was established: The first structure contains one terminal fucose, two mannosine residues and N-acetylglucosamine at the reducing end. In the second structure one N-acetylglucosamine is bound to the protein backbone and substituted with branched 3,6-di-O-alpha-mannosyl-beta-mannose. Both terminal alpha-mannosine residues bear keratan sulfate chains in the 2-position.

The carbohydrate-protein binding region in keratan sulfate from bovine cornea. I. Isolation and partial characterization

We present a defined chemical method for the isolation of the oligosaccharide linking the protein to the disaccharide units of keratan sulfate from bovine corneas. 1) Hydrazinolysis removes the amino acids from the peptido keratan sulfate, and leads to deacetylation of the glucosamine residues but does not split off the sulfate groups. 2) NaB3H4 reduction selectively labels the reducing terminal glucosamine of the chain by converting it to [3H]glucosaminitol. 3) Nitrous acid deamination splits the glycosidic bonds of glucosamine and converts this sugar into 2,5-anhydromannose but also leads to several derivatives of the free terminal [3H]glucosaminitol. 4) Na12CN treatment stabilizes the reactive 2,5-anhydromannose and the terminal compounds containing aldehyde groups in a cyanhydrin reaction. 5) The oligosaccharide structure between the glucosamine residue at the reducing end and the first glucosamine of the disaccharide chain is not degraded by this procedure and is obtained intact and in labelled form. The data so far obtained on this part of the cornea keratan sulfate show that it is heterogeneous and contains besides the terminal glucosamine, mannose and fucose in a similar ratio as found in undegraded keratan sulfate. The predominant compound probably contains three neutral sugar residues.