Showing papers by "Yasuaki Ogawa published in 1999"
TL;DR: The present ELISA is so rapid, sensitive and selective for TAK-778 that it could be conveniently used in a clinical field for the determination of many serum specimens.
Abstract: TAK-778, ((2R, 4S)-(-)-N-[(4-diethoxyphosphorylmethyl)phenyl]-1, 2, 4, 5-tetrahydro-4-methyl-7, 8-methylene-dioxy-5-oxo-3-benzothiepin-2-carboxamide), is a novel osteoblast differentiation-promoting compound, and its sustained-release formulation is expected to be clinically used for the enhancement of fracture healing. To date, TAK-778 levels in serum have been measured using conventional reverse-phase HPLC with inferior sensitivity and time-consuming procedures. We have produced polyclonal antibodies against TAK-778 by using one of its derivatives coupled with a carrier protein, and developed a one-step ELISA for the determination of TAK-778 in serum. The antibodies had minimal cross-reactivities to the biologically inactive metabolites including the oxidized-form (0.36%) and the cleavaged-form (0.00083%). The competitive ELISA was accomplished within three hours with a detection limit of 0.5ng/ml serum, and the coefficients of variations for samples ranging from 1 ng/ml to 80 ng/ml were 1.1-4.4% in an intra-assay and 3.1-9.6% in an inter-assay. The present ELISA is so rapid, sensitive and selective for TAK-778 that it could be conveniently used in a clinical field for the determination of many serum specimens.
7 citations
Patent•
05 May 1999
TL;DR: In this article, a polylactic acid and copolymer of glycolic acid and a hydroxycarboxylic acid was used for a prolonged release drug preparation.
Abstract: 1. A polymer for a prolonged release preparation which comprises (A) a polylactic acid and (B) a copolymer of glycolic acid and a hydroxycarboxylic acid of general formula wherein R stands for an alkyl group having 2 to 8 carbons, and wherein the weight ratio of (A) and (B) is in the range of 10/90 to 90/10. The drug is released at a constant rate from the preparation over the total release period without a large burst at the initial stage. Furthermore, the drug release period of the preparation can be freely controlled by varying the blending ratio of (A) and (B).
4 citations