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S Oida

Publications and source records attributed to S Oida.

At least 73 records · Page 4Linked to original sources
PubMed1990

Chondrocyte-like colony formation of mesenchymal cells by dentin extracts in agarose gel culture.

In this study, the effects of guanidine extracts from demineralized bovine dentin matrix on rat mesenchymal cells were investigated by use of an agarose gel culture. The dentin extracts were divided into water-soluble and -insoluble fractions. Rat mesenchymal cells obtained from the cultivation of skeletal muscle tissue and embedded in agarose gel were treated with these two fractions. After three weeks of cultivation, the treated cells formed colonies that were stained metachromatically with toluidine blue in a dose-dependent manner. The activity necessary to form chondrocyte-like colonies by the water-insoluble fraction was significantly higher than that by the water-soluble fraction. Each chromatographic fraction of the water-insoluble part of dentin extracts on tandem Sephacryl S-200 High-resolution columns was also investigated. Chondrocyte-like colony-forming activity was concentrated in a single fraction. However, the electrophoretic pattern of this fraction revealed that there were still some bands of molecular weight between 18 and 30 kDa. According to the Western blot analysis of this fraction, there was a band corresponding to purified transforming growth factor beta (TGF-beta) under the non-reducing condition. After reduction, this band disappeared and we found a band corresponding to a component of 13 kDa as well as TGF-beta. These findings suggest that TGF-beta is present not only in bone but also in the dentin matrix.

Animals↗
PubMed1990

Synthesis and antifungal activities of some thiolane-triazole derivatives.

As part of our search for active agents against systemic fungal infections, a new series of triazole compounds with a thiolane ring was synthesized. Their antifungal activities were investigated in vitro and in vivo. Some of these thiolanetriazoles showed promising activity, comparable to that of ketoconazole, against a mouse systemic Candida albicans infection, after oral or parenteral dosing.

Animals↗
PubMed1990

Triazole antifungals. II. Synthesis and antifungal activities of 3-acyl-4-methyloxazolidine derivatives.

Triazole compounds with an oxazolidine ring were designed and synthesized as a potential inhibitor of the fungal cytochrome P450 14 alpha-demethylase. In testing for antifungal activity against a mouse systemic Candida albicans infection, (4R,5R)-3-acyl-4-methyloxazolidine derivatives 4 exhibited remarkably high efficacy after oral or parenteral dosing. The potent activity of 4 is hypothesized to be a consequence of a structural similarity between 4 and lanosterol, a target molecule of the cytochrome P450 14 alpha-demethylase. Highly stereoselective synthesis of these oxazolidines is also described.

Animals↗
PubMed1988

Detection of minor immunological differences among human "universal-type" alkaline phosphatases.

Two clones of monoclonal antibodies against swine alkaline phosphatase (ALPase; orthophosphoric monoester phosphohydrolase, alkaline optimum, EC 3.1.3.1), which were useful in distinguishing human kidney and bone ALPases from liver ALPase, were successfully raised in mice. On the other hand, polyclonal antibody cross-reacted not only with human kidney ALPase but also with all other human universal type ALPases. The difference in cross-reactivity of monoclonal and polyclonal antibodies may be caused by the specific antigenicity of human enzymes. The monoclonal antibodies were able to recognize minor heterogeneity that could not be distinguished by their enzymatic properties. The present monoclonal antibody preparations will be utilized for clinical as well as basic investigations to detect minor heterogeneity among universal-type ALPases.

Alkaline Phosphatase↗
PubMed1988

Chondrogenesis and osteogenesis of bone marrow-derived cells by bone-inductive factor.

Rat bone marrow cells were intraperitoneally implanted within a diffusion chamber with a decalcified bone matrix or a 4 M guanidine hydrochloride extracted matrix (G-res) as control. The chamber was harvested after 28 days and soft X-ray photography, histological examination, determination of alkaline phosphatase activity and calcium content were performed. With the decalcified bone matrix, cartilage and bone formation was observed and both alkaline phosphatase activity and calcium content were significantly higher than those in control chambers. Each chromatographic fraction on Sephacryl S-200 of the 4 M guanidine hydrochloride extract (G-ext) from the decalcified bone matrix was reconstituted with G-res and implanted either subcutaneously or intraperitoneally within a diffusion chamber with marrow cells. Intrachamber or subcutaneous cartilage and bone formation was detected by only one chromatographic fraction. When marrow-derived fibroblast-like cells were implanted intraperitoneally within a diffusion chamber with a decalcified bone matrix, cartilage and bone formation was detected, which was not the case with G-res. These results suggest that a certain factor, probably bone morphogenetic protein, which induces ectopic bone formation, allows marrow cells to differentiate into bone and cartilage tissues and there may exist so-called "inducible osteoprogenitor cells" in the marrow-derived fibroblast-like cell preparation.

Animals↗
PubMed1988

Determination of L-6-keto-piperidine-2-carbonyl-L-leucyl-L-proline amide (RGH-2202), a new analog of thyrotropin-releasing hormone, in plasma by radioimmunoassay.

A sensitive and specific radioimmunoassay has been developed for the determination of L-6-keto-piperidine-2-carbonyl-L-leucyl-L-proline amide (RGH-2202), a new analog of thyrotropin-releasing hormone (TRH), in plasma. An antiserum was produced in guinea pigs immunized with RGH-2202 which was conjugated to bovine serum albumin by an N-succinimidyl ester method. Iodine-125 labeled L-6-keto-piperidine-2-carbonyl-L-leucyl-L-prolyltyramine [( 125I]RGH-2202) was used as a tracer. Polyethylene glycol was used to separate bound and free [125I]RGH-2202 in the reaction mixture. The assay of RGH-2202 in plasma was possible over a concentration range from 0.1 to 6.4 ng/ml, using 0.1 ml of plasma without the need for an extraction procedure. The antiserum used for the assay was highly specific for RGH-2202, and did not cross-react with TRH and the hydrolyzed derivatives of RGH-2202 such as L-6-keto-piperidine-2-carbonyl-L-leucyl-L-proline, L-6-keto-piperidine-2-carbonyl-L-leucine and L-leucyl-L-proline amide, which were assumed to be present in plasma as metabolites. The coefficients of variation were 4.6-6.7% for within-assay and 6.0-8.8% for between-assay. Plasma levels of RGH-2202 in rats were determined after an intravenous administration of RGH-2202 at a pharmacologically effective dose (0.625 mg/kg).

Animals↗
PubMed1988

Response of the mouse femoral muscle to an implant of a composite of bone morphogenetic protein and plaster of Paris.

A composite consisting of 1 mg of bone morphogenetic protein (BMP) and 5 mg of plaster of Paris (PLP) was implanted into the mouse femoral muscle. Control PLP without BMP was implanted into the contralateral muscle. The BMP/PLP composite induced cartilage formation within two weeks, trabecular bone within three weeks, and lamellar bone including bone marrow within six weeks. PLP did not disturb BMP-induced bone formation. In addition, the BMP/PLP composite was resorbed early after implantation. These results suggest that PLP composite system is one of the most suitable BMP delivery systems currently available.

Animals↗
PubMed1986

Determination of bovine enamel protein by enzyme-linked immuno-adsorbent assay.

A specific enzyme-linked immuno-adsorbent assay for enamel protein of the developing tooth was devised, using antibody against antigen prepared from immature bovine enamel. Samples containing 5-500 ng of amelogenin protein in 50 microliters gave consistent results. Bovine enamelin cross-reacted with the antibody but was less reactive than amelogenin. Proteins in other tissues or fluids did not react to the antibody.

Amelogenin↗
PubMed1985

Purification and subunit structure of alkaline phosphatase from bovine enamel organ.

A highly-purified alkaline-phosphatase preparation having a specific activity of 703 U/mg protein was obtained from bovine enamel organ by a series of procedures: butanol extraction, isoelectric and acetone precipitation, ion-exchange, concanavalin A affinity and gel-filtration chromatography. The purified enzyme showed the same properties as kidney-type isozyme and contained carbohydrate moieties which react with concanavalin A. Analysis by polyacrylamide gel electrophoresis showed that the purified enzyme split into half the size of the native molecule (160,000 in mol. wt) after being heated in sodium dodecyl sulphate (SDS) solution and the subunit had no catalytic activity. The results indicate that the enzyme is a dimeric glycoprotein comprised of two identical subunits, each having a molecular weight of 80,000.

Alkaline Phosphatase↗
PubMed1984

Purification of swine kidney alkaline phosphatase by immunoaffinity chromatography.

A homogeneous alkaline phosphatase preparation was obtained from swine kidney cortex by a simple purification step of immunoaffinity chromatography. The enzyme was purified 426 times that of the initial acetone powder with a recovery of 69.6% and a specific activity of 1206 units/mg of protein. The sodium dodecyl sulfate-gel electrophoretic pattern showed a single 80,000-Mr protein band as the monomer of the purified enzyme.

Alkaline Phosphatase↗