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T Oe

Publications and source records attributed to T Oe.

At least 37 records · Page 2Linked to original sources
PubMed1989

Immobilized enzyme reactors for detection systems in high-performance liquid chromatography.

The applications of immobilized-enzyme reactors (IMERs) to detection systems in high-performance liquid chromatography (HPLC) have been reviewed. A substrate unresponsive to the detector is enzymatically converted to a highly responsive product. The main analytes detected by this system are various steroids, conjugates of various compounds, acetycholine, choline and amino acids. The repetitive use of a single batch of expensive enzyme has economic advantages. On the other hand, the organic modifier in the mobile phase exerts a considerable influence on the activity and stability of the IMER. Usually the activities of the IMER decrease after two or three months of ordinary use. These problems need to be overcome in the future. HPLC-IMER systems are being used in the field of clinical chemistry, and further applications to other fields are expected to be developed.

Chromatography, High Pressure Liquid↗
PubMed1989

Sensitive ferrocene reagents for derivatization of amines for high-performance liquid chromatography with electrochemical detection.

Six reagents possessing ferrocene as an electrophore were prepared and evaluated for pre-column derivatization of amino compounds for their determination by high-performance liquid chromatography with electrochemical detection. The utility of these reagents was investigated employing phenethylamine as a model compound. Among these six, N-succinimidyl 3-ferrocenylpropionate was the best with respect to reactivity, stability and electrochemical properties. The developed method was applied to the determination of putrescine formed from ornithine by ornithine decarboxylase.

Amines↗
PubMed1989

[An autopsied case of disseminated cryptococcosis with marked lymphadenopathy].

A 75 year old woman who was admitted to Higashisaga National Hospital due to chronic bronchitis showed a high fever (39.2 degrees C) and marked lymphadenopathy of the bilateral inguinal lymph-nodes. Chest X-ray showed diffuse infiltration. Cryptococcus was detected in biopsied lymph-nodes. Although 5-fluorocytosine, miconazole, amphotericin-B were administered for six weeks, she died and an autopsy was performed. Disseminated cryptococcosis was observed in the lung, liver, spleen, kidney, bone marrow, and lymph-nodes of the lung hilum, paratrachea, retroperitoneum, gall bladder and groin. She was a human T cell leukemia type I (HTLV-I) carrier, and this could be related to disseminated cryptococcosis.

Aged↗
PubMed1989

[Synthesis, pharmacological activity and biopharmaceutical characteristics of alpha,2-dimethyl-5H-[1]benzopyrano[2,3-b]pyridine-7-acetates].

The pro-drugs of alpha,2-dimethyl-5H-[1]benzopyrano[2,3-b]pyridine-7-acetic acid(I) with a potent anti-inflammatory activity were synthesized in order to reduce its gastrointestinal side effects. Various esters synthesized were evaluated for their anti-inflammatory activity and ulcerogenicity. Among the compounds maintaining a potent activity of I, N,N-dimethylcarbamoylmethyl alpha,2-dimethyl-5H-[1]benzopyrano[2,3-b]pyridine-7-acetate (II-18) showed excellent biopharmaceutical characteristics. The ulcerogenic effect of II-18 on the rat gastric mucosa was about 3 times less than that of I. It was suggested that II-18 may be an useful biolabile pro-drug for I among the compounds tested.

Animals↗
PubMed1989

[Thromboxane synthetase inhibitors. I. Synthesis of some imidazolylarylmethanols and their inhibitory activity on platelet aggregation].

Several imidazolylpyridinemethanols and imidazolylbenzenemethanols were prepared and evaluated for an inhibitory activity against arachidonic acid-induced platelet aggregation. The result shows that the arylmethanol moiety is essential for the activity and may correspond to the 15-OH group of prostagrandin H2 (PGH2). Among the compounds tested, 4-[alpha-hydroxy-5-(1-imidazolyl)-2-methylbenzyl]-3,5-dimethylbenzoic acid (XV) was found to have a potent inhibitory activity and a long duration of action. Structure-activity relationships are also discussed briefly.

Animals↗
PubMed1989

[Thromboxane synthetase inhibitors. II. Optical resolution of 4-[alpha-hydroxy-5-(1-imidazolyl)-2-methylbenzyl]-3,5-dimethylbenzo ic acid].

The optical resolution of racemic 4-[alpha-hydroxy-5-(1-imidazolyl)-2-methylbenzyl]-3,5-dimethylbenzoic acid (dl-I), a new potent and long lasting thromboxane synthetase inhibitor, was investigated. (S)-3-(3,5-Dinitrobenzoylthio)-2-methylpropionyl group was introduced to alpha-hydroxy moiety of methyl ester of dl-I by three steps of reaction to give the corresponding ester compound (VIa). Then, two diastereomers of VIa, alpha-VIa and beta-VIa, were separated by column chromatography using on silica gel. Alkaline hydrolysis of alpha-VIa and beta-VIa, followed by reactions with sodium ethylate gave optically pure sodium salts of (-)-I and (+)-I, respectively. The separative determination methods for the diastereomers of VIa, and for the enantiomers of the sodium salts of dl-I by high performance liquid chromatography were also established.

Imidazoles↗
PubMed1987

Sensitive ferrocene reagents for derivatization of thiol compounds in high-performance liquid chromatography with dual-electrode coulometric detection.

Three N-substituted maleimides possessing ferrocene as an electrophore were prepared and evaluated for pre-column derivatization of thiol compounds in high-performance liquid chromatography with dual-electrode coulometric detection. The utility of these reagents was investigated by employing N-acetyl-L-cysteine as a model compound. Among the three, N-(ferrocenyl) maleimide was the most favourable reagent with respect to reactivity, stability and electrochemical properties. The dual-electrode coulometric detection of the adduct showed high selectivity and sensitivity with a detection limit of 0.06 pmol. The proposed method is applicable to the determination of glutathione in biological specimens.

Adult↗
PubMed1987

Enhancement of host defence by Y-19995 (2,4'-bis(1-methyl-2-dimethyl-aminoethoxyl)-3-benzoylpyridine dimaleate), a novel synthetic compound. I. Accelerated restoration from the leukocytopenia and augmented protection against microbial infections in immunocompromised mice.

Effects of a novel synthetic compound, Y-19995, on the host defence in immunocompromised mice were investigated in terms of the restoration of leukocytopenia and the protection against several microbial infections. Oral or intravenous administration of Y-19995 into mice after X-irradiation, treatment with cyclophosphamide or mitomycin C prevented the leukocytopenia to some extent and promoted the restoration in cell numbers of both the peripheral blood leukocytes and bone marrow. Intravenous administration of Y-19995 increased significantly the survival rates of X-ray irradiated mice against acute systemic infections with Escherichia coli, Pseudomonas aeruginosa and Candida albicans, and intramuscular infection with Escherichia coli. The clearance of Escherichia coli from the blood of X-ray irradiated mice was also promoted by the treatment with Y-19995. The augmented protection against microbial infections in immunocompromised hosts by Y-19995 may be attributed mainly to the prevention of leukocytopenia or the enhanced restoration from leukocytopenia.

Animals↗
PubMed1978

[Anti-allergic activity of 7-acetyl-5-oxo-5H-[1] benzopyrano (2,3-b] pyridine (Y-9000) (author's transl)].

The IgE mediated reactions such as 48 hr homologous passive cutaneous anaphylaxis (PCA) and active anaphylactic bronchoconstriction in rats were inhibited in a dose dependent manner by treatment with 7-acetyl-5-oxo-5H-[1]benzopyranol[2,3-b] pyridine (Y-9000) and disodium cromoglycate (DSCG) given intraperitoneally. The inhibitory activity of Y-9000 was to the same extent as that seen with DSCG. The IgE mediated reactions were also inhibited by oral treatment with Y-9000 but not with DSCG. In addition, the treatment with Y-9000 resulted in inhibition of IgG mediated reaction such as anaphylactic asthma in the passively sensitized guinea pigs and 4 hr heterologous PCA in rats. However, DSCG failed to prevent these reactions. Y-9000 also inhibited the active systemic anaphylaxis of the mouse and non-immunological reactions in rats such as histamine release after an intraperitoneal injection of dextran, anaphylactoid reaction and paw edema induced by the dextran, egg white or carrageenin. This agent had a stimulating effect on the adrenals, and showed glucocorticoid like activity, but bronchodilator and antagonistic activities on chemical mediators were nil. These results suggest that the anti-allergic activities of Y-9000 are elicited by inhibiting the release of allergic mediators in a manner similar to DSCG, and are partially mediated by stressor activity.

Anaphylaxis↗