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Biomedical subjects

H Mukai

Publications and source records attributed to H Mukai.

At least 235 records · Page 13Linked to original sources
PubMed1985

Studies on the absorption of sodium guaiazulene-3-sulfonate. I.

From the view points of safety and efficacy of sodium guaiazulene-3-sulfonate (GAS) after oral cavity administration, the absorption behavior of GAS was investigated in rats and rabbits and following results were obtained. 1) GAS was absorbed not from oral cavity but from nasal cavity in rats and rabbits. 2) The in situ perfusion experiments revealed the existence of dose-dependent specific absorption mechanism in the rat small intestine. 3) GAS was absorbed from neither the rat stomach nor the rectum. These facts reveal that GAS transfers into the systemic circulation only through the small intestine after the clinical application to the oral cavity. And these absorption characteristics of GAS are suited for its direct action on the inflamed oral mucosa. When GAS is administered into the oral cavity, the safety is at least the same as that obtained after oral administration.

Animals↗
PubMed1985

Studies on the absorption of sodium guaiazulene-3-sulfonate. II. Absorption mechanism from nasal and intestinal membrane.

To examine the absorption mechanism of sodium guaiazulene-3-sulfonate (GAS) through the nasal and the intestinal membrane, the apparent absorption rate under the various experimental conditions was measured with the in situ perfusion method in rats, and the apparent partition coefficient of GAS was also determined. The absorption rate of GAS changed biphasically depending on the initial GAS concentration in the perfusate. At the lower concentration range (less than 1 mg/ml), the absorption rate of GAS decreased with the increased in the concentration, and the absorption was inhibited by HgCl2 and ouabain. However, at the higher concentration range (greater than 1 mg/ml), the absorption rate from the nasal mucosa increased markedly with the increase in the concentration, and ouabain had no effect. The apparent partition coefficient of GAS increased with the increase in the concentration of GAS, and GAS was found to be readily transferred to the organic phase by forming ion-pair complexes with the cation such as NH4+ ion. These results suggested that GAS is absorbed through the nasal membrane by at least two kinds of mechanisms: one is a carrier mediated system and the other is a hydrophobic interaction with the nasal mucosa which is increased by forming an ion-pair complex of GAS with cation.

Absorption↗
PubMed1985

Effect of aging on proliferative activity of normal and carcinogen-altered hepatocytes in rat liver after a two-thirds partial hepatectomy.

Proliferative activity of normal and carcinogen-altered hepatocytic populations was investigated in Wistar rats of various ages ranging from 5 to 109 weeks old before and after a two-thirds hepatectomy. gamma-Glutamyltranspeptidase (GGT)-positive hepatocytic foci were induced by administration of a single dose of diethylnitrosamine. The incidence of nuclear labeling with [3H]thymidine was examined using simultaneous GGT histochemistry and radioautography. The [3H]thymidine index of hepatocytes in the GGT-positive foci was not greater than that of normal hepatocytes in both young and old non-hepatectomized rats. GGT-positive hepatocytes responded by proliferating after a two-thirds hepatectomy in all age groups. Although the response of normal hepatocytes to the growth stimulus markedly decreased in old rats, GGT-positive hepatocytic populations retained relatively high responses to the growth stimulus. These observations indicate that in old rats carcinogen-altered hepatocytes have a greater growth advantage than normal hepatocytes to exogenous and endogenous proliferative stimuli.

Aging↗
PubMed1984

Sulfhydryl and disulfide stainings in amyloids of skin-limited and systemic amyloidoses.

Disulfide (S-S) bonds and sulfhydryl (-SH) groups in skin-limited and systemic amyloidoses in frozen and paraffin-embedded sections were examined with a thiol reagent, N-(7-dimethylamino-4-methyl-3-coumarinyl)-maleimide (DACM). In frozen sections, dermal amyloids of skin-limited amyloidoses contained a large number of S-S bonds but no -SH groups [macular amyloidosis (9 cases), lichen amyloidosis (4), and skin tumor-associated (seborrheic keratosis) amyloidosis (1)]. In contrast, amyloids of systemic amyloidoses contained no S-S bonds or -SH groups [primary and myeloma-associated amyloidoses (1 each)]. The identical results were obtained from paraffin-embedded sections in skin-limited amyloidoses [macular (31), biphasic (4), lichenoid (9) and skin tumor-associated Bowen's disease (3), seborrheic keratosis (2), solar keratosis (2), porokeratosis Mibelli (1), and basal cell epithelioma (1) amyloidoses], systemic amyloidoses [primary (3), myeloma-associated (2), and secondary (2) amyloidoses] and tumefactive amyloidoses of the tongue (2). Furthermore, amyloid-like deposits confirmed by various histochemical stainings were found in the epidermis in 27/67 cases of skin-limited amyloidoses in both frozen and paraffin sections. These intraepidermal amyloid-like deposits contained S-S bonds in all cases (27/27) and -SH groups in 10 of 27 cases. In contrast, an intraepidermal amyloid-like deposit was not observed in any systemic amyloidoses (0/9) or tumefactive amyloidoses of the tongue (2). These results showed that skin-limited amyloidoses could be differentiated from systemic amyloidoses by DACM methods (this appears to depend upon the differences of amino acid composition between skin-limited and systemic amyloidoses) and that paraffin-embedded sections were usable for DACM methods. Present study further suggests that amyloids ion skin-limited amyloidoses are, at least in part, derived from epidermal keratinocytes.

Amyloid↗
PubMed1984

Enzyme immunoassay of 11-deoxycortisol.

Enzyme immunoassay of serum 11-deoxycortisol was established by using alkaline phosphatase as a label. The labelled alkaline phosphatase was stable for at least a year. 11-Deoxycortisol in serum was purified by applying to Sephadex LH-20 column prior to present enzyme immunoassay. Separation of bound and free form was carried out by adding anti-rabbit gamma-globulin goat antiserum as a second antibody. The minimal amount of 11-deoxycortisol detected was 40 pg/tube and the measurable range was from 0.04 to 10 micrograms/dl. Intra- and interassay coefficient of variations were 3.8-4.5% and 3.4-5.3%, respectively. 11-Deoxycortisol values determined by the present method correlated well with those determined by radioimmunoassay (r = 0.98, y = 0.93 x + 0.19, n = 28). This enzyme immunoassay satisfied the standard criteria of dilution and accuracy, and is applicable to routine determination of serum 11-deoxycortisol in any clinical laboratory as a non-isotopic immunoassay.

17-Hydroxycorticosteroids↗
PubMed1981

Transformation of bile acids by Clostridium perfringens.

Thirty-five strains of Clostridium perfringens were examined for their ability to transform bile acids, both in growing cultures and by washed whole cells. All of the strains oxidized the 3 alpha-hydroxy group to an oxo group, and all except three converted the same alpha-hydroxy group into a beta-configuration. The oxidative 3 alpha-dehydrogenation was barely detectable under anaerobic cultural conditions but was clearly demonstrated in an aerated system using washed whole cells, with a pH optimum between 7.0 and 9.0. The epimerizing reaction amounting to 10 to 20% conversion was observed in anaerobic cultures and also with resting cells, irrespective of oxygen supply. Both reactions were carried out with seven conventional 3 alpha-hydroxy bile acids, thus producing a series of 3-oxo and 3 beta-hydroxy derivatives that could be examined for gas-liquid chromatographic and mass spectrometric behavior. No evidence for the occurrence of 7 alpha- and 12 alpha-hydroxysteroid dehydrogenase activities among the test strains was found. A highly potent deconjugating hydrolase was elaborated by all of the strains.

Aerobiosis↗