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K Miyano

Publications and source records attributed to K Miyano.

At least 37 records · Page 2Linked to original sources
PubMed1997

Polysaccharide of Astragali radix enhances IgM antibody production in aged mice.

The effect of Astragali Radix (AR) on IgM antibody production in mice of various ages (10 weeks, 36 weeks and 60 weeks) was examined. The antibody production levels in the 36- and 60-week-old mice were significantly decreased to about 70 and 60% of that in the 10-week-old mice. The enhancement effect of a crude polysaccharide AR fraction on the antibody production was nil in the 10-week-old mice, but significant enhancement effects were observed in the 36- and 60-week-old mice, compared to the age-matched control. Two polysaccharides active in the enhancement of the IgM antibody production in the aged mice were isolated from the high molecular weight fraction of AR by cetavlon precipitation, ion-exchange and gel permeation chromatography. The molecular masses of these polysaccharides were calculated by HPLC in salt solution. Only one major peak was observed for each, and their molecular masses were estimated to be 1.2 x 10(4) and 2.2 x 10(4). The major components of these polysaccharides were neutral carbohydrates (89.3 and 95.5%), followed by uronic acid and protein; glucose was the predominant sugar component.

Aging↗
PubMed1994

[Differential reactivities of three kinds of carbon dioxide absorbents with high concentration of sevoflurane].

The differential reactivities of three kinds of carbon dioxide absorbents, sodalime, Sodalime A and Baralyme with 5% sevoflurane were investigated in a closed system under administration of 5% carbon dioxide. The degradation products in the closed system were determined by gas chromatography and the temperature of the glass container which was filled with each carbon dioxide absorbent was monitored. The degradation products, P1, P3 and P5 were produced by every carbon dioxide absorbents even after one-hour circulation. Especially P3 and P5 were produced by Baralyme more than the others after two or four-hour circulation. The significant differences of the temperature among glass containers were not recognized. Previously we found that the reactivity of Sodalime A is the highest among the three kinds of carbon dioxide absorbents when low concentration of sevoflurane (2 or 3%) is used. Possible explanation for this result is that the increasing temperature of glass container filled with each carbon dioxide absorbent is different from each other, and Sodalime A is the highest. The reactivity was thought to depend on the temperature of glass container. However, with this high concentration of sevoflurane (5%), Baralyme has the highest reactivity. Baralyme contains higher proportion of KOH which has the highest reactivity with sevoflurane than the other constituents of carbon dioxide absorbents. The reactivity of sodalime, Sodalime A and Baralyme with 5% sevoflurane was thought to depend not on their temperature but on their chemical constitutions. These results suggested that the using high concentration sevoflurane with Baralyme should be reconsidered.

Absorption↗
PubMed1994

[Differential reactivities of three kinds of carbon dioxide absorbents with sevoflurane].

The differential reactivities of three kinds of carbon dioxide absorbents, Soda lime, Soda lime A, and Baralyme with sevoflurane were investigated. Sevoflurane was made to react with each carbon dioxide absorbents in a glass vial or in a closed system under administration of carbon dioxide. Glass vials were kept at 55 degrees C and 70 degrees C, and three kinds of carbon dioxide absorbents were compared regarding their reactivity under each temperature. In a closed system, we also monitored the temperature of glass container which was filled with each carbon dioxide absorbent. In a glass vial, the highest reactivity of sevoflurane was found with Baralyme. Although Soda lime A decomposed sevoflurane less than Baralyme or Soda lime in glass vial, the highest reactivity of sevoflurane in a closed system was found with Soda lime A. On the other hand, Soda lime A increased the temperature of glass container most. As increasing temperature tends to promote reaction, the possibility that the high temperature of the glass container contributes to the reactivity of sevoflurane with carbon dioxide absorbents exists. These results suggest that the highest reactivity of Soda lime A with sevoflurane was caused by the highest temperature of glass container although its chemical composition makes it most reactive with sevoflurane than the others.

Calcium Compounds↗
PubMed1993

The effect of halothane dose on striatal dopamine: an in vivo microdialysis study.

The relationship between a level of an anesthesia state and striatal dopamine concentration was investigated. The effect of halothane administration on dopamine level in rat striatal extracellular fluid was determined in tracheotomized rats, using an in vivo brain microdialysis method. The striatal dopamine was increased by halothane doses. The correlation coefficient between halothane and dopamine concentrations was 0.69.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1991

Structural analysis of muscle thin filament.

Thin sheets of Ac-Tm-Tn paracrystals were prepared in the presence of high concentration of Ca2+ ion and three-dimensional image analysis was performed. The optical diffraction pattern of an electron micrograph showed spots up to 1/1.6 nm-1 in the radial direction and up to 1/2.5 nm-1 in the axial direction, the best resolution ever obtained so far. The translationally filtered image showed clear polarity of filament which looked like a "spearhead" per each crossover repeat of actin helix. The three-dimensionally reconstructed model looked very similar to the inner regions (A+B domains) of the Ac-Tm-S1 complex obtained by Toyoshima and Wakabayashi (14, 15) when they were placed so that the "spearhead" pattern of the Tc-Tm-Tn complex and the "arrowhead" pattern of the Ac-Tm-S1 complex pointed in the same direction. The myosin-binding site of actin was identified by comparison of the two structures. The model of actin molecule cut out from the thin filament model had a low density region within itself, which was located about 2.5 nm from the helix axis. That low density region divided actin molecule into two domains, a large and a small domain. A dense "pillar" was detected which connected two neighboring actin molecules along a left-handed generic helix 1 nm from the helix axis. Two actin-actin binding sites which were responsible for the connection through the "pillar" were located on the inner surface of actin molecule. To obtain better crystalline arrays of actin, we tried a method utilizing adsorption to lipid. A positively-charged monolayer of lipids was formed on the surface of a small volume of buffer solution which was put in a microwell. Solution of negatively-charged F-actin was then injected into the buffer solution and was allowed to be joined to the lipid monolayer by electrostatic attraction. Fluidity of the lipid monolayer enabled the two-dimensional crystallization of actin. Electron microscopy revealed that larger paracrystalline arrays were formed more rapidly (less than 1 hr) than those formed within solution, which demonstrated the advantage of this adsorption method.

Actins↗