Online ISSN : 1884-6440
Print ISSN : 0385-1036
ISSN-L : 0385-1036
12 巻, 5 号
選択された号の論文の8件中1~8を表示しています
  • 岡田 泰伸
    1987 年 12 巻 5 号 p. 242-249
    発行日: 1987/09/01
    公開日: 2011/03/04
    ジャーナル フリー
    A variety of nammalian cells exhibit membrane potential oscillations composed of repeated hyperpolarizations. Such hyperpolarizing oscillations are usually caused by cyclic increases in the cytosolic Ca2+ ions, which in turn, periodically stimulate Ca2+-activated K+ channels. Intracellular Ca2+ oscillations could be brought about by a feedback relationship between an autocatalytic Ca2+ input and a delayed Ca2+ output. In mouse fibroblastic L cells, the operation of Ca2+ channels and that of Ca2+ pump are involved in the oscillations. The Ca2+ channels are activated by stimulation of membrane receptors to complement components (such as Clq) and nucleotides (such as ATP), which are chemotactic factors for the firboblasts. In human epithelial Intestine 407 cells, stimulation of receptors to intestinal secretagogues (such as acetylcholine, histamine, serotonin and VlP) gives rise to Ca2+ release from some intracellular calcium stores. Under appropriate conditions, receptor stimulation by agonists was found to lead to generation of the oscillations in both cell species. Thus, it is strongly suggested that oscillations of membrane potential and cytosolic Ca2+ occur in the recepor-activated fibroblasts and enterocytes in vivo, and that the oscillations play an important role in Ca2+-mediated cell activities such as fibroblast chemotaxis and intestinal secretion.
  • 宮嶋 孝一郎
    1987 年 12 巻 5 号 p. 250-260
    発行日: 1987/09/01
    公開日: 2011/03/04
    ジャーナル フリー
    Saccharides have been regarded as the strong hydrophilic solutes by virtue of their hydrogen bonding with water molecules. The oxygen positions of equatorial OH groups almost fit the oxygen positions of tridymite structure of water. Therefore, the degree of hydrophilicity is different from each saccharide, because of the different orientation of OH groups. On the contrary, the hydrophobic plane formed by the CH- and CH2-groups is also different from each saccharide molecule and different hydrophobicities are observed for various monosaccharides, though they are considerably weak. The amphipathic character of saccharide molecule, that is, strong hydrophilicity and weak hydrophobicity, has been demonstrated by the studies of the interaction of lipid membranes with monosaccharides and cyclodextrins. The most hydrophilic monosaccharides stabilize the liposome membrane in frozen state, while the most hydrophobic cyclodextrins destruct the liposome membrane at room temperature by recognizing the lipid molecule and forming the inclusion complexes. Bile salts are also included in the cavity of, β-cyclodextrin and liberate the guest molecule by the exchange reaction.
  • 辻 明彦
    1987 年 12 巻 5 号 p. 261-271
    発行日: 1987/09/01
    公開日: 2011/03/04
    ジャーナル フリー
    Proteins are capable of lateral and rotational motion in lipid bilayer membranes. Lateral diffusion of membrane proteins has been studied mainly by the fluorescence photobleaching recovery (FPR) technique, and rotational diffusion by the technique of anisotropy decay of “triplet probes” bound to proteins or by the technique of saturation transfer electron spin resonance (ST-ESR). From these results, it has become clear that motion of proteins in lipid bilayer membranes can be well described as that of a cylindrical particle in a two-dimensional matrix with a viscosity of a few poise.
    However, the protein mobility in cell plasma membranes is, in many cases, largely restricted. This restriction would be due to the interaction of the integral protein with the cytoskeletal proteins. As an example, lateral and rotational motion of an anion channel protein band 3, in human erythrocyte membrane is described. In this case, it is suggested that there are two kinds of restriction/regulation mechanisms. One is the anchoring of band 3 to the cytoskeletal protein network, the other is the trapping in a compartment formed with the cytoskeletal proteins. Based on these studies, the character of lateral dynamics of proteins in biomembranes is disucussed.
  • 木曽 祥秋, 北尾 高嶺
    1987 年 12 巻 5 号 p. 272-280
    発行日: 1987/09/01
    公開日: 2011/03/04
    ジャーナル フリー
    It was possible to measure the interaction between membrane polymer and solutes by liquid chromatography pached with membrane materials. The results obtained from liquid chromatograhy are useful to consider the mechanism of membrane separation and membrane materials. The retention mechanism in liquid chromatography in these systems, however, are not made clear sufficiently.
    In this paper, we described the retention characteristics of inorganic salts and of organic compounds in cellulose acetate-water system, and discussed the retention mechanism and the impacts upon membrane process. Moreover, the other systems of liquid chromatography were also mentioned and the availabillity of liquid chromatography for the study of membrane separation was discussed.
  • 宝谷 紘一
    1987 年 12 巻 5 号 p. 281-288
    発行日: 1987/09/01
    公開日: 2011/03/04
    ジャーナル フリー
    Liposomes undergoing transformation were visualized by real time dark-field microscopy in order to study the role of lipid in morphogenesis of biological vesicular structures. Liposomes were found to transform sequentially in a well-defined manner through one of several transformation pathways. A circular biconcave form was an initial shape in all the pathway and it transformed into a stable thin flexible filament or small spheres via a variety or regularly shaped vesicles which possessed geometrical symmetry. The transformation was reversible up to a certain point in each pathway. Osmotic presure was found to be the driving force for the transformations. Biological membrane vesicles such as trypsinized red cell ghosts also transformed by similar phthways.
  • I蒸気透過法の脱水プロセスへの利用
    中村 明日丸, 牧埜 弘
    1987 年 12 巻 5 号 p. 289-292
    発行日: 1987/09/01
    公開日: 2011/03/04
    ジャーナル フリー
    Possibility of the concentration process of organic aqueous solutions to remove water vapor from vaporized mixtures by permeating it selectively through the aromatic polyimide membranes was studied. Hollow fiber type polyimide membranes show stable performance in most organic vapors at high temperature. For example, they provides as high as 180 of the permeation rates ratio for H2O and C2H5 OH at 120 °C. Therefore, it becomes possible to design the efficient vapor permeation processes operated under higher temperature and pressure.
  • II空気除湿への利用
    中村 明日丸, 牧埜 弘
    1987 年 12 巻 5 号 p. 293-294
    発行日: 1987/09/01
    公開日: 2011/03/04
    ジャーナル フリー
    The applicability of the aromatic polyimide membrane to air-drying system was studied. The premeability of steam is estimated to be 1000 times as large as that of nitrogen based on the experiment with the single hollow fiber. The air with -20°C dew-point can be easily produced by the process using this membrane module having several hundreds hollow fibers. But the obserbed permeability ratio was 300-500.
  • 丹羽 雅裕, 大矢 晴彦, 根岸 洋一, 松本 幹治
    1987 年 12 巻 5 号 p. 295-301
    発行日: 1987/09/01
    公開日: 2011/03/04
    ジャーナル フリー
    Reverse osmotic concentration of aqueous dimethylsulfoxide and aniline solutions was carried out using composite membranes and cellulose acetate asymmetrical membranes. Separation of DMSO and aniline, and flux through the membrane were measured within the following ranges : conc. of DMSO ; 1.5, 3.7, 6.1 wt%, conc. of aniline ;.35, .75, 1.4wt%, operating pressure 4, 5, 6 Mpa.
    PEC-1000 gave the best separation. After RO separation of aqueous aniline solutions, pure water permeation was reduced remarkably with a few exception of the case using ON membrane.
    Membrane constants were calculated by Spiegler-Kedem's transport model. The deviation from their model was corrected by compaction coefficients. Estimated saparations and fluxes were almost the same as experimental value.
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