著者
荒磯 恒久
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.19, no.1, pp.3-13, 1994-01-01 (Released:2011-08-16)
参考文献数
26
被引用文献数
1 1

In order to understand the fluid nature of biomembrane, which plays crucially important role in many aspects of life phenomena, the molecular motion of phospholipid and membrane protein is discussed in this review. It is shown that the primary determinant for the fluidity in the lipid bilayer and the rate for diffusive motion of lipid and protein molecules is the width and rate of wobbling motion of phospholipid acyl-chain in the nanosecond time region. For the lateral and rotational diffusion rate of membrane proteins, however, interaction between protein and cytoskeleton is also important as the secondary determinant. The rate of segmental motion of protein is partly governed by the surrounding phospholipid species, suggesting that specific phospholipids support the optimum conditions in protein structure to develop its action.Consequently, the term “membrane fluidity” is complex conception having a hirarchical structure which consists of lipid and protein molecules.
著者
村田 昌之
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.19, no.4, pp.221-230, 1994-07-01 (Released:2011-03-04)
参考文献数
36

Membrane fusion plays a crucial role in intracellular vesicular transport, intercellular fusion and viral infectivity. The fusion reaction has been supposed to underlie the following three steps ; (i) specific docking of two membranes, (ii) perturbation of lipid bilayer at fusion point (s) and formingfusion pore (s), (iii) dilation of fusion pore (s). For the intracellular membrane fusion in membrane trafficking pathways, the recent convergence of genetic and biochemical approaches has led to the identification of a number of proteins that involved in specific docking of two membranes (step (i)). However, the details in step (ii) have not been clarified. In this review, I will focus on putative “fusion peptide” of viral fusogenic proteins as an activator of the step (ii). Through the works on the fusion of liposomes mediated by several synthetic peptides that are derived from the fusion peptide of influenza virus hemagglutinin, we found that the fusion is triggered when the peptides become more hydrophobic under fusion-competent conditions, and also found that the common structural features of the fusogenic peptides is not “amphiphilic helical structure”. The amphiphilic peptides appearto require other factor (s) to cause fusion. I propose that uneven distribution of the side-chain bulkiness of peptide in ordered structure is important factor for fusion active peptide.
著者
内貴 正治
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.5, no.2, pp.70-85, 1980-03-01 (Released:2010-10-21)
参考文献数
162

糖脂質はアシルスフィンゴシンおよびジアシルグリセロールに糖鎖が結合した物質群で動物の細胞膜に局在する. 中性糖脂質は40種以上同定されており, その主な生物活性は細胞の特異抗原性である. 中でも, 血液型抗原活性をもつ糖脂質の研究は盛んでABH抗原, LeaLeb抗原, PIPPk抗原, Ii抗原の化学構造が同定されている。なお諸種の細胞抗原性を荷うと思われる分子量数万の糖脂質の存在も明らかにされ, 膜糖タンパク質との分離および分析手段が要求されている. 酸性糖脂質はシアル酸をもつガングリオシドと硫酸化糖をもつスルポ糖脂質に分類される. 共に酸性基を介してイオンと結合することが重要な機能として考察されている. ガングリオシドの種類は脳で18種以上, その他の臓器も入れれば30種以上同定されている. その主な機能は細菌毒素, ホルモン, 刺激伝達物質に対するレセプター活性である. 最近諸種抗原としての役割も少しずつわかってきた.
著者
大久保 研之
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.25, no.4, pp.177-179, 2000-07-01 (Released:2011-03-04)
参考文献数
5
著者
葛良 忠彦
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.29, no.5, pp.290-294, 2004-09-01 (Released:2011-03-04)
参考文献数
18

Gas-barrier property is a most important factor for food packaging. Now polyvinylidene chloride (PVDC) resins are still in wide use as gas-barrier films. However, PVDC resins as packaging materials have been declining in face of various environmental problems they pose. Under these circumstances, ethylene vinyl alcohol co-polymer (EVOH) films, polyvinyl alcohol (PVA) -coated polypropylene films, MXD6 nylon resins, and silica-or alumina-coated PET films are becoming the mainstream for gas-barrier purposes.Recently, various types of oxygen scavengers have been developed and applied as active packaging materials. PET bottles having oxygen barrier or scavenging properties are now used for plastic beer bottles in Europe and United States. EVOH and MXD6 nylon are used as the oxygen barrier materials. As the oxygen scavenging materials, the blend of MXD6 nylon and cobalt salt are used for PET bottles.In Japan, oxygen scavenging PET bottles are used for plastic tea bottles.
著者
伊藤 新次 吉岡 薫 寺川 美加
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.29, no.1, pp.58-65, 2004-01-01 (Released:2011-03-04)
参考文献数
11

In the ultrafiltration of honey, filtration efficiency can not be expressed by permeate flux because it is necessary to dilute raw honey with water. Instead, rate of recovered sugar (RRS) which considers permeate flux and sugar content, was employed as an indicator of the filtration efficiency in this study.The effect of dilution on filtration efficiency was that RRS increased with a decrease in sugar content at initial stage of filtration. However, at concentration factor (CF) above 1.5, RRS at sugar content of 40% was higher than that at sugar content of 30%. This result was probably caused by changes in characteristics of suspended solids in raw honey due to dilution. In this case, the changes were small when the sugar content was 50%.The effect of operation temperature on filtration efficiency was shown that high RRS was observed at 50°C rather than 20°C and 30°C, however, temperature influenced cake resistance less than sugar content during filtration.The effects of operation pressure and cross-flow velocity on filtration efficiency were that when cross-flow velocity was 1.07-1.6 m/s, RRS increased as pressure increased. Whereas influence of cross-flow velocity on RRS decreased as pressure became decreased.Furthermore, total operation energy was easily calculated using inlet pressure under several filtration conditions to obtain a constant volume of permeate.At constant pressure, the cross-flow velocity was proportional to the energy. At constant cross-flow velocity, there were optimum pressures at each cross-flow velocity for useful filtration.
著者
上山 洋一郎
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.34, no.6, pp.351-354, 2015 (Released:2015-06-14)

Silver ions, while being lethal to single-celled microorganisms, are known to be harmless to human cells. We have adopted highly active fine organic silver grains, developed by combining our long accumulated fine organic synthesis and fine particle technologies, to the filter. Antibodies (also known as immunoglobulin) are used by the immune system to identify and neutralize foreign objects, such as viruses. For the antiviral function, we have applied the specific antibody ‘immunoglobulin yolk (IgY)’ for the filter, and the filter has proved to dramatically reduce the infectivity of type A (H1N1, H3N2) and type B influenza viruses and also of the Avian flu A(H5N1).
著者
吉岡 朋久
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.30, no.1, pp.29-37, 2005 (Released:2015-07-01)
被引用文献数
1 1
著者
水本 隆雄
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.33, no.2, pp.82-84, 2008 (Released:2015-06-17)
参考文献数
4
被引用文献数
7 7

Harnal D is a fast-disintegrating tablet containing fine, modified-release (MR) particles. The dissolution-controlled film on the MR particles consisted of a mixture of water-soluble and -insoluble polymers, with a very smooth particle surface (as determined by SEM observation). During dissolution testing, very fine pores on the surface of the MR particles were formed, and the drug release rate was controlled through these pores. The dissolution-controlled film was usually damaged during the compression process, and thus the dissolution rate increased. However WOWTAB technology, which was applied to Harnal D, can be manufactured at a low compression pressure, thereby avoiding damage to the dissolution-controlled film. In fact, there was no difference in the dissolution rate between the MR particles and tablet.
著者
喜多 英敏
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.33, no.5, pp.247-253, 2008 (Released:2015-06-14)
被引用文献数
1 2

This paperreviews the recent research and development of gas separation membranes. Gas separation propertiesbased on the relationship with the structure–property ofpolymeric materials are summarized and recent advances innew materials attemptingto create a molecular sieving property in order to improve the membrane performance aredescribed.
著者
田中 一宏 酒多 喜久
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.36, no.3, pp.113-121, 2011 (Released:2012-09-14)
参考文献数
48
被引用文献数
2 6

The recent research circumstances of photocatalytic overall splitting of H2O and the membrane separation of H2 and O2 for constructing the hydrogen production system by applying photocatalytic H2O splitting are introduced. Here, the principle of photocatalytic H2O splitting and photocatalysts for the reaction are explained on the historical aspect. Furthermore, the photocatalysts with high photocatalytic ability to the reaction, not only the photocatalysts and photocatalytic systems work under solar irradiation but also those show high efficiency are introduced. Incorporating gas separation membranes into the photocatalytic reactor leads to a safe and energy-efficient hydrogen production process. Since any research of application of gas separation membrane to this purpose has not been found in the literature, our research is introduced. The goal performance that the membrane should achieve to produce safe H2 and O2 streams have been determined by a simple model of a membrane module. Permeability and selectivity of H2 over O2 for silica membranes, carbon membranes, and polyimide membranes have been examined in a temperature range from 35 to 100 °C. Some silica membranes have passed the goal at 100 °C for a wet mixture of H2/O2(2/1).
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.31, no.4, pp.221-223, 2006 (Released:2015-07-01)
被引用文献数
2
著者
大場 哲彦 渡名喜 力 大木 和夫
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.29, no.3, pp.169-179, 2004-05-01 (Released:2011-03-04)
参考文献数
22
被引用文献数
1 1

Laurdan, one of the environment-sensitive fluorescent probes, is useful for monitoring membrane fluidity and is widely used for spectroscopic and imaging applications. In the imaging applications, the generalized polarization parameter (GP), defined by two fluorescent intensities at characteristic wavelengths, is used as a measure of membrane fluidity and polarity. However, time-resolved fluorescent spectra of laurdan revealed that the three excited states concern with the emission spectra. We have measured the steady-state fluorescence spectra and the fluorescence anisotropy of laurdan, prodan and NBD-PE in the DPPC and DLPC bilayers at various temperatures. The spectral dependence on the excitation wavelength is interpreted as the red edge effects that are related to the existence of excited-state distribution of fluorophores on their interaction energy with the environment and the slow dielectric relaxation of this environment. The emission peak of laurdan in the liquid-crystalline phase is independent of the red edge excitation, while prodan and NBD-PE show significant red edge effects. This results strongly suggest that laurdan changes its electronic excited state by the specific interaction with a few water molecules in the bilayers and that in addition the non-specific solvent relaxation causes further spectral shifts in the case of prodan in the bilayers and laurdan in the micella. A new three state model for the absorption and emission of laurdan is proposed. The availability and limitation of the GP method are disscussed.
著者
浅野 真司
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.36, no.6, pp.278-285, 2011 (Released:2012-05-18)
参考文献数
35

Gastric acid secretion in parietal cells is performed by proton pump, H+, K+- ATPase, in combination with several related ion transporters located on the apical and basolateral membranes. In this review I will introduce several recent topics about molecular basis of gastric acid secretion in parietal cells. First, I wish to introduce 3D structures of H+, K+-ATPase resolved recently. The structures demonstrated the interaction between the α- and β- subunits fixes and favors the E2P conformation (the “rachet effect”). The binding site of a K+-competitive inhibitor SCH 28080 on the α- subunit of H+, K+-ATPase was also identified in the 3D structure. Secondly, I wish to introduce ion transporters on the apical membrane necessary for gastric acid secretion. Among others KCNQ1/KCNE2 was identified as a K+ channel involved in K+ recycling and replenishment of K+ in the lumen. Thirdly, I wish to introduce actin-binding proteins, ezrin and Huntingtin interacting protein 1 related (Hip1r), which are necessary for gastric acid secretion. Ezrin is involved in membrane fusion between tubulovesicles and apical membrane whereas Hip1r is involved in endocytosis and regeneration of tubulovesicles from apical membrane. Finally, the roles of parietal cells in differentiation of gastric epithelial cells as well as gastric acid secretion will be introduced.
著者
酒井 清孝
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.37, no.1, pp.2-9, 2012 (Released:2012-09-14)
参考文献数
34

The most commonly used artificial organ is the artificial kidney using dialysis membrane, a machine that performs a treatment known as hemodialysis. This process cleanses the bodies of renal failure patients by dialysis, filtration and adsorption which are simple physicochemical processes. Dialysis membranes account for the largest volume of artificial membranes, far outstripping other fields. Worldwide, the consumption of dialysis membranes has reached some 300 million square meters a year. More than 70% of the dialysis membranes in use are made of polysulfone. This paper describes dialyzers and dialysis membranes so far developed for blood purification.
著者
秋澤 忠男 越川 昭三
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.17, no.1, pp.12-18, 1992-01-01 (Released:2011-03-04)
参考文献数
17
被引用文献数
2 2

Phosphate (P) retention, resulted from renal insufficiency directly or indirectly provides pathogenetic roles to the human body. P related signs and symptoms include osteodystrophy, metastatic calcification, central or peripheral neuropathy, anemia, cardiomyopathy, lipid and carbohydrate mal-metabolisms, immunodysfunctions and so on. From these pathological effects of P, P is regarded as one of the major uremic toxins. In spite of the small molecular weight of P, P always shows lower dialysis efficiency than urea. This result can be partially explained by the interaction between negatively charged P and dialysis membrane. Although computer simulation model represented the increase in dialysis efficiency of P across the positively charged membranes, these membranes have not been clinically available. Dialysis membrane with larger membrane pore size and increased porosity significantly stimulated the P removal, however dialysis efficiency of P remained still lower than urea. From these results, it is strongly expected that membrane technology will succeed in the development of new dialysis membrane with more effective P removal.
著者
福島 義博 熊沢 紀之
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.13, no.2, pp.73-82, 1988-03-01 (Released:2011-03-04)
参考文献数
90

Plasma membrane (Na, K) -ATPase transports 3 Na+ out of and 2 K+ into the cell, and thus the pump is electrogenic. This review describes experiments on topical aspects of the cation movement mechanism of (Na, K) -ATPase, putting emphasis on electrogenic properties, reconstitution, and cation occlusion or deocclusion from the transport enzyme molecule.
著者
青木 隆史
出版者
日本膜学会
雑誌
(ISSN:03851036)
巻号頁・発行日
vol.22, no.3, pp.145-148, 1997-05-01
参考文献数
11

This paper describes that the optically active moieties, ((S) -<I>sec</I>-butylacrylamide (BAAm)), in <I>N</I>-isopropylacrylamide (IPAAm) copolymer chains affected the phase transition behavior and resulted in lower critical solution temperature (LCST) changes responding to foreign tryptophan (Trp). Copolymerization of (S) -<I>sec</I>-BAAm and IPAAm were carried out in DMF at 70&deg;C for 25 h using AIBN. The copolymer was water-soluble and showed the characteristic LCST near 27&deg;C. LCSTs of PIPAAm chains are affected by hydrophobic or hydrophilic nature of comonomers. Since sec-BAAm is insoluble in water, the component exhibited hydrophobic property. Therefore, poly ((S) -<I>sec</I>-BAAm-co-IPAAm) showed lower LCST as compared with that of PIPAAm. The LCSTs of the copolymer in the presence of L-Trp weve higher than those in the absence of the amino acid. It was understood that the optically active moieties in the copolymer stereospecifically interact with L-Trp, relatively enhancing hydrophilic property of the polymer chains. The copolymer increased the LCSTs in response to increasing L-Trp concentration. Hydrogels consisting of these comonomers will exhibit reversible swelling/ deswelling behavior in response to L-amino acids such as L-Trp. The polymers with the optically active moieties demonstrate the chiral discrimination to L-amino acids and are also good candidates to perform chiral separation.