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Volume 28 (2003)
- Issue 6 Pages 248-
- Issue 5 Pages 206-
- Issue 4 Pages 162-
- Issue 3 Pages 102-
- Issue 2 Pages 46-
- Issue 1 Pages 2-
Volume 28, Issue 3
Displaying 1-8 of 8 articles from this issue
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Molecular Mechanism of the Microdomain (Raft) Formation in the Cell MembranesHideo Akutsu2003 Volume 28 Issue 3 Pages 102-110
Published: May 01, 2003
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSThe intermolecular interactions and microscopic miscibility in the lipid bilayers of single component and binary mixtures were investigated using solid-state NMR. The glycerol backbones of phosphatidylethanolamine (PE), phosphatidylcholine (PC), cardiolipin (CL) and phosphtidylglycerol (PG) were specifically dueterated. The results of 2H-NMR and 31P-NMR analyses have shown that PE is completely miscible with CL and PG, while PC is not. The latter was suggested to form microdomains in the lipid bilayer. This was explained by the ability of hydrogen-bond-network formation of their polar head groups. The microdomain formation also regulates the interaction between lipid bilayers and c-type cytochromes. The biological significances of this nature of phospholipids are discussed.View full abstractDownload PDF (939K) -
An NMR Application to Drug Delivery StudyEmiko Okamura2003 Volume 28 Issue 3 Pages 111-120
Published: May 01, 2003
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSDrug delivery (DD) from water to biomembranes is crucial as a primary step of the bioactivity. The application of highly developed 1H and natural-abundance 13C NMR method to both sides of drugs and membranes is expected to make a significant contribution to advances in the DD study. Taking advantage of the site-selective, noninvasive NMR, we have unambiguously specified the bilayer interface and interior as DD sites on the atomic level. The method can be applied to a variety of drugs including anesthetics, endocrine disruptors, bioactive peptides, and proteins. Dynamic properties of drugs, peptides, and lipid components in membranes have also been monitored by using high power pulsed-field-gradient NMR without labeled nuclei.View full abstractDownload PDF (1706K) -
Shin-ichi Kugimiya2003 Volume 28 Issue 3 Pages 121-127
Published: May 01, 2003
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSFormations of monolayer or bilayer membranes by an amphiphilic functional molecule as a single component are discussed. From mid-90s, functional molecules such as polypeptides, resorcinarenes, cyclodextrins, porphyrins, and block copolymers having amphiphilic groups were studied in order to construct monolayer or bilayer membranes. Polyethylene glycol (PEG) attached hydrophobic rods reduce the interaction between the rods and assist in aggregation in high ordered and stable structure on the air-water interface above specific surface pressure. Vesicle made of bisimidazolylporphyrin having two carboalkoxyphenyl-substitutents may stabilize by hydrogen bond networks by imidazolyl substituents and π-π interactions of porphyrins assembled in the central belt part of the membrane.View full abstractDownload PDF (1050K) -
Kaoru Tsujii2003 Volume 28 Issue 3 Pages 128-134
Published: May 01, 2003
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSPolymer hydrogels that contain a periodic structure of bilayer membranes have been synthesized and characterized as a novel hybrid material. The hybrid gels show some unique properties which cannot be obtained from the individual polymer gels and the bilayer membranes. Iridescent color resulting from the Bragg diffraction of visible light by the periodic structure of bilayer membranes can be changed by controlling the swelling degree of the gel. Introduction of bilayer membranes strongly affects the volume phase transition behavior of the gel. By polymerizing a gel while shear flow is imposed upon the solution to be geled, anisotropic gel has been synthesized. The hybrid gels show more than seven times larger elastic modulus, and can be extended more than three times before fracture than the simple polymer gel. An anisotropic gel shows anisotropic swelling and mechanical properties.View full abstractDownload PDF (1062K) -
Satoshi Kasaoka, Kazuo Maruyama2003 Volume 28 Issue 3 Pages 135-144
Published: May 01, 2003
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSNewly developed liposomes, containing amphipathic polyethylene glycol (PEG) derivatives, are not readily taken up by the macrophages in the RES and hence stay in the circulation for a relatively long period of time. PEG is useful because of its ease of preparation, relatively low cost, controllability of molecular weight and linkability to lipids or protein including the antibody by a variety of methods. The presence of PEG reduces binding of serum protein, i.e. opsonins marking the liposome for clearance by MPS. PEG-liposome can take advantage of the EPR effect (enhanced permeability and retention effect) for efficient targeting binding in the tumor.
The blood clearance of immunoliposomes must be minimized in comparison with rate of extravasation in the tumor. As described above, PEG-liposomes offer the development of immunoliposomes with both long survival times in circulation and target recognition being retained in vivo. For the active targeting following the passive targeting to the solid tumor tissue, Fab' fragment of 21B2 antibody which is anti-human CEA or transferrin (TF) was conjugated to prepared the pendant type immunoliposome (Fab'-PEG-LP or TF-PEG-ILP). TF-PEG-LP could internalized into tumor cells with receptor mediated endocytosis following extravasation into tumor tissue. Such liposomal formulations should be useful for endocytotic internalization of plasmid DNA and other bioactive materials.View full abstractDownload PDF (1400K) -
Yasuyuki Asai2003 Volume 28 Issue 3 Pages 145-150
Published: May 01, 2003
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSE5880, a novel platelet activating factor receptor antagonist, was dispersed in water for use in injectable formulation and the physicochemical properties of the preparation were characterized. The critical concentration for formation of micelles was 0.12 mM. Using area per molecule data, the critical packing parameter was calculated, indicating that the structure of the micelles was spherical and that each micelle containing 49 molecules. The diameter of the micelle was 8.1 nm. The micropolarity in the vicinity of the hydrocarbon region of the micelles was evaluated and compared with other surfactants, including stearyltrimethylammonium chloride and certyltrimethylammonium chroride.View full abstractDownload PDF (635K) -
Nobuaki Mutoh, Hiroshi Fukuda, Toyoko Imae, Ayako Goto2003 Volume 28 Issue 3 Pages 151-154
Published: May 01, 2003
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSThe surface pressure-area (II-A) isotherm curves of pure and mixed monolayers which have been reported by Mori and Imae [Langmuir 11, 4799 (1955)] were analyzed to get the molecular insight into mixed monolayers. The II-A isotherm curves of the pure octadecyldimethylamine oxide {CH3 (CH2) 17NO (CH3) 2, C18DAO}, the pure arachidic acid {CH3 (CH2) 18COOH, AA} monolayers and the mixed monolayers were analyzed to assume the mixed situation between C18DAO and AA at the air-water interface. As a result, it was assumed that part of C18DAO molecules forms mixed clusters with AA molecules and the residual C18DAO molecules exit individually without any formation of mixed clusters with AA in the mixed monolayer. Not only the ratio of the clustered C18DAO molecules to the total C18DAO molecules was estimated, but also the mixed cluster's composition in the mixed monolayers was deduced to be 2 : 1 for AA and C18DAO. The resultant H-A curves well fitted with the observation.
It is concluded that the microphase separation occurs with the mixed clusters as well as free C18DAO molecules in the mixed monolayer.View full abstractDownload PDF (400K) -
Daisuke Tanooka2003 Volume 28 Issue 3 Pages 155-158
Published: May 01, 2003
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSWe have developed Color-Imaging Elliposmeter for measuring in-plane distribution of thin film. Unlike the conventional ellipsometer, this apparatus can measure large area of thin film at high speed. The features of this apparatus are using the incident light with the large diameter for measuring wide area, a 2-dimensional CCD camera, and three wavelengths simultaneously. As an example, we introduce the example of measurement of thickness distribution of SiO2 film on Si substrate and the optical anisotropy of polyimide film with molecular orientation.View full abstractDownload PDF (876K)
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