There is increasing evidence that lipid mediators such as arachidonic acid and ceramide are importantly involved in cytokine-induced apoptosis. An L929 subclone, selected for its resistance to TNF cytotoxicity, was inadequate in cPLA₂ activity. The expression of cloned cPLA₂ cDNA in resistant cells caused the sensitivity of cells to increase toward TNF. TNF caused ceramide to accummulate in sensitive but not resistant cells. Ceramide treatment eliminated resistance to TNF and led to cell death in resistant cells. The significance of and possible link between mediators in cytokine-induced apoptosis are thus demonstrated by the present results. The functions of lipid mediators in the cytokine-induced apoptosis are discussed with special attention directed to the interrelationships of these meditors to other mediators reported to date.

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Lysophosphatidylcholine (LPC) that binds to docosahexaenoic acid (DHA) at the sn-2 position (β-DHA-LPC) was prepared by the Lipozyme mediated selective partial hydrolysis of DHA-enriched egg yolk lecithin. The β-DHA-LPC was found to be rapidly incorporated into erythrocyte cells and increase their deformability at 5μM/erythrocyte.

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Silver ion-mediated desulfurization of N-aroyl-S- (disubstituted thiocarbamoyl) -thio-hydroxylamines (1) and disubstituted dithiocarbamic acid phenacyl esters (4) in aqueous solution gives the corresponding their carbamoyl derivatives. On the other hand, the reaction of 4 in acetic acid leads to formation of 2- (N, N-disubstituted amino) -5-phenyl-1, 3-oxathiolium salts in one pot.

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Molecular interactions between liposomes, the surface of which was modified by adding 6mol% of poly (ethylene glycol) -lipid (termed PEG-liposomes), and chondroitin sulfate C (CS) as a water-soluble polymer have been investigated in terms of the particle size, zeta-potential, microviscosity, micropolarity and permeability of PEG-liposomes. The particle size and the absolute value of the zeta-potential of PEG-liposomes were found to increase with increasing concentration of CS added. The permeability of PEG-liposomes was decreased by the addition of CS. These were considered to be caused by the complexation between CS and liposomal PEG-chains and by the further adsorption of CS onto CS-PEG-liposomes. The effect of CS on the microviscosity of PEG-liposomes was dependent on the concentration of CS. The packing state of PEG-liposomal lipid bilayer became most rigid by the addition of ca. 4mg mL^-1 of CS.

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The method for preparing W/O emulsions using liquid crystal formed at Oil/Water interface and the mechanisms of formation were examined in the present study. Water containing N-Lauryl-N, N-dimethyl-Betain (LB) was added to a dispersed phase (Oil phase) containing Oleic Acid (OA) with stirring. Liquid crystals comprised of water, oil and a complex formed by electrostatic bonding between OA in oil and LB in the water was produced at the oil/water interface. Each water droplet was surrounded by a liquid crystal. By this method, concentrated W/O emulsions stable against coalescence and creaming of water droplets with over 90wt.% of the internal phase could be prepared. That the continuous phase became reversed hexagonal liquid crystals with increase in the internal water phase and water droplets were fixed in the reversed hexagonal liquid crystals would be the reasons for this facile preparation.

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Benzene was solubilized in aqueous micellar solutions of a redox-active nonionic surfactant (11-ferrocenylundecyl polyoxyethylene ether : FPEG) and the effect of the redox reactions on the solubilization is studied. The solubilization equilibrium constant (K) of benzene in FPEG micelles, which represents the distribution of solubilizates between micelle and bulk solution, was found to decrease with the oxidation of ferrocenyl moieties of FPEG molecules, but to increase with reduction in ferrocenyl moieties. Active and reversible control of solubilization is thus shown possible through application of the redox reactions of FPEG micellar solution.

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The decoloration of azo dyes such as Orange II and Orange G was examined with horseradish peroxidase (HRP) -H₂O₂ bleaching. The decoloration of Orange II was nearly complete in 2 minutes but with Orange G, decoloration was much slower, due to differences in the decoloration rate between azo dyes can be explained in terms of the chemical structures of the azo dyes. The decoloration of azo dyes increased remarkably in the presence of an activator such as p-iodophenol (p-ID). That of Orange Gin the presence of p-ID was sufficient to inhibit Orange G transfer. Optimal HRP concentration decreased in the presence of p-ID by one tenth compared with HRP-H₂O₂ bleaching alone. The transfer of dissolved Orange II to nylon fabric and decoloration of Orange II-dyed nylon during bleaching were examined by HRP-H₂O₂-p-ID bleaching. Orange II was rapidly destroyed and the transfer of Orange II to nylon fabric ceased as a result. No decoloration of Orange II-dyed nylon occured during bleaching.

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Benz (a) anthracene (BaA), pyrene, benzo (a) pyrene (BaP), and benzo (ghi) perylene in heavy oil that had washed ashore, after leaking from a wrecked Russian oil tanker, the Nakhodka, disappeared by 99%, 92%, 60% and 33%, respectively, through the action of Mycobacterium sp. H2-5 at 30°C over a period of 20 days. This bacterium had been initially isolated as a pyrene-assimilating bacterium in 1994. PAHs in commercial heavy oil (class C) disappeared by 92%, 99%, 60%, and 10%, respectively, by the bacterium under the same conditions. The disappearance of PAHs in the two heavy oil samples by strain H2-5 was essentially to the same extent. The bacterium thus prevented any damage from the drifting of heavy oil.

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Triolein adsorption on attapulgite or sepiolite was measured in triolein hexane solution containing with constant β-carotene content. The adsorption isotherm of triolein could be well expressed by the Langmuir equation. The triolein adsorption coefficient, b obtained from β-carotene-triolein solution was exceeded that from triolein solution. Small amounts of triolein adsorbed on attapulgite or sepiolite are thus shown to be partially or fully covered by adsorbed β-carotene.

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