HDL is a strong negative risk factor for atherosclerotic disease, and perhaps more potent target to prevent and　cure the disease than LDL in Japan. However, no specific compound to raise HDL is clinically available, so that there　is no firm evidence for the clinical effect of the increase of HDL. As our knowledge of regulation of HDL metabolism　has advanced significantly in the past several years, a great effort is being made to develop such compounds, by　inhibiting catabolic reaction of HDL, and stimulating maturation and biogenesis of HDL.　

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Plasma lipoproteins play important roles for lipid homeostasis. Lipoproteins contain triglycerides and cholesteryl　ester in the core. The lipoprotein surface is formed by phospholipids and cholesterol, and various apolipoproteins　are bound to the surface of lipoprotein particles. Lipid emulsion particles have been used as models for plasma　lipoproteins. The lipid emulsions are prepared by the method using a high pressure emulsifier. Compared with plasma　lipoproteins, it is easy to alter the lipid composition of emulsion particles and apolipoproteins bound to emulsion　surface. Various lipids and proteins affect the lipoprotein metabolism, and are associated with hyperlipidemia and　atherosclerosis. However, the roles of many components of lipoprotein particles are still uncertain. Therefore, lipid　emulsions are useful for examining the mechanism of hyperlipidemia and atherosclerosis.

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A number of studies have appeared recently on the underlying mechanism of liposome-cell interactions under in　vitro conditions, in which isolated cell populations or cell lines were used. However, our knowledge of how liposomes　interact with cells, how liposomal physicochemical properties such as size, charge or fluidity, influence the　interactions and the parameters that influence this in vivo is limited. We will summarize and discuss the relevant　studies on this matter in this review.

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Membrane proteins play crucial roles in the mechanism underlying several aspects of cellular function. Nowadays　there are so many attempts for structural studies of proteins, because we believe that the structures give us a lot of　information to understand the functions and mechanisms. Electron crystallography is a way of the structure analysis　by electron microscopy using two-dimensional crystals of the membrane proteins. It is also quite difficult to make the　two-dimensional crystals, as well as the three-dimensional crystals for X-ray crystallography. The number of the　structures solved by electron crystallography is much less than that solved by X-ray. However, it should be a great　advantage that the electron crystallography can analyze the structure of membrane proteins which exist in the lipid　bilayer as they were in vivo. In this manuscript, we would introduce the methods of two-dimensional crystallization　summarizing only a few successful attempts.

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The diseases caused by the membrane disorder or damages are categorized as the Membrane-related diseases.　Alzheimer’s disease (AD), which is one of the membrane-related diseases, has been considered to be accompanied　by the oxidative damage of the neuronal cell membrane. Amyloid β-peptide (Aβ), which is a pathological key peptide　of AD, interacts with biomembrane and this interaction has been recently paid attention from the viewpoints of　not only conformational abnormality but also the influence to biomembrane. And therefore, the modeling of biomembrane　using liposome has been desired to develop the liposome-based sensor system. In this article, we surveyed the　sensor system using liposome. Firstly, the immobilization techniques for preparation of the immobilized-liposome　sensor are surveyed. Secondary, some kinds of sensor have been introduced: (i) (metal affinity) immobilized-liposome　chromatography, (ii) immobilized-liposome quartz crystal microbalance method, (iii) immobilized-liposome　sensor (Amperometric method), (iv) membrane chip system. These techniques have been developed in a framework　of “Membrane Stress Biotechnology”. The above methodologies could provide us the quantitative properties of　stress responsive function of both the protein and the membrane.

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Cell membrane proteins from Geobacillus thermodenitrificans DSM465 were converted into the adenosine (As)　recognition materials by adopting 9-ethyladenine (9-EA) as a print molecule. The converted molecular recognition　sites gave the affinity constant of 4.62 × 104 mol–1 dm3 toward As, which was determined by SPR spectroscopy. It　was demonstrated that cell membrane proteins from G. thermodenitrificans DSM465 would be one of candidate materials　to be converted into molecular recognition materials via an alternative molecular imprinting.

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Gas permeation properties through silica based metal-doped microporous membranes prepared by the sol-gel　method were investigated. In order to control pore size and affinity with permeating gas molecules, especially with　CO2 for CO2/N2 gas separation membranes, nitrates of Ni, Al, Mg metals, and ammonium salt of vanadium were　added to silica colloidal solutions. The molar ratio of additives, Si/M was 9/1. CO2 and N2 adsorption measurements　on pure silica and metal-doped silica powder samples were conducted to estimate the affinity of the membrane materials　with those gases. Pure silica and Ni-doped silica showed the largest amount of adsorbed CO2. Ni-doped silica　membranes showed no attract difference from a typical pure silica membrane for temperature dependencies of gas　permeance, while Mg-doped silica membranes might have relatively smaller effective pores for CO2/N2 separation　and the value of permeance ratio of 57 could be obtained at 50 ℃. On the other hand, V-doped silica membranes had　larger pores and N2 gas permeance increased with decreasing temperature, which would result in lower performance　of CO2 separation. Concerning the Al-doped silica membranes, the affinity with CO2 decreased by addition of Al. In　addition, activation energy of He and H2 for permeation on Al-doped membranes became greater, which suggested　densification of silica network because of Al dispersion in the dense phase.

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NOF COR　ORATION develo　ed ‘EXTRASOME® Q10’, li　osomes containing co-enzyme Q10, for the cosmetic　a　　lication. EXTRASOME® Q10, consisting of hydrogenated soybean lecithin, cholesterol and 0.1% co-enzyme Q10,　is stable for 6 months at 40 ℃. EXTRASOME® Q10 was a　　lied to NB1RGB cells irradiated with UVA of 23 J/cm2,　and the amount of MM　1 at the medium was determined by the ELISA. The results show that EXTRASOME® Q10 of　0.25 μg/ml inhibited the 　roduction of MM　1 at the medium, and returned to the normal condition before the UVA　irradiation.

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