A significant number of chemicals possess a hormone-like action known for many years since Rachel L. Carson published her article “Silent Spring (published in 1962)” nearly four decades ago, however, little is known about their background mechanism of action. A year before last, an article “Our stolen future” and others revisited the issue were translated and published in Japan. Among the endocrine active compounds, bisphenol A, for example, is known to bind to estrogen receptors, but differently from natural ligand. Another chemicals transmitted through Arylhydrocarbon receptor, such as Benz-pyrene, PBB, TCDD, TCDF, are all known not only to bind any hormone receptors, but also to possess anti-estrogenic health effects. Further, most of chemicals known as possible endocrine disrupters indicate or cause neither mutagenicity nor chromosomal aberration, but show a unique low-dose activity of a so called promotion effect in carcinogenicity.
If not all, disruption of the endocrine may have happened because of receptor mediacy, therefore it should be beneficial to analyze the receptor-mediated adverse mechanism in theoretical manner. Potential mechanisms related to such receptor-mediated adverse effects by chemical ligand include the followings : 1. Unknown receptor-mediated signal cross talk including a variety of orphan nuclear receptors, 2. Redundant receptor binding of a variety of natural and chemical ligands, 3. Pleiotropic expression of receptors to induce pleiotropic actions, 4. Unknown detailed background of the fetal window and delayed effect (s), and 5. Receptor-mediated signal cross talk related to synergy/additive and/or partial agonistic actions. Relevant data available at our laboratory and/or reports will be presented.

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In 20 century, science and technology have been developed and people can enjoy convenient and comfortable life. However global environment has been damaged. For global sustainability of 21 century, new technologies should be developed, and also new evaluation rule for the science and technology newly developed will be necessary.
Many types of polymeric membranes have been developed and commercialized in 20 century and in the next century inorganic membranes should be commercialized. Membrane reactor, in which the inorganic membranes have key role, will be very important, because it has high efficiency in reaction and separation.
Multifunction membranes will be also necessary for the global sustainability in 21 century. With the membrane reactors using these membranes, chemical processes will be simplified, and researches on these membranes have been started.

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Drug delivery (DD) from aqueous medium into biomembranes is crucial as a primary step of the bioactivity. The application of the highly developed NMR method to both sides of drugs and membranes is expected to make a significant contribution to advances in the DD study. We have unambiguously specified the bilayer interface and interior as DD sites on the atomic level, taking advantage of the site-selective, noninvasive NMR. The method can be widely applied to a variety of drugs such as anesthetics and endocrine disruptors (EDs).

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All mammalian cells have “glycocalix” on their surface, which comprises glycolipids, glycoproteins, and proteoglycans. Structures of carbohydrate chains in the glycocalix are cell type specific, and are known to change dramatically during the process of cellular activation or differentiation. Thus, these carbohydrates have been regarded to be potential signaling molecules to show what kind of cells are present in the cellular society and which differentiation stages they are. In this context, it has been hypothesized that there must be “glyco-receptors”, which receive the signals and mediate cellular communications. Only a few cases, however, have been identified so far, and a little is known about how they mediate cellular communications. In the present review, we would like to summarize the results of these “glyco-receptor” researches and discuss the future of this research field.

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Influenza A virus consists of three membrane proteins : hemagglutinin (HA) and neuraminidase (NA) as major membrane viral proteins and M2 protein as a minor membrane protein. The HA mediates the receptor binding and membrane fusion and plays an important role during early phase of infection. Cleavability of the HA is a key determinant of pathogenicity of avian influenza virus and highly virulent new subtype virus A/H5N1 with cleavable HA caused human infections in Hong Kong in 1997. The NA contains the receptor destroying activity which mediates the release of virus from the surface of the infected cells and prevents from aggregation of newly released virus particles. M2 protein functions as a proton channel to release the viral genome into the cytoplasm from virus particles after the membrane fusion.

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Hot-seawater desalination process is much attractive as a novel cost-efficiency process to produce potable water. In the hot-seawater desalination process it is required to remove the scale-forming components in seawater before proceeding to the reverse osmosis membrane in order to prevent the scale forming on the membrane which results in deducing flux. In this study, we proposed that the nanofiltration membrane could be applied to the pretreatment process to remove the scale-forming components in hot-seawater desalination process. The rejection of scale-forming components in seawater on different commercial nanofiltration membranes as well as the temperature dependency of flux, rejection and effective charge density of the membrane was investigated. It was found that a certain nanofiltration membrane showed high rejection for sulfated ion while low rejection for calcium ion in the range of the temperature from 30°C to 50°C.An effective charge density of investigated nanofiltration membranes were at almost constant or slightly decreased in the range of 30°C-50°C.Those results mean the possibility of the application of nanofiltration for the scale removal in the hot-seawater desalination process.

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The gastric flippase has been found recently in isolated hog gastric vesicles. We found here that the flippase ATP-dependently translocates endogenous phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine from the outer (cytosolic) to inner (luminal) leaflet of the vesicle membrane bilayer or to the vesicle interior. In the experiments, vesicles were incubated in the presence and absence of ATP, and change in the distribution of endogenous phospholipids between the outer and inner leaflets was determined. Furthermore, the vesicle diameter was measured by a quasi-elastic laser light scattering method. The diameter significantly decreased during the translocation, indicating that the glycerophospholipids are translocated into the vesicle interior. The decrease in the size depended on ATP hydrolysis and was inhibited by flippase inhibitors such as 2-methyl-8- (phenylmethoxy) imidazo- [1, 2-a] pyridine-3-acetonitrile (SCH 28080) and 4, 4'-diisothio- cyanostilbene-2, 2'-disulfonic acid (DIDS). The gastric flippase, which moves into the apical membrane of the parietal cell upon stimulation, may be a candidate that provides the cytoprotective hydrophobic barrier of adsorbed monolayer on the apical membrane covering the Phospholipid bilayer and the luminal surface of transmembrane proteins.

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A unique new method is described showing the use of microfiltration and ultrafiltration membranes in conjunction with gel permeation in 96 well plates. Using this technique it is possible to clean up DNA sequencing reactions to a level of template DNA purity that makes high DNA loading onto capillary electrophoresis (CE) sequencers possible. Loadings as high as 10, 000 ng allow sequencing on CE to be equal in performance to gel slab electrophoresis. This technique replaces alcohol precipitation for sequencing reaction cleanup with an easily automated process taking 1/6 the time.

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