The human erythrocyte membrane is best characterized biomembrane in terms of its structure and function on a molecular bases. The membrane glycoproteins can be classified into two groups, which are sialoglycoproteins and polylactosaminylglycoproteins. The former includes glycophorin A, B and C, and the latter includes Band 3, Band 4.5 and glucose transporter. These two classes of glycoproteins differ from each other in carbohydrate structure, in the modes of orientation in lipid bilayer, and in their functions.
The cell surface glycoproteins are significantly changed during the course of erythroid differentiation. The characterization of glycoprotein by cell surface labeling and endo-β-galactosidase treatment revealed the following stage-specific membrane glycoproteins : Gp 80 for the progenitor cells, Gp 95 for proerythroblasts, and Gp 105 for erythroblasts. Considerable evidences suggests that the microenvironment, including cell to cell interactions, play a role in controlling the differentiation of haematopoietic cells. The possibility that of specific surface glycoproteins are involved in cellular recognition is also discussed.

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Microbial cells, tissue cells and organelles have coupled biocatalyst system which catalyze multi-step biochemical reactions. Immobilization studies, including radiation polymerization method, for these biocatalysts were reviewed. Comparative studies of some immobilization methods and of artificial membranes or matrices for immobilization offered some clue to design artificial membrane or matrix for immobilization. For more detailed design, however, studies of following two other types are required. The studies for the variation of state in these biocatalysts corresponding to continuous physical, chemical changes in artificial medbrane or matrix for immobilization. Physical and chemical studies for the difference of state in these biocatalysts between before and after immobilization.

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“Metallo-carriers” mediate membrane transport of amino acid and oligopeptide derivative anions, providing new chemical analogues to biological amino acid transport and prototype for anion-separation membrane. Appropriate choice of metallo-carriers could allow accurate control of transport efficiency and selectivity.
Using transition metal complex carriers, Gly- and Ala-derivatives are much more effectively transported than Phe- and Leu-derivatives via “antiport mechanism”. Their transport properties are significantly determined by the natures of ligand molecule, central metal cation, and antiport anion. Active transport of amino acid derivatives is also achieved by some metallo-carriers.
Macrocyclic crown ether-alkali metal cation complex carriers exhibite marked contrasts to the transition metal complex carriers in the anion transport process. They selectively transport Phe- and Leu-derivatives via “symport mechanism”. As well as crown ether and cryptand compounds, some linear polyethers offer specific transport of amino acid derivatives.
In addition to transportation, such artificial carriers perform other interesting functions : Highly selective hydrolysis of amino acid esters is realized in synthetic carrier-functionalized membrane system. Further extensions may be anticipated in the wider related fields.

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This article deals with the analysis of D-glucose and several drug transport systems using plasma membrane vesicles derived from fibroblasts and renal epithelial cells. Membrane vesicles isolated from non-transformed fibroblasts and from transformed cells displayed carrier-mediated and stereospecific transport of D-glucose, and retained many of the features of the increased glucose transport observed in whole cells in association with viral transformation. The transport systems in brush border and basolateral membranes isolated from kidney cortex differ from one another : brush border membranes catalyze secondary active transport of D-glucose by an electrogenic Na⁺ symport mechanism and carrier-mediated transport of amino-β-lactam antibiotics, and basolateral membranes catalyze carrier-mediated transport for p-aminohippurate (organic anion).

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Reverse osmotic concentration of aqueous ε-caprolactam solutions was carried out using composite membrane PEC-1000 supplied from Toray Co. Ltd. Separation of ε-caprolactam and flux through the membrane were measured under the following conditions : concentration of ε-caprolactam, 2.5, 5.0, 10.0 and 14.5wt%, operating pressures, 3.9, 5.5 and 6.9 MPa. Measured separations were always above 99.9%. Mass transfer coefficients on the surface of the cell used were measured using electrochemical method.
An analysis of the data with Spiegler-Kedem's transport model shows that the values of reflection coefficient σ, solute and hydraulic permeabilities ω and L_P were 1.0, 3.86×10^-13 and 5.29×^-8 mol/ (m². Pa.s), respectively.
Energy and membrane area required were calculated to concentrate dilute ε-caprolactam solutions by reverse osmosis. The energy per one kilsgram of the concentrated ε-caprolactam is inversely proportional to the initial concentration ofε-caprolactam and independent on the final concentration, and found 0.0565, 0.079 and 0.113 kWh/kg ε-caprolactam at 5, 7 and 10 MPa respectively to concentrate upto 20wt% from 2.5wt%.The area is inversely proportional to the operating pressures, and found 0.16, 0.10 and 0.06 m²/ (kg ε-caprolactam/day) for 5, 7 and 10 MPa, respectively.

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Separation factors and permeation rates by pervaporation were measured for various organic solvents-water systems using the silicone rubber membrane. It was found that this membrane permeated organic solvents prefferentially compared to water, and this characteristic was different many other memdranes reported so far. This nature is very useful for the separation and the concentration of dilutes organic and permeation rates can be estimated by using permeation rates of pure components, except for the case of swelling. For this latter case the superficial rates was adopted, which can be obtained by the experiment of mixture permeation.

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Goodpasture's syndrome is defined as those with triad of findings : glomerulonephritis, pulmonary hemorrhage and antiglomerular basement membrane (anti-GBM) antibody production.
Characteristic clinical and histopathological features of Goodpasture's syndrome are reviewed and summarized. Recently, analysis of the anti-GBM antibody by chemical or immunohistological technique has shown the heterogeneity of the glomerular basement membrane (GBM) antigenicity, which might be led to the pathophysiological difference between glomerulonephritis with pulmonary hemorrhage in Goodpasture's syndrome and anti-GBM antibody induced glomerulonephritis without alveolar bleeding in rapidly progressive glomerulonephritis.
Etiology and the mechanism in detail of the anti-GBM antibody production are further to be clarified.

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