Alteration of basement membrane component in diabetes mellitus was reviewed. Recently, it has become evident that the basement membrane was composed of type 4 collagen, laminine and glycosaminoglycans. Presence of entactin and type 5 collagen was also claimed. Existence of fibronectin is controversial. Previously, studies on the basement membrane in diabetes were mainly concerned in the collagenous components. However, studies on the components other than collagen will be more important because they bear roles for the morphogenesis, metabolism and functions of basement membrane.
Recently it was demonstrated that the glycosaminoglycans were reduced in diabetic basement membrane. Reduction of negative charge of basement membrane due to the loss of acidic residue of glycosaminoglycans was claimed to be the cause of the loss of charge selectivity observed in diabetic nephropathy. Fibronectin was reported to be increased in the renal glomeruli of the initial stage of diabetic glomerulosclerosis and to be decreased in the advanced nephropathy. Studies on laminin produced by EMS tumor implanted to the diabetic mice revealed no consistent changes. In diabetic glomerulosclerosis, laminin was reported to be decreased. Speculation on the mechanisms of the basement membrane thickening in diabetic microangiopathy was made on the bases of the reported evidences on the alteration of basement membrane components.

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Extremely halophilic bacteria, halobacteria produce purple membrane in the plasma membrane. On absorption of light purple membrane pumps protons from the cell, resulting in the production of proton gradient across the membrane and membrane potential, so purple membrane is one of energy converters of light. The purple membrane contains only one species of protein called bacteriorhodopsin because this protein possesses retinal as the chromohpore like a visual pigment rhodopsin. The bacteriorhodopsin plays a role as a photoelectrogenic tip in the purple membrane.
In this article the structures of purple membrane and bacteriorhodopsin were introduced and the energy conversion mechanism in the bacteriorhodopsin was discussed. Especially researches on bacteriorhodopsin with retinal analogs and by chemical modification were commented.

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Relations between membranes and enzymes are presented from the chemical engineering view point. First, application of membranes to enzyme reactors is given. Recent topics are reviewed. Two topics, i. e. the membrane reactor applying the pressure swing operation and enzyme immobilization by the use of the Coulomb force, are discussed. Second, the use of membranes to separation processes relating with enzymes is presented. Results are shown for membrane separation of enzymes by using electrophoresis and for the continuous isoelectric focusing. Finally, future view on the reactors and separation processes using membranes is discussed.

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A rapid, sensitive and all round stain was developed for visualizing protein in sodium dodecyl sulfate (SDS) -polyacrylamide gel electrophoresis (PAGE). The procedure is simple and economical using no special device, and the stained bands are clear and distinct. This stain detects 1 microgram quantities of protein in band color of several colors at the shrunken gel.

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Three types of reverse osmosis cellulose acetate (CA) membranes were prepared under the shrinking temperatures of 60°C (CA-I), 70°C (CA-II) and 90°C (CA-III) respectively. The rejections of nonionic surfactant Tween-80 were more than 95% in the CA membrane heat-shrunk at 60°C (CA-I) while other solutes showed less than 25% rejections in the same membrane. Also solute rejection increased and flux decreased substantially when Tween-80 was added to the feed solution.

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A composite membrane made from polyethylenimine (PEI) coated on a microporous polysulfone support and crosslinked with m-tolylene-2, 4-diisocyanate (TDI) was used to investigate the reverse osmosis performance of EtOH-H₂O mixture. Applied pressure ranged 20-80 kg/cm². Permeation rate in this range were proportional to operating pressure, being 20-110×10^-5 cc/cm²-sec. With 2% of PEI and 2% of TDI, solute rejection was reached to 64%, which was superior to DDS-HR-98 membrane but lower than PEC-membrane (Toray Industries, Inc.), while permeation rate of water was 60×10-5 cc/cm2-sec which was superior to that of PEC membrane.
Some parameters relating to the reverse osmosis performance, A, σ, α, β and D_EM/Kσ were determined experimentally for PSET membrane with a view to assist the design of reverse osmosis system of aqueous ethanol solution.

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