HLA-A, B and HLA-DR phenotypes in Mainland Chinese patients with diabetes mellitus

HLA-A, B and DR antigens were studied in Mainland Chinese diabetes mellitus patients and controls (31 Type I DM, 50 Type II DM, 105 controls). HLA-DR3 and HLA-A9 were increased in Type I diabetics only. An increase in HLA-DR4 was noted in Type I diabetics, but the increase was not statistically significant in this small series.

Control of the pilocarpine release rate through hydrogels by plasma treatment

The rate of release of an aqueous solution of pilocarpine hydrochloride sequestered in hydrogel-type materials can be reduced by plasma treatment of the polymer surface. Two plasma techniques were used. The first involves exposure of the hydrogel to the effects of a glow discharge sustained in argon, a process known as CASING. (Crosslinking by Active Species of Inert Gases). The second technique involves the deposition of a thin film by plasma polymerization of organic gases. The gases used in this study were ethane, ethylene and tetrafluoroethylene. Hydrogels were prepared by photopolymerization of 2-hydroxymethyl methacrylate (HEMA), and copolymerization of HEMA with methyl acrylate. The CASING treatment was found to be least effective. The most successful method was the plasma polymerization of tetrafluoroethylene, which yielded an order of magnitude reduction in the flux rate of pilocarpine with a film thickness of 0.25micronm. Polymerization conditions bringing about a crack-resistant film were critical in obtaining the best results.

Reduction of progesterone release rate through silicone membranes by plasma polymerization

An investigation was performed to determine the effectiveness of thin plasma-polymerized films and CASING for controlling the flux of progesterone through poly-(dimethyl siloxane) membranes. It was concluded that up to 40-fold reductions in flux could be achieved with plasma-polymerized films. The principal factors affecting the extent of flux reduction were the nature of the monomer used (ethylene, ethane and tetrafluoroethylene), the film thickness, and the deposition conditions. CASING (Crosslinking by Activated Species of Inert Gases) of the poly-(dimethyl siloxane) membrane surface also proved effective in reducing the flux of progesterone through it.