A method is presented to crystallize polycarbonate of bisphenol A under constant vapor pressure of solvents at near ambient temperatures. Methylene chloride and acetone were used as crystallizing liquids. Acetone is more powerful in inducing crystallization but the final degree of crystallinity does not depend on the nature of the solvent. The crystalline degree is low as found in the literature for this polymer. This method is very useful to crystallize materials reluctant to thermally induced crystallization such as polycarbonate.

Summary1. The uptake of 3H-digitoxin, 3H-ouabain and 3H-dihydro-ouabain by isolated guinea-pig atria has been studied and compared with the inhibition of the sodium pump and with the inotropic effect.2. Analysis of the curve relating the uptake of digitoxin and ouabain at equilibrium to the bath concentration enabled a non-saturable and a saturable binding site to be distinguished. 3. The uptake of inactive doses of dihydro-ouabain was only by a nonsaturable mechanism. 4. The uptake of labelled digitoxin and ouabain was reduced in the presence of another glycoside. The amount of bound glycoside was nearly equivalent to the estimated non-saturable uptake. 5. The uptake was reduced at 40 C to the clearance of the non-saturable site. 6. ED50 of digitoxin and of ouabain for inhibition of the sodium pump were measured and compared to the ED50 for inotropic effect and to the concentrations producing a half-saturation of the saturable binding site. 7. It is concluded that binding to the saturable site may be responsible for the cardiac actions of the glycosides.

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1. The metabolism of SC-42867 and SC-51089, two PGE2 antagonists, was studied in cultured rat and human hepatocytes. Both compounds possess an 8-chlorodibenzoxazepine moiety, but differ from each other by the nature of the side chain connected to the nitrogen atom. SC-42867 and SC-51089 and their in vitro metabolites were separated by reversed-phase hplc. The major metabolites of both compounds were identified by mass spectrometry (ms) analysis. 2. SC-42867 was metabolized on the tricyclic moiety only. Oxidative N-dealkylation with opening of the oxazepine ring was the major metabolic pathway obtained in rat hepatocytes. The metabolic profile obtained in cultured human hepatocytes was comparable with that of cultured rat hepatocytes. However, the compound was metabolized to a much lower extent by the human cells. 3. SC-51089 was extensively metabolized by both cultured rat and human hepatocytes. Human cells metabolized this compound quite differently than cultured rat hepatocytes. Aromatic hydroxylation with consequent glucuronidation and sulphation were the main metabolic pathways observed in cultured human hepatocytes. Oxidative N-dealkylation with opening of the oxazepine ring and consequent glucuronidation was the major metabolic pathway observed in rat hepatocytes. Further metabolism occurred, in contrast with the human hepatocytes, mainly on the side chain. 4. The present in vitro results are compared with data of previous in vivo studies performed in rat.