Sho Yoshida

Decline of postheparin plasma lipoprotein lipase in acromegalic patients

Lipoprotein lipase and hepatic triglyceride lipase in postheparin plasma were measured in seven patients with active acromegaly by an immunochemical method utilizing antiserum prepared against hepatic triglyceride lipase. A mild or moderate hypertriglyceridemia was shown, with plasma triglyceride concentrations between 156 and 544 mg/dl. Lipoprotein lipase was found to be decreased in all patients (p less than 0.001). Hepatic triglyceride lipase was also low in these patients (p less than 0.001). We speculate that acromegalic hypertriglyceridemia is mediated, at least in part, by the decline in lipoprotein lipase and possibly by the decline in hepatic triglyceride lipase activities.

The Nature of Defects in Quenched α-Brass

The defects such as faulted dislocation loops, perfect dislocation loops and stacking-fault tetrahedra are observed in quenched α-brass. The faulted loops lie on the {111} planes and have various polygonal shapes with edges along the directions. The perfect loops have hexagonal, rhombic and irregular shapes, and the former two are on the {111} planes with their edges along the directions. Analysis of the image contrast reveals that the faulted loops are of the vacancy type having a Burgers vector a/3 and the perfect loops are of the vacancy type having a Burgers vector a/2 . The perfect loops are favoured when the quenching temperature is high, while the faulted loops are favoured when the temperature is low. The stacking-fault tetrahedra are occasionally observed by high temperature quenching. The formation energy of a vacancy is estimated to be about (1.00±0.05) eV from the density and size of observed loops. The formation of three different defects is discussed by the simple energy comparison.