[Aortocoronary bypass surgery at Tygerberg Hospital, 1978 - 1980]. / Aortokoronêre omleidingschirurgie te Tygerberg-hospitaal, 1978-1980.

Between January 1978 and December 1980. 118 patients underwent saphenous vein bypass surgery for obstructive coronary artery disease at Tygerberg Hospital. Sixteen patients in addition to bypass surgery underwent mitral and/or aortic valve replacement or resection of a ventricular aneurysm. The operative and hospital mortality was 3,0% (4/134) for all patients and 3,3% (4/118) for patients who had aortocoronary bypass surgery as the sole procedure. Follow-up of the surviving patients for a mean period of 16,4 months revealed a low incidence of late myocardial infarction of 3.6% (4/112) resulting in the death of only 1 patient; 89.1% of patients were free of angina pectoris and the majority of these resumed their normal work or enjoyed their retirement.

Studies on the ultrastructure of blood cells and the microaggregate fraction in stored human blood.

Electron microscopy of citrate-phosphate-dextrose (CPD) buffered bank blood performed over 21 days shows that the normal architecture of erythrocytes, platelets and leucocytes disappears and that deformed organelles, leucocyte "ghosts", cell fragments and microaggregates accumulate. Leucocytes and platelets emerge as the most sensitive indicators of blood deterioration showing profound morphological changes from the first day. Microaggregates which passed through a 20-micrometer high capacity transfusion filter were identified as platelet conglomerates, leucocyte "ghost" and platelet-leucocyte "ghost" coaggregates with diameters of 6--20, 20--30 and 30--40 micrometers respectively. Of these aggregates present in the filtrate, 62% fell into the size range of 20--40 micrometers. The composition of microaggregates varies with storage time, the platelet conglomerates appear first during or after Day 1, leucocyte "ghosts" after Day 5 followed by platelet-leucocyte "ghost" coaggregate formation. At this stage the number of intact leucocytes and platelets is reduced and the filtrate shows an abundance of leucocyte debris. Microfiltration would thus appear to reduce but not eliminate the danger of microembolism and damage to capillary endothelium.

[A new method of measuring serotonin in plasma and cerebrospinal fluid]. / 'n Nuwe metode vir die bepaling van serotonien in bloed en serebrospinale vloeistof.

A new rapid method for the microdetermination of serotonin (5-hydroxytryptamine) in plasma and cerebrospinal fluid is described. A recovery coefficient of 98% was obtained in the present method, with the use of [3H]-hydroxytryptamine creatinine sulphate as an internal standard, compared with recovery coefficients of 31% and 66% for the two existing methods generally used for serotonin determination. This method involves a one-step sample deproteinization by perchloric acid, resulting in a high stability of serotonin.