Per Johan Sørensen

Effect of Glucocorticosteroids on Some Coagulation Tests

To investigate the influence of glucocorticosteroids on the coagulation system, some coagulation tests were performed before, after 2 days’ and after 6 weeks’ treatment with Prednisone® in 23 patients

Protein C activity in renal disease

Protein C activity was determined in 19 healthy controls and in 52 patients with renal diseases, clinically divided into three groups I) Nephrotic syndrome, II) Renal insufficiency, III) Terminal uremia, requiring maintenance dialysis. In the nephrotic syndrome protein C levels were found to be normal, but in renal insufficiency and terminal uremia the protein C activity was significantly decreased. A correlation between decreasing protein C and progressive renal failure is suggested. The reduced protein C activity may play an important role in the thrombotic tendency seen in renal diseases and uremia.

The effect of n-3 polyunsaturated fatty acids on lipids, haemostasis, neutrophil and monocyte chemotaxis in insulin-dependent diabetes mellitus

Abstract. Insulin‐dependent diabetes mellitus (IDDM) is associated with an increased risk of coronary artery disease (CAD). There is some evidence that polyunsaturated fatty acids of the marine n‐3 type (n‐3 PUFAs) may offer protection against CAD. We have studied the effect of short‐term dietary supplementation with n‐3 PUFAs on lipids, haemostasis, neutrophil and monocyte chemotaxis in 10 patients with IDDM. The patients were given 4 g daily of n‐3 PUFAs (fish oil) for 6 weeks and were investigated before and after the supplement. No significant effects on platelets or haemostasis were observed. High density lipoprotein (HDL)‐cholesterol significantly increased, and triglycerides and the ratio of total cholesterol to HDL‐cholesterol significantly decreased. Monocyte chemotaxis was unaltered, while neutrophil chemotaxis significantly increased after fish oil. The finding of an improvement in neutrophil chemotaxis after supplementation with n‐3 PUFAs to patients with IDDM needs to be confirmed in future studies.

Protein C assays in uremia

Protein C was determined in 42 patients with terminal uremia and 20 healthy controls in three different ways 1) anticoagulant activity 2) amidolytic activity 3) antigen level. Protein C anticoagulant activity was markedly decreased in uremia, but was partly normalized during hemodialysis treatment, whereas the amidolytic activity and antigen level of protein C were normal and without changes during dialysis. The activities and antigen levels of factor II and X were normal before and after hemodialysis. In anticoagulated patients we found a good correlation between prothrombin levels and protein C levels determined with three different assays. We did not find any evidence for a defect carboxylation of protein C as the cause for the defective protein C in uremia. The BaCl2 precipitation in the Protein C anticoagulant assay was incomplete both in uremia and in controls but without differences between the two groups. In vitro addition of urea and creatinine did not decrease protein C activity. The cause of the defective protein C in uremia is still not known but it might contribute to thromboembolic complications.

Cytogenetic studies in patients treated with trimethoprim—sulfamethoxazole

Cytogenetic studies were performed on bone-marrow cells from 12 patients with urinary tract infections treated with trimethoprim-sulfamethoxazole (T + S). An increased number of micronuclei was presented in the patients compared with the control group, whereas structural chromosomal aberrations were not seen. The present study shows that T + S, like other folic acid antagonists, damage the human genetic material, and confirms that the micronucleus test is more sensitive than chromosome analysis in detecting a cytogenetic effect of chemical agents in man.

Effect of human leukocyte interferon on human lymphocytes in vitro: cytogenetic studies

Mitogen-stimulated lymphocytes from 8 healthy donors were exposed to interferon, and cytogenetic studies were preformed. The response of lymphocytes to the mitogens phytohemagglutinin (PHA), concanavalin A (con A) and pokeweed mitogen (PWM) was inhibited by interferon, whereas an increased number of structural chromosomal aberrations was not detected. Further investigations of the cytogenetic effects of interferon are needed.

Protein C in renal allotransplantation during the perioperative period

Abstract Sørensen PJ. Nielsen AH. Knudsen F. Schmitz O. Dyerberg J (Department of Nephrology. and Department of Clinical Chemistry. Aalborg Hospital. Aalborg. and Department of Nephrology. University Hospital of Århus. Århus. Denmark). Protein C in renal allotransplantation during the perioperative period.

Defective Protein C in Uraemia

Protein C activity and antigen levels were determined in 10 haemodialysis patients and 10 healthy controls matched for age and sex. Markedly decreased protein C activity was found whereas protein C antigen level was normal in uraemics. This finding, together with our recent observation that plasma protein C activity is partly normalised during haemodialysis, lead us to suggest the presence of one or more inhibitors of protein C activity in plasma from patients with uraemia.

Low Protein C in Hemodialysis Patients

Protein C activity was studied in 14 hemodialysis patients and compared with 14 healthy, age- and sex-matched controls. Prior to dialysis, protein C activity was depressed in all patients (mean 0.43,

Further Investigations of the Defective Protein C in Hemodialysis, Hemofiltration and Continuous Ambulatory Peritoneal Dialysis

Protein C activity was determined in patients with terminal renal failure treated in three different ways: hemodialysis (n = 20), hemofiltration (n = 7) and continuous ambulatory peritoneal dialysis (n = 7). The protein C activity was decreased in terminal uremia, independent of the kidney replacement therapy employed, compared with 21 normal controls. In the hemodialysis patients protein C activity increased significantly during a hemodialysis treatment, whereas hemofiltration treatment normalized the depressed protein C activity. In vitro experiments with dialysis and with inhibition of normal plasma with ultrafiltrates could not reveal the presence of an inhibitor of protein C in uremic plasma.