Fifty-two patients with sickle-cell (SC) disease (48 with SC-beta-thalassaemia and 4 with homozygous SC-anaemia) were studied as regards blood coagulation and fibrinolysis. It was found that the thrombin and the reptilase times of the patients' plasma were significantly shorter than normal. The mean values of platelet count, fibrinogen level and factor VIII activity of patients with SC disease were higher than normal; however, in the group of patients transfused, with less than 50% haemoglobin S (HbS), the fibrinogen level and the factor VIII activity were significantly lower compared to the other patients. Antithrombin-III (At-III) activity was normal in all. The fibrinolytic activity was normal in patients with asymptomatic SC disease, but reduced in patients on painful crises. Plasminogen and fibrinogen/fibrin degradation product (FDP) levels were normal in all patients. Two patients on painful crises with complications had additional abnormal findings, namely prolonged prothrombin time, reduced At-III level and elevated FDP.
Transport properties of membrane vesicles isolated from two adenosine triphosphatase-deficient mutants of Escherichia coli, NR70 and DL54, were compared with those of vesicles prepared from the corresponding parental strains. As reported previously (Rosen, 1973; Altendorf et al., 1974), vesicles prepared from these mutants grown under aerobic conditions exhibited defective amino acid transport, and activity was restored after treatment with dicyclohexylcarbodiimide. In sharp contrast, however, vesicles isolated from the same mutants grown anaerobically in the presence of nitrate exhibited completely normal transport activity when assayed under either anaerobic or aerobic conditions. Suppression of the transport defect was not due to the manner by which the vesicles were prepared, and the adenosine triphosphatase deficiency was not ameliorated by anaerobic growth in the presence of nitrite. Finally, the transport activity of vesicles prepared from the mutants grown under aerobic conditions was relatively resistant to the effect of 1.0 M guanidine hydrochloride extraction, whereas the activity of vesicles prepared from mutants grown anaerobically was totally refractory to the effect of the chaotrope.