Search PubMed⌕ Search

Biomedical subjects

A L Bloom

Publications and source records attributed to A L Bloom.

At least 127 records · Page 7Linked to original sources
PubMed1972

A clinical and experimental study of platelet function in chronic renal failure.

Coagulation and platelet function studies were performed on 24 normal subjects and 29 patients with chronic renal failure due to various causes. Thrombocytopenia was uncommon in the uraemic patients but there was reduced platelet retention in glass bead columns and platelet aggregation with adenosine diphosphate (ADP) and thrombin was slower and less complete than normal. The rate of platelet disaggregation in uraemic patients was significantly reduced. The abnormalities tended to be more severe in more uraemic subjects. In normal subjects no inter-relationships were observed between the various measurements of platelet activity. In patients there were significant interrelationships between the measurements of platelet aggregation with ADP and thrombin and between the measurements of aggregation and retention in glass bead columns. It is suggested that if a common pathway is involved in these reactions it is adversely affected in uraemia. Plasma coagulation defects were uncommon and present in only five of the uraemic subjects. Impaired prothrombin consumption apparently due to defective platelet function was present in half the patients but was not detected by a kaolin activation method. Although platelet coagulation function was activated during ADP aggregation and disaggregation in normal and uraemic subjects, it did not correlate in the latter with impairment of aggregation. It is suggested that aggregation and activation of platelet coagulant activity are not necessarily related aspects of platelet function. An effect of uraemic plasma on normal platelets was demonstrated by mixing experiments consistent with a humoral cause for the uraemic platelet defects.

Adenosine Diphosphate↗
PubMed1971

Coagulation studies in haemophilic patients taking oral contraceptives.

Coagulation studies were performed on haemophilic patients during a controlled trial of oral contraceptive therapy. Treatment with a combined oestrogen-progestogen preparation was associated with a significant rise in the factor VII-X complex. This change was not observed during treatment with progestogen alone. The highest levels of factor IX and fibrinogen and the lowest levels of factor X were observed during the first period of the trial but these effects were independent of the type of treatment. The results suggest that the effects of oral contraceptives on blood coagulation in haemophilic males are similar to those observed in normal females and that the changes are due to the oestrogenic component.

Analysis of Variance↗
PubMed1971

A study of two methods for estimating plasma fibrinogen and the effect of epsilon aminocaproic acid and protamine.

Fibrinogen concentrations were determined in normal plasma and in plasma from patients with high and low levels. There was a good correlation between the results of a rapid semi-quantitative fibrinogen titre technique and those of a quantitative assay of coagulable fibrinogen. In normal subjects fibrinogen levels were not significantly influenced by taking blood into epsilon aminocaproic acid (EACA) or by the addition of protamine to plasma. In patients with the defibrination syndrome in whom increased plasma fibrinolysis was not detected, fibrinogen levels were not affected by taking blood into EACA but considerably increased levels were observed after the addition of protamine to plasma. In patients undergoing thrombolytic therapy the fibrinogen levels measured were increased both in blood taken into EACA and in plasma containing protamine. It is suggested that EACA acted by preventing lysis in vitro whilst protamine counteracted abnormal fibrin polymerization. The pattern of results may be of diagnostic importance.

Aminocaproates↗
PubMed1969

Comparison of qucik and slow thaw methods of producing cryoprecipitate antihaemophilic factor from fresh and 24-hour-old blood.

Cryoprecipitate antihaemophilic factor concentrate was prepared from fresh and 24-hour-old blood by quick and slow thaw methods. Recovery of factor VIII was greater by the slow thaw method and there was less loss into the supernatant plasma. Cryoprecipitate produced from fresh blood contained more factor VIII than that produced from 24-hour-old blood so that the most potent concentrate was produced from fresh blood by the slow thaw process. An adequate therapeutic preparation was, however, produced by the slow thaw method using 24-hour-old blood and it is suggested that this procedure could be adopted in order to supplement supplies.

Blood↗