摘要:

The mean levels of fibrinopeptide A (FPA), thrombin-antithrombin complex (TAT), and soluble fibrin (tPA method) in cancer patients (n = 32) were intermediate between those of patients with cerebral infarction and pancreatitis who had the most abnormal results and patients with myocardial infarction and pneumonia who had the least abnormal results. Patients with disseminated malignancies (n = 16) had significantly higher mean levels of FPA (10.6 vs. 5.3 nmol/l) and TAT (11.0 vs. 4.4 pmol/l) than patients with limited malignancies (n = 16). The difference in soluble fibrin (fibrin monomer, FM; 22.1 vs. 18.0 nmol/l) was not significant. The values of FPA, FM, and TAT in the patient population correlated significantly. There was a negative correlation between the level of antithrombin and test results for FPA (-0.69), FM (-0.48), and TAT (-0.38) in the cancer patients. Even cancer patients with locally limited disease may have elevated FPA, FM, and TAT test results, indicating a state of definite hypercoagulation.

ISSN:1424-8832    

DOI:10.1159/000216136

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

One hundred and fourty-eight insulin-dependent diabetic patients were available for this study; 56 males and 92 females. For the investigation of coagulation activation we determined activated partial thromboplastin time, thrombin time, and fibrinogen besides fibrin monomers and thrombin-antithrombin III complexes (TAT-III). We assessed large percentages of increased fibrinogen levels but non-significant increases of the mean values in comparison with the reference group. The values for thrombin time were significantly prolonged, although relatively small percentages were exceeding the reference range. For the activated partial thromboplastin time, the values exceeded the upper reference limit, and the mean values were significantly higher than those of the reference group. Also for the fibrin monomers we obtained often enhanced values, and, moreover, the values were significantly higher as compared with the reference subjects. The amount of TAT-III concentrations above the reference range was much smaller than for the fibrin monomers and the TAT-III levels were not significantly enhanced. The results presented here are indicative of coagulation activation in diabetics, as indicated by the fibrin monomers and more or less by the TAT-III levels. Moreover, there could be demonstrated a positive correlation between fibrin monomer levels and HbA1 concentrations.

ISSN:1424-8832    

DOI:10.1159/000216137

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Twenty-six healthy volunteers were given the non-steroidal anti-inflammatory drug nabumetone (1 g/day p.o.) for 10 days. Platelet aggregation tests in response to adenosine diphosphate, adrenaline, collagen, arachidonic acid, and ristocetin and bleeding time and coagulation screening tests were performed on three occasions: (1) before drug therapy; (2) on the last day of drug therapy, and (3) 5 days after the end of therapy. No significant changes were noted in platelet aggregation, bleeding time, or the coagulation screening tests, except for a significant drop in fibrinogen during therapy and for 1 week after stopping the drug. The lack of any antiplatelet action and minimal effects on the coagulation parameters recommend the drug as a suitable antirheumatic in patients with bleeding disorders. The hypofibrinogenaemic action requires further studies.

ISSN:1424-8832    

DOI:10.1159/000216138

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

A chromogenic factor IX assay is developed which requires only two time-dependent steps. Diluted plasma is mixed with a reagent containing factors VIII and X. The reaction is started by addition of a reagent containing factor XIa, thrombin, CaCl2, and phospholipids. Then factor XIa activates factor IX if present, thrombin activates factor VIII, and subsequently the complete factor X activating complex (factor IXa, factor VIIIa, Ca ions, and phospholipids) rapidly activates factor X. Finally, ethylenediaminetetraacetic acid plus a chromogenic substrate are added to stop the reaction and to measure formed factor Xa. Factor Xa formation is proportional to the plasma factor IX concentration (from 0 to 140%). The two reagents needed for the assay are stable at room temperature during a whole working day and for 3 h at 37 °C. A new isolation procedure for factor VIII is described. Factor VIII is purified from bovine plasma in a few steps with a yield of 20% and a 8,000-fold purification

ISSN:1424-8832    

DOI:10.1159/000216139

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Porcine or bovine factor VIII concentrates (FVIIl·C) have been used during the past 3 decades to control bleeding in patients who have developed antibodies to human factor VIII. Since current preparations of animal FVIIl·C are not known to transmit infectious agents such as hepatitis or human immunodeficiency virus, they are of potential therapeutic interest. A purified porcine FVIIl·C (Hyate:C) is now widely used as an alternative to human FVIIl·C in patients with inhibitor. Unlike earlier preparations of porcine FVIIl·C, thrombocytopaenia is rare with the current preparation. Nonetheless, it causes the aggregation of human platelets in vitro. Our aim was to identify precisely the plasma factor which induces platelet aggregation. The effects of commercial porcine FVIIl·C, porcine fibrinogen, porcine fibronectin and the corresponding preparations from human origin on platelet aggregation were studied. Platelet aggregation was quantified by measuring the fall in single platelet count in human whole blood. Of these preparations, only porcine FVIIl·C (0.1–1 U/ml) and porcine fibrinogen (80–600 μg/ml) induced a fall in single platelet count of up to 85% due to aggregation. The extent of aggregation was directly proportional to the amount (0.007–0.1 U/ml test aliquot) of residual von Willebrand factor antigen (vWl·Ag) in the preparations. A monoclonal antibody to vWl·Ag inhibited the aggregation. We believe that the aggregation of human platelets induced in vitro by porcine FVIIl·C is mediated by vWl·Ag which also may be responsible for thrombocytopaenia reported following administration of porcin

ISSN:1424-8832    

DOI:10.1159/000216140

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Cerastobin, a thrombinlike enzyme with arginine esterase activity, was purified from crude Cerastes vipera (Egyptian Sahara snake) venom. Unlike thrombinlike enzymes isolated from other snake venoms, cerastobin had a potent platelet aggregatory effect. The activation of human platelets was not related to adenosine diphosphate release and/or prostaglandin synthesis. Cerastobin showed a proteolytic activity towards protein constituents of the platelets’ cytoskeleton. It hydrolyzed actin, actin-binding protein, and P235. This may explain at least a part of the aggregatory mechanism(s) of cerastobin. Electron microscopic studies of the stimulated platelets revealed changes in their morphology, including the appearance of pseudopodia, dilatation of the canalicular system with the formation of peripheral balloons, and centralization of the platelet organelles. Some inhibitors of the esteratic activity of cerastobin also inhibited its ability to aggregate platelet

ISSN:1424-8832    

DOI:10.1159/000216141

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

As depressed fibrinolysis is implicated in the pathogenesis of coronary artery disease, we have studied the activation of fibrinolysis during maximal, symptom-limited exercise in a group of 68 men. After exercise they were divided, according to their coronary angiography and exercise 201T1 emission computed tomography results, into three groups. Group 1: persons with normal exercise 201T1 emission computed tomography results and no underlying diseases who served as controls; group 2: patients with coronary artery disease without exercise-induced myocardial ischemia, and group 3: patients with coronary artery disease with transient, exercise-induced myocardial ischemia. Before and at peak exercise we measured the plasminogen activator activity (PAA) in the euglobulin fraction of plasma by an amidolytic method and the concentrations of tissue plasminogen activator (t-PA), activator-inhibitor complex – plasminogen activator inhibitor 1 (PAI-1) complexed with t-PA -and total PAI-1 by enzyme immunoassay. The concentration of free PAI-1 in plasma was calculated by subtraction of the concentration of activator-inhibitor complex from that of total PAI-1. Under basal conditions, group 3 had significantly higher free and total PAI-1 levels than group 1. There were no statistically significant differences between the three groups in PAA, t-PA, and activator-inhibitor complex levels. At peak exercise, group 1 showed the highest release of t-PA accompanied with highest increases in PAA as well as in activator-inhibitor complex, the proportion of released t-PA antigen not bound to PAI-1 being highest in group 1. Free PAI-1 decreased significantly, but there were no differences between individual groups. Our results indicate that increased PAI-1 levels in plasma and decreased release of t-PA from endothelial stores play a role in impairment of fibrinolysis in coronary artery disease. These disturbances are more pronounced in patients who develop myocardial ischemia during exercis

ISSN:1424-8832    

DOI:10.1159/000216142

出版商:S. Karger AG    

年代:1990

数据来源: Karger