摘要:

Low-density lipoprotein (LDL) adsorption using a dextran sulfate cellulose column is brought about by electrostatic binding between the positive charges of apolipoprotein B in LDL and the negative charges of dextran sulfate cellulose. There is general agreement that the initial contact phase in the coagulation pathway may be activated by a negatively charged surface such as dextran sulfate cellulose, resulting in the generation of bradykinin. We investigated whether the increase in the generation of bradykinin during LDL adsorption is accompanied by the activation of endogenous production of nitric oxide (NO) in patients with peripheral atherosclerosis. LDL adsorption therapy was repeated ten times over a period of 3 months in ten peripheral atherosclerosis patients. Treatment significantly reduced serum total cholesterol and LDL cholesterol levels. This was associated with a significant improvement in Fontaine's classification and ankle pressure index. We also measured the kinin-kallikrein system and plasma levels of NO in the same patients. The results showed that coagulation factors of the intrinsic pathway including high-molecular-weight kininogen and prekallikrein decreased markedly after initial adsorption compared with the levels before treatment. There was a marked increase in bradykinin and NO concentrations after the initial adsorption, compared with their levels before adsorption. Our results suggest that the generation of bradykinin and increased plasma levels of NO may contribute to the improvement in peripheral circulation after LDL adsorption in peripheral atherosclerosis patients.

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Fibrinogen Caracas I is a dysfibrinogenemia with a mild bleeding diathesis and a defective wound healing. We have characterized this abnormal fibrinogen using transmission electron microscopy (TEM) in combination with turbidity and permeation studies. Turbidometric and permeability analysis showed that the abnormal fibrin had a significantly decreased mass: length ratio and fiber diameter. In addition, the permeability studies of plasma fibrin clots showed that the gel porosity of the abnormal fibrinogen was reduced. Images of the abnormal fibrin structure obtained using TEM showed that the fibers were thinner, much less branched and less ordered than normal fibers. Diminished fibrin fiber diameter and reduced fibrin gel porosity have been taken as hallmarks of thrombophilic dysfibrinogenemias. The results of the present study show that these features are not necessarily predictive of thrombophilia. Further studies performed on a larger number of dysfibrinogenemias need to be conducted in order to establish the implications of these parameters on the clinical outcome.

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Vitamin K antagonists are most commonly used in long-term thrombosis prophylaxis and the use in patients with cardiovascular disease seems to be increasing. By interfering with the normal hemostatic mechanism, an increased risk of bleeding will arise and administration of human plasma or prothrombin complex concentrates may be necessary. It can be difficult to normalize hemostasis using plasma and prothrombin complex concentrates, because these may be associated with thromboembolic side-effects. The level of factor VII, one of the vitamin-K-dependent coagulation factors, decreases during oral anticoagulant therapy and the administration of recombinant factor Vila normalizes the prolonged prothrombin time in warfarin-treated rats. After administration of acenocoumarol (International Normalized Ratio > 2), decreased levels of factor X and factor IX (19–46%), protein C (2–20%) and factor VII (4–17%) were found in 28 healthy volunteers. After one dose of recombinant factor Vila (5, 10, 20, 40, 80, 120, 160, 240, or 320 μg/kg) the International Normalized Ratio and prothrombin time normalized, which may imply an effect on bleeding in individuals receiving oral anticoagulant therapy. The lowest dose (5μg/kg) normalized the International Normalized Ratio for 12 h and doses > 120 μg/kg normalized it for 24 h. Fragment 1+2 stayed within its normal range in all dose groups, indicating that no systemic coagulation occurred.

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Plasma D-dimer, a highly sensitive marker of venous thromboembolism, was measured using an enzyme-linked immunosorbent assay pre-operatively, on the third postoperative day, and at the time of phlebography in 118 patients undergoing elective total knee arthroplasty. Deep venous thrombosis (DVT) was detected using systematic bilateral phlebography between the eighth and 12th postoperative day in 47 (39.8%) patients. D-dimer plasma concentrations did not differ between patients who had DVT and those who had no DVT, either pre-operatively (n= 118,P= 0.63) or at the time of phlebography (n= 111,P= 0.70). On the third postoperative day, D-dimer concentration was significantly higher (P< 0.01) in the patients who had DVT (median 3270 μg/l, range 1156–9996,n= 47) than in those who did not (2287 μg/l, 685–7062,n= 64). However, receiver operating characteristics curve analysis did not provide any useful cutoff values that would allow individual diagnoses to be made. In conclusion, the results of the present study suggest that plasma measurement of D-dimer concentration is of no value for predicting, diagnosing or ruling out DVT in patients undergoing total knee arthroplasty.

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

We report a 22-year-old man who successfully underwent coronary stent implantation after an acute myocardial infarction. Lupus anticoagulant and antibodies against cardiolipin and prothrombin were detected despite the absence of any underlying disease. Therefore, long-term oral anticoagulation was instituted and appeared to be effective. To our knowledge this is the first report on coronary stenting in primary antiphospholipid syndrome.

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

We report a patient who had an ischemic stroke aged 22 years, an inherited type I protein C deficiency and a heterozygous genotype of prothrombin gene 20210A. In view of recent reports of an increased risk for ischemic cerebral vascular disease in patients with the prothrombin 20210A mutation, we suggest that many of the reported cases of ischemic stroke and protein C deficiency may have had additional prothrombotic disorders such as the prothrombin mutation. The current data concerning the magnified risk for stroke in patients with the prothrombin 20210A mutation suggests the need to study all patients with premature stroke for this mutation and the other risk factors for thrombosis. This would include homocysteine, lupus inhibitor, anticardiolipin antibodies, and possibly the natural inhibitors of coagulation. It is possible that patients with the prothrombin 20210A mutation and ischemic cerebral vascular disease would benefit from long-term anticoagulation therapy in a similar way to patients with the antiphospholipid syndrome.

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Hypoprothrombinemia is a rare hereditary coagulation defect characterized by low levels of biologically active prothrombin. In this paper we report the laboratory and genetic analysis of a patient with a severe hypoprothrombinemia and some of her relatives. Laboratory analysis showed very low levels of prothrombin antigen. Molecular analysis of the prothrombin genes of the patient resulted in the identification of two novel sequence variations in heterozygous state, a 20079 G to A transition, which predicts a Trp 569→Stop mutation, and a 1261C→G change within intron B near the acceptor splice site. A cosegregation of prothrombin deficiency in family members with the two genetic defects was observed.

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:0957-5235    

出版商:OVID    

年代:1998

数据来源: OVID