Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0149871 (deep vein thrombosis)
 12,364 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Activation of prothrombin and the subsequent reactions of thrombin with its substrates and its major inhibitors, antithrombin III (AT III) and heparin cofactor II (HC II), likely reflect both intravascular and extravascular coagulation. Several studies have reported increased in vivo coagulation in cancer. Whether the increased thrombin production in malignancy is accompanied by a corresponding increase in thrombin inhibition is unknown. This study quantified prothrombin fragment 1 + 2 (F1 + 2), thrombin-AT III (TAT), thrombin-AT III-vitronectin (TAT.V), and thrombin-HC II-vitronectin (THCII.V) in the plasmas of healthy volunteers (n = 37); patients with localized solid tumours before treatment was initiated (n = 39); and five patients with non-Hodgkin's lymphoma, both before and during weekly chemotherapy. Two of the five non-Hodgkin's lymphoma patients developed deep venous thrombosis (DVT) during chemotherapy. In normal plasma, where the concentrations of the four parameters likely reflect haemostasis, the sum of TAT, TAT.V and THCII.V was 61% that of F1 + 2, compared with 30% in cancer plasmas. In addition, the mean +/- SEM of F1 + 2 in the plasmas of cancer patients (1.56 +/- 0.09 nM) was significantly elevated (P < 0.001) when compared with healthy volunteers (0.89 +/- 0.06 nM). Eight weeks of chemotherapy increased the F1 + 2 and the binary TAT in plasmas of the non-Hodgkin's lymphoma patients by approximately 1.5- and 2.9-fold, respectively. Thus, increased prothrombin activation in cancer patients, without corresponding increases in concentrations of thrombin-inhibitor complexes, raise the possibility that a significant portion of the thrombin generated in vivo escapes inhibition in cancer and contributes to the high risk of DVT in malignancy.
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PMID:The hypercoagulable state in cancer patients: evidence for impaired thrombin inhibitions. 751 51

The activation of the clotting cascade leading to deep venous thrombosis begins during total hip arthroplasty, but few studies have assessed changes in coagulation during surgery. A better understanding of thrombogenesis during total hip arthroplasty may provide a more rational basis for treatment. In 3 separate studies, the following observations were made. Circulating indices of thrombosis and fibrinolysis: prothrombin F1.2, thrombin-antithrombin complexes, fibrinopeptide A, and D-dimer, did not increase during osteotomy of the neck of the femur or during insertion of the acetabular component, but rose significantly during insertion of the femoral component. Thrombin-antithrombin complexes, fibrinopeptide A, and D-dimer were higher after insertion of a cemented component than insertion of a noncemented femoral component. A significant decline in central venous oxygen tension was observed after relocation of the hip joint and after insertions of cemented and noncemented femoral components, providing evidence of femoral venous occlusion during insertion of the femoral component. In patients receiving a cemented femoral component, mean pulmonary artery pressure increased after relocation of the hip joint, indicating intraoperative pulmonary embolism. No changes in mean pulmonary artery pressure were noted with noncemented total hip arthroplasty. Administration of 1000 units of unfractionated heparin before insertion of a cemented femoral component blunted the rise of fibrinopeptide A. The results of these studies suggest that (1) the greatest risk of activation of the clotting cascade during total hip arthroplasty occurs during insertion of the femoral component; (2) femoral venous occlusion and use of cemented components are factors in thrombogenesis during total hip arthroplasty; and (3) measures to prevent deep venous thrombosis during total hip arthroplasty (such as intraoperative anticoagulation) should begin during surgery rather than during the postoperative period and be applied during insertion of the femoral component.
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PMID:The John Charnley Award. Thrombogenesis during total hip arthroplasty. 755 26

Various experimental models have been developed in order to more clearly understand deep vein thrombosis, the mechanisms involved and its treatment. These models are based on venous stasis, either alone or combined with the injection of thrombogenic substances or endothelial lesions. Other models only use endothelial lesions. Thrombogenic substances are mostly composed of activated factor X or thrombin, which raises the problem of purity of the substances and determination of the antithrombotic activities of the substance tested, especially heparin and hirudin and their derivatives, and consequently their efficacy. Endothelial lesions can be induced by chemical, physical or electrical agents or by repeated application of clamps, or cellular crushing. These models result in the formation of various forms of venous thrombus. The development and improvement of experimental models is very important in every case. Experimental models of thrombosis constitute the best tool for the study of thrombosis, in which many points remain to be elucidated. They also allow the study and development of various antithrombotic substances the improvement of their efficacy. These models must be validated, standardized, reproductible and in agreement with local legislation in each country.
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PMID:[Experimental models of venous thrombosis]. 757 61

A 70-year-old woman on maintenance hemodialysis for 3 years was admitted to our hospital because of deep vein thrombosis (DVT) in the right femoral vein. Seven days before admission, she suddenly noticed severe pain in her right inguinal region while she was walking on the street. A wide range of stenosis from the iliac to the distal femoral region was detected by both CT scanning and venography. Her hematocrit reading was 30% and her serum erythropoietin level was 10.5 MU/ml, which was within the normal range, on the day of admission. The results of routine coagulation tests, including prothrombin time, activated partial thrombin time and plasma fibrinogen values, were normal. Plasma anti-thrombin III and plasminogen were also normal. In contrast, beta-thromboglobulin, platelet factor IV, fibrinogen degradation product, D-dimer, thrombin-antithrombin III complex (TAT) and fibrinopeptide A were abnormally elevated. In the venous occlusion test which was performed in the forearm of the opposite side of the arterio-venous shunt, plasma tissue type plas-minogen activator values showed little response to occlusion indicating that the vessel endothelium may have been partially damaged. These data suggest that the DVT had been induced by imbalance of increased blood coagulation and decreased fibrinolytic activity. Damaged vascular wall may also have contributed to the production of DVT. Furthermore, it is surprising that the patient had elevated values of D-dimer and TAT for many years without recurrence of the DVT. Spontaneous DVT in an apparently healthy individual on maintenance hemodialysis seems to be rare, compared with arterial thrombosis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[A long-term hemodialysis patient with spontaneous deep vein thrombosis, showing high levels of coagulo-fibrinolytic markers]. 760 31

Recombinant hirudin is currently being developed as a potential prophylactic and therapeutic antithrombotic drug in various clinical indications such as angina and deep venous thrombosis. In this report, we have discussed the production of specific polyclonal antibodies to recombinant hirudin (rH) and the development of two ELISA methods to measure rH concentrations in biological fluids: a sandwich and a competitive ELISA method. Intra- and inter-assay variations in the two methods are extremely low (3-7%). The competitive ELISA method is rapid, simple and highly reproducible. Saturation binding curves, selection of appropriate incubation times, recovery of different hirudin variants and reactivity in the presence of thrombin are discussed. The methods can be easily adapted to monitor hirudin concentrations in the clinical laboratory for diagnostic purposes as well as for performing pharmacokinetic studies.
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PMID:Development and validation of two enzyme-linked immunosorbent assay (ELISA) methods for recombinant hirudin. 766 Jan 41

Dermatan sulphate catalyses thrombin inhibition by heparin cofactor II; it has a lower haemorrhagic to antithrombotic ratio than that of heparin in animal models. Consecutive patients aged forty years or more, electively undergoing total hip replacement under general anaesthesia, were randomly allocated to one of three dosage regimens of dermatan sulphate (MF701, Mediolanum Farmaceutici) given intramuscularly. These were 200 mg once daily (n = 50), 200 mg twice daily (n = 52) and 300 mg twice daily (n = 51), administered from twenty-four hours pre-operatively until the tenth postoperative day. The overall incidence of DVT assessed by bilateral venography was 53%, 51% and 34% respectively (Chi-square test for trend p = 0.06). The incidence of major proximal DVT was 10.6%, 8.5% and 2.1% respectively. Pulmonary embolism (PE) and bleeding were assessed in all 153 patients. There was one case of PE in each dose group. The incidence of bleeding episodes, volume of blood lost and blood transfusion requirements were low and showed no increase with increasing dose. The patients were followed up 4-8 weeks after discharge. We conclude that the two lower doses were subtherapeutic in this population, however dermatan sulphate given 300 mg twice daily, proved to be efficacious with an incidence of proximal major DVT of 2.1% and a low incidence of bleeding complications. A trial of dermatan sulphate 300 mg twice daily compared to standard prophylactic agents is needed.
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PMID:A dose ranging study to evaluate dermatan sulphate in preventing deep vein thrombosis following total hip arthroplasty. 774 Apr 43

The physiologic mechanisms that protect children from thromboembolic complications are not known. We investigated the regulation of thrombin in children because of its central importance to thrombosis. The capacity to generate thrombin in vitro (chromogenic assay) was decreased by 26% in plasmas from children (1-16 yrs; n = 102) compared to adults ([20-45 yrs; n = 20; p < 0.001]). The addition of purified prothrombin to plasmas from children increased thrombin generation to adult values. The capacity of plasmas to inhibit 125I-alpha-thrombin was increased by 21% in children compared to adults (p = 0.020), with significantly more thrombin complexed to alpha 2-macroglobulin (alpha 2M) in children. When DVT occur in children, adult guidelines for heparin therapy are used. At low heparin concentrations (0.1 and 0.2 U/ml), thrombin generation was decreased by 30% in children compared to adults (p < 0.001). At high heparin levels (0.4 U/ml), thrombin generation was negligible in all plasmas. ATIII inhibited over 95% of thrombin in all plasmas in the presence of heparin. In summary, thrombin regulation differs in children from adults and may protect children from thromboembolic complications. When DVT do occur, heparin requirements may differ in children compared to adults.
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PMID:Thrombin regulation in children differs from adults in the absence and presence of heparin. 774 Apr 51

Abnormal antithrombin III (AT III) was found in a 30-year-old woman who suffered from recurrent thrombosis during pregnancy and the postpartum period. Among her family members, only her father had recurrent episodes of deep vein thrombosis of the lower extremities, from his youth. The antithrombin and antifactor Xa heparin cofactor activities of the proposita's plasma were 61% and 42% of normal, respectively. The progressive antithrombin and antifactor Xa activities were also decreased to 55% and 58% of normal, respectively. The immunoreactive level of AT III was within the normal range (23.1 mg/dl). Analysis of the proposita's plasma by crossed immunoelectrophoresis in the presence or absence of heparin and by affinity chromatography on heparin-Sepharose revealed that the proposita's AT III had apparently normal affinity for heparin. Nucleotide sequencing of 7 exons of the proposita's AT III gene amplified by polymerase chain reaction (PCR) disclosed that the second base of codon 393 comprised both G and A, indicating Arg393-His conversion. The base sequences of exons 1, 2, 3a, 3b, 4, and 5 were normal, excluding any other mutation. These findings indicated that the proposita's AT III was a variant of AT III at the thrombin binding site and that the proposita was a heterozygote for the abnormality. Heparin affinity of purified abnormal AT III from the proposita's plasma was demonstrated to be increased upon affinity chromatography using heparin-Sepharose, suggesting that the mutation (Arg393-His) per se could possibly increase the affinity of antithrombin III for heparin. For this variant AT III (Arg393-His), the name AT III Kumamoto II is proposed.
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PMID:Antithrombin III Kumamoto II; a single mutation at Arg393-His increased the affinity of antithrombin III for heparin. 783 87

In order to evaluate the usefulness of determining D-dimer and thrombin-antithrombin III complex (TAT) in the diagnosis of deep venous thrombosis (DVT), three D-dimer assays were tried: one ELISA and one latex test from Diagnostica Stago and one new latex method from Biopool. TAT was assessed using an ELISA (Behringwerke). We studied 96 consecutive outpatients with suspected DVT, of whom 36 had phlebographically confirmed DVT. Statistical calculations showed high sensitivity and a negative predictive value for the D-dimer ELISA (97% for both), confirming the results obtained by others. The new latex method (Biopool) showed similar figures (96% for both). The latex method from Diagnostica Stago and TAT showed lower sensitivity and negative predictive values. No differences in the D-dimer results were found with or without antifibrinolytics in the tubes for blood sampling. Our data suggest that negative results when using the new simple and cheap latex method (Biopool) may reduce the number of phlebographic examinations.
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PMID:D-dimer and thrombin/antithrombin III complex--diagnostic tools in deep venous thrombosis? 784 46

Treatment monitoring based on a laboratory parameter increases the efficacy and safety of standard heparin therapy, but it is not known if this also applies to low-molecular-weight heparin (LMWH) therapy of acute deep vein thrombosis (DVT). In a prospective randomized trial involving 122 consecutive patients, group A (58 patients) received a weight adjusted dose of Fragmin (100 IU/kg) subcutaneously twice a day throughout the treatment period (10 days +/- 1), while in group B (64 patients) the dosage was based on the results of an anti factor Xa (anti Xa) amidolytic assay to obtain a target concentration from 0.5 to 1 IU/ml. AntiXa and antithrombin activities were also measured retrospectively on frozen plasma from all patients. The two regimens were comparable in terms of hemorrhagic complications (4 in group A and 3 in group B). Bilateral ascending phlebography was performed before inclusion and at the end of LMWH treatment. Treatment efficacy, based on Marder's score, did not differ between the two groups (p = 0.3). Dosage adjustment to between 0.5 to 1 IU anti-Xa/ml does not therefore appear to improve the efficacy or safety of LMWH treatment. However, correlations between the change in Marder's score and both anti-Xa (p < 0.001) and antithrombin activity (p < 0.001) were observed, suggesting a relationship between the degree of FXa or thrombin inhibition and antithrombotic activity.
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PMID:Adjusted versus fixed doses of the low-molecular-weight heparin fragmin in the treatment of deep vein thrombosis. Fragmin-Study Group. 797 34


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