Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thrombosis occurs when there is a breakdown in the balance between thrombogenic factors and protective mechanisms. The thrombogenic factors may be exogenous (e.g. trauma, surgery), endogenous (e.g. cancer, vascular diseases) or both (e.g. atherosclerosis, complicated pregnancy). Defects in the protective mechanisms may be congenital (e.g. factor V R506Q-mutation, deficiency of protein C, protein S or antithrombin) or acquired (e.g. lupus anticoagulans, deficiency of antithrombin in nephrosis). In recent years, research in thromboembolic diseases has been overwhelmed with new observations, rendering it worthwhile to put efforts into the evaluation of thrombotic mechanisms in individuals suffering from or predisposed to thromboembolic diseases. Such efforts will pave the way for more effective prophylaxis in thrombosis-prone patients, more specific treatment of thrombotic diseases, and the mastering of recurrent thrombosis.
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PMID:Thrombogenesis. 868 75

The aim of this study was to examine whether there was a relationship between ultrasound-assessed morphology of the femoral artery wall and hemostatic factors, and whether these factors were associated with intermittent claudication. One hundred and thirty men at high cardiovascular risk and 51 men at low risk were examined. The subjects (high- and low-risk) with moderate/large plaque (n = 96) had higher fibrinogen, thrombin/antithrombin complex and von Willebrand factor, compared to subjects with small/no plaque. The maximum intima-media thickness of the femoral artery was significantly associated with fibrinogen. These associations were independent of current smoking habits. Clinical atherosclerosis was associated with fibrinogen, von Willebrand factor, thrombin/antithrombin complex, plasminogen activator inhibitor activity, mean and maximum intima-media thickness and plaque status of the femoral artery. In conclusion, fibrinogen, von Willebrand factor and thrombin/antithrombin complex were related to plaque occurrence in the femoral artery. Clinical atherosclerosis was associated with fibrinogen, von Willebrand factor, thrombin/antithrombin complex and plasminogen activator inhibitor activity.
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PMID:Femoral artery wall morphology, hemostatic factors and intermittent claudication: ultrasound study in men at high and low risk for atherosclerotic disease. 869 78

Following a screening program for orally active antithrombotic drugs, it was found that a series of thioxyloside compounds presented with good venous antithrombotic properties. Of more than 500 compounds, LF 09-0055, LF 04-0212, and LF 05-0030 were the most active at inhibiting venous thrombus formation in the rat and rabbit Wessler model after intravenous and oral dosing. LF 05-0030 showed the greatest activity with an ED80 value of 6 mg/kg on oral administration in rats. This activity was maintained in several different models of venous thrombosis and shown to be devoid of anticoagulant effects or hemorrhage. Kinetic studies have demonstrated that maximal levels of activity, following either intravenous or oral dosing, occurred between 2 and 4 hours after administration. This may reflect the type of mechanism involved, since it has been well documented in the literature that xylosides are capable of initiating glycosaminoglycan (GAG) synthesis. Moreover, in vitro galactosyltransferase 1 (the second enzyme involved in GAG polymerization) enzymic assays showed that these thioxyloside derivatives were good acceptors for galactose transfer and therefore at initiating GAG formation. Further in vivo experimentation demonstrated that after treatment by these molecules an important elevation in circulating GAG occurred, with LF 05-0030 presenting the greatest activity, being five times higher than control levels. In addition it was found that dermatan sulfate levels, expressed as antithrombin activity by heparin cofactor II, were significantly increased over control values. As such, this dermatan sulfate moiety is believed to support the antithrombotic activity observed. Studies are underway to investigate the activity of these interesting molecules in atherosclerosis and other vessel wall diseases.
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PMID:Pharmacologic and biochemical profiles of new venous antithrombotic beta-D-xyloside derivatives: potential antiathero/thrombotic drugs. 883 9

The syndrome of growth hormone deficiency (GHD) in adults is associated with premature atherosclerosis, increased cardiovascular mortality, abnormal lipoprotein patterns and abnormal body composition. We have previously shown that GH-deficient adults have increased concentrations of fibrinogen and plasminogen activator inhibitor (PAI-1) activity. The aim of the present investigation was to study coagulation and fibrinolysis in 17 patients with adult-onset GHD during two years of treatment with recombinant human GH (12 micrograms/kg body weight/day). The impact of the contemporary changes in metabolic variables and body composition on coagulation and fibrinolysis was studied. The patients received conventional thyroid, adrenal and gonadal hormone replacement therapy. PAI-1 activity, PAI-1 antigen and tissue plasminogen activator (t-PA) antigen levels decreased during the GH treatment period (p < 0.05). The decrease was more pronounced in patients with high pre-treatment levels of the different variables. alpha 2-antiplasmin decreased (p < 0.05), while plasminogen was unchanged during two years of GH treatment. Fibrinogen concentrations tended to decrease after two years of GH treatment (p = 0.06), while the coagulation factors VII and VIII were unchanged. von Willebrand factor demonstrated a transient decrease after 18 months of GH treatment. The coagulation inhibitor, protein C, decreased (p < 0.05), while antithrombin was unchanged. Fasting plasma insulin increased (p < 0.01), but blood glucose did not differ after two years of GH treatment. Serum high-density lipoprotein cholesterol, total cholesterol and triglycerides were unaltered. Body fat decreased during the initial GH treatment but was unaltered after two years, while lean body mass increased (p < 0.001) and the waist over hip circumference ratio tended to decrease (p = 0.06). In conclusion, PAI-1 activity, PAI-1 antigen and t-PA antigen decreased during long-term GH treatment. These changes may be a direct effect of GH itself or may be secondary to the favourable changes in body composition. It remains to be seen whether changes in these fibrinolytic variables during rhGH treatment reduces the cardiovascular risk in patients with GHD. The present results suggest that GH plays a role in the regulation of fibrinolysis.
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PMID:Long-term treatment with growth hormone decreases plasminogen activator inhibitor-1 and tissue plasminogen activator in growth hormone-deficient adults. 888 81

There is compelling experimental evidence that tissue factor pathway inhibitor (TFPI) exerts important role(s) as a natural anticoagulant. Immunodepletion of TFPI lowers the treshold by which tissue factor (TF) can induce disseminated intravascular coagulation. Conversely, infusion of recombinant TFPI protects against thrombosis and disseminated intravascular coagulation in numerous experimental models. Since TFPI mutants associated with thrombosis have not yet been identified, a definite role of TFPI in coagulation is yet to be assigned. Current research on TFPI is mainly focused on the cell biology of TFPI, on the contribution of TFPI to the anticoagulant action of heparins, and on the role of lipoprotein-associated TFPI. TFPI is produced constitutively in endothelial cells, and is to a great extent bound to its surface. The binding molecule(s) have not yet been characterized, but TFPI is rapidly released by heparin and other negatively charged ions. In other cell lines degradation of TFPI is mediated by the low density lipoprotein receptor-related protein, which may be important for its clearance. In plasma, TFPI contributes strongly to the postheparin anticoagulant effect seen in dilute prothrombin time assays. The effect is probably mediated by redistribution of TFPI. Moreover, in the presence of heparin, antithrombin and TFPI cooperate to inhibit activation of coagulation. Antithrombin abrogates activation of factor VII bound to TF, whereas TFPI inhibits factor VIIa/TF complexes formed. The role of lipoprotein associated TFPI is still essentially unknown, but may play an important role in atherosclerosis.
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PMID:Tissue factor pathway inhibitor (TFPI)--an update. 897 19

The importance of flow in both athero- and thrombogenesis is well established. In peripheral arterial disease (PAD) atherosclerosis is disseminated, thrombosis risk high and systemic hemostatic derangement believed contributory. We studied platelet and coagulatory activity in PAD patients, thereby evaluating the clinical efficacy of Stagnation Point Flow Adhesio-Aggregometry (SPAA). SPAA provides real-time quantitative assessment of platelet adhesion and aggregation under convective, low-shear flow conditions. 62 nondiabetic PAD patients and 66 healthy volunteers were examined, whereby SPAA and conventional aggregometry were performed and circulating fibrinogen, fibrin monomer (FM), the fibrin degradation product D-Dimer and thrombin-antithrombin-complex (TAT) assessed. Conventional aggregometry detected no differences between patients and controls. SPAA-measured platelet function (p < 0.001), fibrinogen (p < 0.001), FM (p < 0.001), TAT (p < 0.02) and D-Dimer (p < 0.001) were significantly increased in patients and not effected by aspirin therapy. Respective sensitivity and specificity in detecting PAD was as follows: SPAA (96%/95%), fibrinogen (36%/92%), FM (46%/88%), TAT (40%/73%), D-Dimer (75%/80%). Increased platelet and coagulatory activity was verified in PAD, whereby flow-mediated platelet adhesion and aggregation proved the most sensitive and specific parameter. These findings indicate the usefulness of SPAA for delineating platelet-related disease mechanisms and evaluating therapeutic strategies to prevent platelet activation.
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PMID:Increased platelet and coagulatory activity in peripheral atherosclerosis flow mediated platelet function is a sensitive and specific disease indicator. 912 75

We studied the involvement of coagulation and fibrinolysis system in the induction and development of atherosclerosis in rabbits with hyperlipidemia induced by a high-cholesterol diet (HCD). In HCD rabbits, plasma lipids and atherogenic indices were maintained at a high level throughout the experimental period compared with those in rabbits fed on a standard diet. In the early phase, a significant increase in fibrinogen level was followed by increases in the activities of plasminogen and tissue-type plasminogen activator with a decrease in alpha 2-plasmin inhibitor activity and platelet count. In the middle and late phases, significant increases in plasminogen activator inhibitor-1 and antithrombin-III were observed in HCD rabbits. These results suggest that the early enhancement of coagulation followed by high activity of fibrinolysis is involved in the induction and development of hyperlipidemic thromboembolism and atherosclerosis in HCD rabbits.
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PMID:Involvement of enhanced coagulation and fibrinolysis system in induction of atherosclerosis in hyperlipidemic rabbits fed on a high cholesterol diet. 917 3

Congenital homocysteinuria is a rare inherited metabolic disorder with early onset atherosclerosis and arterial and venous trombosis. Moderate hyperhomocysteinemia is more frequently encountered and is recognized as an independent cardiovascular risk factor. Several case-control studies demonstrate an association between venous thromboembolism and moderate hyperhomocysteinemia. A patient with moderate hyperhomocysteinemia has a 2-3 relative risk of developing an episode of venous thromboembolism. The occurrence of mild hyperhomocysteinemia in heterozygotes for the mutation of Leiden factor V involves a 10-fold increase in the risk of venous thromboembolism. The biochemical mechanism by which homocysteine may promote thrombosis is not fully recognized. Homocysteine inhibits the expression of thrombomodulin, the thrombin cofactor responsible for protein C activation, and inhibits antithrombin-III binding. Treatment with folic acid reduces the plasma level of homocysteinemia, but no study has demonstrated its efficacy in reducing the incidence of venous thromboembolism or atherosclerosis. Hyperhomocysteinemia should be included in the screening of abnormalities of hemostasis and thrombosis in patients with idiopathic thromboembolism, and mild hyperhomocysteinemia may justify a trial of folic acid.
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PMID:[Homocysteine and venous thromboembolism]. 930 44

The effects of estrogen on cardiovascular risk factors have been less well defined in men than in women. We measured lipid and lipoprotein concentrations, lipoprotein particle size distributions, lipoprotein (a), homocysteine, and markers of thrombosis and fibrinolysis in 18 [corrected] healthy elderly men (age 74 +/- 3 years, mean +/- S.D.) before and after 9 weeks of treatment with 0.5, 1 or 2 mg/day of oral micronized 17beta-estradiol. LDL-C (-6%), apo B (-9%), triglyceride (-5%), and homocysteine (-11%) concentrations decreased with estradiol, whereas HDL-C (+14%) increased. Intermediate-size VLDL subclass concentrations were lowered and LDL and HDL subclass levels altered in such a way as to cause average LDL and HDL particle size to increase. Lipoprotein (a) did not change. Fibrinogen (-13%) and plasminogen activator inhibitor-1 (PAI-1) concentrations (-26%) decreased, but there were no changes in thrombotic markers including thrombin-antithrombin III complex, prothrombin fragment 1.2, D-dimer, antithrombin activity, protein-C and S and von Willebrand factor antigen. Breast tenderness occurred in four men and heartburn in five but did not require discontinuation of treatment. We conclude that oral estrogen in men reduces homocysteine, fibrinogen, and PAI-1 concentrations and favorably influences VLDL, LDL and HDL subclass levels without increasing markers of thrombotic risk.
Atherosclerosis 1998 Apr
PMID:Oral estrogen improves serum lipids, homocysteine and fibrinolysis in elderly men. 962 79

To examine the effects of atherosclerosis on the protein C anticoagulant pathway in vivo, we measured anticoagulant responses to intravenous administration of human alpha-thrombin or activated protein C (APC) in cynomolgus monkeys. Two groups of monkeys were fed either a control diet (n=18) or an atherogenic diet (n=12) that produces both hypercholesterolemia and moderate hyperhomocyst(e)inemia. A third group (n=8) was fed an atherogenic diet for 15 months, and then fed the atherogenic diet supplemented with B vitamins for 6 months to correct the hyperhomocyst(e)inemia. The plasma homocyst(e)ine level was higher in monkeys fed the atherogenic diet (9.6+/-1.0 micromol/L) than in monkeys fed the control diet (3.7+/-0.2 micromol/L) or the atherogenic diet with B vitamins (3.6+/-0.2 micromol/L) (P<0.001). Infusion of thrombin produced a much greater prolongation of the activated partial thromboplastin time in monkeys fed the control diet (52+/-10 seconds) than in monkeys fed the atherogenic diet either with (24+/-4 seconds) or without (27+/-5 seconds) supplemental B vitamins (P<0.02). Thrombin-dependent generation of circulating APC was higher in control (294+/-17 U/mL) than in atherosclerotic (240+/-14 U/mL) monkeys (P<0.05), although levels of fibrinogen, plasminogen, D-dimer, and thrombin-antithrombin complexes were similar in each group. Injection of human APC produced a similar prolongation of the activated partial thromboplastin time in control (31+/-3 seconds) and atherosclerotic (29+/-2 seconds) monkeys. These findings provide evidence for impaired anticoagulation, due partly to decreased formation of APC, in atherosclerosis. The blunted anticoagulant response to thrombin in hypercholesterolemic monkeys was not corrected by supplementation with B vitamins.
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PMID:Impaired anticoagulant response to infusion of thrombin in atherosclerotic monkeys associated with acquired defects in the protein C system. 1039 93


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