Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042373 (vascular disease)
 17,070 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Epidemiological studies have consistently correlated plasma fibrinogen level to the risk of coronary heart disease (CHD) and acute ischemic stroke. Several mechanisms have been proposed such as the role of fibrinogen in the viscosity of blood, the participation of fibrinogen in both fibrin clot formation and platelet aggregation. However, there is no evidence that the increase in fibrinogen is directly responsible for the vascular disease since the cytokines which participate to the synthesis of fibrinogen by the hepatocytes, such as interleukin 6, could also induce an endothelial cell damage by increasing tumor necrotic factor (TNF) production. In these conditions fibrinogen increase could therefore only represent a marker of cytokine production which in turn is responsible for vascular injury. In addition, for the pathogenesis of atherosclerosis, the influence of fibrinogen is not only mediated by way of increased fibrinogen concentration but could be due to a structurally variant fibrinogen. The recent epidemiological studies have shown that the variation at the beta locus of fibrinogen is associated with an increase risk of peripheral atherosclerosis. The finding concerning dysfibrinogenemia and thrombosis (Dusart and Tampere) create further opportunities to enrich knowledge of the link between the association of abnormal gel structure and thrombotic diseases such as myocardial infarction or stroke at young age. This abnormal clot structure could contribute to thrombogenicity by decreasing the capacity of these clots to be degraded by fibrinolytic enzymes or by decreasing thrombin binding since fibrin is considered as a "thrombin trap".(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Fibrinogen, a vascular risk factor]. 819 48

Immunohistochemical studies of human atherosclerotic lesions have demonstrated the occurrence of fibrin deposition and its degradation in the arterial wall. We studied fibrinogen, the generation of thrombin, and the degradation of fibrin in 40 patients with stable peripheral arterial occlusive disease of varying severity, as assessed by the ankle/brachial pressure index and duplex ultrasonography and/or angiography. Circulating fibrinogen (functional and immunological), fibrinopeptide A, thrombin-antithrombin III complex, and D-dimer were measured. The severity of atherosclerosis was associated with both fibrinogen (both functional and immunological) and D-dimer (r = .57, P < .0002, and r = .57, P < .0001, respectively). Fibrinogen and D-dimer showed a significant positive correlation (r = .50, P < .001). Generation of thrombin was detected in 24 patients (60%) by fibrinopeptide A and levels of thrombin-antithrombin III complex. As a sign of coagulation activation and fibrinolysis, we found that thrombin-antithrombin III complex and the degradation of cross-linked fibrin were progressively associated with the extent of vascular disease. The plasmin-mediated fibrin breakdown contributed to increased levels of circulating fibrinogen, an established risk factor for thrombotic complications. The significant correlations between fibrinogen/D-dimer and the severity of atherosclerosis support previous pathological studies and imply that local degradation of cross-linked fibrin is involved in the progression of atherosclerosis.
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PMID:Severity of peripheral atherosclerosis is associated with fibrinogen and degradation of cross-linked fibrin. 824 Oct 93

The effect of exercise on plasma coagulant activity was studied in 16 subjects with newly-diagnosed type II diabetes without vascular complications and 9 healthy volunteers. Generation of thrombin was determined by a computer-assisted chromogenic method and results expressed as time to generate 50% maximal thrombin activity (T50/s). In addition, APTT, factor VIII and thrombin-antithrombin III (TAT) complex levels were measured. Pre-exercise FVIII:C [mean (+/- SD)] was increased in diabetic compared to control subjects [1.5 (0.4); 0.9 (0.2) IU ml-1; (p < 0.001) respectively]. No significant differences in APTT, TAT or T50 were detected between the groups. Exercise induced a rise in FVIII complex, reduction of APTT [33 (2) s to 31 (2) s; (p = 0.004)] and T50 [58 (6) s to 53 (6) s; (p = 0.01)] in controls and an increase in FVIII complex but no significant changes in APTT or T50 in diabetic patients, with no change in TAT in either group. A greater increase in FVIII:C than vWF levels occurred in controls [0.2 (0.1); 0.1 (0.1) IU ml-1; (p = 0.005)] and patients [0.3 (0.4); 0.2 (0.1) IU ml-1; (p = 0.032)]. In patients, FVIII:C correlated inversely with APTT (r = -0.522, p = 0.038) and T50 (r = -0.592, p = 0.016). The results show that FVIII:C levels are increased at diagnosis in patients with type II diabetes without vascular disease but there is no enhancement of plasma procoagulant activity. In healthy individuals, exercise induced activation of coagulation which was not seen in patients, suggesting that it does not precipitate a state of accelerated thrombogenesis in subjects with uncomplicated type II diabetes.
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PMID:The effect of short-term exercise on plasma procoagulant activity in patients with type II (non-insulin-dependent) diabetes and healthy volunteers. 836 78

Local accumulation of plasminogen activator inhibitor-1 (PAI-1) in response to thrombosis has been implicated not only in inhibition of fibrinolysis but also in the pathogenesis of vascular disease. To determine whether thrombin, known to be released from thrombi, can induce expression of PAI-1 in vascular smooth muscle, bovine aortic smooth muscle cells were exposed to highly purified bovine thrombin. Thrombin, in the absence of serum, induced production of PAI-1 by bovine aortic smooth muscle cells in a dose-dependent manner. PAI-1 activity in the conditioned media reached a maximum with 12 nM thrombin. Metabolic labeling with [35S]methionine demonstrated that the elaborated PAI-1 was newly synthesized and that it comprised both a cleaved inactive 42-kd form and an uncleaved active 46-kd form. The increase of PAI-1 activity in the media paralleled the thrombin-induced increase in the concentration of the 46-kd form. Preincubation of thrombin with hirudin, a specific inhibitor of thrombin, or with D-phenylalanyl-L-prolyl-L-arginine chloromethyl ketone, an inhibitor of the active site of thrombin, prevented the induction of PAI-1 synthesis. The stimulatory effect of thrombin on PAI-1 synthesis was also evident at the level of expression of mRNA, with steady-state PAI-1 mRNA levels increasing by 100% in 4-8 hours. When the bovine aortic smooth muscle cells were exposed to transforming growth factor-beta 1, an agonist shown previously to increase PAI-1 synthesis in diverse cell types, synergy with thrombin was evident.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Induction of vascular smooth muscle cell expression of plasminogen activator inhibitor-1 by thrombin. 841 45

Biopsy specimens from 80 cardiac allografts were studied immunocytochemically with nine antibodies selected to identify cellular, immunologic, and vascular aspects of rejection. Results from these experiments were converted to a numeric base and used to calculate rejection indexes for each of these aspects of rejection. Pretransplantation biopsy specimens of donor hearts were studied to determine normal values, and clinical, catheterization, and conventional biopsy findings were used to classify patients as stable or unstable. The standard deviation of cellular and immunologic reaction indexes were overlapping for stable and unstable patients, but the vascular indexes for these patient groups were significantly different, suggesting that vascular damage defines clinical instability in cardiac allograft recipients. To study the vascular index in the absence of cellular infiltrates, biopsy specimens from 80 allografted hearts were selected to represent 40 patients with cellular infiltrates and 40 patients devoid of infiltrates. The results of this analysis revealed no difference in the vascular index between hearts that contained or did not contain infiltrates; the spectrum of vascular damage between the groups ranged from trivial to severe, suggesting that vascular damage was not dependent on cellular infiltrates. Concluding that these were independent events was not possible, however, because none of the hearts continuously were devoid of cellular infiltrates. Two groups of patients with significantly different vascular indexes then were studied for a systemic manifestation of coagulation by measurement of their thrombin times. The group with low vascular index was found to have significantly prolonged thrombin times compared to the group with high vascular index, and a trend to less prolongation of thrombin times was observed in another group with high cellular index. The relation of these results with cardiac allograft vasculopathy is not established, but the results suggest hitherto unexplored roles for quantitative expressions of hemostasis, fibrinolysis, and anticoagulation in the pathophysiology of vascular disease in allografts.
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PMID:Vascular lesions in biopsy specimens devoid of cellular infiltrates: qualitative and quantitative immunocytochemical studies of human cardiac allografts. 847 94

Diabetes mellitus is associated with disturbances in hemostasis that could contribute to the development of diabetic vascular disease. We investigated the changes in parameters of blood coagulation and the fibrinolytic system and in plasma levels of lipoprotein(a)(Lp(a)) in 124 patients with type II diabetes mellitus and 44 healthy control subjects matched for age and body mass index (BMI) to determine whether hemostatic disturbances may lead to increased cardiovascular mortality. Median levels of fibrinogen (P < 0.0001), thrombin-antithrombin III complex (TAT) (P < 0.005), and plasminogen activator inhibitor-1 (PAI-1) activity (P < 0.05) in plasma were significantly elevated in diabetic patients compared with controls. The median concentration of Lp(a) was significantly higher in diabetic patients than in normal controls (18.2 vs. 12.6 mg/dl. P < 0.0005). Lp(a) levels tended to be elevated in patients with a prolonged history of diabetes. There was no evidence that Lp(a) levels were affected by metabolic control or by type of treatment. Twenty-two diabetics with coronary heart disease (CHD) had significantly higher levels of fibrinogen (P < 0.05), TAT (P < 0.05), and Lp(a) (24.7 vs. 13.7 mg/dl, P < 0.01) than the 51 patients without diabetic angiopathy. Our data indicate that impaired hemostatic balance in diabetes may cause hypercoagulability and may thus contribute to the increased cardiovascular mortality in diabetes.
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PMID:Hypercoagulability and high lipoprotein(a) levels in patients with type II diabetes mellitus. 864 73

Determination of various important parameters of coagulation and fibrinolysis, clinical characteristics, and levels of serum lipid were compared in 193 patients with NIDDM and 50 control subjects. Levels of fibrinogen, tissue factor pathway inhibitor (TFPI), thrombin-anti-thrombin complex, and plasminogen activator inhibitor 1 in plasma increased significantly in the diabetic patients. Levels of TFPI correlated significantly with levels of total cholesterol. In the patients with coronary heart disease or cerebral infarction, levels of lipoprotein(a) increased significantly. From these results, we have concluded that there is a thrombotic tendency or at least an imbalance between the hemostatic and thrombosis-protecting system in diabetic patients, especially in patients with angiopathy.
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PMID:Mechanism on disorders of coagulation and fibrinolysis in diabetes. 867 73

The aim of the present study was to evaluate some metabolic, coagulation and fibrinolytic parameters in 35 patients (24 males and 11 females, mean age 57 +/- 4 years) suffering from myocardial infarction more than 6 months before with or without carotid atherosclerotic lesions. After evaluation by B-mode duplex scanning system of extracranial carotid arteries, the patients were subdivided into two groups: Group 1 (n = 16, with carotid plaques or intima-media thickening) and Group 2 (n = 19, without carotid plaques or intima-media thickening). Eighteen age- and sex-matched subjects were recruited as controls (Group 3). Groups 1 and 2 displayed significantly higher levels of total cholesterol and apolipoprotein B and significantly lower levels of HDL-cholesterol and apolipoprotein A1 than Group 3, while serum triglyceride and lipoprotein (a)-Lp (a) levels were significantly higher in Group 1 as compared to the control group. Moreover, Group 1 and 2 displayed significantly higher levels of factor VII, fibrinogen, F1+2, thrombin-antithrombin complex and plasminogen activator inhibitor (PAI) post venous occlusion and significantly lower levels of tissue plasminogen activator (t-PA) post venous occlusion than Group 3. Significantly higher levels of t-PA and PAI pre venous occlusion and significantly lower levels of antithrombin III, C-protein and S-protein were observed in Group 1 as compared to controls. In patients with highest Lp(a) level, the lowest t-PA level post venous occlusion and the highest PAI level post venous occlusion were observed. Our data show an activation of coagulation and a deficient fibrinolysis in survivors of myocardial infarction, particularly in those with associated carotid atherosclerotic lesions. We speculate that this thrombophilic state may play a key role in the pathogenesis of atherosclerotic vascular disease and thromboembolic complications.
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PMID:[Thrombophilic state inpatients suffering from myocardial infarction with or without carotid atherosclerotic lesions]. 870 61

Vessel wall damage and changes in hemostatic mechanisms are important factors in thrombogenesis. Vascular damage may be encountered in trauma, inflammatory processes, and other forms of vascular disease. Systemic changes in platelets and in certain coagulation constituents also contribute to thrombus formation. The generation of thrombin seems to be a pivotal event in thrombogenesis, and inactivation of this enzyme has been attempted for many years with heparin, low-molecular-weight heparin, and other glycosaminoglycans. Different forms of heparin may act differently, and the future must more clearly elucidate the role of the endothelium in all of these processes.
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PMID:Pathophysiology of thromboembolism and its modulation by low-molecular-weight heparins. 880 25

High plasma fibrinogen levels are associated with vascular complications in the general population. Fibrin, the structural element in a clot, is derived from fibrinogen by activation of thrombin. An abnormal fibrin gel structure has been demonstrated in patients with myocardial infarction and in diabetic patients during poor metabolic control. In the present study the properties of fibrin gel structure were investigated in 20 patients with insulin-dependent diabetes mellitus (IDDM): 10 patients without (age: 30 +/- 8; diabetes duration: 7 +/- 6 years), and 10 patients (age: 44 +/- 7; diabetes duration: 27 +/- 9 years) with microangiopathy. Fifteen healthy subjects served as controls (age: 40 +/- 8 years). The glycosylated haemoglobin level (HbA1c) was elevated (p < 0.001) in the patients: 6.5 +/- 1.5% in diabetic patients without, and 7.1 +/- 1.0% in diabetic patients with microangiopathy. C-reactive protein and plasma fibrinogen were similar as compared to healthy control subjects. The properties of the fibrin gel structure; i.e. the permeability coefficient (Ks) and the fibre mass length ratio (mu) formed in recalcified plasma on addition of thrombin were investigated. Ks was decreased in the diabetic patients, with (6.5 +/- 2.0 cm2; p < 0.01) and without microangiopathy (6.5 +/- 2.7 cm2; p < 0.05), as compared to healthy subjects (10.0 +/- 3.4 cm2), while mu was not significantly (p = 0.14) altered. The results indicate a lower fibrin gel porosity in patients with IDDM, despite normal plasma fibrinogen and irrespective of microangiopathy. The abnormal fibrin gel structure may be due to an increased glycosylation of the fibrin (-ogen) molecule caused by long-term hyperglycaemia and may be of importance for the development of angiopathy in diabetic patients.
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PMID:Altered properties of the fibrin gel structure in patients with IDDM. 924 13


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