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)

Two thrombolytic agents are mainly used in patients: streptokinase (SK) and urokinase (UK). UK from human origin is an endopeptidase which is able to convert plasminogen into plasmin. UK is only secreted by the kidney and is only found in urine which is presently the only source of extraction. Studies in man have shown that UK produces a highly reproducible state of enhanced plasma thrombolytic activity with a high fibrinolysis/fibrnogenolysis ratio and a lack of toxicity and antigenicity. The half life in Animal is short as well as the duration of fibrinolytic activity in Man. In clinical experience, positive results have been reported in pulminary embolism while the issues in myocardial infarction are controversial. Suggestive results have been registered in deep vein thrombosis, in ophthalmologic field and in desobstruction of arterio-venious shunts. No evident benefit has been noted in cerebral vascular disease. Up to now, UK has been very well tolerated.
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PMID:[Urokinase. Biochemical therapeutical and therapeutical data (author's transl)]. 6 58

The defibrinating agent ancrod has had limited clinical trial, but appears to give no advantages over heparin. Intravenous infusion of dextran, a glucose polymer, has been shown to have an antithrombotic effect in many experimental models of thrombosis. However, the evidence that dextran is a clinically valuable antithrombotic drug is conflicting. A number of controlled randomized studies have shown that dextran can prevent postoperative venous thromboembolism when a large volume of dextran 40 or 70 was infused rapidly during and after surgery. However, blood volume expansion during dextran treatment prohibits its use in patients with reduced cardiac reserve, and infrequent though sometimes severe, allergic reactions have been reported. Evidence that dextran is of value for the treatment of venous or arterial thromboembolism comes from uncontrolled studies and is not convincing. Many compounds have been shown to inhibit platelet function in vitro but only five of these drugs have been extensively evaluated as prophylactic or therapeutic antithrombotic agents in man. These are aspirin, sulphinpyrazone, dipyridamole, hydroxychloroquine and clofibrate. They have been evaluated mainly in patients with cerebral vascular disorders, coronary artery disease, peripheral artery ischaemia, venous thromboembolism, prosthetic heart valves, and in patients with arteriovenous shunts. The evaluation of the clinical effect of the platelet function suppressing drugs is in its early stages, but they appear to differ from each other in the spectrum of their clinical effectiveness, and they may be more effective in arterial than in venous thromboembolic disorders. Their role in the management of cerebral vascular disease and coronary artery disease is still uncertain, and should be clarified by the results of a number of multi-centre, prospective, randomized studies which are currently in progress. Three types of thrombolytic drugs have been evaluated clinically; the plasminogen activators streptokinase and urokinase, proteolytic enzymes such as plasmin, and agents which increase the level of endogenous plasminogen activator (e.g. anabolic steroids). Of these, the plasminogen activators now have a definite place in clinical practice. The plasminogen activators accelerate the lysis of recent venous thrombi and pulmonary emboli, and of arterial thrombi or emboli. Thrombolytic therapy with these agents should be considered particularly in patients with recent major pulmonary embolism, as lysis of recent emboli is rapid and substantial. It should also be considered in patients with recent extensive venous thrombosis, because total lysis of venous thrombi has been reported to result in long-term preservation of valve function, and is likely to prevent postphlebitic syndrome, though this has not been proven. However, plasminogen activator therapy carries a higher risk of bleeding than heparin treatment...
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PMID:Antithrombotic drugs: part II. 78 6

Balloon angioplasty and bypass graft surgery are common procedures for treating vascular occlusive disease. The purpose of this preliminary investigation was to evaluate the effectiveness and the safety of a new catheter system, first introduced by KR Kensey. The system involves a flexible catheter with a high speed rotating tip, driven by an electrical motor. The tip is cooled by a continuous flow of sterile saline containing dextran 40, heparin and urokinase. Radiopaque contrast medium may be infused through the catheter to allow the device to be guided and to detect lesions and to evaluate the efficacy of treatment. The system was applied in three patients with occlusive vascular disease (Stage IIb) and segmental or total occlusion of the superficial femoral artery (SFA). The milling catheter was introduced percutaneously into the common femoral artery and guided to the area of occlusion under DSA control. In two patients total recanalisation was achieved after passage of the milling catheter. In one patient the totally occluded SFA could not be cannulated and a femoro-popliteal bypass was performed one week later. Complications such as perforation of the vessel or peripheral embolisation were not observed. Pedal pulses were improved significantly in one patient. Further investigations will be necessary to demonstrate whether the milling catheter can be safely used to revascularise patients with limb threatening peripheral vascular disease.
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PMID:Dynamic angioplasty--a milling catheter for transcutaneous and intraoperative treatment of vascular occlusive disease. 297 85

In the past 20 years treatment appears to have had a major impact on all forms of cerebral vascular disease. Morbidity and mortality from strokes have declined nearly 50% in developed countries. Modern imaging techniques, methodology, and biostatistics have identified risk factors and refined clinical trials such that we question all previous studies of stroke management. Control of moderate and severe hypertension has significantly lowered stroke rates. In borderline and mild hypertension the decision to treat is influenced by other stroke risk factors including diabetes mellitus, cigarette smoking, ischaemic heart disease, plasma lipid levels, gout, haematocrit, and body weight. Current data indicate that anticoagulants are of no value, or hazardous, in atherothrombotic strokes; of unknown value in transient ischaemic attacks; of dubious value in evolving strokes; and beneficial in cardiac embolism. The cardiac causes, including mural thrombus, unstable arrhythmias, and mitral valve prolapse should be actively sought. Aspirin, as the prototype anti-platelet agent, holds promise in transient ischemic attacks and minor strokes at both small and moderate dosages. Ticlopine is now being critically evaluated in America. Use of cerebral vasodilators should be abandoned. Enthusiasm in the use of streptokinase and urokinase has been dampened by the conversion of ischemic infarcts into haemorrhagic infarcts. In subarachnoid haemorrhage epsilon-aminocaprioc acid is useful although hazardous, in preventing rebleeding. Certain calcium ion channel blockers are promising in the reduction of vasopasm. Since the November 1985 article in the new England Journal of Medicine on the failure of external-to-internal carotid arterial bypass to reduce the risk of ischemic stroke, the swing is back to conservative management.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Advances in the medical management of cerebral vascular disease. 331 47

In summary, studies of the expression of fibrinolytic genes in the vessel wall suggest an active, ongoing proteolytic process, the activity of which is dependent on the relative amounts of tPA, uPA, and PAI-1 secreted and locally deposited. Disturbances in the balance of pro- and antifibrinolytic activity in atherosclerotic vessels have considerable potential for influencing both intra- and extravascular fibrinolytic events and may be causally related to the development of vascular disease.
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PMID:Abnormalities in the fibrinolytic system of the vascular wall associated with atherosclerosis. 753 27

The effect of a 17-kringle form of recombinant apo(a) [r-apo(a)] on in vitro fibrin clot lysis was studied. In these assays, fibrin clots were formed in the wells of microtiter plates, and lysis of the clots was monitored by measurement of the turbidity at 405 nm. The results indicate that r-apo(a) produces a dose-dependent antifibrinolytic effect in clots formed using either purified components or barium-adsorbed plasma. This effect was found to be independent of clot structure, since lysis of clots formed using both high and low concentrations of thrombin was prolonged by r-apo(a) to the same extent. The two components of the antifibrinolytic effect of r-apo(a) were determined to be (i) attenuation of tPA-mediated plasminogen activation (the major component) and (ii) inhibition of plasmin degradation of fibrin, although r-apo(a) did not directly attenuate plasmin activity, as measured by S-2251 hydrolysis. r-Apo(a) interfered most substantially with tPA-mediated activation of Glu-plasminogen and less substantially with tPA-mediated Lys-plasminogen activation and urokinase-mediated activation of plasminogen. In summary, we have demonstrated that apo(a) is able to attenuate fibrin clot lysis in vitro, primarily as a consequence of the interference by apo(a) with tPA-mediated Glu-plasminogen activation. These studies illuminate possible mechanisms by which Lp(a) may contribute to the development of vascular disease in vivo.
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PMID:Antifibrinolytic effect of recombinant apolipoprotein(a) in vitro is primarily due to attenuation of tPA-mediated Glu-plasminogen activation. 771 Oct 34

Blackfoot disease is a unique endemic and chronic progressive arteriosclerotic vascular disease in southwest area of Taiwan. In this study, we determined the plasma levels of tissue plasminogen activator (tPA), plasminogen activator inhibitor (PAI), urokinase plasminogen activator (uPA), and von Willebrand factor (vWF) antigen in Blackfoot disease patients, in comparison with normal controls from non-endemic areas and the endemic area, Putai. Blackfoot disease patients had mean tPA antigen level of 7.9 ng/ml (n = 27) which was significantly lower (p < 0.05) than both the normal controls with 11.0 ng/ml (n = 20) and the Putai normal controls with 9.7 ng/ml (n = 39). However, the mean PAI-1 antigen level in the patient group was 41.2 ng/ml (n = 28) which was significantly higher (p = 0.0001) than both the normal controls with 19.7 ng/ml (n = 23) and the Putai normal controls with 21.3 ng/ml (n = 40). Furthermore, in the patient group, a significantly lower (p < 0.005) mean uPA antigen level (2.3 ng/ml, n = 18) was noted as compared with that in the normal controls (3.2 ng/ml, n = 14). No significant difference was observed in vWF antigen level between patients and normal controls. This study suggests that a reduced capacity for fibrinolysis is associated with Blackfoot disease.
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PMID:Impaired fibrinolysis in patients with Blackfoot disease. 830 60

Neovascularization of the atherosclerotic plaque is responsible for its weakening and consequently for the complications of vascular disease. Macrophages are a source of growth factors that can modulate angiogenesis. In this study, we analyzed the effect of oncostatin M (OSM) on angiogenesis, as it could be involved in the development of atherosclerosis. The effect of OSM was compared with those of leukemia inhibitory factor (LIF) and interleukin-6 (IL-6). On human dermal microvasculature endothelial cells (HMEC-1s), OSM (22.5 to 112.5 pmol/L) induced a dose-dependent increase in cell proliferation greater than that induced by the classic angiogenic factors vascular endothelial growth factor (VEGF; 543 pmol/L) and basic fibroblast growth factor (bFGF; 1.1 nmol/L). LIF (19 to 475 pmol/L) induced only a 30% increase in cell proliferation, and IL-6 had no effect. Furthermore, in a modified Boyden-chamber model, OSM, LIF, and IL-6 were chemoattractant for HMEC-1s. In a tridimensional gel of fibrin, OSM increased tube formation and tube length, which were already noticeable by day 3. LIF and IL-6 induced a weaker effect that was only obvious by day 10. The angiogenic effect of OSM was also demonstrated in vivo in a rabbit corneal model: OSM was more potent than LIF, the length of the neovessels being longer with OSM than with LIF, whereas IL-6 was without effect. We tested factors that could be involved in the proliferative effect of OSM on HMEC-1s. OSM induced only a slight increase in the urokinase receptor and a 60% increase in VEGF secretion, whereas it does not modify IL-8 secretion or bFGF levels. The effect of OSM seems to depend on endothelial cell origin and cell species: OSM (up to 112.5 pmol/L) did not induce human umbilical vein endothelial cell proliferation and even had a small inhibitory effect (17%) on calf pulmonary artery endothelial cells. In conclusion, OSM induces an angiogenic effect on capillary endothelial cells, which could be, at least in part, implicated in pathological processes such as atherosclerosis or tumor growth.
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PMID:Oncostatin M induces angiogenesis in vitro and in vivo. 1044 61

Overexpression of urokinase plasminogen activator (uPA) in endothelial cells can decrease intravascular thrombosis. However, expression of uPA is increased in atherosclerotic human arteries, which suggests that uPA might accelerate atherogenesis. To investigate whether elevated uPA expression accelerates atherogenesis, we cloned a rabbit uPA cDNA and expressed it in carotid arteries of cholesterol-fed rabbits. uPA gene transfer increased artery-wall uPA activity for at least 1 week, with a return to baseline by 2 weeks. One week after gene transfer, uPA-transduced arteries were constricted, with significantly smaller lumens and thicker walls, but no difference in intimal or medial mass. Two weeks after gene transfer, uPA- and control-transduced arteries were morphologically indistinguishable. By 4 weeks, however, uPA-transduced arteries had 70% larger intimas than control-transduced arteries (P < 0.01) and smaller lumens (P < 0.05). Intimal lesions appeared to be of similar composition in uPA- and control-transduced arteries, except that degradation of elastic laminae was evident in uPA-transduced arteries. These data suggest that elevated uPA expression in atherosclerotic arteries contributes to intimal growth and constrictive remodeling leading to lumen loss. Antagonists of uPA activity might, therefore, be useful in limiting intimal growth and preventing constrictive remodeling. Overexpression of uPA in endothelial cells to prevent intravascular thrombosis must be reconsidered, because this intervention could worsen underlying vascular disease.
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PMID:Increased expression of urokinase during atherosclerotic lesion development causes arterial constriction and lumen loss, and accelerates lesion growth. 1214 63

The accumulation of fibrillar amyloid-beta protein (A beta) in cerebral blood vessels, a condition known as cerebral amyloid angiopathy (CAA), is a key pathological feature of Alzheimer's disease and certain related disorders and is intimately associated with cerebrovascular cell death both in vivo and in vitro. Moreover, severe CAA leads to loss of vessel wall integrity and cerebral hemorrhage. Although the basis for these latter pathological consequences in CAA remains unresolved alterations in local proteolytic mechanisms may be involved. Here we show that pathogenic forms of A beta stimulate the expression of plasminogen activator activity in cultured human cerebrovascular smooth muscle (HCSM) cells, an in vitro model of CAA. RNase protection assays and plasminogen zymography showed that urokinase-type plasminogen activator (uPA) was responsible for this activity. There was preferential accumulation of uPA on the HCSM cell surface that was mediated through a concomitant increase in expression of the uPA receptor. In the presence of plasminogen there was robust degradation of A beta that was added to the HCSM cells resulting in restoration of cell viability. This suggests that increased expression of uPA may initially serve as a protective mechanism leading to localized degradation and clearance of the pathogenic stimulus A beta. On the other hand, chronic expression of uPA and plasminogen activation led to a profound loss of HCSM cell attachment. This suggests that a similar prolonged effect in vivo in the cerebral vessel wall may contribute to loss of integrity and cerebral hemorrhage in CAA.
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PMID:Amyloid beta-protein stimulates the expression of urokinase-type plasminogen activator (uPA) and its receptor (uPAR) in human cerebrovascular smooth muscle cells. 1275 71


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