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

Traditionally, plasmin generation has been conceptualized as a process oriented on the surface of a fibrin-containing thrombus. Recent work, however, indicated that plasminogen and its activators, tissue plasminogen activator (t-PA) and urokinase, can assemble on the surface of cultured human umbilical vein endothelial cells (HUVECs). On binding to HUVECs, plasminogen is activated by t-PA approximately 12-fold more efficiently than fluid-phase plasminogen, and is converted to a plasmin-modified form, possibly unique to cell surfaces. In addition, t-PA interacts with HUVECs at two sites. The major binding site preserves its activity and represents a true (relative molecular weight 40,000) membrane-associated exoreceptor. The low-density lipoprotein (LDL)-like lipoprotein, lipoprotein(a), is highly associated with atherosclerosis, bears striking sequence homology to plasminogen, and competes with plasminogen for cell surface binding. In summary, functional assembly of plasminogen and t-PA may represent an important thromboregulatory system.
 ...
PMID:Assembly of plasmin-generating proteins on the surface of human endothelial cells. 134 92

A 38 year old woman with systemic lupus erythematosus (SLE) was admitted because of epigastralgia and fever. The diagnosis of SLE was made 22 years ago based on Raynaud's phenomenon, butterfly rash, hair loss, photosensitivity and positive antinuclear antibody. She had episodes of consciousness disturbance, transient visual disturbance of the left eye, and a necrosis of the left big toe. She underwent artificial arthroplasty of bilateral femoral heads 11 years ago, when multiple aseptic necroses of thirteen bones were found, and when anti-cardiolipin (CL) antibody was found to be positive. An echogram of abdomen suggested an obstruction of superior mesenteric artery (SMA) when she was admitted. Selective angiography revealed a complete obstruction of SMA and splenic artery, and incomplete obstruction of celiac artery. Conservative treatment with urokinase infusion and prednisolone 50 mg/day was not effective, and small intestine and right colon were resected on the 23rd hospital day. The pathological examination showed thrombosis of SMA. There was no evidence of arteritis or atherosclerosis. Anti-CL antibody and lupus anticoagulant were positive on admission, but the level of both anti-DNA antibody and complement was normal. Therefore, it was suggested that the thrombosis was related with anti-phospholipid antibody. The characteristic clinical feature were multiple aseptic bone necroses and thromboses of several arteries. We discussed the relationship of thrombosis and the etiology of multiple bone necrosis in this case with anti-phospholipid antibody.
 ...
PMID:[A systemic lupus erythematosus patient with multiple aseptic bone necroses, thrombosis of superior mesenteric artery and anti-phospholipid antibody]. 144 87

Emergency coronary angiography in a 28-year-old male suffering an acute anteroseptal myocardial infarction revealed complete obstruction of the left anterior descending artery in association with multiple aneurysms of the 3 major coronary arteries. Successful intracoronary thrombolytic treatment with urokinase infusion directly into the infarct-related artery was performed 2 h after the onset. Follow-up left ventriculogram showed preservation of left ventricular wall motion. Fifty days after the infarction, he underwent aorto-coronary bypass surgery. Histological examination of the biopsy specimen obtained from the aneurysm of the distal portion of the right coronary artery revealed that the 3-layer architecture of the arterial wall had been completely lost. The wall was replaced by fibrotic tissue, with slight mononuclear cell infiltration around the small vessels, but no acute inflammatory reaction or atheromatous change was seen. In spite of the presence of the coronary risk factors of hypertension and hyperlipidemia, angiography revealed no evidence of atherosclerosis of systemic arteries. It is suggested that the coronary aneurysms in this case are possible sequelae of Kawasaki disease in childhood.
 ...
PMID:Acute myocardial infarction in a young adult as possible sequela of Kawasaki disease--a case report of successful intracoronary thrombolytic therapy and histological study of an aneurysm. 149 60

A 63-year-old man was admitted with an acute anteroseptal myocardial infarction. Coronary angiography performed 3 hours after the onset of chest pain revealed 99% stenosis of the proximal left anterior descending coronary artery (LAD) with delayed filling and intraluminal thrombus distal to the stenosis. After the intracoronary injection of isosorbide dinitrate, the delayed filling disappeared and a subsequent intracoronary urokinase partially dissolved the thrombus. Repeat coronary angiography in the chronic phase disclosed 75% stenosis of the LAD and disappearance of the thrombus. Intracoronary acetylcholine provoked a coronary spasm at the stenotic site of the LAD, concomitantly with chest pain and ST-segment elevation in the anterior leads. The present case demonstrated that coronary spasm plays an important role in thrombus formation and acute myocardial infarction. To date, the concept has been postulated that a dynamic interaction between atherosclerosis, platelet aggregation and spasm may work to cause coronary thrombosis and subsequently lead to acute myocardial infarction. Our report shed light on the importance of coronary spasm in the pathogenesis of myocardial infarction.
 ...
PMID:[Coronary spasm-induced acute myocardial infarction associated with intracoronary thrombosis]. 156 86

The plasma concentration of lipoprotein (a) [Lp(a)] is correlated with the risk of atherosclerosis. It is a lipoprotein particle consisting of apoprotein (a) [Lp(a)] is correlated with the risk of atherosclerosis. It is a lipoprotein particle consisting of apoprotein (a) [apo(a)], a protein showing considerable amino acid sequence identity with plasminogen. bound to low-density lipoprotein. The apo(a) portion of Lp(a) was recently shown to have serine-proteinase-type amidolytic activity and to be able to degrade the adhesive glycoprotein fibronectin. To characterize this enzyme activity further, we used chromogenic peptide substrates and inhibitors. Of the substrates tested, those with arginine at the scissile bond [N-alpha-benzoyl-L-Arg p-nitroanilide (pNA), N-alpha-benzoyl-Ile-Glu-Gly-Arg-pNA, N-alpha-benzyloxycarbonyl-Arg-Gly-Arg-pNA] gave the highest hydrolysis rates. Synthetic substrates with plasmin specificity (Val-Leu-L-Lys-pNA and Val-Phe-L-Lys-pNA) were not hydrolysed by Lp(a). Neither tissue plasminogen activator nor urokinase had any effect on the enzyme activity. The addition of antibodies to these plasminogen activators did not inhibit the enzyme activity of Lp(a). Inhibition experiments with phenylmethanesulphonyl fluoride, carbodi-imide, dichloroisocoumarin and competitive peptide inhibitors demonstrated that Lp(a) has enzyme activity that closely resembles that of serine proteinases. Whether this serine-proteinase activity of Lp(a) plays any role in the genesis of atherosclerosis remains to be established.
 ...
PMID:Characterization of the enzyme activity of human plasma lipoprotein (a) using synthetic peptide substrates. 182 80

A 14-year old girl taking oral contraceptives (OCs) for menstrual disorders was admitted with an acute anterior myocardial infarction and underwent immediate coronary arteriography and intracoronary thrombolysis (urokinase 350,000 units) within 4 hours of the onset of symptoms. A segmental occlusion of the left anterior descending artery with no evidence of coronary atherosclerosis elsewhere was shown. A successful recanalization was documented after fibrinolytic therapy. The present is the 1st reported case in a patient of this age, with an angiographic demonstration during the acute phase of the tromboembolic pathogenesis of myocardial infarction in contraceptive users. The potential benefit of early thrombolytic treatment in this rare clinical setting is thus suggested. (author's)
 ...
PMID:[Acute myocardial infarct in a 14-year-old girl treated with contraceptives. Coronary arteriography and immediate thrombolytic therapy]. 276 75

Lp(a) represents a genetically transmitted class of plasma LDL having apo B-100 linked by a disulfide bridge to a glycoprotein, apo(a). Lp(a) is heterogeneous in size and density. Apo(a) is also heterogeneous in size (molecular weight between approximately 300,000 and 700,000) due probably to the polymorphism of both polypeptide and carbohydrate chains. Recent studies have shown that apo(a) has a striking amino acid sequence homology with plasminogen, a serine protease zymogen that following activation to plasmin enters the fibrinolytic system. Apo(a) is severalfold larger than plasminogen (molecular weight approximately 90,000) and also differs from it because it fails to be activated to plasmin. This is due to the fact that arginine is replaced by serine at the site of cleavage by streptokinase, urokinase, or tissue plasminogen activator. A single gene locus appears to control the Lp(a) polymorphism as well as the concentration of the Lp(a) phenotypes in the plasma. Patients with high plasma levels of Lp(a) have been shown to have an increased incidence of cardiovascular disease but a causal relationship has not been firmly established. The information that is being rapidly acquired on the structure of Lp(a) should facilitate the understanding of the molecular basis of the polymorphism of this genetic variant and of the role that the various Lp(a) phenotypes play in atherosclerosis and thrombosis. The potential physiologic role of Lp(a) remains open to inquiry.
 ...
PMID:Lipoprotein(a): a genetically determined lipoprotein containing a glycoprotein of the plasminogen family. 297 66

Plasminogen Activator Inhibitors (PA Inhibitor) have recently been identified in plasma. They are directed against t-PA and Urokinase. Two PA Inhibitors have been described: PA Inhibitor 1 from endothelial cells, hepatocytes and platelets and PA Inhibitor 2 from placenta. Enzymatic assays have been developed. They show that plasma levels of PA Inhibitor are very low under normal conditions, but a considerable increase (X10 or 20) is found in several pathological conditions (thrombo embolic disease, atherosclerosis, thrombotic risk factors (obesity, hypertriglyceridemia, diabetes) inflammatory syndrome, post operative period for PA Inhibitor 1, and in some physiological conditions (pregnancy for PA Inhibitor 2). These results plead for a pathogenic role of PA Inhibitor 1 in the development of thrombosis. Pharmacological products able to decrease the plasma level of PA Inhibitor are as yet scarce. Stanozolol, an anabolic steroid, some biguanides such as Metformin possess this property.
 ...
PMID:[Anti-activator inhibitors of plasminogen]. 311 99

Apolipoprotein(a) [apo(a)] is a glycoprotein with Mr approximately equal to 280,000 that is disulfide linked to apolipoprotein B in lipoprotein(a) particles. Elevated plasma levels of lipoprotein(a) are correlated with atherosclerosis. Partial amino acid sequence of apo(a) shows that it has striking homology to plasminogen. Plasminogen is a plasma serine protease zymogen that consists of five homologous and tandemly repeated domains called kringles and a trypsin-like protease domain. The amino-terminal sequence obtained for apo(a) is homologous to the beginning of kringle 4 but not the amino terminus of plasminogen. Apo(a) was subjected to limited proteolysis by trypsin or V8 protease, and fragments generated were isolated and sequenced. Sequences obtained from several of these fragments are highly (77-100%) homologous to plasminogen residues 391-421, which reside within kringle 4. Analysis of these internal apo(a) sequences revealed that apo(a) may contain at least two kringle 4-like domains. A sequence obtained from another tryptic fragment also shows homology to the end of kringle 4 and the beginning of kringle 5. Sequence data obtained from two tryptic fragments show homology with the protease domain of plasminogen. One of these sequences is homologous to the sequences surrounding the activation site of plasminogen. Plasminogen is activated by the cleavage of a specific arginine residue by urokinase and tissue plasminogen activator; however, the corresponding site in apo(a) is a serine that would not be cleaved by tissue plasminogen activator or urokinase. Using a plasmin-specific assay, no proteolytic activity could be demonstrated for lipoprotein(a) particles. These results suggest that apo(a) contains kringle-like domains and an inactive protease domain.
 ...
PMID:Partial amino acid sequence of apolipoprotein(a) shows that it is homologous to plasminogen. 347 6

The authors report their experience in fibrinolytic therapy with Urokinase in acute myocardial infarction. There were 3 groups of treatment: 100 patients with intracoronary fibrinolytic therapy; 77 patients with peripheral venous fibrinolytic administration; 31 patients with conventional therapy. The 3 groups underwent, between 21 and 28 days after the acute event, a coronarographic examination to evaluate the persistence of patency of the vessels involved in the myocardial infarction. The short term results show that the fibrinolytic therapy (with the limitations due to the hemorrhagic complications associated with the use of Urokinase), especially via intracoronary, is significantly more useful and reliable than conventional therapy, which appears unsatisfactory. Therapeutic failures are probably due to diffuse atherosclerosis of the vessel and/or to the old age of the thrombus.
 ...
PMID:[Fibrinolytic therapy in acute myocardial infarction. Coronarographic evaluation of short-term results]. 376 65


1 2 3 4 5 6 7 8 9 10 Next >>