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)

Effects of isomers of chondroitin sulfate on atherosclerosis were clinically compared, based on sulfate linkage and the amount of sulfate, by using chondroitin 4-sulfate, chondroitin 6-sulfate and chondroitin polysulfate. Fourty eight age-matched atherosclerotic subjects were selected from a home for the elderly in order to the treatment with the agents. The isomers of chondroitin sulfate were given a daily dose of 4.5 g perorally. During the experimental period for 64 months, mortality, serum cholesterol, thrombus-formation time and thrombus weight were examined. The result obtained was as follows: mortality in the groups treated with the isomers of chondroitin sulfate was less than the age-matched untreated control group. Serum cholesterol value in the group treated by the isomers of chondroitin sulfate, chondroitin polysulfate group in particular, fell lower than the pre-treatment value. Thrombus formation time prolonged 150% in the group treated with chondroitin polysulfate over the untreated control group and the resultant thrombus weight was reduced in the treated group. Thus, these data indicated that the isomers of chondroitin sulfate are clinically effective on the treatment of atherosclerosis in the order of chondroitin polysulfate, chondroitin 4-sulfate and/or chondroitin 6-sulfate.
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PMID:Comparative study of the effects of chondroitin sulfate isomers on atherosclerotic subjects. 39 71

A six year old girl complained of sudden severe headache, became hemiplegic and unconscious. A right carotid arteriogram revealed an obstruction of the right anterior cerebral artery and many sulvian branches. Death occurred four days later. At autopsy, a recent softening of nearly all the right middle cerebral arterial territory was found. Thrombus filled the sylvian artery and its main branches. Histologic examination of the vessel walls showed a dissecting infiltration of blood between the internal elastic lamina and the media. This particular form of dissecting aneurysm, occurring in young subjects, in the absence of atherosclerosis, high blood pressure and idiopathic medial necrosis, represents a distinct medial necrosis, represents a distinct nosologic entity that has been called "Obstructive parietal hemodissection of intracranial vessels." The pathogenesis of the disease is unknown: trauma has been mentioned, also congenital defects in the elastic lamina or other morphologic abnormalities of that lamina.
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PMID:[Obstructive parietal hemodissection of the intracranial vessels, a particular form of dissecting aneurysm]. 83 66

Adding less than 0.5% w/w of culture material of strain MRC 826 of the fungus Fusarium moniliforme to a carbohydrate diet low in fat resulted in an atherogenic plasma lipid profile in a non-human primate. Simultaneously increased plasma fibrinogen and activity of blood coagulation factor VII could enhance atherogenesis. This unique potential for promotion of atherosclerosis was probably secondary to chronic hepatotoxicity as indicated by liver fibrosis and elevated cholesterol, albumin and the enzymes AST, ALT, LD, GGT and ALP in serum. The cholesterol and enzymes responded in proportion to the calculated doses of fumonisin mycotoxins in the F. moniliforme MRC 826 cultures. Fumonisins are water soluble and heat stable. Thrombotic, hepatotoxic, carcinogenic and cerebral effects of MRC 826 culture material and fumonisins are well known in non-primates. The estimated fumonisin concentrations tested fall within a range due to natural contamination of human foods. The results suggest that all maize grain products should be analysed for fumonisins.
Atherosclerosis 1992 May
PMID:Atherogenic effects in a non-human primate of Fusarium moniliforme cultures added to a carbohydrate diet. 163 55

Thrombotic occlusion is the major cause of myocardial infarction (MI), and fibrin accumulation appears to play a significant role in development of atherosclerotic lesions. Any factor that reduces the lysis of fibrin may thus increase the risk of MI, and it has been suggested that this accounts for the atherogenicity of the lipoprotein variant Lp(a). The characteristic feature of Lp(a) is an apoprotein which is homologous with part of the plasminogen molecule, and experiments in vitro suggest that it interferes with uptake and activation of plasminogen on cell surfaces and fibrin. The presence of Lp(a) also seemed to offer an explanation for the apparent absence of plasminogen from 70-80% of intimal samples. We have compared the levels of Lp(a) and plasminogen in normal intima and atherosclerotic lesions. In aortic intima there was no relation between Lp(a) and plasminogen, which was absent in some samples with no Lp(a), and present in others with high levels. In intravascular thrombi plasminogen was present at a rather constant concentration (16.3 +/- 4.6 micrograms/100 mg wet tissue), whereas Lp(a) varied over a 100 fold range (0-104 micrograms/100 mg). Plasminogen binds to fibrin and is activated on the fibrin clot, so levels in extracts may not fully represent Lp(a)/plasminogen interactions. After extraction the residual tissues and thrombi were treated with 1 M epsilon-aminocaproic acid (epsilon-aca) to elute lysine-bound components. Lp(a) was eluted from all but one intimal sample, confirming previous findings on its binding to fibrin in lesions, but there was no relation between the amounts of Lp(a) and plasminogen in the tissue eluates. Paradoxically, in the thrombi there was a weak positive correlation between Lp(a) and plasminogen in epsilon-aca eluates (r = 0.504, P = 0.05). These results do not support the hypothesis that Lp(a) displaces plasminogen in vivo, but the large amount of Lp(a) eluted by epsilon-aca suggests that its atherogenicity resides in preferential binding to fibrin, leading to increased lipid accumulation in lesions.
Atherosclerosis 1991 Aug
PMID:Does lipoprotein(a) (Lp(a)) complete with plasminogen in human atherosclerotic lesions and thrombi? 183 24

Epidemiological surveys show the clear association of hypertension with an increased risk of developing ischaemic heart disease. One method of quantifying atherosclerosis is to measure, at necropsy, the percentage of the intimal surface of the coronary arteries or aorta which is occupied by raised plaques. When this is done in a large number of subjects the amount of intimal involvement in any particular geographical population correlates directly with the frequency of ischaemic heart disease. In all these populations, whether at a high risk or low risk of developing ischaemic heart disease, hypertensive subjects have a greater intimal involvement by plaques than normotensive subjects. Thus, the increased risk in hypertension is, in part, mediated by possession of more plaques. Plaque growth is due to the accumulation of lipid from the plasma, the ingress of monocytes with their conversion to lipid filled foam cells and the formation of collagen by smooth muscle cells. Hypertension may act by altering endothelial function to potentiate all these processes. Mechanical stress on endothelial cells will evoke the formation of growth factors for smooth muscle cells. Plaque growth in man is also episodic due to the formation of thrombi; a proportion of these episodes are symptomatic producing acute myocardial ischaemia but the majority are silent leading to sudden plaque expansion. Thrombi over plaques are either due to endothelial denudation injury or more commonly due to the tearing of the cap of a plaque leading to deep intimal injury. Necropsy surveys of control populations show that subjects with hypertension have a greater frequency of recent plaque tears compared with normotensive subjects.
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PMID:Hypertension and atherosclerotic (ischaemic) heart disease. 194 81

Vascular tissue obtained using a directional percutaneous atherectomy device was examined microscopically. Tissue was obtained from coronary arteries without prior instrumentation (primary lesions, n = 31), aortocoronary saphenous vein bypass grafts with primary lesions (n = 8), coronary arteries with lesions developing after prior balloon angioplasty or mechanical atherectomy (restenotic lesions, n = 30) and vein bypass grafts with restenotic lesions (n = 4). Primary lesions were characterized by dense intimal fibrosis with necrotic debris (83% of intimal tissue) and foam cells typical of atherosclerosis. These lesions frequently contained cholesterol crystals (45% of coronary arteries, 50% of vein grafts) and calcium deposits (65% of coronary arteries, 38% of vein grafts). Restenotic lesions were characterized by an increased proportion of loose fibroproliferative tissue (45% of coronary artery intima, 35% of vein graft intima). Immunohistochemical stains confirmed this proliferative tissue to be primarily smooth muscle cells. Thrombus was rarely observed. Comparison of resected tissues indicated that dense fibrosis and necrosis are significantly more common in primary than in restenotic lesions (83% versus 56% of intimal tissue, p = 0.0005), whereas smooth muscle cell hyperplasia is more common in restenotic than in primary lesions (44% versus 17% of intimal tissue, p less than 0.0005). Partial-thickness resection of medial tissue or full-thickness resection of media with associated adventitial tissue occurred in 27 (56%) of 39 primary atheromatous lesions and 16 (47%) of 34 restenotic lesions; subintimal tissue obtained from primary lesions appeared identical to that obtained from restenotic lesions. These data indicate that the histopathologic characteristics of the neointimal layer of restenotic lesions differ from those of the intimal layer of primary atherosclerotic lesions.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Differential histopathology of primary atherosclerotic and restenotic lesions in coronary arteries and saphenous vein bypass grafts: analysis of tissue obtained from 73 patients by directional atherectomy. 199 2

Current findings and controversies between oral contraceptives (OCs) and cardiovascular disease and cancers. Specifically, venous thromboembolism, stroke, myocardial infarction, (MI), atherosclerosis, breast cancer, cervical cancer, endometrial cancer, and ovarian cancer are reviewed. The concentration in the literature is on higher dose estrogen (at least 50 mg) studies which suggest that there is with current users, particularly older women who smoke, a risk of myocardial infarction, venous thrombosis, and subarachnoid hemorrhage. Of the 11 case control studies and 4 cohort studies it appears that venous thrombosis increases in risk with an increase in estrogen content and remains constant for duration of use. However, definitive studies have not been completed on 50 mg doses of ethinyl estradiol (EE) and mestranol (ME). The actual individual risk may be small, 1/1000 current users/year. Thrombotic and hemorrhagic stroke in the 1970s had a risk of 37/100,000 users per year, mostly among smokers 35 years and older with predisposing medical conditions. It is suggested that although there were mixed findings between current and past users in the 1970s low dose current or past users are not substantially at risk. The pre-mid 1970 risk of MI was 7 and 67 cases/100,000 current users ged 30-39 respectively per year. The risk group is similar to stroke. Thrombosis seems to be responsible for the increased risk, rather than atherosclerosis. More data are needed on low preparations; however limited findings suggest little if any risk. There is no available data on the risk for coronary artery atherosclerosis due to OC use, even though 50% of all women die from atherosclerosis-related processes regardless of OC use. Non human primate studies, however, suggest that there may be a reduced risk, perhaps due to the presence of estrogen receptors in arterial endothelium and smooth muscles. Data clearly indicate that the overall risk of breast cancer pre and post 1950 is the same, but age may be a factor with younger OC users at risk; parity protects. The association for lifetime risk, however, cannot be determined since most use occurred in the 1960s. For cervical cancer, 8 found no increased risk and 9 did, and the suggestion is the 5 years use is related to increased risk. Biases related to sexual behavior confound control and analysis of data. The most common cancer in developing countries is cervical, which warrants greater Pap smear screening to reduce this preventable cancer. Protection from cancer of the endometrium occurs for 15 years following 12 months of OC use at a 40% reduced risk. A protected effect is also found for epithelial ovarian cancer, with a 40% risk reduction. It is concluded that health benefits of OCs far exceed the health risks.
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PMID:Long-term health risks and benefits of oral contraceptive use. 209 41

Rupture of an atherosclerotic plaque associated with partial or complete thrombotic vessel occlusion is fundamental to the development of ischemic coronary syndromes. Plaques that produce only mild-to-moderate angiographic luminal stenosis are frequently those that undergo abrupt disruption, leading to unstable angina or acute myocardial infarction. Plaques with increased lipid content appear more prone to rupture, particularly when the lipid pool is localized eccentrically within the intima. Macrophages appear to play an important role in atherogenesis, perhaps by participating in the uptake and metabolism of lipoproteins, secretion of growth factors, and production of enzymes and toxic metabolites that may facilitate plaque rupture. In addition, the particular composition or configuration of a plaque and the hemodynamic forces to which it is exposed may determine its susceptibility to disruption. Exposure of collagen, lipids, and smooth muscle cells after plaque rupture leads to the activation of platelets and the coagulation cascade system. The resulting thrombus may lead to marked reduction in myocardial perfusion and the development of an unstable coronary syndrome, or it may become organized and incorporated into the diseased vessel, thus contributing to the progression of atherosclerosis. In unstable angina, plaque disruption leads to thrombosis, which is usually labile and results in only a transient reduction in myocardial perfusion. Release of vasoactive substances, arterial spasm, or increases in myocardial oxygen demand may contribute to ischemia. In acute myocardial infarction, plaque disruption results in a more persistent thrombotic vessel occlusion; the extent of necrosis depends on the size of the artery, the duration of occlusion, the presence of collateral flow, and the integrity of the fibrinolytic system. Thrombi that undergo lysis expose a highly thrombogenic surface to the circulating blood, which has the capacity of activating platelets and the coagulation cascade system and may lead to thrombotic reocclusion. Measurements aimed at reversing the process of atherosclerosis via cholesterol reduction and enhanced high density lipoprotein activity are encouraging. Active research is being focused on the development of new antithrombotic tools, such as inhibitors of thrombin, thromboxane, and serotonin receptor antagonists, and monoclonal antibodies aimed at blocking platelet membrane receptors or adhesive proteins. These compounds may prove useful when immediate and potent inhibition of the hemostatic system is desired. Intensive research is still needed in the areas of pathogenesis and therapeutic intervention in atherosclerosis.
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PMID:Atherosclerotic plaque rupture and thrombosis. Evolving concepts. 220 64

Thrombi defined as intraluminal filling defects detected by angiography were identified in 30 patients (29 in the carotid system, one in the vertebral artery). Stroke was the presentation ipsilateral to the thrombus in 22 patients (12 had previous transient ischemic attacks), transient ischemic attacks occurred alone in seven cases, and one patient was asymptomatic. Angiography revealed a severe stenosis in association with the thrombus in 23 patients, a moderate stenosis in four patients, and, in the three patients with only minimal stenosis presumably due to atherosclerosis, there was evidence for a coagulopathy. Sixteen of the 30 patients were operated on urgently, 10 within 24 hours of detection of the thrombus. Twelve of these 16 surgical patients were given anticoagulation before surgery. At endarterectomy, thrombus was identified in 11 of the 14 surgical patients in whom the thrombus was accessible; the other two surgical patients had intracranial thrombus only. In this group, four of 11 surgical patients with accessible thrombi suffered perioperative episodes of new or larger infarction. Fourteen of the 30 patients initially received medical management with no complication. Eight of these 14 medical patients had repeat angiography; seven exhibited complete resolution of thrombus, and six of these seven patients subsequently underwent delayed endarterectomy for the stenosis. No thrombus was identified at surgery in any of the six. One of the six delayed surgery patients suffered a perioperative stroke. Although these numbers are small, reflecting the rarity of thrombus demonstrated by angiography, undetected thrombus is often found at endarterectomy. Its presence may increase operative risk.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Intraluminal thrombus in the cerebral circulation. Implications for surgical management. 337 59

Morphological changes in aortocoronary vein grafts are described in two cases; one dying 5 hours post operatively and the other reoperated 8 months after aortocoronary bypass surgery for graft occlusion. Occlusive thrombi and fibrin deposition on the intimal surface and a focal inflammatory process in the wall of the vein grafts were found in the former. Thrombotic encrustation and organization similar to the manifestations of the thrombogenic theory of atherosclerosis were demonstrated in the latter.
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PMID:Inflammatory reaction as an occlusive mechanism in aortocoronary bypass grafts? 348 20


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