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)

Platelet-derived growth factor (PDGF) and beta-thromboglobulin (beta-TG) are released from alpha granules during platelet activation. PDGF may play a role in the development of atherosclerosis and the late restenosis after percutaneous transluminal coronary angioplasty (PTCA). The effect of acetylsalicylic acid (ASA) on PDGF release was studied in healthy volunteers before and twelve hours after ingestion of 300 mg ASA. PDGF, beta-TG, and thromboxane B2(TxB2) were measured by radioimmunoassay (RIA) in serum and in platelet rich plasma (PRP) after submaximal stimulation with collagen. TxB2 decreased significantly from 0.9 +/- 0.3 ng/(mL x 10(6) platelets) to 0.006 +/- 0.005 ng/(mL x 10(6) platelets) (mean +/- SD) in serum after ASA ingestion while PDGF and beta-TG remained unchanged. Measurements in PRP after stimulation with collagen showed a significant decrease in PDGF (from 21.5 +/- 1.4 pg/(mL x 10(6) platelets) to 1.8 +/- 4.1 (pg/mL x 10(6) platelets), in beta-TG (from 21.0 +/- 13.3 ng/(mL x 10(6) platelets) to 2.2 +/- 1.4 ng/(mL x 10(6) platelets)) and in TxB2 (from 143.6 +/- 80.7 pg/(mL x 10(6) platelets) to 0.5 +/- 0.6 pg/(mL x 10(6) platelets)) after treatment with ASA. In conclusion low-dose ASA inhibits collagen-induced release of both beta-TG and PDGF in PRP and TxB2-synthesis in PRP and serum.
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PMID:Platelet-derived growth factor release and antiplatelet treatment with low-dose acetylsalicylic acid. 834 80

Many studies have shown increased platelet activation in patients with coronary artery, cerebrovascular and peripheral vascular diseases. However, the temporal relationship between platelet activation and arterial atherosclerosis is unclear. To answer this basic question, we measured the plasma concentrations of two specific platelet activation markers, beta-thromboglobulin (beta TG) and platelet factor 4 (PF4) in 459 cases with increased carotid arterial wall thickness and 459 age-, sex-and race-matched controls selected from a cohort of 15,800 men and women, aged 45-64 who participated in the Atherosclerosis Risk in Communities Study. These participants had no acute vascular symptoms or known cardiovascular disease. The mean values of beta TG and PF4 were significantly higher in cases than in controls. However, when analyzed by quartiles using conditional logistic regression, only beta TG exhibited a significant association with carotid wall thickness, while PF4 did not. The odds ratio (OR) determined by multivariate logistic regression analysis was significantly higher for the uppermost quartile of beta TG (OR=1.7, 95% CI 1.1-2.5) compared to the lower 3 quartiles. This OR was 2.3 in white men (95% CI 1.2-4.2), 1.4 in white women (95% CI 0.6-3.0) and 1.0 in blacks (95% CI 0.4-2.5). This study indicates that plasma beta TG may be useful as a marker for early atherosclerosis in middle aged adults, particularly in white men. It also suggests that platelet activation has an independent role in the pathogenesis of atherosclerosis, although the possibility that this may be a response to carotid atherosclerosis cannot be excluded.
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PMID:Correlation of specific platelet activation markers with carotid arterial wall thickness. 857 26

The platelet factor 4 (PF4) mobilisation properties of low molecular weight heparin (Fraxiparine, Sanofi Winthrop, France) in young survivors of myocardial infarction (YSMI) and healthy volunteers have been investigated. The study group consisted of 42 YSMI less than 44 years old, all of them with angiographically proven occlusive coronary artery disease, studied 6 to 24 months after the acute event. The control group was composed of 30 healthy men of similar age. Subjects from the study and control groups were allocated to the following subgroups: those receiving 60 or 120 IU/kg b.w. of standard heparin (Polfa Kutno, Poland) and those receiving 60, 120 or 180 IC anti-Xa U/kg b.w. of low molecular weight heparin (Fraxiparine, Sanofi Winthrop, France) as a single intravenous injection. Additionally, in five YSMI patients the influence of prolonged aspirin administration (0.3g daily for more than 30 days) on the Fraxiparine mobilsable pool of PF4 and beta-thromboglobulin (beta-TG) concentration in the plasma was determined after injection of 180 IC anti-Xa U/kg b.w. of the drug. The PF 4 and beta-TG concentration in the plasma was evaluated using enzyme immunoassay methods before heparin or Fraxiparine intravenous injection and 2, 5, 10, 20, 30 and 60 min after. In both, the control and YSMI groups baseline PF4 levels were found to be normal. Moreover, similar marked dose-dependent increases of PF4 concentration in the plasma measured after 60 and 120 IU/kg b.w. of heparin as well as after 60 and 120 IC anti-Xa U/kg b.w. of Fraxiparine was found. The administration of 120 IU/kg b.w. of heparin resulted in a reduced rise in plasma PF 4 in YSMI as compared to healthy controls. The same phenomenon was observed when 180 IC anti-Xa U/kg b. w. of Fraxiparine was injected intravenously. In YSMI treatment with aspirin had no influence on the Fraxiparine mobilisable pool of PF 4 or the beta-TG concentration in the plasma. These results suggest that mobilisable pool of platelet factor 4 in young survivors of myocardial infarction derives from the "nonplatelet pool" and that reduction of heparin- or Fraxiparine-releasable pool of PF4 may reflect an impaired endothelium function, probably due to atherosclerosis.
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PMID:Low molecular weight heparin and the heparin mobilisable pool of platelet factor 4 are reduced in young survivors of myocardial infarction. 886 11

There is mounting evidence that antioxidants may help to prevent coronary heart disease and modulate some thrombotic events such a platelet adhesion. However, the effects of antioxidant supplementation on platelet function in vivo are controversial. A double-blind, randomised, placebo-controlled study was performed on 40 healthy volunteers (20-50 years) supplemented daily with vitamin E (300 mg), vitamin C (250 mg) or beta-carotene (15 mg) for 8 weeks. Platelet function was assessed by platelet aggregation induced by ADP, arachidonic acid or collagen, platelet responsiveness to the inhibitor PGE1, beta-thromboglobulin release and ATP secretion. Supplementation with vitamin E resulted in a significant increase in platelet alpha-tocopherol level (+68%) reflecting closely the increase in plasma alpha-tocopherol level (+69%). Platelet function was significantly decreased by vitamin E as revealed by the decreased platelet aggregation in response to ADP and arachidonic acid, the increased sensitivity to inhibition by PGE1, the decreased plasma beta-thromboglobulin concentration and the decreased ATP secretion. Supplementation with vitamin C did not affect platelet function significantly although a trend towards a decreased platelet aggregability and an increased sensitivity to the inhibitor PGE1 were observed. No significant changes in platelet function occurred after supplementation with beta-carotene. In conclusion, supplementation of healthy volunteers with vitamin E decreased platelet function whereas supplementation with vitamin C or beta-carotene had no significant effects.
Atherosclerosis 1997 Jan 03
PMID:The influence of antioxidant nutrients on platelet function in healthy volunteers. 905 Dec 2

The present study was conducted to determine whether alimentary lipemia alters platelet activity in vivo. Normolipidemic volunteers were given a fatty meal and platelet function was assessed before, and 3 and 6 h after the meal. Platelet aggregability and secretion was determined using whole blood flow cytometry (expression of platelet P-selectin and fibrinogen binding), filtragometry ex vivo (reflecting platelet aggregability in vivo) and by measurements of platelet specific products in plasma (beta-thromboglobulin and platelet factor 4). Plasma triglycerides increased from 0.8 (0.6:1.1; median, 25th and 75th percentiles) to 1.7 (1.0:2.3) mmol/l at 3 h and returned to baseline after 6 h (P < 0.001, one-way ANOVA). Apo B-100 and apo B-48 were both markedly increased 3 h postprandially in the Sf 60-400 fraction (large VLDLs, P < 0.001 for both), whereas the Sf 20-60 (small VLDLs) and Sf 12-20 fractions (IDL) did not change. The platelet function assessments revealed that the percentage of platelets expressing P-selectin increased by 40% (5%; 64%) after 3 h and by 51% (- 7%; 85%) 6 h postprandially in unstimulated samples (P < 0.05 for both). In samples stimulated by ADP in vitro P-selectin expression increased by 45% (6%; 58%) after 3 h and by 30% (12%; 58%) (P<0.01 for both) after 6 h at 0.1 microM. Platelet P-selectin expression was less influenced at higher ADP concentrations. The plasma levels of beta-thromboglobulin (approximately 20 ng/ml) and platelet factor 4 (approximately 0.3 ng/ml) were not affected by the fat load. Flow cytometric analyses of fibrinogen binding and filtragometry measurements also failed to reveal any postprandial alterations. The present finding of enhanced platelet P-selectin expression suggests that platelets are mildly sensitized postprandially. Whether this is of importance for thrombus formation and atherosclerosis needs to be studied further.
Atherosclerosis 1998 Mar
PMID:Alimentary lipemia enhances the membrane expression of platelet P-selectin without affecting other markers of platelet activation. 956 42

The purposes of this study were to investigate the association between carotid atherosclerosis and hemostatic markers, and to elucidate the difference in hemostatic markers between intima-media thickening and plaque formation in patients with cerebral small artery disease. We investigated carotid atherosclerosis by assessing diffuse intima-media thickness measurements and localized plaque using B-mode ultrasonography, and we measured the concentrations of plasma fibrinogen, beta-thromboglobulin and platelet factor 4 as markers for platelet activation, and the activity of plasma von Willebrand factor as a marker for endothelial damage. The intima-media thickness was significantly associated with age, male sex, the concentrations of plasma beta-thromboglobulin and platelet factor 4, and the activity of plasma von Willebrand factor. The plaque score showed a significant association with male sex, the concentration of fibrinogen, and the activity of plasma von Willebrand factor. These results may indicate that underlying mechanisms are not the same between the intima-media thickness and plaque formation. We suggest that hemostatic markers could reflect the severity of carotid atherosclerosis in patients with cerebral small artery disease, and that preventive antiplatelet therapies against brain infarction might be necessary for patients with severe carotid atherosclerosis.
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PMID:Association between carotid atherosclerosis and hemostatic markers in patients with cerebral small artery disease. 960 19

VEGF-C is a recently characterised endothelial growth factor structurally related to vascular endothelial growth factor (VEGF). We studied the expression of VEGF-C and VEGF in the cells of peripheral blood and in the umbilical cord blood CD 34+ cells, representing haematopoietic progenitor cells. Expression of VEGF-C was detected in the CD34+ cells. In peripheral blood VEGF-C mRNA was restricted to platelets and T-cells. In contrast to the expression pattern of VEGF-C, VEGF mRNA was detected in all peripheral blood cell fractions studied, and also in CD34+ cells. VEGF-C mRNA was also detected in fresh bone marrow samples of acute leukaemia patients, but the expression did not show lineage specificity. VEGF-C and VEGF polypeptides were present in platelets and they were released from activated platelets together with the release of beta-thromboglobulin, suggesting that VEGF-C and VEGF reside in the alpha-granules of platelets. VEGF-C and VEGF, released from activated platelets, may have a role in angiogenesis during wound healing, and possibly also in other pathological conditions, such as atherosclerosis, tumour growth, and metastasis formation.
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PMID:Peripheral blood platelets express VEGF-C and VEGF which are released during platelet activation. 968 5

Increased inflammatory activity and platelet activation have been associated with an increased risk of cardiovascular (CV) events in epidemiological studies, but their prognostic importance in patients with stable angina pectoris is less well established. The Angina Prognosis Study in Stockholm (APSIS), comprised 809 patients (2766 patient years) with stable angina pectoris on double-blind treatment with verapamil or metoprolol. Plasma levels of fibrinogen and orosomucoid (an acute phase reactant), white blood cell counts (WBC), platelet counts and the urinary excretion of beta-thromboglobulin (reflecting platelet secretion), were related to the risk of CV death (n=36), non-fatal myocardial infarction (MI) (n=30) or revascularization (n=99) in a subgroup of 782 patients. Verapamil and metoprolol had only minor effects on the inflammatory variables. In multivariate Cox regression analyses (adjusted for previous MI, hypertension, diabetes mellitus and smoking), fibrinogen and WBC were independent predictors of CV death or non-fatal MI, as well as the risk of revascularization. Orosomucoid did not carry any independent information. Platelet counts and urinary beta-thromboglobulin were not significantly related to CV prognosis. The treatment given did not significantly influence the prognostic impact of either fibrinogen or WBC. Fibrinogen and WBC were independent predictors of CV death or non-fatal MI as well as disease progression leading to revascularization in patients with stable angina pectoris. As fibrinogen is also an acute-phase reactant, the present findings indicate that inflammatory activity is involved in disease progression in stable angina pectoris.
Atherosclerosis 2000 Jan
PMID:Inflammatory and hemostatic markers in relation to cardiovascular prognosis in patients with stable angina pectoris. Results from the APSIS study. The Angina Prognosis Study in Stockholm. 1058 Jan 84

Recently, the first apheresis technique for direct adsorption of low-density lipoprotein (LDL) and lipoprotein(a) [Lp(a)] from whole blood (DALI) was developed that does not require a prior plasma separation. That markedly simplifies the extracorporeal circuit. The aim of the present study was to test the acute biocompatibility, efficacy, and selectivity of DALI apheresis. In a prospective clinical study, 6 hypercholesterolemic patients suffering from angiographically proven atherosclerosis were treated 4 times each by DALI. 1.3 patient blood volumes were treated per session at blood flow rates of 60-80 ml/min using 750 or 1,000 ml of polyacrylate/polyacrylamide adsorber gel. The anticoagulation consisted of an initial heparin bolus followed by a citrate infusion. The sessions were clinically essentially uneventful. Mean corrected reductions of lipoproteins amounted to 65% for LDL-cholesterol, 54% for Lp(a), 28% for triglycerides, 1% for HDL-cholesterol, and 8% for fibrinogen. The selectivity of lipoprotein removal was high. Cell counts remained virtually unchanged and no signs of hemolysis or clotting were detected. Cell activation parameters elastase, beta-thromboglobulin, interleukin-1beta, and IL-6 showed no significant increase. Complement activation was negligible. There was significant, but clinically asymptomatic, bradykinin activation in the adsorber with mean maxima of 12,000 pg/ml in the efferent line at 1,000 ml of treated blood volume. In conclusion, DALI proved to be safe, selective, and efficient for the adsorption of LDL-C and Lp(a), which simplifies substantially the extracorporeal therapy in hypercholesterolemic patients.
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PMID:DALI apheresis in hyperlipidemic patients: biocompatibility, efficacy, and selectivity of direct adsorption of lipoproteins from whole blood. 1071 59

To study the existence of platelet activation before the onset of cerebral infarction, the ultrastructural features of platelets (7-day survival) and coagulation-fibrinolytic markers (70-100-min life span) were measured 2-12 h (acute phase), 7 days (subacute phase) and 6 months (chronic phase) after onset in 18 patients with cerebral infarction. Seven patients with atherosclerosis but without cerebral infarction and eight healthy subjects were studied as controls. Ultrastructural study included folds, pseudopods, vacuoles and centralization in addition to immunochemical staining such as platelet peroxidase and fibrinogen. Furthermore, beta-thromboglobulin, platelet factor-4, thrombin antithrombin complex and alpha(2)-plasmin inhibitor plasmin complex were examined as coagulation-fibrinolytic markers. Ultrastructural study of circulating platelets demonstrated no difference between acute and chronic phases and little difference between cerebral infarction and atherosclerosis, although plasma coagulation-fibrinolytic markers showed an increase in cerebral infarction at the acute phase but no difference among the chronic phase of cerebral infarction, atherosclerosis and normal healthy subjects. It is considered that shape change in circulating platelets was caused by pre-existed atherosclerosis rather than the thrombotic event itself though coagulation-fibrinolytic markers were derived from the thrombotic event.
Atherosclerosis 2000 Nov
PMID:Possible existence of platelet activation before the onset of cerebral infarction. 1105 16


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