Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020473 (hyperlipidemia)
 15,891 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A case of acute intestinal vascular necrosis in a 19-year-old user of oral contraceptives (OCs) is described, and hypotheses explaining the digestive complications of synthetic estrogens are reviewed. The patient had originally presented with a violent gastric pain that subsequently spread to the entire abdomen. An abrupt worsening of her condition involved cardiovascular collapse associated with a peritoneal syndrome, vomiting and dehydration, and hyperleukocytosis. Emergency opening of the peritoneum was followed by evacuation of a large quantity of fetid gas and alimentary debris, and observation of a completely necrosed stomach. A careful lavage of the entire intestinal cavity led to temporary improvement, but it became clear during an attempt at gastrectomy that further treatment would be unavailing and the patient died shortly thereafter. Estrogens were believed to be responsible for the digestive necrosis because it occurred in a young woman who had used an estrogen-rich OC for 3 years and who smoked; a hapatic biopsy confirmed the diagnosis. No traces of other risk factors such as hypertension, hyperlipidemia, diabetes, neoplasia, or obesity were observed. Recent publications indicate that OCs are responsible for a certain number of digestive problems, which may include acceleration of intestinal transit, severe diarrhea, rectorrhagia, ischemic or ulcerative colitis, intestinal infarct which is usually localized, and hepatocellular problems ranging from moderate hepatic insufficiency to malignant tumor and Budd-Chiari syndrome. OCs do not modify hemodynamic regimes, but they may cause elevation of fibrinogen and thrombin, diminution of antithrombin III acitivty, increased platelet adhesivity, and decreased fibrinolysis leading to hypercoagulability. These modifications in hemostasis occur in all OC users and are not statistically correlated with occurence of thrombotic accidents. OCs are probably responsible for parietal vascular lesions; experimental injection of synthetic estrogens is associated with both arterial and venous lesions. The most characteristic anomaly is at the level of the intima, with proliferation of smooth muscle cells and increased conjunctive tissue fibers associated with proliferation of the media or the endothelium. The absence of lipid deposits, the simultaneous appearance of arterial and venous lesions, and other evidence argues against and atheromatous origin of parietal lesions. A significant correlation has been found between high levels of anti-synthetic ethinyl estradiol antibodies and the presence of vascular lesions. It is hypothesized that these circulating immune complexes penetrate the vascular walls of OC users and produce lesions, which may depend on factors such as smoking.
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PMID:[Digestive complications of oral contraceptives: a case of extensive digestive necrosis in a young woman]. 647 54

In 13 type II hyperlipidemics (10 males and 3 females; mean age 50.2 +/- 10.6 years), in 10 type IV hyperlipidemics (7 males and 3 females; mean age 51 +/- 13.3 years) and in 23 healthy age- and sex-matched controls, the following parameters were measured: plasma cholesterol; plasma TG; plasma C-HDL; VLDL, separated in a preparative ultracentrifuge; C-LDL; Apo B, with immunoelectrophoretic method; platelet sensitivity to prostacyclin; TXB2 formation in PRP; TXB2 in serum. This study provides evidence for: 1. Reduced platelet sensitivity to prostacyclin, more evident in type II hyperlipidemia that provides an additional mechanism involved in increased platelet aggregation found in type II hyperlipidemia. 2. Enhanced TXB2 formation in PRP after thrombin stimulation (664.65 +/- 142.18 pmol/10(8) platelets) only in type II hyperlipidemics and such enhanced formation was positively correlated to C-LDL (r = 0.53; p less than 0.05) and to Apo B (r = 0.62; p less than 0.05); serum TXB2 formation rate was also increased in type II hyperlipidemia.
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PMID:Platelet sensitivity to prostacyclin and thromboxane production in hyperlipidemic patients. 675 32

The performance of a fluorometric heparin assay system was evaluated. The system indirectly measures heparin by its inhibition of thrombin protease action on a synthetic substrate. Our results confirm that within the range of heparin concentrations recommended by the manufacturer, i.e., 0.1-0.8 units/ml, there is an excellent correlation between expected and observed values. Within-day coefficients of variation range from 1% to 2.6%; the between-day coefficient of variation is 6.5. The accuracy of the assay diminishes under 0.1 units/ml. The assay is not influenced by bilirubin, hemolysis, fibrin split products, or lipemia. Results can be generated in less than 5 min. Possible drawbacks are the wide range of acceptability for the supplied heparin standard, and the frequency of pipetting involved.
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PMID:Measurement of plasma heparin levels using a fluorometric assay. 685 52

This article reviews the experimental and clinical evidence regarding heparin therapy in the prophylaxis of coronary heart disease. The actions of heparin take place at the vascular endothelium where injected heparin concentrates, and within the bloodstream. At the endothelium heparin acts to prevent endothelial injury, prevent thrombin generation, prevent platelet adhesion to endothelium, and to decrease uptake of serum lipoproteins. Within the bloodstream heparin increases lipoprotein lipase activity and reduces the concentration of atherogenic very low-density lipoproteins. The reduction in lipemia enhances oxygen transfer from blood to the tissues, and decreases thrombin or ADP-induced platelet aggregation. Heparin increases the concentration of high-density lipoproteins. It decreases hypercoagulability and inhibits overactivation of serum complement. Heparin reduced atherosclerosis in most studies in cholesterol-fed animals. In human subjects who had a myocardial infarct at least one year before the onset of treatment, long-term intermittent heparin therapy significantly decreased cardiovascular deaths as compared to control groups.
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PMID:Heparin and atherosclerosis. A review of old and recent findings. 698 41

The platelet lipid biosynthesis in relation to platelet aggregation and lipemia was studied by 14C-acetate and mevalonate incorporation into platelets of seventeen women without medication and of eighteen women using a low estrogen oral contraceptive. The lipid biosynthesis was significantly increased by 59% (mevalonate) and 38% (acetate) in women on oral contraceptives. From mevalonate, lipid synthesis was increased mostly in the lanosterol-dihydrolanosterol fraction (p less than .01). From acetate, lipid synthesis was significantly enhanced in all the lipid classes. In the oral contraceptive group, the response of platelets to thrombin aggregation was only slightly higher, but HDL-cholesterol was significantly lower. However, in the women using oral contraceptives, the percentage of abnormal values in HDL-cholesterol, thrombin-aggregation and acetate incorporation into lanosterol was similar. Thus, more than 40% of the women studied here, using low estrogen oral contraceptives, presented an increase in platelet lipid biosynthesis, especially in the lanosterol-dihydrolanosterol fraction, which was significantly correlated (p less than .05) with the response of their platelets to thrombin-induced aggregation.
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PMID:Biosynthesis of platelet lipids in relation to aggregation in women using oral contraceptives. 711 49

Intact arterial vessel wall is not thrombogenic. Disorders of the endothelium in connection with pathological coditions such such as atherosclerosis, hyperlipidaemia, hypertension and hyperuricemia induce interaction of surfaces of high thromboplastic activity with the blood stream. In such situations local formation of thrombin will take place immediately. Evidence is presented for the essential and unique activation of the extrinsic pathway of the plasmatic coagulation system. The local formation of thrombin at pathologically altered arterial wall seems to be an important trigger for arterial thrombosis and haemostasis. It could be that in vivo the initial step of thrombogenesis depends upon the formation of the activator complex between tissue-thromboplastin and factor VII.
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PMID:Thromboplastic activity of human arterial walls and its interaction with the plasmatic coagulation system. 744 Nov 81

To assess the risk factors for atherosclerosis in Werner's syndrome (WS), coagulation/fibrinolytic system parameters and lipid levels were investigated in 9 non-smoker patients with WS and compared with normal control values (N). The levels of thrombin antithrombin III complex (p < 0.05), D-dimer (p < 0.05), tissue plasminogen activator (p < 0.005) and PA inhibitor 1 (p < 0.01) were significantly increased, while the level of thrombomodulin (p < 0.005) in the fasting plasma was significantly decreased in the WS cases compared with N. Lipid profiles confirmed that 8 of the 9 patients were of hyperlipidemia type IIb, 7 had hyperinsulinemia and 5 fulfilled the criteria for clinical diabetes mellitus. The hypercoagulable condition suggested the existence of multiple risk factors for atherosclerosis in WS in addition to the previously reported hyperinsulinemia and hyperlipidemia.
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PMID:Hypercoagulable state indicates an additional risk factor for atherosclerosis in Werner's syndrome. 749 61

Prothrombin fragment 1.2 (F1.2) is an activation peptide generated during a critical event of blood coagulation, the conversion of prothrombin to thrombin. As a marker of thrombin generation, F1.2 has clinical potential in assessing thrombotic risk and monitoring anticoagulant therapy. In developing a highly specific, monoclonal antibody-based immunoassay of human plasma F1.2, we generated six murine anti-F1.2 monoclonal antibodies, using as immunogen a synthetic peptide (sequence: CGSD-RAIEGR) similar to the unique carboxyl terminus of F1.2. Each antibody bound F1.2 but not prothrombin. Epitope mapping studies with one antibody (5-3B) showed that optimum binding required six to eight amino acids plus a terminal arginine to emulate the F1.2 carboxyl terminus. A quantitative sandwich ELISA for human plasma F1.2 was configured with monoclonal antibody 5-3B as the capture antibody and peroxidase-labeled polyclonal antibodies to the F1.2 amino-terminal region as detector antibodies. Calibrators were prepared by adding purified F1.2, 0-10 nmol/L, to F1.2-depleted plasma. Assay characteristics included the following: mean (+/- SD) analytical recovery of 98% +/- 13%; no interference from lipemia, hemolysis, icterus, or thrombolytic agents; 0.08 nmol/L sensitivity; and mean intra- and interassay imprecision (three lots) < 12% at both low and high concentrations of F1.2.
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PMID:Monoclonal antibodies specific for prothrombin fragment 1.2 and their use in a quantitative enzyme-linked immunosorbent assay. 847 48

By the mediation of receptors in the endothelium, bradykinin, histamine, and thrombin--besides platelet-derived substances such as adenosine diphosphate and triphosphate (ADP, ATP) and serotonin--play an essential physiological role in the activation of the protective metabolic process in the endothelium, which is so important to vessel dilatation. The described process is attenuated by pathologic conditions such as e.g. hyperlipidaemia and hypertension. Furthermore, in the case of experimental hypertension, the production of contractile endothelial factors, which weaken the effect of the vasodilatory endothelial factors, is likely to increase. Obviously, an efficient antihypertensive therapy prevents from this endothelial dysfunction, at least in animal experiments.
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PMID:[Receptor-mediated endothelial vascular regulation (brief report)]. 818 16

To clarify age-related and lipid-related hemostatic abnormalities in the elderly, we measured the plasma levels of active PAI-1 antigen (aPAI-1), tPA-PAI-1 complex (TPC), plasminogen, alpha 2-plasmin inhibitor (alpha 2-PI), plasmin-alpha 2-PI complex (PIC), and D-dimer, together with the plasma levels of fibrinogen, factor VII (F VII), and thrombin-antithrombin III complex (TAT) and the serum lipid levels in 68 hyperlipidemic and 82 normolipidemic elderly subjects. The aPAI-1 ratio was calculated as aPAI-1/(aPAI-1 + TPC). In the normolipidemic elderly subjects, plasma PIC and D-dimer levels were much higher when compared with healthy young controls, and there was also a decrease in plasma plasminogen and alpha 2-PI levels, an increase in plasma TPC levels, and high plasma F VII and fibrinogen levels. In elderly subjects with type IIb hyperlipidemia, both the plasma aPAI-1 level and the aPAI-1 ratio were significantly increased, while the plasma PIC and D-dimer levels were reduced despite higher plasma F VII, fibrinogen and TAT levels. Both serum total cholesterol and triglyceride levels were correlated positively with plasma F VII and TAT levels and with the TAT/PIC ratio, while only serum triglyceride levels showed a positive correlation with plasma TPC and aPAI-1 levels and with the aPAI-1 ratio. Thus, an increase of fibrinolytic activity appears to occur as part of normal aging to balance the increase of procoagulant activity. However, an imbalance between thrombin activity (increased procoagulant activity) and plasmin activity (hypofibrinolysis) appears to occur in elderly individuals with hyperlipidemia, perhaps resulting in a predisposition to thromboembolic disease.
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PMID:Lipid-related hemostatic abnormalities in the elderly: imbalance between coagulation and fibrinolysis. 829 90


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