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)

Endothelial cells form the luminal vascular surface and thus have a central role in the regulation of coagulation. One important way in which endothelial cells control the clotting system is by regulating the expression of binding sites for anticoagulant and procoagulant factors on the cell surface. In the quiescent state, endothelial cells maintain blood fluidity by promoting the activity of numerous anticoagulant pathways, including the protein C/protein S pathway. After activation, as can be brought about by cytokines, the balance of endothelial properties can be tipped to favor clot formation through coordinated induction of procoagulant and suppression of anticoagulant mechanisms. Tumor necrosis factor suppresses the endothelial anticoagulant cofactor thrombomodulin and induces expression of the procoagulant cofactor tissue factor. Working in concert, these changes can allow fibrin formation to proceed in an inflamed focus but maintain blood fluidity in the surrounding area of normal vasculature. Recent studies suggest that similar changes in endothelial coagulant properties can be induced by advanced glycosylation end products, proteins modified by glucose that accumulate in the vasculature at a rapid rate in diabetic subjects, indicating the potential relevance of these mechanisms in diabetic vascular disease.
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PMID:Endothelium and regulation of coagulation. 206 Apr 25

The influence of a disturbed hemostasis as one of the causes of retinal or ciliary vascular occlusions is still controversial. Antithrombin III, protein C and its cofactor protein S were investigated in 25 patients; 14 of them with a retinal vein occlusion, five showed an occlusion of retinal arteries and six of ciliary arteries. Patients with a preceding thromboembolic disease were excluded from the investigations. The mean values (+/- SEM) of antithrombin III (12.1 IU/ml +/- 0.4), protein C (116% +/- 4), total protein S (102% +/- 3) and free protein S (46% +/- 2) were equivalent to the mean values of a normal population. Neither does a defect or a lack of coagulation inhibitors have an essential influence on the development of an isolated retinal or ciliary vascular occlusion nor does the local occlusive vascular disorder influence the activity of systemic inhibitors.
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PMID:[Inhibitors of blood coagulation in vascular occlusion of the retina and optic nerve]. 214 89

The present prospective follow-up study was made to study the effect of glycaemic regulation on levels of factor VII, protein C and protein S in 15 insulin-dependent diabetic patients without manifestations of vascular disease. Patients were tested before and after 8 weeks of 'metabolic' intervention, whereby a near-normoglycaemic state was achieved. At baseline, values of cross-linked fibrin degradation products (XL-FDP) and levels of 'total' protein S were significantly increased and protein C values were decreased in the diabetic patients when compared to control subjects, whereas levels of factor VII and 'free' protein S were near normal. After 'metabolic' intervention a decrease of all haemostatic parameters were recorded, however XL-FDP levels did not decline to control levels and the imbalance of factor VII and protein C persisted. When patients with newly diagnosed diabetes (n = 8) were compared to those with long-term disease (n = 7) higher levels of factor VII, protein C and protein S were recorded in the latter group before and after metabolic intervention; at baseline the differences reached statistical significance for factor VII and protein S, and remained significant for factor VII after metabolic intervention. Before and after intervention XL-FDP levels were higher in patients with newly diagnosed disease than in patients with long-term diabetes. The correlation analysis revealed positive correlations of factor VII, protein C and protein S to cholesterol and triglycerides, of protein S to all glycaemic control parameters, negative correlations of protein C to glucose, and of XL-FDP to factor VII, protein C and protein S. The results indicate an imbalance of haemostasis towards thrombophilicity in insulin-dependent diabetic patients, not completely correctable by glycaemic control.
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PMID:The effect of near-normoglycaemic control on plasma levels of coagulation factor VII and the anticoagulant proteins C and S in insulin-dependent diabetic patients. 253 36

Few studies have presented a thorough analysis of young adults with symptoms of arterial occlusive disease. To learn more about the possible risk factors of vascular disease playing a role in these young patients, we have reviewed all patients of 45 years of age and younger with symptoms of arterial occlusive disease who had been referred to our department between 1978 and 1987. Thirty-seven patients (28 males and 9 females) were included in the study. The mean age at which the first symptoms occurred was 34 years. Most patients presented with chronic arterial obliterations of the lower extremities (31/37, 84%). In addition, 4 patients showed signs of ischaemic heart disease. A strongly positive family history of arteriosclerosis was obtained from 13 patients (35%). Hypertension was present in 7 patients (19%), diabetes in three (8%) and nicotine abuse was found in 27 patients (73%). Fifty-four percent of the patients (20/37) had undergone vascular reconstructive surgery, 19% (7/37) underwent transluminal dilatation, and 3 had had subsequent treatment of newly developed lesions. For this study, all patients were recalled to the outpatient clinic. A complete case history was taken followed by a physical examination and ECG. Laboratory examinations were performed to analyse parameters of: (a) coagulation; (b) fibrinolysis; (c) fat- and (d) methionine metabolism. Clear-cut laboratory abnormalities were found in 33 patients (33/37, 89%). Coagulation parameters were abnormal in 11 patients (30%) (protein S deficiency: 3 pts). Fibrinolysis was impaired in 15 patients (40%).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:A prospective survey of risk factors in young adults with arterial occlusive disease. 274 53

With the continued accumulation of clinical and animal studies, it is becoming abundantly clear that the protein C anticoagulant pathway plays a critical role in the regulation of coagulation. Investigations also indicate that this pathway is intimately involved in the interaction of the coagulation and inflammatory systems. Although no direct information is presently available, the function of this pathway is likely depressed in the regions of atherosclerotic plaque. It is clear that monocytes accumulate in this region and release many growth factors and monokines that are capable of endothelial function perturbation. Perturbation of the protein C anticoagulant pathway is one viable mechanism for the hypercoagulable state in this disease. As indicated here, the endothelial cells of the vessel wall play a critical role in the initiation, and possibly expression, of this pathway. Any injury to these cells that affects the proper expression of thrombomodulin, synthesis of protein S, or Factor Va inactivation complex formation could potentially lead to a hypercoagulable state and thrombotic complications. As has been discussed, several inflammatory mediators are already known that fulfill the criteria of endothelial cell perturbants that may lead to such a state. What other entities might have similar effects, either directly or indirectly through induction of cytokines, is not known at this time. A more complete understanding of this critical pathway and the effects of vascular disease on it should lead to a better understanding of many diverse disease processes and potential therapeutic strategies in the future.
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PMID:Protein C and the endothelium. 284 10

The protein C anticoagulant pathway provides many new insights into control mechanisms for regulating coagulation. The observation that protein C deficiency is associated with thrombotic tendencies in the heterozygote (106-109) and early, lethal thrombosis in the homozygote (110, 111) points to the importance of the system as a major regulatory pathway. The complexity of the system has only recently begun to emerge. Thrombin activation of protein C at the endothelial cell surface requires not only the synthesis of thrombomodulin but the coupling of the receptor to a protein C binding site. It is reasonable to assume that an inherited or acquired deficiency in thrombomodulin might lead to thrombotic tendencies. This aspect of the system may explain, in part, the association between vascular disease and thrombosis. Once activated, protein C has an almost total dependence on protein S to express anticoagulant activity. (98) This suggests that deficiencies of protein S may also be associated with thrombotic tendencies. Protein S offers an additional intriguing property. Protein S, a regulatory protein of the coagulation system, is found both free and associated with C4BP, a regulatory protein of the complement system. The high affinity, very stable interaction between these components (85) suggests that the interaction is likely to be involved in regulation. (89) The importance of the interaction remains to be demonstrated, but clearly this is a potential direct link between major control proteins of the coagulation and complement system. Clinical studies suggest that protein C and/or thrombomodulin might be effective therapeutically. Certainly, protein C supplementation during the onset of oral anticoagulant therapy would be expected to circumvent the transient rapid decrease in protein C levels that may influence the early effectiveness of oral anticoagulants. (119) In addition to the systems clinical importance, protein C, its activation, and its function offer a variety of intriguing biochemical problems. For instance, how does thrombomodulin alter the specificity of thrombin? What is the protein C binding site on the cell surface, and what role does Factor Va or its degradation products play in the formation and regulation of this site? How does protein S facilitate activated protein C anticoagulant activity and what roles do membrane surfaces play in this system? What role does beta-hydroxyaspartic acid play in protein C activation and function? How does activated protein C influence fibrinolytic activity? The answers to these questions will undoubtedly add to our understanding of the fundamental mechanisms involved in regulating blood coagulation.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Protein C. 609 83

The authors investigated the behaviour of some markers of the haemostatic balance in a group of patients with acute focal cerebral vasculopathy. The series consists of 70 female patients (mean age: 61 +/- 5), 25 of whom suffering from TIA and 45 from thrombotic stroke; 40 normal controls (mean age 43 +/- 5) were also considered. For each patient after an overnight fasting a withdrawal of venous blood was done within 24-36 hours after the admission. For each sample the determination of seven prothrombotic markers [(fibrinogen (F), factor VII (F VII), antithrombin III (AT III), protein C (PC), protein S (PS) (coagulometric method IL), tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1) (ELISA method Boehringer)] and of three prethrombotic markers [(fibrinopeptide A (FPA), beta-thromboglobulin (BTG) and D-dimer (D-D) (ELISA method, Boehringer)] was performed. The results obtained in the group of the cerebrovasculopathic patients compared to the controls showed a significant increase of F (p < 0.001), F VII (p < 0.005), BTG (p < 0.05) and D-D (p < 0.01), whereas significant differences regarding AT III, PC, PS, t-PA, PAI and FPA were not observed. The authors hypothesized that the increased levels of fibrinogen and factor VII in the cerebrovascular subjects, globally considered, may depend on a marked prothrombotic state, linked in a pathogenetic sense to the vascular disease; the existence of a prethrombotic state is also documented by the increase of betathromboglobulin and D-dimer.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Haemostatic balance in patients with acute focal cerebral vasculopathy. 760 35

Diabetes mellitus is associated with disturbances of the hemostatic system, which might contribute to the development of diabetic vascular disease. We investigated the effect of metabolic improvement by insulin therapy on the haemostatic system in 61 patients with type 2 diabetes mellitus and secondary sulfonylurea failure compared with 45 healthy control subjects matched for age, sex and BMI. Median age was 65, median diabetes duration 10 years. Median HbA1c (10%) and fructosamine (4.0 mM) levels were elevated before induction of therapy and decreased significantly within 6 months of insulin treatment to 7.5% and 3.0 mM, respectively (p < 0.0001). Compared with control subjects, median plasma levels of fibrinogen (317 vs 286 mg/dl), coagulation factor VII activity (1.1 vs 0.89 U/l), von Willebrand factor (1.6 vs 1.3 U/l), D-dimer (105 vs 86 micrograms/l), protein C:Ag (1.24 vs 0.95 U/l), total protein S:Ag (1.15 vs 0.91 U/l), and antithrombin III activity (1.17 vs 1.08 U/l) were significantly elevated. Levels of free protein S were not different from control values. No significant decline of coagulation parameters could be recorded during insulin therapy. Patients with diabetic vasculopathy had higher levels of D-dimer than those without (133 vs 76 micrograms/l before, 109 vs 88 micrograms/l during therapy), whereas the other haemostatic parameters were not different. Our data indicate a significant activation of the coagulation system in diabetic patients with secondary failure to sulfonylurea drugs, with signs of a prethrombotic state and endothelial cell disturbance.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Haemostatic abnormalities persist despite glycaemic improvement by insulin therapy in lean type 2 diabetic patients. 858 33

Homocystinuria is a rare inherited metabolic disease. Arterial and venous thromboembolic events represent frequent and life-threatening complications in homocystinuric patients. It has been suggested that mild homocysteinemia could be a risk factor for vascular disease. We have therefore measured total plasma homocysteine (HCy) concentrations by radioisotopic assay in 50 subjects with venous or arterial thrombosis and studied the relationship between HCy, coagulation and fibrinolytic parameters. Values were considered abnormal if they were higher than 2.7 standard deviations (SD) above the mean, i.e., 14.1 mmol/l. Thus, eighteen of the 50 patients with thrombosis were classified in the hyperhomocysteinemia group. Nine of these subjects had only this isolated risk factor. No correlations were found between HCy and antithrombin III, protein C, protein S and plasminogen levels, or plasma plasminogen activator inhibitor activity. Nevertheless, the correlation between tissue-plasminogen activator antigen and total plasma HCy was significant (r = 0.61, p < 0.001). Increased homocysteinemia seems to be a risk factor for thrombotic events especially knowing that HCy presents a direct cytotoxic effect. Vitamin therapy, already used in homozygote homocystinuric patients, might be beneficial in the prevention of thromboembolic disease in heterozygous patients.
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PMID:Elevated total plasma homocysteine, a risk factor for thrombosis. Relation to coagulation and fibrinolytic parameters. 832 83

Increased urinary albumin loss in patients with Type 1 diabetes is associated with accelerated atherosclerosis. Prothrombotic factors known to be associated with cerebrovascular and coronary artery disease in the general population, antithrombotic factors, were studied in 52 patients with Type 1 diabetes and varying urinary albumin loss and 24 non-diabetic control subjects. Fibrinogen increased from 2.5 g l-1 (95% confidence interval 2.3-2.8) in control subjects and 2.8 g l-1 (2.6-3.0) in diabetic patients without microalbuminuria to 3.1 g l-1 (2.7-3.5) with microalbuminuria (p < 0.005 vs control; p < 0.001 vs without microalbuminuria). Factor VIIc increased from 81% (75-86% in non-diabetic control subjects and 84% (78-90%) in diabetic patients without microalbuminuria to 103% (89-117%) with microalbuminuria (p < 0.005 vs control; p < 0.05 vs without microalbuminuria) and 118% (86-150%) with albuminuria (p < 0.005 vs control and p < 0.001 vs without microalbuminuria). Levels of the antithrombotic factors protein C, protein S, and antithrombin III also rose in the diabetic patients with evidence of renal damage. Elevation of prothrombotic factors has been associated with increased risk of microvascular disease, whereas elevation of antithrombotic factors has no known protective effect. Therefore, this pattern of alteration of haemostatic factors in diabetic renal disease may contribute to the increased risk of vascular disease associated with both microalbuminuria and albuminuria.
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PMID:Prothrombotic and antithrombotic factors are elevated in patients with type 1 diabetes complicated by microalbuminuria. 845 88


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