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

In view of the known association of vascular disease with increasing age, we have conducted an analysis of hemostatic system activity with respect to perturbations induced by aging phenomena. We have utilized an immunochemical assay for prothrombin fragment F1 + 2 to quantify Factor Xa activity upon prothrombin in the plasma of 199 healthy males between the ages of 42 and 80. The levels of F1 + 2 in this population generally increased as a function of age (P less than 0.0001). The metabolic behavior of this marker was determined in 10 individuals greater than 65 yr of age with varying levels of F1 + 2, which ranged from 1.28 to 5.85 nM. The elevations in the concentration of this component were not due to diminished clearance of the fragment. Radio-immunoassays for fibrinopeptide A (FPA) and the protein C activation peptide (PCP) were subsequently employed to measure thrombin activity upon fibrinogen and thrombin-thrombomodulin activity upon protein C, respectively, in 82 members of this population ranging in age from 42 to 80. Significant positive correlations were again observed between increasing age and the level of F1 + 2 (P less than 0.0001) as well as FPA (P less than 0.01) and PCP (P less than 0.002). The results of this cross-sectional study indicate that many apparently normal males of increasing age with normal immunologic levels of antithrombin III and protein C exhibit a biochemical defect that denotes the presence of an acquired prethrombotic state.
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PMID:Aging-associated changes in indices of thrombin generation and protein C activation in humans. Normative Aging Study. 282 64

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

To study a possible hypercoagulability in vascular disease, in 22 patients with essential hypertension and in 13 patients with obliterative arteriopathies of the lower limbs we measured the levels of plasma thrombomodulin (TM), plasma and urine beta-thromboglobulin (beta-TG), plasma D-dimer (DD) and plasminogen activator-inhibitor (PAI-1) and compared to the values obtained from 10 healthy volunteers. The values observed in hypertensive patients show only PAI-1 levels significantly higher. All the parameters were found to be significantly increased in vasculopathic patients. These data confirm that in vasculopathic patients endothelium damage, platelet activation, impaired fibrinolytic potential and increase of fibrin turnover, occur. On the other hand, in the hypertensive patients, at first stages of the disease, we have found only an increase of PAI-1 plasma levels documenting impaired fibrinolytic potential.
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PMID:Hemostatic disorders associated with arterial hypertension and peripheral arterial disease. 852 67

The effect of the short-term administration of beraprost sodium, an analogue of prostaglandin I2 (PGI2), on the function of vascular endothelial cells and platelet in non-insulin-dependent diabetes mellitus (NIDDM) patients was investigated. Seven nonobese NIDDM patients with microalbuminuria were recruited for this study. They received a dose of 20 micrograms of beraprost sodium three times daily for 1 month. Before and after this treatment, various factors concerning functions of vascular endothelial cells and platelet were measured. Treatment with PGI2 analogue caused a decrease in basal levels of plasma lipoprotein (a) from 16.8 +/- 5.3 to 13.2 +/- 4.4 mg/dL (p < 0.05), immunoreactive-(i)endothelin from 2.4 +/- 0.3 to 1.6 +/- 0.2 pg/mL, and i-thrombomudulin from 9.3 +/- 3.7 to 7.9 +/- 3.0 FU/L, respectively, and caused a significant increase in basal plasma i-tissue type plasminogen activator (tPA) from 5.3 +/- 0.7 to 8.3 +/- 1.5 ng/mL (p < 0.01). This treatment also increased maximum response of i-tPA induced by desmopressin infusion. Platelet aggregation due to ADP was inhibited in five of six patients after this treatment. In conclusion, treatment with PGI2 analogue caused a decrease in the presumed promoting factors of angiopathy such as lipoprotein (a) and endothelin and an increase in the protecting endothelial factor of angiopathy, tissue type plasminogen activator in patients with NIDDM. And immunoreactive thrombomodulin levels which reflect the vascular endothelial cell injury tended to decrease with the treatment. Therefore, it is suggested that this treatment preserves the vascular endothelial function in diabetes.
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PMID:The effect of PGI2 analogue on vascular endothelial function and platelet aggregation in patients with NIDDM. 857 59

The case of a 75-year-old Japanese woman with adult-onset Still's disease who presented with cerebral haemorrhage is described. She had been in clinical remission for 2 years, after induction therapy including non-steroidal anti-inflammatory drugs, prednisolone, cyclophosphamide and mizoribine followed by auranofin, until her cerebral haemorrhage occurred, although her serum level of ferritin had gradually increased. After the onset of cerebral haemorrhage, the patient's serum level of thrombomodulin was elevated although c-reactive protein and lactate dehydrogenase were not increased. Anti-cardiolipin antibody and lupus anti-coagulant were not detected. Patients with adult-onset Still's disease are rarely reported to develop cerebral vascular disease, possibly because the disease is most frequent in young adults. The cerebral haemorrhage may have been caused by the vasculitis due to Still's disease.
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PMID:Cerebral haemorrhage complicating adult-onset Still's disease: a case report. 895 35

Recently, we found an increase in tissue factor pathway inhibitor (TFPI) activity in patients with insulin-dependent diabetes mellitus (IDDM). This increase in TFPI activity could be the result of increased thrombin formation and/or altered binding of TFPI to glycosaminoglycans. We studied TFPI activity (chromogenic assay) in relation to prothrombin F1 + 2 fragments and endogenous thrombin potential (ETP), in 46 IDDM patients, and 18 age and sex-matched healthy controls. Prothrombin, antithrombin and thrombomodulin were also determined. In IDDM patients, TFPI activity and F1 + 2 levels were significantly higher, while ETP, prothrombin antigen levels, and antithrombin activity were lower as compared to the controls. In IDDM patients with microalbuminuria, a manifestation of generalized angiopathy, TFPI activity, F1 + 2 and thrombomodulin levels were higher than in patients with only retinopathy or patients without complications. No correlation between TFPI activity, F1 + 2 levels and thrombomodulin was found, while TFPI activity was negatively correlated with ETP (r = -0.27). Microalbuminuria was significantly correlated with TFPI activity (r = 0.46), F1 + 2 (r = 0.56), and thrombomodulin (r = 0.52). In TFPI-depleted plasma, ETP increased, indicating that ETP is affected by TFPI. In conclusion, the increase in TFPI activity in IDDM patients may not be considered to be a reaction on a procoagulant state. It is hypothesized that vascular damage, leading to alterations in glycosaminoglycans, is in part responsible for the changes in TFPI activity, F1 + 2 levels and ETP.
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PMID:Increased tissue factor pathway inhibitor (TFPI) and coagulation in patients with insulin-dependent diabetes mellitus. 906 96

Secondary prevention of atherosclerosis, especially before the onset of symptoms, appears desirable and could be possible with a serum marker detecting atherosclerosis. Circulating, shedded forms of adhesion molecules may serve as such because their expression is upregulated in atherosclerotic plaques. In 52 patients with peripheral arterial vascular disease (Fontaine class IIa, 7 patients; class IIb, 29 patients; and class III, 16 patients), the extent of atherosclerosis was evaluated on the basis of angiograms of a large portion of the arterial system. The area diseased by atherosclerosis was determined by the percentage of vessel wall irregularities of the following calculated segments: aorta (distal from the kidney arteries), common iliac artery, external iliac artery, common femoral artery, lateral circumflex femoral artery, and popliteal artery. The maximal surface area that could exhibit atherosclerotic changes was 250 cm2. The serum concentration of circulating vascular cell adhesion molecule-1 (VCAM-1) correlated with the extent of atherosclerosis (r = .8, P < .001). In contrast, circulating intercellular adhesion molecule-1, E-selectin, P-selectin, and thrombomodulin (as markers for endothelial cell damage) did not correlate with the extent of atherosclerosis. Furthermore, circulating VCAM-1 could be used to indicate stages of atherosclerosis with a high degree of statistical significance. The potential bias of factors such as age, diabetes mellitus, hypercholesterolemia, arterial hypertension, renal failure, and history of myocardial infarction on the correlation of circulating VCAM-1 with the extent of atherosclerosis could be excluded by multivariate analysis. These findings suggest an important role of VCAM-1 in atherosclerosis and may serve as the basis for further evaluation of circulating VCAM-1 as a potential serum marker for atherosclerosis.
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PMID:Circulating vascular cell adhesion molecule-1 correlates with the extent of human atherosclerosis in contrast to circulating intercellular adhesion molecule-1, E-selectin, P-selectin, and thrombomodulin. 910 69

The role of reduced endothelial production of EDRF-NO in the pathogenesis of diabetic angiopathy has received much attention, however, most of the rather conflicting data were gained from animal experiments. Limited human experience seems to be available in insulin dependent diabetes, calling attention to decreased EDRF-NO production. Hereby the clinical, as well as laboratory investigation (urinary and serum nitrate/nitrite, lipid peroxidation, glucometabolic parameters, endothelial and in vivo platelet activation markers, etc.) of 35 non-insulin dependent (NIDDM) and 15 insulin dependent diabetics (IDDM) patients are given. Urinary and serum nitrate/nitrite concentrations were proven to be reduced in both patients groups. This change was independent of diabetes duration, presence of macroangiopathy, coronary heart disease and the glucometabolic parameters, however, correlation was registered with lipid peroxidation (total antioxidant status). An inverse correlation of nitrate/nitrite excretion with endothelial markers (von Willebrand factor, soluble thrombomodulin) was documented in NIDDM, this correlation was much stronger in IDDM. Moreover, in IDDM patients reduced nitrate/nitrite excretion was strongly associated with elevated plasmatic beta-thromboglobulin levels. The data presented here support to the hypothesis, that EDRF-NO production is reduced in diabetes and this reduction seems to correlate with endothelial damage. In IDDM the decreased nitrate/nitrite excretion may also lead to increased in vivo platelet activation, which suggests that the reduced amount of EDRF-NO might play a role in the pathogenesis of angiopathy in IDDM.
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PMID:The association of reduced endothelium derived relaxing factor-NO production with endothelial damage and increased in vivo platelet activation in patients with diabetes mellitus. 917 38


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