Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0917798 (cerebral ischemia)
 17,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was designed to evaluate the clinical value of consecutive measurements of the levels of the anticoagulation factors protein C. protein S and antithrombin III in the plasma of patients with subarachnoid haemorrhage (SAH). Sequential samples of plasma were obtained from 34 patients at days 0 to 3, 5, 8, 14, and 20 days after SAH. Their levels of protein C, protein S and antithrombin III were measured by specific immuno-assays, and the symptomatic vasospasm and clinical states of the patients were monitored. Based on the retrospective comparisons between the measured levels of the three factors and the levels in pooled plasma from normal volunteers, the time course of changes in the levels allowed the classification of the patients into five groups as follows: A, the levels of the three factors decreased suddenly at 5 days after SAH, then increased again (n = 6); B, the three factors increased continuously (n = 13); C, the three factors remained below the normal range (n = 3); D, the three factors remained within the normal range (n = 6); and E, the three factors decreased continuously (n = 6). In group A patients, temporary deficiencies in the three factors occurred that coincided with the occurrence of delayed neurological deficit (DND). Twelve patients (92%) in group B had a favourable outcome (good and moderate disability) without DND. The patients in group C had low levels of anticoagulation factors and mild DND followed by a favourable outcome. Five patients (83%) in group D had a favourable outcome. In group E, five patients (83%) had a poor outcome (severe disability and death) due to DND. When clinical outcomes were compared by patient group, the patients in group E had significantly more unfavourable outcomes than did the other groups (P < 0.01). Although the mechanism responsible for the decrease in anticoagulation factor levels remained unclear, the results suggested that the decrease in anticoagulation factors may indicate hypercoagulability and cerebral ischaemia after SAH.
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PMID:Plasma levels of protein C, protein S, and antithrombin III in patients with subarachnoid haemorrhage. 908 71

We analysed the results of coagulation studies in an unselected series of young adults with acute cerebral ischaemia. Our aims were (a) to determine the prevalence of coagulation disorders among these patients, (b) to investigate the relation between the presence of coagulation abnormalities and large vessel disease or potential sources of cardiac embolism and (c) to evaluate the occurrence of thrombotic events in patients with or without coagulation disorders. One hundred and twenty consecutively admitted patients (53 men, 67 women, median age 38 years, range 15-45) who presented with acute cerebral infarction (n = 89) or a transient ischaemic attack (n = 31) were evaluated. Diagnostic studies consisted of electrocardiography, echocardiography, duplex scanning, and/or angiography. Coagulation studies included activity tests of protein S, protein C, antithrombin, plasminogen, measurement of immunoglobulin G (IgG) anticardiolipin antibodies (ACLA), and a dilute prothrombin assay. Initially, 30 patients had increased ACLA titres and 28 had an abnormal dilute prothrombin assay, suggesting lupus anticoagulant. Decreased protein S, protein C and antithrombin activity were detected in 20, 3 and 3 patients, respectively, excluding patients in whom the abnormalities could be explained by the use of medication, by pregnancy or puerperium. We detected a decreased activity of plasminogen in 5 patients. The disorders could be confirmed by a second assessment in only 2 patients with a protein S deficiency, in none of the patients with a protein C or antithrombin deficiency and in 1 patient with plasminogen deficiency. However, the abnormalities persisted in 19 of 21 patients with increased anticardiolipin IgG titres and in 9 of 20 patients with lupus anticoagulant. A confirmed coagulation disorder was not associated with stroke type or vascular risk factors, but it was more common among patients with large vessel disease (odds ratio: 3.8, 95% confidence interval (CI): 1.1-12.8). Sixteen patients had a recurrent thromboembolic event, but the risk of recurrence was not increased among patients with a confirmed coagulation disorder. Our results suggest that idiopathic coagulation disorders are found in about a quarter of young stroke patients. They are difficult to predict and probably interact with other risk factors.
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PMID:Coagulation disorders in young adults with acute cerebral ischaemia. 945 24

A possible association between anticardiolipin antibodies (ACA), which are a marker for increased risk of cerebral ischemia, and deficiency of free Protein S, a naturally occurring anticoagulant, has been suspected in some studies of ischemic stroke, particularly in young adults. In order to investigate this further, we prospectively studied all stroke patients </= 65 years of age admitted to our stroke unit during 1991-1992. A total of 66 patients with acute ischemic stroke or transient ischemic attacks (TIA) (embolic/thrombotic infarction n = 30, embolic infarction n = 13, thrombotic infarction n = 10, and TIA n = 13) were analysed for ACA, protein C and S, free protein S and antithrombin III (AT III). Traditional risk factors were scrutinized in each patient. Eight patients had some previously undetected derangement of the coagulation process; five had elevated ACA levels, four had low, free Protein S levels, and three had low AT III levels. None of the patients showed any decrease in total protein C or S levels. A striking association between the presence of ACA and free protein S deficiency was noted. All patients with free protein S deficiency had concomitant elevated ACA levels. Sixteen patients had had a previous episode of ischemic stroke/TIA or mycocardial infarction, two of them had lowered AT III levels. Thirty-four patients had one or more elevated infectious parameters but with no clear correlation to derangement of the coagulation factors. We conclude that a probable association between ACA and free protein S deficiency exist in ischemic stroke patients, and that it may have a pathogenetic importance. Copyright 1998 Lippincott Williams & Wilkins
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PMID:Association between deficiency of free protein S and anticardiolipin antibodies in patients </= 65 years of age with acute ischemic stroke and TIA. 1021 Aug 79

A diagnosis of moyamoya disease was made in three children aged five, eight and 13 years (including two Turkish sisters). Clinical presentation was recurrent episodes of cerebral ischemia and stroke. CT scans and MRI showed infarcts in various distributions. Angiography revealed anterior bilateral stenosis of the circle of Willis and development of Moyamoya collateral pathways. In one case there was coagulopathy with protein C deficiency. To increase transdural collateral flow, revascularisation with encephalo-duro-arterio-synangiosis was attempted in all three children. Outcome was clinically and angiographically satisfactory and none of the children developed further neurological complications. The current state of study on Moyamoya disease is also presented.
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PMID:[Moyamoya disease: advantage of early diagnosis and survival treatment. Review of three cases]. 1058 42

Inflammatory reactions mediated by cytokines are involved in the pathogenesis of acute stroke. Decrease in circulating levels of protein C (PC) and protein S (PS) induced by inflammatory cytokines has been postulated as a potential mechanism for a procoagulant tendency during acute stroke. The procoagulant state associated with impairments in natural anticoagulants may induce microvascular obstruction leading to a tissue perfusion reduction that worsens cerebral ischemia. Interleukin-6 (IL-6) regulate the synthesis of C4b-binding protein (C4BP), an acute-phase protein that also regulates PS plasma levels. We measured IL-6, C4BP, erythrocyte sedimentation rate (ESR), total and free PS and PC in 44 patients with acute ischemic stroke to determine if IL-6 decreases circulating levels of natural anticoagulants through the C4BP pathway and if these acute changes in natural anticoagulants may have clinical implications. Patients with higher levels of IL-6 had more severe neurologic deficits on admission, greater infarct size, higher levels of acute-phase reactants, and lower levels of free PS. IL-6 was significantly correlated with C4BP, ESR, and free PS levels. PC levels were also lower in the group of patients with greater IL-6, but differences were not statistically significant. No correlations were found between C4BP and natural anticoagulants. Severe neurologic deficit, greater infarct volume, atrial fibrillation, increased levels of inflammatory parameters (ESR and IL-6), and reduced levels of free PS were associated with disabling stroke at 3 months, but only neurologic severity and ESR remained as independent predictors of stroke disability on multiple regression analysis. Inflammatory reactions mediated by IL-6 during the acute phase of stroke influence the modulation of free PS. However, variations in free PS levels do not have implications for clinical outcome in stroke patients. The link between proinflammatory cytokines and free PS in the acute phase of stroke is not related to the C4BP pathway.
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PMID:Interaction between interleukin-6 and the natural anticoagulant system in acute stroke. 1076 81

Hemostasis factors may influence the pathophysiology of stroke. The role of brain hemostasis in ischemic hypertensive brain injury is not known. We studied ischemic injury in spontaneously hypertensive rats in relation to cerebrovascular fibrin deposition and activity of different hemostasis factors in brain microcirculation. In spontaneously hypertensive rats subjected to transient middle cerebral artery occlusion versus normotensive Wistar-Kyoto (W-K) rats, infarct and edema volumes were increased by 6.1-fold (P < 0.001) and 5.8-fold (P < 0.001), respectively, the cerebral blood flow (CBF) reduced during middle cerebral artery occlusion (MCAO) by 55% (P < 0.01), motor neurologic score increased by 6.9-fold (P < 0.01), and cerebrovascular fibrin deposition increased by 6.8-fold (P < 0.01). Under basal conditions, brain capillary protein C activation and tissue plasminogen activator activity were reduced in spontaneously hypertensive rats compared with Wistar-Kyoto rats by 11.8-fold (P < 0.001) and 5.1-fold (P < 0.001), respectively, and the plasminogen activator inhibitor-1 antigen and tissue factor activity were increased by 154-fold (P < 0.00001) and 74% (P < 0.01), respectively. We suggest that hypertension reduces antithrombotic mechanisms in brain microcirculation, which may enhance cerebrovascular fibrin deposition and microvascular obstructions during transient focal cerebral ischemia, which results in greater neuronal injury.
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PMID:Brain injury and cerebrovascular fibrin deposition correlate with reduced antithrombotic brain capillary functions in a hypertensive stroke model. 1089 83

Disturbances of coagulation and fibrinolytic pathways were studied in 53 young patients with cerebral ischemia. Upon admission 26 of 53 patients had abnormality in at least one of the antithrombin-III, protein C, protein S activities or in activated protein C (APC) ratios. Three months after the first examination the majority of the previously detected abnormalities returned to normal values and the most frequent alterations were decrease in protein S activity (3 patients) and APC resistance (3 patients). Conditions resulting in impaired fibrinolysis were frequently detected upon admission. Elevation of plasminogen activator inhibitor-1, lipoprotein (a), and alpha-2-antiplasmin was present in 23, 10, and 4 cases, respectively. It is concluded that abnormalities of coagulation as well as of the fibrinolytic systems are prevalent in the acute phase of cerebral ischemia, however, the results may be significantly influenced by the disease process or the acute phase effect.
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PMID:Natural coagulation inhibitor proteins in young patients with cerebral ischemia. 1172 Oct 97

Mutations such as factor V Leiden G1691A (FVL), prothrombin G20210A (FIIM), methylenetetrahydrofolate reductase (MTHFR) C677T, cystathionine beta-synthase (CBS) 844ins68 and endothelial cell protein C receptor (EPCR) 4031ins23 are risk factors for thromboembolism. To assess the role of these mutations in young adults with cerebral ischemia of otherwise undetermined etiology, 93 patients younger than 50 years old with thromboembolic strokes or transient ischemic attacks were studied. One hundred and eighty-six healthy age-matched and sex-matched blood donors served as controls. The FVL mutation was detected in 15/93 patients and 13/186 controls. After adjustment for smoking, arterial hypertension, and hyperlipidemia, the association of the FVL mutation with cerebral ischemia [odds ratio (OR), 3.19; 95% confidence interval (CI), 1.38-7.39] remained significant. One of 93 patients and 6/186 controls were carriers of FIIM (OR, 0.33; 95% CI, 0.04-2.75). We detected the MTHFR TT677 genotype in 9/93 patients and 26/186 controls (OR, 0.66; 95% CI, 0.30-1.47), a CBS 844ins68 mutation in 12/93 patients and 19/186 controls (OR, 1.30; 95% CI, 0.60-2.81), and an EPCR 4031ins23 mutation in 1/93 patients and in no control individual (P = 0.33). In conclusion, in younger adults the FVL mutation is a risk factor for cerebrovascular disease. FIIM, the MTHFR TT677 genotype and the CBS 844ins68 mutation did not contribute to the risk in this group of patients. The EPCR 4031ins23 mutation is very rare, its possible role needs further investigation.
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PMID:Genetic risk factors in young adults with 'cryptogenic' ischemic cerebrovascular disease. 1243 43

Anti-beta -glycoprotein I antibody (abetaGPI) has been recognized in raising the risk of cerebral ischemia in patients with antiphospholipid antibody syndrome (APS), especially by protein C (PC) axis perturbation. Although a high potential is also seen in non-APS patients, the mechanism is substantially unknown. In the present study, we examined the effect of abetaGPI on PC and antithrombin-III (AT-III) activity in non-APS patients with non-cardiac cerebral ischemia (NCCI). A total of 111 NCCI patients and 30 healthy controls were enrolled. They were free of APS manifestation, and their anticardiolipin antibody and lupus anticoagulant tests were within normal range. There were 14.4% patients found to have an abnormal increase of blood abetaGPI. The PC, AT-III, albumin, aminotransferases, creatinine, prothrombin time and activated partial thromboplastin time did not differ between our patients and controls, or patients with or without increased abetaGPI. However, a marked decrease of the PC/AT-III ratio was found in patients with increased abetaGPI. The correlation between PC and AT-III activity was highly significant in patients with an increase of abetaGPI (P = 0.001), only marginal in controls (P = 0.042), and was insignificant in patients with a normal abetaGPI (P = 0.277). The abetaGPI did not correlate to PC or AT-III activity in either patients or controls. These findings suggest that high PC/AT-III coupling may relate to NCCI in non-APS patients associated with an increase of abetaGPI. This coupling effect seems not to be caused by abetaGPI directly.
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PMID:A perturbation of antithrombin-III and protein C coupling associates with an increase of anti-beta2-glycoprotein I antibody in non-antiphospholipid antibody syndrome cerebral ischemia. 1244 9

The aim of this study was to investigate the therapeutic effect of platonin, a cyanine photosensitizing dye as well as an inhibitor of proinflammatory cytokines, in an animal model of heat stroke. Anesthetized rats, immediately after the onset of heat stroke, were divided into two major groups and given the following: normal saline (1 mL per kg body weight) intravenously, or platonin (12.5-50 microg/mL per kg body weight) intravenously. They were exposed to ambient temperature of 43 degrees C to induce heat stroke. Another group of rats was exposed to room temperature (26 degrees C) and used as normothermic controls. Their physiologic and biochemical parameters were continuously monitored. When the vehicle-treated rats underwent heat exposure, their survival time values were found to be 18 to 22 min. Resuscitation with intravenous doses of platonin, but not normal saline, immediately at the onset of heat stroke, significantly improved survival during heat stroke (41-147 min). All heat-stressed animals displayed systemic inflammation and activated coagulation, evidenced by increased tumor necrosis factor-alpha, prothrombin time, activated partial thromboplastin time, fibrinogen degradation products, and D-dimer, and decreased platelet count and protein C. Biochemical markers evidenced cellular ischemia and injury/dysfunction: plasma levels of blood urea nitrogen, creatinine, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and alkaline phosphatase, and striatal levels of partial pressure of oxygen, local cerebral blood flow, glycerol, glutamate, and lactate/pyruvate were all elevated during heat stroke. The systemic inflammation, hypercoagulable state, and cerebral ischemia and injury during heat stroke were all significantly suppressed by platonin. The data demonstrate that platonin therapy may resuscitate heat stroke victims by reducing circulatory shock, systemic inflammation, hypercoagulable state, and tissue ischemia and injury.
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PMID:Platonin, a cyanine photosensitizing dye, causes attenuation of circulatory shock, hypercoagulable state, and tissue ischemia during heat stroke. 1631 90


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