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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Formation of free radicals and subsequent lipid peroxidation may have an important role in tissue injury and neuronal cell death after cerebral ischaemia. We conducted a prospective, controlled study to determine whether the endogenous antioxidant vitamins A and E had a protective function in acute ischaemic stroke. The study population consisted of 80 patients seen at the Free University Hospital in Brussels. Entry criteria were occurrence of sudden focal neurological deficit lasting more than 3 h; deficit due to acute ischaemia in the territory of the middle cerebral artery; and investigation within 24 h of onset of the episode. Outcome was assessed within the first 21 days. 80 controls matched for age and sex had various neurological disorders other than acute ischaemia. Serum concentrations of vitamins A and E were similar in the study and control groups. In the study population a serum vitamin A concentration higher than the mean of 2.27 mumol/l was associated with a higher frequency of complete recovery within the first 24 h (p less than 0.05), decreased mortality (p = 0.038), and a better outcome as assessed by the Mathew scale of neurological deficit (p less than 0.03) and the Barthel index. There was no significant difference in outcome between patients with vitamin E concentrations above or below the mean of 35.3 mumol/l. Our results suggest a beneficial effect of a high serum vitamin A concentration on early outcome in ischaemic stroke.
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PMID:Serum concentrations of vitamins A and E and early outcome after ischaemic stroke. 135 49

There is accumulating evidence that free radicals may contribute to various diseases such as cancer or cardiovascular disease. Possible health hazards can to some extent be prevented by the body's multilevel defense system against free radicals, which comprises, besides others, antioxidant vitamins. The 12-year mortality follow-up of 2,974 participants of the Basal Study allowed to test the hypothesis that low antioxidant vitamin plasma concentrations (vitamin A, C, E and carotene) were associated with increased death from cancer of various sites and death from atherosclerosis such as ischemic heart disease and stroke, respectively. For the analysis 204 cancer cases, 132 fatalities from ischemic heart disease (IHD) and 31 deaths from cerebral vascular disease were available. Cancer mortality. Overall mortality from cancer was associated with low mean plasma levels of carotene adjusted for cholesterol (p less than 0.01) and of vitamin C (p less than 0.01). Bronchus and stomach cancers were associated with a low mean plasma carotene level (p less than 0.01). Subjects with subsequent stomach cancer had also lower mean vitamin C and lipid-adjusted vitamin A levels than survivors (p less than 0.05). Calculating the relative risk with exclusion of mortality during the first two years of follow-up, low plasma carotene was associated with an increased risk for bronchus cancer (RR 1.8, p less than 0.05), and the small number of stomach cancer cases (RR 2.95, p less than 0.05) low plasma levels of carotene and vitamin A with all cancer types (RR 2.47, p less than 0.01), and low plasma retinol in older subjects (greater than 60 years) with lung cancer (RR 2.17, p less than 0.05). Studies in other cohorts with a poor vitamin E status revealed an increased risk of subsequent cancer at low vitamin E levels as well. It is concluded that low plasma levels of all major essential antioxidants are associated with an increased risk of subsequent cancer mortality. Cardio-vascular mortality. Plasma carotene concentration below quartile 1 was associated with an increased risk for IHD (RR 1.53, p = 0.02). The same was true for low levels of both carotene and vitamin C (RR = 1.96, p = 0.022). The risk of cerebrovascular death was elevated in subjects with low carotene in the presence of low vitamin C plasma concentration (RR 4.17, p less than 0.01). These data confirm and extend recent findings on an inverse correlation of beta-carotene and vitamin C respectively to CVD.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Inverse correlation between essential antioxidants in plasma and subsequent risk to develop cancer, ischemic heart disease and stroke respectively: 12-year follow-up of the Prospective Basel Study. 145 Jun

The effectiveness of acute stage vascular reconstruction in cases of progressing stroke is reported. The clinical material consists of 28 cases of progressing stroke in the anterior circulation upon which vascular reconstruction was performed. Following admission, brain protective substances (500 ml mannitol, 500 mg vitamin E, 500 mg phenytoin) and dextran, were administered to the patients, and induced hypertension was also performed. Changes in symptoms were then observed and vascular reconstruction was carried out in cases where symptoms progressed. The vascular lesion was on the internal carotid artery in 8 cases and on the middle cerebral artery in 20 cases. Complete disappearance of neurological symptoms was obtained in 12 cases, whereas only mild neurological symptoms remained but a return to normal social life was possible in 11 other cases. Symptoms remained in three cases and there were two fatalities. In a long-term follow-up study, there were no cases of aggravation of symptoms due to ischaemic stroke. Moreover, the reconstruction was judged as effective on the basis of cerebral blood flow and metabolism. We concluded that acute vascular reconstruction for progressing stroke under the administration of brain protective substances is effective in preventing the progression of neurological symptoms.
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PMID:Acute revascularization for progressing stroke. 177 9

We examined the 21-aminosteroid U74006F, a potent inhibitor of lipid peroxidation, for potential neuroprotective effects in a canine model of complete cerebral ischemia. Two 1.5-mg/kg boluses were administered to six dogs, the first bolus 15 minutes prior to a 12-minute episode of complete cerebral ischemia and the second bolus after 11 minutes of ischemia, 1 minute prior to reperfusion. Using this dosage regimen, plasma U74006F levels of greater than 0.3 microgram/ml were maintained for up to an hour postischemia. An additional six animals received equal volumes of the citrate vehicle solution. At 24 and 48 hours postischemia, the dogs were neurologically evaluated by an observer blinded as to treatment selection. All six U74006F-treated animals had a normal neurologic outcome at 48 hours postischemia, while the citrate vehicle-treated animals all suffered moderate to severe neurologic deficits. The difference in outcome was significant at both 24 and 48 hours (p less than 0.005). Although U74006F is a 21-aminosteroid, it is not reported to possess glucocorticoid activity. This is supported by the present finding that no changes in plasma glucose concentration were observed following administration of the drug. The systemic vitamin E levels of citrate vehicle-treated animals decreased significantly (from 4.10 +/- 0.46 micrograms/ml to 2.95 +/- 0.38 micrograms/ml, p less than 0.05), whereas the vitamin E levels in U74006F-treated animals did not decrease significantly. These results suggest that U74006F may be of benefit in improving neurologic outcome when administered prior to an episode of complete cerebral ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)
Stroke 1991 Jul
PMID:Pretreatment with U74006F improves neurologic outcome following complete cerebral ischemia in dogs. 185 10

Twenty-four hour postischemic neuronal necrosis was compared in male vs. female Mongolian gerbils subjected to a 3-h period of severe incomplete hemispheric ischemia produced by unilateral carotid occlusion. The incidence of stroke-prone males was 42.9% versus 26.7% for the females. Among the stroke-prone animals, the males displayed significantly greater neuronal necrosis at 24 h after ischemia compared to the females in the cerebral cortex and CA1 region of the hippocampus. In the CA1 region of the stroke-prone males, only 2.0% of the normal neuronal population remained by 24 h compared to 36.8% in the stroke-prone females (p less than 0.02). In the cerebral cortex, the males had only 19.9% of normal versus 58.2% in the females (p less than 0.05). In a second series of mechanistic experiments, no differences in cortical blood flow (CBF) were disclosed between preselected male and female stroke-prone animals before, during, or for 2 h after ischemia. As with the CBF, the extent of cortical extracellular hypocalcia during ischemia did not differ significantly. However, the degree of postischemic recovery of cortical extracellular calcium was significantly better in the females from 30 min to 2 h after reperfusion. In the same experiments, hemispheric vitamin E levels were measured at the 2 h time point as an index of postischemic brain lipid peroxidation. No difference in baseline vitamin E levels was observed between male and female sham-operated gerbils. In the males subjected to 3 h of ischemia plus 2 h of reperfusion, the hemispheric vitamin E decreased by 43.5% compared to the sham-operated males.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sex differences in postischemic neuronal necrosis in gerbils. 199

We describe the effects of the 21-aminosteroid tirilazad mesylate (U-74006F) on postischemic lipid peroxidation (depletion of brain vitamin E) and cortical extracellular calcium recovery in gerbils subjected to 3 hours of unilateral carotid artery occlusion. Male gerbils were treated with either 0.2 ml vehicle (0.05N HCl) or 10 mg/kg i.p. U-74006F 10 minutes before the induction of ischemia and again immediately after the initiation of reperfusion. In the first series of experiments, the brain concentration of vitamin E, which was unaffected by ischemia without reperfusion, was decreased after 2 hours of reperfusion by an average of 60% in vehicle-treated animals compared with sham-operated animals; in the U-74006F-treated gerbils, the 2-hour postischemic vitamin E loss was only 27% (p less than 0.002 different from vehicle-treated animals). In the second series, unilateral carotid artery occlusion produced a decrease in the cortical extracellular calcium concentration from 1.05 mM before ischemia to 0.11 mM by the end of the ischemic episode in both vehicle- and U-74006F-treated gerbils. After 2 hours of reperfusion, the calcium concentration had recovered to only 0.22 mM in the vehicle-treated animals compared with 0.56 mM in the U-74006F-treated group (p less than 0.01). Cortical blood flow, mean arterial blood pressure, and blood gases did not differ significantly between the two treatment groups. Administration of only the immediate postreperfusion dose (i.e., no pretreatment) also significantly improved the recovery of cortical extracellular calcium. The results indicate that U-74006F inhibits postischemic lipid peroxidation as assessed by the preservation of brain vitamin E and that, secondary to this membrane-protective effect, the processes responsible for the reversal of ischemia-triggered intracellular calcium accumulation are preserved.
Stroke 1991 Mar
PMID:Effects of tirilazad mesylate on postischemic brain lipid peroxidation and recovery of extracellular calcium in gerbils. 200 6

Much of the research related to cardiopulmonary bypass in recent years has been directed toward defining the changes in plasma and blood cells during bypass. In this review, recent information is reexamined for six areas of current interest. These areas are complement activation, immune response, anaphylactic reactions, coagulation, and cerebral dysfunction. Complement may be activated by either the classical or alternate pathway during cardiopulmonary bypass and protamine administration. Membrane oxygenators appear to diminish the degree of complement activation. Complement is a major factor in the whole body inflammatory response; which often accompanies cardiopulmonary bypass. A product of complement activation, C5a- desArg, causes activation and aggregation of granulocytes. Other products of complement activation lead to lysis of blood cells including granulocytes and red cells. Bubble oxygenators appear to have a distinct disadvantage compared to membrane oxygenators regarding infection. Airborne microorganisms are more likely to be entrained into circulating blood with bubble oxygenators than with membrane oxygenators. Bubble oxygenators cause a greater decrease in leukocyte number and function than membrane oxygenators. Anaphylactic reactions have been associated with use of antibiotics, blood products, protamine, and volume expanders during cardiopulmonary bypass. Protamine reactions may be on an immunological basis or due to direct toxicity of the drug. Free radicals including superoxide, hydrogen peroxide, and the hydroxyl radical may be generated during cardiopulmonary bypass and reperfusion. Free radical scavengers including; vitamin E, coenzyme Q, vitamin C, mannitol, and glutathione have been studied. The avoidance of blood transfusion because of risk of transmitted infection including AIDS has become a major goal in cardiac surgery. Factors that correlate with increased transfusion requirement include low hematocrit, female gender, increased age, small body size, low ejection fraction, reoperation, and emergency operation. Heparin resistance due to antithrombin III deficiency is being recognized more commonly. Antithrombin III deficiency may be corrected with fresh frozen plasma. Patients with heparin induced thrombocytopenia may be difficult to manage. Several management protocols are suggested. The most straightforward appears to be the use of aspirin preoperatively and platelet transfusions postoperatively. The incidence of cerebral dysfunction after cardiopulmonary bypass depends on the sensitivity of the test or indicator used. Perioperative stroke is associated with intrinsic cerebrovascular disease and atherosclerosis of the ascending aorta. Retinal angiograms during cardiopulmonary bypass show that microemboli are very common. Cerebroplegia has been shown to extend the period of safe circulatory arrest in animals. Much of the new knowledge concerning cardiopulmonary bypass is the result of close collaboration between cardiac surgeons and nonsurgical scientists.
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PMID:Pathophysiology of cardiopulmonary bypass: current issues. 213 41

Clinicopathological studies were performed on 156 lenses of human senile cataract obtained by cataract operations between 1970 and 1988. It became clear that the aging influences the functional destruction of the equatorial region, the pathological changes of the bow area, and changes of the extralens environment. After operation for the atrophic type of the posterior subcapsular cataract, aftercataract easily develops on the intraocular lens and this requires treatment. Long-term observations were carried out in 180 Wistar male rats under the same laboratory condition and histological studies were performed. The similarities between the senile Wistar rat cataract and the human senile cataract indicate that the Wistar rat cataract is useful as a model for studying the human senile cataract. These rats were initially classified into six groups (control, vitamin E diet, EPC eye drops, catalin eye drops and reduced catalin eye drops). To study the effects of the agents (vitamin E, ARI, EPC, catalin, reduced catalin) on the cataract in senile Wistar rats the mean cell density of lens epithelia were measured at 2 or 3-month intervals. There were no statistically significant differences in treated groups and the control group. The results suggest that these agents affect another factor of lens apart from the proliferative activity of lens epithelial cell. Effects of anti-cataract agents were investigated using cultured lens epithelial cells. When cultured rat lens epithelial cells were incubated in medium containing selenite, super-oxide dismutase (SOD) activity and GSH in the cells markedly decreased, and GSSG was markedly increased. When cultured rabbit lens epithelial cells were incubated in medium contained selenite and glutathione, SOD activity was maintained normal level. When cultured lens epithelial cells were incubated in medium contained selenite and pirenoxin, SOD activity also maintained a normal level. These results suggest that both glutathione and pirenoxin are effective as anti-cataract agents. Cataracts in spontaneously hypertensive rats (SHR) was investigated on male of Wistar-Kyoto rats (WKY), stroke resistant SHR (SHRSR) and stroke-prone SHR (SHRSP) rats aged 3 to 9 months. Cataracts in these rats were classified as follows: Type 0: no opaciiy, Type 1: nuclear opacity, Type 2: posterior subcapsular opacity, Type 3: nuclear opacity associated posterior subcapsular opacity and Type 4: complete opacity in both lenses. Incidence of cataract in WKY was 2.6%, SHRSR, 76.8% ant SHRSP, 88.2%. Incidence of nuclear opacity was remarkably higher in SHRSP (48.5%). In SHR aged from 3 to 5 months, nuclear opacity was ahead of the appearance of posterior subcapsular opacity which was increased during aging.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Cataract--clinic and pathology]. 227 35

A 37-year-old man was admitted to our clinic 3 hours after the onset of cerebrovascular accident with right hemiparesis and total aphasia. On admission, we started combined administration of mannitol, vitamin E, phenytoin (Sendai Cocktail) and perfluorochemicals to protect ischemic brain. Left cerebral angiography revealed occlusion of the left middle cerebral artery involving its perforating arteries. Following the performance of angiography, vascular balloon catheter was introduced into the embolus, and fibrinolytic agent (urokinase) was continuously injected. Soon after the injection of 240,000 unit urokinase, recanalization of left middle cerebral artery was shown by repeated cerebral angiography performed 5.5 hours after the onset. On his clinical course, left hemiparesis and aphasia were improved step by step, and 1 week later, he could walk by himself with minor neurological deficits. Further examination revealed that myxoma was located on left atrium by echocardiography. Within 1 week, the patient was transferred to cardio-surgical unit, and myxoma was successfully removed. Now he is in good health and has returned to his job. Usually cerebral embolisms result from atrial myxoma cause severe cerebral infarction. Here we reported a case of cerebral embolism by myxoma and recanalized using fibrinolytic agent by balloon catheter injection. The damage will be reduced if the duration of occlusion is limited, so this method will be helpful to treat cerebral embolism.
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PMID:[A case of cerebral embolism caused by atrial myxoma--superselective fibrinolytic therapy]. 344 2

The association between low serum selenium, vitamin A, and vitamin E levels and mortality from cardiovascular disease (CVD) was investigated in a case-control study nested in a 9-yr prospective study in the Netherlands. For 10,532 persons aged greater than or equal to 5 yr who participated in a 1975-1978 medical survey, serum was stored at -20 degrees C. For the 84 of 106 subjects aged 37-87 yr who died of CVD after the baseline exam, 168 cohort members alive at the end of 1983 and matched for age and gender were selected as controls. No significant associations between serum selenium. vitamin A, vitamin E, and CVD mortality were observed before and after multivariate analyses. The adjusted risk of death from CVD for subjects in the lowest selenium quintile (less than 105.0 micrograms/L) was 1.6 (95% CI, 0.8-3.2). For coronary and stroke death risk, estimates were 1.1 (95% CI, 0.5-2.6) and 3.2 (95% CI, 0.8-12.1). Our findings do not show a clear CVD risk from low selenium and vitamin levels. Although some of the risk estimates were strong, larger studies are required for definitive conclusions.
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PMID:Serum selenium, vitamin antioxidants, and cardiovascular mortality: a 9-year follow-up study in the Netherlands. 381 45


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