William Powers

..Three randomized trials of intra-arterial thrombolysis (IAT) for acute ischemic stroke ≤ 6 hours were conducted without intravenous tissue plasminogen activator (IV-tPA) treatment of patients in the control groups now known to benefit...

..This article will discuss the design, analysis, and interpretation of clinical research studies carried out to establish the accuracy and clinical value of neuroimaging to select such patients...

..Data from human participants have failed to resolve the question whether cerebral blood flow (CBF) in the peri-infarct region will decrease due to impaired autoregulation when systemic mean arterial pressure (MAP) is rapidly reduced...

..Which is the case in early PD and whether these metabolic abnormalities are important in the pathogenesis of PD will require further study...

..Recent data demonstrating contralateral hemispheric damage in patients with acute ICH provide further support for this theory of common injury mechanisms...

..On the basis of these data, we conclude that measures of mitochondrial complex I and I+III activity in platelets within the ranges we have studied do not correlate with oxidative function of cerebral mitochondria...

..Our findings provide evidence for compartmentalization of brain metabolism into a basal component in which CBF is coupled to oxygen metabolism and an activation component in which CBF is controlled by another mechanism...

..Asymptomatic carotid occlusion has a benign prognosis and requires no specific treatment other than lifestyle modification and risk factor intervention...

..Patients with symptomatic atherosclerotic internal carotid artery occlusion (AICAO) and hemodynamic cerebral ischemia are at high risk for subsequent stroke when treated medically...

..Whether this is the case in early PD and whether it is important in the pathogenesis of PD will require further study...

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..Whether the role of PET expands to impact the management of individual patients will depend on the results of investigations like the Carotid Occlusion Surgery Study that directly assess the ability of PET to influence patient outcome...

..CONCLUSIONS: In euvolemic patients with vasospasm, intravascular volume expansion with a normal saline bolus raised CBF in regions of the brain most vulnerable to ischemia...

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..Because glycolytic metabolism is predominantly astrocytic, the selective reduction in striatal CMRglc raises the possibility that astrocyte dysfunction may be involved in the pathogenesis of HD...

..In the present study they sought to determine if hyperventilation lowers CBF below the ischemic threshold of 18 to 20 ml/100 g/ min in any brain region and if those reductions cause energy failure (defined as a fall in CMRO2)...

..30, 95% CI=-7.7 to 2.7). The absence of significant change in CBF with a 10 to 15 mm Hg reduction in MAP within the normal autoregulatory range demonstrates that there is neither a generalized nor local defect of autoregulation in AD...

..9+/-13.5 and 44.2+/-13.3 mL/100 g min for the statin and nonstatin groups, respectively. We conclude that the stroke risk reduction observed with statin therapy in humans likely involves mechanisms other than an increased basal CBF...

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..Reductions > 10% were excluded with 80% confidence. A systemic defect in complex I activity is not present in early HD when striatal neuronal degeneration is already present...

..It is estimated that 186 patients will be required in each group. Assuming that 40% of PET scans will demonstrate increased OEF, this will require enrolling 930 clinically eligible individuals...

..We investigated the role of cerebral mechanisms in HAAF by measuring regional brain activation during recurrent hypoglycemia with attenuated counterregulatory responses and comparing it with initial hypoglycemia in healthy individuals...

..The physiological explanation for the measurement of normal CBV in patients with increased OEF is less certain and may reflect preserved autoregulatory capacity...

..The purpose of this study was to investigate the clinical and imaging features of stroke in these patients...

..If such studies yield consistent results, they will establish the basis for the utilization of platelet rnitochondrial function assays to monitor cerebral mitochondrial metabolism. ..

..Through the use of the unique resources and personnel at Washington University Medical Center, we have the opportunity to provide answers to important clinical and mechanistic questions in AD. ..