Functional recovery after stroke has been associated with brain plasticity; however, the exact relationship is unknown. We performed behavioral tests, functional MRI, and histology in a rat stroke model to assess the correlation between temporal changes in sensorimotor function, brain activation patterns, cerebral ischemic damage, and cerebrovascular reactivity. Unilateral stroke induced a large ipsilateral infarct and acute dysfunction of the contralateral forelimb, which significantly recovered at later stages. Forelimb impairment was accompanied by loss of stimulusinduced activation in the ipsilesional sensorimotor cortex; however, local tissue and perfusion were only moderately affected and cerebrovascular reactivity was preserved in this area. At 3 days after stroke, extensive activation-induced responses were detected in the contralesional hemisphere. After 14 days, we found reduced involvement of the contralesional hemisphere, and significant responses in the infarction periphery. Our data suggest that limb dysfunction is related to loss of brain activation in the ipsilesional sensorimotor cortex and that restoration of function is associated with biphasic recruitment of peri-and contralesional functional fields in the brain.

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Background: Prolongation of the peak and the end of T wave (Tp-e) has been reported to be associated with ventricular arrhythmias. Tp-e/QT ratio and Tp-e/QTc ratio are used as an index of ventricular arrhythmogenesis. An increased incidence of ventricular arrhythmias has been reported in patients with obstructive sleep apnea (OSA). The aim of this study was to assess ventricular repolarization in patients with OSA by using Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio.Methods: We have studied 72 patients who underwent overnight polysomnography (PSG) between the years 2010-2011 at our institution. Patients with moderate and severe OSA (23 patients; mean age: 45 ± 10), according to the apnea-hypopnea index, constituted the study group. Patients with normal PSG (23 patients; mean age: 42 ± 11) were used as the control group. In all patients, Tp-e interval, Tp-e/QT ratio, Tp-e/QTc ratio, as well as some other electrocardiogram intervals were measured. Independent samples t-tests were used for comparison of continuous and categorical variables and correlations were calculated by Spearman rank correlation.Results: Although QT and QTc intervals were not different between the groups, mean Tp-e interval (81.6 ± 11.1 msn; 63.9 ± 7.3 msn; respectively; P < 0.001), Tp-e/QT ratio (0.21 ± 0.03; 0.17 ± 0.02; respectively; P < 0.001), and Tp-e/QTc ratio (0.20 ± 0.03; 0.16 ± 0.02; respectively; P < 0.001) were prolonged in the study group compared to the control group. Correlation analysis showed a significant positive correlation between the presence of moderate and severe OSA and Tp-e interval (r = 0.72; P < 0.001), Tpe/QT ratio (r = 0.70; P < 0.001), and Tp-e/QTc ratio (r = 0.70; P < 0.001). Conclusions:Address for reprints: Alptug Tokatli, M.D., GATA Haydarpasa Egitim Hastanesi, Kardiyoloji servisi, Uskudar-34668; Istanbul, Turkey. Fax: 90 0 212 296 75 12;

The results of our study reveal that FMS affects quality of life and dysfunction in cognitive abilities can be determined by brain event-related potentials.