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Motor Recovery (motor + recovery)
Selected AbstractsHippocampal vulnerability following traumatic brain injury: a potential role for neurotrophin-4/5 in pyramidal cell neuroprotectionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2006N. C. Royo Abstract Traumatic brain injury (TBI) causes selective hippocampal cell death, which is believed to be associated with cognitive impairment observed both in clinical and experimental settings. Although neurotrophin administration has been tested as a strategy to prevent cell death following TBI, the potential neuroprotective role of neurotrophin-4/5 (NT-4/5) in TBI remains unknown. We hypothesized that NT-4/5 would offer neuroprotection for selectively vulnerable hippocampal neurons following TBI. Measurements of NT-4/5 in rats subjected to lateral fluid percussion (LFP) TBI revealed two,threefold increases in the injured cortex and hippocampus in the acute period (1,3 days) following brain injury. Subsequently, the response of NT-4/5 knockout (NT-4/5,/,) mice to controlled-cortical impact TBI was investigated. NT-4/5,/, mice were more susceptible to selective pyramidal cell loss in Ahmon's corn (CA) subfields of the hippocampus following TBI, and showed impaired motor recovery when compared with their brain-injured wild-type controls (NT-4/5wt). Additionally, we show that acute, prolonged administration of recombinant NT-4/5 (5 µg/kg/day) prevented up to 50% of the hippocampal CA pyramidal cell death following LFP TBI in rats. These results suggest that post-traumatic increases in endogenous NT-4/5 may be part of an adaptive neuroprotective response in the injured brain, and that administration of this neurotrophic factor may be useful as a therapeutic strategy following TBI. [source] Microstructural status of ipsilesional and contralesional corticospinal tract correlates with motor skill in chronic stroke patientsHUMAN BRAIN MAPPING, Issue 11 2009Judith D. Schaechter Abstract Greater loss in structural integrity of the ipsilesional corticospinal tract (CST) is associated with poorer motor outcome in patients with hemiparetic stroke. Animal models of stroke have demonstrated that structural remodeling of white matter in the ipsilesional and contralesional hemispheres is associated with improved motor recovery. Accordingly, motor recovery in patients with stroke may relate to the relative strength of CST degeneration and remodeling. This study examined the relationship between microstructural status of brain white matter tracts, indexed by the fractional anisotropy (FA) metric derived from diffusion tensor imaging (DTI) data, and motor skill of the stroke-affected hand in patients with chronic stroke. Voxelwise analysis revealed that motor skill significantly and positively correlated with FA of the ipsilesional and contralesional CST in the patients. Additional voxelwise analyses showed that patients with poorer motor skill had reduced FA of bilateral CST compared to normal control subjects, whereas patients with better motor skill had elevated FA of bilateral CST compared to controls. These findings were confirmed using a DTI-tractography method applied to the CST in both hemispheres. The results of this study suggest that the level of motor skill recovery achieved in patients with hemiparetic stroke relates to microstructural status of the CST in both the ipsilesional and contralesional hemispheres, which may reflect the net effect of degeneration and remodeling of bilateral CST. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [source] Changes of elbow kinematics and kinetics during 1 year after strokeMUSCLE AND NERVE, Issue 3 2008Mehdi M. Mirbagheri PhD Abstract A precise description of the natural history of motor recovery after stroke provides a framework for understanding the mechanisms underlying this improvement and for tracking the efficacy of rehabilitation treatments. To characterize the time course of this change in motor impairment, we examined voluntary elbow movements in hemiparetic stroke survivors over a period of 1 year after stroke. Based on the possibility that both central nervous system and muscle factors could contribute to the observed clinical state, we hypothesized that we should observe at least two major recovery patterns of motor impairment. To explore these predictions, we assessed elbow movement range, movement speed, and isometric force generation. Subjects were examined five times over the 12-month period. We used the "growth mixture" model to characterize recovery of these measures, and the Fugl-Meyer scale (FMS) of upper-extremity function at 1 month to predict the recovery. We observed two distinct recovery classes. Class 1 started with low values for the physiological measures, and these increased over time, whereas class 2 tended to start with higher values and showed widely divergent recovery patterns. Using the logistic regression model, the impact of FMS on class membership was estimated for each parameter. Based on these data, we were able to accurately predict arm impairment recovery at different time-points in the first year, information of great potential value for planning targeted therapeutic interventions. Muscle Nerve, 2008 [source] Predicting motor recovery of the upper limb after stroke rehabilitation: value of a clinical examinationPHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 1 2000Hilde Feys Abstract Background and Purpose Only a few studies have been conducted to predict motor recovery of the arm after stroke. The aims of this study were to identify which clinical variables, assessed at different points in time, were predictive of motor recovery, and to construct useful regression equations. Method One hundred consecutive stroke patients who had an obvious motor deficit of the upper limb were evaluated on entry to the study (two to five weeks post-stroke) and at two, six and 12 months after stroke. The Brunnström,Fugl-Meyer test was used as the outcome measure. Predictors included demographic data, overall disability, clinical neurological features, neuropsychological factors and secondary shoulder complications. Results In multiple regression analyses, motor performance was invariably retained as the predictive factor with the highest R-square. Other significant predictive variables were overall disability, muscle tone, proprioception and hemi-inattention. Between 53% and 89% of the total amount of variance was accounted for in all selected models. The accuracy of prediction from clinical measurement in the acute phase diminished as the time span of measurement of outcome increased. Similarly, assessment of the variables at two and six months, rather than in the acute stage, resulted in a considerable improvement in the percentage variance explained at 12 months. The highest accuracy was obtained when predictions were made step-by-step in time. Conclusions It is possible to predict motor recovery of the upper limb accurately through the use of a few clinical measures. Predictive equations are proposed, the use of which are practicable in both clinical practice and research. Copyright © 2000 Whurr Publishers Ltd. [source] Corticosteroid Treatment for Idiopathic Facial Nerve Paralysis: A Meta-analysis,THE LARYNGOSCOPE, Issue 3 2000Mitchell Jay Ramsey CPT Abstract Objective A meta-analysis was designed to evaluate facial recovery in patients with complete idiopathic facial nerve paralysis (IFNP) by comparing outcomes of those treated with corticosteroid therapy with outcomes of those treated with placebo or no treatment. Study Design Meta-analysis of prospective trials evaluating corticosteroid therapy for idiopathic facial nerve paralysis. Methods A protocol was followed outlining methods for trial selection, data extraction, and statistical analysis. A MEDLINE search of the English language literature was performed to identify clinical trials evaluating steroid treatment of IFNP. Three independent observers used an eight-point analysis to determine inclusion criteria. Data analysis was limited to individuals with clinically complete IFNP. The endpoints measured were clinically complete or incomplete facial motor recovery. Effect magnitude and significance were evaluated by calculating the rate difference and Fisher's Exact Test P value. Pooled analysis was performed with a random effects model. Results Forty-seven trials were identified. Of those, 27 were prospective and 20 retrospective. Three prospective trials met the inclusion criteria. Tests of heterogeneity indicate the trial with the smallest sample size (RD = ,0.19; 95% CI, ,0.58,0.20), to be an outlier. It was excluded from the final analysis. Analyses of data from the remaining two studies indicate corticosteroid treatment improves complete facial motor recovery for individuals with complete IFNP. Rate difference demonstrates a 17% (99% CI, 0.01,0.32) improvement in clinically complete recovery for the treatment group based on the random effects model. Conclusions Corticosteroid treatment provides a clinically and statistically significant improvement in recovery of function in complete IFNP. [source] Activation of metabotropic glutamate receptor 5 improves recovery after spinal cord injury in rodents,ANNALS OF NEUROLOGY, Issue 1 2009Kimberly R. Byrnes PhD Objective Activation of metabotropic glutamate receptor 5 (mGluR5) has neuroprotective properties in vitro and has been reported to limit postischemic lesion volume in vivo. Previously, mGluR5 has been identified on microglia in vitro, but the effects of mGluR5 activation on inflammation in vivo or on recovery after spinal cord injury is unknown. Methods Rats received intrathecal infusion of the selective mGluR5 agonist (RS)-2-chloro-5-hydroxyphenylglycine (CHPG) for 7 days after moderate impact spinal cord injury at T9. Complementary studies examined CHPG effects on activated spinal microglia cultures. Results Functional motor recovery was significantly increased by CHPG treatment up to 28 days after injury, with improvements in weight bearing, step taking, and coordination of stepping behavior. CHPG treatment significantly reduced lesion volume and increased white matter sparing at 28 days after injury. Administration of CHPG attenuated microglial-associated inflammatory responses in a dose-dependent fashion, including expression of ED1, Iba-1, Galectin-3, NADPH oxidase components, tumor necrosis factor-,, and inducible nitric oxide synthase. Because mGluR5 is expressed by microglial cells in the rat spinal cord, such effects may be mediated by direct action on microglial cells. mGluR5 stimulation also reduced microglial activation and decreased microglial-induced neurotoxicity in spinal cord microglia cultures; the latter effects were blocked by the selective mGluR5 antagonist MTEP. Interpretation These data demonstrate that mGluR5 activation can reduce microglial-associated inflammation, suggesting that the protective effects of mGluR5 agonists may reflect this action. Ann Neurol 2009;66:63,74 [source] Early imaging correlates of subsequent motor recovery after stroke,ANNALS OF NEUROLOGY, Issue 5 2009Randolph S. Marshall MS Objective To determine whether functional magnetic resonance imaging activation obtained in the first few days after stroke correlates with subsequent motor recovery. Methods Twenty-three patients with hemiparesis after first-time stroke were scanned at 2.0 ± 0.9 days while performing a simple motor task. We defined recovery as the change in Fugl,Meyer score from time of scan to approximately 3 months later (90 ± 8 days). We performed three different tests to assess correlations between brain activation and change in Fugl,Meyer score: (1) multivariate (most sensitive to spatially diffuse activation); (2) voxel-wise Statistical Parametric Mapping (most sensitive to focal activation), and (3) primary motor cortex region-of-interest analysis (most sensitive to average activation within this region). All tests controlled for initial stroke severity and lesion volume, as well as other established clinical variables. Results The multivariate test was significant [F (595, 4,934) = 1.93; p < 0.001]. The Statistical Parametric Mapping test detected two small clusters of focal activity located in the ipsilesional postcentral gyrus and cingulate cortex (p < 0.05, corrected). The region-of-interest test was not significant. Interpretation There is a pattern of brain activation present in the first few days after stroke, of which the postcentral gyrus and cingulate cortex are a part, that correlates with subsequent motor recovery. This result suggests that there are recovery processes engaged early after stroke that could provide a target for intervention. Ann Neurol 2009;65:596,602 [source] Indorenate Improves Motor Function in Rats with Chronic Spinal Cord InjuryBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 1 2007Guadalupe Bravo Four months after a ninth thoracic vertebrae spinal cord contusion, 29 rats were randomly allocated into two groups: saline solution and indorenate-treated animals with daily doses incremented at weekly intervals. The locomotor performance of all rats was measured by the Basso, Beattie, and Bresnahan (BBB) rating scale. The results showed that at the end of the treatment, the motor activity of indorenate group was significantly better than that presented by saline solution group. The 80% of indorenate, (against 15% of saline solution) did not show detriment on motor activity. When we analysed the motor activity of rats with basal BBB lower than 10, a significant improvement of motor recovery in indorenate-treated animals was observed. The benefits observed in locomotor function at low doses followed by increasing doses could be associated with pharmacological treatment by indorenate, a well-known 5-HT1A receptor agonist. Our results suggest a potential mechanism by which serotonergic agents may improve motor function in rats with chronic spinal cord injury. [source] Long-term effect of repetitive transcranial magnetic stimulation on motor function recovery after acute ischemic strokeACTA NEUROLOGICA SCANDINAVICA, Issue 1 2010E. M. Khedr Objective,,, Although there is evidence for short term benefits of rTMS in stroke, longer term effects have not been reported. The aim of the study was to evaluate the effect of two different frequencies of rTMS on motor recovery and on cortical excitability up to 1 year post-treatment. Methods,,, Forty-eight patients with acute ischemic stroke were randomly classified into three groups. The first two groups received real rTMS over motor cortex (3 and 10 Hz respectively) of the affected hemisphere and the third group received sham stimulation of the same site, daily for five consecutive days. Disability was assessed before, after fifth sessions, and then after 1, 2, 3 and 12 months. Cortical excitability was assessed for both hemispheres before and after the second and fifth sessions. Results,,, A significant ,rTMS × time' interaction was obtained indicating that real and sham rTMS had different effects on rating scales. This was because real rTMS produced greater improvement than sham that was evident even at one year follow-up. These improvements were associated with changes in cortical excitability over the period of treatment. Conclusion,,, These results confirm that real rTMS over motor cortex can enhance and maintain recovery and may be a useful add on therapy in treatment of acute stroke patients. [source] | |||||||||||||