Xun Luo

Correlation of Fractional Anisotropy With Motor Recovery in Patients With Stroke After Postacute Rehabilitation

OBJECTIVE To investigate the relation between fractional anisotropy (FA), a suggested biomarker for tissue integrity, and motor recovery in patients with stroke after postacute rehabilitation. DESIGN Retrospective study. SETTING Acute rehabilitation hospital. PARTICIPANTS Subjects (N=43) diagnosed with ischemic stroke (n=28) and hemorrhagic stroke (n=15). The average age for subjects was 68±14 years. INTERVENTIONS Magnetic resonance imaging and diffusion tensor imaging were conducted on all patients. MAIN OUTCOME MEASURES The admission and discharge motor subscores of the FIM were obtained from medical records, and relative gain was calculated using the Montebello Rehabilitation Factor Score (MRFS). K-means cluster analysis (K=3) using both the MRFS and the gain of the FIM motor subscore (ΔFIM) was performed. Analysis of variance was used to determine the difference in FA among the clusters. Spearman analysis was conducted to examine the relation between FA, ΔFIM, and MRFS in each cluster. RESULTS FA was significantly higher in the clusters of good and moderate recovery in the corticospinal tract (CST), peduncle, and posterior limb of the internal capsule bilaterally (all P<.05) compared with the poor recovery group. Significant positive correlations were observed in multiple regions along the CST between FA, ΔFIM, and MRFS in the clusters of good and moderate recovery, but not in the poor recovery group. CONCLUSIONS Our results showed an association between FA values within the corticospinal tract and motor recovery in patients with stroke undergoing postacute rehabilitation. This finding may help to identify novel targets for new interventions to promote stroke recovery.

Gait disorder as a predictor of spatial learning and memory impairment in aged mice

Objective To investigate whether gait dysfunction is a predictor of severe spatial learning and memory impairment in aged mice. Methods A total of 100 12-month-old male mice that had no obvious abnormal motor ability and whose Morris water maze performances were not significantly different from those of two-month-old male mice were selected for the study. The selected aged mice were then divided into abnormal or normal gait groups according to the results from the quantitative gait assessment. Gaits of aged mice were defined as abnormal when the values of quantitative gait parameters were two standard deviations (SD) lower or higher than those of 2-month-old male mice. Gait parameters included stride length, variability of stride length, base of support, cadence, and average speed. After nine months, mice exhibiting severe spatial learning and memory impairment were separated from mice with mild or no cognitive dysfunction. The rate of severe spatial learning and memory impairment in the abnormal and normal gait groups was tested by a chi-square test and the correlation between gait dysfunction and decline in cognitive function was tested using a diagnostic test. Results The 12-month-old aged mice were divided into a normal gait group (n = 75) and an abnormal gait group (n = 25). Nine months later, three mice in the normal gait group and two mice in the abnormal gait group had died. The remaining mice were subjected to the Morris water maze again, and 17 out of 23 mice in the abnormal gait group had developed severe spatial learning and memory impairment, including six with stride length deficits, 15 with coefficient of variation (CV) in stride length, two with base of support (BOS) deficits, five with cadence dysfunction, and six with average speed deficits. In contrast, only 15 out of 72 mice in the normal gait group developed severe spatial learning and memory impairment. The rate of severe spatial learning and memory impairment was significantly higher in the abnormal gait group as compared to that in the normal gait group (x = 21.986, P < 0.001). All five parameters used to assess gait predicted severe spatial learning and memory impairment in aged mice (P < 0.01). However, the difference of the area under the ROC (receiver operating characteristic) curve for each quantitative gait parameter was not statistically significant. Conclusion Gait disorders are a predictor of severe spatial learning and memory impairment in aged mice, and stride length, variability of stride length, base of support, cadence, and average speed are all sensitive parameters for assessing gait.

Increased Th17/Treg Ratio in Poststroke Fatigue

Fatigue is a major debilitating symptom after stroke. The biological mechanisms underlying poststroke fatigue (PFS) are unknown. We hypothesized that PSF is associated with an alteration in the balance between Th17 and Treg cells. To test this hypothesis we assessed fatigue in 30 stroke survivors using the Fatigue Scale for Motor and Cognitive Functions (FSMC). Peripheral blood was collected for assessment of Th17 and Treg cell populations and measurement of interleukin-10 (IL-10). Participants were dichotomized into severe fatigue (n = 14) and low-moderate fatigue (n = 16) groups by K-mean cluster analysis of FSMC scores. There were no group differences in age, gender, stroke type, stroke severity, or time since stroke. Stroke survivors in the severe fatigue group reported greater anxiety (p = 0.004) and depression (p = 0.001) than in the low-moderate fatigue group. The ratio of Th17 to Treg cells was significantly increased in the severe fatigue group relative to the mild-moderate fatigue group (p = 0.035). Serum levels of IL-10 negatively correlated withTh17/Treg ratio (r = −0.408,  p = 0.025). Our preliminary findings suggest that an imbalance in the Th17/Treg ratio is associated with the severity of PSF.

The Serum BDNF Level Offers Minimum Predictive Value for Motor Function Recovery After Stroke

Brain-derived neurotrophic factor (BDNF) plays an important role in neuroplasticity and neurogenesis following ischemic and non-ischemic brain injury. The predictive value of BDNF for short-term outcome after stroke is controversial. The objective of this study was to investigate the relationship among serum BDNF level, fractional anisotropy (FA), and functional outcome during post-acute stroke rehabilitation. Serum BDNF levels were measured on admission to an acute inpatient rehabilitation hospital. The primary functional outcome was functional independence measure (FIM) motor subscore at discharge. The secondary outcome measures were FIM total score at discharge, FIM motor subscore on admission, length of stay in the hospital, and discharge destination. We investigated the relationship among the level of serum BDNF and FA as well as functional outcome measures. Three hundred forty-eight consecutive stroke subjects were included in the analysis. Serum BDNF levels on admission were statistically but not clinically correlated with FIM motor subscore at discharge (r = 0.173, P = 0.001) and FIM total score at discharge (r = 0.155, P = 0.004). Receiver operating characteristic (ROC) analysis of BDNF as a predictor for FIM motor subscore improvement showed low accuracy of prediction with an area under the curve (AUC) of 0.581 (P = 0.026). Serum BDNF significantly correlated with FA in the high FIM motor group (n = 10, r = 0.609, P = 0.031) but not in the low FIM motor group (n = 11, r = − 0.132, P = 0.349). The serum BDNF level alone offers minimum predictive value for recovery of motor function during post-acute rehabilitation. Our findings suggest that serum BDNF level may be correlated with FA.

Poster 63: Association of BDNF Val66Met with Post-Stroke Functional Recovery

Disclosures: Morgan Callahan: I Have No Relevant Financial Relationships To Disclose Objective: 1) To determine if there are injury level differences between physical barrier perception and behavior; 2) To determine if there is a relationship between physical barrier perception and behavior. Design: Cross-sectional case series Setting: Academic Medical Laboratory Participants: 50 manual wheelchair users with chronic spinal cord injury; Tetraplegia (TP)1⁄419, Paraplegia (PP)1⁄431 Interventions: Not Applicable Main Outcome Measures: All participants completed the following assessments; 1) Self-Reported Avoidances and Encounters of Environmental Features in the Environmental Aspects of Mobility Questionnaire (EAMQ); and 2) Physical/Structural Subdomain of the Perception of Environmental Barriers in the Craig Hospital Inventory of Environmental Factor (CHIEF). Results: There was no significant difference in perception of physical barriers between lesion levels (P 1⁄4.79; TP median 2, interquartile range (IQR) 1-12; PP median 3, IQR 1-11). However, behavioral differences were exhibited by injury level. Individuals with paraplegia had a higher rate of encounters with environmental features in 3 of 9 EAMQ domains (temporal, terrain, and postural, P .03), and a lower rate of avoidances per encounter in 3 of 8 EAMQ domains (temporal, terrain, and total, P .05). For individuals with tetraplegia, perception of barriers was inversely associated with encounters and positively associated with avoidances in 1 of 9 EAMQ domains (density, P .05). For individuals with paraplegia, perception of barriers was inversely associated with encounters in 2 of 9 EAMQ domains (attention and total, P .05), but there were no associations with avoidances. Conclusions: Our results indicate a divergence between perception and behavior, with motor impairment differences captured by behavior but not perception. In addition, there were limited associations between behavior and perception. More research is required on if barrier perception, behavior, or both influence participation, so that rehabilitation programs can better tailor interventions to enhance participation. Level of Evidence: Level IV

Poster 64: Targeted Metabolomic Profiling of Human Serum Reveals Association of Elevated Arginine with Poor Functional Recovery After Stroke

CIs in patients with moderate to severe TBI was 6% and 7.5%, respectively, both higher than a recent study utilizing ICD coding. In patients with TBI, traumatic arterial injuries are being increasingly recognized and along with CIs, are more likely with greater severity of TBI. Further research is recommended on the outcome implications of concomitant cerebrovascular injury. Level of Evidence: Level II

Cerebral Responses to Acupuncture at GV24 and Bilateral GB13 in Rat Models of Alzheimer’s Disease

Acupuncture has been widely used in China to treat neurological diseases including Alzheimers disease (AD). However, its mechanism remains unclear. In the present study, eighty healthy Wistar rats were divided into a normal control group (n = 15) and premodel group (n = 65). Forty-five rats that met the criteria for the AD model were then randomly divided into the model group (MG), the nonacupoint group (NG), and the acupoint group (AG). All rats received positron emission tomography (PET) scanning, and the images were analyzed with Statistical Parametric Mapping 8.0. MG exhibited hypometabolism in the olfactory bulb, insular cortex, orbital cortex, prelimbic cortex, striatum, parietal association cortex, visual cortex, cingulate gyrus, and retrosplenial cortex. AG exhibited prominent and extensive hypermetabolism in the thalamus, hypothalamus, bed nucleus of the stria terminalis, cerebral peduncle, midbrain tegmentum, and pontine tegmentum compared to NG. These results demonstrated that acupuncturing at GV24 and bilateral GB13 acupoints may improve the learning and memory abilities of the AD rats, probably via altering cerebral glucose metabolism (CGM) in the hypothalamus, thalamus, and brain stem. The observed effects of acupuncture may be caused by regulating the distribution of certain kinds of neurotransmitters and enhancing synaptic plasticity.

Surface Modification with ECM-Inspired SDF-1α/Laminin-Loaded Nanocoating for Vascular Wound Healing

Surface biomimetic modification with extra-cellular matrix (ECM)-derived biomolecules is an emerging potential method of accelerating the healing of vascular stent lesions. However, insufficient capacity of the constructed biofunctional layer in maintaining its long-term efficiency and preventing thrombus and neointimal hyperplasia continue to be major limitations in clinical application. On the basis of the structure and function of ECM, in this study, we constructed a novel stromal cell-derived factor-1α (SDF-1α)/laminin-loaded nanocoating on the 316L stainless steel (SS) surface to provide improved function in modulation of vascular remodeling. The modified surface was found to control delivery of biomolecules and exhibit promising potential to provide stage-adjusted treatment after injury. An in vitro biocompatibility study suggested that the constructed layer may effectively prevent thrombosis formation by inhibiting platelet adhesion and activation, while accelerating endothelium regeneration by inducing endothelial cell (EC) migration and endothelial progenitor cell (EPC) aggregation. An in vivo animal test further demonstrated that the nanocoating may prevent thrombus and neointimal hyperplasia after implantation for 3 months. Therefore, the ECM-inspired nanocoating described in this study is a promising novel approach for vascular stent surface modification.

Poster 116 Association of Serum Brain-Derived Neurotrophic Factor with Functional Independence Measure after Ischemic Stroke

oxcarbazepine and topiramate to phenytoin and lamotrigine, bradycardia and hypothermia significantly improved. Lamotrigine dose was slowly increased prior to discontinuation of phenytoin without significant change in vital signs. Discussion: Guidelines exist for treatment of post-traumatic seizures after a traumatic brain injury based upon timing (i.e., immediate, early, late). Adverse effects from these medications can be pronounced, especially when large dosages and multiple agents are necessary to treat refractory seizures. Rare reports exist associating levetiracetam with bradycardia and adjuvant use of topiramate with hypothermia. To our knowledge, there is no association between injury to the Guillain Mollaret Triangle and bradycardia or hypothermia. Conclusion: This case highlights the complicated management of post-traumatic seizures after traumatic brain injury as well as the association in this case of severe bradycardia and hypothermia with levetiracetam and topiramate use.