Analysis of electromyographic activity of ankle muscles on stable and unstable surfaces with eyes open and closed

Introduction

Proprioceptive exercises are performed on a daily basis in physiotherapy with the use of different unstable platforms in order to improve joint stability using the mechanical and sensory properties of ligaments, joint capsule and integrated activity of the muscles surrounding the joint. Changes in the myoelectrical characteristics of the muscles during activity can be identified using surface electromyography (EMG), which provides important information on the behavior of muscles submitted to different types of load.

Objectives

The aim of the present study was to analyze the electromyographic activity of the tibialis anterior, tibialis posterior, peroneus longus, gastrocnemius lateralis and gastrocnemius medialis on stable and unstable surfaces with eyes open and closed.

Methodology

Twenty-five active, healthy, male and female individuals were submitted to an anthropometric evaluation and a protocol involving warm up and the electromyographic assessment of muscle activity on different surfaces. The order of the data collection was chosen randomly by lots [on stable ground or unstable platforms (trampoline, balance platform, proprioceptive disk and proprioceptive board) with eyes open and on a trampoline, balance platform and stable ground with eyes closed]. The individuals remained balanced on these surfaces for 15 s with the knee at 30° flexion in order to provide greater instability.

Results

There was a significant increase (p < 0.05) in muscle activity on the unstable surfaces, with the exception of the trampoline, which did not achieve statistically significant differences in relation to the stable ground. The tibialis anterior and peroneus longus exhibited the greatest electromyographic activity on all surfaces. The proprioceptive tests performed with eyes closed exhibited significantly greater electromyographic activity than with eyes open.

Conclusion

Proprioceptive exercises on unstable surfaces generated a significant increase in electromyographic activity, especially with eyes closed, and are therefore a valuable resource in the sensory-motor rehabilitation of the ankle.     

开放与密闭式吸引系统对呼吸机相关性肺炎发生率的影响研究进展

综述了开放式吸痰系统(OSS)、密闭式吸痰系统(CSS)与呼吸机相关性肺炎(VAP)的关系以及对VAP发生率的影响,突出OSS、CSS的优越性.     

Early versus later admission to postacute rehabilitation: impact on functional outcome after traumatic brain injury

OBJECTIVE: To examine the impact of participation in a postacute community reentry program on functional outcome after traumatic brain injury (TBI). DESIGN: Cohort, nonrandomized, intervention study. Pretest-posttest, follow-up design. SETTING: Nonprofit outpatient community reentry program affiliated with an inpatient rehabilitation hospital. PARTICIPANTS: Three groups of persons with moderate to severe TBI differing in length of time between injury and admission. The first group entered postacute rehabilitation within 6 months of injury (n=115); the second group, between 6 and 12 months (n=23); and the third group, greater than 12 months (n=29). INTERVENTIONS: Persons with TBI participated in a postacute community reentry program (average, 4.3mo) that emphasized (1) teaching compensatory strategies to address residual cognitive deficits; (2) arranging environmental supports to maximize functioning; (3) counseling and education to address personal and family adjustment and to improve accurate self-awareness; and (4) transition from simulated activities in the clinic to productive activities in the community. MAIN OUTCOME MEASURES: Disability Rating Scale, Supervision Rating Scale, and the Community Integration Questionnaire. RESULTS: All groups showed improvements between admission and discharge on measures of overall disability, independence, home competency, and productivity, and these gains were maintained at follow-up. For the group beginning postacute rehabilitation the earliest (<6mo postinjury) independence continued to improve after discharge. Community integration total score and home competency also continued to improve even after discharge. CONCLUSIONS: The results point toward the effectiveness of postacute rehabilitation in improving functional outcome after TBI even for persons who have reached stable neurologic recovery at 12 or more months postinjury.     

Effectiveness and side effects of closed and open suctioning: an experimental evaluation

Objective To compare the effectiveness of closed system suctioning (CSS) and open system suctioning (OSS) and the side effects on gas exchange and haemodynamics, during pressure-controlled ventilation (PCV) or continuous positive airway pressure (CPAP).Design Bench test and porcine lung injury model.Participants Twelve bronchoalveolar saline-lavaged pigs.Setting Research laboratory in a university hospital.Interventions In a mechanical lung, the efficacy of OSS and CSS with 12 and 14 Fr catheters were compared during volume-control ventilation, PCV, CPAP 0 or 10 cmH₂O by weighing the suction system before and after aspirating gel in a transparent trachea. Side effects were evaluated in the animals with the same ventilator settings during suctioning of 5, 10 or 20 s duration.Measurements and results Suctioning with 12 and 14 Fr catheters was significantly more efficient with OSS (1.9±0.1, 2.8±0.9 g) and with CSS during CPAP 0 cmH₂O (1.8±0.2, 4.2±0.5 g) as compared to CSS during PCV (0.2±0.2, 0.8±0.3 g) or CPAP 10 cmH₂O (0.0±0.1, 0.7±0.4 g), p<0.01 (means ± SD). OSS and CSS at CPAP 0 cmH₂O resulted in a marked decrease in SpO₂, mixed venous oxygen saturation and tracheal pressure, p<0.001, but the side effects were considerably fewer during CSS with PCV and CPAP 10 cmH₂O, p<0.05.Conclusions Irrespective of catheter size, OSS and CSS during CPAP 0 cmH₂O were markedly more effective than CSS during PCV and CPAP 10 cmH₂O but had worse side effects. However, the side effects lasted less than 5 min in this animal model. Suctioning should be performed effectively when absolutely indicated and the side effects handled adequately.This study was supported by grants from Medical Faculty of Gothenburg and Medical Society of Gothenburg.     

Potential impact of the new medicare prospective payment system on reimbursement for traumatic brain injury inpatient rehabilitation

OBJECTIVE: To evaluate the potential impact of the new Medicare prospective payment system (PPS) on traumatic brain injury (TBI) rehabilitation. DESIGN: Retrospective cohort study of patients with TBI. Patients were assigned to their appropriate case-mix group (CMG) based on Medicare criteria. SETTING: Fourteen urban rehabilitation facilities throughout the United States. PARTICIPANTS: Patients with TBI admitted to inpatient rehabilitation and enrolled in the Traumatic Brain Injury Model Systems from 1998 to 2001 (N=1807). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Cost of inpatient rehabilitation admission, length of stay (LOS), and functional outcomes. RESULTS: The median cost of inpatient rehabilitation for patients with TBI exceeded median PPS payments for all TBI CMGs by 16%. Only 3 of the 14 hospitals received reimbursement under PPS that exceeded costs for their TBI patients. CONCLUSIONS: Compared with current costs, the new Medicare payment system may reimburse facilities significantly less than their costs for the treatment of TBI. To maintain their current financial status, facilities may have to reduce LOS and/or reduce resource use. With a decreased LOS, inpatient rehabilitation services will have to improve FIM efficiency or discharge patients with lower discharge FIM scores.     

Effects of estrogen on patterns of brain activity at rest and during cognitive activity: a review of neuroimaging studies

Animal and human studies provide evidence of systematic effects of estrogen on cerebral activity and cognitive function. In this article, we review studies of the activational effects of estrogen on cerebral activity during rest and during the performance of cognitive tasks in pre- and postmenopausal women. The goal is twofold--to better understand evidence suggesting that estrogen influences brain functioning and argue for the importance of considering hormone effects when designing neuroimaging studies. Hormone-related increases in blood flow during the resting state have been documented in healthy elderly women, elderly women with cerebrovascular disease, and middle-aged postmenopausal women with early menopause. There is no reliable influence of estrogen on blood flow during the resting state in women with Alzheimer's disease. Hormone therapy has been associated with changes in brain activation patterns in middle-aged and elderly postmenopausal women during performance of verbal and figural memory tasks, providing critical biological support for the view that estrogen might protect against age-associated changes in cognition and lower the risk of Alzheimer's disease. There is a paucity of studies examining changes in brain activation patterns across the menstrual cycle and a need for randomized studies of hormone therapy in postmenopausal women to confirm findings from observational studies. General procedural guidelines for controlling and investigating hormone effects in neuroimaging studies are discussed.     

Classifying brain states and determining the discriminating activation patterns: Support Vector Machine on functional MRI data

In the present study, we applied the Support Vector Machine (SVM) algorithm to perform multivariate classification of brain states from whole functional magnetic resonance imaging (fMRI) volumes without prior selection of spatial features. In addition, we did a comparative analysis between the SVM and the Fisher Linear Discriminant (FLD) classifier. We applied the methods to two multisubject attention experiments: a face matching and a location matching task. We demonstrate that SVM outperforms FLD in classification performance as well as in robustness of the spatial maps obtained (i.e. discriminating volumes). In addition, the SVM discrimination maps had greater overlap with the general linear model (GLM) analysis compared to the FLD. The analysis presents two phases: during the training, the classifier algorithm finds the set of regions by which the two brain states can be best distinguished from each other. In the next phase, the test phase, given an fMRI volume from a new subject, the classifier predicts the subject's instantaneous brain state.     

Comparison of open and closed suction on safety,efficacy and nursing time in a paediatric intensive care unit

BackgroundEndotracheal suctioning (ETS) is one of the most common procedures performed in the paediatric intensive care. The two methods of endotracheal suctioning used are known as open and closed suction, but neither method has been shown to be the superior suction method in the Paediatric Intensive Care Unit (PICU).PurposeThe primary purpose was to compare open and closed suction methods from a physiological, safety and staff resource perspective.MethodsAll paediatric intensive care patients with an endotracheal tube were included. Between June and September 2011 alternative months were nominated as open or closed suction months. Data were prospectively collected including suction events, staff involved, time taken, use of saline, and change from pre-suction baseline in heart rate (HR), mean arterial pressure (MAP) and oxygen saturation (SpO₂). Blocked or dislodged ETTs were recorded as adverse events.FindingsClosed suction was performed more often per day (7.2 vs 6.0, p < 0.01), used significantly less nursing time (23 vs 38 min, p < 0.01) and had equivalent rates of adverse events compared to open suction (5 vs 3, p < 0.23). Saline lavage usage was significantly higher in the open suction group (18% vs 40%). Open suction demonstrated a greater reduction in SpO₂ and nearly three times the incidence of increases in HR and MAP compared to closed suction. Reductions in MAP or HR were comparable across the two methods.ConclusionsIn conclusion, CS could be performed with less staffing time and number of nurses, less physiological disturbances to our patients and no significant increases in adverse events.     

Three-dimensional locations and boundaries of motor and premotor cortices as defined by functional brain imaging: a meta-analysis

The mesial premotor cortex (pre-supplementary motor area and supplementary motor area proper), lateral premotor cortex (dorsal premotor cortex and ventral premotor cortex), and primary sensorimotor cortex (primary motor cortex and primary somatosensory cortex) have been identified as key cortical areas for sensorimotor function. However, the three-dimensional (3-D) anatomic boundaries between these regions remain unclear. In order to clarify the locations and boundaries for these six sensorimotor regions, we surveyed 126 articles describing pre-supplementary motor area, supplementary motor area proper, dorsal premotor cortex, ventral premotor cortex, primary motor cortex, and primary somatosensory cortex. Using strict inclusion criteria, we recorded the reported normalized stereotaxic coordinates (Talairach and Tournoux or MNI) from each experiment. We then computed the probability distributions describing the likelihood of activation, and characterized the shape, extent, and area of each sensorimotor region in 3-D. Additionally, we evaluated the nature of the overlap between the six sensorimotor regions. Using the findings from this meta-analysis, along with suggestions and guidelines of previous researchers, we developed the Human Motor Area Template (HMAT) that can be used for ROI analysis. HMAT is available through e-mail from the corresponding author.     

Comparative assessment of statistical brain MR image segmentation algorithms and their impact on partial volume correction in PET

Magnetic resonance imaging (MRI)-guided partial volume effect correction (PVC) in brain positron emission tomography (PET) is now a well-established approach to compensate the large bias in the estimate of regional radioactivity concentration, especially for small structures. The accuracy of the algorithms developed so far is, however, largely dependent on the performance of segmentation methods partitioning MRI brain data into its main classes, namely gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). A comparative evaluation of three brain MRI segmentation algorithms using simulated and clinical brain MR data was performed, and subsequently their impact on PVC in 18F-FDG and 18F-DOPA brain PET imaging was assessed. Two algorithms, the first is bundled in the Statistical Parametric Mapping (SPM2) package while the other is the Expectation Maximization Segmentation (EMS) algorithm, incorporate a priori probability images derived from MR images of a large number of subjects. The third, here referred to as the HBSA algorithm, is a histogram-based segmentation algorithm incorporating an Expectation Maximization approach to model a four-Gaussian mixture for both global and local histograms. Simulated under different combinations of noise and intensity non-uniformity, MR brain phantoms with known true volumes for the different brain classes were generated. The algorithms' performance was checked by calculating the kappa index assessing similarities with the "ground truth" as well as multiclass type I and type II errors including misclassification rates. The impact of image segmentation algorithms on PVC was then quantified using clinical data. The segmented tissues of patients' brain MRI were given as input to the region of interest (RoI)-based geometric transfer matrix (GTM) PVC algorithm, and quantitative comparisons were made. The results of digital MRI phantom studies suggest that the use of HBSA produces the best performance for WM classification. For GM classification, it is suggested to use the EMS. Segmentation performed on clinical MRI data show quite substantial differences, especially when lesions are present. For the particular case of PVC, SPM2 and EMS algorithms show very similar results and may be used interchangeably. The use of HBSA is not recommended for PVC. The partial volume corrected activities in some regions of the brain show quite large relative differences when performing paired analysis on 2 algorithms, implying a careful choice of the segmentation algorithm for GTM-based PVC.     

Effect of exergaming versus combined exercise on cognitive function and brain activation in frail older adults: A randomised controlled trial

BackgroundCognitive impairment is prevalent among frail older adults. Traditional exercise and exergaming positively affect cognition in healthy older people. However, few studies have investigated the effects of exergaming on cognition and brain activation in frail older adults.ObjectiveThis study compared the effect of Kinect based exergaming (EXER) and combined physical exercise (CPE) training on cognitive function and brain activation in frail older adults in Taiwan. We hypothesised that EXER would be superior to CPE in this population.MethodsWe randomised 46 community-dwelling frail older adults to the EXER or CPE group for 36 sessions (three 60-min training sessions per week) over 12 weeks. Outcome measures for cognitive function included global cognition measured by the Montreal Cognitive Assessment, executive function measured by the Executive Interview 25, verbal memory measured by the Chinese version of the California Verbal Learning Test, attention measured by the Stroop Colour and Word Test and Trail Making Test (part B), and working memory measured by spatial n-back tests. Prefrontal cortex activation during the global cognition test was documented with functional near-infrared spectroscopy (fNIRS).ResultsBoth groups improved significantly in global cognition (P < 0.05), executive function (P < 0.05), and attention (P < 0.05) after the 12-week intervention. The group × time interaction indicated that EXER training significantly enhanced global cognition more than CPE training (F(1,44) = 5.277, P = 0.026). Moreover, only the EXER group showed significant improvements in verbal (P < 0.05) and working (P < 0.05) memory after the intervention. The fNIRS hemodynamics data revealed decreased activation in prefrontal cortices of both groups (P < 0.05) during the post-training cognitive assessment, thereby suggesting greater neural efficiency; however, we found no significant group difference.ConclusionIn frail older adults, exergaming and CPE could improve cognitive function, most likely by increasing neural efficiency. Moreover, exergaming may be superior to CPE, particularly in improving global cognition.     

脑死亡判定中呼吸暂停试验临床实施的可行性及对血压和心率的影响

目的探讨脑死亡判定标准中呼吸暂停试验临床实施的可行性及对平均动脉压(MAP)、心率(HR)的影响。方法对22例临床可疑的脑死亡患者进行呼吸暂停试验,先经呼吸机吸入纯氧10min,再停机并经插至气管隆突水平的导管以6L/min纯氧供氧10min,观察患者有无自主呼吸,并分别测定其充氧前、充氧后、停机后的动脉血pH值、PaO2、PaCO2的变化,及停机后MAP、HR的动态变化。结果试验过程中,22例患者无一例出现自主呼吸,其中16例试验结束时PaCO2≥60mmHg。停机后所有患者pH值明显下降、PaCO2明显升高(P<0.01),充氧后PaO2明显升高(P<0.05),而停机后PaO2无明显下降趋势(P>0.05)。停机后患者MAP、HR均逐渐下降,且各组停机后与停机前比较均有显著差异(P<0.05),至停机8min时下降尤为显著,再通气后HR回升迅速,而MAP则缓慢。结论呼吸暂停试验为判定脑死亡的关键步骤之一,停机后MAP、HR尽管逐渐下降,但不发生低氧血症,若纠正停机前的过度通气,并控制停机时间在8min内,临床上是可行和安全的。     

Plasma atrial natriuretic peptide and brain natriuretic peptide are increased in septic shock: impact of interleukin-6 and sepsis-associated left ventricular dysfunction

Objective Interest has recently focused on the use of neurohormonal markers such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) as indices of left ventricular systolic dysfunction and prognosis in heart failure. Also, peptides belonging to the interleukin-6 (IL-6) family have been shown to induce ANP and BNP secretion. We hypothesized that BNP and ANP spillover in the peripheral circulation reflects left ventricular dysfunction and IL-6 production in septic shock.Design and setting Retrospective, clinical study in the medical intensive care unit of a university hospital.Patients and participants 17 patients with septic shock and 19 control subjects.Interventions Collection of clinical and demographic data in relation to ANP, BNP, IL-6, and soluble TNF receptors (sTNF-R-p55, sTNF-R-p75) in plasma over a period of 4 days.Measurements and results In septic shock we found a significant increase in ANP (82.7±9.9 vs. 14.9±1.2 pg/ml) and BNP (12.4±3.6 vs. 5.5±0.7 pg/ml). Plasma ANP peaked together with IL-6. Peaks of ANP and IL-6 were significantly correlated (r=0.73; p<0.01). BNP was inversely correlated to cardiac index (r=–0.56; p<0.05).Conclusions ANP and BNP increase significantly in patients with septic shock. BNP reflects left ventricular dysfunction. ANP is related to IL-6 production rather than to cardiovascular dysfunction.     

Common data elements for research on traumatic brain injury and psychological health: current status and future development

Whyte J, Vasterling J, Manley GT. Common data elements for research on traumatic brain injury and psychological health: current status and future development.The National Institute of Neurologic Disorders and Stroke, Defense Centers of Excellence for Psychological Health and Traumatic Brain Injury, National Institute on Disability and Rehabilitation Research, and Defense and Veterans Brain Injury Center jointly supported an effort to develop common data elements (CDEs, ie, consensus-based content domains of importance and recommended ways to measure them) for research on traumatic brain injury and psychological health. The authors served as participants in this effort as well as editors of the resulting articles. This article describes the current status of this multiagency endeavor, the obstacles encountered, and possible directions for future development. Challenges that occurred within the working groups that developed the CDE recommendations and similarities and differences among the articles that describe those recommendations were reviewed. Across all of the working groups, there were challenges in striking a balance between specificity in recommendations to researchers and the need to tailor the selection of variables to specific study aims. The domains addressed by the different working groups varied in the research available to guide the selection of important content areas to be measured and the specific tools for measuring them. The working groups also addressed this challenge in somewhat different ways. The CDE effort must enhance consensus among researchers with similar interests while not stifling innovation and scientific rigor. This will require regular updating of the recommendations and may benefit from more standardized criteria for the selection of important content areas and measurement tools across domains.     

Work-related difficulties in patients with traumatic brain injury: a systematic review on predictors and associated factors

Purpose: To address the content of work-related difficulties and explore which variables are associated to or determinants of these difficulties in persons that suffered from Traumatic Brain Injury (TBI). Method: Papers published between 1993 and February 2015 were included. Quality was judged as poor, acceptable, good or excellent. Determinants were extracted from longitudinal data, associated variables from cross-sectional data; variables were grouped by similarity. Evidence was judged as strong if the same results were reported by two or more good studies; limited if reported by one good and some acceptable studies. Results: Forty-two papers were selected (25,756 patients). Work-related difficulties were referred as unemployment, job instability or job cessation. Strong evidence of impact was found for: low educational level, pre-injury unemployment, Glasgow Coma Scale score and TBI severity, length of stay in acute and rehabilitation settings, lower Functional Independence Measure scores and presence of cognitive disturbances. Discussion: Evidence on the effect of rehabilitation interventions on TBI patients’ work-related difficulties exists, but is poorly measured. Future studies should address the sustainability of holistic and tailored interventions targeting employees, employers and workplaces and aimed to reduce the gap between work duties and worker’s abilities, using appropriate assessment instruments measuring difficulties in work activities.

• Implications for rehabilitation

• Traumatic Brain Injury (TBI) primarily affects young persons of working age causing a broad range of motor, sensory and cognitive impairments. A combination of variables related both to pre-morbid and to injury-related factors predict and are associated to work-related difficulties.

• While demographic and injury characteristics cannot be modified, some TBI outcomes (e.g. cognitive impairments or functional status) may be addressed by specific rehabilitative interventions: the knowledge of the specific work-related difficulties of TBI patients is of importance to tailor rehabilitation programs that maximize vocational outcomes.

• Rehabilitation researchers should give attention to vocational issues and use assessment instruments addressing the difficulties in work-related activities, in order to demonstrate the benefits of rehabilitative interventions on TBI patients’ ability to work.

     

A biopsychosocial perspective on adjustment and quality of life following brain tumor: A systematic evaluation of the literature

Purpose.?To systematically evaluate the literature on quality of life and adjustment to brain tumor from a biopsychosocial perspective.

Methods.?On the basis of the cancer and brain injury literature, a biopsychosocial organisational framework was initially developed to support an evaluative review of the brain tumor literature. This framework consisted of four themes relating to pre-illness characteristics, neuropathology, personal appraisals and reactions and social support. Electronic searches of Medline, PsycINFO and CINAHL databases identified 48 empirical studies (1980–2007) that investigated factors associated with quality of life or the adjustment of adults with brain tumor. A review of studies within each theme appraised these findings and evaluated the quality of methodology and extent to which biopsychosocial perspectives have guided investigations.

Results.?Overall, the review identified consistent associations between depression, performance status, fatigue and quality of life. Seven multivariate studies with strong methodology that adopted a biopsychosocial perspective were found. In general, the relationships among pre-illness and brain tumor characteristics, psychosocial variables and quality of life were unclear and various gaps in the literature emerged.

Conclusions.?Empirical findings within a biopsychosocial perspective may guide the development and delivery of support services for individuals with brain tumor; however, many important areas exist for future research.     

A survey on patients admitted in severe coma: implications for brain death identification and organ donation

Objective To identify factors to improve the identification of brain dead patients in intensive care units (ICUs).Design and setting Prospective study conducted in 79 ICUs in 54 hospitals.Patients All hospitalized patients with a Glasgow Coma Scale (GCS) score less than 8.Measurements and results During the study period hospital staff completed a form for each patient with a GCS less than 8. Hospital information units provided us with statistics from the discharge forms. The characteristics of the hospitals were also recorded. We included a total of 792 patients with a GCS less than 8; 120 of these patients were diagnosed as being clinically brain dead (15.1%). These patients accounted for 11.8% of the comatose patients in ICUs, 11.7% of the deaths occurring in ICUs, and 3.3% of the deaths that occurred in the hospital during the study period. Two multivariate linear regressions were performed to predict the number of clinically brain dead patients in the ICUs. The regression analyses included causes of death or causes of coma, and hospital characteristics. The presence of a coordination team and the number of transplant coordinators were positively associated with the number of brain dead patients in both models. The number of patients carried to the ICU by a mobile emergency unit was also positively associated in the model with causes of coma.Conclusions Increasing the number of hospital coordinators and collaboration with mobile emergency units should lead to the identification of more brain dead patients among comatose patients in ICUs.An editorial regarding this article can be found in the same issue     

巨刺法对脑缺血再灌注损伤大鼠运动功能、脑影像结构及PI3K/AKT信号通路的影响

目的:观察巨刺法对脑缺血再灌注损伤模型大鼠运动功能及影像学结构的影响,并探讨其可能的作用机制。方法:将30例健康雄性SD大鼠随机分为假手术组、模型组及巨刺组,各10只。模型组及巨刺组大鼠接受改良局灶性脑缺血再灌注大脑中动脉栓塞(MCAO)模型制备,假手术组仅接受切开皮肤+分离血管+皮肤缝合处理。巨刺组进行巨刺曲池穴及足三里穴7d,模型组及假手术组仅接受模拟捉拿及相应穴位点触。各组采用神经行为学评分评估大鼠运动功能,H反射评估大鼠肌张力状况,TTC染色及MRI观察脑梗死体积,Western Blot检测PI3K、AKT、pAKT水平,免疫组化检测Caspase-3的表达,Tunel检测神经元细胞调亡情况。结果:巨刺法可明显降低MCAO大鼠的神经行为学评分、H反射的潜伏期、脑梗死体积、神经元凋亡率以及Caspase-3表达,增加H反射的波幅、PI3K、p-AKT表达水平。结论:巨刺法可明显改善脑缺血再灌注损伤大鼠的运动功能,其作用机制可能与介导PI3K/AKT信号通路有关。     

Caudate nucleus: influence of dopaminergic input on sequence learning and brain activation in Parkinsonism

In this study, we tested the hypotheses that (1) the acquisition of sequential information is related to the integrity of dopaminergic input to the caudate nucleus; and (2) the integrity of dopaminergic input to the caudate nucleus correlates significantly with brain activation during sequence acquisition. Twelve early stage Parkinson's disease (PD) patients and six age-matched healthy volunteers were scanned using a dual tracer PET imaging design. All subjects were scanned with [(18)F]fluoropropyl-betaCIT (FPCIT) to measure striatal dopamine transporter (DAT) binding and with [(15)O]water to assess activation during a sequence learning task where movements were made to a repeating sequence of eight targets. Caudate and putamen DAT binding in the PD cohort was reduced by 15% and 43%, respectively. In PD, caudate DAT binding correlated with target acquisition (R = 0.57, P < 0.05), while putamen DAT binding did not correlate with performance. In volunteers, caudate DAT binding correlated with learning-related activation (P < 0.05, corrected for multiple comparisons) in the left dorsolateral and ventral prefrontal cortices, the anterior cingulate and premotor regions, and the right cerebellum. A significant correlation with caudate DAT binding was additionally detected in the right anteromedial thalamus, extending into the rostral midbrain. By contrast, in the PD cohort, most of these regional relationships were lost: Only ventral and dorsolateral prefrontal cortex activation correlated with caudate dopaminergic tone. Our findings suggest that sequence learning is normally associated with tight coupling between dopaminergic input to the caudate and thalamo-cortical functional activity. Despite minimal reductions in nigro-caudate input, PD patients demonstrate a loss of this coupling early in the disease.