Wound healing is accelerated by agonists of adenosine A2 (G alpha s-linked) receptors

The complete healing of wounds is the final step in a highly regulated response to injury. Although many of the molecular mediators and cellular events of healing are known, their manipulation for the enhancement and acceleration of wound closure has not proven practical as yet. We and others have established that adenosine is a potent regulator of the inflammatory response, which is a component of wound healing. We now report that ligation of the G alpha s-linked adenosine receptors on the cells of an artificial wound dramatically alters the kinetics of wound closure. Excisional wound closure in normal, healthy mice was significantly accelerated by topical application of the specific A2A receptor agonist CGS-21680 (50% closure by day 2 in A2 receptor antagonists. In rats rendered diabetic (streptozotocin-induced diabetes mellitus) wound healing was impaired as compared to nondiabetic rats; CGS-21680 significantly increased the rate of wound healing in both nondiabetic and diabetic rats. Indeed, the rate of wound healing in the CGS-21680-treated diabetic rats was greater than or equal to that observed in untreated normal rats. These results appear to constitute the first evidence that a small molecule, such as an adenosine receptor agonist, accelerates wound healing in both normal animals and in animals with impaired wound healing.

Chronic Stroke Outcome Measures for Motor Function Intervention Trials: Expert Panel Recommendations

BACKGROUND

About half of survivors with stroke experience severe and significant long-term disability. The purpose of this article is to review the state of the science and to make recommendations for measuring patient-centric outcomes in interventions for motor improvement in the chronic stroke phase.

METHODS AND RESULTS

A 9-member expert panel reviewed evidence to identify measures of upper and lower extremity function used to date as outcomes in trials with patients who experienced a stroke ≥6 months before assessment. Outcome measures were screened using StrokEDGE consensus panel recommendations, and evaluated for availability of a published minimal clinically important difference. Measures meeting these criteria were further evaluated with regard to their level of measurement, psychometric properties, and ability of minimal clinically important difference to capture gains associated with improved function and clinical relevance to patients, to arrive at recommendations. A systematic literature review yielded 115 clinical trials of upper and lower extremity function in chronic stroke that used a total of 34 outcome measures. Seven of these had published minimal clinically important differences and were recommended or highly recommended by StrokEDGE. Those are the Fugl-Meyer Upper Extremity and Lower Extremity scales, Wolf Motor Function Test, Action Research Arm Test, Ten-Meter and Six-Minute Walk Tests, and the Stroke Impact Scale. All had evidence for their psychometric performance, although the strength of evidence for validity varied, especially in populations with chronic stroke Fugl-Meyer Upper and Lower Extremity scales showing the strongest evidence for validity.

CONCLUSIONS

The panel recommends that the Fugl-Meyer Upper and Lower Extremity scales be used as primary outcomes in intervention trials targeting motor function in populations with chronic stroke. The other 6 measures are recommended as secondary outcomes.

Use of mental practice to improve upper-limb recovery after stroke: a systematic review

OBJECTIVE

We sought to determine whether mental practice is an effective intervention to improve upper-limb recovery after stroke.

METHOD

We conducted a systematic review of the literature, searching electronic databases for the years 1985 to February 2009. We selected studies according to specified criteria, rated each study for level of evidence, and summarized study elements.

RESULTS

Studies differed with respect to design, patient characteristics, intervention protocols, and outcome measures. All studies used imagery of tasks involving movement of the impaired limb. The length of the interventions and number of practice hours varied. Results suggest that mental practice combined with physical practice improves upper-limb recovery.

CONCLUSION

When added to physical practice, mental practice is an effective intervention. However, generalizations are difficult to make. Further research is warranted to determine who will benefit from training, the dosing needed, the most effective protocols, whether improvements are retained, and whether mental practice affects perceived occupational performance.

Motor imagery training in hemiplegic cerebral palsy: a potentially useful therapeutic tool for rehabilitation

Converging evidence indicates that motor deficits in cerebral palsy (CP) are related not only to problems with execution, but also to impaired motor planning. Current rehabilitation mainly focuses on alleviating compromised motor execution. Motor imagery is a promising method of training the more 'cognitive' aspects of motor behaviour, and may, therefore, be effective in facilitating motor planning in patients with CP. In this review first we present the specific motor planning problems in CP followed by a discussion of motor imagery and its use in clinical practice. Second, we present the steps to be taken before motor imagery can be used for rehabilitation of upper limb functioning in CP. Motor imagery training has been shown to be a useful addition to existing rehabilitation protocols for poststroke rehabilitation. No such study has been conducted in CP. The age at which children can reliably use motor imagery, as well as the specific way in which motor imagery training needs to be implemented, must be researched before motor imagery training can be employed in children with CP. Based on the positive results for poststroke rehabilitation, and in light of the motor problems in CP, motor imagery training may be a valuable additional tool for rehabilitation in CP.

Regulation of expression of granulocyte-macrophage colony-stimulating factor in human bronchial epithelial cells: roles of protein kinase C and mitogen-activated protein kinases

GM-CSF has a major role in the immune and inflammatory milieu of the airway. Airway epithelial cells (AEC) are among the first targets of environmental stimuli and local cytokines, in response to which they can produce GM-CSF. The regulation of GM-CSF is only minimally understood in AEC. We hypothesized that GM-CSF expression in AEC would result from activation of protein kinase C (PKC) and subsequent activation of the extracellular signal-regulated kinase (MAPKerk1/2) pathway, so we investigated signal transduction pathways in human primary culture bronchial epithelial cells (HBECs). TNF-alpha, IL-1beta, and PMA induced the release of GM-CSF in HBECs. The robust response to PMA was not detected in SV40 adenovirus-transformed normal human bronchial epithelial cells (BEAS-2B). PMA and TNF-alpha stimulation of GM-CSF required activation of PKC (inhibition by staurosporine and bisindolylmaleimide I). GM-CSF expression was up-regulated by a nonphorbol PKC activator, but not by an inactive PMA analogue. PMA-induced GM-CSF production in HBECs did not require a Ca2+ ionophore and was not inhibited by cyclosporin A. Activation of MAPKerk1/2 via PKC was associated with and was required for GM-CSF production induced by PMA and TNF-alpha. The data demonstrate regulation of GM-CSF in HBECs by PKC pathways converging on the MAPKerk1/2 pathway and further define cell-specific regulation critical for local airway responses.

Biomarkers of lung inflammation in recreational joggers exposed to ozone

Humans exhibit an acute inflammatory response in the lungs after controlled laboratory exposure to ozone. The present study was designed to test whether biomarkers of inflammation are detectable in humans exposed to ozone and associated copollutants under natural conditions outdoors. Bronchoscopy with bronchoalveolar lavage (BAL) was carried out on 19 normal volunteer joggers from Governors Island, NY, who exercised in the afternoon during the 1992 summer (S1) season. Fifteen subjects were retested during the following, low ozone, winter season (W). The BAL protocol involved an initial instillation of 20 ml saline followed by four sequential 50-ml saline washes carried out in both the right middle lobe and the lingula. The eight 50-ml samples were pooled as the 'alveolar' sample. Analyses performed on the alveolar lavage samples included cell differentials, release of IL-8, TNF-alpha, and reactive oxygen species (ROS) by pooled cells, and levels of IL-8, protein, LDH, fibronectin, alpha1-antitrypsin (alpha1-AT), complement fragment 3a (C3a), and prostaglandin E2 (PGE2) in lavage fluids. Release of ROS by stimulated BAL cells was lower in S1 than in W (p = 0.03). In contrast, LDH levels in BAL fluids were 2-fold higher in S1 than in W (p = 0.02), as were IL-8 (p = 0.12) and PGE2 (p = 0.06). These results suggest a possible ongoing inflammatory response in the lungs of recreational joggers exposed to ozone and associated copollutants during the summer months.

Effect of imagery perspective on occupational performance after stroke: a randomized controlled trial

OBJECTIVE

This preliminary study sought to determine whether the imagery perspective used during mental practice (MP) differentially influenced performance outcomes after stroke.

METHOD

Nineteen participants with unilateral subacute stroke (9 men and 10 women, ages 28-77) were randomly allocated to one of three groups. All groups received 30-min occupational therapy sessions 2×/wk for 6 wk. Experimental groups received MP training in functional tasks using either an internal or an external perspective; the control group received relaxation imagery training. Participants were pre- and posttested using the Fugl-Meyer Motor Assessment (FMA), the Jebsen-Taylor Test of Hand Function (JTTHF), and the Canadian Occupational Performance Measure (COPM).

RESULTS

At posttest, the internal and external experimental groups showed statistically similar improvements on the FMA and JTTHF (p < .05). All groups improved on the COPM (p < .05).

CONCLUSION

MP combined with occupational therapy improves upper-extremity recovery after stroke. MP does not appear to enhance self-perception of performance. This preliminary study suggests that imagery perspective may not be an important variable in MP interventions.

Effectiveness of interventions to improve occupational performance of people with motor impairments after stroke: an evidence-based review

We conducted a review to determine the effectiveness of interventions to improve occupational performance in people with motor impairments after stroke as part of the American Occupational Therapy Association's Evidence-Based Practice Project. One hundred forty-nine studies met inclusion criteria. Findings related to key outcomes from select interventions are presented. Results suggest that a variety of effective interventions are available to improve occupational performance after stroke. Evidence suggests that repetitive task practice, constraint-induced or modified constraint-induced movement therapy, strengthening and exercise, mental practice, virtual reality, mirror therapy, and action observation can improve upper-extremity function, balance and mobility, and/or activity and participation. Commonalities among several of the effective interventions include the use of goal-directed, individualized tasks that promote frequent repetitions of task-related or task-specific movements.

A Taxonomy of Functional Upper Extremity Motion

Background: Functional upper extremity (UE) motion enables humans to execute activities of daily living (ADLs). There currently exists no universal language to systematically characterize this type of motion or its fundamental building blocks, called functional primitives. Without a standardized classification approach, pooling mechanistic knowledge and unpacking rehabilitation content will remain challenging.

Methods: We created a taxonomy to characterize functional UE motions occurring during ADLs, classifying them by motion presence, temporal cyclicity, upper body effector, and contact type. We identified five functional primitives by their phenotype and purpose: reach, reposition, transport, stabilize, and idle. The taxonomy was assessed for its validity and interrater reliability in right-paretic chronic stroke patients performing a selection of ADL tasks. We applied the taxonomy to identify the primitive content and motion characteristics of these tasks, and to evaluate the influence of impairment level on these outcomes.

Results: The taxonomy could account for all motions in the sampled activities. Interrater reliability was high for primitive identification (Cohen's kappa = 0.95–0.99). Using the taxonomy, the ADL tasks were found to be composed primarily of transport and stabilize primitives mainly executed with discrete, proximal motions. Compared to mildly impaired patients, moderately impaired patients used more repeated reaches and axial-proximal UE motion to execute the tasks.

Conclusions: The proposed taxonomy yields objective, quantitative data on human functional UE motion. This new method could facilitate the decomposition and quantification of UE rehabilitation, the characterization of functional abnormality after stroke, and the mechanistic examination of shared behavior in motor studies.

Effectiveness of Interventions to Improve Occupational Performance of People With Cognitive Impairments After Stroke: An Evidence-Based Review

This evidence-based review was conducted to determine which interventions are effective in improving occupational performance after stroke. Forty-six articles met the inclusion criteria and were examined. Interventions for the following impairments were reviewed: general cognitive deficits, executive dysfunction, apraxia, memory loss, attention deficits, visual field deficits (included because of their close relationship with neglect), and unilateral neglect. Evidence is available from a variety of clinical trials to guide interventions regarding general cognition, apraxia, and neglect. The evidence regarding interventions for executive dysfunction and memory loss is limited. There is insufficient evidence regarding impairments of attention and mixed evidence regarding interventions for visual field deficits. The effective interventions have some commonalities, including being performance focused, involving strategy training, and using a compensatory as opposed to a remediation approach. The implications of the findings for practice, research, and education are discussed.

Capture, learning, and classification of upper extremity movement primitives in healthy controls and stroke patients

There currently exist no practical tools to identify functional movements in the upper extremities (UEs). This absence has limited the precise therapeutic dosing of patients recovering from stroke. In this proof-of-principle study, we aimed to develop an accurate approach for classifying UE functional movement primitives, which comprise functional movements. Data were generated from inertial measurement units (IMUs) placed on upper body segments of older healthy individuals and chronic stroke patients. Subjects performed activities commonly trained during rehabilitation after stroke. Data processing involved the use of a sliding window to obtain statistical descriptors, and resulting features were processed by a Hidden Markov Model (HMM). The likelihoods of the states, resulting from the HMM, were segmented by a second sliding window and their averages were calculated. The final predictions were mapped to human functional movement primitives using a Logistic Regression algorithm. Algorithm performance was assessed with a leave-one-out analysis, which determined its sensitivity, specificity, and positive and negative predictive values for all classified primitives. In healthy control and stroke participants, our approach identified functional movement primitives embedded in training activities with, on average, 80% precision. This approach may support functional movement dosing in stroke rehabilitation.

The effect of body orientation on a point-to-point movement in healthy elderly persons

OBJECTIVE

Upper limb retraining during the early phases of neurological rehabilitation often involves having individuals practice reaching in body orientations that reduce the effect of gravity on various joint motions (e.g., shoulder flexion, elbow extension). However, the efficacy of these training techniques has not been determined. The purpose of this study was to determine the effects of reducing gravity through a change in body orientation from sitting to side-lying on the kinematics of a point-to-point movement in healthy elderly persons.

METHOD

Nine healthy, right-hand-dominant women 62 to 66 years of age pointed to a target in two different body orientations-sitting and side-lying. A 2-dimensional kinematic analysis of the movement was performed to compare the trajectory of the hand and the interjoint coordination under the two conditions.

RESULTS

Regardless of body orientation relative to gravity, participants produced straight hand paths and smooth, bell-shaped velocity profiles. However, they moved slower in side-lying, and the pattern of interjoint coordination varied. The shoulder and elbow moved less, whereas the scapula made a greater contribution to the overall movement. Furthermore, the temporal coordination of the joints was modified as a consequence of body position.

CONCLUSION

The results indicate that point-to-point arm movements made against gravity differ from those made in a gravity-reduced plane, particularly at the joint level, illustrating that movement organization is sensitive to this contextual difference. The effect of minimizing gravity on upper limb movement needs to be explored in patient populations to determine whether training patients in gravity-reduced orientations is efficacious.

Using Mirror Therapy in the Home Environment: A Case Report

OBJECTIVE. Mirror therapy (MT) is a potential intervention to improve function after stroke. How to apply this intervention in practice is not clear. This case report illustrates the feasibility and effectiveness of a self-administered home-based MT program.

METHOD. A home-based MT program was practiced over 5 wk. The participant was encouraged to use MT for 30 min 5×/wk. Therapist contact occurred 1×/wk to monitor performance. An independent evaluator administered three outcome measures pre- and postintervention: Upper Extremity Sensory and Pain sections of the Fugl-Meyer Assessment; Jebsen–Taylor Test of Hand Function, and the Manual Ability Measure–20.

RESULTS. The participant engaged in a mean of 39.23 (±7.44) min of MT per day and used a variety of the recommended activities. Change scores indicated improvement on all of the included outcome measures.

CONCLUSION. This case report suggests that a predominantly self-administered home-based MT program is feasible and effective at improving function after stroke.

Motor imagery modality in expert dancers: an investigation of hip and pelvis kinematics in demi-plié and sauté

Elite dancers often engage in mental practice during training, but little is known about the effects of discrete, repetitive motor imagery on dance movement performance. This study compared the effects of two motor imagery modalities, third-person visual imagery and kinesthetic imagery, on hip and pelvis kinematics during two technical dance movements, plié and sauté. Twenty-four female dancers (mean age: 26.04; mean years of training: 19.63) were randomly assigned to a type of imagery practice: visual imagery (VI), kinesthetic imagery (KI), or a mental arithmetic task control condition (MAT). No statistically significant effects of imagery group or task type were found for external hip rotation, sagittal pelvic excursion, or a ratio relating hip to pelvic movement, suggesting that imagery practice did not affect either temporal or kinematic characteristics of the plié or sauté.

The Pragmatic Classification of Upper Extremity Motion in Neurological Patients: A Primer

Recent advances in wearable sensor technology and machine learning (ML) have allowed for the seamless and objective study of human motion in clinical applications, including Parkinson's disease, and stroke. Using ML to identify salient patterns in sensor data has the potential for widespread application in neurological disorders, so understanding how to develop this approach for one's area of inquiry is vital. We previously proposed an approach that combined wearable inertial measurement units (IMUs) and ML to classify motions made by stroke patients. However, our approach had computational and practical limitations. We address these limitations here in the form of a primer, presenting how to optimize a sensor-ML approach for clinical implementation. First, we demonstrate how to identify the ML algorithm that maximizes classification performance and pragmatic implementation. Second, we demonstrate how to identify the motion capture approach that maximizes classification performance but reduces cost. We used previously collected motion data from chronic stroke patients wearing off-the-shelf IMUs during a rehabilitation-like activity. To identify the optimal ML algorithm, we compared the classification performance, computational complexity, and tuning requirements of four off-the-shelf algorithms. To identify the optimal motion capture approach, we compared the classification performance of various sensor configurations (number and location on the body) and sensor type (IMUs vs. accelerometers). Of the algorithms tested, linear discriminant analysis had the highest classification performance, low computational complexity, and modest tuning requirements. Of the sensor configurations tested, seven sensors on the paretic arm and trunk led to the highest classification performance, and IMUs outperformed accelerometers. Overall, we present a refined sensor-ML approach that maximizes both classification performance and pragmatic implementation. In addition, with this primer, we showcase important considerations for appraising off-the-shelf algorithms and sensors for quantitative motion assessment.

Occupational Therapy Interventions for Adults With Stroke

Evidence Connection articles provide a clinical application of systematic reviews developed in conjunction with the American Occupational Therapy Association's (AOTA's) Evidence-Based Practice project. The clinical condition discussed in this inaugural Evidence Connection article is adults with stroke. Findings from the systematic reviews on this topic were published in the January/February 2015 issue of the American Journal of Occupational Therapy and in AOTA's Occupational Therapy Practice Guidelines for Adults With Stroke (Wolf & Nilsen, 2015). Each article in this series will summarize the evidence from the published reviews on a given topic and presents an application of the evidence to a related clinical case. Evidence Connection articles illustrate how the research evidence from the reviews can be used to inform and guide clinical decision making.

Thumb Stabilization and Assistance in a Robotic Hand Orthosis for Post-Stroke Hemiparesis

We propose a dual-cable method of stabilizing the thumb in the context of a hand orthosis designed for individuals with upper extremity hemiparesis after stroke. This cable network adds opposition/reposition capabilities to the thumb, and increases the likelihood of forming a hand pose that can successfully manipulate objects. In addition to a passive-thumb version (where both cables are of fixed length), our approach also allows for a single-actuator active-thumb version (where the extension cable is actuated while the abductor remains passive), which allows a range of motion intended to facilitate creating and maintaining grasps. We performed experiments with five chronic stroke survivors consisting of unimanual resistive-pull tasks and bimanual twisting tasks with simulated real-world objects; these explored the effects of thumb assistance on grasp stability and functional range of motion. Our results show that both active- and passive-thumb versions achieved similar performance in terms of improving grasp force generation over a no-device baseline, but active thumb stabilization enabled users to maintain grasps for longer durations.

Home mirror therapy: a randomized controlled pilot study comparing unimanual and bimanual mirror therapy for improved arm and hand function post-stroke

PURPOSE

To compare home-based unimanual mirror therapy (UMT) and bimanual mirror therapy (BMT) for upper limb recovery in subacute/chronic stroke individuals with moderate-to-severe arm impairment.

METHOD

Twenty-two participants were randomized into 1 of 3 groups: UMT, BMT or traditional occupational therapy (TOT) home-based programs. The intervention was 6-weeks and consisted of OT 2 days a week, weekly sessions with the research OT, and 30-minutes of the home-based program 5 days a week, according to group allocation. The Action Research Arm Test (ARAT), ABILHAND, Fugl-Meyer Assessment (FMA), grip strength, and Stroke Impact Scale (SIS) were used for outcome measures.

RESULTS

All groups significantly improved over time on all outcome measures and adhered to the prescribed dosage regardless of group (p<0.05). While there were no between-group differences, effect size and 95% confidence interval data suggest a clinical significance in favor of UMT as compared to the other groups.

CONCLUSIONS

All participants, regardless of home-based program, adhered to the prescribed dosage and significantly improved over time. Despite no between-group differences, effect size and 95% confidence interval data suggest that UMT may be more beneficial for individuals with moderate-to-severe arm impairment as compared to BMT or TOT. ClinicalTrials.gov: #NCT02780440Implications for RehabilitationHome-based unimanual mirror therapy (UMT), bimanual mirror therapy (BMT), and traditional occupational therapy (TOT), when administered in conjunction with outpatient OT, are helpful for improving upper limb recovery post-stroke.Home-based UMT may be more beneficial than BMT or TOT for improvement in upper limb motor function and activities of daily living of patients with moderate to severe arm impairment post-stroke.

Task Oriented Training Interventions for Adults With Stroke to Improve ADL and Functional Mobility Performance (2012-2019)

Systematic Review Briefs provide a summary of the findings from systematic reviews developed in conjunction with the American Occupational Therapy Association's Evidence-Based Practice Program. Each Systematic Review Brief summarizes the evidence on a theme related to a systematic review topic. This Systematic Review Brief presents findings from the systematic review on interventions to improve activities of daily living (ADL) and functional mobility performance for people with stroke. This theme reports on task-oriented training interventions.

Task-Oriented Training With Cognitive Strategies for Adults With Stroke to Improve ADL and/or Functional Mobility Performance (2012-2019)

Systematic Review Briefs provide a summary of the findings from systematic reviews developed in conjunction with the American Occupational Therapy Association's Evidence-Based Practice Program. Each Systematic Review Brief summarizes the evidence on a theme related to a systematic review topic. This Systematic Review Brief presents findings from the systematic review on interventions to improve activities of daily living and functional mobility performance for people with stroke. This theme reports on task-oriented training with cognitive strategies.

ChatEMG: Synthetic Data Generation to Control a Robotic Hand Orthosis for Stroke

Intent inferral on a hand orthosis for stroke patients is challenging due to the difficulty of data collection. Additionally, EMG signals exhibit significant variations across different conditions, sessions, and subjects, making it hard for classifiers to generalize. Traditional approaches require a large labeled dataset from the new condition, session, or subject to train intent classifiers; however, this data collection process is burdensome and time-consuming. In this paper, we propose ChatEMG, an autoregressive generative model that can generate synthetic EMG signals conditioned on prompts (i.e., a given sequence of EMG signals). ChatEMG enables us to collect only a small dataset from the new condition, session, or subject and expand it with synthetic samples conditioned on prompts from this new context. ChatEMG leverages a vast repository of previous data via generative training while still remaining context-specific via prompting. Our experiments show that these synthetic samples are classifier-agnostic and can improve intent inferral accuracy for different types of classifiers. We demonstrate that our complete approach can be integrated into a single patient session, including the use of the classifier for functional orthosis-assisted tasks. To the best of our knowledge, this is the first time an intent classifier trained partially on synthetic data has been deployed for functional control of an orthosis by a stroke survivor.

Effectiveness of Task-Oriented Approaches and Occupation-Based Activities to Improve Performance and Participation in Instrumental Activities of Daily Living (IADL) Among Adult Stroke Survivors (2009-2019)

Systematic Review Briefs provide a summary of the findings from systematic reviews developed in conjunction with the American Occupational Therapy Association's Evidence-Based Practice Program. Each Systematic Review Brief summarizes the evidence on a theme related to a systematic review topic. This Systematic Review Brief presents findings for task-oriented/occupation-based approaches and augmenting task-oriented training with cognitive strategies to support performance in instrumental activities of daily living among adult stroke survivors.