Central nervous system (CNS) injuries, including stroke, traumatic brain injury, and spinal cord injury, are leading causes of long-term disability. It is estimated that more than half of the survivors of severe unilateral injury are unable to use the denervated limb. Previous studies have focused on neuroprotective interventions in the affected hemisphere to limit brain lesions and neurorepair measures to promote recovery. However, the ability to increase plasticity in the injured brain is restricted and difficult to improve. Therefore, over several decades, researchers have been prompted to enhance the compensation by the unaffected hemisphere. Animal experiments have revealed that regrowth of ipsilateral descending fibers from the unaffected hemisphere to denervated motor neurons plays a significant role in the restoration of motor function. In addition, several clinical treatments have been designed to restore ipsilateral motor control, including brain stimulation, nerve transfer surgery, and brain-computer interface systems. Here, we comprehensively review the neural mechanisms as well as translational applications of ipsilateral motor control upon rehabilitation after CNS injuries.
Animals ; Spinal Cord Injuries/therapy* ; Motor Neurons/physiology* ; Brain ; Stroke ; Recovery of Function/physiology*

BACKGROUNDDepression is a common problem impeding post-stroke rehabilitation. Up to 70% of patients show depression symptoms during the first twelve months after stroke onset. However, the depression and its effect on functional recovery can be difficult to diagnose. The purpose of this study was to use gait analysis as a tool to compare the recovery after stroke in patients with and without depression and to assess the impact of the initiation time of rehabilitation after stroke onset.

METHODSOne hundred and forty five consecutive patients after first ever stroke admitted for designed rehabilitation program within 2 to 31 months after stroke onset participated. All patients received 4 weeks treatment program included comprehensive rehabilitation consisted of multipurpose activities 5 days a week. These included individual and group exercises, physiotherapy, occupational therapy and gait training. Gait analysis with Kistler force plates was employed to assess gait pattern symmetry before and after the treatment. Gait symmetry was evaluated based on seven gait parameters. Regaining of gait pattern symmetry was assumed as a measure of rehabilitation outcome.

RESULTSAfter rehabilitation program gait symmetry was regained in patients without depression. Gait asymmetry remained unchanged in patients diagnosed with depression. No major differences in outcome from rehabilitation were noted in regards to the initiation time of rehabilitation after the stroke onset.

CONCLUSIONSDepression limits gait recovery after stroke. The time of initiation of rehabilitation after stroke onset does not limit the motor recovery after rehabilitation program.

Adult ; Aged ; Depression ; physiopathology ; Female ; Gait ; physiology ; Humans ; Male ; Middle Aged ; Recovery of Function ; physiology ; Stroke ; physiopathology ; psychology ; Walking ; physiology

The aim of this study was to follow up the changes in the number of motor units according to the Brunnstrom stage through a motor unit number estimation of the Fwave (F-MUNE) after a stroke, and to identify the functional significance of F-MUNE. Twenty-five patients (15 men, 10 women) with a first unilateral stroke were recruited. The maximal M-potential was evoked by the supramaximal stimulation of the median nerve at the wrist, and the maximal stimulation intensity was determined on both hemiplegic and unaffected hands. The reproducible all-or-none F-wave was evoked in 30% of the maximal stimulation intensity and was constantly stimulated at that level. The prototypes of the F-wave were chosen, and the values of F-MUNE were calculated by dividing the amplitude of the maximal M-potential by the mean amplitude of the F-prototype. The changes in F-MUNE were compared according to the progression of the Brunnstrom stage and correlated with those of the functional scales. The mean motor unit numbers decreased significantly in the hemiplegic side compared with the unaffected side. According to the progression of the Brunnstrom stage, the values of F-MUNE were reduced significantly by increasing the amplitude and recruitment of the F-prototype, and the functional scores also improved. These results show that the F-MUNE equation did not show a functional recoveryrelated increase in stroke patients.
Aged ; Female ; Humans ; Male ; Middle Aged ; Motor Neurons/*physiology ; Prospective Studies ; *Recovery of Function ; Stroke/*physiopathology

There is close relationship between the morphologic changes of peripheral nerve after injury and its function recovery during regeneration. In our experiment, the sciatic nerve of rats was transected and bridge-connected with silicone tube, and the images of serial slices of different time and different injury parts were taken by micro-photograph system. The volume unit model was applied to rendering the three dimensional (3D) structure of degenerative and regenerative sciatic nerve fiber and its affiliated structure after injury. The 3D images showed that node of Ranvier had not formed and its array was turbulent, both the myelin sheath and the axis-cylinder were thinner, and the collagen fibres had proliferated.
Animals ; Male ; Nerve Regeneration ; physiology ; Rats ; Rats, Wistar ; Recovery of Function ; Sciatic Nerve ; injuries ; pathology ; physiopathology

Spinal cord injury (SCI) disrupts the structural and functional connectivity between the higher center and the spinal cord, resulting in severe motor, sensory, and autonomic dysfunction with a variety of complications. The pathophysiology of SCI is complicated and multifaceted, and thus individual treatments acting on a specific aspect or process are inadequate to elicit neuronal regeneration and functional recovery after SCI. Combinatory strategies targeting multiple aspects of SCI pathology have achieved greater beneficial effects than individual therapy alone. Although many problems and challenges remain, the encouraging outcomes that have been achieved in preclinical models offer a promising foothold for the development of novel clinical strategies to treat SCI. In this review, we characterize the mechanisms underlying axon regeneration of adult neurons and summarize recent advances in facilitating functional recovery following SCI at both the acute and chronic stages. In addition, we analyze the current status, remaining problems, and realistic challenges towards clinical translation. Finally, we consider the future of SCI treatment and provide insights into how to narrow the translational gap that currently exists between preclinical studies and clinical practice. Going forward, clinical trials should emphasize multidisciplinary conversation and cooperation to identify optimal combinatorial approaches to maximize therapeutic benefit in humans with SCI.
Humans ; Axons/pathology* ; Nerve Regeneration/physiology* ; Spinal Cord Injuries/therapy* ; Neurons/pathology* ; Recovery of Function

Endothelial progenitor cells (EPCs) are immature endothelial cells which have the capacity to proliferate, migrate and differentiate into mature endothelial cells from bone marrow to the peripheral circulation. EPCs have been shown to participate in postnatal endothelial repair and neovascularization of ischemic organs, and have been used as a new source of seeded cells in vascular tissue engineering. In this review, we focus on the origin, identification, property and function of EPCs as well as their application in vascular tissue engineering.
Animals ; Blood Vessels ; physiopathology ; Endothelial Cells ; cytology ; physiology ; Endothelium, Vascular ; pathology ; physiology ; Humans ; Neovascularization, Physiologic ; physiology ; Recovery of Function ; physiology ; Stem Cells ; cytology ; physiology ; Tissue Engineering ; methods

OBJECTIVEPresent study aimed at further comprehensive functional, histomorphometrical and immunohistochemical assessment of peripheral nerve regeneration using rat sciatic nerve transection model.

METHODSThe 10-mm rat sciatic nerve gap was created in rats. In control group nerve stumps were sutured to adjacent muscle and in treatment group the gap was bridged using an inside-out vein graft. In sham-operated group the nerve was manipulated and left intact. All animals underwent walking track analysis test 4, 8, and 12 weeks after surgery. Subsequently, muscle mass measurement was performed to assess reenervation, histological examination to observe the sciatic nerve regeneration morphologically and immunohistochemistry to detect Schwann cells using anti S-100. Results were analyzed using a factorial ANOVA with two between-subjects factors. Bonferroni test for pairwise comparisons was used to examine the effect of treatments.

RESULTSFunctional analysis of myelinated nerve fibers showed that nerve function improved significantly in the time course in treatment group. However, quantitative morphometrical analysis of myelinated nerve fibers showed that there was no significant difference between 8 and 12 weeks in treatment group. Muscle weight ratio was bigger and weight loss of the gastrocnemius muscle was ameliorated by inside-out vein grafting. The position of positive immunohistochemical reactions further implied that regenerated axons and Schwann cell-like cells existed after vein grafting was performed, and was accompanied by the process of myelination and structural recovery of regenerated nerves.

CONCLUSIONFunctional analysis of peripheral nerve repair is far more reliable than quantitative morphometrical analysis.

Animals ; Immunohistochemistry ; Male ; Nerve Regeneration ; Rats ; Recovery of Function ; S100 Proteins ; analysis ; Sciatic Nerve ; physiology ; surgery ; Veins ; transplantation

Electric field stimulation (EFS) can effectively inhibit local Ca ²⁺ influx and secondary injury after spinal cord injury (SCI). However, after the EFS, the Ca ²⁺ in the injured spinal cord restarts and subsequent biochemical reactions are stimulated, which affect the long-term effect of EFS. Polyethylene glycol (PEG) is a hydrophilic polymer material that can promote cell membrane fusion and repair damaged cell membranes. This article aims to study the combined effects of EFS and PEG on the treatment of SCI. Sprague-Dawley (SD) rats were subjected to SCI and then divided into control group (no treatment, n = 10), EFS group (EFS for 30 min, n = 10), PEG group (covered with 50% PEG gelatin sponge for 5 min, n = 10) and combination group (combined treatment of EFS and PEG, n = 10). The measurement of motor evoked potential (MEP), the motor behavior score and spinal cord section fast blue staining were performed at different times after SCI. Eight weeks after the operation, the results showed that the latency difference of MEP, the amplitude difference of MEP and the ratio of cavity area of spinal cords in the combination group were significantly lower than those of the control group, EFS group and PEG group. The motor function score and the ratio of residual nerve tissue area in the spinal cords of the combination group were significantly higher than those in the control group, EFS group and PEG group. The results suggest that the combined treatment can reduce the pathological damage and promote the recovery of motor function in rats after SCI, and the therapeutic effects are significantly better than those of EFS and PEG alone.
Animals ; Electric Stimulation ; Polyethylene Glycols/therapeutic use* ; Rats ; Rats, Sprague-Dawley ; Recovery of Function/physiology* ; Spinal Cord ; Spinal Cord Injuries/therapy*

OBJECTIVE: To summarize the research progress of stem cell transplantation in treating spinal cord injury (SCI) at different stages based on the pathophysiological mechanism of SCI. METHODS: The relevant research literature at home and abroad was extensively reviewed to explore the impact of transplantation timing on the effectiveness of stem cell transplantation in treating SCI. RESULTS: Researchers performed different types of stem cell transplantation for subjects at different stages of SCI through different transplantation approaches. Clinical trials have proved the safety and feasibility of stem cell transplantation at acute, subacute, and chronic stages, which can alleviate inflammation at the injured site and restore the function of the damaged nerve cells. But the reliable clinical trials comparing the effectiveness of stem cell transplantation at different stages of SCI are still lacking. CONCLUSION Stem cell transplantation has a good prospect in treating SCI. In the future, the multi-center, large sample randomized controlled clinical trials are needed, with a focus on the long-term effectiveness of stem cell transplantation.
Humans ; Hematopoietic Stem Cell Transplantation ; Neurons ; Recovery of Function/physiology* ; Spinal Cord ; Spinal Cord Injuries/surgery* ; Stem Cell Transplantation

OBJECTIVE: To determine the improvements of post-infarction heart function after transplantation of autologous skeletal myoblasts transfected with VEGF165 in rabbits. METHODS: Myocardium infarction was induced in rabbits by left anterior descending coronary artery ligation. At 2 weeks, 1.75×10(7) autologous skeletal myoblasts transfected with pcDNA3.1-VEGF165 were infused into the region of MI via direct intramuscular injection; pcDNA3.1 served as a control. RESULTS: The DAPI-labeled and Desmin-positive immunostained skeletal myofibers were found throughout the infracted areas and border zones, and the density of blood capillary in the MI region transplanted by myoblasts with VEGF165 was increased (measured 4 weeks later and compared with controls). Heart function was examined by the Buxco system and demonstrated that maximum dp/dt [(1607.23±102.67) mmHg/s vs (1217.77±89.91) mmHg/s] and minimum dp/dt [(-1535.09 ± 81.34) mmHg/s vs (1174.58 ± 91.5) mmHg/s] were improved in the heart transplanted with the transfected myoblasts(P<0.05). CONCLUSION Autologous skeletal myoblasts transfected with VEGF165 could ameliorate the blood supply in the MI region, and aid recovery of heart function more quickly in post-infarction hearts. This suggests an effective treatment for myocardium infarction.
Animals ; Female ; Myoblasts, Skeletal ; metabolism ; transplantation ; Myocardial Infarction ; physiopathology ; therapy ; Rabbits ; Recovery of Function ; Transfection ; Transplantation, Autologous ; Vascular Endothelial Growth Factor A ; genetics ; metabolism ; Ventricular Function, Left ; physiology