Electrical Stimulation Research Articles

Neuromuscular Electrical Stimulation And Heat Therapy Modalities On Recovery After Exercise-Induced Muscle Fatigue

Neuromuscular Electrical Stimulation And Heat Therapy Modalities On Recovery After Exercise-Induced Muscle Fatigue

Structure Activity Optimization of Ryanodine Receptor Modulators for the Treatment of Catecholaminergic Polymorphic Ventricular Tachycardia

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia disorder associated with potentially lethal arrhythmias. Most CPVT cases are caused by inherited variants in the ryanodine receptor type-2 (RYR2) gene. To investigate the structure activity relationship of tetracaine derivatives and test a lead compound in a mouse model of CPVT. We synthesized >200 tetracaine derivatives and characterized 11 of those. The effects of these compounds on Ca2+ handling in cardiomyocytes from R176Q/+ mice was tested using confocal microscopy. The effects of lead compound MSV1302 on arrhythmia inducibility and cardiac contractility were tested using programmed electrical stimulation and echocardiography, respectively. Plasma and microsomal stability and cytotoxicity assays were also performed. Ca2+ imaging revealed that 4 of 11 compounds suppressed sarcoplasmic reticulum Ca2+ leak through mutant RyR2. Two compounds selected for further testing exhibited an EC50 of 146 nM (MSV1302) and 49 nM (MSV1406), respectively. While neither compound altered baseline ECG intervals, only MSV1302 suppressed stress- and pacing-induced ventricular tachycardia in vivo in R176Q/+ mice. Echocardiography revealed that the lead compound MSV1302 did not negatively impact cardiac inotropy and chronotropy. Finally, compound MSV1302 did not block INa, ICa,L, or IKr, exhibited excellent stability in plasma and microsomes, and was not cytotoxic. Structure activity relationship studies of second generation tetracaine derivatives identified lead compound MSV1302 with a favorable pharmacokinetic profile. MSV1302 normalized aberrant RyR2 activity in vitro and in vivo, without altering cardiac inotropy, chronotropy or off-target effects on other ion channels. This compound may be a strong candidate for future clinical studies to determine its efficacy in CPVT patients.

The use of electrical stimulation to enhance recovery following peripheral nerve injury.

Peripheral nerve injury is common and can have devastating consequences. In severe cases, functional recovery is often poor despite surgery. This is primarily due to the exceedingly slow rate of nerve regeneration at only 1-3 mm/day. The local environment in the distal nerve stump supportive of nerve regrowth deteriorates over time and the target end organs become atrophic. To overcome these challenges, investigations into treatments capable of accelerating nerve regrowth are of great clinical relevance and are an active area of research. One intervention that has shown great promise is perioperative electrical stimulation. Postoperative stimulation helps to expedite the Wallerian degeneration process and reduces delays caused by staggered regeneration at the site of nerve injury. By contrast, preoperative "conditioning" stimulation increases the rate of nerve regrowth along the nerve trunk. Over the past two decades, a rich body of literature has emerged that provides molecular insights into the mechanism by which electrical stimulation impacts nerve regeneration. The end result is upregulation of regeneration-associated genes in the neuronal body and accelerated transport to the axon front for regrowth. The efficacy of brief electrical stimulation on patients with peripheral nerve injuries was demonstrated in a number of randomized controlled trials on compressive, transection and traction injuries. As approved equipment to deliver this treatment is becoming available, it may be feasible to deploy this novel treatment in a wide range of clinical settings.

Simplified discrete model for axisymmetric dielectric elastomer membranes with robotic applications

Soft robots utilizing inflatable dielectric membranes can realize intricate functionalities through the application of non-mechanical fields. However, given the current limitations in simulations, including low computational efficiency and difficulty in dealing with complex external interactions, the design and control of such soft robots often require trial and error. Thus, a novel one-dimensional (1D) discrete differential geometry (DDG)-based numerical model is developed for analyzing the highly nonlinear mechanics in axisymmetric inflatable dielectric membranes. The model captures the intricate dynamics of these membranes under both inflationary pressure and electrical stimulation. Comprehensive validations using hyperelastic benchmarks demonstrate the model’s accuracy and reliability. Additionally, the focus on the electro-mechanical coupling elucidates critical insights into the membrane’s behavior under varying internal pressures and electrical loads. The research further translates these findings into innovative soft robotic applications, including a spherical soft actuator, a soft circular fluid pump, and a soft toroidal gripper, where the snap-through of electroelastic membrane plays a crucial role. Our analyses reveal that the functional ranges of soft robots are amplified by the snap-through of an electroelastic membrane upon electrical stimuli. This study underscores the potential of DDG-based simulations to advance the understanding of the nonlinear mechanics of electroelastic membranes and guide the design of electroelastic actuators in soft robotics applications.

Somatosensory stimulation on the wrist enhances the subsequent hand-choice by biasing toward the stimulated hand.

Hand choice is an unconscious decision frequently made in daily life. The electroencephalogram before target presentation correlates with hand choice for the target where hand choice probability reaches equilibrium. However, whether neurophysiological interventions before target presentation influence hand choice remains unknown. Therefore, this study determined whether instantaneous somatosensory electrical stimulation administered to the unilateral wrist at 0, 300, or 600ms before the target presentation facilitates or inhibits stimulated hand choice for targets around the hand selection equilibrium point. A single electrical stimulation comprised five trains of 1ms electrical pulses, with a 20ms inter-pulse interval. The stimulus intensity was set at 80% of the motor threshold. This study included 14 right-handed healthy adults (five females and nine males; mean age, 25.1 ± 4.64years). Unilateral wrist stimulation significantly increased the probability of choosing the stimulated hand and led to a faster reaction time than bilateral wrist stimulation and no-stimulation conditions. The results suggest that prior somatosensory stimulation significantly affects the hand-choice process, effectively promoting the selection of the stimulated hand. These findings highlight the potential application of this stimulation method in stroke rehabilitation to facilitate the use of the paretic hand.

An Electrolyte‐Gated InGaZnO Phototransistor that Emulates Visual Experience‐Dependent Plasticity

AbstractInspired by neurobiological learning rules, bionic devices that simulate the fundamental functions of synapses and neurons provide a highly effective approach to neuromorphic computing. Among various learning rules, the Bienenstock‐Cooper‐Munro (BCM) learning rule can explain the threshold sliding effect of synaptic weight modification in the visual cortex, which is difficult to explain with the classical Hebb's rule. Existing research mainly focuses on exploiting electrical stimulation to implement the BCM rule, while the optical implementation is still unexplored. In this paper, the light‐history‐dependent BCM learning rule is implemented with electrolyte‐gated InGaZnO (IGZO) transistors. The channel conductance can be modulated through light illumination and electrical stimulation. By utilizing the light‐history‐dependent property of the IGZO electrolyte‐gated transistor and following the triplet‐spike‐timing‐dependent plasticity (STDP) rules, the BCM learning rule is successfully emulated in a single device. Moreover, the light‐history‐dependent property enables a variety of bionic vision functions including image edge detection and associative memory. This work provides a paradigm for the novel implementation of the BCM rule and paves the way for further development of machine vision systems.

Application of Transcutaneous Electrical Nerve Stimulation (TENS) in Stroke Rehabilitation: An Umbrella Review

Application of Transcutaneous Electrical Nerve Stimulation (TENS) in Stroke Rehabilitation: An Umbrella Review

Spared ulnar nerve injury results in increased layer III–VI excitability in the pig somatosensory cortex

This study describes cortical recordings in a large animal nerve injury model. We investigated differences in primary somatosensory cortex (S1) hyperexcitability when stimulating injured and uninjured nerves and how different cortical layers contribute to S1 hyperexcitability after spared ulnar nerve injury. We used a multielectrode array to record single-neuron activity in the S1 of ten female Danish landrace pigs. Electrical stimulation of the injured and uninjured nerve evoked brain activity up to 3 h after injury. The peak amplitude and latency of early and late peristimulus time histogram responses were extracted for statistical analysis. Histological investigations determined the layer of the cortex in which each electrode contact was placed. Nerve injury increased the early peak amplitude compared with that of the control group. This difference was significant immediately after nerve injury when the uninjured nerve was stimulated, while it was delayed for the injured nerve. The amplitude of the early peak was increased in layers III–VI after nerve injury compared with the control. In layer III, S1 excitability was also increased compared with preinjury for the early peak. Furthermore, the late peak was significantly larger in layer III than in the other layers in the intervention and control group before and after injury. Thus, the most prominent increase in excitability occurred in layer III, which is responsible for the gain modulation of cortical output through layer V. Therefore, layer III neurons seem to have an important role in altered brain excitability after nerve injury.

Comparing the effects of functional electrical stimulation with different frequencies and time duration to improve lower extremity muscle strength, gait, balance, posture control and quality of life among stroke patients

Comparing the effects of functional electrical stimulation with different frequencies and time duration to improve lower extremity muscle strength, gait, balance, posture control and quality of life among stroke patients

Effect of easy cupping combined with pelvic floor electrical stimulation and Kegel exercise and pelvic floor muscle surface electromyography on symptoms improvement in women with stress urinary incontinence.

This study aimed to evaluate the effectiveness of easy cupping combined with pelvic floor electrical stimulation and Kegel exercises in treating female patients with stress urinary incontinence (SUI). Ninety SUI patients were randomly assigned to two groups: the control group (pelvic floor electrical stimulation + Kegel exercises) and the experimental group (easy cupping + pelvic floor electrical stimulation + Kegel exercises). Outcomes assessed included pelvic floor muscle strength, urinary incontinence, urinary leakage, pelvic floor muscle surface electromyography, adverse effects, and patient satisfaction before and after treatment. Results showed significant improvements in pelvic floor muscle strength, International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICI-Q-SF) scores, and urinary leakage in both groups, with the experimental group showing greater improvements (P < 0.05). The experimental group also had higher pelvic floor muscle potential values and a greater total effective rate (P < 0.05). No significant differences in adverse effects were noted between groups, and patient satisfaction was higher in the experimental group (P < 0.05). In conclusion, the combination of easy cupping with pelvic floor electrical stimulation and Kegel exercises effectively enhances pelvic floor muscle strength, reduces urinary leakage, and improves patient satisfaction in women with stress urinary incontinence.

Impact of Pulse Electric Field Stimulation on Negative Air Ion Release Capacity of Snake Plants

To investigate the effects of pulse electric field stimulation on the photosynthetic electron transport chain and negative air ion (NAI) release capacity of snake plants, the chlorophyll content, fluorescence induction kinetics curve (OJIP curve), chlorophyll fluorescence parameters, and NAI release concentration of snake plants kept under identical greenhouse conditions under different pulse electric field stimulations were compared and analyzed. The experimental results show that (1) after pulse electric field stimulation, the chlorophyll content in treatment group T1 (5 kv) and T2 (7 kv) of snake plants increased by 6.30% and 6.70%, respectively, with significant differences observed between the two treatment groups and the control group (CK). (2) In both treatment groups, the OJIP curve exhibited higher values for the inflection point (I) and peak (P) compared to the origin (O) and inflection point (J) values, with the rising trend in the I–P segment being more gentle than that of the O–J segment. Additionally, the J band was above 0, with the peak value in the T2 group being higher than that in the T1 group. (3) The chlorophyll fluorescence parameters showed fluctuating variations. Specifically, Fm, TRo/CSo, ETo/CSo, and DIo/CSo showed ascending trends in the treatment groups. Fv/Fo, Sm, and ABS/RC exhibited descending trends; Fv/Fm, Vj, ETo/RC, and φEo showed relatively minor changes. The PIabs displayed a decreasing trend. The PItotal in the CK was greater than that in the T1 and T2 groups. (4) After 4 h of pulse electric field stimulation, the NAI concentration increased by 87.60% in the T1 group and by 62.09% in the T2 group, compared to the same measurement taken at 3 h. Pulse electric field impacts the photosynthetic electron transport chain of snake plants, thereby influencing their NAI release capacity. This study aims to elucidate the physiological responses of the chloroplasts in snake plants to pulsed electric field stimulation and to lay the foundation for enhancing the plant’s release of negative air ion concentrations through physical and technological means.

Transcutaneous Electrical Acupoint Stimulation for Elders with Amnestic Mild Cognitive Impairment: A Randomized Controlled Pilot and Feasibility Trial

Background: Amnestic mild cognitive impairment (aMCI) is an important window of opportunity for early intervention and rehabilitation in dementia. The aim of this study was to investigate the feasibility and effect of delivering transcutaneous electrical acupuncture stimulation (TEAS) intervention to elders with aMCI. Methods: A total of 61 aMCI patients were randomly allocated into the intervention group (receiving a 12-week TEAS) and control group (receiving health education). The feasibility outcomes included recruitment rate, retention rate, adherence rate, and an exploration of patients’ views and suggestions on the research. The effective outcomes included cognitive function, sleep quality, and life quality, which were measured by the Montreal cognitive assessment scale (MoCA), auditory verbal learning test—Huashan version (AVLT-H), Pittsburgh sleep quality index (PSQI), and quality of life short-term-12 (QoL SF-12). Results: The recruitment rate, retention rate, and adherence rate were 67.35%, 92.42%, and 85.29%, respectively. Most aspects of the research design and administration of the TEAS intervention were acceptable. The quantitative analysis suggests that compared with the control group, the scores of MoCA, AVLT-H, and SF-12 (mental component summary) were significantly better (p &lt; 0.05); however, the differences were not statistically significant in PSQI and SF-12 (physical component summary) (p &gt; 0.05). Conclusions: The findings demonstrated that the study was feasible. TEAS awas possible for enhancing cognitive function and mental health in people with aMCI.

Electro-Stimulation System with Artificial-Intelligence-Based Auricular-Triggered Algorithm to Support Facial Movements in Peripheral Facial Palsy: A Simulation Pilot Study

Background: Facial palsy causes severe functional disorders and impairs quality of life. Disturbing challenges for patients with acute facial palsy, but also with those with chronic facial palsy with synkinesis, are the loss of the ability to smile and insufficient eyelid closure. A potential treatment for these conditions could be a closed-loop electro-stimulation system that stimulates the facial muscles on the paretic side as needed to elicit eye closure, eye blink and smile in a manner similar to the healthy side. Methods: This study focuses on the development and evaluation of such a system. An artificial intelligence (AI)-based auricular-triggered algorithm is used to classify the intended facial movements. This classification is based on surface electromyography (EMG) recordings of the extrinsic auricular muscles, specifically the anterior, superior, and posterior auricular muscle on the paretic side. The system then delivers targeted surface electrical stimulation to contract the appropriate facial muscles. Results: The evaluation of the system was conducted with 17 patients with facial synkinesis, who performed various facial movements according to a paradigm video. The system’s performance was evaluated through a simulation, using previously captured data as the inputs. The performance was evaluated by means of the median macro F1-score, which was calculated based on the stimulation signal (output of the system) and the actual movements the patients performed. Conclusions: This study showed that such a system, using an AI-based auricular-triggered algorithm, can support with a median macro F1-score of 0.602 for the facial movements on the synkinetic side in patients with unilateral chronic facial palsy with synkinesis.

Systematic narrative review of modalities in physiotherapy for managing pain in hip and knee osteoarthritis: A review.

Osteoarthritis (OA) affects 528 million individuals globally, predominantly in knee and hip joints, with a notable impact on females aged over 55, resulting in a substantial economic burden. However, the efficacy of modalities used in physiotherapy to manage OA pain for reducing the need for joint replacement remains an open question, and guidelines differ. Our systematic narrative review, drawing from reputable databases (e.g., PubMed, Cochrane, and CINAHL) with specific Mesh terms investigated evidence from 23 Randomized Controlled Trials (that included a control or a sham group in 30 different protocols) using therapeutic modalities like ultrasound, diathermy, and electrical stimulation for knee and hip OA pain, involving a total of 1055 subjects. We investigated the attainment of minimal clinically important differences in pain reduction, operationalized through a 20% decrement in the Western Ontario and McMaster University Arthritis Index or Visual Analog Scale (VAS) score. Our results indicated that 15 protocols out of 30 reach that level, but there were no statistical differences among modalities. Half of the protocol presented in the literature reached clinical efficiency but studies on hip remains scarce. We recommend a comprehensive, sequential, and multimodal intervention plan for individuals with joint OA with initial transcutaneous electrical nerve stimulation and progressing to a 2-week protocol of continuous ultrasound, potentially combined with deep microwave diathermy. Long-term intervention involves the use of pulsed electrical stimulation. For hip OA, a cautious approach and discussions with healthcare providers about potential benefits of spinal cord nerve stimulation.

Does Combined Electrical Muscle Stimulation on Gastrocnemius Muscle Training Improve Neuromuscular Response and Sports Performance?

Does Combined Electrical Muscle Stimulation on Gastrocnemius Muscle Training Improve Neuromuscular Response and Sports Performance?

The interaction between neutrophils and atrial myocytes in the occurrence and development of atrial fibrillation

BackgroundAtrial fibrillation (AF) is one of the most prevalent sustained cardiac arrhythmias, strongly associated with neutrophils. However, the underlying mechanism remain unclear. This study aims to explore the interaction between neutrophils and atrial myocytes in the pathogenesis of AF.MethodsPatch-clamp was employed to record the action potential duration (APD) and ion channels in HL-1 cells. Flow cytometry was used to assess the differentiation of neutrophils. The mRNA and protein levels of CACNA1C, CACNA2D, and CACNB2 in HL-1 cells were detected.ResultsHigh-frequency electrical stimulation resulted in a shortening of the APD in HL-1 cells. Flow cytometry demonstrated that neutrophils were polarized into N1 phenotype when cultured with stimulated HL-1 cells medium. Compared to control neutrophils conditioned medium (CM), cocultured with TNF-α knockout neutrophils CM prolonged APD and the L-type Ca (2+) channel (LTCC) of HL-1 cells. Additionally, the expression of CACNA2D, CACNB2 and CACNA1C in HL-1 cells were upregulated. Compared with CACNA1C siRNA-transfected HL-1 cells treated with TNF-α siRNA-transfected neutrophils CM, the APD and LTCC of CACNA1C siRNA-transfected HL-1 cells were shortened in control N1 neutrophil CM. The APD and LTCC of control HL-1 cells were also shortened in control N1 neutrophil CM, but prolonged in TNF-α siRNA-transfected neutrophils CM.ConclusionThese findings suggest that neutrophils were polarized into N1 phenotype in AF, TNF-α released from N1 neutrophils contributes to the pathogenesis of AF, via decreasing the APD and LTCC in atrial myocytes through down-regulation of CACNA1C expression.

Artificial embodiment displaces cortical neuromagnetic somatosensory responses

Integrating artificial limbs as part of one's body involves complex neuroplastic changes resulting from various sensory inputs. While somatosensory feedback is crucial, plastic processes that enable embodiment remain unknown. We investigated this using somatosensory evoked fields (SEFs) in the primary somatosensory cortex (S1) following the Rubber Hand Illusion (RHI), known to quickly induce artificial limb embodiment. During electrical stimulation of the little finger and thumb, 19 adults underwent neuromagnetic recordings before and after the RHI. We found early SEF displacement, including an illusion-brain correlation between extent of embodiment and specific changes to the first cortical response at 20 ms in Area 3b, within S1. Furthermore, we observed a posteriorly directed displacement at 35 ms towards Area 1, known to be important for visual integration during touch perception. That this second displacement was unrelated to extent of embodiment implies a functional distinction between neuroplastic changes of these components and areas. The earlier shift in Area 3b may shape extent of limb ownership, while subsequent displacement into Area 1 may relate to early visual-tactile integration that initiates embodiment. Here we provide evidence for multiple neuroplastic processes in S1—lasting beyond the illusion—supporting integration of artificial limbs like prostheses within the body representation.

The effect of brain-computer interface controlled functional electrical stimulation training on rehabilitation of upper limb after stroke: a systematic review and meta-analysis

The effect of brain-computer interface controlled functional electrical stimulation training on rehabilitation of upper limb after stroke: a systematic review and meta-analysis

Effect of Whole-Body Electrical Muscle Stimulation Training on Inflammatory and Anti-inflammatory Cytokines in Overweight Men.

The aim of this study was to investigate the effects of whole-body electrical muscle stimulation (WB-EMS) training on inflammatory and anti-inflammatory cytokines in overweight men. We divided 30 participants into EMS and control groups. The training program for the EMS group comprised 20 WB-EMS sessions (7 weeks, three sessions per week). The results showed that EMS training caused significant increase in interferon γ (P<0.001) and interleukin 10 (IL-10; P<0.01) and significant decrease in IL-17 and IL-23 (P<0.05). Also, the lipid profile showed significant positive changes in the EMS training group. EMS training, a novel exercise method that uses electric stimulation, can affect the levels of various cytokines that are involved in inflammation and immunity. EMS training can have both beneficial and harmful effects on the body depending on the type and balance of involved cytokines.

Electrically conductive functionalization of cured polyether ether ketone with improved bioactivity by surface-polymerization of polyaniline

The electrically conductive polyether ether ketone (PEEK) holds great promise for antibacterial and cell growth promotion under electrical stimulation, making it a promising material for next-generation implants. However, it is a significant challenge for electrically conductive functionalization of PEEK, especially for cured or shaped PEEK. In addition, PEEK’s bioactivity is still underdeveloped at present. Here, an electrically conductive PEEK with improved bioactivity is prepared through surface-polymerization of polyaniline (PANI) in the shell layer of cured PEEK. Impressively, an extremely high conductivity of 5.2 × 10−2 S/cm is achieved for the conductive PEEK among all the reported PANI/PEEK composites or blends with the optimal conductivity of 3.0 × 10−4 S/cm. It has been demonstrated that the conductive shell layer of the conductive PEEK features a PANI/PEEK semi-interpenetrating polymer network structure, explaining its conductivity. Improved cell proliferative activity is also disclosed for the conductive PEEK compared to that of the pure PEEK, and good biocompatibility and osteogenesis properties are further confirmed for the fabricated conductive PEEK scaffold. This conductive functionalization approach offers a significant advancement for developing next-generation biological implants and could be applied to other cured polymers as well.