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The value associated with reward is sensitive to external factors, such as the time between the choice and reward delivery as classically manipulated in temporal discounting tasks. Subjective preference for two reward options is dependent on objective variables of reward magnitude and reward delay. Single neuron correlates of reward value have been observed in regions, including ventral striatum, orbital, and medial prefrontal cortex. Brain imaging studies show cortico-striatal-limbic network activity related to subjective preferences. To explore how oscillatory dynamics represent reward processing across brain regions, we measured local field potentials of rats performing a temporal discounting task. Our goal was to use a data-driven approach to identify an electrophysiological marker that correlates with reward preference. We found that reward-locked oscillations at beta frequencies signaled the magnitude of reward and decayed with longer temporal delays. Electrodes in orbitofrontal/medial prefrontal cortex, anterior insula, ventral striatum, and amygdala individually increased power and were functionally connected at beta frequencies during reward outcome. Beta power during reward outcome correlated with subjective value as defined by a computational model fit to the discounting behavior. These data suggest that cortico-striatal beta oscillations are a reward signal correlated, which may represent subjective value and hold potential to serve as a biomarker and potential therapeutic target.

Muscle fiber conduction velocity (MFCV) can be affected by muscle fiber geometry at different joint angles and during joint movements. This study aimed to investigate MFCV during electrically evoked contraction at different joint angles, during joint movements, and during voluntary contractions. Sixteen healthy young men participated. A stimulation electrode was attached on the innervation zone of the vastus lateralis, and a linear electrode array was attached on the vastus lateralis. Under a static condition, electrically evoked electromyography signals were recorded at knee joint angles set every 15° between 0° and 105°. Under a passive movement condition, signals were recorded during knee extension and flexion passively. Under a voluntary contraction condition, signals were recorded while performing 30% or 60% of maximum voluntary contraction. MFCV was calculated using cross-correlation coefficients. Under the static condition, there were no differences in MFCV among various joint angles. Under the passive movement condition, MFCV was significantly greater during high velocity or shortening. Under the voluntary contraction condition, MFCV was significantly greater during high-intensity voluntary contraction and with a shortened muscle length. Joint angles do not influence MFCV markedly during relaxation, but it is possible to overestimate MFCV during movement or voluntary contraction. [ABSTRACT FROM AUTHOR]

Retinal prosthetics are one of the leading therapeutic strategies to restore lost vision in patients with retinitis pigmentosa and age-related macular degeneration. Much work has described patterns of spiking in retinal ganglion cells (RGCs) in response to electrical stimulation, but less work has examined the underlying retinal circuitry that is activated by electrical stimulation to drive these responses. Surprisingly, little is known about the role of inhibition in generating electrical responses or how inhibition might be altered during degeneration. Using whole-cell voltage-clamp recordings during subretinal electrical stimulation in the rd10 and wild-type (wt) retina, we found electrically evoked synaptic inputs differed between ON and OFF RGC populations, with ON cells receiving mostly excitation and OFF cells receiving mostly inhibition and very little excitation. We found that the inhibition of OFF bipolar cells limits excitation in OFF RGCs, and a majority of both pre- and postsynaptic inhibition in the OFF pathway arises from glycinergic amacrine cells, and the stimulation of the ON pathway contributes to inhibitory inputs to the RGC. We also show that this presynaptic inhibition in the OFF pathway is greater in the rd10 retina, compared with that in the wt retina.

Retinitis pigmentosa is a hereditary retinal disease that affects rod and cone photoreceptors, leading to progressive photoreceptor loss. Previous research supports the beneficial effect of electrical stimulation on photoreceptor survival. This study aims to identify the most effective electrical stimulation parameters and functional advantages of transcorneal electrical stimulation (tcES) in mice affected by inherited retinal degeneration. Additionally, the study seeked to analyze the electric field that reaches the retina in both eyes in mice and post-mortem humans. In this study, we recorded waveforms and voltages directed to the retina during transcorneal electrical stimulation in C57BL/6J mice using an intraocular needle probe with rectangular, sine, and ramp waveforms. To investigate the functional effects of electrical stimulation on photoreceptors, we used human retinal explant cultures and rhodopsin knockout (Rho–/–) mice, demonstrating progressive photoreceptor degeneration with age. Human retinal explants isolated from the donors' eyes were then subjected to electrical stimulation and cultured for 48 hours to simulate the neurodegenerative environment in vitro. Photoreceptor density was evaluated by rhodopsin immunolabeling. In vivo Rho–/– mice were subjected to two 5-day series of daily transcorneal electrical stimulation using rectangular and ramp waveforms. Retinal function and visual perception of mice were evaluated by electroretinography and optomotor response (OMR), respectively. Immunolabeling was used to assess the morphological and biochemical changes of the photoreceptor and bipolar cells in mouse retinas. Oscilloscope recordings indicated effective delivery of rectangular, sine, and ramp waveforms to the retina by transcorneal electrical stimulation, of which the ramp waveform required the lowest voltage. Evaluation of the total conductive resistance of the post-mortem human compared to the mouse eyes indicated higher cornea-to-retina resistance in human eyes. The temperature recordings during and after electrical stimulation indicated no significant temperature change in vivo and only a subtle temperature increase in vitro (~0.5–1.5°C). Electrical stimulation increased photoreceptor survival in human retinal explant cultures, particularly at the ramp waveform. Transcorneal electrical stimulation (rectangular + ramp) waveforms significantly improved the survival and function of S and M-cones and enhanced visual acuity based on the optomotor response results. Histology and immunolabeling demonstrated increased photoreceptor survival, improved outer nuclear layer thickness, and increased bipolar cell sprouting in Rho–/– mice. These results indicate that transcorneal electrical stimulation effectively delivers the electrical field to the retina, improves photoreceptor survival in both human and mouse retinas, and increases visual function in Rho–/– mice. Combined rectangular and ramp waveform stimulation can promote photoreceptor survival in a minimally invasive fashion. [ABSTRACT FROM AUTHOR]

Electrical stimulation (ES) of cellular systems can be utilized for biotechnological applications and electroceuticals (bioelectric medicine). Neural cell stimulation especially has a long history in neuroscience research and is increasingly applied for clinical therapies. Application of ES via conventional electrodes requires external connectors and power sources, hindering scientific and therapeutic applications. Here engineering novel 3D scaffold‐free human neural stem cell constructs with integrated piezoelectric nanoparticles for enhanced neural tissue induction and function is described. Tetragonal barium titanate (BaTi03) nanoparticles are employed as piezoelectric stimulators prepared as cytocompatible dispersions, incorporated into 3D self‐organizing neural spheroids, and activated wirelessly by ultrasound. Ultrasound delivery (low frequency; 40 kHz) is optimized for cell survival, and nanoparticle activation enabled ES throughout the spheroids during differentiation, tissue formation, and maturation. The resultant human neural tissues represent the first example of direct tissue loading with piezoelectric particles for ensuing 3D ultrasound‐mediated piezoelectric enhancement of human neuronal induction from stem cells, including augmented neuritogenesis and synaptogenesis. It is anticipated that the platform described will facilitate advanced tissue engineering and in vitro modeling of human neural (and potentially non‐neural) tissues, with modeling including tissue development and pathology, and applicable to preclinical testing and prototyping of both electroceuticals and pharmaceuticals. [ABSTRACT FROM AUTHOR]

AbstractObjectiveMethodsResultsConclusion\nIMPLICATIONS FOR REHABILITATIONComparing the efficacy of electrical stimulation (ES) and pelvic floor muscles training (PFMT) on urinary incontinence (UI) symptoms, quality of life and sexual function on women with stress UI. Also, to analyze the influence of supervised and non-supervised PFMT.Systematic review of randomized trials involving adult women with stress UI. Studies’ review was performed by two independent researchers on PubMed, EMBASE, PEDro, Cochrane Library, LILACS. The PEDro scale was used to evaluate the quality of included studies. The certainty of evidence was analyzed by the GRADE. A meta-analysis was performed.Seven studies comprising 411 women with stress UI were included. Methodological quality ranged from 3 to 8 points. Treatment sessions varied from 5 to 45 min (PMFT) and 15 to 30 min (ES), from 4 weeks to 6 months. Studies varied regarding the type of electrical current and its characteristics. With very low certainty of evidence and severe risk of methodological bias, the meta-analysis showed that ES is not superior to supervised or unsupervised PFMT for any outcome.ES is not superior to PFMT for reducing urinary leakage or improving quality of life in women with stress UI.Electrical stimulation and pelvic floor muscle training are widely used interventions in the treatment of urinary incontinenceRecommendations on the difference in the efficacy of electrical stimulation and pelvic floor muscles training in reducing UI symptoms in adult women need to be very cautious; up to now there is no evidence that show superiority between pelvic floor muscle training or electrical stimulationWe suggest that future research on this field be concerned regarding study design, methodologic quality and adequate number of subjects, since the studies included in this systematic review were heterogeneous regarding variables as main outcome and also the protocols both for the pelvic floor muscles training and the electrical stimulationElectrical stimulation and pelvic floor muscle training are widely used interventions in the treatment of urinary incontinenceRecommendations on the difference in the efficacy of electrical stimulation and pelvic floor muscles training in reducing UI symptoms in adult women need to be very cautious; up to now there is no evidence that show superiority between pelvic floor muscle training or electrical stimulationWe suggest that future research on this field be concerned regarding study design, methodologic quality and adequate number of subjects, since the studies included in this systematic review were heterogeneous regarding variables as main outcome and also the protocols both for the pelvic floor muscles training and the electrical stimulation [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) stands as a prevalent and detrimental arrhythmic disorder, characterized by intricate pathophysiological mechanisms. The availability of reliable and reproducible AF models is pivotal in unraveling the underlying mechanisms of this complex condition. Unfortunately, the researchers are still confronted with the absence of consistent in vitro AF models, hindering progress in this crucial area of research. Methods: Human induced pluripotent stem cells derived atrial myocytes (hiPSC-AMs) were generated based on the GiWi methods and were verified by whole-cell patch clamp, immunofluorescent staining, and flow cytometry. Then hiPSC-AMs were employed to establish the AF model by HS. Whole-cell patch clamp technique and calcium imaging were used to identify the AF model. The stability of 29 reference genes was evaluated using delta-Ct, GeNorm, NormFinder, and BestKeeper algorithms; Results: HiPSC-AMs displayed atrial myocyte action potentials and expressed the atrial-specific protein MLC-2 A and NR2F2, about 70% of the cardiomyocytes were MLC-2 A positive. After HS, hiPSC-AMs showed a significant increase in beating frequency, a shortened action potential duration, and increased calcium transient frequency. Of the 29 candidate genes, the top five most stably ranked genes were ABL1, RPL37A, POP4, RPL30, and EIF2B1. After normalization using ABL1, KCNJ2 was significantly upregulated in the AF model; Conclusions: In the hiPSC-AMs AF model established by HS, ABL1 provides greater normalization efficiency than commonly used GAPDH. [ABSTRACT FROM AUTHOR]

Kilohertz‐frequency alternating currents (KFACs) have been indicated to minimize muscle atrophy and weakness. However, the optimal stimulation parameters still need to be determined. Objective: This study aimed to investigate the effects of different KFACs on evoked torque, current efficiency, and perceived discomfort. Design: KFACs with frequencies of 1 kHz (Aussie current) and 2.5 kHz (Russian current), along with two duty cycles (10% and 20%), were randomly applied to the triceps surae muscle of healthy participants using a crossover design. The NMES intensity, NMES‐evoked torque, NMES efficiency, and NMES discomfort were measured in maximal and submaximal conditions. Statistical analyses were conducted using a two‐way mixed‐model ANOVA with repeated measures. Forty‐four participants were included. Results: Aussie currents produced higher evoked torque and efficiency in maximal and submaximal efforts, with higher perceived discomfort in maximal effort. Although the Australian current may cause greater discomfort at maximal efforts, it matches the Russian current in perceived discomfort at submaximal levels. The 20% duty cycle produced the highest efficiency in submaximal efforts. Conclusion: In both maximal and submaximal efforts, the Aussie current demonstrated superior NMES efficiency, yielding higher torque with lower amplitude than the Russian current. Clinicians should take these findings into consideration when prescribing KFACs to optimize clinical outcomes. [ABSTRACT FROM AUTHOR]

Piezoelectric nanomaterials for wireless neuromodulation is a promising alternative to traditional electrical stimulation. However, the low‐avidity between piezoelectric nanomaterials and cellular membranes leads to low efficiency of electrical signal transmission, which requires high‐intensity thresholds of ultrasound stimulation (US). Here, lead‐free piezoelectric (K,Na)NbO3 (KNN) nanoparticles (NPs) with cholesterol coating (KNNC) are presented, in which Cholesterol can be accommodated in the membrane and make them append on the plasma membrane. Compared to non‐modified nanoparticles, cell‐anchored KNNC NPs highly resist convective washout owing to high affinity of cholesterol to biological membranes, which enables highly efficient wireless electrical stimulation to activate cell impulses under low‐intensity ultrasound. Meanwhile, after perfusion washing, the KNNC NPs distributed around the cells are washed away, while part of KNNC NPs remain on the surface of cell membrane still can induce significant Ca2+ influx under US, similar to the group without washing, indicating the KNNC NPs appended on the cell play a major role in wireless electrical stimulation. Furthermore, the highly efficient electrical transmission of KNNC enables neural differentiation of stem cells in regulating synaptic plasticity by modulating Ca2+ influx, demonstrating that KNNC NPs offer a perspective toward minimally invasive wireless neuromodulation therapies for neurological diseases. [ABSTRACT FROM AUTHOR]

Biosyncretic robots composed of living and synthetic materials have garnered significant attention due to their high energy conversion efficiency, good biocompatibility and human‐robot interaction safety. Among common living actuation materials, artificial skeletal muscle tissue (ASMT) stands out for its good size scalability, controllability, and potential high driving force. However, due to the low differentiation efficiency of myoblasts, the performance of ASMT lags behind that of natural skeletal muscle tissue, thereby hindering the progress of biosyncretic robots. Here, inspired by the training mode of human skeletal muscle, an electromechanical co‐stimulation system for enhancing the performance of ASMTs is proposed. This system is capable of simultaneously applying electrical and mechanical stimulation to ASMTs. Moreover, the mechanical resistance can be dynamically adjusted during ASMT growth based on real‐time measurements of the contractile force of the ASMT. The results show that the enhanced ASMTs demonstrate improved differentiation and performance and can actuate a robot at a maximum speed of 2.38 mm s−1, which is faster than those of most currently reported ASMT‐based robots. This study introduces a novel approach for enhancing the performance of ASMTs, with substantial implications for the fields of biosyncretic robots and tissue engineering. [ABSTRACT FROM AUTHOR]

Objectives: The study objective was to investigate the influence of electrical stimulus properties on cervical and ocular vestibular‐evoked myogenic potentials to electrical stimulation by cochlear implants (e‐cVEMPs, e‐oVEMPs). Methods: E‐VEMPs were recorded in adult Nucleus cochlear implant (CI) patients using electric pulse trains (4 biphasic pulses at 1000 Hz burst rate). Ground path and stimulation electrodes were varied between monopolar stimulation at basal electrode contact E3 (MP1 + 2 E3), monopolar stimulation at apical electrode contact E20 (MP1 + 2 E20), and bipolar transmodiolar stimulation between E3 and E14 (BP E3‐E14). The electric pulse train was further varied to 2 pulses at 1000 Hz, 2 pulses at 500 Hz, and a single pulse, in patients with present e‐VEMP responses. VEMPs to bone‐conducted vibration (BCV) were recorded as reference in all participants. Results: Measurements were conducted in 30 ears of 27 participants (mean age 49.3 years, SD 12.7 years). E‐VEMPs were present in 13 ears (43%). 5 of the 13 cases showed e‐VEMPs but no BCV evoked VEMPs. Response numbers increased with increasing stimulation levels. The highest response rate of 40% was obtained for MP1 + 2 E3 stimulation. Stimulus variation did not affect response numbers. E‐VEMP amplitudes were comparable to BCV‐stimulated VEMPs. Latencies were up to 3.1 ms shorter for electric stimulation. Some patients showed e‐VEMP thresholds close to or below the electric hearing threshold level. Conclusion: The occurrence of e‐VEMPs is dependent on current path and stimulation level. Vestibular co‐stimulation by the CI is more likely in patients with high stimulation levels and for monopolar stimulation of basal electrode contacts. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

Therapeutic development for skeletal muscle diseases is challenged by a lack of ex vivo models that recapitulate human muscle physiology. Here, we engineered 3D human skeletal muscle tissue in the Biowire II platform that could be maintained and electrically stimulated long‐term. Increasing differentiation time enhanced myotube formation, modulated myogenic gene expression, and increased twitch and tetanic forces. When we mimicked exercise training by applying chronic electrical stimulation, the "exercised" skeletal muscle tissues showed increased myotube size and a contractility profile, fatigue resistance, and gene expression changes comparable to in vivo models of exercise training. Additionally, tissues also responded with expected physiological changes to known pharmacological treatment. To our knowledge, this is the first evidence of a human engineered 3D skeletal muscle tissue that recapitulates in vivo models of exercise. By recapitulating key features of human skeletal muscle, we demonstrated that the Biowire II platform may be used by the pharmaceutical industry as a model for identifying and optimizing therapeutic drug candidates that modulate skeletal muscle function. [ABSTRACT FROM AUTHOR]

Purpose: The involvement of central command in central hemodynamic regulation during exercise is relatively well-known, although its contribution to peripheral hemodynamics at the onset of low-intensity contractions is debated. This study sought to examine central and peripheral hemodynamics during electrically-evoked muscle contractions (without central command) and voluntary muscle activity (with central command). Methods: Cyclic quadriceps isometric contractions (1 every second), either electrically-evoked (ES; 200 ms trains composed of 20 square waves) or performed voluntarily (VC), were executed by 10 healthy males (26 ± 3 years). In both trials, matched for force output, peripheral and central hemodynamics were analysed. Results: At exercise onset, both ES and VC exhibited equal peaks of femoral blood flow (1276 ± 849 vs. 1117 ± 632 ml/min, p > 0.05) and vascular conductance (15 ± 11 vs. 13 ± 7 ml/min/mmHg, p > 0.05), respectively. Similar peaks of heart rate (86 ± 16 bpm vs. 85 ± 16 bpm), stroke volume (100 ± 20 vs. 99 ± 27 ml), cardiac output (8.2 ± 2.5 vs. 8.5 ± 2.1 L/min), and mean arterial pressure (113 ± 13 vs. 113 ± 3 mmHg), were recorded (all, p > 0.05). After ~ 50 s, all the variables drifted to lower values. Collectively, the hemodynamics showed equal responses. Conclusion: These results suggest a similar pathway for the initial (first 40 s) increase in central and peripheral hemodynamics. The parallel responses may suggest an initial minimal central command involvement during the onset of low-intensity contractions, likely associated with a neural drive activation delay or threshold. [ABSTRACT FROM AUTHOR]

Numerous associated challenges arise with the advancement and continuous improvement of implantable medical devices, such as the frequent requirement for battery replacement. The flexible ultrasonic‐induced wireless energy conversion (UWEC) technology has garnered significant interest due to its superior energy transmission efficiency, safety, and biocompatibility compared to traditional electromagnetic wireless energy conversion technology. This paper provides a comprehensive review of the recent advancements in two types of flexible UWEC technologies, triboelectric nanogenerators, and piezoelectret nanogenerators, with a focus on their applications in implantable medical treatments. First, the energy conversion principles and general materials of flexible UWEC are presented. Then, the research and application of flexible UWEC devices are introduced in detail based on their medical functions. At the end of this review, perspectives and opportunities are discussed. [ABSTRACT FROM AUTHOR]

Electrical stimulation has been integrated in recent decades into rehabilitation protocols following neuromuscular injuries. Existing literature supports the utilisation of prolonged or continuous stimulation generated by implantable or transcutaneous devices for chronic pain subsidence and muscle trophism maintenance, which improve outcomes following microsurgical interventions. Newer uses include brief electrical stimulation for peripheral nerve injury. Brief electrical stimulation has shown promise in expediting regeneration of both torn and crushed nerve axons in the murine model and has been incorporated into a limited number of clinical studies. Augmentation of the natural response of an injured peripheral nerve by electrical stimulation has the potential to accelerate regeneration, presumably leading to improved function and clinical outcomes. We review the existing literature on intraoperative utilisation of electrical stimulation to enhance regeneration, such as neural mechanisms of action and their microscopic effect in animal models, as well as results from initial human studies. Level of Evidence: Level V (Therapeutic) [ABSTRACT FROM AUTHOR]

Objective: This study investigated the effect of neuromuscular electrical stimulation on the frontal ankle motor control in individuals with chronic ankle instability during drop landing. Design: This was a randomized, controlled, double-blind trial. Thirtysix individuals with chronic ankle instability were randomly assigned to each group. Participants received 6-wk neuromuscular electrical stimulation intervention and sham stimulation in the neuromuscular electrical stimulation and control groups, respectively. Data were collected at week0 and week6. A mixed-effects model and analysis of covariance were employed to investigate the between-group differences in continuous and discrete outcome variables at week6, with the outcome variables at week0 as covariates. Results: Compared to control group, neuromuscular electrical stimulation group exhibited a 2.66° (2.45, 2.86) reduction in frontal ankle inversion angle, a 47.41°/sec (−16.05, −78.77) decrease in peak ankle inversion angular velocity, and a 0.43 Nm/kg (0.18, 0.68) increase in peak ankle eversion moment during drop landing at week6. Conclusions: Applying 6-wk neuromuscular electrical stimulation to the fibularis longus resulted in decreased ankle inversion angle and ankle inversion angular velocity and increased peak ankle eversion moment during drop landing. Consequently, neuromuscular electrical stimulation could be considered an effective modality for individuals with chronic ankle instability to enhance the frontal ankle movement patterns and overall ankle motor control. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spinal cord injury damages axons, causing loss of motor and sensory function. • Promoting and guiding axonal regrowth is essential for functional recovery. • 3D-printed, electroconductive scaffolds with tuneable geometries were developed. • Scaffolds were functionalised with aligned, neurotrophic extracellular matrix. • Electrostimulation via scaffolds significantly increased outgrowth from neurons. Spinal cord injury (SCI) is a devastating neurotrauma, affecting 250,000 to 500,000 people annually, and typically results in paralysis. Electrostimulation can promote neuronal growth, but the formation of a lesion cavity post-SCI inhibits regrowth, limiting its efficacy. Bridging the lesion with a structured, electroactive substrate to direct electrostimulation to growing neurites could support and drive neuronal regrowth through the lesion to enable functional recovery but to date, no such platform exists. This study describes the development of an electroconductive (15 ± 5 S/m), 3D-printed scaffold, comprising a polypyrrole/polycaprolactone framework filled with biomimetic & neurotrophic extracellular matrix. 3D printing allowed inclusion of channels in the scaffold designed to mimic the size of human corticospinal tracts to direct electrostimulation to growing neurons. Scaffolds exhibited excellent biocompatibility with both neurons and human primary astrocytes and maintained electrical and biofunctionality when scaled to match the size of human corticospinal tracts. When neurons were cultured for 7 days on the scaffolds under continuous electrostimulation (200 mV/mm, 12 Hz), significantly longer neurites were observed on electrically stimulated electroconductive scaffolds. These results demonstrate that electrostimulation applied via an anatomically-mimetic, 3D-printed electroconductive scaffold drives neurite outgrowth and represents a promising approach for treatment of spinal cord injury. [ABSTRACT FROM AUTHOR]

The value associated with reward is sensitive to external factors, such as the time between the choice and reward delivery as classically manipulated in temporal discounting tasks. Subjective preference for two reward options is dependent on objective variables of reward magnitude and reward delay. Single neuron correlates of reward value have been observed in regions, including ventral striatum, orbital, and medial prefrontal cortex. Brain imaging studies show cortico-striatal-limbic network activity related to subjective preferences. To explore how oscillatory dynamics represent reward processing across brain regions, we measured local field potentials of rats performing a temporal discounting task. Our goal was to use a data-driven approach to identify an electrophysiological marker that correlates with reward preference. We found that reward-locked oscillations at beta frequencies signaled the magnitude of reward and decayed with longer temporal delays. Electrodes in orbitofrontal/medial prefrontal cortex, anterior insula, ventral striatum, and amygdala individually increased power and were functionally connected at beta frequencies during reward outcome. Beta power during reward outcome correlated with subjective value as defined by a computational model fit to the discounting behavior. These data suggest that cortico-striatal beta oscillations are a reward signal correlated, which may represent subjective value and hold potential to serve as a biomarker and potential therapeutic target. [ABSTRACT FROM AUTHOR]

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Piezoelectric materials can actively provide a bioelectric microenvironment by converting mechanical stimulations into electrical signals. Combining the excellent flexibility of piezoelectric polymers and the outstanding piezoelectric properties of piezoelectric ceramics, piezoelectric composites are attractive in tissue repair due to their high response to micromechanical stimulations. However, issues such as agglomeration, dielectric differences, and poor interfacial contact with polymers have limited the role of ceramics in improving the overall properties of the composites. In this work, functionalized multiwalled carbon nanotubes (F-MWCNTs) are applied to disperse zinc oxide (ZnO) in the PVDF–TrFE matrix to prepare electrospun composite fiber films. Through the assistance of hydrogen bonding, F-MWCNTs act as bridges connecting ZnO nanoparticles with PVDF–TrFE, which improves the content and crystallinity of the β phase. Furthermore, this strategy enhances the local electric field and reduces dielectric differences, resulting in improved polarization and piezoelectric properties. Results show that the composite fiber film with 0.35 wt % F-MWCNTs could obtain an open-circuit voltage of up to 8.2 V, a β phase content of 83.36%, and a crystallinity of 57.63%. Meanwhile, due to the synergistic effect of F-MWCNTs and ZnO, the tensile strength and Young's modulus are increased from 3.5 and 11.0 to 6.6 and 19.49 MPa, respectively. Additionally, cellular experiments show that composite fiber films have good bioactivity and promote cell proliferation and adhesion, especially with 0.35 wt % F-MWCNTs. In conclusion, the composite fiber film possesses good piezoelectric and mechanical properties and enhances the cellular activity, making it a good tissue engineering scaffold. [ABSTRACT FROM AUTHOR]

In recent years, negative pressure wound dressings have garnered widespread attentions. However, it is challenging to drain the accumulated fluid under negative pressures for hydrogel dressings. To address this issue, this study prepared a chemical/physical duel‐network PEG‐CMCS/AG/MXene hydrogel composed by chemical disulfide crosslinked network of four‐arm polyethylene glycol/carboxymethyl chitosan (4‐Arm‐PEG‐SH/CMCS), and the physical network of hydrogen bond of agar (AG). Under near‐infrared light (NIR) irradiation, the PEG‐CMCS/AG/MXene hydrogel undergoes photothermal heating due to integrate of MXene, which destructs the hydrogen bond network and allows the removal of exudate through a mechanism mimicking the sweat gland‐like effect of skin pores. The photothermal heating effect also enables the antimicrobial activity to prevent wound infections. The excellent electrical conductivity of PEG‐CMCS/AG/MXene can promote cell proliferation under the external electrical stimulation (ES) in vitro. The animal experiments of full‐thickness skin defect model further demonstrate its ability to accelerate wound healing. The conversion between thioester and thiol achieved with L‐cysteine methyl ester hydrochloride (L‐CME) can provides the on‐demand dissolution of the dressing in situ. This study holds promises to provide a novel solution to the issue of fluid accumulations under hydrogel dressings and offers new approaches to alleviating or avoiding the significant secondary injuries caused by frequent dressing changes. [ABSTRACT FROM AUTHOR]

Electrical stimulation is an important adjuvant therapy for spinal surgery, but whether receiving electrical stimulation can improve the fusion rate after spinal surgery is still controversial. The purpose of this study was to analyse and evaluate the effect of electrical stimulation on the fusion rate after spinal surgery. We systematically searched for related articles published in the PubMed, Embase and Cochrane Library databases on or before September 30, 2023. The odds ratio (OR) with 95% confidence interval (CI) and the fusion rates of the experimental group and the control group were calculated by a random-effects meta-analysis model. The analysis showed that receiving electrical stimulation significantly increased the probability of successful spinal fusion (OR 2.66 [95% CI 1.79–3.97]), and the average fusion rate of the electrical stimulation group (86.8%) was significantly greater than that of the control group (73.7%). The fusion rate in the direct current (DC) stimulation group was 2.33 times greater than that in the control group (OR 2.33 [95% CI 1.37–3.96]), and that in the pulsed electromagnetic field (PEMF) group was 2.60 times greater than that in the control group (OR 2.60 [95% CI 1.29–5.27]). Similarly, the fusion rate in the capacitive coupling (CC) electrical stimulation group was 3.44 times greater than that in the control group (OR 3.44 [95% CI 1.75–6.75]), indicating that regardless of the type of electrical stimulation, the fusion rate after spinal surgery improved to a certain extent. Electrical stimulation as an adjuvant therapy seems to improve the fusion rate after spinal surgery to a certain extent, but the specific effectiveness of this therapy needs to be further studied. [ABSTRACT FROM AUTHOR]

Purpose: To estimate the effect of integrating custom-designed hand therapy video games (HTVG) with contralaterally controlled functional electrical stimulation (CCFES) therapy. Methods: Fifty-two stroke survivors with chronic (>6 months) upper limb hemiplegia were randomized to 12 weeks of CCFES or CCFES + HTVG. Treatment involved self-administration of technology-mediated therapy at home plus therapist-administered CCFES-assisted task practice in the lab. Pre- and post-treatment assessments were made of hand dexterity, upper limb impairment and activity limitation, and cognitive function. Results: No significant between-group differences were found on any outcome measure, and the average magnitudes of improvement within both groups were small. The incidence of technical problems with study devices at home was greater for the CCFES + HTVG group. This negatively affected adherence and may partially explain the absence of effect of HTVG. At end-of-treatment, large majorities of both treatment groups had positive perceptions of treatment efficacy and expressed enthusiasm for the treatments. Conclusion: This study makes an important contribution to the research literature on the importance of environmental factors, concomitant impairments, and technology simplification when designing technology-based therapies intended to be self-administered at home. This study failed to show any added benefit of HTVG to CCFES therapy. Clinicaltrials.gov (NCT03058796). IMPLICATIONS FOR REHABILITATION: Contralaterally controlled functional electrical stimulation (CCFES) is an emerging therapy for upper limb rehabilitation after stroke that is designed, in part, to be self-administered at home. While movement-soliciting video games have shown promise in rehabilitation, this study failed to show a significant added benefit of integrating CCFES with hand therapy video games. For technology-based therapies intended to be self-administered at home, this study brings to light the importance of making every component of rehabilitation technology as user friendly and trouble-free as possible. For technology-based therapies intended to be self-administered at home, this study brings to light the importance of assuring that the home environment is conducive to home-based therapy. [ABSTRACT FROM AUTHOR]

Recent interest in tissue engineering (TE) has focused on electrically conductive biomaterials. This has been inspired by the characteristics of the cells' microenvironment where signalling is supported by electrical stimulation. Numerous studies have demonstrated the positive influence of electrical stimulation on cell excitation to proliferate, differentiate, and deposit extracellular matrix. Even without external electrical stimulation, research shows that electrically active scaffolds can improve tissue regeneration capacity. Tissues like bone, muscle, and neural contain electrically excitable cells that respond to electrical cues provided by implanted biomaterials. To introduce an electrical pathway, TE scaffolds can incorporate conductive polymers, metallic nanoparticles, and ceramic nanostructures. However, these materials often do not meet implantation criteria, such as maintaining mechanical durability and degradation characteristics, making them unsuitable as scaffold matrices. Instead, depositing conductive layers on TE scaffolds has shown promise as an efficient alternative to creating electrically conductive structures. A stratified scaffold with an electroactive surface synergistically excites the cells through active top-pathway, with/without electrical stimulation, providing an ideal matrix for cell growth, proliferation, and tissue deposition. Additionally, these conductive coatings can be enriched with bioactive or pharmaceutical components to enhance the scaffold's biomedical performance. This review covers recent developments in electrically active biomedical coatings for TE. The physicochemical and biological properties of conductive coating materials, including polymers (polypyrrole, polyaniline and PEDOT:PSS), metallic nanoparticles (gold, silver) and inorganic (ceramic) particles (carbon nanotubes, graphene-based materials and Mxenes) are examined. Each section explores the conductive coatings' deposition techniques, deposition parameters, conductivity ranges, deposit morphology, cell responses, and toxicity levels in detail. Furthermore, the applications of these conductive layers, primarily in bone, muscle, and neural TE are considered, and findings from in vitro and in vivo investigations are presented. Tissue engineering (TE) scaffolds are crucial for human tissue replacement and acceleration of healing. Neural, muscle, bone, and skin tissues have electrically excitable cells, and their regeneration can be enhanced by electrically conductive scaffolds. However, standalone conductive materials often fall short for TE applications. An effective approach involves coating scaffolds with a conductive layer, finely tuning surface properties while leveraging the scaffold's innate biological and physical support. Further enhancement is achieved by modifying the conductive layer with pharmaceutical components. This review explores the under-reviewed topic of conductive coatings in tissue engineering, introducing conductive biomaterial coatings and analyzing their biological interactions. It provides insights into enhancing scaffold functionality for tissue regeneration, bridging a critical gap in current literature. [Display omitted] [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) have become reliable green energy harvesters by converting biomechanical motions into electricity. However, the inevitable charge leakage and poor electric field (EF) of conventional TENG result in inferior tribo‐charge density on the active layer. In this paper, TiO2‐MXene incorporated polystyrene (PS) nanofiber membrane (PTMx NFM) charge trapping interlayer is introduced into single electrode mode TENG (S‐TENG) to prevent electron loss at the electrode interface. Surprisingly, this charge‐trapping mechanism augments the surface charge density and electric output performance of TENGs. Polyvinylidene difluoride (PVDF) mixed polyurethane (PU) NFM is used as tribo‐active layer, which improves the crystallinity and mechanical property of PVDF to prevent delamination during long cycle tests. Herein, the effect of this double‐layer capacitive model is explained experimentally and theoretically. With optimization of the PTMx interlayer thickness, S‐TENG exhibits a maximum open‐circuit voltage of (280 V), short‐circuit current of (20 µA) transfer charge of (120 nC), and power density of (25.2 µW cm−2). Then, this energy is utilized to charge electrical appliances. In addition, the influence of AC/DC EF simulation in wound healing management (vitro L929 cell migration, vivo tissue regeneration) is also investigated by changing the polarity of trans‐epithelial potential (TEP) distribution in the wounded area. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusions Dystonia presents a growing concern based on evolving prevalence insights. Previous research found that, in cervical dystonia, high‐frequency repetitive somatosensory stimulation (RSS; HF‐RSS) applied on digital nerves paradoxically diminishes sensorimotor inhibitory mechanisms, whereas low‐frequency RSS (LF‐RSS) increases them. However, direct testing on affected body parts was not conducted.This study aims to investigate whether RSS applied directly to forearm muscles involved in focal hand dystonia can modulate cortical inhibitory mechanisms and clinical symptoms.We applied HF‐RSS and LF‐RSS, the latter either synchronously or asynchronously, on forearm muscles involved in dystonia. Outcome measures included paired‐pulse somatosensory evoked potentials, spatial lateral inhibition measured by double‐pulse somatosensory evoked potentials, short intracortical inhibition tested with transcranial magnetic stimulation, electromyographic activity from dystonic muscles, and behavioral measures of hand function.Both synchronous and asynchronous low‐frequency somatosensory stimulation improved cortical inhibitory interactions, indicated by increased short intracortical inhibition and lateral spatial inhibition, as well as decreased amplitude of paired‐pulse somatosensory evoked potentials. Opposite effects were observed with high‐frequency stimulation. Changes in electrophysiological markers were paralleled by behavioral outcomes: although low‐frequency stimulations improved hand function tests and reduced activation of dystonic muscles, high‐frequency stimulation operated in an opposite direction.Our findings confirm the presence of abnormal homeostatic plasticity in response to RSS in the sensorimotor system of patients with dystonia, specifically in inhibitory circuits. Importantly, this aberrant response can be harnessed for therapeutic purposes through the application of low‐frequency electrical stimulation directly over dystonic muscles. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Long‐range thalamocortical communication is central to anesthesia‐induced loss of consciousness and its reversal. However, isolating the specific neural networks connecting thalamic nuclei with various cortical regions for state‐specific anesthesia regulation is challenging, with the biological underpinnings still largely unknown. Here, simultaneous electroencephalogram‐fuctional magnetic resonance imaging (EEG‐fMRI) and deep brain stimulation are applied to the intralaminar thalamus in macaques under finely‐tuned propofol anesthesia. This approach led to the identification of an intralaminar‐driven network responsible for rapid arousal during slow‐wave oscillations. A network‐based RNA‐sequencing analysis is conducted of region‐, layer‐, and cell‐specific gene expression data from independent transcriptomic atlases and identifies 2489 genes preferentially expressed within this arousal network, notably enriched in potassium channels and excitatory, parvalbumin‐expressing neurons, and oligodendrocytes. Comparison with human RNA‐sequencing data highlights conserved molecular and cellular architectures that enable the matching of homologous genes, protein interactions, and cell types across primates, providing novel insight into network‐focused transcriptional signatures of arousal. [ABSTRACT FROM AUTHOR]

BACKGROUND: The objective of this research was to test whether efficient tinnitus suppression could be achieved by electrical stimulation of the single most basal electrode contact of a cochlear implant. This approach simulates the effects of electrical stimulation using a round-window electrode. METHODS: The study was performed in 10 adult cochlear implant patients showing complete or almost complete tinnitus suppression during electrical stimulation with their standard fitting-MAP. In all patients, tinnitus appeared again when the implant was switched off. Five Nucleus implant (1 CI532, 4 CI24RE CA) users and 5 Mi12xx series with FLEX28 electrodes with at least 6 months of CI experience were included. Two types of stimulation were presented at the most basal CI contact: a constant pulse train and a modulated pulse train. The variation in pulse rates was low rate (100-300 pps) and high (≥900 pps), and the current level ranged from the C-level to less than the T-level for both stimulation types. The effect of acute electrical stimulation at the most basal electrode contact was compared to the effect obtained with multichannel stimulation with the patient's current fitting MAP. Electrical stimulation was paused between tests with different stimulation types until tinnitus returned to baseline intensity. Patients reported Visual Analog Scale (VAS) scores for tinnitus loudness and intrusiveness during normal CI use and for each single contact stimulation type. RESULTS: Eight participants perceived complete suppression with one or more stimulation patterns. In 2 patients, suppression was less efficient than full-band CI stimulation. Louder stimuli are generally perceived as annoying and less effective in reducing tinnitus. In FLEX28 patients, it was also possible to obtain full tinnitus suppression with current amplitudes under the thresholds for auditory perception (this was not tested in patients with the Nucleus device). CONCLUSION: In 8 of the 10 included patients, we were able to obtain complete or almost complete tinnitus suppression with electrical stimulation at only 1 most basal electrode contact. Therefore, round-window stimulation with a single electrode may be a potential treatment for tinnitus in patients with significant residual hearing. The long-term effects of this therapy should be confirmed in future studies. [ABSTRACT FROM AUTHOR]

The prevalence of skeletal muscle atrophy, caused by disease and aging, is rising as life expectancy increases. Exercise is the most effective treatment option; however, it is often impractical for individuals suffering from disease or bedridden. The formulation of non-exercise-based interventions is necessary. This study assessed the impact of acupuncture (AC), electro-acupuncture (EA), and electrical stimulation (ES) on muscle mass and contractile properties in a model of casting-induced muscle atrophy. Sprague-Dawley rats (n = 40) were assigned to five groups: control (CON), cast (CT), cast receiving AC (CT-AC), cast receiving EA (CT-EA), and cast receiving ES (CT-ES) (n = 8 each). Treatments were 15 min and three times/week for 14 days. Contractile properties and protein markers of atrophy and inflammation were measured. Casting decreased muscle mass and fiber cross-sectional area, but AC, EA, and ES attenuated cast-induced muscle atrophy. All treatments increased peak twitch tension compared to CT. CT increased the protein levels of MAFbx and MuRF1, while AC, EA, and ES mitigated the elevation of these proteins. Our results indicate that acupuncture, electro-acupuncture, and electrical stimulation show promise as therapeutic strategies to counteract skeletal muscle loss and dysfunction resulting from disuse atrophy caused by injury, disease, and aging. [ABSTRACT FROM AUTHOR]

(1) Background: Female sexual dysfunction (FSD) and overactive bladder (OAB) are prevalent disorders that significantly impair women's quality of life. While pelvic floor muscle training (PFMT) is a well-established treatment for OAB, its effectiveness for FSD remains uncertain. Recent studies suggest that intravaginal electrical stimulation (IVES) may enhance the effects of PFMT. Therefore, this study aimed to evaluate the efficacy of combining IVES with PFMT to improve sexual function and bladder control in women with OAB and FSD. (2) Methods: A total of 40 women with FSD and OAB as determined by the Female Sexual Function Index (FSFI) and Overactive Bladder Symptom Score (OABSS) were randomized into two groups: group 1, the intravaginal electrical stimulation group (IVESG) (n = 20), and group 2, the placebo control group (CG) (n = 20). Patients in both groups received PFMT during the trial, and the IVESG underwent 10 weeks of electrical stimulation. The primary outcome was the change in the FSFI score from baseline to week 4 and week 10. The secondary outcome was a comparison of the OABSS values at week 4 and week 10 of the trial. (3) Results: After treatment, the IVESG scores for the total FSFI, sexual arousal and orgasm, increased significantly (p < 0.05). After 10 weeks of treatment, the OABSS values for IVESG were significantly lower (p < 0.01). After 10 weeks of treatment, the percentage of patients with mild OAB in the IVESG and CG increased by 53.33% and 60%, respectively, while the percentage of patients with both moderate and severe OAB decreased, especially in the IVESG, where patients with severe OAB were non-existent after 10 weeks of treatment. (4) Conclusions: IVES combined with PFMT improved objective and subjective measures of FSD and OAB. There was a significant improvement in FSD (including arousal and orgasmic domain scores). This study concludes that IVES is an effective conservative treatment. [ABSTRACT FROM AUTHOR]

Post-stroke depression (PSD) is a common neurological and psychiatric sequelae following a stroke, often surpassing the primary effects of the stroke due to its strong correlation with high mortality rates. In recent years, non-pharmacological therapy has garnered significant attention as a supplementary treatment for PSD, becoming widely adopted in clinical practice. However, the efficacy of specific intervention strategies remains unclear. This study aimed to conduct a network meta-analysis (NMA) of published studies to compare the efficacy of different non-pharmacological therapies for treating PSD. We systematically searched five databases from inception through March 2024 to identify randomized controlled trials (RCTs) evaluating non-pharmacological therapies for the treatment of PSD. We considered individual intervention and intervention class. Intervention classes included traditional Chinese medicine (TCM), non-invasive electrotherapy stimulation (NIES), psychotherapy (PT), exercise therapy, hyperbaric oxygen, and combined interventions. The NMA was conducted using R and Stata software, following a frequency-based methodology. Assessment of methodological quality and risk of bias was conducted using the Risk of Bias assessment tool 2.0. Therapies were ranked using the P-score, and box-plots visualization, meta-regression, and sensitivity analysis, were performed to assess transitivity, heterogeneity, and consistency, respectively. The NMA included 43 studies with a total of 3138 participants. Random-effects models revealed significant efficacy for acupuncture (ACUP) (P-score = 0.92; pooled standardized mean difference (95% CI): −3.12 (−4.63 to −1.60)) and transcranial direct current stimulation (P-score = 0.85; −2.78 (−5.06 to −0.49)) compared to the treatment as usual (TAU) group. In categorical comparisons, TCM_PT (P-score = 0.82; −1.91 (−3.54 to −0.28)), TCM (P-score = 0.79; −1.65 (−2.33 to −0.97)), and NIES (P-score = 0.74; −1.54 (−2.62 to −0.46)) showed significant differences compared to TAU group. Furthermore, our results indicated no significant difference between PT and the control groups. However, Confidence in Network Meta-Analysis results indicated very low overall evidence grade. Limited evidence suggests that ACUP may be the most effective non-pharmacological therapy for improving PSD, and TCM_PT is the best intervention class. However, the evidence quality is very low, underscoring the need for additional high-quality RCTs to validate these findings, particularly given the limited number of RCTs available for each therapy. • Acupuncture showed the greatest improvement in depression symptoms in patients with post-stroke depression. • Given the overlap between stroke and depression symptoms, passive therapiesmay be more appropriate and efficacious for patients. • Categorical comparisons suggest that traditional Chinese medicine combined with psychotherapy may have the best efficacy in treating post-stroke depression. [ABSTRACT FROM AUTHOR]

The restoration of adequate function and sensation in nerves following an injury is often insufficient. Electrical stimulation (ES) applied during nerve repair can promote axon regeneration, which may enhance the likelihood of successful functional recovery. However, increasing operation time and complexity are associated with limited clinical use of ES. This study aims to better assess whether short-duration ES types (voltage mode vs. current mode) are able to produce enhanced regenerative activity following peripheral nerve repair in rat models. Wistar rats were randomly divided into 3 groups: no ES (control), 30-minute ES with a current pulse, and 30-minute ES with a voltage pulse. All groups underwent sciatic nerve transection and repair using a silicone tube to bridge the 6-mm gap between the stumps. In the 2 groups other than the control, ES was applied after the surgical repair. Outcomes were evaluated using electrophysiology, histology, and serial walking track analysis. Biweekly walking tracks test over 12 weeks revealed that subjects that underwent ES experienced more rapid functional improvement than subjects that underwent repair alone. Electrophysiological analysis of the newly intratubular sciatic nerve at week 12 revealed strong motor function recovery in rats that underwent 30-minute ES. Histologic analysis of the sciatic nerve and its tibial branch at 12 weeks demonstrated robust axon regrowth in all groups. Both types of short-duration ES applied during nerve repair can promote axon regrowth and enhance the chances of successful functional recovery. [ABSTRACT FROM AUTHOR]

Here, a novel kind of composite scaffold was fabricated by loading vascular endothelial growth factor (VEGF) and gastrodin liposome (GAS-LP) into electrospun silk fibroin/graphene oxide(SF/GO)nanofibrous and silk fibroin sponge-filled, respectively. Our results demonstrated that VEGF and GAS exhibited different release patterns in vitro which VEGF showed rapid release rate in the first few days while GAS was released slowly and continuously as encapsulated in liposomes. The scaffolds realized the combination of intraneural vascularization drugs and electrical stimulation effectively, leading to enhanced growth of RSC96 cells. Furthermore, the scaffolds could protect RSC96 cells in an inflammatory environment. [ABSTRACT FROM AUTHOR]

Background: Tissue stimulations greatly affect cell growth, phenotype, and function, and they play an important role in modeling tissue physiology. With the goal of understanding the cellular mechanisms underlying the response of tissues to external stimulations, in vitro models of tissue stimulation have been developed in hopes of recapitulating in vivo tissue function. Methods: Herein we review the efforts to create and validate tissue stimulators responsive to electrical or mechanical stimulation including tensile, compression, torsion, and shear. Results: Engineered tissue platforms have been designed to allow tissues to be subjected to selected types of mechanical stimulation from simple uniaxial to humanoid robotic stain through equal‐biaxial strain. Similarly, electrical stimulators have been developed to apply selected electrical signal shapes, amplitudes, and load cycles to tissues, lending to usage in stem cell‐derived tissue development, tissue maturation, and tissue functional regeneration. Some stimulators also allow for the observation of tissue morphology in real‐time while cells undergo stimulation. Discussion on the challenges and limitations of tissue simulator development is provided. Conclusions: Despite advances in the development of useful tissue stimulators, opportunities for improvement remain to better reproduce physiological functions by accounting for complex loading cycles, electrical and mechanical induction coupled with biological stimuli, and changes in strain affected by applied inputs. [ABSTRACT FROM AUTHOR]

Background: Although biofeedback with contingent electrical stimulation (CES) has demonstrated the reduction effect on sleep bruxism (SB), the relationship between the actual applied CES intensity and efficacy remains uncertain. Objective: This study aimed to investigate whether the reduction of bruxism events and jaw muscle symptoms could vary according to the intensity of CES and in probable sleep bruxers. Methods: Twenty probable sleep bruxers were initially screened for bruxer confirmation based on a 2‐week recording of SB events with a portable electromyography recorder (BUTLER®GrindCare®, GC4). A 3‐week recording was conducted without CES using a GC4, followed by another 3‐week recording with CES. At baseline and before and after the CES (+) session, clinical muscle symptoms were assessed using a 0–10 numerical rating scale (NRS). The relationships between the actual applied CES intensity and the number of SB events/hour, as well as the NRS of clinical muscle symptoms, were analysed. Results: The actual applied CES intensity was positively correlated with the reduction rate of the number of SB events/hour (R =.643, p =.002), as well as with the reduction rate of NRS for pain, unpleasantness, fatigue, tension and stiffness (R >.500, p <.011). Conclusion: Higher CES elicited a more robust reduction in SB events and clinical muscle symptoms, in probable bruxers. Prior to selecting CES biofeedback as a management option for SB, it would be beneficial to assess the tolerance threshold of CES in each bruxer in order to predict the effectiveness of CES in probable sleep bruxers. [ABSTRACT FROM AUTHOR]

Background and Aim: Research has shown that inflammation is an important factor in atherosclerosis. New markers of heart diseases such as natriuretic peptide-B (BNP) and osteoprotegerin (OPG) during inflammation from atherosclerotic lesions, monocytes, macrophages and endothelium of heart patients; it is secreted and plays an essential role in heart attack patients. The present research has investigated the effect of a session of physical activity and early electrical stimulation on some inflammatory markers of infarcted rats. Materials and Methods: In this controlled experimental study with a control group, 50 rats with an average weight of 210±20 g were randomly divided into five groups including healthy, infarcted, physical activity, electrical stimulation, and physical activity + electrical stimulation. The intervention groups underwent physical activity on a treadmill (with a speed of 10 to 18 m/min for one hour) and electrical stimulation (with a foot shock device for 0.5 mA and 20 minutes) for one session. Then, immediately after the intervention, the serum levels of the variables were checked by ELISA method. Data analysis was done with one-way ANOVA test at p < 0.05 significance. Results: Induction of infarction indicated a significant increase in the serum levels of BNP and OPG ( p = 0.0001 and p = 0.001 respectively). Moreover, acute physical activity and its combination with electrical stimulation had no significant effect on BNP values (p = 0.39) and OPG serum concentration was not affected by acute physical activity (p = 0.42) but OPG levels in electrical stimulation groups showed a significant decrease as compared to acute physical activity (p = 0.02) Conclusion: It seems that early electrical stimulation alone and along with acute physical activity, by reducing the concentration of BNP and OPG, has no effect on the recovery process of heart markers and needs more study. [ABSTRACT FROM AUTHOR]

Recovery after visual loss is a key goal of neuroscience and treatments able to improve visual function are still largely lacking. Glaucoma, one of the leading causes of visual disability in the world, is usually associated with elevated intraocular pressure (IOP), but a subset of "normal tension glaucoma" patients develop damage without ever manifesting high IOP. Sometimes, even in patients with good control of IOP, retinal ganglion cell degeneration can progress to forward blindness. Moreover, usually the damage already caused by the disease remains. These considerations underline the need to find new, effective treatments and solutions to add to the standard ones. In this paper, we expose the most important data supporting the use of alternating current stimulation, including the theoretical bases of this approach, in glaucoma. [ABSTRACT FROM AUTHOR]

Background and aims: Electrical stimulation (ES) has been shown to substantially enhance the quality of life by alleviating pain in patients with chronic wounds. This study aimed to observe the effects of low‐frequency pulsed wearable ES at the common peroneal nerve on chronic refractory wounds of the lower limb. Methods: Forty‐eight participants were randomly divided into control group (n = 24) and treatment group (n = 24) in this study. The control group received standard wound care (SWC) exclusively, whereas the treatment group was administered both SWC and the wearable low‐frequency ES targeting the common peroneal nerve. Measurements of wound area, pain intensity, wound status, and quality of life scores were systematically recorded both before and after 4 weeks treatment. Results: After 4 weeks of intervention, the percentage area reduction was significantly higher in the treatment group compared to the control group (Z = −3.9, p < 0.001), and the healing rate of the treatment group was significantly higher than that of the control group (33% vs. 4%). Moreover, the Visual Analog Scale for Pain score (β = −0.65, p = 0.019), the Bates‐Jensen Wound Assessment Tool score (p < 0.05), and the questionnaire on quality of life with chronic wounds (Wound‐Qol) score (β = −4.23, p = 0.003) were significantly decreased in the patients in the treatment group compared to the control group. Conclusion: The wearable low‐frequency pulsed ES at the common peroneal nerve for the treatment of chronic refractory wounds showed significant improvement and were far superior compared to SWC. Future research should broaden its scope to include a diverse range of wound types and benefit from collaboration across multiple research centers. Key messages: Traditional wound dressings are currently inadequate for addressing chronic wound closure.The wearable electrical stimulation (ES), an economical and noninvasive form of physical therapy, can be beneficial in facilitating the healing process of chronic wounds.The purpose of this study was to observe the effects of wearable low‐frequency pulsed ES at the common peroneal nerve on chronic refractory wounds of the lower limb.The wearable low‐frequency pulsed ES at the common peroneal nerve for the treatment of chronic refractory wounds showed significant improvement and were far superior compared to standard wound care. [ABSTRACT FROM AUTHOR]

Repetitive passive movement (RPM) enhances reciprocal inhibition. RPM is more effective when performed rapidly and at wide joint angles. However, patients with limited joint range of motion may not receive the most effective RPM. Therefore, having an alternative method for performing RPM in patients who cannot perform actual exercise due to limited joint motion is necessary. This study investigated the effects of RPM on spinal excitability using a visual kinesthetic illusion. Participants included 17 healthy adults (7 women). Measurements were taken before, during, and immediately after the intervention. We established two intervention conditions: the control condition, in which participants focused their attention forward, and the illusion condition, in which participants watched a video about RPM. F-waves from the tibialis anterior and soleus muscles were measured, and F-wave persistence and F/M amplitude ratios were analyzed. Under the illusion condition, compared with the preintervention condition, the F/M amplitude ratio of the tibialis anterior increased by approximately 44% during the intervention (p < 0.05), whereas the F-wave persistence of the soleus decreased by approximately 23% from the immediate start of the intervention (p < 0.05). This study suggests that a visual kinesthetic illusion can increase the spinal excitability of the tibialis anterior, whereas reciprocal inhibition can decrease the spinal excitability of the soleus. [ABSTRACT FROM AUTHOR]

The goal of this study was to examine the characteristics of electrically induced retinal damage. A retinal prosthesis must be both effective and safe, but most research related to electrical stimulation of the retina has involved measures of efficacy (for example, stimulus threshold), while relatively little research has investigated the safety of electrical stimulation. In this study, a single platinum microelectrode was inserted into the vitreous cavity of normally-sighted adult Long Evans pigmented rats. In one group of animals, no contact was made between the electrode and the retina and current pulses of 0.05 (n = 3) and 0.2 (n = 6) μC/phase were applied. In a second group, visible contact (slight dimpling of the retina) was made between the electrode and the retina and current pulses of 0.09 (n = 4) μC/phase were applied. In both cases, stimulus pulses (biphasic, cathodic first, 1 ms/phase) were applied for 1 h at 100 Hz. Also, control experiments were run with no electrical stimulation with retina contact (n = 4) and with no retinal contact (n = 3). After stimulation, the animal was survived for 2 weeks with ocular photography and electroretinography (ERG) to document changes. During the follow-up period, retinal changes were observed only when the electrode contacted the retina, with or without electrical stimulation. No difference was noted in ERG amplitude or latency comparing the test eye to the stimulated eye. Histological analysis was performed after sacrifice at 2 weeks. A semi-quantitative method for grading 18 features of retina/RPE/choroidal appearance was established and integer grades applied to both test and control eyes. Using this method and comparing the most severely affected area (highest grade), significant differences ( p < 0.05) were noted between experiments with retinal contact and without retinal contact in all features except inner nuclear layer thickness. No difference was noted within a group based on the intensity of electrical stimulus applied. The size of the affected area was significantly larger with both retinal contact and electrical stimulation compared to withretinal contact alone. We conclude that mechanical pressure alone and mechanical pressure with excessive electrical stimulation causes damageto the retina but that electrical stimulation coupled with mechanical pressure increases the area of the damage.

Abstract Background Atrial fibrillation (AF) stands as a prevalent and detrimental arrhythmic disorder, characterized by intricate pathophysiological mechanisms. The availability of reliable and reproducible AF models is pivotal in unraveling the underlying mechanisms of this complex condition. Unfortunately, the researchers are still confronted with the absence of consistent in vitro AF models, hindering progress in this crucial area of research. Methods Human induced pluripotent stem cells derived atrial myocytes (hiPSC-AMs) were generated based on the GiWi methods and were verified by whole-cell patch clamp, immunofluorescent staining, and flow cytometry. Then hiPSC-AMs were employed to establish the AF model by HS. Whole-cell patch clamp technique and calcium imaging were used to identify the AF model. The stability of 29 reference genes was evaluated using delta-Ct, GeNorm, NormFinder, and BestKeeper algorithms; Results HiPSC-AMs displayed atrial myocyte action potentials and expressed the atrial-specific protein MLC-2 A and NR2F2, about 70% of the cardiomyocytes were MLC-2 A positive. After HS, hiPSC-AMs showed a significant increase in beating frequency, a shortened action potential duration, and increased calcium transient frequency. Of the 29 candidate genes, the top five most stably ranked genes were ABL1, RPL37A, POP4, RPL30, and EIF2B1. After normalization using ABL1, KCNJ2 was significantly upregulated in the AF model; Conclusions: In the hiPSC-AMs AF model established by HS, ABL1 provides greater normalization efficiency than commonly used GAPDH.

The purpose of this systematic review was to assess the currently available evidence for the use of external stimulation to modulate neural activity and promote peripheral nerve regeneration. The most common external stimulations are electrical stimulation (ES), optogenetic stimulation (OS), and magnetic stimulation (MS). Understanding the comparative effectiveness of these stimulation methods is pivotal in advancing therapeutic interventions for peripheral nerve injuries. This systematic review focused on these three external stimulation modalities as potential strategies to enhance peripheral nerve repair (PNR). We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework to systematically evaluate and compare the efficiency of ES, OS, and MS in PNR. The review included studies published between 2018 and 2023 using ES, OS, or MS for PNR focused on enhancing recovery of peripheral nerve injuries in rodent models identified through PubMed and Google Scholar. The search strategies and inclusion criteria identified 19 studies (13 ES, 4 OS, and 2 MS) for detailed analysis, focusing on critical parameters such as functional recovery, histological outcomes, and electrophysiological data. Although ES demonstrated a consistent improvement in all the analyses, high-frequency repetitive MS (HFr-MS) emerged as a promising modality. HFr-MS demonstrated accelerated PNR, as histological and electrophysiological evidence indicated. In contrast, OS exhibited superior functional recovery outcomes. Notable limitations include constrained MS and OS data sets and the challenge of comparing relative improvements because of methodological diversity in evaluation techniques. Our findings underscore the potential of HFr-MS and OS in PNR while emphasizing the critical need for standardized testing protocols to facilitate meaningful cross-study comparisons. External stimulations have the potential to improve functional recovery in patients with nerve injury.

The role of electrical stimulation in peripheral nerve regeneration is reviewed, including a brief background and proposed mechanism of action. Studies in animal as well as human models are reviewed. Current recommendations and future directions are addressed.

Abstract 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.

BackgroundAnkle instability results in sensory and motor impairments. Typically, health professionals recommend conservative treatment as the initial approach for individuals with this condition. One such treatment option is Electrical Stimulation (ES). This systematic review assesses the effects of ES techniques on postural control measures in cases of ankle instability.MethodWe systematically searched five electronic databases: ClinicalTrials.gov, PubMed, Scopus, SPORTDiscus, and Web of Science. To evaluate the quality of the included articles, we utilized the PEDro checklist. We extracted data on population, intervention, and outcomes and synthesized them narratively.ResultES decreased the time needed to stabilize the center of pressure, velocity, displacement, and area, thereby enhancing the performance of clinical tests. While postural stability indexes remained unaffected, the gait inversion angle increased with electrical stimulation.ConclusionThese results suggest that ES interventions are crucial in enhancing postural control in subjects with ankle instability compared to coordination exercises therapy alone. Stochastic resonance reduced A/P and M/L TTS, COP velocity, COP displacement, and COP area, resulting in enhanced postural control.

Recovery after visual loss is a key goal of neuroscience and treatments able to improve visual function are still largely lacking. Glaucoma, one of the leading causes of visual disability in the world, is usually associated with elevated intraocular pressure (IOP), but a subset of “normal tension glaucoma” patients develop damage without ever manifesting high IOP. Sometimes, even in patients with good control of IOP, retinal ganglion cell degeneration can progress to forward blindness. Moreover, usually the damage already caused by the disease remains. These considerations underline the need to find new, effective treatments and solutions to add to the standard ones. In this paper, we expose the most important data supporting the use of alternating current stimulation, including the theoretical bases of this approach, in glaucoma.

Abstract Background The previous effects of acupuncture-related interventions in improving chemotherapy-induced peripheral neuropathy (CIPN) symptoms and quality of life (QoL) remain unclear in terms of pairwise comparisons. Aims This systematic review and network meta-analysis aimed to determine the hierarchical effects of acupuncture-related interventions on symptoms, pain, and QoL associated with CIPN in cancer patients undergoing chemotherapy. Methods Nine electronic databases were searched, including PubMed, Embase, Cochrane Library, EBSCO, Medline Ovid, Airiti Library, China National Knowledge Infrastructure (CNKI), China Journal full-text database (CJFD), and Wanfang. Medical subject heading terms and text words were used to search for eligible randomized controlled trials published from database inception to May 2023. Results A total of 33 studies involving 2,027 participants were included. Pairwise meta-analysis revealed that acupuncture-related interventions were superior to usual care, medication, or dietary supplements in improving CIPN symptoms, CIPN pain, and QoL. Furthermore, network meta-analysis indicated that acupuncture plus electrical stimulation (acupuncture-E) had the greatest overall effect among the various interventions. The surface under the cumulative ranking curve (SUCRA) revealed that acupuncture-E ranked the highest in improving CINP symptoms. Acupuncture alone was most effective in reducing CIPN pain, and acupuncture plus moxibustion (acupuncture-M) ranked highest in enhancing QoL. Conclusion This finding suggests that acupuncture-related interventions can provide patients with benefits in improving CIPN symptoms, pain, and QoL. In particular, acupuncture-E could be the most effective approach in which the provided evidence offers diverse options for cancer patients and healthcare professionals. Implication for the profession and/or patient care These findings provide valuable insights into the potential benefits of acupuncture-related interventions for managing symptoms, pain, and QoL associated with CIPN in patients undergoing chemotherapy. Among the various interventions studied, overall, acupuncture-E had the most significant impact and was effective for a minimum duration of 3 weeks. On the other hand, transcutaneous electrical acupoint/nerve stimulation (TEAS) was identified as a noninvasive and feasible alternative for patients who had concerns about needles or the risk of bleeding. It is recommended that TEAS interventions should be carried out for a longer period, preferably lasting 4 weeks, to achieve optimal outcomes. Trial registration The study protocol was registered in the International Prospective Register of Systematic Reviews. Registration Number: CRD42022319871.

The prevalence of skeletal muscle atrophy, caused by disease and aging, is rising as life expectancy increases. Exercise is the most effective treatment option; however, it is often impractical for individuals suffering from disease or bedridden. The formulation of non-exercise-based interventions is necessary. This study assessed the impact of acupuncture (AC), electro-acupuncture (EA), and electrical stimulation (ES) on muscle mass and contractile properties in a model of casting-induced muscle atrophy. Sprague-Dawley rats (n = 40) were assigned to five groups: control (CON), cast (CT), cast receiving AC (CT-AC), cast receiving EA (CT-EA), and cast receiving ES (CT-ES) (n = 8 each). Treatments were 15 min and three times/week for 14 days. Contractile properties and protein markers of atrophy and inflammation were measured. Casting decreased muscle mass and fiber cross-sectional area, but AC, EA, and ES attenuated cast-induced muscle atrophy. All treatments increased peak twitch tension compared to CT. CT increased the protein levels of MAFbx and MuRF1, while AC, EA, and ES mitigated the elevation of these proteins. Our results indicate that acupuncture, electro-acupuncture, and electrical stimulation show promise as therapeutic strategies to counteract skeletal muscle loss and dysfunction resulting from disuse atrophy caused by injury, disease, and aging.