Search Results (2,060)

A versatile and modular microfluidic system for cell co-culture has been developed. Microfluidic chips, each featuring dual compartments separated by a porous membrane, have been fabricated and assembled within the system to facilitate fluidic interconnection and cell–cell communication through the chip assembly. A set of fluidic valves has been successfully integrated to regulate the flow through the chip assembly. The system allows for chip assembly in various arrangements, including in parallel, in series, and complex connections. Individual chips can be interconnected or disconnected within the system at any time. Moreover, the spatial order and orientation of the chips can be adjusted as needed, enabling the study of different cell–cell arrangements and the impact of the presence or absence of specific cell types. The utility of the system has been evaluated by culturing and interconnecting multi-monolayers of intestinal epithelial cells as a model of the complex cellular system. Epithelial monolayers were grown in multiple chips and interconnected in various configurations. The transepithelial electrical resistance and permeability profiles were investigated in detail for these configurations upon treatment of the cells with dextran sulfate sodium. Immune cells were stimulated through the epithelial layers and the expression of inflammatory cytokines was detected. This miniaturized platform offers controlled conditions for co-culturing key cellular components and assessing potential therapeutic agents in a physiologically relevant setting. Full article

One emerging method in home stroke rehabilitation is digital technology. However, existing approaches typically target one domain (e.g., upper limb). Moreover, existing interventions do not cater to older adults with stroke (OAwS), especially those with high motor impairment, who require adjunct therapeutic agents to independently perform challenging exercises. We examined the feasibility of Smartphone-based Exercise Training after Stroke (SETS) with Functional Electrical Stimulation (FES). A total of 12 participants (67 ± 5 years) with stroke (onset > 6 months) exhibiting moderate-to-high motor impairment (Chedoke McMaster Leg ≤ 4/7) underwent 6 weeks of multicomponent (gait, functional strength, dynamic balance) training integrated with FES to paretic lower limb muscles. Primary measures included safety and adherence. Secondary measures included motivation, acceptability and attitude, usability, and clinical measures of gait and balance function like the 10-Meter Walk Test and Mini-BESTest. Participants reported no adverse events and moderate-to-high adherence (84.17 ± 11.24%) and improvement (up to 40%) in motivation, acceptability, and attitude and system usability. Participants also showed pre-post improvements in all measures of gait and balance function (p < 0.05). Integrating SETS and FES is feasible and yields short-term gains in gait and balance function among OAwS. Future studies could validate our findings by examining its efficacy with control groups to identify the differential effects of SETS and FES. Full article

Advances in non-invasive neuromodulation (NM) have enabled practitioners to modulate neural activity safely, offering a promising approach to treating neuropsychiatric and neurological conditions. This study aimed to analyze the training profiles of NM practitioners and assess their perceptions of NM’s clinical efficacy, safety, and patient satisfaction. An online survey was conducted among 117 practitioners in various healthcare fields, using the Clinical Global Impression (CGI) scale to gauge outcomes. The findings indicate that 99.13% of practitioners perceive NM as effective, with high rates of patient improvement in quality of life and symptom management. The study underscores the importance of standardized NM training protocols to enhance therapeutic outcomes. Full article

Atrial fibrillation (AF) is associated with energetic deficiency and oxidative stress due to mitochondrial dysfunction, resulting in electric remodeling. Long-term treatment was found to ameliorate mitochondrial function and decrease inducibility in animal models. No studies examine the short-term effect of SGLT-2 inhibitors administration in AF. In the present study, the samples of the right atrial appendage collected from 10 patients subjected to elective cardiac surgery were sliced and incubated in a control buffer (EMPA 0), 0.2 µmol/L empagliflozin (EMPA 0.2), or 1.0 µmol/L (EMPA 1). The expression of mitochondrial biogenesis, fission, and fusion proteins was measured by Western blot after 30 min of electrical stimulation (control—1 Hz or tachypacing—5 Hz). The PGC-1α protein expression was increased after 30 min of stimulation with 1 Hz when incubated under a higher concentration of empagliflozin. After tachypacing, EMPA 0.2 increased PGC-1α, while EMPA 1.0 upregulated NRF-1. Both concentrations increased NRF-2 during control stimulation. The oxygen consumption was higher in AF, and was decreased by SGLT-2i. Empagliflozin exerts dynamic effects on the expression of PGC-1α and other proteins involved in mitochondrial function and oxidative stress in cardiomyocytes and may modulate cellular response to tachycardia. Full article

Background: Total hip replacement replaces the femoral head, which cannot heal, with an artificial femoral shaft to ensure the patient’s normal life. However, due to the stress-masking effect of the proximal femur loaded with the artificial femur stem, the implant bears a large part of the load, resulting in insufficient stress stimulation of the proximal femur and bone waste remodeling. In turn, it is easy to lose bone, resulting in loosening. As a new treatment method, electrical stimulation has been widely used for bone loss, nonunion, and other diseases, and it has achieved good therapeutic effects. Methods: Therefore, in this work, electrical stimulation was introduced for postoperative density assessment, and a new disuse remodeling model was established to simulate density loss after remodeling and the resistance effect of electrical stimulation. The effects of various parameters on density loss in the model are discussed. Results: The simulation results revealed significant stress masking and density loss in the neck of the femur after hip replacement, and electrical stimulation placed in the neck of the femur may resist this density loss to a certain extent. The rate of bone mineral density reduction decreased after the addition of electrical stimulation, indicating that electrical stimulation can have a certain resistance to the density reduction caused by stress shielding, and this result is helpful for the rehabilitation of hip arthroplasty. Full article

Background: Regeneration in the case of major burn subjects must involve tissue and structural regeneration, but also functional regeneration, as scars derived from burns often compromise motility. Electromagnetic fields and electrical stimulation may be a possible treatment for these cases, considering they cause a thermal effect and magneto-mechanical transduction first and selective tissue stimulation second. Methods: A case of a majorly burned woman with severe motor deficits, treated with electromagnetic fields and electrical stimulation in vacuum, associated with a personalized nutritional program, was described. The latter was necessary to favor weight loss with the preservation of the weakened structure. Ultrasonography, Doppler ultrasound, and body composition were measured. Moreover, postural evaluation was performed. Results: Immediately after the treatment, a restructuring of all tissue was seen. After 6 months, the tissue regeneration was evident, with neo-angiogenesis. From the functional point of view, her motility improved, and she stopped using a walker. Conclusions: The combined therapy allows her to obtain unthinkable results in a short time. For this reason, it could become the elective treatment for major burn scars. Full article

Chronic wounds pose a significant healthcare challenge due to their risk of severe complications, necessitating effective management strategies. Bioresorbable materials have emerged as an innovative solution, offering advantages such as eliminating the need for secondary surgical removal, reducing infection risks, and enabling time-delayed drug delivery. This review examines recent advancements in bioresorbable wound healing materials, focusing on a systematic review of bioresorbable materials, systems incorporating electrical stimulation, and drug delivery technologies to accelerate tissue repair. The discussion encompasses the fundamental principles of bioresorbable materials, including their resorption mechanisms and key properties, alongside preclinical applications that demonstrate their practical potential. Critical challenges impeding widespread adoption are addressed, and prospects for integrating these cutting-edge systems into clinical practice are outlined. Together, these insights underscore the promise of bioresorbable materials in revolutionizing chronic wound care. Full article

Proof-of-concept to determine the direct biomechanical effects of cardiac contractility modulation (CCM) on living myocardial slices (LMS) from patients with end-stage heart failure (HF). Left ventricular LMS from patients with end-stage HF were produced and cultured in a biomimetic system with mechanical loading and electrical stimulation. CCM stimulation (80 mA, 40 ms delay, 21 ms duration) enhanced maximum contractile force (CCM: 1229 µN (587–2658) vs. baseline: 1066 µN (529–2128), p = 0.05) and area under the contractile curve (CCM: 297 (151–562) vs. baseline: 243 (129–464), p = 0.05) but did not significantly impact contractile duration, time to peak, or time to relaxation. Increasing CCM stimulation delay, duration, and amplitude resulted in a higher fraction of LMS with a positive inotropic response. Furthermore, CCM attenuated the negative force-frequency relationship in HF-LMS. CCM stimulation enhanced contractile force in HF-LMS. The fraction of LMS exerting a positive inotropic response to CCM increased with increasing delay, duration, and amplitude settings, suggesting that personalizing stimulation parameters could optimize the beneficial effects of CCM. CCM is a novel device-based therapy that may improve contractile function, ejection fraction, functional outcomes, and quality of life in patients with heart failure. However, continuous efforts are needed to identify true responders to CCM therapy, understand the exact mechanisms, and optimize the contractile response to CCM stimulation. The present study revealed that CCM enhanced the contractile force of HF-LMS in a stimulation setting-dependent manner, reaching a larger fraction of the myocardium while increasing delay, duration, and amplitude. This understanding may contribute to the individualization of CCM stimulation settings. Full article

Background: Reciprocal inhibition (RI) is a spinal reflex that controls posture and movement. The modulation of spinal RI represented by the H-reflex has been studied, before and after voluntary contraction and electrical nerve stimulation but not during voluntary, electrically induced muscle contraction or a combination of voluntary and electrically induced muscle contractions. This study investigates the effects of the ongoing voluntary isometric contraction, the electrically induced isometric contraction, and the combination of voluntary with electrically induced isometric contraction of the Tibialis Anterior (TA) muscle on spinal RI represented by Soleus H-reflex. Methods: Eighteen healthy adults participated. Soleus H-reflex and M-response were measured during four different conditions as follows: (1) at rest, (2) electrically induced isometric contraction of the TA, (3) voluntary isometric contraction of the TA with a 1 kg force, and (4) combined voluntary and electrically induced isometric contraction of the TA with a 1 kg force. Results: The ANOVA clearly demonstrated significant differences in Soleus H-reflex amplitude across the four recording conditions (F3,16, 17.28, p < 0.001). The amplitude at rest was significantly higher than during electrically induced isometric contraction, voluntary isometric contraction, and the combined contraction conditions (p < 0.05). Furthermore, the amplitude recorded during the electrically induced isometric contraction condition significantly surpassed that of voluntary isometric contraction and the combined contraction conditions (p < 0.05). Moreover, there was no significant difference between Soleus H-reflex amplitude recorded during voluntary isometric contraction and the combined voluntary isometric contraction and electrically induced isometric contraction (p < 0.87). The combined voluntary isometric contraction and electrically induced isometric contraction condition had a higher inhibitory effect on the Soleus H-reflex with no significant differences from voluntary isometric contraction. Moreover, both were significantly better than electrically induced isometric contraction (p = 0.05). In terms of Soleus H-reflex latency, there was no significant difference among all four conditions (p > 0.05), meaning Soleus H-reflex latency was not influenced by the conditions. Conclusions: RI can be best modulated by combining voluntary with electrically induced isometric muscle contractions. Full article

Geothermal energy has emerged as a cornerstone in renewable energy, delivering reliable, low-emission baseload electricity and heating solutions. This review bridges the current knowledge gap by addressing challenges and opportunities for engineers and scientists, especially those transitioning from other professions. It examines deep and shallow geothermal systems and explores the advanced technologies and skills required across various climates and environments. Transferable expertise in drilling, completion, subsurface evaluation, and hydrological assessment is required for geothermal development but must be adapted to meet the demands of high-temperature, high-pressure environments; abrasive rocks; and complex downhole conditions. Emerging technologies like Enhanced Geothermal Systems (EGSs) and closed-loop systems enable sustainable energy extraction from impermeable and dry formations. Shallow systems utilize near-surface thermal gradients, hydrology, and soil conditions for efficient heat pump operations. Sustainable practices, including reinjection, machine learning-driven fracture modeling, and the use of corrosion-resistant alloys, enhance well integrity and long-term performance. Case studies like Utah FORGE and the Geysers in California, US, demonstrate hydraulic stimulation, machine learning, and reservoir management, while Cornell University has advanced integrated hybrid geothermal systems. Government incentives, such as tax credits under the Inflation Reduction Act, and academic initiatives, such as adopting geothermal energy at Cornell and Colorado Mesa Universities, are accelerating geothermal integration. These advancements, combined with transferable expertise, position geothermal energy as a major contributor to the global transition to renewable energy. Full article

Background: Orthostatic hypotension can occur during acute spinal cord injury (SCI) and subsequently persist. We investigated whether a gait rehabilitation robot combined with functional electrical stimulation (FES) stabilizes hemodynamics during orthostatic stress in SCI. Methods: Six intermediate-phase SCI patients (five males and one female; mean age: 49.5 years; four with quadriplegia and two with paraplegia) participated. The participants underwent robotic training (RT), with a gait rehabilitation robot combined with FES, and tilt table training (TT). Hemodynamics were monitored using a laser Doppler flowmeter for the earlobe blood flow (EBF) and non-invasive blood pressure measurements. The EBF over time and the resting and exercise blood pressures were compared between each session. Adverse events were also evaluated. Results: The EBF change decreased in TT but increased in RT at the 0.5-min slope (p = 0.03). Similarly, the pulse rate change increased in TT but decreased in RT at the 1-min slope (p = 0.03). Systolic and mean blood pressures were slightly higher in RT than in TT but not significantly (p = 0.35; 0.40). No adverse events occurred in RT, but two TT sessions were incomplete due to dizziness. Conclusions: RT with FES can reduce symptoms during orthostatic stress in intermediate-phase SCI. Future studies require a larger number of cases to generalize this study. Full article

Background/Objective: Maintaining sufficient ankle joint range of motion (ROM) contributes to efficient movement in sports and daily activities. Static stretching (SS), while effective, demands significant time, highlighting the need for alternative, time-efficient approaches to improve ROM. Therefore, this study aimed to evaluate the effectiveness of combined intervention (CI) using neuromuscular electrical stimulation (NMES) and elastic tape versus SS. Methods: This randomized crossover trial was conducted in healthy university students. They underwent both interventions with a 1-week washout period. The CI entailed the application of elastic tape to the plantar surface of the foot coupled with NMES targeting the posterior lower leg muscles for 1 min. SS was administered for 5 min using a tilt table. Outcome measures included the dorsiflexion angle (DFA), finger-floor distance (FFD), straight leg raise (SLR) angle, plantar flexor strength (PFS), and knee flexor strength (KFS), assessed pre- and post-intervention. DFA was analyzed using equivalence testing with a predefined margin. Results: Both interventions yielded significant improvements in DFA, FFD, and SLR. The combination of NMES and elastic tape demonstrated equivalence to 5 min of SS in enhancing DFA. Neither intervention resulted in a significant reduction in PFS or KFS. Conclusions: The CI of NMES and elastic tape effectively and safely improves flexibility in a short time. Its time efficiency makes it a promising alternative to SS, especially for brief warm-ups or limited rehabilitation time. Further research should explore its long-term effects and broader applicability. Full article

To enhance the differentiation and maturation of cardiomyocytes derived from human induced pluripotent stem cells, we developed a bioreactor system that simultaneously imposes biophysical and biochemical stimuli on these committed cardiomyocytes. The cells were cultured within biohydrogels composed of the extracellular matrix extracted from goat ventricles and purchased rat-origin collagen, which were housed in the elastic PDMS culture chambers of the bioreactor. Elastic and flexible electrodes composed of PEDOT/PSS, latex, and graphene flakes were embedded in the hydrogels and chamber walls, allowing cyclic stretch and electrical pulses to be simultaneously and coordinately applied to the cultured cells. Furthermore, a dynamic analysis method employing the transverse forced oscillation theory of a cantilever was used to analyze and discriminate the subtype-specific beating behavior of the cardiomyocytes. It was found that myosin light chain 2v (MLC2v), a ventricular cell marker, was primarily upregulated in cells aggregated on the (+) electrode side, while cardiomyocytes with faint MLC2v but strong cardiac troponin T (cTNT) expression aggregated at the ground electrode (GND) side. mRNA analysis using rtPCR and the gel beating dynamics further suggested a subtype deviation on the different electrode sides. This study demonstrated the potential of our bioreactor system in enhancing cardiac differentiation and maturation, and it showed an intriguing phenomenon of cardiomyocyte subtype aggregation on different electrodes, which may be developed into a new method to enhance the maturation and separation of cardiomyocyte subtypes. Full article

Blockchain technology introduces significant advancements in demand-side management (DSM) by enabling decentralized, transparent, and secure data handling within energy systems. This study explores a blockchain-based approach aimed at improving electricity efficiency through enhanced DSM strategies. We present a comprehensive framework that integrates blockchain technology with real-time data analytics to optimize energy consumption, stimulate consumer participation, and support efficient energy utilization. The experimental analysis demonstrates that blockchain integration significantly strengthens DSM operations by reducing operational costs, increasing participation in demand response programs, and enhancing grid stability. The findings highlight the effectiveness and potential of the proposed approach as a forward-looking solution for energy management systems. Full article

Magnetic polymeric conduits are developing as revolutionary materials in regenerative medicine, providing exceptional benefits in directing tissue healing, improving targeted medication administration, and facilitating remote control via external magnetic fields. The present article offers a thorough examination of current progress in the design, construction, and functionalization of these hybrid systems. The integration of magnetic nanoparticles into polymeric matrices confers distinctive features, including regulated alignment, improved cellular motility, and targeted medicinal delivery, while preserving structural integrity. Moreover, the incorporation of multifunctional attributes, such as electrical conductivity for cerebral stimulation and optical characteristics for real-time imaging, expands their range of applications. Essential studies indicate that the dimensions, morphology, surface chemistry, and composition of magnetic nanoparticles significantly affect their biocompatibility, degrading characteristics, and overall efficacy. Notwithstanding considerable advancements, issues concerning long-term biocompatibility, biodegradability, and scalability persist, in addition to the must for uniform regulatory frameworks to facilitate clinical translation. Progress in additive manufacturing and nanotechnology is overcoming these obstacles, facilitating the creation of dynamic and adaptive conduit structures designed for particular biomedical requirements. Magnetic polymeric conduits, by integrating usefulness and safety, are set to transform regenerative therapies, presenting a new avenue for customized medicine and advanced healthcare solutions. Full article