Noninvasive Electrical Modalities to Alleviate Respiratory Deficits Following Spinal Cord Injury.

(1) Background: Respiratory dysfunction is a debilitating consequence of cervical and thoracic spinal cord injury (SCI), resulting from the loss of cortico-spinal drive to respiratory motor networks. This impairment affects both central and peripheral nervous systems, disrupting motor control and muscle innervation, which is essential for effective breathing. These deficits significantly impact the health and quality of life of individuals with SCI.

Spinal Neuromodulation for Respiratory Rehabilitation in Patients with Post-Acute COVID-19 Syndrome.

(1) Background: Neurological deficits associated with coronavirus disease (COVID-19) exacerbate respiratory dysfunction, necessitating rehabilitation strategies that address both. Previous studies have demonstrated that spinal cord transcutaneous stimulation (scTS) can facilitate the excitation of respiratory spinal neural networks in patients with post-COVID-19 syndrome. This study evaluates the efficacy of combining scTS with respiratory training (RT) to improve respiratory function in individuals with post-COVID-19 pulmonary deficits; (2) Methods: In this before-after, case-controlled clinical trial, five individuals with post-acute COVID-19 respiratory deficits participated in two interventional programs: 10 daily sessions of respiratory training (RT), followed by 10 daily sessions of scTS combined with RT (scTS + RT).

Plasma ionization balance in chemical-picture and average-atom models.

We propose an approximate method to calculate ion partition functions in the context of the chemical-picture representation of plasmas as an interacting mixture of various ions and free electrons under the local-thermodynamic-equilibrium conditions. The method uses the superconfiguration approach and implies that the first-order corrections to the energies of excited electron configurations due to the electron-electron interaction may be replaced by a similar first-order correction to the energy of the basic configuration of an ion with the same number of bound electrons. The method enables one to significantly speed up the calculations and generally provides quite accurate results.

Transcutaneous Spinal Cord Stimulation Facilitates Respiratory Functional Performance in Patients with Post-Acute COVID-19.

Background: A growing number of studies have reported Coronavirus disease (COVID-19) related to both respiratory and central nervous system dysfunctions. This study evaluates the neuromodulatory effects of spinal cord transcutaneous stimulation (scTS) on the respiratory functional state in healthy controls and patients with post-COVID-19 respiratory deficits as a step toward the development of a rehabilitation strategy for these patients.

Methods: In this before-after, interventional, case-controlled clinical study, ten individuals with post-acute COVID-19 respiratory deficits and eight healthy controls received a single twenty-minute-long session of modulated monophasic scTS delivered over the T5 and T10 spinal cord segments.

ECG Markers of Acute Melatonin Treatment in a Porcine Model of Acute Myocardial Ischemia.

In myocardial ischemia, melatonin confers antiarrhythmic action, but its electrocardiographic expression is unclear. We aimed to evaluate the effects of melatonin treatment on electrocardiogram (ECG) parameters reflecting major arrhythmogenic factors and to test the association of these parameters with ventricular fibrillation (VF) incidence. Myocardial ischemia was induced by 40 min coronary artery occlusion in 25 anesthetized pigs.

Novel Noninvasive Spinal Neuromodulation Strategy Facilitates Recovery of Stepping after Motor Complete Paraplegia.

It has been suggested that neuroplasticity-promoting neuromodulation can restore sensory-motor pathways after spinal cord injury (SCI), reactivating the dormant locomotor neuronal circuitry. We introduce a neuro-rehabilitative approach that leverages locomotor training with multi-segmental spinal cord transcutaneous electrical stimulation (scTS). We hypothesized that scTS neuromodulates spinal networks, complementing the neuroplastic effects of locomotor training, result in a functional progression toward recovery of locomotion.

Equation of state modeling with pseudoatom molecular dynamics.

Using a modified version of the pseudoatom molecular-dynamics approach, the silicon and oxygen equations of state were generated and then employed to construct the equation of state of silicon dioxide. The results are supported by the close agreement with ab initio simulations of the silicon pressure and experimental shock Hugoniot of silicon dioxide. Ion thermal contributions to thermodynamic functions provided by the PAMD simulations are compared to their counterparts obtained with the one-component plasma and charged-hard-sphere approximations.

Prolongation of experimental diabetes mellitus increased susceptibility to reperfusion ventricular tachyarrhythmias.

Diabetes mellitus (DM) is associated with increased risk of sudden cardiac death, but its role in arrhythmogenesis is not clear. We evaluated contributions of DM duration and hyperglycemia level to development of proarrhythmic electrophysiological changes in the experimental ischemia/reperfusion model. Ventricular epicardial 64-lead mapping and arrhythmia susceptibility burst-pacing testing were performed in 43 healthy and 55 diabetic (alloxan model) anesthetized rabbits undergoing 15 min left anterior descending coronary artery occlusion, followed by 15 min reperfusion.

Clinical Trial Designs for Neuromodulation in Chronic Spinal Cord Injury Using Epidural Stimulation.

Study Design: This is a narrative review focused on specific challenges related to adequate controls that arise in neuromodulation clinical trials involving perceptible stimulation and physiological effects of stimulation activation.

Objectives: 1) To present the strengths and limitations of available clinical trial research designs for the testing of epidural stimulation to improve recovery after spinal cord injury. 2) To describe how studies can control for the placebo effects that arise due to surgical implantation, the physical presence of the battery, generator, control interfaces, and rehabilitative activity aimed to promote use-dependent plasticity.

Melatonin Prevents Early but Not Delayed Ventricular Fibrillation in the Experimental Porcine Model of Acute Ischemia.

Antiarrhythmic effects of melatonin have been demonstrated ex vivo and in rodent models, but its action in a clinically relevant large mammalian model remains largely unknown. Objectives of the present study were to evaluate electrophysiological and antiarrhythmic effects of melatonin in a porcine model of acute myocardial infarction. Myocardial ischemia was induced by 40-min coronary occlusion in 25 anesthetized pigs.

Prolonged Targeted Cardiovascular Epidural Stimulation Improves Immunological Molecular Profile: A Case Report in Chronic Severe Spinal Cord Injury.

In individuals with severe spinal cord injury (SCI), the autonomic nervous system (ANS) is affected leading to cardiovascular deficits, which include significant blood pressure instability, with the prevalence of systemic hypotension and orthostatic intolerance resulting in an increased risk of stroke. Additionally, persons with SCI rostral to thoracic vertebral level 5 (T5), where sympathetic nervous system fibers exit the spinal cord and innervate the immune system, have clinically significant systemic inflammation and increased infection risk. Our recent studies show that lumbosacral spinal cord epidural stimulation (scES), applied at the lumbosacral level using targeted configurations that promote cardiovascular stability (CV-scES), can safely and effectively normalize blood pressure in persons with chronic SCI.

Contribution of Depolarization and Repolarization Changes to J-Wave Generation and Ventricular Fibrillation in Ischemia.

: Activation delay in ischemic myocardium has been found to contribute to J-wave appearance and to predict ventricular fibrillation (VF) in experimental myocardial infarction. However, the role of ischemia-related repolarization abnormalities in J-wave generation remains unclear. : The objective of our study was to assess a contribution of myocardial repolarization changes to J-wave generation in the body surface ECG and VF in a porcine acute myocardial infarction model.

Heart rate and blood pressure response improve the prediction of orthostatic cardiovascular dysregulation in persons with chronic spinal cord injury.

Unstable blood pressure after spinal cord injury (SCI) is not routinely examined but rather predicted by level and completeness of injury (i.e., American Spinal Injury Association Impairment Scale AIS classification).

Cardiovascular Autonomic Dysfunction in Spinal Cord Injury: Epidemiology, Diagnosis, and Management.

Spinal cord injury (SCI) disrupts autonomic circuits and impairs synchronistic functioning of the autonomic nervous system, leading to inadequate cardiovascular regulation. Individuals with SCI, particularly at or above the sixth thoracic vertebral level (T6), often have impaired regulation of sympathetic vasoconstriction of the peripheral vasculature and the splanchnic circulation, and diminished control of heart rate and cardiac output. In addition, impaired descending sympathetic control results in changes in circulating levels of plasma catecholamines, which can have a profound effect on cardiovascular function.

Preventive Administration of Melatonin Attenuates Electrophysiological Consequences of Myocardial Ischemia.

The effect of preventive administration of melatonin on the arrhythmogenic substrate in the myocardium was studied in the rabbit model of acute ischemia/reperfusion in vivo. The animals treated with melatonin 60 min before ischemia induction had shorter median activation time compared to the control group (p=0.039), less pronounced shortening of repolarization durations in the ischemic zone during coronary occlusion (p=0.

A wide-range multiphase equation of state for platinum.

The paper presents a semi-empirical wide-range equation of state (EOS) for platinum with account for melting, evaporation, and ionization. The equation is based on a wide spectrum of experimental and calculation data. Parameters for the EOS were adjusted using a genetic algorithm which proved to perform well for optimizations in big data processing.

Relationship among anesthesia technique, surgical stress, and cognitive dysfunction following spinal surgery: a randomized trial.

Objective: Surgical trauma is known to result in systemic inflammatory changes that can lead to postoperative cognitive dysfunction. In the present study, the authors compared the effects of an epidural anesthesia protocol to those of traditional anesthesia with regard to postoperative inflammatory changes, cellular immunity, and cognitive dysfunction.

Methods: Forty-eight patients, ages 45-60 years, underwent multilevel thoracolumbar decompression and fusion and were randomly assigned to one of two groups: group 1 (27 patients) had combined epidural and general anesthesia, followed by epidural analgesia for 48 hours after surgery, and group 2 (21 patients) had general anesthesia, followed by traditional opioid pain management after surgery.

Prolongation of The Activation Time in Ischemic Myocardium is Associated with J-wave Generation in ECG and Ventricular Fibrillation.

J-wave pattern has been recognized as an arrhythmic risk marker, particularly in myocardial infarction patients. Mechanisms underlying J-wave development in ischemia remain unknown. In myocardial infarction model, we evaluated activation time delay as a prerequisite of J-wave appearance and predictor of ventricular fibrillation.

Design, Development, and Characterization of BreathForce: A Respiratory Training System for Patients with Spinal Cord Injuries.

In this effort, we report the development of a portable inspiratory-expiratory training device for use in rehabilitation of participants with cardiovascular and respiratory motor deficits. The device uses existing airway restriction components to establish a manually adjustable respiratory training apparatus and includes an integrated pressure sensor with custom software to direct and track therapy sessions. The battery-powered system promotes proven rehabilitation methodologies performed at the clinic in a platform to be translated to the home for participants with spinal cord injuries.

Epidural Spinal Cord Stimulation Training and Sustained Recovery of Cardiovascular Function in Individuals With Chronic Cervical Spinal Cord Injury.

This cohort study evaluates the feasibility of daily customized epidural stimulation configurations targeted for cardiovascular function in individuals with chronic, cervical motor-complete spinal cord injury.

Respiratory muscle activation patterns during maximum airway pressure efforts are different in women and men.

Maximum inspiratory and expiratory pressure values (PI and PE) are indirect measures of respiratory muscle strength that, in healthy adults, are known to be significantly lower in women compared to men. In part, sex differences in breathing kinematics, lung size, body composition, muscle mass, and muscle fiber composition are thought to be responsible for these effects. However, it is not known whether respiratory muscle activation during maximum respiratory efforts is also sex-specific.

Strategies for the Integration of Cough and Swallow to Maintain Airway Protection in Humans.

Purpose: Airway protective behaviors, like cough and swallow, deteriorate in many populations suffering from neurologic disorders. While coordination of these behaviors has been investigated in an animal model, it has not been tested in humans.

Methods: We used a novel protocol, adapted from previous work in the cat, to assess cough and swallow independently and their coordination strategies in seven healthy males (26 ± 6 years).

Epidural Spinal Cord Stimulation of Lumbosacral Networks Modulates Arterial Blood Pressure in Individuals With Spinal Cord Injury-Induced Cardiovascular Deficits.

Disruption of motor and autonomic pathways induced by spinal cord injury (SCI) often leads to persistent low arterial blood pressure and orthostatic intolerance. Spinal cord epidural stimulation (scES) has been shown to enable independent standing and voluntary movement in individuals with clinically motor complete SCI. In this study, we addressed whether scES configured to activate motor lumbosacral networks can also modulate arterial blood pressure by assessing continuous, beat-by-beat blood pressure and lower extremity electromyography during supine and standing in seven individuals with C5-T4 SCI.