Spasticity attributable to exaggerated stretch reflex pathways, particularly affecting the ankle plantar flexors, often impairs overground walking in persons with incomplete spinal cord injury. Compelling evidence from rodent models underscores how exposure to acute intermittent hypoxia (AIH) can provide a unique medium to induce spinal plasticity in key inhibitory pathways mediating stretch reflex excitability and potentially affect spasticity. In this study, we quantify the effects of a single exposure to AIH on the stretch reflex in able-bodied individuals.
View Article and Find Full Text PDFUnlabelled: Brief episodes of low oxygen breathing (therapeutic acute intermittent hypoxia; tAIH) may serve as an effective plasticity-promoting primer to enhance the effects of transcutaneous spinal stimulation-enhanced walking therapy (WALK) in persons with chronic (>1 year) spinal cord injury (SCI). Pre-clinical studies in rodents with SCI show that tAIH and WALK therapies harness complementary mechanisms of plasticity to maximize walking recovery. Here, we present a multi-site clinical trial protocol designed to examine the influence of tAIH + WALK on walking recovery in persons with chronic SCI.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
January 2024
Individuals with spinal cord injury (SCI) have significant dysfunction in cardiovascular autonomic regulation. Although recent findings postulate that spinal cord stimulation improves autonomic regulation, limited scope of past methods have tested only above level sympathetic activation, leaving significant uncertainty. To identify whether transcutaneous spinal cord stimulation improves cardiovascular autonomic regulation, two pairs of well-matched individuals with and without high thoracic, complete SCI were recruited.
View Article and Find Full Text PDFPurpose: Patients with end-stage renal disease (ESRD) on hemodialysis (HD) are considered particularly susceptible to infection with SARS-CoV2 on the basis of the immunodeficiency associated with advanced age, comorbidity burden, medication use, and need for frequent visits to dialysis clinics. In prior studies, thymalfasin (thymosin alpha 1, Ta1) has been shown to enhance antibody response to influenza vaccine and reduce influenza infection in geriatric populations, including hemodialysis patients, when used as an adjunct to influenza vaccine. Early in the COVID-19 pandemic we speculated that administration of Ta1 to HD patients would result in reduced rate and severity of COVID-19 infection.
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