Rehabilitation and Therapy Commons^™

Long-Lasting Impairments In Quadriceps Mitochondrial Health, Muscle Size, And Phenotypic Composition Are Present After Non-Invasive Anterior Cruciate Ligament Injury, Steven M. Davi, Ahram Ahn, Mckenzie S. White, Timothy A. Butterfield, Kate Kosmac, Oh Sung Kwon, Lindsey K. Lepley

Center for Muscle Biology Faculty Publications

Introduction: Despite rigorous rehabilitation aimed at restoring muscle health, anterior cruciate ligament (ACL) injury is often hallmarked by significant long-term quadriceps muscle weakness. Derangements in mitochondrial function are a common feature of various atrophying conditions, yet it is unclear to what extent mitochondria are involved in the detrimental sequela of quadriceps dysfunction after ACL injury. Using a preclinical, non-invasive ACL injury rodent model, our objective was to explore the direct effect of an isolated ACL injury on mitochondrial function, muscle atrophy, and muscle phenotypic transitions.

Methods: A total of 40 male and female, Long Evans rats (16-week-old) were exposed to …

Evaluating The Microbiome To Boost Recovery From Stroke: The Embrs Study, Tyler Hammond

Theses and Dissertations--Neuroscience

Accumulating evidence suggests that gut microbes modulate brain plasticity via the bidirectional gut-brain axis and may play a role in stroke rehabilitation. A severely imbalanced microbial community has been shown to occur following stroke, causing a systemic flood of neuro- and immunomodulatory substances due to increased gut permeability and decreased gut motility. Here we measure post-stroke increased gut dysbiosis and how it correlates with gut permeability and subsequent cognitive impairment.

We recruited 12 participants with acute stroke, 12 healthy control participants, and 18 participants who had risk factors for stroke, but had not had a stroke. We measured the gut …

Myonuclear Transcriptional Dynamics In Response To Exercise Following Satellite Cell Depletion, Yuan Wen, Davis A. Englund, Bailey D. Peck, Kevin A. Murach, John J. Mccarthy, Charlotte A. Peterson

Physical Therapy Faculty Publications

Skeletal muscle is composed of post-mitotic myofibers that form a syncytium containing hundreds of myonuclei. Using a progressive exercise training model in the mouse and single nucleus RNA-sequencing (snRNA-seq) for high-resolution characterization of myonuclear transcription, we show myonuclear functional specialization in muscle. After 4 weeks of exercise training, snRNA-seq reveals that resident muscle stem cells, or satellite cells, are activated with acute exercise but demonstrate limited lineage progression while contributing to muscle adaptation. In the absence of satellite cells, a portion of nuclei demonstrates divergent transcriptional dynamics associated with mixed-fate identities compared with satellite cell replete muscles. These data provide …

Gait And Balance Changes With Investigational Peripheral Nerve Cell Therapy During Deep Brain Stimulation In People With Parkinson’S Disease, Geetanjali Gera, Zain Guduru, Tritia R. Yamasaki, Julie A. Gurwell, Monica Chau, Anna Krotinger, Frederick A. Schmitt, John T. Slevin, Greg A. Gerhardt, Craig G. Van Horne, Jorge E. Quintero

Physical Therapy Faculty Publications

Background: The efficacy of deep brain stimulation (DBS) and dopaminergic therapy is known to decrease over time. Hence, a new investigational approach combines implanting autologous injury-activated peripheral nerve grafts (APNG) at the time of bilateral DBS surgery to the globus pallidus interna. Objectives: In a study where APNG was unilaterally implanted into the substantia nigra, we explored the effects on clinical gait and balance assessments over two years in 14 individuals with Parkinson’s disease. Methods: Computerized gait and balance evaluations were performed without medication, and stimulation was in the off state for at least 12 h to best assess the …

Cardiorespiratory Fitness Diminishes The Effects Of Age On White Matter Hyperintensity Volume, Nathan F. Johnson, Ahmed A. Bahrani, David K. Powell, Gregory A. Jicha, Brian T. Gold

Physical Therapy Faculty Publications

White matter hyperintensities (WMHs) are among the most commonly observed marker of cerebrovascular disease. Age is a key risk factor for WMH development. Cardiorespiratory fitness (CRF) is associated with increased vessel compliance, but it remains unknown if high CRF affects WMH volume. This study explored the effects of CRF on WMH volume in community-dwelling older adults. We further tested the possibility of an interaction between CRF and age on WMH volume. Participants were 76 adults between the ages of 59 and 77 (mean age = 65.36 years, SD = 3.92) who underwent a maximal graded exercise test and structural brain …

Non-Fasting High-Density Lipoprotein Is Associated With White Matter Microstructure In Healthy Older Adults, Nathan F. Johnson, Brian T. Gold, Dorothy Ross, Alison L. Bailey, Jody L. Clasey, Vedant Gupta, Steve W. Leung, David K. Powell

Physical Therapy Faculty Publications

A growing body of evidence indicates that biomarkers of cardiovascular risk may be related to cerebral health. However, little is known about the role that non-fasting lipoproteins play in assessing age-related declines in a cerebral biomarker sensitive to vascular compromise, white matter (WM) microstructure. High-density lipoprotein cholesterol (HDL-C) is atheroprotective and low-density lipoprotein cholesterol (LDL-C) is a major atherogenic lipoprotein. This study explored the relationships between non-fasting levels of cholesterol and WM microstructure in healthy older adults. A voxelwise and region of interest approach was used to determine the relationship between cholesterol and fractional anisotropy (FA). Participants included 87 older …

Changes In Muscle Size, Quality And Power Are Related To Physical Function In Patients With Critical Illness, Kirby Mayer

Theses and Dissertations--Rehabilitation Sciences

Patients admitted to intensive care unit (ICU) are known to develop significant impairments in physical function. Patients with critical illness suffer up to 30% reductions in muscle size within the first ten days of admission to the ICU. Muscle strength testing, Medical Research Council-sum score, is current gold-standard to diagnosis ICU-acquired weakness and predicts risk of mortality and long-term physical function. Muscle power different from muscle strength in that it accounts for velocity of movement, is potentially a better independent predictor of function that has not been studied in this population. In addition, we hypothesize that muscle size and quality …

Muscle Synergy During A Single Leg Standing Test In Ambulatory Children With Cerebral Palsy, Brennan L. Smith

Theses and Dissertations--Kinesiology and Health Promotion

INTRODUCTION: Cerebral Palsy (CP) is a sensorimotor disorder characterized by dysfunctional motor coordination, balance problems, and loss of selective motor control. Motor coordination exhibited as co-contraction, has been subjectively quantified using gait analysis, but recent studies have begun to objectively analyze the amount of co-contraction by collecting electromyography (EMG) data. Center of pressure excursion (COPE) measurements collected during a single leg standing test (SLST) have shown to be more valid measurements of balance in populations with motor disabilities than a SLST alone. A recent study has correlated increased COPE velocity with a lower fall risk as determined by reported fall …

Endothelial Function Is Associated With White Matter Microstructure And Executive Function In Older Adults, Nathan F. Johnson, Brian T. Gold, Christopher A. Brown, Emily F. Anggelis, Alison L. Bailey, Jody L. Clasey, David K. Powell

Physical Therapy Faculty Publications

Age-related declines in endothelial function can lead to cognitive decline. However, little is known about the relationships between endothelial function and specific neurocognitive functions. This study explored the relationship between measures of endothelial function (reactive hyperemia index; RHI), white matter (WM) health (fractional anisotropy, FA, and WM hyperintensity volume, WMH), and executive function (Trail Making Test (TMT); Trail B - Trail A). Participants were 36 older adults between the ages of 59 and 69 (mean age = 63.89 years, SD = 2.94). WMH volume showed no relationship with RHI or executive function. However, there was a positive relationship between RHI …

Development, Validation And Application Of A New Fornix Template For Studies Of Aging And Preclinical Alzheimer's Disease, Christopher A. Brown, Nathan F. Johnson, Amelia J. Anderson-Mooney, Gregory A. Jicha, Leslie M. Shaw, John Q. Trojanowski, Linda J. Van Eldik, Frederick A. Schmitt, Charles D. Smith, Brian T. Gold

Physical Therapy Faculty Publications

We developed a merged younger-older adult template of the fornix and demonstrated its utility for studies of aging and preclinical Alzheimer's disease (AD). In Experiment 1, probabilistic tractography was used to reconstruct the fornix in younger and older adults and successful streamlines were then averaged to create a merged template in standard space. The new template includes the majority of the fornix from the hippocampal formation to the subcallosal region and the thalamus/hypothalamus. In Experiment 2, the merged template was validated as an appropriate measure for studies of aging, with comparisons against manual tracing measures indicating identical spatial coverage in …

Mitochondria-Associated Micrornas In Rat Hippocampus Following Traumatic Brain Injury, Wang-Xia Wang, Nishant P. Visavadiya, Jignesh D. Pandya, Peter T. Nelson, Patrick G. Sullivan, Joe E. Springer

Sanders-Brown Center on Aging Faculty Publications

Traumatic brain injury (TBI) is a major cause of death and disability. However, the molecular events contributing to the pathogenesis are not well understood. Mitochondria serve as the powerhouse of cells, respond to cellular demands and stressors, and play an essential role in cell signaling, differentiation, and survival. There is clear evidence of compromised mitochondrial function following TBI; however, the underlying mechanisms and consequences are not clear. MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally, and function as important mediators of neuronal development, synaptic plasticity, and neurodegeneration. Several miRNAs show altered expression following TBI; however, the …