Matching Items (5)
Filtering by

Clear all filters

156692-Thumbnail Image.png
Description
The purpose of this dissertation was 1) to develop noninvasive strategies to assess skeletal muscle size, architecture, and composition in young and old adults (study #1) and 2) evaluate the impact of chemotherapeutic treatment on skeletal muscle satellite cells and capillaries (study #2). For study #1 ultrasound images were obtained

The purpose of this dissertation was 1) to develop noninvasive strategies to assess skeletal muscle size, architecture, and composition in young and old adults (study #1) and 2) evaluate the impact of chemotherapeutic treatment on skeletal muscle satellite cells and capillaries (study #2). For study #1 ultrasound images were obtained from the quadriceps muscles of young (8 m, 8 f) and older (7 m, 5 f) participants on two occasions, separated by 5-15 days. Images were collected while the participants were both standing and supine, and were analyzed for muscle thickness, pennation angle, and echogenicity. In addition, test-retest reliability and ICCs were evaluated for each posture and when imaging sites remained marked or were re-measured from visit #1 to visit #2. Generally, in both younger and older adults muscle thickness was greater and echogenicity was lower in the anterior quadriceps when images were collected standing versus supine. Maintaining the imaging site between visits did not influence test re-test reliability for either age group. Older adults exhibited smaller muscle thickness, lower pennation angle and increased echogenicity. Further, variability for the use of ultrasound to determine muscle thickness and pennation angle was greater in older versus younger adults. Findings from study #1 highlight several methodological considerations for US-based assessment of skeletal muscle characteristics that should be considered for improving reproducibility and generalizability of US to assess skeletal muscle characteristics and function across the aging spectrum. This is particularly relevant given the emerging use of ultrasound to assess skeletal muscle characteristics in healthy and clinical populations. In the second study, ovariectomized female Sprague-Dawley rats were randomized to receive three bi-weekly intraperitoneal injections of the chemotherapeutic drug, Doxorubicin (DOX) (4mg/kg; cumulative dose 12mg/kg) or vehicle (VEH; saline). Animals were euthanized 5d following the last injection, and the soleus (SOL) and extensor digitorum longus (EDL) muscles were dissected and prepared for immunohistochemical and RT-qPCR analyses. Relative to VEH, cross-sectional area (CSA) of the SOL and EDL muscle fibers were 26% and 33% smaller, respectively, in DOX animals (P<0.05). In the SOL satellite cell and capillary densities were 39% and 35% lower, respectively, in DOX animals (P<0.05), whereas in the EDL satellite cell and capillary densities were unaffected by DOX administration (P>0.05). In the SOL MYF5 mRNA expression was increased in DOX animals (P<0.05), while in the EDL MGF mRNA expression was reduced in DOX animals (P<0.05). Chronic DOX administration is associated with reduced fiber size in multiple skeletal muscles, however DOX appears to impact the satellite cell and capillary densities in a muscle-specific manner. These findings from study #2 highlight that therapeutic targets to protect skeletal muscle from DOX may vary across muscles. Collectively, these findings 1) improve the ability to examine muscle size and function in younger and older adults, and 2) identify promising therapeutic targets to protect skeletal muscle from the harmful effects of chemotherapy treatment.
ContributorsD'Lugos, Andrew (Author) / Dickinson, Jared M (Thesis advisor) / Buman, Matthew P (Committee member) / Gaesser, Glenn A (Committee member) / Huentelman, Matthew J (Committee member) / Katsanos, Christos S (Committee member) / Arizona State University (Publisher)
Created2018
154794-Thumbnail Image.png
Description
The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high in fat and sugar have been implicated in the pathogenesis of diabetes and cardiovascular disease. Exercise aids in the prevention

The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high in fat and sugar have been implicated in the pathogenesis of diabetes and cardiovascular disease. Exercise aids in the prevention of weight/fat gain, and prevents deleterious changes in cardiometabolic function. The objective of this study was to examine the effects of a fat-sugar supplemented diet, with and without two different exercise training protocols, on body composition, glycemic control and other markers of cardiovascular disease in an at-risk population of overweight and obese males. Twenty-seven, healthy overweight/obese (BMI >25 kg/m2) males were fed 2 donuts per day, 6 days/week, for four weeks, while maintaining their current diet. In addition, all subjects were randomized to one of the following conditions: sedentary control, 1,000 kcal/week moderate-intensity continuous training (MICT) (50% of peak oxygen consumption), or 1,000 kcal/week high-intensity interval training (HIIT) (90-95% of peak heart rate). Supervised exercise training was performed 4 days/week on a cycle ergometer. Changes in body weight and composition, endothelial function, arterial stiffness, glycemic control, blood lipids and cardiorespiratory fitness (CRF) were assessed before and after the intervention. Body weight, lean mass and visceral fat increased significantly in HIIT (p<0.05) and were unchanged in MICT. There was a trend for a significant increase in body weight (p=0.07) and lean mass (p=0.11) in control. Glycemic control during the 2-h OGTT improved significantly in MICT and control, with no change in HIIT. Hepatic insulin resistance index (IRI) and 30-min insulin during the OGTT improved significantly after MICT and worsened following control (p=0.03), while HIIT was unchanged. CRF increased significantly in both HIIT and MICT, with no change in control (p<0.001). There were no significant changes in other markers of cardiovascular disease. The addition of a fat-sugar supplement (~14,500 kcal) over a 4-week period was not sufficient to induce deleterious changes in body composition and cardiometabolic health in overweight/obese young males. Exercise training did not afford overweight/obese males additional health benefits, with the exception of improvements in fitness and hepatic IRI.
ContributorsTucker, Wesley Jack (Author) / Gaesser, Glenn A (Thesis advisor) / Angadi, Siddhartha S (Committee member) / Whisner, Corrie M (Committee member) / Buman, Matthew P (Committee member) / Shaibi, Gabriel (Committee member) / Arizona State University (Publisher)
Created2016
147696-Thumbnail Image.png
Description

This thesis project focuses on the effects of technology issues in the remote work environment and analyzes them using Bolman and Deal’s four frames for organizational leadership (2017). Real life examples of problems and solutions from the North America Laundry & Home Care Finance department at Henkel are utilized. An

This thesis project focuses on the effects of technology issues in the remote work environment and analyzes them using Bolman and Deal’s four frames for organizational leadership (2017). Real life examples of problems and solutions from the North America Laundry & Home Care Finance department at Henkel are utilized. An introduction to the scope of remote work in 2020 and 2021 is presented, followed by a description of Henkel’s role, size, and structure. Technology issues that occur while working remotely are described and looked at through different employee perspectives and leadership frames. Solutions currently in use and potential solutions to reduce any negative effects of these problems are also given.

ContributorsBlake, Quinn Patricia (Author) / deLusé, Stephanie (Thesis director) / Martucci, Megan (Committee member) / Department of Information Systems (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
161411-Thumbnail Image.png
Description
The health benefits of sufficient moderate-to-vigorous physical activity (MVPA) and sleep arewell-supported, with established links to decreased cancer risk, cardiometabolic health, all-cause mortality, and psychiatric symptomatology—including stress-related phenomena—for those who engage in 150 min MVPA/week and get at least 7 hours sleep/night. The latter outcome has rapidly become a major

The health benefits of sufficient moderate-to-vigorous physical activity (MVPA) and sleep arewell-supported, with established links to decreased cancer risk, cardiometabolic health, all-cause mortality, and psychiatric symptomatology—including stress-related phenomena—for those who engage in 150 min MVPA/week and get at least 7 hours sleep/night. The latter outcome has rapidly become a major public health concern as our nation grapples with the impact of prolonged COVID-19 pandemic stress, which has triggered an onslaught of depression, anxiety, and PTSD throughout the population. Thus, while strategies to decrease stress are desperately needed, many Americans fall short of the very MVPA and sleep recommendations that have been shown to increase their capacity to cope. The purpose of the present study was to explore time-varying associations of MVPA and sleep with momentary perceived stress in adults forced to work from home due to the COVID-19 pandemic. Thirty remote-working adults (86.7% women; mean age 37.5 years, SD = 10.4 years) wore GENEActiv accelerometers on the wrist to capture MVPA and sleep data, and answered four Ecological Momentary Assessments (EMAs) per day regarding perceived stress, for fourteen days straight. Between- and within-person variations in MVPA, sleep quality rating (SQR), total sleep time (TST), and sleep efficiency (SE) were analyzed via multilevel models to determine whether certain changes in these parameters might lead to decreased perceived momentary stress. Between-person models revealed a significant negative effect of SQR on perceived stress levels the next day, beta= -.651, SE= .303, P= .04. Mean MVPA, TST, and SE were not significant inter-individual predictors of momentary stress. However, within persons, higher than normal MVPA (beta= -.005, SE= .002, P= .015), SQR (beta= -.277, SE= .071, P <.001), TST (beta= -.001, SE= .000, P = .004), and SE (beta= -.524, SE= .242, P = .031) were all associated with significant decreases in momentary stress, with individuals experiencing incremental benefits with each additional minute of MVPA and TST. In conclusion, daily fluctuations in MVPA and sleep habits correlate more strongly with momentary stress than do typical levels of these behaviors; this presents an attainable strategy for individuals to enhance their capacity to cope.
ContributorsLyons, Rachel Crosley (Author) / Buman, Matthew P (Thesis advisor) / Der Ananian, Cheryl (Committee member) / McCracken, Kasondra (Committee member) / Arizona State University (Publisher)
Created2021
187604-Thumbnail Image.png
Description
Parkinson's Disease (PD) is a progressive neurodegenerative disorder that affects movement and balance control. Falls are a common and often debilitating consequence of PD, and reactive balance control is critical in preventing falls. This dissertation aimed to determine the adaptability and neural control of reactive balance responses in people with

Parkinson's Disease (PD) is a progressive neurodegenerative disorder that affects movement and balance control. Falls are a common and often debilitating consequence of PD, and reactive balance control is critical in preventing falls. This dissertation aimed to determine the adaptability and neural control of reactive balance responses in people with PD. Aim 1 investigated whether people with PD at risk for falls can improve their reactive balance responses through a 2-week, 6-session training protocol. The study found that reactive step training resulted in immediate and retained improvements in stepping, as measured by the anterior-posterior margin of stability (MOS), step length, and step latency during backward stepping. The second aim explored the neural mechanisms behind eliciting and learning reactive balance responses in PD. The study investigated the white matter (WM) correlates of reactive stepping and responsiveness to step training in PD. White matter was not significantly correlated with any baseline stepping outcomes. However, greater retention of step length was associated with increased fractional anisotropy (FA) within the left anterior corona radiata, left posterior thalamic radiation, and right and left superior longitudinal fasciculi. Lower radial diffusivity (RD) within the left posterior and anterior corona radiata were associated with retention of step latency improvements. These findings highlight the importance of WM microstructural integrity in motor learning and retention processes in PD. The third aim examined the role of the somatosensory system in reactive balance control in people with PD. The tactile and proprioceptive systems were perturbed using vibrotactile stimulation during backward feet-in-place balance responses. The results showed that tactile and proprioceptive stimulation had minimal impact on reactive balance responses. Small effects were observed for delayed tibialis anterior (TA) onsets with proprioceptive stimulation at a medium intensity. Overall, this dissertation provides insights into improving reactive balance responses and the underlying neural mechanisms in PD, which can potentially inform the development of targeted interventions to reduce falls in people with PD.
ContributorsMonaghan, Andrew S (Author) / Peterson, Daniel S (Thesis advisor) / Ofori, Edward (Committee member) / Daliri, Ayoub (Committee member) / Buman, Matthew P (Committee member) / Fling, Brett W (Committee member) / Arizona State University (Publisher)
Created2023