Tag: Human Physiology

Comparison of External Load Estimation from Wearable Sensors during a Free Run

Presenter: Anna Mare − Human Physiology

Faculty Mentor(s): Seth Donahue, Rachel Robinson

Session: (In-Person) Poster Presentation

Cumulative training load has been defined as the product of external loading and internal physiological loading experienced by an individual during a training session and may be an important predictor for running related injury. Traditional methods of monitoring external load for runners has been the tracking of mileage, however, with the increased availability of wearable sensors, we can develop more sophisticated paradigms for the estimation of external load. Inertial Measurement Units (IMUs) and GPS watches are wearable sensors that have been used for the quantification of external load during running in a laboratory setting. The purpose of this study was to compare GPS-derived metrics and IMU metrics for the quantification of ground reaction force (GRF) peaks as an estimation of external load from participants running in a real-world environment. Twelve participants were equipped with force sensing insoles to measure GRF. Three IMUs were mounted on each participant, one on the dorsal aspect of each foot, and one attached near the sacrum on the waistband. Participants also wore a Garmin GPS watch. Participants were instructed to run an approximately 5-mile course at their own pace. The IMU-based model was a significantly better fit than the GPS model, indicating an improvement of the estimation of external load using IMU data. These findings show that IMUs provide a more accurate estimation of cumulative peak GRF as a proxy for external load than GPS-derived estimates.

Ethnic Variations in Asian and Asian American Men’s Disordered Eating Symptoms

Presenter: Kevin Le – Human Physiology

Faculty Mentor(s): Claire Guidinger, Nichole Kelly

Session: (In-Person) Poster Presentation

Asian and Asian American men report high rates of disordered eating symptoms, such as body dissatisfaction. Some have hypothesized that these behaviors are a consequence of being stereotyped as petite, more feminine, and less attractive that their non-Asian peers. However, this theoretical and empirical research fails to recognize that there are substantial ethnic variations in both body sizes and cultural ideals among diverse Asian/Asian American populations. This study aimed to identify and clarify potential ethnic variations in Asian/Asian American men’s disordered eating symptoms. 179 Asian/Asian American men (18-30y; Mage=24.03±3.6) completed an online study that included measures of ethnic identity; height and weight; LOC eating (0 = absent, 1 = present); dieting; excessive exercise; body image concerns; and drive for muscularity. Ethnic subgroups included men who self-identified as Chinese (n = 59), Filipino (n = 33), Korean (n = 21), Vietnamese (n = 25), and Indian (n = 41). One-way ANOVAS indicated Asian ethnic subgroups only significantly differed in concerns with muscularity [F(4, 174) = 2.65, p<.05]. Post Hoc findings indicated that Filipino men endorsed significantly higher muscularity concerns compared to Vietnamese men, p<.05. Future research should seek to identify cultural factors that function as both risk and protective factors for disordered eating cognitions and behaviors in Filipino men, as well as other groups of Asian/Asian American men.

The effects of ovariectomy and soy diet on vascular function in female C57BL6 mice

Presenter: Aleena Khurana − Human Physiology

Faculty Mentor(s): Ashley Walker, Mackenzie Kehmeier

Session: (In-Person) Oral Panel—Stimuli and Response

As people begin to live longer, studying age-related disease becomes more important. Age is a major risk factor for Alzheimer’s disease (AD), a prominent neurodegenerative disease, and other cardiovascular diseases; Females develop AD at much higher rates and all signs point to sex hormones. Estrogen drastically decreases post menopause, and it has been suggested that estrogen deficiency is a contributing factor to the sex differences seen in AD and other age-related diseases. The vascular system plays an important role in aging. A characteristic of aging in the vascular system is stiffening of larger arteries. Large artery stiffening is detrimental due to the increase in pulse pressure and stress associated with stiffening. Decreased estrogen activity results in increased production of reactive oxygen species (ROS), causing tissue damage and dysfunction. Elevated ROS and oxidative stress increase inflammation in the brain, further explaining the potential effects estrogen loss has in relation to such diseases. Soy also has been seen to be a protective factor against symptoms of age-related disease due to its role as a phytoestrogen, thus showing the potential importance of soy. This study aimed to explore the effects of estrogen depletion post menopause and the effects of a soy diet in relation with estrogen loss. We utilized a mouse model including ovariectomies to mimic estrogen loss post menopause and studied cognitive function, motor coordination, and vascular function.

The Effectiveness of MRI in Diagnosing Osteoarthritis as Compared to Evaluative Cadaveric Dissection

Presenter: Katherine Kennedy − Human Physiology

Faculty Mentor(s): Jon Runyeon

Session: (In-Person) ) Oral Panel—Neuron & Cognition

Osteoarthritis (OA) is the leading cause for chronic disability in the U.S, affecting over 32 million adults nationwide. Although there is no cure for the age-related disease, early detection and diagnosis is crucial in providing individuals with treatment that will improve joint function, health, and overall quality of life. With what is often said to be the gold standard of OA diagnosis, Magnetic Resonance Imaging (MRI), researchers have studied the tool’s methodological accuracy through comparing it to other widely used instruments, such as X-rays. However, all imaging methods offer indirect visualization of the pathological condition, whereas analysis of the joint cartilage itself would offer a direct way of evaluating the disease. The purpose of this study was to assess MRI effectiveness in the diagnosis of osteoarthritis through visualization of common pathological features in the knee both indirectly, using MRI, and directly through evaluative dissection of the cadaveric knee joint. It is hypothesized that the observations and measurements drawn from the direct dissection of the joints will convey clearer indications of OA and the true grade of its severity more so than MRI will through the minimal OA evidence picked up indirectly through magnetic signals. This will dismiss MRI as the gold standard for OA diagnosis and will pave the way for future research on discovering new, effective methods for early detection and accurate diagnosis of the common joint disease.

Personal Training and its Effects on University of Oregon Students

Presenter: Jackson Hullinger − Human Physiology

Co-Presenter(s): Karl Schenk, Olivia Gurley

Faculty Mentor(s): Chantelle Russell

Session: (Virtual) Oral Panel—Strive to Thrive ARC

This paper analyzes how personal trainers affect and influence the wellness of college students at University of Oregon. If students work with personal trainers then their overall wellness will improve because working with a personal trainer offers a more structured workout plan for people who are inexperienced or uncomfortable at the gym, less risk of injury, and guidance on proper nutrition. To prove this, we read through multiple scientific research papers and spoke to various personal trainers and students about how personal training has benefitted them. Our primary results showed that among the people we interviewed, the overwhelming majority of participants showed improvements in their overall wellness. However, these results were based on prior experience in the gym and their individual relationship with their trainer. The implications of these results can help direct more students who are not comfortable with the gym and/or whose physical and mental health is not well to the Rec Center. Additional possible outcomes of this could be a raised GPA among students at UO, better physical and mental health of students, and just an overall better campus. Overall physical and mental wellness are important aspects of well that UO is trying to help students with, and directing students to meet with a personal trainer would be the most beneficial way to improve wellness.

Renal Hemodynamic Response to Oral Protein Loading during Prolonged Mild Hypohydration

Presenter: Sadie Holt − Human Physiology

Faculty Mentor(s): Dr. Christopher Chapman

Session: (In-Person) Poster Presentation

Hypohydration, a state of low body water, can occur due to inadequate fluid consumption or with sweating during heat stress. The kidneys regulate body water through multiple mechanisms including modulation of renal blood flow. It is not known if prolonged hypohydration alters the control of renal blood flow. Renal blood flow control can be probed using an oral protein load, a stimulus that increases renal blood flow within 1-3 hours. We tested the hypothesis that prolonged mild hypohydration attenuates oral protein loading-induced increases in renal blood flow compared to a hydrated state (i.e., euhydrated). Eight healthy adults (5 females) arrived at the lab after 24 hours of fluid deprivation (HYPO) or when euhydrated (EUHY). Subjects ingested a whey protein beverage to stimulate increases in renal blood flow. Doppler ultrasonography was used to estimate renal blood flow from blood velocity in the renal and segmental arteries. Data were summarized as the peak increase in renal blood velocity. A mild hypohydration was confirmed by greater reductions in body mass in HYPO vs. EUHY (HYPO: -2.2±0.5%; EUHY: -0.3±0.7%, P=0.001). There were no differences between conditions in the peak increase in renal (HYPO: +5.6±3.8 cm/s; EUHY: +4.8±3.3 cm/s, P=0.54) and segmental (HYPO: +4.4±4.7 cm/s; EUHY: +3.4±4.0 cm/s, P=0.43) artery blood velocities. These findings indicate that prolonged mild hypohydration does not alter the kidneys’ ability to increase renal blood flow.

Discovery of Affinity Binding Partners for Controlled Protein Delivery

Presenter: Henry Hochstatter − Human Physiology

Faculty Mentor(s): Jonathan Dorogin

Session: (In-Person) Poster Presentation

Wound healing is orchestrated by a complex sequence of proteins, including granulocyte-macrophage colony stimulating factor (GM-CSF), which facilitates myeloid stem cell differentiation into mature immune cells during the inflammatory response, and fibroblast growth factor-2 (FGF-2), which stimulates fibroblast proliferation. Delivery of these proteins to sites of injury may increase the efficacy of tissue repair, but current protein delivery methods fail to precisely control the temporal presentation of GM-CSF and FGF-2 at relevant stages of wound healing. The aim of this research is to develop affinity-based biomaterials that can facilitate the controlled delivery of these regenerative proteins for improved tissue regeneration. To accomplish this, small protein-binding peptides called affibodies have been identified from a randomized pool of ~860 million unique sequences via sorting of a yeast surface display library. Five affibodies were selected that specifically bind to GM-CSF or FGF-2 with varying affinities; the affinities of these affibodies have been characterized on the surface of yeast cells, and were expressed as soluble proteins in E. coli for further analysis. The wide range of affibody affinities for their protein targets will enable extensive modulation of temporal protein presentation. Conjugating these affibodies to biomaterials will allow for the spatiotemporal control of protein release to a wound site for improved wound healing in the clinic.

Personal training and the students at UO

Presenter: Olivia Gurley − Human Physiology

Co-Presenter(s): Jackson Hullinger, Karl Schenk

Faculty Mentor(s): Chantelle Russell

Session: (Virtual) Oral Panel—Strive to Thrive ARC

This paper analyzes how personal trainers affect and influence the wellness of college students at University of Oregon. If students work with personal trainers then their overall wellness will improve because working with a personal trainer offers a more structured workout plan for people who are inexperienced or uncomfortable at the gym, less risk of injury, and guidance on proper nutrition. To prove this, we read through multiple scientific research papers and spoke to various personal trainers and students about how personal training has benefitted them. Our primary results showed that among the people we interviewed, the overwhelming majority of participants showed improvements in their overall wellness. However, these results were based on prior experience in the gym and their individual relationship with their trainer. The implications of these results can help direct more students who are not comfortable with the gym and/or whose physical and mental health is not well to the Rec Center. Additional possible outcomes of this could be a raised GPA among students at UO, better physical and mental health of students, and just an overall better campus. Overall physical and mental wellness are important aspects of wellness that UO is trying to help students with, and directing students to meet with a personal trainer would be the most beneficial way to improve wellness.

Femoral Fracture Fixation Device to Wirelessly Monitor Real Time, in Vivo Strain

Presenter: Noah Greenblatt – Human Physiology

Co-Presenter(s): Walker Rosenthal

Faculty Mentor(s): Keat Ghee Ong, Salil Karipott

Session: (In-Person) Oral Panel—Stimuli and Response, Poster Presentation

Strain, a primary measure of the dynamic mechanical environment, is important with regard to patient aimed orthopedic treatment especially in minimizing complications that arise after certain bone fracture injuries. Currently, methods aimed at assessing the mechanical environment include external stimulating devices that fail to measure strain during normal gait patterns, and estimated parameters computed from different computational models which lack real-time data. With these limitations in determining real time load condition in bone fracture healing, we aimed to fabricate a bone fixation device that provided adequate mechanical stability to a healing bone fracture and measured strain present on the device in a rodent femur. This device transmits measurements wirelessly to a nearby computer for quantification of strain. Our results showed the ability to successfully measure local axial strain during functional loading on a rodent with a femur fracture. This device facilitates the study of mechanical strain and its role in bone healing in preclinical rodent fracture models. Most importantly, this device allows for future rehabilitation protocols that are evidenced-based and patient specific.

Impact of a Single Bout of Blood Flow Restriction Exercise on Muscle Stem Cells

Presenter(s): Jaslena Gill — Human Physiology

Co-Presenter(s): Noah Lovgren

Faculty Mentor(s): Hans Dreyer

Session: (In-Person) Poster Presentation

Blood flow restriction exercise (BFR-Ex) is a form of low-load exercise that restricts extremity blood flow. BFR-Ex has been shown to cause an increase in muscle mass, strength, and muscle stem (satellite) cells. Satellite cells are critical for muscle homeostasis and regeneration. The loss of satellite cells precedes Type II muscle cell decline, a process called sarcopenia, affecting up to 50% of the elderly. The purpose of this study is to determine the effects of a single bout of BFR-Ex on muscle structure 24 hours and 7 days later in young and older adults. We expect satellite cell numbers will increase 24 hours post-exercise and return to normal by 7 days. We also expect signs of muscle cell denervation, cell membrane damage, and recent repair of muscle damage at 7 days post-exercise. Subjects (18-40 yo, 6 female, 6 male) will participate. Subjects will have a baseline biopsy on the left leg followed by a single bout of BFR-Ex on the right leg. Post-BFR-Ex biopsies will be obtained on the right leg after 24 hours and 7 days. Immunohistochemistry will be used to determine cross-sectional area, satellite cell number, fiber type, muscle nuclei, and centrally located nuclei. This will allow us to measure muscle cell denervation, cell membrane damage, and recent repair of muscle damage. To date, one subject has completed the protocol, one has consented, and another will be consented this week. Tissue samples are currently being processed.