Auburn Research Day 2022

Kyra S. Lowery 1 ; Joshua S. Godwin 2 ; Abigail M. Bogard 1 ; Tyler M. Martinez 1 ; Michael D. Goodlett 1,3 ; Joseph L. Edison 1,3 ; Michael D. Roberts 1,2 ; Kaelin C. Young 1,2 1 Edward Via College of Osteopathic Medicine-Auburn Campus; 2 School of Kinesiology, Auburn University; 3 Athletics Department, Auburn University B i omed i ca l Resea rch | Med i ca l St udent Ultrasound Echo-Intensity Does Not Correlate With Peripheral Quantitative Computed Tomography Markers Of Skeletal Muscle Quality 15

Purpose: Ultrasound imaging of skeletal muscle has become a common non-invasive method for measuring changes in skeletal muscle size and composition. Echo-intensity from ultrasound imaging has become a popular marker for muscle quality, as a lower echo-intensity is believed to represent a higher amount of functional muscle tissue, while a higher echo-intensity represents greater amounts of adipose and connective tissue. The purpose of this study was to determine if ultrasound derived echo-intensity is a marker of changing muscle quality following resistance training by comparing echo-intensity to pQCT derived muscle density and intramuscular adipose tissue. Methods: 34 untrained college females (age; 21 ± 2.1, BMI; 23.37 ± 3.36) participated in 10 weeks of resistance training. Prior to the first training bout, and 72 hours following the last bout, all participants completed a series of scans in both pQCT and ultrasound. Ultrasonography images were obtained of the vastus lateralis of right leg in the sagittal plane with a b-mode imaging device (LOGIQ S7 Expert, GE Healthcare, USA). Settings were kept consistent across all participants (Depth: 5.0 cm, Frequency: 12MHz, Gain: 55 dB, Dynamic Range: 72) and the same technician performed all scans. Peripheral quantitative computed tomography (pQCT) was used to measure muscle density and intramuscular adipose tissue (IMAT). Cross-sectional images of the right thigh were obtained using a pQCT scanner (Stratec XCT 3000, Stratec Medical, Pforzheim, Germany) with single 2.4 mm slice thickness, voxel size of 0.4 mm

and scanning speed of 20 mm/sec. All scans were performed and analyzed by the same investigator. Test-retest reliability for ultrasound (ICC 3,1 = 0.996; SEM = 4.14; MD = 11.47 AU) and pQCT (ICC 3,1 = 0.99; SEM = 0.84 cm 2 ; MD = 2.32 cm 2 ) was previously determined. All images were analyzed using ImageJ software (version 1.51, National Institutes of Health). Statistics were performed in SPSS v26.0 (IBM Corp, Armonk, NY, USA). Paired samples t-tests were performed on all variables to compare pre to post changes and Pearson R correlation coefficients were used for determining correlations between echo- intensity and pQCT variables. All data are presented as mean ± standard deviation and significance level set at p < 0.05. Results: Following 10 weeks of resistance training, muscle density did not significantly change (-1.25 ± 0.68 mg/cm3, p = 0.077), IMAT significantly increased (+0.193 ± 0.056 cm2, p = 0.0018), and echo-intensity significantly decreased (-9.88 18.33 AU, p = 0.003). Using Pearson R correlation, echo-intensity did not correlate to muscle density or IMAT using change scores (r = -0.055, p = 0.750 and r = 0.149, p = 0.397; respectively) and percent change scores (r = -0.022, p = 0.901 and r = 0.192, p = 0.276; respectively). Conclusion: Given the findings in the current study, ultrasound derived echo- intensity should not be used as a measurement of muscle quality following resistance exercise training. Further investigation into ultrasound echo-intensity is needed to understand what echo- intensity represents physiologically with respect to muscle composition and quality.

B i omed i ca l Resea rch | Med i ca l St udent Covid-19 and Vitamin D: Is There A Direct Relationship Between Vitamin D Deficiency And Covid-19 Severity?

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Andrew J. Gonedes, OMSIII; and Gary Mount, PharmD VCOM-Auburn

COVID-19 Coronavirus disease is an ailment ravaging the world with multiple variant strains. The World Health Organization (WHO) renamed the 2019 nCoV to COVID-19, a disease characterized by pneumonia symptoms. It is thought the disease originated in Wuhan City in China (Shakoor et al., 2021). The airborne virus rapidly spread from its origin to other parts of the globe in record time due to the increased movement of people through road, rail, and air transport. According to Kumar et al. (2021), COVID-19 is characterized by lower respiratory tract viral infection with symptoms including oxidative stress that make it harder for patients to absorb an adequate amount of oxygen into the bloodstream (Slominski et al., 2021). Figure 1 is a diagrammatic representation of the COVID- 19 virus structure. The spike glycoprotein attaches to healthy cells, enter, multiply, and burst open to release the newly-created viruses. Slominski et al. (2021) define COVID-19 as a severe respiratory syndrome containing a positive RNA strain belonging to the Coroniridae family. The virus has a moderately low mortality rate, albeit several times more lethal than conventional influenza viral infections (Slominski et al., 2021).

Mansur et al. (2020) add that the COVID-19 virus "binds to ACE2 enzyme, making more angiotensin II available to cause damage" (p. 268). Thus, increased production of angiotensin II in the body fosters an attack on the respiratory system and makes the ailment more potent among infected patients. Vitamin D is one of the most valuable nutrients in the body and can be found on many food items and the sun's ultraviolet rays. Iddir et al. (2020) clarify that Vitamin D is present in eggs, mushrooms, fish, and fortified milk diets. However, the higher amount of functional Vitamin D comes from the sun's rays. In particular, the ultraviolet-B (UVB) is absorbed through the human skin and is responsible for reducing cytokine storms (Grant et al., 2020). Slominski et al. (2021) describe Vitamin D as a fat-soluble prohormone that plays an essential role in physiological functions in the body, such as the regulation of adaptive and innate immunity in the body. Therefore, Vitamin D is vital to fighting pathogens in the body. From this information, this study will investigate whether there is a credible relationship between Vitamin D in the body and the severity of COVID-19 among patients.

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