Master of Science, The Ohio State University, 2021, Dentistry

Abstract: Osteoporosis is a systematic skeletal disease that reduces bone mineral density (BMD) leading to a high risk of bone fracture with aging. While dual energy x-ray absorptiometry (DEXA) has been widely used to diagnose the osteoporosis, its 2D image limits its reliability to measure BMD. Otherwise, conventional medical computed tomography (CT) provides more comprehensive 3D images to improve the BMD based diagnosis. However, its high radiation dose limits access of patients. The objective of this study was to examine whether 3D dental cone beam CT (CBCT) can assess age-dependent changes of volumetric BMD and morphology with less radiation dose than the medical CT. Methods: After IRB approval, total of 138 clinical CBCT images were retrospectively obtained from 73 female and 65 male patients (20 to 69 years of age). The 3D images of cervical vertebral bodies (C2 and C3) were digitally isolated by removing lateral and posterior processes at 10 voxels from either side of the vertebral end plate. Non-bone voxels outside of the C2 and C3 were removed using a segmentation algorithm. A gray level, which is proportional to BMD, was obtained for each bone voxel and averaged to compute the mean gray value. Morphology including volume, heights, widths and concavities was also measured. Two-way ANOVA was performed with p<0.05.   Results: The C2 and C3 BMD of women over age 60 were significantly lower than those younger age 50 (p<0.010), while they were not significantly different between the age groups of men (p>0.061). The morphology of C2 and C3 were not significantly different between age groups of women (p>0.084). Conclusion: The reduced BMD of older women likely results from postmenopausal demineralization of bone. The current findings suggest that CBCT can detect age-dependent changes of cervical BMD providing baseline information to develop an alternative tool to diagnose osteoporosis.

Committee: Do-Gyoon Kim (Advisor); Toru Deguchi (Committee Member); Damian Lee (Committee Member); Fengyuan Zheng (Committee Member) Subjects: Dentistry; Medical Imaging

Master of Science, The Ohio State University, 2016, Human Ecology: Human Nutrition

Background: The two leading causes of death of women in the United States, cardiovascular disease and cancer, are associated with elevated chronic inflammatory markers. There is a critical need to develop therapies which are safe and efficacious in order to lower chronic inflammation and improve health outcomes in women, specifically obese postmenopausal women, a group particularly vulnerable to chronic inflammation. Methods: This pilot study was a single-arm experimental pre-post test design, that tested the efficacy of the LAS-03 (low added sugar, high fiber, and omega-3 fatty acids) intervention to improve overall diet quality and lower inflammation in obese postmenopausal women. LAS-03 was delivered by a registered dietitian via in-person and phone-based counseling over 12 weeks. Self-reported dietary intake over the previous 3 months was assessed using electronic Food Frequency Questionnaires. Primary outcome measures included self-reported dietary intake of dietary components emphasized in the intervention, diet quality as measured by the HEI 2010, and biomarkers of inflammation as measured by serum inflammatory cytokines (tumor necrosis factor a receptor-2 (TNFaR-II), interleukin-6 (IL-6), high sensitivity C-reactive protein (hsCRP)). Urinary excretion of sucrose, a biomarker of dietary intake of added sugars, was measured for validation purposes. Results: Self-reported dietary intake improved for added sugar, sucrose, sweet servings, fatty fish, and omega-3 fatty acids DHA and EPA (all p<0.05). There was also a significant increase in calculated total HEI 2010 scores as well as HEI 2010 subgroup scores: vegetables, greens and beans, seafoods and plant proteins, fatty acids, empty calories (p<0.05). Mean inflammatory markers all trended downwards and TNFaR-II significantly decreased pre-post intervention (p<0.05). There were significant correlations between fasting spot urinary sucrose excretion (g/L creatinine) and self-reported 24-hour dietary intake (open full item for complete abstract)

Committee: Tonya Orchard (Advisor); Rebecca Andridge (Committee Member); Julie Kennel (Committee Member); Carolyn Gunther (Committee Member) Subjects: Biology; Health; Health Sciences; Nutrition

Doctor of Philosophy, The Ohio State University, 2015, Nutrition Program, The Ohio State University

Menopausal loss of ovarian function associates with changes in body composition, increasing the risk of developing central obesity, metabolic syndrome, and other chronic diseases. Breast cancer is the second leading cause of cancer deaths in women, with the majority occurring in postmenopausal women. Obesity is associated with increased risk of postmenopausal breast cancer and the underlying mechanism(s) likely involves obesity-related metabolic dysregulation. Therefore, improvement of metabolic status may be a useful approach to decrease the risk of breast cancer. Naringenin is a flavonone found in citrus fruits and tomatoes. It possesses anti-tumor properties as well as ameliorates obesity-associated metabolic dysregulation. Therefore, we hypothesized that naringenin ameliorates metabolic disturbances not only resulting from loss of ovarian function but also that associated with postmenopausal obesity. Furthermore, we hypothesized that naringenin inhibits mammary tumor growth induced by postmenopausal obesity. To determine the effect of naringenin on metabolic changes resulting from loss of ovarian function, ovariectomized C57BL/6J female mice were fed a control diet (10% kcal fat) for 11 weeks. Half of the mice were supplemented with 3% naringenin for the next 11 weeks. Ovariectomized mice exhibited hyperglycemia and increased adiposity. Naringenin supplementation decreased plasma leptin and leptin mRNA in adipose depots as well as adipose tissue inflammation. Naringenin-supplemented mice also had reduced hepatic lipid accumulation with corresponding alterations of hepatic gene expression associated with de novo lipogenesis and gluconeogenesis. Thus, dietary naringenin attenuated many of the metabolic disturbances associated with ovariectomy in female mice. Then, the effect of naringenin on metabolic disturbances in a mouse model of postmenopausal obesity was examined. Ovariectomized mice were fed a high-fat diet (60% kcal fat) for 11 weeks to induce obesit (open full item for complete abstract)

Committee: Martha Belury (Advisor); Earl Harrison (Committee Member); Kichoon Lee (Committee Member); Lisa Yee (Committee Member) Subjects: Nutrition