Life Sciences Commons^™

Effects Of Wider Step Width On Knee Biomechanics In Obese And Healthy-Weight Participants During Stair Ascent, Derek Scott Yocum

Masters Theses

An increased likelihood of developing obesity-related knee osteoarthritis may be associated with increased peak internal knee abduction moment. Increases in step width may act to reduce this moment. This study focused on how step width influenced the knee joint during stair ascent by healthy and obese participants. Participants ascended stairs while walking at their preferred speed and under one of two step width conditions – preferred and increased. Obese participants experienced greater mediolateral and vertical ground reaction forces (GRFs), as well as increased peak knee extensor moments and push-off peak internal knee adduction moments. The findings of this study indicate …

Extracellular Matrix Remodeling And The Inflammatory Response During Skeletal Muscle Regeneration In Sarcopenic Obese Mice, Lemuel Arthur Brown

Graduate Theses and Dissertations

AIM: Sarocpenic obesity is a national concern within the United States because this metabolic syndrome is tied with reduced mobility and quality of life. Both obesity and aging are associated with insulin-resistance, chronic low-grade inflammation and muscle weakness. Skeletal muscle regeneration is a process that involves the coordinated effort of myogenic regulatory factors (MRFs), inflammatory signaling, and extracellular matrix (ECM) remodeling for optimal regeneration. It has been demonstrated that obesity and aging have a reduction in muscle regeneration. It has not been examined if sarcopenic obesity will further reduce muscle mass and the regenerative process. The purpose of this study …

Panx1 And Panx3 Regulate Adipocyte Development And Fat Accumulation In Vivo, Vanessa R. Lee

Electronic Thesis and Dissertation Repository

The obesity epidemic is a growing concern due to its various comorbidities and associated risk factors. Pannexins 1 and 3 (Panx1 and Panx3), are members of a family of channel-forming glycoproteins that have been reported to be important in paracrine signaling and development. Panx1 and Panx3 are homologous and are regulated in many different cell types, mediating cell proliferation and differentiation. We have shown that Panx1 and Panx3 are expressed in adipocytes and adipose-derived stromal cells (ASCs) throughout the process of differentiation. Mice globally lacking Panx1 (Panx1 KO) have significantly greater total fat mass compared to wildtype (WT) mice under …

Long-Term Supplementation With Leucine Does Not Prevent Development Of Obesity In Rats Fed A High-Fat Diet, Dameon Smith

Graduate Theses and Dissertations

Excess dietary fat consumption has been implicated in the development of obesity and diabetes. Obesity can be characterized by a disproportionate increase in fat mass compared to lean body mass. However, if muscle mass can be increased or maintained in obesity, this may facilitate weight loss by increasing the body’s overall metabolic capacity. Historically, supplementation with the branched-chain amino acid leucine has been shown to increase muscle protein synthesis via the protein kinase mTORC1. Recent studies suggest that supplementation with leucine also has the potential to reduce weight gain and fat deposition in high-fat fed, obese mice. The objective of …

Obesity Over The Life Course: Perspectives In Health And Mortality, Noura E. Insolera

Dissertations, Theses, and Capstone Projects

This dissertation seeks to examine obesity in different contexts throughout the life course. Through empirical analyses, separate stages of the life course are considered: namely childhood through adolescence, young adulthood, and adulthood. By using a life course perspective, it is possible to consider longitudinal and intergenerational approaches to these questions, which will update and inform the current debates surrounding obesity.

Beginning with children, the intergenerational transmission of diet disease knowledge, socioeconomic status, and child health behaviors are considered in their associations with the outcomes of child diet in 2002, and in turn their associations with child obesity in 2007. Information …

Validity And Reliability Of A Photographic Method Of Assessing Body Composition, Elizabeth Z. Macdonald

Theses and Dissertations

The LeanScreenTM app uses photographs and touchscreen technology of an iPad or iPhone to estimate body composition using the Department of Defense (DoD) prediction equations that use cirumference measurements of the neck, abdomen, waist, and hips. The purpose of this study was to determine the validity and reliability of the LeanScreenTM app in 148 weight-stable adults (82 men, 66 women) who were normal weight, overweight, or obese as defined by body mass index. The percent body fat (%BF) of each subject was estimated during one visit using dual-energy x-ray absorptiometery (DXA) as the criterion measure, and three field methods: the …

Physiology And Genetics Of Starvation-Selected Drosophila Melanogaster, Christopher Michael Hardy

UNLV Theses, Dissertations, Professional Papers, and Capstones

In nature, organisms have evolved to survive in stressful environments. This has driven organisms to adopt a wide range of unique adaptations. Investigating the mechanistic basis of these adaptations is an important tool for discovery that has led to major advances in science and medicine.

We study how organisms survive life without food, or starvational stress. Environmental stressors have shaped the quantity and quality of food sources across the globe. This has led to vast differences in the ability of some organisms to tolerate starvation over others. Many researchers have used Drosophila melanogaster as a model to study global patterns …

Anti-Fat Attitudes And Weight Bias Internalization: An Investigation Of How Bmi Impacts Perceptions, Opinions And Attitudes, Laurie Schrider

USF Tampa Graduate Theses and Dissertations

Americans hold negative and judgmental attitudes towards obese and overweight individuals and these anti-fat attitudes and weight stigma have become a damaging form of discrimination. The internalization of weight bias and anti-fat attitudes contributes to negative health outcomes including: feelings of devalue, self-hate, anxiety, depression, body dissatisfaction and eating disturbances. The purpose of this study was to investigate weight bias internalization in individuals who perceive themselves as overweight as well as to examine differences in anti-fat attitudes among normal and overweight individuals. A sample of 202 male and females completed an online survey that assessed anti-fat attitudes via the Anti-Fat …

Inhibition Of B Lymphopoiesis By Adipocytes And Myeloid-Derived Suppressor Cells, Domenick Kennedy

Dissertations

B lymphopoiesis declines with age in humans, mice, and rabbits. Impaired B lymphopoiesis correlates with increased fat in the bone marrow (BM), suggesting that adipocytes negatively regulate this process. In fact, adipocyte factors were found to inhibit B cell development in BM cultures.

Our goal was to understand the mechanism by which adipocytes inhibit B cell development. Through culturing mouse BM cells on OP9 stromal cells in the presence of adipocyte-conditioned medium (ACM), we found that adipocytes promote the accumulation of CD11b+Gr1+ myeloid-derived suppressor cells (MDSCs). These cells were not simply bystanders, as we report for the first time that …

Comparison Of Quick Methods For Determining Body Composition In Female Collegiate Athletes And Obese Females, Mandee E. Martin

Theses and Dissertations--Nutrition and Food Systems

The Body Mass Index (BMI) is a tool used broadly by public health agencies to assess weight in populations. However, when differentiating between fat mass and fat free mass the formula (BMI = weight in kilograms/height in meters2) is not applicable. Research suggests that evaluating body fat percentage and adipose tissue deposition may provide a nuanced indication of overall health, making it more accurate on an individual basis. This study evaluated four methods (Body Mass Index, waist circumference, A Body Shape Index, and Waist to Stature Index) that assess body composition and their ability to predict body fat percentage in …

Promoting Healthy Eating And Physical Activity: A Qualitative Examination Of Community-Based Obesity Interventions In Rural Kentucky, Brooke F. Butterworth

Theses and Dissertations--Nutrition and Food Systems

Rural Americans are medically underserved groups and are at greater risk of becoming obese than urban Americans. The purpose of this qualitative study was to determine the perceived causes of obesity in six counties of rural Kentucky and to determine how to customize strategies to reduce obesity in these areas. University of Kentucky Cooperative Extension Service Agents formed coalitions in each of the six counties to assess their communities’ needs and assets to inform plans for implementing evidence-based obesity interventions. Between February and August of 2015, the coalitions were convened for a total of 11 meetings. Each of the coalition …

Uncovering New Roles For The Aryl Hydrocarbon Receptor (Ahr) In Breast Cancer, Justin Kirk Tomblin

Theses, Dissertations and Capstones

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that is responsive to many exogenous and endogenous ligands. AHR is of particular interest in cancer, and has been shown to play roles in tumor progression. As such, it has received growing attention as a possible chemotherapeutic target. Obesity increases the risk of breast cancer, complicates treatment of breast cancer, and stimulates the growth of larger, more aggressive mammary tumors. Many breast tumors in obese women are estrogen receptor (ER)-positive and, while targeting hormone receptors like ER is beneficial, many obese women see a recurrence of their cancer after standard …

Influence Of Overweight, Obesity, Social Support, And Self-Efficacy On Breastfeeding Outcomes Among African-American Women, Elizabeth Hoo

Walden Dissertations and Doctoral Studies

Breastfeeding reduces morbidity and mortality among mothers and children, yet African-American women breastfeed at lower rates than women of other racial and ethnic groups do. Higher rates of overweight, obesity, and low socioeconomic status may be contributing factors in this population; however, limited research exists regarding the roles of maternal overweight and obesity on breastfeeding outcomes. The purpose of this study was to examine whether social support and self-efficacy positively influence breastfeeding outcomes among overweight and obese African American women. Self-efficacy and social support theories provided the theoretical framework for the study. Research questions examined whether (a) maternal overweight and …

Sprague Dawley Rats Were Able To Ferment Purified Resistant Starch And Whole Grain Starch On Moderate And High Fat Diets, Justin Lamont Guice

LSU Master's Theses

Whole grain (WG) and fat content of the diet have been previously shown to affect intestinal fermentation and phenotype conferred by high–amylose maize starch (HAM), a form of fermentable dietary fiber. The current study was designed to compare rodent gut health following consumption of whole grain and non–whole grain prebiotics on moderate fat (MF) and high fat (HF) diets using a 2x2x2 factorial design. MF and HF diets were prepared to contain the following diet sources: (1) control starch with no WG or RS [CON], (2) whole grain waxy corn flour with low RS [WWG], (3) purified HAM resistant starch …

Central And Peripheral Weight Gain Affect Trunk Kinematics And Lower-Extremity Muscle Activation Differently During Sit-To-Stand, Michelle Christine Walaszek

Theses and Dissertations--Kinesiology and Health Promotion

Background: Obesity-induced alterations in biomechanics and muscle recruitment during activities of daily living, such as sit-to-stand (STS) are often attributed to increases in adipose tissue (AT) mass. Central or peripheral distribution of AT may differently affect biomechanics and muscle recruitment.

Methods: Fifteen healthy, normal weight (BMI 22.4 ± 1.9 kg/m², 24.1 ± 4.2 years) subjects volunteered. External loads equivalent to a 5 kg/m² BMI increase were applied in three conditions: unloaded (UN), centrally loaded (CL), and peripherally loaded (PL). Subjects completed three successful STS movements in a backless chair under each load condition in random order. Motion …

Autophagy Regulation After Diet And Exercise In Non-Alcoholic Fatty Liver Disease, Megan Elizabeth Rosa

Graduate Theses and Dissertations

Along with the rise in obesity, rates of non-alcoholic fatty liver disease (NAFLD) have also increased. NAFLD may begin with fat accumulation in the liver, but can progress to non-alcoholic steatohepatitis (NASH), fibrosis, and eventual cirrhosis. With no pharmacological treatment for NASH, lifestyle interventions appear vital to maintaining liver health. Previous work has shown aberrant mitochondrial content/quality and autophagy in models of NAFLD. Exercise is known to improve mitochondrial health and possibly autophagy, thus autophagy may be a key regulatory factor for treatment of obesity induced-NAFLD. PURPOSE: The purpose of the study was to examine how weight loss from diet …