Medicine and Health Sciences Commons^™

The Effects Of Resistance Training On Cognition And Brain Health In Older Adults At Risk For Diabetes: A Pilot Feasibility Study, Joyla Furlano

Electronic Thesis and Dissertation Repository

Type 2 diabetes is associated with neurocognitive deficits and increased risk for dementia, with high prevalence of diabetes occurring in old age. There are many known risk factors for diabetes, including physical inactivity, obesity, and prediabetes. Studies show that individuals who are at risk for diabetes (i.e., have one or more risk factors) already experience some brain deficits seen in diabetes. One way to combat these deficits is aerobic exercise; however, the effects of resistance exercise in this population are relatively unknown. The objectives of this thesis were to report on the current evidence of brain deficits in prediabetes, and …

The Effect Of Obesity On Revision Total Knee Arthroplasty: Functional Outcome, Ninety-Day Costs, Reoperations, Readmissions And Cost-Effectiveness, Mohamad Nasser Eddine

Electronic Thesis and Dissertation Repository

The demand for revision total knee arthroplasty (RTKA) is increasing due to obesity and an aging population. The purpose of this study is to evaluate the effect of different body mass index (BMI) categories on RTKA using a retrospective cohort analysis. The first part was to assess patients’ functionality post-RTKA. The second part was to determine the survival of RTKA and re-revision rate. The third part was to explore the complication and readmission rates, and to estimate the 90-day costs of RTKA. We found the most common indication for RTKA in super obese patients is infection, unlike other BMI categories, …

Free Fatty Acid Treatment Alters Autophagy During Mouse Preimplantation Embryo Development, Zuleika C. L. Leung

Electronic Thesis and Dissertation Repository

Obesity-induced hyperlipidemia is one of the main factors for female infertility. Hyperlipidemia, specifically with high levels of palmitic acid (PA) and oleic acid (OA), interferes with preimplantation development. Autophagy is essential in early embryo development but, it is unknown whether hyperlipidemia affects autophagic mechanisms in preimplantation embryos. It was hypothesized that PA will alter autophagy in preimplantation mouse embryos and that the subsequent effects will be reversed by OA. PA impaired blastocyst development by arresting embryos at the 8-cell stage. PA also elevated early embryo autophagy by increasing autophagosome formation, decreasing maturation, and disrupting degradation. Co-treatment with OA showed developmental …

Effects Of Ergothioneine On Endothelial Cell And Macrophage Characteristics, And Markers Of Atherosclerosis Risk Under High Lipid Conditions, Daniel Lam-Sidun

Electronic Thesis and Dissertation Repository

Ergothioneine (EGT) is an antioxidant and potential anti-inflammatory molecule that may have protective effects against the lipid-induced oxidative stress and inflammation that occurs in the vasculature of individuals with obesity and metabolic syndrome. This thesis addresses the hypothesis that EGT supplementation decreases endothelial cell dysfunction and macrophage inflammatory characteristics under high lipid conditions, and markers of atherosclerotic risk in diet-induced obese mice. Results showed that EGT did not influence endothelial tube formation or stability but reduced nitric oxide production in endothelial cells. Moreover, EGT decreased the production of reactive oxygen species, and potentially nitric oxide, by macrophages. In diet-induced obese …

Investigating Pathways Associated With Intervertebral Disc Degeneration And Back Pain., Geoffrey J. Kerr

Electronic Thesis and Dissertation Repository

Lower back pain (LBP) is one of the most common conditions worldwide, yet, current therapeutics are limited to symptomatic relief and do not directly treat the underlying cause of pain. This is largely due to an incomplete understanding of the biological pathways and tissues involved in LBP. While many tissues appear to be involved, intervertebral disc (IVD) degeneration is believed to be a major contributor.

The main aim of this thesis was to characterize the role of two environmental risk factors, mechanical loading and obesity, in the initiation of IVD degeneration and associated pain using the mouse as a preclinical …

The Now Trial: A Pragmatic Randomized Controlled Trial Of Personalized, Genetic-Based Lifestyle Advice, Justine Rochelle Horne

Electronic Thesis and Dissertation Repository

Background: The impact of nutrigenomics and lifestyle genomics interventions on health outcomes and behaviours remains controversial and under-explored.

Objectives: To determine the short-term (3-month), moderate-term (6-month) and long-term (12-month) impact of providing personalized, genetic-based lifestyle information and advice on anthropometric measures, as well as dietary intake and adherence.

Methods: The nutrigenomics, overweight/obesity and weight management trial (NOW Trial) is a pragmatic randomized controlled trial that was incorporated into the Group Lifestyle Balance™ (GLB) program (N=140). Inclusion criteria: overweight or obesity (BMI ≥ 25 kg/m²), ≥ 18 years of age, English-speaking, having access to internet at least …

A Coaching And/Or Education Intervention Targeting Physical Activity And Nutrition Behaviours In Parents With Overweight/Obesity And Their Children, Shazya Karmali

Electronic Thesis and Dissertation Repository

The purpose of this dissertation is to provide a detailed overview of, findings from, and experiences participating in a 3-month randomized controlled trial (RCT) targeting obesity-related behaviours in parents with overweight/obesity (body mass index [BMI] ≥ 25 kg/m²) and their children (2.5-10 years old, any weight; N = 50 dyads). A concurrent mixed methods study comprised of an RCT and descriptive qualitative design was utilized. Parent-participants received Co-Active Life Coaching (CALC) and webinar-based health education (intervention) or education only (control). To address the dissertation’s purpose, Chapter II provides a detailed methodological account of the program, including rationale and …

Examining The Relationship Between Body Mass Index And Health-Related Quality Of Life Perception Among People With Mental Illness, Fatima Bukair

Electronic Thesis and Dissertation Repository

People suffering from mental illness are three times more likely to die prematurely from ‘natural’ causes than those without mental disorders as a result of their physical condition. Their life expectancy is reduced by 12-19 years. Obesity is commonly associated with mental illness and accounts for increased risk of cardiovascular disease, diabetes mellitus, stroke, heart disease, some cancers and osteoarthritis. This paper examined the relationship between body mass index (BMI) and health-related quality of life perception using the Short-Form Health Survey 36 among people living with mental illness. A Multivariate Multiple Regression model was employed to estimate the variables that …

Attenuation Of Obesity, Hepatic Steatosis And Reversal Of Atherosclerosis By The Flavonoids Naringenin And Nobiletin, Amy C. Burke

Electronic Thesis and Dissertation Repository

Naringenin and nobiletin are naturally-derived citrus flavonoids that have significant lipid-lowering and insulin sensitizing effects in vitro and in vivo. In murine models of obesity, metabolic dysfunction and atherogenesis, these flavonoids protect against the development of cardiometabolic disease. However, the ability of naringenin and nobiletin to reverse existing metabolic dysfunction and atherosclerosis has not been investigated.

The purpose of this thesis was to investigate the ability of the citrus flavonoids, naringenin and nobiletin, to reverse obesity, metabolic syndrome and atherosclerosis in two different mouse models of atherosclerosis regression. The first chapter demonstrates in Ldlr^-/- mice with diet-induced obesity, …

Bariatric Surgery Recipients' Needs For Long-Term Health And Well-Being; Perspectives Of Patients And Providers, Rebecca H. Liu

Electronic Thesis and Dissertation Repository

The overall purpose of this dissertation was to examine what is needed in bariatric surgery programming to support long-term health and well-being from the perspectives of the patient and providers. Study 1 assessed what bariatric surgery recipients perceive they need to best support their long-term health and well-being from a provincial sample (Ontario, Canada), and from an international sample. Study 2 explored the physical, psychological, social, and clinic-related experiences of individuals who underwent bariatric surgery at least two years prior. Study 3 investigated what bariatric clinic staff believe surgery recipients need to best support their long-term health and well-being.

Findings …

Cost Effectiveness Of Primary Total Hip Arthroplasty For Varying Levels Of Bmi, Karthikeyan E. Ponnusamy

Electronic Thesis and Dissertation Repository

The demand for hip arthroplasty is increasing rapidly due to a combination of an aging population as well as an increasing level of obesity in the country. The purpose of this study is to evaluate the risks and benefits of arthroplasty for patients of different obesity classes. The first two parts were to use a systematic review with meta-analysis and retrospective chart review to quantify the risks and benefits in different obesity classes. The third part was to perform a cost-effectiveness analysis to weight the balance between the two. We found that higher obesity classes are at higher risk of …

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 …

A Link Between Paediatric Asthma And Obesity: Are They Caused By The Same Environmental Conditions?, Phylicia Gonsalves

Electronic Thesis and Dissertation Repository

The highly associated paediatric conditions of asthma and overweight have seen dramatic increases over the past few decades. This thesis explored air pollution exposure as a potential underlying mechanism of co-morbid asthma and overweight among adolescents aged 12 to 18 years. Data from the Canadian Community Health Survey were merged with a database containing estimates of air pollution as assessed by particulate matter ≤ 2.5 microns (PM_2.5) concentrations at the postal code centroid in southwestern Ontario. Logistic regression was used to conduct the analysis. Adolescents were more likely to be overweight as PM_2.5 concentrations increased. There was …

Bringing An Evidence-Based Nutrition And Exercise Lifestyle Intervention Program (Nelip) For Obese Pregnant Women Into Clinical Practice, Samantha Langstaff

Electronic Thesis and Dissertation Repository

One purpose was to identify the need for specialized care (My Clinic) for women with a pre-pregnancy body mass index (BMI) of ≥ 35 kg/m^2.. Women receiving My Clinic care were compared to a matched cohort control group (perinatal database, N=47). My Clinic care significantly reduced rates of macrosomia (5% vs 28%, p=0.02) and small birth weight babies (0% vs 6%, p=0.00) compared to perinatal database.

The second purpose was to test the efficacy of a Nutrition and Exercise Lifestyle Intervention Program (NELIP) in this clinical setting to prevent excessive weight gain, macrosmia, small birth weight …

Inhibition Of Elongation Factor 1a-1 Activity And Hepatic Lipotoxicity, Alexandra Margaret Anne Hetherington

Electronic Thesis and Dissertation Repository

Elongation factor 1A-1 (eEF1A-1) was previously identified as a mediator of fatty acid-induced cell death (lipotoxicity) downstream of endoplasmic reticulum (ER) stress. Furthermore, inhibition of the peptide elongation activity of eEF1A-1 with the cyclic depsipeptide didemnin B (DB) diminishes ER stress and lipotoxicity in cultured hepatocytes. Since ER stress is involved in nonalcoholic fatty liver disease (NAFLD), it was hypothesized that administration of DB to obese mice with NAFLD would reduce hepatic lipotoxicity. Treatment with DB for one week improved several parameters associated with hepatic lipotoxicity and modestly decreased food intake without evidence of illness. Liver triglycerides and protein markers …

Modulation Of The Cardiomyocyte Hypertrophic Responses To Endothelin-1 By Adipocytes, Suresh Chandra Bairwa

Electronic Thesis and Dissertation Repository

Leptin and adiponectin are the adipokines that are shown to exert pro-hypertrophic and anti-hypertrophic effects respectively, in cardiomyocytes. We sought to determine the direct interaction between the adipocytes and cardiomyocytes during endothelin-1 (ET-1)-induced cardiomyocyte hypertrophy and determine the role of leptin and adiponectin.

The adipose tissue conditioned medium (ACM) inhibited the ET-1-induced hypertrophy in a concentration-dependent manner and this anti-hypertrophic effect was more potent or reversed in the presence of leptin receptor antagonist (LRA; 0.1 nM) or adiponectin receptor-1 antibody (ARA; 100 ng/mL), respectively. ACM from heart failure rats induced by coronary artery ligation or obese rats did not mitigate …

Body Mass Index Trajectories: The Effect Of Fetal Size And Early Life Modifiable Factors, Mathew Roy

Electronic Thesis and Dissertation Repository

Background: This study examined the relationship between small for gestational age (SGA) status at birth, a measure of fetal growth restriction, and childhood body mass index trajectories (BMI) using data from the National Longitudinal Survey of Children and Youth. Analytic Method: Using latent growth curve modeling, the growth trajectories of a cohort of small and appropriate for gestational age singletons were modeled from 2-10 years (N=1,273 at baseline). Results: SGA status had no effect on the growth trajectories of children after adjusting for prenatal and early life sociodemographic and maternal variables, and also early life modifiable factors. Moreover, the modifiable …

Maternal Employment During Infancy And Toddlerhood: Mechanisms For Associations With Childhood Overweight/Obesity In Canada, Nathalie Victoria Metzer

Electronic Thesis and Dissertation Repository

Background: Childhood overweight and obesity is a major public health issue, with approximately 1 in 3 children classified as overweight or obese in Canada. Research suggests that maternal employment during childhood may be associated with later overweight and obesity risk, but it is not known whether employment during infancy and toddlerhood has a similar effect on weight status. Mechanisms such as reduced breastfeeding and use of informal child care have been proposed in the literature but not been formally tested among infants and toddlers. It is important to identify possible mechanisms that could explain the association with overweight and obesity …

Fully Automated Segmentation And Quantification Of Abdominal Adipose Tissue Compartments In Mouse Mri, Colin M. Mccurdy

Electronic Thesis and Dissertation Repository

Obesity currently affects 25% of Canadians and is strongly associated with many diseases including diabetes, cardiovascular disease, and cancer. However, only Intra-Abdominal Adipose Tissue (IAAT) is an important predictor of obesity associated disease and mortality. Magnetic Resonance Imaging (MRI) is an effective modality for imaging fat and methods have been developed to automate segmentation of IAAT. Currently existing techniques for automated segmentation in mice require acquisition using high magnetic field MRI equipment and use image acquisition techniques with low precision for fat quantification. We demonstrate a new fully automated technique for fat quantification in clinical strength mouse MRI through adaptation …

Man Versus Food: An Analysis Of 'Dude Food' Television And Public Health, Amy R. Eisner-Levine

Electronic Thesis and Dissertation Repository

Contemporary food television has moved away from an instructional and cooking-centered model, to an entertainment and eating-focused one. However, public health researchers have not considered these shows in the wake of rising obesity rates. This thesis is concerned with the kinds of messages food television conveys about food and eating and is guided by three research questions: How are food and eating represented on the shows? How is health addressed? How do these shows work to create and promote a more acceptable popular discourse around unhealthy eating habits? Through an analysis of Diners, Drive-Ins and Dives, You Gotta Eat …

The Impact Of Obesity On Employment Participation And Earnings Among Working-Age Women In Canada: Evidence From The Nphs Longitudinal Data, Samantha L. Larose

Electronic Thesis and Dissertation Repository

Background: The direct medical care costs attributable to obesity are well-known, but little is known about the indirect costs of obesity. In particular, less is known about the impact of obesity on employment participation and earnings, especially among women in Canada.

Objectives: The objectives of this study are to examine the association between obesity and employment participation and earnings, if employed, among Canadian women.

Methods: Data were taken from the last six cycles of the National Population Health Survey from 2000/01-2010/11 longitudinal cohort data from women aged 18-53 years. The association between obesity and labour market participation was analyzed using …

Effects Of Niacin In Human Vascular Endothelial Cells During Lipotoxicity, Jennifer M. Hughes-Large

Electronic Thesis and Dissertation Repository

Nicotinic acid (NA) can improve vascular function and regeneration independent of correcting dyslipidemia. NA, as a potential biosynthetic precursor for NAD⁺, may elicit these vascular benefits through SIRT-mediated NAD⁺-dependent responses. We hypothesized that NA improves endothelial cell function under lipotoxic conditions through NAD⁺-dependent pathways. Angiogenic function in excess palmitate was assessed by tube formation assay following treatment of human microvascular endothelial cells (HMVEC) with NA or nicotinamide mononucleotide (NMN; a direct NAD⁺ precursor). Both NA and NMN improved HMVEC angiogenic function during palmitate overload. Only NMN increased cellular NAD⁺ and SIRT1 activity, …

Fetal And Neonatal Exposure To Nicotine Augments Hepatic Fatty Acid Synthesis In Rat Offspring Long-Term, Noelle L. Ma

Electronic Thesis and Dissertation Repository

While nicotine replacement therapy (NRT) is presumed to be a safer alternative to smoking in pregnancy, the long-term consequences in offspring are still largely unknown. Animal studies now suggest that maternal nicotine exposure during pregnancy and lactation (MNE-PL) leads to a wide variety of adverse outcomes for the offspring, including increased adiposity. The focus of this study was to investigate how MNE-PL in rats may lead to liver dysfunction long-term in offspring through alterations in gene expression and epigenetic modifications. Postnatal day 180 (PND180) offspring exposed to nicotine during pregnancy and lactation (1mg/kg/day) exhibited increased circulating and hepatic triglycerides concomitant …

Elongation Factor 1a-1 And Hepatocyte Response To Fatty Acid Excess, Alexandra M. Stoianov

Electronic Thesis and Dissertation Repository

Obesity is associated with elevated levels of serum fatty acids, which accumulate in nonadipose tissues including the liver. Elongation factor 1A-1 (EF1A-1) has previously been shown to participate in the cell stress and death response of cardiomyocytes to excess saturated fatty exposure, and in steatotic mouse myocardium. In this thesis, the hypothesis that the hepatocyte response to fatty acid overload involves EF1A-1 was tested. EF1A-1 expression was induced in the livers of obese mice in association with severe hepatic steatosis, and in HepG2 human hepatoma cells in response to excess palmitate. Partial translocation of EF1A-1 from the ER to polymerized …

Obesity And Health Care Utilization Trends In Canada During The Period 1996-7 To 2009-10, Michael Lebenbaum

Electronic Thesis and Dissertation Repository

In Canada, there have been large improvements in the management of chronic diseases attributed to obesity such as diabetes, hypertension and high cholesterol since the 1990s. How this trend has impacted the health care utilization patterns of obese individuals relative to normal weight individuals is unknown in Canada. This study examined health care utilization across categories of body mass index in Canada during the time period 1996 to 2010 using the 1996-7 National Population Health Survey and the 2000-1 and 2009-10 Canadian Community Health Surveys. I found that there were significant declines in the intensity of utilization of general practitioner/family …

Weight Status Underestimation Among Canadian Adolescents: An Important And Frequently Overlooked Aspect Of The Childhood Obesity Epidemic, Mary Ellen Kuenzig

Electronic Thesis and Dissertation Repository

Objectives: Overweight adolescents frequently fail to recognize that they are overweight. This project examines the magnitude of weight status underestimation among overweight adolescents and identifies predictors of this underestimation.

Methods: Data from the Canadian Community Health Survey (2001-2010) were used. Overweight adolescents (N=11,452) reporting they were underweight or about right were classified as underestimating their weight. The time trend in underestimation and effects of individual-level characteristics on underestimation were examined using logistic regression. Multilevel analysis examined the effect of weight status of community-based reference groups.

Results: For every 5 overweight male adolescents, 3 underestimated their weight; 2 of 5 overweight …

The Change Program: Comparing An Interactive Versus Prescriptive Telephone-Based Behavioural Intervention On The Psychological And Physiological Profiles Of University Students With Obesity, Erin S. Pearson

Electronic Thesis and Dissertation Repository

The purpose of the CHANGE (Coaching towards Healthy Actions Naturally through Goal-related Empowerment) Program was to compare the effectiveness of an interactive versus prescriptive 12-week telephone-based behavioural intervention on the psychological and physiological profiles of university students with obesity. Motivational Interviewing administered using Co-Active Life Coaching (MI-via-CALC) and a structured lifestyle treatment following the LEARN (Lifestyle, Exercise, Attitudes, Relationships, Nutrition) Program for Weight Management were examined.

Article 1 provided a methodological account of the CHANGE Program which included a detailed rationale for its development and a comprehensive description of the methods used. Because goal setting has been established as an …

Association Between The Fast-Food Environment And Obesity In Canada: A Cross-Sectional Analysis, Simon Hollands

Electronic Thesis and Dissertation Repository

Frequent fast-food consumption is associated with weight gain therefore it is hypothesized that relative availability of fast-food is a risk factor for obesity. This thesis examined the association between the neighbourhood-level density of fast-food outlets and adult body mass index (BMI) in Canada. Population-based data on BMI and socio-economic variables from the 2008 Canadian Community Health Survey [CCHS] and selected neighbourhood-level socio-economic data from 2006 Canadian Census were merged with a commercial database containing geographic locations of all restaurants in Canada. The association between BMI and fast-food density (per 10,000 people in CCHS respondent’s FSA) was analyzed using ordinary least …

The Relationship Between Diet Quality And Obesity In Canadian Adults: Evidence From The 2004 Canadian Community Health Survey, Kalaivaani Sundararajan

Electronic Thesis and Dissertation Repository

Background: The relationship between diet quality and obesity is unknown in Canadian adults.

Objectives: The objective of this study is to examine the association of diet quality with obesity in Canadian adults.

Methods: Data were taken from the 2004 Canadian Community Health Survey. Three indices were constructed using diet recall data: Diet Quality Index (DQI), Healthy Eating Index (HEI) and Glycemic Index (GI). Obesity was measured with body-mass index. Various confounders were also controlled. Latent-class and ordered probit modeling were used to investigate the association between diet quality and obesity.

Results: Latent-class analysis suggested that the …

Motivational Coaching: Its Efficacy As An Obesity Intervention And A Profile Of Professional Coaches, Courtney E. Newnham-Kanas

Electronic Thesis and Dissertation Repository

Abstract

The primary purpose of this dissertation was to examine Motivational Interviewing (MI) using Co-Active life coaching (CALC) skills as an intervention for individuals struggling with obesity. The secondary purpose was to investigate the characteristics of the interventionists, the Certified Professional Co-Active Coaches (CPCCs).

Study 1 quantitatively assessed the immediate and six-month-post intervention impact of receiving six-months of MI, administered via CALC skills, on weight and waist circumference and psycho-social outcomes of eight women struggling with obesity. Study 2 qualitatively assessed participants’ and the volunteer CPCC’s experience of the intervention. The purpose of Study 3 was to develop a comprehensive, …