Medicine and Health Sciences Commons^™

Regulation Of Phosphatase And Tensin Homolog Expression And Activity By Transforming Growth-Factor Beta In The Trabecular Meshwork Cells: Implications For Primary Open Angle Glaucoma, Nikoleta Tellios

Electronic Thesis and Dissertation Repository

Glaucoma is a multifactorial condition caused, in part, by fibrosis of the sieve-like trabecular meshwork (TM) tissue, which impedes drainage of aqueous humor (AH), leading to increased intraocular pressure and associated optic nerve damage and blindness. Fibrosis of the TM is mainly caused by the increased levels of active transforming growth factor-β 2 (TGFβ2) in the AH of glaucoma patients.

Previous reports have shown that TGFβ decreases the expression of Phosphatase and Tensin Homolog (PTEN) gene and that PTEN is a major regulator of ECM deposition. In this study we investigate the regulation of PTEN protein expression and …

The Association Between Social Cohesion And Physical Activity In Communities Across Canada: A Multilevel Analysis, Calvin Yip

Electronic Thesis and Dissertation Repository

Background: In Canada, only 15% of adults meet physical activity guidelines for optimal health. Previous research has suggested that social cohesion may promote physical activity.

Objective: To assess the association between social cohesion and physical activity among adults aged 18 to 64 years in Canada.

Methods: Data from the 2009-2010, 2011-2012, and 2013-2014 cycles (N=245,150) of the Canadian Community Health Survey were used. Physical activity level was operationalized using average daily energy expenditure, social cohesion was determined by self-rated sense of belonging to the local community, and communities were represented by Canada’s Forward Sortation Areas. Multilevel regression models were used …

Non-Invasive Imaging For The Assessment Of Cardiac Dose And Function Following Focused External Beam Irradiation, Omar El-Sherif

Electronic Thesis and Dissertation Repository

Technological advances in imaging and radiotherapy have led to significant improvement in the survival rate of breast cancer patients. However, a larger proportion of patients are now exhibiting the less understood, latent effects of incidental cardiac irradiation that occurs during left-sided breast radiotherapy. Here, we examine the utility of four-dimensional computed tomography (4D-CT) for the accurate assessment of cardiac dose; and a hybrid positron emission tomography (PET) magnetic resonance imaging (MRI) system to longitudinally study radiation-induced cardiac effects in a canine model.

Using 4D-CT and deformable dose accumulation, we assessed the variation caused by breathing motion in the estimated dose …

Peroxisome Proliferator Activated Receptor Delta In Osteoarthritis, Anusha Ratneswaran

Electronic Thesis and Dissertation Repository

Osteoarthritis (OA) affects 1 in 10 Canadians and is a leading cause of mobility disability worldwide. This condition is characterized by cartilage degeneration, subchondral bone damage and inflammation of the synovium, resulting in pain and joint failure. No treatments exist to stop the progression of this disease, and its underlying molecular mechanisms remain largely unknown. We previously identified the peroxisome proliferator activated receptor (PPAR) nuclear receptor pathway as altered in OA cartilage. In-vitro studies identified PPARd as a promoter of catabolic activity in chondrocytes, providing the foundation for my overarching hypothesis that PPARd inhibition is protective in OA.

I commenced …

Catheter Ablation For Atrial Fibrillation: Predicting Recurrence, Kendra Thomas

Electronic Thesis and Dissertation Repository

Background

Catheter ablation has emerged as treatment for atrial fibrillation (AF). Health care-related variables have not been explored as predictors of first ablation outcome. Determining factors associated with arrhythmia recurrence may help select patients likely to benefit. The objective was to identify variables associated with recurrence following AF ablation.

Methods

Retrospective cohort design of 314 AF patients who had undergone first ablation. Follow-up visits occurred at 3, 6 and 12 months. Variables and the outcome of recurrence were modeled with Cox proportional hazards analysis.

Results/Conclusions

After mean follow-up of 239+/-125 days, 110/314 patients (35.0%) experienced recurrence. Adjusted Cox proportional hazards …

Effects Of Prenatal Exposure To Bisphenol A On Fetal Lung Development, Ayten Hijazi

Electronic Thesis and Dissertation Repository

Prenatal exposure to bisphenol A (BPA), one of the most prevalent endocrine disrupting chemicals, is associated with lung dysfunction and diseases in later life. However, it is unknown if this association has a fetal origin. In this thesis, a series of in vivo and in vitro experiments were conducted to determine the effects of prenatal exposure to BPA on fetal lung development, and define the underlying molecular mechanisms. Environmentally relevant doses of BPA were administered to pregnant mice via diet from embryonic day (E) 7.5 to 18.5. Fetal lungs were analyzed at E18.5 for changes in structure and expression of …

The Development Of Novel Imaging Modalities & High-Throughput Drug Screening Platforms In The Drosophila Melanogaster Model Of Human Calcium Oxalate Nephrolithiasis, Sohrab Naushad Ali

Electronic Thesis and Dissertation Repository

Nephrolithiasis is a common urological disorder. Despite advances in the surgical treatment of kidney stone disease, research into its prevention and medical management remain stagnant. This is due to lack of viable pre-clinical models to study the disorder. In this project, we develop and characterize a robust Drosophila melanogaster model for human calcium oxalate nephrolithiasis. Using this model, we have developed intravital imaging techniques to study stone formation and novel high-throughput drug screening platforms. We successfully demonstrate calcium oxalate stone formation by sodium oxalate and ethylene glycol supplementation, with subsequent intravital imaging using bisphosphonate based fluorescent probes. Screening of 360 …

The Relationship Between Elements Of Health And Social Systems And Substance Use Severity For Individuals Experiencing Homelessness, Sommer Froats

Electronic Thesis and Dissertation Repository

Canadians experiencing homelessness often live with severe substance use (Aubry et al., 2015; Khandor & Mason, 2007). Health challenges related to severe substance use contribute to the early mortality experienced by homeless Canadians (Hwang, Wilkins, Tjepkema, O’Campo & Dunn, 2009). This population also experience health and social system disadvantages. Using General Systems Theory, relationships between substance use severity and access to health care, housing stability, therapeutic relationship and quality of family and friends relationships were explored as elements of health and social systems. A correlational secondary analysis examined this in a sample of 65 individuals accessing housing first. Relationships were …

Visualizing And Interacting With Social Determinants Of Health, Moutasem Zakkar

Electronic Thesis and Dissertation Repository

Purpose: The purpose of this study is to examine the use of information visualization to represent specific social determinants of health, and to examine the benefits of such representation for health policymaking. Methods: The study developed a prototype for a visualization tool (www.healthvisualization.ca), which represents the conceptual framework for the social determinants of health (CSDH) and new ways to represent related health equity indicators. This tool was used by study participants. The experience of these participants and the usability of the tool were evaluated using qualitative semi-structured interviews. Results: Visualizing the CSDH framework helps to present the social …

Evaluating The Role Of Intestinal Transporters In Fruit Juice-Drug Interactions, Mandy Mj Li

Electronic Thesis and Dissertation Repository

Fruit juice-drug interactions (FJDIs) involving non-metabolized oral medications result in decreased drug exposure that may lead to reduced therapeutic efficacy. The effect is thought to be mediated by inhibition of the intestinal drug transporters organic anion transporting polypeptide 1A2 and 2B1 (OATP1A2 and OATP2B1) by fruit juice constituents, however the exact mechanisms remain controversial. We tested the hypothesis that fruit juices limit the absorption of fexofenadine through interactions with specific intestinal transporters. In vitro transport and fruit juice inhibition studies using fexofenadine, a medication involved in FJDIs, revealed that in addition to previously implicated transporters, organic cation transporter 1 (OCT1) …

Infants Born Large For Gestational Age And Developmental Attainment In Early Childhood, Cairina E. Frank

Electronic Thesis and Dissertation Repository

Birth weight is a strong predictor of neonatal health outcomes. The majority of literature has focused on those infants born SGA. Infants born LGA have been shown to be at higher risk of immediate obstetrical complications and metabolic deficits, yet less research has focused on subsequent development. This study aims to investigate whether LGA is associated with developmental attainment and to examine the attribution of upstream factors and variables along the causal pathway. Data from the NLSCY was used. LGA was defined as a BW >90^th percentile. Outcomes were poor verbal ability (scoring <15^th percentile on the PPVT-R) and …

Etiology Of Motor Vehicle Collision Fatalities In Urban And Rural Canada, James R. Roos

Electronic Thesis and Dissertation Repository

While it has been consistently demonstrated that fatal motor vehicle collision (MVC) rates are higher for rural than urban roadways, it remains to be elucidated which collision factors account for this difference. Fatal MVC rates have been demonstrated to be higher in rural locations even when controlling for age, restraint use, and vehicle speed. This study aims to assess which collision factors are most prevalent for fatal rural motor vehicle collisions, and to address how those factors differ in significance between rural and urban regions. Our study indicates that a combination of human, environmental, and vehicular factors may account for …

Acute Kidney Injury Biomarkers: A Prospective Cohort Study In Urological Patients, Daniel Olvera-Posada

Electronic Thesis and Dissertation Repository

Several recent studies have assessed the use of biomarkers of Acute Kidney Injury (AKI), but the information among patients with stone disease and those with obstructive uropathy is limited. For this reason, we conducted a prospective cohort study to determine the urinary levels of KIM-1, Total and Monomeric NGAL in patients with hydronephrosis secondary to renal stone disease, congenital ureteropelvic junction obstruction or ureteral stricture, and in a group of healthy controls in our health care center. Urinary biomarker concentrations were evaluated before and after surgical treatment. Patients with hydronephrosis showed significantly higher baseline levels of KIM-1 compared to those …

Intra-Abdominal Hypertension And Abdominal Compartment Syndrome, Patrick B. Murphy

Electronic Thesis and Dissertation Repository

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are increasingly recognized in critically ill patients; no non operative treatments exist, and mortality remains high.

The purpose of this thesis was to prospectively characterize the incidence of IAH in a mixed medical-surgical intensive care unit, and to test the potential therapeutic benefit of carbon monoxide (CO) and hydrogen sulphide (H2S) using an animal model of ACS. IAH was diagnosed in 30% of patients on admission; further 15% developed IAH during ICU stay. Incidence of ACS was 3%, with obesity, sepsis, mechanical ventilation and 24-hour fluid balance as independent predictors, also predicting …

Nurses' Workplace Social Capital: Development And Validation Of A Self-Report Questionnaire, Emily A. Read

Electronic Thesis and Dissertation Repository

Background: Social capital refers to resources created by and embedded in social relationships and has been identified as an important aspect of nurses’ work life. There is limited empirical evidence regarding its role and currently no valid and reliable self-report instruments to measure workplace social capital comprehensively.

Purpose: This study aimed to develop and test a self-report questionnaire to measure nurses’ workplace social capital and examine the nomologicial network of the concept including authentic leadership and structural empowerment as precursors of social capital and team effectiveness and patient care quality as outcomes.

Methods: A cross-sectional survey of 1,000 Registered Nurses …

The Effects Of Empowerment On Role Competency And Patient Safety Competency For Newly Graduated Nurse Practitioners, Elsie Duff

Electronic Thesis and Dissertation Repository

Introduction: Role competence and patient safety (PS) competence among healthcare professionals are rapidly developing issues due to increasing patient acuity and complexity in the healthcare system. Upon graduation, nurse practitioners (NPs) provide autonomous healthcare for populations with complex health needs, thus role and PS competence is imperative. In Canada, few studies have examined NP education and role development specific to NP role competence and PS competencies. This study addresses this gap in the research examining educational experiences of new NP graduates.

Aim: The aim of this study is to test a hypothesized model of the relationships between educational structural empowerment, …

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 …

Uprootedness And Health Of Women Temporary Agricultural Workers: A Critical Ethnography, Kathryn Ann Edmunds

Electronic Thesis and Dissertation Repository

In recent years, increased global mobility for work, gendered approaches to migration, and the vulnerabilities of women in temporary and precarious work have received increased attention. However, there is limited evidence regarding the health of women temporary foreign workers in Canadian agriculture. The purposes of this critical ethnography using feminist and intersectional perspectives were to: 1) explore and describe women temporary agricultural workers’ experiences and meanings of health in the context of prolonged and repeated uprootedness from their homes and families, 2) to critically examine how the intersections of current gendered, global, political and economic conditions shaped their everyday lives …

Platelet Rich Plasma In Musculoskeletal Pathologies, Nicole L. Kaniki

Electronic Thesis and Dissertation Repository

Purpose: To evaluate the effectiveness of platelet rich plasma (PRP) in musculoskeletal injuries.

Methods: We completed a review of the literature on the use of PRP in tendon, muscle, bone, and intra-articular injuries (Chapter 2). We completed a systematic review and meta-analysis on the effectiveness of PRP in ultrasound guided versus palpation guided injections of PRP in non-operative treatment of tendon and muscle injuries using an indirect analysis method (Chapter 3). We conducted a randomized controlled trial to determine the effectiveness of PRP versus corticosteroid (CS) injections in patients with plantar fasciitis (Chapter 4).

Results: Most studies …

Oncolytic Virus Therapy For The Treatment Of Metastatic Ovarian Cancer, Jessica Tong

Electronic Thesis and Dissertation Repository

The management of patients with epithelial ovarian cancer (EOC) faces two major challenges which standard treatments fail to effectively address: 1) Diffuse metastasis as a consequence of late stage diagnosis and 2) intra-tumoral heterogeneity, which fuels tumor evolution and drives the acquisition of chemotherapeutic resistance. In this thesis, we tested new therapeutic strategies using a 3-dimensional in vitro spheroid culture model that mimics key steps of epithelial ovarian cancer metastasis; and another model that mimics both temporal and cellular heterogeneity by establishing multiple cell lines from a single patient over the course of disease progression. Using these models, we investigated …

First-Responders And Emergency Department Healthcare Provider Interactions During Emergency Situations: A Grounded Theory Study, Jennifer A. Mohaupt

Electronic Thesis and Dissertation Repository

Interactions between and among first-responders and emergency department (ED) healthcare providers impact the way in which patients are managed during emergency situations. The purpose of this study was to develop a grounded theory to explain the interactions between and among first-responders and ED healthcare providers during emergency situations. Interprofessional collaboration and teamwork has been extensively studied, however little is known about interactions that include first-responders. This study was guided by Strauss and Corbin’s (1990) approach to grounded theory. Data were collected through 256 hours of first-responder and ED observational opportunities and informal interviews with accompanying detailed field notes. As well, …

Markerless Radiostereogammetry Of The Shoulder Joint In Humans: Comparisons Of Scapulohumeral Kinematics Between Individuals With Healthy And Supraspinatus-Impaired Shoulders, Ashley N. Hannon

Electronic Thesis and Dissertation Repository

The purpose of this collection of studies was to further develop the knowledge of shoulder motion in order to better understand joint function through direct measurement of 3D scapulohumeral joint kinematics using a technique of high accuracy. Markerless, bi-planar fluoroscopic radiostereometric analysis using a generic shoulder model was developed in this thesis, reducing the amount of radiation exposure to subjects. The studies compared kinematic data of the scapulohumeral joint in six degrees of freedom with a precise, in-vivo measuring technique. Data were collected on young and older healthy individuals, individuals with a torn supraspinatus and post-surgical intervention.

Although this generic …

Arthrokinematics Of The Distal Radioulnar Joint In The Normal Wrist And Following Distal Radius Malunion, Braden M. Gammon

Electronic Thesis and Dissertation Repository

Contact patterns in the distal radioulnar joint (DRUJ) are not well understood for normal anatomy or with distal radius deformity. This thesis presents three studies which investigate the arthrokinematics of the DRUJ for these conditions. The first study compared casting and Tekscan, two standard methods for contact measurement, with a novel technique of proximity mapping termed Inter-cartilage Distance (ICD). The relative benefits, limitations and role for ICD in DRUJ contact assessment were examined and discussed. The second study used ICD to characterize contact patterns in the native DRUJ. Contact was found to be maximal in 10 degrees of supination and …

The Euthanasia Debate: International Experience And Canadian Policy Proposals, Lorna M. Fratschko

Electronic Thesis and Dissertation Repository

This thesis examines the problematic prospect of the introduction of euthanasia and physician-assisted suicide into Canadian society. The thesis argues that euthanasia is too simplistic an approach to address the complexities of end of life issues. The policy proposal under active discussion is profoundly mistaken. The language of euthanasia is examined in relation to the choice of words used, drawing attention to how words, when used loosely, can distort reality in this matter. Historical experience from other jurisdictions is presented to provide a context for this discussion. A "slippery slope" argument emerges via the claim that, in practice and in …

Angiogenic Therapy In A Fibrotic Murine Model Of Duchenne Muscular Dystrophy, Kelly M. Gutpell

Electronic Thesis and Dissertation Repository

Duchenne muscular dystrophy (DMD) is a devastating neuromuscular disorder that affects approximately 1 in 5000 males. Vascular-targeted therapy has been proposed as a treatment for DMD to reduce ischemia and enhance endogenous repair. Additionally, a more vascularized environment may enhance regenerative approaches currently under investigation. Vascular endothelial growth factor (VEGF) and angiopoietin-1 (ANG1) are two of the most studied pro-angiogenic factors for this approach. To date, little is known regarding the effect of these pro-angiogenic factors on muscle function and whether they may exacerbate fibrosis in a relevant murine model of DMD. The first aim of this thesis was to …

Machine Learning Of Lifestyle Data For Diabetes, Yan Luo

Electronic Thesis and Dissertation Repository

Self-Monitoring of Blood Glucose (SMBG) for Type-2 Diabetes (T2D) remains highly challenging for both patients and doctors due to the complexities of diabetic lifestyle data logging and insufficient short-term and personalized recommendations/advice. The recent mobile diabetes management systems have been proved clinically effective to facilitate self-management. However, most such systems have poor usability and are limited in data analytic functionalities. These two challenges are connected and affected by each other. The ease of data recording brings better data for applicable data analytic algorithms. On the other hand, the irrelevant or inaccurate data input will certainly commit errors and noises. The …

Exploring The Mobile Phone Digital Divide Among Individuals Experiencing Mental Illness: A Secondary Analysis, Jefferey R. Reed

Electronic Thesis and Dissertation Repository

ABSTRACT

Aim: To test van Dijk’s (2005) Framework for Understanding the Digital Divide. This framework examines social inequalities that influence the phenomenon of the digital divide and the implications it has upon social participation for individuals with mental illness.

Background: Mental illness is the second leading cause of disability and premature death, and constitutes more than 15% of the burden of disease in Canada (Centre for Addiction and Mental Health, 2012). Mobile phones may be useful in promoting health and social wellness among this population. It is unclear whether these individuals face disparities in the access to and use of …

Characterization Of Microbial Communities In The Mammary Glands And The Influence Of This Microbiota On Health And Disease, Camilla Urbaniak

Electronic Thesis and Dissertation Repository

The collective microbes and their genomic activity within us, referred to as the human microbiome, is crucial in maintaining health, and disruptions in composition and activity have been associated with various diseases. Considering the importance of breast milk in neonatal development and the high rate of breast cancer in women, the objective of my thesis was to obtain a comprehensive analysis of the microbiota of the mammary glands and to examine the influence of these organisms on health and disease.

Human milk is an important source of bacteria for the developing infant. While a variety of studies over the last …

Optimizing The Rehabilitation Of Elbow Lateral Collateral Ligament Injuries, Ranita Harpreet Kaur Manocha

Electronic Thesis and Dissertation Repository

Elbow lateral collateral ligament (LCL) injuries frequently arise following trauma, and can result in disabling instability. Typically such injuries are managed with immobilization followed by a graduated exercise regime; however there is minimal biomechanical evidence to support current treatment protocols. This investigation examines the in vitro effectiveness of several rehabilitation techniques using a custom elbow motion simulator. It was found that active range of motion is safest in the overhead position (n = 7). Early motion in this position may reduce the incidence of elbow stiffness without compromising ligament healing following LCL injury. Forearm pronation and active motion stabilize …

A Study To Understand And Compare Evidence Based Practice Among Health Professionals Involved In Pain Management, Vanitha Arumugam

Electronic Thesis and Dissertation Repository

Pain management is a common concern of multiple health professionals. Evidence-based practice (EBP) in pain management is a recognized approach used to improve health outcomes. EBP tools can facilitate its implementation. PAIN⁺ is a tool that provides access to pre-appraised current best research evidence on pain to support clinical decisions. It is important to understand the knowledge, attitudes and behavior of professionals towards EBP and more specifically how they access research about pain management.

The overarching purpose of this thesis is to better understand how clinicians from different professions involved in pain management view EBP and implement specific strategies …