Medicine and Health Sciences Commons^™

Three-Year Trajectories Of Global Perceived Quality Of Life For Youth With Chronic Health Conditions, Janette Mcdougall, David J. Dewit, Megan Nichols, Linda Miller, F. Virginia Wright

Occupational Therapy Publications

Purpose Objectives of this longitudinal study were to examine 3-year trajectories of global perceived quality of life (QOL) for youth with chronic health conditions, as obtained from youth and parent reports, and to identify personal and environmental factors associated with the trajectory groups for each perspective.

Methods Youth with various chronic conditions aged 11–17 years and one of their parents were recruited from eight children’s treatment centers. Latent class growth analysis was used to investigate perceived QOL trajectories (separately for youth and parent perspectives) over a 3-year period (four data collection time points spaced 12 months apart). Multinomial logistic regression …

Effects Of Acute And Chronic Interval Sprint Exercise Performed On A Manually Propelled Treadmill On Upper Limb Vascular Mechanics In Healthy Young Men, T. Dylan Olver, Steph M. Reid, Alan R. Smith, Mair Zamir, Peter W.R. Lemon, M. Harold Laughlin, J. Kevin Shoemaker

Bone and Joint Institute

© 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society. Interval sprint exercise performed on a manually propelled treadmill, where the hands grip the handle bars, engages lower and upper limb skeletal muscle, but little is known regarding the effects of this exercise modality on the upper limb vasculature. We tested the hypotheses that an acute bout of sprint exercise and 6 weeks of training induces brachial artery (BA) and forearm vascular remodeling, favoring a more compliant system. Before and following a single bout of exercise as well …

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 …

Impact Of Long-Term Endurance Training Vs. Guideline-Based Physical Activity On Brain Structure In Healthy Aging, Katelyn N. Wood, Robert Nikolov, J. Kevin Shoemaker

Bone and Joint Institute

© 2016 Wood, Nikolov and Shoemaker. Brain structure is a fundamental determinant of brain function, both of which decline with age in the adult. Whereas short-term exercise improves brain size in older adults, the impact of endurance training on brain structure when initiated early and sustained throughout life, remains unknown. We tested the hypothesis that long-term competitive aerobic training enhances cortical and subcortical mass compared to middle to older-aged healthy adults who adhere to the minimum physical activity guidelines. Observations were made in 16 masters athletes (MA; 53 ± 6 years, VO2max = 55 ± 10 ml/kg/min, training > 15 years), …

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 …

Outcomes Of Unilateral And Bilateral Total Knee Arthroplasty In 238,373 Patients, Eric R. Bohm, Katy Molodianovitsh, Alina Dragan, Naisu Zhu, Greg Webster, Bas Masri, Emil Schemitsch, Michael Dunbar

Bone and Joint Institute

© 2016 The Author(s). Published by Taylor & Francis on behalf of the Nordic Orthopedic Federation. Background and purpose — There is no consensus about the outcome of simultaneous vs. staged bilateral total knee arthroplasty (TKA). We examined this issue by analyzing 238,373 patients. Patients and methods — Demographic, clinical, and outcome data were evaluated for TKA patients (unilateral: 206,771; simultaneous bilateral: 6,349; staged bilateral: 25,253) from the Canadian Hospital Morbidity Database for fiscal years 2006–2007 to 2012–2013. Outcomes were adjusted for age, sex, comorbidities, and hospital TKA volume. Results — Simultaneous bilateral TKA patients were younger than staged bilateral …

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 …

Total Versus Partial Splenectomy In Pediatric Hereditary Spherocytosis: A Systematic Review And Meta-Analysis, Leonardo Guizzetti

Epidemiology and Biostatistics Publications

To compare the clinical effectiveness of total (TS) or partial (PS) splenectomy in pediatric hereditary spherocytosis, a systematic review and meta-analysis was performed (PROSPERO registration CRD42015030056). There were 14 observational studies comparing pre- and post- operative hematologic parameters. Secondary outcomes include in-hospital infections, surgical complications, symptomatic recurrence and biliary disease. TS is more effective than PS to increase hemoglobin (3.6 g/dL vs 2.2 g/dL) and reduce reticulocytes (12.5% vs 6.5%) after one year; outcomes following PS are stable for at least 6 years. There were no cases of overwhelming post-splenectomy sepsis. A population-based patient registry is needed for long-term follow-up.

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 …

Insights Into Quasar Uv Spectra Using Unsupervised Clustering Analysis, A Tammour, S.C. Gallagher, M Daley, G.T. Richards

Brain and Mind Institute Researchers' Publications

Machine learning techniques can provide powerful tools to detect patterns in multidimensional parameter space. We use K-means - a simple yet powerful unsupervised clustering algorithm which picks out structure in unlabelled data - to study a sample of quasar UV spectra from the Quasar Catalog of the 10th Data Release of the Sloan Digital Sky Survey (SDSS-DR10) of Paris et al. Detecting patterns in large data sets helps us gain insights into the physical conditions and processes giving rise to the observed properties of quasars. We use K-means to find clusters in the parameter space of the equivalent width (EW), …

Generation Of Organ-Conditioned Media And Applications For Studying Organ-Specific Influences On Breast Cancer Metastatic Behavior, Matthew M. Piaseczny, Graciella M. Pio, Jenny E. Chu, Ying Xia, Kim Nguyen, David Goodale, Alison Allan

Anatomy and Cell Biology Publications

Breast cancer preferentially metastasizes to the lymph node, bone, lung, brain and liver in breast cancer patients. Previous research efforts have focused on identifying factors inherent to breast cancer cells that are responsible for this observed metastatic pattern (termed organ tropism), however much less is known about factors present within specific organs that contribute to this process. This is in part because of a lack of in vitro model systems that accurately recapitulate the organ microenvironment. To address this, an ex vivo model system has been established that allows for the study of soluble factors present within different organ microenvironments. …

Associative Spike Timing-Dependent Potentiation Of The Basal Dendritic Excitatory Synapses In The Hippocampus In Vivo., Thomas K Fung, Clayton S Law, L Stan Leung

Physiology and Pharmacology Publications

Spike timing-dependent plasticity in the hippocampus has rarely been studied in vivo. Using extracellular potential and current source density analysis in urethane-anesthetized adult rats, we studied synaptic plasticity at the basal dendritic excitatory synapse in CA1 after excitation-spike (ES) pairing; E was a weak basal dendritic excitation evoked by stratum oriens stimulation, and S was a population spike evoked by stratum radiatum apical dendritic excitation. We hypothesize that positive ES pairing-generating synaptic excitation before a spike-results in long-term potentiation (LTP) while negative ES pairing results in long-term depression (LTD). Pairing (50 pairs at 5 Hz) at ES intervals of -10 …

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 …

Organisational Improvement Plan: System Of Care, Derek Haime

The Dissertation-in-Practice at Western University

This organizational improvement plan (OIP) describes a way to develop and implement a system of care philosophy within a district school board with the intent of spreading this philosophy throughout the district, province, and country in the future. It is intended to be used as a tool to guide other district school boards interested in implementing a system of care. More specifically, the problem of practice this OIP is intended to address is as follows: “The current model of care for JK-8 students with mental health needs must improve. The service delivery system and pathways to treatment for child and …

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 …

Myocardial Infarction In Neonatal Mice, A Model Of Cardiac Regeneration, Jessica N. Blom, Xiangru Lu, Paul Arnold, Qingping Feng

Paediatrics Publications

Myocardial infarction induced by coronary artery ligation has been used in many animal models as a tool to study the mechanisms of cardiac repair and regeneration, and to define new targets for therapeutics. For decades, models of complete heart regeneration existed in amphibians and fish, but a mammalian counterpart was not available. The recent discovery of a postnatal window during which mice possess regenerative capabilities has led to the establishment of a mammalian model of cardiac regeneration. A surgical model of mammalian cardiac regeneration in the neonatal mouse is presented herein. Briefly, postnatal day 1 (P1) mice are anesthetized by …

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, …

Rural Men’S Health, Health Information Seeking, And Gender Identities: A Conceptual Theoretical Review Of The Literature, Bradley C. Hiebert, Beverly Leipert, Sandra Regan, Jacquelyn A. Burkell

FIMS Publications

Beginning as early as 2009, recent shifts in Canadian health care delivery indicate that access to health information is essential to promote and maintain a healthy population. It is important to understand how and where various populations, such as underresourced rural populations, access health information so that public health agencies can develop and deliver appropriate information with, for, and in these contexts. There is a paucity of research that specifically examines how rural Canadian men seek health information; therefore, this review aimed to conceptualize this process based on three dynamic key constructs: health patterns of rural Canadians, health information–seeking behaviors, …

The Neural Roots Of Mathematical Expertise, Daniel Ansari

Brain and Mind Institute Researchers' Publications

No abstract provided.

Hip Fracture Types In Canadian Men And Women Change Differently With Age: A Population-Level Analysis, Richard G. Crilly, Marita Kloseck, Selam Mequanint

Bone and Joint Institute

© the authors, publisher and licensee Libertas Academica Limited. Background: We have previously reported a gender difference in the occurrence of hip fracture type with age in our local population. In the current report, we have explored this phenomenon in a Canadian population using five years of data from a national administrative database. We have com-pared community-dwelling and institutionalized individuals to determine if frailty is important and has a differential effect on the type of hip fracture experienced.Methods: Hospitalization records from 2005 to 2009, in which the most responsible diagnosis, that is the diagnosis causing the admission to hospital, was …

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 …