Medicine and Health Sciences Commons^™

Exploring Multimodal Cancer Cell Tracking Using Magnetic Particle Imaging And Akaluc Bli, Ryan J. Williams

Electronic Thesis and Dissertation Repository

Magnetic Particle Imaging (MPI), a novel imaging technology, offers hotspot visualization and quantification of superparamagnetic iron oxide (SPIO) labelled cells in vivo. Bioluminescence imaging (BLI), with the sensitive reporter Akaluc, can provide complementary information on cell viability and proliferation. Here, we combined MPI, and Akaluc BLI for a more holistic picture of cancer cell fate in mice. Breast cancer cells labelled with Akaluc and the SPIO Synomag-D, were injected into the mammary fat pad (MFP) of mice and imaged on BLI and MPI for 2-weeks. Over this period, BLI signal increased due to tumour progression, while MPI signal decreased due …

Improving Developing Countries’ Health Information Systems Capacity For Infectious Disease Pandemic Responses: A Case Study Of The Ebola Virus Disease And The Coronavirus Disease Pandemics, Uche Ikenyei

Electronic Thesis and Dissertation Repository

There is increasing evidence to demonstrate that current information system theoretical models meant to assess the success of the health information systems (HIS) lack the applicable theoretical underpinning suitable for developing countries. This stems partly from a theory-evidence gap where theoretical models developed in the West are applied in developing country contexts but lack tailoring to localized, contextual realities. Therefore, this study addresses this gap by enhancing the DeLeon and McLean's information system success model with six contextual factors peculiar to the infectious disease HISs in a developing country context.

This study took place in two developing countries, Liberia and …

Biomechanical Analysis Of Ligament Modelling Techniques And Femoral Component Malrotation Following Tka, Liam A. Montgomery

Electronic Thesis and Dissertation Repository

Previous studies have demonstrated that satisfaction and revision rates following total knee arthroplasty (TKA) are lower than those of comparable surgeries such as total hip replacements. A leading cause for these revisions is joint instability which may be due to improper ligament balancing or poorly aligned surgical implants. One of the methods used to investigate biomechanical forces and kinematics is computational modelling of the post-operative TKA knee.

A unique knee model was used to investigate the biomechanical and kinematic effects of ligament model complexity, as well as the effects of simulating ligament wrapping versus ignoring ligament wrapping. We then used …

Effect Of Levodopa On Eeg Connectivity In Parkinson's Patients, Sepehr Torab Parhiz

Electronic Thesis and Dissertation Repository

Levodopa is a dopamine replacement medication administered to patients with Parkinson’s disease (PD) to alleviate their motor symptoms. However, its long-term use can cause adverse side effects, including involuntary motor movements. We studied 16 PD patients before and after taking Levodopa based on resting-state electroencephalography (EEG) recordings to determine how Levodopa affects the functional connectivity of their brain networks. We used several metrics from graph theory, in particular the minimum spanning tree (MST) metric, and analyzed how they change after subjects take Levodopa. We observed significant changes in the lower alpha band toward a more path-like and less globally efficient …

Validation Of The Flexcell®Fx-5000 Tension System To Evaluate The Expression Of Cementum Protein-1 In Human Periodontal Ligament Cells While Under Cyclical Orthodontic Tensile Force, Allison Nicholls

Electronic Thesis and Dissertation Repository

The pressure-tension theory of orthodontic tooth movement (OTM) states that there are differences in microenvironment between the tension and compressions side within the periodontal ligament, leading to differential gene expression within those zones. Cementum protein 1 (CEMP-1) is a human-specific protein localized to the root of a tooth and may play a role in OTM. The first objective was to develop a protocol to apply tensile force to human PDL cells similar to that within the tension zone during OTM. For this, the FlexCell®FX-5000 Tension system was used and fluorescent microscopy was used to confirm validity of the protocol. The …

Consideration Of Executive Functioning For Physiotherapy Rehabilitation: Studies Of Physiotherapists’ Knowledge, Normative Data, And A Practice Application, Nicole A. Guitar

Electronic Thesis and Dissertation Repository

Executive functioning (EF) refers to cognitive abilities involved in decision-making and self-regulation and can be impaired in many patients referred for physiotherapy, including older adults and people living with chronic pain. This dissertation aimed to determine what physiotherapists understood about EF, to summarize normative data for application in physiotherapy practice, and to provide an assessment of feasibility for studying EF impairments in people living with chronic pain. Study one surveyed what physiotherapists understood about EF as a concept, what EF assessments they used, and if this was influenced by their primary area of practice. Respondents (N = 262) subjectively reported …

Investigating A Novel Receptor That Mediates Vasoconstriction In Mouse Femoral Arteries, Joselia Carlos

Electronic Thesis and Dissertation Repository

The synthetic peptide trans-cinnamoyl-leucine-isoleucine-glycine-arginine-leucine-ornithine-amide (tcLIGRLO) causes smooth muscle contraction in mouse femoral arteries. The identity of the receptor that mediates this response is undetermined. We hypothesize that the novel mechanism for tcLIGRLO-induced contractions involves a G-protein coupled receptor (GPCR) and a G_q-Ca²⁺ signalling pathway. Chapter 2 describes experiments using femoral arteries isolated from male and female systemic protease-activated receptor 2 (PAR2KO) mice (n=31; 21 – 39 weeks of age) using tcLIGRLO and the G_q-inhibitor, YM-254890 (YM). Contractions produced by tcLIGRLO did not differ by sex but decreased as age increased. YM inhibited tcLIGRLO-induced contractions. Chapter …

Applications Of Genetic Testing For Endocrine And Metabolic Disorders, Amanda Berberich

Electronic Thesis and Dissertation Repository

Knowledge of inherited diseases and the ability to rapidly, efficiently and comprehensively perform genetic testing are advancing steadily. However, the ideal approach to translate this ability into clinical applications for endocrine disorders has yet to be determined. This work focuses on aspects of clinically translating knowledge of select heritable endocrine and metabolic conditions.

For maturity onset diabetes of the young (MODY), a monogenic disorder with no current consensus guidelines governing testing procedures, this work addresses methods to improve detection by validating the use of next generation sequencing-based techniques to identify MODY cases and to detect copy number variations.

For very …

Endothelial Dysfunction In Hindlimb Arteries Of Old Sprague Dawley Rats, And The Type 2 Diabetic Zucker Diabetic Sprague Dawley Strain., Andrea N. Wang

Electronic Thesis and Dissertation Repository

Ageing, and type 2 diabetes are associated with cardiovascular diseases and endothelial dysfunction. Endothelial dysfunction is characterized by a decline in endothelium-mediated vasodilation. In this thesis, we determined the vascular function of hindlimb arteries supplying skeletal muscle and extremities using isolated arteries and wire myography. For ageing studies, we used Sprague Dawley rats and for type 2 diabetes we used the Zucker Diabetic Sprague Dawley strain. Vasodilation of hindlimb arteries with acetylcholine were impaired in both models. However, protease-activated receptor 2 mediated vasodilation was upregulated in arteries. Evidence of non-nitric oxide mechanisms were also found in peripheral vasculature. These data …

Effects Of Annexin A5 On Endothelial Inflammation Induced By Lipopolysaccharide-Activated Platelets And Extracellular Vesicles, Brent Jeffrey Tschirhart

Electronic Thesis and Dissertation Repository

Sepsis is a dysregulated immune response to infection and the leading cause of mortality globally, accounting for 11 million deaths in 2017. To date, no therapeutics are available to treat the underlying septic response. Previous research from our laboratory has shown that annexin A5 (Anx5) treatment increased survival by 40% in mice with endotoxemia, a model of sepsis. During sepsis, activated platelets release membrane fragments called extracellular vesicles (EVs) with externalization of phosphatidylserine to which annexin A5 binds with a high affinity. We hypothesized that annexin A5 will block the pro-inflammatory response induced by activated platelets and EVs in vascular …

The Role Of Exogenous Ketones On Various Aspects Of Exercise Performance, Manuel D. Quinones

Electronic Thesis and Dissertation Repository

Routinely, athletes and coaches pursue novel nutritional strategies in an attempt to support exercise training techniques and/or enhance athletic performance. Body carbohydrate (CHO) stores are limited so strategies to enhance fat use and spare CHO during exercise and thus, attenuate the onset of fatigue are commonplace. It has been suggested that oral exogenous ketone administration is ergogenic not only by altering exercise metabolism (sparing CHO), but also by improving exercise cognitive function as well as enhancing post-exercise glycogen resynthesis. However, data supporting these claims are limited and contradictory. Therefore, the purpose of this dissertation was to explore the role of …

Kindlin-1 Is Involved In Spreading, Migration, And Protein Regulation In Epidermal Scc-13 Cells, Naomi Mishan

Electronic Thesis and Dissertation Repository

Kindlin-1 is a scaffold protein linking the cytoskeleton to the extracellular matrix. Loss of function mutations in the FERMT1 gene (encoding Kindlin-1) cause gastrointestinal and skin defects associated with increased susceptibility to aggressive epidermal squamous cell carcinoma (SCC). This study investigated the consequences of targeted FERMT1 inactivation in the SCC-13 cell line of epidermal SCC. My studies demonstrate Kindlin-1 is not essential for SCC-13 proliferation or clonogenic potential in culture. Kindlin-1 was required for cell spreading on collagen I, but not on laminin-332, and its absence enhanced SCC-13 directional migration. Finally, I identified several proteins involved in tumor formation and …

Health Providers Perspectives On The Access And Use Of Formal Health And Social Services By Stroke Caregivers, Hannah Pollock

Electronic Thesis and Dissertation Repository

Informal stroke caregivers, comprised of family and friends, can experience prolonged stress that places them at risk of poor health and social outcomes. These caregivers may benefit from formal health and social services, but they are often underused and challenging to access. This qualitative interpretive description study sought to explore health providers’ perspectives on the factors that impact stroke caregivers' access and use of formal health and social services. In addition, it sought to explore health providers' experiences and how they perceive their role in supporting stroke caregivers'. In-depth, semi-structured interviews were conducted with 18 health providers. Through inductive thematic …

Falls Screening In Community- Dwelling Older Adults, Hadi Kooshiar

Electronic Thesis and Dissertation Repository

Falls screening can prevent falls and their consequences. The two studies of this thesis aimed to identify the accuracy of falls screening tools and explore patient preferences and empirical validity of the self-rated Falls Risk Questionnaire (FRQ). The first study, Systematic Literature Review, found the Toulouse-St. Louis University Mini Falls Assessment and the Activities-specific Balance Confidence scale Hindi version emerged as accurate tools for predicting falls in the target population. The second study determined most of respondents, 36%, had no preference between Activities Specific Balance Confidence 6 items (ABC-6) or FRQ. The Bland & Altman approach revealed a degree of …

The Development, Short-Term Efficacy, And Pilot Implementation Of An E-Learning Course In Physical Activity And Sedentary Behaviour For Pre-Service Early Childhood Educators, Brianne Bruijns

Electronic Thesis and Dissertation Repository

The overarching purpose of this dissertation was to develop an e-Learning course in physical activity and sedentary behaviour and test its short-term efficacy and implementation among pre- and in-service early childhood educators (ECEs). The Delphi approach was adopted for Study 1, wherein a panel of international experts in physical activity and sedentary behaviour suggested topics for the course and, together with a panel of ECE experts, rated their importance. Study 2 employed a pre-post design to explore the changes in pre- and in-service ECEs’ physical activity and sedentary behaviour-related knowledge, self-efficacy, behavioural intention, and perceived behavioural control following course completion. …

Exploring The Perspectives Of Older Adults And Health Care Providers On Patient Participation In Transitional Care From Hospital To Cardiac Rehabilitation During The Covid-19 Pandemic, Cecilia Flores Sandoval

Electronic Thesis and Dissertation Repository

Older adults who transition from hospital to cardiac rehabilitation settings often are vulnerable and at risk of experiencing adverse health care outcomes. Given the complexities of transitional care, it is crucial to engage older adults in the clinical decision-making process and to promote their active participation in their medical care. Older adults have unique ways of understanding their participation in the transitional care process. Gaining an in-depth understanding of their specific needs during this process can help inform clinical practice and interventions aiming to improve care for older adults living with cardiovascular disease. Focused ethnography methodology was used to explore …

Understanding The Lived Experience Of Health Through The Exploration Of Well-Being Of Women With Multiple Sclerosis In Southwestern Ontario, Jennifer Howard

Electronic Thesis and Dissertation Repository

The prevalence of Multiple Sclerosis (MS) is increasing globally with 2.8 million cases worldwide as of 2021, with Canada experiencing the highest incidence for this disease (Multiple Sclerosis International Foundation [MSIF], 2021; Multiple Sclerosis Society of Canada [MSSC], 2021). MS is an autoimmune disease that damages the myelin sheath in the central nervous system (spinal cord and brain) which may result in problematic symptoms such as cognitive dysfunction and lead to physical disability (MSSC, 2021). There are over 90,000 Canadians with MS, impacting women on a ratio of 3:1 compared to men (MSSC, 2021; Statistics Canada, 2013). Current literature suggests …

A Characterization Of Rgnef Biophysical Properties And Interactome, Brooke E. Wile

Electronic Thesis and Dissertation Repository

ALS is a progressive and fatal neurodegenerative disorder whose pathologic hallmark is the presence of neuronal cytoplasmic inclusions (NCIs). In approximately 97% of ALS cases, NCIs are found to be TDP-43+. Rho-guanine nucleotide exchange factor (RGNEF) has recently been implicated in ALS pathophysiology through its co-localization and coimmunoprecipitation with TDP-43+. RGNEF has also been shown to harbour cytoprotective effects in the N-terminal region and is responsible for the regulation of low molecular weight-neurofilament (NFL), intimately involved neural structure, through its predicted RNA-binding domain (RBD). This study looked to purify constructs of RGNEF through nickel immobilized metal affinity chromatography (Ni-IMAC) and …

Femoroacetabular Impingement Syndrome: Evaluating Postoperative Rehabilitation Progress And Return To Sport Readiness, Trevor A. Day

Electronic Thesis and Dissertation Repository

Femoroacetabular impingement syndrome (FAIS) is a common cause of non-arthritic hip pain and reduced physical activity in active young adults. It is defined as a motion-related disorder of the hip with a triad of symptoms, clinical signs, and imaging findings that represents symptomatic premature contact between the proximal femur and the acetabulum. There are two anatomical morphologies that can cause FAIS, cam, and pincer, and is a challenging clinical pathology. Patients typically undergo hip arthroscopy to repair damage to the joint and recess the bone causing the impingement. These procedures can result in positive outcomes for the patient, like reduced …

The Role Of Working Memory And Linguistic Knowledge On Language Performance, Theresa Ai Vy Pham

Electronic Thesis and Dissertation Repository

The language system is highly flexible and draws on distinct but interconnected cognitive mechanisms, including verbal working memory and long-term linguistic knowledge. Verbal working memory is the ability to manipulate verbal information in mind. Long-term linguistic knowledge refers to our knowledge of the language (i.e., phonology, semantics, syntax), stored in long-term memory. The close interaction between verbal working memory and linguistic knowledge highlights a pressing need to investigate the construct of verbal working memory, its separability and its relationship with linguistic knowledge. To understand the way working memory influences and interacts with language abilities in children and adults, I ask …

New Graduate Nurses’ Experiences Of Engaging In A Leadership Role In Hospital Settings During The Covid-19 Pandemic, Justine Jeanelle Ting

Electronic Thesis and Dissertation Repository

New graduate registered nurses are often expected to assume leadership roles and responsibilities quickly upon entering practice. Since the emergence of the COVID-19 pandemic, new nurses may find their leadership capabilities tested even further as the demands of leadership have been made increasingly complex in the context of an infectious disease outbreak. The purpose of this interpretive descriptive study was to explore new graduate registered nurses’ experiences of engaging in frontline leadership roles in hospital settings during the COVID-19 pandemic. In-depth interviews were conducted with 14 participants across Ontario. Content analysis revealed four main themes: nominated and necessitated into leadership …

Reddit And Nursing During Covid-19: A Summative Content Analysis, Julia C. Savin

Electronic Thesis and Dissertation Repository

Purpose: The purpose of this thesis was to explore what self-identified nurses discussed on the nursing SubReddit during the Covid-19 pandemic between March 2020 to May 2020.

Methods: The Hsieh and Shannon (2005) summative content analysis with emergent categorical development was used to categorize the naturalistic data.

Findings: Through analysis, six content categories were identified from the nursing SubReddit: (a) employers’ approaches to the pandemic; (b) emergency preparedness in response to the pandemic; (c) shared experiences; (d) nursing students and new graduate nurses; (e) coping; and, (f) gratitude to nurses.

Implications: (a) Leadership that is communication-focused will improve the quality …

Understanding The Current State Of Health Information Exchange In Long-Term Care Homes, Kendra R. Cotton

Electronic Thesis and Dissertation Repository

Research Questions: The research questions within this thesis aimed to examine the current state of health information exchange (HIE) processes within the Canadian long-term care (LTC) setting and identify opportunities to improve these processes through the proliferation of health information technology (HIT).

Methods: The first study undertook a scoping review following Levac et al’s. approach to the methodology. Next, an interpretive study using semi-structured interviews and Hsieh and Shannon's conventional content analysis methodology was undertaken.

Findings: The scoping review highlighted that effective HIE processes are susceptible to variations in HIT resources, workload, and social and organizational cultures. The findings of …

Assessment Of Executive Function Using A Series Of Operant Conditioning Based Tasks In T1dm Rodents, Kevin T. Murphy

Electronic Thesis and Dissertation Repository

This study examined the impact of Type 1 Diabetes Mellitus (T1DM) on executive function using a series of operant conditioning based tasks in rats. Sprague Dawley rats were randomized to either non-diabetic (n = 12; 6 male) or diabetic (n = 14; 6 male) groups. Diabetes was induced using multiple low-dose streptozotocin injections. All diabetic rodents were insulin-treated using subcutaneous insulin pellet implants. At week 14 of the study, rats were placed on a food restricted diet to induce 5 - 10% weight loss. Rodents were familiarized and tested on a series of tasks that required continuous adjustments to novel …

Examining Public Health Risk Communication Via Social Media By Provincial And Local Health Authorities In Ontario During The Covid-19 Pandemic, Marc Resendes

Electronic Thesis and Dissertation Repository

Risk communication campaigns are essential during public health crises to inform the public about ways to mitigate, alleviate and manage potential risks. The purpose of this study was to describe risk communication on social media by Ontarian health authorities amid COVID-19, in addition to examining the strategies that guided their social media use. This was completed through (a) a narrative review of risk communication literature; (b) a qualitative content analysis of select health authority Twitter messaging following three major COVID-19 milestones; and (c) key informant interviews with those coordinating social media responses to COVID-19. Information giving and news updates were …

Community Health Workers And Trainers Perspectives On Education And Practice: A Qualitative Case Study In The Context Of Maternal And Child Health In Rwanda, Damilola Toki

Electronic Thesis and Dissertation Repository

Achieving global health-care goals hinges on a health workforce that is available, competent, and productive. Chronic health worker shortages impede the abilities of health systems to provide equitable services, especially in low-resource settings.

Global consensus on bridging health workforce gaps calls for alternatives such as using community health workers (CHWs) to achieve health-care aims. CHWs are laypeople who are closely connected with communities and provide frontline health services. Although CHWs are an integral part of workforces in many countries, with potential to inform global health systems, CHW programs continue to operate on the fringe and are fraught with challenges.

This …

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 …

Mechanisms Underlying Enhanced Bone Marrow Adipogenesis In Diabetes, Jina J.Y. Kum

Electronic Thesis and Dissertation Repository

Morbidity and mortality associated with diabetes are due to secondary vascular complications that include both micro- and macro-vascular organ dysfunctions. Our recent studies show that vascular dysfunction and inadequate vessel repair in diabetes may potentially be due to impaired vasculogenesis (de novo vessel formation). Specifically, we have shown that diabetes enhances adipogenesis in the bone marrow and reduces the number of marrow-resident vascular regenerative stem cells. In this study, I have determined the mechanisms of deleterious bone marrow adipogenesis, which may alter the cellular composition of the marrow and lead to the depletion of vascular regenerative stem cells.

My …

Creating Tools To Study The Signaling And Function Of The Adhesion Family Of Gpcrs, Victor M. Mirka

Electronic Thesis and Dissertation Repository

Adhesion GPCRs (aGPCRs) are difficult to study because they are activated by mechanical force. aGPCRs are autoproteolytically cleaved into N-terminal and C-terminal fragments. Mechanical force removes the N-terminal fragment revealing a tethered ligand activating the receptor. Proteinase Activated Receptors (PARs) are N-terminally cleaved by proteinases revealing a tethered ligand activating the receptor. We hypothesized the tethered ligand of aGPCRs could be revealed by replacing the N-terminal fragment with a PAR N-terminus. We fused the PAR2 N-terminus to the C-terminal fragments of four aGPCRs: CD97, EMR2, GPR56, and BAI1. PAR2-aGPCR chimeric receptors dose dependently recruited G-proteins and β-arrestins, supporting our hypothesis. …

Troubling Service User Involvement In Health Professional Education: Toward Epistemic Justice, Stephanie Leblanc-Omstead

Electronic Thesis and Dissertation Repository

It has become increasingly popular in health professional education to solicit the contributions and involvement of people who have firsthand or ‘lived’ experiences of using mental health services – a practice hereafter referred to as service user involvement (SUI). SUI is founded on the premise that service users ought to be involved in the development and evaluation of services and systems they experience, which includes the education of future health professionals. Despite the momentum this practice has gained in a range of international contexts, SUI is often conceptualized, organized, and implemented uncritically, and with tremendous inconsistency across health professional education …