Medicine and Health Sciences Commons^™

Characterizing The Function Of B Cells That Accumulate In The Inflamed Central Nervous System In Anti-Myelin Autoimmunity, Lika Chowdhury

Electronic Thesis and Dissertation Repository

While the role of autoimmune T cells has been extensively studied in anti-myelin

autoimmunity, little is known about the function of B cells in multiple sclerosis (MS), a chronic inflammatory disease of the central nervous system (CNS). B cells form clusters with T cells in the meninges directly adjacent to demyelinating lesions. Previous studies have shown that disease progression is dependent on the depletion of specific populations of B cells, but it is not clear which contributes to pathology or how. The purpose of this thesis is to characterize the population of meningeal B cells to determine how they differ …

Rapid Rhino Vs. Merocel: A Retrospective Analysis Of Patients With Anterior Epistaxis Visiting Emergency Rooms In London, Ontario, Dhatri Shukla

Electronic Thesis and Dissertation Repository

When patients present to an emergency room (ER) with a nosebleed, one technique that physicians employ is the application of nasal packing. Merocel is a common nasal pack utilized in ER because of their low cost. Rapid Rhino is a nasal packing that is more comfortable for patients but is more costly than Merocel. Costing for epistaxis treatment is more than initial treatment costs and needs to consider rebleed rates. Using a retrospective cohort study design with covariates adjusted by propensity scores, we compared the costs associated with Merocel, and Rapid Rhino from the hospital and provincial healthcare perspectives. Merocel …

S100a7 As A Biomarker For Predicting Transformation In A Potentially Malignant Lesion: Lichen Planus., Jeff J. Lovell

Electronic Thesis and Dissertation Repository

Oral Lichen Planus (OLP) is a potentially malignant disorder that has a malignant transformation rate of approximately 1%. Current management includes incisional biopsy and grading of dysplasia, if present. This may not be a reliable predictive tool for malignant transformation. Tissue biomarkers such as S100A7 may provide a more accurate method of risk determination. The proposed mechanism is an association between S100A7 and the MAPK signalling pathway. Paraffin embedded sections of OLP that progressed and did not progress on serial biopsy were selected. The tissues were stained via S100A7 immunohistochemistry. S100A7 was quantified using an Immunoreactivity score, QuPath and StraticyteÔ. …

Examining The Socio-Economic And Gendered Structure Of Canada's Live-In Caregiver Program: A Qualitative Study Of Filipina Women's Health Experiences, Andrea Bobadilla

Electronic Thesis and Dissertation Repository

The primary aim of this critical ethnographic study was to examine how Filipina women in the Canadian live-in caregiver program (LCP) negotiate their own physical and mental well-being while managing the complex health needs of their clients. Using global care chain and postcolonial theoretical frameworks, I also sought to identify how multi-scalar forces including caregiving and migrant policies in Canada and South East Asia exacerbate pre-existing gendered and labour inequities faced by these women. The distressing impact of this precarious form of employment on family dynamics and relationships among family members in the Philippines was also explored. Data collection took …

Monitoring Intraventricular Hemorrhage In Preterm Infants, Lilian Mn Kebaya

Electronic Thesis and Dissertation Repository

Germinal Matrix-Intraventricular hemorrhage (GMH-IVH) remains a significant cause of adverse neurodevelopmental outcomes in preterm infants. Current management options for GMH-IVH rely on serial 2-dimensional cranial ultrasound (2D cUS) ventricular measurements and clinical signs. A need exists for reliable biomarkers to aid in the early detection of posthemorrhagic ventricular dilatation (PHVD) and cerebral palsy (CP). We incorporated 3-dimensional cranial US (3D cUS) and functional infrared spectroscopy (fNIRS) to monitor ventricle volumes (VV) and spontaneous functional connectivity (sFC) in preterm infants with GMH-IVH. Infants with severe GMH-IVH who underwent cerebrospinal fluid diversion showed larger VV, which correlated with decreased sFC. Our findings …

Fertility Preservation Discussions With Transgender People In Canada Prior To Beginning Medical Gender Affirmation, Emily K. Sanders

Electronic Thesis and Dissertation Repository

Background. Prevalence of fertility preservation discussions and procedures, participant characteristics associated with discussions, and prevalence of desire to parent are described.

Methods. Describes, for a clinical sample of < 16-year-olds: medical chart-recorded discussion and procedure prevalence, and desire to parent longitudinally. Describes self-reported discussion prevalence for a community sample of 14- to 39-year-olds. Bivariate and multivariable modified Poisson analyses were conducted for this sample.

Results. Discussion prevalence was confirmed for approximately 80% of the clinical sample, with approximately 20% unconfirmed. Self-reported discussion prevalence was 45% in the community sample. Non-binary gender with female sex at birth, greater family religiosity, and diagnosed mental health condition excluding depression or anxiety were crudely associated with less discussions. Multivariable analyses revealed no statistically significant predictors. Desire to parent was fairly consistent over time.

Conclusion. Discussions should be standard practice for …

Association Of Socioeconomic, Racial, And Regional Factors With In-Hospital Management And Outcomes Of Acute Myocardial Infarction Patients In The United States: National Analyses Of 2.8 Million Admissions, Olivia Haldenby

Electronic Thesis and Dissertation Repository

Social determinants of health contribute to variations in clinical outcomes among acute myocardial infarction (AMI) patients. Using the National Inpatient Sample, we conducted retrospective cohort analyses to evaluate the association of income, race, and geography with in-hospital mortality and revascularization procedures among AMI admissions in the United States from 2015 to 2019. Multilevel logistic regression models were used while accounting for hospital clustering and relevant predictors. A sequential model-building approach produced model 1 (unadjusted patient-level exposures), model 2 (lifestyle factors), model 3 (clinical characteristics), and model 4 (fully adjusted hospital-level factors). We identified 2,798,225 AMI hospitalizations (≥18 years) with 1,567,575 …

Secretion Of Salivary Proteins And Their Interactions, Karla Tonelli Bicalho Crosara

Electronic Thesis and Dissertation Repository

Saliva’s clinical application for disease diagnosis and monitoring is limited by incomplete knowledge of salivary protein interactions, the effect of stimulation on the salivary proteome, and if these factors impact protein identification. This thesis expands knowledge of the salivary interactome and effects of stimulation intensity and duration on parotid saliva’s proteome. First, previous in vitro studies identified 43 proteins in the histatin 1-protein network and demonstrated histatin 1’s increased stability in whole saliva when interacting with amylase. We hypothesized that protein-protein-interaction databases could enlarge the histatin 1-protein network. A comprehensive histatin 1-protein network was created using STRING database, merging previous …

Development Of An On-Call Assessment Tool For Competency-Based Surgical Training, Eric C. Mitchell

Electronic Thesis and Dissertation Repository

Introduction: A central tenet of competency-based medical education is formative assessment of trainees. There are no assessments examining resident competence on-call, despite this being a significant component of resident training and characterized by less supervision compared to daytime.

Methods: A national survey was conducted to evaluate the state of assessment in Canadian Plastic and Reconstructive Surgery programs. An on-call assessment tool was developed based on a consensus group and was piloted over six months. Validity of the tool was examined through qualitative and quantitative methods.

Results: There were 63 tools completed across ten residents and seven staff physicians. Tool reliability …

Social Determinants Of Access To Primary Care In Canada, Feben W. Alemu

Electronic Thesis and Dissertation Repository

Despite the promise of universal care, many Canadians report having unmet healthcare needs. We conducted two studies: (1) a systematic review of studies on social determinants of health (SDH) and unmet need; and (2) a secondary analysis using the Canadian Longitudinal Study on Aging (CLSA) to investigate the association of SDH and (2a) self-reported unmet need and (2b) having a family physician. The review (n=40) found a positive association between unmet need and lower income, mental health and chronic conditions, and negative association with older age, better perceived health and having a family physician. The CLSA analysis found the odds …

Simulated And Experimental Approaches To The Development Of Novel Test Phantoms For Radiofrequency Heating Of Implanted Medical Devices, Amgad M. Louka

Electronic Thesis and Dissertation Repository

Magnetic resonance imaging (MRI) has cemented itself as the gold standard for imaging of soft tissues and is only increasing in popularity. Given the rising number of MRI scanners and medical device being implanted into patients, it is becoming increasingly likely that patients undergoing MRI will have an implanted medical device (IMD). The presence of an elongated metallic IMD inside a scanner could result in dangerous interactions with the radiofrequency fields during MRI, thus some of these IMDs preclude the patients from being scanned.

Orthopedic devices typically fall into this category due to their high potential for RF induced heating, …

Indocyanine Green Angiography In Pediatric Colorectal Surgery, Robin B. Wigen

Electronic Thesis and Dissertation Repository

Hirschsprung Disease (HD) and Anorectal Malformations (ARM) are congenital colorectal conditions that necessitate surgical correction via bowel resection with the creation of an anastomosis. Surgical complications, thought to be in part due to malperfusion of the bowel anastomosis, are frequent, as revealed by the retrospective review enclosed. Indocyanine Green Angiography (ICGA) is a process in which water-soluble dye (ICG) is used to assess perfusion of tissue, and it has been employed with success in adult populations to reduce rates of anastomotic leak during colorectal surgery. The systematic review conducted within confirms that this tool has not been extensively studied in …

Noninvasive Quantification Of Tissue Sodium Concentration In The Kidney Disease Spectrum Using 23na Magnetic Resonance Imaging, Fabio R. Salerno

Electronic Thesis and Dissertation Repository

Chronic kidney disease (CKD), especially when requiring kidney replacement therapy (hemodialysis (HD) and peritoneal dialysis (PD)), is associated with extracellular water expansion with increased total body sodium. Sodium can also be accumulated in tissues independently of extracellular water. Sodium-23 magnetic resonance imaging (²³Na MRI) can quantify the concentration of sodium nuclei in tissues. Applied to the human leg, quantification of tissue sodium concentrations mainly at the skin and muscle level is possible. We hypothesized that increased tissue sodium concentrations exert toxic effects in CKD and dialysis. We aimed to (1) compare tissue sodium concentrations in adults, children and …

Severe Lower Extremity Trauma In Ontario: A Linked Population-Based Analysis, Stephanie M. Kim

Electronic Thesis and Dissertation Repository

Open tibia fractures (OTF) are a management challenge. Admission to a trauma center (TC) and a coordinated approach to bony fixation and soft-tissue reconstruction (STR) have been shown to improve outcomes. The objective of this study was to describe patients who had OTF in Ontario and analyze their outcomes. Linked population data pertaining to patients who had OTF between the years 2009-2020 were examined. Demographic information, admission location, and management course were collected. 4240 patients were found. The mean age was 47, and majority were males. Patients admitted to TC had greater proportion of having Injury Severity Score >15, and …

Data-Driven Neuroanatomical Subtypes In Various Stages Of Schizophrenia: Linking Cortical Thickness, Glutamate, And Language Functioning, Liangbing Liang

Electronic Thesis and Dissertation Repository

The considerable variation in the spatial distribution of cortical thickness changes has been used to parse heterogeneity in schizophrenia. We aimed to recover a ‘cortical impoverishment’ subgroup with widespread cortical thinning. We applied hierarchical cluster analysis to cortical thickness data of three datasets in different stages of psychosis and studied the cognitive, functional, neurochemical, language and symptom profiles of the observed subgroups. Our consensus-based clustering procedure consistently produced a subgroup characterized by significantly lower cortical thickness. This ‘cortical impoverishment’ subgroup was associated with a higher symptom burden in a clinically stable sample and higher glutamate levels with language impairments in …

Comparison Of Hip Navigation System Accuracy In Direct Anterior Approach, Jeremy Loh

Electronic Thesis and Dissertation Repository

Introduction

Malposition of the acetabular component has been thought to have an influence on increasing increase the risk instability, impingement, and ultimately revision surgery. Hip navigation technology has been developed to provide the surgeon with real time intraoperative metrics to make critical decisions in implant placement. The goal of this study was to compare the accuracy of acetabular component positioning in direct anterior approach hip replacements using conventional fluoroscopy only technique, fluoroscopic image dependent navigation, and imageless navigation.

Methods

A retrospective data collection and prospective analysis was conducted for this study. After sample size calculations, fifty patients were collected for …

Postexercise Executive Function Benefits And Cerebral Blood Flow: In The Lab And At Home, Benjamin Tari

Electronic Thesis and Dissertation Repository

A single bout of aerobic exercise improves executive function; however, the mechanism, or mechanisms, supporting this improvement remain unclear. One candidate mechanism is an exercise-mediated increase in cerebral blood flow (CBF) that enhances the efficiency of executive-related frontoparietal networks. To evaluate the link between exercise, CBF and executive function, three separate experiments were conducted. In the first study, separate 10-min sessions of moderate-to-heavy-intensity aerobic exercise, and a hypercapnic environment (i.e., 5% CO₂) were implemented. The hypercapnic condition was included because it increases CBF independent of the metabolic demands of exercise. The second study investigated whether exercise intensity-specific changes …

Encouraging Movement Opportunities Through Theory-Informed Video Education In Undergraduate Students: The Move Study, Carmen T. Labadie

Electronic Thesis and Dissertation Repository

This mixed methods randomized control trial explored the impact of a tailored, Health Belief and Transtheoretical Model informed educational video on undergraduate students’: (1) motivational readiness, self-efficacy, and decisional balance about changing sedentary behaviour; (2) levels of sedentary time; and (3) perceptions of sedentary behaviour over time and when compared to a control condition. Students (N = 160) were randomly assigned to the intervention or control group. Participants completed: two previously validated questionnaires at baseline, immediate post-intervention, and one-month follow-up; and open-ended questions at post-intervention (intervention group only). Linear mixed models and inductive content analysis were used. Significant differences …

A Long-Term Follow-Up Of The Stability Study: Multicenter Rct Comparing Anterior Cruciate Ligament Reconstruction With And Without Lateral Extra-Articular Tenodesis In Individuals At High Risk Of Graft Failure, Katelyn M. Inch

Electronic Thesis and Dissertation Repository

One hundred and ninety-six patients at the Fowler Kennedy Sport Medicine Clinic (FKSMC) undergoing anterior cruciate ligament (ACL) reconstruction (ACLR) were randomized as part of the multi-center STABILITY study to receive either an isolated ACLR or ACLR with a lateral extra-articular tenodesis (LET). The STABILITY study followed these patients up to two years postoperative, and a long-term follow-up protocol was initiated afterwards. Eighty-two patients from this center were seen at three, five and seven years postoperative as part of a long-term follow-up. Our primary outcome was a composite outcome of instability and graft failure. Secondary outcomes included patient-reported outcome measures …

The Effect Of Oral And Topical Antibiotics On Foreskin Inflammation And Hiv Target Cells In Ugandan Men., Zhongtian (Eric) Shao

Electronic Thesis and Dissertation Repository

Penile circumcision reduces HIV susceptibility by up to 60% in men; however, many men prefer to remain uncircumcised for personal or cultural reasons. Penile circumcision protects against HIV by reducing anaerobic bacteria on the penis. Penile anaerobes cause local inflammation and the recruitment of HIV-susceptible CD4+CCR5+ cells, increasing the likelihood that exposure to HIV during intercourse results in infection. To determine if a non-surgical intervention can reduce penile anaerobes and HIV target cells, we randomized men to antimicrobial treatment prior to circumcision. To be able to quantify the effect of antimicrobials, we developed a novel deep-learning algorithm to quantify HIV …

Maid (Medical Assistance In Dying) And Meaning: An Exploration Of The Experience And Ability To Make Meaning Through Involvement In A Maid-Specific Bereavement Group, The Synergistic Potential Of Covid-19 And Maid, And The Impact Of Healthcare Providers Relationships From The Perspective Of Relational Ethics On The Legacy Of Maid-Involved Families Into Their Bereavement, Allyson Van Kessel

Electronic Thesis and Dissertation Repository

MAiD became legally accessible to Canadians with a grievous and irremediable illness in June of 2016. As I write in 2023, MAiD has been expanded to include patients who do not have a foreseeable death, with anticipated inclusion of those with mental illness as a sole underlying medical condition (MI-SUMC) in 2024. As MAiD now accounts for over 3% of all deaths annually in Canada, there is a growing impetus to explore ways by which MAiD practice can be improved and care can be extended to the family members following the death of a patient.

A hospital in southwestern Ontario …

A Framework For Stable Robot-Environment Interaction Based On The Generalized Scattering Transformation, Kanstantsin Pachkouski

Electronic Thesis and Dissertation Repository

This thesis deals with development and experimental evaluation of control algorithms for stabilization of robot-environment interaction based on the conic systems formalism and scattering transformation techniques. A framework for stable robot-environment interaction is presented and evaluated on a real physical system. The proposed algorithm fundamentally generalizes the conventional passivity-based approaches to the coupled stability problem. In particular, it allows for stabilization of not necessarily passive robot-environment interaction. The framework is based on the recently developed non-planar conic systems formalism and generalized scattering-based stabilization methods. A comprehensive theoretical background on the scattering transformation techniques, planar and non-planar conic systems is presented. …

Exploration Of The Pathophysiological Mechanisms Underlying Hemodialysis Associated Cardiac Ischemic Injury, Lisa Yun Jeong Hur

Electronic Thesis and Dissertation Repository

Hemodialysis (HD) provides life-saving treatment in individuals with kidney failure. However, HD is associated with poor quality of life and extremely high mortality rates mainly caused by cardiovascular disease due to heart failure and sudden cardiac death. Standard pharmacological treatment developed within the non-kidney disease community are largely ineffective in HD patients because of the difference in pathophysiology of cardiovascular mortality. HD treatment causes hypotension and recurrent ischemic injury to multiple vascular beds including the heart, leading to heart failure. These injuries can be abrogated by improving the patient’s tolerability of the treatment. To apply interventions that may improve hemodynamic …

Mindfulness With Children And Youth: A Hermeneutic Phenomenological Inquiry Into Paediatric Therapists' Experiences, Kirsten S. Smith

Electronic Thesis and Dissertation Repository

Background: Mindfulness has become popular as a treatment approach for many health conditions and has been taken up by diverse health practitioners in recent years. While research into mindfulness-based interventions is on the rise, much of this research originates in the field of psychology and is aimed toward adult populations. Occupational therapists, including those working with children and youth, have begun to take up mindfulness to support their clients to participate in daily activities, and there is evidence that clinical uptake has outpaced research in this area.

Method: A scoping review was undertaken to understand the breadth of literature regarding …

The Clinical Value Of Oculomotor Assessments Across The Continuum Of Concussion, Dillon Richards

Electronic Thesis and Dissertation Repository

Concussions are complex conditions that are difficult to manage medically. Variations in symptom presentation, intricate neurophysiological processes, and the availability of a variety of possible assessment tools may contribute to this complexity. Clinicians must use a broad approach, employing both subjective symptom assessment and objective assessments to confirm a diagnosis and/or monitor progression and recovery. Oculomotor function after concussion may be an important indicator of injury, given the interconnectedness of oculomotor function, vestibulo-ocular and visual systems, and even cognition. Oculomotor function may be assessed objectively or indirectly using patient-reported symptom checklists as part of subjective assessments. One way of objectively …

Total Hip Arthroplasty In Young Patients, Aaron G. Chen

Electronic Thesis and Dissertation Repository

Total hip arthroplasty (THA) is the gold standard in treatment of hip arthritis yet is often avoided in young patients due to concerns of inferior survivorship. We aim to explore the role of THA in young patients and assess whether these historical concerns are valid in contemporary THA by presenting the results of: (1) a systematic review and meta-analysis of the current literature, (2) a retrospective database review, and (3) a retrospective population-based study. We found excellent long-term survivorship with modern THA in young patients, demonstrating greater than 90% revision-free survival up to 15 years. Factors that may increase risk …

Decompression Vs. Decompression And Fusion In Cauda Equina Syndrome Secondary To Massive Lumbar Disc Herniation, Ruheksh Raj

Electronic Thesis and Dissertation Repository

Posterior spinal surgery through either a decompression or additional fusion procedure is the widely accepted standard of care for patients presenting with cauda equina syndrome (CES) secondary to massive disc herniation. A plethora of literature has been published regarding post- surgical outcome, particularly in regards to improvement of lower sacral nerve symptoms in relation to timing of surgery. There is a paucity of data with regards to long term clinical outcomes in patients between the decompression and decompression and fusion groups. We initially hypothesized was that there would be no longer term clinical differences in outcome between the two groups, …

Internet-Delivered Cognitive Behavioural Therapy For People With Mild Traumatic Brain Injury: A Feasibility Study, Ujjoyinee France Barua

Electronic Thesis and Dissertation Repository

Individuals with mild traumatic brain injury (mTBI) can experience high levels of emotional distress, leading to decreased quality of life and increased health care costs. Bowen's feasibility framework was used to examine the feasibility, acceptability, and limited efficacy of an innovative clinician-guided internet-delivered cognitive behavioural therapy program (ICBT) specialized for people with mTBI to improve their wellbeing. The data illustrated strong adherence and program satisfaction from participants. Likewise, statistically and clinically significant changes in symptoms of unhappiness and anxiety were found, along with improved self-efficacy and quality of life. The findings of this study contribute new knowledge to the emerging …

Predictors And Outcomes Of Patient Stigma Perception Appraisal: Developing And Testing Of A Dynamic Stigma Model Of Mental Illness, Sebastian Kwadwo Gyamfi

Electronic Thesis and Dissertation Repository

Background

The psychosocial perspectives of stigma have been explored over the years. However, research that encompasses the study of stigma as a socio-cultural, religious, and moral phenomenon is lacking. This study aimed to develop and test a Dynamic Stigma Model of Mental illness (DYSMO) among a cohort of Outpatients receiving care in Ghana.

Methods

The study examined hypothesized relationships within a newly developed stigma model using structural equation modeling techniques. A non-probabilistic convenience sampling technique was used to recruit 330 participants at the Out-Patient Department of two psychiatric hospitals in Southern Ghana.

Results

Confirmatory factor analysis produced a final model …

The Lived Experiences Of Pain And Fatigue In Persons Living With Neurological Conditions: A Phenomenological Study, Lauren L. Kane

Electronic Thesis and Dissertation Repository

Purpose: The aim of the study was to understand the experiences and impact of pain and fatigue and to further explore the relationship between participants' descriptions of their lived experiences with these phenomena within and across multiple sclerosis, Parkinson's disease, and cerebral palsy. Methods: Semi-structured interviews were used to interview nine participants about their experiences of living with pain and fatigue in their respective conditions. A new phenomenological approach was adopted, and data was analyzed inductively using interpretive phenomenological analysis. Results: Three final themes including a lack of understanding, negative perceptions of pain and fatigue, and coping strategies used to …