Medicine and Health Sciences Commons^™

Energy Subtraction Methods As An Alternative To Conventional X-Ray Angiography, Christiane S. Burton

Electronic Thesis and Dissertation Repository

Digital subtraction angiography (DSA) is a technique that is widely used to enhance the visibility of small vessels obscured by background structures by subtracting a mask and contrast image. However, DSA is generally unsuccessful for imaging the heart due to the motion that occurs between mask and contrasted images which cause motion artifacts. An alternative approach known as energy subtraction angiography (ESA) exploits the iodine k-edge by acquiring contrast images with a low and high kV in rapid succession to bring the benefits of DSA without motion artifacts. However, it was concluded that image quality for ESA could not compete …

Development Of Anatomical And Functional Magnetic Resonance Imaging Measures Of Alzheimer Disease, Samaneh Kazemifar

Electronic Thesis and Dissertation Repository

Alzheimer disease is considered to be a progressive neurodegenerative condition, clinically characterized by cognitive dysfunction and memory impairments. Incorporating imaging biomarkers in the early diagnosis and monitoring of disease progression is increasingly important in the evaluation of novel treatments. The purpose of the work in this thesis was to develop and evaluate novel structural and functional biomarkers of disease to improve Alzheimer disease diagnosis and treatment monitoring. Our overarching hypothesis is that magnetic resonance imaging methods that sensitively measure brain structure and functional impairment have the potential to identify people with Alzheimer’s disease prior to the onset of cognitive decline. …

Early Experimental Results Of Using A Novel Delivery Carrier, Hyaluronan-Phosphatidylethanolamine (Ha-Pe) Which May Allow Simple Bladder Instillation Of Botulinum Toxin A As Effectively As Direct Detrusor Muscle Injection., Mohamed G. El Shatoury

Electronic Thesis and Dissertation Repository

Intra-detrusor Botulinum Toxin-A (BTX-A) injection is the gold standard treatment for detrusor overactivity in clinical practice when medical treatment fails. Despite satisfactory results of BTX-A injection, the endoscopic procedure still has risks of anaesthetic and operative complications. Several studies have investigated more simple ways to deliver BTX-A to the detrusor muscle but with limited success. In our study, we assessed the evidence of BTX-A delivery using a newly modulated hyaluronan-phosphatidylethanolamine (HA-PE) carrier in a rat model through BTX-A-HA-PE bladder instillations. We used histological evidence of SNAP-25 protein cleavage and detection of Alexa FluorÒ594-labelled BTX-A as a proof of physical BTX-A …

Neurosurgical Ultrasound Pose Estimation Using Image-Based Registration And Sensor Fusion - A Feasibility Study, Utsav Pardasani

Electronic Thesis and Dissertation Repository

Modern neurosurgical procedures often rely on computer-assisted real-time guidance using multiple medical imaging modalities. State-of-the-art commercial products enable the fusion of pre-operative with intra-operative images (e.g., magnetic resonance [MR] with ultrasound [US] images), as well as the on-screen visualization of procedures in progress. In so doing, US images can be employed as a template to which pre-operative images can be registered, to correct for anatomical changes, to provide live-image feedback, and consequently to improve confidence when making resection margin decisions near eloquent regions during tumour surgery.

In spite of the potential for tracked ultrasound to improve many neurosurgical procedures, it …

Cost-Effectiveness Of Selective Laser Trabeculoplasty (Slt) Versus Argon Laser Trabeculoplasty (Alt) In Uncontrolled Open Angle Glaucoma Patients Having At Least One Full Previous Slt: An Economic Evaluation Alongside An Ongoing Randomized Controlled Clinical Trial, Muhammad Rakibuz-Zaman

Electronic Thesis and Dissertation Repository

Background and objective: ALT and SLT are both safe and effective for glaucoma treatment. We performed a cost-effectiveness analysis (CEA) of SLT versus ALT for a six-month follow-up period in uncontrolled open angle glaucoma patients having at least one full previous SLT from an ongoing RCT. Methods: Trial based treatment costing and IOP reduction at 6-month follow-up from baseline for both intervention arms were calculated. A decision tree model was developed considering possible clinical pathways of patients undergoing repeat laser trabeculoplasty. CEA among ALT and SLT was done, and ICERs were calculated from both societal and ministry perspective. One way …

Identification Of A Nuclear Localization Signal (Nls) Within The Pleckstrin Homology (Ph) Domain Of Rho Guanine Nucleotide Exchange Factor (Rgnef), Michael V. Tavolieri

Electronic Thesis and Dissertation Repository

Rho Guanine Nucleotide Exchange factor (RGNEF) is a 180 kDa protein which forms pathological neuronal cytoplasmic inclusions in degenerating spinal motor neurons in amyotrophic lateral sclerosis (ALS) and for which the gene (ARHGEF28) is mutated in a subset of cases. Despite having previously been shown to localize to the nucleus and to undergo a nuclear cytosolic shift in response to cellular injury, the mechanism of its nuclear import has yet to be elucidated. Here we use site-directed mutagenesis with a combination of subcellular fractionation and confocal microscopy to identify a functional nuclear localization signal (NLS) within the Pleckstrin …

A Longitudinal Study To Investigate Changes In Functional Ability And Concerns In Head Neck Cancer Patients Undergoing Neck Dissection, Mariya Ehsan

Electronic Thesis and Dissertation Repository

Introduction:

The study investigated changes of shoulder/neck range of motion (ROM), shoulder strength, patient concerns and quality of life at pre-surgery and 1 month following neck dissection surgery.

Method:

Participants were 30 head and neck cancer patients selected for unilateral neck dissection. Shoulder/neck ROM and shoulder strength were measured at pre-surgery and 1 month post-surgery. The Patient Concerns Inventory-Level of Importance, University of Washington Quality of Life, Shoulder Pain and Disability Index and Neck Dissection Impairment Index were completed at the same time periods.

Result:

A significant drop in ROM and strength were found after surgery. Patients’ concerns changed over …

Investigating The Relationship Between Vascular Health, Gait, And Cognition In Community-Dwelling Older Adults Without Dementia, Michael A. Gregory

Electronic Thesis and Dissertation Repository

Cardiovascular disease (CVD) risk factors contribute to neuropathological changes within regions of the brain that are involved with both cognitive and motor control processes, and have been identified as potentially modifiable dementia and gait dysfunction risk factors. Exercise training is a corner-stone treatment for vascular risk factor control, and evidence suggests that physical and cognitive training can benefit cognition and gait; however, the exercise training modality that can provide the greatest cognitive benefit remains elusive. Therefore, the purpose of this thesis was three-fold: (i) to determine whether CVD risk factors and gait were associated with cognitive functioning, (ii) to determine …

The Biophysical Alterations To Pulmonary Surfactant During Lung Injury, Scott D. Milos

Electronic Thesis and Dissertation Repository

Pulmonary surfactant is a lipoprotein mixture responsible for reducing surface tension of the lung. In this thesis, we investigate the impact of lung injury on surfactant composition and function, with a specific focus on cholesterol content. First, the impact of a high cholesterol diet on surfactant function was assessed in three models of lung injury. It was hypothesized that serum hypercholesterolemia would increase host susceptibility to surfactant functional impairments. Secondly, the impact of injurious ventilation on intracellular surfactant within the lung was investigated. It was hypothesized injurious ventilation would produce alterations to lamellar body surfactant. Overall, the data suggest that …

Maternal Nutrient Restriction With Fetal Growth Restriction In Guinea Pigs Impacts Brain Development And Neuroimaging Correlates In Neonatal Offspring, Catherine Nevin

Electronic Thesis and Dissertation Repository

Aberrant brain development in utero accompanied by fetal growth restriction (FGR) increases the risk of neurodevelopmental disorders in later life. However there are limited non-invasive biomarkers in the brain for the early identification of said neurodevelopmental disorders in an animal model of FGR. Guinea pig sows were fed either ad libitum (Control) or 70% of the control diet pre-pregnancy, increasing to 90% at mid-pregnancy (MNR) creating appropriately grown (AGA) Control and FGR-MNR neonates, respectively. Three to four weeks corrected post-natal age, neonates were imaged using magnetic resonance imaging (MRI) and spectroscopy (MRS) techniques, and were killed 48-72 hours later for …

The Lived Palliative Care Experiences Of Community-Dwelling Older Adults With Dementia In South Western Ontario, Kristina M. Kokorelias

Electronic Thesis and Dissertation Repository

Palliative care is often suggested for individuals with dementia, yet there remains great uncertainty surrounding best delivery of care to individuals wishing to die at home. The aim of this phenomenological study was to understand the experiences of both individuals with dementia who receive palliative care in the community, and their informal family caregivers. Hermeneutic thematic analysis of semi-structured interviews from ten participant dyads revealed key themes. The themes for older adults with dementia were: belonging at home and acceptance of terminal illness; the themes for informal caregivers were: impact of dementia, double strain and home as a source of …

The Long Non-Coding Rna Malat1 Regulates Inflammatory Cytokine Production In Chronic Diabetic Complications, Andrew D. Gordon

Electronic Thesis and Dissertation Repository

We examined the role of MALAT1, a highly conserved nuclear lncRNA, in chronic diabetic complications affecting the heart and kidneys, specifically with respect to inflammatory cytokine production. Endothelial cells, exposed to various glucose levels, and MALAT1 knockout mice and controls, with or without streptozotocin-induced diabetes were examined. Endothelial cells cultured with high glucose, and renal and cardiac tissue from diabetic mice showed increased inflammatory cytokine (eg. IL-6, IL1β, TNFα) production along with transient MALAT1 upregulation. This was confirmed by both transcript and protein analyses, and such changes were prevented in the MALAT1 knockout diabetic animals. In the malat1 knockout animals, …

The Effect Of A Square-Stepping Exercise Intervention On Heart Rate Variability In Older Individuals With Type 2 Diabetes And Subjective Cognitive Complaints, Claire E. Riley

Electronic Thesis and Dissertation Repository

Aging is associated with increased onset of diseases such as type 2 diabetes (T2D) and cognitive impairment. Heart rate variability (HRV), a measure of autonomic function, is reduced in T2D and may have the potential to indicate cognitive decline in this population. Square-stepping exercise (SSE) is a novel cognitive exercise recently implemented in cognitive research, which may have the potential to improve global cognitive function in T2D individuals. Participants with T2D (N=25, aged ≥ 50y) and self-reported cognitive complaints were randomized into either an SSE intervention or a wait-list (WL) control group for 24-weeks. HRV parameters (time and frequency domain) …

Exploring The Self-Regulatory Behaviors Of Elementary Students With Hearing Loss In Inclusive Classrooms, Kendra Di Bacco

Electronic Thesis and Dissertation Repository

An exploratory, mixed-method and multi-level research design was employed to examine relationships among students’ hearing loss, academic achievement and self-regulation (SR), classroom background noise levels, teachers’ perceptions of inclusion of students who are hard of hearing (HH) and features of classroom instruction that support SR. Data consisted of 10 elementary teachers’ perceptions of the inclusion, and ratings of 131 students’, of whom 8 were hard of hearing, SR and academic achievement scores. Classroom observations were conducted to obtain background noise levels and to examine whether and how teachers implement the features of classroom contexts to support SR within their classroom. …

Longitudinal Evaluation Of Patient Concerns After Surgery For Head And Neck Cancer, Isabel Wozniczka

Electronic Thesis and Dissertation Repository

The primary purpose of this study was to investigate and describe the longitudinal effects of shoulder and neck mobility, strength, and quality of life (QOL) following neck dissection (ND) surgery and identify the concerns of head and neck cancer (HNC) patients. ND is one of the standard procedures for treating HNC, which results in many complications and dysfunctions that can have an effect on a patient’s QOL.

The study had 27 eligible HNC participants who underwent ND, of which eight participated in the shoulder range of motion (ROM) and strength and 12 participated in the QOL patient-reported outcomes analysis. The …

Sample Size Formulas For Estimating Intraclass Correlation Coefficients In Reliability Studies With Binary Outcomes, Mengxiao Xu

Electronic Thesis and Dissertation Repository

Introduction: Measurement errors can seriously affect quality of clinical practice and medical research. It is therefore important to assess such errors by conduct- ing studies to estimate a coefficients reliability and assessing its precision. The intraclass correlation coefficient (ICC), defined on a model that an observation is a sum of information and random error, has been widely used to quantify reliability for continuous measurements. Sample formulas have been derived for explicitly incorporation of a prespecified probability of achieving the prespecified precision, i.e., the width or lower limit of a confidence interval for ICC. Although the concept of ICC is applicable …

The Auditory Brainstem Response And Envelope Following Response: Investigating Within-Subject Variation To Stimulus Polarity, Rebekah Taggart

Electronic Thesis and Dissertation Repository

Though the envelope following response (EFR) has potential to become an effective tool for hearing aid validation, studies have observed a considerable degree of within-subject variation with stimulus polarity that could affect its clinical usefulness. This study investigated whether a relationship exists between the polarity-sensitive variation observed in EFR amplitude and that observed in the latencies of a related neural response, the auditory brainstem response (ABR). Low frequency masked clicks and the dual-f₀ stimulus /susaʃi/ were used to evoke alternating polarity ABRs and EFRs, respectively, in 31 normal hearing adults. Maximum and median differences between polarity conditions were calculated. …

The Neuroprotective Effects Of Endurance Training On The Aging Brain, Katelyn Norton

Electronic Thesis and Dissertation Repository

Dysregulation of autonomic control often develops with advancing age, favoring a chronic state of heightened sympathetic outflow with parasympathetic withdrawal. However, the mechanisms of this age-related autonomic impairment are not known and may relate to alterations in brain structure (e.g. cortical atrophy) and/or altered neural function, particularly in regions related to the cortical autonomic network, namely, the medial prefrontal cortex (MPFC), insula cortex (IC), and hippocampus (HC). Exercise exerts beneficial effects on brain structure and, in the case of cognition, neurologic function; however, how exercise affects regions of the brain related to autonomic function are not known. This thesis tested …

Evaluation Of Sexual Orientation Items In Population Health Surveys Among Canadians: A Mixed Methods Approach, Christoffer Dharma

Electronic Thesis and Dissertation Repository

A single item sexual orientation question has been asked in Statistics Canada health surveys to identify health inequalities in Canada. Using a mixed methods study with convenience sample of Canadians, we evaluated this question in comparison to a set of US questions that includes domains of sexual identity, behaviour and attraction. The single item question had an 85.8% sensitivity and 100% specificity in capturing sexual minorities from the broadest definition (n = 311). Chance-corrected agreements with sexual identity, 12 months and life time sexual behaviour were 0.89, 0.39 and 0.48 respectively. Both trans and cisgender people revealed that there were …

An Investigation On The Value Of Integrating Mental Health Supports In Education To Build Capacity For Change, Erin Keith

Electronic Thesis and Dissertation Repository

Current statistics in Ontario show that one in five students suffer from mental health issues (Canada, 2012). Mental health disorders cause significant distress, impairing students’ functioning at school, at home, and in the community (Children’s Mental Health Ontario, 2014). Research has shown that prevention and early intervention strategies targeting students at risk for mental health challenges are beneficial, cost-effective, and reduce the need for more costly, intensive interventions. (Ontario Ministry of Education, 2013). In response to recent Ontario Ministry mental health initiatives (Ontario Ministry of Education, 2006; 2011; 2013), the Peel District School Board, in Ontario, Canada, launched an interprofessional, …

Understanding Views Of Evidence In Public Health Practice And Decision Making In Ontario, Sara Masood

Electronic Thesis and Dissertation Repository

Background: Perceptions of evidence by public health managers, practitioners and policy makers is one of the key determinants of evidence uptake. Therefore, understanding views of evidence in both practice and policy decision making is important to bridge the evidence-practice and policy gap in public health. Objectives & Methods: Two studies are presented in this thesis. The first is a systematic review synthesizing studies exploring the use of research evidence in public health decision making between 2010-2016. The second study is a qualitative descriptive study examining understandings about evidence in Ontario public health units by comparing perspectives from managers and frontline …

The Role Of Postural Stability And Other Factors In Distal Radius Fracture, Sheena Saju Philip

Electronic Thesis and Dissertation Repository

The objective of the thesis was to describe the factors leading to falls in distal radius fracture (DRF) events, explore patient perceived risk of falls, and postural stability. A mixed method study described the type of fall in DRF patients (n= 1454) and patient perceived contributing factors (n=29). A prospective cohort study examined the postural stability and related fall risk of DRF participants (n=137) in Biodex Balance System (BBS) and compared to normative values. Environmental factors were a major contributor to DRF events. Older adults (44 to 65 years) had the highest rate of DRF (female: male ratio of 2:1). …

Drop Vertical Jump Landing Mechanics Following Anterior Cruciate Ligament Reconstruction With And Without Lateral Extra-Articular Tenodesis, Michal Daniluk

Electronic Thesis and Dissertation Repository

The use of combined anterior cruciate ligament (ACL) plus lateral extra-articular tenodesis (LET) reconstruction has shown promising results during clinical testing, however, no studies have examined its effectiveness during a dynamic functional task. We used the drop vertical jump (DVJ) to compare in vivo biomechanics of ACL reconstructed patients with and without LET.

Our primary outcome was peak knee abduction moment during stance phase. Secondary kinetic and kinematic outcomes included peak initial contact and stance values for knee abduction angle, knee flexion moment and angle, knee internal rotation moment and angle, and vertical ground reaction force. We also assessed fear …

Reliability And Validity Of The Star Excursion Balance Test For Patients With Chronic Patellar Instability, Andrew D. Firth

Electronic Thesis and Dissertation Repository

The Star Excursion Balance Test (SEBT) is an eight-direction, maximal-reach balance test whose measurement properties are unknown in participants with chronic patellar instability. We designed an observational study with repeated measures to evaluate the test-retest reliability, cross-sectional and longitudinal construct validity, sensitivity to change and responsiveness of the SEBT in this population. Fifteen patients completed the SEBT and reported outcomes at baseline and two weeks and four patients completed testing three months later at the Fowler Kennedy Sports Medicine Clinic.

Intra-class correlation coefficients (ICC) for the SEBT were fair to good, ranging from 0.66-0.84. The SEBT demonstrates good cross-sectional construct …

Effect Of Modified Corn Starch Ingestion On Soccer Skills And Physical/Cognitive Performance During A Simulated Soccer Game, Manuel D. Quinones

Electronic Thesis and Dissertation Repository

Abstract

Generation UCAN® (UCAN), which contains heat treated non Genetically Modified Organism (GMO) corn starch, has the potential to enhance endurance exercise performance via altering substrate use; however, whether its effects are similar during high intensity, intermittent exercise, like that performed in soccer is unknown. Therefore, the purpose of this study was to assess the effects of UCAN on physical, skill and cognitive performance during and following a simulated soccer game. Eleven trained male soccer players completed a 60-min soccer simulated game on a treadmill, under two experimental conditions: UCAN and an isoenergetic carbohydrate (CHO) placebo. There were no significant …

Expression Of Kallikrein-Related Peptidases (Klks) In Adenoid Cystic Carcinoma, Zachary R. Kerr

Electronic Thesis and Dissertation Repository

Adenoid cystic carcinoma (ACC) of salivary glands is a malignancy known for its slow growth pattern, but poor long-term survival despite aggressive treatment. This highlights the need for an improved approach to its management.

It has been suggested that kallikrein-related peptidases (KLKs), a group of 15 serine proteases, may serve as biomarkers for salivary gland tumors. KLKs are involved in numerous biological processes and have been linked to several cancers.

This study evaluated KLK gene expression in ACC and normal salivary gland tissue (NSGT). Total RNA was isolated from 40 formalin-fixed, paraffin-embedded samples, which included 25 ACCs and 15 NSGTs. …

Disability And Return To Work Following Musculoskeletal Injury, Qiyun Shi

Electronic Thesis and Dissertation Repository

Musculoskeletal disorders (MSDs) are injuries, damage or disorders affecting the musculoskeletal system including muscles, ligaments, nerves, tendons, bones or cartilage etc. MSDs are highly prevalent and associated with sickness absence, reduced work efficiency, job changes and earlier retirement.. They also affect daily activity and social functioning. Although many MSDs are accompanied by minor symptoms and settled spontaneously, approximately 10% of the workforce with MSDs have difficulty resuming their original work or exit the workforce permanently. Return to work after MSDs is complex, and is influenced by many factors including physical, psychological, economic and social factors.

Although there are extensive studies …

Constraining Kinematics During Single-Leg Squats And Step-Ups Can Reduce Quadratus Lumborum Activation And Facilitate Gluteal Activation, Shaylyn Kowalchuk

Electronic Thesis and Dissertation Repository

Increased quadratus lumborum activation and decreased gluteal activation may lead to lateral pelvic drop and increased hip adduction and internal rotation during single-leg exercises. These activation patterns and motions are associated with low back pain or lower extremity injuries. The purpose of this study was to evaluate if mechanically restricting hip adduction and internal rotation of the femur affected muscle activation. Twenty female track and field athletes performed single-leg squats and step-ups, and the quadratus lumborum, gluteus medius and maximus muscles activations were measured with surface electromyography. This study tested the hypothesis that mechanically restricted exercises would decrease quadratus lumborum …

An Evaluation Of The Effectiveness Of A Simulated Classroom-Based Intervention On Concussion Rehabilitation Among Individuals With Persistent Post-Concussion Symptoms, Bedoor Alqenai

Electronic Thesis and Dissertation Repository

Although recent clinical and scientific effort has focused on the development of guidelines for post-concussion return to play/work/learn, there is still relatively little literature that addresses specific treatment methods by which this can be accomplished. Accordingly, this study investigated the effect of a 7-week simulated classroom-based intervention on the self-reporting of symptom scores among 71 individuals with persistent concussion symptoms (26 men and 45 women). All participants were provided with novel strategies for reading, writing, study skills, social communication and technology use. Self-assessment of symptoms were obtained weekly, both before and after each session of the treatment program, in an …

A Randomized Controlled Trial To Establish Realistic Patient Expectations Following Total Knee Replacement Surgery, Sharon E. Culliton

Electronic Thesis and Dissertation Repository

Objectives: To evaluate whether e-learning videos can affect whether patients felt their expectations were met and were satisfied with surgery 1 year following primary total knee replacement (TKR) (Chapter 3). In Chapter 4, we described characteristics of users and utilization patterns of the e-learning tool. In Chapter 5, we evaluated the internal consistency and construct validity of the new Knee Society Knee Scoring System (KSS) in a sample of TKR patients.

Methods: We recruited consecutive patients with osteoarthritis from the London Health Sciences Centre, Ontario, Canada (Chapter 3). We randomized patients with osteoarthritis to either control (n=207) they received our …