Medicine and Health Sciences Commons^™

Antithrombotic Therapy In Patients Undergoing Coronary Artery Bypass Grafting: A Systematic Review And Network Meta-Analysis, Karla Solo

Electronic Thesis and Dissertation Repository

Comprehensive evidence on the comparative effects of various oral antithrombotic agents on the prevention of saphenous vein graft failure (SVGF) for patients undergoing coronary artery bypass is lacking. A systematic review and frequentist random-effects network meta-analysis of 18 RCTs (n=3,413 patients) comparing the effect of antithrombotic agents on SVGF and clinical outcomes was performed. Based on moderate quality evidence, among the six eligible interventions, dual-antiplatelet therapy with aspirin and clopidogrel was superior to aspirin monotherapy in reducing SVGF (OR: 0.63; 95% CI: 0.41-0.97). No statistical differences were found for major bleeding, mortality, and myocardial infarction between antithrombotic agents, owing to …

Goals Of Family Caregivers Of Persons With Dementia Across The Caregiving Career, Shalane R. Basque

Electronic Thesis and Dissertation Repository

Understanding goals of family caregivers of persons with dementia is critical to provide effective education and support. However, there is little understanding about family caregivers’ goals. This study investigated goals set by family caregivers prior to an education and training program and whether their goals varied across the caregiving career. Phases of the caregiving career were measured by relationship identity; the extent to which participants viewed their relationship in terms of familial and caregiver roles. Conventional content analysis on goals of 30 family caregivers yielded five categories which varied by relationship identity. Enhancing relationships reflected goals for the familial role …

Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed

Electronic Thesis and Dissertation Repository

The fast diminishing of fossil fuels in the near future, as well as the global warming caused by increasing greenhouse gases have motivated the urgent quest to develop advanced materials as cost-effective photoanodes for solar light harvesting and many other photocatalytic applications. Recently, titania nanotube arrays (TNTAs) fabricated by anodization process has attracted great interest due to their excellent properties such as: high surface area, vertically oriented, highly organized, one-dimensional, nanotubular structure, photoactivity, chemical stability and biocompatibility. This unique combination of excellent properties makes TNTAs an excellent photoanode for solar light harvesting. However, the relatively wide band gap energy of …

Carbohydrates And Fungal Toxin Exposure Influence The Vaginal Microbiota, Metabolome, And Reproductive Health Of Women, Stephanie L. Collins

Electronic Thesis and Dissertation Repository

The reproductive health of women is influenced by microorganisms and their metabolites, namely those representing the vaginal microbiota and those producing toxins that are ingested. To manipulate the vaginal microbiota toward a health-associated, Lactobacillusdominant state, an approach adopting prebiotic lactulose was taken. Using batch culture, lactulose supported Lactobacillus maintenance and positively altered metabolites, while not disrupting indigenous L. crispatus epithelial adherence. The vagina also harbours abundant glycogen, but initial assumptions that lactobacilli utilize it were incorrect. I have now shown that glycogen selectively stimulates organisms associated with dysbiosis and L. iners in a self-limiting manner. Other compounds such as environmental …

Prostate Cancer Microparticles In Men Undergoing Radical Prostatectomy, Malcolm James Dewar

Electronic Thesis and Dissertation Repository

Objectives: To determine changes in prostate microparticle (PMP) concentrations in men with prostate cancer (PCa) after digital rectal examination (DRE), after radical prostatectomy (RP), and at follow-up.

Materials and Methods: 22 men were recruited before RP. Four blood specimens were collected – baseline (specimen 1), post-DRE (specimen 2), immediately post-RP (specimen 3), and follow-up (specimen 4). Pre- and post-DRE urine was collected (Specimen A and B respectively). Flow cytometric analysis of biofluids was performed with fluorescent-labeled antibodies against prostate-specific membrane antigen (PSMA) and polysialic acid. Total MP (TMP) and dual positive (PMP) events per µl of plasma or urine were …

Liver X Receptor And Retinoid X Receptor In Cartilage Development And Homeostasis, Man-Ger Sun

Electronic Thesis and Dissertation Repository

Osteoarthritis (OA) is a heterogeneous and multifactorial degenerative disease characterized by cartilage degradation in the joint. Available treatment options target symptoms but do not address the underlying issue of joint tissue degeneration. A better understanding of the molecular mechanisms maintaining cartilage health is essential for developing novel therapeutic strategies. Previous studies have shown the nuclear receptor Liver X Receptor (LXR) to possess protective roles against cartilage breakdown in OA, however the underlying mechanisms behind this process remain unknown. Since LXR regulates transcription by forming obligate heterodimers with another nuclear receptor, the Retinoid X Receptor (RXR), I hypothesized that LXR and …

Effects Of Prenatal Bisphenol A Exposure On Adrenal Gland Development And Steroidogenic Function, Samantha Medwid

Electronic Thesis and Dissertation Repository

Developmental exposure to bisphenol A (BPA), a ubiquitous endocrine disrupting chemical, is associated with organ dysfunction and diseases in adulthood. However, little is known about its effects on the adrenal glands. Therefore, this thesis addresses this important question using both in vivo and in vitro approaches. BPA at environmentally relevant doses was administrated via diet to pregnant mice from embryonic day 7.5 to birth, following which mice were switched to a standard chow. At two months postnatally, adrenal glands and blood samples were collected from adult mouse offspring for structural and functional analysis. I found that: (a) BPA increased adrenal …

Hepcidin-Mediated Iron Regulation In P19 Cells Is Detectable By Mri, Kobra Alizadeh Pourbouyeh

Electronic Thesis and Dissertation Repository

Magnetic resonance imaging (MRI) can be used to track cellular activities in the body using iron-based contrast agents. However, intrinsic cellular iron handling mechanisms may also influence the detection of magnetic resonance (MR) contrast. For instance, inflammation involves downregulation of iron export in macrophages by the hormone hepcidin, due to degradation of the iron export protein, ferroportin (Fpn). We examined the effect of hepcidin on iron regulation and MR transverse relaxation rates in multi-potent P19 cells, which display high iron export activity, similar to macrophages. In response to varying conditions of iron supplementation, our results showed similar Fpn expression in …

Proteomic Characterization Of Human Multipotent Stromal Cells Secreted Proteins With Therapeutic Potential For Β-Cell Regeneration, Miljan Kuljanin

Electronic Thesis and Dissertation Repository

Novel strategies to stimulate the expansion of β-cell mass in situ are warranted for diabetes therapy. Cell-replacement therapies for the treatment of diabetes have become a focal point in recent years. Endogenous regeneration of β-cell mass has been demonstrated using human multipotent stromal cells (hMSC). However, the secretory factors responsible for initiating endogenous regeneration remain unknown. Successful large-scale proteomic applications to address these questions have been limited in part by difficulties in correctly selecting the appropriate methodologies. Thus, the goal of this thesis was a combination of assessing different proteomic workflows to facilitate investigation into hMSC biology, applying these methods …

Crispr Screen For Identification Of Kinases That Mediate Prostate Cancer Cell Invasion, Hamad Aldhafeeri

Electronic Thesis and Dissertation Repository

Metastasis is the primary cause of mortality in cancer patients. Inhibition of proteins that are involved in the regulation of metastasis are expected to suppress metastasis and represent treatment targets. Our focus is on prostate cancer metastasis and we have developed a novel high-throughput means of performing in vitro screens for regulators of prostate cancer metastasis. We propose to use a focused CRISPR library screen that will “knock out” all human kinases to determine which ones are responsible for prostate cancer metastasis. CRISPR is a potent genetic editing tool and was used to silence all kinases in prostate cells (BPH …

Neuronal Correlates For Neuroendocrine Habituation To Repeated Stress, Sara Matovic

Electronic Thesis and Dissertation Repository

One way that the body actively responds to an impending stressor is by increasing systemic glucocorticoids through the activation of the hypothalamic-pituitary-adrenal (HPA) axis. While it is essential for short-term adaptation to stress, the sustained activation of the HPA axis during chronic stress can be detrimental and is linked to stress-related psychiatric conditions such as anxiety and depression. Therefore, it is important that the HPA axis adapts, or habituates, during chronic stress to minimize the negative consequences. Corticotropin releasing hormone (CRH) neurons in the paraventricular nucleus of the hypothalamus (PVN) function to assimilate incoming information from the stress circuitry and …

Coevolving Residues And The Expansion Of Substrate Permissibility In Laglidadg Homing Endonucleases, Thomas A. Mcmurrough

Electronic Thesis and Dissertation Repository

Genome-editing (GE) is a form of genetic engineering that permits the deliberate manipulation of genetic material for the study of biological processes, agricultural and industrial biotechnologies, and developing targeted therapies to cure human disease. While the potential application of GE is wide-ranging, the efficacy of most strategies is dependent upon the ability to accurately introduce a double-stranded break at the genomic location where alterations are desired. LAGLIDADG homing endonucleases (LHEs) are a class of mobile genetic element that recognize and cleave 22-bp sequences of DNA. Given this high degree of specificity, LHEs are powerful GE reagents, …

Navigating Occupation And Identity In Parkinson's Disease: A Qualitative Exploration Of Lived Experience, Sara G. Lutz

Electronic Thesis and Dissertation Repository

Evidence-based practice requires that health care providers interpret the best research evidence in the context of their clinical experience, while at the same time considering client knowledge and experiences. Although health care providers are becoming increasingly skilled at the evaluation of research evidence, client values and self-identified health issues are often neglected within the evidence-based practice process. Ignoring these key aspects of person-centered practice may lead to interventions that fail to target implications of a client’s disease that are important to occupational participation and quality of life. A focus on person-centeredness is particularly important in progressive neurodegenerative disorders such as …

Chronic Disease Risk Prediction Models And Their Impacts On Behavioural And Health Outcomes: A Systematic Review And Meta-Analysis, Patrick Kim

Electronic Thesis and Dissertation Repository

Risk prediction models are tools that predict an individual’s risk of developing a health outcome. They were developed to influence patient management by guiding preventive interventions, with the goal of reducing the incidence of new diseases. Studies examining their impacts are uncommon, and no consensus regarding their effects has been reached. This systematic review sought to determine the impact of risk prediction models for chronic diseases on physician behaviour, patient behaviour, and patient health outcomes. Twenty-two studies were found to be eligible for review. The results demonstrated that: 1) physician behaviour may be positively influenced, though a statistically significant result …

Evaluating Small Airways Disease In Asthma And Copd Using The Forced Oscillation Technique And Magnetic Resonance Imaging, Heather M. Young

Electronic Thesis and Dissertation Repository

Obstructive lung disease, including asthma and chronic obstructive pulmonary disease (COPD), is characterized by heterogeneous ventilation. Unfortunately, the underlying structure-function relationships and the relationships between measurements of heterogeneity and patient quality-of-life in obstructive lung disease are not well understood. Hyperpolarized noble gas MRI is used to visualize and quantify ventilation distribution and the forced oscillation technique (FOT) applies a multi-frequency pressure oscillation at the mouth to measure respiratory impedance to airflow (including resistance and reactance). My objective was to use FOT, ventilation MRI and computational airway tree modeling to better understand ventilation heterogeneity in asthma and COPD. FOT-measured respiratory system …

Intraoperative Photoacoustic Imaging Of Breast Cancer, Ivan Kosik

Electronic Thesis and Dissertation Repository

Breast cancer is one of the most common cancers to affect women, presenting a lifetime risk of 1 in 8. Treatment of stage 1 and 2 cancers usually involves breast conserving surgery (BCS). The goal of BCS is to remove the entire tumour with a surrounding envelope of healthy tissue, referred to as a negative margin. Unfortunately, up to 50% of surgeries fail to remove the whole tumour. To minimize the risk of cancer recurrence, a second surgery, must therefore be performed. Currently, there is no widely accepted intraoperative tool to significantly mitigate this problem. Employed systems are usually based …

A Biomechanical Study Examining The Subacromial Balloon Spacer And Superior Capsular Reconstruction In The Treatment Of Massive, Irreparable Rotator Cuff Tears, Supriya Singh

Electronic Thesis and Dissertation Repository

Rotator cuff tears are common tendon injuries and can be a major source of pain and disability. Massive, irreparable rotator cuff tears are a challenging surgical dilemma as currently there is no gold standard treatment algorithm. Multiple possible treatment options exist yet no clear guidelines for optimal surgical technique for this disorder have been established.

In this study, two new techniques described in the treatment of massive, irreparable rotator cuff tears were explored; the insertion of a subacromial balloon spacer and superior capsular reconstruction. Their ability to restore glenohumeral joint kinematics was examined in cadaveric specimens with surgically created massive, …

Rural Ontario Youth And Mental Wellness, Brad Ross

Electronic Thesis and Dissertation Repository

Currently, there is a significant lack of knowledge regarding rural Ontario youth and their mental wellness. This study addresses the following research questions: 1) How do rural youth maintain mental wellness? and 2) What factors facilitate or hinder the mental wellness of rural youth from their perspective? Eight rural participants, four male and four female, aged 16-23 provided data via one on one interviews. It was found that many rural youth have adapted to utilize their rural environment, social support, and intrapersonal techniques to maintain their mental wellness. Furthermore, four main themes act as both facilitators and hindrances to their …

Aesthetic Outcome Of Maxillomandibular Advancement Surgery For The Treatment Of Obstructive Sleep Apnea, Jennifer Curran

Electronic Thesis and Dissertation Repository

Introduction:

Obstructive sleep apnea (OSA) is a common sleep disorder in which complete or partial airway obstruction causes disruptive sleep and excessive daytime sleepiness. Highly successful treatment outcomes for OSA utilizing maxillomandibular advancement (MMA) surgery have been reported. However, due to the large degree of surgical advancement that is performed, concerns may exist regarding the final aesthetic result.

Objectives:

To evaluate facial profile changes in patients treated for OSA with MMA surgery utilizing panels of oral and maxillofacial surgeons (OMFS), orthodontists (ORTHO) and laypeople (LAY).

Methods:

This was a retrospective cohort analysis. Pre- and post-treatment silhouettes of patients who underwent …

Power Reserve Following Ramp-Incremental Cycling To Exhaustion: Implications For Muscle Fatigue And Function, Michael D. Hodgson

Electronic Thesis and Dissertation Repository

In ramp-incremental cycling exercise, some individuals are capable of producing power output (PO) in excess of that produced at their limit of tolerance (LoT) while others cannot. This study sought to describe the: 1) prevalence of a “power reserve” within a group of young men (n=21; mean ± SD: age 25±4 years; V̇O_2max45±8 ml•kg^-1•min^-1); and 2) muscle fatigue characteristics of those with and without a power reserve. Power reserve was determined as the difference between peak PO achieved during a ramp-incremental test to exhaustion and maximal, single-leg isokinetic dynamometer power. Pre- versus post-exercise changes …

When Patients Ask To Die: The Role Of Nurses In Medical Assistance In Dying, Laura Sheridan

Electronic Thesis and Dissertation Repository

Canadians are increasingly living with chronic illness heightening the importance of palliative and end of life care. Nurses have significant involvement in end of life care which, in Canada, may now include medical assistance in dying (MAiD). This qualitative study used interpretive description to explore the perspectives of nine palliative care nurses regarding best practices in care related to MAiD. The analysis produced three overarching themes of: (a) Business as usual which reflects participants’ perspective that MAiD is an aspect of existing practices in end of life decision making in palliative care; (b) Nursing role within MAiD discusses the importance …

Exploiting Fission Yeast Genetic Interaction Data To Identify Disease-Specific Drug Targets For Tuberous Sclerosis Complex, Ashyad Rayhan

Electronic Thesis and Dissertation Repository

Tuberous sclerosis complex (TSC) is an inherited genetic disorder caused by loss-of-function mutations in either TSC1 or TSC2. Their respective gene products regulate the mechanistic target of rapamycin (mTOR) signaling pathway, which serves as an activator of cellular proliferation, metabolism, and cell survival. Orthologs of the TSC1 and TSC2 genes exist in a wide range of organisms, including the commonly used and genetically tractable model eukaryote, Schizosaccharomyces pombe. To better understand the functional roles of S. pombe tsc1 and tsc2, I exploited recent advances in genetic interaction biology to identify and characterize genes that modulate the phenotypic …

Friction Testing Of Contemporary Self-Ligating Appliance Systems, Michael Greene

Electronic Thesis and Dissertation Repository

Background: Resistance to tooth movement is multifactorial, with friction (FR) one of many important components. There is limited data comparing contemporary Passive and Active self-ligating bracket (SLB) systems in terms of FR created by archwire engagement. Aim: To compare classical FR in contemporary SLB systems and traditional twin brackets in vitro, and to identify the point of initiation of bracket-archwire engagement. Materials & Methods: Nine bracket systems of .022-in slot size were FR tested: Victory Series (3M Unitek) with elastic ligature (control); Passive SLB systems Damon Q (Ormco), Carriere SLX (Henry Schein), H4 (Ortho Classic), Altitude …

Binding Of Salivary Proteins To Orthodontic Brackets, Maria Pia Canales

Electronic Thesis and Dissertation Repository

Objectives: The aim of this study was to investigate the effect of different orthodontic materials on the formation of the protein pellicle on the bracket surface.

Materials and Methods: We used X-ray Photoelectron Spectroscopy (XPS) to analyze the atomic composition of orthodontic metallic and ceramic brackets. Following XPS, the brackets were immersed in human whole saliva supernatant for 2-hour incubation at 37°C. Hydroxyapatite (HA) discs were used as control. Acquired pellicle was harvested with sonication for each group, and liquid chromatography electrospray ionisation mass spectrometry was used for protein identification.

Results: Differences reported by XPS and mass spectrometry were noted …

Design And Evaluation Of Neurosurgical Training Simulator, Trinette L. Wright

Electronic Thesis and Dissertation Repository

Surgical simulators are becoming more important in surgical training. Consumer smartphone technology has improved to allow deployment of VR applications and are now being targeted for medical training simulators. A surgical simulator has been designed using a smartphone, Google cardboard 3D glasses, and the Leap Motion (LM) hand controller. Two expert and 16 novice users were tasked with completing the same pointing tasks using both the LM and the medical simulator NeuroTouch. The novice users had an accuracy of 0.2717 bits (SD 0.3899) and the experts had an accuracy of 0.0925 bits (SD 0.1210) while using the NeuroTouch. Novices and …

Manipulation Of Auditory Feedback In Individuals With Normal Hearing And Hearing Loss, Le Truc Linh Vaccarello

Electronic Thesis and Dissertation Repository

Auditory feedback, the hearing of one’s own voice, plays an important role in the detection of speech errors and the regulation of speech production. The limited auditory cues available with a hearing loss can reduce the ability of individuals with hearing loss to use their auditory feedback. Hearing aids are a common assistive device that amplifies inaudible sounds. Hearing aids can also change auditory feedback through digital signal processing, such as frequency lowering. Frequency lowering moves high frequency information of an incoming auditory stimulus into a lower frequency region where audibility may be better. This can change how speech sounds …

Nicotinamide Phosphoribosyltransferase In Smooth Muscle Cells And Aortic Integrity, Alanna R. Watson

Electronic Thesis and Dissertation Repository

The thoracic aortic wall can degenerate over time with catastrophic consequences. Vascular smooth muscle cells (SMCs) can resist and repair artery damage but their capacities decline with age and stress. Recently, production of NAD⁺ via nicotinamide phosphoribosyltransferase (Nampt) has emerged as a mediator of cell vitality. However, a role for Nampt in aortic SMCs in vivo is unknown. To study the role of Nampt in SMCs, mice with Nampt-deficient SMCs were generated. SMC-Nampt knockout mice were viable but had mildly dilated aortas. Infusion of angiotensin II led to aortic medial hemorrhage and dissection. SMCs had indicators of premature …

Nursing Practice During A Mission In Nepal: Ethics And Leadership, Lorena M. Bonilla

Electronic Thesis and Dissertation Repository

The ability of nurses to reflect or critically examine the impact of professional standards of practice, legal guidelines, and ethical frameworks that influence and guide their practice is essential to help patients achieve quality of life and wellness. Regardless of the location and setting where nursing takes place, contextual factors such as the benefits and potential harm resulting from the care provided, availability of resources, the nurse’s scope of practice, and evidence-based practice guidelines, all affect a nurse’s ability to practice in a safe, ethical, competent, caring, and compassionate manner.

Using an exploratory case study to investigate nurses’ (n=9) view …

The Feasibility Of Square-Stepping Exercise As A Universal Intervention For Older Adults With Chronic Disease To Improve Cognitive And Physical Function, Erin M. Shellington

Electronic Thesis and Dissertation Repository

Square-stepping exercise (SSE) is a cognitive training program with a physical component. An instructor demonstrates a stepping pattern across a gridded mat and participants are required to memorize and repeat the patterns on their own. In community-dwelling older adults, SSE has demonstrated some benefits on global cognitive functioning (GCF), balance, functional fitness, and social interaction.

Aims: to investigate the feasibility and efficacy of SSE in varied populations and settings to improve mobility and cognition. Populations included older adults with: knee osteoarthritis (OA), type 2 diabetes mellitus (T2DM) and self-reported cognitive complaints (sCC), and those living in long-term care (LTC) …

E-Visits For Early Post-Operative Visits Following Orthopaedic Surgery Can They Add Efficiency Without Sacrificing Effectiveness, William G. Jeffery

Electronic Thesis and Dissertation Repository

We asked 217 sport surgery and 135 total knee arthroplasty (TKA) patients to complete a questionnaire (e-Visit) before attending their two and six-week post-operative appointment. Our primary objective was to use the questions asked of patients prior to their appointment to develop a model that could be used as web-based e-Visit to predict early post-operative adverse events. Gold standard comparison was the surgeon’s opinion as to the presence or absence of an event at follow-up. Secondary objective was evaluation of a simplified model. We found good area under the curve (AUC) statistics (0.76 (95% CI 0.69 - 0.84) and 0.80 …