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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 …

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 …

Determination Of The Protective Capacity Of Hand Wraps In Combat Athletes Using Force Analysis, Eva M. Gusnowski

Electronic Thesis and Dissertation Repository

Upper extremity injuries are common in combat athletes, and are highest in the hand/wrist. Although protective hand gear is used, there is a paucity of research investigating its effectiveness. This study addressed this knowledge gap by measuring the level of force transmitted to the hand during striking using two types of hand wraps. This prospective cross over study included six combat athletes. A load cell was placed over the proximal phalanges/metacarpophalangeal joints and was used to measure sustained peak force during striking while covered with either standard linear or gel-reinforced hand wraps and boxing gloves. The gel reinforced wraps consistently …

Anatomical And Functional Lung Imaging With Volumetric Computed Tomography In Non-Small Cell Lung Cancer, Heather Young

Electronic Thesis and Dissertation Repository

Non-small cell lung cancer (NSCLC) is one of the most diagnosed cancers in Canada, and the leading cause of cancer deaths. A significant challenge in treating NSCLC is balancing aggressive treatment with the potentially severe side effects. In radiation therapy, the management of respiratory motion and the risks of radiation-induced lung injury (RILI) pose significant challenges. 4-dimensional computed tomography (4D-CT) is an important part of motion management, but images often suffer from motion-induced artifacts. Volumetric CT scanners with wide axial field-of-view (aFOV) may reduce these artifacts and present an opportunity to advance CT-based functional lung imaging.

Chapter 2 presents a …

Electrochemical Deposition Of Calcium Phosphate-Based Coatings Onto Porous Ti Using Organic Phosphorus Sources, Clement Lee

Electronic Thesis and Dissertation Repository

The study and commercialization of calcium phosphate (Ca-P) coatings has occurred for several decades. However, this has typically involved the use of hydroxyapatite. This thesis presents the synthesis of different Ca-P-based coatings that has not been studied. Anodic oxidation was employed to create a porous Ti substrate, while pulsed electrochemical deposition was used to deposit the coating onto the Ti. The first coating synthesized was a calcium phosphoserine (Ca-pSer) complex, which contained two different morphologies: a flower-like structure at low deposition time and a unique cubic morphology at higher deposition times. Next, an amorphous calcium phosphate coating was synthesized and …

Extrinsic And Intrinsic Factors Influencing Homeostasis And Repair In Oral Tissues, Georgia Nikoloudaki

Electronic Thesis and Dissertation Repository

The oral tissues, including gingiva and buccal mucosa, heal rapidly with minimal scar formation. Although in the oral cavity, the palatal mucosa is associated with excessive scarring in response to injury. In this thesis, first, I investigated the complex relationship between cells and their microenvironment using wound healing models in which extracellular matrix composition and mechanical stiffness affect cellular responses during acute wound repair. I also determined how intrinsic differences of cells recruited during healing contribute to wound resolution.

In Chapter 2, I first investigated cell-extrinsic factors, specifically the influence of the pro-fibrotic matricellular protein periostin on palatal healing. Using …

Evaluating The Utility Of S100a7 In Identifying Oral Dysplastic Lesions That Will Progress To Oral Squamous Cell Carcinoma, Jeff Soparlo

Electronic Thesis and Dissertation Repository

Title: Evaluating the utility of S100A7 in identifying oral dysplastic lesions that will progress to oral squamous cell carcinoma Introduction: Recently, S100A7 has been shown to be a potential useful marker for identifying oral lesions at risk of transformation from dysplasia to squamous cell carcinoma. Our hypothesis is that high S100A7 protein expression predicts the transformation of oral epithelial dysplasia to malignancy. The objective of our study is to semi-quantitatively evaluate the level of S100A7 expression in dysplastic lesions which have transformed into oral squamous cell carcinoma using immunohistochemistry, and correlate these results with other methods of analysis including the …

Spin And Distortion In Surgical Trials, Andrea Mataruga

Electronic Thesis and Dissertation Repository

Research problem: Randomized controlled trials (RCTs) are essential; however, their validity can be threatened through distortion or spin. This study quantifies publication bias and distorted outcome reporting.

Methodology: All surgical RCTs registered on ClinicalTrials.gov from 1997-2017 were identified and a sample was obtained through random and intentional selection. Failure to publish (proportion of studies that remain unpublished), outcome distortion (changing intended outcomes), and spin (distorted presentation) were explored. Comparisons were made for positive versus negative studies and for high-income (HICs) versus low-middle income countries (LMICs).

Results: In total, 13,761 RCTs were registered (median enrollment size = 96, 94% from …

Identification Of Dna Methylation Episignatures For Classification And Phenotype/Genotype Correlation In Mendelian Neurodevelopmental Disorders, John Reilly

Electronic Thesis and Dissertation Repository

ABSTRACT: Diagnosis for neurodevelopmental disorders poses numerous challenges, related to the lack of specific findings and limited understanding of clinical impact of the majority of genetic variation. Epigenomics mechanisms involve chemical modifications in DNA that involve a range of cellular mechanisms. DNA methylation is an epigenetic mechanism involving addition and removal of methyl groups to cytosine residues. These methylation signals form episignatures; patterns of methylation that can be used as biomarkers capable of differentiating neurodevelopmental disorders. EpiSigns have enabled molecular diagnosis of a number of genetic conditions, classification of variants of unknown significance, and provided insights into the pathophysiology of …

The Effect Of Modifications To Intermaxillary Orthodontic Elastics On Force Levels And Degradation Over Time, Steven Dent

Electronic Thesis and Dissertation Repository

Introduction: Orthodontic elastics are frequently used in orthodontic treatment but there is little research into how to modify their prescription to improve their performance. The aim of this study was to evaluate potential wear modifications to a standard Class II intermaxillary elastic prescription on force levels and force degradation over time.

Methods: For this in vitro study, Ormco (OR) and American Orthodontic (AO) latex elastics had five modifications made to a standard 1/4”/4.5oz control elastic (Group 1). These included an increase of force level by one unit to 6 or 6.5oz (Group 2); a decrease in lumen size to 3/16” …

"Pain Is What The Patient Says It Is": A Secondary Analysis Of Nurses’ Reflections On The Term Pain Catastrophizing, Riana Longo

Electronic Thesis and Dissertation Repository

Background: Pain catastrophizing is a widely used concept; however, many have argued that it delegitimizes and decontextualizes patients’ pain experiences. Previous studies identified that patients and clinicians think the term is stigmatizing; however, nurses’ perceptions are underrepresented. Nurses offer a unique perspective that is critical to explore to foster positive change and improve patient outcomes. Objectives: This thesis aims to summarize the current literature on pain catastrophizing perspectives from clinicians and patients, analyze nurses’ perspectives, and uncover any underlying issues with the term itself. Methods: This thesis consisted of a two-stage design. The first study is a scoping review that …

Cost-Effective Non-Destructive Testing Of Biomedical Components Fabricated Using Additive Manufacturing, Santiago Fabian Cobos

Electronic Thesis and Dissertation Repository

Biocompatible titanium-alloys can be used to fabricate patient-specific medical components using additive manufacturing (AM). These novel components have the potential to improve clinical outcomes in various medical scenarios. However, AM introduces stability and repeatability concerns, which are potential roadblocks for its widespread use in the medical sector. Micro-CT imaging for non-destructive testing (NDT) is an effective solution for post-manufacturing quality control of these components. Unfortunately, current micro-CT NDT scanners require expensive infrastructure and hardware, which translates into prohibitively expensive routine NDT. Furthermore, the limited dynamic-range of these scanners can cause severe image artifacts that may compromise the diagnostic value of …

Torque Expression Of Active And Passive Self-Ligating Orthodontic Brackets With Different Stainless Steel Wire Sizes, Jennifer L. Boogaards

Electronic Thesis and Dissertation Repository

This investigation aimed to compare engagement angles and torquing moments generated by stainless steel (SS) wires in three active self-ligating (ASL), one passive self-ligating (PSL), and a conventional twin orthodontic bracket system control. Brackets were tested in simulations of buccal and palatal root torque using four sizes of SS wires (16x22, 17x25, 19x25, 20x20 mil). A custom 3D printed testing apparatus was developed to measure torque. After initial engagement within bracket slots, torquing moments increased with progressive rotation of brackets around wires. In general, the PSL and conventionally ligated systems generated significantly larger torquing moments than ASL systems, especially with …