Quality Of Life And Subjective Outcomes Following Maxillomandibular Advancement Surgery For The Treatment Of Obstructive Sleep Apnea, Andrew D. Emanuele

Electronic Thesis and Dissertation Repository

Objective: The aim of this study was to assess outcomes related to general quality of life, daytime sleepiness and functional sleep outcomes, functional outcomes of orthognathic surgery, and facial aesthetics in patients undergoing maxillomandibular advancement (MMA) surgery for the treatment of obstructive sleep apnea (OSA).

Materials and Methods: This was a cross-sectional self-report study. A questionnaire was constructed using questions drawn from previously validated questionnaires. The survey was distributed to 25 patients who underwent MMA surgery for the treatment of OSA at LHSC in London, Ontario by a single surgeon between 2002 and 2013.

Results: The survey results showed that …

The Role Of Bone Sialoprotein In Periodontal Tissue Development And Bone Repair, Yohannes Soenjaya

Electronic Thesis and Dissertation Repository

Bone development and repair involve complex processes that include interaction between cells and their surrounding matrix. In the body, bone sialoprotein (BSP) expression is up-regulated at the onset of mineralization. BSP is a multifunctional acidic phosphoprotein with collagen-binding, hydroxyapatite nucleating, and integrin recognition (RGD sequence, which is important for cell-attachment and signaling) regions. Mice lacking BSP expression (Bsp^-/-), exhibit a bone phenotype with reductions in bone mineral density, bone length, osteoclast activation, and impaired bone healing. This thesis examined the role of BSP in tooth development and also its potential use as a therapeutic reagent for bone …

Pathophysiologic Mechanisms Of Immune-Mediated Drug Hypersensitivity Reactions To Sulfonamides, Elham A. Sultan

Electronic Thesis and Dissertation Repository

As sulfonamide hypersensitivity reactions are serious clinical problem, it is necessary to determine which patients tolerate therapy and which patients are at risk. Although the exact pathogenesis of these reactions remains unclear, the imbalance in the production and detoxification of reactive sulfamethoxazole (SMX) metabolites appears to be important in the propagation of these reactions. It is known that these reactive metabolites can cause lymphocytes toxicity and produce reactive oxygen species (ROS) which can damage proteins, lipids, and DNA. The hypothesis of this research is that there are differences in cytotoxicity and expression of oxidative stress to reactive SMX metabolites in …

Cd4+ T-Cell Mediated Microvascular Endothelial Cell Death And Chronic Cardiac Allograft Rejection Involves Necroptosis, Cecilia Yt Kwok

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Heart transplantation is the only viable option for patients with end-stage heart failure. Despite advances in immunosuppressive therapies, the rate of transplanted graft loss remains substantial. Graft loss is primarily due to tissue damage mediated by immune responses. Cell death and organ rejection can occur as an active molecular process through apoptotic and necrotic pathways. We now recognize that cell death may also ensue through a newly described form of programmed necrotic cell death, termed necroptosis that involves receptor-interacting protein kinase (RIPK) 1/3. In this study, I aim to establish the role of RIPK3 in T cell-mediated chronic cardiac allograft …

Eating And Swallowing, Oral Health, And Saliva Production, Rebecca H. Affoo

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Eating and maintaining optimal nutrition are essential to health and quality of life. In both health and disease, eating is influenced by multiple factors including swallowing, oral health, and saliva production. Perturbations to any, or all, of these inter-related factors may result in consequences that negatively affect the health and wellness of an individual. Eating and swallowing impairment are common symptoms of neurodegenerative diseases such as dementia, and these symptoms are associated with a host of negative sequelae such as malnutrition, dehydration, aspiration pneumonia, and reduced quality of life. The studies reported in this dissertation explored elements of eating and …

An Evaluation Of The Constructed Frankfort Mandibular Plane Angle Bisector (Cfmab) Wits' Appraisal In The Assessment Of Anteroposterior Jaw Relationships, Derek R. Tomson

Electronic Thesis and Dissertation Repository

For proper orthodontic diagnosis and treatment planning, an accurate measurement of the relationship of the maxilla to the mandible in the sagittal plane is required. The ANB measurement has long been the gold standard for explaining this association. The purpose of this longitudinal study was to evaluate three linear measurements of the maxillomandibular anteroposterior relationship and determine which one best correlates with ANB. The constructed Frankfort horizontal-mandibular plane angle bisector (cFMAB-Wits), maxillomandibular bisector (MMB-Wits), and Frankfort-mandibular plane angle bisector (FMAB-Wits) were measured using a Wits’-type analysis and compared to ANB.

Pre-treatment (TO), immediate post-treatment (T1), and two years post-retention (T2) …

Evaluating The Pathological And Behavioural Consequences Of Injecting Amyloid Beta Oligomers In The Rat, Ryan S. Wong

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Alzheimer’s disease (AD) is the most common form of dementia and is characterized by progressive neuronal loss and cognitive decline. Currently, no therapeutic treatments are available and our understanding of the disease progression is still unclear. Amyloid beta oligomers (AβO) are potent neurotoxic proteins and may be a potential initiator of the progression of AD. The purpose of this project was to identify the spatial and temporal consequences of injecting AβO into the rat brain by evaluating pathological and behavioural outcomes. We hypothesized that injecting AβO into the rat brain will result in microglial response as well as behavioural and …

Apodized-Aperture Pixel Design X-Ray Detector For Improvement Of Detective Quantum Efficiency At High Spatial Frequencies, Elina Ismailova

Electronic Thesis and Dissertation Repository

The detective quantum efficiency (DQE) is a characteristic of x-ray imaging systems describing how well a system can produce high signal-to-noise ratio images compared to an ideal detector. In medical radiography, increases in DQE result directly in increases in image SNR for a given x-ray exposure, and improved SNR has been shown to improve breast cancer detection rates in screening programs. Typically, modern x-ray detectors have DQE values about 0.6 to 0.7 at low spatial frequencies and 0.2 to 0.3 or less at high spatial frequencies. We describe a method to improve the high frequency DQE by developing a novel …

Hyperpolarized 129xe Magnetic Resonance Imaging Of Radiation-Induced Lung Injury, Ozkan Doganay

Electronic Thesis and Dissertation Repository

Lung cancer is the largest contributor to cancer-related mortality worldwide. Only 20% of stage III non-small cell lung cancer patients survive after 5-years post radiation therapy (RT). Although RT is an important treatment modality for lung cancer, it is limited by Radiation-Induced Lung Injury (RILI). RILI develops in two phases: (i) the early phase (days-weeks) referred to radiation pneumonitis (RP), and (ii) the late phase (months). There is a strong interest in early detection of RP using imaging to improve outcomes of RT for lung cancer. This thesis describes a promising approach based on ¹²⁹Xe gas as a contrast …

Expression Of Human Kallikrein Protein And Mrna In Maxillofacial Cysts And Tumours, Karl Kevin Cuddy

Electronic Thesis and Dissertation Repository

Non-inflammatory odontogenic cysts and tumours vary in clinical appearance and can cause widespread destruction and deformation of the face. Proteases may play a role in the differing pathogenesis of these cysts and tumours. Human kallikrein proteins (KLKs) are a group of 15 serine proteases implicated in a variety of signaling and regulatory roles. This study evaluated the ameloblastoma, keratocystic odontogenic tumour (KOT), dentigerous cyst, lateral periodontal cyst, nasopalatine duct cyst and odontoma for the presence of KLK 3, 4, 5, 9 and 11 utilizing immunohistochemistry. Secondarily, we evaluated ameloblastoma for expression of KLK 1-15 mRNA using reverse transcription-polymerase chain reaction. …

Epidermal Growth Factor Receptor In Joint Health And Osteoarthritis, Michael A. Pest

Electronic Thesis and Dissertation Repository

Osteoarthritis (OA) is one of the most prevalent musculoskeletal diseases in the world. Our laboratory has shown that epidermal growth factor receptor (EGFR) signalling is involved in the process of cartilage degeneration in OA. Regulation of EGFR signalling by mitogen-inducible gene 6 (Mig-6) and dual specificity phosphatase 1 (DUSP-1) allows for signal modulation, and mouse models have linked these proteins to joint pathologies. Failure to control EGFR signalling may be involved in OA progression leading to my overarching hypothesis: regulation of EGFR signalling is essential for maintenance of joint health.

I initially tested the role of Mig-6 in cartilage health …

Role Of Cerebrovascular Abnormality In Neurodegenerative Disease And Subcortical Ischemic Disease: Ct Perfusion And Pet Imaging, Jun Yang

Electronic Thesis and Dissertation Repository

Clinical studies indicate that about 30% ~ 50% of patients have cognitive impairment after the first or recurrent stroke. Ischemic injury, particularly subcortical lesions, caused by stroke has been demonstrated to further exacerbate cognitive impairment of Alzheimer’s disease (AD) and vascular dementia. However, the mechanisms whereby cerebrovascular abnormalities contribute to neurodegeneration at early stage of disease and eventually to cognitive decline remain unclear. CT perfusion and positron emission tomography (PET) were used to investigate early mechanisms in a rat comorbid model of cerebral ischemia (CI) and β-amyloid (Aβ, a pathological hallmark of AD) toxicity, and in patients with small subcortical …

Interpretation Of Mutations, Expression, Copy Number In Somatic Breast Cancer: Implications For Metastasis And Chemotherapy, Stephanie Dorman

Electronic Thesis and Dissertation Repository

Breast cancer (BC) patient management has been transformed over the last two decades due to the development and application of genome-wide technologies. The vast amounts of data generated by these assays, however, create new challenges for accurate and comprehensive analysis and interpretation. This thesis describes novel methods for fluorescence in-situ hybridization (FISH), array comparative genomic hybridization (aCGH), and next generation DNA- and RNA-sequencing, to improve upon current approaches used for these technologies. An ab initio algorithm was implemented to identify genomic intervals of single copy and highly divergent repetitive sequences that were applied to FISH and aCGH probe design. FISH …

Investigating The Regulation Of A Fatty Acid Efflux Pump In Methicillin Resistant Staphylococcus Aureus, James Et Schneider

Electronic Thesis and Dissertation Repository

Community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) strain USA300 has rapidly achieved pandemic status in the community setting. To persist on human hosts, USA300 requires mechanisms to overcome innate immune defenses of the skin, which include antimicrobial unsaturated free fatty acids (uFFAs). This study evaluated efflux mediated mechanisms of resistance to uFFA. tet38 encoding an efflux pump that was previously implicated in resistance to palmitoleic acid, was found to have no role in resistance to uFFA. Conversely, the farE encoded efflux pump conferred resistance to linoleic and arachidonic acid, but not palmitoleic acid. farE expression was induced by uFFA, but …

Characterization Of The Atsr/Atst Global Regulatory Pathway In Burkholderia Ceocepacia, Maryam Khodai-Kalaki

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Phosphorylation cascades governed by two-component signal transduction systems provide key signalling mechanisms in bacteria, simple eukaryotes and higher plants, allowing them to translate signals into adaptive responses. These regulatory pathways consist of a transmembrane sensor protein that responds to an environmental cue leading to autophosphorylation, followed by the transfer of the phosphate to a cytoplasmic response regulator. Here, I study AtsR, a membrane-bound hybrid sensor kinase of Burkholderia cenocepacia, that negatively regulates quorum sensing related virulence factors such as biofilm, type 6-secretion and protease secretion. B. cenocepacia is a Gram-negative opportunistic pathogen which causes severe, chronic respiratory infections in …

The Application Of The Ultrafine Technology In Improving The Biocompatibility And Osteo-Inductivity Of Dental Implants, Nicholas Y. Hou

Electronic Thesis and Dissertation Repository

Dental implants are very effective medical devices. However, although stable, the conventional titanium implants are not very bioactive which in some instances could reduce their efficacy. This thesis described the research progress of using polymeric ultrafine-particles with bioactive additives to enrich the surface of titanium substrate, thereby increasing the biocompatibility and osteo-inductivity of the biomaterial. During this doctoral project, three different types of polymers were examined, initially the conventional polyester, and later the novel epoxy as well as the epoxy/polyester hybrid polymers. Physical characterizations confirmed that all of the coating powders were ultrafine particles, and homogeneous surfaces were constructed from …

Contribution Of Enhanced Intrinsic Apoptosis To Renal Ischemia Reperfusion Injury In The Absence Of Ripk3 And Caspase-8 Dependent Regulated Cell Death, Ron Sung

Electronic Thesis and Dissertation Repository

Ischemia-reperfusion injury (IRI) contributes to reduced long term organ transplant survival. IRI is a complex process related to multiple mechanisms including regulated forms of cell death such as apoptosis and necroptosis. We have previously shown that preventing necroptosis by genetic elimination of the key molecule (RIPK3) or apoptosis inhibition through caspase-8 silencing are of benefit in kidney IRI. As these pathways of regulated cell death are unique, we tested the hypothesis that deletion of both RIPK3 and caspase-8 activity in kidneys would synergistically improve renal IRI, compared to inhibition of individual pathways. Interestingly we found that IRI was not improved …

Novel Protective Salivary Peptides And The Chitosan Nanoparticles Delivery System, Flavia Zaidan Cardoso Salina

Electronic Thesis and Dissertation Repository

As a result of its protein composition, saliva performs many essential functions that contribute to oral homeostasis. However, salivary proteins suffer quick degradation in the oral cavity, which decreases the protective potential of that fluid (Chapter 2). Using scanning electron microscopy (SEM), we evaluated the effect of our novel salivary peptides DR9, DR9-DR9, DR9-RR14 and RR14 on the crystallization of calcium oxalate (CaOx). All peptides containing DR9 showed significant inhibitory effect on the crystallization of CaOx, whereas RR14 showed no effect (Chapter 3). Next, we tested the adsorption behavior of our chitosan nanoparticles (CHNP) delivery system to hydroxyapatite (HA) surface …

The Role Of Bone Sialoprotein In The Tendon-Bone Insertion, Ryan M. Marinovich

Electronic Thesis and Dissertation Repository

Tendons and ligaments insert into bone through a transitional tissue termed the enthesis which is susceptible to injury and difficult to repair. Entheses contain a region of calcified fibrocartilage (CFC), however mineral-associated proteins in this tissue remain poorly characterized. Bone sialoprotein (BSP) is a phosphoprotein associated with mineralizing tissues. In these studies BSP was identified in the CFC of entheses by immunohistochemistry. Analysis of the entheses of Bsp^-/- mice indicate abnormalities in the CFC. Compared to controls, the CFC of the quadriceps tendon enthesis is 28% and 41 % longer in 15 week and 14 month old Bsp^{-/- …}

Investigating The Mechanism Of Ectopic Mineralization In A Mouse Model Of Diffuse Idiopathic Skeletal Hyperostosis (Dish), Neil A. Tenn

Electronic Thesis and Dissertation Repository

Equilibrative nucleoside transporter 1 (ENT1) transfers adenosine across plasma membranes. Mice lacking ENT1 (ENT1^-/-) develop pathological calcification of spinal tissues resembling diffuse idiopathic skeletal hyperostosis (DISH) in humans. Our goal was to investigate the mechanism underlying ectopic mineralization in ENT1^-/- mice. We detected aberrant alkaline phosphatase (ALP, promoter of mineralization) activity in the annulus fibrosus (AF) of ENT1^-/- mice. In vitro, AF cells from ENT1^-/- mice exhibited greater ALP activity than cells from wild-type (WT) mice. Inhibition of ENT1 in the presence of extracellular adenosine modeled in WT cells the phenotype of ENT1 …

The Experiences Of Criminalized Women When Accessing Health Care Services During Incarceration Within Provincial Jails: A Critical Narrative Study, Shamiram Zendo

Electronic Thesis and Dissertation Repository

Abstract

There has been a noticeable increase in the imprisonment of women in Canada, within the last 20 years. The purpose of this critical inquiry was to capture and promote the voices and stories of criminalized women, in order to serve their interest. Five individual in-depth interviews were conducted with women, who were incarcerated in provincial jail. A critical paradigm was used to explore how socioeconomic and gender inequalities, embedded in the social, political, and historical contexts, influenced criminalized women’s experiences when accessing health care. The findings of this study described how criminalized women experience fragmentation in health care access, …

Contribution Of The Dorsolateral Prefrontal Cortex To Attentional And Mnemonic Processes In Visual Search, Brandon Belbeck

Electronic Thesis and Dissertation Repository

A key characteristic of selective visual attention is that it may be deployed on the basis of our knowledge or goals of the task at hand. Here, we used cryogenic deactivation to investigate the contribution of the dorsolateral PFC to cognitive flexibility and working memory, as well as their relation to the deployment of attention. Macaque monkeys performed visual search tasks requiring them to foveate a target in an array of stimuli. These included a feature search, a constant-target conjunction search, a variable-target search and variable-target with delay search task, with each being more cognitively demanding than the last. Bilateral …

Underlying Mechanisms Regulating Gingival Healing And Fibrosis, Shawna Soheun Kim

Electronic Thesis and Dissertation Repository

Successful wound healing involves tightly controlled regulation of extracellular matrix (ECM) deposition and remodeling, and myofibroblast-mediated wound contraction, to restore normal tissue function. However, these events involved in healing are also associated with development of tissue fibrosis, which is characterized by excessive deposition of ECM and the presence of myofibroblasts. Increasing evidence suggests that periostin is a critical player in regulating skin healing and fibrosis. In contrast to most adult tissues, gingival connective tissue is known to heal more rapidly and with less scarring, yet is still associated with fibrosis, such as drug-induced gingival enlargement. The aim of this study …

The Utility Of A Protection Motivation Theory Framework For Understanding Sedentary Behaviour, Tiffany S. Wong

Electronic Thesis and Dissertation Repository

This study aimed to 1) examine the factor structure and composition of sedentary-derived Protection Motivation Theory (PMT) constructs and 2) determine the utility of these constructs in predicting general and leisure sedentary goal intention (GI), implementation intention (II), and sedentary behaviour (SB). PMT, GI, II constructs, and a modified SB questionnaire were completed by undergraduate students. After completing socio-demographics and the PMT items (n = 787), participants were randomized to complete general or leisure intention and SB items. Irrespective of model, principal axis factor analysis revealed that the PMT items grouped into eight coherent and interpretable factors. Using linear …

Nursing Students' Understanding And Enactment Of Resilience: A Grounded Theory Study, Andrew T. Reyes

Electronic Thesis and Dissertation Repository

The purpose of this study was to explore nursing students’ understanding and enactment of resilience. Stress is considered to be a major factor affecting the health, well-being, and academic performance of nursing students. Resilience has been extensively researched as a process that allows individuals to successfully adapt to adversity and develop positive outcomes as a result. However, relatively little is known about the resilience of nursing students. A constructivist grounded theory study design was used. In-depth individual interviews were conducted with 38 nursing students enrolled in a four-year, integrated baccalaureate nursing degree program at a university in Ontario, Canada. Face-to-face …

An In-Vitro Comparison Of Different Palatal Sites For Orthodontic Miniscrew Insertion: The Effect Of Bone Quality And Quantity On Primary Stability, Carine Bourassa

Electronic Thesis and Dissertation Repository

Introduction: The maxillary hard palate is a desirable location for orthodontic miniscrew (OMS) placement. The related anatomy is well known, but little data exists regarding the primary stability of palatal OMSs.

Purpose: To assess the quality and quantity of human cadaveric palatal bone at different insertion sites using microCT imaging, and to determine their effect on the primary stability of OMSs.

Materials and methods: One hundred and thirty OMSs (VectorTAS^TM, 6 mm) were inserted into ten human cadaveric maxillary hard palates and maximal insertion torques (IT) were recorded. MicroCT images were obtained before and after OMS insertion for …

Clinical Outcomes Of Maxillomandibular Advancement Surgery For The Treatment Of Obstructive Sleep Apnea, Brian L. Phee

Electronic Thesis and Dissertation Repository

Objective: To evaluate clinical and radiographic treatment outcomes after maxillomandibular advancement (MMA) surgery on subjects suffering from obstructive sleep apnea (OSA).

Materials and Methods: This was a retrospective cohort analysis. Subjects underwent pre- and post-surgical polysomnography (PSG) studies and were also asked to complete a subjective self-assessment via the Epworth Sleepiness Scale (ESS) questionnaire. Twenty-two patients (11 male, 11 female) met the inclusion criteria.

Results: The mean pre-surgical apnea-hypopnea index (AHI) score was 48.4 (+/-31.3) and mean ESS score was 11.6 (+/-4.6). After surgery, the mean AHI reduced to 14.0 (+/-15.0) and ESS reduced to 5.7 (+/-3.5). Treatment success was …

An Evaluation Of The Frankfort Mandibular Plane Angle Bisector (Fmab) Wits Appraisal In The Assessment Of Anteroposterior Jaw Relationships In Class Ii Individuals, Harbinder Sangha

Electronic Thesis and Dissertation Repository

Accurate diagnosis and treatment planning are of vital importance to practicing orthodontists. The purpose of this longitudinal study was to evaluate the reliability and validity of the Frankfort Mandibular Plane Angle Bisector (FMAB) reference plane in the assessment of anteroposterior discrepancies in a sample of Class II Division 1 individuals. Comparisons were made between the FMAB, ANB angle, and maxillo-mandibular Bisector (MMB) in both treated and control samples of Class II Division 1 patients.

The data was collected from pre-treatment (T0), immediate post-treatment (T1) and two year post-retention (T2) lateral cephalograms of 40 female and 36 male Class II Division …