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The Co-Delivery Of Syngeneic Adipose-Derived Stromal Cells And Macrophages On Decellularized Adipose Tissue Bioscaffolds For In Vivo Soft Tissue Regeneration, Hisham A. Kamoun

Electronic Thesis and Dissertation Repository

Decellularized adipose tissue (DAT) bioscaffolds are a promising platform for the delivery of pro-regenerative cell populations with the goal of promoting adipose tissue regeneration. The current study investigated the effects of seeding DAT bioscaffolds with syngeneic bone marrow-derived macrophages and/or adipose-derived stromal cells (ASCs) on in vivo soft tissue regeneration. Methods were established to derive the macrophages from MacGreen mice, which were dynamically seeded onto the DAT scaffolds alone or in combination with ASCs. Seeded and unseeded scaffolds were implanted subcutaneously into C57Bl/6 mice. At 2 and 4 weeks, cell infiltration, angiogenesis, and adipogenesis were analyzed through histology and immunohistochemistry. …

Evaluating The Utility Of Protein Biomarker, S100a7, And Diagnostic Test, Straticyte, In Predicting The Progression Of Oral Dysplasia, Lachlan Mclean

Electronic Thesis and Dissertation Repository

Five-year survival of oral cancer has remained relatively unchanged despite advancements in treatment, mostly because diagnosis is often made at an advanced stage of disease. The progression of dysplasia to oral cancer often follows a stepwise progression. Histopathology is considered the ‘gold standard’ for diagnosing dysplasia and lesions at a high risk of progression to oral cancer, but lends itself to subjectivity. The protein biomarker, S100A7, in oral dysplasia and squamous cell carcinoma has shown some predictive value for the transformation of dysplasia to cancer. Straticyte, a diagnostic test utilizing S100A7 to predict the probability of progression of oral dysplasia …

The Effect Of Pigmentation On Thermoplastic And Thermoset Elastomeric Power Chain, William Taylor

Electronic Thesis and Dissertation Repository

Aim: The purpose of the study was to determine the effect of pigmentation on force levels and their degradation over time in orthodontic power chain of different chain types and manufactures.

Materials & Methods: Groups consisted of closed power chain from American Orthodontic (AO) thermoplastic (TP) in 5 colors, AO thermoset (TS) in 2 colors, Ormco TP in 4 colors, Ormco TS in 2 colors, and Rocky Mountain Orthodontics (RMO) TS in 5 colors (18 groups total, 10 chain samples in each group). Testing was performed over a period of 6 weeks at intervals of initial (T0), 1 hour (T1), …

Discovery Of Novel Mechanisms Regulating Cancer Extravasation In The Chorioallantoic Membrane Model, Yohan Kim

Electronic Thesis and Dissertation Repository

Cancer metastasis is a multistep process that begins with the invasion of tumour cells into the stroma and migration towards the blood vessels. Tumour cells that have entered the bloodstream must then survive and leave by a process known as extravasation. Finally, extravasated cells proliferate and establish the secondary site in the metastatic cascade. Although extravasation encompasses key events during cancer cell invasion to aid in the development of effective treatments, an in vivo model that rapidly, reproducibly and economically recapitulates cancer cell extravasation is needed. Therefore, the objectives of my research were to 1) establish and validate an in …

Synthesis Of Vo2/Poly(Mma-Co-Dmemuabr) Antimicrobial/Thermochromic Dual-Functional Coating And Reactivity Ratios Study, Yixian Liu

Electronic Thesis and Dissertation Repository

Antimicrobial/thermochromic dual-functional coatings were successfully synthesized via UV-curing. The quaternary ammonium compound (QAC) N,N-dimethyl-N-{2-[(2-methylprop-2-enoyl)oxy]ethyl}undecane-1-aminium bromide (dMEMUABr) was synthesized and copolymerized with methyl methacrylate (MMA) for antimicrobial properties. Vanadium oxide (VO₂) nanoparticles were evenly dispersed within the coating, providing thermochromic properties. The dual-functional coating showed high luminous transmittance (T_lum(25°C) =36.1 %) and solar energy modulation ( T_sol=5.8 %). 90.3 % of bacteria reduction was observed against Escherichia coli within 24 h contact. To further understand the sequence distribution of the copolymer poly(MMA-co-dMEMUABr), the reactivity ratios of MMA and dMEMUABr monomer were studied and compared under thermal …

Exploring The Psychosocial Impact Of Botulinum Toxin Type-A Injections For Individuals With Oromandibular Dystonia: A Qualitative Study Of Patients' Experiences, Nada Elhayek

Electronic Thesis and Dissertation Repository

This study explored the psychosocial impact of BoNT-A injections for OMD and explored how participants judge the success of this treatment. Eight participants with OMD participated in a single semi-structured interview. Phenomenological methods were used to analyze the interview data into themes. Two themes and six subthemes emerged from the analysis of the data. The first theme, Botox has changed me and my experiences, explored the participants’ perspective of receiving BoNT-A injections and its psychosocial impact. The second theme, What communication is like for me, explored the psychosocial impact of BoNT-A on speech production and participation. Our results …

The Characterization Of The Rat Bone Sialoprotein Knockout Phenotype, Benjamin Harvey

Electronic Thesis and Dissertation Repository

Bone sialoprotein (BSP) is an extracellular phosphoprotein that has been associated with mineralizing tissues, such as the periodontium, the fibrocartilaginous enthesis, and long bone formation. In this study, we characterized the phenotype of BSP-deficient rats. Histomorphometric analysis discovered a thinning of the acellular cementum in both 20 and 50 week-old Bsp^-/- rats with no related periodontal defects and an organized periodontal ligament. Analysis of the mature quadriceps tendon (QCT) enthesis determined that BSP and osteopontin are present in the calcified fibrocartilage of wild-type rats at 14 weeks. The developing QCT enthesis of Bsp^-/- rats appears similar in mineral …

High Frequency Oscillations Are Phase-Amplitude Coupled In Stress Induced Seizures Following Traumatic Brain Injury, Paul Jung

Electronic Thesis and Dissertation Repository

Traumatic Brain Injury (TBI) often leads to the development of epilepsy, especially with the occurrence of stressful events. Stressors increase the levels of corticotropin-releasing factor (CRF) in the amygdala, which can be damaged by the secondary effects of TBI. It is hypothesized that the activity of CRF receptor type 1 (CRFR₁) in the amygdala is altered post-TBI and supports the generation of epileptiform waves, namely high-frequency oscillations (HFOs). Sprague-Dawley rats were given a moderate TBI and in vivo recordings of the amygdala were taken during the administration of an acute tail pinch stressor. The stressor increased broadband activity …

Methodologies For Metal Functionalization Of Phosphorus Based Photopolymer Networks, Vanessa Béland

Electronic Thesis and Dissertation Repository

Photopolymer networks with phosphonium cation, alkyl phosphine and olefin functionality were designed, synthesized and functionalized with metals by metathesis, coordination and hydrometallation reactions, respectively. The materials were strategically designed so that the metal functionalization step could be monitored and quantified. In some cases, this involved characterization by IR, NMR, or X-ray spectroscopic techniques, or by comparison to molecular analogues. It was found that by using a bi-functional photopolymer network, the material could be bi-metallized by orthogonal mechanisms. All metallized polymer networks were tested for their suitability as precursors to metal-containing ceramics. The polymers were pyrolyzed, and on analysis it was …

Encountering Lectins In The Recipient Mucosa: Implications Of N-Linked Glycosylation On Hiv-1 Transmission, Adam Meadows

Electronic Thesis and Dissertation Repository

Although several studies have determined key differences in envelope motifs between TF and chronic HIV-1, it is still not known what the overall glycosylation profile is that is selected for in a transmission event, as well as what contributes to this selection. Using a bottom-up approach of modifying specific viruses, determining their transmission fitness in an ex vivo tissue explant assay, and determining their glycan content, we have laid the basis for determining the overall glycan structure which is selected for in TF HIV-1. Preliminarily, we have shown that C-type lectins represent a stringent barrier to transmission and have several …

Piezo1: Proteins For Mechanotransduction And Integration Of Endothelial Shear Stress & Intravascular Pressure, Juan Garcia Robledo M.D.

Electronic Thesis and Dissertation Repository

Piezo proteins are transmembrane ion channels, specialized in detecting mechanosensitive stimuli and transduce mechanical forces into biochemical signals. Piezo proteins research has helped understand physiological mechanisms, but the integrative role that Piezo1 plays in the regulation of the microvasculature has remained unstudied. Our main objective was to characterize ex vivo microvascular responses to the blockade of Piezo1 mechanotransduction in male (n=29) and female (n=24) Sprague-Dawley (SD) rats. Gracilis arterioles (GA) and middle cerebral arterioles (MCA) were harvested for ex-vivo vessel preparations. After vessel viability confirmation, every vessel was submitted to myogenic and flow challenges under control conditions and after Grammostola …

Comorbid Metabolic Syndrome And Prodromal Alzheimer's Disease In A Rat Model, Nadezda Ivanova

Electronic Thesis and Dissertation Repository

Metabolic syndrome (MetS), the development of which is associated with high-caloric Western diet intake, represents a risk factor for mild cognitive impairment (MCI) and Alzheimer’s disease (AD) and appears to contribute to AD progression when MetS and AD are comorbid. The interaction between AD and MetS might be through white matter inflammation, since white matter abnormalities and inflammation are important early events in the etiopathogenesis of both diseases. In these investigations, the effect of a high-caloric diet (HCD), to induce metabolic disturbances, on white matter neuroinflammation and cognitive function was investigated in a transgenic (TG) rat model of prodromal AD …

Effect Of Histatin- And Statherin-Derived Engineered Salivary Peptides On Streptococcus Mutans Adhesion And On Enamel Demineralization Provoked By Cariogenic Biofilms, Lina Maria Marin

Electronic Thesis and Dissertation Repository

Dental biofilm is formed onto dental surfaces covered by a layer of specific salivary proteins and peptides named acquired enamel pellicle (AEP). It was previously demonstrated that the statherin- and histatin-derived engineered salivary peptides DR9-DR9 and DR9-RR14 were able to reduce enamel demineralization and displayed antimicrobial activity against Streptococcus mutans, respectively. However, these studies were carried under experimental conditions that did not mimic caries development induced by biofilm and sucrose exposure, the most cariogenic dietary sugar. In this thesis we assessed the effect of the engineered salivary peptides on 1) the adherence of S. mutans to hydroxyapatite (HAp), and …

Hydrating With Coconut Water, Water Or Gatorade® Results In Similar Basketball Fitness & Skill Performance During A Simulated Basketball Game, Reed Zehr

Electronic Thesis and Dissertation Repository

Coconut Water (CW), which contains a high amount of the micronutrient potassium (K+) and almost half the carbohydrate (CHO) as mainstream sports beverages, has the potential to serve as a hydration beverage for athletes who engage in intermittent, high intensity exercise, like basketball. However, no studies to date have investigated this phenomenon. The purpose of this study was to assess basketball specific performance (skill and fitness components) of university varsity basketball student-athletes during a simulated game while hydrating with three experimental treatments: water (W), CW, and Gatorade® (G). One male and five female varsity basketball athletes (n=6) each completed three …

Getting Better All The Time: Re-Evaluating Macroscopic Dental Age Estimation Standards In Egypt, Casey Kirkpatrick

Electronic Thesis and Dissertation Repository

This dissertation investigates the use of dental anthropological methods for estimating chronological age-at-death in ancient Egypt, and determines whether these methods can be improved. Tooth calcification, emergence and eruption standards are time honoured in their ability to accurately age subadults though they are compromised by the fact that populations and the sexes vary in their developmental timing. Determining sex in subadults, particularly in the infant and child cohorts, in all populations is not possible, though advances in ancient DNA methods hold promise. This dissertation provides a feasible and ethical model for developing a sex-and region-specific standard for age estimation of …

Exploring Current Topics And Trends In Anatomy Education: A Scoping Review, Alex Wolf

Electronic Thesis and Dissertation Repository

Within the field of health professional education, one finds that anatomy often presents students with a great deal of difficulty. The literature in this area is piecemeal and there is limited work available examining the whole of this topic. A scoping review was conducted to determine how students are taught anatomy across multiple disciplines (medicine, dentistry, rehabilitation sciences, and undergraduate education) and to assess for any notable differences between these populations. The results found that scholarship on anatomy instruction varies based on educational context, and medical students are the most frequently targeted student population. It also found that the use …

In Vitro Biomechanical Analyses Of The Pcl And Medial Ligaments Of The Human Knee, Alireza Moslemian

Electronic Thesis and Dissertation Repository

Previous studies have shown that surgical treatments of PCL injuries are not successful in all cases and there is room for improvement. The effectiveness of an isolated PCL reconstruction, in the setting of what actually is a multi-ligament injury, may be inadequate, and therefore the biomechanical contribution of other ligaments in a PCL-deficient knee need to be better understood.

A new apparatus was used to analyze the effect of medial ligaments transection on the kinematics of the PCL-deficient knee during simulated clinical tests and activities of daily living. We observed that the anterior translation of the medial side of the …

Role Of The Fibronectin-Binding, Collagen-Binding, T-Antigen Region During Nasopharyngeal Infection By Streptococcus Pyogenes, Akshay Sule

Electronic Thesis and Dissertation Repository

Streptococcus pyogenes is a human-specific pathogen that uses a variety of adhesion molecules in order to initiate pharyngeal infection and maintain colonization. One genomic locus that is believed to contribute to adherence is the fibronectin-binding, collagen-binding, T-antigen (FCT) region, primarily due to the inclusion of genes that encode for a pilus (tee18.1), collagen-binding protein (cpa), and fibronectin-binding protein (prtF2). The precise role of these genes and the FCT region as a whole, however, have yet to be elucidated within the context of pharyngeal infection. In this study, we utilize the M18 serotype S. pyogenes strain MGAS8232 to demonstrate that the …

Quantifying The Outcomes Of A Virtual Reality (Vr)-Based Gamified Neck Rehabilitation, Shahan Salim

Electronic Thesis and Dissertation Repository

Neck pain is a major global public health concern and adds a significant financial burden to both the healthcare system as well as people suffering from it. Additionally, it presents measurement and evaluation challenges for clinicians as well as adherence challenges and treatment barriers for the patients. We have developed a virtual reality (VR)-based video game that can be used to capture outcomes that may aid in the assessment and treatment of neck pain. We investigated: (i) performance metrics of overall accuracy, accuracy based on movement difficulty, duration, and total envelope of movement; (ii) stability across sessions; (iii) accuracy across …

Childhood Stress At Rinconada Alta (Ad 1470-1532): An Examination Of Linear Hypoplastic Enamel Defects On The Central Coast Of Peru, Jessica Lacerte

Electronic Thesis and Dissertation Repository

This MA thesis investigates non-specific childhood stress at Rinconada Alta through the analysis of linear enamel hypoplastic defects (LEH). Dental casts were taken from a sample of teeth from predominantly Inca-period, Yschma remains (with some admixture of the Late Intermediate period burials). The sample consists of 10 adult females, 11 adult males, and 5 adolescents of indeterminate sex with fully occluded adult teeth (with the exception of the third molars). This thesis employs Scanning Electron Microscopy (SEM), which increases the visibility of linear defects, to determine the frequency, age, and duration at which metabolic disruption affected enamel growth of the …

The Life Histories Of Aztec Sacrifices: A Stable Isotope Study (C, N, And O) Of Offerings From Tlatelolco And The Templo Mayor Of Tenochtitlan, Diana K. Moreiras Reynaga

Electronic Thesis and Dissertation Repository

This dissertation investigates the dietary and residential patterns, using stable carbon, nitrogen and oxygen isotope analyses, of human sacrifices from the Mexica’s (Aztec) Templo Mayor of Tenochtitlan and the Templo R of Tlatelolco (in Mexico City), and a non-sacrificial Mexica group from Ecatepec (Mexico State). These skeletal collections date to the Postclassic period (A.D. 900–1520). This work uses a biocultural approach by incorporating bioarchaeological, archaeological, isotopic, and ethnohistorical evidence to examine the life histories of the sacrifices.

The phosphate oxygen isotope analysis revealed that the individuals from Ecatepec were locals to the Basin of Mexico. Similarly, the Templo R sacrifices …

The Role Of Defective Macrophage Efferocytosis During Early Atherosclerosis In Humans, Charles Yin

Electronic Thesis and Dissertation Repository

Atherosclerosis is a chronic inflammatory disease characterized by thickening of the arterial wall from accumulation of lipoproteins and immune cells within the vessel intima, forming a lipid-rich plaque. Macrophages play a central role in atherosclerosis progression through phagocytic removal of apoptotic cells in a process termed efferocytosis. With disease progression however, macrophage efferocytosis becomes defective and uncleared apoptotic cells undergo secondary necrosis and form a necrotic core that increases the risk of plaque rupture. Despite the importance of defective efferocytosis in atherosclerosis, little is known about how efferocytosis becomes impaired. The aim of this thesis was to characterize mechanisms regulating …

Functional Magnetic Resonance Spectroscopy In First-Episode Schizophrenia: Measuring Glutamate And Glutathione Dynamics At 7-Tesla, Peter Jeon

Electronic Thesis and Dissertation Repository

Schizophrenia is a neuropsychiatric illness without known etiology or cure. Current efforts for symptom treatment still seem to leave a large portion of affected individuals without proper symptom management, with those experiencing symptom relief still having to wrestle with potential side-effects from medication trials. There has been growing evidence suggesting that glutamate and glutathione abnormalities hold major roles in development and manifestation of schizophrenia symptoms.

Magnetic resonance spectroscopy (MRS) provides a non-invasive means to observe in-vivo brain chemistry, including glutamate and glutathione. By adding a functional component to an MRS paradigm (fMRS), such as the color-word Stroop task, it is …

Endogenous, Controlled Expression Of Anti-Hiv-1 Broadly Neutralizing Antibody, Darshit Patel

Electronic Thesis and Dissertation Repository

Recently, researchers have identified a number of anti-HIV broadly neutralizing antibodies (bNAbs), such as VRC01 and N6, capable of targeting a broad range of HIV-1 strains. Passive immunization using these patient-derived bNAbs could provide temporary protection but are limited by the short antibody half-life. While current gene transfer technology allows sustained bNAb expression, it lacks the ability to control bNAb production in vivo resulting in possible autoimmunity. To address this issue of achieving controlled bNAb expression in vivo, we hypothesize that bNAb expression from transduced Flu-specific B cells can be activated and modulated by subsequent Flu immunizations in the …

The Role Of The Tau N-Terminal Phosphatase-Activating Domain And Phosphorylation At Thr175 In The Formation Of Tau Cytoplasmic Inclusions, Matthew A. Hintermayer

Electronic Thesis and Dissertation Repository

Cytoplasmic inclusions and fibrils of the microtubule-associated protein tau (tau protein) are a key neuropathological hallmark in tauopathies, including Alzheimer’s disease, chronic traumatic encephalopathy, and amyotrophic lateral sclerosis with cognitive impairment. Previous research has demonstrated that the phosphorylation of tau protein at Thr¹⁷⁵ is sufficient for the initiation of fibril formation both in vitro and in vivo. Here we use mutated tau protein constructs to demonstrate that phosphorylation at Thr¹⁷⁵ results in the aberrant exposure of an N-terminal phosphatase-activating domain (PAD). The tau PAD interacts with protein phosphatase 1 (PP1) leading to the activation of glycogen synthase …

Maternal Nicotine Exposure Induces Congenital Heart Defects In The Offspring Of Mice, Elizabeth Greco

Electronic Thesis and Dissertation Repository

Congenital heart defects are the most prevalent birth defect, and maternal cigarette smoking is a known risk factor. Nicotine replacement therapies are recommended to pregnant women who smoke to aid in smoking cessation, as this alternative is thought to be much safer compared to cigarette smoking. However, these products contain nicotine, and the safety of nicotine on the developing heart is not well known. In this thesis, a mouse model was used to test the hypothesis that maternal nicotine exposure (MNE) during pregnancy leads to congenital heart defects and coronary artery defects in the offspring of mice. MNE resulted in …

The Canadian Urban - Rural Health Disparity: The Role Of Health Lifestyles And An Alternative Explanation For Rurality's Higher Bmi Rates, Matthew J. Stackhouse

Electronic Thesis and Dissertation Repository

The Canadian urban - rural health disparity is concerning, as rural residents are more likely to experience deleterious health outcomes such as injuries, chronic conditions, obesity, and shorter life expectancy. There are several rural social-structural explanations for the disparity such as an aging population, less education attainment, greater unemployment rates, poorer working conditions, lack of health professionals, greater distance from quality health resource, and poorer health behaviours. Some of these findings have been linked to higher Body Mass Index (BMI) scores in rural areas. However, no study has considered the health lifestyle differences of urban - rural Canadians and how …

Health Policy And Social Change: Women’S Advocacy Groups And Narrative Mobilization, Jill Moffatt

Electronic Thesis and Dissertation Repository

The goal of this study is to systematically investigate the mobilization of co-created (storyteller and story-gatherer) narratives for policy and social change. A case study format investigated the mobilization of narratives by a women’s health organization in London, Ontario. Semi-structured interviews resulted in transcripts from key actors. These transcripts were thematically coded and analyzed. All interview participants emphasized that from their perspective the organization did influence health policy or social change through their narrative use. Specific policy change examples were provided by participants, and social change was subjectively recognized as realized through the creation of awareness and affirmed through audience …

Using Stable Isotopes To Understand Survival Versus Extinction Of Late Pleistocene Muskoxen, Stephanie Mabee

Electronic Thesis and Dissertation Repository

This thesis uses stable isotopes to investigate the adaptive advantages of Ovibos moschatus, a muskox, relative to now-extinct Pleistocene megafauna in eastern Beringia (Yukon Territory and Alaska), including another muskox Bootherium bombifrons. Ecological niches were defined for Ovibos and Bootherium using stable carbon and nitrogen isotope compositions of bone collagen. Plant remains trapped in modern Ovibos molars were used to determine the carbon and nitrogen isotope collagen-diet discrimination factors, which were then applied to ancient specimens. Ovibos possessed larger isotopic – and hence ecological – niches than Bootherium across eastern Beringian sites. The larger niche suggests that Ovibos …

The Role Of C-Kit And Insulin Receptor Tyrosine Kinases In Beta Cell Function And Insulin Secretion, Amanda Oakie

Electronic Thesis and Dissertation Repository

The receptor tyrosine kinases (RTKs) c-Kit and insulin receptor (IR) initiate similar intracellular signalling pathways in pancreatic beta cells to regulate beta cell proliferation, survival, and insulin secretion. Mice with a c-Kit overexpression specifically in beta cells (c-KitβTg) demonstrated improved beta cell proliferation and insulin secretion compared to control mice, and islets from c-KitβTg mice also demonstrated increased IR expression. The potential interplay between c-Kit and IR and their roles during ageing and metabolic stress are not currently known. This work reports the examination of c-Kit and IR signalling using in vitro and in vivo models to determine their effects …