Medicine and Health Sciences Commons^™

Validation Of The Flexcell®Fx-5000 Tension System To Evaluate The Expression Of Cementum Protein-1 In Human Periodontal Ligament Cells While Under Cyclical Orthodontic Tensile Force, Allison Nicholls

Electronic Thesis and Dissertation Repository

The pressure-tension theory of orthodontic tooth movement (OTM) states that there are differences in microenvironment between the tension and compressions side within the periodontal ligament, leading to differential gene expression within those zones. Cementum protein 1 (CEMP-1) is a human-specific protein localized to the root of a tooth and may play a role in OTM. The first objective was to develop a protocol to apply tensile force to human PDL cells similar to that within the tension zone during OTM. For this, the FlexCell®FX-5000 Tension system was used and fluorescent microscopy was used to confirm validity of the protocol. The …

Paediatric Serum Sickness-Like Reaction: A 10-Year Retrospective Cohort Study, Blanca R. Del Pozzo-Magaña, Awatif Abuzgaia, Barbara Murray, Michael J. Rieder, Alejandro Lazo-Langner

Paediatrics Publications

Background: Serum sickness-like reaction (SSLR) is an acute inflammatory condition affecting predominantly children. The pathophysiology remains unclear, but drugs are considered the main trigger. Objective: The aim of this study was to describe the clinical and laboratory features, triggers, and treatment modalities in children diagnosed with SSLR. Methods: We conducted a 10-year retrospective cohort study including all paediatric patients (0 to 18 years old) with query SSLR referred to the Adverse Drug Reactions Clinic at the Children's Hospital of Western Ontario. Diagnostic criteria included acute skin rash plus joint inflammation with or without fever. Results: We included 83 patients (47 …

Health Care Utilization By Immigrants With Multimorbidity: A Population Based Cross-Sectional Study Of The 2015-2016 Canadian Community Health Survey (Cchs), Chinmoy Talukder

Electronic Thesis and Dissertation Repository

Immigrants face unique healthcare barriers, which can negatively impact their health and health service use. Those with multimorbidity face a particular challenge as multimorbidity is associated with increased need for healthcare. The purpose of this study was to compare healthcare utilization, as measured by number of visits to family physicians and specialists, between immigrants and Canadian-born populations with multimorbidity, stratified by sex and for specific chronic diseases. A cross-sectional analysis using 2015-2016 Canadian Community Health Survey (CCHS) was conducted. After adjusting for relevant covariates, no statistically significant differences in visits to family physicians or specialists were observed between immigrants and …

Investigating Bone Cement Susceptibility Related Artifacts And Adhesion, Eric Kuindersma

Electronic Thesis and Dissertation Repository

Blood Oxygen Level Dependent (BOLD) functional Magnetic Resonance Imaging (fMRI) utilizes pulse sequences sensitive to changes in concentration of deoxyhemoglobin to indirectly measure neural activity. Sequences used for BOLD are sensitive to magnetic susceptibility differences that may cause signal voids. Our lab has designed an awake marmoset head coil that eliminates confounds associated with imaging an animal under anesthesia. This design requires a head chamber attached to an animal’s skull with a cement that may cause a susceptibility artifact. Motivation behind this project was to find an MRI compatible cement that remains secure to the skull with minimal artifacts. Four …

Gender-Based Violence Among Women And Girls With Disabilities In Sub-Saharan African Countries: A Scoping Review Of The Literature, Aimée Josephine Utuza

Electronic Thesis and Dissertation Repository

Despite numerous studies about gender-based violence (GBV) in Sub-Saharan Africa (SSA), little attention has been paid to violence against women and girls with disabilities. Thus, this scoping review provides an overview of the empirical literature on GBV and disability within the SSA context. Selected literature included various aspects of GBV epidemiology, prevention and response, and interventions. Other aims were to identify the gaps in the current knowledge base and to contribute to an evidence-informed framework for the development of relevant and holistic programs and policies. A key finding is that efforts to seek help are often hampered by barriers, stigmatization, …

Functional Organization Of Frontoparietal Cortex In The Marmoset Investigated With Awake Resting-State Fmri, Yuki Hori, Justine C. Cléry, David J. Schaeffer, Ravi S. Menon, Stefan Everling

Brain and Mind Institute Researchers' Publications

Frontoparietal networks contribute to complex cognitive functions in humans and macaques, such as working memory, attention, task-switching, response suppression, grasping, reaching, and eye movement control. However, there has been no comprehensive examination of the functional organization of frontoparietal networks using functional magnetic resonance imaging in the New World common marmoset monkey (Callithrix jacchus), which is now widely recognized as a powerful nonhuman primate experimental animal. In this study, we employed hierarchical clustering of interareal blood oxygen level-dependent signals to investigate the hypothesis that the organization of the frontoparietal cortex in the marmoset follows the organizational principles of the macaque frontoparietal …

The Role Of Pannexin 3 In Forced Exercise Bone Remodelling And Its Potential Implications For Osteoarthritis, Justin Tang

Undergraduate Student Research Internships Conference

Exercise such as running has been hypothesized to be a factor of osteoarthritis development. However, the relationship is unclear as differences in genetic backgrounds may influence the risk of osteoarthritis (OA). The gene Panx3 codes for the Pannexin 3 protein (PANX3), a mechanically sensitive channel that allows for the passage of various signalling molecules in both chondrocytes and osteoblasts (Boassa et al., 2007; Penuela et al., 2013; Zhang et al., 2021). We have previously shown PANX3 to be protective in traumatic osteoarthritis, however beneficial in age-induced osteoarthritis (Moon et al., 2021), suggesting that PANX3’s role in osteoarthritis development …

Erythrokeratodermia Variabilis Et Progressiva (Ekvp) Linked Cx30.3 Mutants Can Be Selectively Rescued By Co-Expression Of Wildtype Keratinocyte Connexins, Rhett O. Figliuzzi

Electronic Thesis and Dissertation Repository

Connexin 30.3 (Cx30.3) is a β-connexin encoded by GJB4 that is key in epidermal homeostasis. Eleven mutations to the GJB4 are linked to an autosomal dominant skin disease called erythrokeratodermia variabilis et progressiva (EKVP). These mutations remain largely uncharacterized, limiting therapeutic options. In this study, we characterize the expression and functional status of three EKVP-linked Cx30.3 mutants, G12D, T85P and F189Y in rat epidermal keratinocytes. We found that EKVP-linked Cx30.3 mutants were not functional due to their retention in the endoplasmic reticulum (ER), but did not upregulate BiP, an indicator of ER stress. Sub-physiological incubation and chemical chaperones (such as …

Evaluation Of Cyclic Fatigue And Bending Resistance Of Coronal Preflaring Niti File Manufactured With Different Heat Treatments, Soram Oh, Su Young Moon, Antonis Chaniotis, Eugenio Pedullá, Adel Saeed Al-Ghamdi, Fawzi Ali Al-Ghamdi, Ayman Omar Mandorah, Hiran Perinpanayagam, Kee Yeon Kum, Ove A. Peters, Seok Woo Chang

Dentistry Publications

Coronal preflaring NiTi files should possess proper hardness, resistance to fracture and flexibility. This study compared the bending resistance and cyclic fatigue resistance of three orifice preflaring NiTi files. HyFlex EDM Orifice opener (#25/12), HyFlex CM (#25/08) and One Flare (#25/09) were tested (n = 46/instrument). Bending resistance was assessed with the stress when perpendicular displacement was applied to a 3 mm point from the file tip, and was performed at either room temperature (RT, n = 10) or body temperature (BT, n = 10). Cyclic fatigue resistance was tested with an artificial ceramic root canal at RT (n = …

Neighborhood Contexts And Oral Health Outcomes In A Pediatric Population: An Exploratory Study, Vladyslav A. Podskalniy, Sharat Chandra Pani, Jinhyung Lee, Liliani Aires Candido Vieira, Hiran Perinpanayagam

Dentistry Publications

Aims: This study aimed to explore the impacts of neighborhood-level socioeconomic contexts on the therapeutic and preventative dental quality outcome of children under 16 years. Materials and Methods: Anonymized billing data of 842 patients reporting to a university children’s dental over three years (March 2017–2020) met the inclusion criteria. Their access to care (OEVCH-A), topical fluoride application (TFL-CH-A) and dental treatment burden (TRT-CH-A) were determined by dental quality alliance (DQA) criteria. The three oral health variables were aggregated at the neighborhood level and analyzed with Canadian census data. Their partial postal code (FSA) was chosen as a neighborhood spatial unit …

Non-Thermal Atmospheric Pressure Plasma-Conditioned Root Dentin Promotes Attraction And Attachment Of Primary Human Dental Pulp Stem Cells In Real-Time Ex Vivo, Yeon Jee Yoo, Min Ji Kang, Hiran Perinpanayagam, Joo Cheol Park, Seung Ho Baek, Kee Yeon Kum

Dentistry Publications

This study investigated if non-thermal atmospheric pressure plasma (NTAPP) treatment of root dentin surfaces promotes human dental pulp stem cell (hDPSCs) adhesion. Freshly extracted human single-rooted teeth (n = 36) were decoronated and cut (first vertically, then horizontally) into root dentin slices (3 mm thick). Primary hDPSCs cultures were seeded onto slices randomly assigned to pretreatment groups (n = 9/group): NaOCl (1.5%), EDTA (17%) then NTAPP (Group I); NaOCl then NTAPP (Group II); NaOCl then EDTA (Group III); and NaOCl alone (Group IV). Cell viability and proliferation were measured using MTT assay with log-linear statistical analysis. Cell attachment and spreading …

The Antimicrobial Properties Of Exogenous Copper In Human Synovial Fluid Against Staphylococcus Aureus: An In-Vitro Study, Fernando Diaz Dilernia

Electronic Thesis and Dissertation Repository

We sought to analyse the antimicrobial properties of exogenous copper in human synovial fluid against Staphylococcus aureus. We performed several in-vitro growth and viability assays to determine the capability of multiple S. aureus strains to survive in synovial fluid under different growth conditions. S. aureus UAMS-1 significantly died at 24 hours (p=0.017), and S. aureus USA300 WT survived at 24 hours. We confirmed a high sensitivity to killing with the addition of exogenous copper on both strains at 4 (p=0.011), 12 (p=0.011), and 24 hours (p=0.011). Both WT and CopAZB-deficient USA300 strains significantly died in synovial fluid, evidencing a …

Functional Performance Testing In Ice Hockey: The Role Of The Single Leg, Medial Countermovement Jump, Anthony S. Donskov

Electronic Thesis and Dissertation Repository

Due to the physical nature of the game, injuries are common in ice hockey. Injury rates have been difficult to interpret due to the inconsistencies in the definitions of injury and athlete exposure. Consensus statements on injury definitions have been developed for sports such as soccer and rugby but have not been established in ice hockey. Furthermore, many different off-ice tests are performed, but a hockey-specific performance test has not been promoted. Accordingly, the objective for this thesis was to investigate injury rates, injury definition, athlete exposure and injury type in men’s ice hockey, and providing information on a practical …

Descriptive Analysis Of Fall-Related Injuries Among Older Adults In Ontario, Nicolette Lappan

Electronic Thesis and Dissertation Repository

Falls are the leading cause of injury-related hospitalizations among older adults in Canada. The purpose of this study was to describe the characteristics of older adults who experienced fall-related injuries (FRIs) and the types of falls that caused them. We analyzed Ontario-wide secondary data from three databases (NACRS, DAD, RPDB) covering 2010-2014. Older adults (≥ 65 years) who visited emergency departments (ED) with FRIs were selected using ICD-10-CA codes for a fall and injury. Counts, measures of central tendency, and prevalence rates (crude, age- and sex-specific, age-standardized) were calculated. There were 304,610 (63.0% females) ED admissions (3,089 per 100,000 population) …

Catechol-Containing Copolymers As An Active Ingredient For Denture Adhesives, Vincent Ying Wun Kong

Electronic Thesis and Dissertation Repository

Moisture inside the mouth adds challenge to making denture adhesives formulations. Some formulations have zinc to enhance adhesion on wet skin despite knowing the health hazards. Inspired by mussel foot proteins’ catechol unit’s strong underwater adhesion, nine catechol-containing copolymers (P1A-P3C) were synthesized by free radical polymerization of 3,4-dimethoxystyrene (3,4- DMS) with different styrene derivatives followed by deprotection. P1A-P3C were used to make Fn(P)-C-PBS denture adhesive formulations which had suitable shear stresses around ≥ 5 kPa satisfying ISO 10873. In-situ NMR studies of free radical polymerization of 3,4 - DMS and styrene derivatives allowed computation of their reactivity ratios showing all …

Syrian Refugee Women's Experiences With The Ontario Health Care System: A Critical Ethnography Study, Areej Al-Hamad

Electronic Thesis and Dissertation Repository

There has been growing interest in migration and refugee research; the vulnerability of Syrian refugee women and how they adapt to their host communities. However, there is limited evidence regarding the pre- and post-migration trauma and its impacts on the health of Syrian refugee women in the Canadian context. The purposes of this critical ethnography using intersectional perspectives were: (1) to explore and describe Syrian refugee women’s experiences and meanings of pre- and post-migration trauma and its impact on their health in the context of repeated displacement and migration from their homes and families; (2) to critically examine how the …

A Critical Review And Finite Element Study Of Structural Relaxation In Veneered 3y-Tzp Dental Structures, Prashant S. Shelar

Electronic Thesis and Dissertation Repository

Yttria stabilized Tetragonal Zirconia Polycrystal (3Y-TZP) materials veneered with porcelain are preferred for clinical practice due to their bio-functionality, biocompatibility, and affordability. However, these materials are often subjected to premature clinical failures due to combination of subsurface flaws and tensile stresses within porcelains. This work focuses on performing a critical literature review and evaluating veneer characteristics, i.e. structural relaxation, to form a suitable explanation for the development of subsurface stresses. User material subroutines, UEXPAN and UTRS are developed, validated and integrated in ABAQUS finite element solver. With the use of validated models, it is shown that faster cooling rates and …

Characterizing The Anxiolytic Potential And Synergistic Efficacy Of Cannabidiol And D-Limonene, Nathashi Jayawardena

Electronic Thesis and Dissertation Repository

Emerging evidence has elucidated the anxiolytic properties of the cannabis-derived phytochemicals cannabidiol (CBD) and d-limonene and the ‘Entourage Effect’ wherein, multiple components of cannabis synergize to produce stronger effects than their pure counterparts. However, no studies have yet explored this effect in combinations of CBD and limonene. Thus, the present thesis investigated the anxiolytic and synergistic potential of concurrently administered intra-nucleus accumbens shell CBD (1 ng/0.5 μl or 5 ng/0.5 μl) and inhaled limonene (200 μl or 2000 μl). Additionally, the role of the 5-HT1A receptor in mediating these effects was examined by co-application of the antagonist NAD299 and by …

Debt And Stress Amongst Orthodontic Residents, Timothy Renison

Electronic Thesis and Dissertation Repository

Background: The cost of education to become an orthodontist has increased significantly over recent years which has led to an increase in debt of graduating orthodontists.

Aim: This paper aims to assess whether debt amongst orthodontic residents in North America is associated with their stress levels, attitudes towards debt, financial literacy and mathematics anxiety.

Materials and Methods: Web-based software was used to fabricate a questionnaire, based on previously validated scales, in which respondents were asked questions regarding their debt levels, stress levels, attitudes towards debt, financial literacy and math anxiety.

Results: A total of 101 orthodontic residents completed the online …

In Vitro Analyses Of The Contributions Of The Hip Capsule To Joint Biomechanics, Emma Donnelly

Electronic Thesis and Dissertation Repository

Optimal management of the hip capsule during arthroscopic surgery has not been established. The impact of incisions made to the capsule during minimally invasive procedures on joint biomechanics, and whether repair provides any benefit, continue to be debated. The effectiveness of capsular repair to restore native kinematics may be insufficient. Therefore, a better understanding of joint behavior during various capsule conditions is needed. A new robotic system was used to analyze the effect of progressive capsulotomy incision and repairs on the behavior of a normal hip within range of motion (ROM) limits with respect to the intact joint. Complete repairs …

The Role Of Gsk3 Alpha And Beta In Embryonic Craniofacial Development, Harman Jassar

Electronic Thesis and Dissertation Repository

Background: The GSK-3 genes (Gsk3a and Gsk3b) have been known to affect many cellular processes and signaling pathways some of which are implicated in the growth and development of the craniofacial skeleton.

Aim: The purpose of this study was to assess the effect of chondrocyte-specific deletion of Gsk3a and Gsk3b on the size of the mandible and craniofacial skeleton in embryonic mice.

Materials & Methods: Mice were bred to generate cartilage-specific Gsk3a and Gsk3b KO mice. On embryonic day 18.5 (E18.5) the offspring were gathered by caesarian section. Whole mount skeletal staining was completed on the specimens using …

Guidance For Dental Treatment Of Patients With Disabilities During Covid-19 Pandemic, Eun Jung Kwak, Jieun Kim, Hiran Perinpanayagam, Kee Yeon Kum

Dentistry Publications

People with disabilities are challenged managing their oral hygiene and more often burdened with oral diseases. They often require immediate dental treatment for severe pain and greater precautions are needed to cope with COVID-19. The potential for COVID-19 infection can be relatively high in patients with disabilities due to concomitant systemic diseases, unique individual circumstances, relationship with caregivers and the living conditions of long-term care facilities, which make them vulnerable to the virus. For behavior management, dental treatment is often provided under general anesthesia with meticulous preoperative evaluation and the use of high-quality viral filters. In response to COVID-19, additional …

Disease-Related Cortical Thinning In Presymptomatic Granulin Mutation Carriers, Sergi Borrego-Écija, Roser Sala-Llonch, John Van Swieten, Barbara Borroni, Fermín Moreno, Mario Masellis, Carmela Tartaglia, Caroline Graff, Daniela Galimberti, Robert Laforce, James B. Rowe, Elizabeth Finger, Rik Vandenberghe, Fabrizio Tagliavini, Alexandre De Mendonça, Isabel Santana, Matthis Synofzik, Simon Ducharme, Johannes Levin, Adrian Danek, Alex Gerhard, Markus Otto, Chris Butler, Giovanni Frisoni, Sandro Sorbi, Carolin Heller, Martina Bocchetta, David M. Cash, Rhian S. Convery, Katrina M. Moore, Jonathan D. Rohrer, Raquel Sanchez-Valle

Medical Biophysics Publications

Mutations in the granulin gene (GRN) cause familial frontotemporal dementia. Understanding the structural brain changes in presymptomatic GRN carriers would enforce the use of neuroimaging biomarkers for early diagnosis and monitoring. We studied 100 presymptomatic GRN mutation carriers and 94 noncarriers from the Genetic Frontotemporal dementia initiative (GENFI), with MRI structural images. We analyzed 3T MRI structural images using the FreeSurfer pipeline to calculate the whole brain cortical thickness (CTh) for each subject. We also perform a vertex-wise general linear model to assess differences between groups in the relationship between CTh and diverse covariables as gender, age, the estimated years …