Digital Commons Network^™

A Trial Of Wound Irrigation In The Initial Management Of Open Fracture Wounds, Mohit Bhandari, Kyle J. Jeray, Brad A. Petrisor, P. J. Devereaux, Diane Heels-Ansdell, Emil H. Schemitsch, Jeff Anglen, Gregory J. Della Rocca, Clifford Jones, Hans Kreder, Susan Liew, Paula Mckay, Steven Papp, Parag Sancheti, Sheila Sprague, Trevor B. Stone, Xin Sun, Stephanie L. Tanner, Paul Tornetta, Ted Tufescu, Stephen Walter, Gordon H. Guyatt

Bone and Joint Institute

Copyright © 2015 Massachusetts Medical Society. BACKGROUND The management of open fractures requires wound irrigation and dridement to remove contaminants, but the effectiveness of various pressures and solutions for irrigation remains controversial. We investigated the effects of castile soap versus normal saline irrigation delivered by means of high, low, or very low irrigation pressure. METHODS In this study with a 2-by-3 factorial design, conducted at 41 clinical centers, we randomly assigned patients who had an open fracture of an extremity to undergo irrigation with one of three irrigation pressures (high pressure [>20 psi], low pressure [5 to 10 psi], …

Phase Ii Clinical Trial Of Concurrent Neoadjuvant Chemotherapy With Radiotherapy In Locally Advanced Breast Cancer, Muriel Brackstone

Electronic Thesis and Dissertation Repository

Locally advanced breast cancer (LABC) represents 15% of all non-metastatic breast cancers, with an overall poor prognosis, despite current guidelines that recommend neoadjuvant chemotherapy followed by surgery and adjuvant radiation. Therefore, a novel treatment paradigm using concurrent neoadjuvant chemoradiotherapy was proposed. A clinical trial was designed, where 32 LABC patients were treated with q3 weekly 5-fluorouracil, epirubicin and cyclophosphamide for three cycles, followed by weekly docetaxel for 9 weeks with concurrent regional radiation (45+5.4Gy) for the first 6 weeks. Patients subsequently underwent modified radical mastectomies. Pathological complete responses (pCR) and 3 year overall survival rates were compared to a matched …

Evidence Reversal: When New Evidence Contradicts Established Practices, Desiree S. Sutton

Electronic Thesis and Dissertation Repository

Evidence reversal occurs when new evidence contradicts established practices. The first component of this thesis is an umbrella overview of investigations – reviews and collections of studies – into evidence reversal to gather concepts and methods that we identified as useful to lay a foundation for a standardized ‘theory of reversal.’ The foundation of this review enables the construction of a framework that will provide structure to this field, as no formal organization currently exists. The next component builds upon this foundation and proposes a framework for evidence reversal and its related concepts. The second review takes this framework …

Exercise Identity: Origins, Applications, And Future Utility, Vincent L. Liardi

Electronic Thesis and Dissertation Repository

It has been determined that exercise identity (EI) is a key component of the self-concept and is a strong determinant of exercise behaviours. The primary purpose of study 1 was to examine EI’s relationship with three key self-presentational variables: self-presentational efficacy (SPE), social physique anxiety (SPA), and impression motivation (IM). Specifically, we looked at how EI contributed uniquely to predicting exercise behaviour over and above these self-presentational concerns. The analyses demonstrated that EI is positively correlated with SPE and unrelated to SPA in both genders. Further analyses revealed that EI contributes a significant amount of variance towards exercise behaviour over …

Smoking And Exercise: Mechanisms And Effects During Simulated And Genuine Quit Attempts, Stefanie De Jesus

Electronic Thesis and Dissertation Repository

Cigarette smoking is a leading agent for premature morbidity and mortality among the global community. Most individuals surrender to tobacco use disorder due to the inability to cope with cravings and withdrawal symptoms. Exercise appears to provide acute relief. Currently, it is unclear how exercise attenuates these reductions. Furthermore, the available evidence has focused on acute outcomes besides smoking behaviour and is limited to simulated quit attempts. Three experimental studies were designed to address these outstanding issues. Not surprisingly, a bout of moderate intensity exercise was found in study 1 (chapter 2) to reduce cravings associated with a temporary period …

Mothers Experiencing Homelessness: Social Exclusion, Resistance, And Health, Sarah Benbow

Electronic Thesis and Dissertation Repository

Background and Purpose: Mothers experiencing homelessness in Canada are faced with unique challenges in achieving health. The purpose of this two-phase study was to critically examine the socio-political context, health needs, exclusionary and inclusionary forces, and strategies of resistance demonstrated by mothers experiencing homelessness.

Methodology: This study falls under the critical paradigm informed by the theoretical perspective of intersectionality. Methodologies employed included critical narrative and critical discourse analysis. Data were collected at various homeless shelters and programs that provide services for women and mothers who are homeless in Southern Ontario. A purposive sample of women experiencing homelessness, and service …

Physical Exertion As A Risk Factor For Ventricular Arrhythmia: A Prospective Cohort Study, Harpreet S. Chahal

Electronic Thesis and Dissertation Repository

Episodes of physical exertion are associated with an immediately higher risk of cardiovascular events while physical activity over the long-term is cardioprotective. To assess the transient and long-term risk of ventricular arrhythmia (VA), we conducted a nested case-crossover study within a prospective cohort of 97 patients with implantable cardioverter-defibrillators (ICD). Within an hour of episodes of exertion, the risk of VA was 5.3 (95% CI 2.7 – 10.6) times greater compared to periods of rest. The association was higher among patients with aerobic fitness below the median (RR[relative risk]=17.5, 95% 5.2 – 58.5) than for patients with aerobic fitness above …

Intracellular Trafficking Governs The Processing Of The Amyloid Precursor Protein And The Secretion Of Beta-Amyloid, Joshua Hoi Ki Tam

Electronic Thesis and Dissertation Repository

One of the hallmarks of Alzheimer’s disease (AD) is the pathological accumulation of β-amyloid (Aβ) in the brains of AD patients. Oligomeric and fibrillar aggregates of Aβ have been shown to be neurotoxic to neurons and hippocampal slices. Therefore, limiting Aβ production is an important area of research in order to delay or stop AD progression. Aβ is produced by amyloidogenic cleavage of amyloid precursor protein (APP). Amyloidogenic cleavage requires ectodomain removal by β-secretase and intramembrane γ-cleavage by γ-secretase to release Aβ products ranging from 38-43 residues. Work from our lab has shown that APP and γ-secretase are resident proteins …

"A Family Doctor Can Do That!" Is There A Role For A Formalized Referral Network For Office Procedures In Family Practices Of Newfoundland And Labrador?, Annabeth J. Loveys

Electronic Thesis and Dissertation Repository

Office procedures are an important part of the comprehensive care package provided by family physicians. Every family physician cannot feasibly perform every office procedure. A cadre of family physicians drawing upon each other’s procedural skills has the potential to improve patient care and enhance physician satisfaction. A mixed methods approach was used to explore potential clinical and educational roles of a formalized referral networkfor office procedures in Newfoundland and Labrador, Canada. In a quantitative study, using a self-administered survey, family physicians identified that while there are procedures being performed in family practice, there is a discrepancy between the demand for, …

Trends In Psychotropic Dispensing Among Older Adults With Dementia Living In Long-Term Care Facilities: 2004-2013., Akshya Vasudev, Salimah Z Shariff, Kuan Liu, Amer M Burhan, Nathan Herrmann, Sean Leonard, Muhammad Mamdani

Psychiatry Publications

OBJECTIVE: Guidelines worldwide have cautioned against the use of antipsychotics as first-line agents to treat neuropsychiatric symptoms of dementia. We aimed to investigate the changes over time in the dispensing of antipsychotics and other psychotropics among older adults with dementia living in long-term care facilities.

METHODS: We used drug claims data from Ontario, Canada, to calculate quarterly rates of prescription dispensing of six psychotropic drug classes among all elderly (≥65 years of age) long-term care residents with dementia from January 1, 2004, to March 31, 2013. Psychotropic drugs were classified into the following categories: atypical and conventional antipsychotics, non-sedative and …

An Intra-Bone Axial Load Transducer: Development And Validation In An In-Vitro Radius Model, Nikolas K. Knowles, Michael Gladwell, Louis M. Ferreira

Surgery Publications

Background

Accurate measurement of forces through the proximal radius can assess the effects of some surgical procedures on radioulnar load sharing, but is difficult to achieve given the redundant loading nature of the musculoskeletal system. Previously reported devices have relied on indirect measurements that may alter articular joint location and function. An axial load transducer interposed in the diaphysis of the radius may accurately quantify unknown axial loads of the proximal radius, and maintain articular location.

Methods

An in-vitro radius model was developed by interposing an axial load transducer in the diaphysis of the proximal radius. Static loads of 20, …

Functional Outcomes Of Acutely Infected Knee Arthroplasty: A Comparison Of Different Surgical Treatment Options, Ivan Dzaja, James Howard, Lyndsay Somerville, Brent Lanting

Bone and Joint Institute

© 2015 8872147 Canada Inc. Background: An infected total knee arthroplasty (TKA) can be treated with irrigation and débridement with polyethylene exchange (IDPE) or a 2-staged revision (2SR). Although research has examined infection eradication rates of both treatments, patient outcomes have not been reported. We examined patient-reported outcomes following treatment compared with matched, noninfected controls. Methods: We retrospectively identified patients with infected TKAs who had undergone the index procedure between May 1991 and November 2011. Patient-reported outcomes included the 12-item Short Form Health Survey, Western Ontario and McMaster Universities Arthritis Index, and Knee Society Scores as well as range of …

The Child And Adolescent Scale Of Environment (Case): Further Validation With Youth Who Have Chronic Conditions, Gary Bedell, Janette Mcdougal

Occupational Therapy Publications

Objective: To further validate the Child and Adolescent Scale of Environment (CASE).

Methods: Baseline data (n = 430) were analyzed from a longitudinal study on quality of life for youth with chronic conditions ages 11–17 in Ontario, Canada. Internal consistency and structure, and convergent and discriminant validity were examined via Cronbach’s alpha (α), exploratory factor analyses, correlation analyses and ANOVA.

Results: The CASE had high internal consistency (α = 0.89). A three-factor solution was produced with 55% variance explained: (1) Community/Home Resources, (2) School Resources and (3) Physical Design/Access). CASE total and factor …

Methods And Considerations For The Analysis And Standardization Of Assessing Muscle Sympathetic Nerve Activity In Humans, Daniel W. White, J. Kevin Shoemaker, Peter B. Raven

Bone and Joint Institute

© 2015 Elsevier B.V.. The technique of microneurography and the assessment of muscle sympathetic nerve activity (MSNA) are used in laboratories throughout the world. The variables used to describe MSNA, and the criteria by which these variables are quantified from the integrated neurogram, vary among studies and laboratories and, therefore, can become confusing to those starting to learn the technique. Therefore, the purpose of this educational review is to discuss guidelines and standards for the assessment of sympathetic nervous activity through the collection and analysis of MSNA. This review will reiterate common practices in the collection of MSNA, but will …

Greater Magnocellular Saccadic Suppression In High Versus Low Autistic Tendency Suggests A Causal Path To Local Perceptual Style., David P Crewther, Daniel Crewther, Stephanie Bevan, Melvyn A Goodale, Sheila G Crewther

Brain and Mind Institute Researchers' Publications

Saccadic suppression-the reduction of visual sensitivity during rapid eye movements-has previously been proposed to reflect a specific suppression of the magnocellular visual system, with the initial neural site of that suppression at or prior to afferent visual information reaching striate cortex. Dysfunction in the magnocellular visual pathway has also been associated with perceptual and physiological anomalies in individuals with autism spectrum disorder or high autistic tendency, leading us to question whether saccadic suppression is altered in the broader autism phenotype. Here we show that individuals with high autistic tendency show greater saccadic suppression of low versus high spatial frequency gratings …

Pulmonary Imaging To Better Understand Asthma, Sarah Svenningsen

Electronic Thesis and Dissertation Repository

Asthma is characterized using the spirometry measurement of the forced expiratory volume in one second (FEV₁). Simple and inexpensive, FEV₁ provides a global estimate of lung function but this metric cannot regionally identify airways responsible for airflow limitation, asthma symptoms or control. Work that brought about an understanding that airway abnormalities are heterogeneously distributed within the lung in asthma patients has motivated the development of pulmonary imaging approaches, such as hyperpolarized helium-3 (³He) and xenon-129 (¹²⁹Xe) magnetic resonance imaging (MRI). These methods provide a way to visualize and quantify lung regions accessed by …

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

Electronic Thesis and Dissertation Repository

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 …

Thermosensitive Polymer-Grafted Iron Oxide Nanoparticles Studied By In Situ Dynamic Light Backscattering Under Magnetic Hyperthermia, Gauvin Hemery, Elisabeth Garanger, Sébastien Lecommandoux, Andrew D. Wong, Elizabeth R. Gillies, Boris Pedrono, Thomas Bayle, David Jacob, Olivier Sandre

Bone and Joint Institute

© 2015 IOP Publishing Ltd. Thermometry at the nanoscale is an emerging area fostered by intensive research on nanoparticles (NPs) that are capable of converting electromagnetic waves into heat. Recent results suggest that stationary gradients can be maintained between the surface of NPs and the bulk solvent, a phenomenon sometimes referred to as 'cold hyperthermia'. However, the measurement of such highly localized temperatures is particularly challenging. We describe here a new approach to probing the temperature at the surface of iron oxide NPs and enhancing the understanding of this phenomenon. This approach involves the grafting of thermosensitive polymer chains to …

The Transient Receptor Potential Melastatin 2 (Trpm2) Channel Contributes To Beta-Amyloid Oligomer-Related Neurotoxicity And Memory Impairment, Valeriy G. Ostapchenko, Megan Chen, Monica S. Guzman, Yu-Feng Xie, Natalie Lavine, Jue Fan, Flavio H. Beraldo, Amanda C. Martyn, Jillian C. Belrose, Yasuo Mori, John F. Macdonald, Vania F. Prado, Marco A. M. Prado, Michael F. Jackson

Anatomy and Cell Biology Publications

In Alzheimer's disease, accumulation of soluble oligomers of beta-amyloid peptide is known to be highly toxic, causing disturbances in synaptic activity and neuronal death. Multiple studies relate these effects to increased oxidative stress and aberrant activity of calcium-permeable cation channels leading to calcium imbalance. The transient receptor potential melastatin 2 (TRPM2) channel, a Ca2+-permeable nonselective cation channel activated by oxidative stress, has been implicated in neurodegenerative diseases, and more recently in amyloid-induced toxicity. Here we show that the function of TRPM2 is augmented by treatment of cultured neurons with beta-amyloid oligomers. Aged APP/PS1 Alzheimer's mouse model showed increased levels of …

Survival Outcomes And Treatment Utilization Among Patients With Known And Unknown Primary Tumours In Ontario., Chong Sung Kim

Electronic Thesis and Dissertation Repository

I identify two cohorts of cancer patients with known and unknown primary tumours. Cancer of unknown primary (CUP) is defined by the presence of pathologically identified metastatic disease without clinical or radiological evidence of a primary tumour. Using the Ontario Cancer Registry, Same Day Surgery/Discharge Abstract Database and Ontario Health Insurance Plan, a novel linkage strategy was developed to cross-validate diagnoses. I found CUP patients represent a significant portion of all metastatic cancers. CUP patients with histological confirmed disease, squamous cell histology, or metastases localized to nodal regions had significantly better survival than other CUP patients. Knowledge of the primary …

The Development And Validation Of A Molecular Imaging Probe Targeted To Cathepsin D For The In-Vivo Detection Of Alzheimer Disease, Jonatan Snir

Electronic Thesis and Dissertation Repository

Background: Currently there is no widely accepted test to diagnose AD. The involvement of the lysosomal system in Alzheimer’s disease (AD) progression provides an opportunity to develop associated biomarkers. The lysosomal enzyme Cathepsin D (CatD) has been shown to be over-expressed in the AD brain before clinical onset. We have developed a dual modality contrast agent (CA) to detect CatD activity which consists of an HIV-1 Tat Cell Penetrating Peptide (CPP) conjugated to a CatD cleavage sequence and two imaging moieties consisting of a fluorescently- tagged probe and a DOTA cage for chelating Gallium-68. The purpose of this work was …

Renal Oncocytosis In A Pediatric Patient: Case Report And Review Of The Literature, Stacey Speer, Daniele Wiseman, Madeleine Moussa, Andreana Bütter

Surgery Publications

Renal oncocytosis is a rare condition in which the kidney develops numerous oncocytomas. We present a case of a 12-year-old female who presented with right-sided flank pain of one-year duration. Imaging revealed several masses in the right kidney. Tissue biopsy confirmed multiple benign oncocytomas. Due to the presence of multiple oncocytomas throughout the kidney, a radical nephrectomy was performed. Given the rarity of this condition, as well as its known association with von Hippel-Lindau disease and Birt-Hogg-Dube syndrome, genetic investigations were pursued but failed to identify any abnormalities. This patient remains well and disease free six years after surgery. A …

Rapid Fecal Calprotectin Testing To Assess For Endoscopic Disease Activity In Inflammatory Bowel Disease: A Diagnostic Cohort Study, Lukasz Kwapisz, Mahmoud Mosli, Nilesh Chande, Brian Yan, Melanie Beaton, Jessica Micsko, Pauline W. Mennill, William Barnett, Kevin Bax, Terry Ponich, John Howard, Anthony Tirolese, Robert Lannigan, James Gregor

Paediatrics Publications

Background and Aim: With increasing numbers of patients diagnosed with inflammatory bowel disease (IBD), it is important to identify noninvasive methods of detecting disease activity. The aim of this study is to examine the diagnostic accuracy of fecal rapid calprotectin (FC) testing in the detection of endoscopically active IBD. Patients and Methods: All consecutive patients presenting to outpatient clinics with lower gastrointestinal symptoms were prospectively recruited. Patients provided FC samples. Sensitivity (Sn), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV) for FC were calculated. Receiver-operator characteristics (ROC) curve was used to identify the ideal FC cutoff that …

Identification And Survival Outcomes Of A Cohort Of Patients With Cancer Of Unknown Primary In Ontario, Canada., Chong S Kim, Malek B Hannouf, Sisira Sarma, George B Rodrigues, Peter K Rogan, Salaheddin M Mahmud, Eric Winquist, Muriel Brackstone, Gregory S Zaric

Epidemiology and Biostatistics Publications

BACKGROUND: Cancer of unknown primary origin (CUP) is defined by the presence of pathologically identified metastatic disease without clinical or radiological evidence of a primary tumour. Our objective was to identify incident cases of CUP in Ontario, Canada, and determine the influence of histology and sites of metastases on overall survival (OS).

MATERIAL AND METHODS: We used the Ontario Cancer Registry (OCR) and the Same-Day Surgery and Discharge Abstract Database (SDS/DAD) to identify patients diagnosed with CUP in Ontario between 1 January 2000, and 31 December 2005. Patient diagnostic information, including histology and survival data, was obtained from the OCR. …

Behavioral, Perceptual, And Neural Alterations In Sensory And Multisensory Function In Autism Spectrum Disorder., Sarah H Baum, Ryan A Stevenson, Mark T Wallace

Brain and Mind Institute Researchers' Publications

Although sensory processing challenges have been noted since the first clinical descriptions of autism, it has taken until the release of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013 for sensory problems to be included as part of the core symptoms of autism spectrum disorder (ASD) in the diagnostic profile. Because sensory information forms the building blocks for higher-order social and cognitive functions, we argue that sensory processing is not only an additional piece of the puzzle, but rather a critical cornerstone for characterizing and understanding ASD. In this review we discuss what …

Dual Optimization Method Of Radiofrequency And Quasistatic Field Simulations For Reduction Of Eddy Currents Generated On 7t Radiofrequency Coil Shielding., Yujuan Zhao, Tiejun Zhao, Shailesh B Raval, Narayanan Krishnamurthy, Hai Zheng, Chad T Harris, William B Handler, Blaine A Chronik, Tamer S Ibrahim

Brain and Mind Institute Researchers' Publications

PURPOSE: To optimize the design of radiofrequency (RF) shielding of transmit coils at 7T and reduce eddy currents generated on the RF shielding when imaging with rapid gradient waveforms.

METHODS: One set of a four-element, 2 × 2 Tic-Tac-Toe head coil structure was selected and constructed to study eddy currents on the RF coil shielding. The generated eddy currents were quantitatively studied in the time and frequency domains. The RF characteristics were studied using the finite difference time domain method. Five different kinds of RF shielding were tested on a 7T MRI scanner with phantoms and in vivo human subjects. …

A Review Of Transcranial Magnetic Stimulation And Multimodal Neuroimaging To Characterize Post-Stroke Neuroplasticity, Angela M. Auriat, Jason L. Neva, Sue Peters, Lara A. Boyd

Physical Therapy Publications

Following stroke, the brain undergoes various stages of recovery where the central nervous system can reorganize neural circuitry (neuroplasticity) both spontaneously and with the aid of behavioral rehabilitation and non-invasive brain stimulation. Multiple neuroimaging techniques can characterize common structural and functional stroke-related deficits, and importantly, help predict recovery of function. Diffusion tensor imaging (DTI) typically reveals increased overall diffusivity throughout the brain following stroke, and is capable of indexing the extent of white matter damage. Magnetic resonance spectroscopy (MRS) provides an index of metabolic changes in surviving neural tissue after stroke, serving as a marker of brain function. The neural …

Evaluation And Treatment Of Lower Extremity Wounds In A Vascular Surgery Patient Population, Christine Anne Murphy

Electronic Thesis and Dissertation Repository

Purpose

To determine in a population with lower extremity wounds associated with vasculopathy if: (1) previously proposed clinical signs of infection are valid indicators of wound infection; (2) low frequency (22.5 kHz) contact ultrasound debridement (LFCUD) is well tolerated and feasible to apply in a nurse-led vascular wound clinic; (3) healing outcomes are improved for patients receiving LFCUD in comparison to patients receiving usual care (UC).

Methods

A total of 80 patients were in the study. First, a pilot group of ten patients were followed to determine tolerability, feasibility and wound response of 4 weekly LFCUD treatments. Then 70 patients …

Differential Modification Of Cortical And Thalamic Projections To Cat Primary Auditory Cortex Following Early- And Late-Onset Deafness., Nicole Chabot, Blake E Butler, Stephen G Lomber

Brain and Mind Institute Researchers' Publications

Following sensory deprivation, primary somatosensory and visual cortices undergo crossmodal plasticity, which subserves the remaining modalities. However, controversy remains regarding the neuroplastic potential of primary auditory cortex (A1). To examine this, we identified cortical and thalamic projections to A1 in hearing cats and those with early- and late-onset deafness. Following early deafness, inputs from second auditory cortex (A2) are amplified, whereas the number originating in the dorsal zone (DZ) decreases. In addition, inputs from the dorsal medial geniculate nucleus (dMGN) increase, whereas those from the ventral division (vMGN) are reduced. In late-deaf cats, projections from the anterior auditory field (AAF) …

Exploring The Daily Lives Of People On Methadone Maintenance Treatment: An Occupational Perspective, Katrina Warren

Electronic Thesis and Dissertation Repository

A study was undertaken with five people on Methadone Maintenance Treatment (MMT) within London, Ontario. The objectives were to better understand the experiences and daily routines of people on MMT through in-depth exploration of their everyday occupations and the ongoing challenges and barriers they face to accessing treatment. This research employed a qualitative intrinsic case study methodology (Stake, 1995). Using an occupational perspective informed by a framework for occupational justice (Stadnyk et al., 2010), findings are presented according to four themes highlighting key aspects of the participants' experiences: a) a ‘descent into chaos’, b) ‘MMT as a bridge’ to recovery …