Medicine and Health Sciences Commons^™

The Loss Of Atrx Increases Susceptibility To Pancreatic Injury And Oncogenic Kras In Female But Not Male Mice., Claire C Young, Ryan M Baker, Christopher J Howlett, Todd Hryciw, Joshua E Herman, Douglas Higgs, Richard Gibbons, Howard Crawford, Arthur Brown, Christopher L Pin

Paediatrics Publications

Background

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in North America, accounting for >30,000 deaths annually. Although somatic activating mutations in KRAS appear in 97% of PDAC patients, additional factors are required to initiate PDAC. Because mutations in genes encoding chromatin remodelling proteins have been implicated in KRAS-mediated PDAC, we investigated whether loss of chromatin remodeler ɑ-thalassemia, mental-retardation, X-linked (ATRX) affects oncogenic KRAS’s ability to promote PDAC. ATRX affects DNA replication, repair, and gene expression and is implicated in other cancers including glioblastomas and pancreatic neuroendocrine tumors. The hypothesis was that deletion of Atrx …

Linked Mri Signatures Of The Brain's Acute And Persistent Response To Concussion In Female Varsity Rugby Players., Kathryn Y Manning, Alberto Llera, Gregory A Dekaban, Robert Bartha, Christy Barreira, Arthur Brown, Lisa Fischer, Tatiana Jevremovic, Kevin Blackney, Timothy J Doherty, Douglas D Fraser, Jeff Holmes, Christian F Beckmann, Ravi S Menon

Paediatrics Publications

Acute brain changes are expected after concussion, yet there is growing evidence of persistent abnormalities well beyond clinical recovery and clearance to return to play. Multiparametric MRI is a powerful approach to non-invasively study structure-function relationships in the brain, however it remains challenging to interpret the complex and heterogeneous cascade of brain changes that manifest after concussion. Emerging conjunctive, data-driven analysis approaches like linked independent component analysis can integrate structural and functional imaging data to produce linked components that describe the shared inter-subject variance across images. These linked components not only offer the potential of a more comprehensive understanding of …

Comprehensive Evaluation Of Right Heart Performance And Pulmonary Hemodynamics In Neonatal Pulmonary Hypertension: Evaluation Of Cardiopulmonary Performance In Neonatal Pulmonary Hypertension, Soume Bhattacharya, Shawn Sen, Philip T. Levy, Danielle R. Rios

Paediatrics Publications

Purpose of review: Pulmonary hypertension is characterized by an elevation of pulmonary artery pressures and prolonged exposure of the right ventricle to high afterload that collectively contribute to morbidity and mortality in both the term and preterm infants. This review summarizes the pathogenesis, etiologies, and hemodynamic profiles of the conditions that result in pulmonary hypertension in neonates. We explore the application of echocardiographic techniques for the assessment of right ventricular performance and pulmonary hemodynamics that enhance and guide the diagnosis and management strategies in neonates. Recent findings: Clinical assessments based on the determinants of mean pulmonary artery pressures (pulmonary vascular …

Surgical Technique For Developing A Rabbit Model Of Congenital Diaphragmatic Hernia And Tracheal Occlusion, M. Mudri, S. A. Smith, C. Vander Tuin, J. Davidson, T. R.H. Regnault, A. Bütter

Paediatrics Publications

The surgical model of congenital diaphragmatic hernia (CDH) has been utilized in exploring treatments and innovative therapies, such as tracheal occlusion (TO). The rabbit is an excellent surgical model compared to others due to lower cost, ease of care, short gestational period, and large litter size. This model is also ideal in studying lung hypoplasia of CDH because rabbit lung development is most similar to humans as alveolarization begins prior to birth and continues post-natally. However, the surgical technique in creating a rabbit model of CDH is quite difficult and information is lacking on how to establish this model. Therefore, …

Direct Genetics Referral Pathway For High-Grade Serous Ovarian Cancer Patients: The "Opt-Out" Process, Jacob Mcgee, Teresa M. Peart, Norine Foley, Monique Bertrand, Michel Prefontaine, Akira Sugimoto, Helen Ettler, Stephen Welch, Karen Panabaker

Obstetrics & Gynaecology Publications

Purpose. In order to meet a clinical need for better pathways to access genetic testing for ovarian cancer patients, we implemented and reviewed an opt-out referral process for genetic consultation whereby a referral is automatically sent to genetics following a pathological diagnosis of HGSC. Methods. Following implementation of the opt-out referral process, each month a list of new cases of HGSC was generated from the synoptic pathology report and forwarded directly to the Cancer Genetics clinic. Using an advanced directive, patients were automatically referred for genetic counselling two months after surgery. If the patient declined genetic counselling (opted-out) after discussion …

White Matter Biomarkers Associated With Motor Change In Individuals With Stroke: A Continuous Theta Burst Stimulation Study, K P Wadden, Sue Peters, M R Borich, J L Neva, K S Hayward, C S Mang, N J Snow, K E Brown, T S Woodward, S K Meehan, L A Boyd

Physical Therapy Publications

Continuous theta burst stimulation (cTBS) is a form of noninvasive repetitive brain stimulation that, when delivered over the contralesional hemisphere, can influence the excitability of the ipsilesional hemisphere in individuals with stroke. cTBS applied prior to skilled motor practice interventions may augment motor learning; however, there is a high degree of variability in individual response to this intervention. The main objective of the present study was to assess white matter biomarkers of response to cTBS paired with skilled motor practice in individuals with chronic stroke. We tested the effects of stimulation of the contralesional hemisphere at the site of the …

The Effects Of Methylphenidate (Ritalin) On The Neurophysiology Of The Monkey Caudal Prefrontal Cortex, Sébastien Tremblay, Florian Pieper, Adam Sachs, Ridha Joober, Julio Martinez-Trujillo

Physiology and Pharmacology Publications

© 2019 Tremblay et al. Methylphenidate (MPH), commonly known as Ritalin, is the most widely prescribed drug worldwide to treat patients with attention deficit disorders. Although MPH is thought to modulate catecholamine neurotransmission in the brain, it remains unclear how these neurochemical effects influence neuronal activity and lead to attentional enhancements. Studies in rodents overwhelmingly point to the lateral prefrontal cortex (LPFC) as a main site of action of MPH. To understand the mechanism of action of MPH in a primate brain, we recorded the responses of neuronal populations using chronic multielectrode arrays implanted in the caudal LPFC of two …

Perceptions On Competence By Design In Urology, Peter Wang, Ernest Chan, Adam Forster, Jennifer Vergel De Dios, Alp Sener, Sumit Dave, Saad Chahine

Paediatrics Publications

Introduction: The Royal College of Physicians and Surgeons of Canada has begun implementing Competence by Design (CBD). However, it is unclear how much urology trainees and faculty know about CBD, their attitudes towards this change, and their willingness to embrace and participate in this new model of training. Methods: This cross-sectional study was conducted through an online survey, which was administered to all trainees and faculty at Canadian urology programs prior to the implementation of CBD. The final survey consisted of eight demographic questions, 17 five-point Likert items, one visual analog scale question, 11 multiple-choice questions, and two open-ended questions. …

Reply To: Calcium/Citrate Ratio And Risk Of Kidney Stone, Misan Lee, Carmen Inés Rodriguez Cuellar, Ravneet Nagra, Peter Zhan Tao Wang, Vipin Bhayana, Guido Filler

Paediatrics Publications

No abstract provided.

Does The Urinary Calcium/Citrate Ratio Add To The Diagnostic Workup Of Children At Risk Of Kidney Stones? A Cross-Sectional Study, Misan Lee, Carmen Inés Rodriguez Cuellar, Ravneet Nagra, Zhan Tao Peter Wang, Vipin Bhayana, Guido Filler

Paediatrics Publications

The purpose of the study was to evaluate urinary citrate/creatinine (U Ci /U Cr ) and urinary calcium/citrate (U Ca /U Ci ) ratios for distinguishing stone formers (SF) from non-stone formers (NSF) in an at-risk population. This was a retrospective study that included all pediatric patients who underwent urinary citrate testing from April 2017 to March 2018. The urinary levels of citrate, calcium, sodium, potassium, creatinine, oxalate, urate, pH, and specific gravity (SG) were measured in our clinical laboratory. Diagnosis of kidney stones was obtained through chart review. A total of 97 patients were included (46 NSF and 51 …

Maternal Undernourishment In Guinea Pigs Leads To Fetal Growth Restriction With Increased Hypoxic Cells And Oxidative Stress In The Brain., Yohei Maki, Karen Nygard, Robert R Hammond, Timothy Regnault, Bryan S Richardson

Paediatrics Publications

BACKGROUND: We determined whether maternal nutrient restriction (MNR) in guinea pigs leading to fetal growth restriction (FGR) impacts markers for brain hypoxia and oxidative stress.

METHODS: Guinea pigs were fed ad libitum (control) or 70% of the control diet before pregnancy, switching to 90% at mid-pregnancy (MNR). Near term, hypoxyprobe-1 (HP-1) was injected into pregnant sows. Fetuses were then necropsied and brain tissues were processed for HP-1 (hypoxia marker) and 4HNE, 8-OHdG, and 3-nitrotyrosine (oxidative stress markers) immunoreactivity (IR).

RESULTS: FGR-MNR fetal and brain weights were decreased 38 and 12%, respectively, with brain/fetal weights thereby increased 45% as a measure …

Engaging The Occupational Imagination: Meeting In Diversity, Debbie Rudman

Occupational Therapy Publications

This article provides a reflection on the 2017 Occupational Science Europe conference through a critical occupational science lens. I first provide a key synopsis of lines of arguments forwarded in a keynote talk I delivered at this conference, titled ‘Embracing a critical turn in occupational science: Contributions and future possibilities’. I then draw upon one of the key directions forwarded in this talk as a means to further enact a transformative agenda through critical occupational science to reflect on how ‘meeting in diversity’ fostered critical alertness. In particular, the strategy of ‘meeting in diversity’ with occupation as a common ground …

Motivational Interviewing With Families In The Home Environment, Carley O'Kane, Jennifer Irwin, Don Morrow, Lisa Tang, Samantha Wong, Andrea Buchholz, David Ma, Jess Haines

Health Studies Publications

Objective: This study explored the feasibility and acceptability of using Motivational Interviewing (MI) in the home setting with families of preschoolers. Methods: Using mixed-methods pilot data from an MI-based obesity prevention intervention delivered via home visits by health educators (HEs) with 44 families (n = 17 four home visit group; n = 14 two home visit group), we examined: 1) fidelity of MI adherence by HEs; 2) parents’ perceptions of the intervention; and 3) HEs insights pertaining to the intervention’s delivery. Results: Multiple measures of MI fidelity were deemed to exceed defined proficiency levels. Ninety-three percent of families reported being …

Research Snapshot: A Preliminary Randomized Controlled Evaluation Of A Universal Healthy Relationships Promotion Program For Youth, Centre For School Mental Health

Research Snapshots

This study evaluated the Health Relationships Plus program (HRP) with a group of Canadian youth. HRP aims to promote positive mental health and reduce bullying and substance misuse. Researchers found that HRP participation significantly reduced the odds of physical bullying victimization at one-year follow-up compared to the control group.

Hyperpolarized 3he Mri Ventilatory Apparent Diffusion Coefficient Of Alpha-1 Antitrypsin, Andrew Westcott, Dante P I Capaldi, Alexei Ouriadov, David G Mccormack, Grace Parraga

Medical Biophysics Publications

Alpha-1 antitrypsin deficiency (AATD) leads to disabling chronic obstructive pulmonary disease (COPD). Current therapy aimed at slowing lung disease progression includes exogenous alpha-1 antitrypsin augmentation therapy, but there are few potential new treatments under development. Currently used measurements of AATD-related emphysema include the forced expiratory volume in 1 second (FEV1) and the diffusing capacity of carbon monoxide (DLCO); both are relatively insensitive to therapy, although computed tomography (CT) lung density measurements have been shown to worsen more slowly in treated patients.

Deep Learning Approach For Automatic Out-Of-Plane Needle Localisation For Semi-Automatic Ultrasound Probe Calibration, Leah A. Groves, Blake Vanberlo, Terry M. Peters, Elvis C.S. Chen

Medical Biophysics Publications

© 2019 Institution of Engineering and Technology. All rights reserved. The authors present a deep learning algorithm for the automatic centroid localisation of out-of-plane US needle reflections to produce a semi-automatic ultrasound (US) probe calibration algorithm. A convolutional neural network was trained on a dataset of 3825 images at a 6 cm imaging depth to predict the position of the centroid of a needle reflection. Applying the automatic centroid localisation algorithm to a test set of 614 annotated images produced a root mean squared error of 0.62 and 0.74 mm (6.08 and 7.62 pixels) in the axial and lateral directions, …

White Matter Integrity Is Associated With Gait Impairment And Falls In Mild Cognitive Impairment. Results From The Gait And Brain Study, Jonatan A. Snir, Robert Bartha, Manuel Montero-Odasso

Medical Biophysics Publications

© 2019 The Authors Background: Mild Cognitive Impairment (MCI) is an intermediate state between normal cognition and dementia that is associated with twice the risk of falls. It is unknown whether white matter integrity (WMI) is associated with increased risk of falls in MCI. The purpose of this study was to evaluate if early changes in WMI were associated with gait impairment and falls. Methods: Forty-three participants with MCI from the Gait and Brain Study underwent standardized assessment of cognition, gait performance under single and dual-task conditions (walking while talking), and WMI using 3 Tesla diffusion tensor imaging (DTI). Macro-structural …

Detection Of Active Caspase-3 In Mouse Models Of Stroke And Alzheimer's Disease With A Novel Dual Positron Emission Tomography/Fluorescent Tracer [ 68 Ga]Ga-Tc3-Ogdota, Valeriy G. Ostapchenko, Jonatan Snir, Mojmir Suchy, Jue Fan, M. Rebecca Cobb, Blaine A. Chronik, Michael Kovacs, Vania F. Prado, Robert H.E. Hudson, Stephen H. Pasternak, Marco A.M. Prado, Robert Bartha

Medical Biophysics Publications

© 2019 Valeriy G. Ostapchenko et al. Apoptosis is a feature of stroke and Alzheimer's disease (AD), yet there is no accepted method to detect or follow apoptosis in the brain in vivo. We developed a bifunctional tracer [ 68 Ga]Ga-TC3-OGDOTA containing a cell-penetrating peptide separated from fluorescent Oregon Green and 68 Ga-bound labels by the caspase-3 recognition peptide DEVD. We hypothesized that this design would allow [ 68 Ga]Ga-TC3-OGDOTA to accumulate in apoptotic cells. In vitro, Ga-TC3-OGDOTA labeled apoptotic neurons following exposure to camptothecin, oxygen-glucose deprivation, and β-amyloid oligomers. In vivo, PET showed accumulation of [ 68 Ga]Ga-TC3-OGDOTA in …

The Canadian Dementia Imaging Protocol: Harmonization Validity For Morphometry Measurements, Olivier Potvin, Isabelle Chouinard, Louis Dieumegarde, Robert Bartha, Pierre Bellec, D. Louis Collins, Maxime Descoteaux, Rick Hoge, Joel Ramirez, Christopher J.M. Scott, Eric E. Smith, Stephen C. Strother, Sandra E. Black, Simon Duchesne

Medical Biophysics Publications

© 2019 The Authors The harmonized Canadian Dementia Imaging Protocol (CDIP) has been developed to suit the needs of a number of co-occurring Canadian studies collecting data on brain changes across adulthood and neurodegeneration. In this study, we verify the impact of CDIP parameters compliance on total brain volume variance using 86 scans of the same individual acquired on various scanners. Data included planned data collection acquired within the Consortium pour l'identification précoce de la maladie Alzheimer - Québec (CIMA-Q) and Canadian Consortium on Neurodegeneration in Aging (CCNA) studies, as well as opportunistic data collection from various protocols. For images …

The Importance Of Costing Perspective: An Example Evaluating The Cost-Effectiveness Of A Locking Versus Nonlocking Plate In Medial Opening Wedge High Tibial Osteotomy, Codie A. Primeau, Jacquelyn D. Marsh, Trevor B. Birmingham

Bone and Joint Institute

No abstract provided.

Repeatability Of Measuring Knee Flexion Angles With Wearable Inertial Sensors, M. C. Fennema, R. A. Bloomfield, B. A. Lanting

Bone and Joint Institute

No abstract provided.

Measuring And Reporting Of Vertebral Endplate Bone Marrow Lesions As Seen On Mri (Modic Changes): Recommendations From The Issls Degenerative Spinal Phenotypes Group, For The Issls Degenerative Spinal Phenotypes Group, Aaron J. Fields, Michele C. Battié, Richard J. Herzog

Bone and Joint Institute

No abstract provided.

The Association Between Occupational Loading And Spine Degeneration On Imaging – A Systematic Review And Meta-Analysis, Luciana G. Macedo, Michele C. Battié

Bone and Joint Institute

No abstract provided.

A Novel Technique For Measurement Of Orthodontic Mini-Implant Stability Using The Osstell Isq Device, Yara K. Hosein, S. Jeffrey Dixon, Amin S. Rizkalla, Ali Tassi

Bone and Joint Institute

© 2019 by The EH Angle Education and Research Foundation, Inc. Objectives: To develop and validate a method for application of the Osstell ISQ device in the assessment of mini-implant stability. Materials and Methods: An adaptor was developed for attachment of Osstell's SmartPeg onto a variety of orthodontic mini-implants. For validation of the adaptor, Benefit mini-implants were inserted into bone blocks that mimicked different stability conditions. The Osstell device was used to assess mini-implant stability with the adaptor (test measurement) and conventional SmartPeg attachment (gold-standard measurement). Implant stability quotient (ISQ) values were assessed for agreement, repeatability, and reproducibility. Results: Strong …

An Anthropometric Assessment Of The Proximal Hamate Autograft For Scaphoid Proximal Pole Reconstruction, Kitty Wu, Clare Padmore, Emily Lalone, Nina Suh

Bone and Joint Institute

© 2019 American Society for Surgery of the Hand Purpose: Fragmentation of the scaphoid proximal pole secondary to avascular necrosis presents a difficult reconstructive problem. This anthropometric study assesses the utility of the ipsilateral proximal hamate for complete osteochondral scaphoid proximal pole reconstruction. Methods: Twenty-nine cadaveric specimens underwent computed tomography scanning and 3-dimensional reconstruction of the carpus and distal radius. Scaphoid height was measured and a third of its height was used to simulate resection of the proximal scaphoid pole and extent of hamate autograft required. The proximal scaphoid and hamate were divided into 6 sections, and compared using an …

Bone Repair And Regenerative Biomaterials: Towards Recapitulating The Microenvironment, Neda Aslankoohi, Dibakar Mondal, Amin S. Rizkalla, Kibret Mequanint

Bone and Joint Institute

© 2019 by the authors. Biomaterials and tissue engineering scaffolds play a central role to repair bone defects. Although ceramic derivatives have been historically used to repair bone, hybrid materials have emerged as viable alternatives. The rationale for hybrid bone biomaterials is to recapitulate the native bone composition to which these materials are intended to replace. In addition to the mechanical and dimensional stability, bone repair scaffolds are needed to provide suitable microenvironments for cells. Therefore, scaffolds serve more than a mere structural template suggesting a need for better and interactive biomaterials. In this review article, we aim to provide …

Clinimetrics: Short Western Ontario Rotator Cuff Index, Rochelle Furtado, Joy C. Macdermid

Bone and Joint Institute

No abstract provided.

Effects Of Arthroscopic Vs. Mini-Open Rotator Cuff Repair On Function, Pain & Range Of Motion. A Systematic Review And Meta-Analysis, G Nazari, Jc Macdermid, D Bryant, N Dewan

Bone and Joint Institute

Objective To assess the effectiveness of arthroscopic versus mini-open rotator cuff repair on function, pain and range of motion at 3-, 6- and 12-month follow ups. Design Systematic review and meta-analysis of randomized controlled trials. Setting Clinical setting. Participants Patients 18 years and older with a rotator cuff tear. Intervention/Comparison Arthroscopic/mini-open rotator cuff repair surgery followed by post operative rehabilitation. Main outcome measures Function and pain. Results Six RCTs (n = 670) were included. The pooled results, demonstrated no significant difference between arthroscopic and mini open approach to rotator cuff repair on function (very low quality, 4 RCTs, 495 patients, …

The Stability Study: A Protocol For A Multicenter Randomized Clinical Trial Comparing Anterior Cruciate Ligament Reconstruction With And Without Lateral Extra-Articular Tenodesis In Individuals Who Are At High Risk Of Graft Failure, A Getgood, D Bryant, A Firth, R Litchfield

Bone and Joint Institute

BackgroundThe purpose of anterior cruciate ligament reconstruction (ACLR) is to restore stability to the knee. Persistent rotational laxity following ACLR has been correlated with poor outcome and graft failure. We hypothesize that anterolateral complex reconstruction by way of a Modified Lemaire Lateral Extra-articular Tenodesis (LET) in combination with single bundle ACLR would reduce the risk of persistent rotatory laxity in young individuals who are deemed as being at high risk of failure. We will conduct a pragmatic, multicenter, randomized clinical trial comparing standard single bundle hamstring ACLR with combined ACLR and LET.MethodsSix-hundred patients (300 per group) aged 25years or less …

The Effectiveness Of Surgical Vs Conservative Interventions On Pain And Function In Patients With Shoulder Impingement Syndrome. A Systematic Review And Meta-Analysis, G Nazari, Jc Macdermid, D Bryant, Gs Athwal

Bone and Joint Institute

Objective To assess the effectiveness of surgical vs conservative interventions on pain and function in patients with subacromial impingement syndrome. Design Systematic review and meta-analysis of randomized controlled trials. Setting Clinical setting. Participants Patients 18 years and older with subacromial impingement syndrome. Intervention/Comparison Surgical intervention plus postoperative physiotherapy / placebo surgery plus physiotherapy or physiotherapy only. Main outcome measures Pain and function. Results 11 RCTs (n = 919) were included. The pooled results displayed no statistically or clinically different between surgery plus physiotherapy vs physiotherapy alone on pain levels at 3-, 6-months, 5- and 10 years follow up (moderate quality, …