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A Short Remark On Multipurpose Laser Therapy “Helios” In Ukraine And Its Potential Application For Treatment Of Neurology Disorders, Florentin Smarandache, Volodymyr Krasnoholovets, Victor Christianto, Rizha Vitania, The Houw Liong 2020 University of New Mexico

A Short Remark On Multipurpose Laser Therapy “Helios” In Ukraine And Its Potential Application For Treatment Of Neurology Disorders, Florentin Smarandache, Volodymyr Krasnoholovets, Victor Christianto, Rizha Vitania, The Houw Liong

Branch Mathematics and Statistics Faculty and Staff Publications

However, a truly multipurpose laser therapy method is very rarely available. Here we introduce a multipurpose laser therapy device in Ukraine, which is capable to take care a multitude of diseases. It is called “Helios”, by one of us (VK). We also give a case where a patient who suffered from Covid-19 has been treated successfully until he is recovered to healthy condition. In the last section we also discuss potential future application of Helios for other fields; i.e. neurology disorders.


Clincial Translational Science Research Of The Functional Role Of Large Conductance Potassium Channels In Selective Destruction Of Triple Negative Breast Cancer Cells, Gina Sizemore 2020 West Virginia University

Clincial Translational Science Research Of The Functional Role Of Large Conductance Potassium Channels In Selective Destruction Of Triple Negative Breast Cancer Cells, Gina Sizemore

Graduate Theses, Dissertations, and Problem Reports (ETD)

ABSTRACT

The preliminary background that puts this research into context is threefold; it is the aggressive nature of triple negative breast cancer (TNBC), the complexity surrounding its pathology, and the significant lack of targeted treatment for this disease. To clarify the focus of my research, I have concentrated on identifying a targeted treatment for TNBC. In the process, I have identified cycles of reciprocity between treatment, clinical diagnosis, staging, and pathology that will be addressed in smaller papers. However, the weight of this work is in the discovery of a novel target for triple negative breast cancer. The value of …


Comparison Of Quality Control Methods For Automated Diffusion Tensor Imaging Analysis Pipelines, Seyyed M.H. Haddad, Christopher J.M. Scott, Miracle Ozzoude, Melissa F. Holmes, Stephen R. Arnott, Nuwan D. Nanayakkara, Joel Ramirez, Sandra E. Black, Dar Dowlatshahi, Stephen C. Strother, Richard H. Swartz, Sean Symons, Manuel Montero-Odasso, Robert Bartha 2019 Robarts Research Institute

Comparison Of Quality Control Methods For Automated Diffusion Tensor Imaging Analysis Pipelines, Seyyed M.H. Haddad, Christopher J.M. Scott, Miracle Ozzoude, Melissa F. Holmes, Stephen R. Arnott, Nuwan D. Nanayakkara, Joel Ramirez, Sandra E. Black, Dar Dowlatshahi, Stephen C. Strother, Richard H. Swartz, Sean Symons, Manuel Montero-Odasso, Robert Bartha

Medical Biophysics Publications

© 2019 Haddad et al. The processing of brain diffusion tensor imaging (DTI) data for large cohort studies requires fully automatic pipelines to perform quality control (QC) and artifact/outlier removal procedures on the raw DTI data prior to calculation of diffusion parameters. In this study, three automatic DTI processing pipelines, each complying with the general ENIGMA framework, were designed by uniquely combining multiple image processing software tools. Different QC procedures based on the RESTORE algorithm, the DTIPrep protocol, and a combination of both methods were compared using simulated ground truth and artifact containing DTI datasets modeling eddy current induced distortions, …


Mousebytes, An Open-Access High-Throughput Pipeline And Database For Rodent Touchscreen-Based Cognitive Assessment, Flavio H. Beraldo, Daniel Palmer, Sara Memar, David I. Wasserman, Wai Jane V. Lee, Shuai Liang, Samantha D. Creighton, Benjamin Kolisnyk, Matthew F. Cowan, Justin Mels, Talal S. Masood, Chris Fodor, Mohammed A. Al-Onaizi, Robert Bartha, Tom Gee, Lisa M. Saksida, Timothy J. Bussey, Stephen S. Strother, Vania F. Prado, Boyer D. Winters, Marco A.M. Prado 2019 Robarts Research Institute

Mousebytes, An Open-Access High-Throughput Pipeline And Database For Rodent Touchscreen-Based Cognitive Assessment, Flavio H. Beraldo, Daniel Palmer, Sara Memar, David I. Wasserman, Wai Jane V. Lee, Shuai Liang, Samantha D. Creighton, Benjamin Kolisnyk, Matthew F. Cowan, Justin Mels, Talal S. Masood, Chris Fodor, Mohammed A. Al-Onaizi, Robert Bartha, Tom Gee, Lisa M. Saksida, Timothy J. Bussey, Stephen S. Strother, Vania F. Prado, Boyer D. Winters, Marco A.M. Prado

Medical Biophysics Publications

© 2019, eLife Sciences Publications Ltd. All rights reserved. Open Science has changed research by making data accessible and shareable, contributing to replicability to accelerate and disseminate knowledge. However, for rodent cognitive studies the availability of tools to share and disseminate data is scarce. Automated touchscreen-based tests enable systematic cognitive assessment with easily standardised outputs that can facilitate data dissemination. Here we present an integration of touchscreen cognitive testing with an open-access database public repository (mousebytes.ca), as well as a Web platform for knowledge dissemination (https://touchscreencognition.org). We complement these resources with the largest dataset of age-dependent high-level cognitive assessment of …


Genome-Wide Association Analysis Of Hippocampal Volume Identifies Enrichment Of Neurogenesis-Related Pathways, Emrin Horgusluoglu-Moloch, Shannon L. Risacher, Paul K. Crane, Derrek Hibar, Paul M. Thompson, Andrew J. Saykin, Kwangsik Nho, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, John Morris, Leslie M. Shaw, Jeffrey Kaye, Joseph Quinn, Lisa Silbert, Betty Lind, Raina Carter, Sara Dolen, Lon S. Schneider, Sonia Pawluczyk, Mauricio Beccera, Liberty Teodoro, Bryan M. Spann, James Brewer, Helen Vanderswag, Adam Fleisher 2019 Indiana University School of Medicine

Genome-Wide Association Analysis Of Hippocampal Volume Identifies Enrichment Of Neurogenesis-Related Pathways, Emrin Horgusluoglu-Moloch, Shannon L. Risacher, Paul K. Crane, Derrek Hibar, Paul M. Thompson, Andrew J. Saykin, Kwangsik Nho, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, John Morris, Leslie M. Shaw, Jeffrey Kaye, Joseph Quinn, Lisa Silbert, Betty Lind, Raina Carter, Sara Dolen, Lon S. Schneider, Sonia Pawluczyk, Mauricio Beccera, Liberty Teodoro, Bryan M. Spann, James Brewer, Helen Vanderswag, Adam Fleisher

Medical Biophysics Publications

© 2019, The Author(s). Adult neurogenesis occurs in the dentate gyrus of the hippocampus during adulthood and contributes to sustaining the hippocampal formation. To investigate whether neurogenesis-related pathways are associated with hippocampal volume, we performed gene-set enrichment analysis using summary statistics from a large-scale genome-wide association study (N = 13,163) of hippocampal volume from the Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Consortium and two year hippocampal volume changes from baseline in cognitively normal individuals from Alzheimer’s Disease Neuroimaging Initiative Cohort (ADNI). Gene-set enrichment analysis of hippocampal volume identified 44 significantly enriched biological pathways (FDR corrected p-value < 0.05), of which 38 pathways were related to neurogenesis-related processes including neurogenesis, generation of new neurons, neuronal development, and neuronal migration and differentiation. For genes highly represented in the significantly enriched neurogenesis-related pathways, gene-based association analysis identified TESC, ACVR1, MSRB3, and DPP4 as significantly associated with hippocampal volume. Furthermore, co-expression network-based functional analysis of gene expression data in the hippocampal subfields, CA1 and CA3, from 32 normal controls showed that distinct co-expression modules were mostly enriched in neurogenesis related pathways. Our results suggest that neurogenesis-related pathways may be enriched for hippocampal volume and that hippocampal volume may serve as a potential phenotype for the investigation of human adult neurogenesis.


The Bin1 Rs744373 Snp Is Associated With Increased Tau-Pet Levels And Impaired Memory, Nicolai Franzmeier, Anna Rubinski, Julia Neitzel, Michael Ewers, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowski, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Lew Kuller, Marcus Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, David Holtzman, Marek M. Mesulam, William Potter, Peter Snyder, Adam Schwartz, Tom Montine, Ronald G. Thomas, Michael Donohue 2019 Klinikum der Universität München

The Bin1 Rs744373 Snp Is Associated With Increased Tau-Pet Levels And Impaired Memory, Nicolai Franzmeier, Anna Rubinski, Julia Neitzel, Michael Ewers, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowski, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Lew Kuller, Marcus Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, David Holtzman, Marek M. Mesulam, William Potter, Peter Snyder, Adam Schwartz, Tom Montine, Ronald G. Thomas, Michael Donohue

Medical Biophysics Publications

© 2019, The Author(s). The single nucleotide polymorphism (SNP) rs744373 in the bridging integrator-1 gene (BIN1) is a risk factor for Alzheimer’s disease (AD). In the brain, BIN1 is involved in endocytosis and sustaining cytoskeleton integrity. Post-mortem and in vitro studies suggest that BIN1-associated AD risk is mediated by increased tau pathology but whether rs744373 is associated with increased tau pathology in vivo is unknown. Here we find in 89 older individuals without dementia, that BIN1 rs744373 risk-allele carriers show higher AV1451 tau-PET across brain regions corresponding to Braak stages II–VI. In contrast, the BIN1 rs744373 SNP was not associated …


Multimodal Hippocampal Subfield Grading For Alzheimer’S Disease Classification, Kilian Hett, Vinh Thong Ta, Gwenaëlle Catheline, Thomas Tourdias, José V. Manjón, Pierrick Coupé, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Maria Carrillo, Lew Kuller, Marc Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, Davie Holtzman, M. Marcel Mesulam, William Potter, Peter Snyder, Tom Montine 2019 Université de Bordeaux

Multimodal Hippocampal Subfield Grading For Alzheimer’S Disease Classification, Kilian Hett, Vinh Thong Ta, Gwenaëlle Catheline, Thomas Tourdias, José V. Manjón, Pierrick Coupé, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Maria Carrillo, Lew Kuller, Marc Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, Davie Holtzman, M. Marcel Mesulam, William Potter, Peter Snyder, Tom Montine

Medical Biophysics Publications

© 2019, The Author(s). Numerous studies have proposed biomarkers based on magnetic resonance imaging (MRI) to detect and predict the risk of evolution toward Alzheimer’s disease (AD). Most of these methods have focused on the hippocampus, which is known to be one of the earliest structures impacted by the disease. To date, patch-based grading approaches provide among the best biomarkers based on the hippocampus. However, this structure is complex and is divided into different subfields, not equally impacted by AD. Former in-vivo imaging studies mainly investigated structural alterations of these subfields using volumetric measurements and microstructural modifications with mean diffusivity …


3d Vessel-Wall Virtual Histology Of Whole-Body Perfused Mice Using A Novel Heavy Element Stain, P. Joy Dunmore-Buyze, Charmainne Cruje, Zengxuan Nong, Jason J. Lee, John A. Kiernan, J. Geoffrey Pickering, Maria Drangova 2019 Robarts Research Institute

3d Vessel-Wall Virtual Histology Of Whole-Body Perfused Mice Using A Novel Heavy Element Stain, P. Joy Dunmore-Buyze, Charmainne Cruje, Zengxuan Nong, Jason J. Lee, John A. Kiernan, J. Geoffrey Pickering, Maria Drangova

Medical Biophysics Publications

Virtual histology – utilizing high-resolution three-dimensional imaging – is becoming readily available. Micro-computed tomography (micro-CT) is widely available and is often coupled with x-ray attenuating histological stains that mark specific tissue components for 3D virtual histology. In this study we describe a new tri-element x-ray attenuating stain and perfusion protocol that provides micro-CT contrast of the entire vasculature of an intact mouse. The stain – derived from an established histology stain (Verhoeff’s) – is modified to enable perfusion through the vasculature; the attenuating elements of the stain are iodine, aluminum, and iron. After a 30-minute perfusion through the vasculature (10-minute …


Quantitative Study Of The Antimicrobial Effects Of Silver On The Motility Of Escherichia Coli, Benjamin Russell 2019 University of Arkansas, Fayetteville

Quantitative Study Of The Antimicrobial Effects Of Silver On The Motility Of Escherichia Coli, Benjamin Russell

Graduate Theses and Dissertations

In recent decades, the number of antibiotic-resistant bacterial infections has grown to become a serious global threat. This rise can be attributed to the widespread misuse of antibiotics and the lack of newly developed drugs to fight resistant organisms. Novel bactericidal substances have, therefore, garnered significant research interest. Silver, due to its powerful antimicrobial effects, is one such substance. Silver is typically most effective in cationic form; however, advancements in nanotechnology have paved the way for the controlled fabrication of nano-silver. Silver nanoparticles have been shown to have increased antibacterial potency for a variety of reasons, including the release of …


Accelerated 129xe Mri Morphometry Of Terminal Airspace Enlargement: Feasibility In Volunteers And Those With Alpha-1 Antitrypsin Deficiency, Alexei Ouriadov, Fumin Guo, David G McCormack, Grace Parraga 2019 Western University

Accelerated 129xe Mri Morphometry Of Terminal Airspace Enlargement: Feasibility In Volunteers And Those With Alpha-1 Antitrypsin Deficiency, Alexei Ouriadov, Fumin Guo, David G Mccormack, Grace Parraga

Medical Biophysics Publications

PURPOSE: Multi-b diffusion-weighted hyperpolarized inhaled-gas MRI provides imaging biomarkers of terminal airspace enlargement including ADC and mean linear intercept (L

METHODS: We evaluated multi-b (0, 12, 20, 30, and 45.5 s/cm

RESULTS: For the HV subgroup, mean differences of 5%, 2%, and 8% were observed between fully sampled and undersampled k-space for ADC, L

CONCLUSIONS: Accelerated multi-b diffusion-weighted


Synergistic Toxicity In An In Vivo Model Of Neurodegeneration Through The Co-Expression Of Human Tdp-43M337v And TauT175d Protein, Alexander J. Moszczynski, Madeline Harvey, Niveen Fulcher, Cleusa de Oliveira, Patrick McCunn, Neil Donison, Robert Bartha, Susanne Schmid, Michael J. Strong, Kathryn Volkening 2019 Robarts Research Institute

Synergistic Toxicity In An In Vivo Model Of Neurodegeneration Through The Co-Expression Of Human Tdp-43M337v And TauT175d Protein, Alexander J. Moszczynski, Madeline Harvey, Niveen Fulcher, Cleusa De Oliveira, Patrick Mccunn, Neil Donison, Robert Bartha, Susanne Schmid, Michael J. Strong, Kathryn Volkening

Medical Biophysics Publications

Although it has been suggested that the co-expression of multiple pathological proteins associated with neurodegeneration may act synergistically to induce more widespread neuropathology, experimental evidence of this is sparse. We have previously shown that the expression of Thr175Asp-tau (tauT175D) using somatic gene transfer with a stereotaxically-injected recombinant adeno-associated virus (rAAV9) vector induces tau pathology in rat hippocampus. In this study, we have examined whether the co-expression of human tauT175D with mutant human TDP-43 (TDP-43M337V) will act synergistically. Transgenic female Sprague-Dawley rats that inducibly express mutant human TDP-43M337V using the choline acetyltransferase (ChAT) tetracycline response element (TRE) driver with activity modulating …


Normalisation Of Mri Ventilation Heterogeneity In Severe Asthma By Dupilumab, Sarah Svenningsen, Ehsan Ahmed Haider, Rachel L Eddy, Grace Parraga, Parameswaran Nair 2019 Western University

Normalisation Of Mri Ventilation Heterogeneity In Severe Asthma By Dupilumab, Sarah Svenningsen, Ehsan Ahmed Haider, Rachel L Eddy, Grace Parraga, Parameswaran Nair

Medical Biophysics Publications

Ventilation heterogeneity in asthma could be due to many reasons. Luminal obstruction due to inflammatory cells or mucus, smooth muscle constriction and airway wall thickness could all contribute individually or collectively to ventilation heterogeneity. Interleukin-4 and interleukin-13, acting through the common interleukin-4 receptor, have the potential to modulate all of these features of asthma.1 Inhaled hyperpolarised gas MRI provides a way to regionally visualise and quantify the functional consequence of these features.2 Dupilumab is a fully human monoclonal antibody directed against the alpha-subunit of the interleukin-4 receptor.3 Here, we report a severe asthmatic who showed significant improvement and normalisation of …


Ventricular Volume Expansion In Presymptomatic Genetic Frontotemporal Dementia, Tamara P. Tavares, Derek G.V. Mitchell, Kristy Coleman, Christen Shoesmith, Robert Bartha, David M. Cash, Katrina M. Moore, John Van Swieten, Barbara Borroni, Daniela Galimberti, Maria Carmela Tartaglia, James Rowe, Caroline Graff, Fabrizio Tagliavini, Giovanni Frisoni, Stefano Cappa, Robert Laforce, Alexandre De Mendonça, Sandro Sorbi, Garrick Wallstrom, Mario Masellis, Jonathan D. Rohrer, Elizabeth C. Finger 2019 Graduate Program in Neuroscience and Brain and Mind Institute

Ventricular Volume Expansion In Presymptomatic Genetic Frontotemporal Dementia, Tamara P. Tavares, Derek G.V. Mitchell, Kristy Coleman, Christen Shoesmith, Robert Bartha, David M. Cash, Katrina M. Moore, John Van Swieten, Barbara Borroni, Daniela Galimberti, Maria Carmela Tartaglia, James Rowe, Caroline Graff, Fabrizio Tagliavini, Giovanni Frisoni, Stefano Cappa, Robert Laforce, Alexandre De Mendonça, Sandro Sorbi, Garrick Wallstrom, Mario Masellis, Jonathan D. Rohrer, Elizabeth C. Finger

Medical Biophysics Publications

Copyright © 2019 American Academy of Neurology. ObjectiveTo characterize the time course of ventricular volume expansion in genetic frontotemporal dementia (FTD) and identify the onset time and rates of ventricular expansion in presymptomatic FTD mutation carriers.MethodsParticipants included patients with a mutation in MAPT, PGRN, or C9orf72, or first-degree relatives of mutation carriers from the GENFI study with MRI scans at study baseline and at 1 year follow-up. Ventricular volumes were obtained from MRI scans using FreeSurfer, with manual editing of segmentation and comparison to fully automated segmentation to establish reliability. Linear mixed models were used to identify differences in ventricular …


Chronic Obstructive Pulmonary Disease: Thoracic Ct Texture Analysis And Machine Learning To Predict Pulmonary Ventilation, Andrew Westcott, Dante P I Capaldi, David G McCormack, Aaron D Ward, Aaron Fenster, Grace Parraga 2019 Western University

Chronic Obstructive Pulmonary Disease: Thoracic Ct Texture Analysis And Machine Learning To Predict Pulmonary Ventilation, Andrew Westcott, Dante P I Capaldi, David G Mccormack, Aaron D Ward, Aaron Fenster, Grace Parraga

Medical Biophysics Publications

Background Fixed airflow limitation and ventilation heterogeneity are common in chronic obstructive pulmonary disease (COPD). Conventional noncontrast CT provides airway and parenchymal measurements but cannot be used to directly determine lung function. Purpose To develop, train, and test a CT texture analysis and machine-learning algorithm to predict lung ventilation heterogeneity in participants with COPD. Materials and Methods In this prospective study (


Visualization Of The Small Airways:What It Is And Why It Matters, Mark L Schiebler, Grace Parraga 2019 Western University

Visualization Of The Small Airways:What It Is And Why It Matters, Mark L Schiebler, Grace Parraga

Medical Biophysics Publications

When the earth transitioned to an oxygen-containing atmosphere, many bacterial species were killed by the free radicals that developed in their cytoplasm. New life forms took advantage of this change by evolving to use oxygen as the final resting place for electrons involved in the Krebs cycle. Animals today rely on getting oxygen into the blood stream and getting carbon dioxide out by ventilation through sequentially smaller and smaller tubes until diffusion takes over, finally reaching the terminal respiratory bronchiole and its associated alveoli for gas exchange. All animals are obligate aerobes. One group has estimated that there are 274 …


Cardiovascular Risk Scoring And Magnetic Resonance Imaging Detected Subclinical Cerebrovascular Disease, Sonia S Anand, Jack V Tu, Dipika Desai, Phillip Awadalla, Paula Robson, Sébastien Jacquemont, Trevor Dummer, Nhu Le, Louise Parker, Paul Poirier, Koon Teo, Scott A Lear, Salim Yusuf, Jean-Claude Tardif, Francois Marcotte, David Busseuil, Jean-Pierre Després, Sandra E Black, Anish Kirpalani, Grace Parraga, Michael D Noseworthy, Alexander Dick, Jonathan Leipsic, David Kelton, Jennifer Vena, Melissa Thomas, Karleen M Schulze, Eric Larose, Alan R Moody, Eric E Smith, Matthias G Friedrich 2019 Western University

Cardiovascular Risk Scoring And Magnetic Resonance Imaging Detected Subclinical Cerebrovascular Disease, Sonia S Anand, Jack V Tu, Dipika Desai, Phillip Awadalla, Paula Robson, Sébastien Jacquemont, Trevor Dummer, Nhu Le, Louise Parker, Paul Poirier, Koon Teo, Scott A Lear, Salim Yusuf, Jean-Claude Tardif, Francois Marcotte, David Busseuil, Jean-Pierre Després, Sandra E Black, Anish Kirpalani, Grace Parraga, Michael D Noseworthy, Alexander Dick, Jonathan Leipsic, David Kelton, Jennifer Vena, Melissa Thomas, Karleen M Schulze, Eric Larose, Alan R Moody, Eric E Smith, Matthias G Friedrich

Medical Biophysics Publications

AIMS: Cardiovascular risk factors are used for risk stratification in primary prevention. We sought to determine if simple cardiac risk scores are associated with magnetic resonance imaging (MRI)-detected subclinical cerebrovascular disease including carotid wall volume (CWV), carotid intraplaque haemorrhage (IPH), and silent brain infarction (SBI).

METHODS AND RESULTS: A total of 7594 adults with no history of cardiovascular disease (CVD) underwent risk factor assessment and a non-contrast enhanced MRI of the carotid arteries and brain using a standardized protocol in a population-based cohort recruited between 2014 and 2018. The non-lab-based INTERHEART risk score (IHRS) was calculated in all participants; the …


Eliminating The Effects Of Motion During Radiofrequency Lesion Delivery Using A Novel Contact-Force Controller., Daniel Gelman, Allan C Skanes, Douglas L Jones, Michael Timofeyev, Tal Bar-On, Maria Drangova 2019 Western University

Eliminating The Effects Of Motion During Radiofrequency Lesion Delivery Using A Novel Contact-Force Controller., Daniel Gelman, Allan C Skanes, Douglas L Jones, Michael Timofeyev, Tal Bar-On, Maria Drangova

Medical Biophysics Publications

INTRODUCTION: Catheter-tissue contact force is a determinant of radiofrequency (RF) ablation lesion effectiveness. However, ablation on a beating heart is subject to force variability, making it difficult to optimally deliver consistently durable and transmural lesions. This work evaluates improvements in contact force stability and lesion reproducibility by using a catheter contact-force controller (CFC) during lesion delivery in vitro and in vivo.

METHODS AND RESULTS: Using a sheath and force-sensing catheter, an experienced operator attempted to maintain a constant force of 20 g at targets within the atria and left ventricle of a pig manually and using the CFC; the average …


Development Of A Stand-Alone Dcs System For Monitoring Absolute Cerebral Blood Flow, Mahro Khalid, Daniel Milej, Ajay Rajaram, Androu Abdalmalak, Laura Morrison, Mamadou Diop, Keith S.T. Lawrence 2019 Lawson Health Research Institute

Development Of A Stand-Alone Dcs System For Monitoring Absolute Cerebral Blood Flow, Mahro Khalid, Daniel Milej, Ajay Rajaram, Androu Abdalmalak, Laura Morrison, Mamadou Diop, Keith S.T. Lawrence

Medical Biophysics Publications

© 2019 Optical Society of America. Diffuse correlation spectroscopy (DCS) is a noninvasive optical technique for monitoring cerebral blood flow (CBF). This work presents a stand-alone DCS system capable of monitoring absolute CBF by incorporating a quantitative dynamic contrast-enhanced (DCE) technique. Multi-distance data were acquired to measure the tissue optical properties and to perform DCE experiments. Feasibility of the technique was assessed in piglets in which the optical properties were measured independently by time-resolved near-infrared spectroscopy. A strong linear correlation was observed between CBF values derived using the two sets of optical properties, demonstrating that this hybrid DCS approach can …


Evaluation Of Hyperspectral Nirs For Quantitative Measurements Of Tissue Oxygen Saturation By Comparison To Time-Resolved Nirs, Matthew Kewin, Ajay Rajaram, Daniel Milej, Androu Abdalmalak, Laura Morrison, Mamadou Diop, Keith St Lawrence 2019 Lawson Health Research Institute

Evaluation Of Hyperspectral Nirs For Quantitative Measurements Of Tissue Oxygen Saturation By Comparison To Time-Resolved Nirs, Matthew Kewin, Ajay Rajaram, Daniel Milej, Androu Abdalmalak, Laura Morrison, Mamadou Diop, Keith St Lawrence

Medical Biophysics Publications

© 2019 Optical Society of America. Near-infrared spectroscopy (NIRS) is considered ideal for brain monitoring during preterm infancy because it is non-invasive and provides a continuous measure of tissue oxygen saturation (StO2). Hyperspectral NIRS (HS NIRS) is an inexpensive, quantitative modality that can measure tissue optical properties and oxygen saturation (StO2) by differential spectroscopy. In this study, experiments were conducted using newborn piglets to measure StO2 across a range of oxygenation levels from hyperoxia to hypoxia by HS and time-resolved (TR) NIRS for validation. A strong correlation between StO2 measurements from the two techniques was observed (R2 = 0.98, average …


Hyperpolarized Helium 3 Mri In Mild-To-Moderate Asthma: Prediction Of Postbronchodilator Reversibility, Rachel L Eddy, Sarah Svenningsen, Christopher Licskai, David G McCormack, Grace Parraga 2019 Western University

Hyperpolarized Helium 3 Mri In Mild-To-Moderate Asthma: Prediction Of Postbronchodilator Reversibility, Rachel L Eddy, Sarah Svenningsen, Christopher Licskai, David G Mccormack, Grace Parraga

Medical Biophysics Publications

Background: Longitudinal progression to irreversible airflow limitation occurs in approximately 10% of patients with asthma, but it is difficult to identify patients who are at risk for this transition.

Purpose: To investigate 6-year longitudinal changes in hyperpolarized helium 3 (3He) MRI ventilation defects in study participants with mild-to-moderate asthma and identify predictors of longitudinal changes in postbronchodilator forced expiratory volume in 1 second (FEV1) reversibility

Materials and Methods: Spirometry and hyperpolarized 3He MRI were evaluated in participants with mild-to-moderate asthma in two prospectively planned visits approximately 6 years apart. Participants underwent methacholine challenge at baseline (January 2010 to April 2011) …


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