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https://www.readbyqxmd.com/read/28398210/out-of-field-doses-from-pediatric-craniospinal-irradiations-using-3d-crt-imrt-helical-tomotherapy-and-electron-based-therapy
#1
Marijke De Saint-Hubert, Dirk Verellen, Kenneth Poels, Wouter Crijns, Federica Magliona, Tom Depuydt, Filip Vanhavere, Lara Struelens
Medulloblastoma treatment involves irradiation of the entire central nervous system, i.e craniospinal irradiation (CSI). This is associated with significant exposure of large volumes of healthy tissue with a growing concern regarding treatment associated side effects. The current study compares out-of-field organ doses in children receiving CSI with three-dimensional-conformal radiotherapy (3D-CRT), intensity modulated radiotherapy (IMRT), helical tomotherapy (HT) and an electron-based technique, including as well radiation doses resulting from imaging performed during treatment...
April 11, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28375841/a-mock-heart-engineered-with-helical-aramid-fibers-for-in-vitro-cardiovascular-device-testing
#2
So-Hyun Jansen-Park, Po-Lin Hsu, Indra Müller, Ulrich Steinseifer, Dirk Abel, Rüdiger Autschbach, Rolf Rossaint, Thomas Schmitz-Rode
Mock heart circulation loops (MHCLs) serve as in-vitro platforms to investigate the physiological interaction between circulatory systems and cardiovascular devices. A mock heart (MH) engineered with silicone walls and helical aramid fibers, to mimic the complex contraction of a natural heart, has been developed to advance the MHCL previously developed in our group. A mock aorta with an anatomical shape enables the evaluation of a cannulation method for ventricular assist devices (VADs) and investigation of the usage of clinical measurement systems like pressure-volume catheters...
April 1, 2017: Biomedizinische Technik. Biomedical Engineering
https://www.readbyqxmd.com/read/28297441/comprehensive-dosimetric-planning-comparison-for-early-stage-non-small-cell-lung-cancer-with-sabr-fixed-beam-imrt-versus-vmat-versus-tomotherapy
#3
Ilma Xhaferllari, Omar El-Sherif, Stewart Gaede
Volumetric-modulated arc therapy (VMAT) is emerging as a leading technology in treating early-stage, non-small cell lung cancer (NSCLC) with stereotactic ablative radiotherapy (SABR). However, two other modalities capable of delivering intensity-modulated radiation therapy (IMRT) include fixed-beam and helical TomoTherapy (HT). This study aims to provide an extensive dosimetric comparison among these various IMRT techniques for treating early-stage NSCLC with SABR. Ten early-stage NSCLC patients were retrospectively optimized using three fixed-beam techniques via nine to eleven beams (high and low modulation step-and-shoot (SS), and sliding window (SW)), two VMAT techniques via two partial arcs (SmartArc (SA) and RapidArc (RA)), and three HT techniques via three different fan beam widths (1 cm, 2...
September 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28295788/creating-hemodynamic-atlases-of-cardiac-4d-flow-mri
#4
Merih Cibis, Mariana Bustamante, Jonatan Eriksson, Carl-Johan Carlhäll, Tino Ebbers
PURPOSE: Hemodynamic atlases can add to the pathophysiological understanding of cardiac diseases. This study proposes a method to create hemodynamic atlases using 4D Flow magnetic resonance imaging (MRI). The method is demonstrated for kinetic energy (KE) and helicity density (Hd ). MATERIALS AND METHODS: Thirteen healthy subjects underwent 4D Flow MRI at 3T. Phase-contrast magnetic resonance cardioangiographies (PC-MRCAs) and an average heart were created and segmented...
March 13, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28282389/4d-flow-mri-assessment-of-right-atrial-flow-patterns-in-the-normal-heart-influence-of-caval-vein-arrangement-and-implications-for-the-patent-foramen-ovale
#5
Jehill D Parikh, Jayant Kakarla, Bernard Keavney, John J O'Sullivan, Gary A Ford, Andrew M Blamire, Kieren G Hollingsworth, Louise Coats
AIM: To investigate atrial flow patterns in the normal adult heart, to explore whether caval vein arrangement and patency of the foramen ovale (PFO) may be associated with flow pattern. MATERIALS AND METHODS: Time-resolved, three-dimensional velocity encoded magnetic resonance imaging (4D flow) was employed to assess atrial flow patterns in thirteen healthy subjects (6 male, 40 years, range 25-50) and thirteen subjects (6 male, 40 years, range 21-50) with cryptogenic stroke and patent foramen ovale (CS-PFO)...
2017: PloS One
https://www.readbyqxmd.com/read/28268951/interventional-placement-of-thin-coil-shaped-implants-powered-wirelessly-for-monitoring-vital-signals-and-controlling-abnormal-activities-by-electro-stimulation
#6
Hidetoshi Ohta, Masanobu Honda, Makoto Takamiya
Various types of implants are being commonly used for monitoring vital signals and controlling the critically ill patient's condition such as arrhythmia, sick sinus syndrome, etc. For implanting these medical devices under the skin, surgery is inevitable. These days many patients are more willing to accept interventional therapies that are less invasive, especially inserting a catheter into a blood vessel or endoscopy through a natural orifice. To be able to use interventional therapy for implanting medical devices, they will need to be small enough to fit them through a catheter or the forceps channel of an endoscope...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28249288/responsiveness-of-coronary-arteries-to-nitroglycerin-under-hypoxia-the-importance-of-the-endothelium
#7
Masashi Tawa, Takashi Shimosato, Hiroshi Sakonjo, Tomio Okamura
BACKGROUND/AIMS: Nitroglycerin is widely used as a coronary vasodilator in the treatment of ischemic heart diseases. This study investigated the influence of hypoxia on nitroglycerin-induced relaxation in endothelium-intact and -denuded rabbit, monkey, and porcine coronary arteries. METHODS: Helically cut strips of coronary arteries were suspended in organ chambers, and isometric tension was recorded. RESULTS: Nitroglycerin concentration dependently relaxed endothelium-intact rabbit coronary arteries, which were not different under normoxic and hypoxic conditions...
2017: Pharmacology
https://www.readbyqxmd.com/read/28245984/conformational-and-thermal-characterization-of-left-ventricle-remodeling-post-myocardial-infarction
#8
V Samouillan, E Revuelta-López, C Soler-Botija, J Dandurand, Aleyda Benitez-Amaro, L Nasarre, D de Gonzalo-Calvo, A Bayes-Genis, C Lacabanne, V Llorente-Cortés
Adverse cardiac remodeling after myocardial infarction (MI) causes impaired ventricular function and heart failure. Histopathological characterization is commonly used to detect the location, size and shape of MI sites. However, the information about chemical composition, physical structure and molecular mobility of peri- and infarct zones post-MI is rather limited. The main objective of this work was to explore the spatiotemporal biochemical and biophysical alterations of key cardiac components post-MI. The FTIR spectra of healthy and remote myocardial tissue shows amides A, I, II and III associated with proteins in freeze-died tissue as major absorptions bands...
February 25, 2017: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/28227158/interventional-placement-of-thin-coil-shaped-implants-powered-wirelessly-for-monitoring-vital-signals-and-controlling-abnormal-activities-by-electro-stimulation
#9
Hidetoshi Ohta, Masanobu Honda, Makoto Takamiya, Hidetoshi Ohta, Masanobu Honda, Makoto Takamiya, Masanobu Honda, Hidetoshi Ohta, Makoto Takamiya
Various types of implants are being commonly used for monitoring vital signals and controlling the critically ill patient's condition such as arrhythmia, sick sinus syndrome, etc. For implanting these medical devices under the skin, surgery is inevitable. These days many patients are more willing to accept interventional therapies that are less invasive, especially inserting a catheter into a blood vessel or endoscopy through a natural orifice. To be able to use interventional therapy for implanting medical devices, they will need to be small enough to fit them through a catheter or the forceps channel of an endoscope...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28217410/design-and-analysis-of-a-field-modulated-magnetic-screw-for-artificial-heart
#10
Zhijian Ling, Jinghua Ji, Fangqun Wang, Fangfang Bian
This paper proposes a new electromechanical energy conversion system, called Field Modulated Magnetic Screw (FMMS) as a high force density linear actuator for artificial heart. This device is based on the concept of magnetic screw and linear magnetic gear. The proposed FMMS consists of three parts with the outer and inner carrying the radially magnetized helically permanent-magnet (PM), and the intermediate having a set of helically ferromagnetic pole pieces, which modulate the magnetic fields produced by the PMs...
May 2017: AIP Advances
https://www.readbyqxmd.com/read/28199087/expression-purification-and-properties-of-a-human-arachidonoyl-specific-isoform-of-diacylglycerol-kinase
#11
William Jennings, Sejal Doshi, Prasanta Kumar Hota, Aaron Prodeus, Stephanie Black, Richard M Epand
Diacylglycerol kinase ε (DGKε) catalyzes the phosphorylation of diacylglycerol, producing phosphatidic acid. DGKε demonstrates exquisite specificity for the acyl chains of diacylglycerol. This contributes to the enrichment of particular acyl chains within the lipids of the phosphatidylinositol cycle. Phosphatidylinositol is highly enriched with 1-stearoyl-2-arachidonoyl, which is important for maintaining cellular health. Dysregulation of DGKε perturbs lipid signaling and biosynthesis, which has been linked to epilepsy, Huntington's disease, and heart disease...
February 24, 2017: Biochemistry
https://www.readbyqxmd.com/read/28168514/limits-of-the-possible-diagnostic-image-quality-in-coronary-angiography-with-third-generation-dual-source-ct
#12
Marco M Ochs, Fabian Aus dem Siepen, Thomas Fritz, Florian Andre, Gitsios Gitsioudis, Grigorios Korosoglou, Sebastian Seitz, Yuriy Bogomazov, Christopher L Schlett, Roman Sokiranski, Andre Sommer, Friedemann Gückel, Matthias Brado, Hans-Ulrich Kauczor, Johannes Görich, Matthias G W Friedrich, Hugo A Katus, Sebastian J Buss
BACKGROUND: The usage of coronary CT angiography (CTA) is appropriate in patients with acute or chronic chest pain; however the diagnostic accuracy may be challenged with increased Agatston score (AS), increased heart rate, arrhythmia and severe obesity. Thus, we aim to determine the potential of the recently introduced third-generation dual-source CT (DSCT) for CTA in a 'real-life' clinical setting. METHODS: Two hundred and sixty-eight consecutive patients (age: 67 ± 10 years; BMI: 27 ± 5 kg/m²; 61% male) undergoing clinically indicated CTA with DSCT were included in the retrospective single-center analysis...
February 6, 2017: Clinical Research in Cardiology: Official Journal of the German Cardiac Society
https://www.readbyqxmd.com/read/28167762/phosphorylation-of-cardiac-myosin-binding-protein-c-releases-myosin-heads-from-the-surface-of-cardiac-thick-filaments
#13
Robert W Kensler, Roger Craig, Richard L Moss
Cardiac myosin binding protein C (cMyBP-C) has a key regulatory role in cardiac contraction, but the mechanism by which changes in phosphorylation of cMyBP-C accelerate cross-bridge kinetics remains unknown. In this study, we isolated thick filaments from the hearts of mice in which the three serine residues (Ser273, Ser282, and Ser302) that are phosphorylated by protein kinase A in the m-domain of cMyBP-C were replaced by either alanine or aspartic acid, mimicking the fully nonphosphorylated and the fully phosphorylated state of cMyBP-C, respectively...
February 21, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28155608/helical-tomotherapy-versus-conventional-technique-for-post-mastectomy-left-sided-breast-cancer-dosimetric-study
#14
M O Alshabanah, Mohamed Hegazy, Belal Moftah, Mohammad Shabanah
METHODS AND MATERIALS: Treatment plans were generated for 5 post mastectomy left sided breast cancer patients treated at king Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia, comparing three-dimensional technique with the HT planning. The prescribed dose was 50 Gy in 25 fractions; the planning target volume (chest wall and nodal volumes) was contoured according to RTOG atlas and the heart, lungs, spinal cord and contralateral breast were contoured as Organs at Risks (OARs)...
February 1, 2017: Reviews on Recent Clinical Trials
https://www.readbyqxmd.com/read/28129971/dosimetric-aspects-of-breast-radiotherapy-with-three-dimensional-and-intensity-modulated-radiotherapy-helical-tomotherapy-planning-modules
#15
Poonam Yadav, Yue Yan, Tasha Ignatowski, Anna Olson
In this work, we investigated the dosimetric differences between the intensity-modulated radiotherapy (IMRT) plans and the three-dimensional (3D) helical plans based on the TomoTherapy system. A total of 15 patients with supine setup were randomly selected from the data base. For patients with lumpectomy planning target volume (PTV), regional lymph nodes were also included as part of the target. For dose sparing, the significant differences between the helical IMRT and helical 3D were only found in the heart and contralateral breast...
April 2017: Medical Dosimetry: Official Journal of the American Association of Medical Dosimetrists
https://www.readbyqxmd.com/read/28100834/soft-robotic-sleeve-supports-heart-function
#16
Ellen T Roche, Markus A Horvath, Isaac Wamala, Ali Alazmani, Sang-Eun Song, William Whyte, Zurab Machaidze, Christopher J Payne, James C Weaver, Gregory Fishbein, Joseph Kuebler, Nikolay V Vasilyev, David J Mooney, Frank A Pigula, Conor J Walsh
There is much interest in form-fitting, low-modulus, implantable devices or soft robots that can mimic or assist in complex biological functions such as the contraction of heart muscle. We present a soft robotic sleeve that is implanted around the heart and actively compresses and twists to act as a cardiac ventricular assist device. The sleeve does not contact blood, obviating the need for anticoagulation therapy or blood thinners, and reduces complications with current ventricular assist devices, such as clotting and infection...
January 18, 2017: Science Translational Medicine
https://www.readbyqxmd.com/read/28057907/molecular-cloning-and-characterization-of-the-porcine-ribosomal-protein-l21
#17
Wu-Sheng Sun, Ju-Lan Chun, Dong-Hwan Kim, Jin-Seop Ahn, Min-Kyu Kim, In-Sul Hwang, Dae-Jin Kwon, Seong-Soo Hwang, Jeong-Woong Lee
Ribosomal protein L21 (RPL21) is a structural component of the 60S subunit of the eukaryotic ribosome. This protein plays an important role in protein synthesis and the occurrence of hereditary diseases. Pig is a common laboratory model, however, to the best of our knowledge, its RPL21 gene has not been cloned to date. In this study, we cloned and identified the full-length sequence of the pig RPL21 gene for the first time. Then we studied its expression pattern and function by overexpression or knockdown approach...
January 4, 2017: Journal of Veterinary Science
https://www.readbyqxmd.com/read/28047037/su-f-t-435-helical-tomotherapy-for-craniospinal-irradiation-what-we-have-learned-from-a-multi-institutional-study
#18
D Du, C Han, J Chen, A Perez-Andujar, B Lee, T Kaprealian, D Low, X Qi
PURPOSE: To report cranio-spinal irradiation (CSI) planning experience, compare dosimetric quality and delivery efficiency with Tomotherapy from different institutions, and to investigate effect of planning parameters on plan quality and treatment time. METHODS: Clinical helical tomotherapy IMRT plans for thirty-nine CSI cases from three academic institutions were retrospectively evaluated. The planning parameters: field width (FW), pitch, modulation factor (MF), and achieved dosimetric endpoints were cross-compared...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28000164/respiratory-average-ct-for-attenuation-correction-in-myocardial-perfusion-spect-ct
#19
Duo Zhang, Bang-Hung Yang, Nien Yun Wu, Greta Seng Peng Mok
OBJECTIVE: Cine average CT (CACT) and interpolated average CT (IACT) have been proposed to improve attenuation correction (AC) for PET/CT in oncologic and cardiac studies. This study aims to evaluate their effectiveness on myocardial perfusion SPECT/CT using computer simulation and physical phantom experiments. METHODS: We first simulated normal male with (99m)Tc-sestamibi distribution using digital XCAT phantom with respiratory motion amplitudes of 2, 3, and 4 cm...
February 2017: Annals of Nuclear Medicine
https://www.readbyqxmd.com/read/27984146/deciphering-the-interaction-of-bovine-heart-cystatin-with-zno-nanoparticles-spectroscopic-and-thermodynamic-approach
#20
Aamir Sohail, Mohd Faraz, Hussain Arif, Sheraz Ahmad Bhat, Azad Alam Siddiqui, Bilqees Bano
ZnO-NPs have been widely used in biomedical fields such as therapeutics, cellular imaging, and drug delivery. However, the risk of exposure of nanoparticles to the biological system is not well understood. Nanoparticle-protein interaction is pivotal to understand their biological behavior and predict nanoparticle toxicity that is crucial for its safer applications. In the present study zinc oxide nanoparticles (ZnO-NPs) were synthesized and subjected to interact with buffalo heart cystatin (BHC), purified from buffalo heart, to assess the effect(s) of ZnO-NPs on the structure and function of BHC...
February 2017: International Journal of Biological Macromolecules
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