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https://www.readbyqxmd.com/read/28432954/fully-automatic-left-ventricular-segmentation-from-long-axis-cardiac-cine-mr-scans
#1
Rahil Shahzad, Qian Tao, Oleh Dzyubachyk, Marius Staring, Boudewijn P F Lelieveldt, Rob J van der Geest
With an increasing number of large-scale population-based cardiac magnetic resonance (CMR) imaging studies being conducted nowadays, there comes the mammoth task of image annotation and image analysis. Such population-based studies would greatly benefit from automated pipelines, with an efficient CMR image analysis workflow. The purpose of this work is to investigate the feasibility of using a fully-automatic pipeline to segment the left ventricular endocardium and epicardium simultaneously on two orthogonal (vertical and horizontal) long-axis cardiac cine MRI scans...
April 13, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28432822/focal-liver-lesions-segmentation-and-classification-in-nonenhanced-t2-weighted-mri
#2
Ilias Gatos, Stavros Tsantis, Maria Karamesini, Stavros Spiliopoulos, Dimitris Karnabatidis, John D Hazle, George C Kagadis
PURPOSE: To automatically segment and classify focal liver lesions (FLLs) on nonenhanced T2-weighted magnetic resonance imaging (MRI) scans using a computer-aided diagnosis (CAD) algorithm. METHODS: 71 FLLs (30 benign lesions, 19 hepatocellular carcinomas, and 22 metastases) on T2-weighted MRI scans were delineated by the proposed CAD scheme. The FLL segmentation procedure involved wavelet multiscale analysis to extract accurate edge information and mean intensity values for consecutive edges computed using horizontal and vertical analysis that were fed into the subsequent fuzzy C-means algorithm for final FLL border extraction...
April 22, 2017: Medical Physics
https://www.readbyqxmd.com/read/28432777/preparative-isoelectric-focusing-in-a-cellulose-based-separation-medium
#3
Jiří Šalplachta, Marie Horká, Karel Šlais
An improved preparative method based on isoelectric focusing of analytes in a cellulose-based separation medium is described in this study. Cellulose is suspended in an aqueous solution of simple buffers, ethylene glycol, glycerol, nonionic surfactant, and colored pI markers. Water partially evaporates during focusing run and the separation takes place in an in-situ generated layer of cellulose, which has a gel-like appearance at the end of analysis. Final positions of analytes are indicated by the positions of zones of focused pI markers...
April 22, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28432747/whole-body-adipose-tissue-and-lean-muscle-volumes-and-their-distribution-across-gender-and-age-mr-derived-normative-values-in-a-normal-weight-swiss-population
#4
Erika J Ulbrich, Daniel Nanz, Olof Dahlqvist Leinhard, Magda Marcon, Michael A Fischer
PURPOSE: To determine age- and gender-dependent whole-body adipose tissue and muscle volumes in healthy Swiss volunteers in Dixon MRI in comparison with anthropometric and bioelectrical impedance (BIA) measurements. METHODS: Fat-water-separated whole-body 3 Tesla MRI of 80 healthy volunteers (ages 20 to 62 years) with a body mass index (BMI) of 17.5 to 26.2 kg/m(2) (10 men, 10 women per decade). Age and gender-dependent volumes of total adipose tissue (TAT), visceral adipose tissue (VAT), total abdominal subcutaneous adipose tissue (ASAT) and total abdominal adipose tissue (TAAT), and the total lean muscle tissue (TLMT) normalized for body height were determined by semi-automatic segmentation, and correlated with anthropometric and BIA measurements as well as lifestyle parameters...
April 22, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28432698/quantitative-evaluation-of-metal-artifacts-using-different-cbct-devices-high-density-materials-and-field-of-views
#5
Marina Codari, Karla de Faria Vasconcelos, Laura Ferreira Pinheiro Nicolielo, Francisco Haiter Neto, Reinhilde Jacobs
OBJECTIVE: To objectively compare the influence of different cone-beam computed tomography (CBCT) devices, high-density materials and field of views (FOVs) on metal artifact expression. MATERIAL AND METHODS: For this in vitro study, three customized acrylic resin phantoms containing high-density materials cylinders: titanium, copper-aluminum alloy and amalgam were scanned on three CBCT devices using high-resolution protocols, same voxel size (0.2 mm) and different FOVs...
April 22, 2017: Clinical Oral Implants Research
https://www.readbyqxmd.com/read/28432671/investigation-of-the-physical-effects-of-respiratory-motion-compensation-in-a-large-population-of-patients-undergoing-tc-99m-cardiac-perfusion-spect-ct-stress-imaging
#6
P Hendrik Pretorius, Karen L Johnson, Seth T Dahlberg, Michael A King
BACKGROUND: Respiratory motion can deteriorate image fidelity in cardiac perfusion SPECT. We determined the extent of respiratory motion, assessed its impact on image fidelity, and investigated the existence of gender differences, thereby examining the influence of respiratory motion in a large population of patients. METHODS: One thousand one hundred and three SPECT/CT patients underwent visual tracking of markers on their anterior surface during stress acquisition to track respiratory motion...
April 21, 2017: Journal of Nuclear Cardiology: Official Publication of the American Society of Nuclear Cardiology
https://www.readbyqxmd.com/read/28432563/complete-sequences-of-the-rna-1-and-rna-2-segments-of-chronic-bee-paralysis-virus-strain-cbpv-bj-detected-in-china
#7
Beibei Li, Shuai Deng, Dahe Yang, Chunsheng Hou, Qingyun Diao
Chronic bee paralysis virus (CBPV) is an important viral pathogen that affects adult bees. Although several CBPV strains have been reported, little information has been obtained from China. In this study, two major segments of the CBPV Chinese isolate CBPV-BJ, RNA 1 and RNA 2, were determined to be 3657 and 2267 nucleotides (nt) in length, respectively. RNA 1 and RNA 2 contained three and four open reading frames (ORFs), respectively, which agreed with known reference strains (EU122229 and EU122230). The RNA 1 had 98% nucleotide sequence identity to a known Chinese strain (KU950353), and RNA 2 had 97% nucleotide sequence identity to another Chinese strain (KU950354)...
April 21, 2017: Archives of Virology
https://www.readbyqxmd.com/read/28432503/high-voltage-zones-within-the-pulmonary-vein-antra-major-determinants-of-acute-pulmonary-vein-reconnections-after-atrial-fibrillation-ablation
#8
Koichi Nagashima, Ichiro Watanabe, Yasuo Okumura, Kazuki Iso, Keiko Takahashi, Ryuta Watanabe, Masaru Arai, Sayaka Kurokawa, Toshiko Nakai, Kimie Ohkubo, Shunichi Yoda, Atsushi Hirayama
PURPOSE: Recurrence of atrial fibrillation (AF) after pulmonary vein isolation (PVI) is mainly due to PV reconnections. Patient-specific tissue characteristics that may contribute remain unidentified. This study aimed to assess the relationship between the bipolar electrogram voltage amplitudes recorded from the PV-left atrial (LA) junction and acute PV reconnection sites. METHODS: Three-dimensional LA voltage maps created before an extensive encircling PVI in 47 AF patients (31 men; mean age 62 ± 11 years) were examined for an association between the EGM voltage amplitude recorded from the PV-LA junction and acute post-PVI PV reconnections (spontaneous PV reconnections and/or ATP-provoked dormant PV conduction)...
April 21, 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
https://www.readbyqxmd.com/read/28432489/design-development-and-clinical-validation-of-computer-aided-surgical-simulation-system-for-streamlined-orthognathic-surgical-planning
#9
REVIEW
Peng Yuan, Huaming Mai, Jianfu Li, Dennis Chun-Yu Ho, Yingying Lai, Siting Liu, Daeseung Kim, Zixiang Xiong, David M Alfi, John F Teichgraeber, Jaime Gateno, James J Xia
PURPOSE: There are many proven problems associated with traditional surgical planning methods for orthognathic surgery. To address these problems, we developed a computer-aided surgical simulation (CASS) system, the AnatomicAligner, to plan orthognathic surgery following our streamlined clinical protocol. METHODS: The system includes six modules: image segmentation and three-dimensional (3D) reconstruction, registration and reorientation of models to neutral head posture, 3D cephalometric analysis, virtual osteotomy, surgical simulation, and surgical splint generation...
April 21, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28432452/fluorescent-angioscopic-imaging-of-calcium-phosphate-tribasic-precursor-of-hydroxyapatite-the-major-calcium-deposit-in-human-coronary-plaques
#10
Takanobu Kobayashi, Osamu Nakagawa, Seiichiro Shirai, Ei Shimoyama, Nobuyuki Hiruta, Yasumi Uchida
Coronary calcification is a risk factor for ischemic heart disease. Hydroxyapatite that is formed by polymerization from calcium phosphate tribasic (CPT) is the major constituent of coronary calcium deposits. If CPT could be visualized, coronary calcification could be predicted and prevented. We discovered that when CPT and collagen I, the main constituent of collagen fibers, are mixed with lac dye (LD) and then exposed to fluorescent light excited at 345 ± 15 nm and emitted at 420 nm, a purple fluorescence that is characteristic of CPT only is elicited...
April 21, 2017: International Journal of Cardiovascular Imaging
https://www.readbyqxmd.com/read/28432346/functionally-interchangeable-cis-acting-rna-elements-in-both-genome-segments-of-a-picorna-like-plant-virus
#11
Jiangbo Guo, Junping Han, Junyan Lin, John Finer, Anne Dorrance, Feng Qu
Cis-acting RNA structures in the genomes of RNA viruses play critical roles in viral infection, yet their importance in the bipartite genomes of the picorna-like, plant-infecting comoviruses has not been carefully investigated. We previously characterized SLC, a stem-loop structure in the 5' untranslated region (UTR) of the bean pod mottle comovirus (BPMV) RNA2, and found it to be essential for RNA2 accumulation in infected cells. Here we report the identification of SL1, a similar cis-acting element in the other BPMV genome segment - RNA1...
April 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28432218/dynamics-of-growth-zone-patterning-in-the-milkweed-bug-oncopeltus-fasciatus
#12
Tzach Auman, Barbara M I Vreede, Aryeh Weiss, Susan D Hester, Terri A Williams, Lisa M Nagy, Ariel D Chipman
We describe the dynamic process of abdominal segment generation in the milkweed bug Oncopeltus fasciatus We present detailed morphological measurements of the growing germband throughout segmentation. Our data are complemented by cell division profiles and expression patterns of key genes, including invected and even-skipped as markers for different stages of segment formation. We describe morphological and mechanistic changes in the growth zone and in nascent segments during generation of individual segments and throughout segmentation, and examine the relative contribution of newly formed versus existing tissue to segment formation...
April 21, 2017: Development
https://www.readbyqxmd.com/read/28432194/diagnostic-value-of-prehospital-ecg-in-acute-stroke-patients
#13
Tobias Bobinger, Bernd Kallmünzer, Markus Kopp, Natalia Kurka, Martin Arnold, Stefan Heider, Stefan Schwab, Martin Köhrmann
OBJECTIVE: To investigate the diagnostic yield of prehospital ECG monitoring provided by emergency medical services in the case of suspected stroke. METHODS: Consecutive patients with acute stroke admitted to our tertiary stroke center via emergency medical services and with available prehospital ECG were prospectively included during a 12-month study period. We assessed prehospital ECG recordings and compared the results to regular 12-lead ECG on admission and after continuous ECG monitoring at the stroke unit...
April 21, 2017: Neurology
https://www.readbyqxmd.com/read/28432188/magnetic-resonance-neurography-visualizes-abnormalities-in-sciatic-and-tibial-nerves-in-patients-with-type-1-diabetes-and-neuropathy
#14
Michael Vaeggemose, Mirko Pham, Steffen Ringgaard, Hatice Tankisi, Niels Ejskjaer, Sabine Heiland, Per L Poulsen, Henning Andersen
This study evaluates whether diffusion-tensor-imaging MR-Neurography (DTI-MRN), T2-relaxation-time and proton-spin-density can detect and grade neuropathic abnormalities in patients with type 1 diabetes.Forty-nine patients with type 1 diabetes (11 with severe polyneuropathy (sDPN), 13 with mild polyneuropathy (mDPN) and 25 without polyneuropathy (nDPN)) and 30 healthy controls (HC) were included. Clinical examinations, nerve-conduction-studies and vibratory-perception-thresholds determined the presence and severity of DPN...
April 21, 2017: Diabetes
https://www.readbyqxmd.com/read/28432144/age-related-effects-and-sex-differences-in-gray-matter-density-volume-mass-and-cortical-thickness-from-childhood-to-young-adulthood
#15
Efstathios D Gennatas, Brian B Avants, Daniel H Wolf, Theodore D Satterthwaite, Kosha Ruparel, Rastko Ciric, Hakon Hakonarson, Raquel E Gur, Ruben C Gur
Developmental structural neuroimaging studies in humans have long described decreases in gray matter volume and cortical thickness during adolescence. Gray matter density, a measure often assumed to be highly related to volume, has not been systematically investigated in development. We used T1 imaging data collected on the Philadelphia Neurodevelopmental Cohort to study age-related effects and sex differences in four regional gray matter measures in 1189 youths aged 8 to 23 years. Custom T1 segmentation and a novel high-resolution gray matter parcellation were used to extract gray matter density (GMD), gray matter volume (GMV), gray matter mass (GMM, defined as GMD * GMV), and cortical thickness (CT) from 1625 brain regions...
April 21, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28432123/an-amphipathic-%C3%AE-helix-directs-palmitoylation-of-the-large-intracellular-loop-of-the-sodium-calcium-exchanger
#16
Fiona Plain, Samitha Dilini Congreve, Rachel Sue Zhen Yee, Jennifer Kennedy, Jacqueline Howie, Chien-Wen Kuo, Niall Fraser, William Fuller
The electrogenic sodium/calcium exchanger (NCX) mediates bidirectional calcium transport controlled by the transmembrane sodium gradient. NCX inactivation occurs in the absence of phosphatidylinositol 4,5-bisphosphate (PIP2), and is facilitated by palmitoylation of a single cysteine at position 739 within NCX's large intracellular loop. The aim of this investigation was to identify the structural determinants of NCX1 palmitoylation. Full-length NCX1 (FL-NCX1) and a YFP fusion protein of the NCX1 large intracellular loop (YFP-NCX1) were expressed in HEK cells...
April 21, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28432113/automated-quantitative-characterisation-of-retinal-vascular-leakage-and-microaneurysms-in-ultra-widefield-fluorescein-angiography
#17
Justis P Ehlers, Kevin Wang, Amit Vasanji, Ming Hu, Sunil K Srivastava
Ultra-widefield fluorescein angiography (UWFA) is an emerging imaging modality used to characterise pathology in the retinal vasculature such as microaneurysms (MAs) and vascular leakage. Despite its potential value for diagnosis and disease surveillance, objective quantitative assessment of retinal pathology by UWFA is currently limited because it requires laborious manual segmentation by trained human graders. In this report, we describe a novel fully automated software platform, which segments MAs and leakage areas in native and dewarped UWFA images with retinal vascular disease...
April 21, 2017: British Journal of Ophthalmology
https://www.readbyqxmd.com/read/28432110/anterior-but-not-posterior-choroid-changed-before-and-during-valsalva-manoeuvre-in-healthy-chinese-a-ubm-and-ss-oct-study
#18
Fei Li, Kai Gao, Xingyi Li, Shida Chen, Wenbin Huang, Xiulan Zhang
PURPOSE: To determine if the anterior choroid is involved in ocular change during the Valsalva manoeuvre (VM). MATERIALS AND METHODS: Fifty-three healthy volunteers aged 18-65 years with normal visual field test results and no history of intraocular pressure (IOP) exceeding 21 mm Hg were recruited. Anterior and posterior choroidal changes before and during VM were recorded by ultrasound microscope and swept-source optical coherence tomography, respectively. Parameters of the anterior segment included ciliary body thickness (CBT0), thickness of the choroid at a distance of 4 mm from the root of the iris (CT4), anterior placement of the ciliary body (APCB) and trabecular-ciliary angle (TCA)...
April 21, 2017: British Journal of Ophthalmology
https://www.readbyqxmd.com/read/28431955/the-course-of-modic-vertebral-body-changes-after-posterolateral-lumbar-fusion-on-fused-and-adjacent-levels-a-systematic-review-of-the-literature
#19
REVIEW
Stella Taylor Portella, Marcus André Acioly
According to the original description by Modic et al., the natural course of bone marrow signal abnormalities is an inexorable, progressive one, however recent evidence has demonstrated in healthy individuals and those suffering from lumbar disc herniation that the course of endplate degenerative changes is rather dynamic and sometimes regressive. The evolution of such changes in lumbar fused segments and adjacent levels is largely unknown. The literature relevant to the course of Modic changes on fused and adjacent levels, as well as its clinical correspondence in patients undergoing posterolateral lumbar fusion was collected...
April 18, 2017: Journal of Clinical Neuroscience: Official Journal of the Neurosurgical Society of Australasia
https://www.readbyqxmd.com/read/28431954/isolated-intracranial-fibromuscular-dysplasia-of-the-posterior-cerebral-artery
#20
Min-Ju Yeo, Ho-Yeong Jeon, Min-Ju Cha, Hye-Yeon Jang, Sang-Gil Lee, Ji Seon Kim, Sung-Hyun Lee, Sang-Soo Lee, Dong-Ick Shin
Fibromuscular dysplasia (FMD) is a nonatherosclerotic, noninflammatory arterial disease that most commonly affects the renal and internal carotid arteries, but intracranial FMD is very rare. We report a patient with FMD involving the posterior cerebral arteries (PCAs). A 24year old female was presented with a 4day history of right homonymous hemianopsia with throbbing headache in the left temporo-occipital area. The brain magnetic resonance imaging (MRI) revealed an acute ischemic stroke in the left PCA territory, while the Time of Flight (TOF) magnetic resonance angiogram (MRA) showed segmental luminal irregularities in the left proximal PCA...
April 18, 2017: Journal of Clinical Neuroscience: Official Journal of the Neurosurgical Society of Australasia
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