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https://www.readbyqxmd.com/read/28339670/exploring-the-variability-in-beh%C3%A3-et-s-disease-prevalence-a-meta-analytical-approach
#1
Carla Maldini, Katie Druce, Neil Basu, Michael P LaValley, Alfred Mahr
Background.: Surveys of Behçet's disease (BD) have shown substantial geographic variations in prevalence, but some of these differences may result from methodological inconsistencies. This meta-analysis explored the effect of geographic location and study methodology on the prevalence of BD. Methods.: We systematically searched the literature in electronic databases and by handsearching to identify population-based prevalence surveys of BD. Studies were eligible if they provided an original population-based prevalence estimate for BD with the number of prevalent cases identified in the study area...
February 17, 2017: Rheumatology
https://www.readbyqxmd.com/read/28335211/noise-removal-with-maintained-spatial-resolution-in-raman-images-of-cells-exposed-to-submicron-polystyrene-particles
#2
Linnea Ahlinder, Susanne Wiklund Lindström, Christian Lejon, Paul Geladi, Lars Österlund
The biodistribution of 300 nm polystyrene particles in A549 lung epithelial cells has been studied with confocal Raman spectroscopy. This is a label-free method in which particles and cells can be imaged without using dyes or fluorescent labels. The main drawback with Raman imaging is the comparatively low spatial resolution, which is aggravated in heterogeneous systems such as biological samples, which in addition often require long measurement times because of their weak Raman signal. Long measurement times may however induce laser-induced damage...
April 29, 2016: Nanomaterials
https://www.readbyqxmd.com/read/28334963/three-and-four-dimensional-mapping-of-speech-and-language-in-patients-with-epilepsy
#3
Yasuo Nakai, Jeong-Won Jeong, Erik C Brown, Robert Rothermel, Katsuaki Kojima, Toshimune Kambara, Aashit Shah, Sandeep Mittal, Sandeep Sood, Eishi Asano
We have provided 3-D and 4D mapping of speech and language function based upon the results of direct cortical stimulation and event-related modulation of electrocorticography signals. Patients estimated to have right-hemispheric language dominance were excluded. Thus, 100 patients who underwent two-stage epilepsy surgery with chronic electrocorticography recording were studied. An older group consisted of 84 patients at least 10 years of age (7367 artefact-free non-epileptic electrodes), whereas a younger group included 16 children younger than age 10 (1438 electrodes)...
March 16, 2017: Brain: a Journal of Neurology
https://www.readbyqxmd.com/read/28334577/on-the-achievable-field-sensitivity-of-a-segmented-annular-detector-for-differential-phase-contrast-measurements
#4
Felix Schwarzhuber, Peter Melzl, Josef Zweck
Differential phase contrast microscopy measures minute deflections of the electron probe due to electric and/or magnetic fields, using a position sensitive device. Although recently, pixelated detectors have become available which also serve as a position sensitive device, the most frequently used detector is a four-segmented annular semiconducting detector ring (or variations thereof), where the difference signals of opposing detector elements represent the components of the deflection vector. This deflection vector can be used directly to quantitatively determine the deflecting field, provided the specimen's thickness is known...
March 4, 2017: Ultramicroscopy
https://www.readbyqxmd.com/read/28331947/-magnetic-resonance-spectroscopy-of-brain-tumors
#5
P Ditter, E Hattingen
BACKGROUND: Conventional magnetic resonance imaging (MRI) under consideration of clinical information enables the correct diagnosis and therapy for the majority of cerebral space-occupying lesions. Some important differential diagnoses, e. g. low vs. high-grade tumors, require additional MRI methods. OBJECTIVE: This article critically discusses the importance of magnetic resonance spectroscopy ((1)H-MRS) in brain tumors. MATERIAL AND METHODS: The concentration of normal and pathological brain metabolites can be non-invasively measured by (1)H-MRS...
March 22, 2017: Der Radiologe
https://www.readbyqxmd.com/read/28329889/masking-artefact-indicates-that-photoreceptor-bleaching-may-enhance-fundus-autofluorescence
#6
G M Somfai, D C DeBuc, H Gerding
No abstract text is available yet for this article.
March 22, 2017: Klinische Monatsblätter Für Augenheilkunde
https://www.readbyqxmd.com/read/28329634/comparing-survival-of-patients-with-single-or-multiple-primary-melanoma-in-the-netherlands-1994-2009
#7
L M Pardo, R J T Ven der Leest, E De Vries, I Soerjomataram, T Nijsten, L M Hollestein
There is conflicting literature as to whether the survival of patients with multiple melanoma is worse that this of single melanoma cases. We used extended Cox-proportional hazard models to estimate hazard-ratios (HR) of patients with multiple melanomas against single melanomas. Data from the nationwide Dutch Cancer Registry was used to retrieve cutaneous melanoma cases between 1994 and 2009 and linked with municipal records to assess the vital status. To account for the longer survival in the multiple melanoma cases we modelled multiple melanoma as time-varying variable, as well as Breslow thickness, histological subtype and nodal/distant metastasis...
September 15, 2016: Dermatology Online Journal
https://www.readbyqxmd.com/read/28329342/the-aureole-sign-a-rare-echocardiographic-artefact
#8
Matthias Schneider, Thomas Binder, Gerald Maurer, Irene Lang, Georg Goliasch
No abstract text is available yet for this article.
March 9, 2017: European Heart Journal Cardiovascular Imaging
https://www.readbyqxmd.com/read/28328030/estimation-of-microscope-drift-using-fluorescent-nanodiamonds-as-fiducial-markers
#9
W Colomb, J Czerski, J D Sau, S K Sarkar
Fiducial markers are used to correct the microscope drift and should be photostable, be usable at multiple wavelengths and be compatible for multimodal imaging. Fiducial markers such as beads, gold nanoparticles, microfabricated patterns and organic fluorophores lack one or more of these criteria. Moreover, the localization accuracy and drift correction can be degraded by other fluorophores, instrument noise and artefacts due to image processing and tracking algorithms. Estimating mechanical drift by assuming Gaussian distributed noise is not suitable under these circumstances...
March 22, 2017: Journal of Microscopy
https://www.readbyqxmd.com/read/28326168/ribonucleic-artefacts-are-some-extracellular-rna-discoveries-driven-by-cell-culture-medium-components
#10
REVIEW
Juan Pablo Tosar, Alfonso Cayota, Erez Eitan, Marc K Halushka, Kenneth W Witwer
In a recently published study, Anna Krichevsky and colleagues raise the important question of whether results of in vitro extracellular RNA (exRNA) studies, including extracellular vesicle (EV) investigations, are confounded by the presence of RNA in cell culture medium components such as foetal bovine serum (FBS). The answer, according to their data, is a resounding "yes". Even after lengthy ultracentrifugation to remove bovine EVs from FBS, the majority of exRNA in FBS remained. Although technical factors may affect the degree of depletion, residual EVs and exRNA in FBS could influence the conclusions of in vitro studies: certainly, for secreted RNA, and possibly also for cell-associated RNA...
2017: Journal of Extracellular Vesicles
https://www.readbyqxmd.com/read/28325448/diagnosis-of-autism-through-eeg-processed-by-advanced-computational-algorithms-a-pilot-study
#11
Enzo Grossi, Chiara Olivieri, Massimo Buscema
BACKGROUND: Multi-Scale Ranked Organizing Map coupled with Implicit Function as Squashing Time algorithm(MS-ROM/I-FAST) is a new, complex system based on Artificial Neural networks (ANNs) able to extract features of interest in computerized EEG through the analysis of few minutes of their EEG without any preliminary pre-processing. A proof of concept study previously published showed accuracy values ranging from 94%-98% in discerning subjects with Mild Cognitive Impairment and/or Alzheimer's Disease from healthy elderly people...
April 2017: Computer Methods and Programs in Biomedicine
https://www.readbyqxmd.com/read/28324943/overcoming-spatio-temporal-limitations-using-dynamically-scaled-in-vitro-pc-mri-a-flow-field-comparison-to-true-scale-computer-simulations-of-idealized-stented-and-patient-specific-left-main-bifurcations
#12
Susann Beier, John Ormiston, Mark Webster, John Cater, Stuart Norris, Pau Medrano-Gracia, Alistair Young, Kathleen Gilbert, Brett Cowan
The majority of patients with angina or heart failure have coronary artery disease. Left main bifurcations are particularly susceptible to pathological narrowing. Flow is a major factor of atheroma development, but limitations in imaging technology such as spatio-temporal resolution, signal-to-noise ratio (SNRv), and imaging artefacts prevent in vivo investigations. Computational fluid dynamics (CFD) modelling is a common numerical approach to study flow, but it requires a cautious and rigorous application for meaningful results...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28323852/extraction-of-features-from-sleep-eeg-for-bayesian-assessment-of-brain-development
#13
Vitaly Schetinin, Livija Jakaite
Brain development can be evaluated by experts analysing age-related patterns in sleep electroencephalograms (EEG). Natural variations in the patterns, noise, and artefacts affect the evaluation accuracy as well as experts' agreement. The knowledge of predictive posterior distribution allows experts to estimate confidence intervals within which decisions are distributed. Bayesian approach to probabilistic inference has provided accurate estimates of intervals of interest. In this paper we propose a new feature extraction technique for Bayesian assessment and estimation of predictive distribution in a case of newborn brain development assessment...
2017: PloS One
https://www.readbyqxmd.com/read/28317596/life-cycle-assessment-in-solid-waste-management-facts-and-artefacts
#14
EDITORIAL
Dimitrios Komilis, Antoni Sánchez Ferrer
No abstract text is available yet for this article.
March 2017: Waste Management
https://www.readbyqxmd.com/read/28316055/a-comparison-of-accelerated-and-non-accelerated-mri-scans-for-brain-volume-and-boundary-shift-integral-measures-of-volume-change-evidence-from-the-adni-dataset
#15
Emily N Manning, Kelvin K Leung, Jennifer M Nicholas, Ian B Malone, M Jorge Cardoso, Jonathan M Schott, Nick C Fox, Josephine Barnes
The aim of this study was to assess whether the use of accelerated MRI scans in place of non-accelerated scans influenced brain volume and atrophy rate measures in controls and subjects with mild cognitive impairment and Alzheimer's disease. We used data from 861 subjects at baseline, 573 subjects at 6 months and 384 subjects at 12 months from the Alzheimer's Disease Neuroimaging Initiative (ADNI). We calculated whole-brain, ventricular and hippocampal atrophy rates using the k-means boundary shift integral (BSI)...
March 18, 2017: Neuroinformatics
https://www.readbyqxmd.com/read/28299895/deep-sequencing-and-variant-analysis-of-an-italian-pathogenic-field-strain-of-equine-infectious-anaemia-virus
#16
K Cappelli, R F Cook, V Stefanetti, F Passamonti, G L Autorino, M T Scicluna, M Coletti, A Verini Supplizi, S Capomaccio
Equine infectious anaemia virus (EIAV) is a lentivirus with an almost worldwide distribution that causes persistent infections in equids. Technical limitations have restricted genetic analysis of EIAV field isolates predominantly to gag sequences resulting in very little published information concerning the extent of inter-strain variation in pol, env and the three ancillary open reading frames (ORFs). Here, we describe the use of long-range PCR in conjunction with next-generation sequencing (NGS) for rapid molecular characterization of all viral ORFs and known transcription factor binding motifs within the long terminal repeat of two EIAV isolates from the 2006 Italian outbreak...
March 15, 2017: Transboundary and Emerging Diseases
https://www.readbyqxmd.com/read/28295403/toward-a-3d-transrectal-ultrasound-system-for-verification-of-needle-placement-during-high-dose-rate-interstitial-gynecologic-brachytherapy
#17
Jessica Robin Rodgers, Kathleen Surry, Eric Leung, David D'Souza, Aaron Fenster
PURPOSE: Treatment for gynecologic cancers, such as cervical, recurrent endometrial, and vaginal malignancies, commonly includes external-beam radiation and brachytherapy. In high-dose-rate (HDR) interstitial gynecologic brachytherapy, radiation treatment is delivered via hollow needles that are typically inserted through a template on the perineum with a cylinder placed in the vagina for stability. Despite the need for precise needle placement to minimize complications and provide optimal treatment, there is no standard intra-operative image-guidance for this procedure...
March 15, 2017: Medical Physics
https://www.readbyqxmd.com/read/28287428/an-experimental-study-of-the-effects-of-external-physiological-parameters-on-the-photoplethysmography-signals-in-the-context-of-local-blood-pressure-hydrostatic-pressure-changes
#18
Hongwei Yuan, Sven Poeggel, Thomas Newe, Elfed Lewis, Charusluk Viphavakit, Gabriel Leen
A comprehensive study of the effect of a wide range of controlled human subject motion on Photoplethysmographic signals is reported. The investigation includes testing of two separate groups of 5 and 18 subjects who were asked to undertake set exercises whilst simultaneously monitoring a wide range of physiological parameters including Breathing Rate, Heart Rate and Localised Blood Pressure using commercial clinical sensing systems. The unique finger mounted PPG probe equipped with miniature three axis accelerometers for undertaking this investigation was a purpose built in-house version which is designed to facilitate reproducible application to a wide range of human subjects and the study of motion...
March 10, 2017: Sensors
https://www.readbyqxmd.com/read/28286999/an-assessment-of-the-importance-ofexposure-routes-to-the-uptake-and-internal-localisation-of-fluorescent-nanoparticles-in-zebrafish-danio-rerio-using-light-sheet-microscopy
#19
L M Skjolding, G Ašmonaitė, R I Jølck, T L Andresen, H Selck, A Baun, J Sturve
A major challenge in nanoecotoxicology is finding suitable methods to determine the uptake and localisation of nanoparticles on a whole-organism level. Some uptake methods have been associated with artefacts induced by sample preparation, including staining for electron microscopy. This study used light sheet microscopy (LSM) to define the uptake and localisation of fluorescently labelled nanoparticles in living organisms with minimal sample preparation. Zebrafish (Danio rerio) were exposed to fluorescent gold nanoparticles (Au NPs) and fluorescent polystyrene NPs via aqueous or dietary exposure...
March 11, 2017: Nanotoxicology
https://www.readbyqxmd.com/read/28286687/lipomatous-extensively-vacuolated-ependymoma-with-signet-ring-cell-like-appearance-analysis-of-a-case-with-extensive-literature-review
#20
Miguel Fdo Salazar, Martha Lilia Tena-Suck, Alma Ortiz-Plata, Citlaltepetl Salinas-Lara, Daniel Rembao-Bojórquez
"Lipomatous" and "extensively vacuolated" are descriptive captions that have been used to portray a curious subset of ependymomas distinctively bearing cells with a large vacuole pushing the nucleus to the periphery and, thus, simulating a signet-ring cell appearance. Here, we would like to report the first ependymoma of this kind in a Latin American institution. A 16-year-old boy experienced cephalea during three months. Magnetic resonance imaging scans showed a left paraventricular tumour which corresponded to anaplastic ependymoma...
2017: Case Reports in Pathology
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