keyword
MENU ▼
Read by QxMD icon Read
search

“magnetic resonance”

keyword
https://www.readbyqxmd.com/read/29783186/-1-h-nmr-and-uplc-ms-metabolomics-functional-tools-for-exploring-chemotypic-variation-in-sceletium-tortuosum-from-two-provinces-in-south-africa
#1
Jianping Zhao, Ikhlas A Khan, Sandra Combrinck, Maxleene Sandasi, Weiyang Chen, Alvaro M Viljoen
Sceletium tortuosum (Aizoaceae) is widely recognised for the treatment of stress, anxiety and depression, as well as for obsessive compulsive disorders. A comprehensive intraspecies chemotypic variation study, using samples harvested from two distinct regions of South Africa, was done using both proton nuclear magnetic resonance (1 H-NMR) spectroscopy of methanol extracts (N = 145) and ultra performance liquid chromatography-mass spectrometry (UPLC-MS) of acid/base extracts (N = 289). Chemometric analysis of the 1 H-NMR data indicated two main clusters that were region-specific (Northern Cape and Western Cape provinces)...
May 17, 2018: Phytochemistry
https://www.readbyqxmd.com/read/29783125/contralateral-functional-reorganization-of-the-speech-supplementary-motor-area-following-neurosurgical-tumor-resection
#2
Srinivas Chivukula, Brian K Pikul, Keith L Black, Nader Pouratian, Susan Y Bookheimer
We evaluated plasticity in speech supplemental motor area (SMA) tissue in two patients using functional magnetic resonance imaging (fMRI), following resection of tumors in or associated with the dominant hemisphere speech SMA. Patient A underwent resection of a anaplastic astrocytoma NOS associated with the left speech SMA, experienced SMA syndrome related mutism postoperatively, but experienced full recovery 14 months later. FMRI performed 32 months after surgery demonstrated a migration of speech SMA to homologous contralateral hemispheric regional tissue...
May 18, 2018: Brain and Language
https://www.readbyqxmd.com/read/29783076/disrupted-reward-and-cognitive-control-networks-contribute-to-anhedonia-in-depression
#3
Liang Gong, Cancan He, Haisan Zhang, Hongxing Zhang, Zhijun Zhang, Chunming Xie
Neuroimaging studies have identified that anhedonia, a core feature of major depressive disorder (MDD), is associated with dysfunction in reward and cognitive control processing. However, it is still not clear how the reward network (β-network) and the cognitive control network (δ-network) are linked to biased anhedonia in MDD patients. Sixty-eight MDD patients and 64 cognitively normal (CN) subjects underwent a resting-state functional magnetic resonance imaging scan. A 2*2 ANCOVA analysis was used to explore the differences in the nucleus accumbens-based, voxelwise functional connectivity (FC) between the groups...
May 12, 2018: Journal of Psychiatric Research
https://www.readbyqxmd.com/read/29782993/generalized-recurrent-neural-network-accommodating-dynamic-causal-modeling-for-functional-mri-analysis
#4
Yuan Wang, Yao Wang, Yvonne W Lui
Dynamic Causal Modeling (DCM) is an advanced biophysical model which explicitly describes the entire process from experimental stimuli to functional magnetic resonance imaging (fMRI) signals via neural activity and cerebral hemodynamics. To conduct a DCM study, one needs to represent the experimental stimuli as a compact vector-valued function of time, which is hard in complex tasks such as book reading and natural movie watching. Deep learning provides the state-of-the-art signal representation solution, encoding complex signals into compact dense vectors while preserving the essence of the original signals...
May 18, 2018: NeuroImage
https://www.readbyqxmd.com/read/29782824/apoe-%C3%AE%C2%B54-associates-with-hippocampal-volume-learning-and-memory-across-the-spectrum-of-alzheimer-s-disease-and-dementia-with-lewy-bodies
#5
Usman Saeed, Saira S Mirza, Bradley J MacIntosh, Nathan Herrmann, Julia Keith, Joel Ramirez, Sean M Nestor, Qinggang Yu, Jo Knight, Walter Swardfager, Steven G Potkin, Ekaterina Rogaeva, Peter St George-Hyslop, Sandra E Black, Mario Masellis
INTRODUCTION: Although the apolipoprotein E ε4-allele (APOE-ε4) is a susceptibility factor for Alzheimer's disease (AD) and dementia with Lewy bodies (DLB), its relationship with imaging and cognitive measures across the AD/DLB spectrum remains unexplored. METHODS: We studied 298 patients (AD = 250, DLB = 48; 38 autopsy confirmed; NCT01800214) using neuropsychological testing, volumetric magnetic resonance imaging, and APOE genotyping to investigate the association of APOE-ε4 with hippocampal volume and learning/memory phenotypes, irrespective of diagnosis...
May 18, 2018: Alzheimer's & Dementia: the Journal of the Alzheimer's Association
https://www.readbyqxmd.com/read/29782823/changing-the-site-energy-of-per-614-in-the-peridinin-chlorophyll-a-protein-does-not-alter-its-capability-of-chlorophyll-triplet-quenching
#6
Alessandro Agostini, Jens Niklas, Tim Schulte, Marilena Di Valentin, Marco Bortolus, Eckhard Hofmann, Wolfgang Lubitz, Donatella Carbonera
The peridinin-chlorophyll-a protein (PCP) is a water-soluble light harvesting protein of the dinoflagellate Amphidinium carterae, employing peridinin (Per) as the main carotenoid to fulfil light harvesting and photo-protective functions. Per molecules bound to the protein experience specific molecular surroundings which lead to different electronic and spectral properties. In the refolded N89 L variant PCP (N89 L-RFPCP) a significant part of the intensity on the long wavelength side of the absorption spectrum is shifted to shorter wavelengths due to a significant change in the Per-614 site energy...
May 18, 2018: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/29782818/antimicrobial-activity-profiles-of-amphiphilic-xanthone-derivatives-are-a-function-of-their-molecular-oligomerization
#7
Jun-Jie Koh, Shuimu Lin, Yang Bai, Wendy Wan Ling Sin, Thet Tun Aung, Jianguo Li, Verma Chandra, Konstantin Pervushin, Roger W Beuerman, Shouping Liu
Currently, membrane-targeting small antimicrobial peptidomimetics (SAP) are important in antibiotic development because bacteria appear to develop resistance to these surface-active compounds less readily. However, the molecular membrane-targeting action of SAPs has received little attention. In this study, we investigated the effect of oligomerization of amphiphilic xanthone, a model SAP, on its antimicrobial properties against both Gram-positive and Gram-negative bacteria. First, oligomer formation by an amphiphilic xanthone, compound 2 (also coded as AM052), was investigated via solution-state nuclear magnetic resonance (NMR) spectroscopy...
May 18, 2018: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/29782639/sudden-cardiac-death-in-athletes-and-the-value-of-cardiovascular-magnetic-resonance
#8
REVIEW
Sophie I Mavrogeni, Flora Bacopoulou, Despoina Apostolaki, George P Chrousos
Sudden cardiac death (SCD) is the non-traumatic death, due to loss of heart function that occurs suddenly and unexpectedly within 6 hours of a previously normal state of health. It is related to intense competitive sports promoting ventricular tachycardia (VT)/ventricular fibrillation (VF) in the presence of underlying abnormal substrate. A serial evaluation of cardiac physiologic changes taking place during training will allow the better understanding of athlete's heart and will facilitate its discrimination from other gray-zone cardiomyopathies...
May 21, 2018: European Journal of Clinical Investigation
https://www.readbyqxmd.com/read/29782617/patient-specific-neurosurgical-phantom-assessment-of-visual-quality-accuracy-and-scaling-effects
#9
Felipe Wilker Grillo, Victor Hugo Souza, Renan Hiroshi Matsuda, Carlo Rondinoni, Theo Zeferino Pavan, Oswaldo Baffa, Helio Rubens Machado, Antonio Adilton Oliveira Carneiro
Background: Training in medical education depends on the availability of standardized materials that can reliably mimic the human anatomy and physiology. One alternative to using cadavers or animal bodies is to employ phantoms or mimicking devices. Styrene-ethylene/butylene-styrene (SEBS) gels are biologically inert and present tunable properties, including mechanical properties that resemble the soft tissue. Therefore, SEBS is an alternative to develop a patient-specific phantom, that provides real visual and morphological experience during simulation-based neurosurgical training...
2018: 3D Print Med
https://www.readbyqxmd.com/read/29782513/high-red-blood-cell-composition-in-clots-is-associated-with-successful-recanalization-during-intra-arterial-thrombectomy
#10
Jong Wook Shin, Hye Seon Jeong, Hyon-Jo Kwon, Kyu Sang Song, Jei Kim
We evaluated the composition of individual clots retrieved during intra-arterial thrombectomy in relation to recanalization success, stroke subtype, and the presence of clot signs on initial brain images. We analyzed clot and interventional data from 145 retrieval trials performed for 37 patients (69.5±14.0 years, 20 men, large artery atherosclerosis, n = 7; cardioembolism, n = 22; undetermined etiology, n = 8) who had undergone intra-arterial thrombectomy. Rates of clot retrieval and successful recanalization (Arterial Occlusive Lesion score of 2-3) for separate retrieval trials were evaluated...
2018: PloS One
https://www.readbyqxmd.com/read/29782510/individual-differences-in-learning-correlate-with-modulation-of-brain-activity-induced-by-transcranial-direct-current-stimulation
#11
Brian Falcone, Atsushi Wada, Raja Parasuraman, Daniel E Callan
Transcranial direct current stimulation (tDCS) has been shown to enhance cognitive performance on a variety of tasks. It is hypothesized that tDCS enhances performance by affecting task related cortical excitability changes in networks underlying or connected to the site of stimulation facilitating long term potentiation. However, many recent studies have called into question the reliability and efficacy of tDCS to induce modulatory changes in brain activity. In this study, our goal is to investigate the individual differences in tDCS induced modulatory effects on brain activity related to the degree of enhancement in performance, providing insight into this lack of reliability...
2018: PloS One
https://www.readbyqxmd.com/read/29782425/increased-arterial-stiffness-in-a-cohort-of-pediatric-takayasu-arteritis-patients-in-toronto-adversely-affects-left-ventricular-mechanics
#12
Heynric B Grotenhuis, Florence A Aeschlimann, Wei Hui, Cameron Slorach, Rae S M Yeung, Susanne M Benseler, Timothy J Bradley, Lars Grosse-Wortmann
BACKGROUND/OBJECTIVE: Takayasu arteritis (TA) is characterized by extensive aortic, large and midsize arterial wall inflammation. The aim of this study was to assess the morphological and elastic properties of the aorta and large arteries and the impact on left ventricular (LV) mechanics in children with TA. METHODS: Seven pediatric TA patients (6 female patients, 13.8 ± 3.2 years) were assessed with magnetic resonance imaging, vascular ultrasound, applanation tonometry, and echocardiography from February 2015 until July 2017 and compared with 7 age- and sex-matched controls...
May 19, 2018: Journal of Clinical Rheumatology: Practical Reports on Rheumatic & Musculoskeletal Diseases
https://www.readbyqxmd.com/read/29782327/relation-of-white-matter-hyperintensities-and-motor-deficits-in-chronic-stroke
#13
Jarrod M Hicks, Edward Taub, Brent Womble, Ameen Barghi, Tyler Rickards, Victor W Mark, Gitendra Uswatte
BACKGROUND: Infarct size and location account for only a relatively small portion of post-stroke motor impairment, suggesting that other less obvious factors may be involved. OBJECTIVE: Examine the relationship between white matter hyperintensity (WMH) load among other factors and upper extremity motor deficit in patients with mild to moderate chronic stroke. METHODS: The magnetic resonance images of 28 patients were studied. WMH load was assessed as total WMH volume and WMH overlap with the corticospinal tract in the centrum semiovale...
2018: Restorative Neurology and Neuroscience
https://www.readbyqxmd.com/read/29782314/a-retrospective-belgian-multi-center-mri-biomarker-study-in-alzheimer-s-disease-remember
#14
Ellis Niemantsverdriet, Annemie Ribbens, Christine Bastin, Florence Benoit, Bruno Bergmans, Jean-Christophe Bier, Roxanne Bladt, Lene Claes, Peter Paul De Deyn, Olivier Deryck, Bernard Hanseeuw, Adrian Ivanoiu, Jean-Claude Lemper, Eric Mormont, Gaëtane Picard, Eric Salmon, Kurt Segers, Anne Sieben, Dirk Smeets, Hanne Struyfs, Evert Thiery, Jos Tournoy, Eric Triau, Anne-Marie Vanbinst, Jan Versijpt, Maria Bjerke, Sebastiaan Engelborghs
BACKGROUND: Magnetic resonance imaging (MRI) acquisition/processing techniques assess brain volumes to explore neurodegeneration in Alzheimer's disease (AD). OBJECTIVE: We examined the clinical utility of MSmetrix and investigated if automated MRI volumes could discriminate between groups covering the AD continuum and could be used as a predictor for clinical progression. METHODS: The Belgian Dementia Council initiated a retrospective, multi-center study and analyzed whole brain (WB), grey matter (GM), white matter (WM), cerebrospinal fluid (CSF), cortical GM (CGM) volumes, and WM hyperintensities (WMH) using MSmetrix in the AD continuum...
May 16, 2018: Journal of Alzheimer's Disease: JAD
https://www.readbyqxmd.com/read/29782307/cutaneous-manifestations-of-tuberous-sclerosis
#15
Mirjana Bakić, Marina Ratković, Branka Gledović, Balsa Vujović, Danilo Radunović, Vera Babić, Vladimir Prelević
Dear Editor, Tuberous sclerosis (TS) is an autosomal dominant multisystem disease, which occurs due to genetically determined hyperplasia of ectodermal and mesodermal cells. Clinical manifestations present on the skin and in the nervous system, kidneys, heart, and other organs. Recent studies estimate the incidence of TS at 1/6000 to 1/10,000 live births, and a prevalence in the general population of approximately 1 in 20,000 (1). There are two different genetic loci responsible for TS: 9q34 (TSC1-hamartin) and 16p13...
April 2018: Acta Dermatovenerologica Croatica: ADC
https://www.readbyqxmd.com/read/29782284/-magnetic-resonance-imaging-in-patients-with-implantable-devices-for-treatment-of-disturbed-heart-rhythm-review-of-the-current-situation
#16
A A Sviridova
The question of the possibility of MRI scanning in patients with cardiac implantable electronic devices (CIED) appeared simultaneously with the introduction of MRI in clinical practice. A lot of in-vitro, in-vivo and clinical researches were performed to estimate wat going on with CIED in strong magnetic field and is it possible to perform some unified protocol of safe MRI-scanning for these patients. Recommendations were provided, but not for the wide practice. MRI remained strongly contraindicated for CIED patient...
2018: Kardiologiia
https://www.readbyqxmd.com/read/29782242/case-254-posttraumatic-migrating-fat-embolus-causing-fat-emboli-syndrome
#17
Sébastien Molière, Stéphane Kremer, Guillaume Bierry
History An otherwise healthy 18-year-old man was admitted to the emergency department with a closed displaced fracture of the left femoral shaft ( Fig 1 ) after a high-velocity motorbike accident. At admission, other physical examination findings were unremarkable. Initial unenhanced and contrast material-enhanced (120 mL of Iomeron 400; Bracco Imaging, Milan, Italy) computed tomography (CT) was performed in the arterial and venous phases from the head to the knees. No abnormalities were noted in the brain or chest at initial CT...
June 2018: Radiology
https://www.readbyqxmd.com/read/29782071/evaluation-of-idiopathic-olfactory-loss-with-chemosensory-event-related-potentials-and-magnetic-resonance-imaging
#18
Jia Liu, Jayant M Pinto, Ling Yang, Linyin Yao, Xutao Miao, Yongxiang Wei
BACKGROUND: Idiopathic olfactory loss (IOL) accounts for a sizable fraction of olfactory dysfunction, but very little is known about its etiology and electrophysiological changes in the olfactory pathway. METHODS: We analyzed the physiology of IOL using chemosensory event-related potentials (ERPs) (olfactory and trigeminal: oERP and tERP) and olfactory pathway magnetic resonance imaging (MRI) measured in adult patients with IOL and healthy controls. Subjective olfactory function was measured by Toyota and Takagi (T&T) olfactometry and Sniffin' Sticks (SS)...
May 21, 2018: International Forum of Allergy & Rhinology
https://www.readbyqxmd.com/read/29782041/meta-analysis-of-brain-mechanisms-of-chewing-and-clenching-movements
#19
Chia-Shu Lin
BACKGROUND: Functional magnetic resonance imaging (fMRI) is widely used for investigating brain activation patterns associated with chewing and clenching movements. Whether studies consistently identify similar brain loci engaged in these movements remains unknown. OBJECTIVE: We investigated the consistency with which specific brain loci were reported to be activated during teeth-occluding movements, using the activation likelihood estimation (ALE) meta-analysis...
May 21, 2018: Journal of Oral Rehabilitation
https://www.readbyqxmd.com/read/29781852/the-effect-of-postmastectomy-radiation-therapy-on-breast-implants-material-analysis-on-silicone-and-polyurethane-prosthesis
#20
Federico Lo Torto, Michela Relucenti, Giuseppe Familiari, Nicola Vaia, Donato Casella, Roberto Matassa, Selenia Miglietta, Franco Marinozzi, Fabiano Bini, Ilaria Fratoddi, Fabio Sciubba, Raffaele Cassese, Vincenzo Tombolini, Diego Ribuffo
INTRODUCTION: The pathogenic mechanism underlying capsular contracture is still unknown. It is certainly a multifactorial process, resulting from human body reaction, biofilm activation, bacteremic seeding, or silicone exposure. The scope of the present article is to investigate the effect of hypofractionated radiotherapy protocol (2.66 Gy × 16 sessions) both on silicone and polyurethane breast implants. METHODS: Silicone implants and polyurethane underwent irradiation according to a hypofractionated radiotherapy protocol for the treatment of breast cancer...
May 17, 2018: Annals of Plastic Surgery
keyword
keyword
11026
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"