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https://www.readbyqxmd.com/read/29470640/quantitative-susceptibility-mapping-in-combination-with-water-fat-separation-for-simultaneous-liver-iron-and-fat-fraction-quantification
#1
Huimin Lin, Hongjiang Wei, Naying He, Caixia Fu, Shu Cheng, Jun Shen, Baisong Wang, Xu Yan, Chunlei Liu, Fuhua Yan
PURPOSES: To evaluate the feasibility of simultaneous quantification of liver iron concentration (LIC) and fat fraction (FF) using water-fat separation and quantitative susceptibility mapping (QSM). METHODS: Forty-five patients suspected of liver iron overload (LIO) were included. A volumetric interpolated breath-hold examination sequence for QSM and FF, a fat-saturated gradient echo sequence for R2 * , a spin echo sequence for LIC measurements and MRS analyses for FF (FF-MRS) were performed...
February 22, 2018: European Radiology
https://www.readbyqxmd.com/read/29469659/grading-of-oligodendroglial-tumors-of-the-brain-with-apparent-diffusion-coefficient-magnetic-resonance-spectroscopy-and-dynamic-susceptibility-contrast-imaging
#2
Muhammad Atif Naveed, Pradeep Goyal, Ajay Malhotra, Xiang Liu, Sonali Gupta, Manisha Mangla, Rajiv Mangla
Purpose We explored whether advanced magnetic resonance (MR) imaging techniques could grade oligodendrogliomas. Methods Forty patients (age 9-61 years) with oligodendroglial tumors were selected. There were 23 patients with World Health Organization grade II (group 1) and 17 patients with grade III (group 2) tumors. Apparent diffusion coefficient (ADC) maps were calculated by b values of 0 and 1000 s/mm2 . Dynamic susceptibility contrast (DSC) images were obtained during the first pass of a bolus of gadolinium-based contrast...
January 1, 2018: Neuroradiology Journal
https://www.readbyqxmd.com/read/29467681/glutamate-levels-and-resting-cerebral-blood-flow-in-anterior-cingulate-cortex-are-associated-at-rest-and-immediately-following-infusion-of-s-ketamine-in-healthy-volunteers
#3
Kirsten Borup Bojesen, Kasper Aagaard Andersen, Sophie Nordahl Rasmussen, Lone Baandrup, Line Malmer Madsen, Birte Yding Glenthøj, Egill Rostrup, Brian Villumsen Broberg
Progressive loss of brain tissue is seen in some patients with schizophrenia and might be caused by increased levels of glutamate and resting cerebral blood flow (rCBF) alterations. Animal studies suggest that the normalisation of glutamate levels decreases rCBF and prevents structural changes in hippocampus. However, the relationship between glutamate and rCBF in anterior cingulate cortex (ACC) of humans has not been studied in the absence of antipsychotics and illness chronicity. Ketamine is a noncompetitive N -methyl-D-aspartate receptor antagonist that transiently induces schizophrenia-like symptoms and neurobiological disturbances in healthy volunteers (HVs)...
2018: Frontiers in Psychiatry
https://www.readbyqxmd.com/read/29464462/gestational-and-lactational-exposure-to-dichlorinated-bisphenol-a-induces-early-alterations-of-hepatic-lipid-composition-in-mice
#4
Dounia El Hamrani, Amandine Chepied, William Même, Marc Mesnil, Norah Defamie, Sandra Même
OBJECTIVE: Using non-invasive magnetic resonance (MR) techniques and a histological approach, we assessed the outcomes of perinatal exposure at a low dose of 3,3'-DCBPA (2-chloro-4-[1-(3-chloro-4-hydroxyphenyl)-1-methylethyl]phenol) and/or 3,5-DCBPA (2,6-dichloro-4-[1-(4-hydroxyphenyl)-1-methylethyl]phenol) on mice livers. MATERIALS AND METHODS: Fertilized female Swiss mice were injected intraperitoneally during gestation and lactation with either vehicle control, 20 μg/kg/day of BPA, 3,5-DCBPA, 3,3'-DCBPA or a mixture (mix-DCBPA)...
February 20, 2018: Magma
https://www.readbyqxmd.com/read/29455454/oxidative-capacity-varies-along-the-length-of-healthy-human-tibialis-anterior
#5
Andreas Boss, Linda Heskamp, Vincent Breukels, Lauren J Bains, Mark J van Uden, Arend Heerschap
The rate of phosphocreatine (PCr) recovery (kPCr ) after exercise, characterizing muscle oxidative capacity, is traditionally assessed with unlocalized31 P magnetic resonance spectroscopy (MRS) using a single surface coil. However, because of intramuscular variation in fibre type and oxygen supply, kPCr may be non-uniform within muscles. We tested this along the length of the tibialis anterior (TA) muscle in 10 male volunteers. For this purpose we employed a 3T MR system with a31 P/1 H volume transmit coil combined with a home-built31 P phased-array receive probe, consisting of 5 coil elements covering the TA muscle length...
February 18, 2018: Journal of Physiology
https://www.readbyqxmd.com/read/29454110/study-of-lipid-metabolism-by-estimating-the-fat-fraction-in-different-breast-tissues-and-in-various-breast-tumor-sub-types-by-in-vivo-1-h-mr-spectroscopy
#6
Khushbu Agarwal, Uma Sharma, Sandeep Mathur, Vurthaluru Seenu, Rajinder Parshad, Naranamangalam R Jagannathan
PURPOSE: To evaluate the utility of fat fraction (FF) for the differentiation of different breast tissues and in various breast tumor subtypes using in vivo proton ( 1 H) magnetic resonance spectroscopy (MRS). METHODS: 1 H MRS was performed on 68 malignant, 35 benign, and 30 healthy volunteers at 1.5 T. Malignant breast tissues of patients were characterized into different subtypes based on the differences in the expression of hormone receptors and the FF was calculated...
February 14, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29449278/7t-brain-mrs-in-hiv-infection-correlation-with-cognitive-impairment-and-performance-on-neuropsychological-tests
#7
M Mohamed, P B Barker, R L Skolasky, N Sacktor
BACKGROUND AND PURPOSE: Validated neuroimaging markers of HIV-associated neurocognitive disorder in patients on antiretroviral therapy are urgently needed for clinical trials. The purpose of this study was to explore the relationship between cognitive impairment and brain metabolism in older subjects with HIV infection. It was hypothesized that MR spectroscopy measurements related to neuronal health and function (particularly N -acetylaspartate and glutamate) would be lower in HIV-positive subjects with worse cognitive performance...
February 15, 2018: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/29446149/distinction-of-the-gaba-2-29-ppm-resonance-using-triple-refocusing-at-3-t-in-vivo
#8
Vivek Tiwari, Zhongxu An, Yiming Wang, Changho Choi
PURPOSE: To develop 1 H MR spectroscopy that provides distinction of γ-aminobutyric acid (GABA) signal at 3 T in vivo. METHODS: Triple-refocusing was tailored at 3 T, with numerical simulations and phantom validation, for distinction of the GABA 2.29-ppm resonance from the neighboring glutamate resonance. The optimization was performed on the inter-RF pulse time delays and the duration and carrier frequency of a non-slice-selective RF pulse. The optimized triple refocusing was tested in multiple regions in 6 healthy subjects, including hippocampus...
February 14, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29446118/water-suppression-in-the-human-brain-with-hypergeometric-rf-pulses-for-single-voxel-and-multi-voxel-mr-spectroscopy
#9
Kimberly L Chan, Ronald Ouwerkerk, Peter B Barker
PURPOSE: To develop and investigate a novel water suppression sequence with hypergeometric pulses at 3 T. METHODS: Simulations were used to optimize the delays and amplitudes of 5 hypergeometric prepulses, to minimize the residual water over a range of T 1 and B 1 values. Single-voxel data with hypergeometric water suppression (HGWS) prepulses were acquired in the centrum semiovale, 2 parietal regions, and insula of 7 subjects, and compared with VAPOR water suppression...
February 14, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29436038/comparison-of-reproducibility-of-single-voxel-spectroscopy-and-whole-brain-magnetic-resonance-spectroscopy-imaging-at-3t
#10
Yue Zhang, Edward Taub, Nouha Salibi, Gitendra Uswatte, Andrew A Maudsley, Sulaiman Sheriff, Brent Womble, Victor W Mark, David C Knight
To date, single voxel spectroscopy (SVS) is the most commonly used MRS technique. SVS is relatively easy to use and provides automated and immediate access to the resulting spectra. However, it is also limited in spatial coverage. A new and very promising MRS technique allows for whole-brain MR spectroscopic imaging (WB-MRSI) with much improved spatial resolution. Establishing the reproducibility of data obtained using SVS and WB-MRSI is an important first step for using these techniques to evaluate longitudinal changes in metabolite concentration...
February 13, 2018: NMR in Biomedicine
https://www.readbyqxmd.com/read/29427835/phenytoin-related-ataxia-in-patients-with-epilepsy-clinical-and-radiological-characteristics
#11
Priya D Shanmugarajah, Nigel Hoggard, Daniel P Aeschlimann, Pascale C Aeschlimann, Gary J Dennis, Stephen J Howell, Markus Reuber, Richard A Grünewald, Marios Hadjivassiliou
PURPOSE: Phenytoin is an effective anticonvulsant for focal epilepsy. Its use can be associated with long-term adverse effects including cerebellar ataxia. Whilst phenytoin is toxic to Purkinje cells in vitro; the clinical and radiological phenotype and mechanism of cerebellar degeneration in vivo remain unclear. We describe the prevalence, clinical and radiological characteristics of phenytoin-related ataxia. METHODS: Patients with epilepsy receiving treatment with phenytoin were recruited from the Epilepsy clinics at Royal Hallamshire Hospital, Sheffield, UK...
February 2, 2018: Seizure: the Journal of the British Epilepsy Association
https://www.readbyqxmd.com/read/29426954/3d-7li-magnetic-resonance-imaging-of-brain-lithium-distribution-in-bipolar-disorder
#12
Fiona Elizabeth Smith, Peter Edward Thelwall, Joe Necus, Carly Jay Flowers, Andrew Matthew Blamire, David Andrew Cousins
Lithium is a major treatment for bipolar disorder and the likelihood of a favourable response may be determined by its distribution in the brain. Lithium can be directly detected by magnetic resonance (MR), but previous 7Li MR spectroscopy studies have demonstrated that this is challenging compared to conventional 1H MR imaging due to the MR properties of the lithium nucleus and its low concentration in brain tissue, as dictated by therapeutic dose. We have tested and implemented a highly efficient balanced steady-state free precession 7Li-MRI method to address these challenges and enable MRI of brain lithium in a short duration scan...
February 9, 2018: Molecular Psychiatry
https://www.readbyqxmd.com/read/29417380/assessing-long-term-neuroinflammatory-responses-to-encephalopathy-using-mri-approaches-in-a-rat-endotoxemia-model
#13
Rheal A Towner, D Saunders, N Smith, W Towler, M Cruz, S Do, J E Maher, K Whitaker, M Lerner, K A Morton
Sepsis-associated encephalopathy (SAE) induces neuroinflammation, which is associated with cognitive impairment (CI). CI is also correlated with aging. We used contrast-enhanced magnetic resonance imaging (MRI), perfusion MRI, and MR spectroscopy to assess long-term alterations in BBB permeability, microvascularity, and metabolism, respectively, in a rat lipopolysaccharide-induced SAE model. Free radical-targeted molecular MRI was used to detect brain radical levels at 24 h and 1 week post-LPS injection. CE-MRI showed increased Gd-DTPA uptake in LPS rat brains at 24 h in cerebral cortex, hippocampus, thalamus, and perirhinal cortex regions...
February 7, 2018: GeroScience
https://www.readbyqxmd.com/read/29411415/probing-cardiac-metabolism-by-hyperpolarized-13c-mr-using-an-exclusively-endogenous-substrate-mixture-and-photo-induced-nonpersistent-radicals
#14
Jessica A M Bastiaansen, Hikari A I Yoshihara, Andrea Capozzi, Juerg Schwitter, Rolf Gruetter, Matthew E Merritt, Arnaud Comment
PURPOSE: To probe the cardiac metabolism of carbohydrates and short chain fatty acids simultaneously in vivo following the injection of a hyperpolarized 13 C-labeled substrate mixture prepared using photo-induced nonpersistent radicals. METHODS: Droplets of mixed [1-13 C]pyruvic and [1-13 C]butyric acids were frozen into glassy beads in liquid nitrogen. Ethanol addition was investigated as a means to increase the polarization level. The beads were irradiated with ultraviolet light and the radical concentration was measured by ESR spectroscopy...
February 6, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29408682/neurochemical-changes-in-unilateral-cerebralhemisphere-during-the-subacute-stage-of-focal-cerebral-ischemia-reperfusion-in-rats-an-ex-vivo-1h-magnetic-resonance-spectroscopy-study
#15
Qun Huang, Chen Li, Nengzhi Xia, Liangcai Zhao, Dan Wang, Yunjun Yang, Hongchang Gao
Understanding the subacute may shed light on the mechanism of cerebral ischemia. The present study aimed to explore metabolic features underlying subacute stage of ischemia-reperfusion injury and developing effective treatments. Rats were divided into three groups: the permanent middle cerebral artery occlusion (pMCAO), transient cerebral focal ischemia (tMCAO) and sham group. Evaluation of animal models was performed by the neurological deficit, MR images and pathological morphological abnormality. To elucidate metabolic changes, we conducted a comparative analysis of metabolic composition of unilateral brain tissue using 1H nuclear magnetic resonance spectroscopy...
January 31, 2018: Brain Research
https://www.readbyqxmd.com/read/29404634/neural-changes-associated-with-cerebellar-tdcs-studied-using-mr-spectroscopy
#16
Roya Jalali, Alimul Chowdhury, Martin Wilson, R Chris Miall, Joseph M Galea
Anodal cerebellar transcranial direct current stimulation (tDCS) is known to enhance motor learning, and therefore, has been suggested to hold promise as a therapeutic intervention. However, the neural mechanisms underpinning the effects of cerebellar tDCS are currently unknown. We investigated the neural changes associated with cerebellar tDCS using magnetic resonance spectroscopy (MRS). 34 healthy participants were divided into two groups which received either concurrent anodal or sham cerebellar tDCS during a visuomotor adaptation task...
February 5, 2018: Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation Cérébrale
https://www.readbyqxmd.com/read/29403347/brain-metabolite-diffusion-from-ultra-short-to-ultra-long-time-scales-what-do-we-learn-where-should-we-go
#17
Julien Valette, Clémence Ligneul, Charlotte Marchadour, Chloé Najac, Marco Palombo
In vivo diffusion-weighted MR spectroscopy (DW-MRS) allows measuring diffusion properties of brain metabolites. Unlike water, most metabolites are confined within cells. Hence, their diffusion is expected to purely reflect intracellular properties, opening unique possibilities to use metabolites as specific probes to explore cellular organization and structure. However, interpretation and modeling of DW-MRS, and more generally of intracellular diffusion, remains difficult. In this perspective paper, we will focus on the study of the time-dependency of brain metabolite apparent diffusion coefficient (ADC)...
2018: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/29401483/alcohol-consumption-but-not-smoking-is-associated-with-higher-mr-derived-liver-fat-in-an-asymptomatic-study-population
#18
Christian Bayerl, Roberto Lorbeer, Margit Heier, Christa Meisinger, Susanne Rospleszcz, Anina Schafnitzel, Hannah Patscheider, Sigrid Auweter, Annette Peters, Birgit Ertl-Wagner, Maximilian Reiser, Fabian Bamberg, Holger Hetterich
BACKGROUND: The aim of our study was to determine the relation of alcohol consumption and cigarette smoking on continuous-measured hepatic fat fraction (HFF) in a population free of cardiovascular disease. We suggested a direct correlation of alcohol consumption with HFF and increased HFF in former smokers compared to current smokers. METHODS: Data from 384 subjects (mean age: 56 years, 58% men) of a population-based cohort study (KORA) were included in a cross-sectional design...
2018: PloS One
https://www.readbyqxmd.com/read/29396939/creatine-transporter-deficiency-in-two-brothers-with-autism-spectrum-disorder
#19
Halil Ibrahim Aydin
BACKGROUND: Creatine transporter deficiency (CTD) is a treatable, X-linked, inborn error of metabolism. CASE CHARACTERISTICS: Two brothers with autism spectrum disorder were diagnosed with CTD at the ages of 17 and 12 years. Both were found to have a previously reported hemizygous p.408delF (c.1216_1218delTTC) deletion mutation. OUTCOME: Both patients were given creatine monohydrate, L-arginine, L-glycine and S-adenosylmethionine, which partially improved the behavioral problems...
January 15, 2018: Indian Pediatrics
https://www.readbyqxmd.com/read/29388313/deep-learning-approaches-for-detection-and-removal-of-ghosting-artifacts-in-mr-spectroscopy
#20
Sreenath P Kyathanahally, André Döring, Roland Kreis
PURPOSE: To make use of deep learning (DL) methods to detect and remove ghosting artifacts in clinical magnetic resonance spectra of human brain. METHODS: Deep learning algorithms, including fully connected neural networks, deep-convolutional neural networks, and stacked what-where auto encoders, were implemented to detect and correct MR spectra containing spurious echo ghost signals. The DL methods were trained on a huge database of simulated spectra with and without ghosting artifacts that represent complex variations of ghost-ridden spectra, transformed to time-frequency spectrograms...
February 1, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
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