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https://www.readbyqxmd.com/read/28445310/diagnostic-accuracy-of-serum-alanine-aminotransferase-as-biomarker-for-nonalcoholic-fatty-liver-disease-and-insulin-resistance-in-healthy-subjects-using-3t-mr-spectroscopy
#1
Jose Luis Martin-Rodriguez, Jorge Gonzalez-Cantero, Alvaro Gonzalez-Cantero, Juan Pedro Arrebola, Jorge Luis Gonzalez-Calvin
Recognition of the close relationship of nonalcoholic fatty liver disease (NAFLD) with diabetes mellitus 2, obesity, metabolic syndrome, and cardiovascular disease has stimulated growing interest in NAFLD as a public health problem. Serum alanine aminotransferase (ALT) has been proposed as a marker of NAFLD, but levels are within the range currently considered "normal" in a large proportion of NAFLD subjects.The aim of the study was to determine the diagnostic accuracy of serum ALT for identifying individuals with NAFLD, using 3-Tesla (T) magnetic resonance spectroscopy (H-MRS)...
April 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28444923/anaerobic-respiration-on-self-doped-conjugated-polyelectrolytes-impact-of-chemical-structure
#2
Nathan D Kirchhofer, Samantha R McCuskey, Cheng-Kang Mai, Guillermo C Bazan
We probe anaerobic respiration of bacteria in the presence of conjugated polyelectrolytes (CPEs). Three different CPEs were used to probe how structural variations impact biocurrent generation from Shewanella oneidensis MR-1. For the self-doped anionic CPE only, absorption spectroscopy shows that the addition of S. oneidensis MR-1 leads to the disappearance of the polaron (radical cation) band at >900 nm and an increase in the band at 735 nm due to the neutral species, consistent with electron transfer from microbe to polymer...
April 26, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28432796/an-acetone-based-phantom-for-quantitative-diffusion-mri
#3
Xiaoke Wang, Scott B Reeder, Diego Hernando
PURPOSE: To propose and evaluate an acetone-D2 O phantom that has an extended range of apparent diffusion coefficient (ADC) for quantitative diffusion magnetic resonance imaging (MRI), as well as to compare its properties to previously described water-based phantoms. MATERIALS AND METHODS: The proposed acetone-D2 O, and previously described sucrose water solution and polyvinylpyrrolidone (PVP) water solution phantoms, were constructed in a number of concentrations between 0% and 50%...
April 22, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28432403/bone-marrow-fat-content-in-70-adolescent-girls-with-anorexia-nervosa-magnetic-resonance-imaging-and-magnetic-resonance-spectroscopy-assessment
#4
Kirsten Ecklund, Sridhar Vajapeyam, Robert V Mulkern, Henry A Feldman, Jennifer M O'Donnell, Amy D DiVasta, Catherine M Gordon
BACKGROUND: Adolescents and women with anorexia nervosa have increased bone marrow fat and decreased bone formation, at least in part due to hormonal changes leading to preferential stem cell differentiation to adipocytes over osteoblasts. OBJECTIVE: The purpose of this study was to evaluate marrow fat content and correlate with age and disease severity using knee MRI with T1 relaxometry (T1-R) and MR spectroscopy (MRS) in 70 adolescents with anorexia nervosa. MATERIALS AND METHODS: We enrolled 70 girls with anorexia nervosa who underwent 3-T knee MRI with coronal T1-W images, T1-R and single-voxel proton MRS at 30 and 60 ms TE...
April 22, 2017: Pediatric Radiology
https://www.readbyqxmd.com/read/28431025/1h-magnetic-resonance-spectroscopy-of-live-human-sperm
#5
S Reynolds, S J Calvert, M N Paley, A A Pacey
STUDY QUESTION: Can 1H Magnetic Resonance Spectroscopy (MRS) be used to obtain information about the molecules and metabolites in live human spermatozoa? SUMMARY ANSWER: Percoll-based density gradient centrifugation (DGC) followed by a further two washing steps, yielded enough sperm with minimal contamination (<0.01%) from seminal fluid to permit effective MRS which detected significant differences (p < 0.05) in the choline/glycerophosphocholine, lipid and lactate regions of the 1H MRS spectrum between sperm in the pellet and those from the 40/80% interface...
April 18, 2017: Molecular Human Reproduction
https://www.readbyqxmd.com/read/28428210/proton-chemical-shift-imaging-study-of-the-combined-antiretroviral-therapy-impact-on-neurometabolic-parameters-in-chronic-hiv-infection
#6
J Boban, D Kozic, V Turkulov, D Lendak, M Bjelan, M Semnic, S Brkic
BACKGROUND AND PURPOSE: The introduction of combination antiretroviral therapy has failed to reduce the high prevalence of mild forms of HIV-associated neurocognitive disorders. The aim of this study was to test the effect of combined antiretroviral therapy on brain metabolite ratios in chronic HIV infection by using proton chemical shift imaging. MATERIALS AND METHODS: We performed 2D chemical shift imaging in 91 subjects (31 HIV+ patients with chronic infection on combination antiretroviral therapy, 19 combination antiretroviral therapy-na|fkve HIV+ subjects with chronic infection, and 41 healthy controls), covering frontal and parietal subcortical white and cingulate gyrus gray matter, analyzing ratios of NAA/Cr and Cho/Cr on long-TE and mIns/Cr on short-TE MR spectroscopy...
April 20, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28425537/using-fluorescently-labeled-magnetic-nanocomposites-as-a-dual-contrast-agent-for-optical-and-magnetic-resonance-imaging
#7
Taofeng Zhu, Xiuqin Ma, Ruhua Chen, Zhijun Ge, Jun Xu, Xiaoke Shen, Lei Jia, Tao Zhou, Yifeng Luo, Tieliang Ma
Dual-modality imaging probes synergistically combine magnetic resonance (MR) and fluorescence into a single nanocomposite. This promising technique affords a new level of flexibility for molecular imaging uses in biomedical research. In this study, we report a new strategy for the synthesis of a novel attapulgite nanorod-based atta@Fe3O4@[Ru(bpy)2(fmp)]Cl2 nanocomposite (atta@Fe3O4@Ru NC). Our synthesized NC has both photoluminescent and magnetic properties, bright fluorescence, as well as significant magnetic resonance...
April 20, 2017: Biomaterials Science
https://www.readbyqxmd.com/read/28419582/free-breathing-liver-fat-quantification-using-a-multiecho-3d-stack-of-radial-technique
#8
Tess Armstrong, Isabel Dregely, Alto Stemmer, Fei Han, Yutaka Natsuaki, Kyunghyun Sung, Holden H Wu
PURPOSE: The diagnostic gold standard for nonalcoholic fatty liver disease is an invasive biopsy. Noninvasive Cartesian MRI fat quantification remains limited to a breath-hold (BH). In this work, a novel free-breathing 3D stack-of-radial (FB radial) liver fat quantification technique is developed and evaluated in a preliminary study. METHODS: Phantoms and healthy subjects (n = 11) were imaged at 3 Tesla. The proton-density fat fraction (PDFF) determined using FB radial (with and without scan acceleration) was compared to BH single-voxel MR spectroscopy (SVS) and BH 3D Cartesian MRI using linear regression (correlation coefficient ρ and concordance coefficient ρc ) and Bland-Altman analysis...
April 16, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28415069/comparison-of-bioimpedance-and-underwater-weighing-body-fat-percentage-before-and-acutely-after-exercise-at-varying-intensities
#9
Brett S Nickerson, Michael R Esco, Brian M Kliszczewicz, Todd J Freeborn
Nickerson, BS, Esco, MR, Kliszczewicz, BM, and Freeborn, TJ. Comparison of bioimpedance and underwater weighing body fat percentage before and acutely after exercise at varying intensities. J Strength Cond Res 31(5): 1395-1402, 2017-The purpose of this study was to compare single-frequency bioelectrical impedance analysis (BIA) and bioimpedance spectroscopy (BIS) with underwater weighing (UWW) body fat percentage (BF%) before (PRE), immediately post (IP), and 60 minutes post (60P) an acute bout of moderate and vigorous aerobic exercise...
May 2017: Journal of Strength and Conditioning Research
https://www.readbyqxmd.com/read/28414427/enhancing-extracellular-electron-transfer-of-shewanella-oneidensis-mr-1-through-coupling-improved-flavin-synthesis-and-metal-reducing-conduit-for-pollutant-degradation
#10
Di Min, Lei Cheng, Feng Zhang, Xue-Na Huang, Dao-Bo Li, Dong-Feng Liu, Tai-Chu Lau, Yang Mu, Han-Qing Yu
Dissimilatory metal reducing bacteria (DMRB) are capable of extracellular electron transfer (EET) to insoluble metal oxides, which are used as external electron acceptors by DMRB for their anaerobic respiration. The EET process has important contribution to environmental remediation mineral cycling, and bioelectrochemical systems. However, the low EET efficiency remains to be one of the major bottlenecks for its practical applications for pollutant degradation. In this work, Shewanella oneidensis MR-1, a model DMRB, was used to examine the feasibility of enhancing the EET and its biodegradation capacity through genetic engineering...
April 21, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28409252/pediatric-brain-mri-part-2-advanced-techniques
#11
REVIEW
Mai-Lan Ho, Norbert G Campeau, Thang D Ngo, Unni K Udayasankar, Kirk M Welker
Pediatric neuroimaging is a complex and specialized field that uses magnetic resonance (MR) imaging as the workhorse for diagnosis. MR protocols should be tailored to the specific indication and reviewed by the supervising radiologist in real time. Targeted advanced imaging sequences can be added to provide information regarding tissue microstructure, perfusion, metabolism and function. In part 2 of this review, we highlight the utility of advanced imaging techniques for superior evaluation of pediatric neurologic disease...
May 2017: Pediatric Radiology
https://www.readbyqxmd.com/read/28409152/the-association-between-imaging-parameters-of-the-paraspinal-muscles-spinal-degeneration-and-low-back-pain
#12
REVIEW
Leonid Kalichman, Eli Carmeli, Ella Been
This narrative review investigated imaging parameters of the paraspinal muscles and their association with spinal degenerative features and low back pain (LBP) found in the literature. Three principal signs of muscle degeneration were detected on imaging: decreased muscle size, decreased radiographic density, and increased fat deposits. Men have a higher density of paraspinal muscles than women, younger individuals have a higher density than older ones, and lean individuals have a higher density than those with an increased body mass index...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28408961/the-usefulness-of-diagnostic-imaging-for-the-assessment-of-pain-symptoms-in-temporomandibular-disorders
#13
REVIEW
Shigeaki Suenaga, Kunihiro Nagayama, Taisuke Nagasawa, Hiroko Indo, Hideyuki J Majima
The causes of pain symptoms in the temporomandibular joint (TMJ) and masticatory muscle (MM) regions may not be determined by clinical examination alone. In this review, we document that pain symptoms of the TMJ and MM regions in patients with temporomandibular disorders (TMDs) are associated with computed tomography and magnetic resonance (MR) findings of internal derangement, joint effusion, osteoarthritis, and bone marrow edema. However, it is emphasized that these imaging findings must not be regarded as the unique and dominant factors in defining TMJ pain...
November 2016: Japanese Dental Science Review
https://www.readbyqxmd.com/read/28396271/physicochemical-characterization-of-water-soluble-chitosan-derivatives-with-singlet-oxygen-quenching-and-antibacterial-capabilities
#14
Noelia L Vanden Braber, Ladislao I Díaz Vergara, Faustino E Morán Vieyra, Claudio D Borsarelli, Mariana M Yossen, Jorge R Vega, Silvia G Correa, Mariana A Montenegro
New water-soluble chitosan derivatives (WSCh) were obtained by Maillard reaction (MR) between glucosamine (GA) with both low and medium molecular weight chitosans (Ch). The WSCh showed larger solubility than the respective Ch, while their deacetylation degree (DD) decreased by approximately 12%. Infrared spectroscopy experiments of WSCh confirmed the formation of imine bonds after MR with intensified pyranose structure, and sugar molecules as polymer branches. However, a 6-times reduction of the molecular weight of WSCh was measured, indicating the breakdown of the polysaccharide chain during the MR...
April 8, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28395788/diagnosis-and-treatment-of-chronic-mesenteric-ischemia-an-update
#15
REVIEW
Jeroen J Kolkman, Robert H Geelkerken
Although the prevalence of mesenteric artery stenoses (MAS) is high, symptomatic chronic mesenteric ischemia (CMI) is rare. The collateral network in the mesenteric circulation, a remnant of the extensive embryonal vascular network, serves to prevent most cases of ischemia. This explains the high incidence of MAS and relative rarity of cases of CMI. The number of affected vessels is the major determinant in CMI development. Most subjects with single vessel mesenteric stenosis do not develop ischemic complaints...
February 2017: Best Practice & Research. Clinical Gastroenterology
https://www.readbyqxmd.com/read/28391791/molecular-and-metabolic-imaging-in-multiple-sclerosis
#16
REVIEW
Marcello Moccia, Olga Ciccarelli
Multiple sclerosis is a multifactorial disease with heterogeneous pathogenetic mechanisms, which deserve to be studied to evaluate new possible targets for treatments and improve patient management. MR spectroscopy and PET allow assessing in vivo the molecular and metabolic mechanisms underlying the pathogenesis of multiple sclerosis. This article focuses on the relationship between these imaging techniques and the biologic and chemical pathways leading to multiple sclerosis pathology and its clinical features...
May 2017: Neuroimaging Clinics of North America
https://www.readbyqxmd.com/read/28388602/maturational-decrease-of-glutamate-in-the-human-cerebral-cortex-from-childhood-to-young-adulthood-a-1-h-mr-spectroscopy-study
#17
Mami Shimizu, Yuji Suzuki, Kenichi Yamada, Satoshi Ueki, Masaki Watanabe, Hironaka Igarashi, Tsutomu Nakada
BACKGROUND: The aim of the present study was to investigate maturational changes in glutamate (Glu) in the human cerebral cortex from childhood to young adulthood using 3.0-Tesla proton magnetic resonance spectroscopy ((1)H-MRS), which is capable of quantifying Glu in vivo. METHODS: Normal volunteers comprising 11 children (aged 4-13 years) and 11 young adults (aged 18-33 years) participated in the study. Single-voxel point-resolved spectroscopy (PRESS, repetition time/echo time=2000/80 ms) was performed in the frontal and occipital cortices, and the Glu to creatine ratio (Glu/Cr) and N-acetylaspartate to creatine ratio (NAA/Cr) were determined...
April 7, 2017: Pediatric Research
https://www.readbyqxmd.com/read/28386718/globus-pallidus-mr-signal-abnormalities-in-children-with-chronic-liver-disease-and-or-porto-systemic-shunting
#18
Sylviane Hanquinet, Claire Morice, Delphine S Courvoisier, Vladimir Cousin, Mehrak Anooshiravani, Laura Merlini, Valérie A McLin
OBJECTIVES: Detection of subclinical hepatic encephalopathy in children is difficult. We aimed to assess the changes in imaging of the central nervous system in children with chronic liver disease using MR imaging, diffusion, and (1)H -spectroscopy. METHODS: Forty three children with chronic liver disease and/or porto-systemic shunting (111.4±56.9 months) and 24 controls (72.0±51.8 months) underwent brain MRI/spectroscopy on a 1.5T to examine T1, T2, ADC, Cho/Cr, ml/Cr, Glx/Cr ratio spectroscopy in the globus pallidus...
April 6, 2017: European Radiology
https://www.readbyqxmd.com/read/28385884/classification-of-high-grade-glioma-into-tumor-and-nontumor-components-using-support-vector-machine
#19
D T Blumenthal, M Artzi, G Liberman, F Bokstein, O Aizenstein, D Ben Bashat
BACKGROUND AND PURPOSE: Current imaging assessment of high-grade brain tumors relies on the Response Assessment in Neuro-Oncology criteria, which measure gross volume of enhancing and nonenhancing lesions from conventional MRI sequences. These assessments may fail to reliably distinguish tumor and nontumor. This study aimed to classify enhancing and nonenhancing lesion areas into tumor-versus-nontumor components. MATERIALS AND METHODS: A total of 140 MRI scans obtained from 32 patients with high-grade gliomas and 6 patients with brain metastases were included...
April 6, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28382555/fitting-interrelated-datasets-metabolite-diffusion-and-general-lineshapes
#20
Victor Adalid, André Döring, Sreenath Pruthviraj Kyathanahally, Christine Sandra Bolliger, Chris Boesch, Roland Kreis
OBJECTIVE: Simultaneous modeling of true 2-D spectroscopy data, or more generally, interrelated spectral datasets has been described previously and is useful for quantitative magnetic resonance spectroscopy applications. In this study, a combined method of reference-lineshape enhanced model fitting and two-dimensional prior-knowledge fitting for the case of diffusion weighted MR spectroscopy is presented. MATERIALS AND METHODS: Time-dependent field distortions determined from a water reference are applied to the spectral bases used in linear-combination modeling of interrelated spectra...
April 5, 2017: Magma
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