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MR fingerprint

Huiqiong Xie, Miao Huang, Qiping Hu, Kejian Sun, Huayu Wu, Wei Shu, Xiaolong Li, Ling Fang
In previous work, a snake venom arginine esterase (SVAE), agkihpin from the venom of Gloydius halys Pallas, was isolated and its biochemical data including Mr, PI, amino acid components and sugar content was collected. Here, the agkihpin was cloned and further characterized and we found that agkihpin could promote ADP-induced platelets aggregation, hydrolyze fibrin, cleave Aα and Bβ chains of fibrinogen and reduce the thrombosis induced by thrombin. Moreover, agkihpin hydrolyzed TAME with optimum temperatures at 30 °C-45 °C, and the hydrolysis was inhibited by EDTA, PMSF, DTT and promoted by Ca(2+), Fe(3+), Mg(2+), Zn(2+)...
September 22, 2016: Toxicon: Official Journal of the International Society on Toxinology
Rossella Canese, Delia Mezzanzanica, Marina Bagnoli, Stefano Indraccolo, Silvana Canevari, Franca Podo, Egidio Iorio
Epithelial ovarian cancer (EOC) is the gynecological malignancy with the highest death rate, characterized by frequent relapse and onset of drug resistance. Disease diagnosis and therapeutic follow-up could benefit from application of molecular imaging approaches, such as magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), able to monitor metabolic and functional alterations and investigate the underlying molecular mechanisms. Here, we overview the quantitative alterations that occur during either orthotopic or subcutaneous growth of preclinical EOC models...
2016: Frontiers in Oncology
Jakob Assländer, Steffen J Glaser, Jürgen Hennig
PURPOSE: This article discusses the signal behavior in the case the flip angle in steady-state free precession sequences is continuously varied as suggested for MR-fingerprinting sequences. Flip angle variations prevent the establishment of a steady state and introduce instabilities regarding to magnetic field inhomogeneities and intravoxel dephasing. We show how a pseudo steady state can be achieved, which restores the spin echo nature of steady-state free precession. METHODS: Based on geometrical considerations, relationships between the flip angle, repetition and echo time are derived that suffice to the establishment of a pseudo steady state...
April 15, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Fani Deligianni, David W Carmichael, Gary H Zhang, Chris A Clark, Jonathan D Clayden
In Diffusion Weighted MR Imaging (DWI), the signal is affected by the biophysical properties of neuronal cells and their relative placement, as well as extra-cellular tissue compartments. Typically, microstructural indices, such as fractional anisotropy (FA) and mean diffusivity (MD), are based on a tensor model that cannot disentangle the influence of these parameters. Recently, Neurite Orientation Dispersion and Density Imaging (NODDI) has exploited multi-shell acquisition protocols to model the diffusion signal as the contribution of three tissue compartments...
2016: PloS One
Bob L Hou, Sanjay Bhatia, Jeffrey S Carpenter
For pre-surgical planning we present quantitative comparison of the location of the hand motor functional area determined by right hand finger tapping BOLD fMRI, resting state BOLD fMRI, and anatomically using high resolution T1 weighted images. Data were obtained on 10 healthy subjects and 25 patients with left sided brain tumors. Our results show that there are important differences in the locations (i.e., > 20 mm) of the determined hand motor voxels by these three MR imaging methods. This can have significant effect on the pre-surgical planning of these patients depending on the modality used...
2016: NeuroImage: Clinical
Jesse I Hamilton, Yun Jiang, Yong Chen, Dan Ma, Wei-Ching Lo, Mark Griswold, Nicole Seiberlich
PURPOSE: To introduce a two-dimensional MR fingerprinting (MRF) technique for quantification of T1 , T2 , and M0 in myocardium. METHODS: An electrocardiograph-triggered MRF method is introduced for mapping myocardial T1 , T2 , and M0 during a single breath-hold in as short as four heartbeats. The pulse sequence uses variable flip angles, repetition times, inversion recovery times, and T2 preparation dephasing times. A dictionary of possible signal evolutions is simulated for each scan that incorporates the subject's unique variations in heart rate...
April 1, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Yun Jiang, Dan Ma, Renate Jerecic, Jeffrey Duerk, Nicole Seiberlich, Vikas Gulani, Mark A Griswold
PURPOSE: The purpose of the study is to develop a quantitative method for the relaxation properties with a reduced radio frequency (RF) power deposition by combining magnetic resonance fingerprinting (MRF) technique with quick echo splitting NMR imaging technique (QUEST). METHODS: A QUEST-based MRF sequence was implemented to acquire high-order echoes by increasing the gaps between RF pulses. Bloch simulations were used to calculate a dictionary containing the range of physically plausible signal evolutions using a range of T1 and T2 values based on the pulse sequence...
February 28, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Bo Zhao, Kawin Setsompop, Huihui Ye, Stephen F Cauley, Lawrence L Wald
This paper introduces a statistical estimation framework for magnetic resonance (MR) fingerprinting, a recently proposed quantitative imaging paradigm. Within this framework, we present a maximum likelihood (ML) formalism to estimate multiple MR tissue parameter maps directly from highly undersampled, noisy k-space data. A novel algorithm, based on variable splitting, the alternating direction method of multipliers, and the variable projection method, is developed to solve the resulting optimization problem...
August 2016: IEEE Transactions on Medical Imaging
Chaitra Badve, Alice Yu, Matthew Rogers, Dan Ma, Yiying Liu, Mark Schluchter, Jeffrey Sunshine, Mark Griswold, Vikas Gulani
Magnetic resonance fingerprinting (MRF) is a method of image acquisition that produces multiple MR parametric maps from a single scan. Here, we describe the normal range and progression of MRF-derived relaxometry values with age in healthy individuals. 56 normal volunteers (ages 11-71 years, M:F 24:32) were scanned. Regions of interest were drawn on T1 and T2 maps in 38 areas, including lobar and deep white matter, deep gray nuclei, thalami and posterior fossa structures. Relaxometry differences were assessed using a forward stepwise selection of a baseline model including either gender, age, or both, where variables were included if they contributed significantly (p<0...
December 2015: Tomography: a Journal for Imaging Research
Yong Chen, Yun Jiang, Shivani Pahwa, Dan Ma, Lan Lu, Michael D Twieg, Katherine L Wright, Nicole Seiberlich, Mark A Griswold, Vikas Gulani
PURPOSE: To develop a magnetic resonance (MR) "fingerprinting" technique for quantitative abdominal imaging. MATERIALS AND METHODS: This HIPAA-compliant study had institutional review board approval, and informed consent was obtained from all subjects. To achieve accurate quantification in the presence of marked B0 and B1 field inhomogeneities, the MR fingerprinting framework was extended by using a two-dimensional fast imaging with steady-state free precession, or FISP, acquisition and a Bloch-Siegert B1 mapping method...
April 2016: Radiology
Yun Jiang, Dan Ma, Nicole Seiberlich, Vikas Gulani, Mark A Griswold
PURPOSE: This study explores the possibility of using gradient echo-based sequences other than balanced steady-state free precession (bSSFP) in the magnetic resonance fingerprinting (MRF) framework to quantify the relaxation parameters . METHODS: An MRF method based on a fast imaging with steady-state precession (FISP) sequence structure is presented. A dictionary containing possible signal evolutions with physiological range of T1 and T2 was created using the extended phase graph formalism according to the acquisition parameters...
December 2015: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Xinmei Cao, Siji Nian, Yingchun Ye, Xu Wang, Qing Yuan
OBJECTIVE: To express human interleukin 4 (IL-4), select completely humanized anti-IL-4 single-chain antibodies (scFvs) from the completely humanized scFv library and identify their specificity. METHODS: With IPTG-induced pET102/IL-4/BL21, human IL-4 was synthesized, and then purified and identified. Completely humanized scFvs against IL-4 were expressed from the completely humanized antibody phage library, and positive clones were selected with human IL-4 as antigen...
December 2015: Xi Bao Yu Fen Zi Mian Yi Xue za Zhi, Chinese Journal of Cellular and Molecular Immunology
Guido Buonincontri, Stephen J Sawiak
PURPOSE: MR fingerprinting (MRF) can be used for quantitative estimation of physical parameters in MRI. Here, we extend the method to incorporate B1 estimation. METHODS: The acquisition is based on steady state free precession MR fingerprinting with a Cartesian trajectory. To increase the sensitivity to the B1 profile, abrupt changes in flip angle were introduced in the sequence. Slice profile and B1 effects were included in the dictionary and the results from two- and three-dimensional (3D) acquisitions were compared...
October 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Chiara Cordero, Patrizia Rubiolo, Luigi Cobelli, Gianluca Stani, Armando Miliazza, Matthew Giardina, Roger Firor, Carlo Bicchi
In this study, the first capillary flow technology reverse-inject differential flow modulator was implemented with different column configurations (lengths, diameters and stationary phase coupling) and detector combinations (mass spectrometry--MS and flame ionization detection--FID) to evaluate its potential in the quantitative profiling and fingerprinting of medium-to-highly complex essential oils. In particular, a parallel dual-secondary column dual-detection configuration that has shown to improve the information potential also with thermally modulated GC × GC platforms (MS identification reliability and accurate FID quantitation), was tested...
October 23, 2015: Journal of Chromatography. A
Yasuyuki Ueda, Junji Morishita, Shohei Kudomi, Katsuhiko Ueda
The purpose of our study is to investigate the feasibility of automated patient verification using multi-planar reconstruction (MPR) images generated from three-dimensional magnetic resonance (MR) imaging of the brain. Several anatomy-related MPR images generated from three-dimensional fast scout scan of each MR examination were used as biological fingerprint images in this study. The database of this study consisted of 730 temporal pairs of MR examination of the brain. We calculated the correlation value between current and prior biological fingerprint images of the same patient and also all combinations of two images for different patients to evaluate the effectiveness of our method for patient verification...
September 2016: Medical & Biological Engineering & Computing
Zalán Rajna, Janne Kananen, Anja Keskinarkaus, Tapio Seppänen, Vesa Kiviniemi
Recent studies pinpoint visually cued networks of avalanches with MEG/EEG data. Co-activation pattern (CAP) analysis can be used to detect single brain volume activity profiles and hemodynamic fingerprints of neuronal avalanches as sudden high signal activity peaks in classical fMRI data. In this study, we aimed to detect dynamic patterns of brain activity spreads with the use of ultrafast MR encephalography (MREG). MREG achieves 10 Hz whole brain sampling, allowing the estimation of spatial spread of an avalanche, even with the inherent hemodynamic delay of the BOLD signal...
2015: Frontiers in Human Neuroscience
Eric Y Pierre, Dan Ma, Yong Chen, Chaitra Badve, Mark A Griswold
PURPOSE: To reduce the acquisition time needed to obtain reliable parametric maps with Magnetic Resonance Fingerprinting. METHODS: An iterative-denoising algorithm is initialized by reconstructing the MRF image series at low image resolution. For subsequent iterations, the method enforces pixel-wise fidelity to the best-matching dictionary template then enforces fidelity to the acquired data at slightly higher spatial resolution. After convergence, parametric maps with desirable spatial resolution are obtained through template matching of the final image series...
June 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Young-Jae Jin, Rubal Dogra, In Woo Cheong, Giseop Kwak
Novel thermoresponsive sensor systems consisting of a molecular rotor (MR) and paraffin wax (PW) were developed for various thermometric and biometric identification applications. Polydiphenylacetylenes (PDPAs) coupled with long alkyl chains were used as MRs, and PWs of hydrocarbons having 16-20 carbons were utilized as phase-change materials. The PDPAs were successfully dissolved in the molten PWs and did not act as an impurity that prevents phase transition of the PWs. These PDPA-in-PW hybrids had almost the same enthalpies and phase-transition temperatures as the corresponding pure PWs...
July 8, 2015: ACS Applied Materials & Interfaces
Huihui Ye, Dan Ma, Yun Jiang, Stephen F Cauley, Yiping Du, Lawrence L Wald, Mark A Griswold, Kawin Setsompop
PURPOSE: We incorporate simultaneous multislice (SMS) acquisition into MR fingerprinting (MRF) to accelerate the MRF acquisition. METHODS: The t-Blipped SMS-MRF method is achieved by adding a Gz blip before each data acquisition window and balancing it with a Gz blip of opposing polarity at the end of each TR. Thus the signal from different simultaneously excited slices are encoded with different phases without disturbing the signal evolution. Furthermore, by varying the Gz blip area and/or polarity as a function of repetition time, the slices' differential phase can also be made to vary as a function of time...
May 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
(no author information available yet)
Current routine MRI examinations rely on the acquisition of qualitative images that have a contrast "weighted" for a mixture of (magnetic) tissue properties. Recently, a novel approach was introduced, namely MR Fingerprinting (MRF) with a completely different approach to data acquisition, post-processing and visualization. Instead of using a repeated, serial acquisition of data for the characterization of individual parameters of interest, MRF uses a pseudo randomized acquisition that causes the signals from different tissues to have a unique signal evolution or 'fingerprint' that is simultaneously a function of the multiple material properties under investigation...
April 2015: Insights Into Imaging
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