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Sodium (23Na) MRI of the Kidney: Experimental Protocol

James T Grist, Esben Søvsø Hansen, Frank G Zöllner, Christoffer Laustsen
2021 Msphere  
Repetition time (TR): Choose 2.5Â greater than the T 1 of sodium in free fluid (T 1 approx. 70 ms at 7 T). 3. Flip angle (FA): 90 . 4.  ...  Repetition time (TR): Choose 2.5Â greater than the T 1 of sodium in free fluid (T 1 approx. 70 ms at 7 T). Renal Sodium MRI: Experimental Protocol  ... 
doi:10.1007/978-1-0716-0978-1_28 pmid:33476018 fatcat:ut4chjhrajge7dbglm72upwsue

Sodium (23Na) MRI of the Kidney: Basic Concept

James T Grist, Esben Søvsø Hansen, Frank G Zöllner, Christoffer Laustsen
2021 Msphere  
þ b exp À TE T * 2,Long ! !  ...  It is currently thought that the shorter T * 2 component (1-5 ms at 3 T) is derived from the intracellular compartment, and the longer (10-30 ms at 3 T) from the extracellular compartment [9, 16] .  ... 
doi:10.1007/978-1-0716-0978-1_15 pmid:33476005 fatcat:mhdveizzpfaerir2m5b4u2qiy4

Analysis Protocol for Renal Sodium (23Na) MR Imaging

James T Grist, Esben Søvsø Szocska Hansen, Frank G Zöllner, Christoffer Laustsen
2021 Msphere  
T * 2 relaxation maps can be calculated from multiecho GRE data acquired in the same acquisition. Theoretical considerations and acquisition protocols are detailed in the chapters by Grist JT et al.  ...  * 2,Short þ b e À TE T * 2,Long ð2Þ where a and b are the relative pool sizes, and T * 2,Short and T * 2,Long are the pool T * 2 constants (ms), with the constraints that a + b ¼ 1, and T * 2,Short > T  ... 
doi:10.1007/978-1-0716-0978-1_41 pmid:33476031 fatcat:hsy2amcejfasle4rn2jpzaheom

Extracellular Lactate: A Novel Measure of T Cell Proliferation

James T. Grist, Lorna B. Jarvis, Zoya Georgieva, Sara Thompson, Harpreet Kaur Sandhu, Keith Burling, Ashley Clarke, Sarah Jackson, Mark Wills, Ferdia A. Gallagher, Joanne L. Jones
2017 Journal of Immunology  
F low Cytometric Suppression Index ¼ T V 670 Low Stim 2 T V 670 Low Sup T V 670 Low Stim ; ð2Þ where T V 670 Low Stim is the proportion of proliferating V670 low Teffs in the stimulated culture, and T  ...  Lactate Suppression Index ¼ T S 2 ðT Sup 2 T Reg;Stim Þ T S ð1Þ Eq. 1 shows the suppression index calculated from the extracellular lactate measurements, where T S is the lactate concentration in a stimulated  ... 
doi:10.4049/jimmunol.1700886 pmid:29288205 pmcid:PMC5776880 fatcat:sb7drqfdd5coxkkt2s6g4pbos4

The detection of acute kidney injury with hyperpolarized 13C Urea and multi-exponential fitting [article]

James T Grist, Christian Østergaard Mariager, Haiyun Qi, Per Mose Nielsen, Christoffer Laustsen
2019 arXiv   pre-print
is performed by decomposing multi-echo data into discrete relaxation (here T2) components through an inverse Laplacian transform as shown in equation 1.1. ( ) = ∑ g(k)exp (− /0 / 1,3 ) 4 5 1.1 Where z(t)  ...  Differences in the % of mono-, and bi-exponential voxels between healthy and IRI kidneys was assessed using a shapiro-wilk test and either a Mann-Wintney U test or unpaired t-test if normally distributed  ... 
arXiv:1910.10963v1 fatcat:2mkfiwpb7fdjfl6mmcza4mc6cm

Hyperpolarized 13 C magnetic resonance imaging for noninvasive assessment of tissue inflammation

Stephanie Anderson, James T Grist, Andrew Lewis, Damian J Tyler
2020 NMR in Biomedicine  
memory, naïve and regulatory T cell subsets predominately rely on fatty acid oxidation to maintain their energy demands; however, the increased energy requirements of activated T cell populations lead  ...  A recent study of soluble anti-CD28-activated human T cells demonstrated the applicability of hyperpolarized 13 C MRS for measurements of immune cell function. 56 Stimulated regulatory T cells exhibit  ... 
doi:10.1002/nbm.4460 pmid:33291188 pmcid:PMC7900961 fatcat:6rgxvpou4jebxbo3wzk4kksrii

Silicon photonic micro-disk resonators for label-free biosensing

Samantha M. Grist, Shon A. Schmidt, Jonas Flueckiger, Valentina Donzella, Wei Shi, Sahba Talebi Fard, James T. Kirk, Daniel M. Ratner, Karen C. Cheung, Lukas Chrostowski
2013 Optics Express  
Silicon photonic biosensors are highly attractive for multiplexed Lab-on-Chip systems. Here, we characterize the sensing performance of 3 µm TE-mode and 10 µm dual TE/TM-mode silicon photonic micro-disk resonators and demonstrate their ability to detect the specific capture of biomolecules. Our experimental results show sensitivities of 26 nm/RIU and 142 nm/RIU, and quality factors of 3.3x10 4 and 1.6x10 4 for the TE and TM modes, respectively. Additionally, we show that the large disks contain
more » ... both TE and TM modes with differing sensing characteristics. Finally, by serializing multiple disks on a single waveguide bus in a CMOS compatible process, we demonstrate a biosensor capable of multiplexed interrogation of biological samples. , "Zwitterionic polymermodified silicon microring resonators for label-free biosensing in undiluted humanplasma," Biosens. Bioelectron. 42, 100-105 (2013). 18. I. White, H. Zhu, J. Suter, and X. Fan, "Label-free biosensing with the optofluidic ring resonator," in Advanced
doi:10.1364/oe.21.007994 pmid:23571890 fatcat:hj2yzqqgkbfyfdorgh2j7ox2rq

13C Pyruvate Transport Across the Blood-Brain Barrier in Preclinical Hyperpolarised MRI

Jack J. Miller, James T. Grist, Sébastien Serres, James R. Larkin, Angus Z. Lau, Kevin Ray, Katherine R. Fisher, Esben Hansen, Rasmus Stilling Tougaard, Per Mose Nielsen, Jakob Lindhardt, Christoffer Laustsen (+3 others)
2018 Scientific Reports  
In comparison to the work of Hurd et al., this work was performed at higher field (7 T vs 3 T), resulting in a reduction in the available ⁎ T 2 for imaging and additionally a reduction in T 1 , similarly  ...  experiments compared to those at 11.7 T.  ... 
doi:10.1038/s41598-018-33363-5 pmid:30305655 pmcid:PMC6180068 fatcat:o6dyv3rvbrbx3cwwd6v4sokgra

Hyperpolarized 129Xe MRI Abnormalities in Dyspneic Participants 3 Months after COVID-19 Pneumonia: Preliminary Results

James T. Grist, Mitchell Chen, Guilhem J. Collier, Betty Raman, Gabriele AbuEid, Anthony McIntyre, Violet Matthews, Emily Fraser, Ling-Pei Ho, Jim M. Wild, Fergus Gleeson
2021 Radiology  
SARS-CoV-2 targets angiotensin-converting enzyme 2 (ACE2) expressing cells in the respiratory tract. There are reports of breathlessness in patients many months post-infection. Purpose This study aimed to determine if hyperpolarized 129Xe MRI (XeMRI) imaging could identify the possible cause of breathlessness in patients three months after hospital discharge following COVID-19 infection. Materials and Methods This prospective study was undertaken between August and December 2020, with patients
more » ... nd healthy control volunteers enrolled. All patients underwent: lung function tests; ventilation and dissolved phase XeMRI, with the mean Red Blood Cell (RBC):Tissue Plasma (TP) ratio to be calculated; and a low dose chest CT scored for the degree of post-COVID-19 abnormalities. Healthy controls underwent XeMRI. The intraclass correlation coefficient was calculated for volunteer and patient scans, to assess repeatability. A Wilcoxon rank-sum test and Cohen's effect size calculated to assess for differences between RBC:TP in patient and controls. Results 9 patients (mean age 57±7 years, Male = 6) and 5 volunteers (29 ± 3 years, Female = 5) were enrolled. Patient mean time from hospital discharge was 169, range 116-254 days. There was a difference in RBC:TP between patients and controls (0.3 ± 0.1 versus 0.5 ± 0.1, respectively, p = 0.001, effect size = 1.36). There was significant difference between the RBC and gas phase spectral full width at half maximum (FWHM) between volunteers and patients (median ± 95 % confidence interval, 567 ± 1 vs 507 ± 81, p = 0.002 and 104 ± 2 vs 122 ± 17, p = 0.004, respectively). Results were reproducible with Intraclass Correlation Coefficients of 0.82 and 0.88 for patients and volunteers respectively. Participants had normal or near normal CT scans, mean 7/25, range 0-10/25. Conclusion Xe MRI showed alveolar-capillary diffusion limitation in all 9 post COVID-19 pneumonia patients despite normal or nearly normal CT scans. See also the editorial by Dietrich.
doi:10.1148/radiol.2021210033 pmid:34032513 pmcid:PMC8168952 fatcat:a4upl6hc7zfdnbmweh6wd5zlki

Brain Tumor Diagnosis Using Machine Learning, Convolutional Neural Networks, Capsule Neural Networks and Vision Transformers, Applied to MRI: A Survey

Andronicus A. Akinyelu, Fulvio Zaccagna, James T. Grist, Mauro Castelli, Leonardo Rundo
2022 Journal of Imaging  
Used data augmentation. [75] 2020 T 1 w, T 1 w post GBCA, T 2 w, FLAIR U-Net architecture, GANs GANs was used to generate synthetic images for four modalities of MRI: T 1 , T1e, T 2 , FLAIR.  ...  They used a pairwise generative adversarial network (GAN) to generate synthetic MR images for four types of MRI's techniques, namely: T 1 w, GBCA, T 1 w (T 1 w post GBCA), T 2 w, and T 2 fluid-attenuated  ... 
doi:10.3390/jimaging8080205 pmid:35893083 pmcid:PMC9331677 fatcat:767d3te7gjfotabdwcy7ce2ohm

Non-invasive assessment of glioma microstructure using VERDICT MRI: correlation with histology

Fulvio Zaccagna, Frank Riemer, Andrew N. Priest, Mary A. McLean, Kieren Allinson, James T. Grist, Carmen Dragos, Tomasz Matys, Jonathan H. Gillard, Colin Watts, Stephen J. Price, Martin J. Graves (+1 others)
2019 European Radiology  
MRI acquisition MRI examinations were performed using a 3.0-T clinical scanner and a 12-channel head coil (Discovery MR750; GE Healthcare).  ...  the original VERDICT model is designed to compute the intracellular, intravascular and extracellular-extravascular spaces in an animal model of prostate cancer at a pre-clinical field strength of 9.4 T  ... 
doi:10.1007/s00330-019-6011-8 pmid:30888488 pmcid:PMC6719328 fatcat:j6rc4dmzx5hglknouddllzgawi

Imaging and treatment of brain tumors through molecular targeting: recent clinical advances

Fulvio Zaccagna, James T. Grist, Natale Quartuccio, Frank Riemer, Francesco Fraioli, Corradina Caracò, Richard Halsey, Yazeed Aldalilah, Charles H. Cunningham, Tarik F. Massoud, Luigi Aloj, Ferdia A. Gallagher
2021 European Journal of Radiology  
Adapted with permission from Grist et al. [86] . either of endogenous or exogenous origin [97] .  ...  (A) Axial FLAIR, (B) axial T 1 -weighted (T 1 W) after injection of a gadolinium-based contrast agent (GBCA) and (C) axial fused [ 18 F]DOPA /T 1 W post GBCA.  ... 
doi:10.1016/j.ejrad.2021.109842 fatcat:2rgmoia4kvdbpnzuar62bmladm

Predicting Survival in Patients with Brain Tumors: Current State-of-the-Art of AI Methods Applied to MRI

Christian di Noia, James T. Grist, Frank Riemer, Maria Lyasheva, Miriana Fabozzi, Mauro Castelli, Raffaele Lodi, Caterina Tonon, Leonardo Rundo, Fulvio Zaccagna
2022 Diagnostics  
[92] focused on GBM, while Grist et al. [93] focused on paediatric brain tumors.  ...  The authors generated post-contrast T 1 w synthetic MR images from pre-contrast T 1 w MR images using a deep CNN (dCNN).  ... 
doi:10.3390/diagnostics12092125 pmid:36140526 pmcid:PMC9497964 fatcat:5wdx7xbttbfcdpwwsfnf3jbjau

Combining multi-site Magnetic Resonance Imaging with machine learning predicts survival in paediatric brain tumours [article]

James T. Grist, Stephanie Withey, Christopher Bennett, Heather E. L. Rose, Lesley MacPherson, Adam Oates, Stephen Powell, Jan Novak, Laurence Abernethy, Barry Pizer, Simon Bailey, Steven C. Clifford (+6 others)
2020 arXiv   pre-print
Differences in high-/low-risk (defined below) participants were assessed using unpaired two-tailed t-tests or Mann-Whitney U test, depending on data normality.  ...  Subsequently, differences in clinical and imaging features between high-and low-grade tumours were assessed using unpaired t-tests or Mann-Whitney U tests, where appropriate.  ... 
arXiv:2004.09849v1 fatcat:hsd4fzdunfaqhi2e7atxwl2frq

IMG-06. PREDICTING SURVIVAL FROM PERFUSION AND DIFFUSION MRI BY MACHINE LEARNING

James T Grist, Stephanie Withey, Christopher Bennett, Heather Rose, Lesley MacPherson, Adam Oates, Stephen Powell, Jan Novak, Laurence Abernethy, Barry Pizer, Simon Bailey, Dipayan Mitra (+5 others)
2020 Neuro-Oncology  
LOW GRADE GLIOMA Vickyanne Carruthers 1 , Kathryn Siddle 1 , Gail Halliday 1 , Simon Bailey 1,2 , and Rebecca Hill 1 ; 1 Newcastle Upon Tyne Hospitals Trust, Newcastle Upon Tyne, United Kingdom, 2 Sir James  ... 
doi:10.1093/neuonc/noaa222.342 fatcat:exjxnxiaszdhtom3zl3u2yhv2u
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