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Tognarelli JM, Dawood M, Shariff MI, Grover VP, Crossey MM, Cox IJ, Taylor-Robinson SD, McPhail MJ. Magnetic Resonance Spectroscopy: Principles and Techniques: Lessons for Clinicians. J Clin Exp Hepatol 2015; 5:320-8. [PMID: 26900274 PMCID: PMC4723643 DOI: 10.1016/j.jceh.2015.10.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 10/26/2015] [Indexed: 12/12/2022] Open
Abstract
Magnetic resonance spectroscopy (MRS) provides a non-invasive 'window' on biochemical processes within the body. Its use is no longer restricted to the field of research, with applications in clinical practice increasingly common. MRS can be conducted at high magnetic field strengths (typically 11-14 T) on body fluids, cell extracts and tissue samples, with new developments in whole-body magnetic resonance imaging (MRI) allowing clinical MRS at the end of a standard MRI examination, obtaining functional information in addition to anatomical information. We discuss the background physics the busy clinician needs to know before considering using the technique as an investigative tool. Some potential applications of hepatic and cerebral MRS in chronic liver disease are also discussed.
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Key Words
- CPMG, Carr-Purcell-Meiboom-Gill sequence
- CSI, chemical shift imaging
- FID, free induction decay
- K, Kelvin
- KEGG, Kyoto Encyclopedia for Genes and Genomes
- MR, magnetic resonance
- MRI, magnetic resonance imaging
- MRS, magnetic resonance spectroscopy
- MSEA, metabolite set enrichment analysis
- NMR, nuclear magnetic resonance
- NOESY, nuclear Overhauser enhancement spectroscopy
- PC, principal components
- PCA, principal components analysis
- PLS-DA, partial least squared discriminant analysis
- PRESS, point-resolved spectroscopy
- STEAM, stimulated echo acquisition mode
- T, Tesla
- T1, spin-lattice relaxation
- T2, spin-spin relaxation
- TE, echo time
- TMAO, trimethylamine N-oxide
- TR, repetition time
- magnetic resonance imaging
- magnetic resonance spectroscopy
- metabolomics
- nuclear magnetic resonance
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Affiliation(s)
- Joshua M. Tognarelli
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
- Address for correspondence: Joshua Tognarelli, Liver Unit, Department of Medicine, 10th Floor QEQM Wing, St Mary's Hospital, Imperial College London, Praed Street, London W2 1NY, United Kingdom. Tel.: +44 207 886 6454; fax: +44 207 402 2796.Liver Unit, Department of Medicine, 10th Floor QEQM Wing, St Mary's Hospital, Imperial College LondonPraed StreetLondonW2 1NYUnited Kingdom
| | - Mahvish Dawood
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Mohamed I.F. Shariff
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Vijay P.B. Grover
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Mary M.E. Crossey
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - I. Jane Cox
- The Foundation for Liver Research, Institute of Hepatology, 69-75 Chenies Mews, London WC1E 6HX, United Kingdom
| | - Simon D. Taylor-Robinson
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Mark J.W. McPhail
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
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Shariff MI, Tognarelli JM, Lewis MR, Want EJ, Mohamed FEZ, Ladep NG, Crossey MM, Khan SA, Jalan R, Holmes E, Taylor-Robinson SD. Plasma Lipid Profiling in a Rat Model of Hepatocellular Carcinoma: Potential Modulation Through Quinolone Administration. J Clin Exp Hepatol 2015; 5:286-94. [PMID: 26900269 PMCID: PMC4723654 DOI: 10.1016/j.jceh.2015.07.205] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 07/09/2015] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND/AIMS The primary aim of this study was to characterise the blood metabolic profile of hepatocellular carcinoma (HCC) in a rat model, and the secondary aim was to evaluate the effect of the quinolone, norfloxacin on metabolic profiles and exploring the role that gut sterilisation may have on HCC development. METHODS HCC was induced in 10 Fischer rats by administration of intra-peritoneal diethylnitrosamine (DEN) and oral N-nitrosomorpholine. Plasma was collected upon sacrifice. Five of these rats were concomitantly administered oral norfloxacin. Six Fischer non-treated rats acted as healthy controls. Proton nuclear magnetic resonance (NMR) spectra were acquired using a 600 MHz NMR system. RESULTS Control animals were 120 g heavier than diseased counterparts. Proton NMR spectra from diseased rats displayed significant decreases in lipoproteins, unsaturated fatty acids, acetyl-glycoprotein, acetoacetate, and glucose (P ≤ 0.001). Plasma citrate and formate levels were increased (P = 0.02). Norfloxacin appeared to abrogate this effect slightly. CONCLUSION The spectral profiles of plasma in rats with HCC display marked changes with relation to lipid metabolism and cellular turnover. Norfloxacin appears to moderate these metabolic alterations to a small degree.
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Key Words
- 1-D, one-dimensional
- 1H, human proton
- CPMG, Carr-Purcell-Meiboom-Gill 3B
- DEN, diethylnitrosamine
- FID, free induction decay
- HCC, hepatocellular carcinoma
- HDL, high-density lipoprotein
- LDL, low-density lipoprotein
- NMOR, N-nitrosomorpholine
- NMR spectroscopy
- NMR, nuclear magnetic resonance
- NOESY, nuclear overhauser effect spectroscopy
- PCA, principal components analysis
- PLS-DA, partial least squares discriminant analysis
- Q2, goodness of prediction
- R2, goodness of fit
- RD, relaxation delay
- RF, radiofrequency
- SBP, spontaneous bacterial peritonitis
- TLR-4, Toll-like receptor 4
- VLDL, very low-density lipoprotein
- hepatocellular carcinoma
- metabonomics
- norfloxacin
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Affiliation(s)
- Mohamed I.F. Shariff
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Joshua M. Tognarelli
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom,Address for correspondence: Joshua Tognarelli, Liver Unit, Department Of Medicine, 10th Floor QEQM Wing, St Mary's Hospital Campus, Imperial College London, South Wharf Street, London W2 1NY, United Kingdom. Tel.: +44 207 886 6454; fax: +44 207 724 9369.
| | - Matthew R. Lewis
- Department of Surgery and Cancer, Imperial College London, Division of Computational and Systems Medicine, London SW7 2AZ, United Kingdom
| | - Elizabeth J. Want
- Department of Surgery and Cancer, Imperial College London, Division of Computational and Systems Medicine, London SW7 2AZ, United Kingdom
| | | | - Nimzing G. Ladep
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom,Department of Surgery and Cancer, Imperial College London, Division of Computational and Systems Medicine, London SW7 2AZ, United Kingdom
| | - Mary M.E. Crossey
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom,Department of Surgery and Cancer, Imperial College London, Division of Computational and Systems Medicine, London SW7 2AZ, United Kingdom
| | - Shahid A. Khan
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Rajiv Jalan
- Department of Medicine, University College London, Royal Free Hospital, London NW3 2QG, United Kingdom
| | - Elaine Holmes
- Department of Surgery and Cancer, Imperial College London, Division of Computational and Systems Medicine, London SW7 2AZ, United Kingdom
| | - Simon D. Taylor-Robinson
- Liver Unit, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
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Grover VP, Tognarelli JM, Crossey MM, Cox IJ, Taylor-Robinson SD, McPhail MJ. Magnetic Resonance Imaging: Principles and Techniques: Lessons for Clinicians. J Clin Exp Hepatol 2015; 5:246-55. [PMID: 26628842 DOI: 10.1016/j.jceh.2015.08.001] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 08/10/2015] [Indexed: 12/12/2022] Open
Abstract
The development of magnetic resonance imaging (MRI) for use in medical investigation has provided a huge forward leap in the field of diagnosis, particularly with avoidance of exposure to potentially dangerous ionizing radiation. With decreasing costs and better availability, the use of MRI is becoming ever more pervasive throughout clinical practice. Understanding the principles underlying this imaging modality and its multiple applications can be used to appreciate the benefits and limitations of its use, further informing clinical decision-making. In this article, the principles of MRI are reviewed, with further discussion of specific clinical applications such as parallel, diffusion-weighted, and magnetization transfer imaging. MR spectroscopy is also considered, with an overview of key metabolites and how they may be interpreted. Finally, a brief view on how the use of MRI will change over the coming years is presented.
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Key Words
- ADC, apparent diffusion coefficient
- CSI, Chemical shift imaging
- DTI, diffusion tensor imaging
- DWI, Diffusion-weighted imaging
- FA, Fractional anisotropy
- FID, free induction decay
- MRI, magnetic resonance imaging
- MTR, MT ratios
- NMR, nuclear magnetic resonance
- PRESS, Point-resolved spectroscopy
- RA, relative anisotropy
- RF, radiofrequency
- SNR, signal-to-noise ratio
- STEAM, Stimulated echo acquisition mode
- TR, repetition time
- magnetic resonance imaging
- magnetic resonance spectroscopy
- medical physics
- nuclear magnetic resonance
- nuclear medicine
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