The z-spectrum from human blood at 7T
Chemical Exchange Saturation Transfer (CEST) has been used to assess healthy and pathological tissue in both animals and humans. However, the CEST signal from blood has not been fully assessed. This paper presents the CEST and nuclear Overhauser enhancement (NOE) signals detected in human blood meas...
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| Format: | Article |
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Elsevier
2018
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| Online Access: | https://eprints.nottingham.ac.uk/47563/ |
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| author | Shah, Simon M. Mougin, Olivier E. Carradus, Andrew J. Geades, Nicolas Dury, Richard Morley, William Gowland, Penny A. |
| author_facet | Shah, Simon M. Mougin, Olivier E. Carradus, Andrew J. Geades, Nicolas Dury, Richard Morley, William Gowland, Penny A. |
| author_sort | Shah, Simon M. |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | Chemical Exchange Saturation Transfer (CEST) has been used to assess healthy and pathological tissue in both animals and humans. However, the CEST signal from blood has not been fully assessed. This paper presents the CEST and nuclear Overhauser enhancement (NOE) signals detected in human blood measured via z-spectrum analysis. We assessed the effects of blood oxygenation levels, haematocrit, cell structure and pH upon the z-spectrum in ex vivo human blood for different saturation powers at 7T. The data were analysed using Lorentzian difference (LD) model fitting and AREX (to compensate for changes in T1), which have been successfully used to study CEST effects in vivo. Full Bloch-McConnell fitting was also performed to provide an initial estimate of exchange rates and transverse relaxation rates of the various pools. CEST and NOE signals were observed at 3.5 ppm, -1.7ppm and -3.5 ppm and were found to originate primarily from the red blood cells (RBCs), although the amide proton transfer (APT) CEST effect, and NOEs showed no dependence upon oxygenation levels. Upon lysing, the APT and NOE signals fell significantly. Different pH levels in blood resulted in changes in both the APT and NOE (at -3.5ppm), which suggests that this NOE signal is in part an exchange relayed process. These results will be important for assessing in vivo z-spectra. |
| first_indexed | 2025-11-14T20:06:05Z |
| format | Article |
| id | nottingham-47563 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T20:06:05Z |
| publishDate | 2018 |
| publisher | Elsevier |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-475632020-05-04T19:32:33Z https://eprints.nottingham.ac.uk/47563/ The z-spectrum from human blood at 7T Shah, Simon M. Mougin, Olivier E. Carradus, Andrew J. Geades, Nicolas Dury, Richard Morley, William Gowland, Penny A. Chemical Exchange Saturation Transfer (CEST) has been used to assess healthy and pathological tissue in both animals and humans. However, the CEST signal from blood has not been fully assessed. This paper presents the CEST and nuclear Overhauser enhancement (NOE) signals detected in human blood measured via z-spectrum analysis. We assessed the effects of blood oxygenation levels, haematocrit, cell structure and pH upon the z-spectrum in ex vivo human blood for different saturation powers at 7T. The data were analysed using Lorentzian difference (LD) model fitting and AREX (to compensate for changes in T1), which have been successfully used to study CEST effects in vivo. Full Bloch-McConnell fitting was also performed to provide an initial estimate of exchange rates and transverse relaxation rates of the various pools. CEST and NOE signals were observed at 3.5 ppm, -1.7ppm and -3.5 ppm and were found to originate primarily from the red blood cells (RBCs), although the amide proton transfer (APT) CEST effect, and NOEs showed no dependence upon oxygenation levels. Upon lysing, the APT and NOE signals fell significantly. Different pH levels in blood resulted in changes in both the APT and NOE (at -3.5ppm), which suggests that this NOE signal is in part an exchange relayed process. These results will be important for assessing in vivo z-spectra. Elsevier 2018-02-15 Article PeerReviewed Shah, Simon M., Mougin, Olivier E., Carradus, Andrew J., Geades, Nicolas, Dury, Richard, Morley, William and Gowland, Penny A. (2018) The z-spectrum from human blood at 7T. NeuroImage, 167 . pp. 31-40. ISSN 1095-9572 Chemical Exchange Saturation Transfer (CEST) Nuclear Overhauser Enhancement (NOE) z-spectrum Magnetisation transfer Blood relaxometry http://www.sciencedirect.com/science/article/pii/S105381191730887X doi:10.1016/j.neuroimage.2017.10.053 doi:10.1016/j.neuroimage.2017.10.053 |
| spellingShingle | Chemical Exchange Saturation Transfer (CEST) Nuclear Overhauser Enhancement (NOE) z-spectrum Magnetisation transfer Blood relaxometry Shah, Simon M. Mougin, Olivier E. Carradus, Andrew J. Geades, Nicolas Dury, Richard Morley, William Gowland, Penny A. The z-spectrum from human blood at 7T |
| title | The z-spectrum from human blood at 7T |
| title_full | The z-spectrum from human blood at 7T |
| title_fullStr | The z-spectrum from human blood at 7T |
| title_full_unstemmed | The z-spectrum from human blood at 7T |
| title_short | The z-spectrum from human blood at 7T |
| title_sort | z-spectrum from human blood at 7t |
| topic | Chemical Exchange Saturation Transfer (CEST) Nuclear Overhauser Enhancement (NOE) z-spectrum Magnetisation transfer Blood relaxometry |
| url | https://eprints.nottingham.ac.uk/47563/ https://eprints.nottingham.ac.uk/47563/ https://eprints.nottingham.ac.uk/47563/ |