NMR in Biomedicine

Cover image for Vol. 24 Issue 9

November 2011

Volume 24, Issue 9

Pages 1029–1180

  1. Research Articles

    1. Top of page
    2. Research Articles
    1. Substrate selection in hearts subjected to ischemia/reperfusion: role of cardioplegic solutions and gender (pages 1029–1037)

      Marco G. Alves, Paulo J. Oliveira and Rui A. Carvalho

      Version of Record online: 28 JAN 2011 | DOI: 10.1002/nbm.1640

      Thumbnail image of graphical abstract

      Glucose and lactate suffer a distinct metabolic fate after ischemia/reperfusion (I/R), which is related to both the cardioplegic solution used during ischemia and gender. Hearts from females appear to be less sensitive to I/R injury, and preservation in histidine buffer solution is as effective as preservation in Celsior.

    2. 7-T 1H MRS with adiabatic refocusing at short TE using radiofrequency focusing with a dual-channel volume transmit coil (pages 1038–1046)

      V.O. Boer, A.L.H.M.W. van Lier, J.M. Hoogduin, J.P. Wijnen, P.R. Luijten and D.W.J. Klomp

      Version of Record online: 4 FEB 2011 | DOI: 10.1002/nbm.1641

      Thumbnail image of graphical abstract

      By driving a standard volume coil with two radiofrequency (RF) amplifiers, focusing the Bmath image field in a certain location and using high-bandwidth adiabatic refocusing pulses, a semi-localized by adiabatic selective refocusing (semi-LASER) localization is shown to be feasible at short TE in the human brain with full signal acquisition and a low chemical shift displacement artifact at 7 T.

    3. Quantification of myocardial blood flow and flow reserve in rats using arterial spin labeling MRI: comparison with a fluorescent microsphere technique (pages 1047–1053)

      Alexis Jacquier, Frank Kober, Soksithikun Bun, Roch Giorgi, Patrick J. Cozzone and Monique Bernard

      Version of Record online: 25 JAN 2011 | DOI: 10.1002/nbm.1645

      Thumbnail image of graphical abstract

      This study shows that Look-Locker flow-sensitive alternating inversion recovery gradient-echo (LLFAIRGE-ASL) allows quantification of myocardial blood flow (MBF) reserve in freely breathing rats under isoflurane. Using both techniques LLFAIRGE and fluorescent microspheres (FM), and under similar physiologic conditions, we measured the MBF reserve to be approximately 2.5. There were no significant differences in MBF measures obtained with LLFAIRGE and FM, at rest and under adenosine.

    4. In vivo detection of intermediate metabolic products of [1-13C]ethanol in the brain using 13C MRS (pages 1054–1062)

      Yun Xiang and Jun Shen

      Version of Record online: 11 FEB 2011 | DOI: 10.1002/nbm.1653

      Thumbnail image of graphical abstract

      Co-administration of [1-13C]ethanol and [13C6]-D-glucose allows the simultaneous detection of the labeling kinetics of brain metabolites by singly labeled [1-13C]ethanol and uniformly labeled glucose. In contrast with labeling by [13C6]-D-glucose, which produced doublets of carboxylic/amide carbons with a J coupling constant of 51 Hz, the simultaneously detected glutamate and glutamine singlets were labeled by [1-13C]ethanol.

    5. Age-dependent brain temperature decline assessed by diffusion-weighted imaging thermometry (pages 1063–1067)

      Koji Sakai, Kei Yamada, Susumu Mori, Naozo Sugimoto and Tsunehiko Nishimura

      Version of Record online: 28 JAN 2011 | DOI: 10.1002/nbm.1656

      Thumbnail image of graphical abstract

      Brain metabolism declines with age, but cerebral blood flow (CBF) is less age dependent. We therefore hypothesized that brain temperature would decline with age, and measured the temperatures of the lateral ventricles in healthy volunteers by diffusion-weighted imaging thermometry. The mean lateral ventricular temperatures in healthyvolunteers showed a linear decrease with age, presumably caused by asynchronous declines in brain metabolism and CBF.

    6. Transmit gain calibration for nonproton MR using the Bloch–Siegert shift (pages 1068–1072)

      Rolf F. Schulte, Laura Sacolick, Martin H. Deppe, Martin A. Janich, Markus Schwaiger, Jim M. Wild and Florian Wiesinger

      Version of Record online: 8 MAR 2011 | DOI: 10.1002/nbm.1657

      Thumbnail image of graphical abstract

      Transmit gain (Bmath image) calibration for nonproton MR is usually time consuming and difficult, especially in the case of hyperpolarised MR. In the current work, transmit gain calibration was implemented on the basis of the Bloch–Siegert phase shift. From the same data, the centre frequency (f0), line broadening (lb) and signal-to-noise ratio (SNR) could also be determined. The T1 and B0 insensitivity, and the wide range of Bmath image values over which this technique is effective, make it well suited for nonproton applications. Examples are shown for hyperpolarised 13C and 3He applications.

    7. Comparison of hyperpolarized 3He MRI with Xe-enhanced computed tomography imaging for ventilation mapping of rat lung (pages 1073–1080)

      Giles E. Santyr, Marcus J. Couch, Wilfred W. Lam, Alexei Ouriadov, Maria Drangova, David G. McCormack and David W. Holdsworth

      Version of Record online: 28 JAN 2011 | DOI: 10.1002/nbm.1659

      Thumbnail image of graphical abstract

      3He MR was quantitatively compared with Xe-enhanced computed tomography (Xe-CT) imaging for regional ventilation mapping of the rat lung. Ventilation values measured for the whole lung using 3He MR and Xe-CT were not significantly different (P > 0.05), but ventilation gradients calculated in the superior/inferior direction were significantly different for the two methods (P < 0.05). These regional differences in ventilation measurements may be caused by the manner in which the gas contrast agents distribute physiologically and/or the imaging modality.

    8. High-field MRS of the human brain at short TE and TR (pages 1081–1088)

      Vincent O. Boer, Jeroen C.W. Siero, Hans Hoogduin, Jetse S. van Gorp, Peter R. Luijten and Dennis W.J. Klomp

      Version of Record online: 10 FEB 2011 | DOI: 10.1002/nbm.1660

      Thumbnail image of graphical abstract

      MRS at 7 tesla is shown with limited chemical shift dispersion artifacts, short echo time and full signal acquisition using a pulse-acquire CSI approach. Sensitivity was maximized using a very short echo time and a short repetition time which was realized using low power lipid and water suppression in combination with a cost function guided shimming algorithm, leading to a highly time-efficient sequence allowing high-resolution MRS of the human brain.

    9. Reproducibility of prefrontal γ-aminobutyric acid measurements with J-edited spectroscopy (pages 1089–1098)

      Matthew Geramita, Jan Willem van der Veen, Alan S. Barnett, Antonina A. Savostyanova, Jun Shen, Daniel R. Weinberger and Stefano Marenco

      Version of Record online: 3 FEB 2011 | DOI: 10.1002/nbm.1662

      Thumbnail image of graphical abstract

      In this study, we quantified the reproducibility of an in vivo MRS acquisition and data processing method to measure γ-aminobutyric acid + macromolecules (GABA +) in the anterior cingulate cortex and right frontal white matter. To explore the dependence of metabolite concentrations on voxel composition, we extrapolated GABA + values to pure gray and pure white matter. We found that GABA + quantification was highly reproducible and that GABA + concentrations were significantly higher in gray than in white matter.

    10. 1H-MRS can detect aberrant glycosylation in tumour cells: a study of the HeLa cell line (pages 1099–1110)

      Alessandra Palma, Sveva Grande, Antonella Rosi, Anna Maria Luciani, Laura Guidoni and Vincenza Viti

      Version of Record online: 3 FEB 2011 | DOI: 10.1002/nbm.1665

      Thumbnail image of graphical abstract

      MR signals from N-acetylgalactosamine (GalNAc) and from fucose in HeLa cells were identified by detecting: (i) a low-field signal in 1D spectra assigned to the NH of GalNAc and (ii) some cross peaks assigned to fucose in 2D spectra. The assignment of the GalNAc signal was confirmed by treatment with NH4Cl. A common origin for the GalNAc and fucose resonances attributing them to aberrantly processed mucin can be inferred from the present results.

    11. Background suppression in arterial spin labeling MRI with a separate neck labeling coil (pages 1111–1118)

      Qiang Shen and Timothy Q. Duong

      Version of Record online: 4 FEB 2011 | DOI: 10.1002/nbm.1666

      Thumbnail image of graphical abstract

      This study presents a novel approach of background in association with a separate neck radiofrequency coil for continuous arterial spin labeling and a brain radiofrequency coil for background suppression with the inversion pulse placed before spin labeling. Improved basal cerebral blood flow (CBF) and CBF-based fMRI sensitivity could lead to more accurate CBF quantification and should prove useful for imaging low CBF conditions such as in white matter and stroke.

    12. MRI evaluation of axonal reorganization after bone marrow stromal cell treatment of traumatic brain injury (pages 1119–1128)

      Quan Jiang, Changsheng Qu, Michael Chopp, Guang Liang Ding, Siamak P. Nejad- Davarani, Joseph A. Helpern, Jens H. Jensen, Zheng Gang Zhang, Lian Li, Mei Lu, David Kaplan, Jiani Hu, Yimin Shen, Zhifeng Kou, Qingjiang Li, Shiyang Wang and Asim Mahmood

      Version of Record online: 23 MAR 2011 | DOI: 10.1002/nbm.1667

      Thumbnail image of graphical abstract

      We treated traumatic brain injury with bone marrow stromal cells (MSCs) and evaluated the effect of treatment on white matter reorganization using MRI. Treatment with MSCs increased fractional anisotropy (FA) in the recovery regions, lowered T2 in the core region, decreased lesion volume and improved functional recovery compared with untreated controls. The white matter reorganized regions corresponded well with the labeled cells. The apparent kurtosis coefficient detected additional axonal remodeling regions with crossing axons, confirmed by immunohistological staining, compared with FA.

    13. A novel background field removal method for MRI using projection onto dipole fields (PDF) (pages 1129–1136)

      Tian Liu, Ildar Khalidov, Ludovic de Rochefort, Pascal Spincemaille, Jing Liu, A. John Tsiouris and Yi Wang

      Version of Record online: 8 MAR 2011 | DOI: 10.1002/nbm.1670

      Thumbnail image of graphical abstract

      In this article, we report an observation that the magnetic field for a dipole outside a given region of interest (ROI) is approximately orthogonal to the magnetic field of a dipole inside the ROI. Accordingly, we propose a nonparametric background field removal technique based on projection onto dipole fields (PDF). This novel PDF background removal technique was validated in a numerical simulation and a phantom experiment and was applied in human brain imaging, demonstrating substantial improvement in background field removal compared with the commonly used high-pass filtering method.

    14. Assessment of glycosaminoglycan distribution in human lumbar intervertebral discs using chemical exchange saturation transfer at 3 T: feasibility and initial experience (pages 1137–1144)

      Mina Kim, Queenie Chan, Marina-Portia Anthony, Kenneth M.C. Cheung, Dino Samartzis and Pek-Lan Khong

      Version of Record online: 8 MAR 2011 | DOI: 10.1002/nbm.1671

      Thumbnail image of graphical abstract

      The feasibility of in vivo glycosaminoglycan chemical exchange saturation transfer (gagCEST) quantification was investigated for the first time in human lumbar intervertebral discs (IVDs) using a clinical MRI scanner. Our data showed robust contrast between the nucleus pulposus (NP) and the annulus fibrosus, a higher signal in the central relative to peripheral NP and a trend of decreasing CEST values from upper to lower disc levels with successful B0 inhomogeneity correction. Our initial findings suggest that it would be worthwhile to perform direct correlation studies between CEST and glycosaminoglycans using cadaver samples, and to extend this novel technique to studies on patients with degenerative discs to better understand its distinct imaging features relative to conventional techniques.

    15. Ursodeoxycholic acid treatment of hepatic steatosis: a 13C NMR metabolic study (pages 1145–1158)

      Patrícia M. Nunes, John G. Jones, Anabela P. Rolo, Carlos M. M. Palmeira and Rui A. Carvalho

      Version of Record online: 27 APR 2011 | DOI: 10.1002/nbm.1672

      Thumbnail image of graphical abstract

      In this study we applied 13C NMR isotopomer analysis to study hepatic fatty-acid catabolism in Zucker obese rats. It was observed that obese animals have lower fatty-acid oxidation and after four weeks of oral treatment with Ursodeoxycholic acid, the fatty acid catabolism is significantly improved.

    16. Preclinical study of treatment response in HCT-116 cells and xenografts with 1H-decoupled 31P MRS (pages 1159–1168)

      Moses M. Darpolor, Peter T. Kennealey, H. Carl Le, Kristen L. Zakian, Ellen Ackerstaff, Asif Rizwan, Jin-Hong Chen, Elliot B. Sambol, Gary K. Schwartz, Samuel Singer and Jason A. Koutcher

      Version of Record online: 24 MAR 2011 | DOI: 10.1002/nbm.1674

      Thumbnail image of graphical abstract

      In vivo1H-decoupled 31P MRS indirectly measures choline kinase activity by the decrease in phosphocholine that may be a potential indicator of early tumor response to the sequential treatment of irinotecan followed by flavopiridol in longitudinal study. Results indicate that irinotecan facilitates G2/M HCT-116 cells arrest, and a follow-up treatment with flavopiridol induces these G2/M-arrested cells to synergistically undergo apoptosis.

    17. A comparative study of dynamic contrast-enhanced MRI parameters as biomarkers for anti-angiogenic drug therapy (pages 1169–1180)

      Tong San Koh, Choon Hua Thng, Septian Hartono, Bee Choo Tai, Helmut Rumpel, Ai Bee Ong, Norita Sukri, Ross A. Soo, Chuing Ing Wong, Albert S. C. Low, Rod A. Humerickhouse and Boon Cher Goh

      Version of Record online: 23 MAR 2011 | DOI: 10.1002/nbm.1680

      Thumbnail image of graphical abstract

      Dynamic contrast-enhanced (DCE) MRI parameters derived from three tracer kinetics methods were compared in a Phase I trial of an anti-angiogenic drug ABT-869, by correlating the parameters to drug exposure and patient outcome. Results show that certain DCE MRI parameters which correlated with drug exposure and are predictive of tumor progression, can potentially serve as biomarkers in anti-angiogenic drug trials.

SEARCH

SEARCH BY CITATION