32 results on '"Marjanska, M."'
Search Results
2. Segmenting the subregions of the human hippocampus at 7 Tesla
- Author
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Chupin, M, Lehéricy, S, Hasboun, D, Colliot, O, Goerke, U, Marjanska, M, Ugurbil, K, and van der Moortele, P F
- Published
- 2009
- Full Text
- View/download PDF
3. Methodological consensus on clinical proton MRS of the brain: Review and recommendations
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Wilson, M., Andronesi, O., Barker, P.B., Bartha, R., Bizzi, A., Bolan, P.J., Brindle, K.M., Choi, I.Y., Cudalbu, C., Dydak, U., Emir, U.E., Gonzalez, R.G., Gruber, S., Gruetter, R., Gupta, R.K., Heerschap, A., Henning, A., Hetherington, H.P., Huppi, P.S., Hurd, R.E., Kantarci, K., Kauppinen, R.A., Klomp, D.W.J., Kreis, R., Kruiskamp, M.J., Leach, M.O., Lin, A.P., Luijten, P.R., Marjanska, M., Maudsley, A.A., Meyerhoff, D.J., Mountford, C.E., Mullins, P.G., Murdoch, J.B., Nelson, S.J., Noeske, R., Oz, G., Pan, J.W., Peet, A.C., Poptani, H., Posse, S., Ratai, E.M., Salibi, N., Scheenen, T.W.J., Smith, I.C.P., Soher, B.J., Tkac, I., Vigneron, D.B., Howe, F.A., Wilson, M., Andronesi, O., Barker, P.B., Bartha, R., Bizzi, A., Bolan, P.J., Brindle, K.M., Choi, I.Y., Cudalbu, C., Dydak, U., Emir, U.E., Gonzalez, R.G., Gruber, S., Gruetter, R., Gupta, R.K., Heerschap, A., Henning, A., Hetherington, H.P., Huppi, P.S., Hurd, R.E., Kantarci, K., Kauppinen, R.A., Klomp, D.W.J., Kreis, R., Kruiskamp, M.J., Leach, M.O., Lin, A.P., Luijten, P.R., Marjanska, M., Maudsley, A.A., Meyerhoff, D.J., Mountford, C.E., Mullins, P.G., Murdoch, J.B., Nelson, S.J., Noeske, R., Oz, G., Pan, J.W., Peet, A.C., Poptani, H., Posse, S., Ratai, E.M., Salibi, N., Scheenen, T.W.J., Smith, I.C.P., Soher, B.J., Tkac, I., Vigneron, D.B., and Howe, F.A.
- Abstract
Contains fulltext : 205502.pdf (publisher's version ) (Closed access), Proton MRS ((1) H MRS) provides noninvasive, quantitative metabolite profiles of tissue and has been shown to aid the clinical management of several brain diseases. Although most modern clinical MR scanners support MRS capabilities, routine use is largely restricted to specialized centers with good access to MR research support. Widespread adoption has been slow for several reasons, and technical challenges toward obtaining reliable good-quality results have been identified as a contributing factor. Considerable progress has been made by the research community to address many of these challenges, and in this paper a consensus is presented on deficiencies in widely available MRS methodology and validated improvements that are currently in routine use at several clinical research institutions. In particular, the localization error for the PRESS localization sequence was found to be unacceptably high at 3 T, and use of the semi-adiabatic localization by adiabatic selective refocusing sequence is a recommended solution. Incorporation of simulated metabolite basis sets into analysis routines is recommended for reliably capturing the full spectral detail available from short TE acquisitions. In addition, the importance of achieving a highly homogenous static magnetic field (B0 ) in the acquisition region is emphasized, and the limitations of current methods and hardware are discussed. Most recommendations require only software improvements, greatly enhancing the capabilities of clinical MRS on existing hardware. Implementation of these recommendations should strengthen current clinical applications and advance progress toward developing and validating new MRS biomarkers for clinical use.
- Published
- 2019
4. Treatment Response Assessment in IDH-Mutant Glioma Patients by Noninvasive 3D Functional Spectroscopic Mapping of 2-Hydroxyglutarate
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Koch Institute for Integrative Cancer Research at MIT, Vander Heiden, Matthew G., Andronesi, O. C., Loebel, F., Bogner, W., Marjanska, M., Iafrate, A. J., Dietrich, J., Batchelor, T. T., Gerstner, E. R., Kaelin, W. G., Chi, A. S., Rosen, B. R., Cahill, D. P., Koch Institute for Integrative Cancer Research at MIT, Vander Heiden, Matthew G., Andronesi, O. C., Loebel, F., Bogner, W., Marjanska, M., Iafrate, A. J., Dietrich, J., Batchelor, T. T., Gerstner, E. R., Kaelin, W. G., Chi, A. S., Rosen, B. R., and Cahill, D. P.
- Abstract
Purpose: Measurements of objective response rates are critical to evaluate new glioma therapies. The hallmark metabolic alteration in gliomas with mutant isocitrate dehydrogenase (IDH) is the overproduction of oncometabolite 2-hydroxyglutarate (2HG), which plays a key role in malignant transformation. 2HG represents an ideal biomarker to probe treatment response in IDH-mutant glioma patients, and we hypothesized a decrease in 2HG levels would be measureable by in vivo magnetic resonance spectroscopy (MRS) as a result of antitumor therapy. Experimental Design: We report a prospective longitudinal imaging study performed in 25 IDH-mutant glioma patients receiving adjuvant radiation and chemotherapy. A newly developed 3D MRS imaging was used to noninvasively image 2HG. Paired Student t test was used to compare pre- and posttreatment tumor 2HG values. Test-retest measurements were performed to determine the threshold for 2HG functional spectroscopic maps (fSM). Univariate and multivariate regression were performed to correlate 2HG changes with Karnofsky performance score (KPS). Results: We found that mean 2HG (2HG/Cre) levels decreased significantly (median=48.1%; 95% confidence interval=27.3%-56.5%; P=0.007) in the posttreatment scan. The volume of decreased 2HG correlates (R2=0.88, P=0.002) with clinical status evaluated by KPS. Conclusions: We demonstrate that dynamic measurements of 2HG are feasible by 3D fSM, and the decrease of 2HG levels can monitor treatment response in patients with IDH-mutant gliomas. Our results indicate that quantitative in vivo 2HG imaging maybe used for precision medicine and early response assessment in clinical trials of therapies targeting IDH-mutant gliomas.
- Published
- 2018
5. P07.15 Diagnostic value of 2-hydroxyglutarate detection by 1H MR spectroscopy in patients with glioma and correlations with tumor phenotype and tissue dosage
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Di Stefano, A. L., primary, Branzoli, F., additional, Ottolenghi, C., additional, Capelle, L., additional, Mokhtari, K., additional, Villa, C. M., additional, Giry, M., additional, Marjanska, M., additional, Lehericy, S., additional, and Sanson, M., additional
- Published
- 2016
- Full Text
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6. In Vivo H Magnetic Resonance Spectroscopy in Young-Adult Daily Marijuana Users
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Muetzel, Ryan, Marjanska, M, Collins, PF, Becker, MP, Valabregue, R, Auerbach, EJ, Lim, KO, Luciana, M, and Child and Adolescent Psychiatry / Psychology
- Published
- 2013
7. Differences in apparent diffusion coefficients of brain metabolites between grey and white matter in the human brain measured at 7 T
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Kan, H.E., Techawiboonwong, A., Osch, M.J.P. van, Versluis, M.J., Deelchand, D.K., Henry, P.G., Marjanska, M., Buchem, M.A. van, Webb, A.G., and Ronen, I.
- Subjects
MRS ,PRESS ,DWS ,diffusion ,glutamate ,N-acetyl aspartyl glutamate - Published
- 2012
8. Functional NMR spectroscopy of the human brain at 7 T: an event-related study
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Mangia, S., Tkac, I., Gruetter, R., VAN DE MOORTELE, P. F., Marjanska, M., Bianciardi, M., DI SALLE, F., Garreffa, G., Maraviglia, Bruno, Ugurbil, K., and Giove, Federico
- Published
- 2005
9. O8.02 * MONITORING OF TREATMENT RESPONSE IN IDH-MUTANT GLIOMAS WITH IN-VIVO 3D MAGNETIC RESONANCE SPECTROSCOPY
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Cahill, D. P., primary, Loebel, F., additional, Bogner, W., additional, Marjanska, M., additional, Gerstner, E., additional, Batchelor, T., additional, Rosen, B. R., additional, Chi, A., additional, and Andronesi, O. C., additional
- Published
- 2014
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10. In vivo 13C NMR spectroscopy and metabolic modeling in the brain: a practical perspective
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Henry, P.-G., Adriany, G., Deelchand, D., Gruetter, R., Marjanska, M., Öz, G., Seaquist, E. R., Shestov, A., Uǧurbil, K., Henry, P.-G., Adriany, G., Deelchand, D., Gruetter, R., Marjanska, M., Öz, G., Seaquist, E. R., Shestov, A., and Uǧurbil, K.
- Abstract
In vivo 13C NMR spectroscopy has the unique capability to measure metabolic fluxes noninvasively in the brain. Quantitative measurements of metabolic fluxes require analysis of the 13C labeling time courses obtained experimentally with a metabolic model. The present work reviews the ingredients necessary for a dynamic metabolic modeling study, with particular emphasis on practical issues. © 2006 Elsevier Inc. All rights reserved.
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- 2012
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11. P5-13-05: Non-Invasive In Vivo 1H Magnetic Resonance Spectroscopy (MRS) Monitoring of Breast Tumor Response to IGF1R Targeted Therapy.
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Sachdev, D, primary, Lin, JE, additional, Lunzer, C, additional, Marjanska, M, additional, Garwood, M, additional, and Yee, D, additional
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- 2011
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12. PTMS51 The neurochemical profile of writer's cramp and its changes after non-invasive cortical stimulation:a 3 Tesla magnetic resonance spectroscopy study
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Meunier, S., primary, Marjanska, M., additional, Valabregue, R., additional, Traian, P., additional, Worbe, Y., additional, Russo, M., additional, Auerbach, E., additional, Grabli, D., additional, Bonnet, C., additional, Vidailhet, M., additional, and Lehericy, S., additional
- Published
- 2011
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13. Noninvasive Detection of Presymptomatic and Progressive Neurodegeneration in a Mouse Model of Spinocerebellar Ataxia Type 1
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Oz, G., primary, Nelson, C. D., additional, Koski, D. M., additional, Henry, P.-G., additional, Marjanska, M., additional, Deelchand, D. K., additional, Shanley, R., additional, Eberly, L. E., additional, Orr, H. T., additional, and Clark, H. B., additional
- Published
- 2010
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14. Spectroscopie IRM a 3T
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Galanaud, D., primary, Lehéricy, S., additional, Marjanska, M., additional, Vallabrègue, R., additional, Perlbarg, V., additional, and Chiras, J., additional
- Published
- 2008
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15. Highly specific determination of IDH status using edited in vivo magnetic resonance spectroscopy.
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Branzoli F, Di Stefano AL, Capelle L, Ottolenghi C, Valabrègue R, Deelchand DK, Bielle F, Villa C, Baussart B, Lehéricy S, Sanson M, and Marjanska M
- Subjects
- Adult, Brain Neoplasms genetics, Female, Follow-Up Studies, Glioma genetics, Humans, Male, Middle Aged, Prognosis, Prospective Studies, Young Adult, Biomarkers, Tumor genetics, Brain Neoplasms diagnosis, Glioma diagnosis, Isocitrate Dehydrogenase genetics, Magnetic Resonance Spectroscopy methods, Mutation
- Abstract
Background: Mutations in the isocitrate dehydrogenase (IDH) enzyme affect 40% of gliomas and represent a major diagnostic and prognostic marker. The goals of this study were to evaluate the performance of noninvasive magnetic resonance spectroscopy (MRS) methods to determine the IDH status of patients with brain gliomas through detection of the oncometabolite 2-hydroxyglutarate (2HG) and to compare performance of these methods with DNA sequencing and tissue 2HG analysis., Methods: Twenty-four subjects with suspected diagnosis of low-grade glioma were included prospectively in the study. For all subjects, MRS data were acquired at 3T using 2 MRS methods, edited MRS using Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS) sequence and a PRESS sequence optimized for 2HG detection, using a volume of interest larger than 6 mL. IDH mutational status was determined by a combination of automated immunohistochemical analysis and Sanger sequencing. Levels of 2HG in tissue samples measured by gas chromatography-mass spectrometry were compared with those estimated by MRS., Results: Edited MRS provided 100% specificity and 100% sensitivity in the detection of 2HG. The 2HG levels estimated by this technique were in line with those derived from tissue samples. Optimized PRESS provided lower performance, in agreement with previous findings., Conclusions: Our results suggest that edited MRS is one of the most reliable tools to predict IDH mutation noninvasively, showing high sensitivity and specificity for 2HG detection. Integrating edited MRS in clinical practice may be highly beneficial for noninvasive diagnosis of glioma, prognostic assessment, and treatment planning.
- Published
- 2018
- Full Text
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16. Relationship between transcranial magnetic stimulation measures of intracortical inhibition and spectroscopy measures of GABA and glutamate+glutamine.
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Tremblay S, Beaulé V, Proulx S, de Beaumont L, Marjanska M, Doyon J, Pascual-Leone A, Lassonde M, and Théoret H
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- Adult, Female, Humans, Magnetic Resonance Spectroscopy, Male, Motor Cortex chemistry, Transcranial Magnetic Stimulation, Glutamic Acid analysis, Glutamine analysis, Motor Cortex physiology, Neural Inhibition, gamma-Aminobutyric Acid analysis
- Abstract
Transcranial magnetic stimulation (TMS) can provide an index of intracortical excitability/inhibition balance. However, the neurochemical substrate of these measures remains unclear. Pharmacological studies suggest the involvement of GABAA and GABAB receptors in TMS protocols aimed at measuring intracortical inhibition, but this link remains inferential. Proton magnetic resonance spectroscopy ((1)H-MRS) permits measurement of GABA and glutamate + glutamine (Glx) concentrations in the human brain and might help in the direct empirical assessment of the relationship between TMS inhibitory measures and neurotransmitter concentrations. In the present study, MRS-derived relative concentrations of GABA and Glx measured in the left M1 of healthy participants were correlated with TMS measures of intracortical inhibition. Glx levels were found to correlate positively with TMS-induced silent period duration, whereas no correlation was found between GABA concentration and TMS measures. The present data demonstrate that specific TMS measures of intracortical inhibition are linked to shifts in cortical Glx, rather than GABA neurotransmitter levels. Glutamate might specifically interact with GABAB receptors, where higher MRS-derived Glx concentrations seem to be linked to higher levels of receptor activity.
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- 2013
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17. In vivo proton MRS to quantify anesthetic effects of pentobarbital on cerebral metabolism and brain activity in rat.
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Du F, Zhang Y, Iltis I, Marjanska M, Zhu XH, Henry PG, and Chen W
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- Adjuvants, Anesthesia administration & dosage, Animals, Male, Metabolic Clearance Rate drug effects, Protons, Rats, Rats, Sprague-Dawley, Brain drug effects, Brain physiology, Electroencephalography drug effects, Magnetic Resonance Spectroscopy methods, Neurotransmitter Agents analysis, Pentobarbital administration & dosage
- Abstract
To quantitatively investigate the effects of pentobarbital anesthesia on brain activity, brain metabolite concentrations and cerebral metabolic rate of glucose, in vivo proton MR spectra, and electroencephalography were measured in the rat brain with various doses of pentobarbital. The results show that (1) the resonances attributed to propylene glycol, a solvent in pentobarbital injection solution, can be robustly detected and quantified in the brain; (2) the concentration of most brain metabolites remained constant under the isoelectric state (silent electroencephalography) with a high dose of pentobarbital compared to mild isoflurane anesthesia condition, except for a reduction of 61% in the brain glucose level, which was associated with a 37% decrease in cerebral metabolic rate of glucose, suggesting a significant amount of "housekeeping" energy for maintaining brain cellular integrity under the isoelectric state; and (3) electroencephalography and cerebral metabolic activities were tightly coupled to the pentobarbital anesthesia depth and they can be indirectly quantified by the propylene glycol resonance signal at 1.13 ppm. This study indicates that in vivo proton MR spectroscopy can be used to measure changes in cerebral metabolite concentrations and cerebral metabolic rate of glucose under varied pentobarbital anesthesia states; moreover, the propylene glycol signal provides a sensitive biomarker for quantitatively monitoring these changes and anesthesia depth noninvasively., ((c) 2009 Wiley-Liss, Inc.)
- Published
- 2009
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18. Comparison of amyloid plaque contrast generated by T2-weighted, T2*-weighted, and susceptibility-weighted imaging methods in transgenic mouse models of Alzheimer's disease.
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Chamberlain R, Reyes D, Curran GL, Marjanska M, Wengenack TM, Poduslo JF, Garwood M, and Jack CR Jr
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- Amyloid beta-Peptides genetics, Animals, Humans, Image Enhancement methods, Mice, Mice, Transgenic, Reproducibility of Results, Sensitivity and Specificity, Algorithms, Alzheimer Disease diagnosis, Diffusion Magnetic Resonance Imaging methods, Disease Models, Animal, Image Interpretation, Computer-Assisted methods, Plaque, Amyloid pathology
- Abstract
One of the hallmark pathologies of Alzheimer's disease (AD) is amyloid plaque deposition. Plaques appear hypointense on T(2)-weighted and T(2)*-weighted MR images probably due to the presence of endogenous iron, but no quantitative comparison of various imaging techniques has been reported. We estimated the T(1), T(2), T(2)*, and proton density values of cortical plaques and normal cortical tissue and analyzed the plaque contrast generated by a collection of T(2)-weighted, T(2)*-weighted, and susceptibility-weighted imaging (SWI) methods in ex vivo transgenic mouse specimens. The proton density and T(1) values were similar for both cortical plaques and normal cortical tissue. The T(2) and T(2)* values were similar in cortical plaques, which indicates that the iron content of cortical plaques may not be as large as previously thought. Ex vivo plaque contrast was increased compared to a previously reported spin-echo sequence by summing multiple echoes and by performing SWI; however, gradient echo and SWI were found to be impractical for in vivo imaging due to susceptibility interface-related signal loss in the cortex., ((c) 2009 Wiley-Liss, Inc.)
- Published
- 2009
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19. Multinuclear NMR investigation of probe construction materials at 9.4T.
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Marjanska M, Waks M, Snyder CJ, and Vaughan JT
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- Magnetic Resonance Spectroscopy methods, Materials Testing, Reproducibility of Results, Sensitivity and Specificity, Specimen Handling methods, Magnetic Resonance Spectroscopy instrumentation, Magnetics instrumentation, Specimen Handling instrumentation, Transducers
- Abstract
This work investigates probe construction materials for their signal contribution to ultrashort echo time spectroscopy and imaging. (1)H, (13)C, and (31)P spectra were obtained at a field strength of 9.4 T for 16 materials considered for use in probe and holder design and construction. Four of the materials were found to be suited for the construction of NMR probes, housing of RF coils, and holders for in vivo experiments.
- Published
- 2008
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20. Editing through multiple bonds: threonine detection.
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Marjanska M, Henry PG, Uğurbil K, and Gruetter R
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- Animals, Humans, Hydrogen-Ion Concentration, Lactates metabolism, Male, Phantoms, Imaging, Rats, Rats, Sprague-Dawley, Reproducibility of Results, Brain metabolism, Magnetic Resonance Spectroscopy methods, Threonine metabolism
- Abstract
In in vivo (1)H spectroscopy, the signal at 1.32 ppm is usually assigned to lactate. This resonance position is shared with threonine at physiological pH. The similarity of spectral patterns of lactate and threonine renders the separate measurement of either threonine or lactate without and even with editing technically challenging. In this study, the threonine signal was detected using a single-shot multiple-bond editing technique and quantified in vivo in both rat and human brains. A threonine concentration was estimated at 0.8 +/- 0.3 mM (mean +/- SD, n = 6) in the rat brain and at approximately 0.33 mM in the human brain., ((c) 2008 Wiley-Liss, Inc.)
- Published
- 2008
- Full Text
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21. Proton echo-planar spectroscopic imaging of J-coupled resonances in human brain at 3 and 4 Tesla.
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Posse S, Otazo R, Caprihan A, Bustillo J, Chen H, Henry PG, Marjanska M, Gasparovic C, Zuo C, Magnotta V, Mueller B, Mullins P, Renshaw P, Ugurbil K, Lim KO, and Alger JR
- Subjects
- Adult, Female, Humans, Image Processing, Computer-Assisted, Male, Middle Aged, Sensitivity and Specificity, Signal Processing, Computer-Assisted, Brain Chemistry, Brain Mapping methods, Echo-Planar Imaging methods, Magnetic Resonance Spectroscopy methods
- Abstract
In this multicenter study, 2D spatial mapping of J-coupled resonances at 3T and 4T was performed using short-TE (15 ms) proton echo-planar spectroscopic imaging (PEPSI). Water-suppressed (WS) data were acquired in 8.5 min with 1-cm(3) spatial resolution from a supraventricular axial slice. Optimized outer volume suppression (OVS) enabled mapping in close proximity to peripheral scalp regions. Constrained spectral fitting in reference to a non-WS (NWS) scan was performed with LCModel using correction for relaxation attenuation and partial-volume effects. The concentrations of total choline (tCho), creatine + phosphocreatine (Cr+PCr), glutamate (Glu), glutamate + glutamine (Glu+Gln), myo-inositol (Ins), NAA, NAA+NAAG, and two macromolecular resonances at 0.9 and 2.0 ppm were mapped with mean Cramer-Rao lower bounds (CRLBs) between 6% and 18% and approximately 150-cm(3) sensitive volumes. Aspartate, GABA, glutamine (Gln), glutathione (GSH), phosphoethanolamine (PE), and macromolecules (MMs) at 1.2 ppm were also mapped, although with larger mean CRLBs between 30% and 44%. The CRLBs at 4T were 19% lower on average as compared to 3T, consistent with a higher signal-to-noise ratio (SNR) and increased spectral resolution. Metabolite concentrations were in the ranges reported in previous studies. Glu concentration was significantly higher in gray matter (GM) compared to white matter (WM), as anticipated. The short acquisition time makes this methodology suitable for clinical studies.
- Published
- 2007
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22. Determination of blood longitudinal relaxation time (T1) at high magnetic field strengths.
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Dobre MC, Uğurbil K, and Marjanska M
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- Animals, Blood Flow Velocity, Cattle, Hematocrit, Oxygen blood, Signal Processing, Computer-Assisted, Temperature, Blood Physiological Phenomena, Magnetic Resonance Imaging methods
- Abstract
In this study, a circulation system was used to measure T(1) values of bovine blood under physiological conditions at field strengths of 4.7, 7 and 9.4 T. Results show that T(1) increases linearly with magnetic field B(0) and can be described with the equation T(1)=129 ms/T B(0)+1167 ms for magnetic field strengths between 1.5 and 9.4 T.
- Published
- 2007
- Full Text
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23. Magnetic resonance imaging of Alzheimer's pathology in the brains of living transgenic mice: a new tool in Alzheimer's disease research.
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Jack CR Jr, Marjanska M, Wengenack TM, Reyes DA, Curran GL, Lin J, Preboske GM, Poduslo JF, and Garwood M
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- Alzheimer Disease genetics, Alzheimer Disease physiopathology, Amyloid beta-Peptides genetics, Amyloid beta-Peptides metabolism, Animals, Brain metabolism, Brain physiopathology, Humans, Magnetic Resonance Spectroscopy methods, Mice, Plaque, Amyloid genetics, Plaque, Amyloid metabolism, Plaque, Amyloid pathology, Radioisotopes, Alzheimer Disease pathology, Brain pathology, Disease Models, Animal, Magnetic Resonance Imaging methods, Mice, Transgenic
- Abstract
Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Cardinal pathologic features of AD are amyloid plaques and neurofibrillary tangles, and most in the field believe that the initiating events ultimately leading to clinical AD center on disordered metabolism of amyloid beta protein. Mouse models of AD have been created by inserting one or more human mutations associated with disordered amyloid metabolism and that cause early onset familial AD into the mouse genome. Human-like amyloid plaque formation increases dramatically with age in these transgenic mice. Amyloid reduction in humans is a major therapeutic objective, and AD transgenic mice allow controlled study of this biology. Recent work has shown that amyloid plaques as small as 35 microm can be detected using in vivo magnetic resonance microimaging (MRMI) at high magnetic field (9.4 T). In addition, age-dependent changes in metabolite concentration analogous to those that have been identified in human AD patients can be detected in these transgenic mice using single-voxel (1)H magnetic resonance spectroscopy ((1)H MRS) at high magnetic field. These MR-based techniques provide a new set of tools to the scientific community engaged in studying the biology of AD in transgenic models of the disease. For example, an obvious application is evaluating therapeutic modification of disease progression. Toward the end of this review, the authors include results from a pilot study demonstrating feasibility of using MRMI to detect therapeutic modification of plaque progression in AD transgenic mice.
- Published
- 2007
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24. Magnetic resonance imaging of Alzheimer's disease.
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Lehéricy S, Marjanska M, Mesrob L, Sarazin M, and Kinkingnehun S
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- Alzheimer Disease diagnostic imaging, Alzheimer Disease pathology, Atrophy diagnosis, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Spectroscopy, Neuropsychological Tests, Time Factors, Tomography, X-Ray Computed, Alzheimer Disease diagnosis, Brain pathology, Magnetic Resonance Imaging methods
- Abstract
A modern challenge for neuroimaging techniques is to contribute to the early diagnosis of neurodegenerative diseases, such as Alzheimer's disease (AD). Early diagnosis includes recognition of pre-demented conditions, such as mild cognitive impairment (MCI) or having a high risk of developing AD. The role of neuroimaging therefore extends beyond its traditional role of excluding other conditions such as neurosurgical lesions. In addition, early diagnosis would allow early treatment using currently available therapies or new therapies in the future. Structural imaging can detect and follow the time course of subtle brain atrophy as a surrogate marker for pathological processes. New MR techniques and image analysis software can detect subtle brain microstructural, perfusion or metabolic changes that provide new tools to study the pathological processes and detect pre-demented conditions. This review focuses on markers of macro- and microstructural, perfusion, diffusion and metabolic MR imaging and spectroscopy in AD.
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- 2007
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25. Detection of an antioxidant profile in the human brain in vivo via double editing with MEGA-PRESS.
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Terpstra M, Marjanska M, Henry PG, Tkác I, and Gruetter R
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- Adult, Female, Humans, Male, Tissue Distribution, Algorithms, Antioxidants metabolism, Ascorbic Acid metabolism, Glutathione metabolism, Magnetic Resonance Spectroscopy methods, Occipital Lobe metabolism
- Abstract
Vitamin C (ascorbate) and glutathione (GSH) are the two most concentrated non-enzymatic antioxidants in the human brain. Double editing with (DEW) MEGA-PRESS at 4T was designed in this study to measure both antioxidants in the same amount of time previously required to measure one. In the occipital lobe of four human subjects, resolved ascorbate (Asc) and GSH resonances were detected repeatedly and simultaneously using DEW MEGA-PRESS. The Asc and GSH concentrations measured using LCModel analysis of DEW MEGA-PRESS spectra were 0.8 +/- 0.1 and 1.0 +/- 0.1 micromol/g (mean +/- SD), with average Cramer-Rao lower bounds (CRLB) of 10% and 7%, respectively. Aside from the effects of J-modulation at a common echo time (TE), double editing did not compromise sensitivity. To determine the extent to which the oxidized forms of Asc and GSH contribute to DEW MEGA-PRESS spectra in vivo, chemical shifts and coupling constants for dehydroascorbate (DHA) and oxidized glutathione (GSSG) were measured at physiologic pH and temperature. DHA does not contribute to the 3.73 ppm DEW MEGA-PRESS Asc resonance. GSSG contributions to the DEW MEGA-PRESS GSH resonance (3.0 ppm) are negligible under physiologic conditions, and would be evidenced by a distinct GSSG resonance (3.3 ppm) at exceptionally high concentrations.
- Published
- 2006
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26. In vivo 13C NMR spectroscopy and metabolic modeling in the brain: a practical perspective.
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Henry PG, Adriany G, Deelchand D, Gruetter R, Marjanska M, Oz G, Seaquist ER, Shestov A, and Uğurbil K
- Subjects
- Animals, Carbon Radioisotopes, Models, Biological, Rats, Brain metabolism, Magnetic Resonance Spectroscopy
- Abstract
In vivo 13C NMR spectroscopy has the unique capability to measure metabolic fluxes noninvasively in the brain. Quantitative measurements of metabolic fluxes require analysis of the 13C labeling time courses obtained experimentally with a metabolic model. The present work reviews the ingredients necessary for a dynamic metabolic modeling study, with particular emphasis on practical issues.
- Published
- 2006
- Full Text
- View/download PDF
27. Proton-observed carbon-edited NMR spectroscopy in strongly coupled second-order spin systems.
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Henry PG, Marjanska M, Walls JD, Valette J, Gruetter R, and Ugurbil K
- Subjects
- Carbon Isotopes, Computer Simulation, Protons, Sensitivity and Specificity, Glutamic Acid chemistry, Magnetic Resonance Spectroscopy methods
- Abstract
Proton-observed carbon-edited (POCE) NMR spectroscopy is commonly used to measure 13C labeling with higher sensitivity compared to direct 13C NMR spectroscopy, at the expense of spectral resolution. For weakly coupled first-order spin systems, the multiplet signal at a specific proton chemical shift in POCE spectra directly reflects 13C enrichment of the carbon attached to this proton. The present study demonstrates that this is not necessarily the case for strongly coupled second-order spin systems. In such cases NMR signals can be detected in the POCE spectra even at chemical shifts corresponding to protons bound to 12C. This effect is demonstrated theoretically with density matrix calculations and simulations, and experimentally with measured POCE spectra of [3-13C]glutamate., (Copyright 2006 Wiley-Liss, Inc.)
- Published
- 2006
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28. NMR studies of chloroform@cryptophane-A and chloroform@bis-cryptophane inclusion complexes oriented in thermotropic liquid crystals.
- Author
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Chaffee KE, Marjanska M, and Goodson BM
- Subjects
- Binding Sites, Carbon Radioisotopes, Macromolecular Substances analysis, Macromolecular Substances chemistry, Materials Testing, Molecular Conformation, Phase Transition, Temperature, Chloroform analysis, Chloroform chemistry, Crystallography methods, Liquid Crystals analysis, Liquid Crystals chemistry, Magnetic Resonance Spectroscopy methods
- Abstract
Oriented inclusion complexes of chloroform@cryptophane-A and chloroform@bis-cryptophane were prepared using a nematic thermotropic liquid crystal (ZLI 1132), and the alignment and magnetic resonance properties of these host-guest systems were studied via (13)C NMR of the labeled guests. Large (1)H-(13)C dipolar splittings for (13)CHCl(3) guests indicated significantly enhanced (approximately 2-fold) ordering for the trapped vs. free ligands under all conditions studied, with similar ordering observed for the two complexes-despite significant differences in size and motional freedom between the hosts. For each environment, variable-temperature studies permitted the sign and magnitude of the order parameter for chloroform's C-H bond to be independently determined from the (13)C chemical shift anisotropy (CSA) shifts (via the gradient method) and the restored (1)H-(13)C dipolar couplings. In both systems, the results are consistent with overall alignment of the complexes such that the cage principal axis lies roughly perpendicular to the LC director.
- Published
- 2006
- Full Text
- View/download PDF
29. Monitoring disease progression in transgenic mouse models of Alzheimer's disease with proton magnetic resonance spectroscopy.
- Author
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Marjanska M, Curran GL, Wengenack TM, Henry PG, Bliss RL, Poduslo JF, Jack CR Jr, Ugurbil K, and Garwood M
- Subjects
- Animals, Disease Progression, Female, Magnetic Resonance Spectroscopy, Male, Mice, Mice, Transgenic, Protons, Alzheimer Disease genetics, Alzheimer Disease pathology, Disease Models, Animal
- Abstract
Currently no definitive biomarker of Alzheimer's disease (AD) is available, and this impedes both clinical diagnosis in humans and drug discovery in transgenic animal models. Proton magnetic resonance spectroscopy ((1)H MRS) provides a noninvasive way to investigate in vivo neurochemical abnormalities. Each observable metabolite can potentially provide information about unique in vivo pathological processes at the molecular or cellular level. In this study, the age-dependent 1H MRS profile of transgenic AD mice was compared to that of wild-type mice. Twenty-seven APP-PS1 mice (which coexpress mutated human presenilin 1 and amyloid-beta precursor protein) and 30 wild-type mice age 66-904 days were examined, some repeatedly. A reduction in the levels of N-acetylaspartate and glutamate, compared with total creatine levels, was found in APP-PS1 mice with advancing age. The most striking finding was a dramatic increase in the concentration of myo-inositol with age in APP-PS1 mice, which was not observed in wild-type mice. The age-dependent neurochemical changes observed in APP-PS1 mice agree with results obtained from in vivo human MRS studies. Among the different transgenic mouse models of AD that have been studied with 1H MRS, APP-PS1 mice seem to best match the neurochemical profile exhibited in human AD. 1H MRS could serve as a sensitive in vivo surrogate indicator of therapeutic efficacy in trials of agents designed to reduce neurotoxicity due to microglial activation. Because of its noninvasive and repeatable nature, MRS in transgenic models of AD could substantially accelerate drug discovery for this disease.
- Published
- 2005
- Full Text
- View/download PDF
30. Sequence design for magnetic resonance spectroscopic imaging of prostate cancer at 3 T.
- Author
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Cunningham CH, Vigneron DB, Marjanska M, Chen AP, Xu D, Hurd RE, Kurhanewicz J, Garwood M, and Pauly JM
- Subjects
- Humans, Male, Middle Aged, Phantoms, Imaging, Choline metabolism, Citrates metabolism, Magnetic Resonance Spectroscopy methods, Prostatic Neoplasms metabolism
- Abstract
Magnetic resonance spectroscopic imaging (MRSI) has proven to be a powerful tool for the metabolic characterization of prostate cancer in patients before and following therapy. The metabolites that are of particular interest are citrate and choline because an increased choline-to-citrate ratio can be used as a marker for cancer. High-field systems offer the advantage of improved spectral resolution as well as increased magnetization. Initial attempts at extending MRSI methods to 3 T have been confounded by the J-modulation of the citrate resonances. A new pulse sequence is presented that controls the J-modulation of citrate at 3 T such that citrate is upright, with high amplitude, at a practical echo time. The design of short (14 ms) spectral-spatial refocusing pulses and trains of nonselective refocusing pulses are described. Phantom studies and simulations showed that upright citrate with negligible sidebands is observed at an echo time of 85 ms. Studies in a human subject verified that this behavior is reproduced in vivo and demonstrated that the water and lipid suppression of the new pulse sequence are sufficient for application in prostate cancer patients., (Copyright 2005 Wiley-Liss, Inc.)
- Published
- 2005
- Full Text
- View/download PDF
31. Uncovering hidden in vivo resonances using editing based on localized TOCSY.
- Author
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Marjanska M, Henry PG, Bolan PJ, Vaughan B, Seaquist ER, Gruetter R, Uğurbil K, and Garwood M
- Subjects
- Animals, Brain Chemistry, Humans, Male, Phantoms, Imaging, Rats, Rats, Sprague-Dawley, Signal Processing, Computer-Assisted, Brain metabolism, Glucose metabolism, Lactic Acid metabolism, Magnetic Resonance Spectroscopy methods
- Abstract
A novel single-shot spectral editing technique for in vivo proton NMR is proposed to recover resonances of low-concentration metabolites obscured by very strong resonances. With this new method, editing is performed by transferring transverse magnetization to J-coupled spins from selected coupling partners using a homonuclear Hartmann-Hahn polarization transfer with adiabatic pulses. The current implementation uses 1D-TOCSY with single-voxel localization based on LASER to recover the H1 proton of beta-glucose at 4.63 ppm from under water and the lactate methyl resonances from beneath a strong lipid signal. The method can be extended to further spin systems where conventional editing methods are difficult to perform., (Copyright 2005 Wiley-Liss, Inc.)
- Published
- 2005
- Full Text
- View/download PDF
32. Isotropic-liquid crystalline phase diagram of a CdSe nanorod solution.
- Author
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Li LS, Marjanska M, Park GH, Pines A, and Alivisatos AP
- Abstract
We report the isotropic-liquid crystalline phase diagram of 3.0 nm x 60 nm CdSe nanorods dispersed in anhydrous cyclohexane. The coexistence concentrations of both phases are found to be lower and the biphasic region wider than the results predicted by the hard rod model, indicating that the attractive interaction between the nanorods may be important in the formation of the liquid crystalline phase in this system.
- Published
- 2004
- Full Text
- View/download PDF
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