Abstract:
:We have obtained high-field (11.7 Tesla), high-resolution carbon-13 solid-state "magic-angle" sample-spinning nuclear magnetic resonance (NMR) spectra of a variety of phospholipids, sphingolipids, myelin and white matter samples, resolving and assigning over 40 resonances in the spectra of human and bovine myelin. The NMR results indicated no large spectral changes due to sample preparation, sample freezing, or brain location, and also no changes in myelin structure detectable via light microscopy, electron microscopy, thin layer chromatography, or sodium dodecyl sulfate-polyacrylamide gel electrophoresis, attributable to the sometimes lengthy NMR data acquisition process. Human myelin and white matter chemical shift assignments were made based on 13C "magic angle" sample spinning (MAS) NMR spectra of individual model lipids, as well as on spectra of lipid mixtures. In all myelin samples there were essentially no features attributable to membrane proteins, with the exception of one small feature due to C zeta of Arg residues, primarily in the myelin basic proteins. The general similarity between the model lipid and intact myelin spectra suggested no major effects of protein on lipid mobility. We have also investigated human myelin samples as a function of developmental age (4, 15, 48 months and adult), and our results showed only small changes in overall lipid composition, although there were significant decreases in lipid hydrocarbon chain unsaturation with age, as determined by computer line-shape simulations of myelin and model compounds. The spectrum of an infant leukoencephalopathy myelin showed marked decreases in galactocerebrosides. Overall, the ability to resolve and assign over 40 resonances in the 13C MAS NMR spectra of myelin, and to detect changes as a function of development and disease, should provide a useful starting point for further more detailed studies of myelin membrane molecular motions, and function.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Husted C,Montez B,Le C,Moscarello MA,Oldfield Edoi
10.1002/mrm.1910290204subject
Has Abstractpub_date
1993-02-01 00:00:00pages
168-78issue
2eissn
0740-3194issn
1522-2594journal_volume
29pub_type
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.25455
更新日期:2015-09-01 00:00:00
abstract::A method is presented for the detection of quadrupole splitting in tissue, where the spectral line splittings are typically unobservable. The method used is a study of the rate of rotation of the flip angle as a function of radiofrequency (rf) amplitude. Our results with samples of skeletal muscle and cat brain indica...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:2018-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2011-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2018-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1992-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1990-09-01 00:00:00
abstract::Excitation by conventional B1 pulses in surface coil chemical-shift imaging experiments yields resonance intensities that vary greatly with position. B1-compensated semi-selective pulses overcome much of this problem. These pulses are employed for excitation and refocusing in 1H NMR spectroscopic localization in the i...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910250118
更新日期:1992-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.25133
更新日期:2015-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910310218
更新日期:1994-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2019-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.22779
更新日期:2011-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1986-12-01 00:00:00
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doi:10.1002/mrm.27927
更新日期:2020-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2006-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1999-10-01 00:00:00
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更新日期:2014-12-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1989-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:1998-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:1990-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2013-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2015-11-01 00:00:00
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更新日期:2012-12-01 00:00:00
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更新日期:2015-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1993-10-01 00:00:00