Abstract:
:The previously observed improvement in spectral resolution of tissue proton NMR with high-resolution magic angle spinning (HRMAS) was speculated to be due largely to freeze-thawing artifacts resulting from tissue storage. In this study, 12 human prostate samples were analyzed on a 14.1T spectrometer at 3 degrees C, with HRMAS rates of 600 and 700 Hz. These samples were measured fresh and after they were frozen for 12-16 hr prior to thawing. The spectral linewidths measured from fresh and previously frozen samples were identical for all metabolites except citrate and acetate. The metabolite intensities of fresh and freeze-thawed samples depend on the quantification procedures used; however, in this experiment the differences of means were <30%. As expected, it was found that tissue storage impacts tissue quality for pathological analysis, and HRMAS conditions alone are not sufficiently destructive to impair pathological evaluation. Furthermore, although storage conditions affect absolute metabolite concentrations in NMR analysis, relative metabolite concentrations are less affected.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Wu CL,Taylor JL,He W,Zepeda AG,Halpern EF,Bielecki A,Gonzalez RG,Cheng LLdoi
10.1002/mrm.10645subject
Has Abstractpub_date
2003-12-01 00:00:00pages
1307-11issue
6eissn
0740-3194issn
1522-2594journal_volume
50pub_type
杂志文章abstract::Due to the presence of gross magnetic susceptibility artifacts, functional MRI (fMRI) has proved problematic in studies of the human inferior frontal cortex (IFC). There is a strong desire, therefore, to employ techniques that mitigate susceptibility artifacts in the IFC while preserving the imaging parameters of an f...
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