13 C-bonded protons of glutamate. To take full advantage of the simultaneous detection of 12 C-and 13 Cbonded protons, we implemented a quantitation procedure to properly measure both glutamate C4 and C3 enrichments. This procedure relies on LCModel analysis with a basis set to account for simultaneous signal changes of protons bound to 12 C and 13 C. Signal changes were mainly attributed to 12 C-and 13 C-bonded protons of glutamate. As a result, we were able to measure the tricarboxylic acid (TCA) cycle flux in a 3.9 cm 3 voxel centered in the monkey brain on a whole-body 3 Tesla system (V TCA ‫؍‬ 0.55 ؎ 0.04 mol.g ؊1 .min ؊1 , N ‫؍‬ 4). This work demonstrates that oxidative metabolism can be quantified in deep structures of the brain on clinical MRI systems, without the need for a 13 NMR studies of metabolism with the use of 13 C-labeled glucose have considerably evolved over the past 25 years, following pioneer work on cell suspensions (1,2). Since the sensitivity of 13 C spectroscopy is intrinsically low, investigators performed the first in vivo brain studies using indirect { 13 C}-1 H detection of amino-acid labeling, to take advantage of the higher sensitivity of 1 H (3,4). Because of the overwhelming signal of 12 C-bonded protons, and the strong peak overlapping on 1 H spectra, 13 C-coupled protons of glutamate (Glu) have been detected with the use of such editing techniques as POCE (3). This approach has been implemented successfully in several research units, leading to in vivo localized measurements of brain metabolic fluxes, such as the TCA cycle flux V TCA (5-10). However, heteronuclear editing techniques require the use of both 1 H and 13 C radiofrequency (RF) transmitters and coils, as well as appropriate pulse sequences that are not implemented on most clinical MR systems. RF decoupling associated with heteronuclear editing is also problematic in human studies, due to power deposition to the tissue (11). Moreover, POCE-like sequences only detect the increase in 13 C-coupled protons during the course of 13 C enrichment. They ignore the corresponding decrease in 12 C-bonded protons, and thus miss half of the available information. Since the mid 1980s, when the early POCE measurements were obtained, hardware improvements have led to higher spectrum quality and stability; thus, the requirement for editing techniques is now questionable.In this context, our first objective was to demonstrate that 13 C incorporation into glutamate inside deep structures of the monkey brain could be detected with the sensitivity of 1 H without editing, using a 1 H point-resolved spectroscopy (PRESS) sequence on a whole-body 3 Tesla system. Our second objective was to propose a 13 C quantitation procedure based on LCModel analysis (12), which takes full advantage of the simultaneous detection of the decrease in 12 C-bonded protons of glutamate and the increase in 13 C-coupled satellites. V TCA was assessed after it was converted into glutamate 13 C4 and 13 C3 fractional enrichments (FEs). The results demonstrate that on...

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We demonstrated that choosing an LMA Supreme was an efficient pharyngolaryngeal morbidity-sparing strategy. Moreover, we showed that the LMA Supreme and the ETT were equally effective airways for a routine gynecological laparoscopy procedure.

We demonstrated that LaT, EMGp, and ALA of the swallowing reflex were influenced by tracheostomy tube CP. The swallowing reflex was progressively more difficult to elicit with increasing CP and when activated, the resulting motor swallowing activity and efficiency at elevating the larynx were depressed.