다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

https://www.cell.com/cell-metabolism/pdf/S1550-4131(11)00420-7.pdf

Brain energy metabolism: focus on astrocyte-neuron metabolic cooperation

Proton NMR chemical shift and J-coupling values are presented for 35 metabolites that can be detected by in vivo or in vitro NMR studies of mammalian brain. Measurements were obtained using high-field NMR spectra of metabolites in solution, under conditions typical for normal physiological temperature and pH. This information is presented with an accuracy that is suitable for computer simulation of metabolite spectra to be used as basis functions of a parametric spectral analysis procedure. This procedure is verified by the analysis of a rat brain extract spectrum, using the measured spectral parameters. In addition, the metabolite structures and example spectra are presented, and clinical applications and MR spectroscopic measurements of these metabolites are reviewed.

http://pfeifer.phas.ubc.ca/refbase/files/Govindaraju-NMRBiomed-2000-13-129.pdf

Proton NMR chemical shifts and coupling constants for brain metabolites.

Functional brain imaging with positron emission tomography and magnetic resonance imaging has been used extensively to map regional changes in brain activity. The signal used by both techniques is based on changes in local circulation and metabolism (brain work). Our understanding of the cell biology of these changes has progressed greatly in the past decade. New insights have emerged on the role of astrocytes in signal transduction as has an appreciation of the unique contribution of aerobic glycolysis to brain energy metabolism. Likewise our understanding of the neurophysiologic processes responsible for imaging signals has progressed from an assumption that spiking activity (output) of neurons is most relevant to one focused on their input. Finally, neuroimaging, with its unique metabolic perspective, has alerted us to the ongoing and costly intrinsic activity within brain systems that most likely represents the largest fraction of the brain's functional activity.

Brain Work and Brain Imaging

Continuing improvements in analytical technology along with an increased interest in performing comprehensive, quantitative metabolic profiling, is leading to increased interest pressures within the metabolomics community to develop centralized metabolite reference resources for certain clinically important biofluids, such as cerebrospinal fluid, urine and blood. As part of an ongoing effort to systematically characterize the human metabolome through the Human Metabolome Project, we have undertaken the task of characterizing the human serum metabolome. In doing so, we have combined targeted and non-targeted NMR, GC-MS and LC-MS methods with computer-aided literature mining to identify and quantify a comprehensive, if not absolutely complete, set of metabolites commonly detected and quantified (with today's technology) in the human serum metabolome. Our use of multiple metabolomics platforms and technologies allowed us to substantially enhance the level of metabolome coverage while critically assessing the relative strengths and weaknesses of these platforms or technologies. Tables containing the complete set of 4229 confirmed and highly probable human serum compounds, their concentrations, related literature references and links to their known disease associations are freely available at http://www.serummetabolome.ca.

/pdf/the-human-serum-metabolome-52a86bwnf3.pdf

The Human Serum Metabolome

Corrigendum to “A comparison of 13C NMR measurements of the rates of glutamine synthesis and the tricarboxylic acid cycle during oral and intravenous administration of [1-13C]glucose”: [Brain Research Protocols, 10 (2003) 181–190]☆

Objective
The aim of this study is to present a new approach for making quantitative single-voxel T2 measurements from an arbitrarily shaped region of interest (ROI), where the advantage of the signal-to-noise ratio (SNR) per unit time of the single-voxel approach over conventional imaging approach can be achieved.

/pdf/quantitative-t2-measurement-of-a-single-voxel-with-arbitrary-38bwk17q64.pdf

Quantitative T2 measurement of a single voxel with arbitrary shape using pinwheel excitation and CPMG acquisition

PURPOSE Accumulation of triglycerides in nonadipose tissue (e.g. ectopic lipids) is characteristic of metabolic derangements and is linked to insulin resistance and cardiovascular disease. Although the detrimental effects of the total amount of ectopic fat has been established, the role of composition of the ectopic lipid stores is unknown. In this study we used proton magnetic resonance spectroscopy (1 H-MRS) homonuclear spectral editing to characterize lipid stores in adipose tissue and skeletal muscle at 4 T. METHODS A MEGA-sLASER sequence was used to selectively detect lipid resonances that are scalar coupled to the methine resonance at 5.31 ppm and that can be used to estimate saturated fatty acid and mono- and polyunsaturated fatty acids. Phantom experiments were performed to empirically determine correction factors for editing efficiency of the different lipid groups. RESULTS The spectral editing approach enabled the estimation of saturated, mono-unsaturated, and polyunsaturated fatty acid contributions in phantoms and in vivo. These estimations are in the same order as reported in studies using invasive biopsies. CONCLUSIONS In this study, we have shown the feasibility of spectral editing techniques for ectopic lipid store characterization with 1 H-MRS, regardless of spectral resolution (e.g., B0- field strength). This new approach offers the opportunity to study ectopic lipid composition in relation to metabolic diseases. Magn Reson Med 79:619-627, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Measurement of lipid composition in human skeletal muscle and adipose tissue with 1 H-MRS homonuclear spectral editing.

Proton MR spectroscopy can detect a detailed metabolic profile of the human brain noninvasively. Despite the wide range of metabolites that can be detected, spectral overlap of resonances from different compounds is routinely observed. Primary examples are the overlap of GABA and creatine, glutamate and glutamine, and lactate and lipids. In the case of partial spectral overlap, the compounds may be separated through a spectral fitting routine and go to a higher magnetic field strength. However, in the case of complete spectral overlap, the use of spectral editing or 2D NMR is mandatory. On relatively stable organs like the brain or muscle, the use of J-difference spectral editing is most straightforward and can provide consistent and reliable results.

Spectral Editing and 2D NMR

This chapter gives a brief overview of the principles of 1H NMR spectroscopy when applied to study metabolism in vivo. The basic methodology of in vivo 1H NMR, such as spatial localization, shimming and water suppression is described. Special attention is given to spectral quantification. The problem of spectral overlap of resonances is addressed through the use of spectral editing methods.

Robin A. de Graaf

Papers

Corrigendum to “A comparison of 13C NMR measurements of the rates of glutamine synthesis and the tricarboxylic acid cycle during oral and intravenous administration of [1-13C]glucose”: [Brain Research Protocols, 10 (2003) 181–190]☆

Quantitative T2 measurement of a single voxel with arbitrary shape using pinwheel excitation and CPMG acquisition

Measurement of lipid composition in human skeletal muscle and adipose tissue with 1 H-MRS homonuclear spectral editing.

Spectral Editing and 2D NMR

Principles of 1 H NMR Spectroscopy In Vivo