Despite obvious improvements in spectral resolution at high magnetic field, the detection of 13C labeling by 1H-[13C] NMR spectroscopy remains hampered by spectral overlap, such as in the spectral region of 1H resonances bound to C3 of glutamate (Glu) and glutamine (Gln), and C6 of N-acetylaspartate (NAA). The aim of this study was to develop, implement, and apply a novel 1H-[13C] NMR spectrosc...

Dynamic nuclear polarization has enabled hyperpolarization of nuclei such as 13C and 15N in endogenous substances. The resulting high nuclear polarization makes it possible to perform subsecond 13C MRI. By using the dynamic nuclear polarization hyperpolarization technique, 10% polarization was obtained in an aqueous solution of 100 mM 13C-labeled urea, ready for injection. The in vivo T1 relaxa...

Rigorous mathematical modeling of carbon-labeling experiments allows estimation of fluxes through the pathways of central carbon metabolism, yielding powerful information for basic scientific studies as well as for a wide range of applications. However, the mathematical models that have been developed for flux determination from 13C labeling data have commonly neglected the influence of kinetic...

The objective of this study was to determine whether differential labeling of 13C occurs in pigs fed diets with different 13C abundances and, if so, to use 13C as a label to determine true amino acid digestibility. Forty-eight pigs averaging 10.5 kg BW were fed dietary treatments consisting of a corn-corn gluten meal-crystalline amino acid diet (C-CGM) and a wheat-soybean meal diet (W-SBM). The...

Abstract. We demonstrate room-temperature 13C hyperpolarization by dynamic nuclear polarization (DNP) using optically polarized triplet electron spins in two polycrystalline systems: pentacene-doped [carboxyl-13C] benzoic acid and microdiamonds containing nitrogen-vacancy (NV−) centers. For both samples, the integrated solid effect (ISE) is used to polarize spin system magnetic fields of 350–40...

Through-bond and through-space solid-state NMR correlation experiments at natural isotopic abundance (refocused cross-polarization incredible natural abundance double quantum transfer experiment (CPINADEQUATE), 1H-13C HETCOR, 1H-13C magic-angle spinning J heteronuclear multiple-quantum coherence (MAS-J-HMQC)) are presented on a moderately sized molecule of simavastatin (C25H38O5). Refocused 13C...

Recently, a quantitative J correlation technique has been presented that permits measurement of 3Jc'c' in proteins isotopically enriched with 13C [Hu, J.-S. and Bax, A. (1996) J. Am. Chem. Soc., 118, 8170-8171]. Here, we describe an analogous experiment that is less sensitive to transverse 13C' relaxation, which is the principal limiting factor in all 13C-13C long-range correlation experiments ...

Various motionally averaged 31P-1H, 13C-1H, 1H-1H, and 31P-13C dipolar couplings were measured for natural-abundance and unoriented phosphocholine in the L alpha phase. The couplings were obtained and assigned by a variety of advanced and partly novel two-dimensional solid-state NMR experiments. Whereas 31P-1H and 31P-13C dipolar couplings provide long-range structural constraints, geminal 1H-1...

Magnetic resonance spectroscopic imaging has been used to follow glutathione metabolism and evaluate glutathione heterogeneity in intact tumor tissue. Stable isotope-labeled glutathione was detected in s.c. implanted fibrosarcoma tumors in anesthetized rats following infusion of [2-13C]glycine. Using 1H-decoupled 13C magnetic resonance spectroscopy, the appearance of [2-13C]glycine at 42.4 ppm ...

Abstract Oxaloacetate (OAA) inhibits the Warburg effect by reducing glucose-derived lactate levels in human cancer cell lines. In dose ranging IC50 experiments with hepatocellular carcinoma (HCC) lines, OAA inhibited growth concentration range 1.7 - 2.4 mM. Previously, we showed that presence of OAA, [U-13C]glucose derived was reduced 48.8% GBM cells. also increased survival mouse models GBM. H...