Significance Hyperpolarization is a significant development in MRI because it allows for imaging different metabolites real time vivo. There are no fundamental obstacles to rapid translation of this technique. Yet, date, has been necessary use persistent radicals that need be filtered out before injection and require pharmacological tests, which slow down the overall protocol, leading reduced sensitivity. The demonstration possible prepare purely endogenous agents probe metabolism vivo...

Vitamin C for longer lifetimes: N-oxide radicals that are widely used dynamic nuclear polarization can be reduced by scavengers such as sodium ascorbate (vitamin C) during the dissolution process, thus diminishing losses of transfer and extending transverse longitudinal relaxation times in NMR spectroscopy (see picture). Detailed facts importance to specialist readers published "Supporting Information". Such documents peer-reviewed, but not copy-edited or typeset. They made available...

An important development in the field of NMR spectroscopy has been advent hyperpolarization approaches, capable yielding nuclear spin states whose value exceeds by orders-of-magnitude what even highest-field spectrometers can afford under Boltzmann equilibrium. Included among these methods is an ex situ dynamic polarization (DNP) approach, which yields liquid-phase samples possessing polarizations up to 50 %. Although providing sensitivity equivalent averaging about 1 000 scans, this...

The Krebs (or tricarboxylic acid (TCA)) cycle has a central role in the regulation of brain energy and metabolism, yet TCA intermediates have never been directly detected vivo. This study reports first direct vivo observation intermediate intact brain, namely, 2-oxoglutarate, key biomolecule connecting metabolism to neuronal activity. Our reveals important information about biochemical processes hitherto considered undetectable. In particular, it provides evidence that transport across inner...

Multidimensional acquisitions play a central role in the progress and applications of nuclear magnetic resonance (NMR) spectroscopy. Such experiments have been collected traditionally as an array one-dimensional scans, with suitably incremented delay parameters that encode along independent temporal domains nD spectral distribution being sought. During past few years, ultrafast approach to NMR has introduced is capable delivering any type multidimensional spectrum single transient. This...

Hyperpolarized magnetic resonance via dissolution dynamic nuclear polarization necessitates the transfer of hyperpolarized molecules from polarizer to imager prior in vivo measurements. This process leads unavoidable losses polarization, which are difficult evaluate once solution has been injected into an animal. We propose a method measure inside bore, 3 s following dissolution, at time injection, using precise quantification infusate concentration. situ allows for distinguishing between...

The mammalian brain relies primarily on glucose as a fuel to meet its high metabolic demand. Among the various techniques used study cerebral metabolism, 13C magnetic resonance spectroscopy (MRS) allows following fate of 13C-enriched substrates through pathways. We herein demonstrate that it is possible measure metabolism in vivo with sub-second time resolution using hyperpolarized MRS. In particular, dynamic 13C-labeling pyruvate and lactate formed from 13C-glucose was observed real time....

An approach enabling the acquisition of 2D nuclear magnetic resonance (NMR) spectra within a single scan has been recently proposed. A promising application opened up by this "ultrafast" data format concerns monitoring chemical transformations as they happen, in real time. The present paper illustrates some potential with two examples: (i) following an H/D exchange process that occurs upon dissolving protonated protein D2O, and (ii) real-time situ tracking transient Meisenheimer complex...

The dynamics of l-lactate transport across the blood-brain barrier (BBB) and its cerebral metabolism are still subject to debate. We studied lactate uptake intracellular in mouse brain using hyperpolarized 13C magnetic resonance spectroscopy (MRS). Following intravenous injection [1-13C]lactate, we observed that distribution label between pyruvate, which has been shown be representative their pool size ratio, is different NMRI C57BL/6 mice, latter exhibiting a higher level dehydrogenase A (...

Abstract Cerebral metabolism, which can be monitored by magnetic resonance spectroscopy (MRS), changes rapidly after brain ischaemic injury. Hyperpolarisation techniques boost 13 C MRS sensitivity several orders of magnitude, thereby enabling in vivo monitoring biochemical transformations hyperpolarised (HP) C-labelled precursors with a time resolution seconds. The exogenous administration the metabolite L-lactate was shown to decrease lesion size and ameliorate neurological outcome...

We present a method that implements directional, perfect state transfers within branched spin network by exploiting quantum interferences in the time domain. This provides tool for isolating subsystems from large and complex one. Directionality is achieved interrupting spin-spin coupled evolution with periods of free Zeeman evolutions, whose timing tuned to be commensurate relative phases accrued specific pairs. leads resonant transfer between chosen qubits detuning all remaining pathways...

Abstract In vivo localized and fully adiabatic homonuclear heteronuclear polarization transfer experiments were designed performed in the rat brain at 9.4 T after infusion of hyperpolarized sodium [1,2‐ 13 C 2 ] [1‐ C] acetate. The method presented herein leads to highly enhanced detection short‐ 1 as well attached protons. This indirect scheme allows for probing additional molecular sites substrates their metabolites can thus lead improved spectral resolution such case C‐acetate metabolism....

Dissolution dynamic nuclear polarization (DNP) provides a way to tremendously improve the sensitivity of magnetic resonance experiments. Once spins are hyperpolarized by dissolution DNP, radicals used as polarizing agents become undesirable since their presence is an additional source spin relaxation and toxicity might be issue. This study demonstrates feasibility preparing [1‐ 13 C]2‐methylpropan‐2‐ol ( tert ‐butanol) solution free persistent using spin‐labeled thermoresponsive hydrophilic...

The metabolic shift induced in human CD4+ T lymphocytes by stimulation is characterized an upregulation of glycolysis, leading to augmentation lactate production. This adaptation has already been highlighted with various techniques and reported several previous studies. We herein propose a method rapidly noninvasively detect the associated increase flux from pyruvate catalyzed dehydrogenase using hyperpolarized 13C magnetic resonance, technique which can be used for vivo imaging. It was...

Abstract Glioblastoma (GBM) is the most aggressive brain tumor type in adults. GBM heterogeneous, with a compact core lesion surrounded by an invasive front. This front highly relevant for recurrence but generally non-detectable using standard imaging techniques. Recent studies demonstrated distinct metabolic profiles of phenotype GBM. Magnetic resonance (MR) hyperpolarized 13 C-labeled probes rapidly advancing field that provides real-time information. Here, we applied C-glucose MR to mouse...

Hyperpolarization by dissolution dynamic nuclear polarization (DNP) is a versatile technique to dramatically enhance the magnetic resonance (NMR) signal intensity of insensitive long‐ T 1 spins such as 6 Li. The Li longitudinal relaxation lithium ions in aqueous solutions strongly depends on concentration paramagnetic species, even if they are present minute amounts. We herein demonstrate that blood oxygenation can be readily detected taking advantage enhancement provided DNP, together with...

Recent years have witnessed increased efforts toward the accelerated acquisition of multidimensional nuclear magnetic resonance (nD NMR) spectra. Among methods proposed to speed up these NMR experiments is “projection reconstruction,” a scheme based on reduced number two-dimensional (2D) data sets constituting cross sections nD time domain being sought. Another proposition involves “ultrafast” spectroscopy, capable completing acquisitions within single scan. Potential limitations approaches...

Glucose is the primary fuel for brain; its metabolism linked with cerebral function. Different magnetic resonance spectroscopy (MRS) techniques are available to assess glucose metabolism, providing complementary information. Our first aim was investigate difference between hyperpolarized 13C-glucose MRS and non-hyperpolarized 2H-glucose interrogate glycolysis. Isoflurane anesthesia commonly employed in preclinical MRS, but it affects hemodynamics functional connectivity. A combination of low...

Länger leben dank Vitamin C: N-Oxid-Radikale, die weithin zur dynamischen Kernpolarisation eingesetzt werden, können beim Auflösen durch Abfangreagentien wie Natriumascorbat (Vitamin C) reduziert wodurch Polarisierungsverluste während des Transfers vermieden und transversale longitudinale Relaxationszeiten in NMR-spektroskopischen Experimenten verlängert werden (siehe Bild). Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents...