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CONTEXT Major depressive disorder (MDD) is characterized by diverse metabolic and functional abnormalities that occur in, among other regions, the pregenual anterior cingulate cortex (pgACC), a cortical region linked to anhedonia. OBJECTIVES To contextualize metabolic, functional, and clinical parameters and thus to reveal cellular mechanisms related to(More)
The human anterior cingulate cortex (ACC) is part of the default-mode network that shows predominant negative blood oxygen level-dependent (BOLD) responses in functional magnetic resonance imaging (fMRI). We combined fMRI during emotional processing and resting-state magnetic resonance spectroscopy measurements and observed that the concentration of GABA in(More)
Localised two-dimensional J-resolved spectroscopy (JPRESS) is optimised for the in vivo detection of J-coupled metabolites using magnetic resonance spectroscopy at 3 T. The acquisition of echo signals starts as early as possible (i.e. maximum-echo sampling). This sampling scheme increases sensitivity and decreases overlap of peak tails, hence alleviating(More)
Real-time in vivo measurements of metabolites are performed by signal enhancement of [1-(13)C]pyruvate using dynamic nuclear polarization, rapid dissolution and intravenous injection, acquisition of free induction decay signals and subsequent quantification of spectra. The commonly injected dose of hyperpolarized pyruvate is larger than typical tracer(More)
A two-dimensional fitting procedure is introduced, capable of extracting the full amount of information from 2D J-resolved magnetic resonance spectroscopic data. The fitting procedure uses a linear combination of 2D model spectra. For reducing the degrees of freedom and increasing robustness, it is divided into a non-linear outer loop and an inner linear(More)
Two-dimensional (2D) strong-coupling point-resolved spectroscopy (S-PRESS) is introduced as a novel approach to (1)H MR spectroscopy (MRS) in the prostate. The technique provides full spectral information and allows for an accurate characterization of the citrate (Cit) signal. The method is based on acquiring a series of PRESS spectra with constant total(More)
PURPOSE The metabolism of acetate in the heart resembles fatty acid metabolism, which is altered in several diseases like ischemia, diabetes mellitus, and heart failure. A signal-to-noise ratio (SNR) optimized imaging framework for in vivo measurements of hyperpolarized [1-(13) C]acetate and its metabolic product [1-(13) C]acetylcarnitine (ALCAR) in rats at(More)
The achievable bandwidth of common linear-phase RF pulses is limited by the maximum feasible B1 amplitude of the MR system. It has been shown previously, that this limitation can be circumvented by overlaying a quadratic phase in the frequency domain, which spreads the power across the pulse duration. Quadratic-phase RF pulses are near optimal in terms of(More)
In the metabolism of acetate several enzymes are involved, which play an important role in free fatty acid oxidation. Fatty acid metabolism is altered in diabetes patients and therefore acetate might serve as a marker for pathological changes in the fuel selection of cells, as these changes occur in diabetes patients. Acetylcarnitine is a metabolic product(More)
A chemical-shift-selective filter (CSSF) was applied to the detection of J-coupled metabolites in the human brain. This filter is an acquisition-based technique that requires the chemical shifts (CS's) of different metabolites, but not their whole multiplet structures, to be resolved. The sequence is based on the 2D constant-time spin-echo experiment, which(More)