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By quantification of brain metabolites, localized brain proton MRS can non-invasively provide biochemical information from distinct regions of the brain. Quantification of short-TE signals is usually based on a metabolite basis set. The basis set can be obtained by two approaches: (1) by measuring the signals of metabolites in aqueous solution; (2) by(More)
The development of new diagnostic criteria for Alzheimer's disease (AD) requires new in vivo markers reflecting early pathological changes in the brain of patients. Magnetic resonance (MR) spectroscopy has been shown to provide useful information about the biochemical changes occurring in AD brain in vivo. The development of numerous transgenic mouse models(More)
The broad resonances underlying the entire (1) H NMR spectrum of the brain, ascribed to macromolecules, can influence metabolite quantification. At the intermediate field strength of 3 T, distinct approaches for the determination of the macromolecule signal, previously used at either 1.5 or 7 T and higher, may become equivalent. The aim of this study was to(More)
In (1)H magnetic resonance spectroscopy, macromolecule signals underlay metabolite signals, and knowing their contribution is necessary for reliable metabolite quantification. When macromolecule signals are measured using an inversion-recovery pulse sequence, special care needs to be taken to correctly remove residual metabolite signals to obtain a pure(More)
* Quantification of short-echo time proton magnetic resonance spectroscopy results in >18 metabolite concentrations (neuro-chemical profile). Their quantification accuracy depends on the assessment of the contribution of macromolecule (MM) resonances, previously experimentally achieved by exploiting the several fold difference in T 1. To minimize effects of(More)
Hepatic encephalopathy (HE) is a common and severe neuropsychiatric complication present in acute and chronic liver disease. The unique advantages of high field 1H MRS provide a method for assessing pathogenic mechanism, diagnosis and monitoring of HE, as well as for treatment assessment or recovery after liver transplantation, in a reproducible and(More)
In vivo localized proton magnetic resonance spectroscopy (1H MRS) became a powerful and unique technique to non-invasively investigate brain metabolism of rodents and humans. The main goal of 1H MRS is the reliable quantification of concentrations of metabolites (neurochemical profile) in a well-defined region of the brain. The availability of very high(More)
The recent developments in high magnetic field 13C magnetic resonance spectroscopy with improved localization and shimming techniques have led to important gains in sensitivity and spectral resolution of 13C in vivo spectra in the rodent brain, enabling the separation of several 13C isotopomers of glutamate and glutamine. In this context, the assumptions(More)
Introduction: In hyperammonemic conditions, glutamine is generated in astrocytes from ammonia and glutamate in a reaction catalyzed by glutamine synthetase. Recent in vitro observations suggested that during hyperammonemia, alterations in brain metabolites other than glutamine can occur (i.e. glutamate, myo-inositol, taurine, lactate) (1,2). In addition, it(More)
Manganese (Mn(2+))-enhanced magnetic resonance imaging studies of the neuronal pathways of the hypothalamus showed that information about the regulation of food intake and energy balance circulate through specific hypothalamic nuclei. The dehydration-induced anorexia (DIA) model demonstrated to be appropriate for studying the hypothalamus with(More)