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Glutamate, a major neurotransmitter in the brain, shows a pH- and concentration-dependent chemical exchange saturation transfer effect (GluCEST) between its amine group and bulk water, with potential for in vivo imaging by nuclear magnetic resonance. GluCEST asymmetry is observed ∼3 p.p.m. downfield from bulk water. Middle cerebral artery occlusion in the(More)
Gamma-aminobutyric acid (GABA) and glutamate are implicated in numerous neuropsychiatric and substance abuse conditions, but their spectral overlap with other resonances makes them a challenge to quantify in humans. Gabapentin, marketed for the treatment of seizures and neuropathic pain, has been shown to increase in vivo GABA concentration in the brain of(More)
In vivo measurement of glutamate (Glu) in brain subcortex can elucidate the role these structures play in cognition and neuropsychiatric disorders. However, accurate quantification of Glu in subcortical regions is challenging. Recently, a novel MRI method based on the Glu chemical exchange saturation transfer (GluCEST) effect has been developed for(More)
Myo-Inositol (MI) is one of the most abundant metabolites in the human brain located mainly in glial cells and functions as an osmolyte. The concentration of MI is altered in many brain disorders including Alzheimer's disease and brain tumors. Currently available magnetic resonance spectroscopy (MRS) methods for measuring MI are limited to low spatial(More)
The sensitivity of chemical exchange saturation transfer (CEST) on glycosaminoglycans (GAGs) in human knee cartilage (gagCEST) in vivo was evaluated at 3 and 7 T field strengths. Calculated gagCEST values without accounting for B(0) inhomogeneity (~0.6 ppm) were >20%. After B(0) inhomogeneity correction, calculated gagCEST values were negligible at 3 T and(More)
A lipid-encapsulated perfluorocarbon nanoparticle molecular imaging contrast agent that utilizes a paramagnetic chemical exchange saturation transfer (PARACEST) chelate is presented. PARACEST agents are ideally suited for molecular imaging applications because one can switch the contrast on and off at will simply by adjusting the pulse sequence parameters.(More)
The effects of radio frequency field (B(1)) inhomogeneity on measured in vivo human brain glutamate chemical exchange saturation transfer contrast maps are normally confounded with contributions from chemical exchange saturation transfer, direct saturation and magnetization transfer effects. Consequently, the chemical exchange saturation transfer effect(More)
In the current study, we aim to measure T1rho (T (1ρ)) in the hippocampus in the brain of control, Alzheimer's disease (AD), Parkinson's disease (PD), and PD patients with dementia (PDD), and to determine efficacy of T (1ρ) in differentiating these cohorts. With informed consent, 53 AD patients, 62 PD patients, 11 PDD patients, and 46 age-matched controls(More)
Myo-inositol (mIns) is a marker of glial cells proliferation and has been shown to increase in early Alzheimer's disease (AD) pathology. mIns exhibits a concentration dependent chemical-exchange-saturation-transfer (CEST) effect (MICEST) between its hydroxyl groups and bulk water protons. Using the endogenous MICEST technique brain mIns concentration and(More)
PURPOSE To develop a chemical exchange saturation transfer (CEST)-based technique to measure free creatine (Cr) and to validate the technique by measuring the distribution of Cr in muscle with high spatial resolution before and after exercise. METHODS Phantom studies were performed to determine contributions from other Cr kinase metabolites to the CEST(More)