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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)
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)
Glutamate (Glu) is the most abundant excitatory neurotransmitter in the brain and spinal cord. The concentration of Glu is altered in a range of neurologic disorders that affect the spinal cord including multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS) and spinal cord injury. Currently available magnetic resonance spectroscopy (MRS) methods for(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)
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)
Creatine (Cr), phosphocreatine (PCr) and adenosine-5-triphosphate (ATP) are major metabolites of the enzyme creatine kinase (CK). The exchange rate of amine protons of CK metabolites at physiological conditions has been limited. In the current study, the exchange rate and logarithmic dissociation constant (pKa) of amine protons of CK metabolites were(More)
Clinically, development of anti-angiogenic drugs for cancer therapy is pivotal. Longitudinal monitoring of tumour angiogenesis can help clinicians determine the effectiveness of anti-angiogenic therapy. Blood oxygen level dependent (BOLD) effect has been widely used for functional imaging and tumour oxygenation assessment. In this study, the BOLD effect is(More)
Noninvasive molecular imaging of angiogenesis could play a critical role in the clinical management of peripheral vascular disease patients. The alpha(nu)beta(3)-integrin, a well-established biomarker of neovascular proliferation, is an ideal target for molecular imaging of angiogenesis. This study investigates whether MR molecular imaging with(More)
Perfluorocarbon (PFC) nanoparticles can serve as a platform technology for molecular imaging and targeted drug-delivery applications. These nanoparticles are approximately 250 nm in diameter and are encapsulated in a phospholipid shell, which provides an ideal surface for the incorporation of targeting ligands, imaging agents and drugs. For molecular(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)