Stochastic excitation with a full-width-half-maximum bandwidth of 250 MHz was used to perform Fourier-transform (FT) high-field/high-frequency electron paramagnetic resonance (EPR) at 3.4T/95 GHz (W-band). Thereby, the required microwave peak power is reduced by a factor of tau(p)/T1 as compared to equivalent pulsed FT EPR in which the spin system with spin-lattice relaxation time T1 is excited...

In order to facilitate the study of motions of the carbohydrate moiety of glycoproteins, a method of enzymatically attaching uniformly 13C-enriched galactopyranose ([U-13C]galactose) onto the nonreducing end of the carbohydrate chain has been developed. Specifically, [U-13C]glucose (20% 13C) was converted through a sequence of four enzymatic steps to [U-13C]UDP-galactose which was then attached...

Introduction T1ρ is the spin-lattice relaxation time in the rotating frame during application of an on-resonance spin-locking pulse. Recently, we reported an activation induced decrease of R1ρ (=1/ T1ρ) at the parenchyma of cat visual cortex [1]. It has been proposed by Hulvershorn et al. in a previous human visual stimulation study at 3 T that such functional T1ρ change can largely be attribut...

Aggregation in heat-treated Nafion ionomer dispersion and 117 membrane are investigated by 1H and 19F Nuclear Magnetic Resonance (NMR) spectra, spin-lattice relaxation time, and self-diffusion coefficient measurements. Results demonstrate that heat-treatment affects the average Nafion particle size in aqueous dispersions. Measurements on heat-treated Nafion 117 membrane show changes in the 1H i...

Background Mapping the longitudinal relaxation time (T1) is a promising quantitative tool for the detection of myocardial pathologies either in mouse or human. T1 maps are usually obtained in 2D in order to reduce the total scan time. However, to diagnose myocardial infarction it might be useful to obtain the T1 maps in three dimensions (3D) which require a long acquisition time. In this projec...

The transfer and distribution of paramagnetic manganese was investigated in the dually perfused human placenta in vitro (using 10, 20, 100 microM Mn with and without 54Mn) using magnetic resonance imaging (MRI) and conventional radiochemical techniques. The human placenta concentrated 54Mn rapidly during the first 15 min of perfusion and by 4 hr was four times greater than the concentrations of...

In magnetic resonance imaging, precise measurements of longitudinal relaxation time (T1) is crucial to acquire useful information that is applicable to numerous clinical and neuroscience applications. In this work, we investigated the precision of T1 relaxation time as measured using the variable flip angle method with emphasis on the noise propagated from radiofrequency transmit field ([Formul...

BACKGROUND AND AIM Hypothyroidism (HT) is characterized by thyroid hormone deficiencies, which can lead to diffuse myocardial interstitium lesions in patients with HT. Myocardial longitudinal relaxation time (T1) mapping is a potential diagnostic tool for quantifying diffuse myocardial injury. This study aimed to assess the usefulness of T1 mapping in identifying myocardial involvement in HT, a...

PURPOSE To use magnetic resonance imaging (MRI) at two field strengths to assess healthy adults' regional myocardial noncontrast (native) T1 relaxation time distribution, and global myocardial native T1 between sexes and across age groups. MATERIALS AND METHODS In all, 84 healthy volunteers underwent MRI at 1.5T and 3.0T. T1 maps were acquired in three left ventricular short axis slices using...

BACKGROUND AND PURPOSE The longitudinal relaxation time of blood (T 1b) is influenced by haematocrit (Hct) which is known to vary in neonates. The purpose of this study was threefold: to obtain T 1b values in neonates, to investigate how the T 1b influences quantitative arterial spin labelling (ASL), and to evaluate if known relationships between T 1b and haematocrit (Hct) hold true when Hct is...