Solid-state NMR technique for measuring distances between heteronuclei in static powder samples is described. It is based on a two-dimensional single-echo scheme enhanced with adiabatic cross polarization. As an example, the results for intramolecular distances in alpha-crystalline form of glycine are presented. The measured NMR distances (13)C(alpha)-(15)N and (13)C(')-(15)N are 1.496+/-0.002 ...

Nuclear magnetic resonance (NMR) microscopy allows us to image and quantify the distribution of NMR-active nuclei in living specimens. Using high-field NMR microscopy at a magnetic field strength of 14.1 T and strong gradients up to 3 T m(-1), we show that separation of fat and water nuclear resonances in living insects can be achieved. In contrast to destructive conventional photometric and ma...

A spectroscopic imaging technique with high spatial resolution was used for the measurement of the static magnetic field homogeneity of RF coils. Measured magnetic fields of optimised and not optimised saddle-shaped coils were compared with the theoretical calculations. Results are in good qualitative agreement between calculated and measured magnetic field distributions. Quantitative disagreem...

Structural coronary microcirculation abnormalities are important prognostic determinants in clinical settings. However, an assessment of microvascular resistance (MR) requires a velocity wire. A first-pass distribution analysis technique to measure volumetric blood flow has been previously validated. The aim of this study was the in vivo validation of the MR measurement technique using first-pa...

Homonuclear 13C-13C couplings can significantly reduce the sensitivity and resolution of multidimensional NMR experiments. The most important of these couplings is the 13Calpha-13Cbeta coupling, and several different methods have been developed to eliminate its effect from spectra used for backbone assignment, including short or constant-time evolution periods, selectively labeled amino acids, ...

Dispersion remains, today, a highly topical subject. Our group has been interested in characterizing this phenomenon by pulsed-field-gradient NMR technique. Direct measurement of the dispersion coefficient can be done with a Pulsed Gradient Spin Echo (PGSE) sequence by assuming that the asymptotic regime is reached. In unsteady state, the propagator formalism is used. To better understand these...

INTRODUCTION: In vivo experiments conducted by infusing C labeled substrates (glucose and acetate) together with C NMR spectroscopy have given important insight for the neuronal and astroglial metabolism. These studies have established that neurotransmitter cycle is stoichiometrically coupled to the neuronal glucose oxidation indicating neurotransmitter energetics is supported by oxidative gluc...

In order to permit a more optimized selection of acquisition parameters for nuclear magnetic resonance (NMR) imaging a simulation procedure is proposed to determine the pulse sequences for optimal tissue contrast for a variety of clinical indications. In selected patient studies an adequate set of source images is measured, which allows computation of images of all possible pulse sequences, and...

1H NMR spectra from urine can yield information-rich data sets that offer important insights into many biological and biochemical phenomena. However, the quality and utility of these insights can be profoundly affected by how the NMR spectra are processed and interpreted. For instance, if the NMR spectra are incorrectly referenced or inconsistently aligned, the identification of many compounds ...

Localized C NMR spectroscopy provides a new investigative tool for studying cerebral metabolism. The application of C NMR spectroscopy to living intact humans and animals presents the investigator with a number of unique challenges. This review provides in the first part a tutorial insight into the ingredients required for achieving a successful implementation of localized C NMR spectroscopy. T...