C.Tyler Burt

Principles of Nuclear Magnetic Resonance

The basic principles of nuclear magnetic resonance (NMR) are discussed. The concepts presented include a qualitative quantum-mechanical approach to NMR spectroscopy and a classical-mechanical approach to time-dependent NMR phenomena (relaxation effects). The spectroscopic concepts discussed include absorption of radiation by matter, spin and energy quantization , chemical shift, and spin-spin splitting. The time-dependent phenomena include the concepts of T1 and T2, the spin-lattice and spin-spin relaxation time, and Fourier-transform NMR spectroscopy.

A hypothesis: Noncyclic phosphodiesters may play a role in membrane control

The study of the metabolism of GPC and SEP has the potential to demonstrate a previously undiscovered method by which the cytosol can communicate with membrane.

Generation of phosphodiesters during fast-to-slow muscle transformation A 31P-NMR study

During rabbit fast-to-slow twitch muscle transformation, in response to electrical stimulation, the compound glycerophosphocholine can be detected in these muscles by 31P-NMR. This compound is not detectable in contralateral control muscles but is present in slow twitch soleus.

Multiple environments of fluorinated anesthetics in intact tissues observed with 19F NMR spectroscopy

The incorporation of two fluorine‐containing general anesthetic agents, halothane and methoxyflurane, into erythrocytes (from three different species), rabbit muscle and rabbit nerve, was followed with 19F NMR spectroscopy. Two major findings emerged from these studies: (1) multiple environments indicative of domain structure in the membrane can be observed depending on the anesthetic and the tissue type; and (2) the 19F chemical shifts of a given anesthetic were characteristic for the tissue examined. Halothane showed a single resonance in erythrocytes and multiple resonances in muscle and nerve, while methoxyflurane showed multiple resonances in both muscle and erythrocytes. The range of the 19F chemical shifts for the multiple peaks was as great as 6 ppm.

Unknown phosphate compounds in tail muscle of intact conscious newts by 31P NMR.

Unknown phosphate resonances at 0 and -21.6 ppm have been identified in 31P NMR spectra of tail muscle of unanesthetized newts which do not correspond to known phosphate-bearing compounds in skeletal muscle cells. The concentrations of both unknowns decrease markedly during muscular activity and severe hypoxia (conditions associated with decreased intracellular pH and increased cellular levels of inorganic phosphate). The unknown at 0 ppm increases in concentration with imposition of moderate hypoxia. Our data suggest that these unknowns may be liable storage compounds for a high energy phosphate bond, and are involved in newt skeletal muscle phosphogen metabolism.

NMR of live systems

Abstract Continuous non-destructive in vivo biochemical measurements have been a desired but seemingly unattainable goal for many years. Now, however, the use of nuclear magnetic resonance (NMR) seems to be close to reaching that end. This review can be divided into two sections. The first introduces and discusses relevant NMR parameters such as chemical shift and relaxation times form the view of their application to biologic systems. The second part highlights recent achievements by showing the variety of chores NMR can perform. In particular, the topics of pH measurement, quantitation and identification of phosphorus and carbon metabolites, and enzyme kinetics are all discussed. Also mentioned are limitations of NMR such as low sensitivity. Finally, there is a discussion of the new NMR technologies such as whole body proton imaging and topical NMR.