Use of high resolution in vivo volume selected 1H-magnetic resonance spectroscopy to investigate leukemia in humans.

In vivo high resolution volume-selected 1H magnetic resonance spectroscopy of human tibia has been undertaken using spatial coordinates obtained from magnetic resonance images. Adult tibial marrow has a 1H spectrum rich in fatty acid resonances and is readily distinguished from the 1H spectra of surrounding leg muscle. In all four leukemic patients examined, infiltration of fat cells of tibial marrow by proliferating cells rich in mobile H2O protons was evident by magnetic resonance imaging.

Does local intestinal ascorbate deficiency predispose to fistula formation in Crohn's disease.

Samples of maximally diseased and adjacent macroscopically normal intestine from 52 patients undergoing surgery for Crohn's disease were analyzed for ascorbate content; 26 of the patients had intestinal fistulas and 26 did not. Ascorbate analyses were also performed on samples of normal intestine from ten control patients. Diseased intestine from both groups of patients with Crohn's disease contained significantly more ascorbate than the adjacent macroscopically normal intestine.

Hormonal and metabolic responses to glucose infusion in sepsis studied by the hyperglycemic glucose clamp technique.

Although nutritional support is vital to treatment of severe sepsis, the septic patient does not respond normally to glucose infusion. We have used the hyperglycemic glucose clamp technique to investigate the initial hormonal and metabolic responses of the septic patient to glucose under controlled conditions. The plasma glucose concentration was raised to and maintained at 12 mmol/liter for 2 hr in 12 septic patients and 11 normal controls.

A comparison of some gradient-encoded volume-selection techniques for in vivo NMR spectroscopy.

Four of the techniques proposed for in vivo volume-selected NMR spectroscopy have been compared using a simple phantom with a large background water signal which was outside the region of interest. The methods VSE, SPACE, SPARS, and DIGGER all use pulsed field gradients for spatial encoding and were tested with a symmetric and an asymmetric phantom. SPACE was used to obtain volume-selected 1H NMR spectra of a human leg, demonstrating excellent discrimination between bone marrow and muscle.

The surgical management of pancreatic abscess.

In the past 6 years we have operated on 13 patients with pancreatic abscess. Sepsis recurred in all 12 in whom the primary procedure was closed drainage. Following further surgical debridement of these recurrent abscesses 2 patients had further closed drainage and in 10 the cavities were packed open to heal by granulation.

In vivo determination of body iron stores by natural-abundance deuterium magnetic resonance spectroscopy.

Induction of iron overload in mice using 1% (w/w) dietary carbonyl iron resulted in marked decreases in 1H and 31P NMR relaxation times. Natural-abundance deuterium (2H) NMR spectroscopy has been used to measure 2H T1 values in vivo in the presence of body paramagnetic iron. This procedure offers a method for noninvasive determination of body iron stores.

Calcium signals recorded from cut frog twitch fibers containing antipyrylazo III.

The Ca indicator antipyrylazo III was introduced into cut frog twitch fibers by diffusion (Maylie, J., M. Irving, N.

Comparison of arsenazo III optical signals in intact and cut frog twitch fibers.

The Ca indicator arsenazo III was introduced into cut frog twitch fibers by diffusion from end-pool segments rendered permeable by saponin. After 2-3 h, the arsenazo III concentration at the optical recording site in the center of a fiber reached two to three times that in the end-pool solutions. Thus, arsenazo III was bound to or taken up by intracellular constituents.

Calcium signals recorded from cut frog twitch fibers containing tetramethylmurexide.

The Ca indicator tetramethylmurexide was introduced into cut fibers, mounted in a double-Vaseline-gap chamber, by diffusion from the end-pool solutions. The indicator diffused rapidly to the central region of a fiber where optical recording was done and, if removed, diffused away equally fast. The time course of concentration suggests that, on average, a fraction 0.

Intrinsic optical and passive electrical properties of cut frog twitch fibers.

This article describes a new apparatus for making simultaneous optical measurements on single muscle fibers at three different wavelengths and two planes of linear polarization. There are two modes of operation: mode 1 measures the individual absorbances of light linearly polarized along and perpendicular to the fiber axis, and mode 2 measures retardation (or birefringence) and the average of the two absorbance components. Although some intact frog twitch fibers were studied, most experiments used cut fibers (Hille, B.

Nutritional management of pregnancy in patients on home parenteral nutrition.

Three pregnancies are reported in two patients on home parenteral nutrition for intestinal failure. The nutritional regimen, 2300 kcal (9.63 MJ) (18% as lipid emulsion), 14 g amino acid nitrogen and electrolytes supplied daily in a 'big bag', was based on the measured resting energy expenditure and urinary nitrogen excretion during the third trimester in a 30-year-old woman on home parenteral nutrition.

The utilization of two frequency-shifted sinc pulses for performing volume-selected in vivo NMR spectroscopy.

A new approach to volume-selected in vivo NMR spectroscopy uses two frequency-shifted sinc pulses, in conjunction with pulsed field gradients, to destroy the coherence of the unwanted signals. A hard pi/2 pulse can then be used to read the z magnetization in the region of interest. This method is independent of T2, provides complete volume selection in a single acquisition, and can be readily implemented on most high-field commercial imaging/spectroscopy systems.

Magnetic resonance imaging--first human images in Australia.

The use of magnetic resonance imaging, in the demonstration of internal human anatomy and in the diagnosis of disease, has the major advantages that the technique is noninvasive, does not require the use of ionizing radiation and that it can demonstrate neurological and cardiovascular lesions that cannot be diagnosed easily by other imaging methods. Magnetic resonance imaging is derived from the principle that certain atomic nuclei in a strong magnetic field will absorb pulses of radiofrequency energy; when the pulse is finished the nuclei will emit radiowaves at the same frequency. These radiowaves are received by specially designed aerials or coils and the information is collected by a computer which reconstructs an image of internal anatomy in a similar way to that of x-ray computed tomography (CT).

Effects of nutrient intake, surgery, sepsis, and long term administration of steroids on muscle function.

The stimulated contraction-relaxation characteristics of the adductor pollicis muscle were used to assess nutritional state in patients and healthy controls. In both groups insufficient nutrition resulted in abnormal muscle function. The ratio of force of contraction at 10 Hz to that at 20 Hz yielded the best combination of sensitivity (87%) and specificity (82%).

Home parenteral nutrition in the United Kingdom and Ireland.

Between January, 1977, and March, 1986, 200 patients were registered as receiving home parenteral nutrition (HPN) in the UK and the Republic of Ireland. Although 28 centres contributed case-reports, 75% of the cases were registered by 7 centres. Most patients started treatment between the ages of 10 and 40 years, a reflection of the high incidence of Crohn's disease during these decades.

Preliminary studies on the potential of in vivo deuterium NMR spectroscopy.

Natural abundance deuterium NMR spectroscopy can be used to characterise in vivo 2H signals arising from water and fat in mice, with acquisition times of less than two minutes. Administration of D(2)0 (10% V/V) in the drinking water enhances these signals so that excellent spectra can be obtained with one scan. Using these procedures the in vivo turnover of 2H in water and fat in mice has been determined.

Essential trace element provision to patients receiving home intravenous nutrition in the United Kingdom.

The methods of provision of essential trace elements to patients receiving long-term home intravenous nutrition in the U.K. have been reviewed and their trace element status has been assessed.

Use of inversion spin transfer to monitor creatine kinase kinetics in rat skeletal muscle in vivo.

A simple multipulse sequence has been used to monitor creatine kinase kinetics in rat skeletal muscle in vivo. Using these procedures, the forward (ATP synthesis) and reverse fluxes (phosphocreatine synthesis) have been calculated to be 8.98 +/- 0.

'Laparostomy': a technique for the management of intractable intra-abdominal sepsis.

Following laparotomy for severe intra-abdominal sepsis, the abdominal cavity was left open to heal by granulation in 18 patients. In 14 patients, operation was required because of recurrent gastrointestinal perforation or anastomotic dehiscence. In three, the indication for this procedure was recurrent pancreatic abscess.

In vivo determination of 31P spin relaxation times (T1, T2, T1 rho) in rat leg muscle. Use of an off-axis solenoid coil.

A probe using a solenoid coil tilted 45 degrees off-axis has been used to study the 31P NMR relaxation characteristics of the resonances arising from phosphorus metabolites in rats in vivo. T1, T1 rho and T2 values have been determined for phosphocreatine and ATP in leg muscle. The ratio of 31P T1(1700ms) to T2(12ms) for ATP was in excess of 200:1 compared with a ratio of 5:1 for 1H T1:T2.