Amos Lanir

MR imaging in myelofibrosis.

Two patients with myelofibrosis demonstrated decreased signal intensity from the bone marrow due to replacement of marrow fat with fibrosis and cellular elements.

Liver adenine nucleotide metabolism during ischemia and reperfusion of mice livers studied by phosphorous-31 nuclear magnetic resonance.

Perfusion experiments were performed at 20 degrees C and 37 degrees C to study liver adenine nucleotide metabolism during ischemia and reperfusion of mouse livers using 31P NMR. Perfusing at 8 mL/min (Krebs-Henseleit buffer), ATP was shown to be stable for 6 hours. There was a progressive decrease in the phosphodiesters (glycerophosphorycholine and glycerophosphorylethanolamine) during the 6-hour period. Liver subjected to cold ischemia at 20 degrees C showed a slow decrease in the beta ATP peak during a 42 +/- 6-minute period with a rise in the inorganic phosphate accompanied by a shift of inorganic phosphate to the high field indicating intracellular acidosis. With reperfusion, the beta ATP returned to previous levels and the inorganic phosphate shifted to its original position. During warm ischemia (37 degrees C) the ATP peak disappeared within 5 +/- 1 minute and only returned to 34% of its original value after 30 minutes of ischemia, indicating damage to a certain percentage of liver cells. When the liver was subjected to multiple short periods of cold ischemia, there was complete recovery of the ATP after six cycles. Reperfusion after each period of cold ischemia resulted in an ATP recovery consistently greater than the initial amount, which gradually decreased to preischemic levels after a short period. This suggests that there is an as yet undelineated mechanism of ATP production during ischemia that attempts to protect the cell against ischemia.

Nuclear Magnetic Resonance Assessment of Adenosine Triphosphate (atp) Dynamics in Ischemic Mouse Livers Perfused with Adenine and Ribose

Hepatic energy stores are essential to liver viability. We used a mouse liver perfusion model and MR spectroscopy to study the effect of adding two precursors of ATP (adenine and ribose) on ATP dynamics during ischemia and reperfusion. Using Krebs-Henseleit buffer with or without added adenine and ribose made little difference in the ATP decay rate during ischemia, but the recovery of ATP during reperfusion was more complete when adenine and ribose were added to the buffer. These findings suggest that the addition of the precursors of ATP, adenine and ribose, to perfusate after ischemia can accelerate and enhance ATP recovery.

Magnetic resonance imaging of gynecologic masses

The pelvis of 21 women with various gynecological masses were imaged with magnetic resonance (MR) imagers at 2.0 and 0.5 T. Fifteen normal individuals were used for studying the normal appearance of the female genitalia using spin echo pulse sequences with various pulse repetition (TR) and spin echo (TE) time values. Images were compared with those of the ultrasonic images, intraoperative findings, and the histopathologic examinations. The masses included simple ovarian cyst, cystadenoma, serous cystadenocarcinoma, ovarian teratoma, dysgerminoma, and uterine myoma. MR imaging was useful in demonstrating the anatomy and pathology of the cases examined in this study. It detected the internal structure of some tumors which were sonographically homogeneous. The potential of MR in staging of malignancies was demonstrated.

31P nuclear magnetic resonance evaluation of intermittent perfusion as a method of liver preservation.

La perfusion intermittente est plus efficace que la simple hypothermie pour la conservation de foies a transplanter, mais elle ne peut pas remplacer couramment la perfusion continue