Measuring the neural response to continuous intramuscular infusion of hypertonic saline by perfusion MRI.

Purpose: To determine the extent to which arterial spin labeling (ASL), a functional magnetic resonance imaging technique that directly measures cerebral blood flow (CBF), is able to measure the neural activation associated with prolonged experimental muscle pain.

Materials And Methods: Hypertonic saline (HS) (5% NaCl) was infused into the brachioradialis muscle of 19 healthy volunteers for 15 min. The imaging volume extended from the dorsal side of the pons to the primary somatosensory cortices, covering most of the cortical and subcortical regions associated with pain perception.

Using perfusion MRI to measure the dynamic changes in neural activation associated with tonic muscular pain.

Knowledge regarding neural pain processing is primarily the result of studies involving models of brief cutaneous pain; however, clinical pain generally originates in deep tissue and is prolonged. This study measured the dynamic neural activation associated with a muscular pain model incorporating both acute and tonic states. Hypertonic saline (5% NaCl) was infused into the brachioradialis muscle of eleven healthy volunteers for 15min after an initial bolus of 0.

Potentiation of cell killing by low-dose-rate radiation by camptothecin is related to an increase in the level of DNA double-strand breaks.

We investigated the ability of camptothecin to potentiate cell killing by low-dose-rate irradiation and whether this potentiation was associated with an increase in the level of residual DNA double-strand breaks (DSBs). Human melanoma (Sk-Mel-3) cells, grown to the confluent phase, were treated with low-dose-rate radiation (0.88 cGy/min) alone, camptothecin alone, or concurrent camptothecin and low-dose-rate radiation.