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I DeLeon

Publications and source records attributed to I DeLeon.

3 recordsLinked to original sources

Self-injurious behavior: gene-brain-behavior relationships.

This paper summarizes a conference held at the National Institute of Child Health and Human Development on December 6-7, 1999, on self-injurious behavior [SIB] in developmental disabilities. Twenty-six of the top researchers in the U.S. from this field representing 13 different disciplines discussed environmental mechanisms, epidemiology, behavioral and pharmacological intervention strategies, neurochemical substrates, genetic syndromes in which SIB is a prominent behavioral phenotype, neurobiological and neurodevelopmental factors affecting SIB in humans as well as a variety of animal models of SIB. Findings over the last decade, especially new discoveries since 1995, were emphasized. SIB is a rapidly growing area of scientific interest to both basic and applied researchers. In many respects it is a model for the study of gene-brain-behavior relationships in developmental disabilities.

Animals↗

The effects of d-amphetamine and diazepam on schedule-induced defecation in rats.

The effects of d-amphetamine (0.32 to 5.6 mg/kg) and diazepam (0.10 to 5.6 mg/kg) on defecation were examined in two groups of rats. One group was exposed to a fixed-time 60-s (FT 60-s) schedule of food delivery and the other group was exposed to massed-food sessions. During vehicle control sessions, rats exposed to the FT 60-s schedule excreted a significantly higher number of fecal boli than rats exposed to massed-food sessions. d-Amphetamine, at doses above 0.56 mg/kg, significantly reduced defecation (boli produced) in both groups, although the magnitude of the drug's effect was larger in the group exposed to the FT 60-s schedule. For both groups, diazepam only produced a significant decrease in defecation at the highest dose (5.6 mg/kg). These results appear to be inconsistent with interpretations of adjunctive behavior that emphasize arousal or emotion as mechanisms.

Animals↗

Human absorption of crude coal tar products.

Five normal adult volunteers without cutaneous disease applied 2% crude coal tar to the skin for eight-hour periods on two consecutive days. Blood extracts subjected to gas chromatography and mass spectrometry yielded evidence of absorption in all five volunteers. Phenanthrene, anthracene, pyrene, and fluoranthene, found in four of our volunteers, have been shown to be tumor initiators or cocarcinogens.

Adult↗