Demonstration and localization of neuronal degeneration in the rat forebrain following a single exposure to MDMA
BRAIN RESEARCH
Authors: Schmued, LC
Abstract
Methylenedioxymethamphetamine (MDMA, Ecstasy) is a powerful releaser of serotonin. Increasing recreational use of this stimulant and hallucinogenic drug has raised concerns about its potential to produce brain damage. The vast majority of previous research studies have focused on the compound's ability to deplete serotonin (5-hydroxytryptamine, 5-HT) from axon terminals. Despite extensive research on this '5-HT terminal neurotoxicity', a much less studied aspect of MDMA toxicity involves its ability to actually kill nerve cells. Only two prior studies mention the existence of MDMA-induced neuronal degeneration, as reflected by a limited number of argyrophylic neurons within the somatosensory cortex, following very high doses of MDMA. The development of Fluoro-Jade B as a simple and reliable marker of neuronal degeneration has allowed us to conduct the first comprehensive localization of MDMA induced neuronal degeneration throughout the entire rat forebrain. In addition to the previously reported neuronal degeneration within parietal cortex, degenerating neurons were also observed in the insular/perirhinal cortex, the ventromedial/ventrolateral thalamus, and the tenia tecta. The extent of neuronal degeneration observed generally correlated with the degree of hyperthermia achieved. Published by Elsevier Science B.V.
A new, automated rapid fluorometric method for the detection of Escherichia coli in recreational waters
JOURNAL OF GREAT LAKES RESEARCH
Authors: Bramburger, Andrew J.; Brown, R. Stephen; Haley, Jennifer; Ridal, Jeffrey J.
Abstract
Membrane filtration/culture techniques have been demonstrated to be reliable and broadly applicable for determination of fecal contamination in recreational waters. The time-consuming nature of culture techniques, however, is viewed as the major disadvantage of this type of analysis, and many authors have asserted the need for improved rapid-detection methods. In this study, we evaluated the performance of the ENDETEC (TM) TECTA (TM) B16, an automated fluorometty-based microbial detection system, by comparing its detection time and accuracy to those of two common culture-based methods, which are widely-used for recreational water quality monitoring in Canada. Our results demonstrated that Escherichia coli densities inferred by the TECTA (TM) method were generally in agreement with those generated by standard culture methods (y = 1.19x + 0.002, R-2 = 0.89) and under the current calibration regime, TECTA (TM) tended to slightly overestimate E. coli densities. In addition, TECTA (TM) was able to detect E. coli densities in exceedance of the Ontario Provincial Water Quality Objective for recreational waters in as little as 4 h (mean detection time = 7.03 h), representing a substantial improvement over traditional culture techniques. Our findings suggest that with improved calibration, TECFA (TM) may provide a viable, cost-effective, rapid alternative to culture approaches for the detection of fecal contamination in recreational waters. (c) 2014 International Association for Great Lakes Research. Published by Elsevier BAT. All rights reserved.