Neurotoxicology and teratology
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Neurotoxicol Teratol · Jan 2013
Randomized Controlled TrialEffects of acetazolamide on cognitive performance during high-altitude exposure.
High-altitude hypoxia impedes cognitive performance. It is not well known whether the prophylactic use of acetazolamide for altitude sickness can influence cognitive performance at high altitude. When ascending to high altitude locations, one may face medical risks, including cognitive impairment, which may significantly hinder climbing abilities or exploratory behavior. ⋯ At high altitude, acetazolamide impaired rather than improved neuropsychological measures of concentration, cognitive processing speed, reaction time, short-term memory, and working memory, which were assessed by DSST, PASAT, and operation span task at 6 and 30 h after arrival (p<0.05). However, the prophylactic use of acetazolamide was found to reduce the incidence of AMS compared to the placebo (p<0.05). In conclusion, acetazolamide impairs neuropsychological function, at least in part, shortly after the ascent to high altitude.
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Neurotoxicol Teratol · Sep 2012
Investigation of calcium-stimulated adenylyl cyclases 1 and 8 on toluene and ethanol neurobehavioral actions.
The abused inhalant toluene has potent behavioral effects, but only recently has progress been made in understanding the molecular pathways that mediate the action of toluene in the brain. Toluene and ethanol induce similar behavioral effects and share some targets including NMDA and GABA receptors. In studies examining neuronal actions of ethanol, mice lacking the calcium-stimulated adenylyl cyclases (ACs), AC1 and AC8 (DKO), show increased sedation durations and impaired protein kinase A (PKA) phosphorylation following acute ethanol treatment. ⋯ In WT mice, both doses of ethanol increased distance traveled compared to saline controls. Conversely, DKO mice demonstrated no increase in locomotor activation at 1.0g/kg, with significantly reduced distances traveled at both doses compared to ethanol-treated WT mice. These behavioral activity results suggest that acute effects of ethanol and toluene are distinct in the mechanisms by which they induce acute sedating effects with respect to AC1 and AC8 activity, but may be similar in the mechanisms subserving locomotor stimulation.
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Neurotoxicol Teratol · Jan 2012
Randomized Controlled TrialA pilot study of preemptive morphine analgesia in preterm neonates: effects on head circumference, social behavior, and response latencies in early childhood.
Use of preemptive analgesia in Neonatal Intensive Care Units is recommended for severe and/or invasive procedures. However, the potential long-term consequences of such analgesia, which may be prolonged, are only beginning to be studied. In this pilot study, a subset of subjects previously enrolled in the Neurological Outcomes and Preemptive Analgesia in Neonates (NEOPAIN) trial was assessed at early childhood. ⋯ Parents described morphine treated children as having more social problems, an effect specific to creating and maintaining friendships (Cohen'sd: -0.83, effect size large). Despite the small sample size and the preliminary nature of this study, these results are strongly suggestive of long-lasting effects of preemptive morphine analgesia. A larger investigation with more comprehensive assessments of some of these key features will enable a more complete understanding of the relationship between preemptive morphine treatment and long-term neurocognitive, behavioral, and adaptive outcomes.
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Neurotoxicol Teratol · Jan 2012
Comparative StudyCharacteristics and behaviors of mothers who have a child with fetal alcohol syndrome.
Fetal alcohol syndrome (FAS) is a leading cause of birth defects and developmental disabilities. The objective of this study was to identify the characteristics and behaviors of mothers of children with FAS in the United States using population-based data from the FAS Surveillance Network (FASSNet). FASSNet used a multiple source methodology that identified FAS cases through passive reporting and active review of records from hospitals, specialty clinics, private physicians, early intervention programs, Medicaid, birth certificates and other vital records, birth defects surveillance programs, and hospital discharge data. ⋯ A significant proportion of mothers (9-29%) had another child with suspected alcohol effects. Compared to all US mothers, they were also significantly more likely to be on public assistance, to be on Medicaid at their child's birth, to have received treatment for alcohol abuse, to have confirmed alcoholism, to have used marijuana or cocaine during pregnancy, to have their baby screen positive for alcohol or drugs at birth, to have had an induced abortion, to have had a history of mental illness, to have been involved in binge drinking during pregnancy, and to have drunk heavily (7 days/week) during pregnancy. These findings suggest that it is possible to identify women who are at high risk of having a child with FAS and target these women for interventions.
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Neurotoxicol Teratol · Nov 2011
Cytoarchitectonic and neurochemical differentiation of the visual system in ethanol-induced cyclopic zebrafish larvae.
Embryonic exposure to ethanol leads to malformations such as cyclopia. Cyclopic embryos present fused eyes and lack of the ventral specification of the brain, with physiological and morphological defects in the visual system, which provides a useful model for teratology and neurotoxicity assessments. We analysed the differentiation of the visual areas in the ethanol-induced cyclopic animals. ⋯ We found that the alterations produced by exposure to ethanol are not only cell-selective, but also tissue-selective. Cyclopia is the most severe phenotype induced by ethanol, although cell differentiation and proliferation can reach normal patterns after a certain period of time, which points to a neural plasticity process. Zebrafish embryos may possess a compensation mechanism against the ethanol effect, which would account for their use for pharmacogenetic and chemical screenings in the analysis of new molecules that could improve visual problems.