PubMed · 5539734
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
1971-02-06. Cluster migraine.. https://pubmed.ncbi.nlm.nih.gov/5539734/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Cocaine is a highly psychoactive substance with numerous effects that readily crosses the placenta, achieving variables levels in the fetus. Determining whether prenatal exposure to cocaine and its metabolites damages the developing human nervous system is hindered by the multiple intervening factors (confounders) that plague clinical settings, which warrant consideration in controlled studies. Prenatal cocaine exposure has been linked to numerous adverse neonatal outcomes, affecting fetal growth (i.e., low birth weight, intrauterine growth retardation, and small head size) and neurobehavior. These neurobehavior effects span the gamut from no abnormalities to impairments in arousal, neurological function, neurophysiological function, and state regulation. Strokes and possibly seizures are also noted. Dose-response effects of fetal cocaine exposure on fetal growth and neonatal neurobehavior are reported using quantitative methods of ascertainment. In early infancy, irritability and hypertonia are also described. Most cocaine associations are transient and resolve in infancy and early childhood. Whether such transient abnormalities place infants at increased risk for later neurodevelopmental impairments is not known. Controlled studies have found no cognitive differences related to prenatal cocaine exposure among toddlers or school age children, except as mediated through effects on head growth. Anecdotally, cocaine-exposed children seem to suffer from neurobehavioral abnormalities, but to date controlled studies have not established an association between cocaine and behavioral disorders, except for inattentiveness. Despite encouraging reports, the question of whether cocaine exerts long-term adverse effects on the developing human nervous system has not yet been resolved, largely because of the limitations of existing studies that rely on inadequate, mostly qualitative ascertainment of cocaine exposure as well as the dearth of studies in older children. Such methodological limitations may have compromised our ability to identify cocaine-exposed children at most risk.
Explore the source record for details and available documents.
The present paper describes the methodological optimisation and validation of a capillary zone electrophoresis method for the determination of morphine, cocaine and 3,4-methylenedioxymethamphetamine (MDMA) in hair, with injection based on field-amplified sample stacking. Diode array UV absorption detection was used to improve analytical selectivity and identification power. Analytical conditions: running buffer 100 mM potassium phosphate adjusted to pH 2.5 with phosphoric acid, applied potential 10 kV, temperature 20 degrees C, injection by electromigration at 10 kV for 10 s, detection by UV absorption at the fixed wavelength of 200 nm or by recording the full spectrum between 190 and 400 nm. Injection conditions: the dried hair extracts were reconstituted with a low-conductivity solvent (0.1 mM formic acid), the injection end of the capillary was dipped in water for 5 s without applying pressure (external rinse step), then a plug of 0.1 mM phosphoric acid was loaded by applying 0.5 psi for 10 s and, finally, the sample was injected electrokinetically at 10 kV for 10 s. Under the described conditions, the limit of detection was 2 ng/ml for MDMA, 8 ng/ml for cocaine and 6 ng/ml for morphine (with a signal-to-noise ratio of 5). The lowest concentration suitable for recording interpretable spectra was about 10-20-times the limit of detection of each analyte. The intraday and day-to-day reproducibility of migration times (n = 6), with internal standardisation, was characterised by R.S.D. values < or = 0.6%; peak area R.S.D.s were better than 10% in intraday and than 15% in day-to-day experiments. Analytical linearity was good with R2 better than 0.9990 for all the analytes.