Cognitive and Social Development in Preschool Children Born to Women Using Substances

Prenatal substance exposure is associated with physical birth defects and increased risk of regulatory and neuropsychological difficulties of children born to mothers using substances while pregnant. Myriad factors, such as maternal psychopathology, stress, and poor living circumstances, may influence childhood development in addition to the teratological effect of prenatal substance exposure. This study explores the long-term developmental consequences in children from birth to age 7 born to women using substances and are in treatment. A series of t tests were performed to explore group effects on the cognitive and social dimensions of Griffiths Mental Development Scales compared with Swedish norms. The results showed significant effects on eye and hand coordination in children aged birth to 7 years and on hearing and speech, practical reasoning, and the general quotient in children aged 3 to 7 years. Children who were exposed primarily to alcohol in utero scored significantly lower on the personal and social skills subscale, eye and hand coordination subscale, and the general quotient than children exposed primarily to substances other than alcohol. These effects did not appear to be mediated by the mothers’ social background or treatment history. The results suggest that children who are exposed to substances, in particular alcohol, in utero are vulnerable overall, but especially in eye and hand coordination and personal and social skills.     

The Influence of Age on Propofol Pharmacodynamics

Background: The authors studied the influence of age on the pharmacodynamics of propofol, including characterization of the relation between plasma concentration and the time course of drug effect.

Methods: The authors evaluated healthy volunteers aged 25-81 yr. A bolus dose (2 mg/kg or 1 mg/kg in persons older than 65 yr) and an infusion (25, 50, 100, or 200 [micro sign]g [middle dot] kg-1 [middle dot] min-1) of the older or the new (containing EDTA) formulation of propofol were given on each of two different study days. The propofol concentration was determined in frequent arterial samples. The electroencephalogram (EEG) was used to measure drug effect. A statistical technique called semilinear canonical correlation was used to select components of the EEG power spectrum that correlated optimally with the effect-site concentration. The effect-site concentration was related to drug effect with a biphasic pharmacodynamic model. The plasma effect-site equilibration rate constant was estimated parametrically. Estimates of this rate constant were validated by comparing the predicted time of peak effect with the time of peak EEG effect. The probability of being asleep, as a function of age, was determined from steady state concentrations after 60 min of propofol infusion.

Results: Twenty-four volunteers completed the study. Three parameters of the biphasic pharmacodynamic model were correlated linearly with age. The plasma effect-site equilibration rate constant was 0.456 min-1. The predicted time to peak effect after bolus injection ranging was 1.7 min. The time to peak effect assessed visually was 1.6 min (range, 1-2.4 min). The steady state observations showed increasing sensitivity to propofol in elderly patients, with C50 values for loss of consciousness of 2.35, 1.8, and 1.25 [micro sign]g/ml in volunteers who were 25, 50, and 75 yr old, respectively.     

Structural conformation and leaching from in vitro aged and retrieved Invisalign appliances

The objectives of this study were to investigate the structure of Invisalign appliances (Align Technology, Santa Clara, Calif) after intraoral exposure, and to qualitatively and quantitatively characterize the substances leached from the aligners after accelerated in vitro aging. Samples of Invisalign appliances were randomly selected from 10 patients before intraoral placement and after retrieval, and the prepared specimens were subjected to (1) bright-field optical reflection microscopy to study the surface morphology; (2) Fourier transform infrared microspectroscopy to characterize the in vivo changes in molecular composition induced on appliance surfaces, (3) scanning electron microscopy and energy dispersive X-ray microanalysis to identify the elemental composition of integuments formed on the surface, and (4) Vickers hardness (HV 200) testing. Another set of reference and retrieved appliances was subjected to artificial aging for 2 weeks, and the extracts were subjected to gas chromatography-mass spectroscopy. The retrieved appliances demonstrated substantial morphological variation relative to the as-received specimens involving abrasion at the cusp tips, adsorption of integuments, and localized calcification of the precipitated biofilm at stagnation sites. Buccal segments of retrieved appliances showed an increase in hardness, which might be attributed to mastication-induced cold work; however, the clinical implication of this effect on mechanotherapy is unknown. In vitro aged and retrieved appliances were found to leach no traceable amount of substances in an ethanol aging solution.