Reactivity and regulation in children prenatally exposed to cocaine.

Children prenatally exposed to cocaine may be at elevated risk for adjustment problems in early development because of greater reactivity and reduced regulation during challenging tasks. Few studies have examined whether cocaine-exposed children show such difficulties during the preschool years, a period marked by increased social and cognitive demands and by rapid changes in reactivity and regulation. The authors addressed this question by examining frustration reactivity and regulation of behavior during a problem-solving task in cocaine-exposed and -unexposed preschoolers. Participants were 174 4.5-year-olds (M age = 4.55 years, SD = 0.09). Frustration reactivity was measured as latency to show frustration and number of disruptive behaviors, whereas regulation was measured as latency to approach and attempt the problem-solving task and number of problem-solving behaviors. Results indicated that cocaine-exposed children took longer to attempt the problem-solving task but that cocaine-exposed boys showed the most difficulties: They were quicker to express frustration and were more disruptive. Effect sizes were relatively small, suggesting both resilience and vulnerabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Semantic development of African-American children prenatally exposed to cocaine

Semantic content categories were described for the single word, multiple word, and verb relation utterances of 22 African-American 2-year-olds during a 90-min laboratory session. Half of the toddlers had been exposed prenatally to cocaine and half were unexposed, as documented by biological assay in the newborn period. The exposed and unexposed groups were carefully matched on demographic, medical, and proximal caregiving variables. Children's spontaneous utterances were transcribed from audio- and videotapes during the laboratory session and scored for semantic features by a team of reliable coders who were masked to child exposure status. General productive language features (utterance length, verbosity, and intelligibility) were also assessed. To evaluate general language and cognitive skills, the toddlers were evaluated with the Sequenced Inventory of Communicative Development-Revised (SICD-R) and the Bayley Scales of Infant Development (BSID). Although exposed and nonexposed toddlers exhibited similar sequences of semantic development, the exposed toddlers were more restricted and delayed in their semantic representations. No significant group differences were observed, however, for structural features of language (e.g., utterance length, distribution of utterance types) or for children's general language and cognitive functioning as assessed by standardized assessments (i.e., SICD-R, BSID). Thus, a history of prenatal cocaine exposure and associated risk factors (e.g., prenatal exposure to alcohol, diminished birth weight) are related to delays in early semantic development. Proposed diagnostic and treatment strategies are discussed.     

Specific impairments in self-regulation in children exposed to alcohol prenatally

The present study utilizes a conceptual framework derived from theories of cognition to explain the pattern of behavioral and learning problems observed in subjects with fetal alcohol syndrome (FAS) and fetal alcohol effects (FAE). Based on a modern interpretation of Luria's theory of self-regulation, this study used a neuropsychological test battery to compare 10 subjects (mean age = 13 years) having FAS/FAE with 10 control subjects (mean age = 12 years and 9 months). Subjects with FAS/FAE were relatively high functioning and did not significantly differ from controls with respect to receptive vocabulary. However, those with FAS/FAE exhibited greater difficulty than controls on tasks that involved the manipulation of information and goal management in working memory (e.g., Planning, Controlled Oral Word Association, etc). Both groups performed equally well on some tasks that demanded rule learning (Delayed Response) and response inhibition (Go-No-Go). The above impairments were interpreted to be reflective of selective rather than generalized disruptions of neural networks that subserve working memory.     

Modifications of thalamo-cortical circuitry in rats prenatally exposed to ethanol

The present study aimed to investigate the organization of thalamo-cortical connections in adult rats exposed to ethanol during the last week of foetal life. Animals underwent thalamic injections of lectin-conjugated HRP. Results demonstrate that the thalamic-recipient zone of sensorimotor cortex is significantly thinner in ethanol-exposed than in control cases. Animals exposed to ethanol also display aberrant thalamo-cortical terminations in layer 5a. Neurones of origin of cortico-thalamic projections are normally located in layers 5 and 6; they appear quantitatively comparable in control and ethanol-exposed cases. Developmental alterations underlying the establishment of anomalous thalamo-cortical relationships are discussed.     

Object-recognition and spatial learning and memory in rats prenatally exposed to ethanol.

Prenatal ethanol exposure can produce cognitive and behavioral impairments. In the present study, rats from prenatal ethanol (E), pair-fed (PF), and ad libitum-fed control (C) treatment conditions were tested on the object-recognition delayed-nonmatching-to-sample (DNMS) task with nonrecurring items and on the spatial-navigation Morris water maze task. In Experiment 1, there were no significant differences among groups in object-recognition learning and memory, distractibility, or response perseveration on the DNMS task. In Experiment 2, the same rats were tested in the water maze; E rats took significantly longer to learn the task than did the PF or C rats. These data suggest that the mechanisms underlying spatial cognitive abilities are more vulnerable to the teratogenic effects of prenatal ethanol exposure than those underlying object-recognition abilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Blood pressure normal values in children and adolescents according to age and height

The assessment of blood pressure in children and adolescents is of great importance in order to gain a better understanding of its pattern of evolution. The authors publish the normal values of blood pressure in Portuguese children and adolescents, according to age and sex, as well as the mean values of the 90th percentile, which are very important to separate normal children from those with high blood pressure. In this study the fifth Korotkoof sound is used to define diastolic blood pressure in all ages. New blood pressure tables are also published, for children and adolescents, that now include the height percentile for age and blood pressure. These new charts have been developed to guide practising clinicians in antihypertensive drug therapy, when indicated.     

Evidence for increased seizure susceptibility in rats exposed to cocaine in utero

The effect of (+)-5-oxo-D-prolinepiperidinamide monohydrate (NS-105), a novel cognition enhancer, on adenylate cyclase activity was investigated in cultured neurons of the mouse cerebral cortex. NS-105 (10(-7) and 10(-6) M) inhibited forskolin-stimulated cyclic AMP formation, an action that was dependent on pertussis toxin-sensitive G proteins. Conversely, in pertussis toxin-pretreated neurons, NS-105 (10(-7)-10(-5) M) significantly enhanced the forskolin-stimulated cyclic AMP formation, and this action was completely reversed by cholera toxin. A metabotropic glutamate receptor agonist (1S, 3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S, 3R-ACPD) produced similar bi-directional actions on the cyclic AMP formation. Both of these inhibitory and facilitatory actions of NS-105 and 1S, 3R-ACPD were blocked by L(+)-2-amino-3-phosphopropinoic acid (L-AP3). NS-105 (10(-6) M) and 1S, 3R-ACPD (10(-4) M) significantly enhanced isoproterenol- and adenosine-stimulated cyclic AMP formation. The enhancement of such Gs-coupled receptor agonists-stimulated cyclic AMP formation was also produced by quisqualate but not by L(+)-2-amino-4-phosphonobutanoate (L-AP4). The phosphoinositides hydrolysis was enhanced by 1S, 3R-ACPD (10(-4) M) but not by NS-105 (10(-6) M), however, 1S, 3R-ACPD-induced increase in phosphoinositides turnover was attenuated by NS-105. These findings suggest that NS-105 stimulates metabotropic glutamate receptor subclasses that are coupled both negatively and positively to adenylate cyclase, but it acts as an antagonist at the receptor subclasses that are linked to phosphoinositides hydrolysis.     

Adult reactivity in rats exposed to cocaine during two early postnatal periods

The effects of temperature on the A-B transition of DNA in fibers are determined by fiber X-ray diffraction and measurement of variations of the fiber length with the relative humidity (r.h.). It is observed that the transition from the A to the B helical form occurs at higher r.h. when the temperature is raised. At 7 degrees C, this transition is complete for a r.h. of 88% while the A form remains stable at that same r.h. and is even maintained for r.h. values up to 92% when the temperature is 37 degrees C. The interpretation of the present experimental results is given in terms of hydration effects in which the entropic contribution of the solvent molecules is dominant.     

Blood pressure responses to cold pressor stress and its relation to sodium metabolism in salt-sensitive children

OBJECTIVE: To investigate the blood pressure responses to cold pressor stress and its relation to sodium metabolism in salt-sensitive children. METHOD: 268 children aged 10.6 +/- 1.1 years were detected salt-sensitivity with the tests of oral saline load and furosemde sodium-volume depletion. Cold pressor stress test, sodium metabolism, and the related factors were measured. RESULTS: 25% of the children were detected to be salt-sensitive. The increased extent of blood pressure and its recovery time from peak to baseline in salt-sensitive children were significantly higher than those in non-salt-sensitive children during the cold pressor stress test (t = 5.14, 3.94, P < 0.01 and t = 2.16, P < 0.05). The increased extent of blood pressure and its recovery time during cold pressor test were correlated positively with red-cell sodium content, and were correlated negatively with 2 hour urinary sodium excreation during the oral saline load test. CONCLUSION: Children with salt-sensitivity have a remarkably increased blood pressure responses to cold pressor stress (sympathetic activity), which is related with abnormal sodium metabolism.     

Differential effects on cognitive functioning in 9- to 12-year olds prenatally exposed to cigarettes and marihuana

Cognitive performance was examined in 131 9-12-year-old children for whom prenatal marihuana and cigarette exposure had been ascertained. The subjects, participants in an ongoing longitudinal study, were from a low-risk, predominantly middle class sample. The tasks included the WISC-III and a series of tests assessing aspects of cognition subsumed under the rubric of executive function. Consistent with results obtained at earlier ages, discriminant function analysis revealed a dose-dependent association, which remained after controlling for potential confounds (including secondhand smoke), between prenatal cigarette exposure and lower global intelligence scores with the verbal subtests of the WISC maximally discriminating among levels of in utero exposure. In contrast, prenatal marihuana exposure was not associated with global intelligence or the verbal subtests. Rather, this drug was negatively associated with the executive function tasks that require impulse control and visual analysis/hypothesis testing and with a number of WISC subtests requiring the same abilities. The interpretation of these results is discussed in terms of executive function and is related to earlier observations of this sample and to the extant prefrontal and general marihuana literature.     

Intellectual impairment in children exposed to polychlorinated biphenyls in utero

BACKGROUND: In utero exposure to polychlorinated biphenyls, a ubiquitous environmental contaminant, has been linked to adverse effects on neurologic and intellectual function in infants and young children. We assessed whether these effects persist through school age and examined their importance in the acquisition of reading and arithmetic skills. METHODS: We tested 212 children, recruited as newborns to overrepresent infants born to women who had eaten Lake Michigan fish contaminated with polychlorinated biphenyls. A battery of IQ and achievement tests was administered when the children were 11 years of age. Concentrations of polychlorinated biphenyls in maternal serum and milk at delivery were slightly higher than in the general population. A composite measure of prenatal exposure was derived from concentrations in umbilical-cord serum and maternal serum and milk. RESULTS: Prenatal exposure to polychlorinated biphenyls was associated with lower full-scale and verbal IQ scores after control for potential confounding variables such as socioeconomic status (P = 0.02). The strongest effects related to memory and attention. The most highly exposed children were three times as likely to have low average IQ scores (P <0.001) and twice as likely to be at least two years behind in reading comprehension (P = 0.03). Although larger quantities of polychlorinated biphenyls are transferred by breast-feeding than in utero, there were deficits only in associated with transplacental exposure, suggesting that the developing fetal brain is particularly sensitive to these compounds. CONCLUSIONS: In utero exposure to polychlorinated biphenyls in concentrations slightly higher than those in the general population can have a long-term impact on intellectual function.     

Mental capability of children exposed to lead pollution

'Eleven-plus' school examination scores were obtained for 851 Birmingham children residing since birth in a lead-polluted area and 1642 children residing in two similar but unpolluted areas. It was found that the children in the lead-polluted area actually scored higher on the average than children in the control areas. Within the area of lead contamination, children living closest to the source of pollution did not have significantly lower scores than children living further away. The results indicate that lead pollution of the magnitude reported in this investigation did not have a demonstrable effect on the mental capabilities of children in the affected community.     

Changes in the retinal ganglion cell layer and optic nerve of rats exposed neonatally to cocaine

In a study of 452 ex-prisoners in England in 1990, 66 people reported that they were tested for HIV antibodies when last in prison. The circumstances under which many of those who were tested were difficult: 36% found it an unpleasant experience, 17% had not taken the test voluntarily and 55% said they received no counselling. Further information was gathered about the experiences of those who were HIV positive or assumed to be. Most were accommodated in a 'special location', not allowed to associate with other prisoners and denied access to work or recreational facilities. These data highlight the difficulties arising from the policy of Viral Infectivity Restrictions, a set of regulations applied to the management of prisoners with HIV in English prisons. This policy created a distressing situation for those tested for HIV or identified as being HIV positive in prison. For the prison environment, these conditions may create a vicious circle reinforcing inaccurate beliefs and anxieties.     

Stress in children exposed to violence. Reenactment and rage

Violence is a major public health problem that increasingly involves children and adolescents as both victims and witnesses. Exposure to violence is now implicated in the development of stress conditions. This article uses Terr's typology to describe responses to various kinds of violence and suggests that the posttraumatic stress model adds a unique dimension to our understanding of the effects of violence on children and adolescents.     

Blood pressure tracking

Interactions between nitric oxide (NO) and angiotensin (ANG) II in renal vascular beds were examined in anesthetized dogs. The renal blood flow (RBF) response to an intrarenal arterial injection of ANG II was significantly augmented by intrarenal infusion of the NO synthase inhibitor N(G)-nitro-L-arginine (LNA, 50 microg/kg/min). The simultaneous intrarenal infusion of L-arginine (1 mg/kg/min) prevented the potentiating action of LNA. Similar potentiation was also seen in phenylephrine-induced renal vasoconstriction. Moreover, during simultaneous intrarenal infusion of sodium nitroprusside (SNP), an NO donor, the potentiating action of LNA on the renal vasoconstrictor action of ANG II disappeared. Under these conditions, the released NO stimulated by ANG II was still inhibited by LNA, if present, but basally released NO was resupplied by SNP, as indicated by the return of the RBF. During an infusion of phenylephrine, which produced an increase in renal vascular tone similar to that observed during the infusion of LNA, the renal vasoconstrictor action of ANG II was not augmented. These data suggest that basally released NO plays an important role in the regulation of renal hemodynamics by modulating the renal vasoconstrictor actions of ANG II and phenylephrine.     

Detection of cocaine exposure in the neonate. Analyses of urine, meconium, and amniotic fluid from mothers and infants exposed to cocaine

Cocaine and its metabolites were measured in urine, meconium, and amniotic fluid specimens collected from 30 maternal-infant pairs with histories of prenatal cocaine use. Cocaine, benzoylecgonine, and ecgonine methyl ester were measured by isotope dilution gas chromatography-mass spectrometry. Mothers were interviewed at delivery regarding their cocaine use during pregnancy. There was qualitative agreement between the results of drug determinations in maternal urine, amniotic fluid, infant urine, and meconium. Although all of the mothers in this study admitted to using cocaine during their pregnancy, cocaine or its metabolites were detected only in the 20 cases in which cocaine was used within 3 weeks before delivery. We conclude that when sufficiently sensitive analytic methods are used, maternal urine, infant urine, and meconium analyses yield equivalent results for detection of prenatal cocaine exposure. Importantly, neither meconium nor urinary drug measurements detected cocaine exposure when the last reported use was prior to 3 weeks before delivery.