Larger deficits in brain networks for response inhibition than for visual selective attention in attention deficit hyperactivity disorder (ADHD)

BACKGROUND: Brain activation differences between 12 control and 12 attention deficit hyperactivity disorder (ADHD) children (9- to 12-year-olds) were examined on two cognitive tasks during functional magnetic resonance imaging (fMRI). METHOD: Visual selective attention was measured with the visual search of a conjunction target (red triangle) in a field of distracters and response inhibition was measured with a go/no-go task. RESULTS: There were limited group differences in the selective attention task, with control children showing significantly greater intensity of activation in a small area of the superior parietal lobule region of interest. There were large group differences in the response inhibition task, with control children showing significantly greater intensity of activation in fronto-striatal regions of interest including the inferior, middle, superior and medial frontal gyri as well as the caudate nucleus and globus pallidus. CONCLUSION: The widespread hypoactivity for the ADHD children on the go/no-go task is consistent with the hypothesis that response inhibition is a specific deficit in attention deficit hyperactivity disorder.     

Acute traumatic spinal cord injury, 1993-2000A population-based assessment of methylprednisolone administration and hospitalization

BACKGROUND: Administration of methylprednisolone sodium succinate (MPSS) after acute traumatic spinal cord injury (TSCI) is controversial. This study compared differences in acute care charge, hospital stay, and related variables as a function of MPSS receipt. METHODS: Determinants of MPSS administration were examined after acute TSCI for South Carolina patients during the period 1993 to 2000 in a multivariate logistic regression model. RESULTS: Administration of MPSS was documented for 48.7% of 1,227 randomly selected patients with TSCI. Patients admitted via trauma centers and emergency departments were more likely to receive MPSS (trama center level 1 odds ratio [OR], 4.06; 95% CI confidence interval [CI], 2.11-7.83; emergency department OR, 1.64; 95% CI, 1.20-2.23). Hospital charge and length of stay were significantly higher for MPSS recipients. CONCLUSIONS: The study findings indicate MPSS use is associated with higher acute care charges and longer hospital stays. These findings suggest the need for outcome studies to assess the long-term benefits of MPSS administration.     

Binge ethanol exposure delays development of GABAergic miniature postsynaptic currents in septal neurons

Whole cell GABA(A)R currents of septal neurons isolated from rat pups increase rapidly during the first weeks of life when inhibitory synapses are forming. Early postnatal binge ethanol intubation on days 4-9 delays this maturational up-regulation in septal neurons isolated several days later suggesting inhibitory synapse formation could be disrupted [S.-H. Hsiao, J.L. Acevedo, D.W. DuBois, K.R. Smith, J.R. West, G.D. Frye, Early postnatal ethanol intubation blunts GABA(A) receptor upregulation and modifies 3alpha-hydroxy-5alpha-pregnan-20-one sensitivity in rat MS/DB neurons, Brain Res. Dev. Brain Res. 130 (2001) 25-40]. Surprisingly, whole cell GABA(A)R function does not increase rapidly when septal neurons are grown for the same period in vitro and is not blunted by comparable ethanol exposure of the cultures [S.-H. Hsiao, D.W. DuBois, R.C. Miranda, G.D. Frye, Critically timed ethanol exposure reduces GABA(A)R function on septal neurons developing in vivo but not in vitro, Brain Res Dev. Brain Res. 1008 (2004) 69-80]. Because GABAergic miniature postsynaptic currents (mPSCs) show parallel patterns of maturation whether cortical neurons are growing in vivo or in vitro [D.D. Dunning, C.L. Hoover, I. Soltesz, M.A. Smith, D.K. ODowd, GABA(A) receptor-mediated miniature postsynaptic currents and alpha-subunit expression in developing cortical neurons, J. Neurophysiol. 82 (1999) 3286-3297], we examined the impact of binge ethanol exposure on synaptic receptors activated by these currents in septal cultures. Binge ethanol treatment of embryonic septal neurons over 6-11 days in vitro (DIV) slightly reduced GABA(A)R-mediated mPSC amplitude and frequency, but also substantially slowed decay kinetics when mPSCs were recorded later on DIV 13-18. Decreased frequency and slowed mPSC decay kinetics after ethanol were consistent with parameters measured in immature neurons. Untreated septal neurons exhibited decreased mPSC amplitude and frequency with acute 30-100 mM ethanol, without changing decay kinetics suggesting a direct inhibition of postsynaptic receptors. Sustained inhibition of GABA(A)Rs with 100 microM picrotoxin on DIV 6-11 decreased mPSC amplitude and frequency and slowed decay kinetics similar to binge ethanol exposure. These results suggest that binge ethanol exposure delays mPSC maturation by interfering with trophic postsynaptic GABA(A)R signaling during the early development of septal neurons.     

Test characteristics of a level I or II fetal ultrasound in detecting structural heart disease

At the University of California Davis Medical Center, a screening fetal ultrasound examination (level I or II) incorporates a comprehensive segmental evaluation of the fetal heart. This study evaluated the reliability of the fetal ultrasound exam in the detection of abnormal heart anatomy. Our retrospective study reviewed results of 614 antenatal patients that had a screening fetal ultrasound exam. All patients subsequently underwent a detailed targeted fetal cardiac ultrasound exam performed by a pediatric cardiac sonographer and reviewed by a board-certified pediatric cardiologist. Of these 614 patients, 60 fetuses had structural heart disease by the targeted fetal exam. The screening fetal ultrasound exam correctly identified 55 of the 60, with 5 false negatives (8.3% false-negative rate) and 1 false positive (1.7% false-positive rate). Our study suggests that if a screening fetal ultrasound exam incorporates a segmental evaluation of the fetal heart it can reliably detect abnormal heart anatomy. At our institution a targeted fetal cardiac exam is now used to confirm and provide detailed assessment of the heart anatomy when a screening fetal exam is positive for heart disease.     

Asthma in children: Management practices among paediatricians and family physicians

OBJECTIVE:

To ascertain the variation in asthma management practices among paediatricians and family physicians to determine how to improve care.

DESIGN:

Questionnaire study of paediatricians and family physicians that focused on the use of beta₂-agonists, inhaled corticosteroids, patient asthma education, quantitative measurements of airflow and diagnostic investigations for asthma. Case scenarios were used in the questionnaire.

RESULTS:

The response rate was 66% (415 of 632) among paediatricians and 42% (1156 of 2750) among family physicians. In general, both groups followed consensus guidelines. There were some differences in management practices among paediatricians and family physicians. Paediatricians were more likely to develop an action plan and less likely to use xanthines or inhaled anticholinergic agents. However, family physicians were more likely to use spirometry or home peak expiratory flow rates to make a diagnosis of asthma.

CONCLUSION:

Family physicians and paediatricians require a different focus on educational interventions to improve the care of children with asthma.