These findings provide fresh evidence for abnormalities in the striatum of medication-naïve pediatric MDD patients and suggest the possible involvement of the striatum in the pathophysiology of MDD.

Obsessive-compulsive disorder (OCD) has been associated with regional volumetric brain abnormalities, which provide promising intermediate phenotypes of the disorder. In this study, volumes of brain regions selected for a priori evidence of association with OCD (orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), thalamus, caudate, putamen, globus pallidus and pituitary) were measured using structural magnetic resonance imaging (MRI) in 20 psychotropic-naïve pediatric OCD patients. We examined the association between these regional brain volumes and a total of 519 single nucleotide polymorphisms (SNPs) from nine glutamatergic candidate genes (DLGAP1, DLGAP2, DLGAP3, GRIN2B, SLC1A1, GRIK2, GRIK3, SLITRK1 and SLITRK5). These genes were selected based on either previous reported association with OCD in humans or evidence from animal models of OCD. After correcting for multiple comparisons by permutation testing, no SNP remained significantly associated with volumetric changes. The strongest trend toward association was identified between two SNPs in DLGAP2 (rs6558484 and rs7014992) and OFC white matter volume (P = 0.000565, Padjusted= 0.3071). Our other top ranked association findings were with ACC, OFC and thalamus. These preliminary results suggest that sequence variants in glutamate candidate genes may be associated with structural neuroimaging phenotypes of OCD.

Objective: The aim of this study was to assess the effectiveness and tolerability of a long-acting methylphenidate (MPH) formulation, beaded MPH (B-MPH), for treatment of attention-deficit=hyperactivity disorder (ADHD) in 4-and 5-year-old children. Global Impressions-Severity (CGI-S) scale showed a statistically significant improvement from a baseline mean of 5 to the final visit mean of 3.36 ( p < 0.01). At the final visit, the mean daily B-MPH dose was 17.73 mg. Subjects did not experience any statistically significant changes in weight, blood pressure, or pulse during the study. The most common adverse event was decreased appetite. Conclusion: B-MPH was safe and effective for the treatment of ADHD in the 4-and 5-year-olds participating in this study.

The lack of OFC volume abnormalities in pediatric MDD patients suggests the abnormalities previously reported for adults may develop later in life as a result of neural cell loss.