A comparison of blue crab and bivalve delta15N tissue enrichment in two North Carolina estuaries.

Stable isotope analyses (delta(15)N) were used to examine invertebrate tissue enrichment in two North Carolina estuaries with differing amounts of nutrient loading. Bivalves collected from a nutrient sensitive estuary yielded a significant difference in mean nitrogen isotopic composition of tissue (10.4 per thousand+/-0.82; N=66) compared to bivalves collected from a less nutrient sensitive estuary (6.4 per thousand+/-0.63; N=45). Similarly, blue crabs from nutrient sensitive sites had a nitrogen isotopic composition of 11.4 per thousand (+/-1.3, N=77), which was significantly different (P<0.001) than the tissue of less nutrient sensitive blue crabs (9.6 per thousand+/-0.6; N=77). The results showed that an inverse relationship exists between invertebrate tissue enrichment and indicators of water quality across estuarine sites. This study suggests that a relationship may exist between nutrient sources and subsequent energy transfer to estuarine consumers in two North Carolina estuaries.

Effect size of lithium, divalproex sodium, and carbamazepine in children and adolescents with bipolar disorder.

OBJECTIVE: To develop effect sizes for 3 mood stabilizers--lithium, divalproex sodium, and carbamazepine--for the acute-phase treatment of bipolar I or II disorder, mixed or manic episode, in children and adolescents aged 8 to 18 years. METHOD: Forty-two outpatients with a mean age of 11.4 years (20 with bipolar I disorder and 22 with bipolar II disorder) were randomly assigned to 6 weeks of open treatment with either lithium, divalproex sodium, or carbamazepine. The primary efficacy measures were the weekly Clinical Global Impression Improvement scores and the Young Mania Rating Scale (Y-MRS). RESULTS: Using a > or = 50% change from baseline to exit in the Y-MRS scores to define response, the effect size was 1.63 for divalproex sodium, 1.06 for lithium, and 1.00 for carbamazepine. Using this same response measure with the intent-to-treat sample, the response rates were as follows: sodium divalproex, 53%; lithium, 38%; and carbamazepine, 38% (chi 2(2) = 0.85, p = .60). All 3 mood stabilizers were well tolerated, and no serious adverse effects were seen. CONCLUSIONS: Divalproex sodium, lithium, and carbamazepine all showed a large effect size in the open treatment of children and adolescents with bipolar I or II disorder in a mixed or manic episode.

Mood stabilizers and anticonvulsants.

This article provides pediatricians and other clinicians who treat children and adolescents with a working knowledge of mood stabilizers and their potential uses in children and adolescents with mood and behavior disorders. Mood stabilizers are ubiquitous agents that are often effective in the treatment of children and adolescents with bipolar disorders or conduct disorders and mentally retarded patients with aggressive behavior. The authors' also discuss mechanisms of action, pharmacokinetics, dosing, drug interactions, and potential uses. Following these medication details, specific information concerning the diagnosis and treatment of several child and adolescent mood and behavior disorders, and in which treatment with mood stabilizers may be helpful, is presented.

Sertraline treatment of transition-associated anxiety and agitation in children with autistic disorder.

The intolerance of children with autistic disorder to changes in their routine or environment is well known, typically presenting with acute symptoms of anxiety, panic, irritability, or agitation. In a clinical sample of children (6-12 years old) with autistic disorder and transition-induced behavioral deterioration, 8 of 9 patients showed a clinically significant improvement in response to sertraline treatment. Only one child was taking concurrent psychotropic medication. Therapeutic doses were surprisingly low in all cases (25-50 mg daily), with a clinical response appearing generally in 2-8 weeks. Adverse effects were minimal (one child developed stomachaches), except for apparent sertraline-induced behavioral worsening in 2 children when their doses were raised to 75 mg daily. In 3 children, an initial satisfactory clinical response appeared to diminish after 3-7 months of treatment, despite steady or increased doses. In 6 patients, the beneficial effects persisted throughout the several-month follow-up period. Only four of the children's families were identified as having mood and/or anxiety disorders. This open-label study suggests that short-term sertraline treatment may reduce the behavioral reactions seen in association with situational transitions or environmental changes in children with autistic disorder, though the beneficial effect may be only temporary in some children. Our experience suggests that small doses of sertraline may be effective and that some children may require divided doses of sertraline during the day. Controlled studies are needed to determine the efficacy, safety, and pharmacokinetics of sertraline in treating this "need for sameness," both in short-term and long-term studies of children with autistic disorder.

Structural abnormalities in brain magnetic resonance images of depressed children.

OBJECTIVE: Brain magnetic resonance images (MRIs) of 65 children and adolescents who were hospitalized with depressive disorders (DD) were compared with the brain MRIs of 18 hospitalized psychiatric controls (PC) without a depressive disorder. METHOD: Volumetric analyses were used to measure frontal lobe volumes (FLV), lateral ventricular volumes (VV), and total cerebral volumes (CV) for all subjects. To correct for differences in absolute cerebral volume associated with different body and head size, the ratios of FLV/CV and VV/CV were used to compare differences between the two groups. A multivariate analysis was used to control for the effects of several independent variables (age, sex, diagnosis). RESULTS: Significant differences were seen in the FLV/CV ratio and the VV/CV ratio when the results were compared between the two groups (DD versus PC). The DD group had a significantly smaller FLV/CV ratio (t = 2.148, df = 79, p = .035) and a significantly larger VV/CV ratio (t = -2.093, df = 79, p = .040). CONCLUSION: The findings are consistent with previous reports in depressed adults and may implicate the frontal lobes in the pathogenesis of early-onset depressive disorders.

Current perspectives on the pharmacotherapy of depressive disorders in children and adolescents.

Major depressive disorder occurs in approximately 2% of prepubertal children and 5% of adolescents. Studies investigating the pharmacotherapy of early-onset major depressive disorder in these young patients have been inconclusive. Early open trials and anecdotal experience suggested a beneficial role for antidepressant therapy. Double-blind placebo-controlled trials have failed to demonstrate the robust response seen in adults, but the studies have been small and concerns have been raised regarding methodology. Nevertheless, the significant morbidity associated with depressive disorders and the positive open trial experiences with antidepressants have led to the recommendation that antidepressants be used early in life when a patient presents with symptoms of a depressive disorder and has significant functional incapacity because of these symptoms. This article will review the studies of antidepressant efficacy in juvenile-onset major depressive disorder and then propose a pharmacotherapy model.