Antidepressants and psychostimulants in pediatric populations: is there an association with mania?

This article reviews the literature that examines whether exposure to psychostimulants or antidepressants precipitates or exacerbates manic symptoms, or decreases the age at onset of mania in pediatric populations. A PubMed search using relevant key words identified studies targeting five distinct clinical groups: (i) youth without a diagnosis of bipolar disorder (BD) at the time of exposure to psychostimulants; (ii) youth with a diagnosis of BD at the time of exposure to psychostimulants; (iii) youth without a diagnosis of BD at the time of exposure to antidepressants; (iv) youth with a diagnosis of BD at the time of exposure to antidepressants; and (v) youth who develop BD after exposure to these medications. In patients with attention-deficit hyperactivity disorder (ADHD), the risk for mania was found to be relatively low with the use of psychostimulants. For patients with BD and ADHD, effective mood stabilization is important prior to adding a stimulant. For children with depression and/or anxiety, the risk of antidepressant-induced mania (AIM) was generally low (<2%), but the risk of general 'activation' secondary to a selective serotonin reuptake inhibitor (SSRI) may be greater (2-10%). However, rates of AIM in specialty clinics appear to be much higher. SSRIs may be particularly problematic in specific populations, such as those with some symptoms of mania or a family history of BD, but the precise risk is unknown. There is no clear evidence that stimulants or SSRIs accelerate the natural course of BD development in overall samples, but in individual cases prescribers should proceed cautiously when using these agents in youth already at risk for developing BD, such as those with ADHD and mood dysregulation, a history of prior AIM, a history of psychosis, or a family history of BD.

Mitochondrial DNA phylogeography of western lowland gorillas (Gorilla gorilla gorilla).

The geographical distribution of genetic variation within western lowland gorillas (Gorilla gorilla gorilla) was examined to clarify the population genetic structure and recent evolutionary history of this group. DNA was amplified from shed hair collected from sites across the range of the three traditionally recognized gorilla subspecies: western lowland (G. g. gorilla), eastern lowland (G. g. graueri) and mountain (G. g. beringei) gorillas. Nucleotide sequence variation was examined in the first hypervariable domain of the mitochondrial control region and was much higher in western lowland gorillas than in either of the other two subspecies. In addition to recapitulating the major evolutionary split between eastern and western lowland gorillas, phylogenetic analysis indicates a phylogeographical division within western lowland gorillas, one haplogroup comprising gorilla populations from eastern Nigeria through to southeast Cameroon and a second comprising all other western lowland gorillas. Within this second haplogroup, haplotypes appear to be partitioned geographically into three subgroups: (i) Equatorial Guinea, (ii) Central African Republic, and (iii) Gabon and adjacent Congo. There is also evidence of limited haplotype admixture in northeastern Gabon and southeast Cameroon. The phylogeographical patterns are broadly consistent with those predicted by current Pleistocene refuge hypotheses for the region and suggest that historical events have played an important role in shaping the population structure of this subspecies.