Subanesthetic ketamine infusions for suicide ideation in patients with bipolar and unipolar treatment refractory depression.

We evaluated the effects of repeated subanesthetic ketamine infusions on suicidal ideation (SI) in patients with major depression. 82 subjects with treatment-resistant unipolar and bipolar depression completed a two-site open-label case-series of repeated (up to four weeks) infusions of ketamine (0.5 mg/kg). Ketamine produced a significant reduction in SI as early as one hour (71.1%) and up to 1-week post-infusion (60.4%), accompanied by a reduction in overall depressive symptoms which were maintained until the 4th week. The observed anti-suicidal effect was independent of mood changes, as patients whose mood did not respond still exhibited significantly less SI than baseline.

Changes over time in the spatiotemporal dynamics of cyclic populations of field voles (Microtus agrestis L.).

We demonstrate changes over time in the spatial and temporal dynamics of an herbivorous small rodent by analyzing time series of population densities obtained at 21 locations on clear cuts within a coniferous forest in Britain from 1984 to 2004. Changes had taken place in the amplitude, periodicity, and synchrony of cycles and density-dependent feedback on population growth rates. Evidence for the presence of a unidirectional traveling wave in rodent abundance was strong near the beginning of the study but had disappeared near the end. This study provides empirical support for the hypothesis that the temporal (such as delayed density dependence structure) and spatial (such as traveling waves) dynamics of cyclic populations are closely linked. The changes in dynamics were markedly season specific, and changes in overwintering dynamics were most pronounced. Climatic changes, resulting in a less seasonal environment with shorter winters near the end of the study, are likely to have caused the changes in vole dynamics. Similar changes in rodent dynamics and the climate as reported from Fennoscandia indicate the involvement of large-scale climatic variables.

Male gender promotes an increased inflammatory response to lipopolysaccharide in umbilical vein blood.

OBJECTIVES: To establish gender-specific differences in maternal and fetal immune response in healthy human fetuses at term. METHODS: Forty-five women with elective caesarean sections for uncomplicated singleton pregnancies were recruited for two studies. Using a multiplex biomarker immunoassay system, unstimulated maternal and fetal plasma concentrations of interleukin (IL)-1ß, IL-1ra, IL-6, IL-8, macrophage inflammatory protein (MIP)-1α, and tumor necrosis factor (TNF)-α were measured from one study population. Lipopolysaccharide (LPS)-stimulated cytokine response was measured in a second study. RESULTS: There were no significant gender differences in either maternal or fetal unstimulated plasma cytokine concentrations, but concentrations of the proinflammatory cytokines IL-1ß and IL-6 were significantly greater in male fetal LPS-stimulated samples than in female fetal samples. CONCLUSIONS: Blood of male fetuses mounts a larger pro-inflammatory response to lipopolysaccharide (LPS). This heightened response could be a critical pathway in promoting premature rupture of membranes (PPROM) and may be associated with life long differential gender response to infection.