Normalizing the number of proliferating cells to total granule cell number, we observe an overall exponential decline in proliferation that is chronologically equal between species and orders and independent of early developmental processes and life span. Long- and short-lived mammals differ with regard to major life history stages; at the time points of weaning, age at first reproduction and average life expectancy, long-lived primates and foxes have significantly fewer proliferating cells than rodents. Although the database for neuronal differentiation

is limited, we find indications that the extent of neuronal differentiation is subject to species-specific selective adaptations. We conclude that absolute age is the critical factor S3I-201 regulating cell genesis in the adult hippocampus of mammals. Ontogenetic and ecological factors primarily GANT61 molecular weight influence the regulation of neuronal differentiation rather than the rate of cell proliferation.”
“Background: Brain-derived neurotrophic factor (BDNF) plays an important role in neural

development, and has been implicated in the development of depressive and anxiety disorders. Obsessive-compulsive disorder (OCD) is a chronic anxiety disorder with an unclear pathophysiology. Although genetic studies have suggested an association between BDNF and OCD, the results have been inconsistent. The aims of this study were to determine whether BDNF plasma levels in OCD patients are lower than those in healthy controls and whether BDNF plasma levels differ between drug-nave and drug-treated OCD patients.\n\nMethods: We examined BDNF plasma levels in 22 drug-naive OCD patients, 52 drug-treated OCD patients, and 63 healthy controls. Individuals in all groups with a current or lifetime history of depression were excluded.\n\nResults: BDNF plasma levels in both drug-nave OCD patients (1.97 +/- 1.80 ng/ml, p = 0.00) and drug-treated OCD patients (1.98 +/- 1.54 ng/ml, p = 0.00) were lower than those in normal controls (4.09 +/-

2.00 ng/ml). However BDNF plasma levels in those two OCD patients groups were not different Nutlin-3 research buy from each other significantly (p = 0.99). Length of drug treatment was positively associated with BDNF plasma levels in the drug-treated patients (r = 0.34, p = 0.03).\n\nLimitations: We used treatment length of two weeks and above as the criterion to recruit drug-treated patients. Probably this treatment length is not sufficient to identify drug-associated changes in BDNF levels.\n\nConclusions: Our findings support the hypothesis that BDNF is involved in the pathophysiology of OCD, and may be a peripheral marker indicating neurotrophic impairment in OCD. (C) 2011 Elsevier B.V. All rights reserved.”
“Functional and neuroanatomical asymmetries are an important characteristic of the human brain.