It is becoming increasingly clear that genes causing bipolar mania overlap with genes for a subtype of ADHD. The key to understanding the genetics of ADHD is to accept very considerable heterogeneity with different genes having effects in different families and in different individuals. It is too early to interpret
the new wave of genome-wide association and copy number variant studies but preliminary data support the overlap with affective disorder genes and also with CNS connectivity genes likely to be involved in autism and affective disorders. (C) 2009 Published by Elsevier Ltd.”
“Mimicry is a resemblance between species that benefits at least one of the species. It is a ubiquitous evolutionary phenomenon particularly common among prey species, in which case the advantage involves Veliparib in vitro better protection from AG-014699 nmr predation. We formulate a mathematical description of predation, to investigate benefits and disadvantages of mimicry. The basic set up involves differential equations for quantities representing predator behavior, namely, the probabilities for attacking prey at the next encounter. Using this framework, we present new quantitative results, and also provide
a unified description of a significant fraction of the quantitative mimicry literature. The new results include “”temporary” mutualism between prey species, and an optimal density at which the survival benefit is greatest for the mimic. The formalism leads naturally to extensions in several directions, such
as the interplay of mimicry with population dynamics, studies of spatiotemporal patterns, etc. We demonstrate this extensibility by presenting some explorations on spatiotemporal pattern dynamics. (C) 2009 Elsevier Barasertib in vivo Ltd. All rights reserved.”
“Attention-deficit/hyperactivity disorder (ADHD) is a neurobehavioral disorder characterized by inappropriate symptoms of inattention, impulsivity and motor restlessness. Converging data from neuropsychological, genetic, neurochemical and pharmacological studies have implicated fronto-striatal network abnormalities as the likely cause of ADHD. The functional imaging field has evolved rapidly providing unprecedented tools to examine questions regarding the pathophysiology of ADHD and the biological effects of medications used to treat it. Positron emission tomography (PET) provides unique quantitative information on the spatial resolution of radiolabelled molecules in the brain of patients or healthy subjects allowing the longitudinal assessment of physiological parameters such as binding potential over extended periods of time. The main goal of this review is to provide an overview of PET studies performed in ADHD patients, discuss their relative strengths and weaknesses and show how they can complement one another to enable a better understanding of the neurobiology and the neuropharmacology of this disease.