Resting frontal EEG asymmetry in adolescents with major depression: Impact of disease state and comorbid anxiety disorder.

Objective: Greater relative right- than left-frontal cortical activity has been frequently found in adults with major depression (MD). As the few studies in adolescents with MD have been inconclusive, the aim of this study was to assess frontal alpha asymmetry (FAA) in an adolescent sample with MD whilst taking into account possible confounding variables such as disease state and comorbid anxiety disorder.

Methods: An 8-minute resting frontal EEG was assessed in 34 healthy controls (HCs), 16 adolescents with MD in remission without comorbid anxiety disorder (rMDa-), 22 adolescents with acute depression without comorbid anxiety disorder (MDa-), and 23 adolescents with acute depression and comorbid anxiety disorder (MDa+).

Resting frontal EEG asymmetry patterns in adolescents with and without major depression.

More right-sided frontal brain resting activity has been postulated to be a correlate of major depression in adults. In children and adolescents, more right-sided activity (as indicated by more left-sided alpha activity) seems to be associated with psychosocial risk factors. However, an association of frontal asymmetry and manifest unipolar depression has not been shown in adolescents so far.

Not later, but longer: sleep, chronotype and light exposure in adolescents with remitted depression compared to healthy controls.

The relationship between sleep and adolescent depression is much discussed, but still not fully understood. One important sleep variable is self-selected sleep timing, which is also referred to as chronotype. Chronotype is mostly regulated by the circadian clock that synchronises the internal time of the body with the external light dark cycle.

[Chronotype and depression in adolescents – a review].

Many patients with depressive disorders experience symptoms in relation to sleep behavior and daily rhythmicity. However, the multifaceted associations between sleep, depression and circadian rhythms are not fully understood. During the past years, the concept of chronotypehas become increasingly popular in research.

Right-lateralization of N2-amplitudes in depressive adolescents: an emotional go/no-go study.

Background: Recent studies have proposed the process of emotion regulation as a promising target to study the neurophysiological basis of adolescent depression. Emotion regulation has repeatedly been studied with emotional go/no-go paradigms. To date, no study has examined if the left-frontal hypoactivation associated with depression generalizes to active tasks.

"Glass fairies" and "bone children": adolescents and young adults with anorexia nervosa show positive reactions towards extremely emaciated body pictures measured by the startle reflex paradigm.

In this study, we investigated the emotional processing of extremely emaciated body cues in adolescents and young adults with (n  =  36) and without (n =  36) anorexia nervosa (AN), introducing a new picture type, which was taken from websites that promote extreme thinness and is targeted specifically at adolescents interested in extreme thinness. A startle reflex paradigm was used for implicit reactions, while a self-assessment instrument was used for subjective responses. We found a significant group difference with a startle inhibition (appetitive response) among the patients and a startle potentiation (aversive response) among the controls, whereas no such difference for subjective measures was found.

Formation of the retinotectal projection requires Esrom, an ortholog of PAM (protein associated with Myc).

Visual system development is dependent on correct interpretation of cues that direct growth cone migration and axon branching. Mutations in the zebrafish esrom gene disrupt bundling and targeting of retinal axons, and also cause ectopic arborization. By positional cloning, we establish that esrom encodes a very large protein orthologous to PAM (protein associated with Myc)/Highwire/RPM-1.

Chemically controlled formation of a DNA/calcium phosphate coprecipitate: application for transfection of mature hippocampal neurons.

Numerous methods exist for transfecting postmitotic neurons, for example, DNA/calcium phosphate coprecipitation, cationic lipids, viruses, and physical methods such as microinjection, electroporation, and biolistics. Most methods, however, are either toxic to the cell, yield only poor transfection efficiencies, or cells have to be electroporated before plating. In this article, we present a standardized and fast transfection method using DNA/calcium phosphate coprecipitates that efficiently transfer DNA into mature, postmitotic hippocampal neurons.

The brain-specific double-stranded RNA-binding protein Staufen2: nucleolar accumulation and isoform-specific exportin-5-dependent export.

The mammalian double-stranded RNA-binding proteins Staufen (Stau1 and Stau2) are involved in RNA localization in polarized neurons. In contrast to the more ubiquitously expressed Stau1, Stau2 is mainly expressed in the nervous system. In Drosophila, the third double-stranded RNA-binding domain (RBD3) of Staufen is essential for RNA interaction.

EphrinB2a in the zebrafish retinotectal system.

Members of the Eph-B family of receptors tyrosine kinase and their transmembrane ligands have been implicated in dorsoventral patterning of the vertebrate retinotectal projection. In the zebrafish retinotectal system, however, ephrinB2a is expressed strongly in the posterior tectum, in tectal neurons that form physical contacts with retinal ganglion cell (RGC) axons. In the gnarled mutant, where tectal neurons form ectopically in the pretectum, RGC axons stall before entering the tectum, or else are misrouted or branch aberrantly in the tectal neuropil.

Coupling the iron-responsive element to GFP--an inducible system to study translation in a single living cell.

Local protein synthesis in a cell represents an elegant mechanism to achieve important biological phenomena such as cell migration, body axis formation during embryonic development and establishment of cell polarity. A prerequisite to studying translation in a restricted cellular compartment is the ability to unambiguously discriminate between proteins that arise through local protein synthesis and those that reach the site of interest by diffusion or transport. To tackle this problem, we set up a green fluorescent protein (GFP)-based reporter system that allows one to uncouple the translation of reporter gene mRNA from its subcellular localization.

Barentsz, a new component of the Staufen-containing ribonucleoprotein particles in mammalian cells, interacts with Staufen in an RNA-dependent manner.

Staufen1, the mammalian homolog of Drosophila Staufen, assembles into ribonucleoprotein particles (RNPs), which are thought to transport and localize RNA into dendrites of mature hippocampal neurons. We therefore investigated whether additional components of the RNA localization complex besides Staufen are conserved. One candidate is the mammalian homolog of Drosophila Barentsz (Btz), which is essential for the localization of oskar mRNA to the posterior pole of the Drosophila oocyte and is a component of the oskar RNA localization complex along with Staufen.

A GFP-based system to uncouple mRNA transport from translation in a single living neuron.

An inducible fluorescent system based on GFP is presented that allows for the uncoupling of dendritic mRNA transport from subsequent protein synthesis at the single cell level. The iron-responsive element (IRE) derived from ferritin mRNA in the 5'-UTR of the GFP reporter mRNA renders translation of its mRNA dependent on iron. The addition of the full-length 3'-UTR of the Ca(2+)/calmodulin-dependent protein kinase II alpha (CaMKIIalpha) after the stop codon of the GFP reading frame targets the reporter mRNA to dendrites of transfected fully polarized hippocampal neurons.