Impact of aerobic exercise training on cognitive functions and affect associated to the COMT polymorphism in young adults.

Physical fitness can serve as a means to enhance cognitive functioning by modulating particular aspects of brain functioning. However, mechanisms underlying this modulating effect remain widely unresolved. To examine the impact and to clarify the mechanisms of physical fitness training in a young and healthy population, it was investigated whether an increase in fitness would result in improvements in executive control processes and positive and negative affect. Moreover, genotype of the Val158Met polymorphism in catechol-O-methyltransferase (COMT) as an index of relative central dopamine bioavailability was determined to elucidate dopamine tuning efficiency and its association with performance in the applied cognitive tasks. Seventy-five individuals participated and underwent an incremental fitness test to assess physical fitness. An exercising group subsequently engaged in a 17 weeks running training consisting of three running sessions at moderate to high, individually adjusted intensities. Associated with increased fitness improved cognitive flexibility and cognitive control were observed, whereas working memory remained unaffected. In runners, Val/Val participants improved cognitive performance to a greater extent compared to individuals carrying a Met allele. From the present results it is concluded that an increase in physical fitness provides a means to improve cognitive functioning via dopaminergic modulation.

Aerobic endurance exercise benefits memory and affect in young adults.

Exercise seems a simple and widely practised behaviour that activates molecular and cellular signalling cascades involved in various central nervous system processes. Despite impressive results obtained in animal studies, fitness interventions have produced less reliable effects in humans, particularly in young adults. In the present study we tested the hypothesis that an individually adapted exercise training consisting of three running sessions of 30 minutes per week for 6 weeks, has the potential to improve visuospatial and verbal memory, concentration performance, and affect in young and healthy adults. Twenty-eight students participated and underwent a graded fitness test to assess individual fitness. The experimental group took part in an aerobic running programme, whereas the control group were asked not to vary their everyday activities. We found a significant increase in visuospatial memory performance and a significant increase in positive affect on a .05 alpha level of significance. However, we observed no effects of running training on concentration performance and verbal memory. We conclude that physical activity can possibly serve as a means to improve positively valenced aspects of affect and benefit visuospatial but not verbal memory in young adults.

Localization of ecdysone receptor protein during colour pattern formation in wings of the butterfly Precis coenia (Lepidoptera: Nymphalidae) and co-expression with Distal-less protein.

Butterfly wing colour patterns are determined during late larval and early pupal development, a part of metamorphosis controlled by ecdysteroid hormones via their nuclear hormone receptors. We have sequenced a fragment of the common regions of the ecdysone receptor (EcR) from the butterflies Precis coenia and Bicyclus anynanaand found high identities (83.5% to 100%) to EcR from a moth, Manduca sexta. In P. coenia, we sequenced a putative EcR-B1 isoform with 80.4% identity with the A/B-region of the M. sexta-EcR-B1. Consequently, we used antibodies generated against MsEcR-B1 to localise EcR protein during wing development of P. coenia. Nuclear staining of EcR was observed in different cell types during the course of colour pattern formation. Major observations are as follows: EcR is expressed in cell nuclei corresponding to wing lacunae and prospective veins. EcR is expressed early in pupal wing development in "focal" cells which are thought to release determining signals in a process leading to eyespot formation. Scale forming cells differentiate first and show EcR signal in the eyespot foci and most of the wing sheet, but not in areas corresponding to prospective eyespots. In the eyespots, 20-24 h after pupation, EcR expression seems to play a role in formation of scale rows preceding a later expression (28 h) in scale-forming cells. The results demonstrate that EcR is locally expressed in correlation to all major events of wing development and colour pattern formation. In particular, EcR expression patterns in prospective eyespots show that these are special pattern elements which are specified in concert with other factors of colour pattern formation such as the transcription factor Distal-less. In eyespot foci, Distal-less is expressed simultaneously with EcR, but clearly precedes EcR expression in eyespot scale-forming cells. This indicates a potential interaction between "short-range" signalling systems and "long-range" hormonal systems.

Metal vs ligand reduction in complexes of dipyrido[3,2-a:2',3'-c]phenazine and related ligands with [(C5Me5)ClM]+ (M = Rh or Ir): evidence for potential rather than orbital control in the reductive cleavage of the metal-chloride bond.

Complexes between the chlorometal(III) cations [(C5Me5)ClM]+, M = Rh or Ir, and the 1,10-phenanthroline-derived alpha-diimine (N--N) ligands dipyrido[3,2-a:2',3'-c]phenazine (dppz), 1,4,7,10-tetraazaphenanthrene (tap), or 1,10-phenanthroline-5,6-dione (pdo) were investigated by cyclic voltammetry, EPR, and UV-vis-NIR spectroelectrochemistry with respect to either ligand-based or metal-centered (and then chloride-dissociative) reduction. Two low-lying unoccupied molecular orbitals (MOs) are present in each of these three N wedge N ligands; however, their different energies and interface properties are responsible for different results. Metal-centered chloride-releasing reduction was observed for complexes of the DNA-intercalation ligands dppz and tap to yield compounds [(N--N)(C5Me5)M] in a two-electron step. The separation of alpha-diimine centered optical orbitals and phenazine-based redox orbitals is apparent from the EPR and UV-vis-NIR spectroelectrochemistry of [(dppz)(C5Me5)M](0/*-/2-). In contrast, the pdo complexes undergo a reversible one-electron reduction to yield o-semiquinone radical complexes [(pdo)(C5Me5)ClM]* before releasing the chloride after the second electron uptake. The fact that the dppz complexes undergo a Cl(-)-dissociative two-electron reduction despite the presence of a lowest lying pi* MO (b1(phz)) with very little overlap to the metal suggests that an unoccupied metal/chloride-based orbital is lower in energy. This assertion is confirmed both by the half-wave reduction potentials of the ligands (tap, -1.95 V; dppz, -1.60 V; pdo, -0.85 V) and by the typical reduction peak potentials of the complexes [(L)(C5Me5)ClM](PF6) (tap, -1.1 V; dppz, -1.3 V; pdo, -0.6 V; all values against Fc(+/0)).

Ultrasensitive detection of unstained proteins in acrylamide gels by native UV fluorescence.

Visualization of proteins inside acrylamide and other gels usually relies on different staining methods. To omit the protein-staining procedure, we visualized unstained proteins inside acrylamide gels by laser excitation with ultraviolet (UV) light (280 nm, 35 mJ/cm2) and directly detected native UV fluorescence. In one-dimensional gels, a detection limit as low as 1 ng for bovine serum albumin and 5 ng for other proteins with a linear dynamic range (2.7 orders of magnitude) comparable to state of the art fluorescent dyes could be achieved. In addition, the application of this method to 20 microg of a whole cell lysate separated in a two-dimensional gel showed more than 600 spots. Since protein labeling always represents a serious obstacle in protein identification technologies, the working efficiency with our procedure can be considered as a significant improvement for protein visualization and reproducibility in proteomics.