Molekulardynamische Simulationen von Wirt-Gast-Komplexen

Durch Molekulardynamische Simulationsläufe über jeweils 1000 ps werden Struktur, Dynamik und Komplexierungsverhalten von p-Sulfonato-Calix[4]aren 5- als Wirtmolekül mit 6 verschiedenen kationischen Gastmolekülen in Wasser temperaturabhängig untersucht. Das Simulationsprogramm moscito vermag zusammen mit dem verwendeten SPC/E Wassermodell sowohl die Ergebnisse anderer Simulationen als auch experimentelle Werte zu reproduzieren. Die aus den mittleren quadratischen Verschiebungen der Massenschwerpunkte ermittelten Translationsselbstdiffusionskoeffizienten der Wirt - Gast Komplexe erweisen sich als relativ unabhängig vom Gastmolekül. Die durch Umorientierungskorrelationsfunktionen von molekülfesten Achsensystemen ermittelten Reorientierungszeiten der Wirt - Gast Komplexe sind aufgrund der im Vergleich zum realen Wasser geringeren Viskosität von SPC/E-Wasser und der höheren Calixarenkonzentration im Vergleichsexperiment kürzer als im Experiment. Die Hydratation der Gastmoleküle, des Wirtmoleküls und der Wirt - Gast Komplexe wird wie die Orientierung der Gäste im Wirtmolekül durch Paarverteilungsfunktionen, Winkelverteilungen, Torsionswinkelverteilungen und Scatterplots bestimmt. Die Partialladungsverteilung des Calixarens erweist sich als wichtigste Einflussgröße für alle bestimmten Eigenschaften.By molecular dynamics simulation runs over 1000 ps the structure, dynamics and complexation behaviour of the host molecule p-Sulfonato-Calix[4]aren 5- with six different cationic guest molecules in water, are determined over a wide temperature range. The employed simulation program moscito, together with the SPC/E water modell, is able to reproduce experimental results as well as other simulation results. The translational self-diffusion coefficients of the host-guest complexes, determined by the mean square displacements of the center of mass of the molecule, are quite independent of the guest molecule. The reorientational times of the host-guest complexes, determined by reorientational correlation functions of molecular axis systems, are shorter than in the experiment. This is due to the lower viscosity of SPC/E water compared to real water and the higher concentration of the calixaren in the experiment. The hydration of the guests, the hosts and the host-guest complexes as well as the orientation of the guests in the host molecule are determined by pair distribution functions, angle distributions, dihedral angle distributions and scatter plots. The distribution of the partial charges on the calixaren has the strongest influence on the determined properties

A pilot study of hair and cytokine balance alteration in healthy young women under major exam stress

Mouse models show that experimental stress mimicking prolonged life-stress exposure enhances neurogenic inflammation, induces adaptive immunity cytokine- imbalance characterized by a shift to Type 1 T-helper cell cytokines and increases apoptosis of epithelial cells. This affects hair growth in otherwise healthy animals. In this study, we investigate whether a prolonged naturalistic life-stress exposure affects cytokine balance and hair parameters in healthy humans. 33 (18 exam, 15 comparison) female medical students with comparable sociobiological status were analyzed during a stressful final examination period, at three points in time (T) 12 weeks apart. T1 was before start of the learning period, T2 between the three-day written exam and an oral examination, and T3 after a 12 week rest and recovery from the stress of the examination period. Assessments included: self-reported distress and coping strategies (Perceived Stress Questionnaire [PSQ], Trier Inventory for the Assessment of Chronic Stress [TICS]), COPE), cytokines in supernatants of stimulated peripheral blood mononucleocytes (PBMCs), and trichogram (hair cycle and pigmentation analysis). Comparison between students participating in the final medical exam at T2 and non-exam students, revealed significantly higher stress perception in exam students. Time-wise comparison revealed that stress level, TH1/TH2 cytokine balance and hair parameters changed significantly from T1 to T2 in the exam group, but not the control. However, no group differences were found for cytokine balance or hair parameters at T2. The study concludes that in humans, naturalistic stress, as perceived during participation in a major medical exam, has the potential to shift the immune response to TH1 and transiently hamper hair growth, but these changes stay within a physiological range. Findings are instructive for patients suffering from hair loss in times of high stress. Replication in larger and more diverse sample populations is required, to assess suitability of trichogram analysis as biological outcome for stress studies

Fine mapping and cloning of the major seed protein quantitative trait loci on soybean chromosome 20

Soybean [Glycine max (L.) Merr.] is a unique crop species because it has high levels of both protein and oil in its seed. Of the many quantitative trait loci (QTL) controlling soybean seed protein content, alleles of the cqSeed protein-003 QTL on chromosome 20 exert the greatest additive effect. The high-protein allele exists in both cultivated and wild soybean (Glycine soja Siebold & Zucc.) germplasm. Our objective was to fine map this QTL to enable positional-based cloning of its underlying causative gene(s). Fine mapping was achieved by developing and testing a series of populations in which the chromosomal region surrounding the segregating high- versus low-protein alleles was gradually narrowed, using marker-based detection of recombinant events. The resultant 77.8 kb interval was directly sequenced from a G. soja source and compared with the reference genome to identify structural and sequence polymorphisms. An insertion/deletion variant detected in Glyma.20G85100 was found to have near-perfect +/- concordance with high/low-protein allele genotypes inferred for this QTL in parents of published mapping populations. The indel structure was concordant with an evolutionarily recent insertion of a TIR transposon into the gene in the low-protein lineage. Seed protein was significantly greater in soybean expressing an RNAi hairpin downregulation element in two independent events relative to control null segregant lineages. We conclude that a transposon insertion within the CCT domain protein encoded by the Glyma.20G85100 gene accounts for the high/low seed protein alleles of the cqSeed protein-003 QTL

The EVIDENT-trial: protocol and rationale of a multicenter randomized controlled trial testing the effectiveness of an online-based psychological intervention

Klein JP, Berger T, Schroeder J, et al. The EVIDENT-trial: protocol and rationale of a multicenter randomized controlled trial testing the effectiveness of an online-based psychological intervention. BMC Psychiatry. 2013;13(1): 239.Background: Depressive disorders are among the leading causes of worldwide disability with mild to moderate forms of depression being particularly common. Low-intensity treatments such as online psychological treatments may be an effective way to treat mild to moderate depressive symptoms and prevent the emergence or relapse of major depression. Methods/Design: This study is a currently recruiting multicentre parallel-groups pragmatic randomized-controlled single-blind trial. A total of 1000 participants with mild to moderate symptoms of depression from various settings including in-and outpatient services will be randomized to an online psychological treatment or care as usual (CAU). We hypothesize that the intervention will be superior to CAU in reducing depressive symptoms assessed with the Personal Health Questionnaire (PHQ-9, primary outcome measure) following the intervention (12 wks) and at follow-up (24 and 48 wks). Further outcome parameters include quality of life, use of health care resources and attitude towards online psychological treatments. Discussion: The study will yield meaningful answers to the question of whether online psychological treatment can contribute to the effective and efficient prevention and treatment of mild to moderate depression on a population level with a low barrier to entry

Equalizers for Transmultiplexers in Orthogonal Multiple Carrier Data Transmission

Orthogonal multiple carrier data transmission systems are eciently realized using modied DFT transmulti-plexer lter banks. In data transmission applications, a non-ideal transmission channel causes distortions such as intersymbol interference and crosstalk between the subrate bands of the transmultiplexer. Hence, in order to equalize these distortions, subband equalizers, which aect the intersymbol interference and crosstalk beha-vior, are considered for implementation. The special structure of modied DFT transmultiplexers requires a discussion concerning the various possibilities of placing the subband equalizers at the receiver. Wiener solutions and LMS adaptive algorithms for various new subband equalizer structures are derived and compared by means of simulation results.

Hair and stress: A pilot study of hair and cytokine balance alteration in healthy young women under major exam stress.

Mouse models show that experimental stress mimicking prolonged life-stress exposure enhances neurogenic inflammation, induces adaptive immunity cytokine-imbalance characterized by a shift to Type 1 T-helper cell cytokines and increases apoptosis of epithelial cells. This affects hair growth in otherwise healthy animals. In this study, we investigate whether a prolonged naturalistic life-stress exposure affects cytokine balance and hair parameters in healthy humans. 33 (18 exam, 15 comparison) female medical students with comparable sociobiological status were analyzed during a stressful final examination period, at three points in time (T) 12 weeks apart. T1 was before start of the learning period, T2 between the three-day written exam and an oral examination, and T3 after a 12 week rest and recovery from the stress of the examination period. Assessments included: self-reported distress and coping strategies (Perceived Stress Questionnaire [PSQ], Trier Inventory for the Assessment of Chronic Stress [TICS]), COPE), cytokines in supernatants of stimulated peripheral blood mononucleocytes (PBMCs), and trichogram (hair cycle and pigmentation analysis). Comparison between students participating in the final medical exam at T2 and non-exam students, revealed significantly higher stress perception in exam students. Time-wise comparison revealed that stress level, TH1/TH2 cytokine balance and hair parameters changed significantly from T1 to T2 in the exam group, but not the control. However, no group differences were found for cytokine balance or hair parameters at T2. The study concludes that in humans, naturalistic stress, as perceived during participation in a major medical exam, has the potential to shift the immune response to TH1 and transiently hamper hair growth, but these changes stay within a physiological range. Findings are instructive for patients suffering from hair loss in times of high stress. Replication in larger and more diverse sample populations is required, to assess suitability of trichogram analysis as biological outcome for stress studies