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Grossmann M.,Arbeitskreis Meteore E.V. | Schmidt E.,Heidelberg University of Applied Sciences | Haussmann A.,TU Dresden
Applied Optics | Year: 2011

The first likely photographic observation of the tertiary rainbow caused by sunlight in the open air is reported and analyzed. Whereas primary and secondary rainbows are rather common and easily seen phenomena in atmospheric optics, the tertiary rainbow appears in the sunward side of the sky and is thuslargely masked by forward scattered light. Up to now, only a few visual reports and no reliable photographs of the tertiary rainbow are known. Evidence of a third-order rainbow has been obtained by using image processing techniques on a digital photograph that contains no obvious indication of such a rainbow. To rule out any misinterpretation of artifacts, we carefully calibrated the image in order to compare the observed bow's angular position and dispersion with those predicted by theory. © 2011 Optical Society of America.

Bailer J.,University of Heidelberg | Witthoft M.,University of Mannheim | Wagner H.,University of Heidelberg | Mier D.,University of Heidelberg | And 2 more authors.
Journal of Psychosomatic Research | Year: 2014

Objective: Previous studies demonstrated that a history of childhood trauma is linked to mental disorders in adulthood, particularly to depression. Adverse childhood experiences are also considered to contribute to the risk of hypochondriasis, but the results of previous studies have not been conclusive with respect to the strength and specificity of this association. Therefore, we compared the association of adverse childhood experiences with both hypochondriasis and depression. Methods: Fifty-eight patients with hypochondriasis, 52 patients with depression, and 52 healthy control participants completed the Childhood Trauma Questionnaire (CTQ) which assesses 5 varieties of abuse and neglect. A clinical interview (SCID-I) was used to establish DSM-IV diagnoses. Associations between childhood maltreatment, hypochondriasis and depression were estimated by means of analyses of variance and multiple linear regression analyses. Results: In comparison to hypochondriacal and healthy participants, patients with a current depressive disorder reported more emotional abuse as well as more emotional and physical neglect during childhood. Patients with hypochondriasis reported more emotional neglect than healthy individuals. However, when predicting the CTQ trauma types by diagnostic category adjusting for sex and comorbid DSM-IV diagnoses, emotional abuse, emotional neglect, physical abuse, physical neglect, as well as the CTQ total score were significantly associated with depression, but none of the CTQ scores was significantly related to hypochondriasis. Conclusions: The findings suggest a robust association of childhood maltreatment with depression but not with hypochondriasis. This result does not support etiological models of hypochondriasis which rely on childhood maltreatment as a risk factor for the development of this disorder. © 2014 Elsevier Inc.

Ubl B.,University of Heidelberg | Kuehner C.,University of Heidelberg | Kirsch P.,University of Heidelberg | Ruttorf M.,University of Heidelberg | And 2 more authors.
Psychological Medicine | Year: 2015

Dysfunctional behavioural and neural processing of reward has been found in currently depressed individuals. However, little is known about altered reward processing in remitted depressed individuals. Method. A total of 23 medication-free individuals with remitted major depressive disorder (rMDD) and 23 matched healthy controls (HCs) performed a reward task during functional magnetic resonance imaging. We also investigated reward dependence, novelty seeking and harm avoidance using the Tridimensional Personality Questionnaire and their association with neural responses of reward processing. Results. Compared to HCs, individuals with rMDD exhibited enhanced responses to reward-predicting cues in the hippocampus, amygdala and superior frontal gyrus. When reward was delivered, rMDD subjects did not significantly differ from HCs. In both groups neural activity during reward anticipation was negatively correlated with harm avoidance. Conclusions. Our results show that rMDD is characterized by hyperactivation in fronto-limbic regions during reward anticipation. Alterations in neural activation during reward processing might reflect an increased effort in remitted depressed individuals to allocate neural activity for executive and evaluative processes during anticipatory reward processing. © 2015 Cambridge University Press.

Lechner A.,University of California at San Diego | Eustaquio A.S.,University of California at San Diego | Eustaquio A.S.,Pfizer | Gulder T.A.M.,University of California at San Diego | And 3 more authors.
Chemistry and Biology | Year: 2011

The chlorinated natural product salinosporamide A is a potent 20S proteasome inhibitor currently in clinical trials as an anticancer agent. To deepen our understanding of salinosporamide biosynthesis, we investigated the function of a LuxR-type pathway-specific regulatory gene, salR2, and observed a selective effect on the production of salinosporamide A over its less active aliphatic analogs. SalR2 specifically activates genes involved in the biosynthesis of the halogenated precursor chloroethylmalonyl-CoA, which is a dedicated precursor of salinosporamide A. Specifically, SalR2 activates transcription of two divergent operons - one of which contains the unique S-adenosyl-L-methionine-dependent chlorinase encoding gene salL. By applying this knowledge to rational engineering, we were able to selectively double salinosporamide A production. This study exemplifies the specialized regulation of a polyketide precursor pathway and its application to the selective overproduction of a specific natural product congener. © 2011 Elsevier Ltd. All Rights Reserved.

Forg T.,Mannheim University of Applied Sciences | Hafner M.,Mannheim University of Applied Sciences | Hafner M.,University of Heidelberg | Hafner M.,Heidelberg University of Applied Sciences | And 2 more authors.
PLoS ONE | Year: 2014

The homodimeric transmembrane receptor endoglin (CD105) plays an important role in angiogenesis. This is highlighted by mutations in its gene, causing the vascular disorder HHT1. The main role of endoglin function has been assigned to the modulation of transforming growth factor β and bone morphogenetic protein signalling in endothelial cells. Nevertheless, other functions of endoglin have been revealed to be involved in different cellular functions and in other cell types than endothelial cells. Compared to the exploration of its natural function, little experimental data have been gathered about the mode of action of endoglin HHT mutations at the cellular level, especially missense mutations, and to what degree these might interfere with normal endoglin function. In this paper, we have used fluorescence-based microscopic techniques, such as bimolecular fluorescence complementation (BiFC), immunofluorescence staining with the endoglin specific monoclonal antibody SN6, and protein interaction studies by Förster Resonance Energy Transfer (FRET) to investigate the formation and cellular localisation of possible homo- and heterodimers composed of endoglin wild-type and endoglin missense mutant proteins. The results show that all of the investigated missense mutants dimerise with themselves, as well as with wild-type endoglin, and localise, depending on the position of the affected amino acid, either in the rough endoplasmic reticulum (rER) or in the plasma membrane of the cells. We show that the rER retained mutants reduce the amount of endogenous wild-type endoglin on the plasma membrane through interception in the rER when transiently or stably expressed in HMEC-1 endothelial cells. As a result of this, endoglin modulated TGF-β1 signal transduction is also abrogated, which is not due to TGF-β receptor ER trafficking interference. Protein interaction analyses by FRET show that rER located endoglin missense mutants do not perturb protein processing of other membrane receptors, such as TβRII, ALK5 or ALK1. © 2014 Förg et al.

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