Vorbemerkung und Einleitung zu "Beredte Körper : bewegte Seelen ; zum Diskurs der doppelten Bewegung in Tanztexten
Bildhafte und andere Gedankensprünge : zweimal „Die schmutzigen Hände“ auf der Bühne
Sestrin-2, a repressor of PDGFRβ signalling, promotes cigarette smoke-
induced pulmonary emphysema in mice and is upregulated in patients
K. C. Kent Lloyd
Harald von Melchner
- Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. COPD is caused by chronic exposure to cigarette smoke and/or other environmental pollutants that are believed to induce reactive oxygen species (ROS) that gradually disrupt signalling pathways responsible for maintaining lung integrity. Here we identify the antioxidant protein Sestrin 2 (Sesn2) as a repressor of PDGFRβ signalling and PDGFRβ signalling as an upstream regulator of alveolar maintenance programs. In mice, the mutational inactivation of Sesn2 prevents the development of cigarette-smoke induced pulmonary emphysema by upregulating PDGFRβ expression via a selective accumulation of intracellular superoxide anions (O2-). We also show that SESN2 is overexpressed and PDGFRβ downregulated in the emphysematous lungs of patients with COPD and to a lesser extent in human lungs of habitual smokers without COPD, implicating a negative SESN2/PDGFRβ interrelationship in the pathogenesis of COPD. Taken together, our results imply that SESN2 could serve as both a biomarker and as a drug target in the clinical management of COPD.
Does social interaction destablise financial markets?
- With this paper, I propose a simple asset pricing model that accounts for the influence from social interaction. Investors are assumed to make up their mind about an asset’s price based on a forecasting strategy and its past profitability as well as on the contemporaneous expectations of other market participants. Empirically analysing stocks of the DAX30 index, I provide evidence that social interaction rather destabilises financial markets. Based on my results, I state that at least, it does not have a stabilising effect.
Analyst behaviour: the geography of social interaction
- An analyst who works in Germany is more likely to publish a high (low) price target regarding a DAX30 stock if other Germany based analysts are also optimistic (pessimistic) about the same stock. This finding is not biased by the fact that DAX30 companies are headquartered in Germany. In times of bull markets, price targets of analysts who regularly exchange their opinion are higher correlated compared to other analysts. This effect vanishes in a bearish market environment. This suggests that communication among analysts indeed plays an important role. However, analysts’ incentives induce them not to deviate too much from the overall average during an economic downturn.
Fluctuations of social influence: evidence from the behaviour of mutual fund managers during the economic crisis 2008/09
- In this paper, I analyse the reciprocal social influence on investment decisions within an international group of roughly 2000 mutual fund managers that invested in companies of the DAX30. Using a robust estimation procedure, I provide empirical evidence that in the average a fund manager puts 0.69% more portfolio weight on a particular stock, if other fund managers increase the corresponding position by 1%. The dynamics of this influence on portfolio weights suggest that fund managers adjust their behaviour according to the prevailing market situation and are more strongly influenced by others in times of an economic downturn. Analysing the working locations of the fund managers, I conclude that more than 90% of the magnitude of influence is due to pure observation. While this form of influence varies much in time, the magnitude of influence resulting from the exchange of opinion is more or less constant.
[Rezension zu:] Gisela Brünner. 2011. Gesundheit durchs Fernsehen. Linguistische Untersuchungen zur Vermittlung medizinischen Wissens und Aufklärung in Gesundheitssendungen. Duisburg: Universitätsverlag Rhein-Ruhr. 528 S.
Nina Jeanette Hofferberth
David Sebastian Sauer