Untersuchungen zum toxikologischen Potential Uranabbau-assoziierter Verbindungen und kontaminierter Gewässerproben aus dem Ronneburger Wismut-Gebiet in humanen Kolonzellen

Ziel der vorliegenden Arbeit war es, ausgewählte Wasserproben aus dem ehemaligen Ronneburger Uranbergbaugebiet bzw. die Leitsubstanzen Eisen und Uran hinsichtlich ihrer lokalen bzw. systemischen Wirkungspotentiale in humanen Kolonzellen und Leukozyten zu charakterisieren. Desweiteren sollte geprüft werden, ob Apfelpolyphenole chemoprotektiv gegenüber Eisen und anderen Genotoxinen wirken. Eisen erhöhte in physiologischen Konzentrationen das Zellwachstum in Kolonkarzinomzellen, in hohen Konzentrationen wurde das Zellwachstum gestoppt und reaktive Sauerstoffspezies gebildet. Eisen wirkte genotoxisch in verschiedenen humanen Kolonzellen und humanen Leukozyten. Bereits in geringen Konzentrationen inhibierte Uran das Wachstum in humanen Kolonkarzinomzellen. Uran wirkt genotoxisch und klastogen in humanen Kolonzellen. Die kontaminierten Wasserproben haben das Potential zur Bildung von reaktiven Sauerstoffspezies und schädigen die DNA humaner Kolonzellen. Der Apfelextrakt verminderte die genotoxischen Wirkungen der Peroxide H2O2 und Cum-OOH. Bezüglich Fe-NTA-induzierter Schäden wirkte der polyphenolreiche Extrakt jedoch pro-oxidativ

FAS-Based Cell Depletion Facilitates the Selective Isolation of Mouse Induced Pluripotent Stem Cells

Cellular reprogramming of somatic cells into induced pluripotent stem cells (iPSC) opens up new avenues for basic research and regenerative medicine. However, the low efficiency of the procedure remains a major limitation. To identify iPSC, many studies to date relied on the activation of pluripotency-associated transcription factors. Such strategies are either retrospective or depend on genetically modified reporter cells. We aimed at identifying naturally occurring surface proteins in a systematic approach, focusing on antibody-targeted markers to enable live-cell identification and selective isolation. We tested 170 antibodies for differential expression between mouse embryonic fibroblasts (MEF) and mouse pluripotent stem cells (PSC). Differentially expressed markers were evaluated for their ability to identify and isolate iPSC in reprogramming cultures. Epithelial cell adhesion molecule (EPCAM) and stage-specific embryonic antigen 1 (SSEA1) were upregulated early during reprogramming and enabled enrichment of OCT4 expressing cells by magnetic cell sorting. Downregulation of somatic marker FAS was equally suitable to enrich OCT4 expressing cells, which has not been described so far. Furthermore, FAS downregulation correlated with viral transgene silencing. Finally, using the marker SSEA-1 we exemplified that magnetic separation enables the establishment of bona fide iPSC and propose strategies to enrich iPSC from a variety of human source tissues

An Assist for Cognitive Diagnostics in Soccer: Two Valid Tasks Measuring Inhibition and Cognitive Flexibility in a Soccer-Specific Setting With a Soccer-Specific Motor Response

In professional soccer, players, coaches, and researchers alike recognize the importance of cognitive skills. Research addressing the relevance of cognitive skills has been based on the cognitive component skills approach (i.e., general cognitive processes) or the expert performance approach (i.e., sport-specific cognitive processes). Our project aimed to combine the strengths of both approaches to develop and validate cognitive tasks measuring inhibition and cognitive flexibility in a soccer-specific setting with a soccer-specific motor response. In the main study 77 elite youth soccer players completed a computerized version of the standard flanker and number–letter tasks as well as flanker and number–letter tasks requiring a soccer-specific motor response (i.e., pass) in a soccer-specific setting (i.e., the SoccerBot360). Results show good reliability for both tasks. For the SoccerBot360 number–letter task, switch effects for response times and accuracy and acceptable convergent validity were shown. A flanker effect for response time but not accuracy was apparent. Due to no acceptable convergent validity, the flanker task was revised (i.e., adaptation of stimuli) and 63 adult soccer players participated in a follow-up validation study in the SoccerBot100. The revised flanker task showed the flanker effect for response time, but not for accuracy. However, acceptable convergent validity for response time was present. Thus, the soccer-specific number–letter and to some extent the soccer-specific flanker task show potential to be used as a valid cognitive diagnostic tool by soccer clubs.Peer Reviewe

Does Particulate Air Pollution Contribute to Infant Death? A Systematic Review

There is now substantial evidence that both short- and long-term increases in ambient air pollution are associated with increased mortality and morbidity in adults and children. Children’s health is particularly vulnerable to environmental pollution, and infant mortality is still a major contributor to childhood mortality. In this systematic review we summarize and evaluate the current level of epidemiologic evidence of an association between particulate air pollution and infant mortality. We identified relevant publications using database searches with a comprehensive list of search terms and other established search methods. We included articles in the review according to specified inclusion criteria. Fifteen studies met our inclusion criteria. Evidence of an association between particulate air pollution and infant mortality in general was inconsistent, being reported from locations with largely comparable pollution levels. There was some evidence that the strength of association with particulate matter differed by subgroups of infant mortality. It was more consistent for post-neonatal mortality due to respiratory causes and sudden infant death syndrome. Differential findings for various mortality subgroups within studies suggest a stronger association of particulate air pollution with some causes of infant death. Research is needed to confirm and clarify these links, using the most appropriate methodologies for exposure assessment and control of confounders

\b{eta}-delayed three-proton decay of 31Ar

The beta decay of 31Ar, produced by fragmentation of a 36Ar beam at 880 MeV/nucleon, was investigated. Identified ions of 31Ar were stopped in a gaseous time projection chamber with optical readout allowing to record decay events with emission of protons. In addition to \b{eta}-delayed emission of one and two protons we have clearly observed the beta-delayed three-proton branch. The branching ratio for this channel in 31Ar is found to be 0.07(2)%.Comment: 5 pages, 3 figures, submitted to Physical Rev.

Nuclear Physics Experiments with Ion Storage Rings

In the last two decades a number of nuclear structure and astrophysics experiments were performed at heavy-ion storage rings employing unique experimental conditions offered by such machines. Furthermore, building on the experience gained at the two facilities presently in operation, several new storage ring projects were launched worldwide. This contribution is intended to provide a brief review of the fast growing field of nuclear structure and astrophysics research at storage rings.Comment: XVIth International Conference on Electro-Magnetic Isotope Separators and Techniques Related to their Applications, December 2--7, 2012 at Matsue, Japa

Present and Future Experiments with Stored Exotic Nuclei at Relativistic Energies

Recent progress is presented from experiments on masses and lifetimes of bare and few-electron exotic nuclei at GSI.Comment: Proceedings of International Conference on "Frontiers in Nuclear Structure, Astrophysics and Reactions", Kos, Greece, September 12-17, 200