University of Basel

About: University of Basel is a education organization based out in Basel, Basel-Stadt, Switzerland. It is known for research contribution in the topics: Population & Gene. The organization has 25084 authors who have published 52975 publications receiving 2388002 citations. The organization is also known as: Universität Basel & Basel University.

Exposure to endotoxin or other bacterial components might protect against the development of atopy.

Abstract: Background Several recent studies have shown that growing up on a farm confers significant protection against the development of atopy. These findings point particularly towards the importance of exposure to stable dust and farm animals. It has furthermore been reported that endotoxin, an intrinsic part of the outer membrane of gram negative bacteria, is abundant in environments where livestock and poultry is kept. The aim of this study was therefore to measure the level of environmental endotoxin exposure in homes of farmers' children, children with regular contact to livestock and control children with no contact to farm animals. Methods Eighty-four farming and nonfarming families were identified in rural areas in Southern Germany and Switzerland. Samples of settled and airborne dust were collected in stables, and of settled dust indoors from kitchen floors and the children's mattresses. Endotoxin concentrations were determined by a kinetic Limulus assay. Results Endotoxin concentrations were highest in stables of farming families, but were also significantly higher indoors in dust from kitchen floors (143 EU/mg vs 39 EU/mg, P<0.001) and children's mattresses (49479 EU/m 2 vs 9383 EU/m 2 , P<0.001) as compared to control children from nonfarming families. In addition, endotoxin levels were also significantly higher in mattresses and dust from kitchen floors in households where children had regular contact to farm animals (38.6 EU/mg and 23340 EU/m 2 , respectively) as compared to control subjects. Conclusion We propose that the level of environmental exposure to endotoxin and other bacterial wall components is an important protective determinant for the development of atopic diseases in childhood.

Tissue microarrays for rapid linking of molecular changes to clinical endpoints.

Abstract: Advances in genomics and proteomics are dramatically increasing the need to evaluate large numbers of molecular targets for their diagnostic, predictive or prognostic value in clinical oncology. Conventional molecular pathology techniques are often tedious, time-consuming, and require a lot of tissue, thereby limiting both the number of tissues and the number of targets that can be evaluated. Here, we demonstrate the power of our recently described tissue microarray (TMA) technology in analyzing prognostic markers in a series of 553 breast carcinomas. Four independent TMAs were constructed by acquiring 0.6 mm biopsies from one central and from three peripheral regions of each of the formalin-fixed paraffin embedded tumors. Immunostaining of TMA sections and conventional "large" sections were performed for two well- established prognostic markers, estrogen receptor (ER) and progesterone receptor (PR), as well as for p53, another frequently examined protein for which the data on prognostic utility in breast cancer are less unequivocal. Compared with conventional large section analysis, a single sample from each tumor identified about 95% of the information for ER, 75 to 81% for PR, and 70 to 74% for p53. However, all 12 TMA analyses (three antibodies on four different arrays) yielded as significant or more significant associations with tumor-specific survival than large section analyses (p < 0.0015 for each of the 12 comparisons). A single sample from each tumor was sufficient to identify associations between molecular alterations and clinical outcome. It is concluded that, contrary to expectations, tissue heterogeneity did not negatively influence the predictive power of the TMA results. TMA technology will be of substantial value in rapidly translating genomic and proteomics information to clinical applications.

Host–parasite ‘Red Queen’ dynamics archived in pond sediment

Abstract: Antagonistic interactions between hosts and parasites are a key structuring force in natural populations, driving coevolution(1,2). However, direct empirical evidence of long-term host-parasite coevolution, in particular `Red Queen' dynamics-in which antagonistic biotic interactions such as host-parasite interactions can lead to reciprocal evolutionary dynamics-is rare(3-5), and current data, although consistent with theories of antagonistic coevolution, do not reveal the temporal dynamics of the process(6). Dormant stages of both the water flea Daphnia and its microparasites are conserved in lake sediments, providing an archive of past gene pools. Here we use this fact to reconstruct rapid coevolutionary dynamics in a natural setting and show that the parasite rapidly adapts to its host over a period of only a few years. A coevolutionary model based on negative frequency-dependent selection, and designed to mimic essential aspects of our host parasite system, corroborated these experimental results. In line with the idea of continuing host-parasite coevolution, temporal variation in parasite infectivity changed little over time. In contrast, from the moment the parasite was first found in the sediments, we observed a steady increase in virulence over time, associated with higher fitness of the parasite.

Database of Geneva stellar evolution tracks and isochrones for (UBV) J (RI) C JHKLL'M, HST-WFPC2, Geneva and Washington photometric systems

Abstract: We have used an updated version of the empirically and semi-empirically calibrated B aS eL library of synthetic stellar spectra of Lejeune et al.([CITE], [CITE]) and Westera et al.([CITE]) to calculate synthetic photometry in the (UBV) J (RI) C JHKLL ′ M , HST-WFPC2, Geneva, and Washington systems for the entire set of non-rotating Geneva stellar evolution models covering masses from 0.4-0.8 to 120-150 and metallicities (1/50 ) to 0.1 (5 ). The results are provided in a database which includes all individual stellar tracks and the corresponding isochrones covering ages from 103 yr to 16-20 Gyr in time steps of 0.05 dex. The database also includes a new grid of stellar tracks of very metal-poor stars () from calculated with the Geneva stellar evolution code.