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The sharpest images on Paranal are produced by the beam-combining instruments of the Very Large Telescope Interferometer (VLTI). Currently, the VLTI is close to completing a transitional period, moving away from the first generation of instruments (AMBER, MIDI) and offering new instruments and subsystems to the community. In this article, we report on the life and achievements of the recently decommissioned, near-infrared beam combiner instrument AMBER, the most prolific optical interferometric instrument to date., Published in The Messenger vol. 174, pp. 8-13, December 2018.

The number of magnetic stars detected among massive stars is small; nevertheless, the role played by the magnetic field in stellar evolution cannot be disregarded. Links between line profile variability, enhancements/depletions of surface chemical abundances, and magnetic fields have been identified for low-mass B-stars, but for the O-type domain this is almost unexplored. Based on FORS 2 and HARPS spectropolarimetric data, we present the first detection of a magnetic field in HD 54879, a single slowly rotating O9.7 V star. Using two independent and different techniques we obtained the firm detection of a surface average longitudinal magnetic field with a maximum amplitude of about 600 G, in modulus. A quantitative spectroscopic analysis of the star with the stellar atmosphere code fastwind results in an effective temperature and a surface gravity of 33 000 ± 1000 K and 4.0 ± 0.1 dex. The abundances of carbon, nitrogen, oxygen, silicon, and magnesium are found to be slightly lower than solar, but compatible within the errors. We investigate line-profile variability in HD 54879 by complementing our spectra with spectroscopic data from other recent OB-star surveys. The photospheric lines remain constant in shape between 2009 and 2014, although Hα shows a variable emission. The Hα emission is too strong for a standard O9.7 V and is probably linked to the magnetic field and the presence of circumstellar material. Its normal chemical composition and the absence of photospheric line profile variations make HD 54879 the most strongly magnetic, non-variable single O-star detected to date. Based on observations made with ESO telescopes at the La Silla and Paranal observatories under programme ID 191.D-0255(C, F).Appendix A is available in electronic form at http://www.aanda.org 16 pages, accepted for publication in A&A ispartof: Astronomy & Astrophysics vol:581 status: published

The nucleotide sequence encoding the SR protein of Streptococcus mutans OMZ 175 (serotype f) has been determined. The sr gene consists of 4667 bp and codes for a 171177 Da protein. Comparison of the inferred amino acid sequence with the one of PAc antigen from S. mutans MT 8148 (serotype c) indicates a 88% conservation of amino acid residues which reflects the close relatedness of both proteins. Major differences in amino acid composition are located at the C-terminal part of the sequence where only 298 amino acids of the terminal 420 are conserved.The nucleotide sequence encoding the SR protein of Streptococcus mutans OMZ 175 (serotype f) has been determined. The sr gene consists of 4667 bp and codes for a 171177 Da protein. Comparison of the inferred amino acid sequence with the one of PAc antigen from S. mutans MT 8148 (serotype c) indicates a 88% conservation of amino acid residues which reflects the close relatedness of both proteins. Major differences in amino acid composition are located at the C-terminal part of the sequence where only 298 amino acids of the terminal 420 are conserved.

Niemann-Pick type C disease (NPC) is an inherited disorder mainly caused by loss-of- function mutations in the NPC1 gene, that lead to intracellular cholesterol accomulation and disturbed cholesterol homeostasis. Similarly to Alzheimer's disease (AD), NPC is associated with progressive neurodegeneration and altered metabolism of amyloid precursor protein (APP). Liver X receptors (LXRs), the key transcriptional regulators of cholesterol homeostasis, were reported to play neuroprotective roles in NPC mice. We investigated the impacts of LXRs on APP metabolism in mutant CHO cells lacking NPC1 gene (-NPC1 cells). Pharmacological activation of LXRs in -NPC1 cells tended to reduce the sAPP/flAPP ratio and sAPPβ levels as well as to increase the CTFs/flAPP ratio, resulting in the decreased levels of amyloid β (Aβ) peptides. - NPC1 cells treated with LXR agonist TO901317 (TO90) displayed a modest up-regulation of cholesterol efflux to apolipoprotein A-I (apoA- I) but not to HDL3 or in the absence of extracellular cholesterol acceptors. The observed similar reduction of Aβ levels upon TO90 treatment in the presence or in the absence of extracellular apoA-I indicated cholesterol-efflux independent effect of TO90 on Aβ levels. Furthermore, TO90 had no effect on the cholesterol synthesis rate in -NPC1 cells, while it reduced the rate of cholesterol esterification. The obtained results indicate that LXR activation may decrease Aβ levels in NPC1-deficient conditions. The underlying mechanism of this action does not appear to be related to effects on cholesterol efflux or synthesis rates.

Besides mites, filamentous fungi and yeasts play an important role as domestic allergens. Among different allergen avoidance strategies the efficacy of synthetic mattress encasings has been demonstrated for the reduction of house dust mites. Whether these synthetic encasings arc also able to reduce the growth of fungi on the mattress under domestic conditions has not been assessed so far. To determine if the fungal growth on mattresses can be reduced by the use of synthetic encasings we assessed the fungal colonisation of mattresses covered either by conventional cotton encasings or by polyurethane encasings impermeable to particles > 3 mum. Within a 12-month period dust samples were obtained from the mattresses. Fungal quantities were measured by counting colonies on agar plates incubated at 20 degreesC and 37 degreesC. The counts of fungi were significantly higher on mattresses with cotton encasings. Penicillium spp. and Aspergillus spp. were isolated most frequently. Therefore the application of synthetic encasings with similar properties to the encasings used in this investigation is recommended as part of an allergen avoidance strategy for patients sensitised to fungal allergens.