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The decomposition behavior of Ni-rich Ni-Ti was reassessed using Tomographic Atom Probe (TAP) and Laser Assisted Wide Angle Tomographic Atom Probe. Single crystalline specimens of Ni-11.3 at.% Ti were investigated, the states selected from the decomposition path were the metastable y" and y' states introduced on the basis of small-angle neutron scattering (SANS) and the two-phase model for evaluation. The composition values of the precipitates in these states could not be confirmed by APT data as the interface of the ordered precipitates may not be neglected. The present results rather suggest to apply a three-phase model for the interpretation of SANS measurements, in which the width of the interface remains nearly unchanged and the L12 structure close to 3:1 stoichiometry is maintained in the core of the precipitates from the y" to the y' state. [ABSTRACT FROM AUTHOR]

tRNA superwobbling, used by certain bacteria and organelles, is an intriguing decoding concept in which a single tRNA isoacceptor is used to decode all synonymous codons of a four-fold degenerate codon box. While Escherichia coli relies on three tRNAGly isoacceptors to decode the four glycine codons (GGN), Mycoplasma mycoides requires only a single tRNAGly. Both organisms express tRNAGly with the anticodon UCC, which are remarkably similar in sequence but different in their decoding ability. By systematically introducing mutations and altering the number and type of tRNA modifications using chemically synthesized tRNAs, we elucidated the contribution of individual nucleotides and chemical groups to decoding by the E. coli and M. mycoides tRNAGly. The tRNA sequence was identified as the key factor for superwobbling, revealing the T-arm sequence as a novel pivotal element. In addition, the presence of tRNA modifications, although not essential for providing superwobbling, was shown to delicately fine-tune and balance the decoding of synonymous codons. This emphasizes that the tRNA sequence and its modifications together form an intricate system of high complexity that is indispensable for accurate and efficient decoding., (© The Author(s) 2023. Published by Oxford University Press on behalf of Nucleic Acids Research.)

During initiation, the ribosome is tasked to efficiently recognize open reading frames (ORFs) for accurate and fast translation of mRNAs. A critical step is start codon recognition, which is modulated by initiation factors, mRNA structure, a Shine Dalgarno (SD) sequence and the start codon itself. Within the Escherichia coli genome, we identified more than 50 annotated initiation sites harboring AUGUG or GUGUG sequence motifs that provide two canonical start codons, AUG and GUG, in immediate proximity. As these sites may challenge start codon recognition, we studied if and how the ribosome is accurately guided to the designated ORF, with a special focus on the SD sequence as well as adenine at the fourth coding sequence position (A4). By in vitro and in vivo experiments, we characterized key requirements for unambiguous start codon recognition, but also discovered initiation sites that lead to the translation of both overlapping reading frames. Our findings corroborate the existence of an ambiguous translation initiation mechanism, implicating a multitude of so far unrecognized ORFs and translation products in bacteria., (© The Author(s) 2022. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Objective: In view of ethical considerations and the limited resources in intensive care medicine, the present investigation aims to give a descriptive overview of the prognosis and therapeutic activity for the oldest age group of elderly patients admitted to an intensive care unit (ICU) in comparison with younger ICU patients., Patients and Methods: 3069 patients admitted to the ICU during a seven-year period were categorized into four age groups: under 65 years (48%), 65 to 74 years (26%), 75 to 85 years (22%) and 85 years or older (5%). Type and reason for ICU admission, length of ICU stay, severity of illness as measured by the simplified acute physiology score (SAPS)-II, level of provided care as measured by the simplified therapeutic intervention scoring system (TISS)-28, and vital status at the date of ICU discharge were recorded., Results: The ICU mortality rate of patients aged 85 years or older was significantly higher than in patients under 65 (OR of mortality: 1.8, p < 0.001). Non-survivors had higher SAPS II levels (even when excluding age points) in all age groups, but higher daily average TISS points only in patients under 85. The daily average TISS score was negatively correlated to age (r = -0.03; p < 0.001) and was significantly lower in the oldest group when compared with all the younger groups (p < 0.001). The oldest patients had a significantly shorter length of stay (median: 2; interquartile range [IQR] 1-3, p < 0.001) than the younger patient groups., Conclusions: Within the very elderly population, age is an important and independent predictor of mortality, but acute severity of illness is even more strongly associated with mortality. Consequently, age alone may be an inappropriate criterion for allocation of ICU resources.

Demand for rabies hyperimmunoglobulin has increased recently, requiring optimization of vaccination schemes for immunized plasma donors. Possible resemblance of rabies vaccine to blood group antigens and consequential association of the immune response to rabies vaccine and blood group or corresponding isoantibodies has not yet been investigated. We analyzed antirabies antibodies after rabies vaccination and ABO blood group in 142 individuals, and isoantibody titers in 92 of those individuals. We did not find any correlation of the immune response with blood group or isoantibody levels. There was also no correlation with the sex of individuals, but there was a weak correlation between age and rabies-specific antibody level. Rabies vaccination schemes for immunized donors cannot be optimized on the basis of blood groups or isoantibody titers.