Abstract
Poly(ADP-ribosyl)ation regulates numerous cellular processes like genome maintenance and cell death, thus providing protective functions but also contributing to several pathological ...conditions. Poly(ADP-ribose) (PAR) molecules exhibit a remarkable heterogeneity in chain lengths and branching frequencies, but the biological significance of this is basically unknown. To unravel structure-specific functions of PAR, we used PARP1 mutants producing PAR of different qualities, i.e. short and hypobranched (PARP1\G972R), short and moderately hyperbranched (PARP1\Y986S), or strongly hyperbranched PAR (PARP1\Y986H). By reconstituting HeLa PARP1 knockout cells, we demonstrate that PARP1\G972R negatively affects cellular endpoints, such as viability, cell cycle progression and genotoxic stress resistance. In contrast, PARP1\Y986S elicits only mild effects, suggesting that PAR branching compensates for short polymer length. Interestingly, PARP1\Y986H exhibits moderate beneficial effects on cell physiology. Furthermore, different PARP1 mutants have distinct effects on molecular processes, such as gene expression and protein localization dynamics of PARP1 itself, and of its downstream factor XRCC1. Finally, the biological relevance of PAR branching is emphasized by the fact that branching frequencies vary considerably during different phases of the DNA damage-induced PARylation reaction and between different mouse tissues. Taken together, this study reveals that PAR branching and chain length essentially affect cellular functions, which further supports the notion of a ‘PAR code’.
Prostate cancer (PCa) in dogs is a highly malignant disease akin to its human counterpart. In contrast to the situation in humans, multi-gene approaches facilitating risk stratification of canine PCa ...are barely established. The aims of this study were the characterization of the transcriptional landscape of canine PCa and the identification of diagnostic, prognostic and/or therapeutic biomarkers through a multi-step screening approach. RNA-Sequencing of ten malignant tissues and fine-needle aspirations (FNA), and 14 nonmalignant tissues and FNAs was performed to find differentially expressed genes (DEGs) and deregulated pathways. The 4098 observed DEGs were involved in 49 pathways. These 49 pathways could be grouped into five superpathways summarizing the hallmarks of canine PCa: (i) inflammatory response and cytokines; (ii) regulation of the immune system and cell death; (iii) cell surface and PI3K signaling; (iv) cell cycle; and (v) phagosome and autophagy. Among the highly deregulated, moderately to strongly expressed DEGs that were members of one or more superpathways, 169 DEGs were listed in relevant databases and/or the literature and included members of the PCa pathway, oncogenes, prostate-specific genes, and druggable genes. These genes are novel and promising candidate diagnostic, prognostic and/or therapeutic canine PCa biomarkers.
The aim of the present study was to determine if colostrum and the equipment for harvesting and feeding colostrum are sources of fecal ESBL/AmpC-producing Escherichia coli (ESBL/AmpC-E. coli) in ...calves. Therefore, 15 male calves fed with pooled colostrum on a dairy farm and held individually in an experimental barn, the colostrum pool and the equipment for harvesting and feeding colostrum were sampled and analyzed for the occurrence of ESBL/AmpC-E. coli. The ESBL-AmpC-E. coli suspicious isolates were subjected to whole-genome sequence analysis. Forty-three of 45 fecal samples were tested positive for ESBL/AmpC-E. coli. In the colostrum sample and in the milking pot, we also found ESBL/AmpC-E. coli. All 45 E. coli isolates were ESBL-producers, mainly commensal sequence type (ST) 10, but also human-extraintestinal pathogenic E. coli ST131 and ST117 were found. The clonal identity of six fecal isolates with the ESBL-E. coli isolate from the colostrum and of five fecal isolates with the strain from the milking pot demonstrates that the hygiene of colostrum or the colostrum equipment can play a significant role in the spread of ESBL-E. coli. Effective sanitation procedures for colostrum harvesting and feeding equipment are crucial to reduce the ESBL-E. coli shedding of neonatal dairy calves.
The aim of the study was to determine the prevalence of ESBL/AmpC-producing Escherichia (E.) coli and to investigate their on-farm distribution on an exemplary dairy farm. For this purpose, sample ...sizes were calculated, and fecal samples were collected from cattle of all ages and analyzed for the presence of ESBL/AmpC-E. coli using selective media supplemented with cefotaxime. These antibiotic-resistant bacteria were detected in 22.5% of the samples tested. The prevalence was highest in the calf age group, in which 100% of the collected fecal samples were positive. With increasing age, the prevalence decreased in the other sample groups. While ESBL/AmpC E. coli could still be detected in young stock (15%) and breeding heifers (5%), no resistant pathogens could be detected in adult animals. Whole-genome sequencing of the ESBL/AmpC-E. coli isolates revealed, first, that all isolates were ESBL producers (CTX-M-1 and CTX-M-15) and, second, that ST362, which is known as a biofilm producer, was dominant in the calves (85%, n = 17). Based on these results and the evaluation of a questionnaire, possible causes for the occurrence of ESBL/AmpC-E. coli were discussed and recommendations for the reduction in transmission were formulated. Unlike most German dairy farms, no waste milk feeding was apparent; therefore, factors reducing ESBL/AmpC-E. coli are primarily related to an improvement in hygiene management to prevent biofilms, e.g., in nipple buckets, but also to question the use of antibiotics, e.g., in the treatment of diarrheic calves.
We present time-resolved scanning x-ray microscopy measurements with picosecond photo-excitation via a tailored infrared pump laser at a scanning transmission x-ray microscope. Specifically, we image ...the laser-induced demagnetization and remagnetization of thin ferrimagnetic GdFe films proceeding on a few nanoseconds timescale. Controlling the heat load on the sample via additional reflector and heatsink layers allows us to conduct destruction-free measurements at a repetition rate of 50 MHz. Near-field enhancement of the photo-excitation and controlled annealing effects lead to laterally heterogeneous magnetization dynamics which we trace with 30 nm spatial resolution. Our work opens new opportunities to study photo-induced dynamics on the nanometer scale, with access to picosecond to nanosecond time scales, which is of technological relevance, especially in the field of magnetism.
Enhanced recovery after surgery (ERAS) recommendations for cesarean section (ERAC), likely the most common reason for laparotomy in women, were issued in 2018–19. We examined how current ...perioperative management at cesarean section in Austrian hospitals aligns with ERAS recommendations.
We surveyed the 21 largest public obstetric units in Austria for alignment with 20 of the 31 strong ERAS recommendations regarding perioperative maternal care at cesarean section. We also looked at how the German-language clinical guideline for cesarean section (AWMF Guideline Sectio caesarea) aligns with ERAS recommendations.
The 21 obstetric units cared for about 51% of all births in Austria in 2019. Cesarean section rates ranged from 17.7% to 50.4%. All 21 units implemented the five strong recommendations regarding patient information and counselling, regional anesthesia, euvolemia and multimodal analgesia. The least implemented strong recommendation was the one for the use of pneumatic compression stockings to prevent thromboembolic disease (0/21 units). Overall, all 21 units implemented ≥11 and 13 (62%) implemented ≥15 (≥75%) of the 20 strong recommendations; no unit implemented all 20 strong recommendations. There were no differences in the implementation of strong recommendations according to hospital volume.
Even in the absence of formal adoption of ERAS program for cesarean section many perioperative ERAS recommendations are already implemented in Austria. The least implemented recommendations were the use of pneumatic compression stockings (0 of 21 units) and immediate catheter removal (4 of 21 units). Only 10 of the 20 ERAS recommendations we looked at are included in the current German-language clinical guideline for cesarean section.
Antimicrobial resistance (AMR) is a serious global health threat with extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales as the most critical ones. Studies on AMR in wild birds imply ...a possible dissemination function and indicate their potential role as sentinel animals. This study aimed to gain a deeper insight into the AMR burden of wild waterfowl by sampling semi-wild mallard ducks used as sentinels and to identify if AMR bacteria could be recommended to be added to the pathogens of public health risks to be screened for. In total, 376 cloacal and pooled fecal samples were collected from the sentinel plant over a period of two years. Samples were screened for ESBL-carrying E. coli and isolates found further analyzed using antimicrobial susceptibility testing and whole-genome sequencing. Over the sampling period, 4.26% (16/376) of the samples were positive for ESBL-producing E. coli. BlaCTX-M-1 and blaCTX-M-32 were the most abundant CTX-M types. Although none of the top global sequence types (ST) could be detected, poultry-derived ST115 and non-poultry-related STs were found and could be followed over time. The current study revealed low cases of ESBL-producing E. coli in semi-wild mallard ducks, which proves the suitability of sentinel surveillance for AMR detection in water-associated wildlife.
Single molecule localization microscopy (SMLM) is one of the key techniques that break the classical resolution limit in optical imaging. It is based on taking multiple recordings of a sample, each ...showing only a sparse arrangement of spatially well separated fluorescent molecules which can be localized at nanometer precision. While localizing along the lateral directions is usually straightforward, estimating axial positions at a comparable precision is known to be much harder, which is due to the relatively large depth of focus provided by the microscope optics. Whenever a molecule is sufficiently close to the coverslip, it becomes feasible to draw additional information from near field coupling effects: super-critical angle fluorescence (SAF) appears and can be exploited to boost the axial localization precision. Here we propose defocused imaging as a SMLM strategy that is capable of leveraging the information contained in SAF. We show that, regarding axial localization precision, our approach is superior to established SAF-based approaches. At the same time it is simple and can be conducted on any research-grade microscope where controlled defocusing on the order of a few hundred nanometers is possible.
Health authorities worldwide address older adults as a risk group for more serious illness and health complications associated with COVID-19, while social gerontologists have warned that addressing ...older adults as a risk group of COVID-19 bears the risk of reinforcing ageism. This paper empirically explores to what extent older adults perceive themselves as part of a COVID-19 risk group and how these perceptions influence their everyday lives and experiences of age and ageing. This paper draws upon data from a mixed-methods study on older adults' risk perceptions during COVID-19 in Lower Austria, including a representative survey on 521 adults (60+ years) and data from 20 semi-structured interviews. Approximately two-thirds of the respondents consider themselves at risk of COVID-19 and name age, in addition to pre-existing illness, as a contributing factor in this risk perception. Older adults with health constraints, and especially older men, have a higher probability of perceiving risk due to COVID-19. Additionally, older adults report that they experience being ‘suddenly seen as old’ or ‘being put into a box’ during the pandemic, which influenced their experiences and images of ageing. Our study provides insights into how perceived COVID-19 risk affects the everyday lives of older adults. Age-based categorisations of risk contribute to a shift in images of age and ageing, drawing on insecurity and risk, rather than successful and active ageing, to conceptualise later life.
MS/MS and associated database search algorithms are essential proteomic tools for identifying peptides. Due to their widespread use, it is now time to perform a systematic analysis of the various ...algorithms currently in use. Using blood specimens used in the HUPO Plasma Proteome Project, we have evaluated five search algorithms with respect to their sensitivity and specificity, and have also accurately benchmarked them based on specified false‐positive (FP) rates. Spectrum Mill and SEQUEST performed well in terms of sensitivity, but were inferior to MASCOT, X!Tandem, and Sonar in terms of specificity. Overall, MASCOT, a probabilistic search algorithm, correctly identified most peptides based on a specified FP rate. The rescoring algorithm, PeptideProphet, enhanced the overall performance of the SEQUEST algorithm, as well as provided predictable FP error rates. Ideally, score thresholds should be calculated for each peptide spectrum or minimally, derived from a reversed‐sequence search as demonstrated in this study based on a validated data set. The availability of open‐source search algorithms, such as X!Tandem, makes it feasible to further improve the validation process (manual or automatic) on the basis of “consensus scoring”, i.e., the use of multiple (at least two) search algorithms to reduce the number of FPs.∁
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