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Background: Inflammatory processes are a cause of accelerated loss of muscle mass. Metabolic syndrome (MetS) is a highly prevalent age-related condition, which may promote and be promoted by inflammation. However, whether inflammation in MetS (metaflammation) is associated with lower muscle mass is still unclear. Methods: Complete cross-sectional data on body composition, MetS, and the inflammatory markers interleukin (IL)-1 beta, IL-6, IL-10, tumor necrosis factor (TNF), and C-reactive protein (CRP) were available for 1,377 BASE-II participants (51.1% women; 68 +/- 4 years old). Appendicular lean mass (ALM) was assessed by dual-energy X-ray absorptiometry. Low muscle mass (low ALM-to-BMI ratio [ALMBMI]) was defined according to the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project. Regression models, adjusted for an increasing number of confounders (sex, age, physical activity, morbidities, diabetes mellitus type II, TSH, albumin, HbA1c, smoking habits, alcohol intake, education, and energy intake/day), were used to calculate the association between low ALMBMI and high inflammation (tertile 3) according to MetS. Results: MetS was present in 36.2% of the study population, and 9% had low ALMBMI. In the whole study population, high CRP (odds ratio [OR]: 2.7 [95% CI: 1.6-4.7; p = 0.001]) and high IL-6 (OR: 2.1 [95% CI: 1.2-1.9; p = 0.005]) were associated with low ALMBMI. In contrast, no significant association was found between TNF, IL-10, or IL-1 beta with low ALMBMI. When participants were stratified by MetS, results for IL-6 remained significant only in participants with MetS. Conclusions: Among BASE-II participants, low ALMBMI was associated with inflammation. Low-grade inflammation triggered by disease state, especially in the context of MetS, might favor loss of muscle mass, so a better control of MetS might help to prevent sarcopenia. Intervention studies to test whether strategies to prevent MetS might also prevent loss of muscle mass seem to be promising.
Signaling trough p53is a major cellular stress response mechanism and increases upon nutrient stresses such as starvation. Here, we show in a human hepatoma cell line that starvation leads to robust nuclear p53 stabilization. Using BioID, we determine the cytoplasmic p53 interaction network within the immediate-early starvation response and show that p53 is dissociated from several metabolic enzymes and the kinase PAK2 for which direct binding with the p53 DNA-binding domain was confirmed with NMR studies. Furthermore, proteomics after p53 immunoprecipitation (RIME) uncovered the nuclear interactome under prolonged starvation, where we confirmed the novel p53 interactors SORBS1 (insulin receptor signaling) and UGP2 (glycogen synthesis). Finally, transcriptomics after p53 re-expression revealed a distinct starvation-specific transcriptome response and suggested previously unknown nutrient-dependent p53 target genes. Together, our complementary approaches delineate several nodes of the p53 signaling cascade upon starvation, shedding new light on the mechanisms of p53 as nutrient stress sensor. Given the central role of p53 in cancer biology and the beneficial effects of fasting in cancer treatment, the identified interaction partners and networks could pinpoint novel pharmacologic targets to fine-tune p53 activity.
Energetic charged particles trapped in planetary radiation belts are hazardous to spacecraft. Planned missions to iron-rich asteroids with possible strong remanent magnetic fields require an assessment of trapped particles energies. Using laboratory measurements of iron meteorites, we estimate the largest possible asteroid magnetic moment. Although weak compared to moments of planetary dynamos, the small body size may yield strong surface fields. We use hybrid simulations to confirm the formation of a magnetosphere with an extended quasi-dipolar region. However, the short length scale of the field implies that energetic particle motion would be nonadiabatic, making existing radiation belt theories not applicable. Our idealized particle simulations demonstrate that chaotic motions lead to particle loss at lower energies than those predicted by adiabatic theory, which may explain the energies of transiently trapped particles observed at Mercury, Ganymede, and Earth. However, even the most magnetized asteroids are unlikely to stably trap hazardous particles.
Push-ups represent one of the simplest and most popular strengthening exercise. The aim of this study was to systematically review and critically appraise the literature on the kinetics-related characteristics of different types of push-ups, with the objective of optimising training prescription and exercise-related load. A systematic search was conducted in the electronic databases PubMed, Google Scholar and Science Direct up to April 2018. Studies that reported kinetic data (e.g. initial and peak-force supported by the upper-limbs, impact-force, peak-flexion-moment of the elbow-joint, rate of propulsive- and impact-, and vertebral-joint compressive-forces) related to push-ups and included trained, recreational and untrained participants, were considered. The risk of bias in the included studies was assessed using the Critical Appraisal Skills Programme scale. From 5290 articles retrieved in the initial search, only 26 studies were included in this review. Kinetic data for 46 push-up variants were assessed. A limitation of the current review is that the relationship between our findings and actual clinical or practical consequences is not statistically proven but can only be inferred from our critical descriptive approach. Overall, this review provides detailed data on specific characteristics and intensities of push-up variations, in order to optimise exercise prescription for training and rehabilitation purposes.
IntroductionPostoperative delirium (POD) is a common and serious adverse event of surgery in older people. Because of its great impact on patients' safety and quality of life, identification of modifiable risk factors could be useful. Although preoperative medication intake is assumed to be an important modifiable risk factor, the impact of anticholinergic drugs on the occurrence of POD seems underestimated in elective surgery. The aim of this study was to investigate the association between preoperative anticholinergic burden and POD. We hypothesized that a high preoperative anticholinergic burden is an independent, potentially modifiable predisposing and precipitating factor of POD in older people. MethodsBetween November 2017 and April 2019, 1,470 patients of 70 years and older undergoing elective orthopedic, general, cardiac, or vascular surgery were recruited in the randomized, prospective, multicenter PAWEL trial. Anticholinergic burden of a sub-cohort of 899 patients, who did not receive a multimodal intervention for preventing POD, was assessed by two different tools at hospital admission: The established Anticholinergic Risk Scale (ARS) and the recently developed Anticholinergic Burden Score (ABS). POD was detected by confusion assessment method (CAM) and a validated post discharge medical record review. Logistic regression analyses were performed to evaluate the association between anticholinergic burden and POD. ResultsPOD was observed in 210 of 899 patients (23.4%). Both ARS and ABS were independently associated with POD. The association persisted after adjustment for relevant confounding factors such as age, sex, comorbidities, preoperative cognitive and physical status, number of prescribed drugs, surgery time, type of surgery and anesthesia, usage of heart-lung-machine, and treatment in intensive care unit. If a patient was taking one of the 56 drugs listed in the ABS, risk for POD was 2.7-fold higher (OR = 2.74, 95% CI = 1.55-4.94) and 1.5-fold higher per additional point on the ARS (OR = 1.54, 95% CI = 1.15-2.02). ConclusionPreoperative anticholinergic drug exposure measured by ARS or ABS was independently associated with POD in older patients undergoing elective surgery. Therefore, identification, discontinuation or substitution of anticholinergic medication prior to surgery may be a promising approach to reduce the risk of POD in older patients.
Organic carbon (OC) stored in Arctic permafrost represents one of Earth's largest and most vulnerable terrestrial carbon pools. Amplified climate warming across the Arctic results in widespread permafrost thaw. Permafrost deposits exposed at river cliffs and coasts are particularly susceptible to thawing processes. Accelerating erosion of terrestrial permafrost along shorelines leads to increased transfer of organic matter (OM) to nearshore waters. However, the amount of terrestrial permafrost carbon and nitrogen as well as the OM quality in these deposits is still poorly quantified. We define the OM quality as the intrinsic potential for further transformation, decomposition and mineralisation. Here, we characterise the sources and the quality of OM supplied to the Lena River at a rapidly eroding permafrost river shoreline cliff in the eastern part of the delta (Sobo-Sise Island). Our multi-proxy approach captures bulk elemental, molecu- lar geochemical and carbon isotopic analyses of Late Pleistocene Yedoma permafrost and Holocene cover deposits, discontinuously spanning the last similar to 52 kyr. We showed that the ancient permafrost exposed in the Sobo-Sise cliff has a high organic carbon content (mean of about 5 wt %). The oldest sediments stem from Marine Isotope Stage (MIS) 3 interstadial deposits (dated to 52 to 28 cal ka BP) and are overlaid by last glacial MIS 2 (dated to 28 to 15 cal ka BP) and Holocene MIS 1 (dated to 7-0 cal ka BP) deposits. The relatively high average chain length (ACL) index of n-alkanes along the cliff profile indicates a predominant contribution of vascular plants to the OM composition. The elevated ratio of isoand anteiso-branched fatty acids (FAs) relative to mid- and long-chain (C >= 20) n-FAs in the interstadial MIS 3 and the interglacial MIS 1 deposits suggests stronger microbial activity and consequently higher input of bacterial biomass during these climatically warmer periods. The overall high carbon preference index (CPI) and higher plant fatty acid (HPFA) values as well as high C/N ratios point to a good quality of the preserved OM and thus to a high potential of the OM for decomposition upon thaw. A decrease in HPFA values downwards along the profile probably indicates stronger OM decomposition in the oldest (MIS 3) deposits of the cliff. The characterisation of OM from eroding permafrost leads to a better assessment of the greenhouse gas potential of the OC released into river and nearshore waters in the future.
Massive stars that become stripped of their hydrogen envelope through binary interaction or winds can be observed either as Wolf-Rayet stars, if they have optically thick winds, or as transparent-wind stripped-envelope stars. We approximate their evolution through evolutionary models of single helium stars, and compute detailed model grids in the initial mass range 1.5-70 M. for metallicities between 0.01 and 0.04, from core helium ignition until core collapse. Throughout their lifetimes some stellar models expose the ash of helium burning. We propose that models that have nitrogen-rich envelopes are candidate WN stars, while models with a carbon-rich surface are candidate WC stars during core helium burning, and WO stars afterwards. We measure the metallicity dependence of the total lifetimes of our models and the duration of their evolutionary phases. We propose an analytic estimate of the wind's optical depth to distinguish models of Wolf-Rayet stars from transparent-wind stripped-envelope stars, and find that the luminosity ranges at which WN-, WC-, and WO-type stars can exist is a strong function of metallicity. We find that all carbon-rich models produced in our grids have optically thick winds and match the luminosity distribution of observed populations. We construct population models and predict the numbers of transparent-wind stripped-envelope stars and Wolf-Rayet stars, and derive their number ratios at different metallicities. We find that as metallicity increases, the number of transparent-wind stripped-envelope stars decreases and the number of Wolf-Rayet stars increases. At high metallicities WC- and WO-type stars become more common. We apply our population models to nearby galaxies, and find that populations are more sensitive to the transition luminosity between Wolf-Rayet stars and transparent-wind helium stars than to the metallicity-dependent mass loss rates.
Die ›Klage der Kunst‹ Konrads wird auf dem Hintergrund und in Bezug zur Sangspruchdichtung sowie der Textfamilie allegorischer Erzählungen in der ersten Person untersucht. Während Strophik, Sangbarkeit und kunst-Thematik das Werk in den Kontext der Sangspruchdichtung rücken, stellt es sich durch seinen Umfang, seine Narrativität und das Erzähltempus, das die Handlung zwar nicht dominiert, aber rahmt, an die Seite erster früher Erzählexperimente, die Dialog, Streit oder Rede als erlebte Erfahrung eines Ich präsentieren wie das ›Frauenbuch‹ Ulrichs von Liechtenstein, das aber – ähnlich wie Konrads ›Klage der Kunst‹ – zu seiner Zeit offenbar nur mäßig erfolgreich, jedenfalls nur unikal überliefert, ist. Konrad scheint der erste zu sein, der in der höfischen Literatur das Erzählen in der ersten Person mit Allegorizität verknüpft. Er nutzt dieses neue und in der späteren Literatur so überaus fruchtbare Erzählformat geschickt, um seine eigene literarische Meisterschaft unter anderem in den Gestalten von wildekeit und kunst unter Beweis zu stellen, zu thematisieren und szenisch zu verhandeln.
Arctic river deltas and deltaic near-shore zones represent important land-ocean transition zones influencing sediment dynamics and nutrient fluxes from permafrost-affected terrestrial ecosystems into the coastal Arctic Ocean. To accurately model fluvial carbon and freshwater export from rapidly changing river catchments as well as assess impacts of future change on the Arctic shelf and coastal ecosystems, we need to understand the sea floor characteristics and topographic variety of the coastal zones. To date, digital bathymetrical data from the poorly accessible, shallow, and large areas of the eastern Siberian Arctic shelves are sparse. We have digitized bathymetrical information for nearly 75 000 locations from large-scale (1 V 25000-1 V 500000) current and historical nautical maps of the Lena Delta and the Kolyma Gulf region in northeastern Siberia. We present the first detailed and seamless digital models of coastal zone bathymetry for both delta and gulf regions in 50 and 200m spatial resolution. We validated the resulting bathymetry layers using a combination of our own water depth measurements and a collection of available depth measurements, which showed a strong correlation (r>0.9). Our bathymetrical models will serve as an input for a high-resolution coupled hydrodynamic-ecosystem model to better quantify fluvial and coastal carbon fluxes to the Arctic Ocean, but they may be useful for a range of other studies related to Arctic delta and near-shore dynamics such as modeling of submarine permafrost, near-shore sea ice, or shelf sediment transport. The new digital high-resolution bathymetry products are available on the PANGAEA data set repository for the Lena Delta (https://doi.org/10.1594/PANGAEA.934045; Fuchs et al., 2021a) and Kolyma Gulf region (https://doi.org/10.1594/PANGAEA.934049; Fuchs et al., 2021b), respectively. Likewise, the depth validation data are available on PANGAEA as well (https://doi.org/10.1594/PANGAEA.933187; Fuchs et al., 2021c).
The formation, growth and drainage of lakes in Arctic and boreal lowland permafrost regions influence landscape and ecosystem processes. These lake and drained lake basin (L-DLB) systems occupy >20% of the circumpolar Northern Hemisphere permafrost region and similar to 50% of the area below 300 m above sea level. Climate change is causing drastic impacts to L-DLB systems, with implications for permafrost dynamics, ecosystem functioning, biogeochemical processes and human livelihoods in lowland permafrost regions. In this Review, we discuss how an increase in the number of lakes as a result of permafrost thaw and an intensifying hydrologic regime are not currently offsetting the land area gained through lake drainage, enhancing the dominance of drained lake basins (DLBs).The contemporary transition from lakes to DLBs decreases hydrologic storage, leads to permafrost aggradation, increases carbon sequestration and diversifies the shifting habitat mosaic in Arctic and boreal regions. However, further warming could inhibit permafrost aggradation in DLBs, disrupting the trajectory of important microtopographic controls on carbon fluxes and ecosystem processes in permafrost-region L-DLB systems. Further research is needed to understand the future dynamics of L-DLB systems to improve Earth system models, permafrost carbon feedback assessments, permafrost hydrology linkages, infrastructure development in permafrost regions and the well-being of northern socio-ecological systems.