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Anaemia is a risk factor for several adverse postoperative outcomes. Detailed data about the prevalence of anaemia are not available over a long time-period in Germany. In this retrospective, observational, multicentre study, patients undergoing surgery in March in 2007, 2012, 2015, 2017 and 2019 were studied. The primary objective was the prevalence of anaemia at hospital admission. The secondary objectives were the association between anaemia and the number of units of red blood cells transfused, length of hospital stay and in-hospital mortality. A total of 23,836 patients were included from eight centres. The prevalence of pre-operative anaemia in patients aged ≥ 18 years decreased slightly from 37% in 2007 to 32.5% in 2019 (p = 0.01) and increased in patients aged ≤ 18 years from 18.8% in 2007 to 26.4% in 2019 (p > 0.001). The total amount of blood administered per 1000 patients decreased from 671.2 units in 2007 to 289.0 units in 2019. Transfusion rates in anaemic patients declined from 33.8% in 2007 to 19.1% in 2019 (p < 0.001) and in non-anaemic patients from 8.4% in 2007 to 3.4% in 2019 (p < 0.001). Overall, the mortality rate remained constant over the years: 2.9% in 2007, 2.1% in 2012, 2.5% in 2015, 1.9% in 2017 and 2.5% in 2019. In the presence of anaemia, mortality was significantly increased compared with patients without anaemia (OR 5.27 (95%CI 4.13–6.77); p < 0.001). Red blood cell transfusion was associated with an increased risk of mortality (OR 14.98 (95%CI 11.83–19.03); p < 0.001). Using multivariable linear regression analysis with fixed effects, we found that pre-operative anaemia (OR 2.08 (95%CI 1.42–3.05); p < 0.001) and red blood cell transfusion (OR 4.29 (95%CI 3.09–5.94); p < 0.001) were predictors of mortality but not length of stay (0.99 (95%CI 0.98–1.00) days; p = 0.12) and analysed years (2007 vs. 2019: OR 1.49 (95%CI 0.86–2.69); p = 0.07). Pre-operative anaemia affects more than 30% of surgical patients in Germany and multidisciplinary action is urgently required to reduce adverse outcomes.
Both nerve injury and complex regional pain syndrome (CRPS) can result in chronic pain. In traumatic neuropathy, the blood nerve barrier (BNB) shielding the nerve is impaired—partly due to dysregulated microRNAs (miRNAs). Upregulation of microRNA-21-5p (miR-21) has previously been documented in neuropathic pain, predominantly due to its proinflammatory features. However, little is known about other functions. Here, we characterized miR-21 in neuropathic pain and its impact on the BNB in a human-murine back translational approach. MiR-21 expression was elevated in plasma of patients with CRPS as well as in nerves of mice after transient and persistent nerve injury. Mice presented with BNB leakage, as well as loss of claudin-1 in both injured and spared nerves. Moreover, the putative miR-21 target RECK was decreased and downstream Mmp9 upregulated, as was Tgfb. In vitro experiments in human epithelial cells confirmed a downregulation of CLDN1 by miR-21 mimics via inhibition of the RECK/MMP9 pathway but not TGFB. Perineurial miR-21 mimic application in mice elicited mechanical hypersensitivity, while local inhibition of miR-21 after nerve injury reversed it. In summary, the data support a novel role for miR-21, independent of prior inflammation, in elicitation of pain and impairment of the BNB via RECK/MMP9.
Background
Complex regional pain syndrome (CRPS) is an orphan disease occurring as a complication after trauma. Due to its acute onset and the typical clinical presentation of the inflammatory and autonomous signs, it is an eye-catching chronic pain disease affecting also young and working people. In social media and the internet, high pain severity and the unfavourable prognosis are often empathized.
Methods
Here, we compared epidemiological, pain and lifestyle factors of 223 CPRS patients from the “ncRNAPain” cohort with 255 patients with chronic musculoskeletal pain (MSK). MSK patients were recruited at the beginning of a multimodal pain therapy programme. We searched for factors predicting pain intensity.
Results
Both chronic pain diseases affected women in middle age. Patients with MSK were more obese, drank more alcohol, and were less educated (Pearson chi-square Test or Mann–Whitney/U-Test). Both groups smoked more than healthy people in the OECD (Organization for Economic Cooperation and Development). Mann–Whitney/U-Test confirmed that CRPS patients did not have more severe pain and did not suffer more from pain-related disability than patients with MSK. CRPS patients also had less psychiatric comorbidities. Multiple linear regression analysis revealed that group assignment, depressive characteristics, body mass index, average alcohol consumption and smoking predicted higher pain ratings, while disease duration, anxiety symptoms or gender had no influence on pain intensity.
Conclusion
In summary, our study supports a more optimistic view on pain in CRPS patients in comparison to MSK and identifies lifestyle factors that might contribute to the pathophysiology like smoking and drinking. Important next steps are the identification of CRPS patients at risk for chronification or—vice versa—with protective factors for pain resolution.
Significance
This study compares complex regional pain syndrome (CRPS) and chronic musculoskeletal pain and questions previously reported pain, disability and lifestyle factors associated with CRPS.
Stalk cell polar ion transport provide for bladder‐based salinity tolerance in Chenopodium quinoa
(2022)
Chenopodium quinoa uses epidermal bladder cells (EBCs) to sequester excess salt. Each EBC complex consists of a leaf epidermal cell, a stalk cell, and the bladder.
Under salt stress, sodium (Na\(^{+}\)), chloride (Cl\(^{−}\)), potassium (K\(^{+}\)) and various metabolites are shuttled from the leaf lamina to the bladders. Stalk cells operate as both a selectivity filter and a flux controller.
In line with the nature of a transfer cell, advanced transmission electron tomography, electrophysiology, and fluorescent tracer flux studies revealed the stalk cell’s polar organization and bladder‐directed solute flow.
RNA sequencing and cluster analysis revealed the gene expression profiles of the stalk cells. Among the stalk cell enriched genes, ion channels and carriers as well as sugar transporters were most pronounced. Based on their electrophysiological fingerprint and thermodynamic considerations, a model for stalk cell transcellular transport was derived.
Purpose
Fungal biomarkers support early diagnosis of invasive fungal infections. In this study, we evaluated the impact of a recent update to the manufacturer‐recommended cut‐off for beta‐1,3‐D‐glucan (BDG) testing (Fujifilm Wako BDG assay) on sensitivity and specificity for the detection of candidemia. Additionally, we compared the performance with tests for Candida antigen (Ag by Serion ELISA antigen Candida, Virion\Serion) and anti‐mannan antibodies (Ab by Hemkit Candida IHA, Ravo Diagnostika).
Methods
Sera of 82 patients with candidemia, which were sampled with a maximum distance of ±14 days from the date of sampling of the corresponding positive blood cultures, were retrospectively analysed for BDG, Ag and Ab. Results of BDG testing were compared with results from sera of 129 patients with candidemia from a different hospital.
Results
Sensitivity of BDG testing (47%) was higher than for Ag (17%) or Ab (20%). By combining Ag and Ab testing, sensitivity was raised to 32%. Lowering the cut‐off of BDG from 11 pg/ml to the newly recommended cut‐off of 7 pg/ml resulted in a significant increase in sensitivity (47% vs 58%, p = .01 and 63% vs 71% p < .01). At both centres, the increase was significant in NAC but not in C. albicans candidemia. No significant effects on specificity were observed.
Conclusion
BDG testing outperformed Ag and Ab testing and its combination. Lowering the BDG cut‐off had no significant impact on specificity. The increase in sensitivity can be mainly attributed to a gain in sensitivity for non‐albicans Candida species bloodstream infections.
Aseptic loosening of total hip and knee joint replacements is the most common indication for revision surgery after primary hip and knee arthroplasty. Research suggests that exposure and uptake of wear by mesenchymal stromal cells (MSC) and macrophages results in the secretion of proinflammatory cytokines and local osteolysis, but also impaired cell viability and regenerative capacity of MSC. Therefore, this in vitro study compared the regenerative and differentiation capacity of MSC derived from patients undergoing primary total hip arthroplasty (MSCprim) to MSC derived from patients undergoing revision surgery after aseptic loosening of total hip and knee joint implants (MSCrev). Regenerative capacity was examined by measuring the cumulative population doubling (CPD) in addition to the number of passages until cells stopped proliferating. Osteogenesis and adipogenesis in monolayer cultures were assessed using histological stainings. Furthermore, RT‐PCR was performed to evaluate the relative expression of osteogenic and adipogenic marker genes as well as the expression of markers for a senescence‐associated secretory phenotype (SASP). MSCrev possessed a limited regenerative capacity in comparison to MSCprim. Interestingly, MSCrev also showed an impaired osteogenic and adipogenic differentiation capacity compared to MSCprim and displayed a SASP early after isolation. Whether this is the cause or the consequence of the aseptic loosening of total joint implants remains unclear. Future research should focus on the identification of specific cell markers on MSCprim, which may influence complication rates such as aseptic loosening of total joint arthroplasty to further individualize and optimize total joint arthroplasty.
Activating Organic Phosphorescence via Heavy Metal–π Interaction Induced Intersystem Crossing
(2022)
Heavy‐atom‐containing clusters, nanocrystals, and other semiconductors can sensitize the triplet states of their surface‐bonded chromophores, but the energy loss, such as nonradiative deactivation, often prevents the synergistic light emission in their solid‐state coassemblies. Cocrystallization allows new combinations of molecules with complementary properties for achieving functionalities not available in single components. Here, the cocrystal formation that employs platinum(II) acetylacetonate (Pt(acac)\(_{2}\)) as a triplet sensitizer and electron‐deficient 1,4,5,8‐naphthalene diimides (NDIs) as organic phosphors is reported. The hybrid cocrystals exhibit room‐temperature phosphorescence confined in the low‐lying, long‐lived triplet state of NDIs with photoluminescence (PL) quantum yield (Φ\(_{PL}\)) exceeding 25% and a phosphorescence lifetime (τ\(_{Ph}\)) of 156 µs. This remarkable PL property benefits from the noncovalent electronic and spin–orbital coupling between the constituents.
Green plants are equipped with photoreceptors that are capable of sensing radiation in the ultraviolet‐to‐blue and the red‐to‐far‐red parts of the light spectrum. However, plant cells are not particularly sensitive to green light (GL), and light which lies within this part of the spectrum does not efficiently trigger the opening of stomatal pores. Here, we discuss the current knowledge of stomatal responses to light, which are either provoked via photosynthetically active radiation or by specific blue light (BL) signaling pathways. The limited impact of GL on stomatal movements provides a unique option to use this light quality to control optogenetic tools. Recently, several of these tools have been optimized for use in plant biological research, either to control gene expression, or to provoke ion fluxes. Initial studies with the BL‐activated potassium channel BLINK1 showed that this tool can speed up stomatal movements. Moreover, the GL‐sensitive anion channel GtACR1 can induce stomatal closure, even at conditions that provoke stomatal opening in wild‐type plants. Given that crop plants in controlled‐environment agriculture and horticulture are often cultivated with artificial light sources (i.e. a combination of blue and red light from light‐emitting diodes), GL signals can be used as a remote‐control signal that controls stomatal transpiration and water consumption.
Objective
Global challenges such as climate change or the COVID‐19 pandemic have drawn public attention to conspiracy theories and citizens' non‐compliance to science‐based behavioral guidelines. We focus on individuals' worldviews about how one can and should construct reality (epistemic beliefs) to explain the endorsement of conspiracy theories and behavior during the COVID‐19 pandemic and propose the Dark Factor of Personality (D) as an antecedent of post‐truth epistemic beliefs.
Method and Results
This model is tested in four pre‐registered studies. In Study 1 (N = 321), we found first evidence for a positive association between D and post‐truth epistemic beliefs (Faith in Intuition for Facts, Need for Evidence, Truth is Political). In Study 2 (N = 453), we tested the model proper by further showing that post‐truth epistemic beliefs predict the endorsement of COVID‐19 conspiracies and disregarding COVID‐19 behavioral guidelines. Study 3 (N = 923) largely replicated these results at a later stage of the pandemic. Finally, in Study 4 (N = 513), we replicated the results in a German sample, corroborating their cross‐cultural validity. Interactions with political orientation were observed.
Conclusion
Our research highlights that epistemic beliefs need to be taken into account when addressing major challenges to humankind.
Aim
This study evaluated the oral health status of adult patients with hypophosphatasia (HPP).
Materials and Methods
Parameters of oral health assessment comprised decayed/missing/filled teeth (DMFT) index, probing pocket depth and clinical attachment level (CAL) as well as documentation of tooth loss and periodontal health status according to CCD/AAP criteria. Findings were compared with national reference data (DMS V survey) reporting oral health status in age‐related controls. Within‐group comparisons were made between the HPP patients harbouring one versus two alkaline phosphatase liver/bone/kidney type (ALPL) gene variants.
Results
Of 80 HPP patients (64 female) with a mean age of 46.4 years (range 24–78) and one (n = 55) or two (n = 18) variants (n = 7 lacking testing) within the ALPL gene, those with two variants displayed substantially higher tooth loss rate (14.0 ± 9.3) than those affected by only one ALPL variant (4.1 ± 5.4), who did not differ substantially from healthy DMS V controls. While DMFT score and severe periodontal diseases (PDs) of HPP patients with one variant only increased with progressing age, the two‐variant sub‐cohort age independently exhibited increased DMFT scores and a higher rate of severe PDs.
Conclusions
HPP patients affected by two variants of the ALPL gene exhibited a higher risk of periodontitis and tooth loss than the general population, while patients with one variant developed clinically relevant oral disease symptoms with progressing ageing.
Recent reports on insect decline have highlighted the need for long‐term data on insect communities towards identifying their trends and drivers.
With the launch of many new insect monitoring schemes to investigate insect communities over large spatial and temporal scales, Malaise traps have become one of the most important tools due to the broad spectrum of species collected and reduced capture bias through passive sampling of insects day and night. However, Malaise traps can vary in size, shape, and colour, and it is unknown how these differences affect biomass, species richness, and composition of trap catch, making it difficult to compare results between studies.
We compared five Malaise trap types (three variations of the Townes and two variations of the Bartak Malaise trap) to determine their effects on biomass and species richness as identified by metabarcoding.
Insect biomass varied by 20%–55%, not strictly following trap size but varying with trap type. Total species richness was 20%–38% higher in the three Townes trap models compared to the Bartak traps. Bartak traps captured lower richness of highly mobile taxa but increased richness of ground‐dwelling taxa. The white roofed Townes trap captured a higher richness of pollinators.
We find that biomass, total richness, and taxa group specific richness are all sensitive to Malaise trap type. Trap type should be carefully considered and aligned to match monitoring and research questions. Additionally, our estimates of trap type effects can be used to adjust results to facilitate comparisons across studies.
Increase in lower limb strength after multimodal pain management in patients with low back pain
(2022)
Background and Objectives: The aim of the present study was to evaluate the efficacy of a multimodal pain therapy (MPM) regarding the objective parameter muscle strength of segment-dependent lower limb muscle groups before and after such a treatment. Materials and Methods: 52 patients with a history of low back pain and/or leg pain received standardized multimodal pain management. Strength of segment indicating lower limb muscles were assessed for each patient before and after ten days of treatment by handheld dynamometry. Results: Overall strength increased significantly from 23.6 kg ± 6.6 prior to treatment to 25.4 ± 7.3 after treatment, p ≤ 0.001. All muscle groups significantly increased in strength with exception of great toe extensors. Conclusions: Despite lower basic strength values at the beginning of treatment, all investigated muscle groups, except for the great toe extensors, showed a significant increase of overall strength after completion of the multimodal pain management concept. Increased overall strength could help with avoiding further need of medical care by supporting patients’ autonomy in daily life activities, as well as maintaining working abilities. Thus, our study is the first to show a significant positive influence on lower limb strength in patients with low back pain after a conservative MPM program.
The exponential increase in the human population in tandem with increased food demand has caused agriculture to be the global‐dominant form of land use. Afrotropical drylands are currently facing the loss of natural savannah habitats and agricultural intensification with largely unknown consequences for bees. Here we investigate the effects of agricultural intensification on bee assemblages in the Afrotropical drylands of northern Tanzania. We disentangled the direct effects of agricultural intensification and temperature on bee richness from indirect effects mediated by changes in floral resources.
We collected data from 24 study sites representing three levels of management intensity (natural savannah, moderate intensive and highly intensive agriculture) spanning an extensive gradient of mean annual temperature (MAT) in northern Tanzania. We used ordinary linear models and path analysis to test the effects of agricultural intensity and MAT on bee species richness, bee species composition and body‐size variation of bee communities.
We found that bee species richness increased with agricultural intensity and with increasing temperature. The effects of agricultural intensity and temperature on bee species richness were mediated by the positive effects of agriculture and temperature on the richness of floral resources used by bees. During the off‐growing season, agricultural land was characterized by an extensive period of fallow land holding a very high density of flowering plants with unique bee species composition. The increase in bee diversity in agricultural habitats paralleled an increasing variation of bee body sizes with agricultural intensification that, however, diminished in environments with higher temperatures.
Synthesis and applications. Our study reveals that bee assemblages in Afrotropical drylands benefit from agricultural intensification in the way it is currently practiced. However, further land‐use intensification, including year‐round irrigated crop monocultures and excessive use of agrochemicals, is likely to exert a negative impact on bee diversity and pollination services, as reported in temperate regions. Moreover, several bee species were restricted to natural savannah habitats. To conserve bee communities and guarantee pollination services in the region, a mixture of savannah and agriculture, with long periods of fallow land should be maintained.
The mechanisms by which climatic changes influence ecosystem functions, that is, by a direct climatic control of ecosystem processes or by modifying richness and trait compositions of species communities, remain unresolved.
This study is a contribution to this discourse by elucidating the linkages between climate, land use, biodiversity, body size and ecosystem functions.
We disentangled direct climatic from biodiversity‐mediated effects by using dung removal by dung beetles as a model system and by combining correlative field data and exclosure experiments along an extensive elevational gradient on Mt. Kilimanjaro, Tanzania.
Dung removal declined with increasing elevation, being associated with a strong reduction in the richness and body size traits of dung beetle communities. Climate influenced dung removal rates by modifying biodiversity rather than by direct effects. The biodiversity–ecosystem effect was driven by a change in the mean body size of dung beetles. Dung removal rates were strongly reduced when large dung beetles were experimentally excluded.
This study underscores that climate influences ecosystem functions mainly by modifying biodiversity and underpins the important role of body size for dung removal.
Bivariate copula monitoring
(2022)
The assumption of multivariate normality underlying the Hotelling T\(^{2}\) chart is often violated for process data. The multivariate dependency structure can be separated from marginals with the help of copula theory, which permits to model association structures beyond the covariance matrix. Copula‐based estimation and testing routines have reached maturity regarding a variety of practical applications. We have constructed a rich design matrix for the comparison of the Hotelling T\(^{2}\) chart with the copula test by Verdier and the copula test by Vuong, which allows for weighting the observations adaptively. Based on the design matrix, we have conducted a large and computationally intensive simulation study. The results show that the copula test by Verdier performs better than Hotelling T\(^{2}\) in a large variety of out‐of‐control cases, whereas the weighted Vuong scheme often fails to provide an improvement.
We quantify the contemporaneous relationships among stock markets in the euro area, the United States, and a group of emerging economies over the period from 2008 to 2017. Exploiting the heteroskedasticity in the stock market data, we identify shocks that originated in the respective domestic markets and shocks that are common to all markets. Our results underline the leading role of the United States in international equity markets, but also point to the importance of indirect spillovers for all economies. Variance decompositions show that while domestic shocks explain the bigger part of the variation in each stock market, a substantial part of the variation in the euro area and the emerging economies can be attributed to foreign shocks. A comparison with a sample covering the pre‐crisis period from 1999 to 2007 suggests a strengthening of the linkages among global stock markets in recent years. In particular, the spillovers from advanced to emerging economies have become more pronounced.
A study on the reactivity of N‐heterocyclic carbenes (NHCs) and the cyclic (alkyl)(amino)carbene cAAC\(^{Me}\) with selected germanium(IV) and tin(IV) chlorides and organyl chlorides is presented. The reactions of the NHCs Me\(_{2}\)Im\(^{Me}\), iPr\(_{2}\)Im\(^{Me}\) and Dipp2Im with the methyl chlorides ECl\(_{2}\)Me\(_{2}\) afforded the adducts NHC ⋅ ECl\(_{2}\)Me\(_{2}\) (E=Ge (1), Sn (2)), NHC=Me\(_{2}\)Im\(^{Me}\) (a), iPr\(_{2}\)Im\(^{Me}\) (b), Dipp\(_{2}\)Im (c)). The reaction of Me2Im\(^{Me}\) with GeCl\(_{4}\) led to isolation of Me\(_{2}\)Im\(^{Me}\) ⋅ GeCl\(_{4}\) (3), the reaction of iPr\(_{2}\)Im\(^{Me}\) with SnCl\(_{4}\) in THF afforded the THF adduct iPr\(_{2}\)Im\(^{Me}\) ⋅ SnCl\(_{4}\) ⋅ THF (4). Dipp\(_{2}\)Im ⋅ GeCl\(_{2}\)Me\(_{2}\) (1 c) isomerized into the backbone coordinated imidazolium salt [aDipp\(_{2}\)Im ⋅ GeClMe\(_{2}\)][Cl] (5) upon thermal treatment. The reactions of cAAC\(^{Me}\) with (i) ECl\(_{2}\)R\(_{2}\) (E=Ge, Sn) gave the adducts cAAC\(^{Me}\) ⋅ ECl\(_{2}\)R\(_{2}\) (R=Me: E=Ge (6); Sn (7); Ph: E=Ge (8)), with (ii) GeClMe\(_{3}\) and GeCl\(_{4}\) the salts [cAAC\(^{Me}\) ⋅ GeMe\(_{3}\)][Cl] (9) and [cAACMeCl][GeCl\(_{3}\)] (10), and (iii) with SnCl\(_{4}\) the salt [cAACMeCl][SnCl\(_{3}\)] (11) and the adduct cAAC\(^{Me}\) ⋅ SnCl\(_{4}\) (12). Reduction of 2 a with KC\(_{8}\) afforded the NHC‐stabilized stannylene Me\(_{2}\)Im\(^{Me}\) ⋅ SnMe\(_{2}\) 13, reduction of 7 with either KC8 or 1,4‐bis‐(trimethylsilyl)‐1,4‐dihydropyrazin in the presence of SnCl\(_{2}\)Me\(_{2}\) yielded cAAC\(^{Me}\) ⋅ SnMe\(_{2}\) ⋅ SnMe\(_{2}\)Cl\(_{2}\) (14).
A series of five new homoleptic, linear nickel d\(^{9}\)‐complexes of the type [Ni\(^{I}\)(NHC)\(_{2}\)]\(^{+}\) is reported. Starting from the literature known Ni(0) complexes [Ni(Mes\(_{2}\)Im)\(_{2}\)] 1, [Ni(Mes\(_{2}\)Im\(^{H2}\))2] 2, [Ni(Dipp\(_{2}\)Im)\(_{2}\)] 3, [Ni(Dipp\(_{2}\)Im\(^{H2}\))\(_{2}\)] 4 and [Ni(cAAC\(^{Me}\))\(_{2}\)] 5 (Mes\(_{2}\)Im=1,3‐bis(2,4,6‐trimethylphenyl)‐imidazolin‐2‐ylidene, Mes\(_{2}\)Im\(^{H2}\)=1,3‐bis(2,4,6‐trimethylphenyl)‐imidazolidin‐2‐ylidene, Dipp\(_{2}\)Im=1,3‐bis(2,6‐diisopropylphenyl)‐imidazolin‐2‐ylidene, Dipp\(_{2}\)Im\(^{H2}\)=1,3‐bis(2,6‐diisopropylphenyl)‐imidazolidin‐2‐ylidene, cAAC\(^{Me}\)=1‐(2,6‐diisopropylphenyl)‐3,3,5,5‐tetramethylpyrrolidin‐2‐yliden), their oxidized Ni(I) analogues [Ni\(^{I}\)(Mes\(_{2}\)Im)\(_{2}\)][BPh\(_{4}\)] 1\(^{+}\), [Ni\(^{I}\)(Mes\(_{2}\)Im\(^{H2}\))\(_{2}\)][BPh\(_{4}\)] 2\(^{+}\), [Ni\(^{I}\)(Dipp\(_{2}\)Im)\(_{2}\)][BPh\(_{4}\)] 3\(^{+}\), [Ni\(^{I}\)(Dipp\(_{2}\)Im\(^{H2}\))\(_{2}\)][BPh\(_{4}\)] 4\(^{+}\) and [Ni\(^{I}\)(cAAC\(^{Me}\))\(_{2}\)][BPh\(_{4}\)] 5\(^{+}\) were synthesized by one‐electron oxidation with ferrocenium tetraphenyl‐borate. The complexes 1\(^{+}\)–5\(^{+}\) were fully characterized including X‐ray structure analysis. The complex cations reveal linear geometries in the solid state and NMR spectra with extremely broad, paramagnetically shifted resonances. DFT calculations predicted an orbitally degenerate ground state leading to large magnetic anisotropy, which was verified by EPR measurements in solution and on solid samples. The magnetic anisotropy of the complexes is highly dependent from the steric protection of the metal atom, which results in a noticeable decrease of the g‐tensor anisotropy for the N‐Mes substituted complexes 1\(^{+}\) and 2\(^{+}\) in solution due to the formation of T‐shaped THF adducts.
The development of two conventional dendritic cells (DC) subsets (cDC1 and cDC2) and the plasmacytoid DC (pDC) in vivo and in cultures of bone marrow (BM) cells is mediated by the growth factor Flt3L. However, little is known about the factors that direct the development of the individual DC subsets. Here, we describe the selective in vitro generation of murine ESAM\(^{low}\) CD103\(^{-}\) XCR1\(^{-}\) CD172a\(^{+}\) CD11b\(^{+}\) cDC2 from BM by treatment with a combination of Flt3L, LIF, and IL‐10 (collectively named as FL10). FL10 promotes common dendritic cell progenitors (CDP) proliferation in the cultures, similar to Flt3L and CDP sorted and cultured in FL10 generate exclusively cDC2. These cDC2 express the transcription factors Irf4, Klf4, and Notch2, and their growth is reduced using BM from Irf4\(^{-/-}\) mice, but the expression of Batf3 and Tcf4 is low. Functionally they respond to TLR3, TLR4, and TLR9 signals by upregulation of the surface maturation markers MHC II, CD80, CD86, and CD40, while they poorly secrete proinflammatory cytokines. Peptide presentation to TCR transgenic OT‐II cells induced proliferation and IFN‐γ production that was similar to GM‐CSF‐generated BM‐DC and higher than Flt3L‐generated DC. Together, our data support that FL10 culture of BM cells selectively promotes CDP‐derived ESAM\(^{low}\) cDC2 (cDC2B) development and survival in vitro.
Environmental gradients generate and maintain biodiversity on Earth. Mountain slopes are among the most pronounced terrestrial environmental gradients, and the elevational structure of species and their interactions can provide unique insight into the processes that govern community assembly and function in mountain ecosystems. We recorded bumble bee–flower interactions over 3 years along a 1400‐m elevational gradient in the German Alps. Using nonlinear modeling techniques, we analyzed elevational patterns at the levels of abundance, species richness, species β‐diversity, and interaction β‐diversity. Though floral richness exhibited a midelevation peak, bumble bee richness increased with elevation before leveling off at the highest sites, demonstrating the exceptional adaptation of these bees to cold temperatures and short growing seasons. In terms of abundance, though, bumble bees exhibited divergent species‐level responses to elevation, with a clear separation between species preferring low versus high elevations. Overall interaction β‐diversity was mainly caused by strong turnover in the floral community, which exhibited a well‐defined threshold of β‐diversity rate at the tree line ecotone. Interaction β‐diversity increased sharply at the upper extreme of the elevation gradient (1800–2000 m), an interval over which we also saw steep decline in floral richness and abundance. Turnover of bumble bees along the elevation gradient was modest, with the highest rate of β‐diversity occurring over the interval from low‐ to mid‐elevation sites. The contrast between the relative robustness bumble bee communities and sensitivity of plant communities to the elevational gradient in our study suggests that the strongest effects of climate change on mountain bumble bees may be indirect effects mediated by the responses of their floral hosts, though bumble bee species that specialize in high‐elevation habitats may also experience significant direct effects of warming.