bluuebunny/crossref_metadata_2025_split huggingface dataset:
IL-33-ST2 axis regulates myeloid cell differentiation and activation enabling effective club cell regeneration
Authors: Dagher Rania , Copenhaver Alan M. , Besnard Valerie , Berlin Aaron , Hamidi Fatima , Maret Marielle , Wang Jingya , Qu Xiaotao , Shrestha Yashaswi , Wu Jincheng , Gautier Gregory , Raja Rajiv , Aubier Michel , Kolbeck Roland , Humbles Alison A. , Pretolani Marina 
Published: September 2020

AbstractEvidence points to an indispensable function of macrophages in tissue regeneration, yet the underlying molecular mechanisms remain elusive. Here we demonstrate a protective function for the IL-33-ST2 axis in bronchial epithelial repair, and implicate ST2 in myeloid cell differentiation. ST2 deficiency in mice leads to reduced lung myeloid cell infiltration, abnormal alternatively activated macrophage (AAM) function, and impaired epithelial repair post naphthalene-induced injury. Reconstitution of wild type (WT) AAMs to ST2-deficient mice completely restores bronchial re-epithelialization. Central to this mechanism is the direct effect of IL-33-ST2 signaling on monocyte/macrophage differentiation, self-renewal and repairing ability, as evidenced by the downregulation of key pathways regulating myeloid cell cycle, maturation and regenerative function of the epithelial niche in ST2−/−mice. Thus, the IL-33-ST2 axis controls epithelial niche regeneration by activating a large multi-cellular circuit, including monocyte differentiation into competent repairing AAMs, as well as group-2 innate lymphoid cell (ILC2)-mediated AAM activation.
Enteroendocrine cells couple nutrient sensing to nutrient absorption by regulating ion transport
Authors: McCauley Heather A. , Matthis Andrea L. , Enriquez Jacob R. , Nichol Jonah T. , Sanchez J. Guillermo , Stone William J. , Sundaram Nambirajan , Helmrath Michael A. , Montrose Marshall H. , Aihara Eitaro , Wells James M. 
Published: September 2020

AbstractThe ability to absorb ingested nutrients is an essential function of all metazoans and utilizes a wide array of nutrient transporters found on the absorptive enterocytes of the small intestine. A unique population of patients has previously been identified with severe congenital malabsorptive diarrhea upon ingestion of any enteral nutrition. The intestines of these patients are macroscopically normal, but lack enteroendocrine cells (EECs), suggesting an essential role for this rare population of nutrient-sensing cells in regulating macronutrient absorption. Here, we use human and mouse models of EEC deficiency to identify an unappreciated role for the EEC hormone peptide YY in regulating ion-coupled absorption of glucose and dipeptides. We find that peptide YY is required in the small intestine to maintain normal electrophysiology in the presence of vasoactive intestinal polypeptide, a potent stimulator of ion secretion classically produced by enteric neurons. Administration of peptide YY to EEC-deficient mice restores normal electrophysiology, improves glucose and peptide absorption, diminishes diarrhea and rescues postnatal survival. These data suggest that peptide YY is a key regulator of macronutrient absorption in the small intestine and may be a viable therapeutic option to treat patients with electrolyte imbalance and nutrient malabsorption.
A Cu(II)–ATP complex efficiently catalyses enantioselective Diels–Alder reactions
Authors: Wang Changhao , Qi Qianqian , Li Wenying , Dang Jingshuang , Hao Min , Lv Shuting , Dong Xingchen , Gu Youkun , Wu Peizhe , Zhang Wenyue , Chen Yashao , Hartig Jörg S. 
Published: September 2020

AbstractNatural biomolecules have been used extensively as chiral scaffolds that bind/surround metal complexes to achieve stereoselectivity in catalytic reactions. ATP is ubiquitously found in nature as an energy-storing molecule and can complex diverse metal cations. However, in biotic reactions ATP-metal complexes are thought to function mostly as co-substrates undergoing phosphoanhydride bond cleavage reactions rather than participating in catalytic mechanisms. Here, we report that a specific Cu(II)-ATP complex (Cu2+·ATP) efficiently catalyses Diels-Alder reactions with high reactivity and enantioselectivity. We investigate the substrates and stereoselectivity of the reaction, characterise the catalyst by a range of physicochemical experiments and propose the reaction mechanism based on density functional theory (DFT) calculations. It is found that three key residues (N7, β-phosphate and γ-phosphate) in ATP are important for the efficient catalytic activity and stereocontrol via complexation of the Cu(II) ion. In addition to the potential technological uses, these findings could have general implications for the chemical selection of complex mixtures in prebiotic scenarios.
In situ tuning of electronic structure of catalysts using controllable hydrogen spillover for enhanced selectivity
Authors: Xiong Mi , Gao Zhe , Zhao Peng , Wang Guofu , Yan Wenjun , Xing Shuangfeng , Wang Pengfei , Ma Jingyuan , Jiang Zheng , Liu Xingchen , Ma Jiping , Xu Jie , Qin Yong 
Published: September 2020

AbstractIn situ tuning of the electronic structure of active sites is a long-standing challenge. Herein, we propose a strategy by controlling the hydrogen spillover distance to in situ tune the electronic structure. The strategy is demonstrated to be feasible with the assistance of CoOx/Al2O3/Pt catalysts prepared by atomic layer deposition in which CoOx and Pt nanoparticles are separated by hollow Al2O3 nanotubes. The strength of hydrogen spillover from Pt to CoOx can be precisely tailored by varying the Al2O3 thickness. Using CoOx/Al2O3 catalyzed styrene epoxidation as an example, the CoOx/Al2O3/Pt with 7 nm Al2O3 layer exhibits greatly enhanced selectivity (from 74.3% to 94.8%) when H2 is added. The enhanced selectivity is attributed to the introduction of controllable hydrogen spillover, resulting in the reduction of CoOx during the reaction. Our method is also effective for the epoxidation of styrene derivatives. We anticipate this method is a general strategy for other reactions.
Omega-3 index and blood pressure responses to eating foods naturally enriched with omega-3 polyunsaturated fatty acids: a randomized controlled trial
Authors: Stanton Alice V. , James Kirstyn , Brennan Margaret M. , O’Donovan Fiona , Buskandar Fahad , Shortall Kathleen , El-Sayed Thora , Kennedy Jean , Hayes Heather , Fahey Alan G. , Pender Niall , Thom Simon A. M. , Moran Niamh , Williams David J. , Dolan Eamon 
Published: September 2020

AbstractDiets low in seafood omega-3 polyunsaturated fatty acids (PUFAs) are very prevalent. Such diets have recently been ranked as the sixth most important dietary risk factor—1.5 million deaths and 33 million disability-adjusted life-years worldwide are attributable to this deficiency. Wild oily fish stocks are insufficient to feed the world’s population, and levels of eicosapentaenoic acid and docosahexaenoic acid (DHA) in farmed fish have more than halved in the last 20 years. Here we report on a double-blinded, controlled trial, where 161 healthy normotensive adults were randomly allocated to eat at least three portions/week of omega-3-PUFA enriched (or control) chicken-meat, and to eat at least three omega-3-PUFA enriched (or control) eggs/week, for 6 months. We show that regular consumption of omega-3-PUFA enriched chicken-meat and eggs significantly increased the primary outcome, the red cell omega-3 index (mean difference [98.75% confidence interval] from the group that ate both control foods, 1.7% [0.7, 2.6]). Numbers of subjects with a very high-risk omega-3 index (index < 4%) were more than halved amongst the group that ate both enriched foods. Furthermore, eating the enriched foods resulted in clinically relevant reductions in diastolic blood pressure (− 3.1 mmHg [− 5.8, − 0.3]). We conclude that chicken-meat and eggs, naturally enriched with algae-sourced omega-3-PUFAs, may serve as alternative dietary sources of these essential micronutrients. Unlike many lifestyle interventions, long-term population health benefits do not depend on willingness of individuals to make long-lasting difficult dietary changes, but on the availability of a range of commonly eaten, relatively inexpensive, omega-3-PUFA enriched foods.
Hydrogen-bonded host–guest systems are stable in ionic liquids
Authors: Naranjo Teresa , Álvarez-Asencio Rubén , Pedraz Patricia , Nieto-Ortega Belén , Silva Sara Moreno-Da , Burzurí Enrique , Rutland Mark W. , Pérez Emilio M. 
Published: September 2020

AbstractWe show that H-bonded host–guest systems associate in ionic liquids (ILs), pure salts with melting point below room temperature, in which dipole–dipole electrostatic interactions should be negligible in comparison with dipole-charge interactions. Binding constants (Ka) obtained from titrations of four H-bonded host–guest systems in two organic solvents and two ionic liquids yield smaller yet comparable Ka values in ionic liquids than in organic solvents. We also detect the association event using force spectroscopy, which confirms that the binding is not solely due to (de)solvation processes. Our results indicate that classic H-bonded host–guest supramolecular chemistry takes place in ILs. This implies that strong H-bonds are only moderately affected by surroundings composed entirely of charges, which can be interpreted as an indication that the balance of Coulombic to covalent forces in strong H-bonds is not tipped towards the former.
Chloroplast development and genomes uncoupled signaling are independent of the RNA-directed DNA methylation pathway
Authors: Wang Liangsheng , Leister Dario , Kleine Tatjana 
Published: September 2020

AbstractThe Arabidopsis genome is methylated in CG and non-CG (CHG, and CHH in which H stands for A, T, or C) sequence contexts. DNA methylation has been suggested to be critical for seed development, and CHH methylation patterns change during stratification and germination. In plants, CHH methylation occurs mainly through the RNA-directed DNA methylation (RdDM) pathway. To test for an involvement of the RdDM pathway in chloroplast development, we analyzed seedling greening and the maximum quantum yield of photosystem II (Fv/Fm) in Arabidopsis thaliana seedlings perturbed in components of that pathway. Neither seedling greening nor Fv/Fm in seedlings and adult plants were affected in this comprehensive set of mutants, indicating that alterations in the RdDM pathway do not affect chloroplast development. Application of inhibitors like lincomycin or norflurazon inhibits greening of seedlings and represses the expression of photosynthesis-related genes including LIGHT HARVESTING CHLOROPHYLL A/B BINDING PROTEIN1.2 (LHCB1.2) in the nucleus. Our results indicate that the LHCB1.2 promoter is poorly methylated under both control conditions and after inhibitor treatment. Therefore no correlation between LHCB1.2 mRNA transcription and methylation changes of the LHCB1.2 promoter could be established. Moreover, we conclude that perturbations in the RdDM pathway do not interfere with gun signaling.
Dynamic and subtype-specific interactions between tumour burden and prognosis in breast cancer
Authors: Lee S. B. , Kim H.-K. , Choi Y. , Ju Y. W. , Lee H.-B. , Han W. , Noh D.-Y. , Son B. H. , Ahn S. H. , Kim K. S. , Nam S. J. , Kim E.‑K. , Park H. Y. , Park W.-C. , Lee J. W. , Moon H.-G. 
Published: September 2020

AbstractWe investigated the relationship between the prognostic importance of anatomic tumour burden and subtypes of breast cancer using data from the Korean Breast Cancer Registry Database. In HR+/HER2+ and HR−/HER2−tumours, an increase in T stage profoundly increased the hazard of death, while the presence of lymph node metastasis was more important in HR+/HER2+ and HR−/HER2+ tumours among 131,178 patients with stage I–III breast cancer. The patterns of increasing mortality risk and tumour growth (per centimetre) and metastatic nodes (per node) were examined in 67,038 patients with a tumour diameter ≤ 7 cm and < 8 metastatic nodes. HR+/HER2− and HR−/HER2− tumours showed a persistent increase in mortality risk with an increase in tumour diameter, while the effect was modest in HER2+ tumours. Conversely, an increased number of metastatic nodes was accompanied by a persistently increased risk in HR−/HER2+ tumours, while the effect was minimal for HR−/HER2− tumours with > 3 or 4 nodes. The interactions between the prognostic significance of anatomic tumour burden and subtypes were significant. The prognostic relevance of the anatomic tumour burden was non-linear and highly dependent on the subtypes of breast cancer.
Binary symbolic dynamics analysis to detect stress-associated changes of nonstationary heart rate variability
Authors: Spellenberg Conrad , Heusser Peter , Büssing Arndt , Savelsbergh Andreas , Cysarz Dirk 
Published: September 2020

AbstractPsychological stress may have harmful physiological effects and result in deteriorating health. Acute psychological stress acts also on cardiac autonomic regulation and may lead to nonstationarities in the interbeat interval series. We address the requirement of stationary RR interval series to calculate frequency domain parameters of heart rate variability (HRV) and use binary symbolic dynamics derived from RR interval differences to overcome this obstacle. 24 healthy subjects (12 female, 20–35 years) completed the following procedure: waiting period, Trier Social Stress Test to induce acute psychological stress, recovery period. An electrocardiogram was recorded throughout the procedure and HRV parameters were calculated for nine 5-min periods. Nonstationarities in RR interval series were present in all periods. During acute stress the average RR interval and SDNN decreased compared to rest before and after the stress test. Neither low frequency oscillations (LF), high frequency oscillations (HF) nor LF/HF could unambiguously reflect changes during acute stress in comparison to rest. Pattern categories derived from binary symbolic dynamics clearly identified acute stress and accompanying alterations of cardiac autonomic regulation. Methods based on RR interval differences like binary symbolic dynamics should be preferred to overcome issues related to nonstationarities.
Fueling of a marine-terrestrial ecosystem by a major seabird colony
Authors: Hentati-Sundberg J. , Raymond C. , Sköld M. , Svensson O. , Gustafsson B. , Bonaglia S. 
Published: September 2020

AbstractSeabirds redistribute nutrients between different ecosystem compartments and over vast geographical areas. This nutrient transfer may impact both local ecosystems on seabird breeding islands and regional biogeochemical cycling, but these processes are seldom considered in local conservation plans or biogeochemical models. The island of Stora Karlsö in the Baltic Sea hosts the largest concentration of piscivorous seabirds in the region, and also hosts a large colony of insectivorous House martins Delichon urbicum adjacent to the breeding seabirds. We show that a previously reported unusually high insectivore abundance was explained by large amounts of chironomids—highly enriched in δ15N—that feed on seabird residues as larvae along rocky shores to eventually emerge as flying adults. Benthic ammonium and phosphate fluxes were up to 163% and 153% higher close to the colony (1,300 m distance) than further away (2,700 m) and the estimated nutrient release from the seabirds at were in the same order of magnitude as the loads from the largest waste-water treatment plants in the region. The trophic cascade impacting insectivorous passerines and the substantial redistribution of nutrients suggest that seabird nutrient transfer should be increasingly considered in local conservation plans and regional nutrient cycling models.
The distinctive geographic patterns of common pigmentation variants at the OCA2 gene
Authors: Kidd Kenneth K. , Pakstis Andrew J. , Donnelly Michael P. , Bulbul Ozlem , Cherni Lotfi , Gurkan Cemal , Kang Longli , Li Hui , Yun Libing , Paschou Peristera , Meiklejohn Kelly A. , Haigh Eva , Speed William C. 
Published: September 2020

AbstractOculocutaneous Albinism type 2 (OCA2) is a gene of great interest because of genetic variation affecting normal pigmentation variation in humans. The diverse geographic patterns for variant frequencies at OCA2 have been evident but have not been systematically investigated, especially outside of Europe. Here we examine population genetic variation in and near the OCA2 gene from a worldwide perspective. The very different patterns of genetic variation found across world regions suggest strong selection effects may have been at work over time. For example, analyses involving the variants that affect pigmentation of the iris argue that the derived allele of the rs1800407 single nucleotide polymorphism, which produces a hypomorphic protein, may have contributed to the previously demonstrated positive selection in Europe for the enhancer variant responsible for light eye color. More study is needed on the relationships of the genetic variation at OCA2 to variation in pigmentation in areas beyond Europe.
Detecting differential ground displacements of civil structures in fast-subsiding metropolises with interferometric SAR and band-pass filtering
Authors: Solano-Rojas Darío , Wdowinski Shimon , Cabral-Cano Enrique , Osmanoğlu Batuhan 
Published: September 2020

AbstractGround displacements due to changes in soil conditions represent a threat to the stability of civil structures in many urban areas, worldwide. In fast-subsiding areas, regional subsidence (wavelength ~ 1,000’s m) can be dominantly high and, consequently, mask other signals at local scales (wavelength ~ 10–100’s m). Still, engineering and construction applications require a comprehensive knowledge of local-scale signals, which can threaten the stability of buildings and infrastructure. Here we present a new technique based on band-pass filters for uncovering local-scale signals hidden by regional subsidence as detected by interferometric SAR measurements. We apply our technique to a velocity field calculated from 21 high-resolution COSMO-SkyMed scenes acquired over Mexico City and obtain components of long (> 478 m), intermediate (42–478 m) and short (< 42 m) spatial wavelengths. Our results reveal that long-wavelength velocities exceed − 400 mm/year, whereas intermediate- and short-wavelength velocities are in the order of ± 15 mm/year. We show that intermediate-wavelength velocities are useful for retrieving signals such as uplift along elevated viaducts of Metro lines 4 and B, as well as differential displacements in Pantitlán station’s pedestrian overpass system and across sharp geotechnical boundaries in the piedmont of Sierra de Santa Catarina—where surface faulting occurs.
Early-stage knee OA induced by MIA and MMT compared in the murine model via histological and topographical approaches
Authors: Aüllo-Rasser Gaetan , Dousset Erick , Roffino Sandrine , Zahouani Hassan , Lecurieux-Clerville Roger , Argenson Jean-Noël , Chabrand Patrick 
Published: September 2020

AbstractOsteoarthritis (OA) is a common degenerative disease whose early management includes promising mechanical treatments. New treatments are initially validated using an animal model in which OA is induced. The MMT (mechanical induction) and MIA (chemical induction) models of OA induction are widespread, but their use to generate early OA is poorly documented. We analyzed and compared early-stage knee OA-induction via these two methods in 16 rats divided into two groups. After 4 weeks of induction, the knees were sampled and studied using both histology (Toluidine Blue and Sirius Red) and surface topology, an innovative technique for characterizing osteoarthritic cartilage. The Mankin-modified score confirms that the two OA-induction models evolved at the same speed. At this early stage, the two models can be differentiated morphologically, although no significant differences were revealed by either cellularity or birefringence analysis. However, the topological analysis generated two forms of quantitative data, the deformation ratio and the cohesion index, that differentiated between the two groups. Thus, the early-stage OA induced by these two models is revealed to differ. The patterns of cartilage damage induced point to MMT as the better choice to assess mechanical approaches to clinical OA treatment.
Divalent cation-induced conformational changes of influenza virus hemagglutinin
Authors: Seok Jong Hyeon , Kim Hyojin , Lee Dan Bi , An Jeong Suk , Kim Eun Jeong , Lee Ji-Hye , Chung Mi Sook , Kim Kyung Hyun 
Published: September 2020

AbstractDivalent cations Cu2+ and Zn2+ can prevent the viral growth in mammalian cells during influenza infection, and viral titers decrease significantly on a copper surface. The underlying mechanisms include DNA damage by radicals, modulation of viral protease, M1 or neuraminidase, and morphological changes in viral particles. However, the molecular mechanisms underlying divalent cation-mediated antiviral activities are unclear. An unexpected observation of this study was that a Zn2+ ion is bound by Glu68 and His137 residues at the head regions of two neighboring trimers in the crystal structure of hemagglutinin (HA) derived from A/Thailand/CU44/2006. The binding of Zn2+ at high concentrations induced multimerization of HA and decreased its acid stability. The acid-induced conformational change of HA occurred even at neutral pH in the presence of Zn2+. The fusion of viral and host endosomal membranes requires substantial conformational changes in HA upon exposure to acidic pH. Therefore, our results suggest that binding of Zn2+ may facilitate the conformational changes of HA, analogous to that induced by acidic pH.
Neural sources of letter and Vernier acuity
Authors: Barzegaran Elham , Norcia Anthony M. 
Published: September 2020

AbstractVisual acuity can be measured in many different ways, including with letters and Vernier offsets. Prior psychophysical work has suggested that the two acuities are strongly linked given that they both depend strongly on retinal eccentricity and both are similarly affected in amblyopia. Here we used high-density EEG recordings to ask whether the underlying neural sources are common as suggested by the psychophysics or distinct. To measure visual acuity for letters, we recorded evoked potentials to 3 Hz alternations between intact and scrambled text comprised of letters of varying size. To measure visual acuity for Vernier offsets, we recorded evoked potentials to 3 Hz alternations between bar gratings with and without a set of Vernier offsets. Both alternation types elicited robust activity at the 3 Hz stimulus frequency that scaled in amplitude with both letter and offset size, starting near threshold. Letter and Vernier offset responses differed in both their scalp topography and temporal dynamics. The earliest evoked responses to letters occurred on lateral occipital visual areas, predominantly over the left hemisphere. Later responses were measured at electrodes over early visual cortex, suggesting that letter structure is first extracted in second-tier extra-striate areas and that responses over early visual areas are due to feedback. Responses to Vernier offsets, by contrast, occurred first at medial occipital electrodes, with responses at later time-points being more broadly distributed—consistent with feedforward pathway mediation. The previously observed commonalities between letter and Vernier acuity may be due to common bottlenecks in early visual cortex but not because the two tasks are subserved by a common network of visual areas.