Lightweight magnesium alloys are attractive as structural materials for improving energy efficiency in applications such as weight reduction of transportation vehicles. One major obstacle for ...widespread applications is the limited ductility of magnesium, which has been attributed to Formula: see text dislocations failing to accommodate plastic strain. We demonstrate, using in situ transmission electron microscope mechanical testing, that Formula: see text dislocations of various characters can accommodate considerable plasticity through gliding on pyramidal planes. We found that submicrometer-size magnesium samples exhibit high plasticity that is far greater than for their bulk counterparts. Small crystal size usually brings high stress, which in turn activates more Formula: see text dislocations in magnesium to accommodate plasticity, leading to both high strength and good plasticity.
•MOF nanoparticles are assembled on the bacterial cellulose by weak interaction.•MOF aerogels with hierarchical structures are flexible and lightweight.•BC@ZIF-8 demonstrates an excellent adsorption ...performance of heavy metal ions.•BC@UiO-66@PDA interlayer can improve the performance of Li-S batteries.
Flexible metal-organic framework (MOF) aerogels with practical macroscopic shapeability and hierarchical porosity were prepared through in-site growth of MOF nanoparticles, i.e. zeolitic imidazolate framework-8 (ZIF-8) and University of Oslo-66 (UiO-66), on bacteria cellulose (BC). The yielded composite aerogels inherit high porosities from feedstock MOFs and mechanical flexibility from BC template. BC template offers high porosity, mechanical flexibility to the composite aerogels, which significantly suppresses the aggregation of individual MOF nanoparticles. Owing to the structural characteristics of MOF and BC, BC@ZIF-8 composite aerogel sponges exhibit a low density below 0.03 g cm−3, hierarchical porosity, large surface area, high mass transfer efficiency and superior adsorption performance of heavy metal ions. After 24 h adsorption in simulated industrial waterwastes, removal efficiency of the composite aerogels reaches up to 81% with respect to Pb2+ ion pollutants, which is 1.2 times higher than that of original ZIF-8 nanoparticle counterparts. BC@UiO-66 composite aerogel film, as a flexible lithium-sulfur battery interlayer, demonstrates a high reversible capacity of 631 mAh g−1 at 0.5C over 100 cycles, which is attributed to its selectivity for Li+ ions and efficient inhibition to the soluble polysulfide ions. In addition, the presence of polydopamine (PDA) coating on BC@UiO-66 nanofibers in BC@UiO-66@PDA composite aerogel films increases reversible capacity up to 739 mAh g−1 at 0.5 C over 100 cycles. This work provides a feasible solution to process MOF powders into a flexible and tailorable form, and holds a new promise to rational design and manufacturing of MOF monoliths with a great structural diversity as advanced multifunctional materials.
A key issue for perovskite solar cells is the stability of perovskite materials due to moisture effects under ambient conditions, although their efficiency is improved constantly. Herein, an improved ...CH3NH3PbI3−xClx perovskite quality is demonstrated with good crystallization and stability by using water as an additive during crystal perovskite growth. Incorporating suitable water additives in N,N‐dimethylformamide (DMF) leads to controllable growth of perovskites due to the lower boiling point and the higher vapor pressure of water compared with DMF. In addition, CH3NH3PbI3−xClx · nH2O hydrated perovskites, which can be resistant to the corrosion by water molecules to some extent, are assumed to be generated during the annealing process. Accordingly, water additive based perovskite solar cells present a high power conversion efficiency of 16.06% and improved cell stability under ambient conditions compared with the references. The findings in this work provide a route to control the growth of crystal perovskites and a clue to improve the stability of organic–inorganic halide perovskites.
Water additive is incorporated into the perovskite precursor solution to control the oriented growth of crystal perovskites and improve the stability of perovskite solar cells. As a result, a power conversion efficiency of 16.06% and an improved cell stability under ambient conditions are achieved.
•Taxifolin improved diastolic dysfunction in streptozotocin-induced diabetic mice.•Taxifolin inhibited oxidative stress by enhancing antioxidative enzymes’ activities.•Taxifolin inhibited NADPH ...oxidase activities and reduced ROS level.•JAK/STAT pathway was involved in the protective effects of taxifolin.
Diabetic cardiomyopathy has been increasingly recognized as an important cause of heart failure in diabetic patients. Excessive oxidative stress has been suggested to play a critical role in the development of diabetic cardiomyopathy. The objective of this study was to investigate the potential protective effects and mechanisms of taxifolin on cardiac function of streptozotocin-induced diabetic mice and on hyperglycemia-induced apoptosis of H9c2 cardiac myoblasts. In vivo study revealed that taxifolin improved diastolic dysfunction, ameliorated myocardium structure abnormality, inhibited myocyte apoptosis and enhanced endogenous antioxidant enzymes activities. Interestingly, taxifolin reduced angiotensin II level in myocardium, inhibited NADPH oxidase activity, and increased JAK/STAT3 activation. In vitro investigation demonstrated that taxifolin inhibited 33mM glucoseinduced H9c2 cells apoptosis by decreasing intracellular ROS level. It also inhibited caspase-3 and caspase-9 activation, restored mitochondrial membrane potential, and regulated the expression of proteins related to the intrinsic pathway of apoptosis, thus inhibiting the release of cytochrome c from mitochondria into the cytoplasm. In conclusion, taxifolin exerted cardioprotective effects against diabetic cardiomyopathy by inhibiting oxidative stress and cardiac myocyte apoptosis and might be a potential agent in the treatment of diabetic cardiomyopathy.
HOTAIR is an important carcinogenic lncRNA and involves in tumorigenesis, and invasion. MiR‐34a‐5p functions as a tumour suppressor. However, the underlying mechanism of HOTAIR regulation especially ...in association with miR‐34a‐5p in non‐small‐cell lung cancer (NSCLC) has not been explored. Herein, we performed series of in vitro experiments, including viability, migration, invasion, apoptosis and in vivo xenograft model, and identified that HOTAIR was remarkably elevated in NSCLC cells. Enforced HOTAIR expression promoted migration and invasion, while depleted HOTAIR diminished the ability of migration and invasion of NSCLC cells. We also observed that miR‐34a‐5p was dramatically inhibited in NSCLC cells and the binding correlation between HOTAIR and miR‐34a‐5p was confirmed by dual‐luciferase reporter and RNA immunoprecipitation assays. We also showed that induction of miR‐34a‐5p and reduction of HOTAIR, and the interaction between miR‐34a‐5p and HOTAIR resulted in the suppression of epithelial‐mesenchymal transition (EMT) as illustrated by induction of key epithelial markers E‐cadherin expression, reduction of vimentin and EMT‐inducing transcription factor snail. Excessive expression of snail resisted miR‐34a‐5p‐inhibited cell growth. Snail binds to E‐cadherin promoter and regulates E‐cadherin expression. There was a synergy in combination of berberine and gefinitib in this process. Similar findings were also observed in a tumour xenograft model. Collectively, this is the first report demonstrating reciprocal interaction of miR‐34a‐5p‐ and HOTAIR‐mediated regulation of snail resulting in inhibition of EMT process by the combination of berberine and gefitinib suggesting that regulation of miR‐34a‐5p‐ and HOTAIR‐mediated inhibition of EMT may provide novel treatment paradigms for lung cancer.
Photocatalytic catalysis is widely used for pollutant degradation. Since some pollutants with oxidative nature are readily reduced rather than oxidized and reductive reaction caused by photogenerated ...electrons is limited in the presence of oxygen, photocatalytic reduction process is more applicable for the degradation of pollutants with oxidative nature than oxidation. In this work, a novel bio-photoelectric reductive degradation system (BPRDS), composed of an electrochemically active bacterium Shewanella oneidensis MR-1 and a visible-light photocatalyst Ag3PO4, was established under anaerobic conditions and its photodegradation performance was evaluated through degrading rhodamine B (RhB), a typical organic pollutant. The as-synthesized Ag3PO4 nanoparticles exhibited absorption in the entire visible spectral range of 400–800 nm. RhB could be degraded in BPRDS with visible light irradiation under anaerobic conditions, but not be decomposed in the absence of Shewanella cells. Block of Mtr respiratory pathway, a transmembrane electron transport chain, resulted in a reduction in degradation rate of RHB in BPRDS. Dose of riboflavin also substantially decreased the RhB degradation. These results suggest that the electrons released by Shewanella were involved in the RhB photodegradation, which was achieved via a stepwise N-deethylation process. In BPRDS, RhB was degraded by photoreduction, rather than photooxidation. This work is useful to develop integrated physico-chemical-microbial systems for pollutant degradation, facilitate better understanding about the biophotoelectric reductive degradation mechanisms and beneficial to their applications for environmental remediation.
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•A bio-photoelectric reductive degradation system (BPRDS) was constructed.•RhB was anaerobically degraded by BPRDS under visible light excitation.•Electrons released by Shewanella were essential for the BPRDS operation.•Shewanella acted as the hole scavenger in the photoexcitation of Ag3PO4.
P2X receptors are non-selective cation channels gated by extracellular ATP, and the P2X7 receptor subtype plays a crucial role in the immune and nervous systems. Altered expression and dysfunctions ...of P2X7 receptors caused by genetic deletions, mutations, and polymorphic variations have been linked to various diseases, such as rheumatoid arthritis and hypertension. Despite the availability of crystal structures of P2X receptors, the mechanism of competitive antagonist action for P2X receptors remains controversial. Here, we determine the crystal structure of the chicken P2X7 receptor in complex with the competitive P2X antagonist, TNP-ATP. The structure reveals an expanded, incompletely activated conformation of the channel, and identified the unique recognition manner of TNP-ATP, which is distinct from that observed in the previously determined human P2X3 receptor structure. A structure-based computational analysis furnishes mechanistic insights into the TNP-ATP-dependent inhibition. Our work provides structural insights into the functional mechanism of the P2X competitive antagonist.P2X receptors are nonselective cation channels that are gated by extracellular ATP. Here the authors present the crystal structure of chicken P2X7 with its bound competitive antagonist TNP-ATP and give mechanistic insights into TNP-ATP dependent inhibition through further computational analysis and electrophysiology measurements.
The Corona Virus Disease 2019 (COVID‐19) pandemic has attracted increasing worldwide attention. While metabolic‐associated fatty liver disease (MAFLD) affects a quarter of world population, its ...impact on COVID‐19 severity has not been characterized. We identified 55 MAFLD patients with COVID‐19, who were 1:1 matched by age, sex and obesity status to non‐aged severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2)‐infected patients without MAFLD. Our results demonstrate that in patients aged less than 60 years with COVID‐19, MAFLD is associated with an approximately fourfold increase (adjusted odds ratio 4.07, 95% confidence interval 1.20‐13.79, P = .02) in the probability for severe disease, after adjusting for confounders. Healthcare professionals caring for patients with COVID‐19 need to be aware that there is a positive association between MAFLD and severe illness with COVID‐19.
Isoniazid(INH) is highly effective for the management of tuberculosis.However,it can cause liver injury and even liver failure.INH metabolism has been thought to be associated with INH-induced liver ...injury.This review summarized the metabolic pathways of INH and discussed their associations with INH-induced liver injury.
The earthworm is particularly fascinating to biologists because of its strong regenerative capacity. However, many aspects of its regeneration in nature remain elusive. Here we report ...chromosome-level genome, large-scale transcriptome and single-cell RNA-sequencing data during earthworm (Eisenia andrei) regeneration. We observe expansion of LINE2 transposable elements and gene families functionally related to regeneration (for example, EGFR, epidermal growth factor receptor) particularly for genes exhibiting differential expression during earthworm regeneration. Temporal gene expression trajectories identify transcriptional regulatory factors that are potentially crucial for initiating cell proliferation and differentiation during regeneration. Furthermore, early growth response genes related to regeneration are transcriptionally activated in both the earthworm and planarian. Meanwhile, single-cell RNA-sequencing provides insight into the regenerative process at a cellular level and finds that the largest proportion of cells present during regeneration are stem cells.
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