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Hierarchical porous carbon with highly active sites has emerged as an ideal support for high‐performance oxygen reduction reaction (ORR) electrocatalysts. By tuning the geometric size and coordination environment of transition metals on hierarchical porous carbon to optimize the catalytic performance for ORR, cobalt (Co) single atoms and Co nanoclusters were synthesized respectively on N‐doping and vacancy‐defective hierarchical porous carbon. Benefited from the high surface area and enhanced mass transfer, cobalt nanoclusters on nitrogen doped hierarchical porous carbon shows a high four‐electron selectivity for ORR. It presents a half wave potential of 0.854 V vs. RHE, which is comparable to that of commercial Pt/C catalysts (0.852 V vs. RHE). Meanwhile, the single‐atomic cobalt coordinated with vacancy‐defective carbon favors the two‐electron reduction of O2 to hydrogen peroxide (H2O2). It exhibits an apparent promotion on selectivity of two‐electron route with a high H2O2 selectivity of around 90 %. This work demonstrates that hierarchical porous carbons could be effectively tuned for applications that favors either four‐electron or two‐electron ORR pathway. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs), as a sustainable and promising technology to solve both environmental pollution and energy shortage, have captured tremendous attention. The conversion efficiency of chemical energy contained in organic waste or wastewater to electricity via microbial metabolism strongly depends on the performance of each functional unit, including the anode, cathode and separator/membrane used in MFCs. Therefore, significant attention has been paid toward developing advanced functional materials to enhance the performance of each unit or provide new featured functions. This review paper provides a comprehensive review on recent achievements and advances in the modification and development of functional materials for MFC systems, including 1) the development of functional anode materials for enhanced microbial compatibilities as well as electron transfer capabilities, 2) the development of cost‐effective separators/membranes such as ion exchange membrane, porous membrane, polymer electrolyte membrane and composite membrane, and 3) the development of functional cathode catalysts to decrease the over‐potential and enhance the electrocatalytic efficiency for oxygen reduction reaction in order to substitute the common costly Pt catalyst. The challenges and outlooks of functional materials for MFC applications are also discussed. [ABSTRACT FROM AUTHOR]

Switching the formic acid oxidation reaction (FAOR) pathway from CO intermediate to direct CO2 formation is essential for noble‐metal electrocatalysts, but rare investigations on Ir‐based materials. Herein, the atomic configurations of Ir are controlled to enhance the FAOR performance via Ir3V intermetallics (O‐Ir3V). As the ordering degree of O‐Ir3V increases, the Ir ensemble size decreases to trimer and dimer, leading to a 7.3 times promotion in mass normalized activity relative to Ir. Supported by electrochemical in situ attenuated total reflection infrared spectroscopy results, it shows that FAOR occurs via linear CO mediated pathway on Ir, but it is totally switched to a direct pathway on highly ordered O‐Ir3V. The preserved ordered structure and V oxides on the surface during the durability test contribute to the enhanced stability. This study provides an idea to switch the FAOR pathway through tuning the Ir atom configuration by constructing ordered intermetallics. [ABSTRACT FROM AUTHOR]

Background and Purpose: Macrophages regulate iron homeostasis in the liver and play important role in hepatic ischaemia/reperfusion (I/R) injury. This study investigates the role of macrophages in iron overload‐related hepatocyte damage during liver I/R. Experimental Approach Liver biopsies from patients undergoing partial hepatectomy with or without hepatic portal occlusion were recruited and markers of hepatocyte cell death and macrophage extracellular traps (METs) were detected. A murine hepatic I/R model was also established in high‐iron diet‐fed mice. Ferrostatin‐1 and deferoxamine were administered to investigate the role of ferroptosis in hepatic I/R injury. The macrophage inhibitor liposome‐encapsulated clodronate was used to investigate the interaction between macrophages and ferroptosis. AML12 hepatocytes and RAW264.7 macrophages were co‐cultured in vitro. An inhibitor of macrophage extracellular traps was used to evaluate the role and mechanism of these traps and ferroptosis in hepatic I/R injury. Key Results: Hepatocyte macrophage extracellular trap formation and ferroptosis were greater in patients who underwent hepatectomy with hepatic portal occlusion and in mice subjected to hepatic I/R. Macrophage extracellular traps increased when macrophages were subjected to hypoxia/reoxygenation and when they were co‐cultured with hepatocytes. Ferroptosis increased and post‐hypoxic hepatocyte survival decreased, which were reversed by inhibition of macrophage extracellular traps. Ferroptosis inhibition attenuated post‐ischaemic liver damage. Moreover, iron overload induced hepatic ferroptosis and exacerbated post‐ischaemic liver damage, which were reversed by the iron chelator. Conclusion and Implications: Macrophage extracellular traps are in volved in regulating ferroptosis highlighting the therapeutic potential of macrophage extracellular traps and ferroptosis inhibition in reducing liver I/R injury. [ABSTRACT FROM AUTHOR]

Aims: Schistosomiasis is a parasitic disease with a chronic debilitating character caused by parasitic flatworms of the genus Schistosoma. The main disease‐causing species of Schistosoma in China is S. japonicum. M fortis has been proved to be a nonpermissive host of S. japonicum. Mf‐HSP90α (Microtus fortis heat shock protein 90alpha), the homologue of HSP90α, display anti‐schistosome effect in vitro and in vivo. In the current study, in order to investigate the mechanism of anti‐schistosome effect of Mf‐HSP90α, we conducted RNA‐Seq to obtain the transcriptome profile of M. fortis liver infected with S. japonicum at different time points. Methods and Results: By mapping the differential expressed genes (DEGs) to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), we found that the JAK2/STAT1 pathway was highly enriched with an elevated level of IL‐10 and HSP90α. We then checked the IL‐10‐JAK2/STAT1‐HSP90α pathway, and found that this pathway was activated in the infected mice with S. japonicum. The expression of the molecules in this pathway was elevated on the 10th day after infection and gradually decreased on the 20th day. Conclusions: The IL‐10‐JAK2/STAT1‐HSP90α axis was associated with the anti‐schistosome effect of Mf‐HSP90α, and targeting IL‐10‐JAK2/STAT1‐HSP90α axis might be a novel therapeutic strategy for developing resistance to S. japonicum infection. [ABSTRACT FROM AUTHOR]

U2AF1 (U2AF35) is the small subunit of the U2 auxiliary factor (U2AF) that constitutes the U2 snRNP (small nuclear ribonucleoproteins) of the spliceosome. Here, we examined the function of U2AF1 in human erythropoiesis. First, we examined the expression of U2AF1 during in vitro human erythropoiesis and showed that U2AF1 was highly expressed in the erythroid progenitor burst‐forming‐unit erythroid (BFU‐E) cell stage. A colony assay revealed that U2AF1 knockdown cells failed to form BFU‐E and colony‐forming‐unit erythroid (CFU‐E) colonies. Our results further showed that knockdown of U2AF1 significantly inhibited cell growth and induced apoptosis in erythropoiesis. Additionally, knockdown of U2AF1 also delayed terminal erythroid differentiation. To explore the molecular basis of the impaired function of erythroid development, RNA‐seq was performed and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis results showed that several biological pathways, including the p53 signalling pathway, MAPK signalling pathway and haematopoietic cell lineage, were involved, with the p53 signalling pathway showing the greatest involvement. Western blot analysis revealed an increase in the protein levels of downstream targets of p53 following U2AF1 knockdown. The data further showed that depletion of U2AF1 altered alternatively spliced apoptosis‐associated gene transcripts in CFU‐E cells. Our findings elucidate the role of U2AF1 in human erythropoiesis and reveal the underlying mechanisms. [ABSTRACT FROM AUTHOR]

The daphniphyllum alkaloids are a structurally fascinating and remarkably diverse family of natural products. General strategies for the chemical synthesis of their challenging architectures are highly desirable for efficiently accessing these intriguing alkaloids and addressing their pharmaceutical potential. Herein, a concise strategy designed to provide general and diversifiable access to various daphniphyllum alkaloids is described and utilized in the asymmetric synthesis of (−)‐himalensine A, which was accomplished in 14 steps. Key features of this strategy include a Cu‐catalyzed nitrile hydration, a Heck reaction to construct the challenging 2‐azabicyclo[3.3.1]nonane motif, a Meinwald rearrangement reaction, six, pot‐economic reactions, and the minimal use of protecting groups, which significantly improved the overall synthetic efficiency. [ABSTRACT FROM AUTHOR]

Aims/Introduction: Dipeptidyl peptidase‐4 inhibitor has been proven to improve glycemic control and β‐cell function in latent autoimmune diabetes in adults (LADA). The potential immune modulation mechanism is still unknown. Thus, we tested T‐lymphocyte subsets and expression of relevant transcription factors in LADA patients with sitagliptin intervention for up to 1‐year. Materials and Methods: A total of 40 LADA patients were randomly assigned to sitagliptin and/or insulin treatment (SITA group; n = 20) or insulin alone treatment (CONT group; n = 20). Peripheral blood mononuclear cells were isolated at baseline, 6 months and 12 months. The percentage of T‐lymphocyte subsets (T helper 1, T helper 2, T helper 17 and regulatory T cells) tested by flow cytometry, and the messenger ribonucleic acid expression (T box expressed in T cells [T‐BET], GATA binding protein 3 [GATA3], forkhead box protein 3 [FOXP3] and related orphan receptor C [RORC]) tested by real‐time polymerase chain reaction were determined at baseline, 6 months and 12 months. Results: The percentage of regulatory T cells in the SITA group was significantly lower than that of the CONT group at baseline. The percentage of T helper 2 cells was higher than that of the CONT group at 6 months and 12 months. At 12 months, the percentage of T helper 17 cells was lower in the SITA group than that of the CONT group. After a 1‐year visit, the messenger ribonucleic acid expression levels of T‐BET expressed in T cells and RORC in the SITA group were significantly lower than at baseline. Whereas that of RORC in the CONT group were significantly lower than that at baseline. Conclusions: The data confirmed that sitagliptin altered the phenotype of T cells and downregulated the expression of T‐BET and RORC in LADA patients, and ameliorated glycemic control in LADA patients. Th2 was higher and Th17 was lower in SITA group than that in CONT group at 12M. Meanwhile, the mRNA expression levels of both T‐BET and RORC in SITA group were significantly lower than its baseline. We first implicated that sitagliptin, a DPP4 inhibitor, could alter the frequency of CD4+ T cell subsets on both cellular and mRNA level in LADA patients. [ABSTRACT FROM AUTHOR]

BACKGROUND The lead oxide product recovered from spent lead‐acid battery paste via the hydrometallurgical route usually contains many impurity elements, i.e. Ba and Fe. In this paper, a facile lead acetate conversion process was proposed for synthesis of high‐purity alpha‐lead oxide (α‐PbO) derived from spent lead‐acid batteries. RESULTS: The desulfurized lead paste was leached with acetic acid and hydrogen peroxide to prepare lead acetate solution, which was then reacted with sodium hydroxide solution to synthesize high‐purity α‐PbO. The doses of acetic acid and hydrogen peroxide were the two key parameters for the removals of the impurities, due to their dominant effects on the pH and redox potential of the leaching step. Under the optimized conditions (the molar ratios of CH3COOH/Pb of 2.00, H2O2/PbO2 of 3.5, and NaOH/Pb of 2.5), the high‐purity α‐PbO product with impurities of 20.5 mg kg−1 Fe and 1.5 mg kg−1 Ba was prepared, which were the lowest impurities content in lead product recovered via a hydrometallurgical route compared with previous literature. The total removal efficiencies of impurities Ba and Fe reached 99.9 wt% and 99.0 wt%, respectively. The total recovery efficiency of Pb from the spent lead paste was 92.6 wt%. CONCLUSION: The proposed acetic acid leaching process was proved to be an effective strategy to remove the impurities via a hydrometallurgical route. The recovered high‐purity α‐PbO could be used as the positive active materials for lead‐acid battery. This study could provide insights into the impurities removal in the hydrometallurgical recovery of spent lead paste. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Lead citrate is an attractive precursor for the preparation of ultrafine leady oxide from the paste in spent lead-acid batteries through a novel hydrometallurgical process, since the recovered lead oxide could be recycled for the production of new lead acid batteries. RESULTS: Two differentmetal organic complexes were synthesized fromlead sulfate fromthe paste of spent lead-acid batteries in a leaching solution at two different initial pH values. Single crystals of the two precursors were obtained by conditioning and filtering from the leached solutions, and used for single crystal XRD analysis. At an initial pH of 3.5, the chemical formula of Precursor-I is deduced to be Pb(C6H6O7)·H2O while at an initial pH of 5.2, the chemical formula of Precursor-II is Pb3(C6H5O7)2·3H2O. CONCLUSIONS: Both Precursor-I and Precursor-II crystallize in the triclinic crystal system, with space group P-1. This structural study on precursors sheds light on themechanism of a paste-to-paste recovery route for the recovery of spent lead paste. [ABSTRACT FROM AUTHOR]

The electrodeposition of Pt-PrO2− x nanostructures on boron-doped diamond electrodes was explored by decorating platinum nanoparticles with praseodymium oxide, for application as an electrocatalyst in the electrooxidation of methanol in direct methanol fuel cells. A high loading of platinum with good stability was deposited by adopting a two-stage protocol, which involved a stepped potential route and a chronoamperometric approach. Praseodymium oxide was then coated on the platinum particles from solutions containing praseodymium nitrate and hydrogen peroxide. The porous microstructure of the resulting catalyst was characterized by X-ray photoelectron spectroscopy and scanning electron microscope, along with electrochemical measurement. The addition of praseodymium oxide to the Pt resulted in a higher catalytic activity profile for methanol oxidation along with an improved resistance to poisoning effects caused by incompletely oxidized carbonaceous species. [ABSTRACT FROM AUTHOR]

Both contaminated natural soil and simulated contaminated kaolinite have been used for electrokinetic remediation (EKR) of toxic metal(s). The objectives of this study are to make a comparison on the EKR performance between lead‐contaminated natural soil (NatSoil) and simulated lead‐contaminated kaolinite (KlnSoil), and to explore the intrinsic mechanism for the discrepancy between these two cases. Results show that the EKR process on NatSoil failed to achieve effective Pb enrichment in any soil section (in total four) with either KNO3 or EDTA‐2Na as the catholyte. However, enrichment ratios (C/C0) of 2.11 and 4.45 are achieved on KlnSoil with the above two electrolytes, respectively. The speciation of Pb in different soil samples, 55.81% of Pb in reducible fraction in NatSoil and 85.06% of Pb in exchangeable and soluble fraction in KlnSoil, are attributed to the significant differences of remediation. The mineral components, cation exchange capacity, acid/base buffering capacity are more complex than that of KlnSoil, hindering the desorption and migration of Pb2+. Increasing the voltage from 2 to 4 V cm−1, pre‐saturating the soil sample with EDTA‐2Na instead of deionized water and prolonging the treatment time from 240 to 480 h successfully enhance the enrichment ratio of Pb at the third soil section to 2.44, 1.70, and 1.69, respectively. The energy consumptions of the remediation processes are also evaluated. Overall, pre‐saturating the soil samples with EDTA‐2Na is the optimal strategy for NatSoil considering the balance between the remediation efficiency and energy consumption. Superior electrokinetic remediation (EKR) effect of Pb is achieved on contaminated kaolinite compared to natural soils. Pb speciation and soil physico‐chemical properties are the main factors determining the EKR effect. Higher voltage and longer processing time result in better remediation effects. Pre‐saturating soil samples with EDTA‐2Na is favorable for reducing energy consumption. [ABSTRACT FROM AUTHOR]