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A novel Ir−Mn dual‐atom electrocatalyst is synthesized by a facile ion‐exchange method by incorporating Ir in SrMnO3, which yields an extremely high activity and stability for the oxygen evolution reaction (OER). The ion exchange process occurs in a self‐limitation way, which favors the formation of Ir−Mn dual‐atom in the IrMnO9 unit. The incorporation of Ir modulates the electronic structure of both Ir and Mn, thereby resulting in a shorter distance of the Ir−Mn dual‐atom (2.41 Å) than the Mn−Mn dual‐atom (2.49 Å). The modulated Ir−Mn dual‐atom enables the same spin direction O (↑) of the adsorbed *O intermediates, thus facilitating the direct coupling of the two adsorbed *O intermediates to release O2 via the oxygen‐oxygen radical coupling mechanism. Electrochemical tests reveal that the Ir‐SrMnO3 exhibits a superior OER's activity with a low overpotential of 207 mV at 10 mA cm−2 and achieves a mass specific activity of 1100 A gIr−1 at 1.5 V. The proton‐exchange‐membrane water electrolyzer with the Ir‐SrMnO3 catalyst exhibits a low electrolysis voltage of 1.63 V at 1.0 A cm−2 and a stable 2000‐h operation with a decay of only 15 μV h−1 at 0.5 A cm−2. [ABSTRACT FROM AUTHOR]

Metal phase molybdenum disulfide (1T-MoS2) is considered a promising electrocatalyst for the hydrogen evolution reaction (HER). In this work, an interface engineering-induced strategy is reported to prepare a 1T-MoS2/NiS heterostructure. The 1T-MoS2/NiS heterostructure exhibits an enhanced HER activity compared with that of the 1T-MoS2 in 1.0 M KOH. It achieves an overpotential of 0.12 V at a current density of 10 mA cm−2 with a Tafel slope of 69 mV dec−1. The density functional theory (DFT) calculations reveal that the interface engineering-induced 1T-MoS2/NiS heterostructure exhibits regulated electronic states of the S sites in 1T-MoS2, thus promoting the HER activity. This work demonstrates that tuning the electronic structure through interface engineering to enhance the intrinsic activity of electrocatalysts is a feasible strategy. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 (CO2RR) to value‐added chemicals is an effective way to harvest renewable energy and utilize carbon dioxide. However, the electrocatalysts for CO2RR suffer from insufficient activity and selectivity due to the limitation of CO2 activation. In this work, a Ni‐doped Bi nanosheet (Ni@Bi‐NS) electrocatalyst is synthesized for the electrochemical reduction of CO2 to HCOOH. Physicochemical characterization methods are extensively used to investigate the composition and structure of the materials. Electrochemical results reveal that for the production of HCOOH, the obtained Ni@Bi‐NS exhibits an equivalent current density of 51.12 mA cm−2 at −1.10 V, which is much higher than the pure Bi‐NS (18.00 mA cm−2 at −1.10 V). A high Faradaic efficiency over 92.0 % for HCOOH is achieved in a wide potential range from −0.80 to −1.10 V, and particularly, the highest efficiency of 98.4 % is achieved at −0.90 V. Both experimental and theoretical results reveal that the superior activity and selectivity are attributed to the doping effect of Ni on the Bi nanosheet. The density functional theory calculation reveals that upon doping, the charge is transferred from Ni to the adjacent Bi atoms, which shifts the p‐orbital electronic density states towards the Fermi level. The resultant strong orbital hybridization between Bi and the π* orbitals of CO2 facilitates the formation of *OCHO intermediates and favors its activation. This work provides an effective strategy to develop active and selective electrocatalysts for CO2RR by modulating the electronic density state. [ABSTRACT FROM AUTHOR]

An electrochemical biosensor based on chitosan- and thioctic-acid-modified nanoporous gold (NPG) co-immobilization glycerol kinase (GK) and glycerol-3-phosphate oxidase (GPO) was constructed for glycerol determination in wine. The NPG, with the properties of porous microstructure, large specific surface area, and high conductivity, was beneficial for protecting the enzyme from inactivation and denaturation and enhancing electron transfer in the modified electrode. The co-immobilization of the enzyme by chitosan-embedding and thioctic-acid-modified NPG covalent bonding was beneficial for improving the catalytic performance and stability of the enzyme-modified electrode. Ferrocene methanol (Fm) was used as a redox mediator to accelerate the electron transfer rate of the enzyme-modified electrode. The fabricated biosensor exhibited a wide determination range of 0.1–5 mM, low determination limit of 77.08 μM, and high sensitivity of 9.17 μA mM−1. Furthermore, it possessed good selectivity, repeatability, and stability, and could be used for the determination of glycerol in real wine samples. This work provides a simple and novel method for the construction of biosensors, which may be helpful to the application of enzymatic biosensors in different determination scenarios. [ABSTRACT FROM AUTHOR]

Objective. The present study aimed at investigating the efficacy and safety of intravenous administration of cytarabine supplemented with idarubicin in treating acute myeloid leukemia (AML) patients undergoing first attack and its effects on serum levels of cell adhesion molecules, cytokines in response to inflammation, and T cell subset populations in acute myeloid leukemia (AML) patients undergoing first attack. Methods. A total of 88 AML patients eligible for inclusion and exclusion criteria participated in the study and were randomly assigned into the control group (n = 44) in which the patients received intravenous administration of cytarabine and daunorubicin and the study group (n = 44) in which the patients received intravenous administration of cytarabine and idarubicin. Clinical response, incidence of adverse reactions, and quality of life 3 months after therapy were evaluated. Soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), IL-10, and IL-35 were measured by ELISA methods. Phenotypic characteristics of T cell subsets including CD4+, CD8+, CD4+IL-10 Tregs, and CD4+CD25+CD127−Foxp3+ Tregs were analyzed by flow cytometry. Results. The clinical response rate of the study group was better than that of the control group (65.91% vs. 45.45%) (P < 0.05). After treatment, the study group revealed significantly lower levels of sICAM-1, sVCAM-1, IL-10, and IL-35, a lower proportion of Tregs, a higher rate of CD4+/CD8+ T cells, along with increased scores of the Karnofsky Performance Scale (KPS) compared with the control group (P < 0.05). The incidence rate of adverse reactions in the study group was lower than that in the control group (34.09% vs. 61.36%) (P < 0.05). Conclusion. These findings demonstrate that intravenous administration of cytarabine supplemented with idarubicin can improve the immune function and quality of life of AML patients, and this combination drug therapy is effective and safe for AML. [ABSTRACT FROM AUTHOR]

A novel organic molecule, 2,4,6‐tris[1‐(trimethylamonium)propyl‐4‐pyridiniumyl]‐1,3,5‐triazine hexachloride, was developed as a reversible six‐electron storage electrolyte for use in an aqueous redox flow battery (ARFB). Physicochemical characterization reveals that the molecule evolves from a radical to a biradical and finally to a quinoid structure upon accepting four electrons. Both the diffusion coefficient and the rate constant were sufficiently high to run a flow battery with low concentration and kinetics polarization losses. In a demonstration unit, the assembled flow battery affords a high specific capacity of 33.0 Ah L−1 and a peak power density of 273 mW cm−2. This work highlights the rational design of electroactive organics that can manipulate multi‐electron transfer in a reversible way, which will pave the way to development of energy‐dense, manageable and low‐cost ARFBs. [ABSTRACT FROM AUTHOR]

Abstract Background Cooperation of constituents of the ubiquitin proteasome system (UPS) with chaperone proteins in degrading proteins mediate a wide range of cellular processes, such as synaptic function and neurotransmission, gene transcription, protein trafficking, mitochondrial function and metabolism, antioxidant defence mechanisms, and apoptotic signal transduction. It is supposed that constituents of the UPS and chaperone proteins are recruited into aggresomes where aberrant and potentially cytotoxic proteins may be sequestered in an inactive form. Results To determinate the proteomic pattern of synthetic proteasome inhibitor (PSI)-induced inclusions in PC12 cells after proteasome inhibition by PSI, we analyzed a fraction of PSI-induced inclusions. A proteomic feature of the isolated fraction was characterized by identification of fifty six proteins including twenty previously reported protein components of Lewy bodies, twenty eight newly identified proteins and eight unknown proteins. These proteins, most of which were recognized as a profile of proteins within cellular processes mediated by the UPS, a profile of constituents of the UPS and a profile of chaperone proteins, are classed into at least nine accepted categories. In addition, prolyl-4-hydroxylase beta polypeptide, an endoplasmic reticulum member of the protein disulfide isomerase family, was validated in the developmental process of PSI-induced inclusions in the cells. Conclusions It is speculated that proteomic characterization of an isolated fraction of PSI-induced inclusions in PC12 cells might offer clues to appearance of aggresomes serving as a cellular defensive response against proteasome inhibition.

The overuse of tetracycline results in a threat to human, poultry and livestock health. An enzymatic electrochemical biosensor is an ideal alternative method for accurate and rapid tetracycline detection, while the unstable and easily deactivated nature of the enzyme limits its development. To overcome these limitations, a highly sensitive enzymatic electrochemical biosensor for the determination of tetracycline is developed in this work based on a complex enzyme which was constructed using a mesoporous carbon sphere@UiO-66-NH2 (MCS@UiO-66-NH2) core–shell composite with embedded laccase (Lac). Compared to pure MCS and UiO-66-NH2, the MCS@UiO-66-NH2 core–shell composite has an advantageous mesoporous structure (pore diameter >8 nm), which is suitable for the immobilization of small laccase. The biosensor based on the complex enzyme exhibits a superior activity and enhanced stability as compared with that made using a pure enzyme because the mesoporous structure of the MCS@UiO-66-NH2 composite can effectively protect the laccase against inactivation and denaturation. Besides, its high specific surface area and good conductivity are beneficial to enzyme immobilization and electron transfer in the modified electrode. The biosensor based on this complex enzyme exhibits a relatively low detection limit of 8.94 × 10−7 mol L−1 and a detection range of 1.0 × 10−6–6.0 × 10−5 mol L−1 for tetracycline detection. Furthermore, the developed biosensor possesses good long-term stability, selectivity and reproducibility, indicating its potential application for tetracycline determination in actual food. This research work provides a prospective solution to resolve the stability and inactivation problems of enzymatic electrochemical biosensors in different application scenarios. [ABSTRACT FROM AUTHOR]

The gas-induced transformation of organic–inorganic halide perovskites shows unprecedented phenomena and applications in the area of optoelectronics. In this study, the chemical origins of the gas-induced dimensional transformation (GIDT) of MAPbI3 have been investigated within CH3NH2 (MA), CH3(CH2)5NH2 (C6) and (CH3CH2)3N (C6′) atmospheres. With the exposure of the as-synthesized MAPbI3 perovskite thin film to the C6 gas, the rapid displacement of the MA+ cations by the C6+ cations is achieved, thus inducing the MAPbI3 thin film structure to turn from a three-dimensional motif to two-dimensional (CH3(CH2)5NH3)2PbI4. By comparison, no response is observed when the same process is carried out in the presence of the tertiary amine C6′ gas. With MA acting as a coinduction conversion agent, the MAPbI3 film transfers to a quasi-2D perovskite structure within MA and C6 mixture atmosphere, while it changes to a one-dimensional (C6H15NH)PbI3 chain as MA combines with the C6′ gas, showing an effective mixed amine strategy for GIDT. Interestingly, the obtained quasi-2D perovskite films display tuneable absorption and emission luminescent characters associated with the volume ratios of MA/C6-mixed amines. [ABSTRACT FROM AUTHOR]

Multiple-ring naphthalenediammonium is employed for the first time to overcome the intrinsic instability of β-CsPbI3 perovskite via anchoring the ammonium groups occupying A-site vacancies. It improves charge transport and moisture stability giving out a champion power conversion efficiency of 16.69% for an excellent inorganic perovskite solar cell. [ABSTRACT FROM AUTHOR]

Abstract: Electro‐oxidation of glycerol affords a totally green route to produce high value‐added chemicals. Herein, we report a study on glycerol electro‐oxidation over a series of graphene nanosheet supported Pt (Pt/GNS), PtNi (PtNi/GNS), PtRu (PtRu/GNS), PtRh (PtRh/GNS), PtRuNi (PtRuNi/GNS), and PtRhNi (PtRhNi/GNS) catalysts in alkaline solution. The activity of the catalysts was evaluated by cyclic voltammetry, linear sweep voltammetry, and chronoamperometric measurements. The PtRh/GNS and PtRhNi/GNS catalysts exhibited superior activity in terms of higher current densities and lower onset potentials. The products of glycerol oxidation formed at potentials of −0.4, −0.1, and 0.2 V, were systematically analyzed by high performance liquid chromatography (HPLC). Five compounds as products from glycerol electro‐oxidation catalyzed by the prepared materials were found, including glyceraldehyde, glycolic acid, tartronic acid, glyceric acid and oxalate acid. The product distribution at the different potentials was investigated for all catalysts. A maximum glycolic acid selectivity of 65.4 % was obtained for the Pt/GNS catalyst at 0.2 V while a maximum glyceric acid selectivity of 47.7 % was achieved using the PtNi/GNS catalyst at −0.1 V. It was found that the introduction of Ru facilitated the formation of C3 products while the addition of Rh was beneficial for the formation of C2 products. Based on HPLC results, the pathways of glycerol electro‐oxidation by the prepared catalysts were proposed. [ABSTRACT FROM AUTHOR]

Background Autoimmune diseases in children are rare and can be difficult to diagnose. Autoimmune lymphoproliferative syndrome (ALPS) is a well-characterized pediatric autoimmune disease caused by mutations in genes associated with the FAS-dependent apoptosis pathway. In addition, various genetic alterations are associated with the ALPS-like phenotype. Objective The aim of the present study was to elucidate the genetic cause of the ALPS-like phenotype. Methods Candidate genes associated with the ALPS-like phenotype were screened by using whole-exome sequencing. The functional effect of the identified mutations was examined by analyzing the activity of related signaling pathways. Results A de novo heterozygous frameshift mutation of TNF-α–induced protein 3 (TNFAIP3, A20), a negative regulator of the nuclear factor κB pathway, was identified in one of the patients exhibiting the ALPS-like phenotype. Increased activity of the nuclear factor κB pathway was associated with haploinsufficiency of TNFAIP3 (A20). Conclusion Haploinsufficiency of TNFAIP3 (A20) by a germline heterozygous mutation leads to the ALPS phenotype. [ABSTRACT FROM AUTHOR]

Cancer cells frequently express glycans at different levels and/or with fundamentally different structures from those expressed by normal cells, and therefore elucidation and manipulation of these glycosylations may provide a beneficial approach to cancer therapy. However, the relationship between altered glycosylation and causal genetic alteration(s) is only partially understood. Here, we employed a unique approach that applies comprehensive glycomic analysis to a previously described multistep tumorigenesis model. Normal human astrocytes were transformed via the serial introduction of hTERT, SV40ER, H-RasV12, and myrAKT, thereby mimicking human brain tumor grades I-IV. More than 160 glycans derived from three major classes of cell surface glycoconjugates (N- and O-glycans on glycoproteins, and glycosphingolipids) were quantitatively explored, and specific glycosylation patterns related to malignancy were systematically identified. The sequential introduction of hTERT, SV40ER, H-RasV12, and myrAKT led to (i) temporal expression of pauci-mannose/mono-antennary type N-glycans and GD3 (hTERT); (ii) switching from ganglio- to globo-series glycosphingolipids and the appearance of Neu5Gc (hTERT and SV40ER); (iii) temporal expression of bisecting GlcNAc residues, α2,6-sialylation, and stage-specific embryonic antigen-4, accompanied by suppression of core 2 O-glycan biosynthesis (hTERT, SV40ER and Ras); and (iv) increased expression of (neo)lacto-series glycosphingolipids and fucosylated N-glycans (hTERT, SV40ER, Ras and AKT). These sequential and transient glycomic alterations may be useful for tumor grade diagnosis and tumor prognosis, and also for the prediction of treatment response. [ABSTRACT FROM AUTHOR]