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Fabricating highly oriented 2D nanosheet arrays is crucial for boosting their performance in electronics, catalysis, optics, and energy conversion, while it remains a challenge due to the high surface energy often leads to random aggregation or interlaced structure. In this study, it is found that the exposed facet of Fe2O3 can greatly influence the interface growth arrangement of bimetallic hydroxide (NiCo(OH)2) nanosheets. The NiCo(OH)2 nanosheets tend to parallel‐standing on the cubic and spindle Fe2O3 while random‐ and interlaced‐standing on the Fe2O3 hexagonal nanoplates and microspheres. The theoretical simulation further indicates the orientation of deposited hydroxide sheets is decided explicitly by the interfacial lattice match/mismatch. Compared to the common interlaced structure of nanosheets, the parallel‐standing nanosheet arrays reduce grain boundaries and improve the charge transfer efficiency. As a result, the derived NiCoP cages exhibit a promising oxygen evolution reaction performance with an overpotential of 255 mV at 10 mA cm−2, and the maximum current density of 400 mA cm−2 with the overpotential of 319 mV. [ABSTRACT FROM AUTHOR]

Tumor metastasis involves cells migrating directionally in response to external chemical signals. Reactive oxygen species (ROS) in the form of H2O2 has been demonstrated as a chemoattractant for neutrophils but its spatial characteristics in tumor microenvironment and potential role in tumor cell dissemination remain unknown. Here we investigate the spatial ROS distribution in 3D tumor spheroids and identify a ROS concentration gradient in spheroid periphery, which projects into a H2O2 gradient in tumor microenvironment. We further reveal the role of H2O2 gradient to induce chemotaxis of tumor cells by activating Src and subsequently inhibiting RhoA. Finally, we observe that the absence of mitochondria cristae remodeling proteins including the mitochondria-localized actin motor Myosin 19 (Myo19) enhances ROS gradient and promotes tumor dissemination. Myo19 downregulation is seen in many tumors, and Myo19 expression is negatively associated with tumor metastasis in vivo. Together, our study reveals the chemoattractant role of tumor microenvironmental ROS and implies the potential impact of mitochondria cristae disorganization on tumor invasion and metastasis. Synopsis: Loss of Myo19 promotes mitochondrial ROS production and the establishment of ROS concentration gradient in the spheroid periphery, which projects into a H2O2 gradient that induces chemotactic metastasis by activating Src and inhibiting RhoA. 3D tumor spheroids display a peripheral ROS gradient, which projects into an extracellular H2O2 gradient. Extracellular H2O2 gradient induces chemotaxis of tumor cells through Src activation and RhoA inhibition. Loss of Myo19 enhances the ROS gradient and promotes tumor dissemination in vitro and in vivo. Loss of Myo19 promotes mitochondrial ROS production and the establishment of ROS concentration gradient in the spheroid periphery, which projects into a H2O2 gradient that induces chemotactic metastasis by activating Src and inhibiting RhoA. [ABSTRACT FROM AUTHOR]

The massive use of fossil fuels releases a great amount of CO2, which substantially contributes to the global warming. For the global goal of putting CO2 emission under control, effective utilization of CO2 is particularly meaningful. Electrocatalytic CO2 reduction reaction (eCO2RR) has great potential in CO2 utilization, because it can convert CO2 into valuable carbon‐containing chemicals and feedstock using renewable electricity. The catalyst design for eCO2RR is a key challenge to achieving efficient conversion of CO2 to fuels and useful chemicals. For a typical heterogeneous catalyst, surface and interface engineering is an effective approach to enhance reaction activity. Herein, the development and research progress in CO2 catalysts with focus on surface and interface engineering are reviewed. First, the fundaments of eCO2RR is briefly discussed from the reaction mechanism to performance evaluation methods, introducing the role of the surface and interface engineering of electrocatalyst in eCO2RR. Then, several routes to optimize the surface and interface of CO2 electrocatalysts, including morphology, dopants, atomic vacancies, grain boundaries, surface modification, etc. are reviewed and representative examples are given. At the end of this review, we share our personal views in future research of eCO2RR. [ABSTRACT FROM AUTHOR]

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease. We previously revealed that the natural compound artemisitene (ATT) exhibits excellent broad anticancer activities without toxicity on normal tissues. Nevertheless, the effect of ATT on RA is undiscovered. Herein, we aim to study the effect and potential mechanism of ATT on RA management. Methods: A collagen‐induced arthritis (CIA) mouse model was employed to confirm the anti‐RA potential of ATT. Cell Counting Kit‐8 (CCK‐8) and 5‐ethynyl‐2'‐deoxyuridine (EdU) assays, cell cycle and apoptosis analysis, immunofluorescence, migration and invasion assays, quantitative real‐time PCR (RT‐qPCR), Western blot, RNA‐sequencing (RNA‐seq) analysis, plasmid construction and lentivirus infection, and methylated RNA immunoprecipitation and chromatin immunoprecipitation assays, were carried out to confirm the effect and potential mechanism of ATT on RA management. Results: ATT relieved CIA in mice. ATT inhibited proliferation and induced apoptosis of RA‐fibroblast‐like synoviocytes (FLSs). ATT restrained RA‐FLSs migration and invasion via suppressing epithelial–mesenchymal transition. RNA‐sequencing analysis and bioinformatics analysis identified intercellular adhesion molecule 2 (ICAM2) as a promoter of RA progression in RA‐FLSs. ATT inhibits RA progression by suppressing ICAM2/phosphoinositide 3‐kinase (PI3K)/protein kinase B (AKT)/p300 pathway in RA‐FLSs. Moreover, ATT inhibited methyltransferase‐like 3 (METTL3)‐mediated N6‐methyladenosine methylation of ICAM2 mRNA in RA‐FLSs. Interestingly, p300 directly facilitated METTL3 transcription, which could be restrained by ATT in RA‐FLSs. Importantly, METTL3, ICAM2 and p300 expressions in synovium tissues of RA patients were related to clinical characteristics and therapy response. Conclusions: We provided strong evidence that ATT has therapeutic potential for RA management by suppressing proliferation, migration and invasion, in addition to inducing apoptosis of RA‐FLSs through modulating METTL3/ICAM2/PI3K/AKT/p300 feedback loop, supplying the fundamental basis for the clinical application of ATT in RA therapy. Moreover, METTL3, ICAM2 and p300 might serve as biomarkers for the therapy response of RA patients. [ABSTRACT FROM AUTHOR]

A series of deferasirox derivatives of 1,2,4‐triazole (5 a–i,6 a–g) were designed and synthesized by the ring‐opening rearrangement reaction of phenyl hydrazine or its substituents and imines, compounds 5 d–i, 6 e–g are previously unknown. Obtained derivatives were characterized by IR, 1H NMR, 13C NMR, and Mass spectral. The antibacterial activities of all compounds against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Candida albicans and Aspergillus niger were experimentally evaluated. Most of them exhibited potential antimicrobial activity and promising antifungal activity. Especially, 6 f and 6 g showed the best antimicrobial activity (MIC90=0.125–2.0 μg/mL) against Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli, while compounds 6 c, 6 e showed excellent antifungal activity (MIC90=0.5–2.0 μg/mL). The molecular docking analysis further revealed that all the synthesized derivatives have shown potential binding affinities. [ABSTRACT FROM AUTHOR]

Background & Aim: Shortage of donor hepatocytes limits hepatocyte transplantation for clinical application. Induced hepatic stem cells (iHepSCs) have capacities of self‐renewal and bipotential differentiations. Here, we investigated whether iHepSCs could be extensively expanded, and whether they could differentiate into sufficient functional hepatocytes as donors for transplantation therapy after their extensive expansions. Methods: Murine extensively expanded iHepSCs (50‐55 passages) were induced to differentiate into iHepSC‐Heps under a chemically defined condition. iHepSC‐Heps were proved for carrying morphological hepatocyte characters and hepatocytic functions including low‐density lipoprotein uptake, glycogen storage, CLF secretion, ICG uptake and release, Alb secretion, urea synthesis and metabolism‐relative gene expressions respectively. Next, both iHepSCs and iHepSC‐Heps were transplanted into Fah‐/‐ mice respectively. Both liver repopulation and alleviation of liver function were compared between two transplantation groups. Results: Murine iHepSCs still maintained the capacities of self‐renewal and bipotential differentiations after extensive expansion. The efficiency for the functional hepatocyte differentiation from extensively expanded iHepSCs reached to 72.64%. Transplantations of both extensively expanded iHepSCs and iHepSC‐Heps resulted in liver engraftment in Fah‐/‐ mice. Survival rate of Fah‐/‐ mice recipients and level of liver repopulation were 50% and 20.32 ± 4.58% respectively in iHepSC‐Heps group, while 33% and 10.4 ± 4.3% in iHepSCs group. Conclusions: Extensively expanded iHepSCs can efficiently differentiate into hepatocytes in chemical defined medium. Transplantation of iHepSC‐Heps was more effective and more efficient than transplantation of iHepSCs in Fah‐/‐ mice. Our results suggested an innovative system to obtain sufficient hepatocytes through hepatic differentiation of iHepSCs generated by lineage reprogramming. [ABSTRACT FROM AUTHOR]

The quest for developing electrochemical energy‐storage and ‐conversion technologies continues to be a great impetus to develop cost‐effective, highly active, and electrochemically stable electrocatalysts for overcoming the activation energy barriers of the oxygen evolution reaction (OER). Co3O4 nanocrystals have great potential as OER catalysts, and research efforts on improving the catalytic activity of Co3O4 are currently underway in many laboratories. Herein, CoFe layered double hydroxide (LDH) nanosheets were directly grown on the active Co3O4 substrate to form nanohybrid electrocatalysts for OER. The CoFe LDH/Co3O4(6:4) nanohybrid exhibited superior catalytic performance with a low overpotential and a small Tafel slope in alkaline solution. The outstanding performance of the CoFe LDH/Co3O4(6:4) nanohybrid was primarily owing to the synergistic effects induced by the strongly coupled interface between CoFe LDH and Co3O4; this feature enhanced the intrinsic OER catalytic activity of the nanohybrid and favored fast charge transfer. Compared with other Co3O4‐based catalysts, the nanohybrid shows advantages and offers a feasible avenue for improving the activity of Co3O4‐based catalysts. [ABSTRACT FROM AUTHOR]

CuBi2O4 (CBO) is a promising photocathode for photoelectrochemical (PEC) water reduction, whereas the disadvantages of poor stability and severe charge recombination still hinder its application. In response, we designed a stabilized, efficient CBO/ZnSe/P25 (CBO/ZS/P25) photocathode with the CBO film modified by ZS and P25. As a result, this novel photocathode exhibited an outstanding current density of 0.43 mA/cm2, more than twice that of CBO. Systematic studies reveal that the high performance is attributed to heterojunction formation between ZS and P25, high electron mobility of ZS and hole extraction capacity of CBO. Besides, P25 protective layer can effectively blocks contact with the electrolyte and enhance the stability (retained nearly 90 % of the photocurrent after testing 5000s). Therefore, our results can provide an efficient strategy to design high performance CBO‐based photocathode material. [ABSTRACT FROM AUTHOR]

The development and design of a highly active and affordable nanostructured material as an efficient electrocatalyst for electrochemical oxygen evolution is a pressing necessity to realize industrial production of hydrogen by water electrolysis. Amorphous nanocomposites have recently attracted interest owing to their superior electrocatalytic activity derived from their unique structure. Herein, amorphous CoFe double hydroxides (Am‐CFDH) decorated with N‐doped carbon nanotubes (NCNTs) is synthesized by a facile and simple one‐pot approach under room temperature. Through electrochemical measurement, the bare Am‐CFDH nanocomposite already exhibits a comparable oxygen evolution reaction (OER) activity to the commercial IrO2 catalyst on account of its amorphous nature and the interaction between Co and Fe. The introduced NCNTs can provide better electrical conductivity, more anchoring sites, and functional groups for enhancing the transfer of electrons and reactants, preventing the agglomeration of Am‐CFDH to expose more active sites, and improving the synergistic effect between Am‐CFDH and NCNTs. Thus, the Am‐CFDH/NCNTs hybrid displays favorable durability beyond 20 h and advanced OER activity, owning a small overpotential of 270 mV at 10 mA cm−2 and a low Tafel slope of 56.88 mV dec−1 in alkaline medium. [ABSTRACT FROM AUTHOR]

Application of ZnO in the field of photoelectrochemical water splitting is limited because of its wide‐band‐gap and high recombination rate. Herein is reported the design of an efficient ZnO photoanode deposited with CoOx nanoparticles to achieve a heterojunction and oxygen vacancies. The CoOx nanoparticles with abundant oxygen vacancies were anchored onto the nanorod arrays by spin coating and calcination followed by a solvothermal treatment. CoOx nanoparticles serve the dual function of forming a p‐n heterojunction to facilitate the separation of photogenerated carriers, and act as a cocatalyst to decrease water oxidation barrier. Finally, oxygen vacancies increase the number of active redox sites and act as hole traps, enabling their migration to the electrode/electrolyte interface. The composite photoanode exhibits a high incident photon‐to‐current conversion efficiency (76.7 % at 350 nm), which is twice that of pristine ZnO, and a photoconversion efficiency of 0.68 % (0.73 V versus RHE). The current approach can be expanded to fabricate other efficient photocatalysts. Lose some to gain some: A composite ZnO nanorod array photoanode is constructed by coating with CoOx nanoparticles and inclusion of oxygen vacancies. A p–n heterojunction is formed at the CoOx/ZnO interface, which improves carrier separation and oxygen evolution kinetics (cocatalyst). The oxygen vacancies support hole trapping and their transport to the electrode/electrolyte interface, thereby significantly improving the water oxidation process. [ABSTRACT FROM AUTHOR]

This research was designed to investigate the fracture healing pattern in a rheumatoid arthritis (RA) rat model. A mid‐shaft femur fracture (RA + F) model and normal fracture (NF) model as control were established. Micro‐CT, H&E staining, TB staining, SO staining, tartrate‐resistant acid phosphates, and immunohistochemistry test were performed. In the micro‐CT images and H&E stains, fracture gaps were evident in the RA + F group 4 and 8 weeks after fracture. In detail, the bone mineral density, the ratio of bone volume to tissue volume, and trabecular thickness of the RA + F group were significantly lower than those of the NF group at all time points. Trabecular number value was significantly lower in the RA + F group 4 weeks after surgery in comparison with that of the NF group. Furthermore, the structure model index test result of the RA + F group was significantly higher than that of the NF group at all time points. TB staining and SO staining test results showed that the NF group had more cartilaginous callus in the earlier stage of bone healing process (4 weeks), and less cartilage callus formation in the later stage (8 weeks) in comparison with that of the RA + F group. Osteoclasts statistics score in the NF group were obviously lower than that of the RA + F group at all time points. MMP‐3 and OPN protein levels of the fracture area in the RA + F group were significantly higher than those in the NF group. This study improves the understanding of the bone healing characteristics in patients with RA. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2876–2885, 2018. [ABSTRACT FROM AUTHOR]

Abstract: Highly efficient and precious metal free catalysts for the hydrogen evolution reaction (HER) are of vital importance for renewable energy technologies. Nevertheless, developing simple methods for the synthesis of highly active and super‐durable electrocatalysts at low cost for HER still remains a major challenge. In this work, high temperature pyrolysis of (NH4)6Mo7O24 ⋅ 4H2O, NaH2PO4 and multi‐walled carbon nanotubes (MWCNTs) in Ar atmosphere is carried out to obtain phosphorus dually doped MoO2 nanosheets (MoO2 NSs) and MWCNTs hybrids (MoO2Px NSs/P‐MWCNTs), which can serve as excellent electrocatalyst for HER. In 0.5 M H2SO4, the hybrid material catalyzes HER with an onset potential of −27 mV (vs. reversible hydrogen electrode, RHE), Tafel slope of 45 mV dec−1, and an overpotential at 10 mA cm−2 of only 57 mV. Additionally, it displays favorable stability over 50 h in acidic media. [ABSTRACT FROM AUTHOR]

Abstract: Bismuth vanadate (BiVO4) has triggered extensive interest in photoelectrochemical (PEC) water splitting, owing to its narrow band gap and sufficiently positive valence band. However, some defects still exist to block the solar utilization efficiency and hydrogen evolution kinetics. Herein, the NiMoO4 semiconductor is combined with a BiVO4 photoanode, for the first time, and excellent PEC performance is achieved on the basis of heterojunction formation and favorable conductivity of NiMoO4. In addition, it has been demonstrated that NiMoO4 promotes the light absorption ability, charge separation efficiency, and surface charge‐transfer efficiency comprehensively. To further improve the photoconversion efficiency, cobalt phosphate, as an oxygen evolution reaction cocatalyst, is deposited on the above electrode and achieves a much enhanced utilization efficiency of 1.18 %, with a photocurrent density of 5.3 mA cm−2 at 1.23 V versus a reversible hydrogen electrode; this exceeds most results reported to date. This rational and unique photoanode construction provides a new thread for the photoelectrode designation. [ABSTRACT FROM AUTHOR]

Abstract: The photoelectrochemical (PEC) water‐splitting efficiency of a hematite‐based photoanode is still far from the theoretical value due to its poor surface reaction kinetics and high density of surface trapping states. To solve these drawbacks, a photoanode consisting of NiO nanoparticles anchored on a gradient phosphorus‐doped α‐Fe2O3 nanorod (NR) array (NiO/P‐α‐Fe2O3) was fabricated to achieve optimal light absorption and charge separation, as well as rapid surface reaction kinetics. Specifically, a photoanode with the NR array structure allowed a high mass‐transport rate to be achieved, while phosphorus doping effectively decreased the number of surface trapping sites and improved the electrical conductivity of α‐Fe2O3. Furthermore, the p–n junction that forms between NiO and P‐α‐Fe2O3 can further improve the PEC performance due to efficient hole extraction and the water oxidization catalytic activity of NiO. Consequently, the NiO/P‐α‐Fe2O3 NR photoanode produced a high photocurrent density of 2.08 mA cm−2 at 1.23 V versus a reversible hydrogen electrode and a 110 mV cathodic shift of the onset potential. This rational design of structure offers a new perspective in exploring high‐performance PEC photoanodes. [ABSTRACT FROM AUTHOR]