Multi-layer core-shell metal oxide/nitride/carbon and its high-rate electroreduction of nitrate to ammonia.

The electroreduction of nitrate to ammonia is both an alternative strategy to industrial Haber-Bosch ammonia synthesis and a prospective idea for changing waste (nitrate pollution of groundwater around the world) into valuable chemicals, but still hindered by its in-process strongly competitive hydrogen evolution reaction (HER), low ammonia conversion efficiency, and the absence of stability and sustainability. Considering the unique electronic structure of anti-perovskite structured Fe4N, a tandem disproportionation reaction and nitridation-carbonation route for building a multi-layer core-shell oxide/nitride/C catalyst, such as MoO2/Fe4N/C, is designed and executed, in which abundant Fe-N active sites and rich phase interfaces are in situ formed for both suppressing HER and fast transport of electrons and reaction intermediates. As a result, the sample's NO3RR conversion displays a very high NH3 yield rate of up to 11.10 molNH3 gcat.-1 h-1 (1.67 mmol cm-2 h-1) with a superior 99.3% faradaic efficiency and the highest half-cell energy efficiency of 30%, surpassing that of most previous reports. In addition, it is proved that the NO3RR assisted by the MoO2/Fe4N/C electrocatalyst can be carried out in 0.50-1.00 M KNO3 electrolyte at a pH value of 6-14 for a long time. These results guide the rational design of highly active, selective, and durable electrocatalysts based on anti-perovskite Fe4N for the NO3RR.

Surface oxygen vacancy engineering on TiO2 (101) via ALD technology for simultaneously enhancing charge separation and transfer.

Titanium oxide molecular layers containing extensive SOV content (11.4-16.2%) have been constructed on (101) TiO2 nanotubes through a precisely controlled atomic layer deposition technique, in which the charge separation efficiency and surface charge transfer efficiency are increased to 28.2% and 89.0%, respectively, about 17 and 2 times those of the initial TiO2 nanotubes.

Artesunate ameliorates osteoarthritis cartilage damage by updating MTA1 expression and promoting the transcriptional activation of LXA4 to suppress the JAK2/STAT3 signaling pathway.

The objective of this study was to discuss the mechanism of artesunate (ART) in improving cartilage damage in osteoarthritis (OA) by regulating the expression levels of metastatic tumor antigen 1 (MTA1), lipoxin A4 (LXA4) and the downstream JAK2/STAT3 signaling pathway. The OA model in vitro was constructed by stimulating chondrocytes for 24 h with 10 ng/mL interleukin (IL)-1ß, and cell proliferation and apoptosis, expression levels of Aggrecan, MTA1, LXA4, MMP3, MMP13 and Collagen II, and inflammatory cytokines in the culture supernatants were examined. Histopathological changes, inflammatory response and chondrocyte apoptosis of the cartilage tissues of OA mice were performed. In vitro cell experiments, ART enhanced cell proliferation capacity, accompanied by decreased apoptosis rate, decreased expression of MMP-3 and MMP-13, elevated expression of Collagen II and Aggrecan, as well as reduced levels of IL-6 and TNF-α in the cell supernatant. ART also ameliorated IL-1ß-induced chondrocyte damage by upregulating MTA1. The LXA4 promoter region had two potential binding sites for MTA1. There was a positive correlation between MTA1 and LXA4. MTA1 enhanced the expression of LXA4 through transcription and blocked the activation of the JAK2/STAT3 signaling pathway. In vivo animal model experiments further showed that ART treatment alleviated cartilage tissue damage in OA model mice by upregulating MTA1. Our study demonstrates that ART improves the cartilage damage of OA by upregulating MTA1 expression and promoting the transcriptional activation of LXA4, and further blocking the JAK2/STAT3 signaling pathway.

Improve biomechanical stability using intramedullary nails with femoral neck protection in femoral shaft fractures.

BACKGROUND AND OBJECTIVE: Elderly patients treated for femoral shaft fractures have a higher risk of hip fracture. We hypothesized that intramedullary nails protecting the femoral neck can improve mechanical strength and reduce the risk of subsequent hip fracture. This study aims to analyze the biomechanical stability using intramedullary nails with or without femoral neck protection through finite element analysis. METHODS: Thirty finite element models (FEMs) were established, including five different conditions of femoral shaft fracture: Fracture healing, Proximal fractures (Transverse and oblique), Distal fractures (Transverse and oblique), and five different fixation methods. Femoral neck protection groups: cephalomedullary nail (CN), reconstruction nail (RN); No femoral neck protection groups: type-1 of antegrade intramedullary nail (AIN-1), type-2 of antegrade intramedullary nail (AIN-2), and retrograde intramedullary nail (RIN). The maximum stress of bone and internal fixation in the femoral neck region for all type of fixation were calculated to evaluate the biomechanical stability. RESULTS: Maximum equivalent stress values of bone in the femoral neck region for five different conditions of femoral shaft fracture: AIN-2 (77.23 MPa) >RIN (77.15 MPa) > AIN-1 (76.71 MPa) > CN (60.74 MPa) > RN (57.66 MPa) for the fracture healing; RIN (80.05 MPa) > AIN-1 (79.15 MPa) > AIN-2(78.77 MPa) > RN (65.16 MPa) > CN (65.03 MPa) for the proximal transverse fracture; RIN (80.10 MPa) > AIN-2 (79.36 MPa) > AIN-1 (79.18 MPa) > RN (65.09 MPa) > CN (64.96 MPa) for the proximal oblique fracture; RIN (80.24 MPa) > AIN-2 (79.68 MPa) > AIN-1 (79.33 MPa) > CN (65.02 MPa) > RN (64.76 MPa) for the distal transverse fracture; RIN (80.23 MPa) > AIN-2 (79.61 MPa) > AIN-1 (79.35 MPa) > CN (65.06 MPa) > RN (64.76 MPa) for the distal oblique fracture. Maximum equivalent stress of internal fixation in the femoral neck region is greater than the maximum stress of bone and avoids stress concentration of bone for the femoral neck protection groups (CN and RN). CONCLUSIONS: Intramedullary nails with femoral neck protection in the treatment of femoral shaft fractures improve mechanical strength and prevent secondary hip fractures and decrease the overall risk of reoperation postoperatively.

Atomically Dispersed Cu Sites on Dual-Mesoporous N-Doped Carbon for Efficient Ammonia Electrosynthesis from Nitrate.

The industrial Haber-Bosch process for ammonia synthesis is extremely important in modern society. However, it is energy intensive and leads to severe pollution, which has motivated eco-friendly NH3 synthesis research. Electroreduction of contaminant nitrate ions back to NH3 is an effective complement but is still limited by low NH3 yields and nitrate-to-NH3 selectivities. In this study, the electrochemical nitrate reduction reaction (NTRR) is carried out over a single-atom Cu catalyst. Atomically dispersed Cu sites anchored on dual-mesoporous N-doped carbon framework display excellent NTRR performance with NH3 production rate of 13.8 mol NH 3 gcat -1 h-1 and NO3 - -to-NH3 faradaic efficiency (FE) of 95.5 % at -1.0 V. Cu-N-C catalyst can sustain continuous 120 h NTRR test in the simulated NH3 synthesis scenarios with large current density (about 200 mA cm-2 ) and amplified volume of NO3 - solution (9 times). Theoretical calculations reveal that atomically dispersed Cu1 -N4 sites reduce the energy barrier of potential-determining step in NTRR and promote the decomposition of primary intermediate in NO3 - -to-N2 process. These findings provide a guideline for the rational design of highly active, selective and durable electrocatalysts for the NTRR.

Total glycosides from Eucommia ulmoides seed promoted osteogenic differentiation of adipose-derived mesenchymal stem cells and bone formation in ovariectomized rats through regulating Notch signaling pathway.

BACKGROUND: Osteoporosis (OP) is a well-known chronic degenerative disease, with impaired mesenchymal stem cells (MSCs) function and suppressed osteogenic differentiation. Total glycosides from Eucommia ulmoides seed (TGEUS) was a Chinese medicine and have rich pharmacological effects. This study was designed to explore the mechanism of TGEUS in promoting osteogenic differentiation and bone formation in ovariectomized (OVX) rats. METHODS: Adipose-derived mesenchymal stem cells (ADSCs) were isolated and treated with different concentration of TGEUS. Cell viability was assessed using cell counting kit-8 (CCK-8) assay. Osteogenic capacity was identified by ALP staining and ARS staining. Moreover, RNA sequencing between control and TGEUS treated ADSCs were further performed to reveal the mechanism of TGEUS in promoting osteogenic differentiation. The expression of Jag1, Lfng and Hey1 were measured using quantitative real-time polymerase chain reaction (qRTPCR). Osteogenic markers were further assessed by western blot. DAPT and NICD were further used to identify whether Notch signaling pathway involved into TGEUS promoting osteogenic differentiation of ADSCs. Ovariectomy-induced bone loss rats model was established and divided into three groups: sham, OVX and OVX + TGEUS groups. HE staining and immunohistochemical staining were further performed to identify whether TGEUS could promote bone formation. RESULTS: TGEUS treatment significantly enhanced the cell viability and ALP activity than control group, the optimal dose of TGEUS was 5 µM. We selected 5 µM TGEUS for further study. TGEUS significantly enhanced ALP activity and calcium deposition than that of control group. Activation of Notch signaling fully blocked TGEUS-induced osteogenic differentiation of ADSCs. Following TGEUS treatment, the trabecular bone of the rats was significantly increased, thickened, and more connected compared to the OVX group. With the treatment of TGEUS, the expression of Osterix (Osx), Osteocalcin (OCN) and RUNX Family Transcription Factor 2 (RUNX2) increased than OVX group. CONCLUSION: TGEUS enhanced osteogenic differentiation of ADSCs and promoted bone formation in ovariectomy-induced bone loss rats. Our study broadened the understanding of TGEUS as a therapeutic target against osteoporosis.

RETRACTED: Elevated microRNA-125b promotes inflammation in rheumatoid arthritis by activation of NF-κB pathway.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. Concerns were raised about the similarities between the background of the Western Blots from Figures 4B and 4D. Also, given the comments of Dr Elisabeth Bik regarding this article "... the Western blot bands in all 400+ papers are all very regularly spaced and have a smooth appearance in the shape of a dumbbell or tadpole, without any of the usual smudges or stains. All bands are placed on similar looking backgrounds, suggesting they were copy/pasted from other sources, or computer generated", the journal requested the authors to provide the raw data. However, the authors were not able to fulfil this request and therefore the Editor-in-Chief decided to retract the article.