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Abstract Metal-organic frameworks (MOFs) benefitting from its controllable and diverse structure are a class of promising materials for diverse field. However, its directly employed for oxygen evolution reaction (OER) is still rare. Particularly, two-dimensional (2D) MOF nanosheets materials possess both advantages of 2D layered nanomaterials and MOFs, are considered as promising nanomaterials. Herein, we report a facile and scalable in situ hydrothermal synthesis of a 2D Co-based bimetallic MOFs (Co-Fe/Ni@HPA-MOF nanosheets), which can be stable in alkaline solution and directly adopted as highly efficient electrocatalysts. The Co-Ni@HPA-MOF can reach a current density of 10 mA cm−2 at low overpotential of 320 mV with a small Tafel slope of 58 mV dec−1, which is comparable to that of commercial RuO 2 (58 mV dec−1). The excellent electrocatalytic properties can be attributed to the 2D nanosheet and the coupling effect between Co and Ni, which provided large number of accessible active sites. The results highlight the great potential of utilizing MOF nanosheets for electrocatalysis, and will pave a way to develop more efficient 2D MOFs for diverse catalytic applications. Graphical abstract A facile and scalable in situ hydrothermal synthesis of a two dimensional Co-based bimetallic MOFs (Co-Fe/Ni@HPA-MOF nanosheets) was reported, which can be stable in alkaline solution and directly adopted as highly efficient electrocatalysts. fx1 Highlights • Two dimensional (2D) Co-based bimetallic metal-organic frameworks (MOFs) nanosheets were fabricated. • The Co-Ni@HPA-MOF nanosheet can reach a current density of 10 mA cm−2 at low overpotential of 320 mV. • The excellent electrocatalytic properties can be attributed to the coupling effect between Co and Ni. [ABSTRACT FROM AUTHOR]

Abstract Mesenchymal stem cells (MSCs) have been widely studied in the field of regenerative medicine with the potential to solve osteoporosis. Paired box 2 (Pax2), as a transcription factor, is the master regulator of embryogenesis and oncogenesis. However, the function of Pax2 in osteogenesis is unknown. Here, we reported for the first time that the expression of Pax2 gradually increased during osteogenic differentiation of mouse MSCs, and osteoprogenitor cells. However, detected in osteoblastic cells of mouse tibia, the expression of Pax2 in the embryonic stage was higher than that in adulthood. In C3H/10/T1/2 cells and compact bone-derived mouse MSCs (mMSCs), Pax2 knock-down inhibited the proliferation of these cells, down-regulated the expression of osteogenic marker genes, as well as repressed the ALP activity and mineralization. In addition, Pax2 enhanced the transcriptional activity of Runx2, and activated the MAPK pathway genes (ERK, JNK and p38). Furthermore, knock-down of Pax2 repressed the mMSCs-mediated bone regeneration in an ectopic bone formation model. In conclusion, Pax2 promotes osteogenesis of mouse MSCs, suggesting that Pax2 has a role in the pathophysiology of bone related diseases, and has potential application in bone tissue regeneration. Highlights • Knock-down of Pax2 inhibits the osteogenesis of mouse MSCs in vitro and in vivo. • Pax2 promotes the proliferation of mouse MSCs. • Pax2 enhances transcriptional activity of Runx2 and activates MAPK pathways. • Pax2 promotes the osteogenesis of mouse MSCs and may serve as a target for future clinical treatment. [ABSTRACT FROM AUTHOR]

Abstract Trio, the Rho guanine nucleotide exchange factor (Rho-GEF), plays diverse roles in cell migration, cell axon guidance and cytoskeleton reorganization. Conserved during evolution, Trio encodes two guanine nucleotide exchange factor domains (GEFs) and activates small GTPases. The Rho-family small GTPases RhoA and Rac1, which are target molecules of Trio, have been described to engage in craniofacial development and tooth formation. However, the exact role of Trio in tooth development remains elusive. In this study, we generated Wnt1-cre;Trio fl/fl mice to address the potential function of Trio in tooth development. Wnt1-cre;Trio fl/fl mice showed short root deformity as well as decreased expression of odontogenic makers such as RUNX2, OSX, OCN, and OPN. In vitro , Trio was silenced in human stem cells of dental papilla (SCAPs). Compared with the control group, the proliferation and migration ability in the experimental group was disrupted. After knocking down Trio in SCAPs, the cells showed phenotypes of poor odontogenic differentiation and weak mineralized nodules. To study the underlying mechanism, we investigated the p38 MAPK pathway and found that loss of Trio blocked the cascade transduction of p38 MAPK signaling. In conclusion, we identified Trio as a novel coordinator in regulating root development and clarified its relevant molecular events. Highlights • We have determined the role of Trio, a GTP exchange factor, in tooth development. • The Wnt1-cre;Trio fl/fl mice were created for in vivo study. • P38 MAPK pathway was found to be involved in Trio related root deformity. [ABSTRACT FROM AUTHOR]

In this paper, two novel zeolitic imidazole framework (ZIF) materials, ZIF-9 and ZIF-12 were firstly introduced as catalysts to activate PMS for Rhodamine B degradation. ZIF-9 and ZIF-12 have the same composition in metal ions (Co 2+ ) and organic linker, but show different structural topologies (SOD and RHO, respectively) and particle size. The two ZIFs were successfully synthesized and characterized via SEM and PXRD. Both ZIF-9 and ZIF-12 as the PMS activation catalysts were evaluated and compared, and the underlying mechanism was proposed. The nanoscale nature enables ZIF-9 a closer contact with PMS, which leading to degradation rate ZIF-9 > ZIF-12 at the time of 5 min (54.8% and 27.7%, respectively). And the degradation of ZIF-12 gradually caught up with ZIF-9 when the reaction time was longer, which can be attributed to the RHO topology and larger cage size of ZIF-12. The efficient degradation of RhB indicates that ZIF-9 and ZIF-12 can be promising heterogeneous catalyst to activate PMS for the degradation of RhB. [ABSTRACT FROM AUTHOR]