Chlorine-anion doping induced multi-factor optimization in perovskites for boosting intrinsic oxygen evolution

The oxygen evolution reaction(OER) plays a crucial role in many electrochemical energy technologies,and creating multiple beneficial factors for OER catalysis is desirable for achieving high catalytic efficiency.Here,we highlight a new halogen-chlorine(Cl)-anion doping strategy to boost the OER activity of perovskite oxides.As a proof-of-concept,proper Cl doping at the oxygen site of LaFeO3(LFO) perovskite can induce multiple favorable characteristics for catalyzing the OER,including rich oxygen vacancies,increased electrical conductivity and enhanced Fe-O covalency.Benefiting from these factors,the LaFeO2.9-δCl0.1(LFOCl) perovskite displays significant intrinsic activity enhancement by a factor of around three relative to its parent LFO.This work uncovers the effect of Cl-anion doping in perovskites on promoting OER performance and paves a new way to design highly efficient electrocatalysts.

AZD1775 and anti-PD-1 antibody synergistically sensitize hepatoma to radiotherapy

Background:Radiation(IR)-induced DNA damage triggers cell cycle arrest and has a suppressive effect on the tumor microenvironment(TME).Wee1,a cell cycle regulator,can eliminate G2/M arrest by phosphorylating cyclin-dependent kinase 1(CDK1).Meanwhile,programed death-1/programed death ligand-1(PD-1/PDL-1)blockade is closely related to TME.This study aims to investigate the effects and mechanisms of Wee1 inhibitor AZD1775 and anti-PD-1 antibody(anti-PD-1 Ab)on radiosensitization of hepatoma.Methods:The anti-tumor activity of AZD1775 and IR was determined by 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenyltetrazolium bromide(MTT)assay on human and mouse hepatoma cells HepG2,Hepa1-6,and H22.The anti-hepatoma mechanism of AZD1775 and IR revealed by flow cytometry and Western blot in vitro.A hepatoma subcutaneous xenograft mice model was constructed on Balb/c mice,which were divided into control group,IR group,AZD1775 group,IR+AZD1775 group,IR+anti-PD-1 Ab group,and the IR+AZD1775+anti-PD-1 Ab group.Cytotoxic CD8^(+)T cells in TME were analyzed by flow cytometry.Results:Combining IR with AZD1775 synergistically reduced the viability of hepatoma cells in vitro.AZD1775 exhibited antitumor effects by decreasing CDK1 phosphorylation to reverse the IR-induced G2/M arrest and increasing IR-induced DNA damage.AZD1775 treatment also reduced the proportion of PD-1^(+)/CD8^(+)T cells in the spleen of hepatoma subcutaneous xenograft mice.Further studies revealed that AZD1775 and anti-PD-1 Ab could enhance the radiosensitivity of hepatoma by enhancing the levels of interferonγ(IFNγ)^(+)or Ki67^(+)CD8 T cells and decreasing the levels of CD8^(+)Tregs cells in the tumor and spleen of the hepatoma mice model,indicating that the improvement of TME was manifested by increasing the cytotoxic factor IFNγexpression,enhancing CD8^(+)T cells proliferation,and weakening CD8^(+)T cells depletion.Conclusions:This work suggests that AZD1775 and anti-PD-1 Ab synergistically sensitize hepatoma to radiotherapy by enhancing IR-induced DNA damage and improving cytotoxic CD8^(+)T cells in TME.