Nanozymes have become a new generation of antibiotics with exciting broad-spectrum antibacterial properties and negligible biological toxicity. However, their inherent low catalytic activity limits their antibacterial properties. Herein, Cu single-atom sites/N doped porous carbon (Cu SASs/NPC) is successfully constructed for photothermal-catalytic antibacterial treatment by a pyrolysis-etching-adsorption-pyrolysis (PEAP) strategy. Cu SASs/NPC have stronger peroxidase-like catalytic activity, glutathione (GSH)-depleting function, and photothermal property compared with non-Cu-doped NPC, indicating that Cu doping significantly improves the catalytic performance of nanozymes. Cu SASs/NPC can effectively induce peroxidase-like activity in the presence of H 2 O 2 , thereby generating a large amount of hydroxyl radicals (•OH), which have a certain killing effect on bacteria and make bacteria more susceptible to temperature. The introduction of near-infrared (NIR) light can generate hyperthermia to fight bacteria, and enhance the peroxidase-like catalytic activity, thereby generating additional •OH to destroy bacteria. Interestingly, Cu SASs/NPC can act as GSH peroxidase (GSH-Px)-like nanozymes, which can deplete GSH in bacteria, thereby significantly improving the sterilization effect. PTT-catalytic synergistic antibacterial strategy produces almost 100% antibacterial efficiency against Escherichia coli ( E. coli ) and methicillin-resistant Staphylococcus aureus ( MRSA ). In vivo experiments show a better PTT-catalytic synergistic therapeutic performance on MRSA-infected mouse wounds. Overall, our work highlights the wide antibacterial and anti-infective bio-applications of Cu single-atom-containing catalysts.

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Background Complex immune-brain interactions that affect neural development, survival and function might have causal and therapeutic implications for psychiatric illnesses. However, previous studies examining the association between immune inflammation and schizophrenia (SCZ) have yielded inconsistent findings. Methods Comprehensive two-sample Mendelian randomization (MR) analysis was performed to determine the causal association between immune cell signatures and SCZ in this study. Based on publicly available genetic data, we explored causal associations between 731 immune cell signatures and SCZ risk. A total of four types of immune signatures (median fluorescence intensities (MFI), relative cell (RC), absolute cell (AC), and morphological parameters (MP)) were included. Comprehensive sensitivity analyses were used to verify the robustness, heterogeneity, and horizontal pleiotropy of the results. Results After FDR correction, SCZ had no statistically significant effect on immunophenotypes. It was worth mentioning some phenotypes with unadjusted low P-values, including FSC-A on NKT (β = 0.119, 95% CI = 0.044 ~ 0.194, P = 0.002), DN (CD4-CD8-) NKT %T cell (β = 0.131, 95% CI = 0.054 ~ 0.208, P = 9.03 × 10− 4), and SSC-A on lymphocytes (β = 0.136, 95% CI = 0.059 ~ 0.213, P = 5.43 × 10− 4). The causal effect of SCZ IgD on transitional was estimated to 0.127 (95% CI = 0.051 ~ 0.203, P = 1.09 × 10− 3). SCZ also had a causal effect on IgD+ %B cell (β = 0.130, 95% CI = 0.054 ~ 0.207, P = 8.69 × 10− 4), and DP (CD4+CD8+) %T cell (β = 0.131, 95% CI = 0.054 ~ 0.207, P = 8.05 × 10− 4). Furthermore, four immunophenotypes were identified to be significantly associated with SCZ risk: naive CD4+ %T cell (OR = 0.986, 95% CI = 0.979 ~ 0.992, P = 1.37 × 10− 5), HLA DR on CD14− CD16− (OR = 0.738 (95% CI = 0.642 ~ 0.849, P = 2.00 × 10− 5), CD33dim HLA DR+ CD11b− AC (OR = 0.631, 95% CI = 0.529 ~ 0.753, P = 3.40 × 10− 7) and activated & resting Treg % CD4 Treg (OR = 0.937, 95% CI = 0.906 ~ 0.970, P = 1.96 × 10− 4). Conclusions Our study has demonstrated the close connection between immune cells and SCZ by genetic means, thus providing guidance for future clinical research.

In this work, the Ti-6Al-4V alloy and ZrB 2 -SiC ultra-high temperature ceramic joint was brazed by TiCuZrNi amorphous filler at 910℃ with varied holding time. The element diffusion, microstructure and precipitation phase of the joints were analyzed in details. Reaction products in the joints were identified as β-Ti, (Ti,Zr) 2 (Cu,Ni), TiCu, Ti 2 Cu, TiC, Ti 5 Si 3 , TiB and TiB 2. The formation schemes of reaction products were investigated. The holding time has substantial impacts on interfacial microstructure and shear strength of joints. A maximum shear strength of 345 MPa of the joint was reached under a brazing temperature of 910℃ and holding time of 1200 s. It is also found that the shear strength depends on the amount of eutectic structure and brittle compounds in the joints.

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The structural disruption of mechanical barrier and dysfunction of immune barrier in intestinal, are important factors, that aggravate inflammatory bowel disease (IBD). To tackle this challenge, a multifunctional nanozyme capable of scavenging reactive oxygen species (ROS) and inhibiting ferroptosis or T cells differentiation for IBD therapy is here reported. In this work, zero‐valence selenium‐enriched Prussian blue nanozymes (Se‐HMPB nanozymes) are prepared via the hard template method. PB nanozymes with multi‐enzyme activities can effectively scavenge various ROS in inflammatory tissues. Meanwhile, the presence of selenium element endows the glutathione peroxidase activity of Se‐HMPB nanozymes, which can inhibit ferroptosis and reverse the lipid peroxidation of intestinal epithelial cells to protect the intestinal mechanical barrier in ulcerative colitis (UC) model. In addition, selenium supplementation can realize efficient inhibition on the differentiation of T cells in Crohn's disease (CD) model, regulating the intestinal immune barrier. Thus, the Se‐HMPB nanozymes reconstructed intestinal barrier via inhibiting ferroptosis and T cells differentiation in UC and CD models, depicting great potential to alleviate IBD.