Here, an integrated cascade nanozyme with a formulation of Pt@PCN222-Mn is developed to eliminate excessive reactive oxygen species (ROS). This nanozyme mimics superoxide dismutase by incorporation of a Mn–[5,10,15,20-tetrakis(4-carboxyphenyl)porphyrinato]–based metal-organic framework compound capable of transforming oxygen radicals to hydrogen peroxide. The second mimicked functionality is that of catalase by incorporation of Pt nanoparticles, which catalyze hydrogen peroxide disproportionation to water and oxygen. Both in vitro and in vivo experimental measurements reveal the synergistic ROS-scavenging capacity of such an integrated cascade nanozyme. Two forms of inflammatory bowel disease (IBD; i.e., ulcerative colitis and Crohn’s disease) can be effectively relieved by treatment with the cascade nanozyme. This study not only provides a new method for constructing enzyme-like cascade systems but also illustrates their efficient therapeutic promise in the treatment of in vivo IBDs.

The global tobacco epidemic is still a devastating threat to public health. Toxic reactive oxygen species (ROS) in the cigarette smoke cannot be efficiently eliminated by currently available cigarette filters. The resultant oxidative stress causes severe lung injury and further diseases. To tackle this challenge, herein, a novel copper tannic acid coordination (CuTA) nanozyme is reported as a highly active and thermostable ROS scavenger. The CuTA nanozyme exhibits intrinsic superoxide dismutase‐like activity, catalase‐like activity, and hydroxyl radical elimination capacity. These synergistic antioxidant abilities make the CuTA nanozyme a promising candidate for the improvement of commercial cigarette filters. Mouse model results show that commercial cigarettes loaded with CuTA nanozyme efficiently scavenge ROS in the cigarette smoke, reduce oxidative stress–induced lung inflammation, and minimize the resultant acute lung injury. The developed CuTA nanozyme offers an efficient ROS scavenger with multiple antioxidant ability and opens up new opportunities for the modification of cigarette filters to reduce the toxic effects of cigarette smoke.

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Objectives To develop and evaluate the performance of a deep learning system based on convolutional neural network (ConvNet) to detect dental caries from oral photographs. Methods 3,932 oral photographs obtained from 625 volunteers with consumer cameras were included for the development and evaluation of the model. A deep ConvNet was developed by adapting from Single Shot MultiBox Detector. The hard negative mining algorithm was applied to automatically train the model. The model was evaluated for: (i) classification accuracy for telling the existence of dental caries from a photograph and (ii) localization accuracy for locations of predicted dental caries. Results The system exhibited a classification area under the curve (AUC) of 85.65% (95% confidence interval: 82.48% to 88.71%). The model also achieved an image‐wise sensitivity of 81.90%, and a box‐wise sensitivity of 64.60% at a high‐sensitivity operating point. The hard negative mining algorithm significantly boosted both classification (p < .001) and localization (p < .001) performance of the model by reducing false‐positive predictions. Conclusions The deep learning model is promising to detect dental caries on oral photographs captured with consumer cameras. It can be useful for enabling the preliminary and cost‐effective screening of dental caries among large populations.

Bone regeneration is a crucial part in the treatment of periodontal tissue regeneration, in which new attempts come out along with the development of nanomaterials. Herein, the effect of cerium oxide nanoparticles (CeO 2 NPs) on the cell behavior and function of human periodontal ligament stem cells (hPDLSCs) was investigated. Results of CCK-8 and cell cycle tests demonstrated that CeO 2 NPs not only had good biocompatibility, but also promoted cell proliferation. Furthermore, the levels of alkaline phosphatase activity, mineralized nodule formation and expressions of osteogenic genes and proteins demonstrated CeO 2 NPs could promote osteogenesis differentiation of hPDLSCs. Then we chose electrospinning to fabricate fibrous membranes containing CeO 2 NPs. We showed that the composite membranes improved mechanical properties as well as realized release of CeO 2 NPs. We then applied the composite membranes to in vivo study in rat cranial defect models. Micro-CT and histopathological evaluations revealed that nanofibrous membranes with CeO 2 NPs further accelerated new bone formation. Those exciting results demonstrated that CeO 2 NPs and porous membrane contributed to osteogenic ability, and CeO 2 NPs contained electrospun membrane may be a promising candidate material for periodontal bone regeneration.