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Extracellular vesicles (EVs) derived from differentiating induced stem cells maintain their original stemness and differentiating trends and possess strong immunoregulatory capability. Biomaterials equipped with EVs are very promising in regenerative medicine. However, surface EV‐decoration on osteoimplants remains a challenge, due to the complexity of traditional molecular conjugations and the fragility of EVs. Here, mussel‐like molecular adhesion is combined with bioorthogonal click conjugation to introduce EVs on titanium (Ti) implants. The biomimetic adhesion and clickable molecular linkage allow mild and stable tethering of pre‐osteogenic mesenchymal stem cell (MSC)‐derived EVs on Ti implants. EV‐decorated implants exhibit significantly enhanced osseointegration on the bone‐implant surface under diabetic conditions, promoting increased expression of osteogenic genes. Modified surfaces impelled phenotypic alterations in macrophage polarization via multi‐pathway regulation, decreasing proinflammatory M1 macrophage formation, which can lead to the promotion of surface osteogenesis. On Ti rods implanted in a diabetic rat model, EV coating inhibited M1macrophages around the prosthesis, resulting in satisfactory long‐term osseointegration. This study offers a new perspective to represent a simple and effective means for surface EV decoration, providing an osteoimmunomodulatory effect to enhance the diabetic osseointegration of implants. [ABSTRACT FROM AUTHOR]

Recurrent bacterial infections, impenetrable microbial biofilms, and irremediable antibiotic resistance are the most perilous threats in orthopedic implant‐associated infections (IAIs). Recently, chemodynamic therapy (CDT) has been considered a promising therapy, while the clinical practices for existing CDT agents are limited by the low therapeutic efficiency in physiological circumstances. Herein, it is demonstrated that silica‐copper nanosheets (Si@Cu NSs) exhibit a combined therapeutic photothermal‐chemodynamic strategy for IAIs treatment with superior capacity and biocompatibility. This unique design endows the nanostructure with enhanced copper‐based Fenton‐like properties via p‐d orbital hybridization by incorporating copper nanoclusters (Cu NCs) on silicene nanosheets (Si NSs) matrix, integrating inherent photothermal performance of Si NSs with specific catalytic anti‐infection of Cu NCs against planktonic bacteria and biofilms both in vitro and in vivo. This study not only reveals the promising bio‐application prospects of 2D nanocatalytic biomaterials but also demonstrates the feasibility of constructing novel CDT agents by orbital hybridization for the catalytic treatment of IAIs. [ABSTRACT FROM AUTHOR]

Robust bacterial metabolism and the immunosuppression on peripheral immune cells cause biofilm‐associated infections (BAIs) extremely refractory to be eradicated via antibiotics alone. Herein, hierarchical mesoporous UiO‐66 metal–organic framework is decorated with selenite, polypyrrole, and macrophage membrane (MM) to develop a biomimetic nanosphere (USPM). Following the recruitment of USPM to the biofilm microenvironment (BME) via the pathogen‐targeting ability derived from MM. The BME‐responsive USPM can precisely release selenite to penetrate the loosened biofilm in synergy with near‐infrared‐induced mild photothermal therapy (mPTT). Selenite can quickly react with reducing substances to generate hydrogen selenide (H2Se) inside the biofilm. H2Se can competitively inhibit bacterial metabolic processes and disrupt biofilm metabolic homeostasis by cascade amplification effects. Furthermore, H2Se inside the biofilm further sensitizes photothermia to exert a precise local photothermal effect. Outside the biofilm, USPM can simultaneously promote the phagocytosis and autophagy of macrophages to kill and decompose the phagocytosed bacteria. Finally, the well‐decomposed bacterial antigens in macrophages can be presented to antigen‐presenting cells to arouse adaptive immune responses and enhance anti‐biofilm effectiveness further. Such powerful mPTT‐enhanced bacterial metabolic disruption and macrophagic autophagy‐promoted adaptive immune activation suggest an alternative therapeutic strategy to cure refractory BAIs. [ABSTRACT FROM AUTHOR]

Li+/Na+ exchange has been extensively explored as an effective method to prepare high‐performance Mn‐based layered cathodes for Li‐ion batteries, since the first report in 1996 by P. G. Bruce (Nature, 1996. 381, 499–500). Understanding the detailed structural changes during the ion‐exchange process is crucial to implement the synthetic control of high‐performance layered Mn‐based cathodes, but less studied. Herein, in situ synchrotron X‐ray diffraction, density functional theory calculations, and electrochemical tests are combined to conduct the systemic studies into the structural changes during the ion‐exchange process of an Mn‐only layered cathode O3‐type Li0.67[Li0.22Mn0.78]O2 (LLMO) from the corresponding counterpart P3‐type Na0.67[Li0.22Mn0.78]O2 (NLMO). The temperature‐resolved observations combined with theoretical calculations reveal that the Li+/Na+ exchange is favorable thermodynamically and composited with two tandem topotactic phase transitions: 1) from NLMO to a layered intermediate through ≈60% of Li+/Na+ exchange. 2) then to the final layered product LLMO through further Li insertion. Moreover, the intermediate‐dominate composite is obtained by slowing down the exchange kinetics below room temperature, showing better electrochemical performance than LLMO obtained by the traditional molten‐salt method. The findings provide guides for the synthetic control of high‐performance Mn‐based cathodes under mild conditions. [ABSTRACT FROM AUTHOR]

Biofilm-infected diabetic wounds (BIDWs) with hyperglycemia and bacterial colonization are characterized by disordered inflammation and abnormal activation ofNLRP3 inflammasome, leading to sustained macrophage M1 polarization and neutrophil extracellular traps (NETs) formation. An immoderate anti-inflammatory treatment that downregulates NLRP3 in turn promotes the persistence of biofilm infections and impairs the healing ofBIDWs. Therefore, reconciling biofilm elimination and immune regulation holds the promise of curing BIDWs. Herein, a novel spatiotemporal on-off immunomodulatory therapy (SOIT) is proposed for treating BIDWs through biphasic regulation of NLRP3. Methacrylate gelatin hydrogels (Gel-MA) incorporated with graphene oxide (GO) and metformin-loaded mesoporous silicone nanospheres are synthesized and photo cross-linked to construct a nanocomposite hydrogel (MGO@GM). First, GO nanosheets released from MGO@GM inhibit bacterial biofilm formation and disrupt mature biofilms under near-infrared irradiation. Meanwhile, GO activates the NLRP3 to induce a macrophage-associated proinflammatory response against biofilms. Afterward, with the subsequent degradation ofMGO@GM, released metformin reduces local hyperglycemia, downregulates NLRP3, and inhibits NETs formation. Furthermore, repolarized M2 macrophages alleviate the inflammatory microenvironment and promote tissue regeneration. Briefly, this SOIT strategy regulates the NLRP3 and rescues impaired innate immunity to facilitate anti-infection and tissue repair, which provides a new perspective for the future clinical treatment of BIDWs. [ABSTRACT FROM AUTHOR]

Conformal integration of electronics on complex curvilinear surfaces remains challenging, especially for those devices made of non‐stretchable materials. Transforming as‐fabricated planar sheets onto curved surfaces requires the materials to be flexible and stretchable, which is intrinsically in conflict with the nature of non‐stretchable materials. Here, a novel assembly strategy for conformal electronics is proposed that utilizes kirigami design at the structural level for the non‐stretchable planar sheets to conformally and completely wrap the curved surfaces, and employs self‐healing materials to connect the sheets at the seams. Conductive self‐healing materials are used to ensure the electrical conductivity of the functional materials so as to assure device functionality. The transformation from a planar kirigami sheet to a sphere surface demonstrates this strategy, which is designed and predicted by theoretical and numerical studies and realized by experiments. Simple examples such as a conformal heater and a multifunctional wind sensing system on a spherical surface demonstrate the wide potential applications of the proposed strategy. [ABSTRACT FROM AUTHOR]