The emergence of multidrug resistant bacteria has resulted in plenty of stubborn nosocomial infections and severely threatens human health. Developing novel bactericide and therapeutic strategy is urgently needed. Herein, mesoporous silica supported silver–bismuth nanoparticles (Ag‐Bi@SiO2 NPs) are constructed for synergistic antibacterial therapy. In vitro experiments indicate that the hyperthermia originating from Bi NPs can disrupt cell integrity and accelerate the Ag ions release, further exhibiting an excellent antibacterial performance toward methicillin‐resistant Staphylococcus aureus (MRSA). Besides, under laser irradiation, Ag‐Bi@SiO2 NPs at 100 µg mL−1 can effectively obliterate mature MRSA biofilm and cause a 69.5% decrease in the biomass, showing a better therapeutic effect than Bi@SiO2 NPs with laser (26.8%) or Ag‐Bi@SiO2 NPs without laser treatment (30.8%) groups. More importantly, in vivo results confirm that ≈95.4% of bacteria in abscess are killed and the abscess ablation is accelerated using the Ag‐Bi@SiO2 NPs antibacterial platform. Therefore, Ag‐Bi@SiO2 NPs with photothermal‐enhanced antibacterial activity are a potential nano‐antibacterial agent for the treatment of skin infections.

Phase change material based H2O2 self-supply nanoparticles for enhanced thermal responsive chemodynamic tumor therapy.

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Necroptosis has been discovered as a new paradigm of cell death and may play a key role in heart disease and selenium (Se) deficiency. Hence, we detected the specific microRNA (miRNA) in response to Se-deficient heart using microRNAome analysis. For high-throughput sequencing using Se-deficient chicken cardiac tissue, we selected miR-200a-5p and its target gene ring finger protein 11 (RNF11) based on differential expression in cardiac tissue and confirmed the relationship between miR-200a-5p and RNF11 by dual luciferase reporter assay and real-time quantitative PCR (qRT-PCR) in cardiomyocytes. We further explored the function of miR-200a-5p and observed that overexpression of miR-200a-5p spark the receptor interacting serine/threonine kinase 3 (RIP3)-dependent necroptosis in vivo and in vitro. To understand whether miR-200a-5p and RNF11 are involved in the RIP3-dependent necroptosis pathway, we presumed that oxidative stress, inflammation response and the mitogen-activated protein kinase (MAPK) pathway might trigger necroptosis. Interestingly, necroptosis trigger, z-VAD-fmk, failed to induce necroptosis but enhanced cell survival against necrosis in cardiomyocytes with knockdown of miR-200a-5p. Our present study provides a new insight that the modulation of miR-200a-5p and its target gene might block necroptosis in the heart, revealing a novel myocardial necrosis regulation model in heart disease.

Recent advances in cancer chemodynamic therapy based on Fenton chemistry are reviewed, including the working mechanism, characteristics, and strategies for optimizing treatment efficiency.

The combination of reactive oxygen species‐involved chemodynamic therapy (CDT) and photothermal therapy (PTT) holds great promise in enhancing anticancer effects. Herein, a multifunctional Fe‐doped polyoxometalate (Fe‐POM) cluster is fabricated via a simple method. The Fe‐POM can not only be utilized as PTT agents to generate a hyperthermia effect for cancer cell killing under near‐infrared (NIR) II laser (1060 nm) irradiation, but also can be used as CDT agents to convert endogenous less‐reactive H2O2 into harmful ·OH and simultaneously deplete glutathione for an amplified CDT effect. Notably, the hyperthermia induced by PTT can further enhance the CDT effect, achieving a synergistic PTT/CDT effect. Owing to the self‐assembling properties at lowered pH values, the Fe‐POM exhibits high tumor accumulation as revealed by photoacoustic imaging. More importantly, Fe‐POM enables effective destruction of tumors without inducing noticeable damage to normal tissues under 1060 nm laser irradiation. The work presents a new type of multifunctional agent with high PTT/CDT efficacy, providing promising methods for PTT‐enhanced CDT in a NIR‐II biowindow.

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The current feasibility of nanocatalysts in clinical anti-infection therapy, especially for drug-resistant bacteria infection is extremely restrained because of the insufficient reactive oxygen generation. Herein, a novel Ag/Bi2MoO6 (Ag/BMO) nanozyme optimized by charge separation engineering with photoactivated sustainable peroxidase-mimicking activities and NIR-II photodynamic performance was synthesized by solvothermal reaction and photoreduction. The Ag/BMO nanozyme held satisfactory bactericidal performance against methicillin-resistant Staphylococcus aureus (MRSA) (~99.9%). The excellent antibacterial performance of Ag/BMO NPs was ascribed to the corporation of peroxidase-like activity, NIR-II photodynamic behavior, and acidity-enhanced release of Ag+. As revealed by theoretical calculations, the introduction of Ag to BMO made it easier to separate photo-triggered electron-hole pairs for ROS production. And the conduction and valence band potentials of Ag/BMO NPs were favorable for the reduction of O2 to ·O2−. Under 1064 nm laser irradiation, the electron transfer to BMO was beneficial to the reversible change of Mo5+/Mo6+, further improving the peroxidase-like catalytic activity and NIR-II photodynamic performance based on the Russell mechanism. In vivo, the Ag/BMO NPs exhibited promising therapeutic effects towards MRSA-infected wounds. This study enriches the nanozyme research and proves that nanozymes can be rationally optimized by charge separation engineering strategy.