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Implant‐related infections (IRIs), characterized by the formation of bacterial biofilms and immunosuppressive microenvironment, are a common but tricky clinical issue. In this study, a self‐adaptive theranostics nanosystem is designed based on phase change material (PCM) for IRIs therapy, which can monitor the severity of infection in real time and automatically provide the most appropriate treatment on demand. The nanosystem called CaAlg/LOD/POD@MNO/FAs (CLPM) is made of the fatty acids (FAs) core with dissolved minocycline (MNO) and the calcium alginate (CaAlg) shell with an immobilized lactate oxidase/pyruvate oxidase (LOD/POD) enzyme‐linked system. When the level of infection is mild (wound temperature < 39 °C), the CLPMs perform a bacteriostatic function by slowly releasing MNO from the solid‐phase FAs core. When the infection deteriorates (wound temperature > 39 °C), the solid‐to‐liquid phase change of FAs not only enables a rapid release of MNO but also disrupts the mechanical strength of the biofilm skeleton doped with CLPM, performing a bactericidal function. In addition, CLPM can reduce the accumulation of bacteria‐derived lactate to address lactate‐induced immunosuppression and enhance immune memory response, thereby inhibiting infection recurrence. [ABSTRACT FROM AUTHOR]

Bacteria-derived hydrogen sulfide (H 2 S) often contributes to the emergence of antibiotic-recalcitrant bacteria, especially persister (a sub-population of dormant bacteria), thus causing the treatment failure of Catheter-associated urinary tract infection (CAUTI). Here, an H 2 S harvester nanosystem to prevent the generation of persister bacteria and disrupt the dense biofilm matrix by the self-adaptive ability of shape-morphing is prepared. The nanosystem possesses a core-shell structure that is composed of liquid metal nanoparticle (LM NP), AgNPs, and immobilized urease. The nanosystem decomposes urea contained in urine to generate ammonia for eliminating bacteria-derived H 2 S. Depending on the oxidative layer of liquid metal, the nanosystem also constitutes a long-lasting reservoir for temporarily storing bacteria-derived H 2 S, when urease transiently overloads or in the absence of urine in a catheter. Depriving H 2 S can prevent the emergence of persistent bacteria, enhancing the bacteria-killing efficiency of Ga 3+ and Ag + ions. Even when the biofilm has formed, the urine flow provides heat to trigger shape morphing of the LM NP, tearing the biofilm matrix. Collectively, this strategy can turn trash (urea) into treasure (H 2 S scavengers and biofilm rippers), and provides a new direction for the antibacterial materials application in the medical field., (© 2024 Wiley‐VCH GmbH.)

Microbial structural changes and dysfunction play an important role in the development of cerebral ischemia. We searched PubMed, Embase, Web of Science, and Cochrane Library and conducted a systematic review to assess the relationship between the human microbiome and ischemic stroke. A total of 24 studies were included, and the intestinal bacterial communities detected in both stroke and healthy people were dominated by 4 main phyla, including Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria. Significant diversity (alpha and beta) in patients with ischemic versus nonischemic stroke was observed in nine out of 18 studies, and 3 studies showed that the severity of ischemic stroke affected microbial diversity. The imbalance of bacteria that produce short-chain fatty acids (SCFAs) changes the bacterial metabolic pathway, and disorders in the level of bacterial metabolites (trimethylamine N-oxide TMAO) lead to significant changes in intestinal flora function, which may aggravate the severity of stroke and affect its prognosis. Further studies are needed to explore the relationship between the microbiome and ischemic stroke., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)