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[Display omitted] • Neutrophil accumulation raises defence against Streptococcus equi ssp. zooepidemicus in the absence of GSDMD; • GSDMD deficiency promoted the release of CXCL1 and CXCL2 mediated by p65 phosphorylation; • GSDMD deficiency activated NF-κB pathway in neutrophil to release cytokines against SEZ. Streptococcus equi ssp. zooepidemicus (SEZ) predominantly acts as a zoonotic pathogen, capable of infecting a diverse range of animal species including human. Gasdermin D (GSDMD) exhibited comprehensive functions in host against different pathogenic microorganism. This study aimed to investigate the role of GSDMD in host against SEZ. Mice were administrated with SEZ via intranasal intubation for 24 h (3 × 106CFU), GSDMD protein expression significantly increased in the lung tissue of mice infected with SEZ. For further research on the role of GSDMD during SEZ infection, GSDMD-/- mice and WT mice were treated with SEZ via intranasal intubation for 24 h (3 × 106CFU). GSDMD-/- mice showed less severe lung tissue due to fewer bacteria colonization. Numerous neutrophils were recruited into lung tissues in GSDMD-/- mice, related to the release of CXCL1 and CXCL2 regulated by p65 phosphorylation. In further study, neutrophils of WT and GSDMD-/- mice were isolated and treated with SEZ (multiplicity of infection, MOI = 10, 4 h). The absence of GSDMD alleviated the death of neutrophils, in addition, GSDMD deficiency could promote translocation of p65 from the cytoplasm into the nucleus in neutrophil, which may contribute to the release of IL-1β and TNF-α. This study demonstrated a novel function of GSDMD in host immune response to SEZ invading, indicating that GSDMD deficiency ameliorated SEZ infection through enhancing neutrophil accumulation into infected site, and activating NF-κB pathway in neutrophil to release cytokines against SEZ. Our study suggested that inhibition of host GSDMD may be an effective method against SEZ. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using self-assembly and in-situ reduction strategy, the stable Pt nanoblocks were simply synthesized. • The growth of the rGO/(PLL/PASP) n -PtNB nanocomposites can be controlled by adjusting the concentrations of K 2 PtCl 6 solution, the bilayers number and concentrations of the rGO/(PLL/PASP) n nanofilms.. • The rGO/(PLL/PASP) 3 -PtNB nanocomposites can efficiently transform 4-nitrophenol into 4-aminophenol completely within 4.5 min (k app is 0.962 min−1) and keep good long-term stability. To develop Pt nanomaterials with facile approach is of great significance for the improvement of their catalytic properties for organic pollutants degradation. In this study, we report a simple in-situ reduction strategy to prepare Pt nanoblocks based on graphene/ polyamino acid self-assembly nanofilms. Polyamino acid modified graphene nanofilms severed as the nanoreactor and reducing agent for further fabrication of Pt nanoblocks. The as-prepared complex efficiently transformed 4-nitrophenol into 4-aminophenol completely within 4.5 min (k app is 0.962 min−1) and kept good long-term stability. We expect this work to offer a new valuable insight for facile preparation of Pt materials as efficient and recyclable catalysts for water pollution remediation. [ABSTRACT FROM AUTHOR]

Streptococcus equi ssp. zooepidemicus (S. zooepidemicus, SEZ) is a zoonotic bacterial pathogen that can cause various inflammation, including pneumonia. As the most abundant leukocytes in the circulation, neutrophils are the first wave of leukocytes to arrive in the lung upon infection. This study aims to evaluate the effect of caspase-1 on the host response to SEZ infection in a mouse model. Intranasal exposure to SEZ induced the expression of caspase-1 in wild-type mice lung, and increased the number of neutrophils in the alveolar cavity and alveolar wall. In addition, caspase-1 deficiency reduced the transcription levels of IL-1α, IL-1β, IL-6, and TNF-α in the lungs of infected mice, which was accompanied by decreased recruitment of pulmonary neutrophils. Moreover, knocking out caspase-1 decreased the bactericidal activity of neutrophils and promoted the pulmonary bacterial load. In line with this, the mortality of caspase-1−/− mice infected with SEZ was significantly increased compared with those of caspase-1+/+ mice. Collectively, recruiting neutrophils and enhancing the bactericidal ability of neutrophils are important means for caspase-1 to promote bacterial clearance. • SEZ exposure induces caspase-1 activation and neutrophil recruitment. • Caspase-1 deficiency impairs neutrophil recruitment and bacterial clearance. • Caspase-1 affects the transcription of pulmonary inflammatory factors during SEZ infection. • Caspase-1 was demonstrated to play an indispensable role in mice against SEZ infection. [ABSTRACT FROM AUTHOR]

Drug repurposing is considered a promising strategy to fight antimicrobial resistance (AMR). Methotrexate (Mtx), a classical anticancer drug, could strongly inhibit bacterial dihydrofolate reductase (DHFR). However, its poor permeability into bacteria and potent human cytotoxicity make it unsuitable as an antibacterial. Herein, we reported the conjugation of Mtx with a siderophore to construct "Trojan horse" antibacterials. The most potent conjugate 8 with nanomolar minimum inhibitory concentration (MIC) values exhibited over 1.00×103‐fold improved activity against Gram‐positive Streptococcus pneumoniae (S. pneumoniae) and Gram‐negative Yersinia enterocolitica (Y. enterocolitica) compared with Mtx, while possessing 2.31×103‐fold reduced human cytotoxicity, resulting in 2.08×106‐fold improvements in the therapeutic index. This proof‐of‐principle study verifies that siderophore conjugation is an effective strategy for developing new antibacterials from anticancer drugs. [ABSTRACT FROM AUTHOR]

Drug repurposing is considered a promising strategy to fight antimicrobial resistance (AMR). Methotrexate (Mtx), a classical anticancer drug, could strongly inhibit bacterial dihydrofolate reductase (DHFR). However, its poor permeability into bacteria and potent human cytotoxicity make it unsuitable as an antibacterial. Herein, we reported the conjugation of Mtx with a siderophore to construct "Trojan horse" antibacterials. The most potent conjugate 8 with nanomolar minimum inhibitory concentration (MIC) values exhibited over 1.00×103‐fold improved activity against Gram‐positive Streptococcus pneumoniae (S. pneumoniae) and Gram‐negative Yersinia enterocolitica (Y. enterocolitica) compared with Mtx, while possessing 2.31×103‐fold reduced human cytotoxicity, resulting in 2.08×106‐fold improvements in the therapeutic index. This proof‐of‐principle study verifies that siderophore conjugation is an effective strategy for developing new antibacterials from anticancer drugs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Improving the bond energy of TM O bonds (especially that of Mn O bonds) and suppresses the formation of O O bonds. • Delaying the P2-O2 phase transition voltage from 4.2 to 4.4 V. • The Na 0.67 Ni 0.23 Cu 0.1 Mn 0.67 O 2 cathode retained specific capacity of 69.4 mAh/g (2C) even after 500 cycles. P2-type Na 0.67 Ni 0.33 Mn 0.67 O 2 has attracted considerable attraction as a cathode material for sodium-ion batteries owing to its high operating voltage and theoretical specific capacity. However, when the charging voltage is higher than 4.2 V, the Na 0.67 Ni 0.33 Mn 0.67 O 2 cathode undergoes a detrimental irreversible phase transition of P2-O2, leading to a drastic decrease in specific capacity. To address this challenge, we implemented a Cu-doping strategy (Na 0.67 Ni 0.23 Cu 0.1 Mn 0.67 O 2) in this work to stabilize the structure of the transition metal layer. The stabilization strategy involved reinforcing the transition metal–oxygen (TM O) bonds, particularly the Mn O bond and inhibiting interlayer slip during deep desodiation. As a result, the irreversible phase transition voltage is delayed, with the threshold voltage increasing from 4.2 to 4.4 V. Ex-situ X-ray diffraction measurements revealed that the Na 0.67 Ni 0.23 Cu 0.1 Mn 0.67 O 2 cathode maintains the P2 phase within the voltage window of 2.5–4.3 V, whereas the P2-Na 0.67 Ni 0.33 Mn 0.67 O 2 cathode transforms entirely into O2-type Na 0.67 Ni 0.33 Mn 0.67 O 2 when the voltage exceeds 4.3 V. Furthermore, absolute P2-O2 phase transition of the Na 0.67 Ni 0.23 Cu 0.1 Mn 0.67 O 2 cathode occurred at 4.6 V, indicating that Cu2+ doping enhances the stability of the layer structure and increases the threshold voltage. The resulting Na 0.67 Ni 0.23 Cu 0.1 Mn 0.67 O 2 cathode exhibited superior electrochemical properties, demonstrating an initial reversible specific capacity of 89.1 mAh/g at a rate of 2C (360 mA g−1) and retaining more than 78 % of its capacity after 500 cycles. [ABSTRACT FROM AUTHOR]

Transition metal selenides are regarded as one of the most promising anode materials because of their high theoretical specific capacity and large layer spacing. However, the unstable structural behavior and slow reaction kinetics during electrochemical reactions seriously hinder its application. Herein, a novel nanocomposite structure of WSe 2 /CoSe 2 nanocrystals vertically grown on carbon nanofibers (WSe 2 /CoSe 2 /CNFs) was developed as anode material by electrospinning and heat treatment. In which, the self-supporting structures formed by the intersecting carbon nanofibers effectively alleviate severe volume expansion during sodiation/desodiation process, thus ensuring excellent stability. And the highly exposed CoSe 2 /WSe 2 grown on the surface of carbon nanofibers provide abundant reaction interfaces and fast ion diffusion channels. As expected, the WSe 2 /CoSe 2 /CNFs anode shows excellent electrochemical performance, including high capacity (403.5 mAh g−1 at 0.2 A g−1), long-term cycling stability (333.5 mAh g−1 after 1800 cycles at 5 A g−1 with negligible capacity decay per cycle of only 0.0012 %) and remarkable rate performance (a reversible capacity of 312.6 mAh g−1 is achieved even at a high current density of 20 A g−1). Meanwhile, the excellent sodium storage performance of the WSe 2 /CoSe 2 /CNFs composites electrode was deeply investigated by kinetic analysis. [Display omitted] • Developed three-dimensional WSe 2 /CoSe 2 /CNFs nanocomposites with hierarchical heterostructures. • It was prepared by facile electrospinning method and selenization process. • WSe 2 /CoSe 2 /CNFs anode exhibits long cycle stability at high current density and excellent rate performance. • High performance benefits from the unique heterostructures and the synergistic effect of bimetallic selenium. [ABSTRACT FROM AUTHOR]

• Using assembly and in-situ reduction strategy, a SERS substrate were synthesized. • The composites show high adsorption for both hydrophobic and hydrophilic molecules. • The composites exhibit remarkable SERS detection and reproducibility for thiram and methylene blue with the limitation of 10−9 M and 10−15 M, respectively. Surface-enhanced Raman scattering (SERS) spectroscopy is a highly sensitive and nondestructive method to detect a wide range of probe molecules in the field of agriculture and industry. However, to prepare a homogeneous and reproducible SERS substrate is still a great challenge. Herein, we propose a facile strategy to prepare a homogeneous SERS substrate that presents remarkable adsorption and reproducibility by using electrostatic assembly and in-situ reduction technology. The reduced graphene oxide assembled films modified with polyelectrolytes and heptakis (6-deoxy-6-amino)-β-cyclodextrin are used as the template and reducing agent in the preparation process. By means of simply mixing with AgNO 3 solution, composites containing Ag nanoparticles were obtained. The as-prepared composites present great stability and remarkable adsorption for both hydrophobic and hydrophilic molecules, such as thiram and methylene blue. Combined the functions of reduced graphene, polyelectrolytes and β-cyclodextrin components, the composites exhibit highly sensitive SERS signals with inhibiting the influence of fluorescence. The detection limit of thiram and methylene blue are 10−9 M and 10−15 M, respectively. Furthermore, the composites serve as a reproducible SERS substrate to overcome randomness of SERS results and improve reproducibility. We expect this study to provide a novel method to fabricate more effective SERS substrates. [ABSTRACT FROM AUTHOR]