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Abstract Background Acute lung injury (ALI) is a critical inflammatory response syndrome that rapidly develops into acute respiratory distress syndrome (ARDS). Currently, no effective therapeutic modalities are available for patients with ALI/ARDS. According to recent studies, inhibiting both the release of pro-inflammatory cytokines and the formation of reactive oxygen species (ROS) as early as possible may be a promising therapy for ALI. Results In this study, a ROS-responsive nano-delivery system based on oxidation-sensitive chitosan (Ox-CS) was fabricated for the simultaneous delivery of Ce NPs and RT. The in vitro experiments have shown that the Ox-CS/Ceria-Resatorvid nanoparticles (Ox-CS/CeRT NPs) were rapidly and efficiently internalised by inflammatory endothelial cells. Biological evaluations validated the significant attenuation of ROS-induced oxidative stress and cell apoptosis by Ox-CS/CeRT NPs, while maintaining mitochondrial function. Additionally, Ox-CS/CeRT NPs effectively inhibited the release of pro-inflammatory factors. After intraperitoneal (i.p.) administration, Ox-CS/CeRT NPs passively targeted the lungs of LPS-induced inflamed mice and released the drug activated by the high ROS levels in inflammatory tissues. Finally, Ox-CS/CeRT NPs significantly alleviated LPS-induced lung injury through inhibiting both oxidative stress and pro-inflammatory cytokine expression. Conclusions The created Ox-CS/CeRT NPs could act as a prospective nano-delivery system for a combination of anti-inflammatory and anti-oxidant therapy of ALI. Graphical Abstract

Liver fibrosis, a compensatory repair response to chronic liver injury, is caused by various pathogenic factors, and hepatic stellate cell (HSC) activation and phenotypic transformation are regarded as key events in its progression. Ferroptosis, a novel form of programmed cell death, is also closely related to different pathological processes, including those associated with liver diseases. Here, we investigated the effect of doxofylline (DOX), a xanthine derivative with potent anti-inflammatory activity, on liver fibrosis as well as the associated mechanism. Our results indicated that in mice with CCl4-induced liver fibrosis, DOX attenuated hepatocellular injury and the levels of liver fibrosis indicators, inhibited the TGF-β/Smad signaling pathway, and significantly downregulated the expression of HSC activation markers, both in vitro and in vivo. Furthermore, inducing ferroptosis in activated HSCs was found to be critical for its anti-liver fibrosis effect. More importantly, ferroptosis inhibition using the specific inhibitor, deferoxamine (DFO) not only abolished DOX-induced ferroptosis, but also led to resistance to the anti-liver fibrosis effect of DOX in HSCs. In summary, our results showed an association between the protective effect of DOX against liver fibrosis and HSC ferroptosis. Thus, DOX may be a promising anti-hepatic fibrosis agent.

Evaluation of hydrodynamic wave pressure on large-scale structure is an important task in the wave load design of thin-walled components used in sea-crossing bridge. This study focuses on the probability distribution of hydrodynamic wave pressure on a large-scale thin-walled structure using on-site measurement data. An in-situ observation project is conducted to collect the wave elevation and the wave pressure on a rectangle cofferdam during a tropical cyclone event. With the measured data, the wave conditions and the fluctuating wave pressure are extracted, and the corresponding statistical characteristics such as the cumulative density function (CDF) are derived. In addition, a time domain boundary element model (TDBEM) is introduced to provide the statistical comparison. Several wave conditions derived by the statistical wave indicators during the cyclone event are fed to the numerical model for pressure investigation. Based on the statistical indicators and the modeling results, the comparison of wave pressure spatial distribution between TDBEM and the on-site measurement is presented. The pressure probability distribution is presented to further reveal the differences on the statistical characteristics. The resultant bias mainly occurs in the low-exceeding-probability range on the up-wave side and the high-exceeding-probability range on the down-wave side.