Health risk assessment for soil radioactivity around Shidaowan nuclear power plant in Shandong, China.

Monitoring radioactivity levels in the environment around nuclear power plants is of great significance to assessing environmental safety and impact. Shidaowan nuclear power plant is currently undergoing commissioning; however, the baseline soil radioactivity is unknown. The naturally occurring radionuclides 238U, 232Th, 226Ra and 40K, and artificial radionuclide (AR) 137Cs in soil samples around the Shidaowan nuclear power plant were measured to establish the baseline levels. Human health hazard indices such as external hazard indices (Hex), Radium equivalent (Raeq), outdoor absorbed dose rate (Dout), annual effective dose (AED) and excess lifetime cancer risk (ELCR) were estimated. The average concentration of 232Th, 40K, 137Cs, 238U and 226Ra were 42.6 ± 15, 581 ± 131, 0.68 ± 0.38, 40.13 ± 9.07 and 40.8 ± 12.8 Bq per kg, respectively. The average Hex, Raeq, Dout, AED and ELCR were 0.40, 146 Bq per kg, 68.8 nGy per h, 0.09 mSv per y and 3.29E-04, respectively. These data showed an acceptable level of risk to residents near the nuclear power plant and that the current radioactivity in the soil may not pose immediate harm to residents living close to the nuclear power plant. The observed lower AED and 40 K and 137Cs concentrations were comparable to other studies, whilst ELCR was higher than the world average of 2.9E-04. The commissioning of the Shidaowan nuclear power plant is potentially safe for the surrounding residents; further continuous monitoring is recommended.

Andrographolide protects against atrial fibrillation by alleviating oxidative stress injury and promoting impaired mitochondrial bioenergetics. / ç©¿å¿ƒèŽ²å† é ¯é€šè¿‡ç¼“è§£æ°§åŒ–åº”æ¿€å’Œä¿ƒè¿›çº¿ç²’ä½“èƒ½é‡åˆæˆå¯¹å¿ƒæˆ¿é¢¤åŠ¨å‘æŒ¥é¢„é˜²ä½œç”¨.

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia seen in clinical settings, which has been associated with substantial rates of mortality and morbidity. However, clinically available drugs have limited efficacy and adverse effects. We aimed to investigate the mechanisms of action of andrographolide (Andr) with respect to AF. We used network pharmacology approaches to investigate the possible therapeutic effect of Andr. To define the role of Andr in AF, HL-1 cells were pro-treated with Andr for 1 h before rapid electronic stimulation (RES) and rabbits were pro-treated for 1 d before rapid atrial pacing (RAP). Apoptosis, myofibril degradation, oxidative stress, and inflammation were determined. RNA sequencing (RNA-seq) was performed to investigate the relevant mechanism. Andr treatment attenuated RAP-induced atrial electrophysiological changes, inflammation, oxidative damage, and apoptosis both in vivo and in vitro. RNA-seq indicated that oxidative phosphorylation played an important role. Transmission electron microscopy and adenosine triphosphate (ATP) content assay respectively validated the morphological and functional changes in mitochondria. The translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) to the nucleus and the molecular docking suggested that Andr might exert a therapeutic effect by influencing the Keap1-Nrf2 complex. In conclusions, this study revealed that Andr is a potential preventive therapeutic drug toward AF via activating the translocation of Nrf2 to the nucleus and the upregulation of heme oxygenase-1 (HO-1) to promote mitochondrial bioenergetics.

Photothermal/lysozyme-catalyzed hydrolysis dual-modality therapy via halloysite nanotube-based platform for effective bacterial eradication.

Bacterial biofilm seriously impedes the healing of infected wound, remaining a major challenge in wound repair. Antibiotic-free antibacterial strategies based on nanotechnology are emerging as promising tools to combat bacterial infections. Here, halloysite nanotube (HNT), as a natural clay mineral, was employed to fabricate a multifunctional platform (designated as HNTs@CuS@PDA-Lys) through a layer-by-layer strategy for treating bacterial infections by utilizing synergistic lysozyme (Lys)-photothermal therapy (PTT). Specifically, amino-modified HNTs were first decorated with copper sulfide (CuS), followed by coated with a polydopamine (PDA) layer, then functionalized with antimicrobial enzyme Lys onto the surface of PDA via cation-π interactions. The as-prepared HNTs@CuS@PDA-Lys at a low dose (200 µg/mL) exhibited excellent synergistic Lys-photothermal bactericidal activity against Escherichia coli (E. coli) (100.0 ± 0.2 %) and Staphyloccocus aureus (S. aureus) (99.9 ± 0.1 %), eliminated 75.9 ± 2.0 % of S. aureus biofilm under near-infrared (NIR) irradiation (808 nm, 1.5 W/cm2). In vivo experiments using a S. aureus-infected rat model showed HNTs@CuS@PDA-Lys could rapidly kill bacteria and accelerate wound healing process. Overall, this multifunctional nanoplatform combines the advantages of PTT and Lys, providing a cost-efficient, environmental friendly strategy for bacterial and biofilm eradication, demonstrating the potential applications in the field of biomedicine.

Porous Se@SiO2 nanospheres attenuate ischemia/reperfusion (I/R)-induced acute kidney injury (AKI) and inflammation by antioxidative stress.

OBJECTIVES: Acute kidney injury (AKI) is a growing global health concern, and is associated with high rates of mortality and morbidity in intensive care units. Se is a trace element with antioxidant properties. This study aimed to determine whether porous Se@SiO2 nanospheres could relieve oxidative stress and inflammation in ischemia/reperfusion (I/R)-induced AKI. METHODS: Male 6- to 8-week-old C57bl/6 mice were divided into four groups: sham + saline, sham + Se@SiO2, I/R + saline, and I/R + Se@SiO2. Mice in the I/R groups experienced 30 minutes of bilateral renal I/R to induce an AKI. Porous Se@SiO2 nanospheres (1 mg/kg) were intraperitoneally injected into mice in the I/R + Se@SiO2 group 2 hours before I/R, and the same dose was injected every 12 hours thereafter. Hypoxia/reoxygenation (H/R) was used to mimic I/R in vitro. PBS was used as a control treatment. Human kidney 2 cells were seeded into 12-well plates (5×105 cells/well) and divided into four groups: control + PBS group, control + Se@SiO2 group, H/R + PBS group, and H/R + Se@SiO2 group (n=3 wells). We then determined the expression levels of ROS, glutathione, inflammatory cytokines and proteins, fibrosis proteins, and carried out histological analysis upon kidney tissues. RESULTS: In vitro, intervention with porous Se@SiO2 nanospheres significantly reduced levels of ROS (P<0.05), inflammatory cytokines (P<0.05), and inflammation-associated proteins (P<0.05). In vivo, tubular damage, cell apoptosis, and interstitial inflammation during AKI were reduced significantly following treatment with porous Se@SiO2 nanospheres. Moreover, the occurrence of fibrosis and tubular atrophy after AKI was attenuated by porous Se@SiO2 nanospheres. CONCLUSION: Porous Se@SiO2 nanospheres exhibited a protective effect in I/R-induced AKI by resisting oxidative stress and inflammation. This suggests that porous Se@SiO2 nanospheres may represent a new therapeutic method for AKI.