Search

Freeze–thaw cycles are frequently overlooked as a pivotal factor contributing to leakage and structural failures in clayey soil-impermeable barriers used in landfills or tailings repositories in regions subject to seasonal freezing. This investigation explores the recovery and residual strength properties of Jilin ball clay undergoing six freeze–thaw cycles, and assesses the pore structure characteristics through a series of nuclear magnetic resonance (NMR) tests. The results indicate that normal stress has a greater impact on peak recovery strength than dry density and rest periods. Cohesion increases earlier and more significantly during rest periods compared to internal friction angle. Although the pore diameter remains consistent within the micropores during the freeze–thaw cycles, the soil's structural integrity undergoes notable changes. The concluding analysis provides valuable insights for the construction and management of impermeable barriers in landfills or tailings repositories within seasonally frozen areas. [ABSTRACT FROM AUTHOR]

Alleviating the hypoxia of tumor cells would be an effective strategy to improve the efficiency of sonodynamic therapy (SDT). Here, an Ir(III) phthalocyanine complex (IrPc) is synthesized and characterized, with which a nano‐assembly (IrPc‐NPs) is prepared by encapsulating its aggregates with BSA. IrPc‐NPs exhibit bifunctionality, catalysis on H2O2 decomposition to evolve O2, and sonosensitization to generate 1O2 both in vitro and in vivo. The bifunctionality concertedly and synergistically boosts the efficacy of SDT by alleviating the hypoxia of tumor cells. Its amplifying effect on photoacoustic signal provides a tool to monitor the accumulation of the nano‐assembly in a tumor that guides timely the application of ultrasonic (US) irradiation during SDT treatment. These results also suggest that immunogenic cell death‐mediated immunotherapy for tumor cells is attributed to the efficacy of SDT induced by IrPc‐NPs. IrPc‐NPs exhibit excellent biocompatibility in vitro, benignancy in vivo toward the overall growth of the tumor‐bearing mice inoculated with 4T1 cells and the controllability on timely applying US irradiation during their treatment with IrPc‐NPs renders the nanosystem great potentials in developing into a clinic drug for immunogenic sonodynamic therapy. [ABSTRACT FROM AUTHOR]

Previous research in our laboratory found that the absolute bioavailability of vitexin-2′′- O-rhamnoside (VR) was quite low at 4.89%. A rapid and sensitive UHPLC method using hesperidin as an internal standard was therefore developed and validated to investigate the reasons for this by determining VR in rat plasma after administering intravenously, intraportally (5 mg/kg), intraduodenally and intragastrically (40 mg/kg) to the rat model of the hepatic, gastric and intestinal first-pass effects. As only a high intestinal first-pass effect of VR was found, that is, there existed a low bioavailability of VR (2.40%), inhibitors of P-glycoprotein (P-gp) and cytochrome P450 3A (CYP3A), including verapamil, cyclosporin A and midazolam, and absorption enhancers, including bile salts and borneol, combined with VR, were instilled into duodenum to evaluate the effects on bioavailability of VR. The results demonstrated that area under the concentration-time curve (AUC) values of VR slightly increased after administration of verapamil, cyclosporin A and midazolam, indicating that CYP3A and P-gp do not play an important role in the first-pass effect in the intestine. AUC values of VR significantly increased after administering bile salts or borneol, indicating that the low bioavailability of VR was mainly related to its poor absorption in the intestine. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Hawthorn leaves, a well-known traditional Chinese medicine, have been widely used for treating cardiovascular and fatty liver diseases. The present study aimed to investigate the therapeutic basis treating fatty liver disease by comparing the tissue distribution of six compounds of hawthorn leaf extract (HLE) in fatty liver rats and healthy rats after oral administration at first day, half month and one month, separately. Therefore, a sensitive and specific HPLC method with internal standard was developed and validated to determine chlorogenic acid, vitexin-4′′- O-glucoside, vitexin-2′′- O-rhamnoside, vitexin, rutin and hyperoside in the tissues including heart, liver, spleen, kidney, stomach and intestine. The results indicated that the six compounds in HLE presented some bioactivity in treating rat fatty liver as the concentrations of the six compounds varied significantly in inter- and intragroup comparisons (healthy and/or fatty liver group). Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]