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Carboxymethyl chitosan (CMCS), as a water‐soluble, biocompatible, and biodegradable polymer, is an excellent carrier for a sustained drug delivery system. In this study, a amphiphilic carboxymethyl chitosan‐ursolic acid nano‐drug carrier modified by folic acid (FPCU) were prepared, and then the nano‐drug carrier wrapped another anticancer drug 10‐hydroxycamptothecin were self‐assembled into nanoparticles (FPCU/HCPT NPs). The FPCU/HCPT NPs had a suitable size, high drug loading efficiency of ursolic acid (6.4%) and 10‐hydroxycamptothecin (14.1%). The drug release study in vitro indicated that the nanoparticles have obviously sustained effect and pH sensitive behaviors, the drug release amount was higher at pH 5.5 than at pH 7.4. in vitro and in vivo study showed that the nanoparticles displayed a high antitumor efficiency to tumor cells compared with free drug. The nano delivery system as a carrier for ursolic acid (UA) and 10‐hydroxycamptothecin (HCPT) has good application prospects in cancer treatment. [ABSTRACT FROM AUTHOR]

2 9 Si Nuclear Magnetic Resonance (NMR) can measure the molecular structure of silicate in oilfield reinjection water. However, noise in 2 9 Si NMR spectra (NMRS) affects the determination of silicate molecular structure type. To solve this problem, a new peak fitting method (Two-step Greedy-Singular Spectrum Analysis-Gaussian Fitting Method, TSG-SSA-GFM) is proposed in this paper. This method first uses TSG to determine the embedding dimension, then uses SSA to determine the characteristic peak position. Finally, GFM is used to calculate the molar ratio of characteristic peaks. The results show that TSG can quickly determine the embedding dimension and reduce computation by at least 50% vs. the global ergodic method. The mean deviation of characteristic peak positions determined by SSA is 0.07 ppm, while Discrete Wavelet Transform (DWT) and Empirical Mode Decomposition (EMD) cannot determine characteristic peaks of 2 9 Si NMRS containing overlapping peak. The average R -squared of Gaussian fitting of 2 9 Si NMRS is 98.4% while Lorentzian is 90.6%. Therefore, this study provides an important method for quantitative analysis of 2 9 Si NMRS. [ABSTRACT FROM AUTHOR]

Precise ions sieving at angstrom-scale is gaining tremendous attention thanks to its significant impact at the water-energy nexus. Herein, a novel polycation-modulated interfacial polymerization (IP) strategy is developed to prepare a heterogeneously charged covalent organic frameworks (COFs) membrane. Cationic poly(diallyldimethylammonium chloride) (PDDA) regulates the growth and assembly of anionic COFs nanosheets, which thus provides a negative, smooth top surface and positive, rough bottom surface, indicating the presence of heterogeneously charged angstrom-scale channels through the membrane. Experiments and simulations are conducted to understand the facilitated ions transport behavior relative to specific interactions raised by heterogeneously charged channels and angstrom-scale steric hinderance as well, rendering the membrane with robust mono-/divalent cations sieving capabilities. The selectivity (61.6) of Li + to Mg 2+ in mixed saline under the continuous cross-flow filtration mode is superior to most of the reported nanofiltration membranes. This polycation-mediated interfacial polymerization strategy offers a compelling opportunity to develop versatile heterogeneously charged COF membranes for exquisite ion sieving., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Solid polymer electrolytes (SPEs) have garnered extensive attention as potential alternatives to traditional liquid electrolytes, primarily due to their prowess in curbing lithium dendrite formation and preventing electrolyte leaks. The quest for SPEs that are both mechanically robust and exhibit superior ionic conductivity has been vigorous. However, achieving a harmonious balance between these two attributes remains a significant challenge. In this study, we introduce a novel quasi-solid electrolyte, ingeniously crafted from a poly(urethane-urea) network, enriched with lithium salts and plasticizers. This innovative composition not only boasts remarkable toughness but also ensures commendable ionic conductivity. Our post-gelation method yields gel polymer electrolytes that undergo rigorous evaluation, leading to an optimized version that stands out with its exceptional room-temperature ionic conductivity (2.94×10 -4  S cm -1 ) and outstanding toughness (11.9 MJ m -3 ). Moreover, it demonstrates a broad electrochemical window (4.73 V), remarkable stability across a 600-hour cycle test, a high capacity retention exceeding 80 % after 100 cycles at 0.2 C, and a noteworthy self-healing capability. This quasi-solid polymer electrolyte emerges as a promising contender to replace current liquid electrolyte solutions., (© 2024 Wiley-VCH GmbH.)

The aim of this study was to investigate the molecular mechanism by which miR-497-5p regulates neuronal injury after ischemic stroke through the BDNF/TrkB/Akt signaling pathway. PC12 cells were used to construct a stroke injury model by oxygen-glucose deprivation/reoxygenation (OGD/R). The expression level of miR-497-5p was measured by RT-qPCR. CCK-8 kit was used to detect cell viability. Cell apoptosis and reactive oxygen species (ROS) were detected by flow cytometry. MDA and SOD detection kits were used to detect MDA content and SOD activity. A double luciferase reporter system was used to verify the targeting relationship between miR-497-5p and BDNF. The expression of BDNF, TrkB, p-TrkB, Akt and p-Akt was detected by Western blot. We have found that miR-497-5p expression was inhibited after treatment with OGD/R. Simultaneously, cell apoptosis, MDA content and ROS were upregulated, while cell viability and SOD were significantly decreased in PC12 cells. The effects of OGD/R on PC12 cells were reversed with the downregulation of miR-497-5p. A double luciferase reporter assay demonstrated that miR-497-5p negatively targets BDNF. BDNF inhibited cell apoptosis and oxidative stress injury in PC12 cells. These findings suggest that miR-497-5p aggravates neuronal injury in experimental model of ischemic stroke by inhibiting the BDNF/TrkB/PI3K/Akt signaling pathway.