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A strategy for fabricating microcrystalline cellulose-Ti3C2Tx (MCC-MXene) nanocomposite films with high relative permittivity, high thermal conductivity, and excellent mechanical properties was developed. The MCC-MXene nanocomposite film was fabricated by casting a solution containing N,N-dimethylacetamide/lithium chloride (DMAc/LiCl)-soluble MCC and DMAc-dispersible MXene nanosheets, followed by humidity control drying. The MXene nanosheets greatly enhanced the permittivity of the nanocomposite films owing to interfacial polarization. Thus, the nanocomposite film with 20 wt.% MXene content achieved a desirable permittivity of 71.4 at 102 Hz (a 770% improvement against that of neat cellulose), while the dielectric loss only increased by 1.8 times (from 0.39 to 0.70). The obtained nanocomposite films with 20 wt.% and 30 wt.% MXene exhibited remarkable in-plane thermal conductivities of 8.523 and 9.668 W·m−1·K−1, respectively, owing to the uniform dispersion and self-alignment of the MXene layered structure. Additionally, the uniformly dispersed MXene nanosheets in the MCC network with interfacial interaction (hydrogen bonding) and mechanical entanglement endowed the nanocomposite films with excellent mechanical properties and flexibility. Furthermore, the thermal stability, water resistance, and antibacterial properties of the nanocomposite films were effectively improved with the introduction of MXene. Moreover, using DMAc/LiCl as the solvent system not only improves the compatibility between MCC and MXene but also avoids the problem of easy oxidation of MXene in aqueous systems. With the high stability of the MCC-MXene solution and enhanced properties of the MCC-MXene films, the proposed strategy manifests great potential for fabricating natural biomass-based dielectric materials. [ABSTRACT FROM AUTHOR]

Premature drug release and poor controllability is a challenge in the practical application of tumor therapy, which may lead to poor chemotherapy efficacy and severe adverse effects. In this study, a reactive oxygen species (ROS)-cleavable nanoparticle system (MXene-TK-DOX@PDA) was designed for effective chemotherapy drug delivery and antibacterial applications. Doxorubicin (DOX) was conjugated to the surface of (3-aminopropyl)triethoxysilane (APTES)-functionalized MXene via an ROS-cleavable diacetoxyl thioketal (TK) linkage. Subsequently, the surfaces of the MXene nanosheets were coated with pH-responsive polydopamine (PDA) as a gatekeeper. PDA endowed the MXene-TK-DOX@PDA nanoparticles with superior biocompatibility and stability. The MXene-TK-DOX@PDA nanoparticles had an ultrathin planar structure and a small lateral size of approximately 180 nm. The as-synthesized nanoparticles demonstrated outstanding photothermal conversion efficiency, superior photothermal stability, and a remarkable extinction coefficient (23.3 L g−1 cm−1 at 808 nm). DOX exhibited both efficient ROS-responsive and pH-responsive release performance from MXene-TK-DOX@PDA nanoparticles due to the cleavage of the thioketal linker. In addition, MXene-TK-DOX@PDA nanoparticles displayed high antibacterial activity against both Gram-negative Escherichia coli (E. coli) and Gram-positive Bacillus subtilis (B. subtilis) within 5 h. Taken together, we hope that MXene-TK-DOX@PDA nanoparticles will enrich the drug delivery system and significantly expand their applications in the biomedical field [ABSTRACT FROM AUTHOR]

Abstract: Porous TiO2 thin film of photocatalyst was synthesized by charged microemulsion templating. In the process, cationic polystytrene microemulsion (PSTM) was successfully added into the precursor solution of TiO2 (Ti-sol). The factors, such as the charged surfactant species, the amount of PSTM and pH of the solution mixture strongly affect the stability of the solution mixture. TiO2 film containing larger pores in diameter of 20–100nm was obtained after heat treatment and analyzed by BET and BJH. The addition of PSTM effectively influences crystal structure, specific surface area and morphology of thin films. The crystal particle growth of anatase phase is restrained by PSTM addition, and the addition of PSTM promotes the crystal phase transformation from anatase to rutile phase, as was testified by XRD, AFM and FT-IR. The photocatalytic degradation suggests that the optimal addition of PSTM (the volume ratio of PSTM and Ti-sol being 0.3) can reach a remarkable enhancement of photocatalytic activity of TiO2 films, shown by an increase of almost 66% of the apparent rate constant of degradation. [Copyright &y& Elsevier]

A group of previously undescribed diarylheptanoids with mono/di-glucose substitution, diodiarylheptosides A–F (1 – 6), together with six known diarylheptanoids (7 – 12) were isolated from the rhizomes of Dioscorea nipponica. Their structures were established by comprehensive UV, IR, HR-ESI-MS and NMR analyses, and their absolute configurations were determined by a comparison of calculated and experimental ECD, some with optical rotations, after acid-hydrolysis. Moreover, bioassay results showed that compounds 3 and 11 exhibited stronger NO inhibitions on lipopolysaccharides-induced RAW 264.7 cells, with the IC 50 values of 14.91 ± 0.62 and 12.78 ± 1.12 μM. [Display omitted] • Diodiarylheptosides A–F (1–6), a group of rare natural diarylheptanoids with mono/di-glucose substitution, were isolated from Dioscorea nipponica rhizomes. • Their absolute configurations were determined by a comparison of calculated and experimental ECD, some with optical rotations, after acid-hydrolysis. • Compounds 3 and 11 showed stronger NO inhibitions on LPS-induced RAW 264.7 cells. [ABSTRACT FROM AUTHOR]

Purpose: To identify predictors and develop a prognostic nomogram for clinically significant intraocular lens (IOL) tilt and decentration in vitrectomized eyes., Setting: Zhongshan ophthalmic center, Guangzhou, China., Design: Prospective observational study., Methods: Patients with previous pars plana vitrectomy who underwent phacoemulsification with IOL implantation were enrolled in this study. The tilt and decentration of the lens and IOL were assessed by a swept-source anterior segment optical coherence tomography (CASIA2). Multiple logistic regression analysis and prognostic nomogram models were used to explore factors associated with clinically significant IOL tilt and decentration (defined as tilt ≥7 degrees and decentration ≥0.4 mm)., Results: 375 patients (375 eyes) with a mean age of 56.1 ± 9.81 years were included. Lens tilt (odds ratio [OR] = 1.44), lens decentration (OR = 1.74), lens diameter (OR = 0.49), and hydrophilic IOL (OR = 2.36) were associated with IOL tilt over 7 degrees (all P < .05). Lens tilt (OR = 1.24), lens decentration (OR = 2.30), and incomplete capsulorhexis-IOL overlap (OR = 2.44) increased the risk of IOL decentration over 0.4 mm (all P < .05). Preoperative lens tilt together with lens decentration was identified as the strongest predictor of incident clinically significant IOL tilt (area under the curve [AUC] = 0.82, 95% CI, 0.76-0.88) and decentration (AUC: 0.84, 95% CI, 0.78-0.89), and the nomogram was constructed accordingly., Conclusions: The tilt and decentration of the crystalline lens, hydrophilic IOL, and incomplete capsulorhexis-IOL overlap were risk factors for clinically significant IOL misalignment. Clinicians could use a prognostic nomogram model based on the preoperative lens position to make a strategy for higher-risk patients., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of ASCRS and ESCRS.)

Objective: To investigate lipopolysaccharide (LPS)-induced changes of cytoskeletal filamentous actin in primary isolated pulmonary microvascular endothelial cells (PMVECs) from wild-type and RAGE knock-out mouse., Methods: The lungs of wild-type and RAGE knock-out mice were digested with collagenase type I to obtain endothelial cells purified by anti-CD31-coupled magnetic beads. The PMVEC identified by factor VIII labeling were stimulated with LPS at different concentrations and the changes of filamentous actin were observed by confocal microscopy., Results: The cultured primary cells showed typical endothelial cell phenotype as examined with factor VIII labeling. LPS stimulation caused rearrangement of the cytoskeletal filament F-actin in wild-type mouse PMVECs with stress fiber formation, but such changes were not obvious in RAGE knock-out mouse PMVECs., Conclusion: Mouse PMVECs of a high purity can be obtained by immune magnetic beads. RAGE is involved in LPS-induced destruction of mouse PMVEC cytoskeletons.

Aim: To investigate the effects of entero-hepatic bile acid circulation on the inter-digestive migrating myoelectrical complex (MMC) in rats., Methods: Thirty-two rats were divided into four groups. Three pairs of bipolar silver electrodes were chronically implanted in the antrum, duodenum and jejunum. Three groups of them were ligated around the upper part of common bile duct (CBD). The experiments were performed in conscious and fasting state. The gastrointestinal myoelectrical activity was recorded. Ursodeoxycholic acid (UDCA) and saline were then perfused into stomachs of two groups with CBD obstruction and the effects of them on the MMC were observed., Results: A typical pattern of MMC was observed in normal fasting rats. MMC of antral and duodenal origin disappeared temporarily in earlier stage of CBD obstruction. While MMC of jejunum origin appeared. increased MMC cycle duration was seen after 4 d in rats with CBD obstruction. The MMC after CBD obstruction was characterized by an increased duration of phase II-like activity and decreased duration of phase I and III activity. Perfusion into stomachs with UDCA resulted in a shorter MMC cycle duration and a longer duration of phase III of duodenal origin compared to the normal group., Conclusion: Entero-hepatic bile acid circulation initiates inter-digestive MMC of duodenal origin.