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Within cell plasma membranes, unsaturated lipids are asymmetrically distributed over the inner and outer leaflets, offering an attractive local structural feature. However, the mechanism to keep lipid transmembrane asymmetry and the closely related transmembrane movement (flip-flop) for unsaturated lipids remain poorly understood. Here, we applied sum frequency generation vibrational spectroscopy to investigate this lipid transmembrane asymmetry upon mimicking the cell membrane homeostatic processes. On the one hand, unsaturated lipids were found to hinder the flip-flop process and preserve lipid transmembrane asymmetry in model cell membranes, owing to the steric hindrance caused by their bent tails. On the other hand, local unsaturated lipids in the mixed unsaturated/saturated lipid bilayer were conducive to the formation of the local asymmetry. Therefore, lipid unsaturation can be recognized as an intrinsic key factor to form and maintain lipid transmembrane asymmetry in cell membranes. [ABSTRACT FROM AUTHOR]

Anisotropy has played a critical role in many material systems, but its controllable creation and modulation have been a long-lasting challenge for the scientific communities. Polarization-addressed anisotropy appears more attractive among all approaches due to its excellent controllability, simplicity, and accuracy, but only a limited number of material systems are applicable for such a concept, which are largely focused on oriented growth. Here, we establish a polarization-dependent anisotropic etching system made of Au@oligomer core–shell nanoparticles (NPs). As the oligomer coatings can be photochemically degraded via two-photon photolithography, the plasmonic near-field enhancement supported by the Au NP cores renders much faster degradation of the oligomer shells along the polarization, resulting in anisotropic Au@oligomer hybrid NPs. Such shape anisotropy leads to polarization-dependent photoluminescence with embedded dyes of methylene blue, which can be used as single-particle-based polarization detector. The oligomer lobes capped at the sides of the Au NP can also function as a protection agent for anisotropic photochemical growth of Au NPs, which evolve into Au nanorods and mushrooms with controlled irradiation time. Such polarization-directed etching of oligomer shells has unique advantages of high local-selectivity, controllability, and versatility for on-chip nanofabrication, which opens many new opportunities for integrated nanophotonic devices.

Aims: This study aimed to investigate the anti‐inflammatory and odontoblastic effects of cerium‐containing mesoporous bioactive glass nanoparticles (Ce‐MBGNs) on dental pulp cells as novel pulp‐capping agents. Methodology: Ce‐MBGNs were synthesized using a post‐impregnation strategy based on the antioxidant properties of Ce ions and proposed the first use of Ce‐MBGNs for pulp‐capping application. The biocompatibility of Ce‐MBGNs was analysed using the CCK‐8 assay and apoptosis detection. Additionally, the reactive oxygen species (ROS) scavenging ability of Ce‐MBGNs was measured using the 2,7‐Dichlorofuorescin Diacetate (DCFH‐DA) probe. The anti‐inflammatory effect of Ce‐MBGNs on THP‐1 cells was further investigated using flow cytometry and quantitative real‐time polymerase chain reaction (RT‐qPCR). Moreover, the effect of Ce‐MBGNs on the odontoblastic differentiation of the dental pulp cells (DPCs) was assessed by combined scratch assays, RT‐qPCR, western blotting, immunocytochemistry, Alizarin Red S staining and tissue‐nonspecific alkaline phosphatase staining. Analytically, the secretions of tumour necrosis factor‐α (TNF‐α) and interleukin‐1β (IL‐1β) were detected with enzyme‐linked immunosorbent assay (ELISA). Results: Ce‐MBGNs were confirmed to effectively scavenge ROS in THP‐1‐derived macrophages and DPCs. Flow cytometry and RT‐qPCR assays revealed that Ce‐MBGNs significantly inhibited the M1 polarization of macrophages (Mφ). Furthermore, the protein levels of TNF‐α and IL‐1β were downregulated in THP‐1‐derived macrophages after stimulation with Ce‐MBGNs. With a step‐forward virtue of promoting the odontoblastic differentiation of DPCs, we further confirmed that Ce‐MBGNs could regulate the formation of a conductive immune microenvironment with respect to tissue repair in DPCs, which was mediated by macrophages. Conclusions: Ce‐MBGNs protected cells from self‐produced oxidative damage and exhibited excellent immunomodulatory and odontoblastic differentiation effects on DPCs. As a pulp‐capping agent, this novel biomaterial can exert anti‐inflammatory effects and promote restorative dentine regeneration in clinical treatment. We believe that this study will stimulate further correlative research on the development of advanced pulp‐capping agents. [ABSTRACT FROM AUTHOR]

Objective To assess the clinical effect of oral nutritional supplements in patients with colorectal cancer after emergency surgery. Methods Based on a retrospective comparative analytic design, 38 CRC patients undergoing emergency surgery were divided into two groups according to nutrition support methods: TPN and PN+ONS groups. We collected the clinical data of two groups, including the number of blood lymphocyte and albumin before surgery and on the 1st and 7th postoperative day, postoperative complication, total length of stay and postoperative length of stay. Results The age, gender, operation time and the amount of operative blood loss volume did not show statistically significant difference between two groups(P > 0.05). PN+ONS group had lower postoperative infection rate and complication rate and shorter total length of stay, but the difference was not statistically significant between two groups(P > 0.05). Conclusion The application of ONS may be helpful to reduce postoperative complications and shorten the length of stay in CRC patients after emergency surgery.