Pharmaceutical Values of Calycosin: One Type of Flavonoid Isolated from Astragalus

Astragalus is a popular Materia Medica in China, and it could be applied in the treatment of various diseases. It contains a variety of chemically active ingredients, such as saponins, flavonoids, and polysaccharides. Plant-derived bioactive chemicals are considered natural, safe, and beneficial. Among the infinite plant-identified and isolated molecules, flavonoids have been reported to have positive effects on human health. Calycosin is the most important active flavonoid substance identified predominantly within this medicinal plant. In recent years, calycosin has been reported to have anticancer, antioxidative, immune-modulatory, and estrogenic-like properties. This review collected recent relevant literatures on calycosin and summarized its potential pharmaceutical properties and working mechanism involved, which provided solid basis for future clinical research

Improvement in the tribocorrosion performance of CrCN coating by multilayered design for marine protective application

Steel structures significantly degrades owing to tribology and corrosion in aggressive marine environment and is unavoidable. Chromium nitride (CrN) based coatings material has aroused great interest as one of the most promising protective system in the marine equipment or its components. In the present study, we provided insights for the tribocorrosion mechanism of CrN and CrCN monolayers as well as CrN/CrCN multilayered coatings deposited on steel substrates via a multi-arc ion method. Field emission scanning electron microscopy (FESEM) and transmission electron microscope (TEM) revealed that the design of multilayer structure could interrupt the continuous growth of columnar crystals and making the coating denser. Furthermore, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) results confirmed the CrN/CrCN multilayered coating presented a high content of graphite-like phase and hard Cr-C compounds, which might play a key role enhancing lubrication and hardness. In particular, tribocorrosion tests in artificial seawater showed that the as-deposited CrN/CrCN multilayered coating could demonstrate significant improvement of tribocorrosion resistance compared to the CrN and CrCN monolayers coatings. The corresponded mechanisms were discussed in term of the coatings microstructure and tribocorrosion behaviors

Disruption of YY1-EZH2 Interaction Using Synthetic Peptides Inhibits Breast Cancer Development

Enhancer of zeste homolog 2 (EZH2) is a methyltransferase to mediate lysine 27 trimethylation in histone H3 (i.e., H3K27me3) and repress gene expression. In solid tumors, EZH2 promotes oncogenesis and is considered a therapeutic target. As a transcription factor, Yin Yang 1 (YY1) recruits EZH2 through its oncoprotein binding (OPB) domain to establish gene repression. In this study, we mapped the YY1 protein binding (YPB) domain on EZH2 to a region of 27 amino acids. Both YPB and OPB domain synthetic peptides could disrupt YY1EZH2 interaction, markedly reduce breast cancer cell viability, and efficiently inhibit tumor growth in a xenograft mouse model. We analyzed MDA-MB-231 cells treated with YPB, OPB, and control peptides by chromatin immunoprecipitation DNA sequencing (ChIP-seq) using an antibody against H3K27me3. YPB and OPB treatments altered H3K27me3 on 465 and 1137 genes, respectively, compared to the control. Of these genes, 145 overlapped between the two peptides. Among them, PTENP1, the PTEN pseudogene, showed reduced H3K27me3 signal when treated by either YPB or OPB peptide. Consistently, the two peptides enhanced both PTENP1 and PTEN expression with concomitantly reduced AKT activation. Further studies validated PTENP1′s contribution to the anticancer activity of YPB and OPB peptides

Type‐II Dirac Nodal Lines in a Double‐Kagome‐Layered Semimetal

Abstract Lorentz‐violating type‐II Dirac nodal line semimetals (DNLSs), hosting curves of band degeneracy formed by two dispersion branches with the same sign of slope, represent a novel state of matter. While being studied extensively in theory, convincing experimental evidence of type‐II DNLSs remain elusive. Recently, vanadium‐based kagome materials have emerged as a fertile ground to study the interplay between lattice symmetry and band topology. This work studies the low‐energy band structure of double‐kagome‐layered CsV8Sb12 and identifies it as a scarce type‐II DNLS protected by mirror symmetry. This work observes multiple DNLs consisting of type‐II Dirac cones close to or almost at the Fermi level via angle‐resolved photoemission spectroscopy (ARPES), which provides an electronic explanation for the nonsaturating magnetoresistance effect as observed. First‐principles theory analyses show that spin‐orbit coupling only opens a small gap, resulting in effectively gapless ARPES spectra, yet generating large spin Berry curvature. These type‐II DNLs, together with the interaction between a low‐energy van Hove singularity and quasi‐one‐dimensional band as observed in the same material, suggest CsV8Sb12 as an ideal platform for exploring novel transport properties