A rational design of functionalized black phosphorus cooperates with piperazine pyrophosphate to significantly suppress the fire hazards of polypropylene.

The flammability of polypropylene (PP) not only has negative effects on human health but also causes environmental pollution. Herein, from the molecular polarity point of view, rationally designed hyperbranched charring foaming agents (HCFA) modified black phosphorus nanosheets by in situ polymerization to solve the fire hazards of PP. Based on the UL-94 test V-0 rating, the conventional flame retardant of piperazine pyrophosphate (PAPP) is substituted partly by the BP@PPC. Surprisingly, compared with 27 wt% of PAPP/PP, composites consisting of only 2 wt% of BP@PPC and 20 wt% PAPP/PP also passes the V-0 rating. The results of the cone calorimeter test confirmed that adding BP@PPC decreases the total heat release (THR) and peak heat release (PHRR) by a large amount, which are decreased by 23.4%, 85.8% respectively compared with PP. Moreover, it is uncommon for the fire growth index of BP@PPC composites to be 66.7% lower than that of PAPP/PP composites. In addition, the incorporation of BP@PPC has almost no impact on the mechanical characteristics of PP composites. This study offers a reference for combining established flame retardants with novel compounds to modify the burning behaviors of PP.

Revealing and modeling of fire products in gas-phase for epoxy/black phosphorus-based nanocomposites.

This work aims at revealing and optimizing the mechanism, to promote the design of phosphorus-based flame retardants (PFRs) for controlling the spread of fire risk caused by the continuous spread of polymers. Herein, we synthesized about 10 nm TiO2 grown in situ on the surface of BP through a simple hydrothermal procedure to introduce it into epoxy (EP/BP-TiO2). In the first place, EP/BP-TiO22.0 nanocomposite achieves a reduction of 58.96% and 50.35% in PHRR and THR, respectively. Secondly, the pyrolysis of BP from Pn to P4, P3 and P2 is revealed. As a guide, P4 is established as a characteristic product of the analytical model for evaluating the effects in the gas phase for BP-based hybrids. Finally, this work clarifies the enhancement path for BP-TiO2 is optimized for the capturing of OH· and H· radicals by P4(POx). Crucially, this study reveals and controls the mechanism of the BP-based hybrids at the molecular level, which is expected to provide a promising analytical model for broad market PFRs design to address the risks and challenges of casualties and ecology caused by composites fire.

Anti-pseudo-allergic components in licorice extract inhibit mast cell degranulation and calcium influx.

Pseudo-allergic reactions (PARs) widely occur upon application of drugs or functional foods. Anti-pseudo-allergic ingredients from natural products have attracted much attention. This study aimed to investigate anti-pseudo-allergic compounds in licorice. The anti-pseudo-allergic effect of licorice extract was evaluated in rat basophilic leukemia 2H3 (RBL-2H3) cells. Anti-pseudo-allergic compounds were screened by using RBL-2H3 cell extraction and the effects of target components were verified further in RBL-2H3 cells, mouse peritoneal mast cells (MPMCs) and mice. Molecular docking and human MRGPRX2-expressing HEK293T cells (MRGPRX2-HEK293T cells) extraction were performed to determine the potential ligands of MAS-related G protein-coupled receptor-X2 (MRGPRX2), a pivotal target for PARs. Glycyrrhizic acid (GA) and licorice chalcone A (LA) were screened and shown to inhibit Compound48/80-induced degranulation and calcium influx in RBL-2H3 cells. GA and LA also inhibited degranulation in MPMCs and increase of histamine and TNF-α in mice. LA could bind to MRGPRX2, as determined by molecular docking and MRGPRX2-HEK293T cell extraction. Our study provides a strong rationale for using GA and LA as novel treatment options for PARs. LA is a potential ligand of MRGPRX2.

Anti-pseudo-allergic components in licorice extract inhibit mast cell degranulation and calcium influx / 中国天然药物

Pseudo-allergic reactions (PARs) widely occur upon application of drugs or functional foods. Anti-pseudo-allergic ingredients from natural products have attracted much attention. This study aimed to investigate anti-pseudo-allergic compounds in licorice. The anti-pseudo-allergic effect of licorice extract was evaluated in rat basophilic leukemia 2H3 (RBL-2H3) cells. Anti-pseudo-allergic compounds were screened by using RBL-2H3 cell extraction and the effects of target components were verified further in RBL-2H3 cells, mouse peritoneal mast cells (MPMCs) and mice. Molecular docking and human MRGPRX2-expressing HEK293T cells (MRGPRX2-HEK293T cells) extraction were performed to determine the potential ligands of MAS-related G protein-coupled receptor-X2 (MRGPRX2), a pivotal target for PARs. Glycyrrhizic acid (GA) and licorice chalcone A (LA) were screened and shown to inhibit Compound48/80-induced degranulation and calcium influx in RBL-2H3 cells. GA and LA also inhibited degranulation in MPMCs and increase of histamine and TNF-α in mice. LA could bind to MRGPRX2, as determined by molecular docking and MRGPRX2-HEK293T cell extraction. Our study provides a strong rationale for using GA and LA as novel treatment options for PARs. LA is a potential ligand of MRGPRX2.

Tanshinone IIA suppresses ovarian cancer growth through inhibiting malignant properties and angiogenesis.

BACKGROUND: In Chinese herbal medicine, Tanshinone IIA (Tan-IIA) is one of the main compounds extracted from Salvia miltiorrhiza Bunge. Tan-IIA has been demonstrated to inhibit the growth of various tumors. However, the detailed molecular and cellular mechanisms of the antitumor effect of Tan-IIA have yet to be fully illuminated. METHODS: A2780 and ID-8 were treated with 0, 1.2, 2.4, 4.8, or 9.6 µg/mL Tan-IIA for 24 hours. Cell counting Kit-8 assay and EdU staining were used to evaluate cell proliferation. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and flow cytometry were performed to analyze apoptosis. Western blot was carried out to determine the protein levels. Flow cytometry was used for cell cycle analysis. The levels of mRNA expression were analyzed by real-time polymerase chain reaction. The anti-tumor effect of Tan-IIA was observed in a tumor-bearing mouse model. RESULTS: Tan-IIA inhibited the proliferation of ovarian cancer cells in a dose-dependent manner by inducing G2/M phase arrest. It also down-regulated B-cell lymphoma 2 (Bcl-2) and up-regulated Bcl-2-associated X protein (Bax) in ovarian cancer cells to induce apoptosis, and suppressed cell migration by inhibiting focal adhesion kinase phosphorylation. Tan-IIA significantly reduced vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX2) mRNA expression in ovarian cancer cells. In vivo, Tan-IIA significantly inhibited tumor growth by inducing apoptosis and promoting anti-angiogenesis. CONCLUSIONS: The results of this study shed light on the molecular and cellular mechanisms for the antitumor effect of Tan-IIA.

Naringin Stimulates Osteogenic Differentiation of Rat Bone Marrow Stromal Cells via Activation of the Notch Signaling Pathway.

Naringin is a major flavonoid found in grapefruit and is an active compound extracted from the Chinese herbal medicine Rhizoma Drynariae. Naringin is a potent stimulator of osteogenic differentiation and has potential application in preventing bone loss. However, the signaling pathway underlying its osteogenic effect remains unclear. We hypothesized that the osteogenic activity of naringin involves the Notch signaling pathway. Rat bone marrow stromal cells (BMSCs) were cultured in osteogenic medium containing-naringin, with or without DAPT (an inhibitor of Notch signaling), the effects on ALP activity, calcium deposits, osteogenic genes (ALP, BSP, and cbfa1), adipogenic maker gene PPARγ2 levels, and Notch expression were examined. We found that naringin dose-dependently increased ALP activity and Alizarin red S staining, and treatment at the optimal concentration (50 µg/mL) increased mRNA levels of osteogenic genes and Notch1 expression, while decreasing PPARγ2 mRNA levels. Furthermore, treatment with DAPT partly reversed effects of naringin on BMSCs, as judged by decreases in naringin-induced ALP activity, calcium deposits, and osteogenic genes expression, as well as upregulation of PPARγ2 mRNA levels. These results suggest that the osteogenic effect of naringin partly involves the Notch signaling pathway.