Facile construction of 2-pyrones under carbene catalysis.

2-Pyrones are valuable structural motifs in organic chemistry, found in numerous natural products and pharmaceuticals. The synthesis of these heterocycles has been significantly advanced by the application of N-Heterocyclic Carbene (NHC) catalysis. This review examines the recent advancements in NHC-catalyzed synthesis of 2-pyrones, highlighting key methodologies, mechanisms, and synthetic applications. NHC catalysis has revolutionized the synthesis of 2-pyrones, providing efficient, selective, and versatile methods for constructing these valuable heterocycles.

Wafer-Scale Synthesis of Highly Oriented 2D Topological Semimetal PtTe2 via Tellurization.

Platinum ditelluride (1T-PtTe2) is a two-dimensional (2D) topological semimetal with a distinctive band structure and flexibility of van der Waals integration as a promising candidate for future electronics and spintronics. Although the synthesis of large-scale, uniform, and highly crystalline films of 2D semimetals system is a prerequisite for device application, the synthetic methods meeting these criteria are still lacking. Here, we introduce an approach to synthesize highly oriented 2D topological semimetal PtTe2 using a thermally assisted conversion called tellurization, which is a cost-efficient method compared to the other epitaxial deposition methods. We demonstrate that achieving highly crystalline 1T-PtTe2 using tellurization is not dependent on epitaxy but rather relies on two critical factors: (i) the crystallinity of the predeposited platinum (Pt) film and (ii) the surface coverage ratio of the Pt film considering lateral lattice expansion during transformation. By optimizing the surface coverage ratio of the epitaxial Pt film, we successfully obtained 2 in. wafer-scale uniformity without in-plane misalignment between antiparallelly oriented domains. The electronic band structure of 2D topological PtTe2 is clearly resolved in momentum space, and we observed an interesting 6-fold gapped Dirac cone at the Fermi surface. Furthermore, ultrahigh electrical conductivity down to ∼3.8 nm, which is consistent with that of single crystal PtTe2, was observed, proving its ultralow defect density.

Direct Observation of Room-Temperature Magnetic Skyrmion Motion Driven by Ultra-Low Current Density in Van Der Waals Ferromagnets.

The recent discovery of room-temperature ferromagnetism in 2D van der Waals (vdW) materials, such as Fe3GaTe2 (FGaT), has garnered significant interest in offering a robust platform for 2D spintronic applications. Various fundamental operations essential for the realization of 2D spintronics devices are experimentally confirmed using these materials at room temperature, such as current-induced magnetization switching or tunneling magnetoresistance. Nevertheless, the potential applications of magnetic skyrmions in FGaT systems at room temperature remain unexplored. In this work, the current-induced generation of magnetic skyrmions in FGaT flakes employing high-resolution magnetic transmission soft X-ray microscopy is introduced, supported by a feasible mechanism based on thermal effects. Furthermore, direct observation of the current-induced magnetic skyrmion motion at room temperature in FGaT flakes is presented with ultra-low threshold current density. This work highlights the potential of FGaT as a foundation for room-temperature-operating 2D skyrmion device applications.

Macranthoidin B (MB) Promotes Oxidative Stress-Induced Inhibiting of Hepa1-6 Cell Proliferation via Selenoprotein.

The aim of this study was to investigate the role of selenoproteins in Macranthoidin B (MB) with regard to the inhibition of hepa1-6 cell proliferation. The CCK8 method was used to detect the inhibition rate in hepa1-6 cell of proliferation. The production of ROS, MDA, GSH levels, and GSH-Px and SOD activities was detected according to corresponding reagent kits. We determined the mRNA expressions of 25 selenoproteins in hepa1-6 cells via real-time quantitative PCR (qRT-PCR); moreover, the heat map and principal component analysis were used for further bioinformatics analysis. The results revealed that with an increasing concentration of MB, the inhibitory effect on hepa1-6 cell proliferation intensified. Compared with the control group, the treatment group showed significantly increased ROS levels, elevated MDA contents, and decreased GSH level, GSH-Px activity, and SOD activity. Increasing MB concentration treatment induced remarkable degradation of Txnrd1, Txnrd2, Txnrd3, Gpx1, Gpx2, Gpx3, Gpx6, Dio1, Dio2, Selt, Selp, Selh, Selk, Selw, Seln, and Dio3. Principal component analysis revealed that Txnrd 3, Selk, Selo, Selw, Selt, Dio2, Txnrd1, Dio3, Gpx6, and Dio1 were highly correlated with MB. In conclusion, MB dose dependently inhibited hepa1-6 cell proliferation and induced oxidative stress. Based on bioinformatics analysis, with MB treatment, Txnrd 3, Selk, Selo, Selw, Selt, Dio2, Txnrd1, Dio3, Gpx6, and Dio1 exhibited critical role in the inhibition of hepa1-6 cells proliferation. The functions of these selenoproteins were associated with oxidative stress.

The Hypoglycemic Effect of JinQi Jiangtang Tablets Is Partially Dependent on the Palmatine-Induced Activation of the Fibroblast Growth Factor Receptor 1 Signaling Pathway.

JinQi Jiangtang tablet (JQJTT) is a Chinese patent medicine that has been shown to be beneficial for patients with diabetes both preclinically and clinically; however, the molecular mechanism underlying the effects of JQJTT remains unclear. In this study, surface plasmon resonance fishing was employed to identify JQJTT constituent molecules that can specifically bind to fibroblast growth factor receptor 1 (FGFR1), leading to the retrieval of palmatine (PAL), a key active ingredient of JQJTT. In vivo and in vitro experiments demonstrated that PAL can significantly stimulate FGFR1 phosphorylation and upregulate glucose transporter type 1 (GLUT-1) expression, thereby facilitating glucose uptake in insulin resistance (IR) HepG2 cells as well as alleviating hyperglycemia in diabetic mice. Our results revealed that PAL functions as an FGFR1 activator and that the hypoglycemic effect of JQJTT is partially dependent on the PAL-induced activation of the FGFR1 pathway. In addition, this study contributed to the understanding the pharmacodynamic basis and mechanism of action of JQJTT and provided a novel concept for future research on PAL.

Schisandrin B Induced ROS-Mediated Autophagy and Th1/Th2 Imbalance via Selenoproteins in Hepa1-6 Cells.

Schisandrin B (Sch B) is well-known for its antitumor effect; however, its underlying mechanism remains confusing. Our study aimed to investigate the role of selenoproteins in Sch B-induced autophagy and Th1/Th2 imbalance in Hepa1-6 cells. Hepa1-6 cells were chosen to explore the antitumor mechanism and were treated with 0, 25, 50, and 100 µM of Sch B for 24 h, respectively. We detected the inhibition rate of proliferation, transmission electron microscopy (TEM), monodansylcadaverine (MDC) staining, reactive oxygen species (ROS) level and oxidative stress-related indicators, autophagy-related genes, related Th1/Th2 cytokines, and selenoprotein mRNA expression. Moreover, the heat map, principal component analysis (PCA), and correlation analysis were used for further bioinformatics analysis. The results revealed that Sch B exhibited well-inhibited effects on Hepa1-6 cells. Subsequently, under Sch B treatment, typical autophagy characteristics were increasingly apparent, and the level of punctate MDC staining enhanced and regulated the autophagy-related genes. Overall, Sch B induced autophagy in Hepa1-6 cells. In addition, Sch B-promoted ROS accumulation eventually triggered autophagy initiation. Results of Th1 and Th2 cytokine mRNA expression indicated that Th1/Th2 immune imbalance was observed by Sch B treatment in Hepa1-6 cells. Intriguingly, Sch B downregulated the majority of selenoprotein expression. Also, the heat map results observed significant variation of autophagy-related genes, related Th1/Th2 cytokines, and selenoprotein expression in response to Sch B treatment. PCA outcome suggested the key role of Txnrd1, Txnrd3, Selp, GPX2, Dio3, and Selr with its potential interactions in ROS-mediated autophagy and Th1/Th2 imbalance of Hepa1-6 cells. In conclusion, Sch B induced ROS-mediated autophagy and Th1/Th2 imbalance in Hepa1-6 cells. More importantly, the majority of selenoproteins were intimately involved in the process of autophagy and Th1/Th2 imbalance, Txnrd3, Selp, GPX2, Dio3, and Selr had considerable impacts on the process.

Optimization the extraction of anthocyanins from blueberry residue by dual-aqueous phase method and cell damage protection study.

Blueberry residue is usually discarded as waste, but has a high anthocyanins content. The extraction method of anthocyanins from blueberry residue with ultrasonic assisted dual-aqueous phase system was optimized. In terms of the principle of central group and design (CCD) experimental design, three-factor and five-level response surface analysis was adopted to optimize the extraction conditions with the extraction rate of anthocyanins. The optimum extraction rate of anthocyanin was 12.372 ± 0.078 mg/g. Anthocyanin extract could protect the pBR322 DNA oxidative damage induced by Fenton reagent, increase the superoxide dismutase(SOD) and glutathione peroxidase (GSH-Px) enzyme activities, and decrease the H2O2-induced cell apoptosis of human normal liver cell (LO2 cell). The study indicates that the extraction rate of anthocyanin was increased by optimized ultrasonic assisted dual-aqueous phase system. The anthocyanin extract could protect DNA and LO2 cell from oxidative damage.

Endophytic Fungi from Dalbergia odorifera T. Chen Producing Naringenin Inhibit the Growth of Staphylococcus aureus by Interfering with Cell Membrane, DNA, and Protein.

This study focused on the antibacterial effects of the endophytic fungi producing naringenin from Dalbergia odorifera T. Chen against Staphylococcus aureus. The antibacterial activity was measured by the inhibition diameters, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The time-killing curve was also used to evaluate its antibacterial efficacy. The results of antibacterial activity determinations showed that endophytic fungi secondary metabolites can inhibit the growth of five pathogenic bacteria (S. aureus, Escherichia coli, Salmonella enteritidis, Pseudomonas aeruginosa, and Bacillus subtilis) and the most sensitive strain was S. aureus that had the MIC and MBC values of 0.13 and 0.50 mg/mL, respectively. The membrane permeability study was measured by a DNA leakage assay and electrical conductivity assay. Furthermore, the whole-cell protein lysates and DNA fragmentation assay was evaluated. The morphology of S. aureus treated with the endophytic fungi products was observed by scanning electron microscopy (SEM). The probable antibacterial mechanism of endophytic fungi secondary metabolites was the increased membrane permeability that leads to leaks of nucleic acids and proteins. SEM results further confirmed that the extracts can interfere with the integrity of S. aureus cell membrane and further inhibit the growth of bacteria, resulting in the death of bacteria. This study provides a new perspective for the antibacterial functions of endophytic fungi secondary metabolites for biomedical applications.

Optimization of trypsin extraction technology of Allium cepa L. polysaccharide by response surface methodology and the antitumor effects through immunomodulation.

The trypsin-assisted extraction of polysaccharides from Allium cepa L. was optimized using the response surface methodology (RSM). The optimum extraction conditions were extraction temperature, extraction time, extraction pH, and enzyme amount of 37.16°C, 180 min, 8.57, and 5.16%, respectively. Under the optimized conditions, the yield of A. cepa L. polysaccharides (ACP) reached 9.69%, which was comparable with the predicted yield (9.73%). Mid- and high-dose ACP significantly inhibited the tumor growth (43.93%) and the tumor inhibition percentage (38.05%), which were more than 30%. The ACP could extend the survival time of H22 ascites tumor-bearing mice. Furthermore, the ACP could reduce the thymus and the spleen atrophy and significantly promoted the Con A-induced proliferation of splenocytes and elevated the serum IFN-γ and IL-2 levels. Therefore, the ACP could inhibit the tumor growth in tumor-bearing mice and regulated the immune function of mice. Practical ApplicationsThe trypsin-assisted extraction has high efficiency, is carried out through the polysaccharide extraction and the deproteinization at the same time, and is more convenient and fast than traditional methods. No detailed study on the optimization of the trypsin extraction of onion polysaccharides is available. Thus, this experiment aims to use the BBD (4 factors and 3 levels) to optimize the roles of extraction temperature, extraction time, extraction pH, and amount of enzyme on the yield of polysaccharides obtained from the fruit of A. cepa L. In addition, when looking for high-quality biological functional principles for the pharmaceutical industry, the antitumor activity of ACP was evaluated. A. cepa L. is one of the most widely cultivated and consumed crops worldwide. Polysaccharides are the main active ingredient, and studies have shown that a high intake of Allium vegetables is associated with reduced risk of cancers.

A new benzophenone with biological activities purified from Aspergillus fumigatus SWZ01.

Strain SZW01 was isolated from sea sediment collected from Shenzhen in Guangdong province, China, and was later identified as Aspergillus fumigatus by16S rDNA sequence analysis. Various chromatographic processes led to the isolation and purification of three compounds from the fermentation culture of SZW01, including a new compound, 2,6'-dihydroxy-2,4'dimethoxy-8'-methyl-6-methoxy-acyl-ethyl-diphenylmethanone (1), and two known compounds: fumigaclavine C (2) and alternarosin A (3), as characterised by UV, IR, 1 D, 2 D-NMR and MS data. The antioxidant and α-glucosidase inhibitory activities of these compounds were evaluated. The result illustrated that compound 1 exhibited a moderate antioxidant activity and stronger α-glucosidase inhibitory activity than acarbose.