Ultra Fine Layered Silicate Synthesis from Synthetic Silicate Raw Material

This paper reports the results of experiments on ultra fine layered silicates Na-fluorotaeniolite and Na-fluorotetrasilicic mica synthesis in the melts prepared from reaction blends based on synthetic silicate raw material, namely synthetic magnesium silicate dihydrate (MSDH, MgO·SiO₂·2H₂O). The MSDH–Na₂SiF₆–LiF, MSDH–Na₂SiF₆–MgF₂ and MSDH–Na₂SiF₆–NaF blends, whose compositions are close to the stoichiometry of the Na-fluorotaeniolite (NaMg₂Li[Si₄O₁₀]F₂) and Na-fluorotetrasilicic mica (NaMg_2.5[Si₄O₁₀]F₂) were studied in the temperature range 1080–1225°C. Magnesium silicate dihydrate, the phase composition of synthesis products and layered silicates (Na-fluorotaeniolite and Na-fluorotetrasilicic mica) were examined using the crystal optical, X-ray diffraction at room and high temperatures, differential thermal and chemical analyses. It has been shown that studied blends possessed a high reactivity, owing to which the layered silicates were synthesized at lower temperatures (～180–300°C) and the duration of the synthesis was shortened severalfold. The maximal yield of the Na-fluorotetrasilicic mica was observed in the reaction blend with the Na₂SiF₆ and NaF as halogen-containing compounds. The specific effects of MSDH on the physicochemical processes proceeded during heat treatment of the reaction blends were described.     

Abiesanol A, a novel biflavanol with unique six connective hexacyclic rings isolated from Abies georgei

A novel biflavanol with unique six connective hexacyclic rings, abiesanol A (1), was isolated from the aerial parts of Abies georgei together with four known flavanols. The structure of new compound was elucidated mainly by the analysis of 1D and 2D NMR spectroscopic data. In addition, single-crystal X-ray diffraction analysis was adopted to confirm the structure of abiesanol A (1). In biological assay for inhibitory activities against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages, abiesanol A (1) showed potent effects at 50 μg/mL with the inhibition rate of 43.0%. Under the same concentration, abiesanol A (1) did not show any cytotoxicity against RAW264.7 macrophages.     

Aurones and Flavonols from Coreopsis lanceolata L. Flowers and Their Anti-Oxidant,Pro-Inflammatory Inhibition Effects,and Recovery Effects on Alloxan-Induced Pancreatic Islets in Zebrafish

(1) Background: Many flavonoids have been reported to exhibit pharmacological activity; a preparatory study confirmed that Coreopsis lanceolata flowers (CLFs) contained high flavonoid structure content; (2) Methods: CLFs were extracted in aqueous methanol (MeOH:H₂O = 4:1) and fractionated into acetic ester (EtOAc), normal butanol (n-BuOH), and H₂O fractions. Repeated column chromatographies for two fractions led to the isolation of two aurones and two flavonols; (3) Results: Four flavonoids were identified based on a variety of spectroscopic data analyses to be leptosidin (1), leptosin (2), isoquercetin (3), and astragalin (4), respectively. This is the first report for isolation of 2–4 from CLFs. High-performance liquid chromatography (HPLC) analysis determined the content levels of compounds 1–4 in the MeOH extract to be 2.8 ± 0.3 mg/g (1), 17.9 ± 0.9 mg/g (2), 3.0 ± 0.2 mg/g (3), and 10.9 ± 0.9 mg/g (4), respectively. All isolated compounds showed radical scavenging activities and recovery activities in Caco-2, RAW264.7, PC-12, and HepG2 cells against reactive oxygen species. MeOH extract, EtOAc fraction, and 1–3 suppressed NO formation in LPS-stimulated RAW 264.7 cells and decreased iNOS and COX-2 expression. Furthermore, all compounds recovered the pancreatic islets damaged by alloxan treatment in zebrafish; (4) Conclusions: The outcome proposes 1–4 to serve as components of CLFs in standardizing anti-oxidant, pro-inflammatory inhibition, and potential anti-diabetic agents.     

A new route for simple and rapid determination of hydrogen peroxide in RAW264.7 macrophages by microchip electrophoresis

A new method using MCE with LIF detection was developed for the determination of hydrogen peroxide (H₂O₂). Bis(p‐methylbenzenesulfonyl)dichlorofluorescein, a new fluorogenic reagent synthesized by our laboratory was employed as a labeling reagent, the derivatization reaction was performed in 0.10 M HEPES buffer (pH 7.4) for 30 min at 37°C. The detection of H₂O₂ was accomplished in 55 s, using a 40 mM HEPES buffer, 20% mannitol, pH 7.4, on a glass microchip. The RSDs of migration time and peak area were 1.8 and 3.7%, respectively. Method validation showed the linear response ranging from 0.50 to 50 μM with an LOD (S/N=3) of 0.20 μM (19.1 amol). The proposed method was applied to determine H₂O₂ in phorbol myristate acetate‐stimulated RAW264.7 macrophages, the concentration of H₂O₂ was found to be 1.86±0.05 μM; recoveries for macrophage samples were from 96.7 to 97.8%, within‐days and between‐days accuracies were 4.5% (n=5) and 6.8% (n=5), respectively.     

Rutin Inhibits Ox-LDL-Mediated Macrophage Inflammation and Foam Cell Formation by Inducing Autophagy and Modulating PI3K/ATK Signaling

Atherosclerosis (AS) is one of the leading causes of death among the elderly, and is primarily caused by foam cell generation and macrophage inflammation. Rutin is an anti-inflammatory, anti-oxidant, anti-allergic, and antiviral flavonoid molecule, known to have anti-atherosclerotic and autophagy-inducing properties, but its biological mechanism remains poorly understood. In this study, we uncovered that rutin could suppress the generation of inflammatory factors and reactive oxygen species (ROS) in ox-LDL-induced M2 macrophages and enhance their polarization. Moreover, rutin could decrease foam cell production, as shown by oil red O staining. In addition, rutin could increase the number of autophagosomes and the LC3II/I ratio, while lowering p62 expression. Furthermore, rutin could significantly inhibit the PI3K/ATK signaling pathway. In summary, rutin inhibits ox-LDL-mediated macrophage inflammation and foam cell formation by inducing autophagy and modulating PI3K/ATK signaling, showing potential in treating atherosclerosis.     

Synthesis and Investigation of Flavanone Derivatives as Potential New Anti-Inflammatory Agents

Flavonoids are polyphenols with broad known pharmacological properties. A series of 2,3-dihydroflavanone derivatives were thus synthesized and investigated for their anti-inflammatory activities. The target flavanones were prepared through cyclization of 2′-hydroxychalcone derivatives, the later obtained by Claisen–Schmidt condensation. Since nitric oxide (NO) represents an important inflammatory mediator, the effects of various flavanones on the NO production in the LPS-induced RAW 264.7 macrophage were assessed in vitro using the Griess test. The most active compounds were flavanone (4G), 2′-carboxy-5,7-dimethoxy-flavanone (4F), 4′-bromo-5,7-dimethoxy-flavanone (4D), and 2′-carboxyflavanone (4J), with IC50 values of 0.603, 0.906, 1.030, and 1.830 µg/mL, respectively. In comparison, pinocembrin achieved an IC₅₀ value of 203.60 µg/mL. Thus, the derivatives synthesized in this work had a higher NO inhibition capacity compared to pinocembrin, demonstrating the importance of pharmacomodulation to improve the biological potential of natural molecules. SARs suggested that the use of a carboxyl-group in the meta-position of the B-ring increases biological activity, whereas compounds carrying halogen substituents in the para-position were less active. The addition of methoxy-groups in the meta-position of the A-ring somewhat decreased the activity. This study successfully identified new bioactive flavanones as promising candidates for the development of new anti-inflammatory agents.     

多光纤波分复用网动态路由和波长分配算法

本文研究了多光纤波分复用光互连网的动态路由和波长分配问题,提出了基于分层图模型的两种动态路由算法,LG-1和LG-2.这两种算法将路由和波长分配问题转换为如何在分层图中支持尽可能多的光路.这使得设计者可以同时考虑路由和波长分配子问题,从而取得了更好的效果.计算机仿真表明基于分层图的算法大大优于传统的固定路由和动态路由算法.     

Detection of lipopolysaccharide induced inflammatory responses in RAW264.7 macrophages using atomic force microscope

In recent years, LPS activated RAW264.7 cells are widely used as an in vitro inflammatory model for the screen of effective anti-inflammation drugs and the investigation of exact anti-inflammation mechanism of these drugs. But up to now, there are few data about the effect of LPS on the morphology, especially on the membrane ultrastructure and bio-mechanical properties of RAW264.7 macrophages. In this work, the topographical and biophysical changes of RAW264.7 macrophages upon LPS stimulation are detected by high resolution atomic force microscopy (AFM). The AFM results suggested that LPS activated RAW264.7 macrophages changed to be much bigger than control cells with some holes emerged on cell surface. The size of membrane protein clusters and the roughness of membrane significantly increased after LPS exposure. In addition, the AFM force measurement results demonstrated that LPS stimulation increased the adhesion force of RAW264.7 macrophages, and also increased the stiffness of RAW264.7 macrophages, which were attributed to the re-distribution of intracellular F-actin structures induced by LPS. These findings suggested that LPS stimulation could also induce the pathophysiological changes of RAW264.7 macrophages, which would benefit our understanding of the inflammatory processes in macrophages upon pathogen stimulation at nano-scale.     

A new coumarin isolated from Sarcandra glabra as potential anti-inflammatory agent

One new coumarin, 3,5-dihydroxy-7-O-α-L-rhamno pyranosyl-2H-chromen-2-one (1), was isolated from the whole plant of Sarcandra glabra. The structure was elucidated by spectroscopic methods. Our results indicated that 1 significantly inhibit nitric oxide (NO) production in LPS-induced RAW264.7 macrophages. RT-PCR analysis indicated it inhibited iNOS mRNA expression. In addition, Western blot analysis showed that 1 attenuated LPS-induced synthesis of iNOS protein in the macrophages. These results suggest that 1 could be potential anti-inflammatory agent by down-regulating iNOS expression.     

Abiesanordines A-N: fourteen new norditerpenes from Abies georgei

Fourteen new norditerpenoids (abiesanordines A-N, 1-14), including a novel podocarpene bearing a rare enolic structure (abiesanordine A, 1), were isolated from Abies georgei together with eight known ones. Their structures were determined mainly by detailed analysis of 1D and 2D NMR spectroscopic data including HSQC, DQF COSY, HMBC, and NOESY. All the isolates were tested for inhibitory activities against LPS-induced NO production in RAW264.7 macrophages, abiesanordine I (9) showed the strongest activity with the IC₅₀ value of 17.0 μg/mL. Furthermore, it exhibited no cytotoxicity against RAW264.7 macrophages under the concentration of 50 μg/mL.