A new triterpenoid glycoside（l） and seven known triterpenoid glycosides, pseudoginsenoside RT2（2）,yesanchinoside R2（3）, vinaginsenoside R13（4）, vinaginsenoside R8（5）, notoginsenoside E（6）, 6＂＇-O-acetylgi...
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A new triterpenoid glycoside（l） and seven known triterpenoid glycosides, pseudoginsenoside RT2（2）,yesanchinoside R2（3）, vinaginsenoside R13（4）, vinaginsenoside R8（5）, notoginsenoside E（6）, 6＂＇-O-acetylginsenosideRe（7）, 6＂-O-acetylginsenoside Rbl（8）, were isolated from the rhizomes of Panaeis maforis. The new triterpenoidglycoside was elucidated as 3-O-[β-D-glucopyranosyl-（l→2）-fl-D-（6＇-O-ethyl）-glucuronopyranosyl]-oleanolicacid-28-O-β-D-glucopyranoside by extensive spectroscopic and phytochemical methods. Compounds 2-8 wereobtained from the plant for the first time. Compounds 3 and 4 displayed good activities against adenosine diphosphate（ADP）-induced platelet aggregation, and compounds 1, 5, 6 and 8 showed moderate activities. Compound 6 exhibitedmoderate antiplatelet aggregation activity induced by arachidonic acid（AA）.
A simple and sensitive method for determination of three aconitum alkaloids and their metabolites in human plasma was developed using matrix solid-phase dispersion combined with vortex-assisted dispersive liquid-liqui...
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A simple and sensitive method for determination of three aconitum alkaloids and their metabolites in human plasma was developed using matrix solid-phase dispersion combined with vortex-assisted dispersive liquid-liquid microextraction and high-performance liquid chromatography with diode array detection. The plasma sample was directly purified by matrix solid-phase dispersion and the eluate obtained was concentrated and further clarified by vortex-assisted dispersive liquid-liquid microextraction. Some important parameters affecting the extraction efficiency, such as type and amount of dispersing sorbent, type and volume of elution solvent, type and volume of extraction solvent, salt concentration as well as sample solution pH, were investigated in detail. Under optimal conditions, the proposed method has good repeatability and reproducibility with intraday and interday relative standard deviations lower than 5.44 and 5.75%, respectively. The recoveries of the aconitum alkaloids ranged from 73.81 to 101.82%, and the detection limits were achieved within the range of 1.6-2.1 ng/mL. The proposed method offered the advantages of good applicability, sensitivity, simplicity, and feasibility, which makes it suitable for the determination of trace amounts of aconitum alkaloids in human plasma samples.
A green and effective extraction system based on the use of an ultrasound-assisted ionic liquid aqueous two-phase system (IL-ATPS) was developed for the determination of aconitum alkaloids in lateral roots of Aconitum...
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A green and effective extraction system based on the use of an ultrasound-assisted ionic liquid aqueous two-phase system (IL-ATPS) was developed for the determination of aconitum alkaloids in lateral roots of Aconitum carmichaeli Debx (Fuzi in Chinese). IL-ATPS parameters, including the type and amount of ionic liquid, amount of salts, and pH value, as well as extraction time, were investigated. Under the optimized conditions, the recoveries of the analytes varied from 80.37 to 107.18%. The detection limits and quantification limits for the analytes were achieved within the ranges of 0.048-0.082 mg g(-1) and 0.16-0.30 mg g(-1), respectively. After extraction, the recovery of ionic liquids without the use of organic solvents was also confirmed. The hydrophilic ionic liquids (1-hexyl-3-methylimidazolium bromide) were converted into hydrophobic ionic liquids (1-hexyl-3-methylimidazolium hexafluorophosphate) by a metathesis reaction, and in situ liquid-liquid microextraction was triggered simultaneously. Finally, 0.1 mol L-1 HCl aqueous solution (containing 5% Tween-20) was used as the back-extraction agent to recover the ionic liquids.
G protein-coupled receptor, family C, group 5, member A (GPRC5A) had received attentions for its role in carcinogenesis and prognostic values in several types of cancer. However, the functional roles of GPRC5A in gast...
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G protein-coupled receptor, family C, group 5, member A (GPRC5A) had received attentions for its role in carcinogenesis and prognostic values in several types of cancer. However, the functional roles of GPRC5A in gastric cancer (GC) had never been elucidated. The expression levels of GPRC5A were detected by real-time quantitative reverse transcription PCR and Western blot in GC tissues and adjacent non-tumor tissues. GPRC5A expression in tissue sections of 106 GC samples was evaluated using immunohistochemistry. The staining results were compared with clinicopathological factors and to the prognosis of GC patients. The mRNA and protein expression levels of GPRC5A in gastric cancer tissues were higher than those in adjacent non-tumor tissues. Positive GPRC5A expression was significantly correlated with larger size of primary tumor, diffuse type (Lauren's classification), deeper serosal invasion, and more lymph node metastasis. In addition, Kaplan-Meier curve analysis demonstrated that GC patients with positive GPRC5A expression had poor prognosis than those with negative GPRC5A expression. GPRC5A expression was identified as an independent factor of the overall survival in GC patients by multivariate Cox analysis. Further, the overall survival difference existed between patients with GPRC5A positive and negative groups in GC patients with lymph node metastasis. Our results suggested that elevated levels of GPRC5A played significant roles in GC progression. GPRC5A could serve as a prognostic biomarker of GC.
Silica and graphene oxide (GO) were synthesized by modified Stober and Hummer's methods, respectively. Silica/GO composite powders of different compositions were obtained by introduction of GO sheets in between si...
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Silica and graphene oxide (GO) were synthesized by modified Stober and Hummer's methods, respectively. Silica/GO composite powders of different compositions were obtained by introduction of GO sheets in between silica particles through a hydrothermal synthesis. Composites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction analysis, and scanning and transmission electron microscopy. Density measurements were performed with a pycnometer and chemical analyses of powders were performed by energy-dispersive X-ray and X-ray photoelectron spectroscopies. Composite powders showed an improvement in the Cu2+ ion adsorption property relative to pure silica. Composite powders were further consolidated at 1200 degrees C under 50MPa pressure in vacuum by pulsed electric current sintering. Transparency in the UV/Vis region, the electrical conductivity, and the toughness of consolidated samples were altered by varying the GO content in the starting materials. Studies suggest that the use of GO as a reinforcing agent not only improves the mechanical properties of transparent silica ceramic, but also improves the electrical conductivity and adsorption properties of silica.
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