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Abstract  

The cross-linked chitosan (CS) gels synthesized by using glutaraldehyde (GLA), epichlorohydrin (EC), and ethylene glycol diglycidyl ether (EGDE) as cross-linkers respectively were used to investigate the adsorption of U(VI) ions in an aqueous solution. The pure chitosan (PCS) and the cross-linked chitosan gels were characterized by FTIR and SEM analysis. The kinetic, thermodynamic adsorption and adsorption isotherms of U(VI) ions onto unmodified and modified cross-linked chitosan were studied in a batch adsorption experiments. The effect of pH, contact time and temperature on the adsorption capacity were also carried out. At the optimum pH, the maximum adsorbed amount of PCS, GLACS, ECCS and EGDECS were 483.05, 147.05, 344.83 and 67.56 mg/g, respectively. The uranium (VI) adsorption process of PCS and ECCS followed better with pseudo-second-order kinetic model, while GLACS and EGDECS followed pseudo-first-order kinetic model well. The results obtained from the equilibrium isotherms adsorption studied of U(VI) ions were analyzed in two adsorption models, namely, Langmuir and Freundlich isothms models, the results showed that the Langmuir isotherm had better conformity to the equilibrium data. The thermodynamic parameters such as enthalpy (ΔHº), entropy (ΔSº), and Gibbs free energy (ΔGº) showed that the adsorption process was both spontaneous and endothermic.

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Acta Biologica Hungarica
Authors:
Xiaoyan Liu
,
Md. Asaduzzaman Khan
,
Jingliang Cheng
,
Chunli Wei
,
Lianmei Zhang
, and
Junjiang Fu

Generation of the stable cell lines is a highly efficient tool in functional studies of certain genes or proteins, where the particular genes or proteins are inducibly expressed. The KRAB-associated protein-1 (KAP1) is an important transcription regulatory protein, which is investigated in several molecular biological studies. In this study, we have aimed to generate a stable cell line for inducing KAP1 expression. The recombinant plasmid pcDNA5/FRT/TO-KAP1 was constructed at first, which was then transfected into Flp-In™T-REx™-HEK293 cells to establish an inducible pcDNA5/FRT/TO-KAP1-HEK293 cell line. The Western blot analysis showed that the protein level of KAP1 is over-expressed in the established stable cell line by doxycycline induction, both dose and time dependently. Thus we have successfully established stable pcDNA5/FRT/TO-KAP1-HEK293 cell line, which can express KAP1 inducibly. This inducible cell line might be very useful for KAP1 functional studies.

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Abstract

Toddalia asiatica (Linn) Lam (T. asiatica) as a traditional Miao medicine was investigated to find rational alternative medicinal parts for T. asiatica root bark and its antitumor chemical constituents by quantitative pharmacognostic microscopy, high performance liquid chromatography (HPLC) fingerprint and multivariate statistical analysis. A bivariate correlation analysis method based on microscopic characteristics and content of chemical constituents was established for the first time, there were some regular discoveries between powder microscopic characteristics and common chromatographic peaks of T. asiatica through quantitative pharmacognostic microscopy, cork cells, calcium oxalate square crystal, brown clump, starch granule and phloem fiber, as powder microscopic characteristics may be placed where the main chemical constitutes were enriched. Scores plot of principal component analysis (PCA) and dendrogram of hierarchical clustering analysis (HCA) showed that 18 T. asiatica samples were distinguished correctly, clustered clearly into two main groups as follows: S01∼S03 (root bark) and S07∼S09 (stem bark) in cluster 1, S04∼S06 and S10∼S18 in cluster 2. Nineteen common peaks were obtained in HPLC fingerprint of T. asiatica, loadings plot of PCA indicated seven compounds played important roles in different part of samples (P10 > P08 > P07 > P14 > P16 > P17 > P19), peaks 04, 06, 07, 08, 10 were identified as hesperidin, 4-methoxycinnamic acid, toddalolactone, isopimpinlline and pimpinellin. MTT assay was used to determine the inhibitory activity of different medicinal parts of T. asiatica on human breast cancer MCF-7 cells, all parts of T. asiatica had different inhibitory effects on MCF-7 cell lines, root and stem barks of T. asiatica showed the best inhibitory activity. The relationship between chemical constituents and the inhibitions on MCF-7 cell had been established, significant antitumor constituents of T. asiatica were identified by correlation analysis, the order of the antitumor effect of the main compounds was P07 (toddalolactone) > P16 > P06 (4-methoxycinnamic acid), P11 > P18 > P10 (pimpinellin) > P08 (isopimpinellin) > P01 > P19 > P14 > P04 (hesperidin) > P17, which were antitumor chemical constituents of T. asiatica root bark. T. asiatica stem bark was the most rational alternative medicinal part for T. asiatica root bark.

Open access
Acta Chromatographica
Authors:
Xiaoyan Zhang
,
Jie Liu
,
Wenbo Sun
,
Xiangchun Shen
,
Xiaojian Gong
,
Cong Wang
,
Yan Liang
, and
Wei Zhou

Abstract

Natural hemostatic compounds from Toddalia asiatica (Linn) Lam (T. asiatica) root bark had been investigated by a novel strategy, chemical fingerprint–pharmacokinetic–pharmacodynamic (CF–PK–PD) for the first time in this study. The extract sample of T. asiatica root bark was subdivided into petroleum ether (PE), ethyl acetate (EA) and n-butanol (n-B) sample by reagent extraction, EA sample showed significant hemostatic activity using prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen (FIB) as evaluation indexes from rat plasma of PK experiment in hemorrhagic rat model. CF analysis was adopted to assist us to discover six natural compounds from T. asiatica root bark in actual rat plasma after sample treatment by Ultra Performance Liquid Chromatography-Electrospray Ionization (UPLC-ESI) MS, there were only lomatin and 5-methoxy-8-hydroxy psoralen showing significant hemostatic effect (P < 0.05) mainly through endogenous coagulation pathway and fibrinolytic system. In PK–PD study, six compounds in EA sample exhibited relatively rapid absorption and slow elimination characteristics. The mean T max and t 1/2β of isopimpinellin and pimpinellin were 1.74 and 0.59 h, 5.31 and 6.89 h in rats. On the basis of Sigmoid–E max model, PK–PD related curves of FIB in hemorrhagic rat model after treatment of T. asiatica root bark were obtained. Predicted E max, EC 50 and k e0 of FIB under isopimpinellin were 4.87 mg/mL, 1.39 μg/mL and 0.81 1/h; predicted E max, EC 50 and k e0 of FIB under pimpinellin were 4.29 mg/mL, 2.47 μg/mL and 0.77 1/h. In conclusion, hemostatic compounds from T. asiatica root bark had been materialized, there were lomatin, isopimpinellin, pimpinellin and 5-methoxy-8-hydroxy psoralen at least as its main active substances through coagulation pathways and fibrinolytic system. CF–PK–PD method as a promising method was worthy of follow-up opening, application in pharmaceutical research.

Open access

Abstract

Dendrobium nobile and Dendrobium officinale as the main varieties of traditional Chinese medicine Dendrobium are widely used in clinic. The study aimed to systematically explore chemical constituents and their antitumor effect of D. nobile and D. officinale by ultra-performance liquid chromatography coupled with ion trap time-of-flight mass spectrometry (UPLC-IT-TOF), network pharmacology and cancer cell experiments. D. nobile extract and D. officinale extract could significantly inhibit the proliferation of human lung cancer A549 cells, human liver cancer HepG2 cells and human breast cancer MCF-7 cells in the dose-dependent manner (P < 0.05), the antitumor effect of D. officinale extract was stronger than that of D. nobile extract at the same drug concentration. A total of 40 chemical constituents of D. nobile and D. officinale including phenanthrenes, bibenzyls and other types of compounds had been identified by UPLC-IT-TOF, LCMSsolution and MetID software according to retention times, accurate mass, MSn fragmentation, reference compounds and natural product databases. Phenanthrenes with good antitumor activity were mainly present in D. nobile, bibenzyls were the main compounds of D. officinale. Integrated networks of Herb-Compounds-Targets-Cancer revealed that gigantol, moscatilin, tristin, moscatin and densiflorol B were regarded as key antitumor compounds of D. nobile and D. officinale, D. nobile and D. officinale shared 7 targets accounting for 70% of the antitumor core targets, more than half of their antitumor KEGG pathways were similar. The results of molecular docking and western blotting experiments indicated that the antitumor mechanisms of D. nobile and D. officinale may be through inhibiting PI3K-Akt and HIF-1α signaling pathways.

Open access