Research progress on chemistry and bioactivity of isopentenyl flavonoids from Sophora flavescens / 中国临床药理学与治疗学

Isopentenyl flavonoids are a class of characteristic components in Sophora flavescens Ait. (S. flavescens). They have biological activities such as anti-tumor, anti-bacteria, anti-inflammol/ Lation and anti-oxidation. In this paper, the structural types, toxicology and pharmacological effects of isopentenyl flavonoids from S. flavescens were briefly reviewed. Furthermore, the worth of further study on pharmacokinetics, pharmacodynamics, toxicology, action targets, molecular mechanisms and structure-function relationships of isopentenyl flavonoids were proposed. The deep exploration on functional characterastics of isopentenyl flavonoids of S. flavescens and their application on development of innovative drugs are of great significance to further improve the added value of isopentenyl flavonoids and expand their application fields.

Ultraviolet Spectroscopy Combined with Chemometrics for Simultaneous Quantitative Determination of 2,4,6-Trinitrotoluene andIts Degraded Products in Environmental Water Sample / 分析化学

2,4,6-Trinitrotoluene (TNT) and its by-products dinitrotoluene (DNT) pose a significant threat to human health and other living organisms.However, the conventional analytical methods involved in bulky and expensive instruments are complicated and time-consuming, impeding quick and on-line determination.In this work, a facile yet effective strategy of utilizing UV-vis spectroscopy coupled with partial least squares (PLS) was proposed, through which TNT and two isomers of DNT (2,4-DNT and 2,6-DNT) in nature water could be rapidly and simultaneously determined without any pre-separation.Variable combination population analysis (VCPA) was utilized to select important feather variables and significantly improved the predictive performance of the PLS model.The calibration set contained 25 samples constructed by orthogonal array design (OAD).The predictive ability of the models was validated by an independent prediction set including 15 samples, achieving up to 0.99 of the determination coefficients (R2) for each of the analytes.The optimized models were successfully applied to determine the 3 ingredients in 8 environmental samples involving in tap, lake and two kinds of river water with the recovery values of great than 97%.Finally, the proposed method was further validated by high performance liquid chromatography method.UV-vis spectroscopy coupled with chemometrics may be used as simple and effective strategy with high potential in environmental monitoring.

A Combination of Molecular Simulation and Network Methods for Analysis of Conformation Variation in Activation Process of β2 Adrenergic Receptor / 分析化学

To fill the urgent need of researches on the structure and function of proteins to obtain conformation information, we combined targeted molecular dynamics ( TMD) simulation with protein network methods to analyze conformation variations in the activation process of β2 adrenergic receptor. First, targeted MD was used to obtain the conformation resembles in the activation process, and then the protein network method was applied to identify the key residues and pathways in the activation process. The results indicate that the activa-tion process of β2 adrenergic receptor involves in the cooperation of all regions and the connector region of transmembrane helices is signaling hubs. In addition, the helix ends, including intracellular and extracellular loops, are the core areas. The pathway analysis reveals that there is more than one signaling pathway. All the pathways start from Ser204 of the ligand pocket and finally transmit to NPxxY or ICL2 region, which are depended on the different pathways. While the helix TMIII, TMV, TMVI are the important areas in all the pathways. The observations from the work provide valuable information at molecular level for unraveling the signal transduction mechanism associated with the activation process.