[Binding interaction of harpagoside and bovine serum albumin: spectroscopic methodologies and molecular docking].

Scrophularia ningpoensis has exhibited a variety of biological activities and been used as a pharmaceutical product for the treatment of inflammatory ailment, rheumatoid arthritis, osteoarthritis and so on. Harpagoside (HAR) is considerer as a main bioactive compound in this plant. Serum albumin has important physiological roles in transportation, distribution and metabolism of many endogenous and exogenous substances in body. It is of great significance to study the interaction mechanism between HAR and bovine serum albumin (BSA). The mechanism of interaction between HAR and BSA was investigated using 2D and 3D fluorescence, synchronous florescence, ultraviolet spectroscopy and molecular docking. According to the analysis of fluorescence spectra, HAR could strongly quench the fluorescence of BSA, and the static quenching process indicated that the decrease in the quenching constant was observed with the increase in temperature. The magnitude of binding constants (KA) was more than 1×105 L·mol⁻¹, and the number of binding sites(n) was approximate to 1. The thermodynamic parameters were calculated through analysis of fluorescence data with Stern-Volmer and Van't Hoff equation. The calculated enthalpy change (ΔH) and entropy change (ΔS) implied that the main interaction forces of HAR with BSA were the bonding interaction between van der Waals forces and hydrogen. The negative values of energy (ΔG) demonstrated that the binding of HAR with BSA was a spontaneous and exothermic process. The binding distance(r) between HAR and BSA was calculated to be about 2.80 nm based on the theory of Frster's non-radiation energy transfer, which indicated that energy is likely to be transfer from BSA to HAR. Both synchronous and 3D florescence spectroscopy clearly revealed that the microenvironment and conformation of BSA changed during the binding interaction between HAR and BSA. The molecular docking analysis revealed HAR is more inclined to BSA and human serum albumin (HSA) in subdomain ⅡA (Sudlow's site I). This study will provide valuable information for understanding the action mechanism of HAR.

[An epidemiological study on domestic violence in Hunan, China].

OBJECTIVE: To investigate the prevalence of domestic violence (DV) in Hunan. METHODS: Using a multi-stage sampling strategy, 9451 households involving 32 720 persons in urban, rural and industrial areas in Hunan, China were studied. Multiform clue investigation and face-to-face interviews were combined to investigate the prevalence of DV. RESULTS: A lifetime prevalence of DV was reported by 1533 households (16.2%). A total of 1098 households (11.6%) reported at least one incident of DV in the previous year. Both lifetime and 12-month prevalence of DV varied significantly by geographic setting (P < 0.01). The lifetime prevalence abuse rates were: spousal 10.2%, child abuse 7.8%, and elder 1.5%. With regard to household structure, the lifetime prevalence of DV was highest among those remarried families (21.0%), followed by married couples with one child and extended families with several generations living together (20.1% and 20.0%, respectively). The highest rate of spousal abuse was found among remarried families (14.7%), while child and elder abuse was most prevalent among extended families (12.4% and 4.1%, respectively). CONCLUSIONS: The findings suggested that although the prevalence of DV in Hunan was modest compared to Western countries, it remained a serious public health problem affecting over 1 in 10 households. Furthermore, the prevalence of various types of DV varied by geographic setting and family structure, suggesting that diverse geographic setting and family constellations carried different risk and protective features.