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Interaction mechanism and conformational change of model plasma protein - bovine serum albumin (BSA) induced by ferrocenyl-functionalized hyperbranched polyester (HBPE-Fc) were investigated using cyclicvoltammetry (CV), differential pulsed voltammetry (DPV), fluorescence, UV–vis absorption spectrometry and circular dichroism (CD). Some complicated interactions occurred between BSA and HBPE-Fc and the new redox centers appeared in the BSA/HBPE-Fc complex that changed and hindered the electron transfer of Fe/Fe 2+ . Fluorescence quenching data showed that the fluorescence of BSA was statically quenched by HBPE-Fc, which implied that ground state complex formed between BSA and HBPE-Fc. van der Waals force and hydrogen bond played major roles in the interaction of HBPE-Fc with BSA. The binding constant Ka for HBPE-Fc–protein interaction is in the order of 10 6 at room temperature indicates that there is a strong interaction between HBPE-Fc and BSA. Synchronous, three-dimensional fluorescence and CD studies indicated that the interaction of BSA with HBPE-Fc induced conformational changes in BSA with overall decrease in the α-helical structure and increase in β-pleated sheet structure. The molecular model of the interaction between HBPE-Fc and BSA was also presented according to the results in this study.

Mechanism of interaction between hyperbranched poly (amine) ester (HPAE) and bovine serum albumin (BSA) was investigated using fluorescence, synchronous fluorescence, three-dimensional fluorescence spectra, UV-Vis spectrometry and circular dichroism (CD). The structural and conformational changes of BSA induced by HPAE were also revealed in this study. Stern-Volmer analysis of fluorescence quenching showed that BSA fluorescence was statically quenched by HPAE, which implied that ground state complex formed between BSA and HPAE. Vander Waals force and hydrogen bond played major roles in the interaction of HPAE with BSA. The distance, r between the donor (BSA) and acceptor (HPAE) was calculated based on the Forster's theory of non-radiation energy transfer and was found to be 3.24 nm. Synchronous and three-dimensional fluorescence studies showed that the interaction of BSA with HPAE induced conformational changes in BSA. The secondary structural analysis by CD spectra suggested that HPAE binding induced BSA to form a more compact conformation with about 6.9% transformation of α-helix to β-sheet. Molecular model of the interaction of HPAE with BSA was also presented according to the results of this study.

Mechanism of interaction between ferrocenyl-functionalized hyperbranched poly(amine) ester (HPAE-Fc) and model plasma protein-bovine serum albumin (BSA) was investigated using cyclicvoltammetry, differential pulsed voltammetry, fluorescence, UV–Vis absorption spectrometry and circular dichroism (CD). Some complicated interactions occurred between BSA and HPAE-Fc and the new redox centers appeared in the BSA/HPAE-Fc complex that changed and hindered the electron transfer of Fe/Fe2+. Stern–Volmer analysis of fluorescence quenching data showed that BSA fluorescence was statically quenched by HPAE-Fc, which implied that ground state complex formed between BSA and HPAE-Fc. The hydrogen bonds and vander Waals force play major roles in the reaction as indicated by the 1H NMR and variable temperature 1H NMR spectra and thermodynamic parameters. The distance, r between the donor (BSA) and acceptor (HPAE-Fc) was calculated based on the Forster’s theory of non-radiation energy transfer and was found to be 3.24 nm, which in turn indicated that HPAE-Fc can bind to BSA with high probability. Synchronous, three-dimensional fluorescence and CD studies indicated that the interaction of BSA with HPAE-Fc induced conformational changes in BSA with overall decrease in the α-helical structure and increase in β-pleated sheet structure. The molecular model of the interaction between HPAE-Fc and BSA was also presented according to the results in this study.

Female sexual dysfunction (FSD) is a very common sexual health problem worldwide. The prevalence of FSD in Chinese women is, however, unknown. This is the first study to investigate a large number of young women throughout China via the internet, to determine the prevalence and types of FSD and to identify the risk factors for FSD.The primary endpoint was the Female Sexual Function Index (FSFI) score, with additional questions on contraception, sexual activity, relationship stability, pregnancy and other factors which may influence sexual function. The online questionnaire was completed by women from 31 of the 34 Chinese provinces.A total of 1618 completed questionnaires were received, and 1010 were included in the analyses after screening (62.4%). The mean age of the respondents was 25.1 ± 4.5 years. The mean total FSFI score was 24.99 ± 4.60. According to FSFI definitions (cut-off score 26.55), 60.2% of women were at risk of FSD. Based on domain scores, 52 were considered at high risk of dysfunction for pain (5.1%), 35 for orgasm (3.5%), 33 for desire (3.3%), 20 for arousal (2.0%), 6 for satisfaction (0.6%) and 2 for lubrication (0.2%).The prevalence of FSFI scores indicating risk of sexual dysfunction was about 60% in Chinese women. An unstable relationship, pressure to become pregnant, non-use of contraception, negative self-evaluation of appearance and increasing age were significantly associated with FSD in young Chinese women.

In order to improve the interfacial bonding strength of hydroxyapatite/polyurethane implanted material and dispersion of hydroxyapatite in the polyurethane matrix, we in the present study synthesized nano-hydroxyapatite/polyurethane composites by in situ polymerization. We then characterized and analyzed the fracture morphology, thermal stability, glass transition temperature and mechanical properties. We seeded MG63 cells on composites to evaluate the cytocompatibility of the composites. In situ polymerization could improve the interfacial bonding strength, ameliorate dispersion of hydroxyapatite in the properties of the composites. After adding 20 wt% hydroxyapatite into the polyurethane, the thermal stability was improved and the glass transition temperatures were increased. The tensile strength and maximum elongation were 6.83 MPa and 861.17%, respectively. Compared with those of pure polyurethane the tensile strength and maximum elongation increased by 236.45% and 143.30%, respectively. The composites were helpful for cell adhesion and proliferation in cultivation.