Beneficial effects of green tea (Camellia sinensis, Theaceae) extracts against obesity have been reported; however, the anti-obesity ability of the major components of green tea, polysaccharides, polyphenols and caffeine is not clear. Therefore, experiments with total green tea extracts, polyphenols, polysaccharides, caffeine, and a complex of polysaccharide and polyphenol at a dose of 400 or 800 mg kg⁻¹ were conducted on high-fat diet fed rats for 6 weeks to investigate their anti-obesity effects. The results indicated that polyphenols and polysaccharides were responsible for the suppressive effect of green tea extracts on body weight increase and fat accumulation. Moreover, polyphenols, polysaccharides, or caffeine can improve blood lipid and antioxidant levels, and effectively reduce rat serum leptin levels, inhibit the absorption of fatty acids, and markedly reduce the expression levels of the IL-6 and TNF-α gene. Furthermore, it was shown that polysaccharides and polyphenols were synergistic in reduction of serum leptin levels and in anti-inflammatory activity. These results suggest that the polysaccharide combination with polyphenols might be a potential therapy against obesity.

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In this study, bivariate hydrologic risk analysis was conducted based on the daily streamflow discharge at the Xianyang station on the Wei River. This bivariate hydrologic risk analysis was conducted based on copula methods, in which the bivariate hydrologic frequency was firstly quantified through copulas, and the bivariate hydrologic risk analysis was then characterized based on the joint return period of flood pairs. The maximum likelihood estimation (MLE) and the method-of-moments-like (MOM) estimator were compared in estimating the unknown parameters in copula. The results showed that the GumbelHougaard copula was most appropriate for modelling the dependence for all three flood pairs, in which the parameter of the copula for flood peak-volume was estimated by MLE and the parameters of the copulas for flood peak-duration and volume-duration were needed to be obtained by MOM. The bivariate hydrologic risk values are then obtained based on the AND-joint return period. The results show that the bivariate hydrologic values will not decrease until the corresponding volume for a flood is larger than 1.0 9 10 4 m 3 /s. For the bivariate hydrologic risk for flood peak-duration, the value will decrease quickly when the duration is longer than 5 days. Such bivariate hydrologic risk analysis can provide decision support for hydraulic facility design as well as actual flood control and mitigation.

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Nav1. 9 voltage-gated sodium channel is preferentially expressed in peripheral nociceptive neurons. Recent progresses have proved its role in pain sensation, but our understanding of Nav1.9, in general, has lagged behind because of limitations in heterologous expression in mammal cells. In this work, functional expression of human Nav1.9 (hNav1.9) was achieved by fusing GFP to the C-terminal of hNav1.9 in ND7/23 cells, which has been proved to be a reliable method to the electrophysiological and pharmacological studies of hNav1.9. By using the hNav1.9 expression system, we investigated the electrophysiological properties of four mutations of hNav1.9 (K419N, A582T, A842P, and F1689L), whose electrophysiological functions have not been determined yet. The four mutations significantly caused positive shift of the steady-state fast inactivation and therefore increased hNav1.9 activity, consistent with the phenotype of painful peripheral neuropathy. Meanwhile, the effects of inflammatory mediators on hNav1.9 were also investigated. Impressively, histamine was found for the first time to enhance hNav1.9 activity, indicating its vital role in hNav1.9 modulating inflammatory pain. Taken together, our research provided a useful platform for hNav1.9 studies and new insight into mechanism of hNav1.9 linking to pain.