Comparative evaluation of polysaccharides isolated from Astragalus, oyster mushroom, and yacon as inhibitors of α-glucosidase / 中国天然药物

The incidence of diabetes has increased considerably, and become the third serious chronic disease following cancer and cardiovascular diseases. Though acarbose, metformin, and 1-deoxynojirimycin have good efficacy for clinical application as hypoglycemic drugs, their expensive costs and some degree of side effects have limited their clinical application. Recently, increasing attention has concentrated on the polysaccharides from natural plant and animal sources for diabetes. In order to illustrate the pharmaceutical activity of polysaccharides as natural hypoglycemic agents, polysaccharides isolated from Astragalus, oyster mushroom, and Yacon were evaluated for their inhibitory effects on α-glucosidase. Polysaccharides were extracted and purified from Astragalus, Oyster mushroom, and Yacon with hot water at 90 °C for 3 h, respectively. The total sugar content of the polysaccharide was determined by the phenol-sulfuric acid method. The α-glucosidase inhibitory activity was measured by the glucose oxidase method. The results exhibited that the inhibitory effects on α-glucosidase were in decreasing order, Astragalus > oyster mushroom > Yacon. The α-glucosidase inhibition percentage of Astragalus polysaccharide and oyster mushroom polysaccharide were over 40% at the polysaccharide concentration of 0.4 mg·mL(-1). The IC50 of Astragalus polysaccharide and oyster mushroom polysaccharide were 0.28 and 0.424 mg·mL(-1), respectively. The information obtained from this work is beneficial for the use polysaccharides as a dietary supplement for health foods and therapeutics for diabetes.

Long-term effect and safety of non-occlusive intra-vas device for male contraception / 中华男科学杂志

<p><b>OBJECTIVE</b>To assess the long-term effect and safety of non-occlusive intra-vas device (IVD) for male contraception in comparison with no-scalpel vasectomy (NSV).</p><p><b>METHODS</b>We conducted a follow-up investigation on 100 males who had received IVD and another 50 who had undergone NSV 6 years before. We compared the rates of sperm absence and complications between the two groups.</p><p><b>RESULTS</b>Follow-up visits were successfully performed on 95 males (95%) of the IVD group and 44 (88%) of the NSV group. Pregnancy was not found in any of the cases. Spermatozoa (> or = 5 x 10(6)/ml) were not detected in 87 cases (91.58%) in the IVD group and in 44 cases (95.45%) in the NSV group, with no significant differences between the two groups (P > 0.05). The rate of postoperative complications in the IVD group (11.58%) showed no significant difference from that of the NSV group (4.55%) (P > 0.05).</p><p><b>CONCLUSION</b>IVD is as effective and safe as NSV for male contraception.</p>

N-acetylcysteine and Taurine inhibit hyperoxia-induced cataract in rabbit lens / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the efficacy of N-acetylcysteine (NAC) and taurine (Tau) in preventing hyperoxia-induced the lens opacification and the changes of biochemical parameters on organ cultured rabbit lenses.METHODS: Twenty-four lenses from adult rabbits were divided into the control group, the hyperoxia-exposed group, the hyperoxia-exposed group containing 20mmol/L of NAC, the hyperoxia-exposed group containing 80mmol/L of Tau, respectively. The treated groups incubated with hyperoxia ( pO2>80%) for 4 hours per day throughout a 7-day period. Lens transparency, histology and enzymatic activities measurements were determined after this incubation.RESULTS: Gross morphological examination of these lenses revealed some severe cortical opacification in the hyperoxia-exposed group, moderate cortical opacification in the control group and the Tau treated group. There was minimal cortical opacification in the NAC treated group. The glutathione (GSH) content and the activity of Na, K-ATPase were significantly decreased in the hyperoxia-exposed group than that of the control group, by 37.8% (P<0.05) and 53.5% (P<0.05), respectively. However, they were increased in the two treated groups, especially in the NAC treated group. There were no significant differences in the water-soluble protein content and the catalase and GSH reductase activities in all group lenses.CONCLUSION: Hyperoxia can induce the cortical opaci-fication in the lens. The role of NAC in the prevention of hyperoxia-induced cataract is superior to Tau.