Robust half-metallic ferromagnetism and curvature dependent magnetic coupling in fluorinated boron nitride nanotubes.

The fluorinated boron nitride (F-BN) nanostructures are found to be fully spin polarized and half-metallic by means of first-principles calculations based on the Heyd-Scuseria-Ernzerhof hybrid functional. It is found that the full spin polarization and 1 µB local moment in F-BN nanotubes are independent of tube radius and it is also robust in planar ribbons and sheets. The long-ranged ferromagnetic coupling between local moments decreases with decreasing tube radius. This suggests that F-BN systems with small local curvatures could be more easily experimentally observed and have greater potential applications in spin devices.

[Protection of polysaccharides-2b from mudan cortex of Paeonia suffruticosa andr on diabetic cataract in rats].

OBJECTIVE: To observe the the protective effection of polysaccharides-2b of mudan cortex of Paeonia suffruticosa andr (PSM2b) on diabetic cataract. METHOD: The animal model of diabetic cataract in rats was induced by streptozotocin (STZ) and freund's adjuvant complete (CFA). The initial opacity occurrence time in lens was investigated with cranny lamp, and opacity degree of lens was compared too. The activities of glutathione peroxidase (GSH-pX), superoxide dismutase (SOD), catalase (CAT), the content of malonaldehyde (MDA) in serum and lens were detected. At the same time, the activities of Na(+) -K(+) -ATPase, the content of macromolecular weight protein and infusibility protein in lens were detected too. RESULT: The results examinated by cranny lamp showed that PSM2b could significantly postpone the occurrence and alleviate opacity degree of lens. Compared with model group, every treatment group of PSM2b could lower the level of MDA, high and middle dose groups could increase the levels of SOD, GSH-pX, CAT in serum and lens in evidence, and enhance the activity of Na(+) -K(+) -ATPase. These indexes present favorable positive correlation between dose and effect. CONCLUSION: All these results demonstrated that PSM2b had apparently protective effection on diabetic cataract in rats.

[Protection of polysaccharide ATPS-2 from Armillariella tabescens on immunological liver injury in mice induced by BCG plus LPS].

OBJECTIVE: To observe the effect of polysaccharide ATPS-2 from Armillariella tabescens on the immunological liver injury in mice induced by BCG plus LPS. METHOD: BCG and LPS were adopted to establish BCG plus LPS liver injury model in mice. The content of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and NO, the activity of superoxide dismutase (SOD) and malondiadehyde (MDA) content of liver homogenate in mice were measured by colorimetric method. The content of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), on serum were measured by enzyme linked immunosorbent assay (ELISA) , and T- and B-lymphocyte proliferation were measured by MTT. Index of liver, spleen and thymus were calculated after treatment. RESULT: Polysaccharide ATPS-2 from A. tabescens (25, 50, 100 mg x kg(-1)) could obviously reduce the high level of ALT, AST, NO and TNF-alpha, IL-1 on serum, inhibit the high level of MDA, increase the low activity of SOD in liver homogenate and enhance T-and B-lymphocyte proliferation, elevate the spleen, thymic index and decrease liver index of the mice to different extent. CONCLUSION: Polysaccharide ATPS-2 from A. tabescens had apparently protective effects in the immunological liver injury mice induced by BCG plus LPS.