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The leaf of the lotus (Nelumbo nucifera) is a natural plant resource used as both food and herbal medicine (He-Ye) in China. Alkaloids are considered the major bioactive compound of the herb and exhibit various biological activities, including anti-hyperlipidemia, anti-obesity, anti-inflammatory, and anti-hyperuricemic effects. Nuciferine (NF) and N-nuciferine (N-NF) are two major alkaloids found in the herb. In the present work, the plasma and brain pharmacokinetics of the two compounds were investigated after oral and intravenous (i.v.) administration of a lotus leaf alkaloid fraction to SD rats via ultra-performance liquid chromatography coupled with photodiode array detection and brain microdialysis. After oral administration (50 mg/kg), the two compounds NF and N-NF were rapidly absorbed into the blood and reached a mean maximum concentration (Cmax) of 1.71 μg/mL at 0.9 h and 0.57 μg/mL at 1.65 h, respectively. After i.v. administration (10 mg/kg), NF and N-NF were found to have a relatively wide volume of distribution (Vd, λz, 9.48 and 15.17 L/kg, respectively) and slow elimination half-life (t1/2, λz, 2.09 and 3.84 h, respectively). The oral bioavailability of NF and N-NF was estimated as 58.13% and 79.91%, respectively. After i.v. dosing (20 mg/kg), the two compounds rapidly crossed the blood–brain barrier and reached their Cmax (in unbound form): 0.32 and 0.16 μg/mL at 0.89 and 1.22 h, respectively. Both alkaloids had widespread distribution in the brain, with Vd, λz/F-values of 19.78 L/kg and 16.17 L/kg, respectively. The mean t1/2, λz values of NF and N-NF in the brain were 1.24 and 1.39 h, respectively. These results can help us to better understand the characteristics and neuro-pharmacological effects of the lotus alkaloid fraction.

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A synthetic hydroxyapatite coated porous alumina ocular orbital implant was developed by polymeric sponge method in order to overcome shortcoming of current coralline HA implant and to obtain secure attachment of extraocular muscles and fibrovascular in-growth. It allows porous alumina skeletal to be a load bearing member and synthetic HA coating layer to provide biocompatibility and long-term stability in an eye. It was found that slower heating rate of < 1°C/min at 280°C400°Cwas effective to achieve a dense porous alumina skeletal, and defects on as-sintered alumina skeletal was considerably decreased by the second coating of alumina slurry and sintering. The thickness of coated HA layer was about 20 µm with relatively good bonding to alumina skeletal. From in-vivo study, fibrovascularization was noted at periphery of the implant 2 weeks after implantation in all of the three groups, and to the center of the implant 4 and 12 weeks after implantation. This fibrovascularization was most predominant in 500 µm pore-sized group compared to the rest two groups. It is believed that HA coated porous alumina will be a good candidate for an artificial orbital implant with improved biocompatibility and long-term stability.