[In vivo intestinal absorption characteristics of phloridzin in rats].

To study the in vivo intestinal absorption kinetics of phloridzin in rats. The absorption of phloridzin in the small intestines and colon of rats was investigated using an in vivo single-pass perfusion method and the drug concentration was measured by HPLC. The effects on intestinal absorption of different drug concentration and P-glycoprotein (P-gp) inhibitor were conducted. The results showed that the phloridzin could be absorbed in whole intestine, but more fully in the jejunum and colon segment,poorly absorbed in the duodenum and ileum. The absorption rate constant (Ka) and the apparent absorption coefficient（Papp）of phloridzin decreased following the sequence of jejunum> colon > duodenum > ileum. Absorption parameters of phloridzin had no significant difference at different concentration (5.14, 10.28, 20.56 mg•L⁻¹) . The saturate phenomena was not observed under the test range of drug concentration, and the absorption mechanism may be the passive diffusion transport.There had a significant difference in Ka and Papp values between P-gp inhibitor and no P-gp inhibitor groups. Phloridzin may be the substrate of P-gp.

[Optimization on Preparation of Total Saponins of Aralia taibaiensis Phospholipid Complex by Central Composite Design-Response Surface Method].

Objective: To optimize the preparation of total saponins of Aralia taibaiensis phospholipid complex( TSAT-PC) by the central composite design-response surface method. Methods: Total saponins of Aralia taibaiensis phospholipid complex was prepared by using solvent evaporation method, five factors including reaction solvent, reaction time, reaction temperature, ratio of reactants on this reaction, and the concentration of the drug were investigated, then to optimize the preparation of TSAT-PC by the central composite design response surface method, and to study its physicochemical properties. Results: The optimal process conditions were as follows, the reaction time was 1 h, the reaction temperature was 45 ℃,the ratio of soya lecithine ( SL) and TSAT was 3∶ 1, the reaction concentration was16 mg / m L, the complexing rate was 97. 23%,it was less than 5% with the predicted deviation; IR analysis proved the formation of TSAT-PC, and the solubility in the octyl alcohol was higher than the original drug. Conclusion: TSAT-PC was successfully developed by the optimized process, enhance the solubility in octyl alcohol, which provide the reference for the further development and utilization of Chinese materia medica preparation.

Radiobiological effect induced by different activities of (125)I seed brachytherapy in a hepatocellular carcinoma model.

BACKGROUND: Iodine 125 ((125)I) seed irradiation is an effective non-surgical treatment for unresectable hepatocellular carcinoma (HCC) patients. However, the safety and tolerability of (125)I seed sequential irradiation therapy remain unclear, there is no unified standard of brachytherapy radiation dose, and further study on the basic radiobiology of continuous rate irradiation is necessary. METHODS: Forty Kunming-mice (KM-mice, China) were injected with suspensions of human hepatocellular carcinoma cells (H22) to create an animal model and mimic (125)I seed implantation. The survival rates of mice, curative effect, pathological impairments including apoptosis and necrosis were investigated. The mice were randomly divided into four groups, A, B, C and D. In group A, 0.78 mCi (125)I seeds were implanted into the tumor focus. In groups B and C, 0.58 mCi and 0.38 mCi (125)I seeds were inserted at the same location, respectively. Group D was a control group, without any treatment. After 28 days of therapy, the survival rates and the tumor size were measured, and pathological impairments was measured by light or electron microscopy. RESULTS: The tumor volume inhibition rate was 68.21% ± 3.21%, 51.38% ± 4.96%, and 35.71% ± 2.79% after 0.78 mCi, 0.58 mCi, and 0.38 mCi (125)I seeds irradiation, respectively. However, radiation-related side effects were also observed in the high-dose group. Pathological results showed that radiation effect was closely associated with radiation dose, as the increase of radiation dose, an increase in apoptosis and necrosis was detected. Significant cellular impairments were noted by pathological analysis under electron microscopy. CONCLUSIONS: Our results demonstrate that the Kunming-mouse is an ideal animal to study (125)I brachytherapy, and the curative effect was closely associated with radiation dose. High-dose of brachytherapy may effectively increase apoptosis and necrosis in liver cells in KM-mice. A dose of 0.58 mCi (125)I radioactive particles may be a safe, effective and minimally invasive therapeutic option for liver cancer.