[Preparation of Oenothera biennis Oil Solid Lipid Nanoparticles Based on Microemulsion Technique].

OBJECTIVE: To study the preparation of Oenothera biennis oil solid lipid nanoparticles and its quality evaluation. METHODS: The solid lipid nanoparticles were prepared by microemulsion technique. The optimum condition was performed based on the orthogonal design to examine the entrapment efficiency, the mean diameter of the particles and so on. RESULTS: The optimal preparation of Oenothera biennis oil solid lipid nanoparticles was as follows: Oenothera biennis dosage 300 mg, glycerol monostearate-Oenothera biennis (2: 3), Oenothera biennis -RH/40/PEG-400 (1: 2), RH-40/PEG-400 (1: 2). The resulting nanoparticles average encapsulation efficiency was (89.89 ± 0.71)%, the average particle size was 44.43 ± 0.08 nm, and the Zeta potential was 64.72 ± 1.24 mV. CONCLUSION: The preparation process is simple, stable and feasible.

Polydisulfide manganese(II) complexes as non-gadolinium biodegradable macromolecular MRI contrast agents.

PURPOSE: To develop safe and effective manganese(II) -based biodegradable macromolecular MRI contrast agents. MATERIALS AND METHODS: In this study, we synthesized and characterized two polydisulfide manganese(II) complexes, Mn-DTPA cystamine copolymers and Mn-EDTA cystamine copolymers, as new biodegradable macromolecular MRI contrast agents. The contrast enhancement of the two manganese-based contrast agents were evaluated in mice bearing MDA-MB-231 human breast carcinoma xenografts, in comparison with MnCl(2) . RESULTS: The T(1) and T(2) relaxivities were 4.74 and 10.38 mM(-1) s(-1) per manganese at 3T for Mn-DTPA cystamine copolymers (M(n) = 30.50 kDa) and 6.41 and 9.72 mM(-1) s(-1) for Mn-EDTA cystamine copolymers (M(n) = 61.80 kDa). Both polydisulfide Mn(II) complexes showed significant liver, myocardium and tumor enhancement. CONCLUSION: The manganese-based polydisulfide contrast agents have a potential to be developed as alternative non-gadolinium contrast agents for MR cancer and myocardium imaging.

[Preparation and authentication of beta-cyclodextrin complex of volatile oil from Ledum palustre].

OBJECTIVE: To study the optimum inclusion process conditions for the beta-cyclodextrin complex of volatile oil from Ledum palustre. METHODS: The utilization ratio of the volatile oil from Ledum palustre was set as the index, and four factors were selected including the ratio of the volatile oil to beta-cyclodextrin, the temperature of preparation, the inclusion time and the ratio of beta-cyclodextrin to water. The optimum conditions were investigated by the orthogonal test form L9 (3(4)). The inclusion compound was identified by the ways of Micro-imaging, Thin-layer chromatography (TLC), Ultraviolet Spectroscopy (UV)and Infrared Spectroscopy (IR). RESULTS: The optimum preparation conditions were as follows: volatile oils: beta-cyclodextrin was 1:8, the inclusion temperature and time was 50 degrees C and 30 min, respectively. Beta-cyclodextrin: water was 1:15. CONCLUSION: The inclusion technology is stable and its quality is adjustable.

Reduction of serotonin content by tetrahydropapaveroline in murine mastocytoma P815 cells.

The inhibitory effects of tetrahydropapaveroline on serotonin biosynthesis in serotonin-producing murine mastocytoma P815 cells were investigated. Tetrahydropapaveroline decreased serotonin content in a concentration-dependent manner in P815 cells and showed 44.9% reduction of serotonin content at a concentration of 5.0 microM for 24 h. The value of 50% inhibitory concentration, IC(50), of tetrahydropapaveroline was 7.5 microM. Under these conditions, tryptophan hydroxylase (EC 1.14.16.4, TPH) was inhibited for 24-36 h after treatment with tetrahydropapaveroline in P815 cells (46.6% inhibition at 7.5 microM). In addition, tetrahydropapaveroline inhibited the activity of TPH, prepared from the P815 cells (P815-TPH), with the IC(50) value of 8.4 microM. Inhibition of P815-TPH by tetrahydropapaveroline was found to be non-competitive both with the substrate L-tryptophan and with the cofactor DL-6-methyl-5,6,7,8-tetrahydropterine. The K(i) value of tetrahydropapaveroline with L-tryptophan was 9.29 microM. These data indicate that tetrahydropapaveroline leads to a decrease in serotonin content by inhibiting TPH activity in P815 cells.