Preparation of lyophilized powder in oral Pueraria flavonoids loaded solid lipid nanoparticles and determination of release rate of its four effective components / 中草药

Objective: To prepare the lyophilized powder of Pueraria flavonoids loaded solid lipid nanoparticles (PF-SLN) and determine the dissolution rate of its four effective components: 3'-hydroxypuerarin, puerarin, daidzin, and daidzein. Methods: PF-SLN was prepared by the high pressure homogenization (HPH) technology. The lyophilized formula contained mannitol as cryoprotectant. The release rates of the four effective components from the PF-SLN lyophilized powder as well as the physical mixture were determined, with artificial gastric juice (pH 1.2) as dissolvent. Results: The technical parameters of PF-SLN preparation optimized by orthogonal test were as follows: The ratio and the dosage of lipid-surfactant were 2:1 and 2.0%, PF dosage was 2.5%, and 150 MPa homogeneity was 15 cycles. The optimal PF-SLN lyophilized powder was loosen with the particle size of (517.1 ± 10.3) nm, polydisperse index of 0.484 ± 0.210, and Zeta potential of (-21.91 ± 2.03) mV, respectively. The in vitro accumulated dissolution rates of PF-SLN lyophilized powder were slower than those of the physical mixture. Conclusion: The method employed to prepare PF-SLN lyophilized powder is feasible. PF-SLN lyophilized powder could delay the in vitro dissolution rate notablely. It might be a novel vehicle potentially for nano-drug delivery system of Pueraria flavonoids.

Protective effect of mouse 2.5s nerve growth factor on PC12 cells from injury induced by 2, 5-hexanedione / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore whether the nerve growth factor has protective effects on PC12 cells from injury induced by 2, 5-hexanedione.</p><p><b>METHODS</b>With PC12 cells as the model of neurons, different concentrations of NGF were added into the culture of PC12 cells. Then cell viability was tested with MTT. The DNA fragment was observed with agarose gel electrophoresis. The apoptosis ratio was tested with flow cytometry (FACS). The p53 protein was detected with western blot. The differences among the groups were compared.</p><p><b>RESULTS</b>Cell viabilities were increased with the increase of the concentrations of NGF (P < 0.05). The DNA fragment, the apoptosis ratio and the expression of p53 were all decreased with the increase of the concentrations of NGF (P < 0.05).</p><p><b>CONCLUSION</b>The NGF might have direct nutritional effects on PC12 cells, and protect them from injury induced by 2, 5 HD. Moreover, it might also have anti-apoptosis effect to some extent.</p>

The Interaction Between Human TRIM5? Chimera and HIV-1gag Protein in Vitro / 中国生物工程杂志

Objective:To express and purify the TRIM5? chimaera[TRIM5? H(R328-332)] protein and to explore the interaction between the TRIM5? H(R328-332)and HIV-1gag. Methods:The plasmid pET28aTRIM5? H(R328-332) was transformed to E.coli BL21 (DE3) strain ,and the expression of TRIM5? H(R328-332) protein was induced by IPTG,purified with Ni2+ chromatography.The expression and purification of TRIM5? H(R328-332) were analyzed by SDS-PAGE and Western blot,and the interaction between TRIM5? H(R328-332) and HIV-1gag was detected by co-immunoprecipitation,His pull-down and ELISA. Results:The recombinant plasmid pET28aTRIM5? H(R328-332) was successfully expressed in E.coli. The results showed that the purified full length TRIM5? H(R328-332) interacted with HIV-1gag protein. Conclusion:The human TRIM5? chimaera was expressed successfully in vitro,and the study demonstrates that the human TRIM5? chimaera interacts with HIV-1 gag in vitro.