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Objective To prepare loratadine nanoparticle suspension and investigate the stability of it. Methods Loratadine nanoparticle suspension was prepared by anti-tumor agent precipitation method,the nanosuspension was characterized by particle size analyzer and transmission electron microscopy, the optimal prescription was screened, and the stability of nanosuspension was investigated by HPLC. Results The optimal prescription stablizer was SDS and organic phase was ethanol. The drug loading radio was 1:2 and the proportion of organic phase to water was 5:10 and the time of high shear was 5 min. Loratadine suspension was pale blue with a uniform emulsion.The nanoparticles were spherical,with an average particle size of 112.8 nm,the PDI of 0.095 and the Zeta potential of -38.6 mV.The suspension had the best physical and chemical stability at room temperature. Conclusion The preparation method of loratadine suspension with good stability is simple, and it’s expected to become the new nano-drug delivery system of loratadine.
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Objective:To explore the effect of P-glycoprotein ( P-gp) activity on its mediated imatinib mesylate accumulation and intracellular drug membrane permeability. Methods: 1199G/wt ABCB1 and 1199A/mut recombinant plasmids were transferred into HEK293 cells, respectively, and the expression levels of mRNA in different cell models were investigated by RT-PCR. Cell Counting Kit-8(CCK-8) assay was used to detect the drug toxicity in different cell models, HPLC was applied to determine the drug concentra-tion in different cell models and evaluate the intracellular accumulation, and transmembrane resistance experiment was employed to de-tect the transmembrane permeability and evaluate the effect of P-gp activity on drug transportation. Results: Cytotoxicity test showed that the drug concentration in the transferred cells was lower than that in the control group, which proved that P-gp had the function of mediating drug out of cells. HPLC and transepithelial electrical resistance experiment showed that compared with the wild type of AB-CB1 (1199G) cells, mutation of ABCB1 1199A cells had stronger effect on P-gp mediated mesylate imatinib accumulation and drug membrane permeability. Conclusion:The experiment manifested that ABCB1 (1199G/A) site mutation can change the coding protein P-gp activity and the polymorphisms will lead to the increase of mesylate imatinib clearance rate and the decrease of effective drug con-centration in target cells. Meanwhile, the clarification of ABCB1 genetic types in clinics can guide the individualized medication of imatinib mesylate.
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Hepatic fibrosis develops as a wound-healing scar in response to acute and chronic liver inflammation and can lead to cirrhosis in patients with chronic hepatitis B and C. The condition arises due to increased synthesis and reduced degradation of extracellular matrix (ECM) and is a common pathological sequela of chronic liver disease. Excessive deposition of ECM in the liver causes liver dysfunction, ascites, and eventually upper gastrointestinal bleeding as well as a series of complications. However, fibrosis can be reversed before developing into cirrhosis and has thus been the subject of extensive researches particularly at the gene level. Currently, therapeutic genes are imported into the damaged liver to delay or prevent the development of liver fibrosis by regulating the expression of exogenous genes. One technique of gene delivery uses ultrasound targeting of microbubbles combined with therapeutic genes where the time and intensity of the ultrasound can control the release process. Ultrasound irradiation of microbubbles in the vicinity of cells changes the permeability of the cell membrane by its cavitation effect and enhances gene transfection. In this paper, recent progress in the field is reviewed with emphasis on the following aspects: the types of ultrasound microbubbles, the construction of an ultrasound-mediated gene delivery system, the mechanism of ultrasound microbubble-mediated gene transfer and the application of ultrasound microbubbles in the treatment of liver fibrosis.
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Objective: To explore the effect of artesunate (Art) on Akt/GSK-3β/β-catenin signal pathway.Methods: Art at different concentrations (0, 12.5, 25, 50 μg·ml-1) was used to treat human hepatic stellate cells (LX-2), and CCK-8 assay was used to detect the cell proliferation to determine the optimal concentration.Art inhibitor (MK-2206) at different concentrations (0~8 μmol·L-1) was given to LX-2 cells, and a Western Blot method was applied to determine the optimal inhibition concentration.Art, MK-2206 and MK-2206+Art were respectively given to LX-2 cells, and a Western Blot method was used to detect the levels of Akt, p-Akt, GSK-3β, p-GSK-3β and β-catenin proteins.Results: CCK-8 assay was used to detect the cell survival rate, and the survival rate was 80% after the 24-hour treatment with 25 μg·ml-1 Art.The results of Western Blot showed that MK-2206 at 6 μmol·L-1 could effectively inhibit the expression of p-Akt.Compared with those of the control group, the levels of Akt, p-Akt, p-GSK-3β and β-catenin protein were significantly different (P＜0.05) in Art (25 μg·ml-1) group, MK-2206 (6 μmol·L-1) group and MK-2206 (6 μmol·L-1) + Art (25 μg·ml-1) group.The expression of GSK-3β and Akt in MK-2206+Art group had no significant difference when compared with that in Art group and MK-2206 group (P＞0.05), while the levels of p-Akt, p-GSK-3β and β-catenin were significantly reduced (P＜0.01).Conclusion: Art exhibits the influence on the relative factors in Wnt/β-catenin signal pathway by Akt/β-catenin, subsequently inhibits the cell proliferation and alleviates the liver fibrosis process.