共查询到10条相似文献,搜索用时 78 毫秒
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??OBJECTIVE To establish a measuring method for microdialysis probe recovery of ginsenoside Rg1 and investigate the effects of flow rate, concentration and using times of probe on the recovery in vivo and in vitro. METHODS Dialysis method and retrodialysis method were used for the study. The concentration of ginsenoside Rg1 in brain and blood dialysate was determined by LC-MS/MS and the probe recovery was calculated. RESULTS The recoveries of brain and blood microdialysis probes showed good stability within 10 h, with average values of 17.0% and 34.4% respectively for ginsenoside Rg1 at 1.5 ??L??min-1. Concentrations (50,200,500,1 000 ng??mL-1) had no obvious effect on recovery. At the same concentration, the recovery of brain and blood probes for ginsenoside Rg1 decreased with the increase of flow rate (0.5, 1.0, 1.5, 2.0, 3.0 ??L??min-1) in vitro and in vivo. The dialysis recoveries of brain and blood probes in vitro were (40.6??4.3)%, (23.5??2.3)%, (17.7??0.8)%, (12.2??1.1)%, (8.8??0.6)% and (70.6??3.6)%, (46.0??2.1)%, (32.9??1.6)%, (25.6??0.7)%, (18.2??1.3)%, respectively. The recoveries of dialysis and retrodialysis in vitro were approximately equal, and the recovery detected by retrodialysis in vivo was similar with the in vitro results. Probe used for no more than 3 times still kept high transmittance by flushing with 2% heparin sodium and ultrapure water successively. CONCLUSION Retrodialysis method can be used to study brain and blood probe recovery in vivo, and microdialysis can be used for simutaneous pharmacokinetic studies of ginsenoside Rg1 in intercelluar fluid and blood. 相似文献
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??OBJECTIVE To determine the recovery rates of blood and brain microdialysis probes of acetylglutamine(NAG) and its decomposition products glutamic acid (Glu) and ??-aminobutyric acid (GABA) in vitro, and lay the foundation for the pharmacokinetic study of NAG in blood and brain.METHODS The concentrations of NAG, Glu and GABA in blood and brain microdialysates were determined by LC-MS/MS and the probe recoveries were calculated. The in vitro recoveries of NAG, Glu and GABA were studied using positive dialysis and retrodialysis methods at different flow rates and concentrations.RESULTS The in vitro recoveries of blood and brain probes of NAG, Glu and GABA were inversely proportional to the perfusate flow rates while independent of drug concentrations. The recovery rates obtained by positive dialysis and retrodialysis methods in vitro were approximately equal under the same condition, and were stable for at least 6 h.CONCLUSION Retrodialysis method can be used to study the probe recovery of NAG, and microdialysis can be used for blood and brain pharmacokinetic study of NAG. 相似文献
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??OBJECTIVE To investigage the effects of celastrol-triggered HeLa cells autophagy and the molecular mechanisms in vitro and in vivo. METHODS The antiproliferative effect of celastrol was detected using MTT assay. Apoptotic rate and cell cycle were evaluated using flow cytometric analysis. Autophagy was detected using fluorescence microscope. Protein expression was evaluated using Western blotting. Tumor growth was evaluated by subcutaneous xenograft model in vivo. RESULTS Celastrol inhibited HeLa cells proliferation and induced HeLa cells autophagy and cell cycle arrest at G0/G1 phase, but not induced HeLa cell apoptosis in vitro. The protein expression of Beclin 1 was up-regulated and the conversion from LC3 ?? to LC3 ?? was increase in HeLa cells in vitro after treatment with celastrol. Moreover, celastrol promoted the protein expression of PTEN??p-ERK1/2??p-MEK1/2 and inhibited the phosphorylated of Akt, p70S6K and mTOR in HeLa cells. After pretreatment with 3-methyladenine (5 mmol??L-1), the antiproliferative and induced-autophagy effects of celastrol were reversed. Furthermore, celastrol inhibited tumor growth and the protein expression of p-Akt and p-mTOR, but up-regulated the protein expression of LC3 ?? and Beclin 1 in vivo. CONCLUSION Antitumor effect of celastrol dependent on cells autophagy in HeLa cells via inhibition of Akt/mTOR signaling pathway in vitro and in vivo. 相似文献
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??OBJECTIVE To prepare the tulobuterol crystal reservoir patch, and to evaluate morphology, stability and crystallization factors of the crystal in the patch, adhesive force, dissolution, transdermal properties in vitro and the pharmacokinetics in rabbits. METHODS The transdermal patch was prepared on the basis of drug recrystallization and characterized by morphology, stability and crystallization factors using microscope and adhesive force using initial adhesion tester, adhesion tester and peel tester. The dissolution and transdermal properties were evaluated by using the dissolution tester and transdermal tester. In addition, pharmacokinetics was studied using New Zealand rabbits as experimental animals. RESULTS The drug crystals were evenly distributed in the form of filaments, which had average width of (4.4??1.8)??m and kept stable at 2-40 ??. The crystallization in patches is affected by tulobuterol supersaturation and temperature. The adhesive force of patch was suitable and its dissolution matched standard which can be fitted by the Higuchi equation. In the diffusion cell in vitro, the drug penetrated through the skin in a Zero-order kinetic equation, and the cumulative penetration percentage and skin retention concentration were 92.04% and 10.36 ??g??cm-2 with in 24 h. The pharmaceutic parameters showed that the tulobuterol blood concentration can be maintained within 24 h, whose tmax and ??max were (6.67??3.06)h and (3.08??1.32) ng??mL-1, respectively. CONCLUSION The tulobuterol crystal reservoir patch can be established by control of recrystallization conditions. The patch has good adhesive properties and sustained release characteristics in vitro and in vivo, which has the practical significance for further study. 相似文献
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??OBJECTIVE To evaluate the anti-hepatitis B virus (HBV) activity of herpetrione nanosuspension (PEDX-NS) both in vitro and in vivo. METHODS HepG2 2.2.15 cells and duck hepatitis B virus (DHBV) infected ducks as in vitro and in vivo models were used to compare the anti-HBV activity of PEDX-NS and PEDX coarse suspension (PEDX-CS). RESULTS In the HepG2 2.2.15 cell, PEDX-NS effectively suppressed the secretion of the HBV antigens (HBsAg and HBeAg) in a dose-dependent manner with significant difference from PEDX-CS (P<0.05 or P<0.01). In the in vivo evaluation, PEDX-NS with high dose (100 mg??kg-1) and middle dose (60 mg??kg-1) significantly reduced the serum HBV DNA level (P<0.05 or P<0.01) and the effect was better than that of PEDX-CS (P<0.05 or P<0.01). CONCLUSION The result revealed that PEDX-NS exhibits anti-HBV activity both in vitro and in vivo and its effect was superior to that of PEDX-CS. The mechanism is probably that the small particle size of PEDX-NS provides a large specific surface area that resulted in better absorption in vivo, thus enhancing its anti-HBV activity.
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??OBJECTIVE To prepare ion-sensitive ophthalmic in situ gel containing bendazac lysine (BDZL-ISG) and preliminarily study its rheological behavior, in vitro drug release, corneal permeation, and pharmacokinetics in rabbit aqueous humor. METHODS Single factor investigation was carried out to optimize the formulation, taking viscosity and gelling capacity as evaluation indices. Using aqueous solution or eye drops as control, the in vitro release of the formulation was evaluated by dialysis membrane method. Then, the corneal permeation experiment of the optimum formulation was carried out with Franz diffusion cell. The pharmacokinetics of BDZL-ISG in rabbit aqueous humor was preliminarily studied by microdialysis. RESULTS Compared with the control group, the optimum formulation had shear thinning behavior and significant sustained release effect. There was no significant difference in the corneal permeation between the two groups. The RESULTS of pharmacokinetic study showed that ??max (13.25 ??g??L-1) and AUC0-t of BZDL-ISG were 2.38 and 2.2 times higher than those of BDZL eye drops respectively, which suggested that the ocular bioavailability of BDZL was greatly enhanced by the optimum in situ gel formulation. CONCLUSION With significant sustained release effect, the ion-sensitive ophthalmic in situ gel will become a promising alterative formulation for bendazac lysine for treatment of cataracts. 相似文献
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目的 通过比较国产非那雄胺片与原研制剂的体外溶出行为,评价仿制药与参比制剂的质量一致性,利用计算机模拟技术分析体内外相关性。方法 参照《中国药典》2015年版方法(2020年版《中国药典》该项目没有变化),分别考察国产制剂与原研制剂在4种不同溶出介质(pH 1.2盐酸溶液、pH 4.5醋酸盐溶液、pH 6.8磷酸盐溶液、水)中的体外溶出行为。同时借助GastroPlusTM软件结合体外溶出试验结果,建立非那雄胺片体内外相关性模型。结果 在选定条件下,国内15家制药公司中有3家公司产品在4种溶出介质中的溶出曲线均与原研制剂相似。软件分析结果提示,体外溶出曲线与软件模拟的体内行为不相似。结论 大部分非那雄胺片仿制制剂在体外的溶出曲线与原研制剂存在一定的差异,国产非那雄胺片工艺水平及处方有待提高,反映体内释放行为的生物体相关溶出条件有待进一步研究。 相似文献
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??OBJECTIVE To improve the dissolution rate of fenofibrate (FNB) by using starch source mesoporous carbon (SMC) as a carrier and achieve controlled release of the drug by utilizing double-layer osmotic pump technology to improve the oral bioavailability. METHODS FNB was loaded into the mesoporous of NMS by adsorption method to prepare the drug loading system (FNB-SMC). Differential scanning calorimetry (DSC) and powder X-ray diffraction (PXDR) were used to characterize the present state of the drug before and after being loaded. The dissolution rate of FNB-SMC was investigated by in vitro dissolution test, and the formulation of the double-layer osmotic pump tablets of FNB-SMC was optimized. The oral bioavailability of the self-made tablet was investigated by in vivo experiment in rabbits. RESULTS FNB existed in the mesoporous of SMC in an amorphous state. The in vitro dissolution test showed that NMS could significantly increase the dissolution rate of FNB, and the double-layer osmotic pump technology could achieve Zero-order release of the drug. The in vivo experiments showed that the oral bioavailability of the self-made tablets was significantly improved. CONCLUSION The combination of starch source mesoporous carbon carrier and double-layer osmotic pump technology prevente the burst effect and significantly improve the oral absorption of FNB. 相似文献