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Extracellular vesicles (EVs) have recently received much attention about the application of drug carriers due to their desirable properties such as nano-size, biocompatibility, and high stability. Herein, we demonstrate orange-derived extracellular vesicles (OEV) nanodrugs (DN@OEV) by modifying cRGD-targeted doxorubicin (DOX) nanoparticles (DN) onto the surface of OEV, enabling significantly enhancing tumor accumulation and penetration, thereby efficiently inhibiting the growth of ovarian cancer. The obtained DN@OEV enabled to inducement of greater transcytosis capability in ovarian cancer cells, which presented the average above 10-fold transcytosis effect compared with individual DN. It was found that DN@OEV could trigger receptor-mediated endocytosis to promote early endosome/recycling endosomes pathway for exocytosis and simultaneously reduce degradation in the early endosomes-late endosomes-lysosome pathway, thereby inducing the enhanced transcytosis. In particular, the zombie mouse model bearing orthotopic ovarian cancer further validated DN@OEV presented high accumulation and penetration in tumor tissue by the transcytosis process. Our study indicated the strategy in enhancing transcytosis has significant implications for improving the therapeutic efficacy of the drug delivery system.
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In order to successfully develop the effective population pharmacokinetic model to predict the concentration of propofol administrated intravenously, the data including the concentrations across both distribution and elimination phases from five hospitals were analyzed using nonlinear mixed effect model (NONMEM). Three-compartment pharmacokinetic model was applied while the exponential model was used to describe the inter-individual variability and constant coefficient model to the intra-individual variability, accordingly. Covariate effect including the body weight on the parameter CL, V1, Q2, V2, Q3 and V3 were investigated. The performance of final model was assessed by Bootstrapping, goodness-of-fit and visual predictive checking (VPC). The context-sensitive half-times and the infusion rates necessary to maintain the concentration of 1 microg x mL(-1) were simulated to six subpopulations. The results were as follows: the typical value of CL, V1, Q2, V2, Q3 and V3 were 0.965 x (1 + 0.401 x VESS) x (BW/59)(0.578) L x min(-1), 13.4 x (AGE/45)(-0.317) L, 0.659 x (1 + GENDER x 0.385) L x min(-1), 28.8 L, 0.575 x (1 + GENDER x 0.367) x (1 - 0.369 x VESS) L x min(-1) and 196 L respectively. Coefficients of the inter-individual variability of CL, V1, Q2, V2, Q3 and V3 were 29.2%, 46.9%, 35.2%, 40.4%, 67.0% and 49.9% respectively, and the coefficients of residual variability were 24.7%, 16.1% and 22.5%, the final model indicated a positive influence of a body weight on CL, and also that a negative correlation of age with V1. Q2 and Q3 in males were higher than those in females at 38.5% and 36.7%. The CL and Q3 were 40.1% increased and 36.9% decreased in arterial samples compared to those in venous samples. The determination coefficient of observations (DV)-individual predicted value (IPRED) by the final model was 0.91 which could predict the propofol concentration fairly well. The stability and the predictive performance were accepted by Bootstrapping, the goodness-of-fit and VPC. The context-sensitive half-times and infusion rates necessary to maintain the concentration of 1 microg x mL(-1) were different obviously among the 6 sub-populations obviously. The three-compartment model with first-order elimination could describe the pharmacokinetics of propofol fairly well. The involved fixed effects are age, body weight, gender and sampling site. The simulations in 6 subpopulations were available in clinical anesthesia. The propofol anesthesia monitor care could be improved by individualization of pharmacokinetic parameter estimated from the final model.
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Aim To investigate the effects of CYP2C19 polymorphism on the pharmacokinetics and comparative bioavailability of omeprazole in Chinese population.Methods Eighteen healthy male volunteers were selected,of whom 6 were CYP2C19 wild type(w/w),6 were CYP2C19 heterozygous variant(w/m) and the rest were CYP2C19 homozygous variant(m/m).A randomized two-period crossover study was performed.Subjects were assigned to receive test or reference omeprazole as a single oral dose of 40 mg randomly.After a washout period of one week,subjects received the alternative omeprazole formulation.Multiple blood samples of 3 ml were obtained over 12 h after dosing and plasma concentrations of omeprazole were measured by LC/MS method.The modeling of individual pharmacokinetics and the pharmacokinetic parameters of omeprazole were estimated by 3P97.Results The AUC and Cmax of reference omeprazole formulation in w/w,w/m,m/m groups were 1178.44±340.24,2328.10±1011.83,5062.02±1097.29 μg·h·L~(-1) and 602.87±118.25,926.43±134.48,1406.29±233.58 μg·L~(-1),respectively,with significant differences among the three groups(P<0.05).Significant differences were also observed in other pharmacokinetic parameters such as k_e、CL/F、t_(1/2) and Vd/F among the three groups(P<0.05).With regard to test omeprazole formulation,the AUC and C_(max) in w/w,w/m,m/m groups were 1224.82±531.67,2723.34±519.29,5692.49±1575.35 μg·h·L~(-1) and 618.74±231.43,910.67±125.99,1303.31±152.01 μg·L~(-1),respectively,which,as well as k_e,CL/F,t_(1/2) and Vd/F were significant different among the three groups(P<0.05).No significant differences were observed in comparative bioavailability among groups with the values of 94.29%±14.06%,93.08%±11.22%,91.84%±13.03% in w/w,w/m,m/m groups respectively(P>0.05).Conclusions Different CYP2C19 genotypes,leading to functional heterogeneity of CYP2C19,may affect pharmacokinetic profile of omeprazole.Therefore,genotyping CYP2C19 gene before omeprazole therapy will be of great benefit for optimizing individual therapy regimen.There is no significant difference of omeprazole comparative bioavailability with regard to CYP2C19 genetic polymorphism.
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Gene chip is an important biological technology, which is developing quickly recently. In this article, we reviewed the origin, development, basic operation of gene chip. Several kinds of gene chips including tiled array, direct allele specific fluorescence targeting (DAFT) array, labeled auxiliary oligonucleotides array, ligase detection reaction array, and peptide nucleic acid array were introduced as examples for their use in mutation detection. The prospect of the use of gene chip in optimizing drug therapy was also discussed.
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AIM:To study the pharmacokinetics and relative bioavailability of citalopra hydrobromide in human plasma.METHODS:The citalopra hydrobromide concentrations in plasma were determined by HPLC-UV.The column was Lichrospher ODS(5 ?m,250 mm?4.6 mm).The mobile phase was acetonitrile-0.1 mol/L KH2PO4 buffer-triethylamine(35:65:0.3,v/v/v).The flow rate was 1 mL/min.The detection wavelength was 240 nm.The test and reference formulations of citalopra were given to 18 healthy male volunteers.RESULTS:The calibration curve was linear within the range of 2-128 ?g/L,r=0.9992.The minimum detection limit was 1 ?g/L.The recovery was 80%-88%,the RSDs of inter-day and intra-day were not more than 15%.After a single oral dose of 20 mg citalopra hydrobromide was given,the main pharmacokinetic parameters tmax were(4.6?1.0),(4.4?1.4) and(4.0?1.4) h;Cmax were(70?19),(71?17) and(66?21) ?g/L;and t1/2 were(37?9),(37?6) and(36?6) h respectively.CONCLUSION:No significant difference exists among the pharmacokinetic parameters of the three formulations.They are bioequivalent.
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Objectives:To study the pharmacokinetics and relative bioavailability of glipizide in healthy male volunteers. Methods:The glipizide concentrations in plasma were determined by HPLC UV. The column: Lichrospher C18 (5 ?m,150 mm?4.6 mm),the mobile phase: methanl∶0.01 mol/L sodium acetale buffer (pH 4.8) (59 ∶41); the flow rate:1 ml/min, the detection wavelength: 225 nm. The test and reference formulations of glipizide were given to 20 healthy male volunteers. Results: The calibration curve was linear within the range of (25～1 000)?g/L, r =0.999 4. The minimum detection limit was 25 ?g/L. The mean recovery was 89.84%, CV of inter day and intra day were no more than 5%.After a single oral dose of 10 mg glipizide test or reference tablet, the main pharmacokinetic parameters AUC 0-15, AUC 0-∞, T max ,C max and t 1/2 were (3 502.78?635.82) , (3 214.23?590.46)?g/( L?h),(3 868.22?699.93), (3 593.94?638.60)?g/(L?h),(3.85?1.44), (3.76?1.13)h, (550.80?110.19), (531.15?148.42)?g/L,(3.57?1.11)h and (3.80?1.06)h ,respectively. The relative bioavailability F 0-15 ,F 0-∞ were (110.6?19.8)% and (108.8?17.9)%. Conclusions: No significant difference exists among the pharmacokinetic parameters for the experimental tablets and the reference. The two formulations were bioequivalent.
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Objectives: To study the protective effects of Nao Mai Tong(NMT) on middle cerebral artery occlusion(MCAO) induced focal brain ischemia reperfusion injury in rats. Methods: After rats were respectively given NMT 1 g/kg, 3 g/kg, 9 g/kg ig everyday for 1 week, the effects of NMT on the histological changes and behavior disorder caused by focal brain ischemia reperfusion which was made by occlusion of middle cerebral artery were investigated. The gasping time after the cutting of the head in ischemia reperfusion rat was recorded. The contents of ATP and LA were determined by radioimmunoassay. Results: NMT significantly reduced the extent of behavior disorder, descended the rate of cerebral infarction area, and improved histological injury of brain tissues. The grasping time after head cutting was prolonged. It was found that the level of ATP was increased and LA was decreased markedly. Conclusions: NMT shows a significant protective effect on histological, behavior and energy metabolic consequences of MCAO induced focal brain ischemia reperfusion injury.
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NAT2 is an important drug metabolizing enzymes in humans.Polymorphisms in NAT2 gene produce variants at amino acid including seven mutation sites.In vivo NAT2 takes part in 20 kinds of drugs metabolism and activation of carcinogen.Polymorphism of NAT2 has been related to some diseases.This paper reviews the polymorphisms and genotyping about NAT2 and their implications in drug and clinical research.
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Aim To establish a simple reverse dot blot m ethod (RDB) for detecting the genotype of NAT2 in Chinese people. Methods PCR was performed to obtain a biotin labeled DNA fragment. Allele specific oligonucleotide probes were spotted onto a nylon membrane. The DNA fragment hybridized with the membrane under stringent conditions. Finally, a nonradioactive colorimetric reaction was used to detect five mutants of NAT2. NAT2 genotypes of 48 patients with pulmonary tuberculosis were detected with RDB.Results The results obtained from RDB were in consistent with those from allele specific amplification. The NAT2 allele frequencies of *5, *6, *7 were 1.04%, 22.9% and 15.6%, respectively.Homozygous wildtype,heterozygous mutant and homozygous mutant subjects were 33.3%, 54.2% and 12.5%, respectively.Conclusion RDB method was proved to be accurate and convenient, it can be u sed in rational drug therapy.
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Objective:To simulate human N-acetyltransferase 2 protein 3D model by computer technology. Methods: 3D model of human N-acetyltransferase 2 protein was simulated with protein list and computer technology,the physical,chemical,biological characteristics and the functions were analyzed.Results: The possible structure of NAT2 was simulated using ANTHEPORT5.0,a software for determining the sequence of protein,forecasting the pHi and molecular weight of NAT2 were 5.495 and(33 544) respectively.The titration curve and physics-chemistry characteristic curve of NAT2 were also obtained.A Helical Wheel chart was plotted,aiming at the fragment of NAT2 around amino acid 282 nd.Conclusion:The possible structure of NAT2 was simulated using computer,analysis and forecast was also carried out,the method was feasible to genetic analysis of NAT2.
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N-acetyltransferase 2 is an important metabolic enzyme in the human body,participating mainly in the metabolism of medicine containing nitrogen.Presently a lot of researches have been undertaken in the respects like the determination of NAT2 genotype and drug metabolism and so on.In the recent years,more and more attention is paid to the simulation of three-dimension(solid)structure of protein,but the study is just at the outset on three-dimension structure of the NAT2 as well as its structure-function relationship when combined with drug.The research progress of construction of the three-dimension structure of NAT2 is summarized,emphasizing on its methods and tools.
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Objective: To evaluate the anti-hepatitis effect of Yinzhiku Compound and obtain pharmacodynamic evidence for its clinical application.Methods: Using the model of HepG2.2.15 cells,we determined the inhibitory effects of the drug extract with water and that with alcohol on HbsAg and HbeAg from the HepG2.2.15 cells by serum pharmacological methods.Results: The inhibition of the two Abstracts on HbsAg reached the peak on the sixth day and gradually dropped afterwards,but still at a high level on the twelfth day.Their inhibitory effect on HbeAg,too,attained the highest level on the sixth day,but did not fall obviously afterwards and remained high even on the twelfth day.Conclusion: Yinzhiku Compound has a high inhibitory effect on both HbsAg and HbeAg,with no evident difference between the drug extract with water and that with alcohol.
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AIM To develop a sensitive, specific and reliable reversed-phase high performance liquid chromatographic method(RP-HPLC) to determine the total and unbound(free) concentrations in human plasma of amitriptyline and its major metabolite, nortriptyline. METHODS The assay involved a simple extraction procedure. The mobile phase consisted of acetonitrile and distilled water(30∶70, V/V), containing triethylamine(0.5%) and orthophosphoric acid(0.3%), pH 3.1. Separation was achieved on the C18 ODS column and the effluent was measured for UV absorption at 240 nm. RESULTS The calibration curves were linear in the range of 4～400 μg*L-1 for total concentration, and in the range of 4～64 μg*L-1 for free concentration for both amitriptyline and nortriptyline. The lowest limits of detection were 4 μg*L-1 for both compounds. The absolute recovery rates were 102.0%±3.77% for amitriptyline and 99.3%±7.13% for nortriptyline. The precision values(RSD) of intra-day and inter-day for both amitriptyline and for nortriptyline were determined to be <5%, and <8%, respectively. The method was applied to determine the total and free concentrations in plasma of the healthy volunteers after a single oral dose of 50 mg amitriptyline. CONCLUSION The assay was simple, repid, highly selective and sensitive. It is suitable for the routine analysis of total and free drug concentrations in plasma using readily available instruments with lower cost.
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AIM: To study the pharmacokinetics and rela ti ve bioavailability of naftopidil in healthy male volunteers. METHODS: The naftopidil concentrations in plasma were determined by HPLC. The test and reference formulations of naftopidil were given to 18 healthy male volunteer s. The calibration curve was linear within the range of 1.6 - 400 ?g?L -1 , r=1. The minimum detection limit was 1 ?g?L -1 . The mean recovery rate was 85.2 %- 89.9 %, RSDs of inter-day and i ntra-day were no more than 8.0 %. RESULTS: After a single o ral dose of 50 mg naftopidil test capsules or reference tablets, the main pharma cokinetic parameters AUC 0-24 : 295.6 ? 90.9 and 291.6 ? 89.3 ?g?L -1 ?h -1 ; AUC 0-∞ : 320.0 ? 97.2 and 318.0 ? 98.3 ?g?L -1 ?h -1 ; T max : 0.6 ? 0.2 and 0 .6 ? 0.2 h ; C max : 129.1 ? 60.7 and 138.3 ? 72.5 ?g? L -1 ; T 1/2 : 5.9 ? 1.7 and 6.4 ? 2.1 h , respectively. The relative bioavailability F 0-24 ,F 0-∞ were 101.9 ? 12.9 % and 101.2 ? 12.3 %, respectively. CONCLUSION: No signifi cant difference exists among the pharmacokinetic parameters for the test capsule s and the reference tablets of naftopidil. The two formulations were bioequivale nt.
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Genetic polymorphisms in drug-metabolizing enzymes,transporters,receptors,and other drug targets have been linked to interindividual differences in the efficacy and toxicity of many medications.Pharmacogenomics is to study of how genes affect the individual response to drugs.There are some evidences that in the future the use of pharmacogenomics could help to enhance the effects of drugs and reduce the adverse drug reactions(ADRs),as it aims to predict which patients are likely to respond to a particular drug and which patients are likely to have significant ADRs.Pharmacogenomics studies are rapidly elucidating the inherited nature of these differences in drug disposition and effects,thereby providing a strong scientific basis for optimizing drug therapy on the basis of each patient's genetic constitution.In this article some examples of genetic polymorphisms which affecting drug pharmacokinetics(in protein binding of drugs in plasma)and pharmacodynamics(correlated with antihypertensive drugs)are briefly illustrated.
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AIM To develop a sensitive, specific and reliable reversed phase high performance liquid chromatographic method(RP\|HPLC) to determine the total and unbound(free) concentrations in human plasma of amitriptyline and its major metabolite, nortriptyline. METHODS\ The assay involved a simple extraction procedure. The mobile phase consisted of acetonitrile and distilled water(30∶70, V/V ), containing triethylamine(0 5%) and orthophosphoric acid(0 3%), pH 3 1. Separation was achieved on the C18 ODS column and the effluent was measured for UV absorption at 240 nm. RESULTS The calibration curves were linear in the range of 4～400 ?g?L -1 for total concentration, and in the range of 4～64 ?g?L -1 for free concentration for both amitriptyline and nortriptyline. The lowest limits of detection were 4 ?g?L -1 for both compounds. The absolute recovery rates were 102 0%?3 77% for amitriptyline and 99 3%?7 13% for nortriptyline. The precision values(RSD) of intra day and inter day for both amitriptyline and for nortriptyline were determined to be