The influence of genetic polymorphisms in drug metabolism enzymes and transporters on the pharmacokinetics of different fluvastatin formulations

The purpose of the present study was to investigate the impact of genetic polymorphism on fluvastatin pharmacokinetics.In addition,we compared the fluvastatin pharmacokinetics differences between extended-release(ER)80 mg tablet and immediate-release(IR)40 mg capsule in terms of drug metabolism enzyme and transporter genetic polymorphisms.In this open-label,randomized,two-period,two-treatment,crossover study(n=24),effects of ABCG2,SLCO1B1,ABCB1,CYP2C9 and CYP3A5 polymorphisms on the pharmacokinetics of fluvastatin were analyzed.The administration dosage for IR 40 mg and ER 80 mg were twice and once daily,respectively,for total 7 d.Blood samples for pharmacokinetic evaluation were taken on the 1st and 7th d.The lower exposure following ER was observed.For ER tablets,SLCO1B1 T521C genotype correlated with AUC 0-24 of repeat doses(P=0.010).SLCO1B1 T521C genotype had no statistically significant effect on AUC 0-24 of IR capsule of fluvastatin after single or repeated doses.In vitro study demonstrated that when the concentration of fluvastatin was low(<1μmol/l),the uptake of fluvastatin in the HEK293-OATP1B1 with SLCO1B1521TT(K m=0.18μmol/l)was faster than that with SLCO1B1521CC(K m=0.49μmol/l),On the other hand,when concentration reached to higher level(>1μmol/l),transport velocity of fluvastatin by HEK293-OATP1B1 with SLCO1B1521TT(K m=11.4μmol/l)and with SLCO1B1521TCC(K m=15.1μmol/l)tend to be the same.It suggests that the increased effect of SLCO1B1 T521C genotype on ER formulation of fluvastatin was mainly caused by lower blood concentrations.We recommend that formulation should be incorporated into future pharmacogenomics studies.

基于改进Harris-SIFT算法的立体匹配

本文运用改进的Harris和SIFT算法实现了图像的快速匹配,旨在提高SIFT算法的实时性。该算法首先利用优化的Harris算法提取图像的角点;然后采用SIFT算法对特征点进行单尺度的特征描述,提取出特征点的128维特征描述符;最后,采用特征点特征向量的欧式距离作为两幅图像的中特征点的相似性判定度量,并用RANSAC剔除错误匹配,实现两幅图像特征点的匹配。实验证明,本文算法在保证精度的同时,大大提高了算法的实时性。