1.Formulation Optimization of Budesonide Sustained-release Tablet by Central Composite Design-response Surface Method
Yuanzhi REN ; Tao ZHANG ; Hua HUANG ; Xiujie LIU ; Jingsong ZHOU
China Pharmacy 2017;28(10):1395-1398
OBJECTIVE:To optimize the formulation of Budesonide sustained-release tablet. METHODS:Using the cumula-tive releases in 2,4,8 h as investigation indexes,central composite design-response surface method was used to optimize the amount of hydroxypropylcellulose L(HPC-L),amount of soybean phosphatides,and filler(fixed total 200 mg)lactose- micro-crystalline cellulose mass ratio in the formulation of Budesonide sustained-release tablet,and the verification test was conducted. The release behaviors of prepared sustained-release tablet and original preparation in pH 7.2,7.0,6.8 phosphate buffer were com-pared. RESULTS:The optimal formulation was as follow as budesonide of 9 mg,HPC-L of 46.49 mg,soybean phosphatides of 9.23 mg,filler lactose-microcrystalline cellulose mass ratio of 1:2.9;the cumulative releases in 2,4,8 h were 21.9%,50.1%, 99.5%,the relative errors with predicted values (22.0%,50.0%,98.5%) were 0.45%,0.20%,1.02%(n=3),respectively. Compared with cumulative release of original preparation,the f2 was higher than 50. CONCLUSIONS:Budesonide sustained-re-lease tablet is successfully prepared,which shows similar release behavior to original preparations.
2.Clinical application of three-dimensional reconstruction of ilium bone flap
Jianwei LI ; Yong LIU ; Yijun REN ; Lei LEI ; Kuanhai WEI ; Yuanzhi ZHANG ; Guoxian PEI
Chinese Journal of Orthopaedic Trauma 2009;11(4):338-341
Objective To discuss an initial clinical application of three-dimensional reconstruction of ilium bone flap. Methods From December 2006 to June 2008, bone defects of 6 patients with frac-tures of femoral shaft and tibia were repaired using vascularized iliac bone flap. After injection of contrast a-gent, CT scan was performed. Amira 4.0 Software was applied to reconstruct personalized three-dimensional structures of the iliac bone flap. The points, lines, and surfaces were marked in the personalized three-dimensional images reconstructed to provide guidance for the actual surgery. Results The person-alized three-dimensional reconstruction of iliac bone flap for the 6 individual patients were successfully used in the actual surgery. The three-dimensional structures of blood vessels, bone and adjacent relationship which had been clearly shown in the reconstructed flaps were confirmed by the actual surgical findings. All the 6 lilac bone flaps survived uneventfully. Conclusion The preoperative three-dimensional reconstruction of lilac bone flap by CT scan, angiography and digital technology can provide a useful aid for actual surgical design and harvest of the flap, minimizing intraoperative injury to blood vessels and enhancing flap survival.
3.Hyperuricemia accompanied with changes in the retinal microcirculation in a Chinese high-risk population for diabetes.
YuanZhi YUAN ; M Kamran IKRAM ; SunFang JIANG ; HuanDong LIN ; LiMin REN ; HongMei YAN ; JianHua SHENG ; XuSheng CHEN ; Xin GAO
Biomedical and Environmental Sciences 2011;24(2):146-154
OBJECTIVETo investigate the association of retinal vascular calibers with hyperuricemia in a middle-aged and elderly population.
METHODSA cross-sectional design was applied in this study and 869 participants aged =40 years from a high-risk group for diabetes were recruited. All participants received the anthropometrical measurements and laboratory tests. Retinal arteriolar and venular caliber of the participants were measured with a semi-automated system. Hyperuricemia was defined as a serum uric acid level >420 μmol/L in men and >360 μmol/L in women. Linear regression models were used to assess the association of hyperuricemia with retinal vascular calibers. These models were additionally adjusted for age, central obesity, hypertension, dyslipidemia, weekly activity, smoking status, and education.
RESULTSAmong the 869 participants, 133 (15.3%) suffered from hyperuricemia. The crude mean serum uric acid level was 312.3 μmol/L (Standard Deviation 79.5); mean concentration was 355.0 μmol/L (SD 75.5) in male participants, and 288.0 μmol/L (SD 71.1) in female participants (age-adjusted difference 58.1 μmol/L, 95% Confidence Internal 48.5, 67.6). After adjusting for additional covariates, male participants with hyperuricemia had 3.77 μm (95% CI -0.46, 8.00) smaller arteriolar caliber and 6.20 μm (95% CI 0.36, 12.04) larger venule than those without hyperuricemia; the corresponding numbers among female participants were 1.57 μm (95% CI -1.07, 4.21) for retinal arteriolar caliber and 2.28 μm (95% CI -1.72, 6.27) for retinal venular caliber.
CONCLUSIONHyperuricemia was associated with smaller retinal arteriolar caliber and larger venular caliber mainly in male participants in this study.
Adult ; Aged ; China ; epidemiology ; Diabetes Mellitus ; epidemiology ; Female ; Humans ; Hyperuricemia ; complications ; Male ; Middle Aged ; Retinal Vessels ; pathology ; Risk Factors ; Sex Characteristics
4.Determination of a visco-hyperelastic material law based on dynamic tension test data.
Lihai REN ; Chengyue JIANG ; Yong CHEN ; Yuanzhi HU
Journal of Biomedical Engineering 2018;35(5):767-773
The objective of this study was to determine the visco-hyperelastic constitutive law of brain tissue under dynamic impacts. A method combined by finite element simulations and optimization algorithm was employed for the determination of material variables. Firstly, finite element simulations of brain tissue dynamic uniaxial tension, with a maximum stretch rate of 1.3 and strain rates of 30 s and 90 s , were developed referring to experimental data. Then, fitting errors between the engineering stress-strain curves predicted by simulations and experimental average curves were assigned as objective functions, and the multi-objective genetic algorithm was employed for the optimation solution. The results demonstrate that the brain tissue finite element models assigned with the novel obtained visco-hyperelastic material law could predict the brain tissue's dynamic mechanical characteristic well at different loading rates. Meanwhile, the novel material law could also be applied in the human head finite element models for the improvement of the biofidelity under dynamic impact loadings.