scholarly journals Comparative Pharmacokinetics and Bioavailability of Three Ephedrines in Rat after Oral Administration of Unprocessed and Honey-Fried Ephedra Extract by Response Surface Experimental Design

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Yezhe Cheng ◽  
Yu Zhang ◽  
Hang Xing ◽  
Kun Qian ◽  
Longshan Zhao ◽  
...  
Keyword(s):  
Oral Administration ◽  
Response Surface ◽  
Critical Role ◽  
Precipitation Method ◽  
Surface Method ◽  
Pharmacokinetics Study ◽  
Pharmacokinetic Properties ◽  
The Mean ◽  
Acetate Aqueous Solution ◽  
Lower Limits

Ephedra have been used as a common traditional Chinese medicine for thousands of years. However, the perspiration effect of the unprocessed ephedra was too strong. Clinical trials have shown that processing methods play a critical role in moderating the perspiration property of ephedra according to the needs. A LC-MS/MS method was developed and validated to compare the pharmacokinetic properties of the three ephedrines after oral administration of unprocessed and honey-fried ephedra extract. The contents of honey, frying temperature, and frying time were set at 20%, 116°C, and 7 min by the Box-Behnken response surface method, respectively. In the pharmacokinetics study, the biosamples were pretreated and extracted by protein precipitation method with acetonitrile and separated on an Agilent TC-C18column (250 mm × 4.6 mm, 5 μm) using a mobile phase consisting of 0.1% formic acid methanol and 5 mM ammonium acetate aqueous solution (5 : 95, v/v). All calibration curves were linear (r>0.9932) with lower limits of quantitation (LLOQs) < 12 ng/mL. The mean recoveries of the three analytes were higher than 75%. The pharmacokinetics study indicated that the reduced absorption of ephedrine hydrochloride (EH) and pseudoephedrine hydrochloride (PEH) in honey-fried ephedra group might be the main reason for the moderation of the diaphoretic property.

scholarly journals Simultaneous Determination and Pharmacokinetic Study of Quercetin, Luteolin, and Apigenin in Rat Plasma after Oral Administration of Matricaria chamomilla L. Extract by HPLC-UV

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Xiaoxv Dong ◽  
Wei Lan ◽  
Xingbin Yin ◽  
Chunjing Yang ◽  
Wenping Wang ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Oral Administration ◽  
Simultaneous Determination ◽  
Rat Plasma ◽  
Maximum Plasma Concentration ◽  
Maximum Plasma ◽  
Matricaria Chamomilla ◽  
The Mean ◽  
Lower Limits

A simple and sensitive HPLC-UV method has been developed for the simultaneous determination of quercetin, luteolin, and apigenin in rat plasma after oral administration of Matricaria chamomilla L. extract. The flow rate was set at 1.0 ml/min and the detection wavelength was kept at 350 nm. The calibration curves were linear in the range of 0.11–11.36 μg/ml for quercetin, 0.11–11.20 μg/ml for luteolin, and 0.11–10.60 μg/ml for apigenin, respectively. The intraday and interday precisions (RSD) were less than 8.32 and 8.81%, respectively. The lower limits of quantification (LLOQ) of the three compounds were 0.11 μg/ml. The mean recoveries for quercetin, luteolin, and apigenin were 99.11, 95.62, and 95.21%, respectively. Stability studies demonstrated that the three compounds were stable in the preparation and analytical process. The maximum plasma concentration (Cmax) was 0.29 ± 0.06, 3.04 ± 0.60, and 0.42 ± 0.10 μg/ml, respectively. The time to reach the maximum plasma concentration (Tmax) was 0.79 ± 0.25, 0.42 ± 0.09, and 0.51 ± 0.13 h, respectively. The validated method was successfully applied to investigate the pharmacokinetics study of quercetin, luteolin, and apigenin in rat plasma after oral administration of M. chamomilla extract.

An Efficient Method for Structural Reliability Analysis

2012 ◽  
Vol 204-208 ◽  
pp. 3044-3047
Author(s):  
Liu Ying
Keyword(s):  
Reliability Analysis ◽  
Response Surface ◽  
Response Surface Method ◽  
Structural Reliability ◽  
Analysis Method ◽  
Stochastic Response ◽  
Stochastic Response Surface Method ◽  
Surface Method ◽  
Comparative Accuracy ◽  
The Mean

An efficient reliability analysis method has been proposed in the paper, which based on stochastic response surface method. The key advantage of the stochastic response surface method is that the collocation points are selected for minimizing the mean square error, and from high probability regions, thus leading to fewer function evaluations for high accuracy. Compared with Monte Carlo method, the proposed technique can be more efficiency while achieve comparative accuracy.

A Proposal of PSO with Presumption Function of the Solution Landscape by Response Surface Method

2014 ◽  
Vol 134 (9) ◽  
pp. 1293-1298
Author(s):  
Toshiya Kaihara ◽  
Nobutada Fuji ◽  
Tomomi Nonaka ◽  
Yuma Tomoi
Keyword(s):  
Response Surface ◽  
Response Surface Method ◽  
Surface Method

Development and validation of a LC-MS/MS method for quantification of mobocertinib (TAK-788) in plasma and its application to pharmacokinetic study in rats

2020 ◽  
Vol 23 ◽  
Author(s):  
Bo Li ◽  
Jin Wang ◽  
Xinyao Dou ◽  
Xinjie Zhang ◽  
Xianbei Xue ◽  
...  
Keyword(s):  
Oral Administration ◽  
Pharmacokinetic Study ◽  
High Performance ◽  
Kinase Inhibitor ◽  
Internal Standard ◽  
Selected Reaction Monitoring ◽  
Precipitation Method ◽  
Plasma Samples ◽  
Bioanalytical Method Validation ◽  
Extraction Recovery

Aim and Objective:: An analytical method for the determination of mobocertinib, an investigational tyrosine kinase inhibitor, was developed and optimized by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) in rat plasma. Materials and Methods:: Plasma samples were pretreated by the protein precipitation method with a methanol solution of osimertinib as the internal standard (IS). Chromatographic separation was performed using an Inertsil ODS-3 column (50 mm × 4.6 mm, I.D. 5 μm) column with the temperature maintained at 40 °C. The mobile phase consisted of water (containing 0.1% formic acid) and methanol in a gradient mode at a flow rate of 0.5 mL/min. Mass spectrometric detection was carried out in the selected reaction monitoring (SRM) mode with positive electrospray ionization, and the mass transitions of mobocertinib and osimertinib were m/z 587.01 → 71.88 and m/z 499.80 → 71.94, respectively. The method was validated in terms of selectivity, linearity, accuracy and precision, extraction recovery and matrix effect, stability and carryover as per the guidelines for bioanalytical method validation (FDA, 2018). The method was applied to the pharmacokinetic study of mobocertinib in rats by oral gavage at the doses of 2, 6, and 18 mg/kg. A total of 216 plasma samples from 18 rats were analyzed. Results:: It showed good linearity over the range of 1-1000 ng/mL (R2 = 0.9957). The intra-batch accuracy was within 94.65-102.59% and the precision was within 5.49-10.46%. The inter-batch accuracy was within 97.08-102.25% with a precision of 7.54-10.13%. The extraction recovery and matrix factor were acceptable for the bioanalysis of mobocertinib. Additionally, mobocertinib was found to be stable under the detected conditions. Mobocertinib showed linear pharmacokinetic characteristics following oral administration to rats at 2.0-18.0 mg/kg. Conclusion:: The developed and validated method was successfully employed in the pharmacokinetic study in rats following oral administration of mobocertinib at the doses of 2, 6, and 18 mg/kg.

Application of an LC-MS/MS Method to a Urinary Excretion Study of Triflusal and its Main Metabolite 2-hydroxy-4-trifluoromethyl Benzoic Acid in Human Urine

2020 ◽  
Vol 16 (3) ◽  
pp. 328-334
Author(s):  
Jie Ge ◽  
Jin-Wen Wang ◽  
Qi-Yan Guo ◽  
Ai-Dong Wen
Keyword(s):  
Benzoic Acid ◽  
Urinary Excretion ◽  
Human Urine ◽  
Multiple Reaction Monitoring ◽  
Main Metabolite ◽  
Linear Relationships ◽  
Pharmacokinetic Properties ◽  
Liquid Chromatography Tandem Mass ◽  
Excretion Study ◽  
Acetate Aqueous Solution

Objective: A validated liquid chromatography-tandem mass spectrometry method (LCMS/ MS) was established to simultaneously determine the concentration of triflusal and its main metabolite 2-hydroxy-4-trifluoromethyl benzoic acid(HTB) in human urine. Methods: The separation was performed on a Dikma C18 column using isocratic elution with acetonitrile-4 mmol/L ammonium acetate aqueous solution containing 0.3 % formic acid water (78: 28, V/V). The method involved extraction with methanol using protein precipitation. The precursor-toproduct ion transitions with multiple reaction monitoring was m/z 247.1→161.1, 204.8→106.7and 136.9→93.0 for triflusal, HTB and salicylic acid(IS), respectively. The method showed good linear relationships over the ranges of 0.08 to 48 μg/mL and0.5 to 50 μg/mL. Results: It was the first time that a urinary excretion study of triflusal capsule as oral. The cumulative urinary recovery showed 8.5% and 2.7% for triflusal and HTB, respectively. Conclusion: This method was successfully used for evaluating the pharmacokinetic properties of triflusal and HTB in urine in Chinese healthy subjects.

scholarly journals Creep-Based Reliability Evaluation of Turbine Blade-Tip Clearance with Novel Neural Network Regression

Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3552 ◽  
Author(s):  
Chun-Yi Zhang ◽  
Jing-Shan Wei ◽  
Ze Wang ◽  
Zhe-Shan Yuan ◽  
Cheng-Wei Fei ◽  
...  
Keyword(s):  
Neural Network ◽  
High Pressure ◽  
Reliability Analysis ◽  
Response Surface ◽  
Response Surface Method ◽  
Tip Clearance ◽  
Strong Nonlinearity ◽  
Surface Method ◽  
Blade Tip ◽  
Blade Tip Clearance

To reveal the effect of high-temperature creep on the blade-tip radial running clearance of aeroengine high-pressure turbines, a distributed collaborative generalized regression extremum neural network is proposed by absorbing the heuristic thoughts of distributed collaborative response surface method and the generalized extremum neural network, in order to improve the reliability analysis of blade-tip clearance with creep behavior in terms of modeling precision and simulation efficiency. In this method, the generalized extremum neural network was used to handle the transients by simplifying the response process as one extremum and to address the strong nonlinearity by means of its nonlinear mapping ability. The distributed collaborative response surface method was applied to handle multi-object multi-discipline analysis, by decomposing one “big” model with hyperparameters and high nonlinearity into a series of “small” sub-models with few parameters and low nonlinearity. Based on the developed method, the blade-tip clearance reliability analysis of an aeroengine high-pressure turbine was performed subject to the creep behaviors of structural materials, by considering the randomness of influencing parameters such as gas temperature, rotational speed, material parameters, convective heat transfer coefficient, and so forth. It was found that the reliability degree of the clearance is 0.9909 when the allowable value is 2.2 mm, and the creep deformation of the clearance presents a normal distribution with a mean of 1.9829 mm and a standard deviation of 0.07539 mm. Based on a comparison of the methods, it is demonstrated that the proposed method requires a computing time of 1.201 s and has a computational accuracy of 99.929% over 104 simulations, which are improvements of 70.5% and 1.23%, respectively, relative to the distributed collaborative response surface method. Meanwhile, the high efficiency and high precision of the presented approach become more obvious with the increasing simulations. The efforts of this study provide a promising approach to improve the dynamic reliability analysis of complex structures.

Sign in / Sign up

Export Citation Format

Share Document