1.Gene Polymorphism to the Effects of Low Level Aromatic Solvents Exposure on Spontaneous Abortion
Tongshan LIU ; Dafang CHEN ; Ping YANG
Journal of Environment and Health 1992;0(02):-
Objective To investigate the association between genetic polymorphisms of cytochrome P450 MSP1 gene and the glutathione s-transferase GSTM1 gene in female workers exposed to aromatic solvents and spontaneous abortion. Methods A retrospective epidemiological investigation was carried out among 276 female workers including 58 female workers with history of spontaneous abortion and 218 female workers without spontaneous abortion selected in Yanshan of Beijing by the trained investigators using the unified questionnaire. Results The spontaneous abortion of female workers was significantly associated with GSTM1 (absent) (OR=2.07, 95% CI: 1.15-3.71), but not MSP1 (present) and exposure to aromatic solvent. After adust-ment for major confounders including education, age, shift work, body mass index, passive smoking and occupational stress, the multiple logistic regression analysis showed that GSTM1 gene (absent) significantly increased the risk of spontaneous abortion of female workers (OR=2.15, 95% CI: 1.17-3.98). Before and after adjustment for major confounders including education, age, shift work, body mass index, passive smoking and occupational stess, the multiple regression analysis showed that GSTM1 (absent) combined with MSP1 (heterozygous variant type / homozygous variant type) significantly increased the risk of spontaneous abortion (OR=2.98, 95% CI:l. 17-7.59), using the group with GSTM1 (present) and MSP1 (homozygous wild type) as reference group. Conclusion Our data suggested a genetic influence on spontaneous abortion in this population, GSTM1 (absent) was significantly associaled with spontaneous abortion, also provide evidence of additional joint action of gene MSP1 (heterozygous variant type and homozygous variant type) and GSTM1 (absent) to spontaneous abortion.
2.Efficacy of CSII for diabetes with cholecystitis during peri-operation period
Yan ZHOU ; Dafang WU ; Yu CHEN
Chinese Journal of Diabetes 1994;0(01):-
During the period of peri-operation on gallbladder,T2MD patients with calculous cholecystitis were randomly divided into groups of continuous subcutaneous insulin infusion(CSII,n=32),multiple subcutaneous insulin injection(MSII,n=48) and OHA(n=64).It is found that CSII has better glucose control than MSII and OHA.
3.Metabolites of injected chlorogenic acid in rats.
Cen XIE ; Dafang ZHONG ; Xiaoyan CHEN
Acta Pharmaceutica Sinica 2011;46(1):88-95
Chlorogenic acid (5-CQA) is one of the major components in some Chinese herbal injections. However, the metabolism of 5-CQA in rats after intravenous injection has not been determined. An ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) method was applied to identify the metabolites in bile, urine, feces and plasma after a single intravenous administration of 10 mg x kg(-1) 5-CQA to rats. Using MSE and mass defect filter techniques, a total of 35 metabolites were detected in bile, urine, feces and plasma. The predominant metabolites in bile were glutathione conjugates of O-methyl-5-CQA, accounting for approximately 80% of the metabolites excreted in bile. The major components in urine were parent drug, O-methyl-5-CQA, hydrolyzed metabolites and glucuronide conjugates. The major components in feces were O-methyl-5-CQA and its cysteine conjugates. The major component in plasma was the parent drug. The urinary and fecal excretion pathways were equally important to 5-CQA in rats. These results demonstrate that 5-CQA undergoes extensively metabolism in rats and are highly reactive to nucleophiles such as GSH. This finding indicates that attention should be paid on the injections containing 5-CQA, which may covalently bind to proteins, leading to allergenic drug reactions.
4.The enantioselective pharmacokinetic study of desvenlafaxine sustained release tablet in Chinese healthy male volunteers after oral administration.
Yinxia CHEN ; Jiangbo DU ; Yifan ZHANG ; Xiaoyan CHEN ; Dafang ZHONG
Acta Pharmaceutica Sinica 2015;50(4):486-91
A chiral LC-MS/MS method for the simultaneous analysis of desvenlafaxine (DVS) enantiomers in human plasma was developed and applied to a pharmacokinetic study on 12 Chinese healthy volunteers. d6-Desvenlafaxine was used as internal standard (IS). Chromatographic separation was performed on the Astec Chirobiotic V chiral column (150 mm x 4.6 mm, 5 μm). The assay was linear over the concentration range of 0.500-150 ng x mL(-1) for both enantiomers (r2 > 0.99). The method was successfully applied to a stereoselective pharmacokinetic study of 100 mg desvenlafaxine sustained release tablets on 12 Chinese healthy volunteers under fasting conditions. The results showed that the pharmacokinetic parameters were similar to both enantiomers in Chinese healthy volunteers. The AUC(0-t), and C(max) of the two enantiomers were about 1.5 times higher than those of blacks and whites reported in the literature.
5.DNA Typing of Staphylococcus epidermidis with Randomly Amplified Polymorphic DNA
Meirong ZHOU ; Dafang WANG ; Rirong CHEN ; Yuxing NI
Chinese Journal of Nosocomiology 2006;0(03):-
OBJECTIVE To type Staphylococcus epidermidis and analyze its polymorphism by randomly amplified polymorphic DNA(RAPD),and provide the method for analysis of homogeneity of S.epidermidis.METHODS Twenty one collected strains from ophthalmology ward were analyzed using random primer RAPD1 with RAPD.RESULTS On the basis of bands,difference of clinical strains was analyzed.Twenty one strians of S.epidermidis were divided into 5 patterns.Among them type Ⅰ taken 71 percent(15/21).CONCLUSIONS Typing of S.epidermidis by RAPD at molecular level is very rapid,easy and reliable.It can apply to track pathogens of the hospital and study epidemiology of the bacteria.
6.Breast conserving surgery for early breast cancer: a report of 86 cases
Xianju QIN ; Houshun XU ; Wentan CHEN ; Yongkang YANG ; Dafang ZHAO
Chinese Journal of General Surgery 2001;0(08):-
ObjectiveTo evaluate the breast-conserving surgery for early breast cancer.MethodFrom 1993 to 2000, 86 female cases of stage ⅠⅡa breast cancer received breast conserving comprehensive therapy. Clinical data were analyzed retrospectively. ResultsThe 5 year survival rate of this group was 96.5% and the 5 year recurrence rate was 5.2%.The postoperative contour of the breast was satisfactory.ConclusionBreast-conserving surgery is safe and effective therapy for early breast cancer, when strict indication and necessary safe margin of resection is obeyed by. Postoperative radiotherapy and chemotherapy should be properly arranged and the patients should be closely followed-up.
7.DETERMINATION OF AMLODIPINE IN HUMAN PLASMA BY LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY
Xiaoyan CHEN ; Yan LUAN ; Dafang ZHONG ; Zongmin DU
Acta Pharmaceutica Sinica 2001;36(1):51-54
AIM To develop a sensitive and specific LC/MS/MS method for determination of amlodipine in human plasma. METHODS Amlodipine and internal standard 4′-hydroxypropafenone were extracted from plasma using liquid-liquid extraction, then separated on a Zorbax C8 column. The mobile phase consisted of acetonitrile-water-formic acid (75∶35∶1), at a flow-rate of 0.4 mL*min-1. A Finnigan TSQ tandem mass spectrometer equipped with electrospray ionization source was used as detector and was operated in the positive ion mode. Selected reaction monitoring (SRM) using the precursor → product ion combinations of m/z 409 → 238 and m/z 358 → 116 was used to quantify amlodipine and internal standard, respectively. RESULTS The linear calibration curves were obtained in the concentration range of 0.4-16.0 ng*mL-1. The limit of quantification was 0.4 ng*mL-1. Each plasma sample was chromatographed within 3.7 min. The method was successfully used in several pharmacokinetic studies for amlodipine. More than 1 500 plasma samples were assayed within two weeks. CONCLUSION The method is proved to be suitable for clinical investigation of amlodipine pharmacokinetics, which offers advantages of specificity, speed, and greater sensitivity over the previously reported methods.
8.Enantioselective determinination of R-warfarin/S-warfarin in human plasma using liquid chromatography-tandem mass spectrometry and its application in a drug-drug interaction study.
Shu JIN ; Yifan ZHANG ; Xiaoyan CHEN ; Ke LIU ; Dafang ZHONG
Acta Pharmaceutica Sinica 2012;47(1):105-9
To study the drug-drug interaction of morinidazole and warfarin and its application, a sensitive and rapid liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the determination of R-warfarin/S-warfarin in human plasma. In a random, two-period crossover study, 12 healthy volunteers received a single oral dose of 5 mg racemic warfarin in the absence and presence of morinidazole. Blood samples were collected according to a pre-designed time schedule. R-warfarin, S-warfarin and methyclothiazide were extracted with ethylether : methylenechloride (3 : 2), then separated on a Astec Chirobiotic V (150 mm x 4.6 mm ID, 5 microm) column using 5 mmol x L(-1) ammonium acetate (pH 4.0) - acetonitrile as mobile phase at a flow-rate of 1.5 mL x min(-1). The mobile phase was splitted and 0.5 mL x min(-1) was introduced into MS. A tandem mass spectrometer equipped with electrospray ionization source was used as detector and operated in the negative ion mode. Quantification was performed using multiple reaction monitoring (MRM). The resolution of warfarin enantiomers is 1.56. The linear calibration curves for R-warfarin and S-warfarin both were obtained in the concentration range of 5 - 1 000 ng x mL(-1). Intra- and inter-day relative standard deviation (RSD) for R-warfarin and S-warfarin over the entire concentration range across three validation runs was both less than 10%, and relative error (RE) ranged from -4.9% to 0.7%, separately. The method herein described is effective and convenient, and suitable for the study of metabolic interaction between morinidazole and warfarin. The results showed that coadministration of warfarin with morinidazole did not affect the pharmacokinetics of either R-warfarin or S-warfarin.
9.Predicting pharmacokinetics of anti-cancer drug, famitinib in human using physiologically based pharmacokinetic model.
Mingming YU ; Zhiwei GAO ; Xiaoyan CHEN ; Dafang ZHONG
Acta Pharmaceutica Sinica 2014;49(12):1684-8
This study is to establish physiologically based pharmacokinetic (PBPK) models of famitinib in rat and monkey, and then to predict the pharmacokinetics and tissue distribution of famitinib in human based on the PBPK models. According to published paper, previous studies and the chemical properties of famitinib predicted by ACD/ADME suite and SimCYP, the PBPK models of rat and monkey were established and optimized using GastroPlus. And then, the PBPK models were applied to predict the pharmacokinetic and tissue distribution of famitinib in human. The results showed that the PBPK models of rat and monkey can fit the observed data well, and the AUC0-∞, ratios of observed and calculated data in rat and monkey were 1.00 and 0.97, respectively. The AUC0-∞, ratios of observed and predicted data in human were 1.63 (rat to human) and 1.57 (monkey to human), respectively. The rat and monkey PBPK models of famitinib were well established, and the PBPK models were applied in predicting pharmacokinetic of famitinib in human successfully. Hence, the PBPK model of famitinib in human could be applied in future drug-drug interaction study.
10.Troubleshooting of bioinequivalence of compound valsartan tablets.
Da SHAO ; Yifan ZHANG ; Yan ZHAN ; Xiaoyan CHEN ; Dafang ZHONG
Acta Pharmaceutica Sinica 2014;49(4):524-9
The study aims to evaluate the bioequivalence of valsartan hydrochlorothiazide tablets, and to investigate the potential cause of bioinequivalence. This was a single-center study with an open, randomized double-way crossover design. Test and reference preparations containing 160 mg of valsartan and 25 mg of hydrochlorothiazide were given to 36 healthy male volunteers. Plasma concentrations of valsartan and hydrochlorothiazide were determined simultaneously by LC-MS/MS. The pharmacokinetic parameters and relative bioavailability were calculated, while the bioequivalence between test and reference preparations were evaluated. The dissolution profiles of test and reference preparations in four different mediums were determined via dissolution test and HPLC. The similarity was investigated according to the similarity factors (f2). The F(o-t) and F(0-infinity) were (139.4 +/- 65.2)% and (137.5 +/- 61.2)% for valsartan of test preparations. It led to get the conclusion that test and reference preparations were not bioequivalent for valsartan. A significant difference was observed between test and reference tablets in the valsartan dissolution test of pH 1.2 hydrochloric acid solution. The key factor of the bioinequivalence might be that dissolution of valsartan in acid medium has marked difference between two preparations.