1.Quantification of sitagliptin in human plasma and urine by LC-MS/MS method and its application.
Qian ZHAO ; Bo-ya WANG ; Ji JIANG ; Pei HU
Acta Pharmaceutica Sinica 2015;50(6):714-718
A rapid and sensitive liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method for quantification of sitagliptin in human plasma and urine had been developed. This method was applied to the pharmacokinetics study of sitagliptin tablet after single- and multiple-dosing in Chinese population. Plasma samples were prepared by a liquid-liquid extracted method, and urine samples were diluted. Compounds were analyzed by multiple reaction monitoring (MRM) mode with a electrospray ionization (ESI) interface. Mobile phase consisted of methanol and water (85 : 15, v/v). The linear concentration range of calibration curve was 0.5-1 000 ng.mL-1. and 0.2-100 µg.mL , intra-run/between-run accuracy was 98.98%-103.69% and 97.63%-102.29%, intra-run/between-run precision was <5.51% and 4.26% for plasma and urine sample, respectively. The stability of sitagliptin stock solution was tested for 55 days at -30 °C. Sitagliptin was stable when stored under the following conditions: 24 hours in the autosampler after sample preparation; 24 hours at room temperature, after 3 freeze and thaw cycles (from -30 °C to room temperature), 40 days at -30 °C for plasma and urine samples. The absolute recovery in plasma was 71.1%, and no matrix effect was founded. This method was proved simple, specific, sensitive, rapid and suitable for pharmacokinetics study of sitagliptin in human being.
Calibration
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Chromatography, Liquid
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Humans
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Liquid-Liquid Extraction
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Sitagliptin Phosphate
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blood
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pharmacokinetics
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urine
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Tandem Mass Spectrometry
3.Speckle-tracking imaging and tissue Doppler strain imaging in assessing left atrium mechanical function: A study on patients with transcatheter device closure of atrial septal defect
Fang FANG ; Zhian LI ; Ya YANG ; Jinfeng PEI ; Shurong LUAN
Chinese Journal of Medical Imaging Technology 2010;26(4):659-661
Objective To compare the value of speckle-tracking imaging and tissue Doppler strain imaging in evaluating left atrial (LA) mechanical contraction. Methods Forty patients after successful percutaneous atrial septal defect (ASD) closure were enrolled in this study. Two-dimensional strain imaging (2D strain echocardiography, 2DSE) and tissue Doppler imaging (TDI) were performed one weak after ASD closure. Off-line analysis was done for atrial longitudinal peak systolic strain on the interatrial septum, in correspondence of the device, and on the lateral wall of the left atrium from apical 4 chamber view with 2DSE and color-coded strain imaging, respectively. Results There was no statistical difference of the inter- and intra-observer viability as well as time consumption on the off-line analysis between 2DSE and TDI. LA lateral wall strain was much higher than that of LA septum assessed by both color-coded strain imaging (47.31%±27.25% vs 30.06%±14.29%, P<0.01) and 2DSE (43.49%±25.55% vs 12.74%±9.16%, P<0.001). LA lateral wall strain was similar with either method (P=NS). However, at the site of ASD occluder, a non-contractile element, deformation was significantly higher in color-coded strain imaging than 2DSE (P<0.001). Five patients (12.50%) presented absence of deformation on ASD occluder with 2DSE, whereas there was no patient with TDI assessment (χ~2=5.33, P=0.027). Conclusion Speckle-tracking imaging is superior to tissue Doppler strain imaging in assessing left atrium mechanical function.
4.Relation of visual field defect with pupil in patients with primary open angle glaucoma
Qiong, ZHANG ; Xiao-Lei, LU ; Ya-Pei, YANG
International Eye Science 2016;16(8):1498-1500
Abstract?AIM:To evaluate the pupil light reflex in patients with primary open angle glaucoma, and to investigate the relation between pupil and visual field defect.?METHODS:From July 2014 to October 2015, 115 eyes in 86 patients with primary open angle glaucoma and 23 eyes in 16 healthy individuals were continuously enrolled in this study.All the subjects received comprehensive eye examination, visual field examination ( Humphrey, SITA Standard 24-2 ) and dynamic pupil measurement ( MonCV3 Metrovision) .According to the visual field and the Glaucoma Staging System, the patients with glaucoma were divided into 5 subgroups: stage 1, stage 2, stage 3, stage 4 and stage 5. The parameters of pupillary light reflex were as follows: pupil diameter ( minimum, maximum ) , latency and duration of contraction, latency and duration of dilatation, contraction amplitude, contraction and dilatation speed, and percent of pupil contraction ( PPC ). SPSS 19.0 statistical software was used to analyze the measurement results.?RESULTS:The control group significantly differed from the stage 4 subgroup ( P=0.032 ) and stage 5 subgroup (P=0.014) in terms of minimum pupil diameter; there was significant difference in the pupil contraction speed between groups ( F =648.675, P <0.01 ), and the contraction speed in stage 5 subgroup was significantly lower than those in the other subgroups and control group (P<0.05); the control group significantly differed from the stage 3, stage 4, and stage 5 subgroup in terms of PPC ( P<0.05 ).Pupil contraction speed, PPC and minimum diameter showed correlation with the stages of glaucoma.?CONCLUSION:Pupil contraction ability in patients with primary open angle glaucoma was impaired, and the degree of impairment is related with the degree of visual field defect.
5.Cloning and Alignment of the Partial Mannanase Gene of Bacillus spp
Ya-Nan LI ; Kun MENG ; Pei-Long YANG ; Ya-Ru WANG ; Bin YAO ;
Microbiology 1992;0(01):-
By functional plates,16 strains which can produce?-mannana-se were isolated frnm 28 Bacillus spp.Using a pair of degenerated primers,the conserved fragments of?-mannanase gene from the selected strains were amplified by PCR.The obtained nucleotide fragments were sequenced and compared with the homologous?-mannanase genes in GenBank and a phylogenetic tree was generated.Comparing to the genes coding?-mannanase published,the cloned nucleotide fragments show the highest sequence identity between 62% and 98%.The genes coding fnr?-mannanase of Bacillus circulus have low identity while the?-mannanase genes of Bacillus subtilis and other Bacillus spp. have high identity.
8.Inhibition effect of volatile of alkyd color lacquer on superoxide dismutase in multiple organs of mice.
Wen-hua SONG ; Ru-yan MA ; Ya-tuo PEI
Chinese Journal of Industrial Hygiene and Occupational Diseases 2007;25(7):413-414
Animals
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Hydroxy Acids
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toxicity
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Lacquer
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toxicity
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Mice
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Mice, Inbred ICR
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Superoxide Dismutase
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metabolism
9.Expression of cell cycle regulator ATM, Chk2 and p53 and their clinicopathological correlation in breast infiltrative ductal carcinoma.
Xiao-juan PEI ; Qing-xu YANG ; Shao-jie LIU ; Min SU ; Zhuo-ya HUANG ; An-jia HAN
Chinese Journal of Pathology 2012;41(7):479-480
Ataxia Telangiectasia Mutated Proteins
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Breast
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metabolism
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pathology
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Breast Neoplasms
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metabolism
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pathology
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Carcinoma, Ductal, Breast
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metabolism
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pathology
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Carcinoma, Intraductal, Noninfiltrating
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metabolism
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pathology
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Cell Cycle Proteins
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metabolism
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Checkpoint Kinase 2
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DNA-Binding Proteins
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metabolism
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Female
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Humans
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Lymphatic Metastasis
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Neoplasm Grading
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Protein-Serine-Threonine Kinases
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metabolism
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Tumor Burden
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Tumor Suppressor Protein p53
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metabolism
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Tumor Suppressor Proteins
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metabolism
10.Retrospective analysis of echocardiography on criss-cross heart
Fang FANG ; Zhian LI ; Jinfeng PEI ; Kaichu LAU ; Ya YANG ; Lin SUN ; Shurong LUAN ; Wenxu LIU
Chinese Journal of Ultrasonography 2008;17(8):665-667
Objective To describe the characteristics of the criss-cross heart with comprehensively segmental echocardiographic scanning in order to explore the diagnostic value of the echocardiography.Methods Ten cases of criss-cross heart were retrospectively reviewed with 2-dimensional,color Doppler echocardiography to summarize the main diagnostic methods.Results The right ventricle was located superiorly and the left ventricle inferiorly in 9 patients and paralleled alignment in 1.The solitus situs was observed in 9 patients and dextrocardia in 1;the atrioventricular connections were concordant in 8 patients and discordant in 2.Echocardiography revealed that 5 patients presented with transposition of great artery and 5 with double outlet of right ventricle as well as all with ventricular septum defect.Conclusions Clear visualization is available with echocardiography to show the crossing inflow streams at the level of atrial-ventricular valve,abnormal alignment of the ventricular septum as well as the associated abnormalities.