1.Liquid chromatography-mass spectrometry in evaluation of bioequivalence of two kinds of amlodipine besylate tablets
Chao LIANG ; Xiaohua CHENG ; Hong ZHANG ; Wenwei XU ; Xiao HU
Academic Journal of Second Military Medical University 1981;0(03):-
Objective:To establish a liquid chromatography-mass spectrometry(LC-MS) method for determining the concentration of amlodipine besylate in human plasma and to evaluate the bioequivalence of 2 kinds of amlodipine besylate tablets.Methods: Twenty healthy male volunteers were enrolled into a single crossover study.A single dose of the suspension equivalent to 10 mg amlodipine besylate or a reference preparation was given in a crossover way.The plasma concentrations of amlodipine besylate were determined by LC-MS method in the volunteers at different time points;the pharmacokinetic parameters and relative bioavailability were calculated and the bioequivalence of the 2 preparations were evaluated.Results: The pharmacokinetic parameters for experimental and the reference preparations were: C_max(6.21?1.88) vs(6.03?1.08) ng/ml;AUC_0-120(250.68?52.61) vs(246.14?52.11) ng h/ml;T_max(6.0?2.3) vs(6.1? 2.5) h;t_1/2(40.45?6.68) vs(43.74?9.05) h,respectively.The linear range of the present method was 0.1-20.0 ng/ml;the lowest detectable concentration of amlodipine besylate was 0.1 ng/ml.There was no significant difference in pharmacokinetic parameters between the 2 tablets.Conclusion: The present method is simple to use,fast,and accurate.The 2 preparations of amlodipine besylate are bioequivalent.
2.Human amniotic epithelial cells:culture technology optimization and biological characteristics
Chao LIU ; Zhiguo XU ; Shaohong WANG ; Hongling CHENG ; Xuwei YANG ; Bo GONG ; Yang LIU ; Chunyan XU
Chinese Journal of Tissue Engineering Research 2017;21(13):2100-2107
BACKGROUND:As current studies on isolation, culture andcryopreservation of human amniotic epithelial cells (hAECs) are relatively scattered, it is difficult to form a comprehensive and effective solution to meet the clinical needs of stem cells for transplantation in future.OBJECTIVE:To establish the technology of isolation, culture and cryopreservation of hAECs, and to study the biological characteristics of hAECs.METHODS:Orthogonal method was used to study the effects of different factors on the separation, culture and cryopreservation, and range method was adopted to analyze the data to optimize the separation, culture and cryopreservation. We performed cell primary and passage cultures, morphology observed by microscope, drawn cell growth curve and flow cytometry assay, immunofluorescence staining, hepatocyte like cell differentiation to study the biological characteristics of hAECs.RESULTS AND CONCLUSION:(1) The optimal hAECs separation conditions were as follows:trypsin digestions were conducted at a concentration of 0.25%, four times, once for 20 minutes digestion; optimal conditions of culture were 4×108/L cell seeding density, 10 μg/L epidermal growth factor, 5% serum; optimal conditions of cryopreservation were 1×1010/L cell cryopreservation density, 10% dimethyl sulfoxide, 80% serum. (2) The primary cells were adhered to the wall in 2-3 days, exhibiting irregular polygon, paving stone-like growth. Cell adherence and growth rate were accelerated after subculture, and the growth and proliferation ability of passage 2 cells were not significantly decreased after cryopreservation and resuscitation. (3) Immunofluorescence staining showed that the primary cells strongly expressed SSEA-4 and CK19, but did not express Vimentin, CD45 and HLA-DR. The immunophenotype statistics of the primary and passage 4 cells showed the epithelial mesenchymal transition of hAECs in culture process. (4) Immunofluorescence staining showed that the liver cell marker expression of ALB, CK18 was significantly increased after hAECs were induced to differentiate into hepatocyte-like cells. Glycogen staining revealed glycogen synthesis in hAECs after 3 weeks of induction. To conclude, hAECs are easy to obtain and have strong proliferation ability in vitro, and express surface markers for undifferentiated embryonic stem cells.
3.Culture conditions optimization and high cell density fermentation of recombinant bacteria producing heparinase II from Flavobacterium heparinum.
Bin ZHOU ; Yongmei CHENG ; Chao DENG ; Weichao LIU ; Chaoliang CHEN ; Jinghua CHEN ; Zhenghong XU
Chinese Journal of Biotechnology 2014;30(4):674-678
Heparinase II (Hep II) from Flavobacterium heparinum is an enzyme that could specifically cleave certain sequence of heparin and heparan sulfate. In this work, fermentation conditions of recombinant heparinase II (His-Hep II) producing bacteria were optimized, including initial induction time, inducer (IPTG) concentration, induction temperature and induction time. The optimum conditions were as follows: cultivating recombinant bacteria to exponential prophase under 37 degrees C, then adding IPTG to a final concentration of 0.3 g/L, finally cultivating recombinant bacteria under 20 degrees C for 10 h. The total crude enzyme activity reached 570 U/L. Based on these results, high cell density fermentation of recombinant bacteria was studied. The final OD600 could reach 98 and the total crude enzyme activity of His-Hep II increased to 9 436 U/L.
Fermentation
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Flavobacterium
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metabolism
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Microbiological Techniques
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Polysaccharide-Lyases
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biosynthesis
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Recombinant Proteins
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biosynthesis
4.An anatomical study and clinical application of free transfer of foot tissues pedicled with plantar metatarsal artery
Xiao-Chao CHU ; Cheng YANG ; Yong-Jun XU ; Qingsheng ZHU ; Rui CONG ; Hongyin DU ; Heng LI ;
Chinese Journal of Orthopaedic Trauma 2004;0(10):-
Objective To explore a new method of functional reconstruction of hand digits and joints with free transfer of foot tissues so as to increase the success rate of the operation.Methods After micro-anatomic study of the plantar and dorsal metatarsal arteries,retrograde and free grafts of foot tissues pedicled with plantar metatarsal arteries were designed and applied in transplantation to treat 76 cases of hand digital or joint defects.The surgeries included 58 cases of transfer of the second toe,four cases of transfer of composite tissues of the second toe, eight cases of transfer of proximal interphalangeal joint,and six cases of nail flap transfer.Results The mi- cro-anatomic study found that the first plantar metatarsal artery was anatomically constant and the diameter of its branch to the second toe was larger than that of the first dorsal metatarsal artery.Flaps survived in 75 of the 76 patients(98.7%),with fine appearance and significantly improved function.One patient who had received free transfer of the second toe to reconstruct the thumb function had to undergo a second repair with infraclavicula skin tube because of refractory arteriospasm of anastomosed vessels.Conclusion Transfer with free retrograde grafts of foot tissues pedicled with plantar metatarsal artery to reconstruct hand functions can effectively improve the success rate of the operation,because it is free of the shortcomings of great anatomic variation of blood vessels and time-consuming and complex procedures in conventional transfer.
5.Establishment of Loop-mediated Isothermal Amplification (LAMP) Method for Campylobacter jejuni Detection
Chao LIN ; Cheng-Zhu LIANG ; Biao XU ; Min SUN ; Cai-Xia LIU ; Hong-Wei GAO ;
Microbiology 1992;0(06):-
A rapid LAMP detection method with primers designed on genus-specific region identified in the gyrA gene was established in this assay. All four Campylobacter jejuni from different sources were detected positive and fourteen non Campylobacter bacteria were negative, which shows excellent specificity of the primers. Compared with plate count and PCR method, the LAMP method and the PCR method had equal sensitivity, which were three orders of magnitude higher than plate count. In this assay, we also found out that the treatment of DNase could reduce the dead bacteria DNA effectively. The LAMP detection on chicken indicated relatively good result on detection of Campylobacter jejuni combining with treatment of DNase.
6.Differentiation of mouse embryonic stem cells into insulin-secreting cells induced by a 5-step model system
Mu-Chao WU ; Hua CHENG ; Ming-Tong XU ; Li-Hong CHEN ; Feng LI ; Sheng-Neng XUE ;
Chinese Journal of Endocrinology and Metabolism 1986;0(03):-
Objective To induce mouse embryonic stem(ES)cells to differentiate into insulin-secreting cells by means of a 5-step model system.Methods E14.1 mouse ES cells were cultured in the presence of leukemia inhibitory factor(LIF)for 2 days(step 1),then the cells were cultured in hanging drops to form embryonic bodies(EBs)and the resulting EBs were cultured in suspension for 6 days in the presence of basic fibroblast growth factor bFGF(step 2).Subsequently the EBs were cultured in the medium containing glucagon- like peptide 1(GLP-1),hepatocyte growth factor(HGF),nerve growth factor(NGF)and nicotinamide for 10 days(step 3).After that,the EBs were dissociated into single cells,and the cells were cultured in monolayer in the presence of GLP-1,betacellulin,activin A,bFGF and nicotinamide for 10 days(step 4).Finally,the cells were cultured in low-glucose medium containing nicotinamide for 4 days(step 5).Insulin and some other islet- related genes expressions were investigated using RT-PCR and insulin expression was also investigated by DTZ- staining and immunohistochemistry.The percentage of insulin-secreting cells was evaluated by flowcytometry and insulin concentrations were measured by RIA.Results mRNA expression of insulin became visible at step 3 and more evident at step 5.Additionally,at step 5,mRNAs of glucagon,somatostatin,pancreatic polypeptide(PP), pancreatic duodenal homeobox 1(PDX-1),beta-cell E box transactivator 2(Beta2)and neurogenin 3(Ngn3) were detected.DTZ-staining positive cells and insulin immunohistochemical staining positive cells were observed. The percentage of insulin-positive cells was(24.0?2.5)%(n=6).In the presence of 5.6 mmol/L and 25 mmol/L glucose,insulin concentrations were(0.05?0.01)?g/L and(0.13?0.02)?g/L respectively(n= 6).Conclusion E14.1 mouse ES cells can be induced to differentiate into insulin-secreting cells by the 5-step model system.Insulin-secreting cells can release insulin into culture medium when treated with glucose,and insulin concentrations increase with rising concentration of glucose.
7.Immunoregulation study of UCMSCs on UCB CD4+T lymphocytes in vitro
Bo GONG ; Zhiguo XU ; Shaohong WANG ; Hongling CHENG ; Chao LIU ; Mingjie YAN
Chinese Journal of Immunology 2017;33(2):220-225
Objective:Immunoregulation study of umbilical mesenchymal stem cell (UCMSCs) on allogeneic umbilical cord blood(UCB) CD4+T lymphocytes,which proliferation,apoptosis and the differentiation to CD4+CD25+ regulatory T cell (Treg) in vitro. Methods:Establishing on direct contact or transwell co-culture system,adopt in different proportion of UCMCs with phytohaemag-glutinin (PHA)-activated UCB CD4+T lymphocytes were co-cultured. The proliferation of lymphocyte,percent of CD4+CD25+/CD4+and Foxp3 expression, regulatory T cell marker gene were measured. Apoptosis of CD4+T lymphocytes were observed in the direct contact or transwell coculture system of UCMSCs with desamethason( DXM)-stimulated UCB CD4+T lymphocytes. Results: The UCB CD4+T lymphocytes cocultured with UCMSCs with PHA-activating for 3 days,compared with the UCMSCs free control group,the amount of cells was reduced noticeably(P<0. 05) and the percent of CD4+CD25+in CD4+T lymphocytes and Foxp3 expression significantly in-creased(P<0. 01) in a dose dependent way(P<0. 05). The UCB CD4+T lymphocytes cocultured with UCMSCs with DXM-inducing for 7 days,the apoptosis rate was significantly lower than that of the control group without UCMSCs (P<0. 01). These effects were partially attenuated in transwell coculture but could not be eliminated. Conclusion: UCMSCs are negative effect on UCB CD4+T lymphocytes-mediated immunity effects,and mainly manifested in the regulation on cell proliferate ability and differentiation rather than promoting apoptosis.
8.Gene Detection of GPD1-L and the Association with Sudden Unexplained Death Syndrome in Young Adults
Xiaolong XU ; Wen WANG ; Chao LIU ; Yiding HOU ; Lei HUANG ; Changhui LIU ; Yue LI ; Jianding CHENG
Journal of Forensic Medicine 2013;(5):348-352
Objective To analyze the variations of glycerol-3-phosphate dehydrogenase 1 like gene (GPD1-L) and address the association with sudden m anhood death syndrom e (SMDS). Methods The genom ic DNA was extracted from blood sam ples of the SMDS group and the norm alcontrolgroup.The exons, exon-in-tron boundaries and 3′-U TRs of coding region of GPD1-L w ere PCRam plified and DNAsequenced di-rectly to confirm the types of variations. The genotype frequency and allele frequency w ere analyzed statistically. Results There w ere tw ovariants in the SMDS group, c.465C>Tand c.*18G>T, the latter existed certain degree difference of genotype distribution and allele frequency betw een the SMDS group and the control group, but there was no statistically significant (P>0.05). Conclusion The relation be-tw een gene m utation of GPD1-L and the occurrence of Chinese SMDS deserves a further research.
9.Research status on quality of life in patients with aneurysmal subarachnoid hemorrhage
Linlin ZHU ; Rui BIAN ; Chao CHENG ; Hao YUAN ; Hui WANG ; Yousong XU
Chinese Journal of Postgraduates of Medicine 2016;39(6):570-573
Aneurysmal subarachnoid hemorrhage accounted for 70% of subarachnoid hemorrhage. The high fatality and disability rate affected patients′ quality of life. Aneurysmal subarachnoid hemorrhage should be considered as a chronic cerebrovascular disease, and it is very important to take early intervention and strengthen the secondary prevention to the patients with risk factors for disease. This paper reviewed the research status on quality of life of patients with aneurysmal subarachnoid hemorrhage and its influencing factors, in order to provide a reference for neurological physicians.
10.The value of 131Ⅰ SPECT/CT in differentiating indeterminate 131Ⅰ uptake on planar whole body scan
Min, XU ; Ying-sheng, CHENG ; Han-kui, LU ; Yun-chao, GAO
Chinese Journal of Nuclear Medicine 2011;31(4):227-229
Objective To evaluate the clinical value of 131 Ⅰ SPECT/CT in the differentiation of indeterminate 131Ⅰ uptake on planer whole body scan (WBS) for patients with DTC after 131Ⅰ treatment. Methods Fifty-six DTC patients ( male: 19, female: 37, mean age: 45 ± 15 years, ranging from 20 to 85 years) underwent 131Ⅰ treatment. 131Ⅰ WBS was performed five days after 131 Ⅰ treatment, followed by regional 131Ⅰ SPECT/CT for the indeterminate foci with abnormal uptake on 131Ⅰ WBS. The diagnostic difference of the two imaging modalities was compared by x2 test. Results There were 288 foci with abnormal uptake on 131 Ⅰ WBS, including 108 indeterminate foci (37.5%). Subsequent 131Ⅰ SPECT/CT identified 27 foci as DTC metastases (25.0%) and 71 foci as non-metastases such as benign lesions at nose, oral cavity, salivary gland, maxillary cyst, thyroid remnant, thymus, gallbladder, gastrointestinal tract, and uterus, or non-specific uptake of body contaminations (65.7%). However, the remaining 10 foci (9.3%) remained indeterminate on 131 Ⅰ SPECT/CT imaging. The diagnostic accuracy of 131 Ⅰ SPECT/CT was significantly higher than that of 131Ⅰ WBS (x2 = 102.35, P<0. 01). Conclusion 131Ⅰ SPECT/CT could significantly improve the diagnostic accuracy for the differentiation of indeterminate foci with abnormal uptake on 131Ⅰ WBS.