1.Analysis of the factors effecting the expression efficiency of the green fluorescent protein gene in mouse embryonic stem cells
Hua YANG ; Jian-Xin DAI ; Xu-Ming DAI ; Ji-Liang FU
Academic Journal of Second Military Medical University 2001;22(4):319-321
Objective: To study the factors effecting the expression of the reporter green fluorescent protein (GFP) gene in the mouse embryo stem cell line R1. Methods: Three different kinds of GFP euko-expression vectors were constructed, and the expression efficiency was contrasted both at mRNA and protein levels after they were integrated into the chromosomes of host cells. Results: At protein level, the GFP expression level of the colonies transfected by the expression vector-pEF-GFP with the promoter of the peptide elongation factor (EF) were significantly higher than that of the colonies transfected by pCMV-GFP with CMV promoter and by pdCMV-GFP with double copies of CMV-GFP expression unit. There was no significant difference between the colonies transfected by pCMV-GFP and pdCMV-GFP. The detection results on mRNA level of GFP had the same tendency as that at protein level. Conclusion: (1) GFP gene expression efficiency controlled by EF promoter is distinctly higher than that by CMV promoter in NIH3T3 and R1 ES cell line.(2) A slight increase of the copy number of the foreign gene expression units in the host chromosome can not make obvious increase of its expression efficiency. (3) The vector express GFP in R1 ES cell line efficiently and stablely is obtained.
2.Analysis of the factors effecting the expression efficiency of the green fluorescent protein gene in mouse embryonic stem cells
Hua YANG ; Jian-Xin DAI ; Xu-Ming DAI ; Ji-Liang FU
Academic Journal of Second Military Medical University 2001;22(4):319-321
Objective: To study the factors effecting the expression of the reporter green fluorescent protein (GFP) gene in the mouse embryo stem cell line R1. Methods: Three different kinds of GFP euko-expression vectors were constructed, and the expression efficiency was contrasted both at mRNA and protein levels after they were integrated into the chromosomes of host cells. Results: At protein level, the GFP expression level of the colonies transfected by the expression vector-pEF-GFP with the promoter of the peptide elongation factor (EF) were significantly higher than that of the colonies transfected by pCMV-GFP with CMV promoter and by pdCMV-GFP with double copies of CMV-GFP expression unit. There was no significant difference between the colonies transfected by pCMV-GFP and pdCMV-GFP. The detection results on mRNA level of GFP had the same tendency as that at protein level. Conclusion: (1) GFP gene expression efficiency controlled by EF promoter is distinctly higher than that by CMV promoter in NIH3T3 and R1 ES cell line.(2) A slight increase of the copy number of the foreign gene expression units in the host chromosome can not make obvious increase of its expression efficiency. (3) The vector express GFP in R1 ES cell line efficiently and stablely is obtained.
3.Stability of scaphotrapeziotrapezoid novel arthrodesis apparatus
Liang TANG ; Hongxu LU ; Jian DING ; Hongsheng FANG ; Yongping DAI ; Kejian HONG
Chinese Journal of Tissue Engineering Research 2009;13(39):7651-7656
BACKGROUND: Traditional scaphotrapeziotrapezoid limited intercarpal arthrodesis contains Kirschner wire, U-shaped nail, AO/ASIF steel plate and so on. Long-term plaster external fixation was needed following surgery. USA-designed arthrodesis apparatus is mainly suitable for European and people from USA, but not fit for Asian.OBJECTIVE: To simulate scaphotrapeziotrapezoid limited intercarpal arthrodesis, and to test the stability of the novel arthrodesis apparatus developed by the group according to anatomic form of dorsal joint fovea of Chinese scaphotrapeziotrapezoid.DESIGN, TIME AND SETTING: The observational study was performed at the Laboratory of Biomechanics of the Department of Orthopaedics, Nantong University from April 2006 to March 2007.MATERIALS: A total of 40 fresh forearm samples of corpses that were not subjected to antiseptic treatment were used for this study. Radiograph verified that these samples did not develop wrist joint affection or abnormal alinement.METHODS: The cadaver models were imitated limited intercarpal instability before scaphotrapeziotrapezoid arthrodesis used circular plate. Then, simulated flexion 50°, extenion 35°, ulnar deviation 30°, radial deviation 10° ultimate activities (50000).CT scan and 3-D reconstruction should be taken before and after motion.MAIN OUTCOME MEASURES: The index of the radial-scapho angle (RSA), radial-scapho distance (RSD), scapho length(SL), trapezium-trapezoid inclination (TTI), trapezium-trapezoid width (TTW) were measured.RESULTS: Prior to motion RSA, RSD, SL, TTW and TTI were (38.725±2.230) °, (18.988±1.216) mm, (1.686±0.191) cm,(27.360±1.571) mm and (114.975±2.293) °. Following motion RSA, RSD, SL, TTW and TTI were (38.800±2.388) °,(19.215±1.443) mm, (1.683±0.209) cm, (27.718±1.910) mm, (115.300±3.023) °. No significant difference in above-described indexes was determined before and after motion (P > 0.05).CONCLUSION: The novel STT limited intercarpal arthrodesis apparatus shows confidential stability. Thus, wrist joint can do exercises in an early stage at the range of 35 dorsal extension, 50 palmar flexion, 10 radial deviation and 30 ulnar deviation.
4.Expression of hypoxia-inducible factor 1 and neuroglobin in piglet cortex during deep hypothermic circulatory arrest
Mengya LIANG ; Zhixian TANG ; Guangxian CHEN ; Jian RONG ; Gang DAI ; Zhongkai WU
Chinese Journal of Pathophysiology 2015;(5):823-827
AIM:To observe the expression of hypoxia-inducible factor 1 (HIF-1) and neuroglobin (NGB) in piglet cortex during deep hypothermic circulatory arrest.METHODS:Wuzhishan piglets were randomly assigned to car-diopulmonary bypass group ( CPB group) , 40 min of circulatory arrest ( CA) at 18 ℃ without cerebral perfusion ( DHCA group) or with selective antegrade cerebral perfusion ( SACP group) .After 180 min of reperfusion, cortical tissue was har-vested for determining HIF-1αand NGB expression by HE staining, Western blot and real-time PCR.RESULTS:Severer cerebral injury was observed in DHCA group than that in SACP group.After 180 min of reperfusion, HIF-1αprotein and mRNA levels were significantly higher in DHCA group than those in CPB group (P<0.05).Accordingly, SACP animal had higher levels of HIF-1αprotein and mRNA than those in DHCA group (P<0.05).Simultaneously, higher NGB pro-tein and mRNA levels were found in DHCA group than those in CPB group after 180 min of reperfusion ( P<0.05) .The SACP animal had higher levels of NGB protein and mRNA than those in DHCA group (P<0.05).CONCLUSION:Up-regulation of HIF-1 and NGB are involved in the mechanism against cerebral injury resulting from DHCA in the cortex and possibly a part of cerebral protective effect of SACP.
5.Optimization of Technique Conditions for Decolorization and Extract of Exopolysaccharide by Cordyceps jiangxiensis
Jian-Hui XIAO ; Dai-Xiong CHEN ; Jin-Wei LIU ; Zu-Lin LIU ; Wei-Hong WAN ; Zong-Qi LIANG ;
Microbiology 1992;0(03):-
The technique conditions of decolonization of fermentation broth were successively optimized using single factor assay and orthogonal layout method in Cordyceps jiangxiensis. The optimal condition of decolorization was investigated to be 3g/100mL active carbon, 5 min absorption time, pH5 of fermented broth and 25℃absorption temperature. Under the optimal condition, the maximum decolorization rate of fermented broth reached 89. 6% , simultaneously 10. 7% consuming rate of exopolysaccahride was minimum. Subsequently, the extract condition of exopolysaccharide of C. jiangxiensis was further optimized by orthogonal layout design. The maximum exopolysaccharide production was 0. 38 g/L under the optimal condition, i. e. firstly fermented filtrate decolorized and deproteined was concentrated to 1/7 of its total volume, secondly concentration broth was mixed with four times its volume of absolute ethanol and stirred vigorously, lastly precipitation of exopolysaccharide proceeded at 4℃for 16 hrs and the exopolysaccharide collected by centrifugal ion and dryness.
6.Disease distribution and medical resources during the Beijing 2008 Olympic and Paralympic Games.
Xue-Ya LIANG ; Ling LAN ; Wei-Na CHEN ; Ai-Ping ZHANG ; Chao-Ying LÜ ; Yan-Wei LÜ ; Jian-Ping DAI
Chinese Medical Journal 2011;124(7):1031-1036
BACKGROUNDAppropriate planning and staffing for medical services at large-scale athletic events is essential to provide for a safe and successful competition. There are few well-documented accounts describing the demand for such services. The present study provided the data from the Beijing 2008 Olympics and Paralympics, with a view to provide the guidance for planning future events.
METHODSA total of 22 029 and 8046 patients, who received medical care from a physician at an Olympic or Paralympic medical station, were included. The patient proportion among different personnel, various disease proportions at different kinds of venues, and the disease spectrum at specified venues at the Olympics and Paralympics were analyzed.
RESULTSAt both games, the patient proportion varied by accreditation status. The staff accounted for the largest number of visits at the Olympics (44.83%) and Paralympics (36.95%), with respiratory diseases the most common. Various disease spectrums were discovered at the different kinds of venues. Surgical diseases were the most frequently listed reason for visits, both at competition and non-competition venues, especially during the Paralympics. The sport-related injuries accounted for a majority of the surgical cases during both games. At training venues, ear nose and throat diseases accounted for the greatest number of visits during both games.
CONCLUSIONSDuring both games, people contracted different diseases at different venues. Adequate surgeons should be designated to offer assistance mostly in trauma situations. Appropriate numbers of physicians in respiratory diseases and otorhinolaryngology is of great importance.
Anniversaries and Special Events ; China ; Emergency Medical Services ; utilization ; Humans ; Population Surveillance ; Public Health ; statistics & numerical data ; Sports
7.Advances in the research of differentiation of embryonic stem cells into hepatocytes.
Qing-Jun ZHOU ; Jian-Zhong SHAO ; Li-Xin XIANG ; Ming ZHANG ; Yong-Liang LU ; Hang YAO ; Li-Cheng DAI
Chinese Journal of Biotechnology 2005;21(2):171-176
Orthotopic liver transplantation has proven to be effective in the treatment of a variety of life-threatening liver diseases, however, the limitations of donated organs available and long-term immunosuppression provided an impetus for developing alternative therapies. Cell replacement strategies have been one major effective approach for overcoming the obstacles of organ transplantation in recent years. The exogenous cells should be able to proliferate and differentiate into mature hepatic cells after grafting. Use of mature hepatocytes is also hampered by limited tissue source and inability to proliferate and maintain the function for a long term in vitro. Embryonic stem cells are immortal and pluripotent and may provide a novel cell source for potential cell therapy. This review summarizes the mechanisms of controlling early liver development and hepatic differentiation of visceral endoderm in embryoid bodies, and provides an overview of diverse differentiation systems in vitro and in vivo that were applied to hepatic research in recent years. Several studies have demonstrated that ES cell-derived hepatocytes can incorporate into liver tissue and function in vivo , but a few of them have shown complete restoration of liver function after transplantation into mice with liver diseases. Further studies should be made to exploit efficient methods and clinical applications of hepatocytes derived from ES cells in the future. In addition to clinical transplantation for treatment of liver diseases, ES cells can provide a valuable tool for drug discovery applications and study on of molecular basis of hepatic differentiation.
Animals
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Cell Differentiation
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physiology
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Cells, Cultured
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Embryonic Stem Cells
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cytology
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transplantation
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Hepatocytes
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cytology
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Humans
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Liver Diseases
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therapy
8.The expression of growth hormone release factor gene carried with PLGA microspheres in muscle tissue and its effect on mouse growth.
Xiao-Hui REN ; Yong-Liang ZHANG ; Song-Cai LIU ; Jian-Wei DAI
Chinese Journal of Biotechnology 2004;20(4):615-618
Injectable sustained-release pcDNA3-GRF (1-32) microspheres were prepared by double emulsion-in liquid evaporation process,using biodegrable poly lactic-co-glycolic acid as carrier. The enrapment efficiency, mean particle size, drug content thus prepared were 69%, 2.20 microm, 8% and 70% respectively. The result of transfection in vivo showed that after 30 days, accumulative increased body weights on the group injected with pcDNA3-GRF (1-32) microspheres was significantly higher than those group injected with naked plasmid (12.87%), plasmid-empty microspheres (19.72%) and saline (58.58%) respectively. PCR and RT-PCR showed that the expression level of GRF gene on the group injected with pcDNA3-GRF (1-32) microspheres was the highest. GRF gene released by microspheres was still detected after 30 days. In conclusion, pcDNA3-GRF (1-32) microspheres have a controlled release effect and GRF gene could be successfully transfected into muscle cells of mouse by microspheres with higher efficacy and stronger biological function.
Animals
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Body Weight
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DNA
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administration & dosage
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Growth
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Growth Hormone-Releasing Hormone
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genetics
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Lactic Acid
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administration & dosage
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Male
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Mice
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Microspheres
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Muscle, Skeletal
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metabolism
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Plasmids
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Polyglycolic Acid
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administration & dosage
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Polymerase Chain Reaction
9.Liquid chromatography-tandem mass spectrometry simultaneous determination of repaglinide and metformin in human plasma and its application to bioequivalence study.
Xiao-Rong LIANG ; Xiao-Jian DAI ; Yi-Fan ZHANG ; Jue-Fang DING ; Xiao-Yan CHEN ; Da-Fang ZHONG
Acta Pharmaceutica Sinica 2013;48(4):547-553
A simple, sensitive, selective, and reproducible liquid chromatography-tandem mass spectrometric method was developed for the simultaneous determination of repaglinide and metformin in human plasma using d5-repaglinide and d6-metformin as internal standards (ISs). After a simple protein precipitation using acetonitrile as the precipitation solvent, both analytes and ISs were separated on a Venusil ASB C 18 (150 mm x 4.6 mm, 5 microm) via gradient elution using acetonitrile--10 mmol x L(-1) ammonium acetate as the mobile phase. A chromatographic total run time of 7.5 min was achieved. Mass spectrometric detection was conducted with atmospheric pressure chemical ionization under positive-ion and multiple-reaction monitoring modes. The method was linear over the 0.2 to 60.0 ng x mL(-1) concentration range for repaglinide and over the 4 to 1 000 ng x mL(-1) range for metformin. For both analytes, the intra- and inter-accuracies and precisions were within the +/- 15% acceptable limit across all concentrations. The validated method was successfully applied to a clinical bioequivalence study.
Administration, Oral
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Adolescent
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Adult
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Area Under Curve
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Carbamates
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administration & dosage
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blood
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pharmacokinetics
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Chromatography, Liquid
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Drug Stability
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Female
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Humans
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Hypoglycemic Agents
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administration & dosage
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blood
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pharmacokinetics
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Male
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Metformin
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administration & dosage
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blood
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pharmacokinetics
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Middle Aged
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Piperidines
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administration & dosage
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blood
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pharmacokinetics
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Tandem Mass Spectrometry
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Therapeutic Equivalency
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Young Adult
10.p53 Anti-tumor Research in Bel-7402 by Using Human-derived Vector
Zhigang XUE ; Jian LI ; Biao YIN ; Yakun ZHANG ; Xionghao LIU ; Qian PAN ; Zhigao LONG ; Heping DAI ; Kun XIA ; Lingqian WU ; Desheng LIANG ; Jiahui XIA
Progress in Biochemistry and Biophysics 2007;34(5):465-470
In order to study the tumor suppression effect of p53 with CMV enhancer and hTERT promoter mediated by human-derived vector pHrn in liver cancer cell Bel-7402, report plasmid pchEGFP, tumor suppressor plasmids pchp53Arg and pchp53Pro were constructed by inserting expression cassette CMVe+hTERTp+EGFP, CMVe+hTERTp+p53Arg and CMVe+hTERTp+p53Pro into pHrn respectively. 24 h after cell transfection by lipofectamine 2000, GFP expression pattern was analyzed through fluorescence microscope and flow cytometry; RT-PCR and Western blot were taken to study the p53 expression pattern. The cell apoptosis by Hoechst 33258 and Annexin V-FITC/PI staining was also studied. Results show that the expression of GFP and p53 protein in Bel-7402were detected, but apparent cell apoptosis could not be found. The recombinant p53 mediated by human-derived vector could express in Bel-7402, but no significant tumor suppression effect was detected, which might result from the down regulation effect of the wild type p53 on hTERT promoter.