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.Prevalence of fatty liver in a district of Shanghai detected by B-type ultrasonography and serum activity of alanine aminotransferase
Xiao-Bo CAI ; Jian-Gao FAN ; Jun ZHU ; Xin-Jian LI ; Rui LI ; Fei DAI ;
Chinese Journal of General Practitioners 2005;0(10):-
Objective To study the prevalence of fatty liver and its risk factors in adult population of Pudong New District,Shanghai detected by combination of B-type uhrasonographic features and elevated serum activity of alanine aminotransferase (ALT).Methods A cross-sectional survey was performed in 2017 residents aged 16 years over recruited from four neighborhoods of Prdong New District of Shanghai with multi-phase cluster sampling,including interview with questionnaire,physical check-up,anthropometry, measurement of plasma glucose and lipid profile,ALT activity and real-time B-type ultrasnnography.Serum hepatitis B surface antigen (HBsAg) was further detected for those with elevated ALT activity.Results Prevalence of fatty liver was 21.32 percent (430/2017) in the residents of the District participated in this survey.Prevalence of abdominal obesity,hypertriglyceridemia,hyperlipoproteinemia (low-density lipoprotein-cholecterol),essential hypertension,impaired glucose tolerance,diabetes and metabolic syndrome were 71.16,71.16,11.86,66.74,35.58,24.40 and 47.21 percent in those with fatty liver, respectively,as compared to 26.34,12.73,4.79,39.57,24.01,6.81 and 11.28 percent in those without fatty liver (controls),respectively.Multivariate logistic regression analysis showed that body mass index, 2-h postprandial glucose level,diastolic blood pressure,serum level of triglyceride,abdominal obesity and diabetes all were independent risk factor for tatty liver,with odds ratio (OR) of 1.080,1.149,1.035, 1.526,1.960 and 1.391,respectively.Conclusions Prevalence of fatty liver was relatively high in Shanghai Pudong New District.Fatty liver closely associates with disturbance of carbohydrate and lipid metabolism.
4.Establishment and application of a genotyping technique for detection of different DNA regions in Yersinia pestis using multiple polymerase chain reaction
Xiaoyan YANG ; Youquan XIN ; Juan JIN ; Yong JIN ; Jian HE ; Ruixia DAI ; Zhizhen QI
Chinese Journal of Endemiology 2016;35(6):463-467
Objective By the method of multiple polymerase chain reaction (PCR),we intend to amplify different regions (DFR) of Yersinia pestis DNA,and to establish a multiple DFR genotyping technique for detection of Yersinia pestis.Methods According to the product size of 23 DFRs and pMT plasmid,24 primers were optimized and combined,then multiple primers in one PCR reaction system were added,and positive template DNA was amplified.Meanwhile,200 wild strain DNAs were amplified by multiple PCR and normal PCR,to verify the coincidence rate of the two methods.Results Totally 24 target segments were amplified through the positive DNA template.Through different permutation and combination,24 primers were optimized and combined into 9 groups.Totally 200 wild strain DNAs were used for verification,the coincidence rate of multiple PCR and normal PCR was 100%.Conclusions Multiple PCR is applicable and feasible for DFR genotyping of Yersinia pestis.It is an efficient,economic and high accuracy experimental method for large quantities of Yersinia pestis DFR genotyping.
5.The effect of local mild hypothermia on MMP-2/9 expression and brain edema in experimental intracerebral hemorrhage in rats
Jian-Ping ZHANG ; Fan-Chao MENG ; Ji-Wen DAI ; Xin-Yan ZHANG ;
Chinese Journal of Physical Medicine and Rehabilitation 2003;0(10):-
Objective To study the effect of local mild hypothermia on the expression of matrix metallopro- teinases-2/9 (MMP-2/9) and brain edema in experimental intracerebral hemorrhage (ICH) in rat. Methods One hundred and forty-five Wistar rats were randomly divided into a normothermia sham-operation (NSO) group ( n = 15 ), a normothermia intracerebral hemorrhage (NICH) group (n = 75 ) and a mild hypotbermia intracerebral hemor- rhage (MHICH) group (n = 75). Autologous arterial blood was stereotaxically injected into the right caudate nucleus of the rats of the NICH and MHICH groups to make intracerebral hemorrhage model. The rats in the MHICH group were then subjected to 4 hours of local mild hypothermia, while those in the NICH group were under the room temper- ature. The brain water content, permeability of brain-blood barrier (BBB) and expressions of MMP-2/9 were meas- ured by immunohistochemistry method at 6 h, 24 h, 72 h, 5 d and 7 d after operation. Results In NICH group, the brain water content, permeability of BBB and expression of MMP-9 all began to increase at 6 h and peaked at 3 d after injection of blood and still higher than the NSO group at 7 d. The expression of MMP-2 only began to increase little at 24 h and peaked at 5 d after operation and remained highly expressed at 7 d. In the MHICH group, the chan- ges of brain water content, permeability of BBB and expression of MMP-9 were similar to those of the NICH group, but the extent of changes was significantly lower at the every time point. In NICH group and MHICH group, MMP-9 expression was positively correlated with both the brain water content and the permeability of BBB, but MMP-2 ex- pression was not correlated with them. Conclusion Mild hypothermia might protect BBB against injury caused by ICH and relieve brain edema and inflammation reaction through inhibiting the expression of MMP-2/9.
6.Preparation of 99Tcm labeled survivin mRNA antisense PNA and gene imaging in nude mice bearing lung carcinoma A549 xenografts
Xin-ming, ZHAO ; Meng, DAI ; Ya-li, LIU ; Jian-fang, WANG ; Jing-mian, ZHANG ; Ying-chen, WANG ; Zhao-qi, ZHANG ; Chun-nuan, DAI ; De-zhi, LI
Chinese Journal of Nuclear Medicine 2011;31(5):339-343
Objective To prepare the 99Tcm-survivin mRNA antisense peptide nucleic acid (PNA)and investigate its value as a gene imaging agent in tumor bearing mice and early diagnosis in tumor.Methods Survivin mRNA antisense PNA and mismatch PNA were synthesized.Four amino acids (Gly- (D)Ala-Gly-Gly) and Aba (4-aminobutyric acid) were linked to the 5' end of PNA.Gly- (D)Ala-Gly-Gly served as a chelating moiety for strong chelation of 99Tcm and Aba acted as a spacer to minimize the steric hindrance.PNAs were labeled with 99Tcm by the ligand-exchange method.The labeling efficiency and radiochemical purity were measured by HPLC and ITLC methods.There were five BALB/c nude mice bearing human lung carcinoma ( A549 ) in each of antisense PNA and mismatch PNA groups.Gene imaging of 99Tcm-survivin mRNA antisense and mismatch PNAs were performed at 1,2 and 4 h post the injection,respectively,and the T/NT ratio was measured by the method of ROI.The statistical comparisons of average values were performed with the two-group t-test for independent sample by SPSS 13.0.Results The product kept stable in vitro.The labeling efficiency of 99Tcm-survivin mRNA antisense PNA was (95.48 ±1.92)% and more than 85% after the incubation for24 h in serum.The radiochemical purity was > 95%.The labeling efficiency of mismatch PNA was similar to the antisense PNA.99Tcm-survivin mRNA antisense PNA was especially uptaken by tumor lesion,and its accumulation reached the top at 4 h post the injection.T/NT ratios at 1,2,and 4 h were 2.70 ± 0.28,3.44 ± 0.35,4.21 ± 0.63,respectively.In the comparison,the T/NT ratio of 99Tcm-survivin mRNA mismatch PNA at 4 h (3.12 ±0.50) was significantly lower (t =2.918,P =0.019).Conclusions 99Tcm-survivin mRNA antisense PNA has high labeling efficiency,good stability and no need of purification.Its characteristic of especial uptake by tumor lesion provides the potential value in early diagnosis of tumor.
7.Diagnostic values of ultrasound and (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography/computerized tomography for patients with suspected thyroid carcinoma and lymph node metastasis.
Xing-jian LAI ; Bo ZHANG ; Yu-xin JIANG ; Qing DAI ; Rui-na ZHAO
Acta Academiae Medicinae Sinicae 2013;35(4):393-397
OBJECTIVETo evaluate the diagnostic values of ultrasound (US) and (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG PET)/computerized tomography (CT) in diagnosing suspected thyroid carcinoma and lymph node metastasis.
METHODSThe clinical data of 28 patients who had undergone total or subtotal thyroidectomy with or without neck dissection from December 2011 to December 2012 in PUMC Hospital and had undergone US and FDG PET/CT before surgery were retrospectively analyzed. In each patient, US and FDG PET/CT images were retrospectively reviewed to determine the presence of carcinoma with or without loco-regional metastasis by level-by-level analysis. The potential correlation between imaging results and histopathology were analyzed.
RESULTSThere were 11 benign lesions,15 papillary carcinomas, one follicular carcinoma, and one medullary carcinoma. For thyroid carcinoma,the sensitivity and specificity were 88.2% and 63.6% for US and 76.5% and 54.5% for FDG PET/CT(P>0.05). For lymph node metastasis, the sensitivity was 68.0% for US and 60.0% for FDG PET/CT (P>0.05), and the specificity was 96.7% for US and FDG PET/CT.FDG PET/CT could provide more diagnostic information than US for patients with level 2 or 5 metastasis.
CONCLUSIONSCombination of US and FDG PET/CT is typically not needed for differentiating thyroid lesions.However, for patients with suspected lymph node metastasis of infrequently involved levels, the combination of US and FDG PET/CT may be a good choice.
Adolescent ; Adult ; Aged ; Female ; Fluorodeoxyglucose F18 ; Humans ; Lymph Nodes ; pathology ; Lymphatic Metastasis ; diagnosis ; Male ; Middle Aged ; Positron-Emission Tomography ; Retrospective Studies ; Sensitivity and Specificity ; Thyroid Neoplasms ; diagnostic imaging ; Tomography, X-Ray Computed ; Ultrasonography ; Young Adult
8.Introduction of fluorescence molecular imaging technology and its development.
Xin-Jian ZHU ; Xiao-Lei SONG ; Dai-Fa WANG ; Jing BAI
Chinese Journal of Medical Instrumentation 2008;32(1):1-25
In vivo fluorescence molecular imaging plays a more and more important role in the observation of diseases, drug research and biology research because of its low cost, simplicity and no ionizing radiation to biological tissue. Herein, the most important parts of the optical fluorescence molecular imaging and their advances are summarized, including fluorescent molecular probes, imaging systems and reconstruction algorithms. The application and development trend of this technology are also introduced in this paper.
Algorithms
;
Fluorescent Dyes
;
Molecular Imaging
;
methods
9.Studies on drug and disinfectant resistance related genes of Yersinia pestis in China
Ruixia DAI ; Jian HE ; Xiaoyan YANG ; Youquan XIN ; Sheng LI ; Juan JIN ; Qi ZHANG ; Jixiang BAI ; Baiqing WEI
Chinese Journal of Endemiology 2021;40(1):27-31
Objective:To understand whether there are drug resistant and disinfectant resistant Yersinia pestis strains in China, and to provide accurate information for clinical treatment of plague. Methods:A total of 2 753 Yersinia pestis strains isolated from 10 natural plague foci in China from 1943 to 2016 were collected. According to National Center for Biotechnology Information (NCBI) released sequences of aminoglycoside streptomycin resistant genes strA, strB, β-lactam antibiotics resistant genes TEM, SHV and CTX-M, sulfamilamide resistant genes sul1, sul2 and sul3, and disinfectant resistant gene qacE△1-sul1, a pair of primers of each gene was designed for above-mentioned genes. Genomic DNA of 2 753 strains of Yersinia pestis was extracted, and the 9 target genes of all DNA samples were amplified by PCR. Results:Negative and positive controls of PCR detection were established. No corresponding target bands of aminoglycoside streptomycin resistant genes strA, strB, β-lactam antibiotics resistant genes TEM, SHV and CTX-M, sulfamilamide resistant genes sul1, sul2 and sul3, and disinfectant resistant gene qacE△1-sul1 were found in the DNA samples of 2 753 strains of Yersinia pestis.Conclusion:The above-mentioned genes of drug resistance and disinfectant resistance have not been detected in Yersinia pestis of China, but the monitoring of drug resistance of Yersinia pestis still needs to be carried out continuously.
10.Drug resistance of Yersinia pestis in natural foci of plague in Inner Mongolia Autonomous Region
Juan JIN ; Youquan XIN ; Sheng LI ; Xiaoyan YANG ; Jian HE ; Qi ZHANG ; Jixiang BAI ; Hanqing YANG ; Haoming XIONG ; Ruixia DAI
Chinese Journal of Endemiology 2021;40(4):279-282
Objective:To investigate the drug resistance of Yersinia pestis to 11 kinds of antibiotics in the natural foci of plague in Inner Mongolia Autonomous Region, and to provide a theoretical basis for scientifically and effectively selecting antibiotics for treatment of the plague. Methods:A total of 137 strains of Yersinia pestis isolated from the natural foci of plague in Inner Mongolia Autonomous Region at different times, regions, hosts and vectors were collected. According to Clinical and Laboratory Standard Institute (CLSI), the agar plate dilution method was used to determine the minimum inhibitory concentration (MIC) of the 11 kinds of antibiotics against 137 strains of Yersinia pestis, including ofloxacin, ciprofloxacin, kanamycin, streptomycin, ceftriaxone, ampicillin, chloramphenicol, spectinomycin, cefuroxime, tetracycline and sulfamethoxazole-trimethoprim. The MIC 50 and MIC 90 (the minimum concentration of drug which could inhibit 50% and 90% of bacterial growth) were calculated, and their sensitivity was determined according to CLSI standards. Results:Among 137 strains of Yersinia pestis tested, no strains of Yersinia pestis had single or multiple resistance to ofloxacin, ciprofloxacin, kanamycin, streptomycin, ceftriaxone, ampicillin, chloramphenicol, spectinomycin, cefuroxime, tetracycline and sulfamethoxazole-trimethoprim. According to CLSI standards, 137 strains of Yersinia pestis were all sensitive to the 11 kinds of antibiotics; among them, ofloxacin, ciprofloxacin, ceftriaxone and sulfamethoxazole-trimethoprim had higher antibacterial activity, with MIC 90 < 0.250 μg/ ml; the antibacterial activity of spectinomycin was the lowest, with MIC 90 of 16.000 μg/ml. Conclusions:The Yersinia pestis isolated from the natural foci of plague in Inner Mongolia Autonomous Region is not found to have single or multiple resistance to the 11 kinds of antibiotics. Continuous drug resistance monitoring of Yersinia pestis should be carried out to provide a basis for clinical medication.