2.Development and Optimization of Method for Generating Unmarked A. tumefaciens Mutants
Minliang GUO ; Qing ZHU ; Diankun GAO
Progress in Biochemistry and Biophysics 2009;36(5):556-565
Agrobacterium tumefaciens possesses many advantages as a model bacterium for the study of a wide variety of biological processes. Gene disruption or inactivation is a powerful and direct tool for investigation of in vivo gene functions. The intensive study ofA. tumefaciens has increased the need for simple and highly efficient procedures to manipulate its genome. The sacB gene was used as a counterselectable marker to develop a gene replacement procedure that allows precise insertion, deletion, and allele substitution of any gene sequence in A. tumefaciens without altering the genome in any other way. A kanamycin resistance (KmR) cassette was constructed to the suicide vector as the positive selection marker. The suicide plasmid containing DNA fragments homologous to the flanking sequences of the target gene was integrated into the recipient cell genome at the target gene locus by intermolecular homologous recombination, generating the KmR-single cross-over colonies. The effect of homologous sequence length on the intermolecular homologous recombination was analyzed. The second cross-over colonies generated by intramolecular homologous recombination occurring between two tandem repeats were simply screened out by counter-selection of sacB. Data showed that the intervening sequence length between two repeats significantly affected the intramolecular homologous recombination frequency in A. tumefaciens, indicating that A. tumefaciens adopted the homologous recombination mechanism similar to that in E. coli. All these results demonstrated that investigators could minimize the numbers of colonies to be analyzed and reduce the overall workload by optimizing the relative length of two homologous fragments and using the specific type of single cross-over transformants for screening the second cross-over event. This mutagenesis strategy had successfully been used to generate the double unmarked △vbp2△vbp3 mutant in two A. tumefaciens strains.
3.Influence of interleukin-11 on graft versus host disease and graft versus leukemia after allogenic bone marrow transplantation in acute lymphoblastic leukemic junior rats
Journal of Applied Clinical Pediatrics 1992;0(06):-
Objective To study the influence of interleukin-11 (IL-11) on graft versus host disease(GVHD) and graft versus leukemia(GVL) after allogenic bone marrow transplantation and related mechanism in acute lymphoblastic leukemic(ALL) junior mice.Methods The impact of IL-11 on CD4 and CD8 T cell after transplantation was evaluated by flow cytometry;it was observed that the GVHD pathology chance of internal after transplatation in ALL junior mice;the survial time after transplantantion was recorded;the level of tumor necrosis factor-?(TNF-?) which evidently related to GVHD was evaluated by ELISA.Results IL-11 could decrease the quantity of CD4 T cell and increase CD8 T cell;IL-11 could obviously increase the survival time and decrease the level of TNF-?. After ALL junior mice transplatated,IL-11 could delay and relieve GVHD.Conclusion IL-11 can alleviate GVHD and retain the effect of GVL after allogenic bone marrow transplantation.
4.Experimental study on arsenic trioxide-induced apoptosis of human pan creatic cancer cell line
Yong GAO ; Jiejun WANG ; Qing XU ; Jing GUO ; Shaochang JIA
Academic Journal of Second Military Medical University 2001;22(1):43-46
Objective: To study the effect of arsenic trioxide (As2O3) on human pancreatic cancer cell proliferation and apoptosis (mainly early stage) in vitro. Methods: SW1990 cells line were trea ted with As2O3 at different concentration. Cell proliferation was evaluated by MTT and apoptosis by Annexin-Ⅴ-fluostaining, electron-microscopy, flow cytometry and immunocytochemical staining of Bcl-2 and Bax. Results: As2O3 and cisplatin had the same cytotoxity on SW1990. The cytotoxic effe ct on tumor cell was produced by induction of apoptosis. Twelve hours after cult ure with 10 μg/ml As2O3, much more SW1990 cells went into apoptosis than t he control. The apoptosis rate reached 24% after 48 h with the similar concentra tion of As2O3. Immunohistochemical study revealed that the expression of Bcl -2 was decreased after treated with As2O3. Conclusion: As 2O3 can depress the proliferation of SW1990 in vitro, mainly through the i nduction of apoptosis, and it is a potential agent for pancreatic cancer chemoth erapy.
5.Effects of high glucose on the expression of angiotensin-converting enzyme/angiotensin converting enzyme 2 in human proximal tubular cells
Hancheng GUO ; Xue MENG ; Tianjun GUAN ; Qing GAO
Chinese Journal of Endocrinology and Metabolism 2011;27(8):680-682
HK-2 cells cultured in vitro were divided into three groups: normal glucose group ( NG ), high glucose group( HG), and mannitol group(MG). The expression of angiotensin-converting enzyme( ACE ) and ACE2 mRNA in HK-2 cells was detected. The concentration of angiotensin Ⅱ ( Ang Ⅱ ) in the culture medium was detected. The mRNA and protein expression of ACE and ACE2 existed in normal cultured HK-2 ( NG group ). In comparison with NG group, the mRNA and protein expressions of ACE in HG group increased significantly ( P<0. 01 ), and the expression of ACE2 mRNA decreased significantly( P<0. 01 ). The level of Ang Ⅱ in HG group was significantly higher than in NG group( P<0. 05 ). The result show that high glucose may induce ACE expression and inhibit ACE2 expression, then promote synthesis of Ang Ⅱ in proximal tubular cells.
6.The research of myocardial fibers character in isolated rats heart based on 7.0 T diffusion tensor ;imaging
Qing FAN ; Yulin GUO ; Yuqing WANG ; Lei WANG ; Fabao GAO
Chinese Journal of Radiology 2016;50(5):384-387
Objective Using 7.0 T diffusion tensor imaging(DTI) to study myocardial fibers character in isolated rats heart in aspect of water molecular diffusion, myocardial mechanics and microstructure. Methods Fixed male rats heart (n=10) underwent DTI and the myocardial structures were quantitatively measured by Diffusion Toolkit and Matlab. The characteristic of myocardial fibers arrangement was observed and FA values and ADC values of myocardial fibers, myocardial fibers density and length, mean helix angle of left ventricular were calculated as well. Mean helix angle of anterior wall, ventricular septum, lateral wall and posterior wall of epicardium and endocardium were compared by using one?way ANOVA. Results The SD rats' myocardial fibers appeared in compact and inerratic distribution from epicardium to endocardium. Compared with HE staining, regular direction and arrangement in fibers were showed in myocardial fibers tracer map and tensor map in papillary muscle plane. Quantitative analysis showed that ADC value of SD rats' myocardial fibers was (9.6 ± 3.6) × 10-4 mm2/s, FA value was 0.80 ± 0.04, myocardial fibers density was (981±24) tracks/mm3 and myocardial fibers length was (6.18±1.71)mm. Mean helix angle of left ventricular epicardium to endocardium ranged from-81.37° to 0° and then gradually change to 82.83° . There were no significant differences in mean helix angle of anterior wall, ventricular septum, lateral wall and posterior wall of epicardium and endocardium, respectively (F=2.25, 0.40, P>0.05). Conclusions This study shows that DTI is an effective method to quantitatively measure the characteristics of myocardial fibers. This study provides useful information for further study of myocardial fibers in heart disease models.
7.Experimental study on arsenic trioxide induced apoptosis of human pancreatic cancer cell line
Yong GAO ; Shaochang JIA ; Jiejun WANG ; Qing XU ; Jing GUO ;
Academic Journal of Second Military Medical University 1982;0(01):-
Objective: To study the effect of arsenic trioxide (As 2O 3) on human pancreatic cancer cell proliferation and apoptosis (mainly early stage) in vitro . Methods: SW1990 cells line were treated with As 2O 3 at different concentration. Cell proliferation was evaluated by MTT and apoptosis by Annexin Ⅴ fluostaining, electron microscopy, flow cytometry and immunocytochemical staining of Bcl 2 and Bax. Results: As 2O 3 and cisplatin had the same cytotoxity on SW1990. The cytotoxic effect on tumor cell was produced by induction of apoptosis. Twelve hours after culture with 10 ?g/ml As 2O 3, much more SW1990 cells went into apoptosis than the control. The apoptosis rate reached 24% after 48 h with the similar concentration of As 2O 3. Immunohistochemical study revealed that the expression of Bcl 2 was decreased after treated with As 2O 3. Conclusion: As 2O 3 can depress the proliferation of SW1990 in vitro , mainly through the induction of apoptosis, and it is a potential agent for pancreatic cancer chemotherapy.
8.Expression of ATP synthase CF1 alpha subunit gene (CTL-spn) as screened by the cDNA-SRAP approach is correlated with spininess in Carthamus tinctorius L.
Dan-dan GUO ; Qing-hua GUO ; Yue GAO ; Mei-li GUO
Acta Pharmaceutica Sinica 2015;50(8):1052-1059
The safflower floret is a traditional Chinese medicine used to promote blood circulation and remove obstruction in the channels. The spines on its bracts are considered a handicap when manual harvest is involved. In this study, cDNA-SRAP was used to systematically investigate which genes are associated with the spines. Sixty pairs of possible primer combinations were used on two cDNA pools representing spininess and spinelessness. Six transcript-derived fragments were identified, of which two with low recombination were sequenced successfully and named as GPY-1 and GPY-2. By using the RACE method, the full-length cDNA of GPY-2 is cloned and named as CTL-spn. The full-length cDNA of CTL-spn was 1 679 bp long with a 1 524 bp ORF encoding a 508 aminoacid protein. The deduced amino acid sequence of the CTL-spn gene shared a high homology (97%) with other known ATP synthase CF1 alpha subunits. Semiquantitative RT-PCR analysis revealed that the mRNA of GPY-1 and GPY-2 accumulated in only spiny lines. Considering the important role of ATP synthase CF1 alpha subunit in plants, it may directly take part in the formation process of spininess and enhancing resistance reaction of spiny safflower. Also, our results provide the important insights for breeding spineless cultivars of safflower.
Adenosine Triphosphate
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Amino Acid Sequence
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Carthamus tinctorius
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enzymology
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genetics
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Chloroplast Proton-Translocating ATPases
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genetics
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DNA Primers
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DNA, Complementary
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Plant Proteins
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genetics
9.Effect of L-carnitine on apoptosis and oxidant damage of cardiomyocytes induced by hypoxia/reoxygenation in vitro
Wenyi GUO ; Yong YANG ; Guoliang JIA ; Rongqing ZHANG ; Qing ZHANG ; Jingxia LI ; Haokao GAO
Chinese Journal of Pathophysiology 1986;0(01):-
AIM: To examine the effects of L-carnitine on apoptosis and oxidant injury in cultured neonatal rat cardiomyocytes induced by hypoxia/reoxygenation and its possible mechanism. METHODS: The cultured cardiomyocytes were divided into three groups, control, A/R group (anoxia for 120 min, reoxygenation for 240 min) and L-carnitine treatment group, in which cells were exposed to 20 mg/L, 50 mg/L, 100 mg/L, 200 mg/L L-carnitine respectively at 2 h before anoxia. The superoxide dismutase (SOD), succinate dehydrogenase (SDH) activities and malondialdehyde (MDA) content were examined, and the apoptosis was determined by flow of cytometry (FCM). In addition, the ultrastructure was observed by transmission electron microscopy. RESULTS: In A/R group, SOD and SDH activities were lower, the apoptosis rate and MDA content were higher than those in control group (P
10.Dyslipidemia and important organ damages in patients with active systemic lupus erythematosus
Huifang GUO ; Chenxing PENG ; Mingfeng ZHANG ; Fuling SHAO ; Lixia GAO ; Qing ZHANG ; Fengzhen LIU
Chinese Journal of Rheumatology 2010;14(1):33-36
Objective To investigate the correlation between dyslipidemia and important organ damage in patients with active systemic lupus erythematosus (SLE) without treatment. Methods Serum sam-ples from 71 active SLE patients and 30 healthy controls were obtained to measure lipid profiles including total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), apolipoproteinA1 (apoA1), apolipoproteinB100 (apoB) and lipoprotein a (LPa). Clinical parameters were recorded. Results The levels of serum TC, TG, LDL, apoB in active SLE patients were higher than those in healthy controls, in contrast,the levels of HDL,apoA1 were much lower (P<0.05 or P<0.01). Patients with important organ damages had longer disease course and elevated levels of serum TC, TG, LDL and apoB concentrations than those without organ damage (P<0.05 or P<0.01), especially in patients with cadiovascular diseases (CVD) (P<0.01). Moreover, these changes in lipid metabolism were positively correl-ated with disease course and negatively with C3 level (P<0.05 or P<0.01). The elevated serum TC and LDL concentrations were negatively correlated with C4 level (P<0.05). Conclusion Severe dyslipidemia is present in active SLE patients.It is correlated with disease course and disease activity. Increased serum TC, TG, LDL and apoB concentrations play key roles in patients with important organ damages.