1.EFFECTS OF MITOGEN-ACTIVATED PROTEIN KINASE ON FREE CALCIUM IN CULTURED HUMAN FIBROBLAST
Biao CHENG ; Xiaobing FU ; Zhiyon SHENG
Medical Journal of Chinese People's Liberation Army 1983;0(05):-
To investigate the effects of basic fibroblast growth factor (bFGF) on intracellular free Ca 2+ of heating injury, and observe the relationship between mitogen activated protein kinases(MAPKs)signal pathways and Ca 2+ mobilization. Cultured human fibroblasts were heated at 45?C for 10min, then divided into four groups :①basic fibroblast growth factor (10ng/ml) treatment; ②preincubated cells with PD98059 (10?mol/L) for 30 min followed by bFGF (10ng/ml); ③preincubated cells with SB203580 (10?mol/L) for 30min followed by bFGF (10ng/ml); ④preincubated cells with PD98059 (10?mol/L) and SB203580 (10?mol/L) for 30min followed by bFGF (10ng/ml). The cells were incubated with fluorescence Ca 2+ dye fluo 3/AM at 37 C for 30min, then measured by using laser scanning confocal microscope. The results showed fluorescent intensity of fibroblast heating injury was weak, the concentration of intracellular free Ca 2+ increased after stimulation with bFGF treatment. PD98059 and SB203580 could induce calcium oscillation. A rapid decrease of fluorescent intensity was observed after cells were preincubated with PD98059 and SB203580 at the same time. bFGF induced an increase of cytoplasmic and intracellular free Ca 2+ concentrations. It is suggested that MAPKs signaling pathway has a feedback regulation for free Ca 2+ mobilization.
2.SIGNAL PATHWAY INVOLVED IN HEAT-STRESSED FIBROBLASTS
Biao CHENG ; Xiaobing FU ; Zhiyong SHENG
Medical Journal of Chinese People's Liberation Army 2001;0(07):-
To explore the activities of signal transduction pathway involved in heat-stressed fibroblast in vitro. Human dermal fibroblasts were cultured in Dulbecco′s modified Eagle′s medium with 5% calf serum at 5%CO 2 in a water-saturated atmosphere. Cultured cells were heated to 45℃ for 10min. Western blotting was used to detect ERK1/2 and JNK expression, and the expression of caspase-3 protein was observed by immunoflurescence technique. The results showed that the MAPKs signal transduction pathway was activated in heat-stressed fibroblasts. The expression of JNK reached the peak at 60min, then maintained up to 180min. The expression of ERKs peaked at 30min, then lowered. The expression of caspase-3 was weak at 30min after heat-stress, and became evidently strong at 60min. The signal pathway of ERKs and JNK played important roles in the changes in biologic characteristics of fibroblasts after heat-stress.
4.Development of gene therapy in wound healing
Biao CHENG ; Xiaobing FU ; Zhiyong SHENG
Chinese Journal of Pathophysiology 2000;0(10):-
The basic concept of gene therapy is to introduce a therapeutic gene into a cell, whose expression can improve to healing of wound. To achieve this goal, the suitable therapeutic gene has been selected and delivered into the reparative cell, which is becoming a focal point works about gene therapy in wound healing. There have been several different therapeutic genes and gene transfer strategies that have been used in models of wound healing. This article discusses several methods that have been used to deliver genes encoding growth factor proteins, stem cells into wounds and the advantages/disadvantages of each approach. We hope a safe vectors system to deliver the effectual transgene in wound healing.
5.Recombinant Human Platelet-derived Growth Factor Enhances Repair of Cutaneous Full-thickness Excision by Increasing the Phosphorylation of Extracellular Signal-regulated Kinase in Diabetic Rat
Biao CHENG ; Hongwen LIU ; Xiaobing FU ; Zhiyong SHENG ; Tongzhu SUN
Chinese Journal of Reparative and Reconstructive Surgery 2006;20(11):1093-1098
Objective To investigate the possible signaling mechanisms by which recombinant human platelet-derived growth factor (rhPDGF) accelerated healing of cutaneous wound in diabetic rats. Methods Four full-thickness skin wounds were incised in the back of 26 male Wistar diabetic rats. The wounded rats were divided into 3 groups (7 or 8 rats each group). One group without treatment was used as a control, and the other 2 groups were treated with rhPDGF at a dose of 7.0 μg/cm2 wound or vehicle ( DMSO/0.9%NaCl, vol/vol 1:1) from 1 to 14 days. The wound healing was evaluated by the measurements of the wound volume and area. Immunofluorescent and immunohistochemical staining were used to examine the phosphorylation of extracellular signal-regulated kinase 1/2(ERK1/2) and the expression of proliferative cell nuclear antigen (PCNA), respectively. Results Granulation tissue appeared in the bed of wound after injury. The number of blood capillary buds and fibroblasts was greater in the rhPDGF-treated group than that in the other 2 groups. A lot of inflammatory cells infiltration and collagen deposition were observed in the wound. The wound-volume in the rhPDGF-treated group was smaller than that in control group ( P < 0.05). The reepithelialization rate in rhPDGF-treated group was higher than that in the other 2 groups at 7 days after injury ( P < 0.05). The expression of PCNA in reparative cells was higher in rhPDGF-treated group than in control group or vehicle-treated group at 3,7 days after injury( P < 0.05). The phosphorylation of ERK1/2 was stronger in rhPDGF-treated group than that in control group or vehicle group at 7 and 14 days after injury( P < 0.05). Conclusion These results suggest that rhPDGF accelerates wound healing and improves healing quality by increasing the phosphorylation of ERK1/2.
6.Role of extracellular signal-regulated kinase 1/2 signal pathway in platelet-derived growth factor promoting the healing of cutaneous full-thickness incisional wounds in diabetic rats
Biao CHENG ; Xiaobing FU ; Zhiyong SHENG ; Tongzhu SUN
Chinese Journal of Trauma 2003;0(08):-
Objective To investigate the possible signal transduction pathway during the course of recombinant human platelet derived growth factor (rhPDGF) promoting cutaneous incisional wound healing in diabetic rats. Methods Four full thickness skin wounds were incised in the back of 26 Wistar rats with diabetes mellitus that were randomly divided into two groups, Group A (diabetic rats control) and Group B (treated with rhPDGF at 7.0 ?g/cm2 wound). The granulation, collagen sedimentation, the reepithelialization rate of rhPDGF as well as the inflammatory cell filtration were observed 3,7 and 14 days after wound. Immunofluorescence staining was used to observe the expression of ERKs either around the wound and in the wound center and immunohistochemical method applied to observe the changes of c-fos, proliferation cell nuclear antigen (PCNA) and focal adhesion kinase (FAK). Results The histological investigation showed a lot of granule tissues in the bed of wound, a large of inflammatory cells infiltration and collagen deposition, active growth of granule tissues and significant wound contraction. The number of blood capillary buds and fibroblasts in the Group B were more than that in the Group A. The immunohistochemistry showed that the expressions of ERK1 and c-fos increased significantly three days, strengthened seven days and went weak 14 days after rhPDGF application. In the Group B, at every time point, the expressions of PCNA and FAK were more significant than those in the Group A. Conclusions ERK1/2 signal pathway exerts function in rhPDGF accelerating wound healing of rats with diabetes mellitus and plays an important role in proliferation and migration of reparative cells.
7.The rate-adaptive response study of integrated sensor pacemakers
Xiaohong PAN ; Ling CHENG ; Cheng-Lin HUANG ; Geng XU ; Guo-Sheng FU ; Jiang SHAN ;
Chinese Journal of Emergency Medicine 2006;0(12):-
Objective To observe the rate-adaptive response of dual sensor pacemakers integrated with activity sensor and minute ventilation sensor.Methods Fifty patients with chronotrepic incompetence were implanted with pacemakers of integrated sensor.The patients with pacemakers implanted were arranged to take upstairs test,downstairs test and tapping test under the monitor of integrated sensor,minute ventilation sensor and activity sensor respectirely.The rate-adaptive responses were tracked down every 15 seconds with remote heart rate monitor.The results were compared with the control group patients with normal sinal chronotropic function(n=15).Results In activity sensor group,pacing rates were significantly higher than the normal control group in downstairs test and tapping test.In minute ventilation sensor group,pacing rates increasement was significantly slower in the beginning of upstairs test.Pacing rates of integrated group were similar to the normal control group in upstairs and downstairs tests.Conclusion The rate-adaptive pacing response of dual sensor integrated with activity sensor and minute ventilation sensor,which is mostly close to the normal chronotropic response,better than that of single sensor.
9.Detection of Salmonella spp.,Escherichia coli and Staphylococcus aureus by Multiplex PCR
Yi-Ping XU ; Wei CHENG ; Yan-Chun SHAO ; Fu-Sheng CHEN ;
Microbiology 1992;0(06):-
According to DNA sequences of the invA gene of Salmonella spp.,the phoA gene of Escherichia coli and the nuc gene of Staphylococcus aureus,three pairs of oligonucleotide primers were designed and synthesized to amplify the special DNA sequences by multiplex PCR. Moreover,the reaction conditions of multiplex PCR were optimized. The results showed the multiplex PCR using the three pairs of primers produced specific amplicons of expected sizes,284bp for Salmonella spp.,622bp for Escherichia coli,484bp for Staphylococcus aureus. The optimized reaction conditions followed as the concentration of primer 40nmol/L for Salmonella spp.,40nmol/L for Escherichia coli,80nmol/L for Staphylococcus aureus,2.4mmol/L Mg 2+ ,200?mol/L dNTP,1.5U Taq DNA polymerase,anneal temperature from 55.0℃ to 57.4℃. Under the condition,the detection limits for DNA template were 10.2pg,10.2pg and 102.0pg for Salmonella spp.,Escherichia coli and Staphylococcus aureus,respectively. The whole process could be completed within 4h. The multiplex PCR assay was a specific,sensitive,rapid and reliable method for detecting Salmonella spp.,Escherichia coli and Staphylococcus aureus,which establish important foundation for simultaneous detection for these three bacteria in food.