Objective To evaluate the effects of the polypeptide growth factors on the periodontal ligament cell(PDLC) based on a comprehensive review onthe literature concerned. Methods The recent literature related to the effects of the polypeptide growth factors on the PDLC were extensivelyand comprehensively reviewed and a corresponding evaluation was made. Results The proliferation and the multidirectional differentiation of thePDLC were found to be the basis for the regeneration of the periodontal tissues. The effects of the polypeptide growth factors on the function of the PDLC became a hot issue of the research on the regeneration of the periodontal tissues. The polypeptide growth factors were found to play an important role in the migration, growth, proliferation, differentiation, and synthesis of protein and matrixof the PDLC. Conclusion The polypeptide growth factors can beused in the periodontal regeneration treatment, but a further research is stillrequired to improve this kind of treatment.
Objective To study the effect of vascular endothelial cell growth factor (VEGF) on repair of bone defect with cortical bone allograft. Methods Forty five New Zealand white rabbits, weighted 2.5-3.0 kg, were made bone defect model of 1.5 cm in length in the bilateral radii and then were randomly divided into 3groups. The defect was repaired with only cortical bone allograft in the control group, with the cortical bone allograft and local injection of human recombinantVEGF in the experimental group, and with the cortical bone allograft and abdominal injection of VEGF PAb3 in the antagonist group. Roentgenography, immunohistochemical staining and tetracycline labelling were carried out to evaluate the reparative results 1, 3, 5, 8 and 16 weeks after operation. Results Immunohistochemical staining results showed that a great deal of blood vessels formed in the experimental group, and the number of blood vessels increased gradually with the time and reached the highest value at the 8th week. Tetracyclinelabelling showed the same result.The best results in callus formation, ossification rate and count of microvascular density were shown in the experimental group, while those in the control group were significantly better than those in the antagonist group (Plt;0.05),but there was no significant difference between the experimental group and the control group at the 8th week and the 16th week (Pgt;0.05). Conclusion VEGF can accelerates the bone formation and angiogenesis in the bone allografts, thus it can promote the repair of bone defects.
Objective To investigate effects of the basic fibroblast growth factor (bFGF) and fibronection (FN) on the osteoblast adhesion on the bio-derived bone. Methods The third generation of the osteoblast was treated with bFGF 0.1, 1, 10, and 100 ng/ml, respectively, and then was seeded in the bioderived bone, which had been modified with FN 0.1, 1, 10, and 100 μg/ml, or Polylysine, respectively. The cell adhesion was measured by the MTT assay. The cell density and the cell appearance were observed by the scanning electron microscope. The abovementioned procedures were repeated by an application of the GRGDS peptide. Results Both FN and bFGF could enhance the osteoblast adhesion efficiency on the bioderived bone (Plt;0.05). However, the osteoblast adhesion efficiency could be significantly strengthened bya combined use of FN and bFGF. FN and bFGF had a significant synergistic effectin statistics (Plt;0.01), but Polylysine and bFGF had no such synergistic effect (P＞0.05). The combined use of FN and bFGF had a better effect on the cell density and the cell appearance than either of them when observed with the scanning electron microscope. Adhesion efficiency generated by the combined use of FN and bFGF was significantly blocked by the application of the GRGDS peptide. Conclusion The combined use of FN and bFGF has a significant synergistic effect on the osteoblast adhesion efficiency on the bioderived bone. This effect is probably mediated by the RGD-integrin α5β1 pathway.
In order to study the effect of vascular endothelial cell growth factor (VEGF) on the survival of skin flap 30 SD rats were used. A randomized flap measuring 7.5 cm x 3.0 cm was created on the back of each SD rat. The treatment group (n = 10) received VEGF 40 ng/flap by subcutaneous injection with microinjector during and 24 hours after operation. The control groups received heparin 16 U/flap (n = 10) or normal saline 800 microliters/flap (n = 10). After operation, on the 3rd and 11th day, the survival rate of the skin flaps and the dermovascular density of each flap were investigated by histological and histo-morphometrical examination. The results showed that there was no significant difference in the survival rate between the treatment group and the controls on the 3rd day after operation, while on the 11th day, there was a significant difference between them, and the survival rate was much higher in the treatment group. Besides, dermovascular density was much more increased in the treatment group than that in the controls, especially in the distal 1/3 of the flap (P lt; 0.02). The conclusion was that VEGF could .
Objective To evaluate the effect of composite (bFGF/PDPB) of basic fibroblast growth factor（bFGF） and partially deproteinized bone (PDPB) on the repair of femoral head defect. Methods Forty-eight femoral heads with defect derived from 24 New Zealand rabbits were divided into 3 groups at random, which were implanted with bFGF/PDPB(group A), PDPB(group B) and nothing(group C) respectively.The rabbits were sacrificed at 2,4,and8 weeks after operation, and then the femoral heads were obtained. The specimens injected with Chinese ink were created. Then X-ray examination, histopathological and morphological examination of blood vessel, and image analysis were made. Results The bone defects healed completely 8 weeks after operation in group A. The implants in the repaired tissue were not substituted completely in group B. The bone defects did not heal completely in group C. Two weeks after operation, affluent newly formed vessels were seen in repaired areas in groupA. No significant difference between group A and group B was observed 8 weeks after operation. In group C, newly formed vessels were scarce 2, 4, and 8 weeks after operation. There were 3 sides rated excellent, 2 good and 1 fair in group A; 1 excellent, 2 good, 2 fair and 1 poor in group B; and 1 fair and 5 poor in group C according to the X-ray evaluation 8 weeks after operation. Eight weeks after operation, the volume fraction of bone trabecula in repaired tissue was higher in group A than that in group B (Plt;0.05), and the fraction in group C was thelowest among the 3 groups (Plt;0.05). Conclusion The composite ofbFGF and PDPB can effectively promote the repair of femoral head defect of rabbit.
【Abstract】Objective To investigate the apoptosis induced by TGF-β1 in human hepatic carcinoma cell lines and its relationship with p53 gene and Smad. Methods Three human hepatic carcinoma cell lines which involving in various status of the p53 gene were used in this study. TGF-β1-induced apoptosis in hepatic carcinoma cell lines was measured by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. To study the mechanism of TGF-β1-induced apoptosis, these cell lines were transfected with a TGF-β1-inducible luciferase reporter plasmid containing Smad 4 binding elements (SBE) and luciferase gene using Lipofectamine 2000, then treated with TGF-β1, relative luciferase activity was assayed. Results Of three cell lines studied with TUNEL assay, TGF-β1 induced apoptosis was observed in HepG2 cells (wild type p53). Huh-7 (mutant p53) and Hep3B (deleted p53) cell lines showed less apoptosis. Luciferase activity assay indicated that the response to TGF-β1 induction in HepG2 cells was increased dramatically but was not significant in Huh-7 and Hep3B cell lines. Conclusion HepG2 cells seem to be highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh7 cell lines. Smad 4 is a central mediator of the TGF-β1 signal transduction pathway.
Objective To observe the influence of the transforming growth factor β1(TGF-β1) on the denervated mouse musclederived stem cells（MDSCs） producing the connective tissue growth factor（CTGF）at different time points in vitro. Methods MDSCs from the primarycultureof the denervated mouse skeletal muscle were isolated and purified by the preplate technique, and they were identified before the culture and after the culturein vitro with TGF-β1 (10 ng/ml) for 24 hours. Then, MDSCs were randomlydivided into 6 groups (Groups A, B, C, D, E and F) according to the different time points, and were cultured in vitro with TGF-β1 (10 ng/ml) for 0, 3, 6, 12, 24 and 48 hours, respectively. The levels of CTGF mRNA in MDSCs were measured by the real time RT-PCR and the expression of CTGF protein was detected by the CTGF Western blot. Results The immunohistochemistry revealed that before the adding of TGF-β1, MDSCs highly expressed Sca-1, with a positivityrate of 96%; however, after the adding of TGF-β1, the positive expression of Sca-1 decreased greatly, with a negativity rate gt;99%. The Western blot test showed that the ratios of CTGF to the average absorbance of βactin in Groups A-F were 0.788±0.123, 1.063±0.143, 2.154±0.153, 2.997±0.136, 3.796±0.153 and 3.802±0.175, respectively. In Groups AD，the absorbance increased gradually, with a significant difference between the abovementioned groups (Plt;0.05). However, in Groups D-F, there was no significant difference between the groups as the promotive tendency became less significant (P＞0.05). The RT-PCR test showed that the △Ct values in GroupsA-F were 1.659±0.215, 1.897±0.134, 2.188±0.259, 2.814±0.263,2.903±0.125 and 3.101±0.186, respectively. In Groups A-D, the increase in the △Ct value was gradual, but the differences were significant between the groups (Plt;0.05). But in Groups E and F, the promotive tendency became less significant（Pgt;0.05）. Conclusion TGF-β1 can promote the production of CTGF inthe mouse MDSCs cultured in vitro and the time-dependent relation exists for 3-12 hours.
PURPOSE:To measure the epidermal growth factor (EGF)contents in vitreous and serum samples in normal subjects and patients with proliferative retinal diseases. METHODS: Using radioreceptor assay(RRA)to measure the EGF contents in vitreous and serum in patients with proliferative diabetic retinopathy (PDR) 16 cases, proliferative vitreoretinopathy (PVR) 20 cases, central retinal vein occlusion (CRVO)16 cases,other retinal vascular diseases 5 cases,and controls 10 cases. RESULTS:The EGF levels in vitreous of the patient group were apparently higher than those of the controls (Plt;0. 001). Among patient group,the EGF contents in vitrectomy fluid was lower than that of original vitreous, reflecting about 60~ 63~ EGF level in original vitreous, Both showed positive correlation. To compare the EGF contents in serum of patients and controls,the EGF contents in serum of PDR group increased significantly. In CRVO group the EGF contents also increased,while in PVR group,the EGF contents were lower than those of the controls. CONCLUSIONS: The increased EGF contents in vitreous of patient group may play a role in the pathogenesis of proliferative retinal diseases. The RRA is a sensitive method for quantitative measurement of growth factor. （Chin J Ocul Fundus Dis,1996,12: 91- 93）
Objective To construct a mammalian expression vector ofbasic fibroblast growth factor (bFGF) and to investigate the expression of bFGFin vitro and in vivo. Methods A mammalian expression vector pcDNA3.1/myc-His(-)C-bFGF was constructed with gene cloning technique. The mammalian expression system was prepared and purified. The expression of bFGF cDNAin cultured transfected cells was examined by RT-PCR and cell immunohistochemistry. The recombinant plasmids, pcDNA3.1/myc-His(-)C-bFGF and pCD2-VEGF121, were transferred into rabbit cervical muscle by direct injection of plasmid following electric pulses in vivo. The transferred gene expression and the biological effect were measured by use of histochemistry and immunohistochemistry analysis. Results The eukaryon expression system pcDNA3.1/myc-His(-)C-bFGF could express the target protein bFGF in vitro. The recombinant plasmids, pcDNA3.1/myc-His(-)C-bFGF and pCD2-VEGF121 were transferred into muscles flap in vivo successfully. The active proteins bFGF and VEGF121were expressed at high levels. Blood vessels increased significantly in the muscles, and blood circulation was improved by local angiogenesis. Conclusion Theeukaryon expression vector of bFGF is constructed and can be expressed successfully in vitro and in vivo. That is a primary preparation for the research on tissue transplantation and tissue engineering with bFGF gene therapy.
ObjectiveTo analyze the regulative rule of mRNA of vascular endothelial growth factor (VEGF) in mice with oxygen-induced retinopathy, and to elucidate the possible mechanism of occurrence of neovascularization in retinopathy of prematurity (ROP).MethodsSixty 7-day-old C57BL/6J mice were divided into oxygen-induced retinopathy group and control group. In oxygen-induced retinopathy group, 36 mice were exposed to 75% oxygen for 5 days and then to room air for 5 days; in control group, 24 mice were raised in room air. Vascular perfusion of fluorescein and retinal stretched preparation were used to observe the morphologic changes of retinal vessels. Reversal transcriptionpolymerase chain reaction (RT-PCR) was used to observe changes of VEGF mRNA in each group. ResultsIn oxygen-induced retinopathy group, the morphologic characteristics of retinal vessels were the unperfused area at the center of superficial and deepseated vessels, and the neovascularization appeared at mid-peripheral retina after 2 days in relative hypoxia condition. The results of RT-PCR showed space-time corresponding relation between expression of VEGF and neovascularization, which meant that the transcription of VEGF mRNA decreased in hyperxia conditionand increased in relative hypoxia condition. ConclusionHypoxia is the main reason of occurrence of retinal neovascularization; increased expression of VEGF caused by relative hypoxia after hyperxia might be effective in reducing the occurrence of neovascularization in ROP.(Chin J Ocul Fundus Dis, 2005,21:292-295)