OBJECTIVE: To observe the effects of hyaluronic acid (HA) and basic fibroblast growth factor (bFGF) on the proliferation of the cells from medial collateral ligament (MCL) and anterior cruciate ligament (ACL) cells. METHODS: The MCL cells and ACL cells of mature New Zealand white rabbit were cultured, while HA, bFGF or HA and bFGF were added to the cell culture media, the cellular proliferation was assayed by MTT method. RESULTS: HA only had no effect on the preoliferation of ACL cells, but had a small stimulatory effect on the proliferation of MCL cells. The addition of 1 ng/ml bFGF enhanced the proliferation of both MCL and ACL cells significantly, and this enhancement was maximal in the concentration of 50 ng/ml. However, the enhancement of proliferation of MCL and ACL cells could be achieved when the combination of HA in concentration of 100 micrograms/ml and bFGF in concentration of 100 ng/ml. CONCLUSION: It is evident that bFGF can enhance the proliferation of the ligament cells. HA can maintain the normal growth of ACL cells with no effect on the proliferation of the cells, while HA has a small stimulatory effect on the proliferation of MCL cells. However, when bFGF is coordinated with HA, more improvement of cellular proliferation can be achieved. HA can be used as a potential carrier for bFGF to enhance the healing of ligamentous tissue injuries.
Objective To investigate the effect and mechanism of growth factors on intestinal compensation after massive intestinal resection， and understand the progress of growth factors in nutrition support treatment for short bowel syndrome （SBS）. Method The related literatures about the application and effect of growth factors in the patients with SBS were reviewed. Results Different kinds of growth factors had different effects on intestinal adaptation after massive intestinal resection. The application of growth factors according to the specific circumstances of the patients with SBS could shorten the residual small intestine compensatory time and improve the nutrition status of the patient with SBS. Conclusions Growth factors play important role in promoting the intestinal adaptation after resection. Different kinds of growth factors have their effects and it’s helpful for getting rid of the total parenteral nutrition early. However， much work still remains to be done.
Objective To investigate the effect of machine-enzyme digestion method on the residual quantity of small intestinal submucosa (SIS) cell and the content of growth factors. Methods Fresh jejunum of pig within 4 hours after harvesting was prepared into SIS after machine digestion (removing placenta percreta, mucosa, and muscular layer), degrease,trypsinization, abstergent processing, and freeze drying. Samples were kept after every preparation step serving as groups A, B, C, D, and E, respectively (n=4 per group). And the fresh jejunum served as control group (group F, n=4). The histological alteration in each preparation process was reviewed with HE staining and scanning electron microscope (SEM). Nest-polymerase chain reaction (PCR) was used to determine the content of death associated protein 12 (DAP12), and enzyme-linked immunosorbent assay (ELISA) was appl ied to detect the content of vascular endothel ial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor β (TGF-β), tumor necrosis factor α (TNF-α). Results HE staining and SEM observation showed that there were residual cells in groups A and B, and there were no residual cells in groups C, D, and E. Nest-PCR test revealed the occurrence of DAP12 in each group. The contents of DAP12 in groups A, B, C, D, E, and F were (18.01 ± 9.53), (11.87 ± 2.35), (0.59 ± 0.27), (0.29 ± 0.05), (0.19 ± 0.04), and (183.50 ± 120.13) copy × 106/cm2. The content of DAP12 in group F was significant higher than that of other groups (P lt; 0.05), groups A and B was higher than groups C, D, and E (P lt; 0.05), there were significantdifferences among groups C, D, and E (P lt; 0.05), and there was no significant difference between groups A and B (P gt; 0.05). The ELISA test showed the content of VEGF, bFGF, TGF-β, and TNF-α in group A was significantly higher than that of groups B, C, D, and E (P lt; 0.05), and there was no significant difference among groups B, C, D, and E (P gt; 0.05). Conclusion SIS prepared by simple mechanical method has more residual cells, while the machine-enzyme digestion method can effectively remove the cells and significantly reduce the DAP12 content. This approach can not obviously reduce the growth factor content in SIS.
Objective To study the effect of transforming growth factor β1(TGF-β1) and insulin-like growth factor 1(IGF-1) during the induction course from marrow mesenchymal stem cells (MSCs) to chondrocytes and to observe the effect of cell density on cell induction. Methods Differential time adherent methods were used to purify MSCs obtained from the bone marrow of Kunming mice. MSCs were cultured under special conditionsto induce themto differentiate into chondrocytes. Toluidine blue staining and immunofluoresence were used to identify those induced chondrocytes.TGF-β1 and IGF-1 were used individually or in combination under two different culture patterns: pellet culture and monolayer culture. According to different growth factors, experiment included 3 experimental groups(TGF-β1+IGF-1 group,10 ng/mland 50 ng/ml respectively;TGF-β1 group, 10 ng/ml; and IGF-1 group, 50 ng/ml) and control group(without growth factor). In TGF-β1+IGF-1 group, toluidine blue staining and immunofluoresence staining were carried out at 14 days and 21 days. The effect ofTGF-β1 and IGF-1 on the expression of collagen Ⅱgene was detected by RT-PCR at 7, 14 and 21 days of induction; the expressionsof collagen Ⅱ were compared between two culture patterns. Results In TGF-β1+IGF-1 group, the histological examination and immunofluoresence showed that those inducted chondyocytes could express collagen Ⅱ at 14 days. The gel electrophoresis results showed that the fragment of collagen Ⅱ gene was seen in TGF-β1+IGF-1 group andTGF-β1 group and that no fragment ofcollagen Ⅱ gene was seen in IGF-1 group and control group. The expression of collagen Ⅱ gene was ber in TGF-β1+ IGF-1 group than inTGF-β1 group, showing significant difference(Plt;0.05). Cells expressed more collagen Ⅱ under pellet culture than under monolayer culture. Conclusion IGF-1 could enhance the effect ofTGF-β1 during the induction course from MSCs to chondrocytes. A certain extent of high cell density is more effective for MSCs to differentiate into chondrocytes.
Objective To review the research progress of growth factor sustained-release microspheres in fat transplantation. Methods The recently published 1iterature at home and abroad related the growth factor sustained-release microspheres in fat transplantation was reviewed and analyzed. Results The sustained-release microsphere carrier materials include natural polymer materials and synthetic polymer materials.The sustained-release complexes of different microsphere materials with different growth factors can promote the vascularization of transplanted fat in a timely manner, improve the survival rate of grafts, and reduce the incidence of complications such as liquefaction, calcification, and necrosis. Conclusion The growth factor sustained-release microspheres have the characteristics of persistence and controllability, which is a research hotspot in the field of fat transplantation and has broad application prospects.
Objective To review the information of platelet gel used in the basic and clinical research in reparative and reconstructive surgery.Methods Literature about platelet gel used on the basic and clinical research was obtained through searching medical data and Internet. The effect of platelet gel on repairing and reconstructing the function and structure of tissue and organ was analyzed. Results Platelet gel had many growth factors and had the ability to improve wound healing and regenesis of bone and other tissues. Conclusion Platelet gel is widely available and almost genuine and is able to improve regenesis of many kinds of tissues. Extensive and intensive research should be made on itsclinical application.
Objective To investigate the mechanism of vascular stromal fraction (SVF) at the early stage after aspirated fat transplantation. Methods Fat was harvested from 5 cases of women undergoing abdominal liposuction operation, and SVF was isolated. Aspirated fat with (group B) or without (group A) SVF was injected subcutaneously into the back of nude mice, and the grafts were harvested at 1, 3, 5, and 7 days. Graft wet weight was measured; and immunohistochemical method (CD31) was performed and the secretion of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were qnantified by Western blot assay. Results The wet weight of transplanted adipose tissue showed an increasing tendency in groups A and B with time, and no significant difference was found between groups A and B (P gt; 0.05). At 1 and 3 days after transplantation, no CD31 positive cells was seen in 2 groups; the CD31 positive cells of group B were significantly more than those of group A at 5 and 7 days (P lt; 0.05), and the CD31 positive cells at 7 days were significantly more than those at 5 days in 2 groups (P lt; 0.05). Western blot test showed that VEGF expression reached peak at 3 days , then decreased gradually; the expression of VEGF protein in group B was significantly higher than that in group A at 1, 3, and 5 days (P lt; 0.05). The expression of HGF protein in groups A and B remained at a high level within 5 days, but it tended to decrease at 7 days, which was significantly higher in group B than that in group A (P lt; 0.05). Conclusion SVF can enhance angiogenesis by secretion of growth factors at the early stage after aspirated fat transplantation.
OBJECTIVE: To investigate protection of biological activity and controlled release of growth factor by means of drug controlled release technique in tissue engineering. METHODS: Using drug controlled release technique that to embed or microcapsulate the biological drug with biodegradable polymer. RESULTS: The aliphatic polylactone could be used as drug carrier for each drug including the biological matter. And the release behavior of the drug could be controlled by adjusting the molecular structure of the carrier and the controlled release method. The successful example, that to realize regeneration of rat’s sciatic nerve with 5, 10, 15 and 20 mm of gap by using polylactide as nerve guide and the embedding growth factor, had been obtained. CONCLUSION: It is possible to realize protection of biological activity and sustained release of growth factor by using aliphatic polylactone as drug carrier.
Objective To study the effect of platelet-rich plasma (PRP) on repairing chronic wounds of lower l imbs. Methods From May 2007 to November 2007, 47 patients suffering from chronic wounds of lower l imbs were treated. There were 41 males and 6 females, aged from 15 to 68 years (43.2 years on average). The disease was caused by tibiofibulafracture in 20 cases, calcaneus fracture in 4 cases, metatarsal fracture in 1 case, multiple open fracture of lower l imbs in 3 cases, tibia osteomyel itis in 10 cases, femur osteomyel itis in 1 case, soft tissue injury of ankle in 4 cases, infection after amputation in 2 cases, infection after foot orthomorphia in 1 case, and infection after calcaneus tendon neoplasty in 1 case. Their chronic wounds did not healed after 2 to 4 months of therapy. Among them, chronic wounds compl icated with fracture nonunion in 23 cases and positive bacterial culture result in 38 cases. Debridement and autogenous PRP gel injection were appl ied every 2 months and for twice. Results The patients were followed up for 4 months after the first PRP injection. Two months after the first PRP injection, chronic wounds contracted significantly in 34 patients with purulence and necrosis tissue cleaned up, circulation of soft tissue improved and exposed bone or muscle tissue covered by neogenetic granulation. No patient was completely cured. Two months after the second PRP injection, the average coverage rate was 79.3% ± 18.0%, the total cure rate was 29.8%. The volume of the chronic wounds decreased by (9.3 ± 4.9) mL after PRP therapy (2.5 ± 2.7) mL when compared with (11.8 ± 5.6) mL of before therapy, showing significant difference (P lt; 0.05). X-ray photograph showed that among the 23 cases of fracture nonunion, fracture healed completely in 9 cases; bony callus formation increased obviously in 12 cases; no significant change was observed in 2 cases. No aggravated sign of osteomyel itis was notified. Positive results of bacterial culture reduced to 15 cases. Conclusion PRP efficiently enhances the recovery of soft tissue defect and speeds up the chronic wounds heal ing oflower l imbs.
Objective To review the recent progress of the researches in the field of cartilage tissue engineering, and to discuss the challenges in construction of tissue engineered cartilage. Methods Literature related with cartilage tissue engineering was reviewed and analyzed. Results Some techniques have been appl ied in cl inical. As far as the seeding cells, induced pluripotent stem cells have attracted much more attention. Current strategies of scaffold designing are trying to imitate both component and structure of natural extracellular matrix. Cartilage regeneration through the autologous cell homing technique el iminate the transplantation of exotic cells and has become the hot topic. Conclusion Successful treatment of the damaged cartilage using tissue engineering method will depend on the advances of stem cell technology development, biomimetic scaffolds fabrication and proper appl ication of growth factors.