BACKGROUND: Many experiments indicate that the angiogenesis of tissue engineered bone graft plays a key role in the osteogenesis.OBJECTIVE: An experimental pattern was set up designed to prepare a kind of vascularized engineered-bone graft for repairing rhesus tibia defects and analyze the relation of angiogenesis and osteogenesis in vivo by rontgenographic and morphological approaches.DESIGN: Random controlled animal experiment.SETTING: Department of Orthopaedics and Traumatology, Nanfang Hospital, Southern Medical University.MATERIALS: The composite graft was constructed by seeding the induced bone marrow stem cells (BMSCs) on to a beta-tricalcium phosphate(3-TCP) scaffold in vitro, a circular cylinder (20 mm × 8 mm diameter) with a slit (width 2 mm and length 3 mm ) open to both ends and slot. Porosity 60% and pore diameter 100-150 μm. Twenty-nine healthy rhesuses aged 4-5 years and weighted 3.5-5 kg were adopted without gender limitation.METHODS: The experiment was conducted in the Department of Orthopaedics and Traumatology, Nanfan Hospital, Southern Medical University from October 2003 to July 2005. ①Bone-periosteum defect of 20 mm was made in the middle part of right tibia of the 27 rhesuses, and randomly divided into 3 groups equally. ②The defect gaps in fascia-blood vessel group (A) were plugged with in vitro engineered composites constructed by bone marrow stem cells and 3-TCP scaffold, which were totally hugged by a sheet of pedicled deep fascia and additionally a corresponding portion of saphenous artery and veins. The gaps in fascia group (B) and control group(C), however, were inserted with fascia-coated tissue engineered bone and tissue engineered bone only, respectively. Furthermore, two rhesuses without filling materials on the defect were picked up as blanks fixed by steel pins. ③The angiogenesis and osteogenesis for each treatment was assessed by radioactive imaging, roentgenographic analyses, blocking density and vaso-area image analysis at time intervals of 4, 8 and 12 weeks postoperative.MAIN OUTCOME MEASURE: The score of radioactive imaging,roentgenographic, morphological and vaso-area image analyses RESULTS: Totally 29 rhesuses were involved in the result analysis.① General observation of samples: In group A, all the surfaces of the implanted material and the central part were wholly wrapped up or replaced by bonelike tissues which were hard and could not be broken. And 2/3 materials had been absorbed; In group B and C, partial materials of the medial surface and the front were not coated or replaced by bonelike tissues, which could be broken with force, and 1/3 material had been absorbed.②Histological observation of scaffolds: With time passing, the scaffold materials were absorbed to different degrees in group A, B and C, among which, group A was most significant; Under the microscope, the implanted materials at 12 weeks were completely coated with the bonelike tissues, while the blood vessels structures in the materials were mostly alveoli alike and multi-braches. In group B, most of the materials at 12 weeks were wrapped up by the new bone, and few blood vessels could be seen in the center of the materials. In group C, the implanted materials at 12 weeks were slightly absorbed. The new bone and the vascular structures were both increased a little, but still very few.③Analyses of vaso-area: The vaso-areas of both central and peripheral parts in group A were significantly bigger than those of group B and C (P ＜ 0.05). Furthermore, it tended to increase with the time.④X-rays observation: At 12 weeks, group A's images presented obviously decreased density which was lower than that of the normal bone in individual areas and the continual bony callus manifested. Whereas group B and C's images showed slightly decreased density and the continual bony callus appeared on the sections. ⑤The roentgenographic scores of bone defects: The results indicates that the scores of group A was better than those of group B and C at 4, 8 and 12 weeks, respectively (P ＜ 0.05).CONCLUSION: ①This study shows that a feasible and effective angiogenesis approach of tissue engineered bone can accelerate osteogenesis in vivo. ②The absorption level is positively related to local angiogenesis.

Objective:To investigate the clinical effect of the anterolateral thigh perforator chimeric flap in the treatment of the wound of diabetic foot ulcer (DFU) .Methods:From January, 2018 to December, 2019, 14 cases wound of DFU of type II diabetic were treated by anterolateral thigh chimeric perforator flap. The patients were 10 males and 4 females, at 49 to 58 years old. Of the 14 patients, 10 with simple peripheral neuropathy, 4 with peripheral neuropathy complicated with vascular disease, and none with single vascular disease. With strict control of patients' blood glucose, antibiotics blended bone cement was applied or filled onto grade 2 or higher grade Wagner's DFU after debridement. In addition, the anterolateral thigh chimeric perforator flap was transferred 2 to 3 weeks later. The size of flap was 8 cm×3 cm-27 cm×7 cm. Regular followed-up were made after surgery.Results:Thirteen flaps survived in one stage after surgery. The other 1 flap had venous vascular crisis, and survived completely after active exploration. The patients were followed-up for 6-12 months. All the flaps survived well in good shape and texture. The donor and recipient areas healed well. The functional recoveries of the DF were satisfactory.Conclusion:Application of anterolateral thigh perforator chimeric flap in repair of the refractory wound of DF achieves a good clinical outcome and effectively improves the life quality of patients.

The differentiation of periodontal ligament (PDL) progenitor cells is important for maintaining the homeostasis of PDL tissue and alveolar bone. Vitamin C (VC), a water-soluble nutrient that cannot be biosynthesized by humans, is vital for mesenchymal stem cells differentiation and plays an important role in bone remodeling. Therefore, the objective of this study was to determine the function and mechanism of VC in PDL progenitor cells osteogenic differentiation at the molecular level. We demonstrated that VC could induce the osteogenic differentiation and maturation of PDL progenitor cell without other osteogenic agents. During the process, VC preferentially activated ERK1/2 but did not affect JNK or p38. Co-treatment with ERK inhibitor effectively decreased the Vitamin C-induced expression of Runx2. ERK inhibitor also abrogated Vitamin C-induced the minimized nodules formation. PELP1, a nuclear receptor co-regulator, was up-regulated under VC treatment. PELP1 knockdown inhibited ERK phosphorylation. The overexpression of PELP1 had a positive relationship with Runx2 expression. Taken together, we could make a conclude that VC induces the osteogenic differentiation of PDL progenitor cells via PELP1-ERK axis. Our finding implies that VC may have a potential in the regeneration medicine and application to periodontitis treatment.
Ascorbic Acid ; pharmacology ; Butadienes ; pharmacology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Co-Repressor Proteins ; antagonists & inhibitors ; genetics ; metabolism ; Core Binding Factor Alpha 1 Subunit ; genetics ; metabolism ; Humans ; MAP Kinase Signaling System ; drug effects ; Mitogen-Activated Protein Kinase 1 ; antagonists & inhibitors ; metabolism ; Mitogen-Activated Protein Kinase 3 ; antagonists & inhibitors ; metabolism ; Nitriles ; pharmacology ; Periodontal Ligament ; cytology ; Phosphorylation ; drug effects ; RNA Interference ; RNA, Small Interfering ; metabolism ; Stem Cells ; cytology ; Transcription Factors ; antagonists & inhibitors ; genetics ; metabolism ; Up-Regulation ; drug effects

Objective: To investigate the feasibility and effectiveness of the superficial temporal artery frontal branch flap combine with the retrograde retroauricular artery flap in repairing the preauricular defects. Methods: The superficial temporal artery frontal branch flap with hair is designed for sideburns reconstruction, and the hairless retrograde retroauricular artery flap for repair the hairless area which is between the tragus and the temples. The donor sites were closed directly. Results: From September 2012 to September 2015, 9 cases were treated. All flaps survived completely. Surgical incisions and wounds at donor sites and recipient sites healed primarily. All cases were followed up for 6-18 months (10 months on average) and cosmetic results were satisfactory without visible scar. Conclusions The method of the superficial temporal artery frontal branch flap combined with the retrograde retroauricular artery flap for the repair of preauricular a large skin defect is simple with less and inconspicious auxiliary incision. The sidebums and hairless area can be simultaneously reconstructed with satisfactory appearance.