An experimental study of small-caliber tissue engineering vessels with acellular matrix / 中华整形外科杂志

<p><b>OBJECTIVE</b>To observe the mechanical properties of the prefabricated connective tissue tube as blood vessel substitute and its changes after implantation at the femoral artery.</p><p><b>METHODS</b>The acellular matrix tube of 8-12 cm in length with a silicone rod inside it was implanted into dog peritoneal cavity. 3 weeks later, a new formed tube around the silicone rod was transferred to the femoral artery as blood vessel substitute. The mechanical properties and histological examination of the blood vessel substitute were assessed and compared to those of the carotid artery and vein. 6 months after transfer, the patency of the blood vessels substitute was observed. The histological change was studied by light microscopy, scanning and transmitting electron microscopy.</p><p><b>RESULTS</b>(1) The mechanical properties of blood vessel substitute was not as strong as artery, but better than the vein. (2) There were elastic and collagen fibers with many fibroblasts around the tube wall, but few mesothelial cells around the inner wall. All of the blood vessel substitutes (n = 6) were found to keep patency and the structure of the blood vessels substitutes became similar to femoral artery 6 months after they had been grafted to the femoral artery.</p><p><b>CONCLUSIONS</b>These results suggest that tissue engineering in vivo is a good approach to construct vessels substitute. The tissue tubes made in dog's peritoneal cavity have good condition when it is used as a blood vessel substitutes.</p>

Decellularized aorta of fetal pigs as a potential scaffold for small diameter tissue engineered vascular graft / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>For cardiovascular tissue engineering, acellularized biomaterials from pig have been widely investigated. Our purpose was to study mechanical properties and biocompatibility of decellularized aorta of fetal pigs (DAFP) to determine its potential as scaffold for small diameter tissue engineered vascular graft.</p><p><b>METHODS</b>Descending aorta of fetal pigs was removed cells using trypsin, ribonuclease and desoxyribonuclease. Mechanical properties of DAFP were evaluated by tensile stress-strain and burst pressure analysis. Assessment of cell adhesion and compatibility was conducted by seeding porcine aortic endothelial cells. To evaluate biocompatibility in vivo, DAFP was implanted subcutaneously into adult male Sprague Dawley rats for 2, 4 and 8 weeks.</p><p><b>RESULTS</b>Histochemistry and scanning electron microscopy examination of DAFP revealed well-preserved extracellular matrix proteins and porous three-dimensional structures. Compared with fresh aorta, DAFP had similar ultimate tensile strength, axial compliance and burst pressure. Cell culture studies in vitro showed that porcine aortic endothelial cells adhered and proliferated on the surfaces of DAFP with excellent cell viability. Subdermal implantation demonstrated that the DAFP did not show almost any immunological reaction and exhibited minimal calcification during the whole follow-up period.</p><p><b>CONCLUSION</b>The DAFP has the potential to serve as scaffolds for small diameter tissue engineered vascular graft.</p>

Biocompatibility of decellularized canine carotid artery allograft cross-linked by carbodiimide / 中华整形外科杂志

<p><b>UNLABELLED</b>OBJECTIVE Crosslink decellularized canine carotid artery allograft by EDC [1-3-(dimethylamino)propyl-3-ethylcarbodiimide methiodide] and evaluate the biocompatibility of it.</p><p><b>METHODS</b>Use the multi-step detergent-enzyme method to construct decellularized canine carotid artery allograft and cross-link it by EDC with the weight ratio of decellularized artery to EDC 1:1 and 1:2. Evaluate the biocompatibility of it by the cytotoxical MTT test and the rat subdermal bury test.</p><p><b>RESULTS</b>Decellularized canine carotid artery cross-linked by EDC has a lower degradation rate treated by collagenase type II, the result of MTT test show that the EDC cross-linked decellularized artery has no cytotoxity and the rat subdermal bury test show that crosslinking greatly enhance the ability of decellularize artery to resist the enzyme degradation and lower the immune reaction. The more the artery was cross-linked , the more effects it has.</p><p><b>CONCLUSIONS</b>Decellularized canine carotid artery cross-linked by EDC has fairly good biocompatibility and ability to resist the collagenase degradation.</p>

Vascular anatomy and clinical applications of the distally based superficial sural artery island flap / 中华整形外科杂志

<p><b>OBJECTIVE</b>To document the vascular anatomy of the distally based superficial sural artery flap and to study the vascular anastomoses between the superficial sural artery and the septocutaneous perforators of the peroneal artery.</p><p><b>METHODS</b>Ten fresh human cadavers were injected with lead oxide, gelatin and water. Twenty lags were then dissected and an overall map of the cutaneous vasculature was constructed. Vascular communications between the superficial sural artery and the lowest septocutaneous perforator of the peroneal artery was evaluated to determine the cutaneous vascular territory of the superficial sural flap. The distally based superficial sural artery island flap was used in 26 cases.</p><p><b>RESULTS</b>There is constant vascular anastomosis between the superficial sural artery and the lowest septocutaneous perforator of the peroneal artery. The 26 flaps survived uneventfully except for two of partial fat necrosis.</p><p><b>CONCLUSION</b>The anatomic information enhances our understanding of flap design.</p>

Microvascular free muscle flap reconstruction of soft-tissue defects with bone exposure after the distal tibial fracture / 中华创伤骨科杂志

Objective To present a method to treat soft tissue defects with bone exposure after the distal tihial fracture.Methods Twenty-six patients who had suffered from the distal tibial fracture complications leading to exposure of the bone or fixation material sought medical help in our department.The internal fixation material was removed and radical revision of dead and infected tissue was carried out in all cases.Five of the 26 cases were treated using a free microvascular muscle flap and the mesh skin graft by one stage.Twenty-one of them were re- paired with the same method by two-stage.Results Follow-ups were 10 to 24 months.The microvascular re- construction was successful in 22 patients.Two of the 26 cases had partial necroses of the skin graft,and the other two cases had delayed wound healing.All the fractures united.Conclusion Microvascular free muscle flap re- construction of the leg is regarded as a reliable method to treat legs with massive soft-tissue defects or defects with bone exposure and chronic infection or fistulation at the distal leg.

The neurovascular anatomy and its clinical implication of the rectus femoris muscle / 中华整形外科杂志

<p><b>OBJECTIVE</b>The objective of this anatomic study was to investigate the intramuscular neurovascular configuration and to evaluate whether the muscle could be split into two functional units in transplantation.</p><p><b>METHODS</b>Ten fresh cadavers and ten preserved cadavers were used in the study. A mixture of lead oxide, gelatin and water was injected to the femoral artery of the fresh cadaver. The rectus femoris muscle with its neurovascular pedicles was dissected and radiographed.</p><p><b>RESULTS</b>Three vascular patterns of the rectus femoris muscle were found in the 40 cadaver legs. The muscle received its blood supply through a single vascular pedicle (12.5%), or a dominant pedicle with 1-2 ramified (80%), or two dominant vascular pedicles (7.5%).</p><p><b>CONCLUSIONS</b>The study provided a detailed description on the intramuscular neurovascular territories of the rectus femoris muscle. Based on the neurovascular supply of the muscle, it is possible to subdivide the muscle into two functional units for segmental muscle transfer.</p>

Transferring neurovascular rectus femoris muscle segment for treatment of facial paralysis / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate a new technique for functional treatment of chronic facial paralysis.</p><p><b>METHODS</b>Based on anatomy of intramuscular neurovascular structure in the rectus femoris muscle, 7 consecutive patients with facial paralysis were treated by using a technique of microsurgically free-transferring neurovascular rectus femoris muscle segment to the face in one-stage. Follow-ups were 10 to 24 months.</p><p><b>RESULTS</b>All of the 7 patients showed significantly improvement in the appearance of the oral commissure and oral competence. No complications occurred in the donor site.</p><p><b>CONCLUSIONS</b>The above mentioned technique may have the advantages of preventing the intramuscular nerve and vessel from the surgical injury during splitting the muscle. It could also maintain the transferred muscular segment in a proper tension in the recipient site.</p>