Objective To comment on the recent advances of production and application of the bio-derived scaffold in the tissue engineered peripheral nerve. Methods The recent articles were systematically analyzed, and then the production methods of the bio-derived scaffold and its application to the tissue engineered peripheral nerve were evaluated and prospected. Results B iological tissues were processed by some methods to produce the bio-derived materials. These mat erials could maintain the structure and components of the tissues. Moreover, the immunogenicity of these materials was reduced. Conclusion Application of the bio-derived materials is a trend in the fabricating scaffold of the tissue en gineered peripheral nerve.
Objective To explore the histochemical staining for distinguishing and local izing nerve fibers and fascicles at histological level in three-dimensional reconstruction of peri pheral nerves. Methods The right median nerve was harvested from one fresh cadaver and embedded in OCT compound. The sample was serially horizontally sl iced with 6 μm thickness. All sections were stained with Karnovsky-Roots method (group A, n=30) firstly and then stained with toluidine blue (group B, =28) and Ponceau 2R (group C, n=21) in proper sequence. The results of each step were taken photos (× 100). After successfully stitching, the two-dimensional panorama images were compared, including texture feature, the number and aver gray level of area showing acetylchol inesterase (AchE) activity, and result of auto microscopic medical image segmentation. Results In groups A, B, and C, the number of AchE-positive area was (21.63 ± 4.06)× 102, (20.64 ± 3.51)× 102, and (20.54 ± 5.71)× 102, respectively, showing no significant difference among 3 groups (F=0.64, P=0.54); the mean gray level was (1.41 ± 0.06)× 102, (1.10 ± 0.05)× 102, and (1.14 ± 0.07)× 102, respectively, showing significant differences between group A and groups B and C (P lt; 0.001). In the image of group A, only AchE-positive area was stained; in the image of group B, myelin sheath was obscure; and in the image of group C, axons and myelin sheath could be indentified, the character of nerve fibers could be distinguished clearly and accurately, and the image segmentation of fascicles could be achieved easier than other 2 images. Conclusion The image of Karnovsky-Roots-toluidine blue-Ponceau 2R staining has no effect on the AchE-positive area in the image of Karnovsky-Roots staining and shows better texture feature. This improved histochemical process may provide ideal image for the three-dimensional reconstruction of peri pheral nerves.
【Abstract】 Objective To report cl inical experience in the use of temporary intravascular shunts (TIVS) for quickrestoration of perfusion to the extremity with major vascular injury. Methods Between August 2009 and March 2011, TIVSwas applied temporarily to restore blood perfusion to the extremity in 6 patients with major extremity vascular structure injury secondary to trauma (4 patients) or tumor resection (2 patients), who would received vascular transplantation and underwent long ischemia. The patterns of vascular shunts included external carotid artery-subclavian artery, axillary artery-axillary artery, axillary vein-subclavian vein, brachial artery-brachial artery, brachial vein-brachial vein, brachial artery-radial artery, femoral artery-popliteal artery, and popliteal artery-posterior tibial artery. After TIVS, extensive debridement, fracture fixation, or tumor excision was performed. Then the shunted tubes were removed, and the vessels were repaired definitly. Six vessels were repaired by transplanting the great saphenous veins; one vessel was anastomosed directly without tension; and one vessel was repaired by artificial vascular graft. Results All shunted tubes were successfully established within 5 to 10 minutes (mean, 8.2 minutes). The duration of bypass ranged from 67 to 210 minutes. After establishment of TIVS, blood perfusion to the affected limb was improved. When shunted tubes were removed, thrombosis and partial obstruction occurred in one who accepted amputation, and the others kept patency. No loosening of tubes and haemorrhage occurred. At 2-15 months of follow-up, affected limbs had good blood supply. Conclusion TIVS is rapid and simple, which can quickly restore blood perfusion to the extremity with major vascular injury and shorten the ischemic time of the affected extremity.