Objective To explore the feasibility of allogeneic marrow stromal stem cells(MSCs) as seed cells to construct tissue engineered bone bydetecting the expressions of interleukin 2(IL-2) and IL-2 receptor in rhesus monkeys after implanting these tissue engineered bones.Methods Engineered bones were constructed with osteoblasts which derived from allogeneic MSCs and bio-derived materials in vitro, and then were implanted to bridge 2.5 cm segmental bone defects of left radius in 15 rhesus monkeys as experimental group, bioderived materials only were implanted to bridge same size defects of right radius as control group. Every 3 monkeys were sacrificed in the 1st, the 2nd, the 3rd, the 6th andthe 12th weeks postoperatively and the expressions of IL-2 and IL-2 receptor in blood and graft samples were detected quantitatively by enzymelinked immuneosorbent assay (ELISA).Results There was no significant difference in the contents of IL-2 and its receptor between 2 groups（P＞0.05）. The contents ofIL-2 and its receptor increased from the 2nd week and maintained high level from the 2nd to the 6th week, but decreased after 6 weeks.ConclusionTissue engineered bones constructed with allogeneic MSCs and bio-derived materials show low immunogenicity. Allogeneic MSCs may be used as seed cells to construct tissue engineered bone.
To evaluate the effect of technique combination of implant-retented titanium lattice with decalcified dental matrix (DDM) implanting. Methods Six healthy male dogs (weighing of 10-20 kg) were randomly divided into 3 groups. All the premolars were extracted on both sides of the jaw in dogs. After 2 weeks, titanium lattice and implant were implanted in the maxillary premolar region with DDM on one side (experimental group), but without on the other side (control group) of each dog. After 4, 9 and 14 weeks, respectively, 2 animals were individually killed each time, and the samples wereevaluated by general observation, X-ray examination, histological observation and histomorphometric analyses. Results General observation: Among the 6 dogs, there was no postoperative infection or death. The X-ray examination showed that the bone density of the experimental group was greater than the control group at 4 and 9 weeks, and had no significant difference as to the vicinity bone at 14 weeks. On the other hand, the density of the control group was very low under the titanium lattice and around the implant. The experimental group revealed a ridge augment of (1.93 ± 0.24) mm, and control group (-1.02 ± 1.20) mm (P lt; 0.05). Developed bone sponge could be found after 14 weeks. Histological observation showed that in the experimental group, the DDM surface was nearly absorbed at 4 weeks. A few new bones were formed at 9 weeks. The whole DDM was absorbed; the trabecular bone was thick and arranged regularly; and the intergradations of implant were observed at 14 weeks. In the control group, there were some inflammatory fibers around the neck of implant at 4 weeks. The inflammatory condition extended to the root of implant and the titanium lattice at 9 weeks. There was no newly-formed bone under the titanium lattice at 14 weeks. Histomorphometric analyses showed that the implant contact bone ratio approached 1 ∶ 1, and showed no significant difference between the new bone fragment and former bone fragment in the experimental group. Conclusion This augmentation of alveolar ridge evaluated by the study is appl icable, but further study is necessary.
Objective To assess the sensory restoration after the greater auricular nerve is implanted into the flap to repair the buccal defect in rabbits. Methods Fifteen Japanese white rabbits, weighing 2.0-2.5 kg, were randomly divided into the experimental group (nerve implanted), the control group (nerve unimplanted), and the normal group (without any treatment). In the experimental and the control group, circular defects (2.0 cm×2.0 cm) were constructed in the left cheek of the rabbits. Then, the cervicalflaps (4.5 cm×2.5 cm) were transferred and the great auricular nerve was implanted into the defects in the experimental group, and the flaps without any nervewere implanted into the defects in the control group. The subjects in the normal group were given no treatment. After 6 months, the nerve discharge, the HE staining, and the immunohistochemical method were used to assess the regeneration of the nerve fibers. Results The nerve discharge and the percentage of the different kinds of the nerve fibers in the experimental group (124.2±33.8 roots) were not statistically different from those in the normal group （138.4±20.4 roots，Pgt;0.05）, but significantly different from those in the control group（18.8±5.6 roots,Plt;0.05）. In the center of the flap in the experimental group, the receptive field of the nerve fibers was identical to theimplanting approach of the greater auricular nerve. The HE staining and the immunohistochemical staining showed that the density of the regenerated fibers in the center of the flap in the experimental group reached the normal level.There was no regenerated fibers in the control group. Conclusion The great auricular nerve implanted into the cervical flaps has a good effect on reconstruction of the buccal defect in rabbits.
Objective To observe the changes of electrophysio logical results in rabbits with normal and injured photoreceptor due to subretinal implantation of chip. Methods Photoreceptor damage was induced by injection with NaIO3 solution in 22 out of 30 rabbits. A chip with the diameter of 3 mm made by the array composed of 90 microelectrodes photodiode and conjoint electrode was implanted into subretinal space or choroid of the right eyes of 22 rabbits with photoreceptor and 4 normal rabbits, and the left eyes were the control. The examinations of local flash-visual evoked potential (F-VEP), local flash-electroretinogram (F-ERG), full-field F-ERG and full-filed F-VEP were measured respectively.Another 4 rabbits underwent biocular extirpation for path ological examination . Results In 22 rabbits with photo-receptor damage, the amplitude of the main wave of local ERG was obviously higher in 11 eyes with chips than that in the control ones, and was also higher in 2 eyes with chips of the 4 mormal rabbits than that in the control eyes. No wave was found in an eye with retinal hole on the surface of the chip. The repeataility of main amplitude of local-VEP and full-field F-VEP is not satisfactory; no significant changes were observed between chip-implanted eyes and the control eyes examined by full-filed F-ERG. Conclusion The implanted chip may stimulate local retina and induce electrical activities after stimulated by light. (Chin J Ocul Fundus DIs, 2006, 22: 324-327)
OBJECTIVE: To sum up the experimental development and clinical application of prefabricated flap. METHODS: The reported experimental results and clinical application of prefabricated flap extensively reviewed. RESULTS: Previous studies had proved that the revascularization of prefabricated flap mainly through anastomoses of implanted vessels and the original vessels of the flap, the implanted vessels slowly formed a new and complete blood vessel network, which could dominate the whole flap, three to four weeks later, the new vessels were mature and the flap could be transferred. Clinically, the superficial temporal vessels, gastroepiploic vessels, circumflex femoral vessels and thoracodorsalis vessels could be harvested for prefabricated flap with satisfactory results. CONCLUSION: Prefabricated flap provides a new method for the treatment of complicated defects.
Abstract In order to have more selective sources of skin flaps to repair soft tissue defects, the prefabricated flap combining with skin expander was tried. Implanted the dorsal thoracic artery and vein with a muscle bundle of latissimus dorsi into the lateral thoracic wall subdermally andset a skin expander subcutaneously. Injected saline into the expander to inflate the flap gradually. In a month, an axial flap with the dorsal thoracic vesselswas prepared. the flap was transferred to the defect by vascular anastomosis technique. This method was applied in two cases, one to the left ankle, another to the left side of the neck. The sizes of the two flaps were 20cm×14cmand 22cm×15cm respectively. After operation, the flaps were alive completely. The advantages included selective source of vascular pedicle, thinpliable flap with enough blood supply, and direct closure of the donor site without skin graft.
ObjectiveTo evaluate the safety of TiRobot-guided percutaneous transpedicular screw implantation.MethodsThe medical records of 158 patients with thoracolumbar fractures and lumbar degenerative diseases who underwent percutaneous transpedicular screw implantation were retrospectively analyzed between January 2018 and December 2020. The patients were divided into trial group (TiRobot-guided screw implantation, 86 cases) and control group (fluoroscopy-guided screw implantation, 72 cases). There was no significant difference in gender, age, pathology, lesion segment, and the average number of screw implantation per case (P>0.05). The operation time, fluoroscopic dose, fluoroscopic time, and fluoroscopic frequency were compared between the two groups. One day postoperatively, the convergence angle was measured and the penetration of the pedicle cortex was evaluated according to Gertzbein-Robbins classification standard.ResultsThe operation time, fluoroscopic dose, fluoroscopic time, and fluoroscopic frequency of the trial group were significantly lesser than those of control group (P<0.05).One day postoperatively, the convergence angle of trial group was (21.10±4.08)°, which was significantly larger than control group (19.17±3.48)° (t=6.810, P=0.000). According to the Gertzbein-Robbins classification standard, 446 pedicle screws were implanted in trial group, trajectories were grade A in 377 screws, grade B in 46 screws, grade C in 23 screws, and the accuracy of screw implantation was 94.8%; 380 pedicle screws were implanted in control group, trajectories were grade A in 283 screws, grade B in 45 screws, grade C in 44 screws, grade D in 6 screws, grade E in 2 screws, and the accuracy of screw implantation was 86.3%. There was significant difference in the accuracy of screw implantation between the two groups (χ2=25.950, P=0.000). ConclusionCompared with traditional percutaneous transpedicular screw implantation, TiRobot-guided percutaneous transpedicular screw implantation can improve the accuracy of screw implantation, reduce radiation exposure, and improve surgical safety, which has a good application prospect.
OBJECTIVE To investigate the feasibility of prefabricating a specified shape autograft capable of transfer using coral and type I collagen as a carrier for recombinant human bone morphogenetic protein-2 (rhBMP-2). METHODS In this study, the composite of rhBMP-2, coral and type I collagen was made certain shape to prefabricate vascularized osteomuscular autograft capable of microvascular free tissue transfer and autogenous bone graft with certain shape and titanium implant in it. The composite was implanted in the iliac area in dog with the titanium implant at the same time. After 3 months and 4 and a half months of implantation, the composites were studied with gross measurement, X-ray, and histological examinations. RESULTS After 3 months, composited bone was turned to bone tissue, and the shape of iliac bone was changed with implant in it, bone interface was seen between new bone and implant. And new bone was matured after 4 and a half months. CONCLUSION Coral and type I collagen are effective carrier for rhBMP-2 to prefabricate vascular osteomuscular autograft with certain shape. The use of rhBMP-2 for tissue engineered microvascular free bone flaps has an unlimited potential and adds a new dimension to maxillofacial reconstruction.
Abstract： Objective To investigate the early and mid-term outcomes of morphologic tricuspid valve replacement by means of intravalvular implantation in corrected transposition of great arteries（cTGA）. Methods From January 2009 to January 2012，11 patients with cTGA were surgically treated in Fu Wai Hospital. There were 9 male patients and 2 female patients with their mean of age of（37.8±11.7）years and mean body weight of（73.0±11.3）kg. All the patients underwent morphologic tricuspid valve replacement with preservation of the entire valvular and subvalvular apparatus. Simultaneous surgical procedures included repair of ventricular septal defect in 2 patients，repair of atrial septal defect in 4 patients，pulmonary valvuloplasty in 1 patient，reconstruction of functional right ventricular outflow tract in 4 patients and repair of coronary-pulmonary artery fistula in 1 patient. Postoperative New York Heart Association （NYHA） classification, cardiothoracic ratio, morphological right ventricle ejection fraction, end-diastolic dimension of morphological right ventricle and left atrium were evaluated during follow-up. Results All the 11 patients were successfully surgically treated and followed up for an average duration of（13.0±10.6）months. There was no statistical difference between postoperative and preoperative average cardiothoracic ratio （0.54±0.06 vs. 0.57±0.09，t=1.581，P＞0.05），morphologic right ventricle ejection fraction （52.8%±9.0% vs. 54.9%±9.5%, t =0.712，P＞0.05），and end-diastolic dimension of . morphological right ventricle （54.3±7.5 mm vs. 56.9±9.2 mm，t =0.988，P＞0.05）. There was statistical difference between postoperative and preoperative average end-diastolic dimension of left atrium（42.1±8.9 mm vs. 53.4±11.1 mm，t =3.286，P＜0.05）and NYHA classification（Z = -2.640，P＜0.05）. Conclusion Intravalvular implantation of morphologic tricuspid prosthesis can protect the physiological structure of morphologic right ventricular and prevent furtherdamage to its function caused by morphologic tricuspid valve insufficiency. Postoperative dimension of morphologic left atrium and cardiac function are significantly improved. The early and mid-term outcomes are satisfactory．
To study the recovery method and effect of amputated foot after temporary ectopic implantation. Methods Two male patients with amputated foot were treated with temporary ectopic implantation in July 2001 and January 2002. Amputated foot was caused by mechanical injury and crush injury. After 6 hours, temporary ectopic implantation of amputated foot was given and replantation was done 3 months after primary operation. The recovery methods were as follows: automatic and passive motion, high pressure oxygen, massage, protective and positional feel ing training, etc. The effects of recovery was observed. Results All amputated foots survived after operation, the time of follow-up was 6 years,and 5 years and 7 months. Extension degree of first metatarsal digital joint was 12º and 15º, flex degree of first metatarsal digital joint was 15º and 13º, and extension degree of other metatarsal digital joints was 8º and 9º. Force degree of extension muscle was 4, force degree of flex muscle was 4, and two-point discrimination was 20 mm and 18 mm. Patients recovered their superficial sensibil ity, touch sense, deep pain sense and topognosis. The skin color and temperature were normal. And the patients could do some housework. Conclusion Temporary ectopic implantation of amputated foot can recover the function of amputated foot by motor and sensitive recovery methods.