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.
Objective To evaluate the bone regenerative potential of reconbinant human bone morphogenetic protein 2(rhBMP-2) / collagen on adult rat calvarial bone. Methods A tight subperiosteal pocket was produced under both sides ofthe temporal muscle in rats. rhBMP-2 / collagen was implanted in one side and collagen alone was implanted in the other side as control. The rats were sacrificed 2, 4 and 8 weeks after operation. The specimen was harvested and examined histologically. For morphometric analysis, the thickness of the temporal bone of both sides was measured and compared. Results The rhBMP-2 / collagen onlay implant resulted in active bone formation and the augmented bone was connected directly with the original bone, whereas the collagen alone resulted in neither bone nor cartilage production. The ossification process in the rhBMP-2 / collagen occurred directly through bone formation, similar to intramembranous ossification. Conclusion rhBMP-2 / collagen is an effective material as a biological onlay implant.
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 observe the clinical manifestations, therapeutic efficacy and results of bacterial culture of seven patients of scleral buckle (SB) infection after scleral bulking surgery. Methods Seven patients (seven eyes) underwent SB removal for SB infections were enrolled in this study. The patients included four males (four eyes) and three females (three eyes). The patients aged from 12 to 69 years, with a mean age of 42.7 years. There were four right eyes and three left eyes. The duration (interval between primary surgery and SB removal) ranged from two weeks to ten years, with a mean of 47.5 months. Six patients were concurrent with systemic disease. All the patients were examined for visual acuity, slit lamp microscope and indirect ophthalmoscope examination. Some patients also received external eye examination and fundus photography. Whether SB exposure or not and the clinical manifestations were observed. SB removal was performed in all the patients and the SB were sent to the laboratory for bacterial culture. The follow-up time ranged from two weeks to eight months, with a mean of 3.2 months. Whether infections recurrence and retinal detachment or not were observed. Results SB exposure was in three eyes. Obvious ocular pain and swelling, conjunctival hyperemia and visible yellow-white discharge in the conjunctival sac were presented in two eyes; irritation and discharge were in one eye. No SB exposure was in four eyes. Ocular pain and swelling, conjunctival hyperemia and visible yellow-white discharge in the conjunctival sac were presented in two eyes. Repeated subconjunctival hemorrhage and diplopia were presented in one eye. Visual acuity decline, conjunctival sac discharge and total retinal detachment were in one eye. All patients had no intraocular inflammation. The infection was controlled after SB removal and the retina was attached during the follow-up. The bacterial culture were all positive, which included Staphylococcus aureus, Staphylcoccus epidermidis and Erysipelothrix rhusiopathiae, Gram positive corynebacterium, Aspergillus flavus, Kocuria roseus, Streptococcus oralis, Maxwell Corynebacterium. Conclusions The clinical manifestations of SB infection and the pathogenic microorganisms are variable. SB removal can control the infection.
Along with the wide application of silicone gel implants in augmentation mammaplasty, more complications appeared. The author reported 24 cases of complicationssince 1989, including one case of heamtoma, one case of infection, two cases of injury of the sensory nerves to the nipple, four cases of asymmetric breast (as ymmetry in position and size), three cases of deformed appearance, six cases of constracture of the fibrous coating membrane, one case of rupture of prosthesis,one case of sinus formation and three cases of abnormal milk secretion. The causes of the complications and their prevention were discussed.
Objective To systematically review the effectiveness and safety of autologous implantation of stem cells for diabetic peripheral neuropathy (DPN). Methods Randomized controlled trials on relevant studies were retrieved in databases including CBM (1978-2011.6), CNKI (1979-2011.6), MEDLINE (1950-2011.6), PubMed (1950-2011.6), EMbase (1970-2011.6) and The Cochrane Library (Issue 3, 2011). References of the included studies were also retrieved. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data, and assess the methodological quality of the included studies. Then, meta-analysis was performed using RevMan 5.0 software.Results Four RCTs involving 68 patients (136 limbs) were included, most of which were low in methodological quality. The results of meta-analysis indicated that, autologous stem cell therapy improved or even eliminated DPN symptoms including pain, numbness, and cold sensation in the limbs, intermittent limping, and rest pain. Compared with the routine therapy, autologous stem cell therapy improved tibial sensory nerve conduction velocity (MD=5.75, 95%CI 3.86 to 7.64, Plt;0.000 01), tibial motor nerve conduction velocity (MD=4.04, 95%CI 0.90 to 7.18, P=0.001), sural sensory nerve conduction velocity (MD=7.47, 95%CI 4.00 to 10.94, Plt;0.000 1), and sural motor nerve conduction velocity (MD=3.38, 95%CI 0.07 to 7.58, P=0.05), with no adverse reaction reported. Conclusion Current evidence shows that, autologous stem cell therapy is effective in treating DPN. Due to the lack of high quality studies, more high quality RCTs are needed to verify the above conclusion.
Objective To study the effect of motor nerve implantation after ectopic transplantation of skeletal muscle on nerve regeneration in rat. Methods Sixty Sprague-Dewley male 8 monthold rats were randomly divided into 3 groups: control group,in situ implantation group and ectopic transplantation group. In control group, obturator nerve controlling right gracilis was cut off. In in situ implantation group, the right gracilis was cut off and replanted to its original site, and the obturator nerve was implanted to the muscle. In ectopic transplantation group, the right gracilis was cut off and transplanted to the muscle of the left leg, and the obturator nerve was implanted to the muscle. After 25 weeks, the neurophysiological information was collected through electromyography and the weight of the muscle was measured. Results The potentialwithout control of the nerve existed in control group. There were no significant differences in latency, amplitude and conduct velocity betweenin situ implantation group and ectopic transplantation group(Pgt;0.05).The atrophy of gracilis was dominant incontrol group, the weight of the muscle was 158.0±19.3 mg. The weights of the muscle were 509.6±14.5 mg in ectopic transplantation group and 516.8±12.7 mg in in situ mplantation group, showing no significant difference (P＞0.05). The weights of the muscle in in situ implantation and ectopic transplantation group were larger than that in control group, showing significant difference(P＜0.05). Conclusion Motor nerve implantation after ectopic transplantation of skeletal muscle could prevent the atrophy of the muscle and resume partial function of nerve.
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 investigate the survival effect and reaction mechanismsof motor neurons after reimplantation of the avulsed root into the spinal cord,and to observe the survival and differentiation in the spinal cord after brachial plexus roots avulsion. Methods Thirty adult Wistar rats were randomly devided into the control group and the experimental group (n=15). Laminectomy of C4-6 was performed via a posterior approach. The ventral and dorsal roots of C5，6 were both avulsed from the spinal cord outside the dura mater and within the vertebral canal.For the experimental group, the ventral root of C6 wasreimplanted into the ventralhorn under microscope. The dorsal root was left. The ventral and dorsal roots of C5 were placed inside the nearby muscles. For the control group, the ventral and dorsal roots of both C5 and C6 were placed inside the nearby muscles. At 2, 4, 6, 8, 12 weeks postoperatively, the C6 spinal cord was stained with HE. The changes of the number and morphology of motor neurons were observed onHEstained sections. The C6 spinal nerve root was stained with silver nitrate, andthe regeneration of nerve fiber was observed. Results All rats were recovered well and their wounds were healed at primary stage. The gross observation showed that the avulsed nerve roots in control group adhered to adjacent muscles, however the one in experimental groups which had been implanted into spinal cord adhered to scar tissues and were not separated from spinal cord. At each time point postoperatively, the HEstained transverse sections showed that the number of motor neurons decreased significantly with soma swollen and atrophied, Nissle bodies decreased or disappeared. The survival rates of motor neurons in the control group were 60.9％±5.8%,42.3％±3.5％,30.6％±6.1％27.5％±7.9％ and 20.4％±6.8％ respectively；in the experimental group,the survival rates were 67.1％±7.4％,56.3％±4.6％,48.7％±8.8％,44.2％±5.5％ and 42.5％±8.3％ respectively. The survival rates of motor neurons in the experimental group was higher than those in the control group at all time points,showing statistically significant difference（Plt;0.01）.At 12 weeks postoperatively, thesilver nitrate stained specimen from the C6 nerve root showed regeneration of the motor neurons in the ventral horn into the reimplanted nerve root through axon in the experimental group,but the degeneration of the nerve fiber appeared and the number of the myelinated nerve fiber decreased in the control group. Conclusion Through reimplantationof the avulsed ventral nerve root into the ventral horn, degeneration of the motor neurons in the ventral horn can be reduced. After reimplantation of avulsed nerve root, there is axonal regrowth of motor neurons into the spinal nerve root and regeneration of the myelinated nerve fiber also appears.