Schwanns cells were obtained from the distal end of the sciatic nerve following Wallerian degeneration of SD rats. These cells were cultured with the anteriorhorn neuron of spinal cord of 14dayold SD rat fetus. The two kinds of cells were separated by a slice. Through the microscope, the dendrites and the morphology changes at the 24th, 48th, 72th, and 96 th hour after culture were observed. It was demonstrated that the Schwanns cells played the role of maintaining the survival of neuron and promoting the growth of dendrites. It was said that the Schwanns cells could secrete neurotrophic factor which made the body enlarged and caused the dendrites enlonged to several times of the body.
OBJECTIVE: To review the role of thyroid hormone in the peripheral nerve regeneration. METHODS: The recent literatures of experimental study and clinical application on the role of thyroid hormone in nerve regeneration were reviewed. The researches on expression, isoform and changes of thyroid hormones in rat sciatic nerve in normal or injury were summarized. The effect of thyroid hormone on local rat sciatic nerve was studied, too. RESULTS: Nuclear thyroid hormone receptors expressed in numerous nuclei of sciatic nerve during a limited period of development extending from the third week of embryonic life to the end of the second postnatal week and after injury of adult sciatic nerve. A single and local administration of thyroid hormone at the level of the transected sciatic nerve produced a lasting effect on peripheral nerve regeneration. CONCLUSION: The beneficial effects of thyroid hormones upon injured peripheral nerve may have considerable therapeutic potential.
The model of the denervated lateral head of gastrocnemius musde was adopted in this experiment on 50 rabbits. At random, the denervated muscle on oneside received the soleus muscle bundles with neurovascular pediele implantation (MBNPI). While the other side received the direct soleus nerve implantation (DNI). Eighteen weeks later after the two types of implantations the electromyography, force of muscles, histochmical findings and the electronic microscopic examination of the dernervated muscles of the two...
Objective To observe the efficiency and biological characteristics in regenerating in vitro tissue-engineered cartilage from epiphyseal chondrocyte-scaffold complex. MethodsThe first passage epiphyseal chondrocytes were collected and mixed with the biological gel-matrix, the chondrocyte-gel fluid wasdropped into the scaffold to form a complex. The complexes were in vitro cultivated. The changes of complexes in morphology and synthesis of collagens type ⅡandtypeⅠ and aggrecan were observed under the gross and the inverted and light microscopes. The sulfate GAG content in complexes was measured by the the modified dimethylmethylene blue method. Results During cultivation, thecomplexes could keep its original shape with the stable homogeneous three-dimensional distribution of chondrocytes，gradually became milk white and translucence with their rigidity increasing. In the 1st week, the chondrocytic lacunae formed in the complexes. After 2 weeks, the complex was gradually reorganized into the mature engineered cartilage with rich collagen typeⅡand aggrecan and typical cartilage histological structure, but with negative immunological staining of collagen typeⅠ. In the 4th week, the engineered cartilage resembled the nature epiphyseal plate in the characteristic of histological structure, and had over 34% of the sulfate GAG content of the natural epiphyseal plate. Conclusion Theepiphyseal chondrocyte-scaffold complex can be reorganized into typical cartilage with the epiphyseallike histological structure, and be fit for repairing the epiphyseal defect. The tissue engineered cartilage cultivated for 1-2 weeks may be a good choice for repairing epiphyseal defect.
Basing on the experimental results, 48 nerve defects (with the length of 3-4 cm in 21 cases, 4.1-5cm in 25 cases and 6cm in 2 cases) were repaired clinically by using vaseularized nerve sheath canal with living Schwann s cells, 87.5 percent of them obtained good results. The advantages were: (1) The neural sheath had rich blood supply with resultant less scar from its healing; (2) The living Schwann s cells would secrete somatomedin to promote the reproduction of neural tissues; and (3) The useless neurofib...
Schwanns cell (SC) was isolated from sciatic nerve of adult rat with Wallerine degeneration. After culture, SC-serum free culture media (SCSFCM) was obtained. By ultrafiltration with PM-10 Amicon Membrane, electrophoresis with DiscPAGE,and electrical wash-out with Biotrap apparatus, D-band protein was isolated from the SC-SFCM. The D-band protein in the concentration of 25ng/ml could affect the survival of the spinal anterior horn neuron in vitro, prominently and itsactivity was not changed after being frozen. The molecular weight of the protein ranged from 43 to 67 Kd. The D-band protein might be a neurotrophic substancedifferent from the known SCderived neurotrophic factors (NTF). Its concentration with biological activity was high enough to be detected. The advantages of MTT in assessment of NTF activity were also discussed.
Objective To study an effect of the peripheral nerve allograft with subcutaneous preservation at different times on the sciatic nerve regenerationin rats. Methods Fifty-five Wistar rats were used in this experiment, which were randomly divided into the following 5 groups: the experimental groups (Groups A, B, C, 10 rats), the control group (Group D, 10 rats), and the donorgroup (Group E, 15 rats). In the experimental groups, a 15-mm segment of the sciatic nerve harvested from the donors was separately inserted into the subcutaneous compartment on the left thigh after the 1week (Group A), 2-week (Group B), and 3week (Group C) preservation; the segment of the sciatic nerve in the subcutaneous compartment was removed and transplanted into a 10-mm defect of theright sciatic nerve, which was made immediately. In Group D, a 10-mm sciatic nerve defect was made and immediately repaired in situ on the right thigh. The function of the sciatic nerve was evaluated by the sciatic functional index (SFI) at 2, 4, 6, 8, 10 and 12 weeks after operation. The histological and electrophysiological examinations were performed at 12 weeks after operation. Results After operation, SFI decreased gradually at 12 weeks afteroperation, SFI inGroups A and D was at the minimal level and had a significant difference compared with that in Groups B and C (Plt;0.05).There was no significant difference between Group A and Group D. A large number of the myelinated nerve fibers and a small number of the unmyelinated nerve fibers were regenerated in Groups A and D. The number and the structure of the regenerated nerve were similar to the normal ones. The number and the size of the regenerated axon had a significant difference compared with those in Groups B and C (Plt;0.05). There was no significant difference between Group A and Group D. The conduction velocity and the latent period of the motor nerve had significant differences between Groups A and D and Groups B and C (Plt;0.05), and there was no significant difference betweenGroupA and Group D. Conclusion The nerve allograft with a 1-weeksubcutaneous preservation can promote nerve regeneration better.
Abstract In order to investigate the mechanism ofregeneration of lymphatic vessel, the regulatory control of various cell factors on the new born bovine lymphatic endothelial cell (NBLEC) was observed. The cell factors used for investigation were bFGF, TGFα, EGF, TNFα and IL-1α. The results showed that bFGF, TGFα and EGF could stimulate NBLEC proliferation and DNA synthesis in dosage-dependent pattern. Combined use of either two factorsdid not increase the effect, and bFGF could increase cell migration and improve the activity of tissue plasminogen activator (t-PA). TNFα and IL-α inhibited NBLEC regeneration and DNA synthesis but TNFα improved the activity of t-PA. It could be concluded that growth factor and inflammatory factor had differentrole on regeneration of NBLEC, such as cell proliferation, migration and t-PA activity. bFGF was the main factor which improved the regenerationof lymphatic endothelial cell.
OBJECTIVE: To validate the hemostatic properties of collagen sponge made in China. METHODS: The experimental model of superficial cut of liver was established in 20 Sprague-Dawley adult rats, which were divided into two groups randomly. Collagen sponge or gelatin sponge was used to cover the cut respectively. Hemostatic result was observed. Afterwards, standard liver trauma model by resection left front liver lobe was made, wound was treated with collagen sponge or gelatin sponge respectively. Hemostatic result was observed. Concurrent hemostatic time and bleeding amount were noted. At 7, 14 and 20 days after operation, intra-abdominal adhension, infection and healing state of liver were observed by exploratory laparotomy. The histological changes of regenerate liver tissue were observed by microscopy. RESULTS: Collagen sponge adhered to wound well. Concurrent hemostatic time and bleeding amount in collagen sponge group were superior to those of gelatin sponge (P lt; 0.05). The histological examination showed that collagen sponge was absorbed and degraded rapidly, regenerative hepatocytes could be induced. CONCLUSION: Collagen sponge has fine hemostatic properties and can induce regeneration of hepatocytes effectively. It is worth popularizing for its convenience in clinical application and its properties of rapid degradation and absorption.
In order to observe the role of genetically modified Schwann cell (SC) with pSVP0Mcat in the regeneration of injured spinal cord, the cells were implanted into the spinal cord. Ninety SD rats were used to establish a model of hemi-transection of spinal cord at the level of T8, and were divided into three groups, randomly, that is, pSVP0Mcat modified SC implantation (Group A), SC implantation (Group B) and without cell implantation as control (Group C). After three months the presence of axonal regeneration of the injured spinal cord was examined by means of horseradish peroxidase (HRP) retrograde labelling technique and stereography. The results indicated that HRP labelled cells in Group A and B could be found in the superior region of injured spinal cord and the brain stem such as the red nuclei and oculomotor nuclei. The density of ventral hom neurons of the spinal cord and the number of myelinated axons in 100 microns of the white matter was A gt; B gt; C group. In brief, the pSVP0Mcat modified SC intraspinal implantation could promote regeneration of the injured spinal cord.