In this experiment ,the sciatic nerves or twen-ty-eight rats were cut and then anastomosed withbiological adhesive agent or by suture in randonand the latter as control. The biological adhesive a-gent from human plasma was composed of fibrino-gen coagulase and medullary sheath of the nervetaken at the anasomosis region were studied histol-gically. The results of the experimental group wsasignificantly superior to the control.
To find new technique for repair of peripheral nerve defect, the nerve elongation repair technique was adopted. Two cases with nerve defect were treated by this method. One was a 12 year old male, the defect length of right radial nerve was 7.2 cm at the elbow. The other one was a 28 year old male, the defect length of left ulnar nerve the was 5 cm at elbow. In this method, the nerve was elongated by slow stretch from distal and proximal end of the ruptured nerve. After a few days, the nerve was repaired by direct suture. After operation, the function of nerves were recovered in 119 days and 114 days respectively. Follow-up for 5 years, the function of the effected limbs were recovered to the normal side. It was concluded that: (1) the peripheral never can be elongated by slow stretch; (2) to stretch the nerve end in a rubber tube can prevent adhesion and connective tissue blocking; (3) strength and supporting point of stretching should be designed carefully.
The biomaterial, chitin, was used to create a nerve regeneration chamber for bridging healing experiment of sciatic nerve of rats having a defect of 12mm. The crude Schwann cells were introduced into the chambers in one group and the other group had no crude Schwann cells in the chamber and the results of the two groups were compared with those having the nerve defects bridged with skeletal muscles. The specimens were observed by macroscopic, microdissection. electrophysiologic testing, HRP retrograde labelling, histologic and electron microscopic examinations at 4, 8, and 12 weeks after the operation. The results showed that atthe 8th week, the regenerating nerve fibers from the cephalad ends had united with the fibers of the caudal ends of the divided nerves either the crude Schwanneclls were introduced or not, but the morphology of the regenerating nerve, the way of regeneration and the recovery of the function of the extremities were far superior in the group that no cruds Schwann cells had been introduced than those with crude Schwann cell introduced and those bridged by skeletal muscles.
Objective To study the outcomes of nerve defect repair with the tissue engineered nerve, which is composed of the complex of SCs, 30% ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeable poly (D, L-lacitic acid) (PDLLA) catheters. Methods SCs were cultured and purified from the sciatic nerves of 1-day-old neonatal SD rats. The 1st passage cells were compounded with bFGF-PLGA sustained release microspheres andECM gel, and then were injected into permeable PDLLA catheters with PLGA microfilaments inside. In this way, the tissueengineered nerve was constructed. Sixty SD rats were included. The model of 15-mm sciatic nerve defects was made, and then the rats were randomly divided into 5 groups, with 12 rats in each. In group A, autograft was adopted. In group B, the blank PDLLA catheters with PBS inside were used. In group C, PDLLA catheters, with PLGA microfilaments and 30% ECM gel inside, were used. In group D, PDLLA catheters, with PLGA microfilaments, SCs and 30% ECM gel inside, were used. In group E, the tissue engineered nerve was appl ied. After the operation, observation was made for general conditions of the rats. The sciatic function index (SFI) analysis was performed at 12, 16, 20 and 24 weeks after the operation, respectively. Eelectrophysiological detection and histological observation were performed at 12 and 24 weeks after the operation, respectively. Results All rats survived to the end of the experiment. At 12 and 16 weeks after the operation, group E was significantly different from group B in SFI (P lt; 0.05). At 20 and 24 weeks after the operation, group E was significantly different from groups B and C in SFI (P lt; 0.05). At 12 weeks after the operation, electrophysiological detection showed nerve conduct velocity (NCV) of group E was bigger than that of groups B and C (P lt; 0.05), and compound ampl itude (AMP) as well as action potential area (AREA） of group E were bigger than those of groups B, C and D (P lt; 0.05). At 24 weeks after the operation, NCV, AMP and AREA of group E were bigger than those of groups B and C (Plt; 0.05). At 12 weeks after the operation, histological observation showed the area of regenerated nerves and the number of myel inated fibers in group E were significantly differents from those in groups A, B and C (Plt; 0.05). The density and diameter of myel inated fibers in group E were smaller than those in group A (Plt; 0.05), but bigger than those in groups B, C and D (P lt; 0.05). At 24 weeks after the operation, the area of regenerative nerves in group E is bigger than those in group B (P lt; 0.05); the number of myel inated fibers in group E was significantly different from those in groups A, B, C (P lt; 0.05); and the density and diameter of myel inated fibers in group E were bigger than those in groups B and C (Plt; 0.05). Conclusion The tissue engineered nerve with the complex of SCs, ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeables PDLLA catheters promote nerve regeneration and has similar effect to autograft in repair of nerve defects.
Objective To analyze the diagnostic value of shear wave elastography (SWE) combined with vascular endothelial growth factor B (VEGF-B) and hemoglobin A1c (HbA1c) in early diabetic peripheral neuropathy (DPN). Methods A total of 100 patients with type 2 diabetes mellitus (T2DM) admitted to Mianyang Central Hospital between October 2020 and October 2023 were selected and divided into a T2DM with DPN group (n=31) and a T2DM without DPN group (n=69) based on the presence or absence of DPN. Additionally, 50 healthy individuals from the same hospital’s health examination center were included as a healthy control group. The basic clinical characteristics, mean elasticity (Emean) values of the left and right median and tibial nerves, serum VEGF-B, and HbA1c levels were compared among the three groups. The diagnostic efficacy of SWE, VEGF-B, and HbA1c for DPN was evaluated using receiver operating characteristic (ROC) curves, and Pearson correlation analysis was performed to assess the relationships between median/tibial nerve Emean and VEGF-B/HbA1c. Results The Emean values of the left and right median nerves, Emean values of the left and right tibial nerves, serum VEGF-B, and HbA1c levels in the T2DM with DPN group were significantly higher than those in the T2DM without DPN group and the healthy control group (P<0.05). The Emean values of the left and right median and tibial nerves, Emean values of the left and right tibial nerves, and HbA1c level in the T2DM without DPN group were significantly higher than those in the healthy control group (P<0.05), while no significant difference was observed in serum VEGF-B level between the T2DM without DPN group and the healthy control group (P>0.05). The area under the ROC curve for the combined diagnosis of DPN using SWE, VEGF-B, and HbA1c was 0.859 [95% confidence interval (0.828, 0.955)]. The sensitivity of the combined diagnosis (93.72%) was significantly higher than that of individual diagnoses (78.82%, 75.39%, and 71.05%, respectively; P<0.05), while the specificity (88.64%) showed no significant difference compared to individual diagnoses (80.18%, 78.96%, and 82.88%, respectively; P>0.05). Positive correlations were observed between median/tibial nerve Emean and VEGF-B/HbA1c levels (r=0.428, 0.395, 0.416, and 0.416, respectively; P<0.05). Conclusions Elevated median/tibial nerve Emean, serum VEGF-B, and HbA1c levels are closely associated with DPN. The combination of SWE, VEGF-B, and HbA1c improves diagnostic sensitivity for DPN, demonstrating significant clinical value.
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...
OBJECTIVE: To study the effects of Schwann cell cytoplasmic derived neurotrophic proteins (SDNF) on the regeneration of peripheral nerve in vivo. METHODS: Ninety adult SD rats were chosen as the experimental model of degenerated muscle graft with vascular implantation bridging the 10 mm length of right sciatic nerve. They were divided randomly into three groups, 30 SD rats in each groups. 25 microliters of 26 ku SDNF (50 micrograms/ml, group A), 58 ku SDNF (50 micrograms/ml, group B) and normal saline(group C) were injected respectively into the proximal, middle and distal part of the degenerated muscle grafts at operation, 7 and 14 days postoperatively. The motorial function recovery assessment was carried out every 15 days with the sciatic nerve function index(SFI) after 15 days to 6 months of operation. Histological and electrophysiological examination of regenerating nerve were made at 1, 3 and 6 months postoperatively. RESULTS: There were significant statistic differences between the both of experimental groups(group A and B) and control group(group C) in the respects of the histological, electrophysiological examination and SFI(P lt; 0.01). CONCLUSION: The 26 ku SDNF and 58 ku SNDF can improve the regeneration of the injured peripheral nerve in vivo.
OBJECTIVE: To investigate the effect of olfactory ensheathing cells (OECs) on functional recovery after sciatic nerve injury. METHODS: Upon silicone-tubulization of transected sciatic nerve in 30 adult rats. Thirty rats were divided into two groups(SAL group and OECs group); saline and OECs were injected into the silicone chamber in SAL group and in OECs group respectively. The status of functional recovery of injured sciatic nerve was observed by electrophysiological analysis, axon morphometry analysis. RESULTS: In OECs group on the 30th and the 90th days after sciatic nerve transection: 1. The latent period of CMAP shortened by 0.60 ms and 0.56 ms; the nerve conduction velocity promoted by 6.42 m/s and 5.36 m/s; the amplitude enhanced by 3.92 mv and 5.84 mv, respectively; 2. The HRP positive cells in lateral nucleus of spinal anterior horn increased by 11.63% and 25.01%; 3. The number of nerve fibers increased by 1,047/mm2 and 1,422/mm2 and the thickness of myelim sheath increased by 0.43 micron and 0.63 micron, respectively. CONCLUSION: The olfactory ensheathing cells are capable of promoting the functional recovery after peripheral nerve injury.
Objective To investigate the promotion effect of neurotropic reinnervation with chemically extracted acellular nerve allograft. Methods The sciatic nerves of 5 healthy adult SD rats, regardless of gender and weighing 270-300 g, were collected to prepare chemically extracted acellular nerve allograft. Eighteen healthy adult Wistar rats, regardless of genderand weighing 300-320 g, were made the model of left sciatic nerve defect (10 mm) and randomly divided into 2 groups: autograft (control group, n=9) and allograft group (experimental group, n=9). The defects were bridged by acellular nerve allograft in experimental group and by autograft by turning over the proximal and distal ends of the nerve in control group. At 3 months after transplantation, dorsal root ganglion (DRG) resection operation was performed in 6 rats of 2 groups. At 3 weeks after operation, the sural nerves were harvested to calculate the misdirection rate of nerve fibers with pathological staining and compute-assisted image analysis. Cholinesterase staining and carbonic anhydrase staining were performed in the sural nerve of 3 rats that did not undergo DRG resection at 3 months. Results The results of chol inesterase staining and carbonic anhydrase staining showed that experimental group had less brown granules and more black granules than control group. After DRG resection, count of myelinated nerve fiber were 4 257 ± 285 in the experimental group and 4 494 ± 310 in the control group significant (P lt; 0.05). The misdirection rate was 2.27% ± 0.28% and 7.65% ± 0.68% in the experimental group and in the control group respectively, showing significant difference (P lt; 0.05). Conclusion Chemically extracted acellular nerve allograft can not only act as a scaffold in the period of nerve defects repair, but markedly enhance the effects of neurotropic reinnervation.
ObjectiveTo investigate the correlation between serum level of 25(OH)D3 and peripheral neuropathy in patients with impaired glucose tolerance. MethodsA total of 108 patients with impaired glucose tolerance treated or examined between January 2012 and July 2014 were recruited in this study. According to whether peripheral neuropathy was combined, the patients were divided into neuropathy group (n=50) and non-neuropathy group (n=58). The level of 25(OH)D3 was measured and compared between the two groups, and the correlation of 25(OH)D3 with the clinical indexes of impaired glucose tolerance was analyzed. ResultsThe level of 25(OH)D3 in the neuropathy group and non-neuropathy group was respectively (16.1±4.2) and (19.6±4.7) ng/mL with a significant difference (P<0.05). The 25(OH)D3 deficiency rate of the above two groups was respectively 80.0% and 41.38%, also with a significant difference (P<0.05). The 25(OH)D3 level had a negative correlation with body mass index (BMI) and glycosylated hemoglobin (P<0.05). Conclusions There is a significant relationship between impaired glucose tolerance and 25(OH)D3 level. The 25(OH)D3 level has a negative correlation with BMI and glycosylated hemoglobin.