ObjectiveTo review the related studies on the application of nanomaterials in the treatment of osteomyelitis, and to provide new ideas for the research and clinical treatment of osteomyelitis.MethodsThe literature about the treatment of osteomyelitis with nanomaterials at home and abroad in recent years was reviewed and analyzed.ResultsAt present, surgical treatment and antibiotic application are the main treatment options for osteomyelitis. But there are many defects such as antibiotic resistance, residual bone defect, and low effective concentration of local drugs. The application of nanomaterials can make up for the above defects. In recent years, nanomaterials play an important role in the treatment of osteomyelitis by filling bone defects, establishing local drug delivery system, and self-antibacterial properties.ConclusionIt will provide a new idea and an important research direction for the treatment of osteomyelitis to fully study the related characteristics of nanomaterials and select beneficial materials to make drug delivery system or substitute drugs.
ObjectiveTo summarize the regulatory role of long non-coding RNA (lncRNA) in peripheral nerve injury (PNI) and neural regeneration.MethodsThe characteristics and mechanisms of lncRNA were summarized and its regulatory role in PNI and neural regeneration were elaborated by referring to relevant domestic and foreign literature in recent years.ResultsNeuropathic pain and denervated muscle atrophy are common complications of PNI, affecting patients’ quality of life. Numerous lncRNAs are upregulated after PNI, which promote the progress of neuropathic pain by regulating nerve excitability and neuroinflammation. Several lncRNAs are found to promote the progress of denervated muscle atrophy. Importantly, peripheral nerve regeneration occurs after PNI. LncRNAs promote peripheral nerve regeneration through promoting neuronal axonal outgrowth and the proliferation and migration of Schwann cells.ConclusionAt present, the research on lncRNA regulating PNI and neural regeneration is still in its infancy. The specific mechanism remains to be further explored. How to achieve clinical translation of experimental results is also a major challenge for future research.
Objective To investigate the feasibility of selenium-methylselenocysteine (SMC) to promote peripheral nerve regeneration and its mechanism of action. Methods Rat Schwann cells RSC96 cells were randomly divided into 5 groups, which were group A (without any treatment, control group), group B (adding 100 μmol/L H2O2), group C (adding 100 μmol/L H2O2+100 μmol/L SMC), group D (adding 100 μmol/L H2O2+200 μmol/L SMC), group E (adding 100 μmol/L H2O2+400 μmol/L SMC); the effect of SMC on cell proliferation was detected by MTT method, and the level of oxidative stress was detected by immunofluorescence for free radicals [reactive oxygen species (ROS)] after determining the appropriate dose group. Thirty-six 4-week-old male Sprague Dawley rats were randomly divided into 3 groups, namely, the sham operation group (Sham group), the sciatic nerve injury group (PNI group), and the SMC treatment group (SMC group), with 12 rats in each group; the rats in the PNI group were fed with food and water normally after modelling operation, and the rats in the SMC group were added 0.75 mg/kg SMC to the drinking water every day. At 4 weeks after operation, the sciatic nerves of rats in each group were sampled for neuroelectrophysiological detection of highest potential of compound muscle action potential (CMAP). The levels of inflammatory factors [interleukin 17 (IL-17), IL-6, IL-10 and oxidative stress factors catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA)] were detected by ELISA assay. The luxol fast blue (LFB) staining was used to observe the myelin density, fluorescence intensity of glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) was observed by immunofluorescence staining, and myelin morphology was observed by transmission electron microscopy with measurement of axon diameter. Western blot was used to detect the protein expressions of p38 mitogen-activated protein kinases (p38MAPK), phosphorylated p38MAPK (p-p38MAPK), heme oxygenase 1 (HO-1), and nuclear factor erythroid 2-related factor 2 (Nrf2). ResultsMTT assay showed that the addition of SMC significantly promoted the proliferation of RSC96 cells, and the low concentration could achieve an effective effect, so the treatment method of group C was selected for the subsequent experiments; ROS immunofluorescence test showed that group B showed a significant increase in the intensity of ROS fluorescence compared with that of group A, and group C showed a significant decrease in the intensity of ROS fluorescence compared with that of group B (P<0.05). Neuroelectrophysiological tests showed that the highest potential of CMAP in SMC group was significantly higher than that in PNI and Sham groups (P<0.05). ELISA assay showed that the levels of IL-6, IL-17, and MDA in PNI group were significantly higher than those in Sham group, and the levels of IL-10, SOD, and CAT were significantly lower; the levels of IL-6, IL-17, and MDA in SMC group were significantly lower than those in PNI group, and the levels of IL-10, SOD, and CAT were significantly higher (P<0.05). LFB staining and transmission electron microscopy showed that the myelin density and the diameter of axons in the SMC group were significantly higher than those of the PNI group and the Sham group (P<0.05). Immunofluorescence staining showed that the fluorescence intensity of GFAP and MBP in the SMC group were significantly stronger than those in the PNI group and Sham group (P<0.05). Western blot showed that the relative expressions of Nrf2 and HO-1 proteins in the SMC group were significantly higher than those in the PNI group and Sham group, and the ratio of p-p38MAPK/p38MAPK proteins was significantly higher in the PNI group than that in the SMC group and Sham group (P<0.05). Conclusion SMC may inhibit oxidative stress and inflammation after nerve injury by up-regulating the Nrf2/HO-1 pathway, and then inhibit the phosphorylation of p38MAPK pathway to promote the proliferation of Schwann cells, which ultimately promotes the formation of myelin sheaths and accelerates the regeneration of peripheral nerves.
Objective To study the microstructural change of detrusor muscle and neuromuscular junction (NMJ) after bladder functional reconstruction for atonic bladder caused by medullary cone injury and to discuss the feasibility of bladder functional reconstruction for improving the detrusor muscle degeneration. Methods A total of 104 adult female Sprague-Dawley rats (weighing, 200-250 g) were randomized divided into 3 groups: normal group (n=8), control group (n=48), and experimental group (n=48). No treatment was given in normal group; the medullary cone injury was established by sharp transection of spinal cord at L4, 5 levels in control group; and the anastomosis of bilateral L5 ventral root (VR)-S2 VR and L5 dorsal root (DR)-S2 DR was performed for bladder functional reconstruction after modeling of medullary cone injury in experimental group. After operation, the survival condition of rats was observed. At 3 days and 3 consecutive days before 1, 2, 3, 4, 5, and 6 months after operation, the residual urine volume was measured; at 1, 2, 3, 4, 5, and 6 months after operation, the detrusor muscle was harvested to measure the muscle fiber cross-sectional area by HE staining, to calculate the percentage of connective tissue by Masson trichrome staining, and to observe the ultrastructure of the detrusor muscle and the NMJ by transmission electron microscope (TEM). Results Eleven rats were supplemented because of death after operation. In control group, a significant increase of the residual urine volume was observed with the extension of time (P lt; 0.05); in experimental group, an increase was observed at the first 3 months after operation, and then gradually decreased, showing significant differences between the other time point (P lt; 0.05) except between at 3 days and at 5 months after operation (P gt; 0.05); there was significant difference between control and experimental groups at other each time point (P lt; 0.05) except at 3 days, 1 month, and 2 months (P gt; 0.05). HE staining and Masson trichrome staining indicated that the muscle fibers arranged in disorder with gradually aggravated atrophy and gradually increased connective tissue in control group, while the shape of the detrusor muscle recovered with no increased connective tissue at 4, 5, and 6 months after operation in experimental group; there was significant difference in cross-sectional area of detrusor muscle and percentage of connective tissue between normal group and experimental group, and between normal group and control group at each time point (P lt; 0.05). In control group, the cross-sectional area of detrusor muscle decreased and the percentage of connective tissue increased with the extension of time (P lt; 0.05). In experimental group, the cross-sectional area of detrusor muscle decreased at the first 3 months and then increased, and the percentage of connective tissue increased slowly with the extension of time. There was no significant difference of cross-sectional area of detrusor muscle at the first 3 months between control and experimental groups (P gt; 0.05), but the values in experimental group were significantly higher than those in control group at 4, 5, and 6 months after operation (P lt; 0.05). There were significant differences of the percentage of connective tissue between control and experimental groups at each time point (P lt; 0.05). In control group, the amount of synaptic vesicles decreased in the NMJ with time passing; vacuole like structure was observed in NMJ at 3 months; there was almost no nerve ending at 6 months. In experimental group, the amount of synaptic vesicles decreased at 1 and 3 months after operation, but obviously increased at 6 months. Conclusion The reconstruction of bladder function with L5 nerve roots above the paraplegic plane can effectively inhibit the degeneration of detrusor muscle and improve its microstructural changes after medullary cone injury.
Objective To investigate the effects of chitosan/polyvinyl alcohol (PVA) nerve conduits for repairing radial nerve defect in Macaques. Methods Twelve adult Macaques weighing 3.26-5.35 kg were made the models of radial nerve defect (2 cm in length) and were randomly divided into 3 groups according to nerve grafting, with 4 Macaques in each group. Chitosan/PVA nerve conduit, non-graft, and autografts were implanted in the defects in groups A, B, and C, respectively. And the right radial nerves were used as normal control. At 8 months postoperatively, the general observation,electrophysiological methods, and histological examination were performed. Results At 8 months postoperatively, theregenerated nerve bridged the radial nerve defect in group A, but no obvious adhesion was observed between the tube and the peripheral tissue. The regenerated nerve had not bridged the sciatic nerve defect in group B. The adhesions between the implanted nerve and the peri pheral tissue were significant in group C. Compound muscle action potentials (CMAP) were detected in group A and group C, and no CMAP in group B. Peak ampl itude showed a significantly higher value in normal control than in groups A and C (P lt; 0.05), but there was no significant difference between groups A and C (P gt; 0.05). Nerve conduction velocity and latency were better in normal control than in groups A and C, and in group C than in group A, all showing significant differences (Plt; 0.05). The density of myl inated fibers in groups A and C was significantly lower than that in normal control (P lt; 0.05), but there was no significant difference between groups A and C (P gt; 0.05). The diameter and the myel in sheath thickness of the myl inated fibers in normal control were significantly higher than those in groups A and C, and in group C than in group A, all showing significant differences (P lt; 0.05). Conclusion The chitosan/PVA nerve conduits can promote the peripheral nerve regeneration, and may promise alternative to nerve autograft for repairing peripheral nerve defects.
Objective To investigate the sensation of the fingers innervated by the brachial plexus roots and provide the theoretic basis for diagnosis of a brachial plexus injury. Methods From June 2003 to January 2005，10 patients (8 males, 2 females; age,18-47 years) with complete brachial plexus avulsion were involved in this study, who underwent thecontralateral C7 nerve root transfer. The latency and amplitude of the sensory nerve actiopotential(SNAP) were record at the C5 T1 nerve roots when stimulation was given at the fingers.Results When the thumb and the index finger were stimulated and SNAP was recorded at all the roots of the brachial plexus in all the patients, we found that there was a higher amplitude and a shorter latency at the C5-7 roots than at the C8 and T1 roots(P＜0.05). When the middle finger was stimulated and SNAP was recorded at the C7,8 and T1 roots, we found that there was the highest amplitude and the shortest laency at the C7 root(P＜0.01). When the ring finger was stimulated and SNAP was recorded at the C7,8and T1 roots, we found that there was a higher amplitude and a shorter latency at the C8 and T1 roots than at the C7 root(P＜0.01). When the little finger was stimulated and SNAP was recorded at the C7,8and T1 roots, we found that there was the highest amplitude and the shortest latency at the T1 root(P＜0.01). ConclusionThe sense of the thumband the index finger is mainly nnervated by the C5-7 roots, the middle finger sense is mainly innervated by the C7 root, the ring finger sense is mainly innervated by the C8 and T1 roots, and the little finger sense is mainly innervated by the T1 root.
Objective To discuss the optimal approach to treat suprascapular nerve compression syndrome. Methods From January 2000 to June 2003, 8 cases of suprascapular nerve compression syndrome were treated by surgical intervention to cut the transverse scapular ligament through posterior approach. Of the 8 patients, there were 2 males and 6 females (age ranged from 21 to 53) with duration of 6 months to 3 years. The change of symptom, muscle power, and muscle atrophy after operation were observed. Results One week after operation, pain around the scapular disappeared, muscle power of supraspinatus and infraspinatus muscles recovered to normal. One, 6, 12 and 16 months after the operation, the patients were followed up. No recurrence was observed. Muscle atrophy didn’t recover.Conclusion To treat suprascapular nerve compression syndrome with operation through posterior approach is easy to operate. When the suprascapular nerve is entrapped in scapular notch, this approach is a good choice.
ObjectiveTo investigate the effect of electrospun chitosan/polylactic acid (ch/PLA) nerve conduit for repairing peripheral nerve defect in rats. MethodsNerve conducts loaded with ch/PLA was made by the way of electrospun. The mechanical property, hydrophility, biocompatibility were tested, and the scanning electron microscope was used to observe the ultrastructure. The same experiments were also performed on pure PLA nerve conducts as a comparison. Then, 54 Sprague Dawley rats were divided into 3 groups randomly, 18 rats in each group. Firstly, the 10 mm defects in the right sciatic nerves were made in the rats and were respectively repaired with ch/PLA (group A), autografts (group B), and no implant (group C). At 4, 8, and 12 weeks after operation, general observations, sciatic functional index (SFI), electrophysiological evaluation, wet weight of gastrocnemius and soleus muscles, histological examination, immunohistological analysis, and transmission electron microscopy were performed to evaluate the effects. ResultsCompared with pure PLA nerve conducts, the addition of chitosan could improve the mechanical property, hydrophility, biocompatibility, and ultrastructure of the nerve conducts. At 4 weeks postoperatively, the regenerated nerve bridged the nerve defect in group A. The SFI improved gradually in both group A and group B, showing no significant difference (P>0.05). Compound muscle action potentials and nerve conduction velocity could be detected in both group A and group B at 8 and 12 weeks after operation, and significant improvements were shown in both groups (P<0.05). The wet weight and myocyte cross section of gastrocnemius and soleus muscles showed no significant difference between group A and group B (P>0.05), but there was significant difference when compared with group C (P<0.05) at 12 weeks postoperatively. Immunohistological analysis revealed that S-100 positive Schwann cells migrated in both group A and group B, and axon also regenerated by immunohistological staining for growth associated protein 43 and neurofilaments 160. Transmission electron microscopy showed no significant difference in the diameter of nerve fiber between group A and group B (P>0.05), but the thickness of myelin sheath in group A was significantly larger than that in group B (P<0.05). ConclusionThe electrospun ch/PLA nerve conduits can effectively promote the peripheral nerve regeneration, and may promise an alternative to nerve autograft for repairing peripheral nerve defect.
ObjectiveTo evaluate the long-term effects on the lower limb function after S1 nerve root transection as dynamic source. MethodsBetween January 2007 and December 2011, 47 patients with atonic bladder dysfunction underwent S1 nerve root transposition to reconstrut the bladder function. There were 43 males and 4 females, with an average age of 40.7 years (range, 22-66 years). The locations were LS1 in 33 cases, LS2 in 5 cases, LS3 in 2 cases, TS12, LS1 in 3 cases, LS1, LS2 in 1 case, LS1, LS3 in 1 case, LS1, LS4 in 1 case, and LS2, LS3 in 1 case. The anastomosis of the SS2 or SS3 nerve root to S1 nerve root was performed from 4 to 24 months (mean, 8 months) after spinal cord injury. The strength of ankle plantar flexion was grade 4 in 5 cases and grade 5 in 42 cases before operation. ResultsThe strength of ankle plantar flexion had no obvious decrease (grade 4 or 5) in 31 cases, reduced 0.5 grade in 16 cases at 2 days after operation. All the patients were followed up 3-8 years (mean, 5.1 years). At 2 weeks after operation, the nerve electrophysiological examination showed neurogenic damage at operated side in most patients, including reduced amplitude tibial nerve in 19 cases, for common peroneal nerve in 13 cases, and for tibial nerve and common peroneal nerve in 9 cases. Except the velocity of common peroneal nerve (t=-1.881, P=0.093), the other electric physiological indexes showed significant differences between at pre- and post-operation (P<0.05). The muscle strength basically recovered to preoperative level (grade 4 or 5) during follow-up, and there was no impairment of lower limb function. ConclusionS1 transection has no significant effects on lower limb function, so S1 nerve can be used as dynamic nerve for nerve function reconstruction.