Objective To investigate the effect of the neuromuscular pedicle transplantation in prevention against atrophy in the denervated muscle. Methods Fortyeight SD rats were used to establish the right side tibialis anterior muscle denervation model. The long peroneal muscle neuromuscular pedicle was made as a treatment in 12 rats (Group A); the nerve shaft embedding was used in 12 rats (Group B); no treatment was used in 12 rats(Group C); the remaining 12 rats were used as normal controls (Group D). The gait analysis, electromyogram，muscle wet weight, and muscle fiber crosssectional area were used to determine and compare the effect of the operation at 6 and 12 weeks postoperatively. ResultsAt 6 weeks postoperatively, the parameters tested in Group A about the gait analysis (peroneal function index, PFI, －47.20±12.30), electromyogram, muscle wet weight (0.384 0±0.024 6 g)and muscle fiber cross-sectional area (1 040.98±120.54 μm2) were significantly better than those in Group C (PFI, -114.40±14.84; muscle wet weight, 0.173 0±0.019 1 g; muscle fiber cross-sectional area, 585.08±182.93 μm2,Plt;0.05), and the final two parameters were significantly better than those in Group B (0.294 0±0.056 4 g,763.92±82.68 μm2,Plt;0.05). At 12 weeks postoperatively, the musclefiber crosssectional area in Group A(1 360.10±261.45 μm2) had no significant difference from that in Group D (1 544.57±266.92 μm2，Pgt;0.05)，and most of the parameters tested in Group A were better than those in Groups B and C. Conclusion Neuromuscular pedicle transplantation has an excellent effect in prevention against atrophy in the denervated muscle, and the effect of neuromuscular pedicle transplantation is better than that of the nerve shaft embedding.
Objective To study and compare the effect of end-to-end and end-to-side neurorrhaphy between the reci pient’s musculocutaneous nerve and the donor’s ulnar nerve, and to observe the regeneration of peri pheral nerve and muscle refection. Methods Sixty male SD rats (weighing 200-250 g) were randomized into 2 groups (n=30 per group), and made the musculocutaneous nerve injury model. In group A, the donor’s nerve was transected for end-to-end neurorrhaphy.In group B, an epineurial window was exposed and the distal end of the muscle branch of musculocutaneous nerve was sutured to the side of the ulnar nerve. Electromyography was performed, biceps wet weight ratio, muscle fiber cross-sectional area, and count of myel inated nerve fiber (CMF) were measured at 4 and 12 weeks postoperatively. The behavior changes of the rats were observed. Results At 4 weeks, the nerve conduction velocity (NCV) and the latency ampl itude (AMP) of group A were significantly higher than those of group B (P lt; 0.05); at 12 weeks, there was no significant difference in the NCV and AMP between groups A and B (P gt; 0.05). At 4 and 8 weeks, there was no significant difference in biceps wet weight ratio and muscle fiber cross-sectional area between groups A and B (P gt; 0.05). At 4 weeks, the CMF was 230.15 ± 60.25 in group A and 160.73 ± 48.77 in group B, showing significant difference (P lt; 0.05); at 12 weeks, it was 380.26 ± 10.01 in group A and 355.63 ± 28.51 in group B, showing no significant difference (P gt; 0.05). Conclusion Both end-to-end and end-to-side neurorrhaphy have consistent long-term effect in repair of brachial plexus upper trunk injury.
Objective To reveal morphologic features and physiological function in compartments of human forearm muscles, and investigate the possibil ity of transplantation of neuromuscular compartments. Methods Sihler’ s neural staining technique was used to study the nerve branches distribution of forearm skeletal muscles in 5 human cadavers (aging26-39 years), including flexor carpi radial is, flexor carpi ulnaris (FCU), extensor carpi radial is brevis, extensor carpi ulnaris, palmaris longus (PL), flexor poll icis longus, pronator teres (PT). According to Wickiewicz’s methods, Ulnar compartment and radial compartment of forearm skeletal muscles above mentioned from 10 human cadvers were used to study the muscle architectural features. Results Each nerve branches run into the ulnar compartment and radial compartment respectively. There was statistically significant difference between the two physiological cross section areas (PSCA) of each neuromuscular compartment from forearm muscles(P lt; 0.05). Among them, PSCA of ulnar compartment of FCU was the largest. The PSCA of ulnar compartment of PT was the smallest. There was no statistically difference between the ratio (PSCA/muscle wet weight) of each neuromuscular compartment from forearm muscles (P gt; 0.05). As the ratio of PSCA to the muscle fiber length, the ulnar compartment of PT and the two compartments of PL had the highest one while the ulnar compartment of FCU had the smallest; and there was no statistically difference among the other neuromuscular compartments (P gt; 0.05). Conclusion Each of forearm muscles be divided into ulnar compartment and radial compartment and they have their own nerve supply. And there are significant differences in the physiological function in compartments of forearm muscles, which can be references in muscular compartment transplantation.
Objective To observe the delaying effect of neural stem cell (NSC) transplantation on denervated muscle atrophy after peri pheral nerve injury, and to investigate its mechanism. Methods NSCs were separated from the spinal cords of green fluorescent protein (GFP) transgenic rats aged 12-14 days mechanically and were cultured and induced to differentiate in vitro. Thirty-two F344 rats, aged 2 months and weighed (180 ± 20) g, were randomized into two groups (n=16 per group). The animal models of denervated musculus triceps surae were establ ished by transecting right tibial nerve and commom peroneal nerve 1.5 cm above the knee joints. In the experimental and the control group, 5 μL of GFP-NSCsuspension and 5 μL of culture supernatant were injected into the distal stump of the tibial nerve, respectivel. The generalcondition of rats after operation was observed. At 4 and 12 weeks postoperatively, the wet weight of right musculus tricepssurae was measured, the HE staining, the Mallory trichrome staining and the postsynaptic membrane staining were adopted for the histological observation. Meanwhile, the section area of gastrocnemius fiber and the area of postsynaptic membrane were detected by image analysis software and statistical analysis. Results The wounds in both groups of animals healed by first intension, no ulcer occurred in the right hind l imbs. At 4 and 12 weeks postoperatively, the wet weight of right musculus triceps surae was (0.849 ± 0.064) g and (0.596 ± 0.047) g in the experimental group, respectively, and was (0.651 ± 0.040) g and (0.298 ± 0.016) g in the control group, respectively, showing a significant difference (P lt; 0.05). The fiber section area of the gastrocnemius was 72.55% ± 8.12% and 58.96% ± 6.07% in the experimental group, respectively, and was 50.23% ± 4.76% and 33.63% ± 4.41% in the control group, respectively. There were significant differences between them (P lt; 0.05). Mallory trichrome staining of muscle notified that there was more collagen fiber hyperplasia of denervated gastrocnemius in the control group than that in the experimental group at 4 and 12 weeks postoperatively. After 12 weeks of operation, the area of postsynaptic membrane in the experimental group was (137.29 ± 29.14) μm2, which doubled that in the control group as (61.03 ± 11.38) μm2 and was closer to that in normal postsynaptic membrane as (198.63 ± 23.11) μm2, showing significant differences (P lt; 0.05). Conclusion The transplantation in vivo of allogenic embryonic spinal cord NSCs is capable of delaying denervated muscle atrophy and maintaining the normal appearance of postsynaptic membrane, providing a new approach to prevent and treat the denervated muscle atrophy cl inically.
Objective To explore the effect of basic fibroblast growth factor（bFGF）and epidermal growth factor（EGF）on the growth of muscle derived stem cells(MDSCs). Methods MDSCs were isolated from hindlimb muscle of 15 new born Kunming mice through serial preplates. 2% fetal bovine serum-containing DMEM was used to induce MDSCs to differentiate into skeletal muscle lineage. The expressions of stem cell marker Sca-1 and skeletal musclecell marker αSarcomeric actin were examined by immunocytochemistry. The effect of bFGF and EGF on the proliferation of MDSCs was determined by MTT colorimetric microassay. The solo effect of bFGF or EGF at different concentrations (6.25,12.50, 25.00, 50.00, and 100.00 ng/ml) was examined at 96 h and the combined effect (100.00 ng/ml) was examined at 24,48,72 and 96 h.Results MDSCs were successfully isolated from the hindlimb of neonatal mice. Over 90% of MDSCs showed Sca-1 positive immunoreactivity. MDSCs could give rise to α Sarcomeric actin positive myotubes in differentiation cultures. The proliferative effect of bFGF and EGF on MDSCs increased with the elevated concentration.bFGF began to show significant proliferative effect at 12.50 ng/ml (P＜0.05). The effect increased significantly when the concentration reached 25.00 ng/ml from 12.50 ng/ml (P＜0.01) and reached a saturation point. The effect at 50.00 ng/ml or 100.00 ng/ml showed no significant increase when compared with thatat 25.00 ng/ml. EGF had a similar effect to bFGF except that the saturation concentration was 50.00 ng/ml. EGF showed significant effect at 72 h and bFGF at 96 h (Plt;0.01). When they were applied together, significant effect was shownat 24 h (Plt;0.01) and much higher effect was observed at 48, 72 and 96 h (Plt;0.05). Conclusion Both bFGF and EGF can promote the proliferation of MDSCs. The combined application reacts faster and ber.
ObjectiveMitochondrial encephalomyopathy is a series of diseases that drag in central nervous system and generalized muscles. The pathogenesis of the disease is lack of ATP for the dysfunction of mitochondria. The misdiagnosis rate of the disease is high and the purpose of this study is to improve the recognition and diagnosis of mitochondrial encephalomyopathy and thus, clinicians could take rational treatment in time and improve patients' prognosis. MethodsThe clinical data of 11 patients with mitochondrial encephalomyopathy were analyzed including the physical data, clinical presentations, laboratory data, neuroimaging findings, muscle biopsy, genetic testing, treatment and prognosis. Reviewing literature and summarizing the clinical characteristics of mitochondrial encephalomyopathy. ResultsAmong the 11 patients with mitochondrial encephalomyopathy, the mean age was 17 years old. 1 case had family history. 7 cases were misdiagnosed in the first clinic visit. The onset of the 11 cases, 9 were paroxysmal and 2 were hidden. In the course, 10 cases had an epileptic seizure. Among the 9 cases who took the determination of serum lactate, 8 was in high level.9 cases had MRI examination and all found abnormality, 10 patients had EEG examination, and 9 cases found abnormality, 6 cases had muscle biopsy and all found the ragged red fiber(RRF). 6 cases had molecular genetic testing, and all found mutations in mitochondrial DNA. Among the 10 cases who had epileptic seizure, 3 cases can be controlled with single kind of antiepileptic drug. The other 7 cases had a recurrence of epilepsy with single kind of antiepileptic drugs, but can be cotrolled after drug adjusting or drug combination. ConclusionMitochondrial encephalomyopathy is often accompanied by seizure, which is usually found in children, and also often accompanied by systemic muscle symptoms. The clinical manifestations of the disease is not typical, but is complex and varied symptoms, so the clinical misdiagnosis rate is high. Mitochondrial encephalomyopathy mainly involves the main intracranial artery distribution area (parietal lobe, temporal lobe, occipital lobe, etc.) in central nervous system, and can involve more than one part. Patients with mitochondrial myopathy brain are usually detected the elevation of serum lactate levels, but if the lactic acid level is normal, it does not rule out the possibility of the disease, the confirmation of the disease is mainly by muscle biopsy or genetic tests. There is no specific treatment for mitochondrial encephalomyopathy till now, and it still give priority to symptomatic treatment. And the prognosis is poorer.
Objective To provide the anatomical basis of contralateral C7 root transfer for the recovery of the forearm flexor function. Methods Thirty sides of adult anti-corrosion specimens were used to measure the length from the end of nerves dominating forearm flexor to the anastomotic stoma of contralateral C7 nerve when contralateral C7 nerve transfer was used for repair of brachial plexus lower trunk and medial cord injuries. The muscle and nerve branches were observed. The length of C7 nerve, C7 anterior division, and C7 posterior division was measured. Results The length of C7 nerve, anterior division, and posterior division was (58.8 ± 4.2), (15.4 ± 6.7), and (8.8 ± 4.4) mm, respectively. The lengths from the anastomotic stoma to the points entering muscle were as follow: (369.4 ± 47.3) mm to palmaris longus, (390.5 ± 38.8) mm (median nerve dominate) and (413.6 ± 47.4) mm (anterior interosseous nerve dominate) to the flexor digitorum superficialis, (346.2 ± 22.3) mm (median nerve dominate) and (408.2 ± 23.9) mm (anterior interosseous nerve dominate) to the flexor digitorum profundus of the index and the middle fingers, (344.2 ± 27.2) mm to the flexor digitorum profundus of the little and the ring fingers, (392.5 ± 29.2) mm (median nerve dominate) and (420.5 ± 37.1) mm (anterior interosseous nerve dominate) to the flexor pollicis longus, and (548.7 ± 30.0) mm to the starting point of the deep branch of ulnar nerve. The branches of the anterior interosseous nerve reached to the flexor hallucis longus, the deep flexor of the index and the middle fingers and the pronator quadratus muscle, but its branches reached to the flexor digitorum superficials in 5 specimens (16.7%). The branches of the median nerve reached to the palmaris longus and the flexor digitorum superficial, but its branches reached to the deep flexor of the index and the middle fingers in 10 specimens (33.3%) and to flexor hallucis longus in 6 specimens (20.0%). Conclusion If sural nerve graft is used, the function of the forearm muscles will can not be restored; shortening of humerus and one nerve anastomosis are good for forearm flexor to recover function in clinical.
The automatic recognition technology of muscle fatigue has widespread application in the field of kinesiology and rehabilitation medicine. In this paper, we used surface electromyography (sEMG) to study the recognition of leg muscle fatigue during circuit resistance training. The purpose of this study was to solve the problem that the sEMG signals have a lot of noise interference and the recognition accuracy of the existing muscle fatigue recognition model is not high enough. First, we proposed an improved wavelet threshold function denoising algorithm to denoise the sEMG signal. Then, we build a muscle fatigue state recognition model based on long short-term memory (LSTM), and used the Holdout method to evaluate the performance of the model. Finally, the denoising effect of the improved wavelet threshold function denoising method proposed in this paper was compared with the denoising effect of the traditional wavelet threshold denoising method. We compared the performance of the proposed muscle fatigue recognition model with that of particle swarm optimization support vector machine (PSO-SVM) and convolutional neural network (CNN). The results showed that the new wavelet threshold function had better denoising performance than hard and soft threshold functions. The accuracy of LSTM network model in identifying muscle fatigue was 4.89% and 2.47% higher than that of PSO-SVM and CNN, respectively. The sEMG signal denoising method and muscle fatigue recognition model proposed in this paper have important implications for monitoring muscle fatigue during rehabilitation training and exercise.
In order to realize the quantitative assessment of muscle strength in hand function rehabilitation and then formulate scientific and effective rehabilitation training strategies, this paper constructs a multi-scale convolutional neural network (MSCNN) - convolutional block attention module (CBAM) - bidirectional long short-term memory network (BiLSTM) muscle strength prediction model to fully explore the spatial and temporal features of the data and simultaneously suppress useless features, and finally achieve the improvement of the accuracy of the muscle strength prediction model. To verify the effectiveness of the model proposed in this paper, the model in this paper is compared with traditional models such as support vector machine (SVM), random forest (RF), convolutional neural network (CNN), CNN - squeeze excitation network (SENet), MSCNN-CBAM and MSCNN-BiLSTM, and the effect of muscle strength prediction by each model is investigated when the hand force application changes from 40% of the maximum voluntary contraction force (MVC) to 60% of the MVC. The research results show that as the hand force application increases, the effect of the muscle strength prediction model becomes worse. Then the ablation experiment is used to analyze the influence degree of each module on the muscle strength prediction result, and it is found that the CBAM module plays a key role in the model. Therefore, by using the model in this article, the accuracy of muscle strength prediction can be effectively improved, and the characteristics and laws of hand muscle activities can be deeply understood, providing assistance for further exploring the mechanism of hand functions.
ObjectiveTo evaluate the effects of nerve growth factor (NGF) on angiogenesis and skeletal muscle fiber remodeling in ischemic hindlimbs, and study the relationship of NGF and vascular endothelial growth factor (VEGF) to angiogenesis. MethodsEighteen mice were randomly allocated to normal control group (n=6), blank control group (n=6), and NGF gene transfection group (n=6). The left hindlimb ischemia model was established by ligating the femoral artery. NGF plasmid (125μg) was injected into the mouse ischemic gastrocnemius in the NGF gene transfection group. The same volume of normal saline (200μL) was injected into the mouse ischemic gastrocnemius in the blank control group. The gastrocnemius of left hindlimb was harvested under the condition of peritoneal cavity anesthesia on the 21th day after operation, and then the mice were sacrificed. The gastrocnemius of three groups were tested by hematoxylin-eosin staining, proliferating cell nuclear antigen (PCNA) and CD34 were determined by immunohistochemistry staining. Skeletal muscle fiber type was tested by myosin ATPase staining. NGF and VEGF protein expression were detected by enzyme linked immunosorbent assay. ResultsOn the 21th day after surgery, compared with the blank control group, the skeletal muscle atrophy degree was weaker, the functional assessment score was significantly lower (P < 0.05), the endothelial cell proliferation index, capillary density, the typeⅠskeletal muscle fiber proportion, NGF and VEGF expression were significantly higher (P < 0.05) in the NGF gene transfection group. ConclusionsNGF gene transfection could promote NGF and VEGF expression and angiogenesis in ischemic hindlimbs, and induce typeⅠskeletal muscle fibers formation in ischemic hindlimbs. The molecular regulation mechanism still needs to be further studied.