OBJECTIVE: To research the protective effect of Schwann cell and extracellular matrix (ECM) gel on neurons in dorsal root ganglion. METHODS: 1. Schwann cells were seeded into 30% ECM at 1 x 10(8)/ml and then implanted into PLA hollow fiber conduits to repair 10 mm length defects of rat sciatic nerve, and histological observation was taken at 8 and 12 weeks after operation. 2. To observe the survival of Schwann cells, Schwann cells labeled BrdU were seeded into 30% ECM at 1 x 10(8)/ml and then implanted into PLA hollow fiber conduits to repair 10 mm length defects of rat sciatic nerve. Histological observation and immunohistochemical method stained with BrdU were done at 3 and 6 weeks after operation. RESULTS: 1. When seeded into ECM gel and transplanted into rats, most of the Schwann cells survived to 3 weeks and a part of them survived up to 6 weeks. 2. The survival neuron ratios of Schwann cells with ECM gel group and ECM gel group were 83.5% and 81.3% respectively, and significantly higher than that of saline group (72.9%, P lt; 0.05). CONCLUSION: When seeded into ECM gel and transplanted into rats, most of the Schwann cells survive and protect 83.5% neurons in dorsal root ganglion from retrograde death.
Purpose To investigate the characteristics of intraocular growth of mice embryonic stem cells (ESC) in nude mice. Methods The undifferentiated murine ESC in vitro were transplanted into the eyes of nude mice.Mophological and immunohistochemical examinations were implemented. Results Two to three days after transplantation,yellowish-white granules and masses were seen inside the anterior chamber and vitreous cavity and enlarged gradually.Morphological examination showed that there were undifferentiated cells and differentiated cells in anterior chamber and vitreous cavity.The morphology and alignment of some differentiated cells were similar to those of the retina of nude mice.The cells were highly positive in NSE staining. Conclusion The transplanted ESC could grow in the eyes of nude mice and differentiate into neurons and retina-like structure. (Chin J Ocul Fundus Dis，2000，16：213-284)
Objective To investigate the relationship between electrophysiological and morphological properties of neurons in visual cortex of developing rat, speculate the coincided degree between electrophysiological and morphological change and realize the mechanism of normal visual development. Methods Whole cell patch-clamp recording and intracellular staining were used to acquire cellular microelectrode recording in visual cortex from Sprague-Dawley rats (4~28 days old). The histological process was made. Results The differences of electrical feature between pyramidal cells and non-pyramidal cells were significant. The morphological maturity degree is different in developing visual cortex. Conclusion The different function of pyramidal and non-pyramidal cells in local integrition is reflected by their electrical feature in the process of visual development. In critical period of visual development, the coincision degree of the electrophysiological and morphological change in visual cortex is larger than that in the subcortex constructure. (Chin J Ocul Fundus Dis, 2001,17:289-292)
Objective To investigate the effect of olfactory ensheathing cell culture medium (OECCM) on the growth of spinal cord neurons and its protective effect on the injured neurons by H2O2, and to disscuss the probable protective mechanisms of olfactory ensheathing cells (OECs). Methods The primary olfactory ensheathing cells (OECs) were isolated from olfactory bulb of adult SD rat, and OECCM were prepared. The morphology of OECs was observed by inverted phase contrast microscope, identified by rabbit-antiratlow-affinity nerve growth factor p75 (NGFRp75), and its purity were calculated.Primary spinal cord neurons were cultured from 15 to 17 days pregnant SD rats, and injury model of neurons were prepared by H2O2. OECCM and control culture medium were added into the normal spinal neurons (groups A, B). OECCM and control culture medium were added into the injured spinal neurons by H2O2 (groups C, D). In groups A and C, 200 μL of control culture medium was used; in groups B and D, 100 μL of control culture medium and 100 μL of OECCM were used. Then the growth index such as average diameter of neuron body, the number and length of neuron axons were measured. The viabil ities of normal and injured neurons were assessed by MTT. Results OECs showed bipolar or tripolar after 6-9 days of culture. Primary spinal cord neurons were round and bigger, and neuron axons grew significantly and showed bipolar after 5-7 days of culture. The immunocytochemisty of OECs by NGFRp75 showed that membrane were stained. The degree of purity was more than 90%. Primary spinal cord neurons grew well after 6-9 days of culture, and compared with group A, neurons of group B grew b, whose cell density and diameter were bigger. The average diameter of neuron body, the number and length of neuron axons were (33.38 ± 6.80) D/μm, (1.67 ± 0.80), and (91.19 ± 62.64) L/μm in group A, and (37.39 ± 7.28) D/μm, (1.76 ± 0.82), and (121.33 ± 81.13) L/μm in group B; showing statistically significant differences (P lt; 0.05). The absorbency (A) value of neurons was 0.402 0 ± 0.586 9 in group A and 0.466 0 ± 0.479 0 in group B; showing statistically significant difference (P lt; 0.01). After 2 hours of injury by H2O2, the cell density of spinal cord neurons decreased, and neuron axons shortened. The A value of injured neurons was 0.149 0 ± 0.030 0 in group C and 0.184 0 ± 0.052 0 in group D, showing statistically significant difference (P lt; 0.01). Conclusion The results above suggest that OECCM could improve the growth of spinal cord neurons and protectthe injured neurons. The neurotrophic factors that OECs secrete play an important role in the treatment of spinal cord injury.
Objective To investigate the distribution of rats’ pelvic muscles motoneurons innervated by artifical somatic-autonomic reflex arc. Methods Thirty-five SD rats were randomly divided into normal group (n=10) and model group (n=25). The rats in the normal group were given no treatment. In the normal group, the artifical somatic-autonomic reflex arc was established. Six months after establishing the model, external urethral sphincter (EUS), ischiocavernosus (IC), bulbocavernosus (BS) and external anal sphincter (EAS) of the rats in normal group(n=10) and of the rats in model group A (n=20) were injected with fluorogold (FG). The reversal neural tracing was done. FG positive neural cells were observedby fluorescent microscope. Malt agglutinator binding horseradish peroxidase (WGA-HRP) was injected into L4 spinal cord of the rats in model group B (n=5) as the anterograde tracer. After being treated with TMB-HRP reaction, the axon endings in the neuromuscular junction in pelvic striated muscles (EUS, IC, BS, EAS) were investigated with light microscopes. Results In normal group, EUS and IC injections resulted in transport of FG to neurons in the dorsolateral nucleus (DL) of the ventral horn of the L5～S1, and BS and EAS in the dorsomedial nucleus (DM) of ventral horn in the L5～S1. In the model group A, EUS, IC, BS andEAS injections resulted in transport of FG to neurons in the left ventral horn in the L4. In model group B, after WGA-HRP was injected into the L4 left ventral horn, HRP positive axon terminals were observed in the EUS, IC, BS and EAS. Conclusion In the normal rats, the pelvic striated muscles motoneurons locate in the ventral horn of L5～S1. In the model rats, the pelvic striated muscles motoneurons innervated by artificial somatic-autonomic reflex arc locate in the ventral horn of the L4. After the artificial somaticautonomic reflex arc is established, the isomerous nerve fiber innervates EUS, IC, BS and EAS.
Objective To study the expression and its significance of bcl-2 associated death (bad) gene in human optic nerves from traumatic atrophic eyeballs. Methods The optic nerves from 8 normal human donor eyes and 31 traumatic atrophic eyes were studied by immunohistochemistry technique. Results Bad protein was positively expressed in the normal optic nerve myelin sheath and residual myelin portions of optic nerve tissues from traumatic atrophic eyes. The expression of bad protein in the residual portions of myelin sheath was stained significantly ber than that in normal optic nerves (P＜0.05)。The pathological durations for ocular atrophy was not co-related with the quantites of expression of bad protein. There was no significant difference between pathogenic causes of ocular atrophies and the quantites of bad expression (P＞0.05). Conclusion Bad might possess the function of promoting the optic nerve atrophy processes in traumatic atrophic eyes. (Chin J Ocul Fundus Dis, 2002, 18: 276-278)
ObjectiveTo study the clinical features of children with seizures as core symptoms of neuronal surface antibody syndromes. MethodsThe clinical data of neuronal surface antibody syndromes between December 2015 and December 2016 were obtained and analyzed. All children presented to hospital with seizures as core symptoms. ResultsThere were 1 male and 9 females in this study. The ages ranged from 3 years to 13 years. The disease course was between 3 and 14 days. All children presented to hospital with seizures as core symptoms.Two children had tonic seizures. one had tonic-clonic seizure. Seven had partial seizures. Among them, six children had status epilepticus and cluster attack. The other symptoms in the course of the disease were psychiatric symptoms and extrapyramidal symptoms.The anti-NMDAR antibody were found in 9 patients' CSF and blood. The LGI1 antibody was found in one patients' CSF and blood.The EEG test of 7 patients showed slow wave and sharp slow wave. Two showed spike wave. One showed slow wave.The MRI test of one patient showed abnormal. Ten cases were treated with IVIG and methylprednisolone during acute stage. The patients had been followed up for 3 to 6 months. Eight of them recovered completely. Two cases had seizures. Two cases diagnosed with anti-NMDAR related epilepsy received sound effects after treated with cyclophosphamide. ConclusionsConvulsion may be the first common symptom of neuronal surface antibody syndromes in children. Immune factors should be screened when children with acute seizures and status epilepticus. Accompanying psychiatric symptoms, autoimmune epilepsy should be considered. The most common neuronal surface antibody in children with neuronal surface antibody syndromes is NMDAR antibody. EEG usually shows slow wave and sharp slow wave during seizures. Brain MRI is usually normal. Immunotherapy is effective in the majority of patients as the first line treatment. When the first-line treatment failed, second-line immunotherapy such as cyclophosphamide shock therapy on a regular basis is helpful.
Objective To observe the serumlevel of neuron-specific enolase( NSE) in patients with pulmonary encephalopathy and its changes after treatment with mechanical ventilation. Methods Twentyone patients with pulmonary encephalopathy were enrolled. Glasgow coma scale( GCS) , serumNSE level, and arterial blood gas were evaluated at three time-points: before mechanical ventilation, after 12 hours mechanical ventilation, and the moment of consciousness. Results 18 patients recovered consciousness, and 3 patients remained in persistent coma and died. GCS and arterial blood gas improved obviously after 12 hours mechanical ventilation. Meanwhile, the serumNSE concentration decreased significantly after 12 hours mechanical ventilation [ ( 24. 54 ±6. 65) μg/L] and at the moment of consciousness [ ( 14. 19 ±2. 91) μg/L] compared with before mechanical ventilation( P lt; 0. 05, P lt; 0. 01) . Conclusion Dynamic measurment of serumNSE may be a useful biomarker for assessing the severity of cerebral injury and predicting prognosis.
Objective To research the protective effects of different allogeneic cells injected into denervated muscles on ventricornual motor neuron. Methods Thirty-six adult female SD rats, weighting 120-150 g, were individed into four groups randomly and each group had nine. Left ischiadic nerves of all the SD rats, which were cut down on germfree conditions,were operated by primary suture of epineurium. Different cells were injected into the triceps muscles of calf in each group after operation with once a week for 4 weeks:1 ml Schwann cells (1×106/ml) in group A, 1 ml mixed cells ofSchwann cells and myoblast cells (1∶1,1×106/ml) in group B, 1 ml extract from the mixed cells of Schwann cells, myoblast cells and endotheliocytes (1∶1∶1,1×106/ml)in group C,and 1 ml culture medium without FCS as control group(group D). The observation of enzymohistochemistry and C-Jun expression in the ventricornual motor neuron was made after three months of operation. Results After 3 months of operation, the expressions of C-Jun in groups A, B and C were superiorto that in group D; the number of neuron was more than that of group D. The expressions of C-Jun in the ventricornual motor neuron were as follows: 128.591±0.766 in group A, 116.729±0.778 in group B, 100.071±2.017 in group C and 144.648±2.083 in group D; showing statistically significant difference between groupsA, B, C and D(P＜0.01). Enzymohistochemistry showed the well outlined and wellstacked cell body of neuron in groups A, B and C, and illdefined boundary of cytoplasm and nucleus. There was statistically significant defference in enzyme activity of the ventricornual motor neuron between groups(P＜0.01). Conclusion All of the Schwann cells,mixed cells of Schwann cells with myoblast cells,and the extract from Schwann cells, myoblast cells and endotheliocytes can protect the ventricornual motor neuron. And the protectiveeffect of the extract from Schwann cells, myoblast cells and endotheliocytes is superior to that of Schwann cells and mixed cells.
Repeated transcranial magnetic stimulation (rTMS) is one of the commonly used brain stimulation techniques. In order to investigate the effects of rTMS on the excitability of different types of neurons, this study is conducted to investigate the effects of rTMS on the cognitive function of mice and the excitability of hippocampal glutaminergic neurons and gamma-aminobutyric neurons from the perspective of electrophysiology. In this study, mice were randomly divided into glutaminergic control group, glutaminergic magnetic stimulation group, gamma-aminobutyric acid energy control group, and gamma-aminobutyric acid magnetic stimulation group. The four groups of mice were injected with adeno-associated virus to label two types of neurons and were implanted optical fiber. The stimulation groups received 14 days of stimulation and the control groups received 14 days of pseudo-stimulation. The fluorescence intensity of calcium ions in mice was recorded by optical fiber system. Behavioral experiments were conducted to explore the changes of cognitive function in mice. The patch-clamp system was used to detect the changes of neuronal action potential characteristics. The results showed that rTMS significantly improved the cognitive function of mice, increased the amplitude of calcium fluorescence of glutamergic neurons and gamma-aminobutyric neurons in the hippocampus, and enhanced the action potential related indexes of glutamergic neurons and gamma-aminobutyric neurons. The results suggest that rTMS can improve the cognitive ability of mice by enhancing the excitability of hippocampal glutaminergic neurons and gamma-aminobutyric neurons.