Objective To observe the ultrastructural characteristics of human retinal progenitor cells cultured in vitro. Methods Six 5-month-old human fetuses（12 eyes）without eye diseases were selected. Retinal progenitor cells from the retina of one eye of each fetus were cultured in vitro，and observed by transmission electronic microscopy（TEM）; while those from the other eye were directly observed by TEM. Results Abundant heterochromatin were found in the karyon of 5-month embryonic retinal neuroepithelial cells，and the figure of the karyons was irregular.A few scattered initial cells were seen in retinal neuroepithelial layer with large karyon，smooth surface，abundant euchromatin，and distinct nucleolus.The human retinal progenitor cells cultured in vitro had the same ultrastructural characteristics as the initial cells:with huge karyon which almost occupied the whole cell，little cytoplasm，distint nucleolus，abundant euchromatin，and little heterochromatin.The cells clung to each other in the neural globoid cell mass.The size of the outer cells was large，and karyokinesis could be found. Conclusion The cultured human retinal progenitor cells are provided with the same ultrastructure characteristics as the initial cells. (Chin J Ocul Fundus Dis, 2006, 22: 185-187)
Objective To explore the method that can inducethe mesenchymal stem cells (MSCs) to differentiate into the neuronlike cells in vitro．Methods The neuron-like cells were isolated froman SD rat (age, 3 months; weight, 200 g). They underwent a primary culture; theinduced liquid supernatant was collected, and was identified by the cell immunohistochemistry. The C3H1OT1/2 cells were cultured, as an MSCs model, and they were induced into differentiation by β-mercaptoethanol (Group A) and by the liquid supernatant of the neuron-like primary cells (Group B), respectively. The cells were cultured without any induction were used as a control (Group C). Immunohistochemistrywas used to identify the type of the cells． Results The result of the immunochemistry showed that the cells undergoing the primary culture expressed the neurofilament protein (NF) and the neuronspecific enolase (NSE), and they were neuron-like cells. β-mercaptoethanol could induce the C3H1OT1/2 cells toexpress NF and NSE at 2 h, and the expression intensity increased at 5 h. The liquid supernatant of the primarily-cultured neuron-like cells could induce theC3H1OT1/2 cells to express NF and NSE at 1 d, but the expression intensity induced by the liquid supernatant was weaker than that induced by β-mercaptoethanol. The positivity rate and the intensity expression of NSE were higher than those of NF. Conclusion MSCs can differentiate into the neuron-like cells by β-mercaptoethanol and the microenvironment humoral factor, which can pave the way for a further study of the differentiation of MSCs and the effectof the differentiation on the brain trauma repair.
Objective To investigate the possibility of commitment differentiation of embryonic stem cells induced by the medium of cultured retinal neurons of SD rats. Methods The medium from cultured retinal neurons of SD rats were collected, sterilized and mixed with DMEM medium according to 2∶3 proportion, ES cells were cultured with these mixed medium and were observed under the phase contrast microscope daily, the induced cells were identified by NF immunohistochemistry methods. Results The ES cells cultured with these mixed medium can differentiate into neuron-like structure, and the induced cells were positive in NF immunofluorescence staining. Conclusion The medium from cultured retinal neurons of SD rats can induce ES cells commitment differentiation into neuron-like structure. (Chin J Ocul Fundus Dis, 2002, 18: 134-136)
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.
Objective To observe the effects of minocycline to the viability and apoptosis of ratprime;s retinal neuron cells (RNC) under pressure, and to investigate the neuroprotective mechanisms of minocycline against the RNC damage. Methods Establish a model of ratprime;s RNs under pressure cultured in vitro, the protective effect of minocycline is observed by different methods, including observing the morphology of the cells, evaluating the cellsprime; viability by methyl thiazolyl tetrazolium (MTT) colorimetry assay, and detecting the cellular apoptosis with acridine orange/ethidium bromide (AO/EB) double staining by fluorescence microscopy. Immunocytochemistry was used to detect the expression of iNOS and caspase-3 in the cells. Results Obvious morphology changes of RNC were found in cells under pressure compared with the control; the viability of RNC decreased and cellular apoptosis was found in 53.93% cells. The cellular morphology improved in the cells treated by 20 mu;mol/L minocycline, the cellular viability significantly increased, and the cellular apoptosis was found in 17.29% cells. In addition, the expression of iNOS and caspase3 in the treated cells decreased compared with which in the pressured group. Conclusion Minocycline with a certain concentration can effectively inhibit pressureinduced damage and apoptosis of RNC of rats, and the inhibitory effect on expression of iNOS and capases-3 may be the underlying mechanism.
Objective To investigate the application of Magnetoencephalograph (MEG), Wada test combined with neuronavigation in the surgical treatment of frontal and temporal epilepsy caused by focal cortical dysplasia (FCD ). Methods The epileptogenic focus and IQ, memory and language examination were performed in 34 patients with frontal and temporal epilepsy caused by FCD. MEG and Wada test were conducted to determine the language and memory advantage hemisphere, and to clarify the scope and memory function of language function areas. Operation was guided by the Medtronic stealhealth 7 surgical navigation system (USA) to remove the FCD and protect nerve function. IQ, memory and language examination were measured 1 year after operation, and the difference was observed before and after operation. The postoperative follow-up was 23 ~ 46 months, curative effect of epilepsy was determined according to the international anti-epilepsy union Engel’s standard. Results Thirty-four patients with epilepsy (21 temporal lobe epilepsy and 13 frontal lobe epilepsy) were included in this study. The examination process of MEG and Wada test was smooth. MEG can accurately locate the position of language function area. Twenty-eight patients’ dominant hemisphere of language was on the left and 6 was on the right side. Wada test can evaluate the patient’s memory function. Twenty-three patients’ dominant hemisphere of memory was located on the left, 8 on the right and 3 on the bilateral hemisphere. Compared with the dominant hemisphere and nondominant hemisphere, the memory score was significantly different (P<0.05). Statistics showed that the verbal IQ and total IQ increased (P<0.05)1 year after operation, but there was no significant change in memory IQ and Performance IQ (P>0.05). FCD patients recovered well without language, memory and limb impairment. The curative effect of epilepsy: 15 cases of Engel’sⅠgrade, 14 cases of Engel’sⅡgrade and 5 cases of Engel’s Ⅲ grade. Conclusion MEG, Wada test combined with neuronavigation was of important value in locating and guiding the surgical resection of FCD in patients with refractory frontal and temporal epilepsy, protecting cortical function, avoiding severe postoperative complications, and improving the therapeutic effect of epilepsy.
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.
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.
ObjectiveTo investigate the clinical value of neuronavigation combined with intraoperative ultrasound in the resection of glioma with epilepsy.MethodsTo review and analyze the clinical data of 47 glioma patients with epilepsy treated by intraoperative ultrasound-assisted neuronavigation during the period from June 30, 2012 to June 30, 2014, and to compare and analyze the extent of gliom resection and the control of epilepsy before and after surgery.ResultsAll the patients had no hematoma, infection or hemiplegia. MRI was reviewed 48 hours after surgery and MRI showed complete resection in 34 cases and subtotal resection in 13 cases. One year after the operation, the seizure control was evaluated. Engel’s class I, 17 cases, Engel’s class II, 20 cases, Engel’s class III, 10 cases. When the nerve function is protected, the tumor is removed and the epileptic seizure is controlled, and the clinical effect is remarkable.ConclusionsNeuronavigation is helpful to locate the lesion and brain functional area and design the surgical approach before surgery, and to guide the location and boundary of the lesion and functional area during surgery. Intraoperative ultrasound has many advantages such as noninvasive, repeatable and real-time examination. Neuronavigation combined with intraoperative ultrasound can achieve maximum resection of gliomas and epileptogenic foci and reduce the incidence of postoperative neurological dysfunction in patients.
Retinal neuronal cells are crucial in the formation of vision. Injury or death of these cells may lead to irreversible damage to visual function due to their low regenerative capacity. The P2X7 receptor is a trimeric adenosine triphosphate (ATP)-gated cation channel. Recent studies have shown that P2X7 receptor plays a role in retinal neuronal death. In a series of animal models, when exposed to conditions of hypoxia or ischemia, elevated ocular pressure, trauma and exogenous agonists, P2X7 receptor activated by extracellular ATP can cause death of retinal neuronal cells such as retinal ganglion cells and photoreceptor cells through direct or indirect pathways. Blocking the expression and function of P2X7 receptor by its specific antagonist and gene knocking-out, the loss of retinal neuronal cells is significantly attenuated. P2X7 receptor may become a potential novel neuroprotective target for diseases related to the loss of retinal neurons.