Objective To study the effect of brain-derived neurotrophic factor (BDNF) on the environmental nutrition and neural differentiation of the transplanted stem cells under hypothermia.Methods The BDNF gene mediated by liposome was transfected into 293T cell line, and ELISA assay was applied to find the peak time of BDNF expression. When BDNF was highly expressed, the supernatant was collected for establishment of SD rat models of brain injury. The rats were divided into Group A (stem cell transplantation group) and Group B (stem cell transplantation and BDNF group). Rats in both groups were under hypothermia treatment for five days. Four and eight days later ( three days from rewarming), rat brain tissues were obtained to detect the expressions of proliferating cell nuclear antigen (PCNA), nestin, neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) by immunohistochemical method and to detect the apoptosis by in situ hybridization. Finally, the nerve function scores were obtained for evaluation of the nerve function. Results The ELISA showed that the high level of BDNF expression was at 48 to 60 hours after gene transfection. PCNA and nestin were highly expressed, while NES and GFAP showed nil or low level of expression in both groups at the fourth day after hypothermia, with little apoptotic cells especially in the Group B (P ＜0.05). The expressions of PCNA and nestin were decreased, but the expressions of NSE and GFAP were increased at the third day after rewarming. The positive rate of NSE expression in the Group B was much higher and the apoptotic cells were much less compared with the Group A ( P ＜ 0. 05 ). A better nerve score was obtained in the Group B. Conclusion BDNF can enhance the survival rate of the transplanted stem cells and induce their differentiation into neurons under hypothermia.

Objective To establish the electric controlled cortical impact (eCCI)-induced traumatic brain injury (TBI) model in rats with different severity in degree,which may serve as a suitable platform to provide experimental evidence for the pathophysiological following TBI.Methods A total of 40 male Wistar rats were randomly divided into 3 experimental groups and sham group.TBI rats (n=10/group) were positioned beneath the controlled cortical impactor device (eCCI) and subjected to impact injury at 2 mm depth of penetration,for a sustained depression of 200 ms,at 4 m/s,5 m/s,6 m/s velocity for mild,moderate,and severe TBI,respectively.Sham-operated rats (n=10) underwent identical surgical procedures,including craniotomy,without receiving the cortical impact.Neurological function and regional cerebral flow (24 h after CCI),contusion volume,histopathological,and ultrastructural changes (48 h after CCI) were measured,respectively.Results The severity of the pathological changes in rats was increased as the injury aggravated.The eCCI device impacted the brain at 4 m/s,5 m/s,6 m/s velocity for mild,moderate,and severe TBI,respectively.TBI groups showed impaired neurological function,and decreased rCBF lower than that of sham-operated group (all P＜0.01).Furthermore,neuronal pathological abnormalities in TBI groups,including neuron shrinking,perineuronal vacuole,and structural abnormalities of mitochondria.Increased severity of injury was apparent following the increased level of the impacted velocity,and significant differences were observed between TBI groups (P＜0.05).Conclusion The TBI animal model with mild,moderate,and severe brain injury can be established successfully by 4 m/s,5 m/s,and 6 m/s of impact velocity respectively with the eCCI-6.3 device.The novel eCCI-induced TBI model in rats possibly serves as a novel useful approach in the development of TBI models.

ObjectiveTo investigate the roles of 11 β-hydroxysteroid dehydrogenase type 1 ( 11 β-HSD1 )on hippocampus of rat with chronic unpredictable mild stress (CUMS).MethodsTwenty-four male SpragueDawley rats were randomly divided into control group and depressive model group. Chronic unpredictable mild stress (CUMS) was used to make up depressive animal model.Behavioral changes were recorded by body weight measuring,sucrose consumption test (SCT) and open field test (OFT),respectively.The mRNA transcription of 11β-HSD1 in hippocampus tissues of the rats were detected by real-time RT-PCR,and the protein expression of 11β-HSD1 were detected by western blot and immunofluorescence.ResultsBcforc starting CUMS protocol,the rats exhibited equivalent weight and sucrose consumption.Twenty-eight days after CUMS protocol,behavior parameters such as body weight,sucrose consumption,nunber of crossing,and number of rearing were significantly decreased in rats exposed to CUMS group compared with control group (P ＜ 0.05,P ＜ 0.01 ).Correspondingly,realtime RT-PCR assays showed the mRNA expression of 11 β-HSD1 in the hippocampus of CUMS group,which was (31 ±9) ％ lower than that of control group.Meanwhile,the protein expression of it in CUMS group was lower than that of control group (P ＜ 0.05 ).Inmunofluorescence revealed that the number of positive 11 3-HSD1 cells was high (223 ± 13) in the control group,while the number was decreased prominently (92 ± 11 ) in the CUMS group (P ＜ 0.01 ).ConclusionDepressive behavior of rats is induced and the expression of 11 β-HSD1 in the hippocampus is decreased prominently by CUMS,the mechanism of which is at least related to the low expression of 11β-HSD1 and disturbance of glucocorticoid metabolism caused by CUMS.

ObjectiveTo investigate the dynamic changes in microvascular ultrastructure in the cortex after the acute cerebral ischemia-reperfusion.Methods40 male rats were randomly divided into two groups（n=20 for sham operation group and cerebral ischemia-reperfusion group）. Cerebral ischemia-reperfusion model was produced using suture middle cerebral artery occlusion. Rats were sacrificed and the brain samples were adopted 1,3,12,72 h after ischemia-reperfusion, methyl methacrylate composite brain microvascular casting. The production of brain microvascular specimens, scanning electron microscopy of normal rat cerebral cortex microvessels and cerebral cortex of acute brain injury morphological changes in microvascular.ResultsCompared with the sham-operated group, cerebral ischemia-reperfusion in the cortex after the signs of vascular damage, then, vascular casting was to "bean" shape or even had a completely broken "tears candles" stump-like vascular casting, finally, to further the formation of a vascular zone cortex. ConclusionThe structural changes of brain microvascular in the cortex after acute cerebral ischemia-reperfusion is an important cause of cerebral microcirculation in rats.

Objective To screen altered proteins of hippocampus in the stress-induced depression (STRID) rat model, and explore the potential molecular mechanism. Methods Twenty Sprague-Dawley rats were randomly divided into the control group and STRID group, 10 rats in each group. Chronic unpredictable mild stress (CUMS) methods including fasting for solids and liquids, electric foot-shock, reversing day and night, cold water swimming, cage tilt, scare stimulation and tail pinch were conducted on STRID rats with no repeats for 28 days to make up the depression animal model. The control group was normally fed during this period. After the stress stimulation, the hippocampus protein samples were used for two dimensional electrophoresis to screen the differentially expressed protein, and then mass spectrum identification and function analyze were conducted. Results Compared with the control group, 34 proteins were altered in STRID group. Among which, 18 were up-regulated, and 16 were down-regulated. The differentially expressed proteins mainly located in cytoplasm, mitochondrion, extracellular exosome and myelin sheath. The involved signaling pathways included metabolic pathway, oxidative phosphorylation pathway, and Alzheimer's disease, Parkinson's disease and Huntington's disease pathways. Conclusion The altered proteins and dysfunction of nerve signaling, and the excess of oxidative phosphorylation in hippocampus of STRID rats may be one of the pathogenesises.

Intracranial infection is a common and serious complication of acute severe traumatic brain injury, with high mortality and disability rates, which significantly affects the prognosis. In recent years, with the widespread use of antibiotics, antibiotic-resistance rates of pathogens have risen year by year, and the choice of sensitive antibiotics is less and less, sometimes even in difficulties of no drugs available. This paper reviewed the treatment process of 1 case with intracranial infection caused by multi drug-resistant Klebsiella pneumonia after severe traumatic brain injury . The aim is to summarize the clinical experience.

Objective To study the effects of different concentrations of hypertonic saline (HS) and 20%mannitol on decreasing intracranial pressure (ICP) in patients with moderate-sever traumatic brain injury (TBI). Methods A total of 60 patients were randomly assigned into 7.5%HS group, 3%HS group and 20%mannitol group, 20 patients in each group. All of patients were treated with conventional treatment according to the diagnostic and treatment practices of TBI. When ICP was above 20 mmHg for more than 5 minutes, patients were administered corresponding hypertonic dehydrator. The levels of ICP, mean arterial pressure (MAP), cerebral perfusion pressure (CPP), urine volume per hour and serum sodium were monitored continuously within 6 hours after the initiation of therapy. Results All agents could significantly decrease the ICP (P<0.05), but the onset time in 7.5%HS group was less than that of the other two groups (P<0.05), and the decreased magnitude of ICP and the effective time of decreasing ICP in 7.5%HS group were more than those of the other two groups (P < 0.05). Both 7.5%HS and 3%HS could increase MAP and CPP. There was no statistical difference in serum sodium between both groups , but the diuretic effect in both groups was worse than that of 20%mannitol group. Conclusion The rapidly infusion of 7.5%HS could significantly decrease the ICP, increase the MAP and CPP without obvious side-effect in patients with moderate-sever TBI, and which is a safe and effective therapy for intracranial hypertension after traumatic brain injury .

Objective To investigate the effect of the overexpression of NeuroD1 on mediating transdifferentiation of spinal reactive astrocytes into neurons. Methods Spinal cord astrocytes were cultured from the SD rat, and reactive astrocytes were prepared by scratches treatment. Cells were divided into blank groups (NV group), control virus group (GFP group) and NeuroD1 virus group (NeuroD1 group). At 7 d after scratches treatment, GFP and NeuroD1 groups were infected with retroviruses carrying the GFP gene and and GFP gene plus NeuroD1 gene, respectively,whereas NV group was not infected with the virus. Twenty-four hours late, the culture medium were replaced by neuron conditioned medi?um. Cell morphology was examined at 1, 2, 3, 5, 7 and 14 d. DCX positive and NeuN positive cells were detected at 7 d and 14 d after infection by using immunofluorescence staining method, respectively. Results After replacement with the neuron conditioned medium, the nucleus was obviously plump, the cytoplasm was thin and neurites was reduced and ex?tended. Compared with the NeuroD1 group, neurites of NV group and GFP group were shorter with many branches and the nucleus was smaller. At 7 d after infection, cell morphology of NV group and GFP group gradually recovered, but cell morphology of NeuroD1 group did not. Compared with NV group and GFP group, NeuroD1 group had more DCX(9.84 ± 2.06%)and NeuN(8.25±2.78%)positive cells [F values 40.107 for DCX and 21.73 for NeuN (P<0.05)]. Conclusion The overexpression of NeuroD1 can mediate the transdifferentiation of spinal reactive astrocytes into neurons.

Objective To estimate whether the ligation of bilateral internal carotid artery in combination with one vertebral artery can lead to chronic cerebral hypoperfusion. Methods The sham operation, 2?VO and 3?VO rat models were subjected to the matching operation. Four weeks after operation,the cortical blood flow was determined. The learning and memory abilities were measured with Morris water maze test eight weeks later,then the rats were sacrificed to observe the morphological change of hippocampal CA1 region. Results Compared with the sham operation group((47±8.797)ml·min-1·100 g-1),the cerebral blood flow of 2?VO((24.30±8.999)ml ·min-1·100 g-1) and 3?VO((9.870±2.208)ml·min-1·100 g-1) were significantly decreased (P<0.01). Compared with the sham operation group((8.33±4.88)s),escape latencies of Morris water maze of 2?VO group ((14.78±7.84)s) and 3?VO group((14.86±7.96)s) in the fifth days also presented significantly increased (P<0.01),but rare difference between the two groups. Compared with the sham operation group[ (37.20±9.21) s, (10.01.±2.91)times],the target quadrant swimming time and crossing times of 2?VO group((20.13±5.80)s, (6.60±3.19)times) and 3?VO group((20.05±5.76)s,(6.55±2.59)times) in the fifth days also presented signifi?cantly decreased (P<0.01). There were distinct pathomorphology changes in hippocampal CA1 region of the two groups. Conclusion The ligation of bilateral internal carotid artery in combination with one vertebral artery can lead to chronic cerebral hypoperfusion,and can make the similar ethology representation with the 2?VO models.

Objective To investigate the signaling pathway and the key signal molecules of protein kinase (RIPK)3 in SH-SY5Y cells. Methods SH-SY5Y cells were transfected with RIPK3 expression plasmid vector to upregulate intracellular RIPK3, while the SH-SY5Y cells were transfected with empty vector plasmid, which was considered as control group. Western blot assay was used to check the expression of exogenous RIPK3 in cells. The proliferation rate of SH-SY5Y cells was determined by MTT assay at designated time to detect exogenous RIPK3 activity. Whole transcriptome sequencing (RNAseq) was used to detect the transcription of genes. Whole-transcriptomic gene transcription was measured by following Ingenuity Pathway Analysis (IPA) to obtain downstream signaling pathways and the key molecule, which were partly confirmed by following droplet digital PCR (ddPCR). Results Exogenous RIPK3 showed biological activity in SH-SY5Y, which inhibited the proliferation of cells. IPA showed that znic finger protein 36 (ZFP36) was significantly up-regulated as compared with that of the control group. The tran?scription levels of ZFP36 downstream genes such as tumor necrosis factor (TNF), brain derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF) and mRNA-decapping enzyme 2 (DCP2) were affected at the same time. Conclusion Within the limitations of this study, it seems that RIPK3 is notable for the development, inflammation and tumorigenesis of the nervous system as an independent regulator of ZFP36 gene and downstream effectors.