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Objective:To investigate the effect of miR-26a mediated phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT) signaling pathway on angiogenesis in rats with cerebral ischemia.Methods:A total of 100 male SD rats were divided into sham operation group, model group, miR-NC group, and miR-26a group according to the random number table method. The miR-NC group and the miR-26a group were injected with 5 μl miR-26a simulant negative control and miR-26a simulant into the lateral ventricle respectively. The sham operation group and the model group were injected with the same amount of normal saline respectively. The middle cerebral artery occlusion model was induced by the modified intraluminal suture method. In the sham operation group, the thread was only inserted without ligation. Five rats in each group were injected intraperitoneally with 5-bromodeoxyuridine (BrdU) daily for 7 days. Rat brain microvascular endothelial cells (BMECs) cultured and transfected in vitro were divided into control group, oxygen glucose deprivation (OGD) group, miR-NC group, and miR-26a group. The dual luciferase experiment verified the regulatory effect of miR-26a on the phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Longa score was used to detecte the neurological damage of rats. The volume of cerebral infarction was measured by triphenyltetrazolium chloride (TTC) staining. The methyl thiazolyl tetrazolium (MTT) staining, annexin Ⅴ fluorescein isothiocyanate/propidium iodide double staining and tubule formation experiment were used to detect the proliferation, apoptosis and angiogenesis of BMECs, respectively. Real-time fluorescence quantitative reverse transcription polymerase chain reaction was used to detect the miR-26a expression of ischemic brain tissue and BMECs. Immunofluorescence double labeling method (BrdU/von Willebrand factor [vWF]) was used to detect the proliferation of rat vascular endothelial cells. Western blot analysis was used to detect the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiopoietin-2 (Ang-2), PTEN, PI3K and Akt protein in ischemic brain tissue.Results:Bioinformatics and dual luciferase experiments verified the targeted regulation of PTEN by miR-26a. Compared with the sham operation group, the expression of miR-26a, VEGF, bFGF, Ang-2, PI3K, AKT and the number of BrdU + /VWF + cells in ischemic brain tissue in the model group and miR-NC group increased, while the expression of PTEN decreased (all P<0.05). Compared with the model group, the effect of various indexes in the miR-26a group was more significant (all P<0.05). Compared with the control group, the proliferation and angiogenesis of BMECs in the OGD group and the miR-NC group were significantly increased, and the apoptosis was significantly reduced (all P<0.05). Compared with the OGD group, the effect of various indexes in the miR-26a group was more significant (all P<0.05). Conclusion:miR-26a can mediate the targeted inhibition of PTEN expression, up-regulate angiogenesis related factors (VEGF, bFGF and Ang-2), and promote vascular endothelial cell proliferation and angiogenesis in rats with cerebral infarction by activating PI3K/Akt signaling pathway.
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Objective To evaluate percutaneous endoscopic gastrostomy (PEC) in long-term coma patients at different phases who received trans-nasal feeding in Department of Neurosurgery. Methods A total of 51 patients who received trans-nasal feeding because of long-term coma were randomly divided into 2 groups to undergo PEG at 25-39 days after coma (n =24) or at 40-60 days (n = 27) , respectively. The rates of upper gastrointestinal bleeding, average episodes of bleeding, average hemostatic time, the rates of aspiration and aspiration pneumonia were compared between the 2 groups. Results The rates of upper gastrointestinal bleeding, aspiration and aspiration pneumonia in post-PEG patients were significantly lower than those in pre-PEG patients (P < 0.05). Before the procedure of PEG, the rates of upper gastrointestinal hemorrhage,average episodes of bleeding, rates of aspiration and aspiration pneumonia in 25-39-day group were significantly lower than those in 40-60-day group (P < 0.05). There was no significant difference between 2 groups, in regarding of either hemostatic time, or rates of upper gastrointestinal bleeding, aspiration and aspiration pneumonia after PEG (P > 0. 05). Conclusion PEG may decrease the rates of upper gastrointestinal bleeding, aspiration and aspiration pneumonia in neurosurgical patients receiving trans-nasal feeding because of long-term coma. PEG is preferably performed on 25-39 days of onset to 40-60 days. If there is no contraindication, 25-39 days after coma is likely to be the optimal time for PEG.
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Objective To observe the effects of mild hypothermia on the dynamic change of neuron specific enolase (NES) in serum, the damaged neuron number around the impact site and the content of brain tissue water following traumatic brain injury (TBI) in rats so as to provide a quantitative parameters to evaluate the protective effect of the mild hypothermia on the brain. Methods A total of 45 SD rats were subjected to a lateral moderate cortical impact injury caused by a free-falling object and divided randomly into three groups:⑴ sham operation group (Group A);⑵ normothermic group (Group B);⑶ hypothermia group (Group C). The Group C was treated with mild hypothermia and the Group B with normothermia immediately after injury. A series of samples were obtained directly 3, 6 and 24 respectively after trauma in three groups. Pathomorphological method was used to observe the number of the damaged cortical neurons around the impact site. The serum concentration of NSE and the water content of brain tissue water were measured by radio-immunoassay. Results Following TBI in rats, the serum level of NSE was significantly increased (P
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Objective To investigate the effects of ?-aescin on nuclear factor-?B (NF-?B) activities and tumor necrosis factor-? (TNF-?) protein expression in the rat brain tissue following acute traumatic brain injury (TBI). Methods A total of 62 SD rats were subjected to a lateral cortical impact injury caused by a free-falling object and divided randomly into four groups, ie, sham operation group (Group A), injury group (Group B), ?-aescin treatment group (Group C) and pyrrolidine dithocarbamate (PDTC) treatment group (Group D). Group C was administered with ?-aescin and Group D treated with PDTC immediately after injury. A series of brain samples were obtained directly 6, 24 hours and three days respectively after operation in four groups. The NF-?B activation of rat brain was determined by electrophoretic mobility shift assay (EMSA) and the levels of TNF-? protein in rat brain measured by radio-immunoassay (RIA). In the meantime, the water content of rat brain was measured and pathomorphological observation carried out. Results Compared with Group A, NF-?B activities, the levels of TNF-? protein and the water content of the rat brain were significantly increased (P
