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Objective To investigate the role of ceramide pathway in cell proliferation and early apoptosis induction in U251 glioma cell after cannabinoid receptora agent anandmide(AEA)treatment.Methods U251 gliom cells were treated with AEA(1-10 μmol/L),Ceramide(5-20 μmol/L) and fumonisin B1 (FB1) (10 μmol/L) pretreatment.The growth inhibition rate of U251 was investigated by MTT assay.The early events of the apoptosis were measured by flow cytometry using annexin-V/propium iodide(PI) double staining method.Results Different concentrations of AEA inhibited the proliferation of human glioma U251 cells,and had synergistic effect with CM by FB1(10 μmol/L)pretreatment for 24 h.After exposure to AEA(10 μmol/L)for 24 h,U251 gliomacells could undergo the early cell apoptosis which was affected by FB1(10 μmol/L).Conclusion AEA through the CM de novo synthesis pathway,and CM concentration was lazy in collaboration,thus inhibiting human glioma U251 cell proliferation and induce early apoptosis.
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Objective To investigate the inhibitory effect of RNA interference on the expression of Aurora A in U251 cells, and the influence on proliferation and apoptosis of U251 cells. Methods The siRNA specific for Aurora A was synthesized and transfected into U251 cells in vitro. Aurora A mRNA expression and protein content were detected by RT-PCR and Western blotting respectively. The cell proliferation and apoptosis were observed by methyl thiazolyl tetrazolium(MTT) and flow cytometry(FCM). Transmission electron microscope was used to observe the ultrastructural changes of U251 cells. Results After transfection, the expression level of Aurora A mRNA was significantly decreased(P<0.01), and the protein content of Aurora A was also obviously reduced. The inhibitory rate of cell proliferation reached up to 67.57% 72 hours after transfection, which was significantly higer than that of normal control group(P<0.01). The apoptosis rate of U251 cells was significantly increased from (3.69±0.87)% to (15.34±2.16)% (P<0.01). Under the transmission electron microscope, it was observed that the U251 cells showed typical morphologic changes of apoptosis after transfection, such as karyopyknosis, chromatin condensation and margination, intracytoplasmic vacuoles formed, and apoptotic bodies formed. Conclusion The expression of Aurora A gene can be inhibited by siRNA successfully, and it results in the suppression of cell growth and induce apoptosis of human glioma cells in vitro. Aurora A may become a new target for the gene therapy of gliomas.
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Objective To study the role of transcranial Doppler (TCD) in early diagnosis of posttraumatic vasospasm in traumatic brain injury patients and in treatment effect monitoring of hyperxia liquid for this condition. Methods Seventy-four patients with posttraumatic vasospasm were divided into two groups. The control group (n=42) received the general treatment, while the treatment group (n=32) received the treatment of hyperxia liquid in addition to the general treatment. Their cerebral blood flow velocities of bilateral MCA and extra-cranial portion of ICA were monitored regularly by TCD, starting from the first day after head injury until 14th day. The changes of physiological and neurofunctional parameters in both groups were compared, including cerebral vasospasm(CVS),arterial blood oxygen pressure (PaO 2),arterial blood oxygen saturation (SaO 2), the Glasgow coma scale (GCS)and the ultimate effects of treatment as indicated by Glasgow outcome scale(GOS). Results Cerebral vasospasm occurred in 1 to 3 days and peaked to the 3 to 7 days after injury, then markedly relieved at 14 days after injury. After infusion of hyperxia liquid, the PaO 2 and SaO 2 in the treatment group were significantly higher than those of the control group. The degree of vasospasm was significantly higher in the control group than that in the treatment group. GCS and GOS of the treatment group were significantly higher than those of the control group. Poor outcome was common in patients with severe cerebral vasospasm. Conclusion Early posttraumatic vasospasm can be detected by TCD. High-oxygen liquid is effective for treating posttraumatic vasospasm.
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Purpose:To evaluate the significance of NF ?B P65 protein expression in various human cerebral tumors. Methods:The expression of NF ?B P65 protein in 106 cases of cerebral tumors was studied immunohistochemically. 106 cases included 64 cases of astrocytic tumors and 22 cases of medulloblastoma and 20 cases of meningioma. 10 cases of normal brain tissue were employed as a control group.Results:The positive rate of NF ?B P65 protein of 64 astrocytic tumor specimens was 54.7%; the positive rate of NF ?B P65 protein of 22 cases of medulloblastoma was 36.4% and 5.0% for 20 cases of meningioma. In contrast, none of the normal tissues exhibited NF ?B P65 protein staining. Significant difference were observed between astrocytic tumor group and meningioma, as well as between medulloblastoma and meningioma ( P
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Aim To study the mechanism of curcumin induced U251 cell apoptosis. Methods U251 cells were treated with 20～100?mol?L~ -1 curcumin for 24 h and the growth inhibition rates of U251 cells were measured with MTT method. MTT method was used to measure the caspase inhibitors effect on curcumin too. Cell apoptosis was inspected with flow cytometry (FCM) and observed using electron microscope. The protein levels of FAK in U251 cells were observed by SP immunocytochemistry. The activity of caspase-3 was measured by spectrofluorometry. Results Curcumin inhibited the proliferation of U251 cells,induced apoptosis of U251 cells. At the same time the protein levels of FAK in U251 cells decreased and the activity of caspase-3 increased significantly. The apoptosis of U251 cells was partially reversed by caspase inhibitors. Conclusion Curcumin induced apoptosis via inhibition of expression of FAK and activation of caspase-3.