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Anti-sense oligonucleotide of p21(waf1/cip1) prevents interleukin 4-mediated elevation of p27(kip1) in low grade astrocytoma cells 总被引:4,自引:0,他引:4
Liu J Estes ML Drazba JA Liu H Prayson R Kondo S Jacobs BS Barnett GH Barna BP 《Oncogene》2000,19(5):661-669
Elevation of the cyclin-dependent kinase (cdk) inhibitor, p27(kip1) is necessary for Interleukin (IL)-4-mediated growth arrest of human low grade astrocytoma (RTLGA) cells and occurs at 24 h of treatment. Pathways involved in IL4 alteration of p27(kip1) are unknown, however. Here we investigated whether other cdk inhibitors contributed to the actions of IL-4 on RTLGA cells. By 12 h of IL-4 treatment, both cdk4 and cdk2 kinase activities against the retinoblastoma protein (pRb) were reduced and nuclear entry of pRb was prohibited. Twelve-hour cdk complexes contained elevated p21(waf1/cip1) but not p27(kip1), p15(ink4B) or p16(ink4A). IL-4 increased p21(waf1/cip1) but not p27(kip1) mRNA levels, and stimulated luciferase activity of a p21(waf1/cip1) promoter-luciferase reporter. In p53-mutant WITG3 cells, IL-4 did not alter p21(waf1/cip1) mRNA and promoter-luciferase activity or p27(kipl) protein, suggesting a need for functional p53. STAT6 phosphorylation by IL-4, however, occurred in both p53-mutant WITG3 and p53-functional RTLGA cells. Pre-treatment of RTLGA with anti-sense but not missense p21(waf1/cip1) oligonucleotide prior to IL-4: (a) restored cdk activities; (b) reduced cdk4-associated p21(waf1/cip1) levels; (c) prevented p27(kipl) elevation; and (d) reversed growth arrest. These results are the first to suggest that p21(waf1/cip1) is essential for IL-4-mediated elevation of p27(kip) and growth arrest of astrocytoma cells. 相似文献
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Harold H. Morris Melinda L. Estes Robin Gilmore Paul C. Van Ness Gene H. Barnett John Turnbull 《Epilepsia》1993,34(6):1038-1043
We identified 39 patients with chronic epilepsy (seizures ≥2 years) proven to have primary brain tumors. These cases represent ~12% of the surgery cases for epilepsy in the same period. Mean age of seizure onset was 13.2 years: mean duration before operation was 10.5 years. Thirty-eight of 39 had normal neurologic examination. Twenty-six tumors were temporal, 7 were frontal, 4 were parietal, and 2 were occipital. Nine of 26 (34.6%) of the temporal group had contralateral interictal EEG spikes. Pathology was 15 ganglioglioma, 13 low-grade astrocytoma, 4 oligodendroglioma, 2 low-grade mixed glioma, 1 pleomorphic xanthoastrocytoma, 2 dysembryoplastic neuroepithelial tumor, and 1 ependymoma. Postoperative seizure frequency (minimum follow-up 6 months) ranged from 15 to 16 seizure-free or auras only in patients with temporal tumors and total gross tumor removal (mean follow-up 28 months) to 0 of 6 seizure-free in patients with extratemporal tumors who underwent subtotal resections or biopsy. 相似文献
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BACKGROUND: In surgical treatment of morbid obesity, maintaining a restrictive anastomosis is key to long-range success. However, laparoscopic Roux-en-Y gastric bypass (LRYGB) may result in gastrojejunal (GJ) stricture, requiring treatment in up to 27% of patients. METHODS: This is a retrospective review of the outcome of 223 consecutive LRYGB patients. Patients developing stricture received standard endoscopic balloon dilation by the same surgeon. Stricture and nonstricture groups were compared for excess body weight loss (EBWL) at 1, 3, 6, and 12 months. RESULTS: GJ stricture requiring dilation occurred in 38 patients (17%). After dilation all patients were relieved of stricture symptoms and none required revision. By 12 months, patients with stricture had an EBWL of 86% compared with nonstrictured patients at 75%. CONCLUSION: Endoscopic balloon dilation is a safe and effective treatment option for GJ stricture. Improved weight loss occurred for patients with stricture requiring dilation. 相似文献