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51.
Telomere maintenance has emerged as an important molecular feature with impacts on adult glioma susceptibility and prognosis. Whether longer or shorter leukocyte telomere length (LTL) is associated with glioma risk remains elusive and is often confounded by the effects of age and patient treatment. We sought to determine if genotypically-estimated LTL is associated with glioma risk and if inherited single nucleotide polymorphisms (SNPs) that are associated with LTL are glioma risk factors. Using a Mendelian randomization approach, we assessed differences in genotypically-estimated relative LTL in two independent glioma case-control datasets from the UCSF Adult Glioma Study (652 patients and 3735 controls) and The Cancer Genome Atlas (478 non-overlapping patients and 2559 controls). LTL estimates were based on a weighted linear combination of subject genotype at eight SNPs, previously associated with LTL in the ENGAGE Consortium Telomere Project. Mean estimated LTL was 31bp (5.7%) longer in glioma patients than controls in discovery analyses (P = 7.82×10-8) and 27bp (5.0%) longer in glioma patients than controls in replication analyses (1.48×10-3). Glioma risk increased monotonically with each increasing septile of LTL (O.R.=1.12; P = 3.83×10-12). Four LTL-associated SNPs were significantly associated with glioma risk in pooled analyses, including those in the telomerase component genes TERC (O.R.=1.14; 95% C.I.=1.03-1.28) and TERT (O.R.=1.39; 95% C.I.=1.27-1.52), and those in the CST complex genes OBFC1 (O.R.=1.18; 95% C.I.=1.05-1.33) and CTC1 (O.R.=1.14; 95% C.I.=1.02-1.28). Future work is needed to characterize the role of the CST complex in gliomagenesis and further elucidate the complex balance between ageing, telomere length, and molecular carcinogenesis.  相似文献   
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The high incidence of opportunistic pulmonary infections in fludarabine-treated patients at Walter Reed Army Medical Center (WRAMC) and in the literature are described. A CancerLlt search of fludarabine from June 1983-April 1994 with subsequent cross referencing and a retrospective review of all patients receiving fludarabine at WRAMC was performed. A total of 2,269 patients with low-grade lymphoid malignancies who received 7,547 + cycles of fludarabine were identified from the literature. Seventy-three (3.2%) of these patients developed opportunistic infections. Seventy-one (97%) of these infections occurred in patients who were pretreated with alkylator regimens or corticosteroids. Forty-five (2%) of these were of respiratory origin and associated with a 56% mortality rate. In contrast, 6 of the 21 patients (29%) treated with fludarabine at WRAMC developed opportunistic pulmonary infections which included three Pneumocystis carinii (PCP), one PCP/disseminated Candidiasis, one Mycobacterium avium intracellulare, and one Aspergillus niger pneumonia. These infections developed during and after treatment with fludarabine in alkylator-resistant patients who had received corticosteroids before (n = 6), during (n = 1), or after (n = 4) fludarabine therapy. Lack of PCP prophylaxis was the only significant (P = .018) variable that differentiated patients who developed opportunistic pulmonary infections. Corticosteroid treatment before, during, or after fludarabine treatment in patients with alkylator-resistant, low-grade lymphoid malignancies who have not received PCP prophylaxis is associated with an increased risk of opportunistic pulmonary infections. Aggressive work-up of pulmonary syndromes and PCP prophylaxis in these patients should be considered during and after treatment with fludarabine. © 1995 Wiley-Liss, Inc.  相似文献   
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Summary In 43 pediatric patients (29 male, 14 female) with primary astrocytic tumors of the central nervous system (CNS), the correlation was evaluated between outcome and proliferative potential, measured by the bromodeoxyuridine (BrdU) labeling index (LI). Twenty-five patients had low-grade gliomas, 13 had anaplastic gliomas, and 5 had glioblastomas multiforme (GBM). All patients underwent surgery; 37 also had chemotherapy, radiation therapy, or both. The median BrdU LIs were < 1% (range 0–9.3%) in low-grade gliomas, 2.3% (range 0–21.2%) in anaplastic gliomas, and 7.7% (range 0–21.3%) in GBM. Seven of eight patients with BrdU LI > 5% have died (median survival 29 weeks). Median survival has not been reached in patients with BrdU LI <1% (19/22 alive) or between 1% and 5% (12/13 alive) after median follow-up periods of 165 and 120 weeks, respectively. A high BrdU LI correlated with short survival (p = 0.0001); the association between malignant histology and short survival was weaker (p = 0.019). BrdU LI is therefore a significant predictor of outcome in patients with primary CNS astrocytomas and appears to be a stronger predictor than histology in patients with low-grade and anaplastic gliomas. More patients need to be studied to confirm these preliminary observations. Address for offprints: M.D. Prados, Department of Neurological Surgery, c/o The Editorial Office, 1360 Ninth Avenue, Suite 210, San Francisco, CA 94122, USA  相似文献   
56.
Brachytherapy of brain tumors.   总被引:1,自引:0,他引:1  
Temporary implants of high-activity 125iodine sources have been used in the treatment of brain tumors since December 1979 at the University of California, San Francisco. For previously untreated patients who underwent external beam radiation therapy followed by implant boost, median survival from the date of diagnosis was 88 weeks for 34 patients with glioblastoma multiforme (GM) and 157 weeks for 29 patients with nonglioblastoma gliomas (NGM). For recurrent tumors treated with brachytherapy only, median survival from the date of the implant was 54 weeks for 45 patients with GM and 81 weeks for 50 patients with NGM. Finally, in 48 patients with recurrent tumors treated with combined hyperthermia and brachytherapy, median survival from the date of the implant was 46 weeks for 25 patients with GM and 44 weeks for 7 patients with metastases; 18-month survival was 65% for 16 patients with NGM. Brachytherapy appears to be a useful technique for the treatment of selected recurrent brain tumors and selected primary glioblastomas.  相似文献   
57.
Hemodynamic factors acting as modelator agents in the outflow region of great vessels and aortic arches have been studied by many authors. In our study, we have tried to analyse the influence which a modification of some of these factors, as it is an increased blood volume, could cause on truncus and aortic arches, by means of the perfusion of blood from chick embryos of 12-15 days of incubation to receptor embryos between stages 22-29 of HH. We have obtained a malformation percentage smaller than expected, on the basis of bibliographic data, so we now believe that hemodynamic factors, by themselves, don't play a role in the definitive morphogenesis and septation of great vessels and its main branches as important as believed until present time.  相似文献   
58.
In population-based glioma patients, we examined survival in relation to potentially pertinent constitutive polymorphisms, serologic factors, and tumor genetic and protein alterations in epidermal growth factor receptor (EGFR), MDM2, and TP53. Subjects were newly diagnosed adults residing in the San Francisco Bay Surveillance Epidemiology and End Results Area during 1991 to 1994 and 1997 to 1999 with central neuropathology review (n = 873). Subjects provided blood for serologic studies of IgE and IgG to four herpes viruses and constitutive specimens for genotyping 22 polymorphisms in 13 genes (n = 471). We obtained 595 of 697 astrocytic tumors for marker studies. We determined treatments, vital status, and other factors using registry, interview, medical record, and active follow-up data. Cox regressions for survival were adjusted for age, gender, ethnicity, study series, resection versus biopsy only, radiation, and chemotherapy. Using a stringent P < 0.001, glioma survival was associated with ERCC1 C8092A [hazard ratio (HR), 0.72; 95% confidence limits (95% CL), 0.60-0.86; P = 0.0004] and GSTT1 deletion (HR, 1.64; 95% CL, 1.25-2.16; P = 0.0004); glioblastoma patients with elevated IgE had 9 months longer survival than those with normal or borderline IgE levels (HR, 0.62; 95% CL, 0.47-0.82; P = 0.0007), and EGFR expression in anaplastic astrocytoma was associated with nearly 3-fold poorer survival (HR, 2.97; 95% CL, 1.70-5.19; P = 0.0001). Based on our and others' findings, we recommend further studies to (a) understand relationships of elevated IgE levels and other immunologic factors with improved glioblastoma survival potentially relevant to immunologic therapies and (b) determine which inherited ERCC1 variants or other variants in the 19q13.3 region influence survival. We also suggest that tumor EGFR expression be incorporated into clinical evaluation of anaplastic astrocytoma patients.  相似文献   
59.
PURPOSE: This Phase II study was designed to determine the median survival time of adults with supratentorial glioblastoma treated with a combination of temozolomide (TMZ) and 13-cis-retinoic acid (cRA) given daily with conventional radiation therapy (XRT). METHODS AND MATERIALS: This was a single arm, open-labeled, Phase II study. Patients were treated with XRT in conjunction with cRA and TMZ. Both drugs were administered starting on Day 1 of XRT, and chemotherapy cycles continued after the completion of XRT to a maximum of 1 year. RESULTS: Sixty-one patients were enrolled in the study. Time to progression was known for 55 patients and 6 were censored. The estimated 6-month progression-free survival was 38% and the estimated 1-year progression-free survival was 15%. Median time to progression was estimated as 21 weeks. The estimated 1-year survival was 57%. The median survival was 57 weeks. CONCLUSIONS: The combined therapy was relatively well tolerated, but there was no survival advantage compared with historical studies using XRT either with adjuvant nitrosourea chemotherapy, with TMZ alone, or with the combination of TMZ and thalidomide. Based on this study, cRA does not seem to add a significant synergistic effect to TMZ and XRT.  相似文献   
60.
Purpose: Loss of PTEN, which is common in glioblastoma multiforme (GBM), results in activation of the mammalian target of rapapmycin (mTOR), thereby increasing mRNA translation of a number of key proteins required for cell-cycle progression. CCI-779 is an inhibitor of mTOR. The primary objectives of this study were to determine the efficacy of CCI-779 in patients with recurrent GBM and to further assess the toxicity of the drug. Experimental Design: CCI-779 was administered weekly at a dose of 250 mg intravenously for patients on enzyme-inducing anti-epileptic drugs (EIAEDs). Patients not on EIAEDs were initially treated at 250 mg; however, the dose was reduced to 170 mg because of intolerable side effects. Treatment was continued until unacceptable toxicity, tumor progression, or patient withdrawal. The primary endpoint was 6-month progression-free survival. Results: Forty-three patients were enrolled; 29 were not on EIAEDs. The expected toxicity profile of increased lipids, lymphopenia, and stomatitis was seen. There were no grade IV hematological toxicities and no toxic deaths. One patient was progression free at 6 months. Of the patients assessable for response, there were 2 partial responses and 20 with stabilization of disease. The median time to progression was 9 weeks. Conclusions: CCI-779 was well tolerated at this dose schedule; however, there was no evidence of efficacy in patients with recurrent GBM. Despite initial disease stabilization in approximately 50% of patients, the durability of response was short. Because of the low toxicity profile, CCI-779 may merit exploration in combination with other modalities.  相似文献   
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