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61.
According to the recently updated World Health Organization (WHO) classification (2016), grade II–III astrocytomas are divided into IDH-wildtype and IDH-mutant groups, the latter being significantly less aggressive in terms of both progression-free and total survival. We identified a small cohort of WHO grade II–III astrocytomas that harbored the IDH1 R132H mutation, as confirmed by both immunohistochemistry and molecular sequence analysis, which nonetheless had unexpectedly rapid recurrence and subsequent progression to glioblastoma. Among these four cases, the mean time to recurrence as glioblastoma was only 16 months and the mean total survival among the three patients who have died during the follow-up was only 31 months. We hypothesized that these tumors had other, unfavorable genetic or epigenetic alterations that negated the favorable effect of the IDH mutation. We applied genome-wide profiling with a methylation array (Illumina Infinium Human Methylation 450k) to screen for genetic and epigenetic alterations in these tumors. As expected, the methylation profiles of all four tumors were found to match most closely with IDH-mutant astrocytomas. Compared with a control group of four indolent, age-similar WHO grade II–III astrocytomas, the tumors showed markedly increased levels of overall copy number changes, but no consistent specific genetic alterations were seen across all of the tumors. While most IDH-mutant WHO grade II–III astrocytomas are relatively indolent, a subset may rapidly recur and progress to glioblastoma. The precise underlying cause of the increased aggressiveness in these gliomas remains unknown, although it may be associated with increased genomic instability.  相似文献   
62.
4-Hydroperoxycyclophosphamide (4-HC), a commonly used marrow-purging agent, is active against many tumors, but is also toxic to normal marrow progenitors. Amifostine (WR-2721) is a sulfhydryl compound with chemoprotectant activity. Preclinical studies using suspensions of bone marrow and breast cancer cells demonstrated that ex vivo treatment with amifostine followed by 4-HC resulted in protection of marrow progenitors, with no compromise in the antitumor effect of 4-HC. This fact stimulated the development of a clinical trial. Bone marrow was harvested from 15 poor-prognosis breast cancer patients and randomly assigned to ex vivo treatment with amifostine followed by 4-HC (amifostine + 4-HC), or treatment with 4-HC alone. High-dose chemotherapy was then administered followed by infusion of the purged autologous bone marrow support (ABMS). Leukocyte engraftment, defined as a white blood cell count > or = 1 x 10(9)/L, was achieved in an average of 26 days for patients whose marrow was purged with amifostine + 4-HC versus 36 days for patients whose marrow was purged with 4-HC alone (P = .032). The average number of platelet transfusions (12 v 29; P = .017) and days of antibiotic therapy (28 v 40; P = .012) were significantly less for patients whose marrow was exposed to amifostine + 4-HC, compared with 4-HC alone. Unpurged backup marrow fractions were infused into three patients whose marrow was purged with 4-HC alone, because of inadequate marrow recovery. None of the patients who received amifostine + 4-HC-purged marrow required a backup marrow fraction. Complete remissions were achieved in 83% of patients with measurable disease, with no difference between the two cohorts. Forty- three percent of patients remained alive and progression-free at a mean of 13 months posttransplant. There was no significant difference in the rate or pattern of relapse for patients whose marrow was purged with amifostine + 4-HC compared with those whose marrow was purged with 4-HC alone. Ex vivo treatment of marrow with amifostine significantly shortens the time to marrow recovery, thereby reducing the risk of myelosuppressive complications in breast cancer patients receiving high- dose chemotherapy and 4-HC-purged ABMS. Since supportive care requirements are also significantly decreased, amifostine may reduce the cost of such therapy.  相似文献   
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64.
Patients with a diffuse glioma may experience cognitive decline or improvement upon resective surgery. To examine the impact of glioma location, cognitive alteration after glioma surgery was quantified and related to voxel‐based resection probability maps. A total of 59 consecutive patients (range 18–67 years of age) who had resective surgery between 2006 and 2011 for a supratentorial nonenhancing diffuse glioma (grade I–III, WHO 2007) were included in this observational cohort study. Standardized neuropsychological examination and MRI were obtained before and after surgery. Intraoperative stimulation mapping guided resections towards neurological functions (language, sensorimotor function, and visual fields). Maps of resected regions were constructed in standard space. These resection cavity maps were compared between patients with and without new cognitive deficits (z‐score difference >1.5 SD between baseline and one year after resection), using a voxel‐wise randomization test and calculation of false discovery rates. Brain regions significantly associated with cognitive decline were classified in standard cortical and subcortical anatomy. Cognitive improvement in any domain occurred in 10 (17%) patients, cognitive decline in any domain in 25 (42%), and decline in more than one domain in 10 (17%). The most frequently affected subdomains were attention in 10 (17%) patients and information processing speed in 9 (15%). Resection regions associated with decline in more than one domain were predominantly located in the right hemisphere. For attention decline, no specific region could be identified. For decline in information speed, several regions were found, including the frontal pole and the corpus callosum. Cognitive decline after resective surgery of diffuse glioma is prevalent, in particular, in patients with a tumor located in the right hemisphere without cognitive function mapping.  相似文献   
65.

Objectives  

The primary aim of this study is to perform an internal quality control of pediatric brain tumor surgery in the neurosurgical department of the VU University Medical Center Amsterdam (The Netherlands). Secondly, this study aims to contribute to the accumulating data concerning outcome in pediatric neurosurgery, in order to establish institutional practice benchmarks.  相似文献   
66.
Vandertop WP  Lagerwaard FJ 《The New England journal of medicine》2006,355(22):2375; author reply 2375-2375; author reply 2376
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67.
68.
Summary  The authors report the case of a 29-year-old female who presented with symptoms of shunt dysfunction 11 years after first being shunted for an aqueductal stenosis. After numerous revisions she developed an isolated third ventricle, necessitating triventricular shunting to obtain a new equilibrium. An isolated third ventricle is a very rare phenomenon, usually seen in very complex hydrocephalus and only reported on twice before (Filler et al., 1995). Etiological factors postulated in the development of an isolated lateral or fourth ventricle, all seem to contribute also to the development of an isolated third ventricle.  相似文献   
69.
Aim of the studyTumour angiogenesis and invasion are key features of glioblastoma multiforme (GBM). Angiogenesis inhibitors increase progression-free survival (PFS) of recurrent GBM patients. VEGF inhibition controls the bulk tumour growth by inhibition of angiogenesis, but does not inhibit the invasive tumour component. We investigated if invasive tumour growth can be controlled by combining anti-VEGF treatment with irradiation of tumour plus surrounding brain in an orthotopic murine model for GBM.Methods and materialsGBM cell line U251-NG2 was inoculated through a guide screw in the right frontal lobe of 53 athymic nude mice. Pegaptanib (a slow-releasing aptamer against VEGF) was injected in the tumour bed either or not followed by irradiation treatment with implanted I-125 seeds. Pegaptanib and/or irradiation were compared with sham-treated controls, resulting in four groups of 10–15 mice each. After 6 weeks of treatment, histological analysis was performed on all brains.ResultsVEGF inhibition by locally deposited pegaptanib decreased tumour blood vessel density, and increased tumour hypoxia. Pegaptanib treatment still allowed the formation of tumour satellites. Irradiation decreased tumour size and suppressed formation of satellites. Combined pegaptanib plus irradiation further increased PFS. Tumour size directly correlated with PFS.Concluding statementThe anti-tumour effects of local VEGF inhibition are partially circumvented by the formation of invasive tumour satellites. Additional irradiation is effective in slowing down proliferation of these invasive tumour components.  相似文献   
70.
Inthispaper ,wereportedriskfactorsassociatedwithHIVinfectionamongwomenandtheirimplicationsforAIDSpreventioneffortsintheDodomaregion ,Tanzania .1 SUBJECTSANDMETHODS1.1 Thepopulationandsampleselection ThestudywasconductedintheDodomaregion ,whichhasanestimate…  相似文献   
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