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PURPOSE: To assess the antitumor efficacy of pharmacokinetically guided topotecan dosing in previously untreated patients with medulloblastoma and supratentorial primitive neuroectodermal tumors, and to evaluate plasma and CSF disposition of topotecan in these patients. PATIENTS AND METHODS: After maximal surgical resection, 44 children with previously untreated high-risk medulloblastoma were enrolled, of which 36 were assessable for response. The topotecan window consisted of two cycles, administered initially as a 30-minute infusion daily for 5 days, lasting 6 weeks. Pharmacokinetic studies were conducted on day 1 to attain a topotecan lactone area under the plasma concentration-time curve (AUC) of 120 to 160 ng/mL.h. After 10 patients were enrolled, the infusion was modified to 4 hours, with dosage individualization. RESULTS: Of 36 assessable patients, four patients (11.1%) had a complete response and six (16.6%) showed a partial response, and disease was stable in 17 patients (47.2%). Toxicity was mostly hematologic, with only one patient experiencing treatment delay. The target plasma AUC was achieved in 24 of 32 studies (75%) in the 30-minute infusion group, and in 58 of 93 studies (62%) in the 4-hour infusion group. The desired CSF topotecan exposure was achieved in seven of eight pharmacokinetic studies when the topotecan plasma AUC was within target range. CONCLUSION: Topotecan is an effective agent against pediatric medulloblastoma in patients who have received no therapy other than surgery. Pharmacokinetically guided dosing achieved the target plasma AUC in the majority of patients. This drug warrants testing as part of standard postradiation chemotherapeutic regimens. Furthermore, these results emphasize the importance of translational research in drug development, which in this case identified an effective drug.  相似文献   
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PURPOSE: To describe clinical features, therapeutic approaches, and prognostic factors in pediatric patients with atypical teratoid/rhabdoid tumors (ATRT) treated at St Jude Children's Research Hospital (SJCRH). PATIENTS AND METHODS: Primary tumor samples from patients diagnosed with ATRT at SJCRH between July 1984 and June 2003 were identified. Pathology review included histologic, immunohistochemical analysis, and fluorescence in situ hybridization for SMARCB1 (also known as hSNF5/INI1) deletion. Clinical records of patients with pathologic confirmation of ATRT were reviewed. RESULTS: Thirty-seven patients were diagnosed with ATRT at SJCRH during the 19-year study interval. Six patients were excluded from this clinical review based on pathologic or clinical criteria. Of the remaining 31 patients, 22 were younger than 3 years. Posterior fossa primary lesions and metastatic disease at diagnosis were more common in younger patients with ATRT. All patients underwent surgical resection; 30 received subsequent chemotherapy. The majority of patients aged 3 years or older received postoperative craniospinal radiation. Two-year event-free (EFS) and overall survival (OS) of children aged 3 years or older (EFS, 78% + 14%; OS, 89% +/- 11%) were significantly better than those for younger patients (EFS, 11% +/- 6%; OS, 17% +/- 8%); EFS, P = .009 and OS, P = .0001. No other clinical characteristics were predictive of survival. Three of four patients 3 years or older with progressive disease were successfully rescued with ifosfamide, carboplatin, and etoposide therapy. CONCLUSION: Children presenting with ATRT before the age of 3 years have a dismal prognosis. ATRT presenting in older patients can be cured using a combination of radiation and high-dose alkylating therapy. Older patients with relapsed ATRT can have salvage treatment using ICE chemotherapy.  相似文献   
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Autism spectrum disorder (ASD) is a neurodevelopmental disorder afflicting about one in every 68 children. It is behaviorally diagnosed based on a triad of symptoms, including impairment in communication, impairment in sociability and abnormal and stereotypic behavior. The subjectivity of behavioral diagnosis urges the need for clinical biomarker tests to improve and complement ASD diagnosis and treatment. Over the past two decades, researchers garnered a broad range of biomarkers associated with ASD and often correlating with the severity of ASD, which includes metabolic and genetic biomarkers or neuroimaging abnormalities. Metabolic biomarkers are either involved in key pathways such as a trans-sulfuration pathway or produced due to the derangement of these pathways in the case of oxidative stress. Recent studies reported several genetic abnormalities related to ASD, encompassing various mechanisms, from copy number variations (CNVs) and single nucleotide polymorphisms (SNPs) to chromosomal anomalies. However, it is still premature to consider these genetic variants as true biomarkers for ASD, due to their low reproducibility and regional-specific nature. Herein, we comprehensively review state of the art about major biomarkers reported in ASD and the association of some biomarkers with ASD symptoms and severity. It is important to establish those biomarkers to be able to help in the diagnosis and to optimize the treatment of ASD.  相似文献   
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The Interactive Whiteboard (IWB) is now a common technological artefact in Swedish preschools and schools. This study examines preschool teachers’ thinking behind the embedding of IWB in the early years’ mathematics classroom and how preschool teachers structure their mathematical activities when using IWB. Two complementary empirical studies, that is, interviews and video observations, were conducted with four preschool teachers. The findings demonstrate that (just) having a positive attitude to technological artefacts like IWB is less likely to enrich the learning environment and lead to pedagogical change. This suggests that teachers’ IWB use is mostly informed by their pedagogical knowledge.  相似文献   
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The scarring response after a penetrant central nervous system injury results from the interaction between invading leptominingeal/pericyte-derived fibroblasts and endogenous reactive astrocytes about the wound margin. Extracellular matrix and scar-derived axon growth inhibitory mole- cules fill the lesion site providing both a physical and chemical barrier to regenerating axons. Dec orin, a small leucine-rich chondroitin-dermatan sulphate proteoglycan expressed by neurons and astrocytes in the central nervous system, is both anti-fibrotic and anti-inflammatory and attenu- ates the formation and partial dissolution of established and chronic scars. Here, we discuss the potential of using Decorin to antagonise scarring in the central nervous system.  相似文献   
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The objective of the study is to provide information about non disease specified outcome measures which evaluate disability in patients who have impairments in hand and upper extremity and to find the extent to which they are evaluating “disability” based on ICF hand Core Set (activity limitation and participation restriction). MEDLINE, CINAHL, GOOGLE SCHOLAR , OVID and SCIENCE DIRECT databases were systematically searched for studies on non disease specified outcome measures used to evaluate upper extremity function; only studies written in English were considered. We reviewed titles and abstracts of the identified studies to determine whether the studies met predefined eligibility criteria (eg, non disease specified out come measures used in hand injured patients). All the outcome measures which had eligibility included. After full text review ,7 non disease specified outcome measures in hand were identified. Studies were extracted, and the information retrieved from them. All the outcome measures which had incuded, were linked with ICF hand core set disability part (activity and participation). All of them only linked to 16 (42 %) components of ICF hand Core Set, which were most activity and less participation from ICF. None of the non disease specified out come measures in hand injuries cover all domains of disability from the ICF Hand Core Set.  相似文献   
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