Search results for "Brain Neoplasm"
showing 10 items of 249 documents
Preservation of glial cytoarchitecture from ex vivo human tumor and non-tumor cerebral cortical explants: A human model to study neurological diseases
2007
For the human brain, in vitro models that accurately represent what occurs in vivo are lacking. Organotypic models may be the closest parallel to human brain tissue outside of a live patient. However, this model has been limited primarily to rodent-derived tissue. We present an organotypic model to maintain intraoperatively collected human tumor and non-tumor explants ex vivo for a prolonged period of time (similar to 11 days) without any significant changes to the tissue cytoarchitecture as evidenced through immunohistochemistry and electron microscopy analyses. The ability to establish and reliably predict the cytoarchitectural changes that occur with time in an organotypic model of tumor…
Effects of laser-induced thermotherapy (LITT) on proliferation and apoptosis of glioma cells in rat brain transplantation tumors.
2002
Background and Objectives Laser-induced thermotherapy (LITT) is an approach to the treatment of brain tumors especially in poorly accessible regions. Its clinical applicability with tumor cell destruction has been shown in several studies. However, no data are known about specific effects on tumors cells due to LITT in the time course of the lesion. Study Design/Materials and Methods LITT was performed in adult Lewis rats with implanted glioma cells in the brain using a standard exposure of 3 W for 30 seconds. Before and following LITT, neoplastic lesions were monitored by MRI. Proliferation of implanted cells and gliosis were assessed by several histological techniques and immunohistochemi…
Tenascin expression patterns and cells of monocyte lineage: relationship in human gliomas.
2000
Stromal extracellular matrix (ECM) components are thought to play an important role in regulating invasion of human gliomas. Macrophages and microglial cells may heavily influence the integrity of the extracellular compartment of gliomas, and the affected ECM may play a key role in regulating migratory activity of both tumor cells and macrophages/microglia. The aim of this investigation was to study immunohistochemically the expression patterns of four ECM components: fibronectin, laminin, collagen IV, and tenascin (TN) in human gliomas, with special attention to TN. Our main goal was to study the possible correlation between TN expression and macrophagic/microglial infiltration in gliomas.…
T2 mapping of the peritumoral infiltration zone of glioblastoma and anaplastic astrocytoma.
2021
Purpose To characterise peritumoral zones in glioblastoma and anaplastic astrocytoma evaluating T2 values using T2 mapping sequences. Materials and methods In this study, 41 patients with histopathologically confirmed World Health Organization high grade gliomas and preoperative magnetic resonance imaging examinations were retrospectively identified and enrolled. High grade gliomas were differentiated: (a) by grade, glioblastoma versus anaplastic astrocytoma; and (b) by isocitrate dehydrogenase mutational state, mutated versus wildtype. T2 map relaxation times were assessed from the tumour centre to peritumoral zones by means of a region of interest and calculated pixelwise by using a fit m…
Maximizing the Extent of Resection in High-Grade Glioma.
2019
High-grade gliomas (HGGs) are devastating tumors associated with one of the worst prognoses in oncology. Glioblastoma multiforme (GBM) is the most frequently reported histologic type, with a median survival after surgery and combined treatment with chemotherapy and radiotherapy of 12–16 months. Several studies have shown that the extent of resection (EOR) of the contrast-enhancing part of the tumor improves survival in patients with HGGs, although the quest to achieve optimal oncologic outcomes must be tempered with the neurologic result following radical resection. To date, limited evidence exists on the relationship between EOR and level of clinical benefit for patients with HGGs. Brown e…
Understanding the clinical behavior of relapsed colon cancers with microsatellite instability relative to BRAF mutations
2019
Background Microsatellite instable/deficient mismatch repair (MSI/dMMR) metastatic colorectal cancers have been reported to have a poor prognosis. Frequent co-occurrence of MSI/dMMR and BRAFV600E complicates the association. Patients and methods Patients with resected stage III colon cancer (CC) from seven adjuvant studies with available data for disease recurrence and MMR and BRAFV600E status were analyzed. The primary end point was survival after recurrence (SAR). Associations of markers with SAR were analyzed using Cox proportional hazards models adjusted for age, gender, performance status, T stage, N stage, primary tumor location, grade, KRAS status, and timing of recurrence. Results A…
Oral temozolomide in heavily pre-treated brain metastases from non-small cell lung cancer: phase II study
2005
Introduction: The primary tumour type most likely to metastasize to the brain is lung cancer. In heavily pre-treated patients, limited therapeutic option is available and the results of availability therapies reported in literature are disappointing. The present phase II study was designed to assess the efficacy and safety of temozolomide (TMZ) as palliative treatment for brain metastases (BrM) in NSCLC patients pre-treated with WBRT and at least one line of chemotherapy for metastatic brain disease. Material and methods: Temozolomide was administered orally at 150 mg/mq/day for five consecutive days for the first cycle, doses were increased to 200 mg/mq/day for 5 days every 28 days for sub…
Automated quality control protocol for MR spectra of brain tumors.
2008
Item does not contain fulltext eTUMOUR (http://www.etumour.net/) is acquiring a large database of brain tumor (1)H MR spectra to develop automated pattern recognition methods and decision support system (DSS) for tumor diagnosis. Development of accurate pattern-recognition algorithms requires spectra undistorted by artifacts, low signal-to-noise, or broad lines. eTUMOUR currently uses panels of expert spectroscopists to subjectively grade spectra as being acceptable or unacceptable. Automated quality control (QC) would be more satisfactory for several reasons: 1) to provide a reproducible objective classification of spectrum quality; 2) for use within the future DSS to prevent misdiagnosis …
The radiosensitization effect of titanate nanotubes as a new tool in radiation therapy for glioblastoma: A proof-of-concept
2013
Abstract Background and purpose One of the new challenges to improve radiotherapy is to increase the ionizing effect by using nanoparticles. The interest of titanate nanotubes (TiONts) associated with radiotherapy was evaluated in two human glioblastoma cell lines (SNB-19 and U87MG). Materials and methods Titanate nanotubes were synthetized by the hydrothermal treatment of titanium dioxide powder in a strongly basic NaOH solution. The cytotoxicity of TiONts was evaluated on SNB-19 and U87MG cell lines by cell proliferation assay. The internalization of TiONts was studied using Transmission Electron Microscopy (TEM). Finally, the effect of TiONts on cell radiosensitivity was evaluated using …
A radiosensitizing effect of artesunate in glioblastoma cells is associated with a diminished expression of the inhibitor of apoptosis protein surviv…
2011
Abstract Background and purpose Novel strategies to overcome an irradiation resistant phenotype may help to increase therapeutic efficacy in glioblastoma multiforme. The present study aimed to elucidate radiation sensitizing properties of artesunate, a semi synthetic derivate of artemisinin and to assess factors involved in this effect. Materials and methods LN229 and U87MG cells were treated with various concentrations of artesunate and radiation response was determined by a colony forming assay. Cell numbers, apoptosis induction, cell cycle distribution, and DNA repair following combined modality treatment were monitored by MTT-, caspase 3/7 assay, cytofluorometry, and γ-H2AX foci formati…