1,721,033 research outputs found
The emerging role of stereotactic radiosurgery in the treatment of Glioblastoma multiforme
No full textStereotactic radiosurgery is an emerging treatment option offered to patients with Glioblastoma multiforme (GBM). Radiosurgery is performed as an outpatient procedure and provides a safe and effective non invasive treatment for focal GBM. High energy beams originating from cobalt sources placed into an helmet (Gamma-Knife) or generated by a linear accelerator (LINAC) rotating on a gantry (X-Knife, Novalis) or maneuvered by a robotic arm (CyberKnife) are delivered with submillimetric accuracy to a selected intracranial target. Treatment accuracy is provided by image-guided volumetric CT and MR studies complemented with advanced metabolic neuroimaging techniques such as CT-PET. Radiosurgery is typically used as a salvage treatment in patients with recurrent GBM to avoid further surgical procedures or as a complement to conventional fractionated radiotherapy. This paper reviews the emerging role of stereotactic radiosurgery in the treatment of GBM. © 2012 Bentham Science Publishers
A case of intracranial meningioma detected by 18F-choline PET/CT and examined by PET/MRI fusion imaging
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Synthesis and characterisation of poly(2-hydroxyethyl methacrylate) polyelectrolyte complexes
No full textCopolymerisation of charged and neutral monomers is a well-known methodology to introduce charged moieties in a polymeric chain to obtain polyelectrolytes. New polyelectrolyte complexes have been synthesised by radical copolymerisation of neutral methacrylic monomer 2-hydroxyethyl methacrylate (HEMA) with cationic 2-methacryloyloxyethyltrimethyl ammonium chloride and anionic 2-acrylamido-2-methylpropane-sulphonic acid monomers in 10 : 1 : 1 and 10 :1 : 2 stechiometric ratio. Chemical structure of the synthesised terpolymers was confirmed by FT-IR spectroscopy, moreover, X-ray photoelectron spectroscopy showed the presence of a cationic charge excess on the 10 : 1 : 2 terpolymer surface with respect to 10 : 1 : 1 terpolymer. Swelling studies for 10 : 1 : 2 terpolymers showed a high water content in the swollen state and a "smart behaviour" upon changes in external stimuli such as pH, while, 10 : 1 : 1 terpolymer presented the behaviour of a neutral polymer. Mechanical and differential scanning calorimetry analysis confirmed that terpolymer networks were stabilised by ionic co-operative interactions. Infact, the inclusion of oppositely ionic charges in the polymeric network of p(HEMA) represent a way to achieve higher elastic modulus as they stabilise the terpolymer networks. Cytotoxicity and cytocompatibility studies demonstrated that all materials were not toxic, moreover, the presence of a cationic charge excess on 10 : 1 : 2 terpolymer surface was able to promote fibroblast adhesion
From cell-ECM interactions to tissue engineering.
No full textThe extracellular matrix (ECM) consists of a complex mixture of structural and functional macromolecules and serves an important role in tissue and organ morphogenesis and in the maintenance of cell and tissue structure and function. The great diversity observed in the morphology and composition of the ECM contributes enormously to the properties and function of each organ and tissue. The ECM is also important during growth, development, and wound repair: its own dynamic composition acts as a reservoir for soluble signaling molecules and mediates signals from other sources to migrating, proliferating, and differentiating cells. Approaches to tissue engineering center on the need to provide signals to cell populations to promote cell proliferation and differentiation. These "external signals" are generated from growth factors, cell-ECM, and cell-cell interactions, as well as from physical-chemical and mechanical stimuli. This review considers recent advances in knowledge about cell-ECM interactions. A description of the main ECM molecules and cellular receptors with particular care to integrins and their role in stimulation of specific types of signal transduction pathways is also explained. The general principles of biomaterial design for tissue engineering are considered, with same examples
Surgery, radiotherapy and temozolomide in treating high-grade gliomas
No full textTemozolomide (TMZ) a recent, oral, second generation alkylating agent is a chemotherapeutic with demonstrated efficacy for the treatment of high-grade gliomas. The efficacy of TMZ has been demonstrated in both pre-clinical and phase I and II studies. The goal of this study is to determine the activity and safety of temozolomide in improving overall survival (OS), progression-free survival (PFS) and health-related quality of life (HQL) in patient with malignant gliomas treated by surgery, radiotherapy and temozolomide. Twelve patients with newly diagnosed glioblastoma (GBM), and anaplastic astrocytoma (AA) were studied. The mean follow-up period was 12 months. The overall response rate for all histological groups was 33% (4 patients), 6 patients (50%) showed a stabilization of disease. The median progression-free survival (PFS) and overall survival (OS) was respectively 8.35 and 14.1 months; time to progression was 36 week ranging from 20 to 46 In all patients, treatment with temozolomide was associated with improvement of performance status including the patient showing disease progression; Karnofski score improved in all patients by a minimum of 10, with a median of 20 at 6 months. No patient stopped the treatment due to side-effects, no major adverse events were recorded. In two cases of glioblastoma, we observed complete response and after three years, the quality of life is optimal. Surgery allows to establish a histopathological diagnosis, to improve signs and symptoms which are attributable to intracranial hypertension or tumour topography, and to reduce the number of target cells for adjunctive therapies. Radiotherapy improves survival and TMZ chemotherapy that is given after radiotherapy adds survival benefit for patients. Because of its favourable pharmacokinetic and pharmacodynamic properties and improved tolerability. Temozolomide appears to be an ideal, first-line, single-agent, with a safe profile and demonstrated HQL benefits in patients with high-grade gliomas
β-Tricalcium phosphate 3D scaffold promote alone osteogenic differentiation of human adipose stem cells: In vitro study
No full textHuman adipose tissues surgically resected from the subcutaneous abdominal region were enzymatically processed to obtain Human Adipose Stem cells (fibroblast-like adipose tissue-derived stromal cells-ADSC-FL) that were immunophenotypically characterized using a panel of mesenchymal markers by flow cytometry. The formation of new hydroxyapatite crystals in culture dishes, by differentiating cells, further demonstrate the osteogenic potential of purified cells. The aim of this study was to evaluate the osteogenic differentiation potential of ADSC-FL seeded onto a porous β-tricalcium phosphate (β-TCP) matrix. ADSC-FL was cultured on the β-TCP matrix in medium with or without osteogenic differentiation additives. Time-dependent cell differentiation was monitored using osteogenic markers such as alkaline phosphatase (activity assay), osteocalcin and ostopontin (ELISA method) expression. Our results reveal that β-TCP triggers the differentiation of ADSC-FL toward an osteoblastic phenotype irrespective of whether the cells are grown in a proliferative or a differentiative medium. Hence, a β-TCP matrix is sufficient to promote osteoblastic differentiation of ADSC-FL. However, in proliferative medium, alkaline phosphatase activity was detected at lower level respect to differentiative medium and osteocalcin and osteopontin showed an expression delay in cells cultured in proliferative medium respect to differentiative one. Moreover, we observed an increase in FAK phosphorylation at level of tyrosine residue in position 397 (Western-blot) that indicates a good cell adhesion to β-TCP scaffold. In conclusion, our paper demonstrates that a three-dimensional β-TCP scaffold in vitro triggers on its own the differentiation of ADSC-FL toward an osteoblastic phenotype without the need to use differentiative media. © 2009 Springer Science+Business Media, LLC.Human adipose tissues surgically resected from the subcutaneous abdominal region were enzymatically processed to obtain Human Adipose Stem cells (fibroblast-like adipose tissue-derived stromal cells-ADSC-FL) that were immunophenotypically characterized using a panel of mesenchymal markers by flow cytometry. The formation of new hydroxyapatite crystals in culture dishes, by differentiating cells, further demonstrate the osteogenic potential of purified cells. The aim of this study was to evaluate the osteogenic differentiation potential of ADSC-FL seeded onto a porous beta-tricalcium phosphate (beta-TCP) matrix. ADSC-FL was cultured on the beta-TCP matrix in medium with or without osteogenic differentiation additives. Time-dependent cell differentiation was monitored using osteogenic markers such as alkaline phosphatase (activity assay), osteocalcin and ostopontin (ELISA method) expression. Our results reveal that beta-TCP triggers the differentiation of ADSC-FL toward an osteoblastic phenotype irrespective of whether the cells are grown in a proliferative or a differentiative medium. Hence, a beta-TCP matrix is sufficient to promote osteoblastic differentiation of ADSC-FL. However, in proliferative medium, alkaline phosphatase activity was detected at lower level respect to differentiative medium and osteocalcin and osteopontin showed an expression delay in cells cultured in proliferative medium respect to differentiative one. Moreover, we observed an increase in FAK phosphorylation at level of tyrosine residue in position 397 (Western-blot) that indicates a good cell adhesion to beta-TCP scaffold. In conclusion, our paper demonstrates that a three-dimensional beta-TCP scaffold in vitro triggers on its own the differentiation of ADSC-FL toward an osteoblastic phenotype without the need to use differentiative media
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