Navegando por Palavras-chave "glioma"
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- ItemAcesso aberto (Open Access)Associação de malformação vascular e gliomas: estudo de quatro casos(Academia Brasileira de Neurologia - ABNEURO, 2003-06-01) Borges, Lia Raquel R. [UNIFESP]; Malheiros, Suzana Maria Fleury [UNIFESP]; Pelaez, Maria Paula [UNIFESP]; Stávale, João Norberto [UNIFESP]; Santos, Adrialdo J. [UNIFESP]; Carrete Junior, Henrique [UNIFESP]; Nogueira, Roberto Gomes [UNIFESP]; Ferraz, Fernando A. P. [UNIFESP]; Gabbai, Alberto Alain [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)We reviewed the clinical presentation, imaging and histopathologic findings in 4 patients with the diagnosis of arteriovenous malformation associated with glioma that were operated on from 1991 to 2000 in our institution. Four patients (2 males; age between 15 and 52 years) presented with progressive headache with clinical evidence of intracranial hypertension (in 3) and partial seizures (in 1). CT scan showed a brain tumor without any detectable pathologic vessels. Histologic examination revealed astrocytic tumors associated with arteriovenous malformation. No patient presented the vascular component intermixed with the tumor. The arteriovenous-glioma association is rare and must be identified by a clear demarcation between the malformation and the tumor.
- ItemSomente MetadadadosBiópsia estereotáxica guiada por imagem nas lesões do sistema nervoso central(Assoc Arquivos De Neuro- Psiquiatria, 1998-06-01) Nasser, José Augusto [UNIFESP]; Confort, Carlos Ivam; Ferraz, Andrei; Esperança, José Carlos; Duarte, Francisco; Universidade Federal de São Paulo (UNIFESP); Universidade Federal do Rio de Janeiro (UFRJ)In a series of 44 image guided stereotactic biopsy from August 1995 until March 1997, findings were as follows (frequency order). Turners, glioblastoma. was the most frequent. Primary lymphoma and other conditions associated to AIDS. Metastasis, three cases. Vasculites, two cases. Arachnoid cyst, Creutzfeldt-Jakob, cortical degeneration, inespecific calcification tone case each). The age varied from 1 to 83 years. Forty one lesions were supratentorial, two infratentorial, and one was outside the brain (dura and skull) and we used stereotaxy to localize it. There was no mortality and morbidity was 2.3%. The literature is reviewed. We conclude that this procedure is safe and highly diagnostic.
- ItemAcesso aberto (Open Access)Gliomas múltiplos: casos ilustrativos de quatro formas de apresentação(Academia Brasileira de Neurologia - ABNEURO, 2000-03-01) Franco, Clélia Maria Ribeiro [UNIFESP]; Malheiros, Suzana Maria Fleury [UNIFESP]; Nogueira, Roberto Gomes [UNIFESP]; Batista, Marcus Azzar Sabry [UNIFESP]; Santos, Adrialdo José [UNIFESP]; Abdala, Nitamar [UNIFESP]; Stávale, João Norberto [UNIFESP]; Ferraz, Fernando Antônio Patriani [UNIFESP]; Gabbai, Alberto Alain [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Multiple gliomas are uncommon and may be classified according to: a) the time of presentation in early (at diagnosis) or late (during treatment); b) the characteristics of computed tomography or magnetic resonance imaging (CT/MRI) in multifocal (with evidence of spread) and multicentric (without evidence of spread). From 212 patients with histopathologic diagnosis of glioma evaluated from March/90 to September/99, 15 (7%) had multiple lesions. We describe 4 patients: early multicentric, late multicentric, early multifocal and late multifocal, with emphasis on characteristics of CT/MRI and possible differential diagnosis. The differential diagnosis of multiple lesions in the central nervous system includes mainly infectious/inflammatory diseases and metastasis, however multiple gliomas should always be considered, even in patients with known systemic cancer, as described by others. Considering that CT/MRI features are not definite, the diagnosis should always be confirmed by histopathologic examination.
- ItemAcesso aberto (Open Access)Índice de astrócitos gemistocíticos e imuno-expressão da proteína p53 em astrocitomas, grau II e III OMS(Academia Brasileira de Neurologia - ABNEURO, 2001-12-01) Martins, Dely Cristina [UNIFESP]; Stávale, João Norberto [UNIFESP]; Malheiros, Suzana Maria Fleury [UNIFESP]; Santiago, Lucila Heloisa Simardi [UNIFESP]; Roman, Leonor Cristina Manoja [UNIFESP]; Aguiar, Kátia Cilene Carozzi [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Twenty-two patients with astrocytomas, grade II or III WHO, were studied from 1990 to 1998. In all cases, histopathology showed that the astrocytomas had a gemistocytic component. The aims of this study were to establish the fraction of gemistocytic astrocytes, to investigate p53 protein immunoexpression and to evaluate correlations between these two parameters with the tumour outcome. Tumor cells were quantified at high-power magnification (x400). At least 1000 neoplastic cells (small neoplastic astrocytes plus gemistocytes) were counted in each specimen. The percentage of gemistocytes was defined as the gemistocytic index. Nuclear expression of p53 protein was evaluated in neoplastic astrocytes and gemistocytes. Both the frequency (7/22) as well the p53 immunoexpression indices in gemistocytes, regardless of the grade of the astrocytomas, were inferior from those reported in the literature. No correlation was found between the gemistocytic indices and the p53 immunoexpression.
- ItemSomente MetadadadosMagnetofecção mediada por nanopartículas de óxido de ferro em tumores de glioblastoma para posterior aplicação terapêutica da magneto hipertermia: estudos in vitro e in vivo(Universidade Federal de São Paulo (UNIFESP), 2015-12-18) Aguiar, Marina Fontes de Paula [UNIFESP]; Contreras, Lionel Fernel Gamarra Contreras [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objective: Elucidate the in vitro and in vivo magnetofection process in glioblastoma tumors induced by C6 cells, with future perspective for therapeutic application of magneto hyperthermia. Therefore, superparamagnetic iron oxide nanoparticles conjugated with fluorescent Rhodamine-B molecules were used along with an external magnetic field for active tumor targeting. Methods: For magnetofection process, a resistive electromagnet capable of generating a variable magnetic field and pole geometry able to create a magnetic field gradient, was built. Previous in vitro tests with 50 nm hydrodynamic size NOFRhod were made to verify the transport and specific local accumulation. For in vivo targeting, the magnetic field of the poles was adjusted to 0 T (control) or 1,3 T (experimental value) and the nanoparticles were administrated by three different routes: tumor local, tail vein or carotid artery. Results: At first, we demonstrated that nanoparticles in this study are stable in DMEM culture medium and when dispersed in saline or PBS at a concentration of 50 µgFe/mL. The cell labeling analysis by prussian blue and fluorescent microscopy showed that NOF-Rhod are efficient for this purpose in all used concentrations (1, 10, 30 e 50 ug/mL), being enhanced by external magnetic field application. Besides that, cytotoxicity assay showed that cell death caused by these nanoparticles was barely evident. The volumetry study by MRI and histology demonstrated that in all used concentrations the tumor growth was evident and proportional both according to the day and the C6 cell concentration (104 , 105 ou 106 ). The in vitro tests showed that nanoparticle aggregation was efficient in all magnetic field gradients used. Moreover, the oblique steel pole addition created a punctual nanoparticle accumulation in one hose?s side, being this artifice selected for subsequent in vivo studies. The MRI monitoring was effective for NOF-Rhod identification in tumor region after local administration, showed an important signal reduction. The MRI sensibility, moreover, was not able to detect NOF-Rhod in tumor region after tail vein or carotid administration, further studies for these administration parameters are required. The in vivo magnetofection process analysis by histology, however, demonstrated more sensibility than MRI, evidencing iron concentration in tumor after the three NOFRhod administration routes. Furthermore, targeting intravenous administration with an external magnetic field was capable to increasing nanoparticle accumulation in tumor region. Conclusion: Taken together, our in vitro and in vivo results showed the NOF-Rhod magnetic targeting efficience, being this strategy a promisse tool for further applications of magneto hyperthermia technique.
- ItemSomente MetadadadosStereotactic biopsy guidance in adults with supratentorial nonenhancing gliomas: role of perfusion-weighted magnetic resonance imaging(Amer Assoc Neurological Surgeons, 2004-12-01) Maia, ACM; Malheiros, SMF; Da Rocha, A. J.; Stavale, J. N.; Guimaraes, I. F.; Borges, LRR; Santos, A. J.; Da Silva, C. J.; De Melo, JGSP; Lanzoni, O. P.; Gabbai, Alberto Alain [UNIFESP]; Ferraz, FAP; Universidade Federal de São Paulo (UNIFESP)Object. the diagnosis of low-grade glioma (LGG) cannot be based exclusively on conventional magnetic resonance (MR) imaging studies, and target selection for stereotactic biopsy is a crucial issue given the high risk of sampling errors. the authors hypothesized that perfusion-weighted imaging could provide information on the microcirculation in presumed supratentorial LGGs.Methods. All adult patients with suspected (nonenhancing) supratentorial LGGs on conventional MR imaging between February 2001 and February 2004 were included in this study. Preoperative MR imaging was performed using a dynamic first-pass gadopentate dimeglumine-enhanced spin echo-echo planar perfusion-weighted sequence, and the tumors' relative cerebral blood volume (rCBV) measurements were expressed in relation to the values observed in contralateral white matter. in patients with heterogeneous tumors a stereotactic biopsy was performed in the higher perfusion areas before resection. Among 21 patients (16 men and five women with a mean age of 36 years, range 23-60 years), 10 had diffuse astrocytomas (World Health Organization Grade II) and 11 had other LGGs and anaplastic gliomas. On perfusion-weighted images demonstrating heterogeneous tumors, areas of higher rCBV focus were found to be oligodendrogliornas or anaplastic astrocytomas on stereotactic biopsy; during tumor resection, however, specimens were characterized predominantly as astrocytomas. Diffuse astrocytomas were associated with significantly lower mean rCBV values compared with those in the other two lesion groups (p < 0.01). the rCBV ratio cutoff value that permitted better discrimination between diffuse astrocytomas and the other lesion groups was 1.2 (80% sensitivity and 100% specificity).Conclusions. Perfusion-weighted imaging is a feasible method of reducing the sampling error in the histopathological diagnosis of a presumed LGG, particularly by improving the selection of targets for stereotactic biopsy.
- ItemSomente MetadadadosVoltage-Gated Proton Channel in Human Glioblastoma Multiforme Cells(Amer Chemical Soc, 2016) Ribeiro-Silva, Luisa [UNIFESP]; Queiroz, Fernanda Oliveira [UNIFESP]; Brito da Silva, Annielle Mendes [UNIFESP]; Hirata, Aparecida Emiko [UNIFESP]; Arcisio-Miranda, Manoel [UNIFESP]Solid tumors tend to have a more glycolytic metabolism leading to an accumulation of acidic metabolites in their cytosol, and consequently, their intracellular pH (pH(i)) turns critically lower if the cells do not handle the acid excess. Recently, it was proposed that the voltage gated proton channels (H(v)1) can regulate the pH(i) in several cancers. Here we report the functional expression of voltage gated proton channels in a human glioblastoma multiforme (GBM) cell line, the most common and lethal brain tumor. T98G cells presented an outward, slow activating voltage-dependent proton current, which was also Delta pH-dependent and inhibited by ZnCl2, characterizing it as being conducted by H(v)1 channels. Furthermore, blocking H(v)1 channels with ZnCl2 significantly reduced the pH(i), cell survival, and migration, indicating an important role for H(v)1 for tumor proliferation and progression in GBM. Overall, our results suggest that H(v)1 channels can be a new therapeutic target for GBM.