311 resultados para Glioblastoma Multiforme
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The Stevens-Johnson syndrome is a severe potentially life-threatening form of the erythema multiforme, affecting both skin and mucous membranes. We present a case of a 49-year-old male patient with AIDS who developed a Stevens-Johnson syndrome while being treated with pyrimethamine, sulfadiazine and phenytoin for cerebral toxoplasmosis. Further diagnostic evaluation of this dangerous cutaneous affection may prove difficult for several reasons. In particular, in patients with AIDS who are more susceptible for adverse drug reactions and who are simultaneously receiving a variety of drugs with a considerable potential of cutaneous side effects, therapy cannot be withhold for lack of therapeutic alternatives. Moreover, the low lymphocyte count in this case may have made reliable testing with lymphocyte transformation studies impossible. The evaluation and the differential diagnosis of the drug-induced Stevens-Johnson syndrome are discussed. Especially long- and moderately long-acting sulfonamides belong to the most important agents that can cause a drug-induced Stevens-Johnson syndrome. The pathogenesis and the risk factors for cutaneous hypersensitivity reactions in HIV-infected patients are only poorly understood. These kind of reactions, however, seem to occur more often in patients with a more advanced immunodeficiency.
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We report the case of an HIV-infected man returning from Thailand with secondary syphilis with general symptoms, hepatitis and a pulmonary mass lesion. A cerebrospinal fluid examination showed no signs of neurosyphilis. Two months after successful treatment with benzathine penicillin he presented with a mass lesion in the brain suspected to be a glioma or glioblastoma, which turned out to be a syphilitic gumma. Syphilis remains a great imitator in clinical medicine. Syphilitic brain gummata can develop within a few months.
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OBJECT Resection of glioblastoma adjacent to motor cortex or subcortical motor pathways carries a high risk of both incomplete resection and postoperative motor deficits. Although the strategy of maximum safe resection is widely accepted, the rates of complete resection of enhancing tumor (CRET) and the exact causes for motor deficits (mechanical vs vascular) are not always known. The authors report the results of their concept of combining monopolar mapping and 5-aminolevulinic acid (5-ALA)-guided surgery in patients with glioblastoma adjacent to eloquent tissue. METHODS The authors prospectively studied 72 consecutive patients who underwent 5-ALA-guided surgery for a glioblastoma adjacent to the corticospinal tract (CST; < 10 mm) with continuous dynamic monopolar motor mapping (short-train interstimulus interval 4.0 msec, pulse duration 500 μsec) coupled to an acoustic motor evoked potential (MEP) alarm. The extent of resection was determined based on early (< 48 hours) postoperative MRI findings. Motor function was assessed 1 day after surgery, at discharge, and at 3 months. RESULTS Five patients were excluded because of nonadherence to protocol; thus, 67 patients were evaluated. The lowest motor threshold reached during individual surgery was as follows (motor threshold, number of patients): > 20 mA, n = 8; 11-20 mA, n = 13; 6-10 mA, n = 10; 4-5 mA, n = 13; and 1-3 mA, n = 23. Motor deterioration at postsurgical Day 1 and at discharge occurred in 30% (n = 20) and 10% (n = 7) of patients, respectively. At 3 months, 3 patients (4%) had a persisting postoperative motor deficit, 2 caused by vascular injury and 1 by mechanical injury. The rates of intra- and postoperative seizures were 1% and 0%, respectively. Complete resection of enhancing tumor was achieved in 73% of patients (49/67) despite proximity to the CST. CONCLUSIONS A rather high rate of CRET can be achieved in glioblastomas in motor eloquent areas via a combination of 5-ALA for tumor identification and intraoperative mapping for distinguishing between presumed and actual motor eloquent tissues. Continuous dynamic mapping was found to be a very ergonomic technique that localizes the motor tissue early and reliably.
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The present report describes the synthesis and biological evaluation of a molecular imaging platform based on gold nanoparticles directly labeled with indium-111. The direct labeling approach facilitated radiolabeling with high activities while maintaining excellent stability within the biological environment. The resulting imaging platform exhibited low interference of the radiolabel with targeting molecules, which is highly desirable for in-vivo probe tracking and molecular targeted tumor imaging. The indium-111 labeled gold nanoparticles were synthesized using a simple procedure that allowed stable labeling of the nanoparticle core with various indium-111 activities. Subsequent surface modification of the particle cores with RGD-based ligands at various densities allowed for molecular targeting of the αvß3 integrin in-vitro and for molecular targeted imaging in human melanoma and glioblastoma models in-vivo. The results demonstrate the vast potential of direct labeling with radioisotopes for tracking gold nanoparticles within biological systems.
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Diffusely infiltrating gliomas are among the most prognostically discouraging neoplasia in human. Temozolomide (TMZ) in combination with radiotherapy is currently used for the treatment of glioblastoma (GBM) patients, but less than half of the patients respond to therapy and chemoresistance develops rapidly. Epigenetic silencing of the O(6)-methylguanine-DNA methyltransferase (MGMT) has been associated with longer survival in GBM patients treated with TMZ, but nuclear factor κB (NF-κB)-mediated survival signaling and TP53 mutations contribute significantly to TMZ resistance. Enhanced NF-κB is in part owing to downregulation of negative regulators of NF-κB activity, including Tumor necrosis factor alpha-induced protein 3 (TNFAIP3) and NF-κB inhibitor interacting RAS-like 2 (NKIRAS2). Here we provide a novel mechanism independent of TP53 and MGMT by which oncogenic miR-125b confers TMZ resistance by targeting TNFAIP3 and NKIRAS2. GBM cells overexpressing miR-125b showed increased NF-κB activity and upregulation of anti-apoptotic and cell cycle genes. This was significantly associated with resistance of GBM cells to TNFα- and TNF-related inducing ligand-induced apoptosis as well as resistance to TMZ. Conversely, overexpression of anti-miR-125b resulted in cell cycle arrest, increased apoptosis and increased sensitivity to TMZ, indicating that endogenous miR-125b is sufficient to control these processes. GBM cells overexpressing TNFAIP3 and NKIRAS2 were refractory to miR-125b-induced apoptosis resistance as well as TMZ resistance, indicating that both genes are relevant targets of miR-125b. In GBM tissues, high miR-125b expression was significantly correlated with nuclear NF-κB confirming that miR-125b is implicated in NF-κB signaling. Most remarkably, miR-125b overexpression was clearly associated with shorter overall survival of patients treated with TMZ, suggesting that this microRNA is an important predictor of response to therapy.
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Various in-vitro chemosensitivity and resistance assays (CSRAs) have been demonstrated to be helpful decision aids for non-neurological tumors. Here, we evaluated the performance characteristics of two CSRAs for glioblastoma (GB) cells. The chemoresponse of fresh GB cells from 30 patients was studied in vitro using the ATP tumor chemoresponse assay and the chemotherapy resistance assay (CTR-Test). Both assay platforms provided comparable results. Of seven different chemotherapeutic drugs and drug combinations tested in vitro, treosulfan plus cytarabine (TARA) was the most effective, followed by nimustine (ACNU) plus teniposide (VM26) and temozolomide (TMZ). Whereas ACNU/VM26 and TMZ have proven their clinical value for malignant gliomas in large randomized studies, TARA has not been successful in newly diagnosed gliomas. This seeming discrepancy between in vitro and clinical result might be explained by the pharmacological behavior of treosulfan. Our results show reasonable agreement between two cell-based CSRAs. They appear to confirm the clinical effectiveness of drugs used in GB treatment as long as pharmacological preconditions such as overcoming the blood-brain barrier are properly considered.
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BACKGROUND Prior epidemiologic studies suggest inverse relations between diabetes and glioma risk, but the underlying mechanisms, including use of antidiabetic drugs, are unknown. METHODS We therefore performed a matched case-control analysis using the Clinical Practice Research Datalink (CPRD). We identified incident glioma cases diagnosed between 1995 and 2012 and matched each case with 10 controls on age, gender, calendar time, general practice, and years of active history in the CPRD. We performed conditional logistic regression to estimate odds ratios (ORs) with 95% CIs, adjusted for body mass index and smoking. RESULTS We identified 2005 cases and 20 050 controls. Diabetes was associated with decreased risk of glioma (OR = 0.74; 95% CI = 0.60-0.93), particularly glioblastoma (OR = 0.69; 95% CI = 0.51-0.94). Glioblastoma risk reduction was markedly pronounced among diabetic men (OR = 0.60; 95% CI = 0.40-0.90), most apparently for those with diabetes of long-term duration (OR for >5 vs 0 y = 0.46; 95% CI = 0.26-0.82) or poor glycemic control (OR for HbA1c ≥8 vs <6.5% = 0.20; 95% CI = 0.06-0.70). In contrast, the effect of diabetes on glioblastoma risk was absent among women (OR = 0.85; 95% CI = 0.53-1.36). No significant associations with glioma were found for use of metformin (OR for ≥30 vs 0 prescriptions = 0.72; 95% CI = 0.38-1.39), sulfonylureas (OR = 0.71; 95% CI = 0.39-1.30), or insulin (OR = 0.79; 95% CI = 0.37-1.69). CONCLUSIONS Antidiabetic treatment appears to be unrelated to glioma, but long-term diabetes duration and increased HbA1c both show decreased glioma risk. Stronger findings in men than women suggest low androgen levels concurrent with diabetes as a biologic mechanism.
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BACKGROUND Maculopapular or urticarial eruptions and erythema multiforme sometimes occur in patients affected with Mycoplasma pneumoniae respiratory infections. Further eruptions have also been reported. OBJECTIVE To review the literature addressing M. pneumoniae respiratory infection and rather unusual eruptions. METHODS Computer-based search in the U.S. National Library of Medicine database as well as in the search engine Google. RESULTS We found a possible relationship between M. pneumoniae infection and Fuchs' syndrome (n = 37), varicella-like eruptions (n = 8), Henoch-Schönlein syndrome and further leukocytoclastic vasculitides (n = 21) and erythema nodosum (n = 11). A temporal relationship was also observed with 2 cases of Gianotti-Crosti syndrome. Finally, there exists reasonable evidence that pityriasis rosea Gibert and pityriasis lichenoides et varioliformis acuta Mucha-Habermann are not associated with Mycoplasma infections. CONCLUSION This review implies that M. pneumoniae may cause, in addition to erythematous maculopapular (or urticarial) eruptions and erythema multiforme, Fuchs' syndrome and varicella-like eruptions. Furthermore, there is an intriguing link with leukocytoclastic vasculitides or erythema nodosum that deserves further investigation.
Clinical Evaluation of a Fully-automatic Segmentation Method for Longitudinal Brain Tumor Volumetry.
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Information about the size of a tumor and its temporal evolution is needed for diagnosis as well as treatment of brain tumor patients. The aim of the study was to investigate the potential of a fully-automatic segmentation method, called BraTumIA, for longitudinal brain tumor volumetry by comparing the automatically estimated volumes with ground truth data acquired via manual segmentation. Longitudinal Magnetic Resonance (MR) Imaging data of 14 patients with newly diagnosed glioblastoma encompassing 64 MR acquisitions, ranging from preoperative up to 12 month follow-up images, was analysed. Manual segmentation was performed by two human raters. Strong correlations (R = 0.83-0.96, p < 0.001) were observed between volumetric estimates of BraTumIA and of each of the human raters for the contrast-enhancing (CET) and non-enhancing T2-hyperintense tumor compartments (NCE-T2). A quantitative analysis of the inter-rater disagreement showed that the disagreement between BraTumIA and each of the human raters was comparable to the disagreement between the human raters. In summary, BraTumIA generated volumetric trend curves of contrast-enhancing and non-enhancing T2-hyperintense tumor compartments comparable to estimates of human raters. These findings suggest the potential of automated longitudinal tumor segmentation to substitute manual volumetric follow-up of contrast-enhancing and non-enhancing T2-hyperintense tumor compartments.
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Analysis of the human genome has revealed that more than 74% of human genes undergo alternative RNA splicing. Aberrations in alternative RNA splicing have been associated with several human disorders, including cancer. ^ We studied the aberrant expression of alternative RNA splicing isoforms of the Fibroblast Growth Factor Receptor 1 (FGFR1) gene in a human glioblastoma cancer model. Normal glial cells express the FGFR1α, which contains three extracellular domains. In tumors the most abundant isoform is the FGFR1β, which lacks the first extracellular domain due to the skipping of a single exon, termed alpha. The skipping of the α-exon is regulated by two intronic silencing sequences within the precursor mRNA. Since we observed no mutations on these elements in tumor cells, we hypothesized that the over-expression of regulatory proteins that recognize these sequences is responsible for the aberrant expression of splicing isoforms. Hence, we blocked the formation of protein complexes on the ISS using antisense RNA oligonucleotides in vitro. We also evaluated the impact of the ISS antisense oligonucleotides on the endogenous FGFR1 splicing, in a glioblastoma cell model. By targeting intronic regulatory elements we were able to increase the level of alpha exon inclusion up to 90% in glioblastoma cells. The effect was dose dependent, sequence specific and reproducible in glioblastoma and other cancer cells, which also exhibit an alpha exon skipping phenotype. Targeting FGFR1 endogenous ISS1 and ISS2 sequences did not have an additive or synergistic effect, which suggest a regulatory splicing mechanism that requires the interaction of complexes formed on these elements. An increase in the levels of the FGFR1α isoform resulted in a reduction in cell invasiveness. Also, a significant increase in the levels of caspase 3/7 activities, which is indicative of an elevation in apoptosis levels, suggests that expression of FGFR1β might be relevant for tumor survival. These studies demonstrate that it is possible to prevent aberrant expression of exon skipping events through the targeting of intronic regulatory elements, providing an important new therapeutic tool for the correction of human disease caused by alternative RNA splicing. ^
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Diffuse gliomas are highly lethal central nervous system malignancies which, unfortunately, are the most common primary brain tumor and also the least responsive to the very few therapeutic modalities currently available to treat them. IGFBP2 is a newly recognized oncogene that is operative in multiple cancer types, including glioma, and shows promise for a targeted therapeutic approach. Elevated IGFBP2 expression is present in high-grade glioma and correlates with poor survival. We have previously demonstrated that IGFBP2 induces glioma development and progression in a spontaneous glioma mouse model, which highlighted its significance and potential for future therapy. However, we did not yet know the key physiological pathways associated with this newly characterized oncogene. We first evaluated human glioma genomics data harnessed from the publicly available Rembrandt source to identify major pathways associated with IGFBP2 expression. Integrin and ILK, among other cell migration and invasion-related pathways, were the most prominently associated. We confirmed that these pathways are regulated by IGFBP2 in glioma cells lines, and demonstrated that 1) IGFBP2 activates integrin α5β1, leading to the activation of key pathways important in glioma; 2) IGFBP2 mediates cell migration pathways through ILK; and 3) IGFBP2 activates NF-kB via an integrin α5 interaction. We then sought to determine whether this was a physiologically active signaling pathway in vivo by assessing its ability to induce glioma progression in the RCAS/tv-a spontaneous glioma mouse model. We found that ILK is a key downstream mediator of IGFBP2 that is required for the induction of glioma progression. Most significantly, a genetic therapeutic approach revealed that perturbation of any point in the pathway thwarted tumor progression, providing strong evidence that targeting the key players could potentially produce a significant benefit for human glioma patients. The elucidation of this signaling pathway is a critical step, since efforts to create a small molecule drug targeting IGFBP2 have so far not been successful, but a number of inhibitors of the other pathway constituents, including ILK, integrin and NF-kB, have been developed.
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Fil: Rivarola, Emilce. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas
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La obra de Aub viene marcada por el sello de lo laberíntico, de its mundo interior obsesivo y multiforme que se express cuando y como pudo o le dejaron. No es por ello de extrañar que la elaboración de sus obras completes y la revision de sus papeles personales nos regale un sinfin de descubrimientos gratificantes. En mi trabajo como editor de Campo de sangre, en el rococo de las Obras completas del autor publicadas por la Biblioteca Valenciana, el hallazgo riles notable es el de los diversos cuadernos (quince, por ahora) que incluyen el esqueleto de la novela y sus primeros apuntes. El primer objetivo de este trabajo es intentar reconstruir el proceso genetico de la novela a partir de dicho material autógrafo, estableciendo unas hipótesis que el articulista sabe provisionales pero que pretender dar cuenta de un giro radical del autor entre su primera concepción de Campo de sangre y su redacción definitive. En segundo lugar, aunque de rnanera paralela, se pretende hacer que la labor mencionada contribuya a esclarecer la figura de Aub como creador y como hombre, en la medida en que dichas facetas seas separables.
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La obra de Aub viene marcada por el sello de lo laberíntico, de its mundo interior obsesivo y multiforme que se express cuando y como pudo o le dejaron. No es por ello de extrañar que la elaboración de sus obras completes y la revision de sus papeles personales nos regale un sinfin de descubrimientos gratificantes. En mi trabajo como editor de Campo de sangre, en el rococo de las Obras completas del autor publicadas por la Biblioteca Valenciana, el hallazgo riles notable es el de los diversos cuadernos (quince, por ahora) que incluyen el esqueleto de la novela y sus primeros apuntes. El primer objetivo de este trabajo es intentar reconstruir el proceso genetico de la novela a partir de dicho material autógrafo, estableciendo unas hipótesis que el articulista sabe provisionales pero que pretender dar cuenta de un giro radical del autor entre su primera concepción de Campo de sangre y su redacción definitive. En segundo lugar, aunque de rnanera paralela, se pretende hacer que la labor mencionada contribuya a esclarecer la figura de Aub como creador y como hombre, en la medida en que dichas facetas seas separables.
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La obra de Aub viene marcada por el sello de lo laberíntico, de its mundo interior obsesivo y multiforme que se express cuando y como pudo o le dejaron. No es por ello de extrañar que la elaboración de sus obras completes y la revision de sus papeles personales nos regale un sinfin de descubrimientos gratificantes. En mi trabajo como editor de Campo de sangre, en el rococo de las Obras completas del autor publicadas por la Biblioteca Valenciana, el hallazgo riles notable es el de los diversos cuadernos (quince, por ahora) que incluyen el esqueleto de la novela y sus primeros apuntes. El primer objetivo de este trabajo es intentar reconstruir el proceso genetico de la novela a partir de dicho material autógrafo, estableciendo unas hipótesis que el articulista sabe provisionales pero que pretender dar cuenta de un giro radical del autor entre su primera concepción de Campo de sangre y su redacción definitive. En segundo lugar, aunque de rnanera paralela, se pretende hacer que la labor mencionada contribuya a esclarecer la figura de Aub como creador y como hombre, en la medida en que dichas facetas seas separables.