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Background: Hemorrhagic lesions of the septum pellucidum are rare and usually occur in neonates. They can be due to a number of etiologies. Here, we report a rare case of adolescent nontraumatic septum pellucidum hemorrhage with a review of literature. Case Description: A 16-year-old girl presented with a 1-month history of gradual visual deterioration in the left eye, intermittent headache, and vomiting. Brain imaging showed hematoma located between the leaflets of the septum pellucidum with obstructive hydrocephalus. Transcallosal resection of interventricular mass was done. The patient was discharged with improved neurological symptoms; however, the left eye vision did not recover. Imaging demonstrated a unique anatomical variant in deep vascular structures. Conclusion: Cavum septum pellucidum hemorrhage is rare in adults. Many theories were constructed to explain its etiology. Bleeding due a vascular anatomical variant was not previously encountered. Understanding the embryological origin and anatomical details are important for proper clinical assessment and management of these patients.
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BACKGROUND: Neuroendocrine tumors (NET) are rare tumors with a low incidence of brain metastasis, especially in grade 1 NET. The most common source of brain metastasis is the lung. We present an unusual case of NET grade 1 with multiple hemorrhagic brain metastases. CASE DESCRIPTION: A 46-year-old woman, who initially presented with a seizure, was diagnosed with multiple brain and lung lesions. She was offered a biopsy for diagnosis, but she refused and lost to follow up. Eighteen years later, she developed progressive quadriparesis and confusion. A biopsy of the left frontal lobe lesions showed NET grade 1. A lung biopsy of the left upper lobe was consistent with the same diagnosis. The patient's functional status was poor with Eastern Cooperative Oncology Group (ECOG) grade 4. She only received palliative whole-brain radiation therapy (WBRT) and died 3 months after discharge. CLINICAL DISCUSSION: NET is a spectrum that encompasses benign to malignant cells. There is a female predominance in lower grades and male predominance in higher grades. No effective management for brain metastases was described, and the prognosis remains poor. CONCLUSION: Multiple brain metastases can be the first presentation of patients with NET. Early diagnosis and treatment may have a more favorable impact on the outcome of this disease. The longstanding numerous hemorrhagic NET brain metastases is exceedingly rare. The neuroimaging appearance is similar to other neoplastic and non-neoplastic lesions. An important differential diagnosis to consider is metastatic melanoma and choriocarcinoma, familial cavernous malformation, diffuse axonal injury, cerebral vasculitis, and amyloid angiopathy.
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BACKGROUND: Medulloblastoma (MB) is a malignant tumor of the central nervous system (CNS), and sarcoidosis is a chronic inflammatory disease of many organ systems, commonly affecting the lungs. No association between MB and sarcoidosis was described in the literature. MB and sarcoidosis have mutual molecular and signaling pathways that may predispose patients with sarcoidosis to develop MB. We describe a patient with sarcoidosis who developed MB. CASE DESCRIPTION: The patient is a 36-year-old diagnosed with pulmonary sarcoidosis presented with ataxia, bilateral horizontal nystagmus, diplopia, and bilateral upper limb dysmetria was found to have a cerebellar mass on magnetic resonance imaging (MRI). He was initially treated with corticosteroids as a case of neurosarcoidosis. The patient's symptoms worsened, and repeat MRI showed an increase in the tumor size with hydrocephalus. External ventricular drain insertion plus midline suboccipital craniotomy and resection of the tumor was performed. Pathology revealed MB classic type, sonic hedgehog-activated. There was no cerebrospinal fluid dissemination. He received craniospinal radiation and chemotherapy. Follow-up 20 months after radiation revealed residual neurologic symptoms and no recurrence on MRI brain. CONCLUSIONS: The exceedingly rare coexistence of adult MB and sarcoidosis may have a causal relationship based on specific common molecules. Leukotrienes, stimulation of astrocytes and Purkinje neurons, and the sonic hedgehog signaling pathway can be considered. Further genetic and molecular studies are merited.
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Doenças do Sistema Nervoso Central/complicações , Doenças do Sistema Nervoso Central/cirurgia , Neoplasias Cerebelares/complicações , Neoplasias Cerebelares/cirurgia , Meduloblastoma/complicações , Meduloblastoma/cirurgia , Sarcoidose/complicações , Sarcoidose/cirurgia , Corticosteroides/uso terapêutico , Adulto , Doenças do Sistema Nervoso Central/genética , Neoplasias Cerebelares/genética , Ventrículos Cerebrais , Craniotomia , Drenagem , Proteínas Hedgehog/genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Meduloblastoma/genética , Procedimentos Neurocirúrgicos/métodos , Polimorfismo de Nucleotídeo Único , Sarcoidose/genética , Resultado do Tratamento , Sequenciamento do ExomaRESUMO
BACKGROUND: Cutaneous meningioma is a very uncommon pathologic entity that can be divided into primary and secondary types. Secondary cutaneous meningioma arises from an intracranial meningioma through metastasis, seeding during surgery, or direct bone invasion. There are limited published case reports correlating the development of cutaneous meningioma to high-grade convexity meningioma. CASE DESCRIPTION: A 63-year-old man underwent total resection of a right frontal convexity meningioma, World Health Organization Grade I in 2001. He presented in 2016 with a small frontal cutaneous mass over the craniotomy site. Computed tomography showed extracranial and intracranial components of the meningioma. The patient declined surgical intervention and lost to follow. One and half years later, he underwent resection of the growing ulcerating cutaneous component in an outside hospital. The pathological diagnosis was Grade 3 meningioma. Six months later, he presented to us with a massive cutaneous meningioma and large intracranial component. Surgical resection and multidisciplinary management were planned. The patient was very hesitant to have surgery but settled for receiving radiation. Seven months after radiation, he presented with a decreased level of consciousness and skin necrosis with maggot infestation. His code status was changed to "do not attempt resuscitation," and he died 3 days later in December 2019. CONCLUSION: Large intracranial meningiomas with massive transosseous extension to the scalp pose a significant challenge to the treating team. Proper planning and a multidisciplinary approach are essential. However, prognosis remains generally poor.
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INTRODUCTION: Rathke's cleft cysts (RCCs) are benign cystic lesions from the remnant cells of the craniopharyngeal duct within Rathke's pouch. Anticipation of such condition will help planning the treatment course. PRESENTATION OF CASE: We present a case of a 46-year-old male, referred to our tertiary center with a history of seizures, confusion and agitation for the past two weeks. After thorough investigations, he was found to have hyponatremia with low serum cortisol and hypothyroidism. After being sedated, intubated and stabilized, Magnetic Resonance Imaging (MRI) brain showed relatively medium to large sellar lesion which was highly suspicious of a craniopharyngioma (CP). However, after performing an endoscopic transphenoidal surgical resection of the lesion, clinical diagnosis supported RCC. DISCUSSION: The best treatment approach for CP is a complete surgical resection via a transphenoidal approach. Considering the fluid component of RCC, it may be treated with a more conservative surgery and does not necessitate a surgery as invasive as that of CP. CONCLUSION: Given the mixed solid and cystic nature of CPs, it is possible to confuse it with RCC and vice versa. The presented case highlights that Rathke's cyst may be challenging in terms of pre-operative diagnosis, peri-surgical management and histopathological examination.
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Although meningiomas represent the most common class of tumors of the central nervous system, the molecular events underlying their genesis and development are still not well defined, and therapeutic approaches based on the genetics of these tumors are currently lacking. In the present study we have used the immunoblotting technique to show that the p16(INK4A), Cdk6 and pRB proteins are differentially expressed in primary meningioma cells with 20-, 30- and 36-fold difference between the lowest and the highest levels of each protein, respectively. In addition, we present evidence that the level of the anti-apoptosis survivin protein is high in these benign tumors. Moreover, the annexin V-associated flow cytometry technique was used to show that 60% of meningioma cell cultures underwent apoptosis in response to both gamma-rays and cisplatin, and 50% of these cells exhibited significant sensitivity to hydroxyurea. These agents triggered apoptosis through the mitochondrial pathway, by increasing the Bax/Bcl-2 ratio. Interestingly, the induction of apoptosis following radiation and cisplatin was significant in all cells that expressed low levels of p16(INK4A), Cdk6 and pRB proteins. These data shed more light on the molecular biology of meningioma cells and suggest that survivin and proteins of the RB pathway could play a determinant role in the development and the treatment of meningiomas.
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Apoptose/fisiologia , Quinase 6 Dependente de Ciclina/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína do Retinoblastoma/metabolismo , Adolescente , Adulto , Idoso , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Quinase 6 Dependente de Ciclina/efeitos dos fármacos , Quinase 6 Dependente de Ciclina/efeitos da radiação , Inibidor p16 de Quinase Dependente de Ciclina/efeitos dos fármacos , Inibidor p16 de Quinase Dependente de Ciclina/efeitos da radiação , Feminino , Citometria de Fluxo , Humanos , Hidroxiureia/farmacologia , Immunoblotting , Proteínas Inibidoras de Apoptose , Masculino , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias Meníngeas/radioterapia , Meningioma/tratamento farmacológico , Meningioma/radioterapia , Proteínas Associadas aos Microtúbulos/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/efeitos da radiação , Pessoa de Meia-Idade , Proteínas de Neoplasias/efeitos dos fármacos , Proteínas de Neoplasias/efeitos da radiação , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/efeitos da radiação , Radioterapia , Proteína do Retinoblastoma/efeitos dos fármacos , Proteína do Retinoblastoma/efeitos da radiação , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Survivina , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , Regulação para Cima/efeitos da radiação , Proteína X Associada a bcl-2/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/efeitos da radiaçãoRESUMO
We describe a pediatric case of primary angiosarcoma of the brain displaying striking intravascular papillary pattern, consistent with the "Dabska tumor," often in continuity with a massive, multifocal intravascular papillary endothelial hyperplasia. The tumor contained small hemangioma and obliterated dysplastic arteries as well as very large thin-walled veins. The surrounding brain tissue showed scattered telangiectasias, conglomerates of calcified dysplastic arteries, old hemorrhages and gliosis. Colocalization of these lesions suggests the development of a papillary angiosarcoma in the pre-existing vascular malformation. Although never reported, the possibility of a malignant transformation of endothelial papillary hyperplasia also should be considered in this case.
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Neoplasias Encefálicas , Hemangiossarcoma , Neoplasias de Tecido Vascular , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Criança , Craniotomia , Evolução Fatal , Hemangiossarcoma/diagnóstico por imagem , Hemangiossarcoma/patologia , Hemangiossarcoma/cirurgia , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Masculino , Metástase Neoplásica , Neoplasias de Tecido Vascular/diagnóstico por imagem , Neoplasias de Tecido Vascular/patologia , Neoplasias de Tecido Vascular/cirurgia , RadiografiaRESUMO
BACKGROUND AND OBJECTIVES: Ependymoma is the most frequently encountered intramedullary tumor. Total surgical resection is the therapeutic modality of choice whenever possible, but carries a significant risk of morbidity. This study was designed to define prognostic factors that affect clinical outcome after surgical resection of spinal intramedullary ependymoma. PATIENTS AND METHODS: The medical records, radiological and pathological studies of all patients with intramedullary spinal ependymomas treated surgically in one institution were reviewed retrospectively. Spinal myxopapillary ependymomas were excluded. In a multivariable regression analysis, possible prognostic factors were correlated with the 6-month postoperative neurological status using McCormick's grading scale. RESULTS: Surgery was performed on 17 patients (14 males, 3 females, mean age of 42+/-15 years) with spinal ependymoma. The cervical spine was the most common tumor location (71%). Total surgical resection of the tumor was achieved in 11 cases (65%). Intraoperative neurophysiological monitoring was used in 8 cases (47%). Postoperatively, 11 patients (65%) either improved or had no change from their preoperative neurological status. None of the 11 totally resected tumors has shown evidence of recurrence in a follow-up period range from 8-120 months (median, 33 months). Of several possible prognostic factors, the only statistically significant correlation identified with the 6-month postoperative neurological status was the preoperative McCormick grading score. CONCLUSIONS: Preoperative neurological status was the only statistically significant factor in determining the postoperative neurological outcome of patients with spinal intramedullary ependymomas. Early diagnosis and referral for surgery to specialized centers are recommended as controllable factors in improving outcome.
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Ependimoma/cirurgia , Neoplasias da Medula Espinal/cirurgia , Adulto , Idoso , Ependimoma/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Recidiva Local de Neoplasia/epidemiologia , Exame Neurológico , Prognóstico , Análise de Regressão , Estudos Retrospectivos , Neoplasias da Medula Espinal/diagnóstico , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the diagnostic yield, accuracy, and safety of frame-based stereotactic brain biopsy procedures. METHODS: A retrospective study of all pathologically diagnosed intracranial lesions, using frame-based stereotactic guided brain biopsy procedures performed at King Faisal Specialist Hospital and Research Centre (KFSH&RC), Riyadh, Kingdom of Saudi Arabia between 1993 and 2005 was conducted. Medical charts, radiological studies, and pathological slides were reviewed. RESULTS: A total of 120 consecutive patients who had frame-based stereotactic diagnostic biopsy procedures were identified. Data regarding procedural techniques, lesion locations, pathological diagnosis, and postoperative complications were collected. Patients` ages ranged from 3-72 years (mean +/- standard deviation: 39.4 +/- 20.3), 67 males and 53 females. Sites of biopsied lesions included: 49 thalamic, 29 deep frontal, 23 parietal, 9 temporal, and 10 others. Targeting accuracy was 99.2%. General anesthesia was used in 103 patients (85.8%). The rest was carried out under local anesthesia. Diagnostic yield was estimated at 96%. Most frequently encountered pathological diagnosis includes gliomas (63%), infections (16%), and lymphomas (7%). One mortality (0.8%), and 5 (4%) morbidities were encountered. CONCLUSION: Stereotactic brain biopsy is a relatively safe technique to obtain a tissue biopsy that represents the pathology of the lesion. Recent advances in stereotactic neurosurgical techniques have helped to improve the safety and diagnostic yield of such procedures.
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OBJECTIVE: To determine optimal interstimulus interval (ISI) and pulse duration (D) for direct cortical stimulation (DCS) motor evoked potentials (MEPs) based on rheobase and chronaxie derived with two techniques. METHODS: In 20 patients under propofol/remifentanil anesthesia, 5-pulse DCS thenar MEP rheobase and chronaxie with 2, 3, 4 and 5ms ISI were measured by linear regression of five charge thresholds at 0.05, 0.1, 0.2, 0.5 and 1msD, and estimated from two charge thresholds at 0.1 and 1msD using simple arithmetic. Optimal parameters were defined by minimum threshold energy: the ISI with lowest rheobase2×chronaxie, and D at its chronaxie. Near-optimal was defined as threshold energy <25% above minimum. RESULTS: The optimal ISI was 3 or 4 (n=7 each), 2 (n=4), or 5ms (n=2), but only 4ms was always either optimal or near-optimal. The optimal D was â¼0.2 (n=12), â¼0.1 (n=7) or â¼0.3ms (n=1). Two-point estimates closely approximated five-point measurements. CONCLUSIONS: Optimal ISI/D varies, with 4ms/0.2ms being most consistently optimal or near-optimal. Two-point estimation is sufficiently accurate. SIGNIFICANCE: The results endorse 4ms ISI and 0.2msD for general use. Two-point estimation could enable quick individual optimization.
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Cronaxia/fisiologia , Estimulação Elétrica/métodos , Potencial Evocado Motor/fisiologia , Monitorização Intraoperatória/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto JovemRESUMO
OBJECTIVE: To address the limitations of standard electromyography (EMG) facial nerve monitoring techniques by exploring the novel application of multi-pulse transcranial electrical stimulation (mpTES) to myogenic facial motor evoked potential (MEP) monitoring. METHODS: In 76 patients undergoing skull base surgery, mpTES was delivered through electrodes 1cm anterior to C1 and C2 (M1-M2), C3 and C4 (M3-M4) or C3 or C4 and Cz (M3/M4-Mz), with the anode contralateral to the operative side. Facial MEPs were monitored from the orbicularis oris muscle on the operative side. Distal facial nerve excitation was excluded by the absence of single pulse responses and by onset latency consistent with a central origin. RESULTS: M3/M4-Mz mpTES (n=50) reliably produced facial MEPs while M1-M2 (n=18) or M3-M4 (n=8) stimulation produced 6 technical failures. Facial MEPs could be successfully monitored in 21 of 22 patients whose proximal facial nerves were inaccessible to direct stimulation. Using 50, 35 and 0% of baseline amplitude criteria, significant facial deficits were predicted with a sensitivity/specificity of 1.00/0.88, 0.91/0.97 and 0.64/1.00, respectively. CONCLUSIONS: Facial MEPs can provide an ongoing surgeon-independent assessment of facial nerve function and predict facial nerve outcome with sufficiently useful accuracy. SIGNIFICANCE: This method substantially improves facial nerve monitoring during skull base surgery.
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Neoplasias Encefálicas/fisiopatologia , Potencial Evocado Motor/fisiologia , Nervo Facial/fisiopatologia , Monitorização Intraoperatória , Base do Crânio/fisiopatologia , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/terapia , Pré-Escolar , Estimulação Elétrica/métodos , Eletromiografia/métodos , Potencial Evocado Motor/efeitos da radiação , Nervo Facial/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Tempo de Reação/efeitos da radiaçãoRESUMO
PURPOSE: Gliomas of the optic pathways are rare childhood central nervous system tumors. The treatment approach is controversial because of its rarity and the slow and unpredictable growth rates of these lesions. METHODS AND MATERIALS: We reviewed 50 patients with the diagnosis of optic pathway low-grade gliomas treated between January 1980 and December 1995 at King Faisal Specialist Hospital and Research Center, Saudi Arabia. Thirty-five patients presented with chiasmatic/hypothalamic (posterior tumors), and 15 with optic nerve gliomas with or without chiasmal involvement (anterior tumors). Evidence of neurofibromatosis was present in 18 patients. Twenty-nine patients underwent surgery (total or partial resection), and 12 of these received postoperative radiotherapy (RT). Sixteen patients were treated with primary RT. The radiation dose varied between 42 and 54 Gy (median dose 50). RESULTS: The overall actuarial survival rate was 87.5% at 5 years and 75% at 10 years, and the corresponding progression-free survival (PFS) rates were 69% and 62%. Patients with anterior tumors fared better than those with posterior tumors, with a 10-year PFS rate of 72% and 58%, respectively; the difference, however, was not statistically significant (p = 0.58). A PFS advantage was found in favor of patients with posterior tumors treated with RT (primary or postoperative) compared with no RT, with 5-year PFS rates of 68% vs. 42% (p = 0.03). This, however, did not translate into a survival advantage because of the success of salvage treatment. CONCLUSION: In multivariate analysis, age (<3 vs. >3 years) emerged as the only significant determinant for PFS with patients <3 years old faring worse (p = 0.03). Neurologic and endocrine dysfunction are significant problems that need to be addressed.
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Glioma do Nervo Óptico/mortalidade , Glioma do Nervo Óptico/terapia , Adolescente , Adulto , Análise de Variância , Criança , Pré-Escolar , Terapia Combinada , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Visão OcularRESUMO
BACKGROUND AND OBJECTIVES: Intracranial germ cell tumors (GCTs) are not a common disease. We reviewed the experience of a single institution to determine the variables that affect treatment outcome. DESIGN AND SETTING: A retrospective review of patients with the diagnosis of intracranial germ cell tumors treated in a single institution (KFSHRC) during the period from March 1985 to December 2007. PATIENTS AND METHODS: Fifty-seven patients with the diagnosis of intracranial GCT were recorded in the KFSHRC Tumor Registry during the period from 1985 to 2007. Seven patients with a pineal region tumor treated as germinomas in the earlier years without a tissue diagnosis were excluded. This retrospective study was restricted to the remaining 50 patients with a tissue or marker diagnosis: 31 germinomas and 19 non-germinomatous germ cell tumors (NGGCTs). RESULTS: The 10-year overall survival (OS), event-free survival (EFS) and relapse-free survival (RFS) were 87%, 88% and 96% for patients with germinoma, with a median follow-up of 4.5 (range 2-17) years, compared with 26%, 29% and 46% for patients with NGGCT with a median follow-up of 3 (range 1.5-13) years. For NGGCT, variables favorably influencing OS were younger age (< 16 y vs ≥16 y, P=.01), higher radiation dose (>50 Gy vs ≤50 Gy; P=.03) and later year of diagnosis (>1990 vs <1990 P=.002). CONCLUSIONS: Tissue diagnosis of GCTs is mandatory prior to treatment except for patients with elevated markers. In germinoma, localized radiotherapy (RT) for M0 patients may be adequate. Long-term follow-up is needed to define the benefit of adding chemotherapy. For NGGCT, the use of combined modality treatment and RT dose ;gt;50 Gy are important factors that influence the outcome. Second-look surgery and resection of residual/ refractory tumors is always recommended.
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Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/terapia , Neoplasias Embrionárias de Células Germinativas/terapia , Adolescente , Adulto , Fatores Etários , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Recidiva Local de Neoplasia , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/patologia , Doses de Radiação , Estudos Retrospectivos , Arábia Saudita , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto JovemAssuntos
Doenças do Nervo Óptico/diagnóstico , Pinealoma/diagnóstico , Adulto , Encéfalo/patologia , Meios de Contraste/química , Progressão da Doença , Fundo de Olho , Marcha , Humanos , Hidrocefalia/complicações , Hidrocefalia/diagnóstico , Pressão Intracraniana , Imageamento por Ressonância Magnética , Masculino , Atrofia Óptica , Doenças do Nervo Óptico/complicações , Papiledema/complicações , Papiledema/diagnóstico , Pinealoma/complicaçõesRESUMO
Survivin, an inhibitor of apoptosis, is over-expressed in foetal tissues and human cancers, but it is almost undetectable in normal tissues. Here we have assessed the level of the survivin protein in some benign tumors of the nervous system: meningioma, schwannoma, low-grade ependymoma, pilocytic astrocytoma and pituitary adenoma. Using immuno-blot analysis we present evidence that these low-grade tumors are positive for survivin expression. In agreement, flow cytometrical analysis showed that both spontaneous and radiation-induced apoptosis levels are very low in these neoplasms. Using host cell reactivation assay we have also shown that these tumor cells are proficient in the repair of gamma-ray-induced DNA damage. However, they are deficient in the removal of ultraviolet (UV) light-induced DNA photolesions, especially the shwannoma- and the pituitary adenoma-derived cells. These results suggest that survivin overexpression may be an early event in the stepwise tumoregenesis and hence could be responsible for the onset as well as the growth advantage during tumoregenic progression of malignant as well as benign neoplasms.
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Apoptose/fisiologia , Apoptose/efeitos da radiação , Proteínas Associadas aos Microtúbulos/biossíntese , Neoplasias do Sistema Nervoso/metabolismo , Neoplasias do Sistema Nervoso/patologia , Linhagem Celular Tumoral , Dano ao DNA/efeitos da radiação , Eletroforese em Gel de Poliacrilamida , Citometria de Fluxo , Raios gama , Genes p53/genética , Genes p53/efeitos da radiação , Humanos , Immunoblotting , Proteínas Inibidoras de Apoptose , Proteínas de Neoplasias/metabolismo , Proteína Oncogênica p21(ras)/biossíntese , Proteína Oncogênica p21(ras)/efeitos da radiação , Survivina , Células Tumorais Cultivadas , Raios UltravioletaRESUMO
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