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1.
J Endocrinol Invest ; 44(12): 2621-2633, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33847973

RESUMO

CONTEXT: Although consensus guidelines recommend dopamine agonists (DAs) as the first-line approach in prolactinomas, some patients may opt instead for upfront surgery, with the goal of minimizing the need for continuation of DAs over the long term. While this approach can be recommended in selected patients with a microprolactinoma, the indication for upfront surgery in macroprolactinomas remains controversial, with limited long-term data in large cohorts. We aimed at elucidating whether first-line surgery is equally safe and effective for patients with micro- or macroprolactinomas not extending beyond the median carotid line (i.e., Knosp grade ≤ 1). METHODOLOGY: Retrospective study of patients with prolactinomas Knosp grade ≤ 1 treated with upfront surgery. The primary endpoint was patients' dependence on DAs at last follow-up. The secondary endpoint was postoperative complications. Independent risk factors for long-term dependence on DAs were analyzed. RESULTS: A microadenoma was noted in 45 patients (52%) and a macroadenoma in 41 (48%), with 17 (20%) harboring a Knosp grade 1 prolactinoma. Median follow-up was 80 months. First-line surgery resulted in long-term remission in 31 patients (72%) with a microprolactinoma and in 18 patients (45%) with a macroprolactinoma (p = 0.02). DA therapy was ultimately required in 11 patients (24%) with microadenomas vs. 20 (49%) with macroadenomas (p = 0.03). As for the latter, DA was required in 13 patients (76%) with Knosp grade 1 macroadenomas vs. 7 patients (29%) with Knosp grade 0 macroadenomas (p = 0.004). There was no mortality, and morbidity was minimal. Knosp grade 1 prolactinomas (OR 7.3, 95% CI 1.4-37.7, p = 0.02) but not adenoma size (i.e., macroprolactinomas) were an independent predictor of long-term dependence on DAs. CONCLUSIONS: First-line surgery in patients with microprolactinomas or macroprolactinomas Knosp grade 0 resulted in a good chance of non-dependency on DA therapy. However, in patients with prolactinomas Knosp grade 1, first-line surgery cannot be recommended, as adjuvant DA therapy after surgery is required in the majority of them over the long term.


Assuntos
Agonistas de Dopamina , Hipofisectomia , Invasividade Neoplásica/diagnóstico , Neoplasias Hipofisárias , Complicações Pós-Operatórias , Prolactinoma , Seio Cavernoso/patologia , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/efeitos adversos , Duração da Terapia , Feminino , Humanos , Hipofisectomia/efeitos adversos , Hipofisectomia/métodos , Hipofisectomia/estatística & dados numéricos , Imuno-Histoquímica , Efeitos Adversos de Longa Duração/diagnóstico , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/prevenção & controle , Prolactinoma/tratamento farmacológico , Prolactinoma/patologia , Prolactinoma/cirurgia , Risco Ajustado/métodos , Carga Tumoral
2.
Clin Neuropathol ; 28(2): 83-90, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19353838

RESUMO

OBJECTIVE: A case of Lhermitte-Duclos disease (LDD, dysplastic gangliocytoma) with atypical vascularization is reported. LDD is a rare cerebellar mass lesion which may be associated with Cowden's syndrome and the PTEN germline mutation. CASE MATERIAL: A 61-year-old male presented 15 years before with a transient episode of unspecific gait disturbance. Initial magnetic resonance (MR) imaging revealed a right-sided, diffuse, nonenhancing cerebellar mass lesion. No definitive diagnosis was made at that time, and the symptoms resolved spontaneously. 15 years later, the patient presented with acute onset of vomiting associated with headache and ataxic gait. MR imaging showed a progression of the lesion with occlusive hydrocephalus. The lesion depicted a striated pattern characteristic for LDD with T1-hypointense and T2-hyperintense bands, nonenhancing with contrast. After resection of the mass lesion, the cerebellar and hydrocephalic symptoms improved rapidly. The pathological examination confirmed the diagnosis of dysplastic gangliocytoma (WHO Grade I) with enlarged granular and molecular cell layers, reactive gliosis and dysplastic blood vessels. No other clinical features associated with Cowden's syndrome were present. CONCLUSIONS: This case illustrates that LDD with atypical vascularization is a slow-growing posterior fossa mass lesion which may remain asymptomatic for many years. Timing of surgical treatment and extent of resection in patients with LDD is controversial. The typical features on standard T1-/T2-weighted MR imaging allow a diagnosis without surgery in most cases. The authors believe that the decision to treat in these cases should be based on clinical deterioration.


Assuntos
Neoplasias Cerebelares/patologia , Cerebelo/patologia , Síndrome do Hamartoma Múltiplo/patologia , Neoplasias Cerebelares/irrigação sanguínea , Neoplasias Cerebelares/fisiopatologia , Cerebelo/irrigação sanguínea , Cerebelo/fisiopatologia , Progressão da Doença , Síndrome do Hamartoma Múltiplo/complicações , Síndrome do Hamartoma Múltiplo/fisiopatologia , Síndrome do Hamartoma Múltiplo/cirurgia , Humanos , Hidrocefalia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
3.
J Neuroradiol ; 35(4): 224-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18420272

RESUMO

OBJECTIVES: Diffusion-weighted MRI is sensitive to molecular motion and has been applied to the diagnosis of stroke. Our intention was to investigate its usefulness in patients with brain tumor and, in particular, in the perilesional edema. METHODS: We performed MRI of the brain, including diffusion-weighted imaging and mapping of the apparent diffusion coefficient (ADC), in 16 patients with brain tumors (glioblastomas, low-grade gliomas and metastases). ADC values were determined by the use of regions of interest positioned in areas of high signal intensities as seen on T2-weighted images and ADC maps. Measurements were taken in the tumor itself, in the area of perilesional edema and in the healthy contralateral brain. RESULTS: ADC mapping showed higher values of peritumoral edema in patients with glioblastoma (1.75 x 10(-3)mm(2)/s) and metastatic lesions (1.61 x 10(-3)mm(2)/s) compared with those who had low-grade glioma (1.40 x10(-3)mm(2)/s). The higher ADC values in the peritumoral zone were associated with lower ADC values in the tumor itself. CONCLUSIONS: The higher ADC values in the more malignant tumors probably reflect vasogenic edema, thereby allowing their differentiation from other lesions.


Assuntos
Neoplasias Encefálicas/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Edema Encefálico/patologia , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
Acta Neurochir (Wien) ; 148(12): 1257-65; discussion 1266, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17086473

RESUMO

BACKGROUND: The management of patients with small, often asymptomatic meningiomas is controversial and includes observation, microsurgery (MS) and stereotactic radiosurgery (SRS). The purpose of this retrospective study was to analyze the morbidity and the extent of removal after MS for small (< or =3 cm) intracranial meningiomas and compare these results to those of SRS reported in the literature. METHODS: All patients with an intracranial meningioma with a maximum diameter up to 3 cm operated on in our institution over a 10 year period (1992-2002) were included in the study and retrospectively analyzed. Patients were grouped into asymptomatic and symptomatic and according to tumor location as: group I (cranial vault, parasagittal, lateral sphenoid), group II (falx, frontobasal, medial sphenoid, parasellar and tentorial), group III (cavernous sinus, petroclival, petrosal, CPA and foramen magnum). FINDINGS: There were a total of 201 patients, of whom 102 were asymptomatic and 99 were symptomatic. The overall risk of permanent neurological morbidity was 4.9% in asymptomatic and 23.2% in symptomatic patients. The combined risk in asymptomatic and symptomatic patients was 5.4% in group I, 11.5% in group II, and 39.9% in group III lesions. Radical removal was achieved in all patients in group I, in 93.7% of group II, and 80% of group III lesions. There was no disease related mortality. CONCLUSIONS: MS provides excellent efficacy and morbidity results in groups I and II meningiomas, especially in asymptomatic patients and might therefore be considered the first choice of treatment for these patients. The results of MS in group III were worse than those of SRS reported in the literature.


Assuntos
Dura-Máter/cirurgia , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Microcirurgia/estatística & dados numéricos , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Neoplasias da Base do Crânio/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Dura-Máter/patologia , Dura-Máter/fisiopatologia , Feminino , Humanos , Masculino , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/fisiopatologia , Meningioma/patologia , Meningioma/fisiopatologia , Microcirurgia/efeitos adversos , Microcirurgia/métodos , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Retrospectivos , Medição de Risco , Crânio/patologia , Crânio/fisiopatologia , Crânio/cirurgia , Base do Crânio/patologia , Base do Crânio/fisiopatologia , Base do Crânio/cirurgia , Neoplasias da Base do Crânio/patologia , Neoplasias da Base do Crânio/fisiopatologia , Resultado do Tratamento
5.
Acta Neurochir Suppl ; 94: 153-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16060257

RESUMO

The purpose of this study was to analyze the suitability of the cerebral vasculature of the pig regarding a revascularization procedure. In two 60 kg pigs the femoral artery was exposed and canulated for selective angiography and interventional procedures. After the angiography, the pigs were brought to the animal OR for craniotomy and analysis of the intracranial cerebral arteries and the surgical exposure of the carotid arteries under the microscope. Angiography demonstrated the presence of a true internal-, external carotid artery and vertebral arteries. Both the vertebral and internal carotid arteries are feeding a rete mirabilis both at the cranial base and the cranio-cervical junction. At these sites further advancement of the angiography catheter was not possible. Out of these rete mirabilis, an intracranial carotid artery and an intracranial vertebral artery were formed, respectively. The intracranial cerebral vessels were of the dimension of 1 mm and less. The extracranial portion of the internal carotid artery was 2.5 mm of diameter. From these findings, we conclude that a direct cerebral revascularization procedure of the intracranial vessels is not possible in the swine. However, a global revascularization procedure on the extracranial portion of the internal carotid artery is thus feasible, both using a low- and high-flow anastamosis technique.


Assuntos
Encéfalo/irrigação sanguínea , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/cirurgia , Revascularização Cerebral/métodos , Modelos Animais , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/cirurgia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Estudos de Viabilidade , Radiografia , Suínos
6.
J Neurochem ; 95(1): 33-45, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16045451

RESUMO

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder, characterized by a prominent loss of GABA-ergic medium-sized spiny neurons in the caudate putamen. There is evidence that impaired energy metabolism contributes to neuronal death in HD. Creatine is an endogenous substrate for creatine kinases and thereby supports cellular ATP levels. This study investigated the effects of creatine supplementation (5 mm) on cell survival and neuronal differentiation in striatal cultures. Chronic creatine treatment resulted in significant increased densities of GABA-immunoreactive (-ir) neurons, although total neuronal cell number and general viability were not affected. Similar effects were seen after short-term treatment, suggesting that creatine acted as a differentiation factor. Inhibitors of transcription or translation did not abolish the creatine-mediated effects, nor did omission of extracellular calcium, whereas inhibition of mitogen-activated protein kinase and phosphatidylinositol-3-kinase significantly attenuated the creatine induced increase in GABA-ir cell densities. Creatine exhibited significant neuroprotection against toxicity instigated either by glucose- and serum deprivation or addition of 3-nitropropionic acid. In sum, the neuroprotective properties in combination with promotion of neuronal differentiation suggest that creatine has potential as a therapeutic drug in the treatment of neurodegenerative diseases, like HD.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Corpo Estriado/citologia , Corpo Estriado/metabolismo , Creatina/farmacologia , Neurônios/citologia , Neurônios/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Creatina/administração & dosagem , Creatina Quinase/metabolismo , Meios de Cultura Livres de Soro/farmacologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Glucose/deficiência , Isoenzimas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurotoxinas/farmacologia , Nitrocompostos , Fosfatidilinositol 3-Quinases/metabolismo , Propionatos/farmacologia , Ratos , Ratos Wistar , Células-Tronco/citologia , Células-Tronco/metabolismo , Distribuição Tecidual
7.
Neuroscience ; 133(3): 701-13, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15890457

RESUMO

Parkinson's disease is a disabling neurodegenerative disorder of unknown etiology characterized by a predominant and progressive loss of dopaminergic neurons in the substantia nigra. Recent findings suggest that impaired energy metabolism plays an important role in the pathogenesis of this disorder. The endogenously occurring guanidino compound creatine is a substrate for mitochondrial and cytosolic creatine kinases. Creatine supplementation improves the function of the creatine kinase/phosphocreatine system by increasing cellular creatine and phosphocreatine levels and the rate of ATP resynthesis. In addition, mitochondrial creatine kinase together with high cytoplasmic creatine levels inhibit mitochondrial permeability transition, a major step in early apoptosis. In the present study, we analyzed the effects of externally added creatine on the survival and morphology of dopaminergic neurons and also addressed its neuroprotective properties in primary cultures of E14 rat ventral mesencephalon. Chronic administration of creatine [5 mM] for 7 days significantly increased survival (by 1.32-fold) and soma size (by 1.12-fold) of dopaminergic neurons, while having no effect on other investigated morphological parameters. Most importantly, concurrent creatine exerted significant neuroprotection for dopaminergic neurons against neurotoxic insults induced by serum and glucose deprivation (P < 0.01), 1-methyl-4-phenyl pyridinium ion (MPP+) [15 microM] and 6-hydroxydopamine (6-OHDA) [90 microM] exposure (P < 0.01). In addition, creatine treatment significantly protected dopaminergic cells facing MPP+-induced deterioration of neuronal morphology including overall process length/neuron (by 60%), number of branching points/neuron (by 80%) and area of influence per individual neuron (by 60%). Less pronounced effects on overall process length/neuron and number of branching points/neuron were also found after 6-OHDA exposure (P < 0.05) and serum/glucose deprivation (P < 0.05). In conclusion, our findings identify creatine as a rather potent natural survival- and neuroprotective factor for developing nigral dopaminergic neurons, which is of relevance for therapeutic approaches in Parkinson's disease and for the improvement of cell replacement strategies.


Assuntos
Creatina/farmacologia , Dopamina/fisiologia , Mesencéfalo/citologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , 1-Metil-4-fenilpiridínio/farmacologia , Animais , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Creatina Quinase/metabolismo , Creatina Quinase Forma BB , Creatina Quinase Mitocondrial , Creatinina/metabolismo , Interações Medicamentosas , Feminino , Isoenzimas/metabolismo , Neurônios/metabolismo , Oxidopamina/farmacologia , Gravidez , Ratos , Ratos Sprague-Dawley , Simpatolíticos/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo
8.
Acta Neurochir (Wien) ; 146(5): 441-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15118879

RESUMO

BACKGROUND: The study was performed to elucidate the impact of tumour volume and surgical resection on the long-term outcome of patients with supratentorial, diffuse, World Health Organization (WHO) grade II astrocytomas and oligo-astrocytomas. METHOD: After analysing 79 adult patients consecutively diagnosed between 1991 and 2000, we selected a group of 42 patients treated by surgery without adjuvant therapy. The tumour volume was defined as the whole region of T2-hyperintensity and measured interactively on pre- and postoperative and follow-up Magnetic Resonance Imaging (MRI) using a dedicated imaging software. Volumetric, clinical, and histological data were analysed for correlation with tumour progression (TP), malignant transformation (MT), drop in functional status (DKPS) and overall survival (OS). FINDINGS: Pre- and postoperative tumour volumes, and the involvement of more than one lobe were strongly associated with worse outcome. Preoperative tumour volume was the strongest predictor of OS (p<0.01) and the only predictor of MT (p<0.05). The absolute and relative volumes of tumour removed by surgery were not significantly associated with outcome. CONCLUSIONS. Initial tumour volume, measured as the volume of T2-hyperintensity on MRI, and tumour extension are the strongest predictors of outcome in patients with supratentorial diffuse astrocytic WHO Grade II tumours. The potential benefit of aggressive tumour resection needs to be investigated in a prospective controlled trial.


Assuntos
Astrocitoma/patologia , Astrocitoma/cirurgia , Neoplasias Supratentoriais/patologia , Neoplasias Supratentoriais/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Processos Neoplásicos , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
9.
Acta Neurochir (Wien) ; 145(5): 341-9; discussion 349-50, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12820040

RESUMO

OBJECTIVE: The purpose of the study was to measure the effects of increased inspired oxygen on patients suffering severe head injury and consequent influences on the correlations between CPP and brain tissue oxygen (PtiO2) and the effects on brain microdialysate glucose and lactate. METHODS: In a prospective, observational study 20 patients suffering severe head injury (GCS< or =8) were studied between January 2000 and December 2001. Each patient received an intraparenchymal ICP device and an oxygen sensor and, in 17 patients brain microdialysis was performed at the cortical-subcortical junction. A 6 h 100% oxygen challenge (F IO2 1.0) ( Period A) was performed as early as possible in the first 24 hours after injury and compared with a similar 6 hour period following the challenge ( Period B). Statistics were performed using the linear correlation analysis, one sample t-test, as well as the Lorentzian peak correlation analysis. RESULTS: F IO2 was positively correlated with PtiO2 (p < 0.0001) over the whole study period. PtiO2 was significantly higher (p < 0.001) during Period A compared to Period B. CPP was positively correlated with PtiO2 (p < 0.001) during the whole study. PtiO2 peaked at a CPP value of 78 mmHg performing a Lorentzian peak correlation analysis of all patients over the whole study. During Period A the brain microdialysate lactate was significantly lower (p = 0.015) compared with Period B. However the brain microdialysate glucose remained unchanged. CONCLUSION: PtiO2 is significantly positively correlated with F IO2, meaning that PtiO2 can be improved by the simple manipulation of increasing F IO2 and ABGAO2. PtiO2 is positively correlated with CPP, peaking at a CPP value of 78 mmHg. Brain microdialysate lactate can be lowered by increasing PtiO2 values, as observed during the oxygen challenge, whereas microdialysate glucose is unchanged during this procedure. Extension of the oxygen challenge time and measurement of the intermediate energy metabolite pyruvate may clarify the metabolic effects of the intervention. Prospective comparative studies, including analysis of outcome on a larger multicenter basis, are necessary to assess the long term clinical benefits of this procedure.


Assuntos
Encéfalo/metabolismo , Traumatismos Craniocerebrais/metabolismo , Inalação , Consumo de Oxigênio , Oxigênio/metabolismo , Adolescente , Adulto , Idoso , Pressão Sanguínea , Dióxido de Carbono , Circulação Cerebrovascular , Traumatismos Craniocerebrais/fisiopatologia , Feminino , Glucose/metabolismo , Humanos , Ácido Láctico/metabolismo , Masculino , Microdiálise , Pessoa de Meia-Idade , Oxigênio/sangue , Pressão Parcial , Respiração , Volume de Ventilação Pulmonar , Fatores de Tempo , Índices de Gravidade do Trauma
10.
Neuroscience ; 108(2): 273-84, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11734360

RESUMO

Transplantation of embryonic dopaminergic neurons is an experimental therapy for Parkinson's disease, but limited tissue availability and suboptimal survival of grafted dopaminergic neurons impede more widespread clinical application. Glial cell line-derived neurotrophic factor (GDNF) and neurotrophin-4/5 (NT-4/5) exert neurotrophic effects on dopaminergic neurons via different receptor systems. In this study, we investigated possible additive or synergistic effects of combined GDNF and NT-4/5 treatment on rat embryonic (embryonic day 14) nigral explant cultures grown for 8 days. Contrary to cultures treated with GDNF alone, cultures exposed to NT-4/5 and GDNF+NT-4/5 were significantly larger than controls (1.6- and 2.0-fold, respectively) and contained significantly more protein (1.6-fold). Treatment with GDNF, NT-4/5 and GDNF+NT-4/5 significantly increased dopamine levels in the culture medium by 1.5-, 2.5- and 4.7-fold, respectively, compared to control levels, and the numbers of surviving tyrosine hydroxylase-immunoreactive neurons increased by 1.7-, 2.1-, and 3.4-fold, respectively. Tyrosine hydroxylase enzyme activity was moderately increased in all treatment groups compared to controls. Counts of nigral neurons containing the calcium-binding protein, calbindin-D28k, revealed a marked increase in these cells by combined GDNF and NT-4/5 treatment. Western blots for neuron-specific enolase suggested an enhanced neuronal content in cultures after combination treatment, whereas the expression of glial markers was unaffected. The release of lactate dehydrogenase into the culture medium was significantly reduced for GDNF+NT-4/5-treated cultures only. These results indicate that combined treatment with GDNF and NT4/5 may be beneficial for embryonic nigral donor tissue either prior to, or in conjunction with, intrastriatal transplantation in Parkinson's disease.


Assuntos
Transplante de Tecido Encefálico/métodos , Sobrevivência de Enxerto/fisiologia , Neostriado/cirurgia , Fatores de Crescimento Neural/farmacologia , Proteínas do Tecido Nervoso/farmacologia , Neurônios/efeitos dos fármacos , Doença de Parkinson/cirurgia , Substância Negra/efeitos dos fármacos , Animais , Calbindina 1 , Calbindinas , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Dopamina/metabolismo , Interações Medicamentosas/fisiologia , Feminino , Feto , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Sobrevivência de Enxerto/efeitos dos fármacos , Imuno-Histoquímica , L-Lactato Desidrogenase/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neurônios/citologia , Neurônios/transplante , Fosfopiruvato Hidratase/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley , Proteína G de Ligação ao Cálcio S100/metabolismo , Transplante de Células-Tronco , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Substância Negra/citologia , Substância Negra/transplante , Tirosina 3-Mono-Oxigenase/metabolismo
13.
Clin Cancer Res ; 7(8): 2480-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11489830

RESUMO

PURPOSE: To discover the genetic determinants of glioma invasion in vivo, we compared the mRNA expression profiles of glioblastoma cells residing at the tumor core versus those at the invasive rim of a human tumor resection. EXPERIMENTAL DESIGN: From a single glioblastoma specimen, 20,000 individual cells from each region (core and invasive rim) were collected by laser capture microdissection and analyzed by mRNA differential display. Differential expression of gene candidates was confirmed by laser capture microdissection and quantitative reverse transcription-PCR in additional glioblastoma multiforme specimens, and the role in migration was further evaluated in glioma cell lines in vitro. RESULTS: Reproducible overexpression the death-associated Protein 3 (Dap-3) mRNA (NM 004632, GenBank; also reported as human ionizing resistance conferring protein mRNA, HSU18321, GenBank) by invasive cells was identified. Although the full-length Dap-3 protein has been described as proapoptotic, the NH(2)-terminal fragment can act in a dominant negative way resulting in protection from programmed cell death. In glioma cell lines T98G and G112 with an induced motility phenotype, Dap-3 was up-regulated at the mRNA and protein level as assessed by quantitative reverse transcription-PCR, cDNA microarray, and Western blot analysis. These cells showed an increased resistance to undergo camptothecin-induced apoptosis, which was overcome by effective Dap-3-antisense treatment. Antisense treatment also decreased the migration ability of T98G cells. CONCLUSIONS: Dap-3 is up-regulated in invasive glioblastoma multiforme cells in vivo and in glioma cells with an induced motility phenotype in vitro. When migration is activated, Dap-3 is up-regulated and cells become resistant to apoptosis. These findings suggest that Dap-3 confers apoptosis-resistance when migration behavior is engaged.


Assuntos
Movimento Celular , Glioblastoma/patologia , Proteínas/genética , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , DNA Antissenso/farmacologia , Relação Dose-Resposta a Droga , Matriz Extracelular/fisiologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Humanos , Imuno-Histoquímica , Laminina/farmacologia , Invasividade Neoplásica , Fenótipo , Proteínas/análise , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA , Proteínas Ribossômicas , Células Tumorais Cultivadas
14.
Cancer Res ; 61(10): 4190-6, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11358844

RESUMO

The mRNA expression profiles from glioblastoma cells residing at the tumor core and invasive rim of a human tumor resection were compared. From a single tumor specimen, 20,000 single cells from each region were collected by laser capture microdissection. Differential expression of 50-60 cDNA bands was detected. One of the sequences overexpressed by the invasive cells showed 99% homology to the P311 gene, the protein product of which is reported to localize at focal adhesions. Relative overexpression of P311 by invading glioblastoma cells compared with tumor core was confirmed by quantitative reverse transcription-PCR of six glioblastoma specimens after laser capture microdissection collection of rim and core cells. In vitro studies using antisense oligodeoxynucleotides and integrin activation confirmed the role of P311 in supporting migration of malignant glioma cells. Immunochemistry studies confirmed the presence of the P311 protein in tumor cells, particularly at the invasive edge of human glioblastoma specimens.


Assuntos
Glioblastoma/genética , Proteínas do Tecido Nervoso , Proteínas Oncogênicas/genética , Sequência de Aminoácidos , Movimento Celular/fisiologia , Dissecação , Perfilação da Expressão Gênica , Glioblastoma/patologia , Humanos , Lasers , Dados de Sequência Molecular , Invasividade Neoplásica , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Proteínas Oncogênicas/fisiologia , Oncogenes , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
15.
Exp Neurol ; 167(1): 148-57, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11161602

RESUMO

Embryonic midbrain can be maintained as free-floating roller tube cultures prior to grafting in experimental Parkinson's disease. We examined the influence of pregrafting culture time and pretreatment with brain-derived neurotrophic factor on graft survival and function. Cultures were prepared from solid pieces of embryonic (E14) rat ventral mesencephalon and maintained 4, 8, or 12 days in vitro with or without brain-derived neurotrophic factor (100 ng/ml) and grafted into the striatum of 6-hydroxydopamine-lesioned rats. Graft survival and function were evaluated by amphetamine-induced rotation behavior, number of tyrosine hydroxylase-immunoreactive neurons, striatal reinnervation, and graft volume. Rats receiving untreated tissue cultured for 4 or 8 days displayed no differences in graft quality, while grafts from 12-day-old cultures contained significantly fewer (P < 0.05) tyrosine hydroxylase-immunoreactive neurons (340 +/- 97, 267 +/- 92, and 62 +/- 19) and displayed a lower survival rate (9.6 +/- 2.7, 7.9 +/- 2.7, and 2.6 +/- 0.8% for 4, 8, and 12 days in vitro, respectively). Only rats grafted with 4- and 8-day-old cultures recovered significantly (P < 0.05) from lesion-induced rotations (69.4 +/- 18.6, 70.3 +/- 13.9, and 23.2 +/- 12.1% for 4, 8, and 12 days in vitro, respectively). Striatal reinnervation decreased with increasing culture time (P < 0.05). Pretreatment of the cultures with brain-derived neurotrophic factor affected only graft-induced fiber reinnervation, which was reduced even after short culture times. We therefore suggest that a storage period of 8 days is well suited to maintain embryonic rat ventral mesencephalon with the free-floating roller tube culture technique prior to transplantation. BDNF pretreatment as a new strategy to improve graft survival and function, however, was not effective.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Sobrevivência de Enxerto/efeitos dos fármacos , Mesencéfalo/transplante , Doença de Parkinson Secundária/cirurgia , Anfetamina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Transplante de Tecido Encefálico , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Corpo Estriado/enzimologia , Corpo Estriado/patologia , Corpo Estriado/cirurgia , Técnicas de Cultura/métodos , Modelos Animais de Doenças , Feminino , Transplante de Tecido Fetal , Mesencéfalo/embriologia , Fibras Nervosas/enzimologia , Neurônios/citologia , Neurônios/enzimologia , Neurônios/transplante , Oxidopamina , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/patologia , Ratos , Ratos Sprague-Dawley , Tirosina 3-Mono-Oxigenase/metabolismo
16.
Neurosurgery ; 48(2): 353-7; discussion 357-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11220379

RESUMO

OBJECTIVE: Intratumoral arteriovenous shunting in glioblastomas has been suspected but neither proven nor quantified. METHODS: Using a previously described technique of selective intra-arterial intratumoral injection of 99mTc-labeled microparticles (macroaggregated albumin), we measured the amount of radioactivity, by cerebral and pulmonary scintigraphy, in seven patients with malignant gliomas (six with glioblastomas and one with an anaplastic oligodendroglioma). The pulmonary shunt index was calculated as a percentage from the pulmonary/pulmonary plus cerebral radioactivity ratio. RESULTS: The results revealed a mean pulmonary shunt index of 67% (range, 47-89%), indicating that most of the microparticles injected into the tumor via the arterial route bypassed the tumor and reached the lungs. The measured arteriovenous shunting was greater when the injection was performed in an artery exclusively perfusing the tumor. CONCLUSION: Important intratumoral arteriovenous shunting exists in glioblastomas. The potential consequences of this finding for intra-arterial treatment strategies are discussed.


Assuntos
Fístula Arteriovenosa/metabolismo , Neoplasias Encefálicas/irrigação sanguínea , Glioblastoma/irrigação sanguínea , Oligodendroglioma/irrigação sanguínea , Albumina Sérica/farmacocinética , Idoso , Neoplasias Encefálicas/diagnóstico , Angiografia Cerebral , Feminino , Glioblastoma/diagnóstico , Humanos , Pulmão/diagnóstico por imagem , Pulmão/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oligodendroglioma/diagnóstico , Cintilografia , Tecnécio
17.
Acta Neurochir Suppl ; 78: 125-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11840705

RESUMO

The goals of the morbidity and mortality conference are learning from mistakes, recognising problems, and being aware of the risks of one's own procedures. Data are continuously collected, complications are classified, and the results of surgery are analyzed. By analysing and discussing the results every three months, total case mortality, mortality of specific procedures, incidence of haematomas, infection rate and incidence of thromboses and emboli are known and a continuous quality control is possible.


Assuntos
Capacitação em Serviço/métodos , Procedimentos Neurocirúrgicos/mortalidade , Complicações Pós-Operatórias/mortalidade , Garantia da Qualidade dos Cuidados de Saúde/métodos , Gestão de Riscos/métodos , Humanos , Complicações Pós-Operatórias/prevenção & controle , Medição de Risco , Suíça
18.
Neurosurgery ; 47(6): 1449-51, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11126918

RESUMO

OBJECTIVE AND IMPORTANCE: Complications usually occur when they are least expected. We present an unusual case of nerve entrapment after microsurgical discectomy. CLINICAL PRESENTATION: A patient undergoing uneventful first lumbar microsurgical discectomy developed severe back and leg pain and a progressive neurological deficit during the first postoperative night. Herniation of cauda equina nerve roots had occurred through an unnoticed minimal defect in the dura, which had not caused cerebrospinal fluid leakage. The roots were incarcerated and swollen, and they filled the space of the resected nucleus pulposus. It was presumed that elevation of intra-abdominal pressure and consequent increased intraspinal pressure during extubation led to the herniation of arachnoid and cauda equina roots. The nerve roots were then trapped and incarcerated in the manner of bowel loops in an abdominal wall hernia. INTERVENTION: During reoperation, the nerve roots were repositioned into the dural sac. The patient recovered without further complications and without long-term sequelae. CONCLUSION: All dural tears that occur during intraspinal surgery, even if they are small and the arachnoid is intact, should be closed with stitches or at a minimum with a patch of muscle or gelatin sponge with fibrin glue. Care should be taken to avoid increased intra-abdominal pressure during extubation. Excessive pain and progressive neurological dysfunction occurring shortly after microsurgical lumbar discectomy or any intraspinal procedure is indicative of possible hemorrhage with subsequent compression of nerve roots. The case reported here provides anecdotal evidence that this situation can also be caused by a herniation of cauda equina nerve roots through a small dural defect that was not evident during the initial operation.


Assuntos
Discotomia , Vértebras Lombares/cirurgia , Microcirurgia , Polirradiculopatia/etiologia , Complicações Pós-Operatórias , Cauda Equina , Feminino , Hérnia/etiologia , Herniorrafia , Humanos , Pessoa de Meia-Idade , Mielografia , Polirradiculopatia/diagnóstico por imagem , Polirradiculopatia/cirurgia , Reoperação , Raízes Nervosas Espinhais/cirurgia , Tomografia Computadorizada por Raios X
19.
J Neurosurg ; 93(5): 762-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11059655

RESUMO

OBJECT: Closure of the sella turcica after transsphenoidal surgery is mainly accomplished with autologous muscle fascia and fat or muscle; this requires a second surgical incision. The authors review the results of using resorbable vicryl patches, gelatin foam, and fibrin glue for sellar reconstruction. METHODS: A review was conducted of 376 consecutive patients who underwent surgery for pituitary adenomas, cysts, or subdiaphragmatic craniopharyngiomas in the sella turcica that the senior author (R.W.S.) had performed or directly supervised over the last 10 years. The sellar reconstruction was performed with a commercially available, synthetic absorbable patch composed of polyglactin 910/poly-p-dioxanone, gelatin foam, and fibrin glue. The patch is essentially resorbed in 2 to 3 months and replaced by fibrous collagen tissue. There were 117 small, 112 medium-sized, and 147 large lesions. The overall nonendocrine postoperative morbidity rate was 2.8%, and included visual deterioration, meningitis, secondary epistaxis, nasal septum complication, and cerebrospinal fluid (CSF) leakage. Two patients with macroadenomas needed reoperation for persistent CSF leakage, which comprised 0.5% of the whole series or 0.8% of the 259 patients with medium-sized or large lesions. There was no mortality and no morbidity related to the implanted material, and in particular no delayed empty sella syndrome. CONCLUSIONS: Closure of the sella turcica with a synthetic absorbable vicryl patch, gelatin foam, and fibrin glue after transsphenoidal surgery is safe and very effective in preventing postoperative CSF fistulas. The use of this technique obviates the need for a second surgical incision and shortens the operating time. Because of the progressive resorption of the substitute material, the interpretation of postoperative magnetic resonance studies was not significantly hindered.


Assuntos
Adenoma/cirurgia , Neoplasias Hipofisárias/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Sela Túrcica/cirurgia , Adenoma/diagnóstico , Cistos do Sistema Nervoso Central/cirurgia , Meios de Contraste , Craniofaringioma/cirurgia , Adesivo Tecidual de Fibrina/uso terapêutico , Gadolínio DTPA , Esponja de Gelatina Absorvível/uso terapêutico , Hemostáticos/uso terapêutico , Humanos , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias/diagnóstico , Poliglactina 910/uso terapêutico , Osso Esfenoide/cirurgia , Resultado do Tratamento
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