Flávio Key Miura

Galectin-3 as an Immunohistochemical Tool to Distinguish Pilocytic Astrocytomas from Diffuse Astrocytomas, and Glioblastomas from Anaplastic Oligodendrogliomas

The distinction of astrocytomas and oligodendrogliomas, mainly pilocytic astrocytomas (PILOs) from infiltrating astrocytomas and oligodendrogliomas (ODs), and high‐grade oligodendrogliomas from glioblastomas (GBMs), poses a serious clinical problem. There is no useful immunohistochemical (IHC) marker to differentiate these gliomas, and sometimes the differential diagnosis between them is arbitrary. We identified galectin‐3 (Gal‐3) as a possible tool to differentiate them based on gene expression profiles of GBMs. We confirmed the differential expression in 45 surgical samples (thirteen GBMs; seven PILOs; 5 grade II ODs; 5 anaplastic oligodendrogliomas [AODs], including 2 Oligo‐astrocytomas; 8 diffuse astrocytomas [ASTs], and 7 non‐neoplastic samples) by quantification of Gal‐3 gene expression by real‐time quantitative PCR (rt‐PCR). Higher expression of Gal‐3 was observed in GBMs and PILOs than in OD, AODs and ASTs. The IHC expression of Gal‐3 was evaluated in 90 specimens (fifteen PILOs, fourteen ASTs, 10 anaplastic astrocytomas, fifteen GBMs, eleven ODs, fifteen AODs, and 10 dysembryoplastic neuroepithelial tumors). The mean labeling score for Gal‐3 determined according to the percentage of labeled cells in the tumor bulk was significantly different in GBMs versus AODs and in PILOs versus ASTs. Hence, Gal‐3 is differentially expressed in central nervous system tumors, making IHC detection of Gal‐3 a useful tool in distinguishing between these gliomas.

IDH1 mutations in a Brazilian series of Glioblastoma

GBM may manifest rapidly de novo(primary GBM), or may develop slowly from grade II orgrade III astrocytomas (secondary GBM), suggesting thatthey are distinct disease entities that evolve throughdifferent genetic pathways.In recent genome-wide analyses, high rates of sponta-neous mutations in the gene encoding cytosolic NADP-dependent isocitrate dehydrogenase 1 (IDH1) have beenreported in diffuse gliomas including WHO grades II andIII astroglial and oligodendroglial lineages.

Causes and treatment of intracranial haemorrhage complicating shunting for paediatric hydrocephalus

Abstract Intracranial haematomas are a well-known complication of shunting procedures for hydrocephalic patients. Most are subdural haematomas, and epidural haematomas are much less common in this setting. Their aetiology is thought to be due to an overdrainage of cerebrospinal fluid and a rapid lowering of intracranial pressure, leading to the development of these haematomas. Since the advent of modern neuroimaging techniques, prompt diagnosis of postshunting intracranial haematoma has been possible even in asymptomatic patients. The choice between surgical and nonsurgical management of postshunting intracranial haematoma is a difficult and controversial issue, especially in asymptomatic patients. Several therapeutic options have been proposed for the treatment of postshunting intracranial haematoma. Evacuation of the haematoma by conventional neurosurgical methods with the implantation of a higher pressure valve system is the most common option adopted. Intraventricular haemorrhage is occasionally reported, chiefly in children with hydrocephalus associated with vein of Galen malformation.

Xenograft transplantation of human malignant astrocytoma cells into immunodeficient rats: an experimental model of glioblastoma

INTRODUCTION: Astrocytic gliomas are the most common intracranial central nervous system neoplasias, accounting for about 60% of all primary central nervous system tumors. Despite advances in the treatment of gliomas, no effective therapeutic approach is yet available; hence, the search for a more realistic model to generate more effective therapies is essential. OBJECTIVE: To develop an experimental malignant astrocytoma model with the characteristics of the human tumor. METHOD: Primary cells from subcutaneous xenograft tumors produced with malignant astrocytoma U87MG cells were inoculated intracerebrally by stereotaxis into immunosuppressed (athymic) Rowett rats. RESULTS: All four injected animals developed non-infiltrative tumors, although other glioblastoma characteristics, such as necrosis, pseudopalisading cells and intense mitotic activity, were observed. CONCLUSION: A malignant astrocytoma intracerebral xenograft model with poorly invasive behavior was achieved in athymic Rowett rats. Tumor invasiveness in an experimental animal model may depend on a combination of several factors, including the cell line used to induce tumor formation, the rat strains and the status of the animal’s immune system.

Unusual cause for bilateral trigeminal neuralgia: unilateral racemous cysticercus of cerebellopontine angle. Case report

We report the case of a 42-year-old woman with a racemous cystecercus in the right cerebellopontine angle (CPA), who presented with bilateral trigeminal neuralgia. The parasite was completly removed via a right suboccipital craniotomy. On the first postoperative day, the patient indicated that the pain disappeared. The neuralgia was caused by two probable mechanisms: a distortion of the brain stem and compression of the nerve against an arterial loop at the entry zone or arachnoiditis caused by the parasite in the both CPA cisternae. This case demonstrates the advisability of obtaining imaging studies in all patients with trigeminal neuralgia before starting any management. We must always remind that the cysticercus may be a differential diagnosis of CPA lesions.

Low-grade astrocytoma: surgical outcomes in eloquent versus non-eloquent brain areas

A retrospective study of 81 patients with low-grade astrocytoma (LGA) comparing the efficacy of aggressive versus less aggressive surgery in eloquent and non-eloquent brain areas was conducted. Extent of surgical resection was analyzed to assess overall survival (OS) and progression- free survival (PFS). Degree of tumor resection was classified as gross total resection (GTR), subtotal resection (STR) or biopsy. GTR, STR and biopsy in patients with tumors in non-eloquent areas were performed in 31, 48 and 21% subjects, whereas in patients with tumors in eloquent areas resections were 22.5, 35 and 42.5%. Overall survival was 4.7 and 1.9 years in patients with tumors in non-eloquent brain areas submitted to GTR/STR and biopsy (p=0.013), whereas overall survival among patients with tumors in eloquent area was 4.5 and 2.1 years (p=0.33). Improved outcome for adult patients with LGA is predicted by more aggressive surgery in both eloquent and non-eloquent brain areas.

Hemólise em circulação extracorpórea: estudo comparativo entre bomba de rolete e bomba centrífuga

O uso de bomba centrifuga como suporte circulatorio para pacientes em choque cardiogenico, apos a realizacao de cirurgia cardiaca e como suporte para pacientes com falencia cardiaca que estao aguardando doacao para transplante cardiaco, tem sido progressivamente ampliado. Alguns centros utilizam a bomba centrifuga em circulacao extracorporea de rotina, como substituto do rolete arterial,. No INCOR, operamos dois grupos de pacientes triarteriais submetidos a revascularizacao do miocardio, operados pelo mesmo cirurgiao, com o mesmo metodo de protecao miocardica (cardioplegia cristaloide, hipotermia sistemica a 28oC e topica com soro fisiologico). Todos os parâmetros dos dois grupos foram sem diferenca estatistica no pre-operatorio: idade, sexo, superficie corporea e parâmetros hematologicos. Foram operados 27 pacientes consecutivos e divididos, alternadamente, em 13 pacientes com bomba centrifuga e 14 com rolete arterial. O oxigenador utilizado em todos foi o de bolhas da Macchi. O perfusionista foi sempre o mesmo. O tempo de perfusao medio foi de 105 minutos no Grupo 1 (rolete) e 103 minutos no Grupo 2 (bomba centrifuga). Analisamos os seguintes parâmetros: haptoglobina (HP), tempo de tromboplastina parcial ativada (TTPA), tempo de trombina (TT) e numero e plaquetas pre e pos circulacao extracorporea e, comparando-se os dois grupos, nao houve diferenca estatistica significante entre eles, nos diversos parâmetros. Concluimos que, para circulacao extracorporea com duracao habitual, nao ha diferenca hematologica no uso da bomba centrifuga em relacao ao rolete arterial.

Experimental nodel of C6 brain tumors in athymic rats

Malignant brain tumor experimental models tend to employ cells that are immunologically compatible with the receptor animal. In this study, we have proposed an experimental model of encephalic tumor development by injecting C6 cells into athymic Rowett rats, aiming at reaching a model which more closely resembles to the human glioma tumor. In our model, we observed micro-infiltration of tumor cell clusters in the vicinity of the main tumor mass, and of more distal isolated tumor cells immersed in normal encephalic parenchyma. This degree of infiltration is superior to that usually observed in other C6 models.

Falx osteochondroma: case report and review of the literature

One case of an intracranial osteochondroma originating from the falx is described. The tumor was partially removed. Surgical aspects and etiopathogenesis of falx chondromas are discussed. The values of computerized tomography and magnetic resonance are emphasized.

Depressed skull fractures in children under 2 years of age. Retrospective study of 43 cases

Depressed skull fractures (DSF) in infancy and childhood are frequent but only a few articles make an analysis in children with age between 0 and 2 years. This is a retrospective study of 43 patients with DSF and age ranged from 0 to 2 years. Falls and traffic accidents were the most common causes. Most patients were admitted in alert state. 69.8% of the patients were submitted to surgical treatment. The parietal bone was more frequently injured (55.8%). Most of the patients had type 1 DSF (the depressed bone remains connected to the cranial vault). The incidence of associated lesions of nervous system was lower than reported in the literature.