Sérgio Rosemberg

Congenital insensitivity to pain with anhidrosis (hereditary sensory and autonomic neuropathy type IV)

Congenital insensitivity to pain with anhidrosis (CIPA, hereditary sensory and autonomic neuropathy type IV) is an exceedingly rare disease. Only 31 cases have been reported. We report a 4-year-old girl with CIPA and include a complete review of the literature. CIPA is a severe autosomal recessive condition that leads to self-mutilation in the first months of life and to bone fractures, multiple scars, osteomyelitis, joint deformities, and limb amputation as the children grow older. Mental retardation is common. Death from hyperpyrexia occurs within the first 3 years of life in almost 20% of the patients. Ultrastructural and morphometric studies of the peripheral nerves demonstrate a loss of the unmyelinated and small myelinated fibers. The actual physiopathologic mechanism of this developmental disorder remains unknown.

Neuropathology of acquired immunodeficiency syndrome (AIDS). Analysis of 22 Brazilian cases.

The neuropathologic study of 22 Brazilian cases of acquired immuno-deficiency syndrome (AIDS) was performed. Thirteen cases (59%) showed neuropathologic lesions. These included infection by Toxoplasma (n = 4), Cryptococcus neoformans (n = 3), viral encephalitis (n = 4), primary lymphomas (n = 2), isolated cerebral infarct (n = 1), and reactive gliosis (n = 1). In 2 cases, primary lymphoma and viral encephalitis were associated. Axonal spheroids in the gracilis and cuneatus nuclei were present in a case of toxoplasmosis. Mammillary bodies lesions consistent with Wernickes encephalopathy were found in a case of viral encephalitis. In addition, circulatory changes (focal cortical infarcts) were associated lesions in 3 cases. These findings were compared with the main series reported in American and European literature.

Molecular Analysis of Collagen XVIII Reveals Novel Mutations, Presence of a Third Isoform, and Possible Genetic Heterogeneity in Knobloch Syndrome

Knobloch syndrome (KS) is a rare disease characterized by severe ocular alterations, including vitreoretinal degeneration associated with retinal detachment and occipital scalp defect. The responsible gene, COL18A1, has been mapped to 21q22.3, and, on the basis of the analysis of one family, we have demonstrated that a mutation affecting only one of the three COL18A1 isoforms causes this phenotype. We report here the results of the screening of both the entire coding region and the exon-intron boundaries of the COL18A1 gene (which includes 43 exons), in eight unrelated patients with KS. Besides 20 polymorphic changes, we identified 6 different pathogenic changes in both alleles of five unrelated patients with KS (three compound heterozygotes and two homozygotes). All are truncating mutations leading to deficiency of one or all collagen XVIII isoforms and endostatin. We have verified that, in exon 41, the deletion c3514-3515delCT, found in three unrelated alleles, is embedded in different haplotypes, suggesting that this mutation has occurred more than once. In addition, our results provide evidence of nonallelic genetic heterogeneity in KS. We also show that the longest human isoform (NC11-728) is expressed in several tissues (including the human eye) and that lack of either the short variant or all of the collagen XVIII isoforms causes similar phenotypes but that those patients who lack all forms present more-severe ocular alterations. Despite the small sample size, we found low endostatin plasma levels in those patients with mutations leading to deficiency of all isoforms; in addition, it seems that absence of all collagen XVIII isoforms causes predisposition to epilepsy.

Brain bank of the Brazilian aging brain study group—a milestone reached and more than 1,600 collected brains

IntroductionBrain banking remains a necessity for the study of aging brain processes and related neurodegenerative diseases. In the present paper, we report the methods applied at and the first results of the Brain Bank of the Brazilian Aging Brain Study Group (BBBABSG) which has two main aims: (1) To collect a large number of brains of elderly comprising non-demented subjects and a large spectrum of pathologies related to aging brain processes, (2) To provide quality material to a multidisciplinar research network unraveling multiple aspects of aging brain processes and related neurodegenerative diseases.MethodsThe subjects are selected from the Sao Paulo Autopsy Service. Brain parts are frozen and fixated. CSF, carotids, kidney, heart and blood are also collected and DNA is extracted. The neuropathological examinations are carried out based on accepted criteria, using immunohistochemistry. Functional status are assessed through a collateral source based on a clinical protocol. Protocols are approved by the local ethics committee and a written informed consent form is obtained.ResultsDuring the first 21 months, 1,602 samples were collected and were classified by Clinical Dementia Rating as CDR0: 65.7%; CDR0.5:12.6%, CDR1:8.2%, CDR2:5.4%, and CDR3:8.1%. On average, the cost for the processing each case stood at US

Epidemiology of pediatric tumors of the nervous system according to the WHO 2000 classification: a report of 1,195 cases from a single institution.

400. To date, 14 laboratories have been benefited by the BBBABSG.ConclusionThe high percentage of non-demented subjects and the ethnic diversity of this series may be significantly contributive toward aging brain processes and related neurodegenerative diseases understanding since BBBABSG outcomes may provide investigators the answers to some additional questions.

Peritumoral brain edema in benign meningiomas: correlation with clinical, radiologic, and surgical factors and possible role on recurrence

ObjectThe purpose of this study is to determine the epidemiology of tumors of the nervous system diagnosed according to the WHO 2000 classification in a single Brazilian institution.Patients and methodOne thousand one hundred ninety-five tumors in children between 0 and 21 years of age diagnosed between 1974 and 2003 were classified according the sex, topography, and age distribution.ResultsIn all ages, males were slightly more affected. In the first 2 years, the prevalence for boys was higher (68.3%). In the whole series, 58.7% were supratentorial, 31.4% infratentorial, and 9.9% spinal (44% intra- and 56% extramedullary). Among these latter, ependymomas and schwannomas were the most frequent. In the cerebral compartment, pilocytic astrocytomas were the single most frequent tumors (18%), followed by diffuse astrocytomas (14%), medulloblastomas (11%), and craniopharyngiomas (11%). In the posterior fossa, there was an even distribution among medulloblastomas and pilocytic astrocytomas, but the former was much more frequent in the first 2 years of age. High-grade (III and IV) diffuse astrocytomas were slightly more frequent than low grades (II), and this difference becomes more evident as the child grows older. Due to the new development of the surgery of epilepsy, the frequency of neuronal and mixed neuronal–glial tumors is increasing (8%).ConclusionClassified according to the latest WHO classification, by a single neuropathologist in a single institution, this large series of pediatric neurological tumors may reflect fairly well their real incidence. Our results obtained in a developing country do not differ substantially from other similar series reported in the literature from the First World.

Evidence of neuronal migration disorders in Knobloch syndrome: clinical and molecular analysis of two novel families.

BACKGROUND Approximately 60% of meningiomas are associated with peritumoral edema. Various causative factors have been discussed in the literature. The objective of this study was to investigate the correlation of PTBE with clinical, radiologic, and surgical aspects and recurrence of meningiomas. METHODS Sixty-one patients with benign meningiomas were chosen for surgical treatment by the Group of Brain Tumors and Metastasis of the Department of Neurosurgery. All patients underwent complete surgical resection (Simpson grades 1 and 2), and those with atypical and malignant histopathologic grades were excluded. Tumors located in the cavernous sinus, tuberculum sellae, foramen magnum, ventricles, and petroclival region were excluded. RESULTS Edema extension had a positive correlation with the higher recurrence rates (P = .042) and with the presence of irregular margins (P < .011) on bivariate analysis. Meningiomas with larger edema sizes also showed correlation with large meningiomas (P = .035), and the ones with smaller edema sizes correlated with the tentorial location (P = .032). Multivariate analysis showed an association between PTBE and the presence of seizures (odds ratio, 3.469), large meningiomas (odds ratio, 15.977), and for each cubic centimeter added to its size, the risk of edema increased 1.082 times (odds ratio). CONCLUSION Peritumoral brain edema may be related to the invading potential of meningiomas and may play a role in the recurrence potential of the tumor. As a consequence, it is reasonable to consider the presence of edema as an additional factor to be taken into account when mapping out strategies for the treatment of meningiomas.

Leukoencephalopathy, cerebral calcifications, and cysts: New observations

Knobloch syndrome is an autosomal recessive disease characterized by the early onset of severe myopia, vitreoretinal degeneration with retinal detachment, macular abnormalities, and midline encephalocele, mainly in the occipital region. Intra and interfamilial variability is present since the encephalocele is not found in all patients, and the degree of myopia is variable. Analysis of the associated malformations suggests alterations during early neuroectodermal morphogenesis. Only 24 cases have been reported. Recently, the gene responsible for the syndrome, mapped to 21q22.3, was identified. The present study reports on four new cases, revealing the existence of neuronal migratory defects associated with the disorder for the first time.

Correlation of MGMT promoter methylation status with gene and protein expression levels in glioblastoma

We describe three cases of the rare syndrome of leukoencephalopathy, brain calcifications, and cysts. Conventional MRI, proton spectroscopy, and diffusion-weighted imaging yielded additional information on the disease. Imaging findings favor increased water content rather than a demyelinating process in the pathophysiology of this disease. Clinical features of Coats disease and consanguinity were also encountered.

Angioleiomyoma of the cavernous sinus: Case report

OBJECTIVES: 1) To correlate the methylation status of the O6-methylguanine-DNA-methyltransferase (MGMT) promoter to its gene and protein expression levels in glioblastoma and 2) to determine the most reliable method for using MGMT to predict the response to adjuvant therapy in patients with glioblastoma. BACKGROUND: The MGMT gene is epigenetically silenced by promoter hypermethylation in gliomas, and this modification has emerged as a relevant predictor of therapeutic response. METHODS: Fifty-one cases of glioblastoma were analyzed for MGMT promoter methylation by methylation-specific PCR and pyrosequencing, gene expression by real time polymerase chain reaction, and protein expression by immunohistochemistry. RESULTS: MGMT promoter methylation was found in 43.1% of glioblastoma by methylation-specific PCR and 38.8% by pyrosequencing. A low level of MGMT gene expression was correlated with positive MGMT promoter methylation (p = 0.001). However, no correlation was found between promoter methylation and MGMT protein expression (p = 0.297). The mean survival time of glioblastoma patients submitted to adjuvant therapy was significantly higher among patients with MGMT promoter methylation (log rank = 0.025 by methylation-specific PCR and 0.004 by pyrosequencing), and methylation was an independent predictive factor that was associated with improved prognosis by multivariate analysis. DISCUSSION AND CONCLUSION: MGMT promoter methylation status was a more reliable predictor of susceptibility to adjuvant therapy and prognosis of glioblastoma than were MGMT protein or gene expression levels. Methylation-specific polymerase chain reaction and pyrosequencing methods were both sensitive methods for determining MGMT promoter methylation status using DNA extracted from frozen tissue.