The mdx mutant mouse was first observed during a survey of genetic variations of pyruvate kinase in the mouse. Affected mice have high serum levels of this enzyme and although showing little disability they have widespread and severe muscle disease. Light and electron microscopy, muscle enzyme histochemistry and combined cholinesterase-silver impregnations were used for the study of affected and control animals aged 1 day to 1 year. An early ultrastructural abnormality present already at 1 day was scattered focal streaming of Z-lines. Later there was also segmental muscle fibre necrosis and regeneration. The proportion of muscle fibres showing either necrosis, regeneration or internal nuclei was assessed in several muscles, at ages ranging from 10 days to 1 year. Acute segmental necrosis and regeneration were most marked at 1 to 2 months, although they were present at all ages. The number of fibres with internal nuclei increased progressively until 3 months when 70-80% showed this abnormality. Nerve terminals were unaffected but there was a reduction in the number and depth of postsynaptic folds at motor end-plates in adult animals, confirmed by morphometric analysis. Quantitative study of L4 motor root and tibial nerve showed that fibre numbers, axonal calibres and myelin sheath thickness were normal at all ages. No qualitative abnormalities were found in the CNS or other organs. The findings strongly suggest that the mdx mutant has a primary muscle disease and that the nervous system is normal.

BackgroundChoroid plexus carcinomas (CPC) are rare tumors predominantly found in children. Given the high frequency of the germline R337H mutation in the TP53 gene in southern Brazil, we have evaluated the frequency of the R337H mutation in families with CPC in children.Methodology/Principal FindingsThe present series included 29 patients that were admitted to the same institution from 1992 to 2010, including 22 children with CPC (0.08–13.6 years of age at diagnosis) and 7 children with papilloma of the choroid plexus (Pp; 0.5–9.8 years of age). Surgical resection was possible in 28 children. Blood and/or tumor DNA was extracted and analyzed using PCR-RFLP and results were confirmed by sequencing 240 bp of the TP53 exon 10. The patients, all parents, and some relatives submitted samples for blood DNA analysis. In addition, we have also examined the presence of the mutation in DNA from paraffin-embedded tumor samples to evaluate loss of heterozygosity. We found 63.3% (14/22) of the CPC patients positive for the germline R337H mutation; CPC samples were either heterozygous (n = 7), lost only the wild-type (n = 4), or only the R337H copy (n = 2). One CPC sample was not available. All Pp cases (7/7, 100%) were negative for R337H. Cure (>5 years survival free of disease) was observed in 18.1% of the CPC cases with the R337H mutation (2/11), 71.4% of the Pp (5/7), and 25% of CPC cases negative for the R337H mutation (2/8). Family history of cancer (with 2 or more cancer cases) was exclusively identified on the parental side segregating the R337H mutation, and 50% (7/14) of them were compatible with Li-Fraumeni-like syndrome.SignificanceOur results show for the first time that the R337H TP53 mutation is responsible for 63% of the CPC cases in children, suggesting a higher incidence of CPC in southern Brazil.

Primary meningiomas of the jugular foramen are extremely rare. There is controversy regarding the management of these tumors. The objective of this article is to analyze the treatment and results in a series of ten cases. From a series of 107 patients that had been operated on for jugular foramen tumors between 1987 and 2005, ten had meningiomas. The clinical, histological and imaging findings, as well as the outcome of these cases, were reviewed. A high incidence of malignant or aggressive tumors (six cases) was found. Gross total resection (Simpson I and II) was achieved in five patients. Four patients with meningotheliomatous meningiomas are alive, with a mean follow-up time of 71.8 months (6.5 years). Two patients (one with anaplastic type and one with papillary type) died in the immediate postoperative period. Four patients (two with papillary type, one with microcystic type and one with anaplastic type) died because of disease progression, with a mean survival time of 35 months. Radical removal of benign jugular foramen meningiomas is possible. The incidence of postoperative deficit of cranial nerves is higher than in other benign tumors of the jugular foramen. A high incidence of aggressive (malignant) tumors was observed in this series.

SummaryTissue microarray technology enables us to evaluate the pattern of protein expression in large numbers of samples. However, manual data acquisition and analysis still represent a challenge because they are subjective and time-consuming. Automated analysis may thus increase the speed and reproducibility of evaluation. However, the reliability of automated analysis systems should be independently evaluated. Herein, the expression of phosphorylated AKT and mTOR was determined by ScanScope XT (Aperio; Vista, CA) and ACIS III (Dako; Glostrup, Denmark) and compared with the manual analysis by two observers. The percentage of labeled pixels or nuclei analysis had a good correlation between human observers and automated systems (κ = 0.855 and 0.879 for ScanScope vs. observers and κ = 0.765 and 0.793 for ACIS III vs. observers). The intensity of labeling determined by ScanScope was also correlated with that found by the human observers (correlation index of 0.946 and 0.851 for pAKT and 0.851 and 0.875 for pmTOR). However, the correlation between ACIS III and human observation varied for labeling intensity and was considered poor in some cases (correlation index of 0.718 and 0.680 for pAKT and 0.223 and 0.225 for pmTOR). Thus, the percentage of positive pixels or nuclei determination was satisfactorily performed by both systems; however, labeling intensity was better identified by ScanScope XT. (J Histochem Cytochem 61:272-282, 2013)

No abstract

No abstract

Granular cell tumor (GCT) usually occurs as a solitary, small, nodular tumor and rarely grows to a sufficient size to present symptoms. The tumor is more prevalent in female adults. The authors report a case of an 8-year-old boy with GCT of the neurohypophysis presenting with central precocious puberty. Few cases of symptomatic GCT have been reported in the literature, none of them in a patient in the first decade of life. Clinical picture, histopathological features, and histogenesis of GCT of neurohypophysis are discussed.

RESUMO -No presente estudo, foram pesquisados os tumores do sistema nervoso central (SNC) diagnosticados na cidade de Curitiba entre 1990 e 1994. Realizaram-se 2371 biópsias de SNC das quais 1340 casos eram neoplasias primárias. Dentre as neoplasias primárias de SNC 304 (22,6%) eram meningiomas. Duzentos e nove meningiomas ocorreram em mulheres (68,7%) e 95 ocorreram em homens (31,3%). As idades variaram de 3 a 90 anos, com média de 45,8 anos. Duzentos e oitenta meningiomas localizavam-se no cérebro, 10 na medula espinhal, 9 no cerebelo e 5 na emergência de nervos cranianos. Na classificação histológica verificou-se que 294 (96,7%) eram do tipo clássico, 6 malignos (ou anaplásicos), 3 atípicos e 1 papilar. No grupo dos meningiomas clássicos 267 eram meningoteliais, 10 psamomatosos, 5 fibroblásticos, 5 microcísticos, 5 transicionais e 2 angiomatoses. Os autores concluem que as neoplasias meníngeas representaram o grupo mais frequente de tumores primários do SNC e apresentaram características epidemiológicas e anátomo-patológicas similares às da literatura mundial, na qual é dada ênfase à dificuldade de estabelecer critérios biológicos e histológicos de malignidade neste grupo de tumores. PALAVRAS-CHAVE: tumor cerebral, meningioma, epidemiologia, histopatologia. Meningiomas: epidemiological and pathological studies of 304 casesABSTRACT -The authors have retrospectively reviewed all tumors of central nervous system (CNS) operated at the most important neurosurgery hospitals of Curitiba in a 5-year period (1990)(1991)(1992)(1993)(1994) and found 304 (22.4%) cases of meningioma. Age mean of the patients was 48.5 years, with a range of 3 to 90 years. A marked female preponderance (68.7%) was noted. The most common tumor location was brain (n=280) and the remaining cases occurred in spinal cord (n=10), cerebellum (n=9) and cranial nerves (n=5). Histologically, there were 294 (96.7%) meningiomas of the classical type, six malignant or anaplastic, three atypical and one papillary. Two hundred and sixty seven classical meningiomas were from the meningotelial subtype, ten psamomatousos, five fibroblastic, five microcystic, five transicional and two angiomatous. The authors conclude that meningiomas are one of the most common group of primary neoplasias of CNS and the definition of malignancy in those tumors is beset by frequent discordance between histologic and biologic features.KEY WORDS: brain tumor, meningioma, epidemiology, histopathology.O conhecimento do comportamento biológico das neoplasias depende diretamente do correto diagnóstico anátomo-patológico e de elementos clínicos e epidemiológicos. Inúmeros estudos demonstram a relação entre o meio ambiente e o desenvolvimento de algumas neoplasias. Diante disto, em 1990, foi criado o