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1.
Folia Neuropathol ; 54(1): 40-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27179220

RESUMO

Angiocentric glioma (AG) is a newly-classified, very rare, WHO grade I central nervous system (CNS) lesion, occurring usually in children and young adults. Only 52 patients with AG have been reported so far, making it one of the rarest neuropathological entities. Hereby we present two new cases of AG in young subjects with detailed neuropathological investigations and a neuroradiological picture along with a brief summary of all already published literature reports of this tumor. Histopathological examination of the resected tissue from both cases revealed similar changes characteristic of AG. The tumors were composed of spindle-like, elongated cells, forming characteristic pseudorosettes around vessels and diffusively infiltrating surrounding tissue, trapping neurons between tumor cells. Noticeably, some neoplastic cells encrusting vessels extended far beyond the main tumor mass. Hypothetically, this may be responsible for the recurrence of the tumor even in the case of apparently total excision. In immunohistochemistry, AG cells were glial fibrillary acidic protein (GFAP) and vimentin positive, also exhibiting a strikingly significant epithelial membrane antigen (EMA) dot-like staining pattern. In one of the cases, electron microscopy revealed ependymal differentiation features such as microvilli and cilia. Taken together, all these data strongly confirm a dual astroglial-ependymal nature of the tumor. Follow up corroborates benign character of this neoplasm. Both AGs reported here were immunonegative for the product of the mutated IDH-1 gene what, according to our best knowledge, has never been reported so far. It may suggest that in their pathogenesis AGs differ from grade II astrocytomas, which in most cases harbor a mutation of IDH-1. Noteworthy, neuroimaging in our cases was relatively characteristic but not conclusive, therefore biopsy (at least) is mandatory. A newly proposed so called "A-B-C" classification of long-term epilepsy-associated tumors (LEATs) places AG in a category named ANET. The authors shortly review the A-B-C classification of LEATs.


Assuntos
Neoplasias Encefálicas/patologia , Epilepsia/etiologia , Glioma/patologia , Recidiva Local de Neoplasia/patologia , Adulto , Astrócitos/metabolismo , Astrócitos/patologia , Criança , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Glioma/complicações , Humanos , Imuno-Histoquímica/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Recidiva Local de Neoplasia/complicações , Recidiva Local de Neoplasia/diagnóstico
2.
Folia Histochem Cytobiol ; 40(3): 311-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12219842

RESUMO

The association of amphibian (Xenopus laevis) egg yolk platelet proteins, represented predominantly by lipovitellin, was studied as a model of the formation of amyloid deposits. Two kinds of molecular organization formed by this protein material - native and heat-denatured - were found to exhibit amyloid properties although they differ significantly in structural organization. The first consisted in protein molecules arranged in the natural, physiological, net-like platelet organization, with a tendency to orient uni-directionally. The second was obtained by the gradual removal of Congo red from lipovitellin denatured by heating in an excess of dye. This procedure produced the twisted fibrillar organization of molecules typical for amyloids, represented predominantly by end-to-end associated major polypeptide chains of lipovitellin. Both native and denatured structural forms bind Congo red and produce a green birefringence effect, confirming the near parallel alignment of the complexed Congo red molecules. However, a dye(1,4-bis(1-amino-4-sulfonaphtyl-2-azo)phenylene) closely related to Congo red but with a very weak self-assembling tendency appeared inactive when the spectral shift was studied in a cross-polarization system, indicating in this way that dye supramolecularity is an extra factor which may determine binding to amyloid proteins and specific spectral effects.


Assuntos
Proteínas do Ovo/metabolismo , Óvulo/citologia , Amiloide/química , Amiloidose , Animais , Plaquetas/fisiologia , Feminino , Óvulo/fisiologia , Desnaturação Proteica , Xenopus laevis
3.
Ann Agric Environ Med ; 5(1): 31-43, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9852490

RESUMO

The aim of this study was to identify the specific agents which caused extrinsic allergic alveolitis (EAA) in the selected group of 20 agricultural workers from eastern Poland. The microbiological analysis of the samples of plant materials or dusts reported by the patients as causing symptoms has been carried out, followed by allergological tests (inhalation challenge, agar-gel precipitation test, inhibition of leukocyte migration, skin test) with extrinsic microbial antigens. It was found that the causative agents of allergic alveolitis in the examined group of patients were mesophilic, non-branching bacteria associated with grain dust, mostly Pantoea agglomerans (synonyms: Erwinia herbicola, Enterobacter agglomerans) and Arthrobacter globiformis (each in eight cases). The remaining agents were Alcaligenes faecalis (in two cases), and Brevibacterium linens and Staphylococcus epidermidis (in one case each). On the basis of the clinical picture, the bronchoalveolar lavage (BAL) and allergological tests, the diagnosis of the chronic form of the disease was stated in 14 patients and an acute form - in 6 patients. EAA patients demonstrated in the BAL fluid a typical lymphocytic alveolitis both in terms of percentage and absolute number of lymphocytes. Also, the numbers of eosinophils and neutrophils were significantly higher in EAA patients.


Assuntos
Doenças dos Trabalhadores Agrícolas/epidemiologia , Alveolite Alérgica Extrínseca/epidemiologia , Exposição Ocupacional/efeitos adversos , Adulto , Idoso , Doenças dos Trabalhadores Agrícolas/diagnóstico por imagem , Doenças dos Trabalhadores Agrícolas/etiologia , Doenças dos Trabalhadores Agrícolas/microbiologia , Microbiologia do Ar , Poluentes Ocupacionais do Ar/efeitos adversos , Alérgenos/efeitos adversos , Alveolite Alérgica Extrínseca/diagnóstico por imagem , Alveolite Alérgica Extrínseca/etiologia , Alveolite Alérgica Extrínseca/microbiologia , Arthrobacter/isolamento & purificação , Lavagem Broncoalveolar , Poeira , Grão Comestível/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pantoea/isolamento & purificação , Polônia/epidemiologia , Radiografia
4.
Przegl Lek ; 54(2): 96-102, 1997.
Artigo em Polonês | MEDLINE | ID: mdl-9198831

RESUMO

The experiment were carried out on 40, 3-week old rats who received solutions of aminoacids, glucose, fat, electrolytes, trace elements and vitamins. The ratio of non-protein calories to grams of nitrogen was: Group I-75:1, Group II-200:1, Group III-500:1. Control Group IV was on standard Murigan chow. The analysis included the following parameters: body mass, serum albumin concentration, GOT, GPT and ECH, and microscopic liver studies. The results show that body mass increases in Group I-III (7.5 g, SD 2.18; 1.45 g, SD 2.33; 1.85 g, SD 1.56 respectively) were significantly lower when compared to the controls (11.6 g, SD 2.72), with p < 0.001. Blood serum albumin concentration values were lower in Group I, II and III, and transaminase activity was elevated in comparison to the controls. Histological analysis showed mitochondrial damage and parenchymal degeneration with proliferation of Browicz-Kupfer cells in Group I and III animals, and no structural hepatic changes in Group II and in the controls. The results suggest a relationship between the above disturbances and the composition of the administrated solutions.


Assuntos
Ingestão de Energia , Hepatopatias/etiologia , Nitrogênio/análise , Nutrição Parenteral/efeitos adversos , Soluções/análise , Animais , Índice de Massa Corporal , Hepatopatias/patologia , Masculino , Mitocôndrias Hepáticas/patologia , Nutrição Parenteral/normas , Ratos , Ratos Sprague-Dawley , Albumina Sérica/metabolismo , Soluções/efeitos adversos , Transaminases/sangue
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