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ABSTRACT: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas.
Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients.
CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two.
Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.
Journal of Neuroimaging 02/2006; 16(1):52-8. · 1.51 Impact Factor
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ABSTRACT: The mode of tumor invasion has been suggested to have a relationship to the occurrence of cervical metastasis and to prognosis in oral squamous cell carcinoma (OSCC). However, a tumor usually does not have a single mode of invasion, and the importance, if any, of the relative proportions of different modes for metastatic potential has not been studied. Forty two cases of OSCC resected with cervical lymph nodes were selected, 20 of which had nodal metastases and 22 which had not. The mode of invasion in the tumor-host interface was classified as: I - pushing borders, II - bands, III - thin cords, IV - single cells and analyzed in 20 consecutive medium power fields. Also studied were other morphological parameters: perineural and angiolymphatic invasion, tissue eosinophilia, mitosis and intensity of inflammatory infiltrate at the tumor-host interface. The majority of the cases (95.2%) showed two or more modes of invasion. Modes I, II and III occurred with similar frequency in cases with and without metastases. Mode II was the commonest and most extensive in both groups. No mode of invasion was significantly associated with metastases, independent of its extension. The other morphological parameters were neither significantly associated with cervical metastasis. In conclusion, OSCC usually shows two or more modes of tumor invasion if a large extension of tumor-host interface is analyzed. However, the relative proportions of the modes have no correlation with the metastatic potential.
Neoplasma 02/1999; 46(5):323-8. · 1.44 Impact Factor
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ABSTRACT: Primary neoplasms of choroid plexus are rare. Six morphological variants have been described: papillary, cystic, acinar, mucus-secreting, oncocytic, and anaplastic. The anaplastic variant, the so-called choroid plexus carcinoma, is the rarest of all and can metastasize. The differential diagnosis of the anaplastic variant of choroid plexus neoplasms with adenocarcinomas, melanomas and undifferentiated neoplasms can be troublesome chiefly in adults. The now large use of immunocytochemical techniques in tissue section has become a powerful tool in the analysis of cell lineages, tumoral and non-tumoral. Nevertheless, the choroid plexus neoplasms have shown a complex and a somewhat confusing pattern of antigenic expression. In two choroid plexus carcinomas (one localized in the right lateral ventricle from a boy of 1 year and 9 months old, and the other localized in the left lateral ventricle from a girl of 3 years old) the following antigens were searched (using the avidin-biotin-peroxidase complex): glial fibrillary acidic protein (GFAP) with monoclonal and polyclonal antibodies; cytokeratins of 40-50kDa, cytokeratins of 60-70kDA (callus cytokeratin), neuronal specific enolase (NSE) and S-100 protein with monoclonal antibodies. The two neoplasms showed immunoreactivity against NSE, S-100 protein and cytokeratin of 40-50kDA. The neoplasm of the boy exhibited glial differentiation having immunoreactivity against GFAP with monoclonal and polyclonal antibodies.
Arquivos de Neuro-Psiquiatria 10/1990; 48(3):336-40. · 0.72 Impact Factor
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ABSTRACT: Bothrops insularis snake venom was fractionated by gel filtration on Sephadex G-150 followed by ion-exchange chromatography on SP-Sephadex C-25. Two active fractions were purified to homogeneity: (1) SIII-SpI, approximate mol. wt 32,000 and N-terminal amino acid residue Val. This fraction showed esterase activity on TAME, edema-inducing activity on the rat hind paw and contractile activity on the isolated guinea pig ileum. The latter two activities were antagonized by benadryl plus methysergide; (2) SIII-SpVI, a myonecrotic and edema-inducing phospholipase, approximate mol. wt 29,000, N-terminal amino acid residue pyro-Glu, consisting of two chains of approximately 15,000 mol. wt each linked by disulphide bridge(s). The induction of edema by this fraction was not antagonized by benadryl plus methysergide, indomethacin, BW755C or BN52021, but it was antagonized by dexamethasone. Three highly purified hemorrhagic heterodimeric fractions, SIII-SpIII-3, SIII-SpIII-4 and SIII-SpIII-5, of approximate mol. wts 26,000, 29,000 and 26,000, and having N-terminal residues of Asx, Asx and Gly, respectively, were further isolated by preparative polyacrylamide slab gel electrophoresis. SIII-SpIII-4 and SIII-SpIII-5 increased the recalcification time of citrated rat plasma. None of the five isolated fractions showed any proteolytic (on casein) or kininogenase activity.
Toxicon 02/1990; 28(3):261-73. · 2.51 Impact Factor
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ABSTRACT: A myotoxin, bothropstoxin (BthTX), showing no detectable phospholipase A2 activity, was purified to homogeneity from the venom of the Brazilian snake Bothrops jararacussu by a combination of gel filtration on Sephadex G-75 and ion-exchange chromatography on SP-Sephadex C-25. Four phospholipases (Sm-SP1 to Sm-SPIV) were also isolated, the latter showing, similarly to BthTX (Sm-SPv) myonecrotic activity. Approximate mol. wts, as determined by SDS-PAGE, and pI of Sm-SPI to Sm-SPIV are: 22,400-4.2; 15,500-4.8; 13,800-6.9; and 13,200-7.7, respectively. BthTX is a single chain protein, approximate mol. wt 13,000, with 16 half-cystine residues, pI = 8.2 and LD50 = 7.5 mg/kg (i.p.) and 4.8 mg/kg (i.v.) for 20 g mice. The ten first N-terminal amino acid residues show a significant homology to other toxins with phospholipase structure. BthTX is specifically myotoxic, contrary to crude B. jararacussu venom which, although also myotoxic, affects intramuscular arteries and veins leading to thrombosis. BthTX and Sm-SPIV also differ from toxins isolated from the venom of other Brazilian snakes which are strongly hemorrhagic.
Toxicon 02/1988; 26(7):615-27. · 2.51 Impact Factor
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ABSTRACT: Haemorrhagic factor HF2 and bothropasin, two metalloproteins isolated from the venom of Bothrops jararaca, caused haemorrhage followed by myonecrosis and arterial necrosis after i.m. injection in mice. The effects of HF2 were qualitatively similar to those of bothropasin and crude B. jararaca venom, but its potency was about 20 times higher. The haemorrhagic and necrotizing actions of these components are unrelated to their proteolytic activity on casein.
Toxicon 02/1985; 23(2):341-5. · 2.51 Impact Factor
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ABSTRACT: The local tissue effects of crude Bothrops neuwiedi snake venom and of its hemorrhagic factor (NHF) were studied on mouse tibialis anterior muscle in vivo. After 6 h, 8 days and 6 weeks the muscles were examined in paraffin sections stained with hematoxylin and eosin. Both NHF and crude venom produced hemorrhage and myonecrosis, later followed by muscle fiber regeneration. Intramuscular arteries also suffered necrosis. The minimal dose of NHF necessary to produce detectable hemorrhage and myonecrosis was 50 ng, while the minimal venom dose needed to produce the same effect was 20 times higher. The results indicate that NHF is one of the major factors responsible for the local effects of B. neuwiedi venom.
Brazilian Journal of Medical and Biological Research 02/1985; 18(3):337-40. · 1.13 Impact Factor
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ABSTRACT: The lesions caused by sublethal doses of Bothrops jararacussu venom injected into tibialis anterior (tib. ant.) muscles of mice were studied with paraffin sections. Doses of 5 and 20 micrograms produced a large area of necrosis in tib. ant., but hardly affected neighbouring muscles. Phagocytosis of necrotic remnants was followed by marked regeneration of the muscle fibres. Within two weeks of the 5 micrograms dose there was recovery to near normal appearance and slight fibrosis. With 20 micrograms, a circumscribed scar and stronger interstitial fibrosis developed in the tib. ant. Most regenerated muscle fibres were small, but varied in diameter, retained central nuclei for three months (the longest survival) and were surrounded by collagen. Doses of 80 and 200 micrograms produced widespread coagulative necrosis of tib. ant., though neighbouring leg muscles were relatively spared. Myonecrosis was evident microscopically at 10 min, and over the next week the necrotic muscle remained acellular and devoid of inflammatory reaction except at the very edge. Blood vessels within and outside tib. ant. often became hyalinized and thrombosed. Phagocytosis of debris proceeded from the periphery, and after two weeks the muscle was replaced by fibro-adipose tissue. There was little if any muscle fibre regeneration. Abscesses developed in the vicinity of the injection site in several mice receiving high venom doses, but never after low doses or saline. Muscle necrosis after B. jararacussu venom seems due primarily to direct action of the venom, though vascular thrombosis and ischaemia may contribute. The venom can cause fibrosis of muscle and hinder or prevent muscle fibre regeneration.
Toxicon 02/1984; 22(3):339-46. · 2.51 Impact Factor
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ABSTRACT: In one case of repeated ingestions of arsenic over a period of one year, the value of sectional toe nail analysis was investigated. The arsenic determinations were performed by instrumental neutron activation analysis. After subdividing the nail transversely into segments of 0.5 mm length, several maxima and minima of arsenic concentrations were found. Taking the nail growth into consideration, these characteristics of curve correspond to the known dates of treatments and of dismissals from the hospital. The results exclude an external arsenic contamination of the nail.
Archive für Toxikologie 08/1982; 50(2):125-31. · 4.67 Impact Factor
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ABSTRACT: Spinal cord lesions are rare in schistosomiasis. Schistosomal ova usually elicit a granulomatous myelitis in which necrotic foci are sometimes observed, but necrotic foci are sometimes observed, but extensive cord necrosis is exceptional. A 19-year-old Brazilian woman had transverse myelitis that ended fatally one month and a half thereafter. Autopsy disclosed a total myelonecrosis below T-4, and ova at Schistosoma mansoni were demonstrated in the necrotic cord tissue and leptomeniges. This is, to our knowledge, the most extensive necrosis of the spinal cord reported to date in schistosomiasis.
Archives of Neurology 09/1979; 36(8):517-9. · 7.58 Impact Factor
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ABSTRACT: Central nervous system involvement in Candida septicaemia is rare and not more than four cases have been published in Brazil. Five new cases of systemic candidiasis with cerebral lesions are reported. All patients (four adults and a child) had serious underlying diseases and were submitted to heavy long-term antibiotic therapy with multiple drugs. Seizures in one case and neck stiffness in another were the only neurologic signs that could be attributed to candidiasis. In no case were the lesions severe enough to be considered an immediate cause of death. In three patients, no macroscopic changes were evident in the brain, but microabscesses and granulomata were observed on microscopical examination; another patient had two gross areas with necrotic and haemorrhagic appearance in the cerebral hemispheres; the child had only two microscopic granulomata. The aetiological agent was demonstrated by Grocott's methenamine silver technique in all cases. Involvement of organs other than the central nervous system could be demonstrated in three autopsies. Discussion is confined mainly to such aspects as the contributory factors in the pathogenesis of systemic candidiasis as well as the marked rise in the incidence of this condition in the past few decades. It is suggested that the frequence of monilial septicaemia in Brazil may be far more serious than apparent from the scarcity of reported cases.
Arquivos de Neuro-Psiquiatria 04/1976; 34(1):18031. · 0.72 Impact Factor
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ABSTRACT: A case of ependymoblastoma of the pons in a child is reported, the first so far described in this location. The case adds further evidence for the acceptance of ependymoblastomas as a specific variety of primitive human glioma.
The Journal of Pathology 05/1975; 115(4):207-10. · 6.32 Impact Factor
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ABSTRACT: Bothrops insularis snake venom was fractionated by gel filtration on Sephadex G-150 followed by ion-exchange chromatography on SP-Sephadex C-25. Two active fractions were purified to homogeneity: (1) SIII-SpI, approximate mol. wt 32,000 and N-terminal amino acid residue Val. This fraction showed esterase activity on TAME, edema-inducing activity on the rat hind paw and contractile activity on the isolated guinea pig ileum. The latter two activities were antagonized by benadryl plus methysergide; (2) SIII-SpVI, a myonecrotic and edema-inducing phospholipase, approximate mol. wt 29,000, N-terminal amino acid residue pyro-Glu, consisting of two chains of approximately 15,000 mol. wt each linked by disulphide bridge(s). The induction of edema by this fraction was not antagonized by benadryl plus methysergide, indomethacin, BW755C or BN52021, but it was antagonized by dexamethasone. Three highly purified hemorrhagic heterodimeric fractions, SIII-SpIII-3, SIII-SpIII-4 and SIII-SpIII-5, of approximate mol. wts 26,000, 29,000 and 26,000, and having N-terminal residues of Asx, Asx and Gly, respectively, were further isolated by preparative polyacrylamide slab gel electrophoresis. SIII-SpIII-4 and SIII-SpIII-5 increased the recalcification time of citrated rat plasma. None of the five isolated fractions showed any proteolytic (on casein) or kininogenase activity.
Toxicon.
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ABSTRACT: A myotoxin, bothropstoxin (BthTX), showing no detectable phospholipase A2 activity, was purified to homogeneity from the venom of the Brazilian snake Bothrops jararacussu by a combination of gel filtration on Sephadex G-75 and ion-exchange chromatography on SP-Sephadex C-25. Four phospholipases (SIII-SPI to SIII-SPIV) were also isolated, the latter showing, similarly to BthTX (SIII-SPV) myonecrotic activity. Approximate mol. wts, as determined by SDS-PAGE, and pI of SIII-SPI to SIII-SPIV are: 22,400−4.2; 15,500−4.8; 13,800−6.9; and 13,200−7.7, respectively. BthTX is a single chain protein, approximate mol. wt 13,000, with 16 half-cystine residues, pI = 8.2 and (i.p.) and 4.8 mg/kg (i.v.) for 20 g mice. The ten first N-terminal amino acid residues show a significant homology to other toxins with phospholipase structure. BthTX is specifically myotoxic, contrary to crude B. jararacussu venom which, although also myotoxic, affects intramuscular arteries and veins leading to thrombosis. BthTX and SIII-SPIV also differ from toxins isolated from the venom of other Brazilian snakes which are strongly hemorrhagic.
Toxicon.
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ABSTRACT: Glioblastoma multiforme is recognized rarely in the cerebellum. We describe a peculiar case with lipid accumulation in giant tumor cells, possibly the second example so far reported in this unusual location. A 46-year-old man with a 5-month history of headache, vomiting, dizziness and instability of gait, was found to have on magnetic resonance imaging an expanding mass situated deep in the left cerebellar hemisphere. The lesion was hypointense in T 1- and hyperintense in T2-weighted images, had poorly defined borders, peripheral edema and annular foci of contrast enhancement. Eight months after subtotal removal and radiotherapy, control MRI showed tumor recurrence with aggressive features. The patient was alive 15 months after operation but follow-up was eventually lost. Histologically, the tumor showed marked pleomorphism, with many giant cells characterized by finely vacuolated cytoplasm strongly suggestive of lipid accumulation. There were few, sometimes atypical mitotic figures and foci of endothelial proliferation. The tumor cells were strongly positive for GFAP, vimentin and S100 protein, all of which stressed the foamy appearance of the giant cells. About 15% of nuclei were positive for Ki-67. We considered the case to be a so-called lipidized glioblastoma, first recognized as a subtype by Kepes and Rubinstein [1981]. Differential diagnosis with anaplastic pleomorphic xanthoastrocytoma is discussed.
Clinical neuropathology 24(6):262-6. · 1.04 Impact Factor
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Revista do Instituto de Medicina Tropical de São Paulo 26(5):247-53. · 1.00 Impact Factor
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ABSTRACT: A 59-year-old woman with rheumatoid arthritis was treated with prednisone and 250 mg of chloroquine diphosphate (CQ) daily. Though there was improvement in her joint symptoms, she began to notice progressive lower limb weakness, later extending to the arms and lasting for 2 months. Electromyography showed fibrillations, polyphasic potentials and high frequency discharges. Biceps brachii biopsy showed that virtually every muscle fiber and multiple small vacuoles surrounded by a basophilic rim. There was variation in fiber diameter and some fibers were atrophic and angulated. ATPase revealed type grouping. Electron microscopy showed, in each muscle fiber, numerous concentric membranous bodies, some with curvilinear profiles, beneath the sarcolemma or among the myofibrils. Some were also observed in endothelial cells of muscle capillaries. CQ was withdrawn, but no significant regression of symptoms had been observed at the time follow-up was discontinued. The patient died of cardiac insufficiency and bronchopneumonia. The case illustrates a rare complication of CQ therapy of rheumatic conditions. It is noteworthy because the drug was administered in therapeutic doses and only for a short period. CQ is known to interfere with lysosomal function, from which presumably the membranous bodies here described originate. Improvement of neuromuscular symptoms has been reported following withdrawal of the drug.
Clinical neuropathology 15(5):256-8. · 1.04 Impact Factor
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Neurology India 58(4):681-2. · 0.96 Impact Factor
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ABSTRACT: Haemorrhagic factor HF2 and bothropasin, two metalloproteins isolated from the venom of Bothrops jararaca, caused haemorrhage followed by myonecrosis and arterial necrosis after i.m. injection in mice. The effects of HF2 were qualitatively similar to those of bothropasin and crude B. jararaca venom, but its potency was about 20 times higher. The haemorrhagic and necrotizing actions of these components are unrelated to their proteolytic activity on casein.
Toxicon.
