RESUMO
Ancient schwannoma is an uncommon schwannoma variant which is a benign tumour of Schwann cell origin. It is relatively a rare tumour (25%) in the head and neck region. It is encapsulated and well demarcated from the surrounding tissues. A 35 years old patient in this case presented with painless swelling of the tongue. Trans-oral excision of the intramural lesion was performed. Histopathological and immuno-histochemistry confirmed the diagnosis of schwannoma. This case is of interest on account of the complexity of its diagnosis and the atypical site, that is, intra-mural, of appearance of a schwannoma.
RESUMO
A platelet aggregation inhibitor phospholipase A(2) (NND-IV-PLA(2)) was isolated from Naja naja (Eastern India) venom by a combination of cation and anion exchange chromatography. NND-IV-PLA(2) is the most catalytically active enzyme isolated from the Indian cobra venom. The acidic PLA(2) profile of Eastern regional Indian cobra venom is distinctly different from that of the western regional venom. However the acidic PLA(2)s from both the regions follow the pattern of increasing catalytic activity with increase in acidic nature of the PLA(2) isoform. NND-IV-PLA(2) is a Class B1 platelet aggregation inhibitor and inhibits platelet aggregation induced by ADP, collagen and epinephrine. Modification of active site histidine abolishes both catalytic activity and platelet aggregation inhibition activities while aristolochic acid, a phospholipase A(2) inhibitor has only partial effect on the two activities.
