The role of the TP53 gene during rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide.

The medium-term tongue carcinogenesis assay is a useful model for studying oral squamous cell carcinomas phase by phase. The aim of the present study was to investigate the expression of p53 by immunohistochemistry and examine the DNA sequence of exons 5, 6, 7, and 8 of Tp53 for mutations during rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide (4NQO). A total of 30 male Wistar rats were treated with 4-nitroquinoline 1-oxide in their drinking water for 4, 12, and 20 weeks at a dose of 50 ppm. Ten animals were used as negative controls. No histopathological changes in the tongue epithelia were observed in the control group or in the treatment group after 4 weeks of 4NQO. Following 12 weeks of treatment, hyperplasia as well as epithelial dysplasia was found in both mild and moderate forms. At 20 weeks, moderate and/or severe oral dysplasia and squamous cell carcinoma of the tongue were found, and the majority of animals had squamous cell carcinoma. The levels of p53 protein were increased (p < 0.05) in pre-neoplastic lesions and in squamous cell carcinomas in some of the tumor cells in squamous cell carcinomas. No mutations were found in any of the exons that were evaluated after the 4-, 12-, or 20-week treatments. Taken together, our results suggest that p53 expression may be an important event in the malignant conversion, whereas Tp53 mutations are not involved in the multi-step tongue carcinogenesis of Wistar rats induced by 4NQO.

Internal carotid artery pseudoaneurysm after tonsillectomy treated by endovascular approach. A case report.

SUMMARY: Surgery on the head and neck region may be complicated by vascular trauma, caused by direct injury on the vascular wall. Lesions of the arteries are more dangerous than the venous one. The traumatic lesion may cause laceration of the artery wall, spasm, dissection, arteriovenous fistula, occlusion or pseudoaneurysm. We present a case of a child with a giant ICA pseudoaneurysm after tonsillectomy, manifested by pulsing mass and respiratory distress, which was treated by endovascular approach, occluding the lesion and the proximal artery with Histoacryl. We reinforce that the endovascular approach is the better way to treat most of the traumatic vascular lesions.

VIII - Síndrome de Bálint relacionada a epilepsia / Bálint's syndrome related to epilepsy

No presente trabalho os autores descrevem um caso de síndrome de Bálint que apareceu após estado de mal epilético relacionado a uma localizaçåo parietal direita. A evoluçåo benigna, com recuperaçåo completa, ilustra que a síndrome de Bálint pode ser devida a alteraçöes funcionais reversíveis do córtex cerebral

VIII - sindrome de Balint relacionada a epilepsia

No presente trabalho os autores descrevem um caso de sindrome de Balint que apareceu apos estado de mal epileptico relacionado a uma localizacao pariental direta. A evolucao benigna, com recuperacao completa, ilustra que a sindrome de Balint pode ser devida a alteracoes funcionais reversiveis do cortex cerebral.

[Experimental surgery of the facial nerve. Evaluation of the intraperitoneal use of exogenous gangliosides]. / Chirurgie expérimentale du nerf facial. Evaluation de l'utilisation intrapéritonéale des gangliosides.

Compression and section of the facial nerve were performed in 48 rats in order to study the anatomopathological alterations occurring after daily intraperitoneal injections of 100 mg of exogenous gangliosides (Sinaxial) for 45, 90, 180 days. In groups submitted to nerve compression, the histopathological changes were discrete and in the 180-day subgroups the nerve was practically normal. In animals submitted to section and neurorrhaphy there was formation of an amputation neuroma, a granuloma around the suture, axonal unstructuration and inter and perineural fibrosis. No significant differences were observed between the groups submitted or not to injection of exogenous gangliosides, indicating that the major factors involved in the quality of nerve regeneration were the technique and the formation of fibrosis and of an amputation neuroma.