7 resultados para enucleation

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Ocular enucleation produces significant morphological and physiological changes in central visual areas. However, our knowledge of the molecular events resulting from eye enucleation in visual brain areas remains elusive. We characterized here the transcription nuclear factor kappa-B (NF-kappa B) activation induced by ocular enucleation in the rat superior colliculus (SC). We also tested the effectiveness of the synthetic glucocorticoid dexamethasone in inhibiting its activation. Electrophoretic mobility shift assays to detect NF-kappa B indicated that this transcription factor is activated in the SC from 1 h to day 15 postlesion. The expression of p65 and p50 proteins in the nuclear extracts was also increased. Dexamethasone treatment was able to significantly inhibit NF-kappa B activation. These findings suggest that this transcriptional factor is importantly involved in the visual system short-term processes that ensue after retinal lesions in the adult brain. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

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Ocular enucleation induces profound morphological alterations in central visual areas. However, little is known about the response of glial cells and possible inflammatory processes in visual brain areas resulting from eye enucleation. In this study, immunoblotting and immunostaining assays revealed increased expression of astrocyte and microglia markers in the rat superior colliculus (SC) between 1 and 15 days after contralateral enucleation. A transient increase of neuronal COX-2 protein expression was also found in the SC. To evaluate the role of an anti-inflammatory drug in attenuating both COX-2 and glial cell activation, the synthetic glucocorticoid dexamethasone (DEX) was administered (1mg/kg i.p., for 3 days) to enucleated rats. Immunoblotting data revealed that DEX treatment significantly inhibited COX-2 protein expression. Postlesion immunostaining for astrocyte and microglia markers was also significantly reduced by DEX treatment. These findings suggest that the removal of retinal ganglion cell input generates inflammatory responses in central retinorecipient structures

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We describe a case of retinoblastoma with an atypical presentation and previously unreported cytogenetic aberrations. A 19-month-old girl with left intraocular retinoblastoma was treated with enucleation and chemotherapy. The disease showed aggressive evolution within a short period between diagnosis and relapse. Eight months after diagnosis, a new large tumor was present in the orbit of the right eye, with diffuse bone pain, pancytopenia and diffuse infiltration into the bone marrow and the central nervous system. The child did not respond to treatment and died. Cytogenetic studies made with G-banding, FISH and SKY analysis showed chromosomal aberrations commonly associated with retinoblastoma, including del(13q), i(6+1, and monosomy 16, along with others that had not been reported previously, including dup(5q), dic(15;22) and add(14q). The new chromosomal aberrations may be related to the aggressiveness of the disease in this case.

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Keratocystic odontogenic tumor is characterized by high recurrence rates. Conservative or aggressive management has been suggested as a method of treatment. Decompression is a conservative treatment that has been used in the treatment of large odontogenic cysts. The authors report a case of a 14-year-old patient with a keratocystic odontogenic tumor located in the right maxilla, which was treated by decompression followed by enucleation with curettage. The lesion did not recur on follow-up for 3 years after the enucleation surgery.

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Oral Diseases (2012) 18, 548557 Objective: Keratocystic odontogenic tumors (KOTs) can be treated with Carnoys solution, although this treatment modality is not free from complications. It is important to verify the incidence of complications after the use of Carnoys solution and compare these with the literature. Materials and methods: This study verified the effects of a complementary treatment for KOTs and assessed the incidence of such complications as recurrence, infection, sequestrum formation, mandibular fracture, dehiscence, and neuropathy. Results: Twenty-two KOTs treated with Carnoys solution combined with peripheral ostectomy were included, and the follow-up period varied from 12 to 78 months with a mean of 42.9 months. Complications included recurrence (4.5%), dehiscence (22.7%), infection (4.5%), and paresthesia (18.2%). No difference was found among lesions associated (9.1%) or not (0%) with nevoid basal cell carcinoma syndrome (P > 0.05). Dehiscence was influenced by marsupialization (P < 0.05), and paresthesia was observed exclusively in cases of mandibular canal fenestration (P < 0.01). Conclusions: Complementary treatment with Carnoys solution and peripheral ostectomy appear to provide efficient treatment for KOTs. Complications originating from the use of the solution are less frequent and less serious than complications associated with cryotherapy. Neuropathy seems to be related to direct contact between the solution and the epineurium.

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PURPOSE. Vascular endothelial growth factor (VEGF) is an important signal protein in vertebrate nervous development, promoting neurogenesis, neuronal patterning, and glial cell growth. Bevacizumab, an anti-VEGF agent, has been extensively used for controlling pathological retinal neovascularization in adult and newborn patients, although its effect on the developing retina remains largely unknown. The purpose of this study was to investigate the effect of bevacizumab on cell death, proliferation, and differentiation in newborn rat retina. METHODS. Retinal explants of sixty 2-day-old Lister hooded rats were obtained after eye enucleation and maintained in culture media with or without bevacizumab for 2 days. Immunohistochemical staining was assessed against proliferating cell nuclear antigen (PCNA, to detect cell proliferation); caspase-3 and beclin-1 (to investigate cell death); and vimentin and glial fibrillary acidic protein (GFAP, markers of glial cells). Gene expressions were quantified by real-time reverse-transcription polymerase chain reaction. Results from treatment and control groups were compared. RESULTS. No significant difference in the staining intensity (on immunohistochemistry) of PCNA, caspase-3, beclin-1, and GFAP, or in the levels of PCNA, caspase-3, beclin-1, and vimentin mRNA was observed between the groups. However, a significant increase in vimentin levels and a significant decrease in GFAP mRNA expression were observed in bevacizumab-treated retinal explants compared with controls. CONCLUSIONS. Bevacizumab did not affect cell death or proliferation in early developing rat retina but appeared to interfere with glial cell maturation by increasing vimentin levels and downregulating GFAP gene expression. Thus, we suggest anti-VEGF agents be used with caution in developing retinal tissue. (Invest Ophthalmol Vis Sci. 2012;53:7904-7911) DOI:10.1167/iovs.12-10283

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Surgical approaches to pancreatic endocrine tumors associated with multiple endocrine neoplasia type 1 may differ greatly from those applied to sporadic pancreatic endocrine tumors. Presurgical diagnosis of multiple endocrine neoplasia type 1 is therefore crucial to plan a proper intervention. Of note, hyperparathyroidism/multiple endocrine neoplasia type 1 should be surgically treated before pancreatic endocrine tumors/multiple endocrine neoplasia type 1 resection, apart from insulinoma. Non-functioning pancreatic endocrine tumors/multiple endocrine neoplasia type 1 >1 cm have a high risk of malignancy and should be treated by a pancreatic resection associated with lymphadenectomy. The vast majority of patients with gastrinoma/multiple endocrine neoplasia type 1 present with tumor lesions at the duodenum, so the surgery of choice is subtotal or total pancreatoduodenectomy followed by regional lymphadenectomy. The usual surgical treatment for insulinoma/multiple endocrine neoplasia type 1 is distal pancreatectomy up to the mesenteric vein with or without spleen preservation, associated with enucleation of tumor lesions in the pancreatic head. Surgical procedures for glucagonomas, somatostatinomas, and vipomas/ multiple endocrine neoplasia type 1 are similar to those applied to sporadic pancreatic endocrine tumors. Some of these surgical strategies for pancreatic endocrine tumors/multiple endocrine neoplasia type 1 still remain controversial as to their proper extension and timing. Furthermore, surgical resection of single hepatic metastasis secondary to pancreatic endocrine tumors/multiple endocrine neoplasia type 1 may be curative and even in multiple liver metastases surgical resection is possible. Hepatic trans-arterial chemo-embolization is usually associated with surgical resection. Liver transplantation may be needed for select cases. Finally, pre-surgical clinical and genetic diagnosis of multiple endocrine neoplasia type 1 syndrome and localization of multiple endocrine neoplasia type 1related tumors are crucial for determining the best surgical strategies in each individual case with pancreatic endocrine tumors.