Tracheal reconstruction using alcohol-stored homologous cartilage and autologous cartilage in the rabbit model

Objective: Reconstruction of laryngotracheal stenosis continues to pose a significant challenge. Cartilage grafts have been in use for almost a century, but despite good clinical results, many questions concerning the survival and growth of implanted cartilage persist. To reduce donor site morbidity, the use of homologous cartilage has been investigated. This study compared alcohol-stored homologous auricular cartilage with autologous auricular cartilage for anterior graft laryngotracheal reconstruction in a rabbit model, Methods: Autologous and alcohol preserved homologous auricular cartilage was transplanted to the resected anterior tracheal wall of the twenty New Zealand rabbits. Rabbits were sacrificed 6 weeks after surgery and histologic analysis was performed on the implanted cartilage grafts. Results: The autografts were significantly more likely than the homografts to demonstrate Viable cells (95% vs. 30%, P < 0.05) and less likely to exhibit significant resorption, fibrosis or necrosis (P < 0.05). Resorption and necrosis were most common in areas of trauma to the graft. Complete epithelialization occurred in all of the autografts but in only 65% of the homografts (P < 0.05). New cartilage formation and integration of the implanted grafts was poor with both types of grafts. Conclusion: Autologous cartilage appears to have better survival than alcohol preserved homologous cartilage when used for anterior graft laryngotracheal reconstruction in a rabbit model. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved

Thymosin alpha-1: Evidence for an antiatherogenic effect

In the present study, the effects of thymosin alpha(1) on lipid peroxidation were studied in an in vivo model of experimental hypercholesterolemia. In groups II-IV, rabbits were fed a high-cholesterol diet 2% (w/w) for 10 weeks. Thereafter, rabbits in group III were fed a normal diet for another 14 days and those in group IV were given a normal diet plus 25 mu g/kg thymosin alpha(1) intraperitoneally every other day for the same period. At the end of this period, plasma and erythrocyte lipid levels and susceptibility of erythrocytes to lipid peroxidation were determined in all groups. Hypercholesterolemic rabbits had high plasma and erythrocyte lipid peroxide (TBARS) levels compared to control animals fed a normal diet. Plasma and erythrocyte TEARS levels significantly decreased in the thymosin-alpha 1-injected rabbits. In thymosin-alpha(1)-treated animals (group IV), most of the lipid plaques were replaced by fibrous tissue. These findings suggest that thymosin alpha(1) may have some beneficial effects on the treatment of atherosclerosis by normalizing blood lipid levels and by substantially protecting endothelial cells against free radical injury

The primitive neuroectodermal tumor of the heart

A young man was admitted to hospital with dyspnea, malaise, chest pain and night sweating. Investigative studies revealed a cystic mass lesion originating from the heart. Surgical exploration of the tumor showed that it was unresectable and pathology of the biopsy material was primitive neuroectodermal tumor. Medical literature concerning this unusual type of tumor is reviewed. (C) 2000 Elsevier Science B.V. All rights reserved

Craniopharyngioma extended into the posterior fossa

A 7-year-old girl with a craniopharyngioma with a rare extension into the posterior fossa is presented. MRI revealed a solid calcified mass in the sellar and suprasellar region with a cyst expanded to the posterior fossa up to the foramen magnum and causing hydrocephalus and brainstem displacement. The tumor was removed totally with right pterional approach