PURPOSE: To investigate the effects of exposure to cigarette and alcohol on immunohistochemical disorders caused by these attacks to respiratory system of rats.METHODS:Sixty male Wistar rats in four groups: control, cigarette smoke, alcohol and cigarette smoke + alcohol during 260 days. Immunohistochemistry was performed by researching survivin and protein P53 expressions and apoptotic index in parenchymal lung and trachea using TUNEL technique.RESULTS: There was body growth impairment in all experimental groups. Both smoker groups animals had higher trachea survivin expression and bronchial higher apoptotic index. The trachea apoptotic index was also higher in the cigarette smoke group as well as in the alveoli in the cigarette smoke + alcohol group. The three experimental groups showed negative immunoexpression for P53.CONCLUSIONS: this model resulted in immunohistochemical changes caused mainly by exposure to cigarette smoke. There was a synergistic action between alcohol and tobacco in the growth impairment in animals as well as in the cellular apoptotic index. The positive immunoexpression for tracheal survivin in animals from both groups exposed to tobacco smoke and associated with a negative P53 immunoexpression suggests that despite the aggression, carcinogenesis has not happened yet. In addition, the bronchial higher apoptotic index in smokers may be responsible for emphysema.

PURPOSE: To obtain a decellularized tracheal scaffold associating traditional approaches with the novel light-emitting diode (LED) proposal.METHODS:This study was performed with New Zealand adult rabbits weighing 3.0 - 4.0 kg. Different protocols (22) were used combining physical (agitation and LED irradiation), chemical (SDS and Triton X-100 detergents), and enzymatic methods (DNase and RNase).RESULTS:Generally, the cells surrounding soft tissues were successfully removed, but none protocol removed cells from the tracheal cartilage. However, longer protocols were more effective. The cost-benefits relation of the enzymatic processes was not favorable. It was possible to find out that the cartilaginous tissue submitted to the irradiation with LED 630nm and 475 nm showed an increased number of gaps without cells, but several cells were observed to be still present.CONCLUSION:The light-emitting diode is a promising tool for decellularization of soft tissues.

OBJECTIVES:Despite the recent success regarding the transplantation of tissue-engineered airways, the mechanical properties of these grafts are not well understood. Mechanical assessment of a tissue-engineered airway graft before implantation may be used in the future as a predictor of function. The aim of this preliminary work was to develop a noninvasive image-processing environment for the assessment of airway mechanics.METHOD:Decellularized, recellularized and normal tracheas (groups DECEL, RECEL, and CONTROL, respectively) immersed in Krebs-Henseleit solution were ventilated by a small-animal ventilator connected to a Fleisch pneumotachograph and two pressure transducers (differential and gauge). A camera connected to a stereomicroscope captured images of the pulsation of the trachea before instillation of saline solution and after instillation of Krebs-Henseleit solution, followed by instillation with Krebs-Henseleit with methacholine 0.1 M (protocols A, K and KMCh, respectively). The data were post-processed with computer software and statistical comparisons between groups and protocols were performed.RESULTS:There were statistically significant variations in the image measurements of the medial region of the trachea between the groups (two-way analysis of variance [ANOVA], p<0.01) and of the proximal region between the groups and protocols (two-way ANOVA, p<0.01).CONCLUSIONS:The technique developed in this study is an innovative method for performing a mechanical assessment of engineered tracheal grafts that will enable evaluation of the viscoelastic properties of neo-tracheas prior to transplantation.