Lung morphology and growth of rats exposed to tobacco smoke and alcohol / Estudo morfológico dos pulmões e crescimento de ratos expostos à fumaça do cigarro e ao álcool

PURPOSE: Investigate the morphological effects of chronic exposure to tobacco smoke inhalation and alcohol consumption on the lungs and on the growth of rats. METHODS: Sixty male Wistar rats were divided into four groups: control, tobacco, alcohol, tobacco + alcohol, for a period of study 260 days. Morphological analysis was conducted by optical and electron microscopy. Rat growth was investigated by measuring the snout-anus length, body mass index and body weight. RESULTS: The three groups exposed to the drugs presented lower growth and lower weight than the control group. The percentages of alveolitis, bronchiolitis and the mean alveolar diameter were greater, particularly in the groups exposed to tobacco smoke, but were not significantly different from the control group. Electron microscopy revealed more intense apoptotic and degenerative lesions in the smoking group, while degenerative lesions in the lamellar bodies were more intense with the association of both drugs. CONCLUSIONS: This experimental model showed morphological alterations observed by electron microscopy, principally due to tobacco smoke exposure. Alcohol and tobacco hindered the growth of rats, such that tobacco showed a greater effect on body length and alcohol on body weight.(AU)

OBJETIVO: Investigar os efeitos morfológicos da exposição crônica à inalação de fumaça do tabaco e o do consumo de álcool nos pulmões e no crescimento de ratos. MÉTODOS: Sessenta ratos Wistar machos foram distribuídos em quatro grupos: controle, tabaco, álcool e tabaco + álcool, e acompanhados por um período de 260 dias. No final do periodo foi realizada análise morfológica dos pulmões por microscopia óptica e eletrônica. O crescimento dos ratos foi investigado através da medição do comprimento focinho-ânus, peso corporal e índice de massa corporal. RESULTADOS: Os três grupos expostos às drogas apresentaram peso e comprimento significativamente menores que os do grupo controle. As percentagens de bronquiolite e alveolite, e o diâmetro alveolar médio foram maiores nos grupos expostos à fumaça do tabaco, mas sem significancia estatística quando comparadas ao grupo controle. A microscopia eletrônica revelou apoptose mais intensa e lesões degenerativas no grupo de fumantes, enquanto lesões degenerativas nos corpos lamelares foram mais intensas com a associação de ambas as drogas. CONCLUSÕES: Este modelo experimental mostrou alterações morfológicas observadas por microscopia eletrônica, principalmente devido à exposição ao tabaco. Tanto o alcool como o tabaco prejudicaram o crescimento dos animais, o tabaco mostrando um efeito maior sobre o comprimento e o álcool sobre o peso corporal.(AU)

Morphological findings in the tracheal epithelium of dogs exposed to the inhalation of poorly conditioned gases under use of an endotracheal tube or laryngeal mask airway / Alterações morfológicas no epitélio traqueal de cães expostos à inalação de gases pouco condicionados, sob ventilação com tubo traqueal ou máscara laríngea

PURPOSE: To study morphological findings in the tracheal epithelium of dogs exposed to the inhalation of poorly conditioned gases under use of an endotracheal tube (ET) or laryngeal mask airway (LMA). METHODS: Twelve dogs randomly were allocated to two groups: ET group (n-6) and LMA group (n-6), anaesthetized and mechanically ventilated, without CO2 reabsorption. Haemodynamic and ventilatory parameters, tympanic temperature, temperature, relative and absolute humidity of the ambient and inhaled gases were analyzed during three hours. The animals were submitted to euthanasia and biopsies were carried out along the tracheal segment to morphological study. Three healthy dogs were used to morphological control. RESULTS: Inhaled gas temperature was maintained between 24ºC and 26ºC, relative humidity between 10% and 12%, and absolute humidity between 2 - 3 mg H2O.L-1 with no significant differences between groups. In both groups, histological analysis showed epithelial inflammation and congestion in the corion and scanning electron microscopy showed ciliary grouping and disorganization. Transmission electron microscopy showed higher alterations in ET group than LMA group as widening of cell junctions, ciliary disorientation, cytoplasmic vacuolization, nuclear abnormalities, picnosis and chromatin condensation. CONCLUSION: LMA determined less pronounced changes in the tracheal epithelium in dogs exposed to the inhalation of poorly conditioned gases.(AU)

OBJETIVO: Avaliar as alterações morfológicas no epitélio traqueal de cães expostos à inalação de gases pouco condicionados, sob ventilação com tubo traqueal (TT) ou máscara laríngea (ML). MÉTODOS: Doze cães adultos foram divididos aleatoriamente em dois grupos: grupo TT (n-6) e grupo ML (n-6), submetidos à anestesia venosa e ventilação mecânica, em sistema sem reabsorção de CO2. Foram registrados parâmetros hemodinâmicos e ventilatórios, temperatura timpânica, temperatura, umidade relativa e absoluta do ar ambiente e dos gases inalados durante 3 horas. Ao término do experimento, os animais foram submetidos a eutanásia e realizadas biópsias ao longo do segmento traqueal para estudo morfológico. Três cães saudáveis foram utilizados para controle morfológico. RESULTADOS: A temperatura dos gases inalados manteve-se entre 24ºC e 26ºC, a umidade relativa entre 10% e 12%, e umidade absoluta entre 2 -3 mg H2O.L-1 sem diferença significativa entre os grupos. Em ambos os grupos a análise histológica evidenciou processo inflamatório epitelial e congestão no córion, e a microscopia eletrônica de varredura mostrou agrupamento e desorganização ciliar. A microscopia eletrônica de transmissão detectou maiores alterações no grupo TT do que no ML, como alargamento das junções intercelulares, desorientação ciliar, vacuolização citoplasmática, alterações nucleares como pcinose e condensação da cromatina. CONCLUSÃO: A máscara laríngea determinou alterações menos pronunciadas no epitélio traqueal de cães expostos à inalação de gases pouco condicionados.(AU)

The relationship between suture number and the healing process of end-to-end arterial anastomosis

In spite of the grate experience accumulated in vascular repairing, the ideal number of sutures for vascular anastomosis remains controversial. It is generally thought that the more stitches applied in a vascular anastomosis, the lesser resistant the anastomosis will be. The purpose of this study was to test this hypothesis in 20 rabbits, in which both carotid arteries were cross sectioned and repaired by end-to-end anastomosis with 8 interrupted sutures in one side (G1) and 16 in the other side (G2). After 3 and 15 days, the animals were randomly allocated for tensile strength, hydroxyproline determination (7 animals) and for histologic analysis of the anastomosis (3 animals). Conventional staining procedures (hematoxylin-eosin and Masson methods) and the picrosirius red polarization (PSP) technique for collagen type determination were used. From 3 to 15 days, the tensile strength increased in both groups, from 265.0±-44.4g to 391.2±-49.0g in G1 and from 310.0±-71.5g to 348.7±-84.0g in G2 (p 0.005), with no statistical difference between the groups in each period of study. The hydroxyproline content, expressed as hydroxyproline/protein ratio, varied from 0.04±-0.01 to 0.05±-0.02 in G1 and from 0.05±-0.01 to 0.05±-0.02 in G2, with no significant difference between periods and groups. The histology showed similar inflammatory and reparative aspects in both groups. In both groups and periods the PSP technique demonstrated predominantly type I collagen in relation to type III collagen in the anastomosis. We concluded that even doubling the number of stitches, the healing process and strength did not change in the arterial anastomosis.