RESUMEN
Acute viral respiratory infections are commonly associated with alterations in lung growth. Recently, fractal techniques have been demonstrated to show changes in alveolar perimeter after canine adenovirus type 2 (CAV2) infection in a beagle puppy model. In the present study, we investigated whether the fractal dimension (Df) of the alveolar perimeter was changed in the acute phase (2-3 weeks after inoculation, 131d CAV2 group) or during the recovery phase (approximately 22 weeks after inoculation, 235d CAV2 group) after a single bout of CAV2. There were sham CAV2 groups, 130d and 238d controls, corresponding to the CAV2 groups. The Df of alveolar perimeter length was significantly increased in the 235d CAV2 puppies compared to all of the other beagle puppy groups. On the other hand, the fractal dimensions for alveolar perimeter length for the other beagle puppy groups were very similar. In a related human study of patients (age range of 25 h to 19 y, N = 11), who died of non-respiratory causes, showed no consistent change in Df of alveolar perimeter length with normal lung growth and development. We conclude that fractal analysis of alveolar perimeter length can be used as an index of permanent lung injury after insult to the growing lungs.
Asunto(s)
Infecciones por Adenoviridae/patología , Adenovirus Caninos/fisiología , Alveolos Pulmonares/patología , Enfermedad Aguda , Infecciones por Adenoviridae/fisiopatología , Adolescente , Adulto , Análisis de Varianza , Animales , Autopsia , Niño , Preescolar , Convalecencia , Modelos Animales de Enfermedad , Perros , Femenino , Fractales , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Recién Nacido , Masculino , Embarazo , Alveolos Pulmonares/crecimiento & desarrollo , Alveolos Pulmonares/ultraestructura , Alveolos Pulmonares/virologíaRESUMEN
We have determined that fractal analysis of the alveolar perimeter (Df) changes with aging in human lung tissue in twenty-nine patients, age range of 25 hours to 76 years, who died of non-respiratory related causes. There was a very significant difference (p = 0.0004) in Df between the young (less than 16 years old, N = 9, mean Df of 1.047 [0.01]) and adult (greater than 16 years old, N = 20, mean Df of 1.093 [0.013]) groups. Furthermore, there was a significant difference in Df between the Adult group and the group of patients who died of chronic obstructive pulmonary disease (COPD, N = 10) (p = 0.012). Additionally, the Df values for the COPD and cystic fibrosis (CF, N = 5) groups were virtually identical; 1.061 and 1.070, respectively. Regression analysis showed a significant (p = 0.0041) exponential relationship with a correlation coefficient of 0.59 between aging and Df. We have demonstrated that the correlation between Df and aging in humans is an exponential function and that the end-stage pulmonary diseases of COPD and CF decrease Df.