[The pulmonary surfactant status in lung immaturity]. / Sostoianie surfaktanta legkikh pri ikih nezrelosti.

Combined study of lungs of 85 foetuses and newborns of various gestational age and 8 newborns dying during the first month of life showed the lung surfactant (LS) system to develop in parallel with formation of respiratory parts and lung capillary network. The level of the LS surface activity increases with the increase of the duration of pregnancy and is determined by the maturation degree of the type II alveolocytes. Changes of the surface activity of the lung extract surface-active fraction in the process of lung maturation correlate with the fractional phospholipid distribution. Morphofunctional immaturity of lungs is characterized, besides histological features, by the ultrastructural immaturity of the type II alveolocytes and biochemical immaturity of LS.

[Surfactant surface activity and ultrastructural changes in the type-II alveolocytes of fetal and neonatal lungs in experimental inflammation of the maternal lungs]. / Sostoianie poverkhnostnoi aktivnosti surfaktanta i izmeneniia ul'trastruktury al'veolotsitov II tipa legkikh plodov i novorozhdennykh pri vospalenii legkikh materi v éksperimente.

The lungs of 19 guinea pigs, born from 8 females in which acute and chronic pneumonia had been modelled by transtracheal introduction of sterile fishing-line were investigated. It was established, that in guinea pigs, born in females with acute and chronic pneumonia, the functional immaturity of pneumocytes of the 2-nd type took place. The functional immaturity of pneumocytes of the 2-nd type results in suppression of the surface active characteristics of surfactant.