Pulmonary surfactant-associated proteins (SP-B) promote alveolar stability by lowering the surface tension at the air-liquid interface in the peripheral air spaces. SP-B increases the collapse pressure of palmitic acid to nearly 70 millinewtons per meter. Genetic variations in SP-B are a cause of susceptibility to respiratory distress syndrome in premature infants (RDS). RDS is a lung disease affecting usually premature newborn infants. It is characterized by deficient gas e, Xenopus/Amphibian,change, diffuse atelectasis, high-permeability lung edema and fibrin-rich alveolar deposits called 'hyaline membranes'.