SFTPB and newborn respiratory distress syndrome: At captive bubble surfactometry, adsorption of both canine SP-C ion-lock peptides mixed in surfactant lipids with or without the SP-B peptide mimic B-YL was similar to B-YL alone and to the clinical porcine surfactant Curosurf that contains both native SP-B and SP-C and is one of the leading animal-derived surfactants used in the treatment of premature infants with neonatal respiratory distress syndrome due to surfactant deficiency as a result of lung immaturity.