title: [Biophysical models in investigations of exogenous surfactant activities on the surface tension and their theurapeutic effectiveness].
abstract: Surfactant therapy leads to significant clinical improvement in infants at risk for, or having, respiratory distress syndrome (RDS). The development of exogenous surfactant (ES) as a therapy for neonatal respiratory disorders was a significant advance in neonatal intensive care that has led to a decrease in neonatal mortality. Two broad categories of surfactants are available for exogenous therapy: surfactants derived from animal sources or 'natural' surfactants; and synthetic surfactants. The physical properties of natural and synthetic surfactants have been studied using techniques such as the Wilhelmy surface balance and the bilayer black film (BBF) method. Here we report some data from a comparative study of ES (Exosurf, Survanta, Curosurf and Alveofact) and clinical samples of tracheal aspirate (TA) of newborns with RDS treated with Curosurf. Measured interfacial physico-chemical parameters prove "better" properties in vitro of the surfactant proteins (SP-B and SP-C) containing preparations Curosurf and Alveofact. Their properties are similar, Alveofact showing a higher surface tension lowering capacity under dynamic conditions. A compendious comparison of results for dynamic surface properties of monolayers of TA from newborns treated with Curosurf with data for newborns treated with Exosurf is presented. Both ES yield the desired lowering of the surface tension during cyclic film compression, being larger after treatment with Curosurf. Observations concerning the properties of BFF of ES (dependence on surfactant concentration, adsorption time, film drainage time and BFF formation time) are also reported and discussed.
authors.forename: R
authors.initials: R
authors.lastname: Todorov
authors.forename: A
authors.initials: A
authors.lastname: Iordanova
authors.forename: G A
authors.initials: GA
authors.lastname: Georgiev
authors.forename: Kh
authors.initials: Kh
authors.lastname: Petkova
authors.forename: E
authors.initials: E
authors.lastname: Stoimenova
authors.forename: R
authors.initials: R
authors.lastname: Georgieva
authors.forename: E
authors.initials: E
authors.lastname: Khristova
authors.forename: Kh
authors.initials: Kh
authors.lastname: Vasiliev
authors.forename: Z
authors.initials: Z
authors.lastname: Lalchev
mesh_terms: D000818:Animals; D001688:Biological Products / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D055592:Biophysical Phenomena; D001703:Biophysics; D004338:Drug Combinations; D005233:Fatty Alcohols / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007231:Infant, Newborn; D008055:Lipids / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D008954:Models, Biological; D010743:Phospholipids / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D010767:Phosphorylcholine / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D011092:Polyethylene Glycols / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D011663:Pulmonary Surfactants / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D012127:Respiratory Distress Syndrome, Newborn / Q000188:drug therapy* / Q000378:metabolism; D013500:Surface Tension / Q000187:drug effects
chemical_list: D001688:Biological Products; D004338:Drug Combinations; D005233:Fatty Alcohols; D008055:Lipids; D010743:Phospholipids; D011663:Pulmonary Surfactants; C078272:SF-RI 1, bovine surfactant preparation; D010767:Phosphorylcholine; D011092:Polyethylene Glycols; C047049:dipalmitoylphosphatidylcholine, hexadecanol, tyloxapol drug combination; C068291:poractant alfa; C072197:beractant