title: Real-time study of shape and thermal fluctuations in the echinocyte transformation of human erythrocytes using defocusing microscopy.
abstract: We present a real-time method to measure the amplitude of thermal fluctuations in biological membranes by means of a new treatment of the defocusing microscopy (DM) optical technique. This approach was also applied to study the deformation of human erythrocytes to its echinocyte structure. This was carried out by making three-dimensional shape reconstructions of the cell and measuring the thermal fluctuations of its membrane, as the cell is exposed to the anti-inflammatory drug naproxen and as it recovers its original shape, when it is subsequently cleansed of the drug. The results showed biomechanical changes in the membrane even at low naproxen concentration (0.2 mM). Also, we found that when the cell recovered its original shape, the membrane properties were different compared to the nondrugged initial erythrocyte, indicating that the drug administration-recovery process is not completely reversible.
authors.affiliation: Center for Optics and Photonics, Universidad de Concepción, Concepción, Chile. setcheverry@udec.cl
authors.forename: Sebastián
authors.initials: S
authors.lastname: Etcheverry
authors.forename: María José
authors.initials: MJ
authors.lastname: Gallardo
authors.forename: Pablo
authors.initials: P
authors.lastname: Solano
authors.forename: Mario
authors.initials: M
authors.lastname: Suwalsky
authors.forename: Oscar N
authors.initials: ON
authors.lastname: Mesquita
authors.forename: Carlos
authors.initials: C
authors.lastname: Saavedra
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D048430:Cell Shape; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000473:pathology / Q000502:physiology*; D004912:Erythrocytes / Q000166:cytology* / Q000473:pathology / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008853:Microscopy / Q000379:methods*; D009288:Naproxen / Q000494:pharmacology; D013696:Temperature
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D009288:Naproxen