title: Design and validation of a bioreactor for engineering vocal fold tissues under combined tensile and vibrational stresses.
abstract: Criteria are outlined for the design of a bioreactor that can simulate the vibrational stresses in vocal fold movement during speech. Requirements are 0-1 mm amplitudes in the 20-200 Hz frequency range, a variable on-off stress regime, and maintenance of tissue viability over several days. The bioreactor uses dual drivers, one for low frequency (or static) strains, and another for high-frequencies vibrational strains. Response is linear at the driving end for an input of 0-5 V. The amplitude decreases linearly with frequency at constant input voltage, and the phase changes by nearly 180 degrees over the 20-200 Hz range. Human vocal fold fibroblasts were cultured in a polymer substrate and subjected to static and vibrational forces. The results indicate that vibratory strain alters the expression levels of many extracellular matrix-related genes, as well as the spatial distribution of cells and matrix.
authors.affiliation: Department of Speech Pathology and Audiology, The University of Iowa, Iowa City, IA 52242, USA.
authors.forename: Ingo R
authors.initials: IR
authors.lastname: Titze
authors.forename: Robert W
authors.initials: RW
authors.lastname: Hitchcock
authors.forename: Kelly
authors.initials: K
authors.lastname: Broadhead
authors.forename: Ken
authors.initials: K
authors.lastname: Webb
authors.forename: Wenhua
authors.initials: W
authors.lastname: Li
authors.forename: Steven D
authors.initials: SD
authors.lastname: Gray
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Tresco
mesh_terms: D019149:Bioreactors; D002470:Cell Survival; D002478:Cells, Cultured; D004594:Electrophysiology; D004867:Equipment Design; D005109:Extracellular Matrix / Q000235:genetics / Q000502:physiology; D005347:Fibroblasts / Q000502:physiology; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D007830:Larynx / Q000502:physiology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger; D015203:Reproducibility of Results; D013312:Stress, Physiological / Q000503:physiopathology; D023822:Tissue Engineering; D014732:Vibration; D014827:Vocal Cords / Q000502:physiology*
chemical_list: D012333:RNA, Messenger