Otolaryngology Commons^™

Epidermal Growth Factor Mediated Healing In Stem Cell-Derived Vocal Fold Mucosa, Liliana Palencia, Amritava Das, Sean P. Palecek, Susan L. Thibeault, Ciara Leydon

Communication Disorders Faculty Publications

Background: The goal of vocal fold wound healing is the reconstitution of functional tissue, including a structurally and functionally intact epithelium. Mechanisms underlying reepithelialization in vocal folds are not known, although it is suspected that healing involves the interplay between several growth factors. We used a three-dimensional human embryonic stem cell-derived model of vocal fold mucosa to examine the effects of one growth factor, exogenous epidermal growth factor (EGF), on wound healing. Materials and methods: A scratch wound was created in the in vitro model. Rate of wound healing, epidermal growth factor receptor (EGFR) activation, and cell proliferation after injury …

Epithelial Cells Are Active Participants In Vocal Fold Wound Healing: An In Vivo Animal Model Of Injury, Ciara Leydon, Mitsuyoshi Imaizumi, Rebecca S. Bartlett, Sarah F. Wang, Susan L. Thibeault

Communication Disorders Faculty Publications

Vocal fold epithelial cells likely play an important, yet currently poorly defined, role in healing following injury, irritation and inflammation. In the present study, we sought to identify a possible role for growth factors, epidermal growth factor (EGF) and transforming growth factor-beta 1 (TGFβ1), in epithelial regeneration during wound healing as a necessary first step for uncovering potential signaling mechanisms of vocal fold wound repair and remodeling. Using a rat model, we created unilateral vocal fold injuries and examined the timeline for epithelial healing and regeneration during early and late stages of wound healing using immunohistochemistry (IHC). We observed time-dependent …

Cochlear Development And Auditory Function In The Absence Of Thyroid Hormone Transporters Mct8 And Oatp1c1, Richard Sinn

All Graduate Theses, Dissertations, and Other Capstone Projects

Thyroid hormone (TH) is essential for the development and maturation of the nervous system. The thyroid gland secretes an active form of TH, triiodothyronine, and a prohormone, thyroxine, into the blood. TH is charged, which prevents it from passively diffusing across cell membranes and thus requires cell membrane transporters to facilitate its movement into and out of cells. However, whether TH transporters are required for TH-mediated developmental events, including the auditory system, is largely unknown.

The purpose of the present study was to investigate two specific TH transporters, monocarboxylate transporter 8 (Mct8) and organic anion transporting polypeptide 1c1 (Oatp1c1), and …

Noise-Induced Tinnitus Using Individualized Gap Detection Analysis And Its Relationship With Hyperacusis, Anxiety, And Spatial Cognition, Edward Pace, Jinsheng Zhang

Communication Sciences and Disorders Faculty Research Publications

Tinnitus has a complex etiology that involves auditory and non-auditory factors and may be accompanied by hyperacusis, anxiety and cognitive changes. Thus far, investigations of the interrelationship between tinnitus and auditory and non-auditory impairment have yielded conflicting results. To further address this issue, we noise exposed rats and assessed them for tinnitus using a gap detection behavioral paradigm combined with statistically-driven analysis to diagnose tinnitus in individual rats. We also tested rats for hearing detection, responsivity, and loss using prepulse inhibition and auditory brainstem response, and for spatial cognition and anxiety using Morris water maze and elevated plus maze. We …

Intelligibility Of Electrolarynx Speech Using A Novel Hands-Free Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal excitation. In this paper, the intelligibility of speech produced using a novel hands-free actuator is compared to speech produced using a conventional electrolarynx. Two able-bodied speakers (one male, one female) performed a closed response test containing 28 monosyllabic words, once using a conventional electrolarynx and a second time using the novel design. The resulting audio recordings …

Intelligibility Of Electrolarynx Speech Using A Novel Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. Following a laryngectomy, some people speak using an electrolarynx which replaces the excitatory function of the absent larynx. Drawbacks of conventional electrolarynx designs include the buzzing monotonic sound emitted, the need for a free hand to operate the device, and difficulty experienced by many laryngectomees in adapting to its use. Despite these shortcomings, it remains the preferred method of speech rehabilitation for a substantial minority of laryngectomees. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal …

Cerumen Composition By Flash Pyrolysis-Gas Chromatography/Mass Spectrometry, Craig N. Burkhart, Michael A. Kruge, Craig G. Burkhart, Curtis Black

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Objective: To assess the chemical composition of cerumen by flash pyrolysis-gas chromatography/mass spectrometry.

Study Design: Collected earwax specimens were fractionated into residue and supernatant by means of deoxycholate. This natural bile acid produces significantly better disintegration of earwax in vitro than do presently available ceruminolytic preparations, and also has demonstrated excellent clinical results in vivo to date.

Patients: The sample for analysis was obtained from a patient with clinical earwax impaction.

Results: The supernatant is composed of simple aromatic hydrocarbons, C₅-C_{l 7} straight-chain hydrocarbons, a complex mixture of compounds tentatively identified as diterpenoids, …

Hearing Screening Of Infants Using Evoked Otoacoustic Emissions : The Effect Of External And Middle Ear Conditions, P. K. Vanaja P. K. Krishna Poduval

Student Works (2000-2009)

The aim of the study was to determine if Transient Evoked Otoacoustic Emissions (TEOAEs) can be used as a method of Screening for hearing impairment and to study the effects of External and Middle ear conditions on the outcome of TEOAEs. TEOAE and Tympanometry tests were performed on 193 infants (386 ears). External and Middle ear abnormalities were evaluated by ear examinations and Tympanometry, and assigned to two groups based on the tympanogram results. Group A had normal external and middle ear with 'Type A' Tympanograms and group B with external and/ middle ear abnormalities and abnormal tympanograms other than …

The Effect Of Masking On The Acoustic Reflex Threshold, Nancy E. Aldrich

Loma Linda University Electronic Theses, Dissertations & Projects

This study investigated the effect of masking noise on the threshold for stapedial reflex. It has been shown that masking which shifts the hearing threshold causes a loudness function typical of recruitment. It was hypothesized that the stapedial reflex threshold remains the same in a masked situation as in the unmasked situation . It was suggested that this demonstrates recruitment in that the presence of noise reduces the range between hearing thresholds and stapedial reflex thresholds.

Ten subjects, with no known hearing loss or pathology involving the ear or reflex arc were used in this study. A 1000 Hz tone …