Audiology in Brief A new animal model study provides new insights into how noise damages the stereocilia bundles in ears and how that damage can be repaired. Researchers at the National Institute on Deafness and Other Communication Disorders found that when mice are exposed to loud sounds, gaps form in the stereocilia ... News in Brief
Free
News in Brief  |   August 01, 2009
Audiology in Brief
Author Notes
Article Information
Hearing Disorders / Special Populations / Early Identification & Intervention / News in Brief
News in Brief   |   August 01, 2009
Audiology in Brief
The ASHA Leader, August 2009, Vol. 14, 5. doi:10.1044/leader.NIB.14102009.5
The ASHA Leader, August 2009, Vol. 14, 5. doi:10.1044/leader.NIB.14102009.5
Protein Patches Up Noise-Induced Damage
A new animal model study provides new insights into how noise damages the stereocilia bundles in ears and how that damage can be repaired. Researchers at the National Institute on Deafness and Other Communication Disorders found that when mice are exposed to loud sounds, gaps form in the stereocilia bundles like giant potholes on a street. If not repaired, the gaps grow, degrading the stereocilia and causing permanent hearing loss.
The research team was surprised to learn that a protein, gamma-actin, helps fill the stereocilia bundle gaps caused by excessive noise levels, while a second, closely related protein, beta-actin, is responsible for building the structures in the first place. In the absence of gamma-actin, beta-actin does not efficiently repair or prevent further damage to the stereocilia.
The researchers were the first to develop a mouse in which the gamma-actin gene was knocked out, rendering it unable to produce the protein. Because gamma-actin is found in all cells in the body, scientists believed that an animal without the protein would not survive. However, the research found not only did some of the genetically altered mice live, but also that their hearing was normal at 6 weeks of age, when a mouse’s hearing is fully matured. However, by 24 weeks, the mice had profound hearing loss. Visit the June 16 issue of the Proceedings of the National Academy of Sciences (Vol. 106, No. 24).
Newborn Hearing Screening Loss to Follow-up
Are newborns screened for hearing being fit with hearing aids by 6 months? Researchers at the Long Island Jewish Medical Center in New York examined the screening and follow-up records of 114, 121 infants over a six-year period. They found that 91% of referred infants returned for follow-up evaluation. Hearing aids were fit on 107 of the 192 infants. Of these, 39% were fit by age 6 months and 61% were fit later or lost to follow-up. Factors associated with loss to follow-up included unilateral hearing loss, late diagnosis, conductive hearing loss, and Medicaid coverage. This article in the June 2009 issue of the American Journal of Audiology is offered for CEUs.
Good at Explaining Audiograms?
The audiogram: Is it objective data that helps people understand their hearing loss or a bewildering series of lines and circles? The Ida Institute invites hearing care professionals to share their successful approaches to helping patients and families understand and appreciate the audiogram. The best submission will win a free trip to an institute seminar in Denmark.
To enter, submit a script or description of the approach (not to exceed two typed pages), to shn@idainstitute.dk. The Ida Institute, an independent, educational non-profit near Copenhagen, is funded by a grant from the Oticon Foundation. For more information, search “contest” on the Ida Institute’s Web site.
0 Comments
Submit a Comment
Submit A Comment
Name
Comment Title
Comment


This feature is available to Subscribers Only
Sign In or Create an Account ×
FROM THIS ISSUE
August 2009
Volume 14, Issue 10