NIDCD-Supported Research on Stem Cells and Hearing Loss, Music
through the Cochlear Implant and a Virtual Grocery Store for People
with Balance Disorders Featured at ARO Conference in Phoenix
What: Current research supported by the National Institute on
Deafness and Other Communication Disorders (NIDCD), one of the
National Institutes of Health, will be featured at the 2008 Midwinter
Meeting of the Association for Research in Otolaryngology (ARO).
When: February 16-21, 2008
Where: Phoenix Convention Center, Phoenix, Ariz.
Additional Information: Research topics to be presented by NIDCD-
funded scientists will include:
State of the Science: Will Stem Cells Cure Hearing Loss Some Day?
Every time you cut your finger or burn your tongue, new cells are
produced that are able to restore things to normal. So why can't the
same happen for the tiny sensory cells in our inner ear, called hair
cells, that translate sound into electrical signals? If they are
damaged in humans — through disease, too much noise or certain
medicines — they can't be regenerated. In this presentation, NIDCD-
funded scientist Stefan Heller, Ph.D., Stanford University, describes
two areas of exploration in which researchers are trying to grow new
hair cells. He'll report on where the science currently stands in the
differentiation of mouse and human stem cells into hair cells and the
development of drug treatments that could one day be used to
stimulate hair cell growth. The symposium presentation "Cochlear Hair
Cell and Neuronal Regeneration — from the Culture Dish into the
Animal" takes place Monday, February 18, 8:40 a.m. MST, West 101 A-C.
Beyond Words — Helping Cochlear Implant Wearers Listen to the Music
Cochlear implants have brought a sense of sound to more than 100,000
deaf and hard-of-hearing people worldwide, yet music perception
remains a source of frustration for many implant users. To better
understand the problem, researcher Jay Rubinstein, M.D., Ph.D., and
others from the University of Washington have developed the Clinical
Assessment of Music Perception (CAMP) test, an easy-to-use computer
tool designed to help clinicians assess a cochlear implant wearer's
ability to discriminate pitch progression, melody and the source of
the musical tones, whether it's a guitar, harmonica or flute. In this
presentation, Dr. Rubinstein's research team present data from one
commercially funded multicenter study, plus results from additional
research in his laboratory, in which CAMP is used to assess music
perception in people who wear cochlear implants. In this same
workshop, rock-and-roll and R&B musician and cochlear implant wearer
Richard Reed conducts a first-hand demonstration of what music sounds
like through a cochlear implant. The workshop session "Music Lost
and Found" (Reed) takes place Sunday, February 17, 7:50 p.m. MST,
West 301 A. The session "Music Perception with Cochlear Implants"
(Rubinstein et al) takes place at 8:20 p.m. in the same location.
How Background Noise Affects Language-Learning Skills in Kids with
Cochlear Implants
Understanding what someone is saying in a roomful of talkers is
difficult enough for a person with normal hearing. Researchers at the
University of Wisconsin wanted to find out how such an environment
might affect toddlers fitted with cochlear implants who are
developing their language skills. Comparing children with normal
hearing to children with one or two cochlear implants, the
researchers tested the children's ability to identify spoken words in
quiet environments and environments in which people were talking in
the background. Children with normal hearing performed very well in
the quiet environment, though their ability declined when there was
background noise. Children with cochlear implants were not as
accurate as the children with normal hearing in recognizing speech in
both quiet and noisy environments. In addition, children with
cochlear implants took much longer at identifying speech, regardless
of the presence of background noise. These data may provide insight
into how young children who use cochlear implants develop their
language skills. The podium session "The Effect of Competing Noise on
Spoken Word Recognition in Toddlers Who Use Unilateral or Bilateral
Cochlear Implants" takes place Wednesday, February 20, 3:15 p.m. MST,
West 101 A-C.
Researchers Use Common Hearing Test to Explore Link Between Iron
Deficiency and Cognitive Impairments
Iron deficiency is the most common nutritional disorder, affecting
more than two billion people worldwide. It is especially prevalent in
young children and women during their childbearing years. Infants who
are iron-deficient often experience learning problems and other
cognitive impairments, yet the underlying mechanism is unclear.
Researchers at the University of Rochester Medical Center have found
that rat embryos that were deficient in iron very early in their
development exhibited a significant loss of myelin, a protein that
surrounds nerve fibers of the central nervous system and helps speed
the rate by which electrical signals travel along a nerve fiber. This
loss of myelin is associated with slower auditory brainstem responses
(ABRs), a non-invasive measure of the time it takes for sounds played
into the ear to travel along the auditory nerve to the brain. The
researchers find that ABR technology is a useful tool for diagnosing
the loss of myelin along the auditory nerve and for pinpointing the
window of time when iron deficiency is most damaging to the
developing brain. Based on this animal model, the researchers
propose that cognitive impairments found in iron-deficient children
could in part be due to defects in auditory processing and
consequently language acquisition. The poster session "Non-Invasive
Strategy to Characterize the Impact of Gestational Iron Deficiency on
Auditory Nerve Myelination" takes place Tuesday, February 19, 1:00
p.m. MST (48 hours), West 301 B-D.
Virtual Grocery Store Could Help People with Balance Problems
To someone with a balance disorder, a trip to the grocery can be a
dizzying experience. Walking the aisles can be difficult when
scanning store shelves for one product amidst an array of fruit roll-
ups, frozen waffles and fabric softeners. Researchers from the
University of Pittsburgh are using virtual reality to learn more
about the issue. In this clinical study, they asked volunteers with
and without balance problems to shop for two products in a simulated
grocery aisle while walking on a treadmill. The purpose was to
determine if their ability to complete the task correlated with other
clinical measures of balance. The researchers found a moderate to
strong relationship between the volunteers' performance in the
simulated store compared with other measures. The researchers hope to
determine if virtual reality can be used as a therapeutic tool to
help people recover from dizziness and balance problems. The poster
session "Relationship Between Clinical Measures and Performance in a
Virtual Grocery Store Environment in Persons with Vestibular
Dysfunction" takes place Sunday, February 17, 1:00 p.m. MST (48
hours), West 301 B-D.
Combination Hormone Replacement Therapy Increases Risk of Hearing Loss
As we age, our hormone levels decline, often resulting in hormonal
imbalances. This is especially true in women who are going through
menopause. To counter these occurrences, some women use hormone
replacement therapy (HRT), a type of drug therapy taken orally to
restore levels of either estrogen alone or both estrogen and
progestin. Recent studies have shown that HRT can increase a person's
risk of breast cancer, heart disease and stroke. In this
presentation, Robert Frisina, Ph.D., University of Rochester Medical
Center, describes research performed in his laboratory that, among
other things, compared the hearing abilities of older women who had
taken HRT with those who hadn't. They found that the women who had
taken combination HRT had significantly worse hearing than those
taking estrogen HRT alone or those who had never taken HRT. The
results indicate that combination HRT involving progestin appears to
have a negative effect on hearing when compared to estrogen alone.
Understanding the effects of changes in hormone levels on sensory
systems is critical for improving hearing and balance function in
older people. The symposium presentation "Hormone Replacement Therapy
Can Negatively Affect Hearing in Aged Women and Female Mice" takes
place Wednesday, February 20, 2:25 p.m. MST, West 301 A.
Seeing Is Believing — How the Eyes May Help Reveal Hearing Loss
Can an eye exam reveal hearing loss? Researchers at the University of
Oregon believe it can. In previous studies, they have demonstrated
that the pupils of barn owls dilate in a reliable and distinctive way
in response to a sound's loudness, pitch or location, enabling
researchers to assess the detection and discrimination of sounds. In
this study, the researchers evaluated whether this same response —
called the pupillary dilation response (PDR) — may be an effective
tool for measuring hearing loss in people. The researchers had
volunteers listen to sounds of varying loudness and frequency and
compared PDR measurements with traditional measurements in which
subjects indicated detection by voluntarily responding with a yes or
no. They found that the values were similar to one another,
indicating that the PDR approaches the sensitivity of traditional
audiometric tests. The researchers suggest that the PDR is a non-
invasive way of evaluating people's hearing that does not require the
person to speak or otherwise indicate whether or not he or she heard
a sound. This may be useful for patients who are too young or are
physically unable to participate actively in their evaluation. The
poster session "The Pupillary Dilation Response: A Tool for Assessing
Sensory Performance in Humans" takes place Tuesday, February 19, 1:00
p.m. MST (48 hours), West 301 B-D.
Stem Cells Grow in Inner Ears of Novel `Humanized' Mice
Age-related hearing loss is a common problem affecting older adults.
A possible contributing factor is the gradual depletion of
fibrocytes, cells found in the inner ear that play an important role
in the recycling of key electrolytes and that are essential for
normal hearing and balance. Although fibrocytes are able to replenish
themselves after injury, this ability seems to decline with age.
Knowing the source of these fibrocytes and the mechanisms regulating
their replenishment and differentiation may lead to new strategies
for treating age-related hearing loss. Researchers at the Medical
University of South Carolina and the Tokai University School of
Medicine, Tokyo, have shown that fibrocytes in the adult mouse's
inner ear can be derived from hematopoietic stem cells (HSCs), the
blood-forming stem cells that originate from such sources as bone
marrow and umbilical cord blood. In this study, the research team
wanted to learn if fibrocytes in the human inner ear are also derived
from HSCs. They injected human HSCs into mouse models that are
genetically engineered to accept human cells and tissues. After four
months, the percentage of human cells in the mouse's bone marrow
ranged from roughly 26-60 percent. In addition, HSCs were present in
the inner ears of all the recipient mice, including those regions
where fibrocytes are typically located. The poster
session "Engraftment of Human Hematopoietic Stem Cells in the Inner
Ear of a Humanized Mouse Model" takes place Tuesday, February 19,
1:00 p.m. MST (48 hours), West 301 B-D.
Can Cutting Calories Save Your Hearing?
Calorie-restricted diets have been known to fend off many age-related
illnesses and disorders, not to mention death. So could it also
protect against age-related hearing loss? Hearing loss from aging,
also called presbycusis, is one of the most common disorders in older
adults. Not only does it affect hearing, but it is associated with
age-related changes to the brain that can impair a person's ability
to process speech.
Researchers at Southern Illinois University School of Medicine wanted
to find out if cutting calories or feeding animals every other day,
both of which have been found to extend lifespan, could postpone
presbycusis and, if so, whether gender plays a role. Female and male
mice were reared for two years on one of three diets: a diet of 30
percent fewer calories; a diet in which the mice ate every other day;
or a diet in which the mice ate whenever they pleased. After two
years, when both male and female mice began showing signs of
presbycusis, the researchers conducted behavioral tests to assess
hearing. They found that the diets affected the two sexes very
differently. In the males, the calorie-restricted and every-other-
diets appeared to hasten presbycusis. However, in females the
opposite was true: both calorie-restricted and every-other-
resulted in improved hearing when compared to the eat-as-they-
diet. The poster session "Effects of Caloric Restriction and Every
Other Day Feeding on Presbyacusis in a Mouse Model" takes place
Sunday, February 17, 1:00 p.m. MST (48 hours), West 301 B-D.
A Miniaturized Drug-Delivery System for the Inner Ear
When researchers discuss the possibility of drug therapies that can
treat hearing loss and balance disorders, one of the first hurdles is
the development of drugs that are safe and effective in treating
these disorders. Developing drug treatments is a long and costly
process. The second hurdle is getting the drugs to where they need
to go, deep inside the skull to the inner ear. Development of a safe
and efficient route for delivery of drugs to the inner ear represents
a significant technical challenge. Scientists in the Massachusetts
Eye and Ear Infirmary, a part of Harvard Medical School, and the
Draper Laboratory, a research and development laboratory in
Cambridge, Mass., are tackling the second hurdle. Using microfluidic
and microelectromechani
developed a miniaturized pump system that, in animal studies, is able
to safely and effectively deliver drugs to the inner ear for several
hours to several months. Because the device is able to precisely
target the fluid of the inner ear, the researchers suggest that the
device will serve as a useful tool for investigating the molecular
mechanisms associated with inner ear diseases and for testing new
drug treatments. Their goal is to make the micropump and its
electronic components so small that the entire system will one day be
able to be implanted in the mastoid cavity, an opening in the bone
behind a person's ear, allowing for programmable, automated, long-
term delivery of therapeutic compounds to the inner ear. The
symposium presentation "Microfluidic Drug Delivery to the Cochlea"
takes place Monday, February 18, 10:55 a.m. MST, West 101 A-C.
For more information about the Association for Research in
Otolaryngology, visit their Web site at www.aro.org.
NIDCD supports and conducts research and research training on the
normal and disordered processes of hearing, balance, smell, taste,
voice, speech and language and provides health information, based
upon scientific discovery, to the public. For more information about
NIDCD programs, see the Web site at www.nidcd.nih.
The National Institutes of Health (NIH) — The Nation's Medical
Research Agency — includes 27 Institutes and Centers and is a
component of the U.S. Department of Health and Human Services. It is
the primary federal agency for conducting and supporting basic,
clinical and translational medical research, and it investigates the
causes, treatments, and cures for both common and rare diseases. For
more information about NIH and its programs, visit www.nih.gov.
http://www.nih.
«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»«¤»¥«¤»§«¤»¥«¤»§«¤»¥«
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
StemCells subscribers may also be interested in these sites:
Children's Neurobiological Solutions
http://www.CNSfoundation.org/
Cord Blood Registry
http://www.CordBlood.com/at.cgi?a=150123
The CNS Healing Group
http://groups.yahoo.com/group/CNS_Healing
____________________________________________
«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»«¤»¥«¤»§«¤»¥«¤»§«¤»¥«
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Change settings via the Web (Yahoo! ID required)
Change settings via email: Switch delivery to Daily Digest | Switch format to Traditional
Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe
__,_._,___
No comments:
Post a Comment