 |
|
Can you hear me now? How the inner ear's sensors are made
December 02, 2008UCLA study offers new clues for treatment of vertigo, hearing problems
A UCLA study shows for the first time how microscopic crystals form sound and gravity sensors inside the inner ear. Located at the ends of cilia - tiny cellular hairs in the ear that move and transmit signals - these crystals play an important role in detecting sound, maintaining balance and regulating movement.
Dislodged ear crystals are to blame for the most common form of vertigo. Known as benign paroxysmal positional vertigo, the disorder plagues up to 10 percent of people older than 60 and causes 20 percent of patients' dizziness complaints.
The researchers' findings, published Nov. 30 in the advance online edition of the journal Nature, suggest a potential gene target for the treatment of people suffering from common hearing and balance problems related to cilia disorders.
"People have known for a long time about the importance of cilia for propelling sperm up the uterus and moving mucus out of the lungs," said Kent Hill, associate professor of microbiology, immunology and molecular genetics at the David Geffen School of Medicine at UCLA and the UCLA College of Letters and Science. "Our study illustrates that cilia perform many additional jobs that are essential to how our bodies develop and work."
Hill's team employed high-speed, high-definition video imaging to watch cilia moving in real-time inside the developing ears of embryonic zebrafish. These small, bony fish undergo stages of development similar to humans and other vertebrates, making them useful models for research.
The researchers labeled cilia in the fish with fluorescent probes and used video microscopy to visualize the cilia and other inner ear structures. In the control group of fish, long cilia beat like tiny oars, causing tiny particles to circle in a vortex around them. The tornado of whirling particles accumulated at the proper location to form the inner ear's crystalline sensors.
"We next blocked expression of a gene that controls dynein - a tiny molecular motor that drives cilia movement," said Hill. "When we examined the embryos, we saw that cilia movement came to a halt. As a result, the particles did not assemble in the correct site. So not only did ear crystals form in the wrong place, but they were misshapen and abnormally sized."
"While it's been suggested that cilia movement contributes to the formation of ear crystals, this idea had never been tested before," he said. "Our findings show that cilia in the ear do move and demonstrate that cilia movement is needed for ear crystals to assemble in the right place."
According to Hill, the findings offer promise for the treatment of patients with hearing disorders and people with ciliopathies, disorders marked by poor cilia function. These conditions include sperm-related infertility, polycystic kidney disease, lung and respiratory disorders, swelling of the brain, and reversal of the internal organs' sites from one side of the body to the other.
"The idea that physical movement can influence vertebrate development is very provocative," Hill said. "Scientists typically look at whether a particular gene is switched on or off, or if a particular protein is activated that determines if a tissue develops normally. In this case, microscopic currents in the fluid surrounding developing tissue are affecting its development. We need to understand more details of this process and determine how common it is during development."
University of California - Los Angeles
The researchers' findings, published Nov. 30 in the advance online edition of the journal Nature, suggest a potential gene target for the treatment of people suffering from common hearing and balance problems related to cilia disorders.
"People have known for a long time about the importance of cilia for propelling sperm up the uterus and moving mucus out of the lungs," said Kent Hill, associate professor of microbiology, immunology and molecular genetics at the David Geffen School of Medicine at UCLA and the UCLA College of Letters and Science. "Our study illustrates that cilia perform many additional jobs that are essential to how our bodies develop and work."
Hill's team employed high-speed, high-definition video imaging to watch cilia moving in real-time inside the developing ears of embryonic zebrafish. These small, bony fish undergo stages of development similar to humans and other vertebrates, making them useful models for research.
The researchers labeled cilia in the fish with fluorescent probes and used video microscopy to visualize the cilia and other inner ear structures. In the control group of fish, long cilia beat like tiny oars, causing tiny particles to circle in a vortex around them. The tornado of whirling particles accumulated at the proper location to form the inner ear's crystalline sensors.
"We next blocked expression of a gene that controls dynein - a tiny molecular motor that drives cilia movement," said Hill. "When we examined the embryos, we saw that cilia movement came to a halt. As a result, the particles did not assemble in the correct site. So not only did ear crystals form in the wrong place, but they were misshapen and abnormally sized."
"While it's been suggested that cilia movement contributes to the formation of ear crystals, this idea had never been tested before," he said. "Our findings show that cilia in the ear do move and demonstrate that cilia movement is needed for ear crystals to assemble in the right place."
According to Hill, the findings offer promise for the treatment of patients with hearing disorders and people with ciliopathies, disorders marked by poor cilia function. These conditions include sperm-related infertility, polycystic kidney disease, lung and respiratory disorders, swelling of the brain, and reversal of the internal organs' sites from one side of the body to the other.
"The idea that physical movement can influence vertebrate development is very provocative," Hill said. "Scientists typically look at whether a particular gene is switched on or off, or if a particular protein is activated that determines if a tissue develops normally. In this case, microscopic currents in the fluid surrounding developing tissue are affecting its development. We need to understand more details of this process and determine how common it is during development."
University of California - Los Angeles
Science News and Science Current Events Tag Cloud
This tag cloud is a visual representation of term frequencies of random science news topics with common terms grouped together and emphasized by their display size.
Thyroid Cancer Genome sequence Water Molecules Blood-brain Barrier Bisphenol A Self-esteem Mosquito Cistic Fibrosis Atmospheric Carbon Dioxide Osteoarthritis Marriage Behavioral Problems Heart Attack Radiotherapy Placebo Carbon Emissions Alcohol Consumption Butterflies Quantum Computing Caesarean Black Hole Bipolar Amyloid-beta Fingerprints Ozone
See More: Science News Tags
Inner Ear Current Events and Inner Ear News RSSDrawing inspiration from nature to build a better radio
MIT engineers have built a fast, ultra-broadband, low-power radio chip, modeled on the human inner ear, that could enable wireless devices capable of receiving cell phone, Internet, radio and television signals.
Inner ear balance disorders common, associated with falls among older Americans
An estimated 35 percent of U.S. adults age 40 and older have vestibular dysfunction (inner ear balance disorders), and those who do may have a higher risk of falling.
Scripps research scientists discover molecular defect involved in hearing loss
Scientists from The Scripps Research Institute have elucidated the action of a protein, harmonin, which is involved in the mechanics of hearing.
Stanford researcher's discovery of ion channel turns ear on its head
Scientists thought they had a good model to explain how the inner ear translates vibrations in the air into sounds heard by the brain. Now, based on new research from the Stanford University School of Medicine, it looks like parts of the model are wrong.
Researchers find lack of key molecule leads to deafness
Researchers have identified tiny molecules that may lead to big breakthroughs in the treatment of hearing loss and deafness.
Scaling the Wall of Deafness
Despite modern medicine, one in 1,000 American babies are born deaf. The numbers increase markedly with age, with more than 50% of seniors in the United States experiencing some form of hearing loss.
New insights into progressive hearing loss
In parallel studies in human and mouse, two groups of researchers have come to the same conclusion: that a new kind of gene is associated with progressive hearing loss.
Search for blood pressure secrets reveals a surprising new syndrome
Yale researchers investigating the genetic causes of blood pressure variation have identified a previously undescribed syndrome associated with seizures, a lack of coordination, developmental delay and hearing loss.
Study offers clues to beating hearing loss
Researchers at the University of Leeds have made a significant step forward in understanding the causes of some forms of deafness.
New iPod listening study shows surprising behavior of teens
A new study involving iPods and teenagers by the University of Colorado at Boulder and Children's Hospital Boston indicates teenagers who receive pressure from their peers or others to turn down the volume of their iPods instead turn them up higher.
More Inner Ear Current Events and Inner Ear News Articles
 |
Inner Ear Balance and Dizziness Disorders by P.J. Haybach (Author) Inner Ear Balance and Dizziness Disorders is for anyone who wants to know more about vestibular disorders. These disorders, their effect and treatment are all explained in an easy to understand style. |
 |
Inner Ear Balance and Dizziness Disorders by Haybach Inner Ear Balance and Dizziness Disorders is for anyone who wants to know more about vestibular disorders. These disorders, their effect and treatment are all explained in an easy to understand style. |
 |
Woodees IESW100B Inner-ear Stereo Earphone with Microphone by Woodies Wood Sounds Richer. The finest musical instruments have always been made from wood. Like a finely-tuned piano or the best acoustic guitars, Woodees from iConnects deliver pure and natural listening pleasure. Wood sounds amazing¿nothing beats its deep bass, rich range of sound and inherent low resonance. And for your money, nothing beats Woodees. These natural wood earphones bring out a dense, polished listening experience from your mp3 player. And at about half the price of comparable high-end ear buds, you¿re getting the best sound at the best price. Woodees from iConnects.Give your ears a pair today. Compatible with iPhone & 2G 3G Smartphones. |
 |
Animal Parade Inner Ear Support - Cherry - 90 - Chewable by Nature's Plus Source of Life® Animal Parade® Children's Chewable Inner Ear Support Animal Parade® Childrens Chewable Inner Ear Support formula is the most exciting advance in probiotics since the discovery of Lactobacillus acidophilus! This irresistibly delicious natural cherry flavored chewable brings the power of K12 probiotics to the inner ear and throat; right where children need it most! With Animal Parade Childrens Chewable Inner Ear Support supplement, parents can enlist the help of billions of live probiotic cells to maintain a balanced ecology in the inner ear, mouth and throat. Reinforced with the cooling, calming, soothing activity of chamomile and mullein extracts, Animal Parade Childrens Chewable Inner Ear Support supplement offers complete probiotic... |
 |
Inner-ear Headset with In-line Microphone by Sony Designed for use with your mobile phone, the DR-E111 headset is perfect when you're on the go or in the office. This headset features a lightweight, basic inner ear style that fits comfortably. The DR-E111 works with most cellular phones with a standard 2.5mm jack except the Nokia 1200/3000/8000 series phones. |
 |
Native Remedies Vertifree To Temporarily Support Inner Ear Balance (125 Tablets), 0.2 Units by Native Remedies |
 |
Inner Ear by Third Hand |
 |
3" button / pin printed with Inner Ear by Shopzeus Customized 3" button / pin. |
 |
Inner Ear Onesie by Shop Zeus |
 |
Sony Inner-Ear Headset with In-Line Microphone (Model# DR-E111/PINK) by Sony Features: * Works with most mobile phones with standard 2.5mm jack except the Nokia 1200/3000/8000 series phones * 4.9ft (1.2m) cord * Inner ear type * Lightweight Design * Hands-free headset * Mono, in-line microphone |
| © 2009 BrightSurf.com |