Potential gene target for treatment of common hearing, vertigo and balance problems
Aires Pharmaceuticals Inc. today announced the signing of an exclusive license agreement with the U.S. National Institutes of Health for the patented use of a nitric oxide prodrug to treat cardiopulmonary conditions. The technology, identified at the NIH’s National Heart, Blood and Lung Institute, shows that nitrite, which is converted by the body into
Full Post: Aires Pharmaceuticals signs license agreement with NIH
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 — the 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. Called benign paroxysmal positional vertigo, the disorder plagues up to 10 percent of people older than 60 and causes 20 percent of patients’ dizziness complaints.
Published Nov. 30 in the advance online edition of Nature , the UCLA findings suggest a potential gene target for the treatment of people suffering from common hearing, vertigo 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,” explained Kent Hill, associate professor of microbiology, immunology and molecular genetics at UCLA’s David Geffen School of Medicine and 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 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 added. “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,” said Hill. “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.”
The study was supported by grants from the National Institutes of Health, the National Science Foundation, the Human Frontier Science Program and the Arnold and Mabel Beckman Foundation.
Hill’s collaborators included co-first coauthor Jessica Colantonio, Adam Langenbacher and Jau-Nian Chen of the David Geffen School of Medicine at UCLA; and co-first author Julien Vermot, David Wu and Scott Fraser of the Beckman Institute California Institute of Technology.
The primary cilium, the solitary, antenna-like structure that studs the outer surfaces of virtually all human cells, orient cells to move in the right direction and at the speed needed to heal wounds, much like a Global Positioning System helps ships navigate to their destinations. “What we are dealing with is a physiological analogy to
Full Post: Primary cilium’s GPS-like cell structure crucial to wound repair
Scientists have shown that tiny crystals found inside bacteria provide a magnetic compass to help them navigate through sediment to find the best food, in research out today. Researchers say their study, published in the Journal of the Royal Society Interface, could provide fresh clues to explain biomagnetism - a phenomenon in which some birds,
Full Post: Tiny magnetic crystals in bacteria are a compass
Episodes of dizziness tend to become less frequent over time in patients with Ménière’s disease, a condition characterized by vertigo, hearing loss and ringing in the ears, according to a report in the November issue of Archives of Otolaryngology-Head & Neck Surgery. A second report finds that a surgical procedure to drain fluid from the
Full Post: Time, surgery appear to reduce episodes of dizziness in patients with Ménière’s
There should be no barriers to providing high-quality speech pathology services, according to University of Queensland PhD graduate Dr Anne Hill. Completed through UQ’s School of Health and Rehabilitation Sciences, Dr Hill’s research found speech and language disorders could be validly and reliably assessed over the internet using a telerehabilitation application. “Having worked clinically with
Full Post: Speech and language disorders can be assessed over the internet
A tiny particle syringe composed of polymer layers and nanoparticles may provide drug delivery that targets diseased cells without harming the rest of the body, according to a team of chemical engineers. This delivery system could be robust and flexible enough to deliver a variety of substances. “People probably fear the effects of some
Full Post: Tiny particle syringe for drug delivery