Categories
Asia Noise News

Ultrasound Selectively Damages Cancer Cells When Tuned to Correct Frequencies

Doctors have used focused ultrasound to destroy tumors in the body without invasive surgery for some time. However, the therapeutic ultrasound used in clinics today indiscriminately damages cancer and healthy cells alike.

Most forms of ultrasound-based therapies either use high-intensity beams to heat and destroy cells or special contrast agents that are injected prior to ultrasound, which can shatter nearby cells. Heat can harm healthy cells as well as cancer cells, and contrast agents only work for a minority of tumors.

Researchers at the California Institute of Technology and City of Hope Beckman Research Institute have developed a low-intensity ultrasound approach that exploits the unique physical and structural properties of tumor cells to target them and provide a more selective, safer option. By scaling down the intensity and carefully tuning the frequency to match the target cells, the group was able to break apart several types of cancer cells without harming healthy blood cells.Their findings, reported in Applied Physics Letters, from AIP Publishing, are a new step in the emerging field called oncotripsy, the singling out and killing of cancer cells based on their physical properties.

Targeted pulsed ultrasound takes advantage of the unique mechanical properties of cancer cells to destroy them while sparing healthy cells.

“This project shows that ultrasound can be used to target cancer cells based on their mechanical properties,” said David Mittelstein, lead author on the paper. “This is an exciting proof of concept for a new kind of cancer therapy that doesn’t require the cancer to have unique molecular markers or to be located separately from healthy cells to be targeted.”

A solid mechanics lab at Caltech first developed the theory of oncotripsy, based on the idea that cells are vulnerable to ultrasound at specific frequencies — like how a trained singer can shatter a wine glass by singing a specific note.

The Caltech team found at certain frequencies, low-intensity ultrasound caused the cellular skeleton of cancer cells to break down, while nearby healthy cells were unscathed.

“Just by tuning the frequency of stimulation, we saw a dramatic difference in how cancer and healthy cells responded,” Mittelstein said. “There are many questions left to investigate about the precise mechanism, but our findings are very encouraging.”The researchers hope their work will inspire others to explore oncotripsy as a treatment that could one day be used alongside chemotherapy, immunotherapy, radiation and surgery. They plan to gain a better understanding of what specifically occurs in a cell impacted by this form of ultrasound.

Written by:

Phawin Phanudom (Gun)
Acoustical Engineer

Geonoise (Thailand) Co., Ltd.
Tel: +6621214399
Mobile: +66891089797
Web: https://www.geonoise.com
Email: phawin@geonoise.asia

Credit: Publishing AIP

Categories
Asia Noise News

Dogs Can Experience Hearing Loss

Just like humans, dogs are sometimes born with impaired hearing or experience hearing loss as a result of disease, inflammation, aging or exposure to noise. Dog owners and K-9 handlers ought to keep this in mind when adopting or caring for dogs, and when bringing them into noisy environments, says Dr. Kari Foss, a veterinary neurologist and professor of veterinary clinical medicine at the University of Illinois at Urbana-Champaign.

In a new report in the journal Topics in Companion Animal Medicine, Foss and her colleagues describe cases of hearing loss in three working dogs: a gundog, a sniffer dog and a police dog. One of the three had permanent hearing loss, one responded to treatment and the third did not return to the facility where it was originally diagnosed for follow-up care.

The case studies demonstrate that those who work with police or hunting dogs “should be aware of a dog’s proximity to gunfire and potentially consider hearing protection,” Foss said. Several types of hearing protection for dogs are available commercially.

Just as in humans, loud noises can harm the delicate structures of a dog’s middle and inner ear.

“Most commonly, noise-induced hearing loss results from damage to the hair cells in the cochlea that vibrate in response to sound waves,” Foss said. “However, extreme noise may also damage the eardrum and the small bones within the inner ear, called the ossicles.”

Pet owners or dog handlers tend to notice when an animal stops responding to sounds or commands. However, it is easy to miss the signs, especially in dogs with one or more canine companions, Foss said.

“In puppies with congenital deafness, signs may not be noticed until the puppy is removed from the litter,” she said.

Signs of hearing loss in dogs include failing to respond when called, sleeping through sounds that normally would rouse them, startling at loud noises that previously didn’t bother them, barking excessively or making unusual vocal sounds, Foss said. Dogs with deafness in one ear might respond to commands but could have difficulty locating the source of a sound.

If pet owners think their pet is experiencing hearing loss, they should have the animal assessed by a veterinarian, Foss said. Hearing loss that stems from ear infections, inflammation or polyps in the middle ear can be treated and, in many cases, resolved.

Hearing-impaired or deaf dogs may miss clues about potential threats in their surroundings, Foss said.

“They are vulnerable to undetected dangers such as motor vehicles or predators and therefore should be monitored when outside,” she said.

If the hearing loss is permanent, dog owners can find ways to adapt, Foss said.

“Owners can use eye contact, facial expressions and hand signals to communicate with their pets,” she said. “Treats, toy rewards and affection will keep dogs interested in their training.” Blinking lights can be used to signal a pet to come inside.

Hearing loss does not appear to affect dogs’ quality of life, Foss said.”A dog with congenital hearing loss grows up completely unaware that they are any different from other dogs,” she said. “Dogs that lose their hearing later in life may be more acutely aware of their hearing loss, but they adapt quite well. A dog’s life would be significantly more affected by the loss of smell than by a loss of hearing.”

Written by:

Pitupong Sarapho (Pond)
Acoustical Engineer

Geonoise (Thailand) Co., Ltd.
Tel: +6621214399
Mobile: +66868961299
Email: pond@geonoise.asia

Credit: Diana Yates, University of Illinois at Urbana-Champaign