First new sound wave class in half a century to revolutionise stem cell therapy

A new class of sound wave has been developed for the first time in 50 years that looks set to revolutionise the use of stem cells in medical treatments.

Created by acoustics experts from RMIT University in Melbourne, Australia, the sound waves – known as “surface reflected bulk waves” – are gentle enough to manipulate stem cells without causing damage, something that has not previously been possible with sound waves.

The researchers have already used the technology to significantly improve the efficiency of an advanced nebuliser device developed at RMIT, which delivers medicine directly to the lungs.

“We have used the new sound waves to slash the time required for inhaling vaccines through the nebuliser device, from 30 minutes to as little as 30 seconds,” said study co-author Dr Amgad Rezk, from the Micro/Nano Research Laboratory at RMIT.

“But our work also opens up the possibility of using stem cells more efficiently for treating lung disease, enabling us to nebulise stem cells straight into a specific site within the lung to repair damaged tissue. This is a real game changer for stem cell treatment in the lungs.”

Amgad-Rezk

Dr Amgad Rezk, who co-authored the study with PhD researcher James Tan.

Surface reflected bulk waves are known as such due to their combination of bulk sound waves and surface sound waves.

Bulk sound waves cause an entire material to vibrate as one, an effect that the researchers liken to holding a carpet at one end and shaking it.

By contrast, surface sound waves only cause the surface of a material to vibrate, with the researchers comparing the effect to waves in an ocean.

By combining the two, the researchers have created a sound wave class that is far more powerful than its component wave types.

“The combination of surface and bulk wave means they work in harmony and produce a much more powerful wave,” said Rezk.

“As a result, instead of administering or nebulising medicine at around 0.2ml per minute, we did up to 5ml per minute. That’s a huge difference.”

Professor Leslie Yeo, also of RMIT, demonstrates the Respite nebuliser, which this research has improved. Images courtesy of RMIT.

Professor Leslie Yeo, also of RMIT, demonstrates the Respite nebuliser, which this research has improved. Inline images courtesy of RMIT.

The researchers have created a device to utilise surface reflected bulk waves in medical devices with the rather epic name HYDRA.

This passes electricity through a piezoelectric chip, converting it into mechanical vibration, or sound waves, that can break liquid into a spray so it can be inhaled.

“It’s basically ‘yelling’ at the liquid so it vibrates, breaking it down into vapour,” explained Rezk.

HYDRA has been used to improve RMIT’s advanced nebula, known as Respite, which can be used to deliver a wide range of drugs into the body without the need for pills or injections.

For sufferers of asthma and cystic fibrosis, the device can deliver highly precise drug doses, but it can also be used to provide diabetes patients with insulin, and give infants vaccines without an injection.

The details of the research have been published today in the journal Advanced Materials.

Researchers discover remains of “Triassic Jaws” who dominated the seas after Earth’s most severe mass extinction event

Researchers have discovered the fossil remains of an unknown large predatory fish called Birgeria: an approximately 1.8-meter-long primitive bony fish with long jaws and sharp teeth that swallowed its prey whole.

Swiss and US researchers led by the Paleontological Institute and Museum of the University of Zurich say the Birgeria dominated the sea that once covered present-day Nevada one million years after the mass extinction.

Its period of dominance began following “the most catastrophic mass extinction on Earth”, which took place about 252 million years ago – at the boundary between the Permian and Triassic geological periods.

Image courtesy of UZH. Featured image courtesy of Nadine Bösch

Up to 90% of the marine species of that time were annihilated, and before the discovery of the Birgeria, palaeontologists had assumed that the first predators at the top of the food chain did not appear until the Middle Triassic epoch about 247 to 235 million years ago.

“The surprising find from Elko County in northeastern Nevada is one of the most completely preserved vertebrate remains from this time period ever discovered in the United States,” emphasises Carlo Romano, lead author of the study.

Although, species of Birgeria existed worldwide. The most recent discovery belongs to a previously unknown species called Birgeria Americana, and is the earliest example of a large-sized Birgeria species, about one and a half times longer than geologically older relatives.

The researchers say the discovery of Birgeria is proof that food chains recovered quicker than previously thought from Earth’s most devastating mass extinction event.

According to earlier studies, marine food chains were shortened after the mass extinction event and recovered only slowly and stepwise.

However, finds such as the newly discovered Birgeria species and the fossils of other vertebrates now show that so-called apex predators (animals at the very top of the food chain) already lived early after the mass extinction.

“The vertebrates from Nevada show that previous interpretations of past biotic crises and associated global changes were too simplistic,” said Romano.

Revolutionary DNA sunscreen gives better protection the longer its worn

Researchers have developed a ground-breaking sunscreen made of DNA that offers significant improvements over conventional versions.

Unlike current sunscreens, which need to be reapplied regularly to remain effective, the DNA sunscreen improves over time, offering greater protection the longer it is exposed to the sun.

In addition, it also keeps the skin hydrated, meaning it could also be beneficial as a treatment for wounds in extreme or adverse environments.

Developed by researchers from Binghamton University, State University of New York, the innovative sunscreen could prove essential as temperatures climb and many are increasingly at risk of conditions caused by excessive UV exposure, such as skin cancer.

“Ultraviolet (UV) light can actually damage DNA, and that’s not good for the skin,” said Guy German, assistant professor of biomedical engineering at Binghamton University.

“We thought, let’s flip it. What happens instead if we actually used DNA as a sacrificial layer? So instead of damaging DNA within the skin, we damage a layer on top of the skin.”

The DNA sunscreen has the potential to become a standard, significantly improving the safety of spending time in the sun

The research, which is published today in the journal Scientific Reports, involved the development of thin crystalline DNA films.

These films are transparent in appearance, but able to absorb UV light; when the researchers exposed the film to UV light, they found that its absorption rate improved, meaning the more UV is was exposed to, the more it absorbed.

“If you translate that, it means to me that if you use this as a topical cream or sunscreen, the longer that you stay out on the beach, the better it gets at being a sunscreen,” said German.

The film will no doubt attract the attention of sunscreen manufacturers, who will likely be keen to commercialise such a promising product. However, the researchers have not said if there is any interest as yet, and if there is any clear timeline to it becoming a commercial product.

 

The film’s properties are not just limited to sun protection, however. The DNA film can also store water at a far greater rate than conventional skin, limiting water evaporation and increasing the skin’s hydration.

As a result, the film is also being explored as a wound covering, as it would allow the wound to be protected from the sun, keep it moist – an important factor for improved healing – and allow the wound to be monitored without needing to remove the dressing.

“Not only do we think this might have applications for sunscreen and moisturizers directly, but if it’s optically transparent and prevents tissue damage from the sun and it’s good at keeping the skin hydrated, we think this might be potentially exploitable as a wound covering for extreme environments,” said German.