Researchers have used sound waves to turn stem cells into bone cells, in a tissue engineering advance that could one day help patients regrow bone lost to cancer or degenerative disease. The innovative stem cell treatment from RMIT researchers in Australia offers a smart way forward for overcoming some of the field’s biggest challenges, through the precision power of high-frequency sound waves.

Tissue engineering is an emerging field that aims to rebuild bone and muscle by harnessing the human body’s natural ability to heal itself. A key challenge in regrowing bone is the need for large amounts of bone cells that will thrive and flourish once implanted in the target area. To date, experimental processes to change adult stem cells into bone cells have used complicated and expensive equipment and have struggled with mass production, making widespread clinical application unrealistic. Additionally, the few clinical trials attempting to regrow bone have largely used stem cells extracted from a patient’s bone marrow – a highly painful procedure.

In a new study published in the journal Small, the RMIT research team showed stem cells treated with high-frequency sound waves turned into bone cells quickly and efficiently. Importantly, the treatment was effective on multiple types of cells including fat-derived stem cells, which are far less painful to extract from a patient. Co-lead researcher Dr Amy Gelmi said the new approach was faster and simpler than other methods.

A magnified image showing adult stem cells in the process of turning into bone cells after treatment with high-frequency sound waves. Green colouring shows the presence of collagen, which the cells produce as they become bone cells

“The sound waves cut the treatment time usually required to get stem cells to begin to turn into bone cells by several days,” said Gelmi, a Vice-Chancellor’s Research Fellow at RMIT. “This method also doesn’t require any special ‘bone-inducing’ drugs and it’s very easy to apply to the stem cells. “Our study found this new approach has strong potential to be used for treating the stem cells, before we either coat them onto an implant or inject them directly into the body for tissue engineering.”

The high-frequency sound waves used in the stem cell treatment were generated on a low-cost microchip device developed by RMIT. Co-lead researcher Distinguished Professor Leslie Yeo and his team have spent over a decade researching the interaction of sound waves at frequencies above 10 MHz with different materials. The sound wave-generating device they developed can be used to precisely manipulate cells, fluids or materials. “We can use the sound waves to apply just the right amount of pressure in the right places to the stem cells, to trigger the change process,” Yeo said. “Our device is cheap and simple to use, so could easily be upscaled for treating large numbers of cells simultaneously – vital for effective tissue engineering.”

Source: https://www.rmit.edu.au/

T cells are supposed to defend us from pathogens, but a new mouse study suggests they may also speed aging. Blocking inflammation caused by the cells or boosting their supply of a key metabolic molecule lessened the severity of some aging-related symptoms in rodents, raising the possibility these treatments could benefit older people. The discovery is “a fantastic result directly linking metabolism, inflammation, and aging,” says immunologist Kylie Quinn of RMIT University, Bundoora, in Australia. “They’ve done a really thorough job of making sure it’s the T cells” that are causing the mice to age quickly.

Our T cells let us down as we age, becoming weaker pathogen fighters. This decline helps explain why elderly people are more susceptible to infections and less responsive to vaccines. One reason T cells falter as we get older is that mitochondria, the structures that serve as power plants inside cells, begin to malfunction. But T cells might not just reflect aging. They could also promote it. Older people have chronic inflammation throughout the body, known as inflammaging, and researchers have proposed it spurs aging. T cells may stoke this process because they release inflammation-stimulating molecules.

To test that hypothesis, immunologist María Mittelbrunn of the University Hospital 12 October’s Health Research Institute and colleagues genetically modified mice to lack a protein in the mitochondria of their T cells. This alteration forces the cells to switch to a less efficient metabolic mechanism for obtaining energy.

By the time the rodents were 7 months old, typically the prime of life for a mouse, they already appeared to be in their dotage, the team reports today in Science. Compared with typical mice, the modified rodents were slow and sluggish. They had shrunken, weak muscles and were less resistant to infections. Like many elderly people, they suffered from weakened hearts and shed much of their body fat. T cells from the altered mice poured out molecules that trigger inflammation, the team found, suggesting the cells could be partially responsible for the animals’ physical deterioration. “The immune system plays a role in increasing the velocity of aging,” Mittelbrunn says.

The scientists also tested whether they could slow the aging clock. First they dosed the mice with a drug that blocks tumour necrosis factor alpha (TNF-alpha), one of the inflammation-inducing molecules that T cells unleash; the treatment increased the animals’ grip strength, improved their performance in a maze, and boosted the heart’s pumping power.

Mittelbrunn and colleagues also gave the animals a compound that raises levels of nicotinamide adenine dinucleotide (NAD), a molecule that’s vital for metabolic reactions that enable cells to extract energy from food. NAD’s cellular concentrations typically decline with age, and the researchers found that ramping it up in the mice made them more active and strengthened their hearts.

Source: https://researchbank.rmit.edu.au/
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https://www.sciencemag.org/

Researchers have developed an ultra-thin and ultra-flexible electronic material that could be printed and rolled out like newspaper, for the touchscreens of the future. The touch-responsive technology is 100 times thinner than existing touchscreen materials and so pliable it can be rolled up like a tube.

To create the new conductive sheet, an RMIT University-led team used a thin film common in mobile phone touchscreens and shrunk it from 3D to 2D, using liquid metal chemistry. The nano-thin sheets are readily compatible with existing electronic technologies and because of their incredible flexibility, could potentially be manufactured through roll-to-roll (R2R) processing just like a newspaper. Lead researcher Dr Torben Daeneke said most mobile phone touchscreens were made of a transparent material, indium-tin oxide, that was very conductive but also very brittle.

“We’ve taken an old material and transformed it from the inside to create a new version that’s supremely thin and flexible,” said Daeneke, an Australian Research Council DECRA Fellow at RMIT. “You can bend it, you can twist it, and you could make it far more cheaply and efficiently than the slow and expensive way that we currently manufacture touchscreens. “Turning it two-dimensional also makes it more transparent, so it lets through more light. “This means a mobile phone with a touchscreen made of our material would use less power, extending the battery life by roughly 10%.”

The research, with collaborators from UNSW, Monash University and the ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), is published in the journal Nature Electronics.

Source: https://www.rmit.edu.au/

Researchers have used sound waves to precisely manipulate atoms and molecules, accelerating the sustainable production of breakthrough smart materials.  Metal Organic Frameworks, or MOFs, are incredibly versatile and super porous nanomaterials that can be used to store, separate, release or protect almost anything. Predicted to be the defining material of the 21st century, MOFs are ideal for sensing and trapping substances at minute concentrations, to purify water or air, and can also hold large amounts of energy, for making better batteries and energy storage devices. Scientists have designed more than 88,000 precisely-customised MOFs – with applications ranging from agriculture to pharmaceuticals – but the traditional process for creating them is environmentally unsustainable and can take several hours or even days. 

Now researchers from RMIT in Australia have demonstrated a clean, green technique that can produce a customised MOF in minutes. Dr Heba Ahmed, lead author of the study published in Nature Communications, said the efficient and scaleable method harnessed the precision power of high-frequency sound waves.

Dr Heba Ahmed holding a MOF created with high-frequency sound waves

“MOFs have boundless potential, but we need cleaner and faster synthesis techniques to take full advantage of all their possible benefits,” Ahmed, a postdoctoral researcher in RMIT’s Micro/Nanophysics Research Laboratory, said. “Our acoustically-driven approach avoids the environmental harms of traditional methods and produces ready-to-use MOFs quickly and sustainably. “The technique not only eliminates one of the most time-consuming steps in making MOFs, it leaves no trace and can be easily scaled up for efficient mass production.”

Metal-organic frameworks are crystalline powders full of tiny, molecular-sized holes. They have a unique structure – metals joined to each other by organic linkers – and are so porous that if you took a gram of a MOF and spread out its internal surface area, you would cover an area larger than a football pitch. Some have predicted MOFs could be as important to the 21st  century as plastics were to the 20th.

During the standard production process, solvents and other contaminants become trapped in the MOF’s holes. To flush them out, scientists use a combination of vacuum and high temperatures or harmful chemical solvents in a process called “activation”. In their novel technique, RMIT researchers used a microchip to produce high-frequency sound waves. Co-author and acoustic expert Dr Amgad Rezk said these sound waves, which are not audible to humans, can be used for precision micro- and nano-manufacturing.

“At the nano-scale, sound waves are powerful tools for the meticulous ordering and manoeuvring of atoms and molecules,” Rezk said.

Source: https://www.rmit.edu.au/

From moods to memory, the brain in our guts has a big impact on the brain in our heads. Pioneering neuroscientist Associate Professor Elisa Hill-Yardin from RMIT in Australia has spent years delving deep into the gut-brain connection, an emerging field in health research. Here she shares the five critical things we should know about our “gut brain”.

The gut has similar types of neurons to the brain. The gut brain is a big nervous system, about the same size as the spinal cord, which controls the contractions of the gut and its secretions. There are very rare gene mutations that affect brain connectivity and we’ve learned that the vast majority of those gene mutations are also found in the gut. If those mutations change the wiring in the brain, they’re also likely to change the wiring and the action of the gut brain – the enteric nervous system. To date, we’ve only ever examined the effect of those mutations in the brain. Now we’re starting to look at them in our second brain, the gut.

We now know that microbes in the gut do change our mood and behaviour, and microbes even change brain activity. There’s a great study that looked at women, doing MRI brain scans and showing that if they ate yoghurt for a certain number of days their resting brain activity was different – which is amazing! But we also know from animal studies that microbes have an impact on mental health. You can breed mice that are germ free and we know that those mice show differences in their anxiety behaviours – in other words, they’re less anxious without the microbes. So you could say we’re being controlled by the microbes in our gut. They’re much more important to our feelings than we ever thought.

What’s come out in research in recent years, though it’s been known for a long time in the autism community, is that the majority of children with autism have serious gut problems. Now we don’t know the cause of autism but we do know that there are hundreds and hundreds of rare gene mutations that alter brain connectivity. And we now know that some of those mutated genes are also found in the gut. We’re also learning that diseases that affect cognition and memory, like dementia, may also have a gut component. Researchers are starting to look at traditional brain diseases like Alzheimer’s, Parkinson’s, Multiple Sclerosis, and finding difference in the microbes in the gut. So they’re starting to think about how we can make changes in our microbes to make changes to our brain health.

The Gut-Brain Axis team that I lead at RMIT is focused on understanding how the enteric nervous system is altered in neurological disorders such as autism. This includes researching how the gut nervous system interacts with microbes in the intestine and changes in inflammatory pathways. We’re trying to identify the basic mechanisms, examining the connections between the gastrointestinal tract and changes in mood and behaviour, including the impact of genetics on microbiota in the gut. The ultimate the aim is to find novel therapies that can improve daily life for people with autism, but our work also has broader application for other neurological disorders, such Parkinson’s disease.

Many of the great enteric physiologist pioneers are in Australia and they were the first to describe different types of neurons based on their activity and neurochemical content. This work has been done on animal models, due to the possibilities of emulating human genetic diseases in these models. So, a lot of basic anatomy and physiology has been studied. But what we need now is to move the field towards using the latest sophisticated techniques and capitalising on the recent interest in the gut-brain axis, which of course involves understanding how the gastrointestinal tract works in concert with the trillions of microbes that live inside it.

Professor Elisa Hill-Yardin has presented her work to the US Air Force Office of Scientific Research

Source: https://www.rmit.edu.au/

In Australia, UNSW and RMIT researchers have discovered a revolutionary and cheap way to make filters that can turn water contaminated with heavy metals into safe drinking water in a matter of minutes. Recent UNSW SHARP hire Professor Kourosh Kalantar-zadeh and his former colleagues at RMIT showed that nano-filters made of aluminium oxide could be cheaply produced using virtually no energy from a fixed amount of liquid metal gallium.

In a paper published in Advanced Functional Materials, lead author Dr Ali Zavabeti (RMIT) and Professor Kalantar-zadeh explained that when a chunk of aluminium is added to the core of liquid gallium at room temperature, layers of aluminium oxide are quickly produced at the surface of the gallium. The authors discovered that these aluminium oxide nano-sheets were highly porous and went on to prove they were suitable for filtering both heavy metal ions and oil contamination at unprecedented, ultra-fast rates. Professor Kalantar-zadeh, who was recently awarded an ARC Australian Laureate Fellowship soon after joining UNSW‘s School of Chemical Engineering, said that low cost and portable filters produced by this new liquid metal based manufacturing process could be used by people without access to clean drinking water to remove substances like lead and other toxic metals in a matter of minutes.

“Because it’s super porous, water passes through very rapidly,” Professor Kalantar-zadeh said. “Lead and other heavy metals have a very high affinity to aluminium oxide. As the water passes through billions of layers, each one of these lead ions get attracted to one of these aluminium oxide sheets. “But at the same time, it’s very safe because with repeated use, the water flow cannot detach the heavy metal ions from the aluminium oxide.”

Professor Kalantar-zadeh believes the technology could be put to good use in Africa and Asia in places where heavy metal ions in the water are at levels well beyond safe human consumption. It is estimated that 790 million people, or one in 10 of the Earth’s population, do not have access to clean water. “If you’ve got bad quality water, you just take a gadget with one of these filters with you,” he said. “You pour the contaminated water in the top of a flask with the aluminium oxide filter. Wait two minutes and the water that passes through the filter is now very clean water, completely drinkable. “And the good thing is, this filter is cheap.”

There are portable filtration products available that do remove heavy metals from water, but they are comparatively expensive, often costing more than $100. By contrast, aluminium oxide filters produced from liquid gallium could be produced for as little as 10 cents, making them attractive to prospective manufacturers.

Source: http://newsroom.unsw.edu.au/