Tag Archives: Australian medical news

bacterial biofilms

Molecular warfare

Featured image above: Cyrille Boyer of UNSW’s School of Chemical Engineering. Credit: Quentin Jones

We often picture disease-causing bacteria as an invading army of individual cells. But in fact, these pathogens find strength in numbers, glomming onto each other and coating the surfaces around them in near-indestructible protective sheets called biofilms.  

These biofilms pose an enormous problem in medicine. They can form directly on lungs, wounds or other living tissue, and can contaminate medical devices such as catheters, prosthetic joints and other implants. Food production, water treatment, and other industrial facilities can also fall victim to their powers. Many types of biofilms resist antibiotics, and the bacteria they’re built from churn out toxins that make their human hosts sick. Yet, no good way exists to destroy them. 

Cyrille Boyer, a polymer chemist and Co-Director of the Australian Centre for Nanomedicine at UNSW in collaboration with Dr Nicolas Barraux, believes that a nanomaterial he designed – a polymer-coated iron oxide particle that heats up when a magnetic field is applied – can provide a solution.

In December 2015, he and his colleagues reported in Nature’s open access journal Scientific Reports that using these nanoparticles to raise the temperature of a biofilm by just a few degrees caused it to break apart.

bacterial biofilm

bacterial biofilm
Biofilm of staphylococcus aureus (or ‘golden staph’) on a catheter; bloodstream infections with this bacteria kill 20 to 35% of patients within a year.

Solo-swimming bacteria are much more susceptible to antibiotics, Boyer explains, so the researchers could then send in another type of particle to deliver medicine that kills off the bugs. They are now planning on testing the particles in live mice and discussing a potential partnership with a company interested in taking the method into clinical development.  

Polymer chemist Eva Harth from Vanderbilt University in Tennessee, describes it as an out-of-the-box strategy to treat a long-intractable problem.

This paper shows that a polymer construct can be much more effective than a traditional drug,” she says. 

“There’s an enormous need for new technologies” for breaking up biofilms, says Rodney Dolan, Director of the Biofilms Laboratory at the US Centers for Disease Control and Prevention. “It’s a very creative, very interesting approach, particularly combining particles with magnetic fields to localise and control the effect.” 

Smart, easy, elegant solution

Boyer is a master of materials, and his specialty is controlling the effects of the nanoparticles and polymers he creates.

“In my team, we are looking at how to make smarter nanoparticles, where the nanoparticle acts in response to an external signal,” he says.

In 2015, Boyer was awarded the Australian Prime Minister’s Prizes for Science Malcolm McIntosh Prize for Physical Scientist of the Year for his work using light to catalyse the assembly of polymers with distinct properties. Although the biofilm-busting technique doesn’t employ light, it’s right in line with Boyer’s vision of building ‘smart’ particles whose behaviour can be controlled for therapeutic purposes.  

Boyer created his iron oxide particles in response to a discovery made by microbiologist Nicolas Barraud at the Institut Pasteur in Paris, France. The two met by chance, when Barraud, then based at UNSW, was attending a conference out of town. He popped
in on a talk Boyer was giving about polymers that release nitric oxide.
“It was a serendipitous meeting,” he says. “We realised we were working at the same university, a few buildings across.”  

Barraud was studying the basic properties of biofilm formation and dispersal, and had recently discovered that nitric oxide could break up biofilms. Back in Sydney, he asked Boyer if he could try the polymers described in the talk. Boyer was happy to comply, and the approach worked relatively well, according to both researchers.

They published a couple of papers, filed a patent, and are still pursuing the project — but the drawback was that nitric oxide is a gas, which makes it difficult to spatially and temporally control its release.

Barraud had also discovered that giving biofilms a tiny temperature boost made the bacteria move and shake, ultimately disbanding them, but he couldn’t work out how to apply the discovery. Then one day, over a beer, Boyer mentioned that he could create particles that induce local heating. “I’ve worked with chemists before,” Barraud says, “and usually as soon as you get into the lab you run into problems. But with Cyrille’s polymer, it was very straightforward,” he says.  

That’s because in this project and others, Boyer focuses on identifying simple, well-worked-out polymerisation methods that can be used in specific applications. “Very precise materials that are easy to make – that’s the key,” says Harth. “It’s smart, easy, and elegant – that’s what he’s after.”

– Alla Katsnelson

For more stories at the forefront of engineering research, check out Ingenuity magazine.

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wound healing

Wound healing clinic to change lives

A dedicated wound healing clinic – the first in Australia – opens on Tuesday, 7 March. It draws together a pool of specialist wound healing talent that includes a vascular surgeon, nurse practitioners, an advanced podiatrist and specialist wound nurses in one spot to treat and assess chronic wounds.

The clinic, Wound Innovations, is in Spring Hill, Brisbane and accessible to all Australians via the Spring Hill teleclinic, which connects patients and health professionals with a specialist from Wound Innovations through videoconferencing facilities. Wound Innovations also offers education for health professionals and will be a site for clinical trials and other research projects. 

Living with a serious wound is incredibly debilitating. “Wounds are painful and can exude a fluid. People with a wound can suffer from a lack of mobility and this leads to less social interaction, and isolation,” explains Dr Ian Griffiths, CEO of the Wound Management Innovation Co-operative Research Centre (CRC), which runs Wound Innovations.

“Often people are afraid to go out because of the smell from their wounds. It can take you down a very dark path.”

Dr Griffiths says there is medical research linking wounds with depression as well as dementia.

The teleclinic takes high resolution photos of each patient’s wounds to monitor progress and the patient provides feedback, while wound healing experts make recommendations for future care. Appointments may attract a Medicare rebate.

Griffiths expects the wound healing clinic and teleclinic to be a life changer for patients and plans to open other wound healing clinics with specialised teams in capital cities around Australia.

He also expects dramatic savings to the Australian healthcare system as fewer people with wounds will end up in hospital. The Wound CRC estimates that wound healing and management costs the Australian healthcare system $2.85 billion a year, but this is considered a conservative figure and one that covers only the tip of the iceberg.

Griffiths hopes big institutions such as aged and residential care homes will join the clinical service and teleclinic. Some have large percentages of residents who need constant, ongoing wound care. “I know of one aged care home with 38% of residents with chronic wounds,” says Griffiths.

Some of the worst wounds to treat stem from chronic diseases such as diabetes. There are more than 4400 amputations in Australia because of diabetic foot wounds and every 30 seconds a lower limb is lost around the world.

Funded by the Federal Government, the Wound CRC has carried out industry led research since 2010. One research project showed that 78% of patients with venous leg ulcers will heal over a 12-week period by using best practice wound care, including compression bandaging.

Patients in many of the CRC’s studies live with the ulcers for 10 to 20 years. In one case, a patient lived with ulcers for 54 years. At the time, Wound CRC was recruiting patients for a project studying wounds that did not clear up after 12 weeks.

The CRC’s extensive wound healing research stretching over seven years is helping the 433,000 Australian patients who are suffering from chronic wounds at any one time. Their research covers diabetic foot ulcers, burns, skin tears, acute surgical wounds and pressure injuries.

For more information visit woundinnovations.com.au or call 1300 968 637.