When Natalie Coutts’ nephew, sister and uncle died from cancer in the space of five years, doctors were puzzled.

They seemed far too young – her nephew, who died of a brain tumour, was only 6. Her sister died at just 29 from soft-tissue cancer, and her uncle at 49 from pancreatic cancer.

“The doctors told us, ‘It isn’t normal for so many young people in one family to pass away from cancer’,” says Coutts, who is now 41 and lives in Melbourne.

When some of her relatives underwent genetic testing in the early 2000s, they discovered they had Li-Fraumeni syndrome – a rare hereditary condition caused by mutations in a gene called TP53. The mutations, which occur in about 1 in 10,000 people, greatly increase cancer susceptibility. Half of carriers develop cancer by the age of 30, and the overall lifetime risk is almost 100 per cent.

Coutts’ father – who recently died of leukaemia – turned out to be a carrier. So did her aunt, who recently lost her life to lung cancer. Two of her siblings also tested positive – one remains cancer-free and the other died of other causes.

Test quandary

For a long time, Coutts was unsure about doing the genetic test. “I um-ed and ah-ed for five years,” she says. “When you don’t know, you can cling on to the possibility that you might be negative,” she says. “But that limbo is also very unpleasant, so in the end, I decided I needed to know.”

When she finally took the test in 2009, at the age of 33, she was confirmed as having a TP53 mutation. “It was absolutely devastating,” she says.

But now, Coutts’ prospects are looking brighter. In 2012, she joined a trial at the Garvan Institute of Medical Research in Sydney with 29 other people who have Li-Fraumeni syndrome. The aim of the study was to see if having a whole-body MRI scan each year could detect cancers before they turned deadly.

So far, the screening technique has spotted tumours in Coutts’ uterus and kidneys. They turned out to be benign, but Coutts is glad they were picked up and removed anyway. “I don’t care how many times I’m under the knife because I have children and I want to be around for them,” she says. “I want every lump and bump investigated because there’s such a high risk of cancer.”

Medical treadmill

In addition to whole-body MRI, Coutts also has regular colonoscopies, skin checks, breast exams and blood tests. She doesn’t mind feeling like she’s on a medical treadmill because it makes her feel like she is in control. “I always get anxious in the lead-up to each test and think they’re going to find something,” she says. “But then I get screened and told everything’s OK and I can have a break from the GP.”

Coutts recently had her 6-year-old son tested for TP53 mutations and found out he’s not a carrier. “It was the best news ever,” she says. Her 21-year-old daughter is still deciding whether to take the test. “I want it to be her choice because it’s such a big thing to know. Finding out at that age could completely change your outlook on life.”

The Garvan trial has now confirmed that whole-body MRI is effective at spotting cancers in people with Li-Fraumeni syndrome while the tumours are still at an early, curable stage – something Coutts finds reassuring for her and her family.

“I still have a letter from years ago from a doctor who told me there was no guarantee that screening would help me or extend my life,” she says. “But now it’s been proven to work and it’s a huge help – I wouldn’t have it any other way.”

Curable tumours

Family risk

People who have had amputations can control a virtual avatar using their imagination alone, thanks to a system that uses a brain scanner.

, which translate neuron activity into computer signals, have been advancing rapidly, raising hopes that such technology can help people overcome disabilities such as paralysis or lost limbs. But it has been unclear how well this might work for people who have had limbs removed some time ago, as the brain areas that previously controlled these may become less active or repurposed for other uses over time.

at IDC Herzliya, in Israel, and colleagues have developed a system that uses an fMRI brain scanner to read the brain signals associated with imagining a movement. To see if it can work a while after someone has had a limb removed, they recruited three volunteers who had had an arm removed between 18 months and two years earlier, and four people who have not had an amputation.

While lying in the fMRI scanner, the volunteers were shown an avatar on a screen with a path ahead of it, and instructed to move the avatar along this path by imagining moving their feet to move forward, or their hands to turn left or right. The people who had had arm amputations were able to do this just as well with their missing hand as they were with their intact hand. Their overall performance on the task was almost as good as of those people who had not had an amputation.

“Although the amputees’ performance is a little bit behind the control group, the big picture shows they are almost the same level, and still using the missing arm in their brain,” says Cohen, who presented the research at the IEEE EMBS Conference on Neural Engineering last month.

Because the system requires a person to be inside a brain scanner, it would not be possible to use it outside a lab. But Cohen thinks that a new technology called functional near infrared spectroscopy will make it possible to read the same brain signals with portable devices. This may lead to new ways for people who have had limbs removed to control prosthetic devices.

But Dario Farina, of Imperial College London, doesn’t think such a system is likely to be very useful for amputees. “There are alternative techniques that are far superior for prosthetic control,” he says.

The fMRI interface only distinguished four commands: forward, stop, left and right. Prosthetic controllers that work by detecting muscle signals at the stump of the severed limb can distinguish more commands, respond more quickly, and allow the user to control the force or speed.

Farina thinks Cohen’s system could be more useful for locked-in patients, who have no means of communicating except via brain signals. “For other types of patients, this is a good performance, which is promising,” he says.

Read more: Amputees control virtual prosthetic arm using nerve signals

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“If an AI makes mistakes that a human would make, humans will continue to trust that system”

Keep on running. Ultramarathons do take a toll on a runner’s body, breaking down cartilage and even shrinking the brain, but athletes seem to bounce back from both, with joints repairing before the race has even finished.

For many, marathons represent the ultimate fitness challenge. But a minority go much further, taking part in ultramarathons like the , covering 4500 kilometres from the south of Italy to Norway in 64 days.

This race equates to around 100 marathons, with no rest days, prompting researchers to wonder what such long periods of intense exercise would do to the body.

Uwe Schütz at the University Hospital of Ulm in Germany and his colleagues have spent the last six years finding out. In 2009, they followed a group of 44 runners as they ran the nine-week race across Europe. The team took a portable MRI scanner with them, and periodically scanned the legs, feet, heart, brains and cardiovascular systems of the athletes, as well as taking blood and urine samples.

Scanning feet and leg joints every 900 kilometres, Schütz and his team measured the amount of water that was released from the shock-absorbing cartilage between the bones – a sign of whether cartilage is breaking down. They found that the runners’ cartilage seemed to degrade during the first 2500 km of the race.

But after that distance – around 60 marathons – the cartilage seemed to recover, says Schütz, who presented the findings at the in Chicago this week. “It was thought that cartilage could only regenerate during rest,” he says. “We have shown for the first time that it can regenerate during running.”

Brain size

A runner’s joints aren’t the only parts of their body affected. Earlier analyses of the same runners revealed that their brains seemed to temporarily shrink in size by 6 per cent over the course of the race.

The loss may simply be the result of extreme fatigue and undernourishment, but Schütz thinks it could be caused by lack of stimulation. One of the four brain regions that seems to be particularly affected is known to be involved in visual processing. That area may have been massively under-stimulated by 64 days of viewing little other than roads, he says.

Others have suggested that athletes’ brains may to divert energy to regions involved in motivation. “It is hard to explain what’s going on,” says Schütz. “But we do see total recovery after six months.”

Schütz says people who run normal marathons won’t experience the same degradation.

Aerobic exercise is generally beneficial for the brain, helping to stave off depression and dementia.

(Image credit: Helmut Dietz)

The trick could help us worm our way towards better scanners (Image: Monty Rakusen/Getty)

It’s a new magician’s trick, sawing a magnetic field in half – and all you need is a wormhole. Magnetic fields entering it emerge at the other end as if teleported through space. The feat has practical applications too, such as improving MRI scans.

Despite its evocative name, the wormhole is no portal in space-time, but it does allow a magnetic field to disappear in one region and then re-emerge unchanged elsewhere. Alvaro Sanchez at the Autonomous University of Barcelona, Spain, and his colleagues were inspired to create one by a theoretical .

“They modified our earlier mathematical constructions in a very clever way so that an artificial wormhole could be built using present engineering techniques,” says Matti Lassas at the Helsinki University of Technology in Finland, who co-authored the earlier paper.

Sanchez’s team had transferred a magnetic field across space with a length of special tubing that acted as if it were a hose that could carry magnetic fields without them losing strength. But external magnetic fields would be able to distort the fields inside the hose. To look like a wormhole, the tube itself had to be made invisible.

“We needed to make a 3D magnetic cloak to hide the magnetic hose,” Sanchez says. To do that, they used metamaterials – artificial materials that interact in unusual ways with electromagnetic fields and that may some day be deployed to build invisibility cloaks for light.

(Image: Jordi Prat-Camps and Universitat Autònoma de Barcelona)

The team nested the hose inside a sphere of superconducting strips that deflect incoming fields (silver layer in figure above). But that deflection would be detectable, so they placed another sphere, this time of magnetic material, inside the strips to hide the superconductors (gold interior layer).

“We have a very fine-tuned concentration of attraction and repulsion,” Sanchez says. “The whole object is magnetically invisible because of this cancellation.”

The magnetic field, when it pops out of the other end, looks like a magnetic monopole (below) – something not so far detected in nature.

(Image: Jordi Prat-Camps and Universitat Autònoma de Barcelona)

Being able to cloak magnetic fields as they travel across space could help build better MRI scanners, Sanchez says. Wormholes could let multiple magnetic imagers work together without interfering with each other, or could be used to put some distance between bulky sensors and patients – all without changing the background magnetic field MRIs rely on. His team is planning to reach out to local doctors to guide future research.

The magnetic wormhole is an impressive demonstration of the power of metamaterials, Lassas says. “It makes the scientific work on invisibility cloaking a step – or in fact, a leap – closer to real life applications.”

Journal reference: