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Set the brain buzzing, no wires required
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in Brief Heart drug reduces cancer spread risk
Longer heatwaves blamed on Arctic warming READY for a scorcher? It seems our weather is getting slower – and hotter. Arctic warming is aggravating summer heatwaves across Europe and North America, by putting the brakes on atmospheric circulation. Dim Coumou and colleagues at the Potsdam Institute for Climate Impact Research in Germany studied atmospheric circulation in the northern hemisphere from 1979 to 2013 and found that the length and frequency of hot spells in mid-latitudes had increased. They believe this is due to a reduction in the temperature difference between the Arctic, which is warming quickly, and
mid-latitudes, where average warming is slower. This temperature difference drives the west-to-east movement of mid-latitude weather systems, such as the high-pressure systems that bring hot, dry weather in summer. A smaller temperature difference slows these systems down, making the weather persist for longer. Coumou’s team found that the frequency of stalled weather systems in summer has doubled since the onset of rapid Arctic warming around the year 2000 (Science, doi.org/2s6). In many cases, they stop moving for weeks at a time. That can mean long spells of hot weather that dry out soils, kill crops, empty rivers, trigger forest fires – and cause health problems. The team says this effect drove the six-week Russian heatwave of 2010, and the European scorcher of 2003 that killed 70,000 people.
Set the brain buzzing, no wires required IT’S time for a shake-up. There is a new way to stimulate the brain, using tiny vibrating particles. The technique is a twist on deep brain stimulation, which involves sticking electrodes into the brain to prompt neurons to fire. It has shown promise for treating illnesses including Parkinson’s and depression, but can’t be done without invasive surgery. To see if she could take the 18 | NewScientist | 21 March 2015
electrodes out of the picture, Polina Anikeeva at MIT turned to cellular receptors called TRPV1. These make nerve cells fire when exposed to high temperatures or the heat created by eating chillies. What if it were possible to remotely stimulate the receptors? One way of doing this is to inject magnetic nanoparticles into the brain and apply an oscillating magnetic field. As
the jostling nanoparticles align with the field, they give off heat that TRPV1 receptors on neurons pick up – causing them to fire. Anikeeva’s team tested their technique on three mice. A month later, the nanoparticles – which are approved for use in people – were still able to stimulate the brain. The team are now monitoring the mice to see how long the effects last and how safe the technique is in the long term (Science, doi.org/2s4).
CANCER is cruel: sometimes, life-saving surgery to cut out a tumour may help it spread in the body. There could one day be a drug that reduces this risk. A few years ago, a team led by Takashi Nojiri of Osaka University in Japan was exploring whether giving a molecule called atrial natriuretic peptide (ANP) before lung cancer surgery could reduce subsequent heart problems. It did, and it also had another benefit. Two years later, 91 per cent of people treated with ANP were free from secondary tumours, compared with 75 per cent of a control group. The drug makes blood vessel walls less sticky, preventing cancer cells from adhering and squeezing through the walls to form new tumours. ANP occurs naturally in the heart, so this may explain why secondary tumours are rarely found there, says Nojiri (PNAS, DOI: 10.1073/pnas.1417273112).
Spiders find their mummy yummy MOTHERHOOD is no bed of roses, and for some it can be deadly. Regurgitated food is not enough for young Stegodyphus lineatus. These velvet spiders eat their mother, an act called matriphagy, and she doesn’t seem to mind. In fact, she prepares herself for it. Her abdominal tissues start to break down before the young hatch, making her more palatable for when the babies are 2 weeks old (Journal of Arachnology, doi.org/2s8) This meal may give her young a head start in the desert. The mother’s ovaries wait longer before breaking down, says study leader Mor Salomon of the Hebrew University of Jerusalem, Israel, which may let her make more eggs if things go wrong.
in Brief Heart drug reduces cancer spread risk
Longer heatwaves blamed on Arctic warming READY for a scorcher? It seems our weather is getting slower – and hotter. Arctic warming is aggravating summer heatwaves across Europe and North America, by putting the brakes on atmospheric circulation. Dim Coumou and colleagues at the Potsdam Institute for Climate Impact Research in Germany studied atmospheric circulation in the northern hemisphere from 1979 to 2013 and found that the length and frequency of hot spells in mid-latitudes had increased. They believe this is due to a reduction in the temperature difference between the Arctic, which is warming quickly, and
mid-latitudes, where average warming is slower. This temperature difference drives the west-to-east movement of mid-latitude weather systems, such as the high-pressure systems that bring hot, dry weather in summer. A smaller temperature difference slows these systems down, making the weather persist for longer. Coumou’s team found that the frequency of stalled weather systems in summer has doubled since the onset of rapid Arctic warming around the year 2000 (Science, doi.org/2s6). In many cases, they stop moving for weeks at a time. That can mean long spells of hot weather that dry out soils, kill crops, empty rivers, trigger forest fires – and cause health problems. The team says this effect drove the six-week Russian heatwave of 2010, and the European scorcher of 2003 that killed 70,000 people.
Set the brain buzzing, no wires required IT’S time for a shake-up. There is a new way to stimulate the brain, using tiny vibrating particles. The technique is a twist on deep brain stimulation, which involves sticking electrodes into the brain to prompt neurons to fire. It has shown promise for treating illnesses including Parkinson’s and depression, but can’t be done without invasive surgery. To see if she could take the 18 | NewScientist | 21 March 2015
electrodes out of the picture, Polina Anikeeva at MIT turned to cellular receptors called TRPV1. These make nerve cells fire when exposed to high temperatures or the heat created by eating chillies. What if it were possible to remotely stimulate the receptors? One way of doing this is to inject magnetic nanoparticles into the brain and apply an oscillating magnetic field. As
the jostling nanoparticles align with the field, they give off heat that TRPV1 receptors on neurons pick up – causing them to fire. Anikeeva’s team tested their technique on three mice. A month later, the nanoparticles – which are approved for use in people – were still able to stimulate the brain. The team are now monitoring the mice to see how long the effects last and how safe the technique is in the long term (Science, doi.org/2s4).
CANCER is cruel: sometimes, life-saving surgery to cut out a tumour may help it spread in the body. There could one day be a drug that reduces this risk. A few years ago, a team led by Takashi Nojiri of Osaka University in Japan was exploring whether giving a molecule called atrial natriuretic peptide (ANP) before lung cancer surgery could reduce subsequent heart problems. It did, and it also had another benefit. Two years later, 91 per cent of people treated with ANP were free from secondary tumours, compared with 75 per cent of a control group. The drug makes blood vessel walls less sticky, preventing cancer cells from adhering and squeezing through the walls to form new tumours. ANP occurs naturally in the heart, so this may explain why secondary tumours are rarely found there, says Nojiri (PNAS, DOI: 10.1073/pnas.1417273112).
Spiders find their mummy yummy MOTHERHOOD is no bed of roses, and for some it can be deadly. Regurgitated food is not enough for young Stegodyphus lineatus. These velvet spiders eat their mother, an act called matriphagy, and she doesn’t seem to mind. In fact, she prepares herself for it. Her abdominal tissues start to break down before the young hatch, making her more palatable for when the babies are 2 weeks old (Journal of Arachnology, doi.org/2s8) This meal may give her young a head start in the desert. The mother’s ovaries wait longer before breaking down, says study leader Mor Salomon of the Hebrew University of Jerusalem, Israel, which may let her make more eggs if things go wrong.