ISLAMABAD - A simple procedure that blasts the kidneys with radio waves can cure raised blood pressure, according to researchers.

Currently, about half of those who are being treated do not respond to the drugs, but a study has shown the new procedure can significantly slash raised blood pressure.

It is being trialled in the UK and could be available on the NHS by early next year, the Daily Express reported.

The quick and relatively painless procedure sees a catheter inserted into a vein, which then uses a short burst of radio waves to deactivate nerves in the kidneys.

It is thought this increases blood flow to the organs, reducing activity of the hormone renin, which is itself linked to raised blood pressure.

This latest research, published in the American Heart Association journal Circulation, shows that it is safe and effective in lowering blood pressure up to one year after starting treatment, with no lasting harm to the kidneys or heart.

Hypertension, defined as a blood pressure higher than 140 over 90 millimetres of mercury, is a major risk factor for heart disease, stroke and kidney failure. There are a number of drug treatments available. But many on medication, which can involve as many as three to five types, are still not able to get their blood pressure under control.

Now, study leader Professor Murray Esler, from the Baker IDI Heart and Diabetes Institute in Melbourne, Australia, has shown that these patients can be helped with a zap to the kidneys.

“Studies will soon determine whether this procedure can cure mild hypertension, producing permanent drug-free normalisation of blood pressure,” he said.

The minimally invasive procedure is known as catheter-based renal denervation. It uses a probe passed through the femoral artery in the groin to fire short bursts of intense radio waves at nerves around the kidneys.

The aim is to destroy nerves that may be overactive in patients with hypertension. A total of 82 patients with drug-resistant hypertension took part in the Symplicity HTN-2 trial. All had blood pressure readings of 160 or higher and had taken three or more anti-hypertension drugs. Some had other conditions including diabetes. The findings showed that six months after treatment, systolic blood pressure was reduced by at least 10 millimetres of mercury in 83 per cent of one group of patients. Almost 79 per cent of the same group were able to maintain such reductions for a year.

“Participants’ kidneys were not damaged or functionally impaired. We also found no ill effects on long-term health,” Prof Esler said.

Mysterious source of itchiness found

Scientists have identified that certain nerve cells are specialized to detect itchy sensations, and those receptors don’t detect painful sensations. The finding, recently published in the journal Nature Neuroscience, has resolved a long-standing debate over whether itchiness is just a weird form of pain, Discovery News reported.

Now, researchers could silence these responsible nerve fibers to develop better anti-itch treatments, said Ethan Lerner, a neuroscientist at Harvard University who was not involved in the study.

For decades, why we itch has been a mystery. While some pain nerves have been found to fire in response to itchy stimulants, nerves that responded solely to itch proved elusive. Some researchers even wondered whether itch and pain were always processed by the same nerve fibers, but interpreted by the brain differently, said study co-author Xinzhong Dong, a neuroscientist at Johns Hopkins University. But the urge to scratch seemed different in key ways from the experience of pain. For instance, when a mosquito bites, most people feel a powerful desire to scratch the bite, while the pain of touching a hot stove causes people to recoil, Dong told LiveScience.

To identify cells that sense itch, Dong and his colleagues genetically engineered mice whose nerve cells glowed fluorescent green when firing. The researchers then exposed the mice to irritating compounds, such as histamine and the active ingredient in itching powder, and looked for nerves that fired (and glowed green) as a result.

When the researchers burned out the nerves that lit up, the mice scratched a lot less, suggesting they were less itchy.

But that wasn’t enough to prove that the nerves only sense itch, because in theory those neurons could also sense pain. Therefore, the researchers specifically activated just those itch-detecting nerves in the faces of the mice. The animals then scratched their faces with their back paws, which they only do when itchy.

(When they are in pain, they wipe their faces with their front legs.)

The newly discovered itch nerves sit inside the spine, near the spinal cord, and only innervate locations within the skin. That explains why people feel the urge to scratch their skin, but don’t feel itchy in internal organs, Dong said.

The new findings are important because they provide a target for anti-itch medications, Lerner said.

New blood test to tell how long will you live

Researchers claim to have developed a new controversial `lifespan` test that can tell how long a person will live by determining the rate of ageing. The blood test estimates how fast someone is ageing by measuring the length of microscopic structures at the ends of each chromosome called telomeres, which keep each chromosome from falling apart when cells divide, they said.

Telomeres shorten after each cell division and animal studies have shown that a high percentage of short telomeres in blood cells is associated with a shorter-than-normal life expectancy, which is why blood tests could provide a guide to ageing and life expectancy.

More than 100 Britons have already taken the revolutionary blood test to see how fast they are ageing, and which might be used in the future to indicate statistically how long they have got left to live, it was reported.

The company behind the test believes that thousands will further take the 650 pounds blood check in UK next year, and millions more worldwide will be tested by the end of the decade.

It also expects the test to be used as part of the standard medical check-up required by insurance companies, just as they now ask about family history of disease and whether someone is a smoker or obese.

“We consider that this will become as standard a medical diagnostic test as cholesterol testing is now,” said Stephen Matlin, chief executive of Life Length, which is based in Madrid.

“If you look at cholesterol testing since the early 1980s, in a period of 15 years testing volume went from nothing to about 100 million a year,” Matlin said.

However, some experts have warned that there is still not enough known about telomere testing to provide people with any meaningful medical advice, and one Nobel prize-winner has warned that 99 per cent of people who take the test will not gain any benefit.

“Today there are 500 million cholesterol tests a year. If we do one per cent of this, we are doing well. We hope to be testing millions of people by 2020,” Matlin said.

The company plans to lower the price of the test by 20 per cent a year for the next five years so that it costs no more than about 65 pounds by 2017, bringing it within the price range of millions of new customers.