Diamonds Exist In The Icy Mountains Of Antarctica, say Scientists

Scientists say they have discovered compelling evidence that diamonds exist in the icy mountains of Antarctica.

The researchers have identified a type of rock in the permanently frozen region that is known to contain the precious stones.

However recovering any Antarctic mineral resources for commercial purposes is currently forbidden.

The research is published in the journal Nature Communications.

Diamonds are formed from pure carbon under extreme heat and pressure at depths of about 150km in the Earth's crust.

WHO: Daily sugar intake 'should be halved'

People will be advised to halve the amount of sugar in their diet, under new World Health Organization guidance.

The recommended sugar intake will stay at below 10% of total calorie intake a day, with 5% the target, says the WHO.

The suggested limits apply to all sugars added to food, as well as sugar naturally present in honey, syrups, fruit juices and fruit concentrates.

UK campaigners say it is a "tragedy" that the WHO has taken 10 years to think about changing its advice.

The recommendation that sugar should account for no more than 10% of the calories in the diet, was passed in 2002.It works out at about 50g a day for an adult of normal weight, said the WHO.It is a tragedy that it has taken 10 years for the WHO to think about changing their recommendation on sugar”

However, a number of experts now think 10% is too high, amid rising obesity levels around the world.

Announcing the new draft measures, the WHO said in a statement: "WHO's current recommendation, from 2002, is that sugars should make up less than 10% of total energy intake per day.

"The new draft guideline also proposes that sugars should be less than 10% of total energy intake per day.

"It further suggests that a reduction to below 5% of total energy intake per day would have additional benefits."

Dr Francesco Branca, WHO's nutrition director, told a news conference that the 10% target was a "strong recommendation" while the 5% target was "conditional", based on current evidence."We should aim for 5% if we can," he added.

The plans will now go for public consultation, with firm recommendations expected this summer..

N.H.Khider

Source: BBC

Iron Deficiency May Increase Stroke Risk Through Sticky Blood

Iron deficiency may increase stroke risk by making the blood more sticky, scientists have discovered. Every year, 15 million people worldwide suffer a stroke. Nearly six million die and another five million are left permanently disabled. The most common type, ischaemic stroke, occurs because the blood supply to the brain is interrupted by small clots. In the last few years, several studies have shown that iron deficiency, which affects around two billion people worldwide, may be a risk factor for ischaemic stroke in adults and in children.

Iron deficiency can increase the stickiness of blood cells called platelets, which initiate clotting.

Scientists at Imperial College London have discovered that iron deficiency may increase stroke risk by making the blood more sticky. The findings, published in the journal PLOS ONE, could ultimately help with stroke prevention.

Every year, 15 million people worldwide suffer a stroke. Nearly six million die and another five million are left permanently disabled. The most common type, ischaemic stroke, occurs because the blood supply to the brain is interrupted by small clots.

In the last few years, several studies have shown that iron deficiency, which affects around two billion people worldwide, may be a risk factor for ischaemic stroke in adults and in children. How iron deficiency could raise stroke risk has been a puzzle for researchers.

The Imperial team found that iron deficiency increases the stickiness of small blood cells called platelets, which initiate blood clotting when they stick together. Although a link between iron deficiency and sticky platelets was first discovered almost 40 years ago.

The researchers studied a group of patients with a rare disease called hereditary hemorrhagic telangiectasia (HHT) that often leads to enlarged blood vessels in the lungs, similar to varicose veins. Normally, the lungs' blood vessels act as a filter to remove small clots before blood goes into arteries. In patients with abnormal lung vessels, blood is able to bypass the filter, so small blood clots can travel to the brain.

The patients in the study who were short of iron were more likely to have a stroke. In addition, the researchers looked at platelets in the lab and found that when they treated these with a substance that triggers clotting, platelets from people with low iron levels clumped together more quickly.

Dr Claire Shovlin, from the National Heart and Lung Institute at Imperial College London, said: "Since platelets in the blood stick together more if you are short of iron, we think this may explain why being short of iron can lead to strokes, though much more research will be needed to prove this link.

"The next step is to test whether we can reduce high-risk patients' chances of having a stroke by treating their iron deficiency. We will be able to look at whether their platelets become less sticky. There are many additional steps from a clot blocking a blood vessel to the final stroke developing, so it is still unclear just how important sticky platelets are to the overall process.

R.S

Source: ScienceDaily

Vitamin C 'gives chemotherapy a boost'

Vitamin C has long been used as an alternative cancer therapy but evidence is mixed

High-dose vitamin C can boost the cancer-killing effect of chemotherapy in the lab and mice, research suggests.

Given by injection, it could potentially be a safe, effective and low-cost treatment for ovarian and other cancers, say US scientists.

Reporting in Science Translational Medicine, they call for large-scale government clinical trials.

Pharmaceutical companies are unlikely to run trials, as vitamins cannot be patented.

Vitamin C has long been used as an alternative therapy for cancer.

In the 1970s, chemist Linus Pauling reported that vitamin C given intravenously was effective in treating cancer.

Further studies are needed before we know for sure what benefits high dose vitamin C may have for patients”

However, clinical trials of vitamin C given by mouth failed to replicate the effect, and research was abandoned.

It is now known that the human body quickly excretes vitamin C when it is taken by mouth.

However, scientists at the University of Kansas say that when given by injection vitamin C is absorbed into the body, and can kill cancer cells without harming normal ones.

The researchers injected vitamin C into human ovarian cancer cells in the lab, into mice, and into patients with advanced ovarian cancer.

They found ovarian cancer cells were sensitive to vitamin C treatment, but normal cells were unharmed.

The treatment worked in tandem with standard chemotherapy drugs to slow tumour growth in mouse studies. Meanwhile, a small group of patients reported fewer side-effects when given vitamin C alongside chemotherapy.

Co-researcher Dr Jeanne Drisko said there was growing interest in the use of vitamin C by oncologists.

"Patients are looking for safe and low-cost choices in their management of cancer," she told BBC News. "Intravenous vitamin C has that potential based on our basic science research and early clinical data."

One potential hurdle is that pharmaceutical companies are unlikely to fund trials of intravenous vitamin C because there is no ability to patent natural products.

"Because vitamin C has no patent potential, its development will not be supported by pharmaceutical companies," said lead researcher Qi Chen.

"We believe that the time has arrived for research agencies to vigorously support thoughtful and meticulous clinical trials with intravenous vitamin C."

Dr Kat Arney, science communications manager for Cancer Research UK, said there was a long history of research into vitamin C for treating cancer.

"It's difficult to tell with such a small trial - just 22 patients - whether high-dose vitamin C injections had any effect on survival, but it's interesting that it seemed to reduce the side-effects of chemotherapy," she said.

"Any potential treatment for cancer needs to be thoroughly evaluated in large clinical trials to make sure it's safe and effective, so further studies are needed before we know for sure what benefits high dose vitamin C may have for patients."

N.H.Khider

Source: BBC

Do you have a sweet tooth? Honeybees have a sweet claw

New research on the ability of honeybees to taste with claws on their forelegs reveals details on how this information is processed, according to a study published in the open-access journal, Frontiers in Behavioral Neuroscience.

Insects taste through “Sensilla”, hair-like structures on the body that contain receptor nerve cells, each of which is sensitive to a particular substance. In many insects, for example the honeybee, sensilla are found on the mouthparts, antenna and the tarsi -the end part of the legs. Honeybees weigh information from both front tarsi to decide whether to feed, finds the latest study led by Dr. Gabriela de Brito Sanchez, researcher, University of Toulouse, and Dr. Martin Giurfa, Director of the Research Centre on Animal Cognition, University of Toulouse, France.

Hundreds of honeybees were included in the study. Sugary, bitter and salty solutions were applied to the tarsi of the forelegs to test if this stimulated the bees to extend or retract their tongue,  reflex actions that indicate whether or not they like the taste and are preparing to drink. Results revealed that honeybee tarsi are highly sensitive to sugar: even dilute sucrose solutions prompted the bees to extend their tongue. Measurements of nerve cell activity showed that the part of the honeybee tarsus most sensitive to sugary tastes is the double claw at its end. Also, the segments of the tarsus before the claws, known as the tarsomeres, were found to be highly sensitive to saline solutions.

"Honeybees rely on their color vision, memory, and sense of smell and taste to find nectar and pollen in the ever-changing environment around the colony," says Dr. Giurfa. "The high sensitivity to salts of the tarsomeres and to sugar of the tarsal claws is impressive given that each tarsus has fewer sensilla than the other sense organs. The claw's sense of taste allows workers to detect nectar immediately when they land on flowers. Also, bees hovering over water ponds can promptly detect the presence of salts in water through the tarsomeres of their hanging legs."

But what if honeybees receive contradictory information, for example, about tasty sucrose from the right foreleg, but about water or distasteful caffeine from the left? The central nervous system of honeybees weighs this information from both sides, but unequally: input from the side that is first to taste something tasty or distasteful counts for more. For example, if a bee first tasted sucrose on one side, she would typically extend her tongue and subsequently ignore less attractive tastes on the other. But if the order was reversed, she was around 50% less likely than normally to extend her tongue for sucrose.

Source : science daily

N.H.Khider

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