What can a graphene sandwich reveal about proteins?


Stronger than steel, but only one atom thick – latest research using the 2D miracle material graphene could be the key to unlocking the mysteries around the structure and behaviour of proteins in the very near future.

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Scientists at The University of Manchester and the SuperSTEM facility, which is located at STFC’s Daresbury Laboratory and funded by the Engineering and Physical Sciences Research Council (EPSRC), have discovered that the most fragile, microscopic materials can be protected from the harmful effects of radiation when under the microscope if they are ‘sandwiched’ between two sheets of . The technique could soon be the key to enabling the direct study of every single individual atom in a , something yet to be achieved, and revolutionise our understanding of cell structure, how the immune system reacts to viruses and aid in the design of new antiviral drugs.

Observing the structure of some the tiniest of objects, such as proteins and other sensitive 2D materials, at the atomic scale requires a powerful electron microscope. This is exceptionally difficult because the radiation from the can destroy the highly fragile object being imaged before any useful data can be accurately recorded. However, by protecting fragile objects between two sheets of graphene it means they can be imaged for longer without damage under the electron beam, making it possible to quantitatively identify every single atom within the structure. This technique has proven very successful on the test case of a fragile in-organic 2D crystal and the results published in the journal ACS Nano.

During this research, the team of scientists, which included Sir Kostya Novoselov, who shared a Nobel Prize in Physics in 2010 for exploiting the remarkable properties of graphene, were able to observe the effects of encapsulating a microscopic crystal of another highly fragile 2D material, molybdenum di-sulfide, between two sheets of graphene. They found that they were able to apply a high electron beam to directly image, identify and obtain complete chemical analysis of each and every atom within the molybdenum di-sulfide sheet, without causing any defects to the material through radiation.

The University of Manchester’s Dr Recep Zan, who led the research team, said: “Graphene is a million times thinner than paper, yet stronger than steel, with fantastic potential in areas from electronics to energy. But this research shows its potential in biochemistry could also be just as significant, and could eventually open up all sorts of applications in the biotechnology arena.”

Professor Quentin Ramasse, Scientific Director at SuperSTEM added: “What this research demonstrates is not so much about graphene itself, but how it can impact the detail and accuracy at which we can directly study other inorganic 2D materials or highly fragile molecules. Until now this has mostly been possible through less direct and often complicated methods such as protein crystallography which do not provide a direct visualisation of the object in question. This new capability is particularly exciting because it could pave the way to being able to image every single atom in a protein chain for example, something which could significantly impact our development of treatments for conditions such as cancer, Alzheimer’s and HIV.”

Follow-Up Care Crucial for Pediatric Cancer Survivors.


Today 80 percent of children with cancer survive for five years or longer after their diagnosis, and most young survivors grow up to lead long lives. But many deal with after-effects of cancer for their entire lifetimes. Nearly three-quarters of these childhood cancer survivors will later develop a chronic health problem as a delayed effect of treatment, making long-term health monitoring critical to their well-being.

Pictured: Charles Sklar

Pediatric endocrinologist Charles Sklar directs Memorial Sloan-Kettering’s Long-Term Follow-Up Program, which has screened and managed the health of about 2,000 pediatric cancer survivors since its launch in 1990. Dr. Sklar is an active participant in a national research group known as the Childhood Cancer Survivor Study, which monitors the health of pediatric cancer survivors into adulthood to analyze the late effects of cancer treatment and determine how to better detect and treat them.

In a recent interview, Dr. Sklar discussed the Long-Term Follow-Up Program’s role in raising awareness of these lingering effects and why lifelong vigilance is essential.

Are parents of pediatric survivors typically prepared for dealing with late effects of treatment that can impact their child long-term or for the rest of their lives?

Most families that come to us now have heard of these effects, which is somewhat different than when our program started. Oncologists typically discuss most of these potential late effects at the time of diagnosis.

That being said, when you’re the parent of a child with a life-threatening illness, there’s only a limited amount of information you can take in. And often the survivors themselves are not aware because they may have been very young at the time of diagnosis, so these aren’t things that were necessarily discussed with them directly. That’s something we often need to do when we see them in our clinic.

What are the most common delayed effects of cancer treatment such as chemotherapy or radiation on children?

It’s difficult to generalize because treatments are very different for different diseases, and younger children have different vulnerabilities compared to older children. Endocrine, growth, and reproductive problems are very common. Heart and lung problems certainly do occur, but only in select groups of people, and there are very few people who actually suffer from clinically important heart or lung impairments.

How do you diagnose and treat late effects?

Every patient gets a tailored treatment summary that looks at all the therapies they received – including the types and doses of chemotherapy or radiation – as well as the patient’s gender and age at the time of treatment.

We develop a care plan based both on our own experience as well as published guidelines we were instrumental in developing, and we begin a screening program. Some screenings require a yearly blood test; specialized testing like echocardiograms or pulmonary function testing; or sending patients to experts for tests such as neurocognitive testing.

If the tests continue to be normal, there’s obviously nothing to do but continue the screening. Along the way we educate families and survivors about the need to do many of these tests for the rest of their lives.

If we see abnormalities in our screening tests, we treat them or send the patients to specialists who can treat them or perhaps follow them with more sophisticated testing.

How has research on late effects of cancer treatment changed the way that pediatric cancer patients are now treated after their initial cancer diagnosis?

Many changes in treatment have been informed by these types of studies. It’s important to understand that the full scope of late effects and a complete understanding of their prevalence can take 20 to 30 years to come about, so there’s a lot we don’t know yet.

But now we do know, for example, that radiation to the brain – which used to be a standard treatment for almost all children with leukemia – put these children at risk for learning, growth, and endocrine problems. Today, radiation to the brain is only given to a very tiny fraction of children with leukemia, the most common cancer that we see in children.

Radiation to the chest, particularly for young women with Hodgkin’s disease, has now been associated with a very high risk of breast cancer as well as heart problems for both men and women. So the volume, dose, and even the use of radiation has been reduced among these patients over the last 20-plus years.

Are there any new findings from the Childhood Cancer Survivor Study that you find especially compelling?

One study just coming out looked at the interaction between traditional cardiovascular risk factors like high blood pressure, diabetes, and high cholesterol in patients who had cancer treatments that put them at risk for heart problems, such as radiation to the heart area.

While we knew that these children are at risk for certain kinds of heart problems as they age, now we also know that adding in traditional cardiovascular risk factors increases their cardiovascular risks several fold. Their lifetime risk for heart problems and death from heart disease can be significantly reduced if appropriately managed.

What challenges remain in helping childhood cancer survivors?

We need to educate and train physicians and other health care providers to be experts in survivorship. We now have a fellowship here in pediatric survivorship offering specialized, in-depth training to people who want to have a career in taking care of survivors. It’s just now becoming available as a formal area of medical specialization.

The science of dread: anticipating pain makes it worse


For most people, a chocolate today is better than one tomorrow. Economists refer to this as “future discounting”, where we prefer to have nice things now rather than wait and unpleasant things later rather than now.

Rather be in the waiting room?

But this isn’t always the case in reality. When it comes to a potentially painful experience, like having an operation, many people choose to get it over and done with rather than put it off.

In a new paper published in PLOS Computational Biology, researchers from Imperial College London and University College London explore how this reluctance to wait for pain – a feeling commonly known as dread – changes depending on the timing of the painful event. The researchers wanted to know if dread is worse when pain is more delayed.

The study involved a series of experiments in which pain took the form of brief electric shocks to the back of the hand of 35 participants. Over the course of the experiments, participants could choose to receive shocks soon, or delay them by a certain amount of time, which could range from a few seconds to a quarter of an hour.

A minority chose to wait and receive the shocks further into the future. But 71% of participants opted to receive pain sooner, even if meant it would be worse, because, in half of the experiments, choosing earlier pain resulted in more shocks.

The researchers also compared the size of the delay and the probability a participant would choose the later shock. They found the relationship between the two was best described by what they called “exponential dread”: the bigger the delay, the more likely it was the person would opt for the earlier shock.

The shock experiments were relatively brief, so researchers also looked at what happens when people can delay a painful experience much further into the future. The participants were given a hypothetical scenario, in which they had to schedule an appointment for a painful dental procedure. They were told they could have the procedure “today”, or at a fixed later time. This time varied between participants: it could be 1, 5, 13, 32, 89 or 237 days.

Once again, the participants’ choices suggested dread increases exponentially as people approach a painful event:

These results build on previous work, such as a 2006 study which assumed people experienced constant amount of dread over time, rather than having dread increase with the size of the delay. There are, however, still some questions that remain unanswered.

First, how does dread scales with time? The researchers looked at events that occur over minutes and weeks, but can the same patterns be found at other timescales?

Second, what causes us to experience dread in the first place? The researchers suggest a couple of potential explanations. It might be that the brain processes designed to prepare us for a painful experience overrule other types of behaviour, even if this other behaviour could be beneficial. Alternatively, dread could be a form of “stimulus substitution”, whereby the anticipation of pain triggers the same responses that we experience during an actual pain event.

Even if the causes of dread remain elusive, understanding how people deal with the anticipation pain could help in a number of fields. In particular, it could be useful when assessing options about a potentially painful future event, whether that event is an electric shock, a medical procedure, or your girlfriend finding out you’ve eaten all the chocolates.

It’s 11/12/13 – the last consecutive date for another 90 years.


Briefly this afternoon it’ll be 11/12/13 14:15 and 16 seconds

Today is the 11th day of the 12th month of the 13th year in the millennium and at 14:15 and 16 seconds this afternoon the date and time will briefly read: 11/12/13 14:15.16.

11/12/13 is the last date this century with three consecutive numbers – the next for the UK will be February 1, 2103.

Dubbed ‘noughts and crosses day’ by Ron Gordon, a retired teacher from California who has launched a competition to devise an interesting way to celebrate the day, 11/12/13 is one of a number (no pun intended) of numerical anomalies known as ‘sequential days’.

Sequential days are extremely rare and there are usually a mere handful of them a century – in the UK we won’t see one for another ninety years, though in the US (where they write dates the wrong way around) the last one for nearly a century will occur on the 13th of December next year: i.e. 12/13/14.

Another numerical anomaly are the so-called ‘Odd Days’. There are only six of these days a century and they occur when every number in the date is an odd number. The last such date occurred last month on the 9th of November – or 09/11/13.

Mr Gordon also coined the term ‘Trumpet Day’ to describe the date on the second day of the second month in the twenty-second year i.e: 02/02/22.

We’ll next celebrate trumpet day in 2022 (if people still care about these things). Another trumpet day could occur in the US (where as previously discussed they write the date wrongly) on the 22nd of February 2022 i.e. 2/22/22 – which in the UK will correctly read 22/02/22.

There’s also Square Root Day – 4/4/16 (the last one was on March 3, 2009) and the ‘Ones Upon A Day’ 01/11/11.

All given their names and celebrated by – you guessed it – Ron Gordon. So, are people excited about the unusual date? Not according to the Times of India.

In a report published today they mournfully noted that couples weren’t excited about tying the knot on 11/12/13 noting that bookings ‘especially for weddings’ were ‘abysmal’ in the Nagpur district. Spoilsports.

One fifth of drips ‘are dangerous’


Nurse attending to drip

A fifth of patients on an intravenous drip develop complications because they are given the wrong levels of fluid, according to a review of guidance in England and Wales.

Too much fluid can cause heart failure and too little leads to kidney problems.

The National Institute for Health and Care Excellence (NICE) said doctors and nurses needed better drip training.

Patients’ groups said the scale of the problem was “staggering”.

Thousands of people each year need a drip in hospital. But NICE warns that staff are putting lives in danger due to a lack of education in managing intravenous drips.

It has developed new guidelines for the NHS in England and Wales.

Dr Mike Stroud, a gastroenterology consultant at Southampton University Hospitals NHS Trust, who developed the guidelines, said: “Doctors and other health professionals are not well educated in terms of what a patient needs and that is astonishing really.

“This needs to change.”

Drip chief

Hospitals will also be expected to appoint an “intravenous fluid champion” and patients’ drips will need to be managed and monitored more closely.

Katie Scales, a consultant nurse at Imperial College Healthcare NHS Trust, said: “The majority of patients who receive intravenous fluids do so without complications but this is not the case for every patient.

“This NICE guideline is an important lever for improvement and may ultimately help to save lives.”

Katherine Murphy, the chief executive of the Patients’ Association, said the guidelines were “very welcome” due to the “staggering” figure of one in five patients developing complications.

“It’s essential that all staff receive support and training in the administration of IV fluids and hospitals should ensure time is dedicated to this,” she added.

Dr Mike Durkin, director of patient safety at NHS England, said: “I welcome this new guidance.

“Hospitals across the country need to ensure that the recommendations are implemented as routine practice so that the clinical effectiveness of infusion fluids are maximised and any risks are minimised.”

Supervolcano ‘even more colossal’


Yellowstone hot spring
Hot springs are surface evidence of the huge magma chamber that sits beneath Yellowstone

The supervolcano that lies beneath Yellowstone National Park in the US is far larger than was previously thought, scientists report.

A study shows that the magma chamber is about 2.5 times bigger than earlier estimates suggested.

A team found the cavern stretches for more than 90km (55 miles) and contains 200-600 cubic km of molten rock.

The findings are being presented at the American Geophysical Union Fall Meeting in San Francisco.

Prof Bob Smith, from the University of Utah, said: “We’ve been working there for a long time, and we’ve always thought it would be bigger… but this finding is astounding.”

If the Yellowstone supervolcano were to blow today, the consequences would be catastrophic.

The last major eruption, which occurred 640,000 years ago, sent ash across the whole of North America, affecting the planet’s climate.

Now researchers believe they have a better idea of what lies beneath the ground.

The team used a network of seismometers that were situated around the park to map the magma chamber.

Dr Jamie Farrell, from the University of Utah, explained: “We record earthquakes in and around Yellowstone, and we measure the seismic waves as they travel through the ground.

“The waves travel slower through hot and partially molten material… with this, we can measure what’s beneath.”

Yellowstone ash plume It is unclear when the Yellowstone supervolcano will erupt again

The team found that the magma chamber was colossal. Reaching depths of between 2km and 15km (1 to 9 miles), the cavern was about 90km (55 miles) long and 30km (20 miles) wide.

It pushed further into the north east of the park than other studies had previously shown, holding a mixture of solid and molten rock.

“To our knowledge there has been nothing mapped of that size before,” added Dr Farrell.

The researchers are using the findings to better assess the threat that the volatile giant poses.

“Yes, it is a much larger system… but I don’t think it makes the Yellowstone hazard greater,” explained Prof Bob Smith.

“But what it does tell us is more about the area to the north east of the caldera.”

He added that researchers were unsure when the supervolcano would blow again.

Some believe a massive eruption is overdue, estimating that Yellowstone’s volcano goes off every 700,000 years or so.

Bison The National Park is a biodiversity hotspot in the continental United States

But Prof Smith said more data was needed, because there had only been three major eruptions so far. These happened 2.1 million years ago, 1.3 million years ago and 640,000 years ago.

“You can only use the time between eruptions (to work out the frequency), so in a sense you only have two numbers to get to that 700,000 year figure,” he explained.

“How many people would buy something on the stock market on two days of stock data.”

In another study presented at the AGU Fall Meeting, researchers have been looking at other, more ancient volcanic eruptions that happened along the same stretch of continental plate that Yellowstone’s supervolcano sits on.

Dr Marc Reichow, from the University of Leicester, said: “We looked at a time window of between 12.5 to 8 million years ago. We wanted to know how to identify these eruptions and find out how frequently they happened.”

The team found there were fewer volcanic events during this period than had been estimated, but these eruptions were far larger than was previously thought.

Dr Reichow added: “If you look at older volcanoes, it helps to understand what Yellowstone is likely to do.”

TB resistance is a ‘ticking time bomb’


Increasing resistance to tuberculosis drugs around the world is a “ticking time bomb”, says the World Health Organization (WHO).

It estimates almost 500,000 people around the world have a type of TB which is resistant to at least two of the main types of drugs used to treat the disease.

Ranjhu Zha with her 65 year old mother Parvati, who has extensively drug-resistant TB

But most are not diagnosed and are walking around spreading these more deadly strains.

More than half the cases are in China, Russia and India.

The WHO says the overall number of people developing the disease is falling, but 8.6 million people were diagnosed with TB last year, and more than a million people died from the disease.

Through the hot, winding, cramped streets of Mumbai’s sprawling Dharavi slum, we have come to meet Ranjhu Zha and her family.

The family of five is crammed into a space no more than about 2 sq m.

Ranjhu sits with her son and mother on the floor.

Her mother Parvati is wearing a surgical mask.

She has what is known as an extensively drug-resistant form of TB (XDR-TB).

It is not responding to most of the main drugs used to treat the disease.

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We’re just silently watching this epidemic unfold and spread before our eyes”

Dr Ruth Mcnerny TB Alert

She caught the disease from her 23-year-old grand-daughter Bharati, who died of TB in June.

She was resistant to two of the main drugs used to treat the condition.

“My daughter was as beautiful as a flower,” says Ranjhu.

“But slowly, slowly she wasted away. I remember her always.

“But what is the point in thinking about someone who is no more? She is never coming back.”

Tuberculosis is an airborne disease. It’s very contagious and can spread from person to person by breathing in an infected person’s germs.

The cramped conditions in places like the Dharavi slum create the perfect environment for the fast spread of TB and other diseases.

People are living cheek by jowl and there’s not much ventilation.

Ranjhu says her daughter wasn’t given the full course of treatment when she first developed TB, and that made her resistant to the two main types of TB drugs.

Ranjhu’s mother is now getting treatment from the medical charity Medecins Sans Frontieres.

She says she has not been able to get the right drugs from government schemes.

Rampant misuse of antibiotics

Her treatment includes painful injections every day and will last around two years.

MSF says her treatment costs somewhere in the region of $10,000 (£6,000). Standard TB treatment costs around $50.

Drug-resistant TB

  • Multidrug-resistant TB (MDR TB) is caused by an organism that is resistant to at least isoniazid and rifampin, the two most potent TB drugs.
  • Extensively drug resistant TB (XDR TB) is a rare type of MDR TB that is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs, such as amikacin, kanamycin, or capreomycin).

“There are several drugs used to treat TB,” says Lorraine Rebello, medical services manager at the MSF TB and HIV clinic in Mumbai.

“But when two of the primary drugs that are essential to treating TB – rifampicin and isoniazid – are no longer killing the TB bacteria, then the patient has drug-resistant TB.”

The Indian government’s Revised National TB Control Program aims to provide free TB treatment to every tuberculosis patient in the country.

But the WHO says out of the estimated 64,000 drug-resistant cases in India in 2012, only 16,588 were diagnosed.

Lorraine Rebello puts the rise in cases she has seen down to a number of factors.

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What could happen is progressively multi-drug resistant TB takes over from normal tuberculosis”

Dr Mario Raviglione Director, Global TB programme at the World Health Organization

“We have a huge unregulated private sector,” she says.

“We have doctors who are not properly medically qualified, like Ayurvedic doctors who are treating drug-resistant TB.

“They probably don’t have the knowledge to treat the condition, but they prescribe a cocktail of drugs.

“Some patients are even going to pharmacies without prescription and buying drugs over the counter. So we are seeing a rampant misuse of antibiotics.”

Dr Mario Raviglione, director of the WHO’s Global TB programme, describes the situation as a public health crisis.

“What could happen is progressively multi-drug resistant TB takes over from normal tuberculosis.

“If this happens not only would millions of patients potentially die of this form of TB, but if I look at it from an economic perspective the cost of dealing with millions of potential cases is enormous.”

He describes the fact that 80% of multi-drug resistant TB cases around the world are not being treated as a “ticking time bomb”.

“Killing you slowly”

Dr Ruth Mcnerny, senior lecturer at the London School of Tropical Medicine, who works with TB charity TB Alert, says: “We’re just silently watching this epidemic unfold and spread before our eyes.

TB treatment in developing countries

  • Normal TB treatment takes at least six months to treat and costs around $50 (£30)
  • Multidrug-resistant TB treatment can take at least two years and costs around $2,500 (£1,500)
  • Extensively drug-resistant TB can cost many thousands of dollars to treat. Estimated 45,000 cases globally

“TB is very clever because it kills you very slowly. And while it’s killing you very slowly you’re walking around spreading it.

“The issue of TB is if you get someone on treatment, they’ll become non-infectious quite quickly.

“But if the treatment’s not working because it is a drug-resistant strain, then they stay infected and they stay spreading drug-resistant TB.

“The treatment for drug-resistant TB is very, very difficult and at some stage it becomes impossible.”

In India, the government says it is doing all it can to improve diagnoses and treatment.

Hanmant Chauhan heads the TB programme for the state of Maharashtra.

He says around 8,000 multi-drug resistant TB patients have been treated in the last three years.

“We are taking every step so that every TB affected person gets treatment as soon as possible,” he says.

Tuberculosis symptoms

  • A persistent cough, usually for more than three weeks
  • Night sweats for weeks or months
  • Weight loss
  • Fatigue
  • High temperature
  • Shortness of breath

“We are also trying to see that the disease doesn’t spread. We are trying to make people aware about the precautions and treatment, so that the patients get the treatment and TB gets eradicated soon.”

Back in Ranjhu’s slum her 16-year-old son Santosh is studying for exams.

He sleeps on the floor of his tiny home with his infected grandmother and three other relatives.

He knows he is at high risk of catching this particularly deadly form of TB.

“I do feel scared but what can we do, we only have this one place to stay all together,” he says.

“If she removes the mask which makes her so uncomfortable because it is so hot and stuffy here, there is always a danger we will also catch the disease.”

Could diabetes drug slow Alzheimer’s?


A trial has begun to see whether a drug used to treat diabetes can slow the progression of Alzheimer’s disease.

The study will involve 200 patients with memory problems due to early Alzheimer’s. Laboratory research suggests that the drug, liraglutide, reduces brain inflammation, improving the growth of brain cells and the connections between them.

Patients will be recruited in London – at Imperial College and King’s College – and sites in Oxford, Southampton and Swindon.

One of those on the trial is 65-year-old Geoff Payne. He became concerned about short-term memory loss three years ago and was eventually diagnosed with Alzheimer’s.

“My older brother died of Alzheimer’s at the age of 79,” he said.

“His disease was spotted quite late and I remember him being almost entirely silent and withdrawn at family gatherings.

 Geoff and Sue Payne

“I wish I’d tried to talk more to him about it. When I finally got my diagnosis it confirmed my own suspicions. I have had the disease for three years but fortunately I have not yet declined substantially.

Hope

“My wife and I know what to expect in the years ahead, so we take one day at a time. Hopefully this drug may help.”

Those on the trial will receive a daily injection of liraglutide or a placebo for 12 months. They will have scans and memory tests before and after the treatment.

It’s a decade since the last new treatment for Alzheimer’s was introduced and some major drug trials have failed in recent years.

“New drugs can take decades to filter through and cost billions,” said Dr Paul Edison, Imperial College London, who’s leading the trial.

“Liraglutide is a tried and tested diabetes treatment, so we know it is safe. This trial will show within three years whether it can slow the progression of Alzheimer’s.”

Alzheimer’s Society is providing more than £300,000 towards the project. Dr Doug Brown, Director of Research and Development said: “This exciting study suggests that one of these drugs can reverse the biological causes of Alzheimer’s even in the late stages and demonstrates we’re on the right track.

“We are now funding a major new trial to bring it closer to a position where it can be improving the lives of people with dementia.’

G8 summit

The need for more research and new treatments will be the key focus of the G8 dementia summit in London on Wednesday.

The Department of Health says health ministers will discuss how they can coordinate and accelerate efforts and try to break down barriers between companies, researchers and clinicians.

Dementia is already a significant global issue, and cases are predicted to rise from 44 million to 135 million by 2050 – a reflection of the growing and ageing global population.

It is thought to cost the global economy £370bn ($604bn) each year and there are concerns that future demands could overwhelm some health services.

Artificial sweetener ‘is safe’


Artificial sweetener

The artificial sweetener aspartame is safe and poses no threat to health, European food regulators conclude.

The European Food Safety Authority brought forward its review, planned for completion by 2020, at the request of the European Commission.

Since it came into use in the 1980s, a number of medical studies have questioned aspartame’s safety.

The EFSA says it left “no stone unturned” during its full risk assessment.

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Aspartame has been the sweetener with the biggest ‘conspiracy theory‘ stories ever- ranging from behaviour issues in children to liver damage and cancer – all totally disproven, yet again, by this detailed scientific review”

Catherine Collins Principal Dietitian at St George’s Hospital NHS Trust

As well as looking at the available clinical evidence, the EFSA said it listened to stakeholders and considered over 200 comments submitted to its online public consultation.

Full assessment

Aspartame, which sometimes appears on labels as E951, and its breakdown products are safe for human consumption at current levels of exposure, says the EFSA.

Approximately 200 times sweeter than sugar, the low-calorie sweetener is used in many foods and soft drinks.

An Acceptable Daily Intake, or ADI, is set at 40mg per kg of body weight per day.

This is equivalent to 2800mg for an average British adult. For an average 3-year-old child the amount is around 600 mg.

The only exception is for people suffering from a rare genetic disease phenylketonuria who cannot safely consume aspartame.

For most products containing aspartame, consumption would need to be exceptionally high and regular over a person’s lifetime, in order to exceed the ADI.

Dr Alicja Mortensen, who chaired the EFSA’s aspartame review panel, said: “This opinion represents one of the most comprehensive risk assessments of aspartame ever undertaken.

“It’s a step forward in strengthening consumer confidence in the scientific underpinning of the EU food safety system and the regulation of food additives.”

Catherine Collins, Principal Dietitian at St George’s Hospital NHS Trust, welcomed the findings, saying: “Aspartame has been the sweetener with the biggest ‘conspiracy theory’ stories ever- ranging from behaviour issues in children to liver damage and cancer – all totally disproven, yet again, by this detailed scientific review.”

Ulcer pills linked to B12 deficiency


deficiency

heartburn

Medication used to treat stomach ulcers may cause potentially harmful vitamin B12 deficiency, say experts.

A US study of 200,000 people in the Journal of the American Medical Association found the link.

People who took tablets known as proton pump inhibitors (PPIs) or histamine antagonists (H2RAs) were more likely to lack enough vitamin B12 for good health.

Left untreated, B12 deficiency can lead to dementia and neurological problems.

Continue reading the main story

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Only a minority of patients on long term proton pump inhibitors showed evidence of vitamin B12 deficiency”

Prof Mark Pritchard of the British Society of Gastroenterology

The study authors say doctors should still prescribe these medicines, but that they should weigh possible harms against any benefits in patients who need the drugs for prolonged periods of time.

More investigations are needed to fully evaluate the risk which appears to be in people who take these medications for two or more years, they say.

Link not proof

The Kaiser Permanente researchers found that the link with B12 deficiency increased with dose and was stronger in women and younger age groups.

But the overall risk was still low.

PPIs and H2RAs are commonly prescribed for patients with symptoms of stomach ulcers such as heartburn and indigestion.

The tablets are also widely available to buy without a prescription, ‘over-the-counter’ at pharmacies.

They work by reducing the amount of acid made by your stomach.

Stomach acid is needed for us to absorb vitamin B12 from our food, such as meat, fish and dairy.

If identified, most cases of B12 deficiency can be easily treated by giving supplements or an injection of vitamin B12.

But symptoms, such as lethargy, can be vague and overlooked.

Prof Mark Pritchard of the British Society of Gastroenterology said people should not be concerned by the findings.

“Only patients who had taken these tablets for more than two years were at risk and only a minority of patients on long-term proton pump inhibitors showed evidence of vitamin B12 deficiency.”

He said people taking ulcer medications could ask their GP for a simple blood test to measure vitamin B12 levels if they are worried.