Nature (journal)

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The bitter taste of sugar prohibition | | Independent Battle of Ideas Blogs.

133856181 300x199 The bitter taste of sugar prohibitionOn Thursday, high-profile science journal Nature published a commentary by three academics, which argued that sugar is a toxin and that it should be subject to similar kinds of public-health interventions as alcohol. In other words, sugar should be taxed and restricted just like booze.

One of the authors, Robert Lustig, runs an obesity clinic at a children’s hospital, part of the University of California, San Francisco. His colleagues and fellow authors, Laura Schmidt and Claire Brindis, are researchers in healthy policy. Lustig has gained an online following since 2009 for a lecture entitled ‘Sugar: the Bitter Truth’ (watch it here). While Lustig’s tone is rather melodramatic, there does appear to be a growing body of evidence linking refined carbohydrates and a group of related symptoms – obesity, fatty liver disease, type-2 diabetes and cardiovascular disease – that come together under the broad umbrella of ‘metabolic syndrome’.

It’s certainly the case that these chronic diseases have increased in importance in recent decades (in part because of the decline of infectious disease). Consumption of refined carbohydrates – particularly sugar – has increased, too. America has a particularly sweet tooth; the average American consumes 131 pounds (about 59 kg) of sugar and high-fructose corn syrup (HFCS) per year, up from 113 pounds per person in 1966. A teaspoon of sugar weighs about 4g, so this amounts to 40 teaspoons per person per day. (And remember, that’s an average – some people are consuming considerably more.)

The UK has a pretty sweet tooth, too. A survey for the Food Standards Agency in Scotland in 2008 found that 17 per cent of children’s calorie intake was coming from ‘non-milk extrinsic sugars’ – that is, table sugar and sugar added to food. That adds up to about 20 teaspoons per child per day.

So, we have rising rates of diseases related to metabolic syndrome alongside increased sugar consumption. Sucrose (the kind used as table sugar) and HFCS are regarded as particularly problematic by many researchers because they are both mad up of two simpler sugars, glucose and fructose. Glucose induces the production of insulin and would seem, therefore, to be a reasonable suspect in problems of insulin resistance and diabetes, with knock-on effects to do with obesity. Fructose, though it sounds healthy because it is also found in fruit, is practically Public Enemy No.1 for some health researchers due to its effects on the liver and in relation to heart disease. Thus, some see the consumption of sucrose and HFCS as a dietary double-whammy that significantly increases the risk of a number of chronic diseases.

But while there is a body of evidence that suggests sugar and HFCS are culprits in some common health problems, the appeal for government action is illiberal and wrong-headed. It’s one thing to advise the population on what may be good or bad for our health. Many people have chosen to quit smoking, for example, for health reasons even though they enjoy it. But it is quite another thing to demand that adults should change their habits at the whim of medical researchers, politicians or campaigners.

How we lead our lives should be our choice. If we enjoy smoking, drinking or sugary foods and drinks, it is up to us to balance up any possible health risk against the pleasures that we may forego. After all, for most people, these chronic health problems are largely diseases of old age.  We may well decide to ‘live fast and die a bit younger’. Yet the trend in recent years has been to take that choice out of our hands – through bans on smoking, for example – or to punish us financially for making the ‘wrong’ choices through what are, effectively, sin taxes. This policy trend robs us of our freedom and infantilises us, reducing valid adult choices to the equivalent of childish misbehaviour.

Brown sugar crystals

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If Lustig and his colleagues are right about sugar, then they should put the arguments forward and convince us. We’re not stupid, and we can take on board sound medical advice (especially if it is not polluted by petty politics). But when it comes to bans, taxes and other restrictions on sugar, we should do sweet FA.

Regulations such as age limits for purchasing proposed

Sugar sugar

Sugar sugar


 

Posted: Feb 1, 2012

Sugar is so toxic that it should be taxed and slapped with regulations like alcohol, some U.S. researchers argue.

In a commentary published in Wednesday’s issue of the journal Nature, doctors from the University of California, San Francisco, say that rising global rates of major killers such as heart disease and Type 2 diabetes aren’t caused by obesity as commonly thought.

It has been suggested that sales of sugary foods and drinks be limited during the school day.It has been suggested that sales of sugary foods and drinks be limited during the school day. (iStock)

Instead, obesity is a marker for those health problems, and sugar is the true culprit, Dr. Robert Lustig, Laura Schmidt and Claire Brindis said.

“We recognize that societal intervention to reduce the supply and demand for sugar faces an uphill political battle against a powerful sugar lobby,” they wrote.

Measures such as smoking bans in public places, the use of designated drivers and the addition of condom dispensers in public washrooms were also battlegrounds that are now taken for granted for public health, the authors said in calling for sugar regulations.

They suggested:

Taxing “added sugar” — any sweetener containing fructose that is added to food in processing, including sugar-sweetened beverages and sugared cereal.

Controlling the location and density of fast-food outlets and convenience stores around schools and offering incentives to open grocery stores and farmers’ markets.

Limiting sales during the school day or designating an age limit to buy drinks with added sugar.

The researchers said sugar meets four criteria for regulation that are largely accepted by public health experts and that were first applied to alcohol. Those criteria are pervasiveness in society, toxicity, potential for abuse and negative impact on society.

Dietitians generally encourage people to eat a nutritious diet without focusing on a single nutrient.

via Tax ‘toxic’ sugar, doctors urge – Health – CBC News.

Your brain on nature | Docs Talk | David Suzuki Foundation.

Photo: Your brain on nature

There are multiple ways in which people can make contact with nature in a mindful way – a 20-minute respite away from the office or classroom in an urban park, community or personal gardening, and many other activities (Credit: David via Flickr).

Alan C. Logan is a graduate of the Canadian College of Naturopathic Medicine and an invited faculty member at Harvard’s School of Continuing Medical Education. His latest book, written in collaboration with Harvard Medical School physician Eva Selhub, explores the connection between nature and human health and happiness. Your Brain, On Nature: The science of nature’s influence on your health, happiness and vitality will be published by John Wiley Inc. in spring 2012.

Docs Talk: What happens to our brains “on nature”?

Dr. Logan: People commonly report that spending time in nature makes them feel better. A series of recent studies provides scientific support for this notion. Sophisticated brain-imaging techniques show that when healthy adults view nature scenes rich in vegetation, areas of the brain associated with emotional stability, empathy, and love are more active. These same pathways are activated when a person looks at pictures of a loved one. In contrast, viewing scenes of the built urban environment produced a significant increase in activity of the amygdala, an area of the brain associated with fear and stress. These findings support previous investigations showing that nature scenes can enhance brain-wave activity in ways that are similar to the benefits of meditation.

Docs Talk: How is day-to-day life preventing our brains from reaping those benefits?

Dr. Logan: There has been a shift away from nature-based recreation in favour of the ubiquitous screen. Even when individuals enter green space, they are often not really “there” in the mindful sense — texting, incoming messages, and eyes fixated upon Smartphones take the brain elsewhere. In many ways we are drowning in a sea of infotoxicity and entertainment media. Extracting ourselves from the information vortex is hard because “information”, even of dubious quality, has a powerful physiological pull. To be clear, technology does wondrous things; it is not “bad”. However, an overuse of gadgetry technology may be a key driver in the dilution of nature’s benefits.

Docs Talk: What is science telling us about the connection between nature and healthy brains?

Dr. Logan: Let me highlight just a few of the important findings of late. Recent studies employing land-use data and satellite technology have reported that access to green space within a kilometre of one’s residence is associated with improved mental health. Indeed, large population studies show that those with the least green space within one kilometre of home have a 25 per cent greater risk of depression and a 30 per cent higher risk of an anxiety disorder. Multiple studies from Japan show spending time in forests can lower stress, improve mental outlook, and lower levels of the stress hormone cortisol. Separate studies have shown similar cognitive-enhancing effects of short periods spent in natural settings. Spending just 20 minutes in vegetation-rich nature has been shown to improve vitality. Given that vitality is defined in psychological lexicon as emotional strength in the face of internal and external oppositions, and living life with enthusiasm and zest, the implications for personal and planetary health are enormous.

Docs Talk: What was the most surprising thing you discovered when researching this book?

Dr. Logan: I was struck by the sheer volume of published research on this topic. What started as a mere trickle of studies in the late 1970s has grown leaps and bounds in recent years. It is amazing how convincing the body of evidence has become that shows nature is a variable capable of influencing cognition and behaviour. To highlight one startling report published in the prestigious journal Lancet, a nationwide study in the United Kingdom found that green space is a profound equalizer of health inequalities. When low income was associated with little access to green space, there were significant health disparities between lower and higher socio-economic brackets. This gap narrowed when low-income individuals had access to green space near their residence. Green space helped to fill in the broad health divide between the affluent and the at-risk.

Docs Talk: What do you recommend people do to get their brains back on nature?

Dr. Logan: We need to push land-use planners and politicians to consistently prioritize access to green space as our cities continue to grow. I am hopeful that the recent scientific evaluations of nature’s mental health benefits will help in this process.
As individuals, we can also take steps to foster a connection with nature, starting with getting out into green space in a mindful way. Paying attention to what you are experiencing in the current moment is the bridge between mere exposure to green space and its full rewards in the sphere of mental health. There are multiple ways in which people can make contact with nature in a mindful way — a 20-minute respite away from the office or classroom in an urban park, community or personal gardening, environmental volunteerism, interaction with animals and pets, and at the far end of the spectrum, adventure and so-called wilderness excursions. Obviously, this involves taking a techno-break and powering down the screen and Smartphone.

Docs Talk: What connection do you think your research has to helping us overcome the many environmental challenges we face?

Dr. Logan: There is every reason to be positive about the ability of renewed nature contact to feed greater concern for the environment. Multiple studies show that actual contact with nature, particularly in childhood, is one of the greatest predictors of pro-environmental attitudes. The good news is that, regardless of age, it is entirely possible to foster greater connectivity with nature by mindful contact with nature — and this enhanced connectivity manifests itself in more pronounced attitudes toward pro-environmental concerns. The missing link is awareness of the vitalizing effect of nature, but thankfully this is teachable. A more potent appreciation of the ability of nature to influence positive mental health can be a catalyst for broad change.

 

diagram of a human digestive system

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(NaturalNews) Overuse and overprescription of antibiotic drugs has become a widely known culprit in causing the emergence of antibiotic-resistant “superbugs,” as well as the onset of digestive and other health problems, caused by the elimination of beneficial gut flora. But a new review published in the journal Nature suggests that such gut flora alterations could be permanent.

Professor Martin Blaser from New York University’s (NYU) Langone Medical Center has been studying the long-term effects of antibiotics on gut flora, which has already confirmed a definitive link between antibiotics and the disruption of beneficial bacteria in the digestive system. But what his research also seems to confirm is the possibility that such disruption might be permanent, at least in some individuals, and thus carry with it lifelong health consequences.

“Early evidence from my lab and others hints that, sometimes, our friendly flora never fully recover,” writes Blaser in his shocking editorial. “These long-term changes to the beneficial bacteria within people’s bodies may even increase our susceptibility to infections and disease. Overuse of antibiotics could be fueling the dramatic increase in conditions such as obesity, type 1 diabetes, inflammatory bowel disease, allergies and asthma, which have more than doubled in many populations.”

Blaser suggests that, even at this preliminary stage, restrictions be put in place to clamp down on the rampant overprescription of antibiotics to young children and pregnant women, a misguided practice that is likely responsible for causing each new generation to “[begin] life with a smaller endowment of ancient microbes than the last.”

If antibiotics truly are responsible for causing a permanent imbalance of gut microbiome in some people, then supplementation with probiotics may also be necessary throughout such individuals’ entire lives in order to simply maintain a normal, healthy balance.

At this point in time, vastly reducing the prescription rates of antibiotics to people of all ages — and particularly to young children and pregnant mothers — is of first priority. Along with this is a much-needed ban on the use of growth hormones and antibiotics in conventional cattle-raising operations, which end up in the food products eaten by millions of Americans every single day.

Report: Antibiotics can permanently destroy gut flora balance, leading to lifelong illness.

Deep Thinking About the Future of Food – NYTimes.com.

A variety of drought-stressed wheat grown by researchers near Obregón, Mexico.Josh Haner/The New York TimesA variety of drought-stressed wheat grown by researchers near Obregón, Mexico.

Trying to tap into the best thinking about the future of global agriculture, as I have tried to do in my work as a reporter, can be an exercise in frustration. Many groups and many bright people go at the problem, but not many of them go at it in a holistic way.

The environmental crowd is worried mainly about the ecological damage from agriculture and is prone to recommend solutions that farmers say would undercut the food supply. Traditional agronomists are mainly worried about supply — and tend at times to recommend fixes that might worsen the environmental damage.

A separate crowd is primarily worried about the inequities in the global food system: that a billion people at the top end are killing themselves eating overly rich diets while a billion poor people live desperate lives circumscribed by malnutrition.

Can’t we figure out how to fix all this at once?

It’s a tall order, but a heartening development in global agricultural policy is that some people are starting to try. Now comes an interesting new installment in the literature of the Big Fix. It’s an analysis by an international team of scientists led by Jonathan A. Foley, director of the Institute on the Environment at the University of Minnesota.

Their paper, “Solutions for a Cultivated Planet,” was released online and is scheduled as the cover article of the Oct. 20 issue of the journal Nature. Dr. Foley is also publishing a piece in the November issue of Scientific American, due on newsstands next week, that summarizes the team’s analysis in layman’s terms.

The group finds, as others have before them, that the challenge of doubling global food production in coming decades can probably be met, albeit with considerable difficulty. The interesting thing to me about the analysis is that it doesn’t treat any of the problems confronting the food system as superior to the others — it treats the environmental problem, the supply problem and the equity problem as equally important, laying out a case that they all need to be tackled at once.

“Feeding nine billion people in a truly sustainable way will be one of the greatest challenges our civilization has ever faced,” Dr. Foley says in the Scientific American article, referring to the projected global population at midcentury. (He outlines some of the links between environmental problems and agriculture in this talk, and his group produced a popular animated clip that gives a sense of the scale of the problems here.)

Many elements of the new paper will be familiar to readers who follow these issues. Yet it is interesting to see these building blocks of a smarter food system spelled out in one paper, with hard numbers attached.

For starters, the group argues that the conversion of forests and grasslands to agricultural use needs to stop now; the environmental damage we are doing chopping down the Amazon far exceeds the small gain in food production, it says.

Next, the paper contends that increases in food supply need to come from existing farmland by a process of intensified production in regions where yields are low: northeastern India, Eastern Europe, parts of South America and large parts of Africa being good examples.

If yields in these regions could be brought to within 75 percent of their known potential using modern farming methods, including fertilizer and irrigation, total global supply of major foodstuffs would expand by 28 percent, the paper found. If yields were brought to 95 percent of their potential, close to those achieved in rich countries, the supply increase would be a whopping 58 percent.

The paper does not say so, but I suspect that either development would be enough to reverse the soaring food prices of recent years.

Another important strategy laid out in the paper is to improve the efficiency of agriculture in places where yields are already high. If farmers in Africa need more fertilizer, farmers in the United States need less.

The paper essentially argues that high yields can be attained with fewer chemicals and less water, which would not only cut pollution but in some cases also cut costs for farmers.

And finally, the paper argues that more of the food we grow needs to wind up on people’s plates. That means cutting food waste, not just the kind so common in Western kitchens but also the tremendous post-harvest losses caused by bad storage conditions in poor countries.

And it means a shift in diets away from meat and dairy products, which are inefficient to produce, and toward plants. The paper acknowledges that a massive transition to vegetarianism is unlikely but argues that even incremental changes — getting many people to move from less-efficient beef to more-efficient chicken, for instance — would make a difference.

The paper studiously avoids taking sides in the ideological wars over the food system. It does not adopt the left-leaning argument that organic production is the answer to the world’s food issues, nor the rightward view that markets will solve all problems.

It does argue for pulling as many good ideas as possible from emerging food movements into the conventional system — but only if they serve the three goals of increasing supply, reducing environmental damage and improving food security.

As a scientific report, not a policy document, the Foley paper does not offer any big new proposals for how to make all these things happen. Many commentators who have studied these issues have come to the conclusion that the barriers are not primarily technical but involve a lack of political will to solve the problems, leading to low public investment in agriculture.

In his Scientific American article, Dr. Foley does make one intriguing proposal. Pointing to the certification system that has encouraged the construction of green buildings, he asks: what about a new certification system for sustainably produced food?

Instead of catering to a single ideological predilection, the way the organic label does now, the new label would be based on a system that awards points for public benefits and subtracts them for environmental harm. Foods produced according to the best practices would get the highest scores, or possibly the highest letter grades. If consumers adopted it, such a certification would put pressure on companies and farmers to clean up their practices.

“This certification would help us get beyond current food labels such as ‘local’ and ‘organic,’ which do not tell us much about what we are eating,” Dr. Foley writes in Scientific American.

I can only imagine the ideological battles that will erupt if this idea is taken seriously. Yet some of the needed elements are already falling into place, like attempts in Europe to measure the carbon footprint of various foods.

If scientists with no axes to grind could manage to keep control of the certification system, using it as a vehicle to apply stringent performance criteria to farming systems while turning the label into a global brand, the world might have a powerful new tool for improving the food supply — and the health of the planet.

A simulated event in the CMS detector, a colli...

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ScienceDaily (May 25, 2011) — Scientists at Imperial College London have made the most accurate measurement yet of the shape of the humble electron, finding that it is almost a perfect sphere, in a study published in the journal Nature on May 25.

The experiment, which spanned more than a decade, suggests that the electron differs from being perfectly round by less than 0.000000000000000000000000001 cm. This means that if the electron were magnified to the size of the solar system, it would still appear spherical to within the width of a human hair.

The physicists from Imperial’s Centre for Cold Matter studied the electrons inside molecules called ytterbium fluoride. Using a very precise laser, they made careful measurements of the motion of these electrons. If the electrons were not perfectly round then, like an unbalanced spinning-top, their motion would exhibit a distinctive wobble, distorting the overall shape of the molecule. The researchers saw no sign of such a wobble.

The researchers are now planning to measure the electron’s shape even more closely. The results of this work are important in the study of antimatter, an elusive substance that behaves in the same way as ordinary matter, except that it has an opposite electrical charge. For example, the antimatter version of the negatively charged electron is the positively charged anti-electron (also known as a positron). Understanding the shape of the electron could help researchers understand how positrons behave and how antimatter and matter might differ.

Research co-author, Dr Jony Hudson, from the Department of Physics at Imperial College London, said, “We’re really pleased that we’ve been able to improve our knowledge of one of the basic building blocks of matter. It’s been a very difficult measurement to make, but this knowledge will let us improve our theories of fundamental physics. People are often surprised to hear that our theories of physics aren’t ‘finished’, but in truth they get constantly refined and improved by making ever more accurate measurements like this one.”

The currently accepted laws of physics say that the Big Bang created as much antimatter as ordinary matter. However, since antimatter was first envisaged by Nobel Prize-winning scientist Paul Dirac in 1928, it has only been found in minute amounts from sources such as cosmic rays and some radioactive substances.

Imperial’s Centre for Cold Matter aims to explain this lack of antimatter by searching for tiny differences between the behaviour of matter and antimatter that no-one has yet observed. Had the researchers found that electrons are not round it would have provided proof that the behaviour of antimatter and matter differ more than physicists previously thought. This, they say, could explain how all the antimatter disappeared from the universe, leaving only ordinary matter.

Professor Edward Hinds, research co-author and head of the Centre for Cold Matter at Imperial College London, said: “The whole world is made almost entirely of normal matter, with only tiny traces of antimatter. Astronomers have looked right to the edge of the visible universe and even then they see just matter, no great stashes of antimatter. Physicists just do not know what happened to all the antimatter, but this research can help us to confirm or rule out some of the possible explanations.”

Antimatter is also studied in tiny quantities in the Large Hadron Collider at CERN in Switzerland, where physicists hope to understand what happened in the moments following the Big Bang and to confirm some currently unproven fundamental theories of physics, such as supersymmetry. Knowing whether electrons are round or egg-shaped tests these same fundamental theories, as well as other theories of particle physics that even the Large Hadron Collider cannot test.

To help improve their measurements of the electron’s shape, the researchers at the Centre for Cold Matter are now developing new methods to cool their molecules to extremely low temperatures, and to control the exact motion of the molecules. This will allow them to study the behaviour of the embedded electrons in far greater detail than ever before. They say the same technology could also be used to control chemical reactions and to understand the behaviour of systems that are too complex to simulate with a computer.

Electron is surprisingly spherical, say scientists following 10-year study.

12th May 2011

An experimental drug helped monkeys with a form of the Aids virus control the infection for more than a year, suggesting it may lead to a vaccine for people, or even a cure.

Researchers said Cytomegalovirus (CMV) works by priming the immune system to quickly attack the HIV virus when it first enters the body, a point at which the virus is most vulnerable.

Dr Louis Picker of the Oregon National Primate Research Centre, whose study appears in the journal Nature, said he thinks it will be possible to have a vaccine ready to test in people within three years.

HIV Aids virus as seen through a microscope: The next step in the vaccine's development will be to test it in clinical trials in humans

HIV Aids virus as seen through a microscope: The next step in the vaccine’s development will be to test it in clinical trials in humans

CMV enables the immune system to be constantly on the alert for HIV.

Researchers used different versions of the vaccine against a monkey form of the Aids virus, SIV (Simian Immunodeficiency Virus) with outstanding results.

More than half the rhesus macaques treated responded to the point where even the most sensitive tests detected no signs of SIV.

To date, most of the animals have maintained control over the virus for more than a year, gradually showing no indication that they had ever been infected.

Unvaccinated monkeys infected with SIV went on to develop the monkey equivalent of Aids, caused by the collapse of their immune systems.

The findings suggest the vaccine could be effective enough to rid the body of immunodeficiency virus completely, according to the scientists writing in the journal Nature.

Conventional antiretroviral therapies are able to control HIV infection, but cannot clear the virus from its hiding places within the immune system’s white blood cells.

Pioneering: Conventional antiretroviral therapies are able to control HIV infection, but cannot clear the virus from its hiding places within the immune system's white blood cells

Pioneering: Conventional antiretroviral therapies are able to control HIV infection, but cannot clear the virus from its hiding places within the immune system’s white blood cells

Dr Picker said: ‘The next step in vaccine development is to test the vaccine candidate in clinical trials in humans.

‘For a human vaccine, the CMV vector would be weakened sufficiently so that it does not cause illness, but will still protect against HIV.’

CMV belongs to the herpes family of viruses, and like other members of the group never leaves the body once an infection has occurred.

An estimated half of all adults in the UK carry CMV but suffer no or few symptoms. The virus is spread through bodily fluids such as saliva and urine.

When symptoms do occur, they are similar to those of flu including a high temperature and swollen glands and tiredness. People with weakened immune systems can have a more severe response.

‘What’s exciting about these findings is that for the first time a vaccine candidate has been able to fully control the virus in some animals,’ said Dr Wayne Koff, chief scientific officer at the International AIDS Vaccine Initiative (IAVI), which helped fund the research.

Koff said the findings also suggested the possibility that the immune system may eventually eliminate the virus altogether.

‘This research gives us potential clues as to how we might design an HIV vaccine for humans that would provide the same type of control,’ he said.

Fresh hope: The findings suggest the vaccine could be effective enough to rid the body of immunodeficiency virus completely

Fresh hope: The findings suggest the vaccine could be effective enough to rid the body of immunodeficiency virus completely

There is no cure for Aids, but cocktails of drugs can keep the disease at bay for many years.

The human immunodeficiency virus that causes Aids infects 33.3million people globally, according to the United Nations agency UNAIDS. It has killed more than 25million people.

Because it is spread in so many ways – during sex, on needles shared by drug users, in breast milk and in blood – there is no single easy way to prevent infection.

A vaccine is the best hope, and many drug companies and scientific research groups are working on various ways to try to develop one.

‘The breakthrough here is in using a viral-delivered vaccine that persists – essentially using an engineered virus to thwart a pathogenic virus,’ said Robin Shattock, a professor of mucosal infection and immunity at Britain’s Imperial College, who was not involved in the research.

‘Before this, scientists had pretty much given up on the idea of a vaccine that could control HIV replication. This puts it firmly back on the agenda.’

Efforts so far to make an Aids vaccine have not been successful, but a 2009 study in Thailand involving 16,000 people showed for the first time that a vaccine could safely prevent HIV infection in a small number of volunteers.

Dr Picker said the next step is to make a weaker version of the CMV virus to make sure it does not cause any problems in people.

‘The concern would be if we move a virus that is not modified that in some small number it might cause disease,’ he said.

AIDS vaccine ‘could remove all traces of disease from sufferers’ | Mail Online.