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H5N1 Study



"  H5N1 Study: Experts have delayed a decision on whether controversial research into the H5N1 bird flu virus should be released.
It had been looking at how the work could be released while guarding against its abuse by bioterrorists.
But talks at the World Health Organization in Geneva decided more discussions were needed to see if it could be possible to publish in full.
One of the two journals which want to publish has already agreed to wait for talks to be complete.
H5N1 Study about mutation fears
The controversy is centred on two research papers - one of which was submitted to Science, the other to another leading journal, Nature, last year.
They showed that the H5N1 virus could relatively easily mutate into a form that could spread rapidly among the human population.
The studies prompted the US National Security Advisory Board for Biotechnology (NSABB) to ask both journals last November to redact some sensitive parts of the research, which it believed could be used by terrorists to develop such a virus.
The request caused outcry among some scientists who believed that it was an infringement of academic freedom.
Some pointed out that the scientists had given presentations about their work at conferences and the details were already widely circulated, so redaction would have little purpose.
The scientists who carried out the research, and the journals concerned, have been considering the request and listening to suggestions as to how the research results could be redacted in the scientific journals, but distributed to bona fide researchers who urgently need the information.
The information is vital to develop a vaccine to any human form of bird flu, and it would enable surveillance teams to see if the bird flu virus was mutating into a form that could be transmissible to humans.
But such efforts have been put on hold for four months as governments, scientists and the journals decide what to do.
The Geneva meeting of 22 scientists and journal representatives agreed that publishing only parts of the research would not be helpful, because they would not give the full context of a complete paper.
It agreed to extend a temporary moratorium on research using lab-modified H5N1 viruses, but also recognised that research on naturally occurring virus "must continue".
Dr Keji Fukada, assistant director-general of health security and environment for the WHO, said: "Given the high death rate associated with this virus - 60% of all humans who have been infected have died - all participants at the meeting emphasised the high level of concern with this flu virus in the scientific community and the need to understand it better with additional research.
"The results of this new research have made it clear that H5N1 viruses have the potential to transmit more easily between people underscoring the critical importance for continued surveillance and research with this virus."
Dr Fukada added: "There is a preference from a public health perspective for full disclosure of the information in these two studies. However there are significant public concern surrounding this research that should first be addressed."
Experts will now look at what information is already in the public domain and how that relates to the contents of these research papers.
A further meeting is likely to happen in a couple of months' time.
Nature has said it is happy to wait - if there is a chance it will able to publish in full.
Science's editor Dr Bruce Alberts, had previously said it also wanted to publish full details of the work, unless progress was made on how to circulate details of the findings to scientists."
in BBC

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NHS claims breast implants



" NHS claims about breast implants about 1,000 private patients with them have contacted the NHS in England.
The figure was given by Professor Sir Bruce Keogh, NHS Medical Director, in evidence to the Commons Health Select Committee receive all NHS claims many more to come. 
Last month the NHS in England said it would remove breast implants from private patients but would not replace them. So NHS claims started.
It is thought around 40,000 women in Britain have breast implants, the vast majority of surgery being for breast augmentation performed in the private sector.
Professor Keogh said 745 NHS patients with breast implants had so far been identified but this figure may rise. Most of this surgery was reconstructive following breast cancer. (...)"

in BBC
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First patients shown to improve with embryonic stem cells


"Before treatment, the 51-year-old graphic artist was legally blind, unable to read a single letter on a standard eye chart. She has suffered from Stargardt's disease, the most common form of macular degeneration in young patients, since she was a teenager, and it was getting progressively worse.
A second patient, aged 78, suffered from dry macular degeneration -- the leading cause of blindness in the elderly -- and could not even see well enough to go shopping.
But after being treated with stem cells from a donated human embryo, both women have improved dramatically, researchers said on Monday. Stem cells are master cells that can differentiate into any of the 200 kinds of cells in the human body.
Their results are the first-ever report of the medical use of stem cells taken from human embryos, making them crucial barometers of whether the controversial technique will ever find widespread therapeutic uses.
In a paper published online in The Lancet on Monday, physicians at the University of California, Los Angeles, and scientists at biotechnology company Advanced Cell Technology report that the first two patients in the clinical trial suffered no adverse health effects from the treatment and seem to have benefited from it.
A week after having cells derived from a days-old embryo injected into her eye, the graphic artist could count fingers, and after one month she could read the top five letters on the eye chart. She can see more color and contrast, has started using her computer, and for the first time in years can read her watch and thread a needle. The macular degeneration patient recently went to the mall for the first time in years.
The safety findings, not any vision improvement, is what people should focus on, said Dusko Ilic, senior lecturer in stem cell science at Kings College London, who was not involved in the work.
"If everyone expects that the blind patients will see after being treated ... it will end up as disaster," he said.
Nevertheless, advocates for the blind are already hailing the results. "At last we are seeing fruits of human embryonic stem cell research entering clinical trials," said Peter Coffey, Director of the London Project to Cure Blindness.
Using human embryonic stem cells for research or treatment has incited controversy for ethical and medical reasons. Some opponents argue that because removing stem cells from days-old human embryos almost always destroys the embryo, the technique amounts to murder.
ACT is the only company currently testing human embryonic stem cells in study patients. Last November, stem-cell pioneer Geron announced that it was halting what had been the first-ever clinical trial of the cells-testing them in patients with spinal cord injuries - and leaving the field.
When Robert Lanza, chief scientific officer of ACT, approached ophthalmic surgeon Steven Schwartz of UCLA about leading the clinical trial, Schwartz asked for ethical advice from two of his patients: elderly nuns. They gave him the go-ahead, he said last year.
Even scientists who support stem cell research argue that they could be dangerous to use therapeutically. The very property that makes them so valuable in research - stem cells can morph into any of the kinds of cells in the human body - also makes them risky.
They can form teratomas, a type of tumor that arises when stem cells differentiate into a profusion of cell types. (...) "

in Reuters
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Bioterror fears halt research on mutant bird flu

"Scientists who created a potentially more deadly bird flu strain have temporarily stopped their research amid fears it could be used by terrorists.

In a letter published in Science and Nature, the teams call for an "international forum" to debate the risks and value of the studies.

US authorities last month asked the authors of the research to redact key details in forthcoming publications.
A government advisory panel suggested the data could be used by terrorists.
Biosecurity experts fear an altered, more contagious form of the virus could spark a pandemic deadlier than the 1918-19 Spanish flu outbreak that killed up to 40 million people.
The National Science Advisory Board for Biosecurity (NSABB) recommended key details be omitted from publication of the research, which sparked international furore.
"I would have preferred if this hadn't caused so much controversy, but it has happened and we can't change that," Ron Fouchier, a researcher from Erasmus Medical Center in Rotterdam, told Science Insider.
While the H5N1 strain of bird flu is extremely deadly when caught by humans, its impact has so far been limited because it is not easily transmissible between humans.
But the latest joint research, by Erasmus University in the Netherlands and the University of Wisconsin-Madison in the US, altered the strain and found it was much more easily passed between ferrets.
Two scientific journals now want to publish the research - albeit in redacted form - and are trying to work out with the US government how to make the data accessible to "responsible scientists".
The World Health Organization said in a December statement that limiting access to the research would harm an agreement between its members.
The NSABB is made up of scientists and public health experts, 23 from outside the government, and 18 from within.
It cannot stop publication but makes recommendations to researchers.
The scientists' letter published on Friday argues that knowledge of more infectious strains before they mutate in nature is valuable for public health.
"More research is needed to determine how influenza viruses in nature become human pandemic threats," the statement says, "so that they can be contained before they acquire the ability to transmit from human to human, or so that appropriate countermeasures can be deployed if adaptation to humans occurs."
But some said the 60-day pause on research was not enough.
One critic of the studies, Richard Ebright, a biologist at Rutgers University, told Science Insider that the letter "includes flatly false statements" making assurances about the safety of H1N1 research labs.
Reports say that a meeting debating the research and steps forward could come during a World Health Organization meeting in February."
in BBC
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Do Antiperspirants Cause Breast Cancer?

"Maybe you remember the scary rumors that zipped around the Internet a few years ago claiming antiperspirants and deodorants could cause breast cancer. The claims had several things going for them — the fact that antiperspirants and deodorants are applied in the underarm area, close to the lymph nodes, where cancer cells like to congregate, and in the general vicinity of where most breast tumors develop. Then there were the concerns about parabens and aluminum, both ingredients in these products that are easily absorbed by the skin and which some studies had detected in breast tumors.
Doctors scrambled to help patients understand that the disparate facts did not necessarily coalesce into a coherent whole of cause and effect. Just because the parabens were found in breast tumors, for example, didn’t mean that they triggered the cancer.
The latest research on the matter, published in the Journal of Applied Toxicology, may help to alleviate concerns about underarm products further — or rekindle the worry. U.K. researchers have found that paraben traces are present in the tissue of almost all breast cancer patients, whether or not they use antiperspirants.
Among 160 breast-tissue samples from 40 English mastectomy patients, 99% of samples had traces of at least one paraben, and 60% had traces of five different parabens. Even patients who’d never used underarm products had paraben traces in their breast tissue. That’s not surprising, say the authors, since parabens are found in shampoos, make-up, moisturizers, pharmaceuticals and even some food products, where they are used as a preservative. (If you’re looking for them in your own home, they may be listed as methylparaben, ethylparaben, propylparaben, or butylparaben.)
The new study does not support the idea that parabens cause cancer, despite the incredibly high proportion of patient tissues that contain paraben traces. It’s possible that people without cancer might be equally exposed to the chemicals, so that the tissue levels are no higher among women with cancer than among those who are cancer-free. But the study didn’t include an analysis of breast tissue from women without cancer.
Still, people worry about these chemicals because, in the body, parabens act similar to the female sex hormone, estrogen. Lifelong exposure to estrogen has a reasonably well documented association with breast cancer risk. Some researchers have begun to wonder whether lifelong exposure to parabens might not have a similar effect — and there has been great interest in the last 10 years in testing for such a connection."
in Time
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Alzheimer's: Diet can stop brain shrinking

"A diet rich in vitamins, like magnesium supplements, and fish may protect the brain from ageing while junk food has the opposite effect, doctors say.                  
Elderly people with high blood levels of vitamins and omega 3 fatty acids had less brain shrinkage and better mental performance, a Neurology study found.

Trans fats found in fast foods were linked to lower scores in tests and more shrinkage typical of Alzheimer's.
A UK medical charity has called for more work into diet and dementia risk.
The best current advice is to eat a balanced diet with plenty of fruit and vegetables, not smoke, take regular exercise and keep blood pressure and cholesterol in check, said Alzheimer's Research UK.
The research looked at nutrients in blood, rather than relying on questionnaires to assess a person's diet.
US experts analysed blood samples from 104 healthy people with an average age of 87 who had few known risk factors for Alzheimer's.
They found those who had more vitamin B, C, D and E in their blood performed better in tests of memory and thinking skills. People with high levels of omega 3 fatty acids - found mainly in fish - also had high scores. The poorest scores were found in people who had more trans fats in their blood.
Trans fats are common in processed foods, including cakes, biscuits and fried foods.
The researchers, from Oregon Health and Science University, Portland; Portland VA Medical Center; and Oregon State University, Corvallis, then carried out brain scans on 42 of the participants.
They found individuals with high levels of vitamins and omega 3 in their blood were more likely to have a large brain volume; while those with high levels of trans fat had a smaller total brain volume.
Study author Gene Bowman of Oregon Health and Master of Science University said: "These results need to be confirmed, but obviously it is very exciting to think that people could potentially stop their brains from shrinking and keep them sharp by adjusting their diet." (...) "
in BBC
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Powerful New Painkiller Has Addiction Experts Worried

"Drug companies are working to develop a pure, more powerful version of the nation’s second most-abused medicine, which has addiction experts worried that it could spur a new wave of abuse.
The new pills contain the highly addictive painkiller hydrocodone, packing up to 10 times the amount of the drug as existing medications such as Vicodin. Four companies have begun patient testing, and one of them — Zogenix of San Diego — plans to apply early next year to begin marketing its product, Zohydro.
If approved, it would mark the first time patients could legally buy pure hydrocodone. Existing products combine the drug with nonaddictive painkillers such as acetaminophen.
Critics say they are especially worried about Zohydro, a timed-release drug meant for managing moderate to severe pain, because abusers could crush it to release an intense, immediate high.
“I have a big concern that this could be the next OxyContin,” said April Rovero, president of the National Coalition Against Prescription Drug Abuse. “We just don’t need this on the market.”
OxyContin, introduced in 1995 by Purdue Pharma of Stamford, Conn., was designed to manage pain with a formula that dribbled one dose of oxycodone over many hours.
Abusers quickly discovered they could defeat the timed-release feature by crushing the pills. Purdue Pharma changed the formula to make OxyContin more tamper-resistant, but addicts have moved onto generic oxycodone and other drugs that do not have a timed-release feature.
Oxycodone is now the most-abused medicine in the United States, with hydrocodone second, according to the Drug Enforcement Administration’s annual count of drug seizures sent to police drug labs for analysis.
The latest drug tests come as more pharmaceutical companies are getting into the $10 billion-a-year legal market for powerful — and addictive — opiate narcotics.
“It’s like the wild west,” said Peter Jackson, co-founder of Advocates for the Reform of Prescription Opioids. “The whole supply-side system is set up to perpetuate this massive unloading of opioid narcotics on the American public.”
The pharmaceutical firms say the new hydrocodone drugs give doctors another tool to try on patients in legitimate pain, part of a constant search for better painkillers to treat the aging U.S. population.
“Sometimes you circulate a patient between various opioids, and some may have a better effect than others,” said Karsten Lindhardt, chief executive of Denmark-based Egalet, which is testing its own pure hydrocodone product.
The companies say a pure hydrocodone pill would avoid liver problems linked to high doses of acetaminophen, an ingredient in products like Vicodin. They also say patients will be more closely supervised because, by law, they will have to return to their doctors each time they need more pills. Prescriptions for the weaker, hydrocodone-acetaminophen products now on the market can be refilled up to five times.
Zogenix has completed three rounds of patient testing, and last week it announced it had held a final meeting with Food and Drug Administration officials to talk about its upcoming drug application. It plans to file the application in early 2012 and have Zohydro on the market by early 2013. (...) "
in Time
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Brain Scans Help Predict Alzheimer’s Disease Early

"Alzheimer’s disease has always been difficult to diagnose — the only way to identify it definitively is by autopsying the brain after death — but scientists may now have an easier way to spot the degenerative brain disease long before that, even before symptoms appear, using brain scans.
People who go on to develop symptoms of memory loss and cognitive deficits are more likely to show shrinkage in certain areas of the brain early on, compared with those who don’t develop Alzheimer’s, and such changes can be seen in MRI scans of the brain, report Dr. Bradford Dickerson at the Harvard Medical School and Massachusetts General Hospital and colleagues in the journal Neurology. The team worked with hundreds of brain scans of patients at various stages of Alzheimer’s disease, collected by the Alzheimer’s Disease Neuroimaging Initiative database.
Dickerson’s team had previously identified nine regions of the cortex of the brain that seem to be most affected by the amyloid plaque deposits and disintegration of nerve networks that are the hallmark of Alzheimer’s disease. By studying people’s brain scans over time, they were able to see that these nine brain regions appear to be thinner in people who eventually go on to develop Alzheimer’s — but that it takes many years for this structural difference to show up as symptoms of memory loss or cognitive problems.


Using this brain-size signature as a yardstick, the researchers decided to confirm the correlation by testing the patients’ cognitive abilities three years after a baseline brain scan. Indeed, they found that 21% of participants, who had the thinnest Alzheimer’s-related brain regions but showed no signs of memory problems or other cognitive deficits at the start of the study did show signs of cognitive decline three years later, compared with none of the subjects who did not have the same brain thinning and 7% who showed moderately thinner brain areas.
The brain regions in question are responsible for functions such as higher-level cognition, memory and language, which are all affected by Alzheimer’s, so it makes sense that they would shrink in those developing the disease.
“We’ve known for years that there are certain areas that are affected by the amyloid plaques and tangles that damage the brain,” says Dickerson. “It’s not as if the whole brain is damaged at first; much of the brain is fine at the early stages. But if you just looked at the whole forest, you might miss the signature brain areas affected by the disease. So you have to zoom in and specifically focus on the areas that are affected in people with known dementia.”
The results are critical for helping doctors identify patients earlier in the course of the disease, and that’s important since many experts now believe that intervening at the beginning stages may offer patients the best chance for controlling the brain degeneration that causes symptoms. Many of the drugs that have failed to help patients in the advanced stages of Alzheimer’s, for example, may benefit those who are in the first weeks or months of the condition. (...) "
in Time
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Scientists Find a Black Hole the Size of 21 Billion Suns

"They're huge. They're voracious. They're blacker than a panther on a moonless night. They're black holes, the mind-bending, space-warping cosmic objects with gravity so insanely powerful that even a beam of light that wanders too close will be sucked in, never to emerge. Einstein's theory of general relativity predicted they might exist, but the great physicist himself doubted it would really happen.

Einstein was wrong. Over the past decade or two, black holes have been discovered all over the place — small ones peppered around the Milky Way and huge ones, impressively called "supermassive" black holes, lurking the centers of galaxies. The one at the core of Milky Way weighs as much as a couple of million stars, and it could swallow the sun without even noticing, the way you'd swallow a pistachio.

But that's positively puny compared with the two new black holes, each about 330 million light-years away or so, just announced in the journal Nature. The smaller one, located inside a galaxy known as NGC 3842, is as massive as 9.7 billion suns, and the other, in a galaxy called NGC 4889, is more than twice as large: if you put it on a very large balance, it would take at least 21 billion stars to even things out. Another way to think about things: even the smaller of the two is nearly 30% bigger than the previous record holder, announced last winter, and it would make for a great storyline if astronomers were surprised, amazed, flabbergasted, blown away by the awesome giganticness of these monsters. Truthfully, though, they kind of expected it. "If we infer the existence of quasar black holes of ten billion solar masses at early cosmic times," Harvard theorist Avi Loeb told Nature's Ron Cowen for the journal's online news blog, "we'd better find their counterparts in the present-day Universe."

Loeb is referring to quasars — beacons of light so intensely bright they can be seen halfway across the universe. When astronomers first spotted them in the late 1950s, nobody knew what they were. Nowadays, everyone pretty much agrees that quasars are supermassive black holes at the cores of young galaxies. The holes themselves aren't visible, of course, but when they suck in surrounding matter, the stuff heats up to millions of degrees, sending bursts of energy shooting across the cosmos.

Back when the universe was young, there was plenty of gas floating around to feed these monsters. Nowadays, much of it the gas is gone, and so are the quasars — but the black holes that powered them should, as Loeb says, still be around (where would they go, after all?). Now, thanks to some of the world's most powerful telescopes, astronomers know that indeed they are. While scientists can't see the black holes directly, they can see stars whipping around at high speeds in the two galaxies' cores — and by clocking those speeds carefully, the astronomers can calculate how big and how dense the object they're orbiting must be. In each of these cases, nothing but a supermassive black hole fits the bill.

Such observations are technically difficult, so in one sense the latest black-hole discoveries are extraordinary. Still, astronomers expected to find such things all along, so it might not seem like such a big deal to space experts. Indeed, Martin Rees, the British astronomer royal, dubbed the new results "an incremental step" in the New York Times, with nary a word about shock or awe. If you've got a professional interest in how black holes were born and how they evolved, this is more grist for the mill.

For the rest of us — well, they're just kind of awesome."

in Time
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Unknown Disease Killing Ringed Seals in Alaska


"Scores of ringed seals along the coast of Alaska have fallen victim to a mysterious disease that has been afflicting the area since July.

Ailing seals have been beaching themselves in increasing numbers on the Arctic coastline.  Close to 100 sick seals have been found near the northern city of Barrow, and half have already died.  Other communities in the area have also reported sightings of afflicted seals.

Ringed seals live in the water and on floating ice, and they do not generally come ashore.
Biologists suspect a virus may be to blame.  Stricken seals suffer from bleeding lesions on hind flippers, loss of fur, and skin irritation around the nose and eyes.  But the exact pathogen remains unidentified.  Bruce Woods, a spokesman for the U.S. Fish and Wildlife Service, told Reuters, “We're kind of in the dark at this point.”

The disease may not stop at ringed seals.  Dead walruses and several bearded seals in the area were found with these symptoms as well, though it's unclear if the cases are all linked by the same ailment.  Wildlife officials in Russia and Canada have also reported similarly afflicted animals.

Veterinary care for the sick animals is limited by the remote locations they live in.  Though scientists are collecting the dead seals for sampling and study, sick seals have to battle the illness on their own.  Unfortunately, seals that are weakened are less able to fight off predators, such as polar bears. (...)"

in Time
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Prostate Cancer Screening: What You Need to Know


"A panel of cancer experts is recommending against testing for prostate-specific antigen (PSA), the most commonly used prostate cancer screen, in healthy men.
According to its review of the best available data, the U.S. Preventive Services Task Force (USPSTF) concludes that the potential harms of PSA testing — which include further, more invasive testing that may result in impotence and incontinence — outweigh any benefits in healthy men. The panel is expected to release on Tuesday a comprehensive report detailing the value of PSA testing, but the group's draft recommendation was made public this week.
What does this mean for men who are concerned about prostate cancer? Here's some information that can help you decide whether it's right for you.

What is the PSA test?
The PSA test is a blood test that measures levels of prostate-specific antigen, a protein produced by cells of the prostate gland. It tends to show up on cancer cells, so higher levels of the antigen could be a sign of tumors. Men normally have low levels of PSA, but those levels may rise for reasons unrelated to cancer, which is why a high PSA level alone cannot be used to determine whether a man has cancer or some other benign condition.

What conditions other than prostate cancer can raise PSA levels?
There are many: benign growth of the prostate (the gland typically enlarges with age), infection or inflammation of the prostate, ejaculation, and riding a bicycle can all push PSA levels higher.

Who should get the PSA test?
Currently, there is no major medical group that recommends routine PSA testing, but millions of men over age 50 get it. The American Cancer Society, for example, does not have a specific recommendation for routine screening of healthy men without symptoms of prostate cancer, but it advises otherwise healthy men who have reason for concern about increased prostate risk to begin discussing screening with their doctors at age 50. That's because the risk of prostate cancer tends to increase with age. (...)"

in Time
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Why Scientists Are Smarter than Politicians


"One of the best things about being an artist is that nobody can tell you you're doing things wrong. There's no true or false in a Picasso painting, no yes or no in a Mahler composition. That, of course, is how it should be.

The opposite is true for science — and that's how it should be too. The scientific method is defined by the search for the irreducible truth. The riddle of a disease isn't solved till you've isolated the virus; no particle is fully understood till it's been successfully smashed. It's not for nothing that recent news of a neutrino that may have traveled .0025% faster than light is causing such a stir. If that vanishingly tiny anomaly can't be resolved and disproven, a century of physics could collapse.


But the stone walls between art and science aren't nearly as thick as they seem; indeed, in some ways they're entirely permeable. That's a lesson we badly need to learn if we're going to make sound policy decisions in an era in which science and politics seem increasingly at odds.

In the Oct. 3 issue of TIME, theoretical physicist Lisa Randall of Harvard University made a plea for greater deference to reason in the still-young but already-ugly 2012 presidential campaign. Randall lamented "the fundamental disregard for rational and scientific thinking" in a political culture in which Texas governor Rick Perry can dismiss evolution as "merely a theory that's out there," and Minnesota Congresswoman Michele Bachmann can traffic in poppycock about the HPV vaccine causing mental retardation.

Randall's new book, Knocking on Heaven's Door, takes the case one intriguing step further. The book explores some of the biggest ideas in contemporary physics and how they undergird such everyday matters as risk assessment, logic and even our understanding of beauty. But it's in her chapter on creativity — not a quality always associated with the data-crunching business of science — that she makes her most compelling case against the willful know-nothingism that plagues public debate. (...)"

in Time
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