Headline of the day
Why incest makes us so squeamish (MSNBC)
Randy Newman: What did he know and when did he know it?
Shortness linked to suicide risk
Thursday, 17 Jan 2008 08:11
Tall men are less likely to commit suicide, study finds
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Babies with a short birth length have more than double the risk of a violent suicide attempt as an adult, a new study suggests.
Swedish researchers also found that catch-up growth during childhood does not lessen the impact of short stature at birth.
They studied almost 320,000 Swedish men born between 1973 and 1980, tracking them from birth to the date of attempted suicide, death, emigration or the end of 1999 – whichever came first.
Their findings, published in the Journal of Epidemiology and Community Health, show that short babies of less than 47cm in length were more likely to attempt suicide as adults, regardless of what height they reached in adulthood, compared with babies of normal length.
Short birth length was also linked to violent suicide, defined as hanging; the use of a firearm or knives; jumping from a height or in front of vehicles; and drowning.
Short stature in later life also increased the risk of suicide; men who were normal length babies but who were short in adult life were 55 per cent more likely than tall men to take their own lives.
Premature birth, resulting in short length and low birth weight, increased the risk of violent suicide fourfold.
The researchers suggest that the brain chemical serotonin may be responsible for their findings.
This chemical is crucial to brain development and low levels are linked to impulsivity, aggression and suicidal behaviour.
Levels of the chemical could be affected by premature birth and other factors restricting growth in the womb, the researchers say.
"In the light of our findings related to the association of poor prenatal growth with subsequent suicide attempts, particularly by violent means, and the lack of a modifying effect of postnatal growth on this association, the importance of early intervention has to be emphasised," the study's authors conclude.
You mean the drug companies hide the news when antidepressant drugs don’t work? That makes us feel sad.
Many unfavorable drug studies aren’t published
BOSTON - Nearly a third of antidepressant drug studies are never published in the medical literature and nearly all happen to show that the drug being tested did not work, researchers reported on Wednesday.
And in some of the studies that are published, unfavorable results have been recast to make the medicine appear more effective than it really is, said the research team led by Erick Turner of the Oregon Health & Science University.
Even if not deliberate, this can be bad news for patients, they wrote in their report, published in the New England Journal of Medicine.
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"Selective publication can lead doctors to make inappropriate prescribing decisions that may not be in the best interest of their patients and, thus, the public health," they wrote.
The idea that unfavorable test results get quietly tucked away so nobody will see them -- sometimes call the "file drawer effect" — has been around for years.
The Turner team was able to study the question because the U.S. Food and Drug Administration has a registry in which companies are supposed to log details of their drug tests before the experiments are begun.
They could see which experiments approved by the FDA between 1987 and 2004 were ultimately publicized in the medical literature and the main criteria the researchers planned to measure success.
"It tells you where they placed their bets before they saw the data," Turner said in a telephone interview.
Of the 74 studies that started for the 12 antidepressants, 38 produced positive results for the drug. All but one of those studies were published.
However, when it came to the 36 studies with negative or questionable results, as assessed by the FDA, only three were published and another 11 were turned around and written as if the drug had worked.
"Not only were positive results more likely to be published, but studies that were not positive, in our opinion, were often published in a way that conveyed a positive outcome," said the team.
For example, of the seven negative studies done on GlaxoSmithKline's Paxil, five were never published. The researchers found three studies for GSK's Wellbutrin SR, but the two negative ones never reached print.
There were five studies for Pfizer's Zoloft, but the three showing the drug to be ineffective were not published and a fourth study, ruled as questionable by the FDA, was written and published to make it appear that the drug worked.
A Glaxo spokeswoman said the company posts the data from all of its trials, positive or negative, on the Internet.
"GlaxoSmithKline agrees that public disclosure of clinical trial results for marketed medicines is essential and fully supports registration of all trials in progress," she said.
Pfizer was not immediately available to comment.
Turner and his colleagues did not find out who was to blame for not publishing the studies.
Although the authors and drug company sponsors may not have submitted the unfavorable results for publication, medical journals and their editors may have played a role by deciding they would rather publish favorable results.
"There's an expectation that if you get a positive result, that's what you're supposed to do, and if you get a negative result you have failed," said Turner. "The first impulse is to say, 'I was wrong. Maybe I should move on to something more interesting"' so the results may never get written up.
We knew if we waited long enough, “The Island of Lost Souls” would end up being a documentary
First animal-human embryo trials to go ahead
Mark Henderson, Science Editor of The Times
Experiments to create Britain’s first embryos that merge human and animal material will begin within months after a Government watchdog today approved two research teams to carry out the controversial work.
Scientists at King’s College London and the University of Newcastle-upon-Tyne will now inject human DNA into empty eggs from cows, to create embryos known as cytoplasmic hybrids that are 99.9 per cent human in genetic terms.
The experiments are intended to provide insights into diseases such as Parkinson’s and spinal muscular atrophy by producing stem cells containing genetic defects that contribute to these conditions.
These will be used as cell models for investigating new approaches to treatment and for improving understanding of how embryonic stem cells develop. They will not be used in therapy, and it is illegal to implant them into the womb.
The decision by the Human Fertilisation and Embryology Authority (HFEA) to grant one-year licences to both teams ends more than a year of uncertainty for the researchers, who first applied for permission to start the work in the autumn of 2006.
Last January the authority deferred a decision and launched a consultation on the issue, which reported in September that the public was broadly supportive. In late November it again delayed ruling because of concerns about procedures for obtaining consent from the donors of the human DNA to be used.
While the HFEA was deliberating, the Government first proposed a ban on the creation of human-animal embryos, also known as “cybrids”, then backtracked after a revolt by scientists.
The creation of human-animal embryos will be explicitly permitted by the Human Fertilisation and Embryology Bill currently passing through Parliament, subject to HFEA licensing. An amendment that would have blocked such research was defeated in the House of Lords on Monday by a majority of 172.
Stephen Minger, who leads the King’s team, said yesterday he was delighted that he would finally be able to start the experiments. “I am pleased that the HFEA has finally after a year and a half realised the importance that the work that we and the group from Newcastle have been licensed for,” he said.
“I am grateful to the scientific community, patient organisations and disease charities for all of the support we have received over the past 18 months. Their backing has been invaluable. This shows that the scientific community can be involved in and influence government policy.”
Lyle Armstrong, who leads the Newcastle group, said: “The award of the HFEA licence is great news. We initially applied for approval to use cow eggs as a means to understand the way they can convert skin cells into embryonic stem cells. Finding better ways to make human embryonic stem cells is the long-term objective of our work and understanding reprogramming is central to this.
“Cow eggs seem to be every bit as good at doing this job as human eggs so it makes sense to use them since they are much more readily available, but it is important to stress that we will only use them as a scientific tool and we need not worry about cells derived from them ever being used to treat human disease
The HFEA has attached conditions to each of the one-year licences but these are not expected to be a barrier to either research project.
The Newcastle group has been asked to provide patient consent forms and to obtain approval from the university’s ethics committee before working with DNA from donated skin cells but it has been cleared to start work immediately using DNA from the UK Stem Cell Bank.
It had originally proposed to use human tissue from a commercial US bank but this was rejected because the donors had not given explicit consent for their cells to be used for making cloned embryos that would be destroyed in experiments.
The King’s licence requires Professor Minger to complete an HFEA training course, which is a formality as he has previously held similar licences. It also requires approval from a local ethics committee before work can begin, which is expected to be granted now the HFEA has ruled positively.
Some critics of cybrid embryos have argued that their use is no longer necessary, given the recent development of a reprogramming technique that can turn back the clock on adult tissue to make “induced pluripotent” stem cells with embryo-like properties, but the HFEA licence committee rejected this.
“The committee considered the emergence of new technologies for reprogramming adult somatic [non-reproductive] cells and agreed that, while very promising, these new technologies do not obviate the need for the basic research into differentiation of pluripotential embryonic stem cells as proposed in this application,” it said.
The decision was welcomed by independent stem cell expertts. Professor Robin Lovell-Badge, of the National Institute for Medical Research in London, said: “The HFEA’s decision is excellent as it adds to the arsenal of techniques UK scientists can use to provide understanding and eventually develop therapies for a wide range of devastating genetic diseases.
“The cloning method allows a patient’s cells to be reprogrammed back into early embryos from which valuable embryonic stem cells can be isolated, and it is the latter that will be studied. While scientists may prefer to use human eggs, these are in short supply and preference should rightly be for their use in treating infertility.
“It is logical to use animal eggs to refine techniques, provide knowledge of reprogramming and early development, and understanding of disease mechanisms. Furthermore, while there are new methods of reprogramming adult cells back to pluripotent embryonic stem-like cells, namely induced pluripotent stem cells, it is important to pursue all avenues as we cannot know in advance which will succeed. Besides, a comparative approach often reveals the most.”
Oh yeah, the Olympics are going to love this. We’ve got two words for you. Vertical leap.
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