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Reviews confirm that Medtronic’s spinal treatment “Infuse” provided little benefit

June 18, 2013

In 2011 The Spine Journal took on the morass of hyped scientific papers, multi-million dollar payments to researchers and adverse effects surrounding Medtronic’s Infuse product. As I posted in August 2011

Medtronic is the world’s largest medical device company and Minnesota’s seventh-largest public company based on revenue, which totaled $15.93 billion for the fiscal year that ended April 29. Medtronic’s Infuse product is a bioengineered bone-growth protein that has been used in spinal fusion procedures for the past nine years and is used in about half of the 80,000 anterior lumbar fusion procedures performed every year in the United States.

Now the NY Times reports that 

The controversy reached a climax in 2011, when a medical publication, The Spine Journal, devoted an issue to reports that repudiated the Medtronic-sponsored research, calling it misleading and biased. The journal’s move was significant because it is published by the nation’s biggest group of spine surgeons, the North American Spine Society.

Experts involved in research, like Dr. Zdeblick and Dr. Burkus, defended their work and insisted that their ties to Medtronic had not influenced them. But facing a firestorm, Medtronic agreed in 2011 to provide $2.5 million to Yale University to oversee an independent review of study data.

The resulting examinations, published Monday, involved reviews by two separate teams.

One of the teams, headed by scientists at Oregon Health and Science University in Portland, reported that Infuse appeared to have no advantages over a bone graft and might pose patient risks, including possibly a small added risk of cancer.

The other team, led by researchers at the University of York in England, found that Infuse fused spinal vertebrae more quickly than a bone graft but that the added speed appeared to lack clinical relevance.

Both the British and Oregon teams found no significant difference between Infuse and a bone graft in measures critical to patients, like reducing pain or improving physical function.

…… 

A professor at Yale who oversaw the review, Dr. Harlan M. Krumholz, said that while the two teams had slightly different findings, they pointed in the same direction.

“The general, overall picture is that they failed to find a big benefit,” for Infuse, Dr. Krumholz said. “And they found there might be some harms.”

Doctors and patients, he said, could use the review’s information to decide which treatment was best for them.

Some reviewers also concluded that the Medtronic-financed research had — unwittingly or not — presented a misleading picture.

“Selective reporting or underreporting of outcomes in journal publications may have misrepresented the benefits and harms,” of Infuse, the Oregon group wrote.

The selective reporting or under-reporting or non-reporting of scientific research to suit the commercial interests of the pharmaceutical and medical industries is not likely to disappear anytime soon. And Infuse is still in use and still generates significant revenues for Medtronic.

The review’s results, however, are likely to lead to further drops in Infuse sales. Annual sales of the product, which stood at about $900 million before The Spine Journal’s issue devoted to it, were $528 million in the company’s most recent fiscal year.”

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Reproduction after death: Guppies do it, humans can – but should they?

June 13, 2013

Guppies use stored sperm while humans can use stored sperm. Using the sperm of someone long dead is certainly possible to “create” a new human. The ethical question – if there is one – is the responsibility (whose?) to the child so produced. And this could be even more important if it is also true that the age of the sperm producer at the time of sperm production has an impact on the health of the child. And is there a responsibility to the deceased sperm donor? By agreeing to the storage of sperm does not the donor implicitly consent to the use of that sperm even after his demise unless he explicitly forbids it?

Photo shows guppies.

Guppies are small freshwater fish PHOTO CREDIT: PIERSON HILL.

UCRtoday:

Performing experiments in a river in Trinidad, a team of evolutionary biologists has found that male guppies continue to reproduce for at least ten months after they die, living on as stored sperm in females, who have much longer lifespans (two years) than males (three-four months).

“Populations that are too small can go extinct because close relatives end up breeding with each other and offspring suffer from inbreeding,” said David Reznick, a professor of biology at the University of California, Riverside and the principal investigator of the research project.  “If there are stored sperm, then the real population size is bigger than the number of animals you see.  Also, stored sperm can increase genetic variation in other ways.”

Scientific American:

Is it ethical to use a dead man’s sperm to father a child? Experts are calling for a consensus on policies surrounding this question, which currently vary widely across the country.

It has been possible for a few decades to obtain a man’s sperm after his death and use it to fertilize an egg. Today, requests for postmortem sperm retrieval (PMSR) are growing, yet the United States has no guidelines governing the retrieval of sperm from deceased men, said Dr. Larry Lipshultz, a urologist at Baylor College of Medicine in Texas.

In the absence of government regulations, medical institutions should come up with their own rules so they can handle the time-sensitive and ethically questionable procedures, Lipshultz argued in an editorial published June 5 in the journal Fertility and Sterility. 

Requests for PMSR can come from the wife or parents of a young man who suddenly died in an accident before having a chance to leave a child, and requests can also come from living, terminally ill men who wish to preserve sperm to be used after death.

But the institutions trying to draft a protocol for these situations face a number of ethical concerns. For example, has the deceased consented to have his sperm used for reproduction after he’s gone? Could just anybody request to obtain his sperm? Is it in the best interest of the child to be brought into the world without having a father? …… 

…. PMSR is currently illegal in France, Germany, Sweden and other countries, even with written consent from the deceased. In the United Kingdom, it can be done if there is written consent, and in Israel, the sperm can be retrieved, but then a judge has to decide whether it can be used.

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Biochemical pathway links nail growth to fingertip regeneration

June 13, 2013

We don’t really know why some of our cells keep regenerating and some don’t. Our bodies contain all the information necessary for the growth – or regrowth – or replacement of cells but we do not know – yet – how to trigger or stop such growth. Triggering growth of cells as needed would help us we age and being able to tell cells when to stop multiplying would get rid of our cancers.

We could say that this is a failing of control. All the information necessary is available in us. All the materials necessary are available and all the tools needed are available. But our brains are not capable of giving the specific instructions to grow or to stop to our various cells. If I could I would like to give my knees the signal to regrow some cartilage but I can’t.

This research from the NYU Langone Medical Center is another little step in understanding how regeneration might work.

Wnt activation in nail epithelium couples nail growth to digit regeneration, Makoto Takeo et al, Nature (2013), Published online 12 June 2013, doi:10.1038/nature12214

NYU Press Release: Mammals possess the remarkable ability to regenerate a lost fingertip, including the nail, nerves and even bone. In humans, an amputated fingertip can sprout back in as little as two months, a phenomenon that has remained poorly understood until now. In a paper published today in the journal Nature, researchers at NYU Langone Medical Center shed light on this rare regenerative power in mammals, using genetically engineered mice to document for the first time the biochemical chain of events that unfolds in the wake of a fingertip amputation. The findings hold promise for amputees who may one day be able to benefit from therapies that help the body regenerate lost limbs.  

“Everyone knows that fingernails keep growing, but no one really knows why,” says lead author Mayumi Ito, PhD, assistant professor of dermatology in the Ronald O. Perelman Department of Dermatology at NYU School of Medicine. Nor is much understood about the link between nail growth and the regenerative ability of the bone and tissue beneath the nail. Now, Dr. Ito and team have discovered an important clue in this process: a population of self-renewing stem cells in the nail matrix, a part of the nail bed rich in nerve endings and blood vessels that stimulate nail growth. Moreover, the scientists have found that these stem cells depend upon a family of proteins known as the “Wnt signaling network”—the same proteins that play a crucial role in hair and tissue regeneration—to regenerate bone in the fingertip.
 
“When we blocked the Wnt-signaling pathway in mice with amputated fingertips, the nail and bone did not grow back as they normally would,” says Dr. Ito. Even more intriguing, the researchers found that they could manipulate the Wnt pathway to stimulate regeneration in bone and tissue just beyond the fingertip. “Amputations of this magnitude ordinarily do not grow back,” says Dr. Ito. These findings suggest that Wnt signaling is essential for fingertip regeneration, and point the way to therapies that could help people regenerate lost limbs. An estimated 1.7 million people in the U.S. live with amputations.
 
The team’s next step is to zoom in on the molecular mechanisms that control how the Wnt signaling pathway interacts with the nail stem cells to influence bone and nail growth.

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Posted in Aging, Medicine | Comments Off on Biochemical pathway links nail growth to fingertip regeneration

Shamans versus the witch-doctors: psychologists attack the psychiatrists

May 12, 2013

I have the clear perception that psychiatry has gone too far in trying to attribute all kinds of behaviour to being disabilities. The very influential American Psychiatry Association’s Diagnostic and Statistical Manual of Mental Disorders DSM-5 is soon to be released and even describes grief and temper tantrums as disabilities and yet will no longer recognise Asperger’s! And the psychiatrists have the fundamental concept that all such disabilities are susceptible to medication.

Equally, while I recognise the importance of human psychology as a discipline I am less than impressed by the psychology and behaviour of psychologists and especially the academic gyrations of social psychologists.

So this headline in today’s Guardian conjures up images of a pitched battle between shamans and witch-doctors. I distinguish here between shamans who rely on various secret “medicines” to cure the afflicted, while the witch-doctors are the ones who engage in secret rites to free the patients from the spirits who are haunting them. I suppose in this analogy that the psychiatrists are the shamans and the psychologists are the witch-doctors. But the bottom line of course seems to be that psychologists wantb to adjust behaviour by adjusting other behaviour, and they feel threatened by the psychiatrists’ concept that all unwanted behaviour can be medicated away. The pharmaceutical industry – needless to say – tends to support the psychiatrists (what else?).

The Guardian: Psychiatrists under fire in mental health battle

British Psychological Society to launch attack on rival profession, casting doubt on biomedical model of mental illness.

There is no scientific evidence that psychiatric diagnoses such as schizophrenia and bipolar disorder are valid or useful, according to the leading body representing Britain’s clinical psychologists.

In a groundbreaking move that has already prompted a fierce backlash from psychiatrists, the British Psychological Society’s division of clinical psychology (DCP) will on Monday issue a statement declaring that, given the lack of evidence, it is time for a “paradigm shift” in how the issues of mental health are understood. The statement effectively casts doubt on psychiatry’s predominantly biomedical model of mental distress – the idea that people are suffering from illnesses that are treatable by doctors using drugs. The DCP said its decision to speak out “reflects fundamental concerns about the development, personal impact and core assumptions of the (diagnosis) systems”, used by psychiatry.

Dr. Lucy Johnstone, a consultant clinical psychologist who helped draw up the DCP’s statement, said it was unhelpful to see mental health issues as illnesses with biological causes.

“On the contrary, there is now overwhelming evidence that people break down as a result of a complex mix of social and psychological circumstances – bereavement and loss, poverty and discrimination, trauma and abuse,” Johnstone said. The provocative statement by the DCP has been timed to come out shortly before the release of DSM-5, the fifth edition of the American Psychiatry Association’s Diagnostic and Statistical Manual of Mental Disorders. ….

…… The writer Oliver James, who trained as a clinical psychologist, welcomed the DCP’s decision to speak out against psychiatric diagnosis and stressed the need to move away from a biomedical model of mental distress to one that examined societal and personal factors.

Writing in today’s Observer, James declares: “We need fundamental changes in how our society is organised to give parents the best chance of meeting the needs of children and to prevent the amount of adult adversity.”

But Professor Sir Simon Wessely, a member of the Royal College of Psychiatrists and chair of psychological medicine at King’s College London, said it was wrong to suggest psychiatry was focused only on the biological causes of mental distress. And in an accompanying Observerarticle he defends the need to create classification systems for mental disorder.

“A classification system is like a map,” Wessely explains. “And just as any map is only provisional, ready to be changed as the landscape changes, so does classification.”

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Posted in Behaviour, Humans, Medicine, psychiatry, psychology | Comments Off on Shamans versus the witch-doctors: psychologists attack the psychiatrists

Cheers (hic)! Champagne research at the University of Reading.

May 9, 2013

Back in 2009, Dr Jeremy Spencer from the University of Reading published a paper in the British Journal of Nutrition about how drinking champagne was good for your heart.

image – LiveScience

Research from the University of Reading suggests that two glasses of Champagne a day may be good for your heart and circulation. The researchers have found that drinking Champagne wine daily in moderate amounts causes improvements in the way blood vessels function. …… 

….. Dr Jeremy Spencer, from the Department of Food and Nutritional Sciences said: “Our research has shown that drinking around two glasses of Champagne can have beneficial effects on the way blood vessels function, in a similar way to that observed with red wine. We always encourage a responsible approach to alcohol consumption, but the fact that drinking Champagne has the potential to reduce the risks of suffering from cardiovascular diseases such as heart disease and stroke, is very exciting news.” 

University of Reading

Four years on he is now Professor of Nutritional Biochemistry and Medicine and – presumably – many cases of champagne later, he has just published another paper on the benefits of champagne in improving memory and holding back dementia .

New research shows that drinking one to three glasses of champagne a week may counteract the memory loss associated with ageing, and could help delay the onset of degenerative brain disorders, such as dementia.

Scientists at the University of Reading have shown that the phenolic compounds found in champagne can improve spatial memory, which is responsible for recording information about one’s environment, and storing the information for future navigation. …. 

….. Professor Jeremy Spencer, Department of Food and Nutritional Sciences, University of Reading, said: “These exciting results illustrate for the first time that the moderate consumption of champagne has the potential to influence cognitive functioning, such as memory.  Such observations have previously been reported with red wine, through the actions of flavonoids contained within it. 

“However, our research shows that champagne, which lacks flavonoids, is also capable of influencing brain function through the actions of smaller phenolic compounds, previously thought to lack biological activity. …

The paper is published in Antioxidants and Redox Signalling.

I have a very clear “vision” of what Professor Spencer’s lab might look like. A lot more genteel than a pub or a bar — since it’s champagne! I don’t suppose Prof. Spencer has much difficulty in recruiting post-grads and post-docs (whose alcohol consumption capacity is legendary and insatiable). The Department of Food and Nutritional Sciences boasts that it has over 100 PhD and MPhil students!

We currently have over 100 PhD and MPhil students, who each belong to one or more of our 3 research groups:

  • Food and Bioprocessing Sciences
  • Food Microbial Sciences
  • Human Nutrition

Since 1998, we have enjoyed a 97-100% pass rate. Sponsorship comes from research councils, Government departments, the European Union, charities, industry, the Reading Endowment Trust Fund and overseas scholarships.

Note — a 97 – 100% pass rate!

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Posted in Behaviour, Medicine, Memory, Science | 2 Comments »

Prolific Cardiff Professor cleared of misconduct

April 11, 2013

The Shenanigans at Cardiff University led to an investigation by the University  into alleged research misconduct in the laboratory of its dean of medicine, Prof. BP Morgan. He has now been cleared of any misconduct but one of his former co-workers, Rossen Donev,  has been singled out for the manipulation of images. ( Dr. Donev is listed as a lecturer at Swansea University’s College of Medicine). The investigation seems to have found that Prof. Morgan could not have known about his co-worker’s image manipulation even though he was a co-author. Some 40 papers were investigated and image manipulation was found in 4 instances all by the former researcher. Some of the papers have been retracted.

It is laudable that the source of the misconduct has been identified though there is a tiny hint of  a whitewash and some scapegoating when the only guilty person is no longer at the University and every body else is completely exonerated. Does Prof. Morgan have no responsibility at all for misconduct conducted within his group?  The ubiquitous practice of the head of a lab or research group automatically being included as a co-author is not quite satisfactory when the “leader” takes no responsibility for his soldiers. There is something not quite right when there are “lots and lots of papers published by the Dean, Professor B P Morgan, (172 papers and 35 review articles or chapters since 1998 – giving 207 publications in about 180 months!)”. You can’t just take the credit for authorship of more than a paper a month and then not take any responsibility for any wrongdoing. Apart from Dr. Donev, everybody else seems to have “had Doctor’s papers”!

BBC: The dean of Cardiff University’s school of medicine has been cleared of research misconduct after claims images were manipulated in academic articles. Professor Paul Morgan and other members of his research group were cleared by a formal investigation panel.

But four allegations of image manipulation in articles were upheld against a former staff member. Prof Morgan, who researches diseases, said the actions of one individual had a “profound effect” on his reputation. A clinical academic, the professor heads a team which Cardiff University’s website said is “internationally recognised for its expertise and contribution to the field of complement biology”. He remained in his post during the investigation by the panel, which was chaired by a former Cardiff circuit judge. …. 

…. The inquiry rejected all allegations against Prof Morgan and members of his research team, but upheld four allegations of misconduct against the former university employee.

The panel also said that Prof Morgan – the co-author of the four articles in question – would not have been aware that the individual had included manipulated images in the articles.

Cardiff University said it took allegations of academic research misconduct against staff extremely seriously. “The panel did find that allegations of data manipulation against a former member of university staff were substantiated and recommends that protocols are put in place to ensure that data and original image files are in future viewed and assessed prior to submission for publication,” a spokesperson said. “Cardiff University accepts these findings and recommendations and will now take action to put in place procedures to ensure that incidents of this sort do not recur.” …

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Posted in Academic misconduct, Medicine, UK | 3 Comments »

Indian surrogate mother dies after delivery of child for a Norwegian couple

April 2, 2013

UPDATE – from the Norwegian press—

The surrogate mother bore twins but one of them died after birth.

The Norwegian Embassy in India confirmed that preparations were underway for the other child to be taken to Norway.

The surrogate mother was apparently paid 31,000 Norwegian Kronor (about $6,000) (corrected below)

================================

This report in the Svenska Dagbladet today is disturbing not because there is anything inherently wrong with surrogacy but because it smacks of exploitation – of wealth being used to pass on the risks of childbirth to a “poor” surrogate mother. There are some very gray ethics involved in a “rich” Norwegian couple exploiting the poverty of a “poor” surrogate mother who dies – especially in doing something not permitted in Norway. No doubt the surrogate was paid the “going rate” for surrogacy (about $6,000). But I doubt the surrogate had made any real assessment of the risk of losing her life or that the “contract” had a clause to cover for the death of the surrogate.

Svenska Dagbladet: An Indian woman who was the surrogate for a Norwegian couple died shortly after birth. The woman, who was married and had children of  her own developed Hepatitis E during the pregnancy. 

“Pregnancy and childbirth is unpredictable for us all. Unforseen things can happen and the surrogate contract and the parties should take this into account”, says anthropologist Kristin Engh Førde.

Surrogates are not allowed in Norway and Norwegians make use of egg donation abroad.

The article does not report on the condition of the baby nor on the condition of the surrogate’s own children.

I hope the Norwegian couple get their child — but what is their responsibility for those other children?

I am not sure if the quote from anthropologist Kristin Engh Førde is meant to imply – and I hope it does not – that it is the responsibility of every surrogate mother to accept the risk of dying and contract accordingly.

Would the surrogate have died if she had been giving birth at a Norwegian hospital? Would her Hepatitis E have been treated in time?

Mortality rates are generally low, for hepatitis E is a “self-limiting” disease. …  However, during the duration of the infection (usually several weeks), the disease severely impairs a person’s ability to work, care for family members, and obtain food. Hepatitis E occasionally develops into an acute, severe liver disease, and is fatal in about 2% of all cases. Clinically, it is comparable to hepatitis A, but in pregnant women the disease is more often severe and is associated with a clinical syndrome called fulminant hepatic failure. Pregnant women, especially those in the third trimester, suffer an elevated mortality rate from the disease of around 20%.

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Posted in Behaviour, India, Medicine, Norway | 1 Comment »

The return of Eugenics

March 30, 2013

It is the association of the practice of Eugenics with Adolf Hitler and his Nazis and the stigma which that brings which makes it – at least overtly – politically incorrect and tabu. But it was formally practiced by many governments through the 1900’s and as late as 1975 in Sweden.  But Hitler was also a vegetarian, a teetotaler and a non-smoker. So something more than a “Hitler connection” is needed when discussing eugenics. This recent tweet from Richard Dawkins  together with all the recent developments in genetics and IVF and pre-natal screening got me to wondering as to why there is a perception in some quarters that eugenics is “evil”.

Richard Dawkins@RichardDawkins  “Eugenics”: What’s wrong with a nonrandom choice of a gene your child COULD have got from you at random, anyway, by normal genetic lottery? 9:18 AM – 17 Mar 13

Definition of eugenics: noun [treated as singular]

the science of improving a population by controlled breeding to increase the occurrence of desirable heritable characteristics.

The application of eugenics included genetic screening, birth control, promoting differential birth rates, marriage restrictions, segregation, compulsory sterilization, forced abortions or forced pregnancies and genocide. But the history of the practice of eugenics goes back to infanticide in pre-historic times and we apply it every day without any objections in the management of domestic and wild animals. In the days when we were hunter gatherers – it is thought – infanticide was commonly prevalent:

Joseph Birdsell believed that infanticide rates in prehistoric times were between 15% and 50% of the total number of births, while Laila Williamson estimated a lower rate ranging from 15% to 20%. Both anthropologists believed that these high rates of infanticide persisted until the development of agriculture during the Neolithic Revolution. Comparative anthropologists have calculated that 50% of female newborn babies were killed by their parents during the Paleolithic era. Decapitated skeletons of hominid children have been found with evidence of cannibalism.

The Hitler and the Nazi connotation is certainly part of it but is it primarily the application of coercive measures which today gives eugenics its unsavoury reputation? As practiced in the early 20th century eugenics was applied to humans pretty much as it was for animals – effectively by promoting certain types of matings, preventing others and culling unwanted individuals. I suspect that it is not just the Hitler connection and the coercive treatment of humans which is so objectionable but also that groups of humans were treated en masse as animals for the sake of improvement of the herd.

In today’s world it is perfectly acceptable for couples using IVF to choose – so far as is possible – desirable genetic characteristics of the sperm or egg donor or both. Genetic pre-natal screening can and does lead to abortions if certain criteria are met or others are found wanting. It is effectively culling before birth. Potential surrogate mothers are genetically screened before selection. Genocide and mass rape still take place in conflict situations (Kosovo, Rwanda…) but are universally condemned. We find it perfectly acceptable however that these choices be made by individuals or couples about “their” child. It is taken to be a proper expression of individual rights – though the consequences are mainly borne by the child yet to be born (or not born). But we would find it quite unacceptable today if any government or society would impose these choices on any individual.

It would seem therefore that eugenics is here to stay. As a preventative health measure it is already acceptable if practiced voluntarily by the individuals involved. Selective breeding practiced voluntarily by individuals is also acceptable but is unacceptable if imposed by coercive decree. Enforced sterilisation of those considered mentally or physically defective was a major part of the Eugenics programs in Europe and the US and Australia but the sterilisation of the mentally ill is much rarer now. It seems inevitable that as physical or behavioural or mental characteristics can be connected to specific genes or groups of genes that these characteristics will become part of the criteria for selecting sperm or eggs or for continuing with a pregnancy or not. And even if “voluntary” individual eugenics is already in place today, I am afraid that it is not unthinkable that governments and societies will once again insist on specifying the criteria to be used to improve the common condition. I conclude therefore that it cannot be eugenics which is evil but it is the manner in which it is practiced which can.

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Posted in Behaviour, Evolution, Medicine, Politics | 2 Comments »

Mutation in gene SIRT1 which protects against cancer and heart disease may cause Diabetes type 1

March 15, 2013

I was diagnosed with Diabetes Type 2 a few years ago but a number of friends have children and grandchildren suffering from Diabetes Type 1.  This is a life-long condition and with modern drugs is manageable but not apparently curable. But treatment starts as babies and the children have a tough time in handling all the injections. The causes are not very clear but a genetic origin has long been suspected since the highest prevalence of Diabetes Type 1 is in Northern Europe, particularly in Scandinavia. Incidence varies from 8 to 17 per 100,000 in Northern Europe and the US, with a high of about 35 per 100,000 in Scandinavia to a low of 1 per 100,000 in Japan and China.

Now Danish researchers have found that a mutation in a particular gene  – SIRT1 – may be a prerequisite for the development of Diabetes Type 1.

Identification of a SIRT1 Mutation in a Family with Type 1 Diabetes

Anna Biason-Lauber, Flemming Pociot et al, Cell Metabolism, Volume 17, Issue 3, 448-455, 5 March 2013, 10.1016/j.cmet.2013.02.001

  • Individuals carrying mutation in SIRT1 are susceptible to type 1 diabetes
  • Human SIRT1 regulates the production of nitric oxide and cytokines
  • SIRT1 regulates immune and metabolic function in humans

Summary

Type 1 diabetes is caused by autoimmune-mediated β cell destruction leading to insulin deficiency. The histone deacetylase SIRT1 plays an essential role in modulating several age-related diseases. Here we describe a family carrying a mutation in the SIRT1 gene, in which all five affected members developed an autoimmune disorder: four developed type 1 diabetes, and one developed ulcerative colitis. Initially, a 26-year-old man was diagnosed with the typical features of type 1 diabetes, including lean body mass, autoantibodies, T cell reactivity to β cell antigens, and a rapid dependence on insulin. Direct and exome sequencing identified the presence of a T-to-C exchange in exon 1 of SIRT1, corresponding to a leucine-to-proline mutation at residue 107. Expression of SIRT1-L107P ininsulin-producing cells resulted in overproduction of nitric oxide, cytokines, and chemokines. These observations identify a role for SIRT1 in human autoimmunity and unveil a monogenic form of type 1 diabetes.

ScienceNordic reports:

“Scientists have known for years that type 1 diabetes has a strong genetic component. But this is probably the first time that a mutation has been discovered in a single gene that causes type 1 diabetes,” says Professor Flemming Pociot, MD, a research group leader at Glostrup Hospital, Denmark, who took part in the international study. .. 

It is normally very difficult to locate the right places in the genome as there are some 20,000 different genes in the human body to go through. ”For this reason, scientists often search for defective genes in families where many members are affected by the same disease. That way we can see whether the affected family members share any specific gene mutations,” explains Pociot.

In the new study, the researchers examined an Israeli family in which four members suffered from T1D. Having searched through the family’s genome, they located a mutation in a gene known as SIRT1. ”This gene is incredibly interesting because other studies indicate that it could play a part in prolonging life, and that it can for instance prevent cancer and cardiovascular disease.”

In most T1D patients, the disease is autoimmune, i.e. the patient’s immune defence attacks the body’s own cells. This was also the case with the Israeli patients, and it soon became clear that the defective sirtuin protein was partly responsible for these faults in the immune system. “We compared the cell behaviour in the patients to that of the healthy family members. It turned out that the patients were far more sensitive to some of the factors we know are central in autoimmune diseases,” says the researcher.

They also carried out a series of experiments on mice to see if they could identify the detailed mechanisms behind the defective sirtuin protein.

They noted that the sirtuin proteins appeared to affect the so-called cytokines – a type of protein that plays a key role in the regulation of the immune system.

The researchers’ theory is, simply stated, that the mutated sirtuin proteins cause the cytokines in the immune system to kill the wrong cells, including those that produce the body’s vital hormone insulin.

The lack of insulin, which helps regulate the blood sugar, is one of the hallmarks of T1D.

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Flu vaccine strongly linked to narcolepsy in children

March 9, 2013

I believe that massive public health programs every winter for the consumption of flu vaccines are driven more by commercial rather than medical considerations. Now comes the news that the risk of narcolepsy in children is enhanced 14 times by the use of Pandemrix. Indiscriminate use of flu vaccines – especially with their limited effectiveness  – do a major public disservice by providing ammunition for the “anti-vaccination brigade”. Whether the success rate of the flu vaccines is high enough to justify the expense of mass campaigns is not clear for me. Certainly I am uncomfortable with the links  between pharmaceutical companies and those who authorise mass campaigns of vaccination.

(Reuters) – Growing evidence of a link between GlaxoSmithKline Plc’s pandemic flu vaccine and an increase in narcolepsy cases among children who received it in Europe, is giving pause to health regulators weighing approval of a similar vaccine in the United States.

Data published recently in the British Medical Journal found that children in England who received GSK’s Pandemrix vaccine during the 2009-10 H1N1 swine flu pandemic had a 14-fold heightened risk of developing narcolepsy, a chronic and potentially debilitating sleep disorder that can cause hallucinations, daytime sleepiness and cataplexy, a form of muscle weakness precipitated by strong emotion.

Authors of the study – whose results echo those of similar studies in Sweden, Finland and Ireland – said the data had implications for the approval and use of future vaccines that, like Pandemrix, contain AS03, a new adjuvant, or booster, that turbo-charges the body’s immune response to the vaccine.

Scientists believe AS03 may be the culprit in the narcolepsy cases though they have yet to decipher the precise nature of the association.

…. A 14-member panel of advisors to the FDA voted unanimously in November to recommend the vaccine to protect against bird flu. The panel considered early studies from Europe showing an increase in the number of narcolepsy cases but concluded that the potential benefit of the vaccine outweighed the risk.

Since then, however, new data, including the study results from Britain, suggest the scale and strength of the narcolepsy link could be greater than first thought. At least one committee member would like the FDA to reconvene the panel.

…. According to GSK, some 30 million doses of the vaccine were administered across Europe and 800 people, mostly children, developed narcolepsy. While acknowledging an association, the company says there is insufficient evidence to prove Pandemrix is the cause. ……

I am not sure if the numbers (except the revenues and profits) actually add up.

 

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