Prion diseases can be passed on by eating infected tissue

Thursday June 11 2015

CJD is caused by prions (abnormally folded proteins)

“Eating brains helped Papua New Guinea tribe become disease resistant,” The Daily Telegraph reports.

Some of the Fore people, who used to eat the brains of dead relatives as a mark of respect, may have developed resistance to prion diseases such as Creutzfeldt Jacob disease (CJD).

Prion diseases occur in humans and animals, and are caused by a build-up of abnormally folded proteins in the brain. Prion diseases can be passed on by eating infected tissue, such as beef that has been exposed to prions. This is known as bovine spongiform encephalopathy (BSE, or “mad cow disease”). There is currently no cure for prion diseases.

A tribe in Papua New Guinea were nearly wiped out by a prion disease called kuru. The infection was spread as a result of their tradition of eating the brains of deceased relatives at their mortuary feasts. Some people were resistant to the infection, and this was thought to be due to a mutation called V127 in the gene encoding the prion protein.

This study used genetically modified mice to test whether this genetic mutation was protective against kuru and CJD. The tests showed that mice with this genetic mutation were indeed resistant to these prion diseases.

The results suggest that this mutation could be responsible for the kuru resistance seen in the survivors. It is hoped this finding may eventually help to develop effective treatments for prion diseases, but much more research will be needed to get to that point.

Prions

Prions are abnormally folded proteins, which, like viruses, bacteria and fungi, can cause infections, which are (to the best of our knowledge) universally fatal.

Unlike viral, bacterial, fungi or human cells, prions do not contain a nucleus (a core of genetic material). This had led to some debate as to whether we can actually classify a prion as a living organism.

Prions are extremely tough and can withstand extreme heat and cold, and are resistant to all antimicrobial medications. They can also survive in dead tissue. 

Where did the story come from?

The study was carried out by researchers from UCL Institute of Neurology and the Papua New Guinea Institute of Medical Research. It was funded by the UK Medical Research Council.

The study was published in thepeer-reviewed medical journal Nature.

As you would expect, talk of brain-eating cannibals caught most of the media’s attention (and ours as well), but some of the headlines gave a misleading impression.

For example, The Telegraph’s headline that “Eating brains helped Papua New Guinea tribe become disease resistant” is inaccurate. Brain eating did not cause the mutation in the gene that then provided resistance to the disease. In fact eating brains nearly wiped out the tribe as Kuru mainly affected women of childbearing age and children. The tribe was saved by stopping the cannibalism in the late 1950s.

The actual beneficial effect was due to what is called “selection pressure”. This is where people with certain characteristics help them to resist the disease, such as the mutation discussed in the study, as are more likely to survive and have children themselves, leading to more people carrying the mutation.

What kind of research was this?

This was an animal study involving mice. The researchers aimed to further their understanding of prion diseases, such as CJD.

Prion diseases occur in humans and animals, and are caused by an abnormal form of a naturally occurring protein called a prion. The faulty prions replicate and convert other proteins, in a chain reaction. The abnormal prions have a different shape to the normal protein; this makes them more difficult for the body to break down, so they accumulate in the brain. The prions cause progressive brain and nervous problems with communication, behaviour, memory, movement and swallowing. These problems eventually lead to death, and there is currently no cure.

There are different types of prion diseases. Some can be inherited, while others occur by chance through a genetic mutation, and others are passed on to other people during medical procedures using contaminated equipment or body parts, or through eating contaminated food. The disease can take years to develop.

One of these prion diseases is called kuru, and occurred in a remote area in Papua New Guinea. The disease was spread by the custom of eating the brain tissue of relatives after death. Previously, the researchers discovered that some of the people who survived had a genetic variation, which led to the production of a slightly different version of the prion protein. They thought this might be what was protecting these people from the kuru infection. People (and mice) carry two copies of every gene, one inherited from each parent. In these people, one of the copies of the gene carrying instructions for making the prion protein changed, which led to the protein having one of its building blocks (amino acids) altered from guanine (G) to valine (V). This change was called V127.

In this study, the authors wanted to test whether V127 stopped mice from getting prion diseases.

What did the research involve?

Mice were genetically engineered to have the human prion protein. The mice were generated to have the following versions of the prion protein genes:

• two copies of the V127 prion protein gene
• one copy of V127 and one normal copy (G127)
• two copies of the normal G127 form of the gene

Each group of mice were individually injected into the brain with infectious tissue from different sources. The tissue used came from four people who had kuru, two people with variant CJD and 12 people with classical CJD.

The researchers then looked at which mice went on to develop the prion diseases.

Types of CJD

Different types of CJD include:

• Sporadic CJD – this is the most common type of CJD, accounting for around 8 in every 10 cases, although it is still very rare; it is unknown what causes sporadic CJD.
• Variant CJD – this is the type of CJD associated with bovine spongiform encephalopathy (BSE or “mad cow disease”), though not everyone exposed to BSE-infected meat will go on to develop vCJD.
• Familial or inherited CJD – This very rare form of CJD is caused by an inherited mutation (abnormality) in the gene that produces the prion protein.

What were the basic results?

Mice with two copies of V127 were completely resistant to infection from all 18 human prion disease cases tested. Mice with one copy of V127 were resistant to kuru and classical CJD, but not variant CJD. Mice with both copies of the normal G127 gene were infected by all of the prion diseases tested.

Variant CJD is the form thought to be caused by consuming meat infected with bovine spongiform encephalopathy (BSE), while sporadic and familial CJD is not. These last two types are often grouped together as “classic CJD”.

How did the researchers interpret the results?

The researchers concluded that the V127 gene appears to give resistance to prion disease. They say that “understanding the structural basis of this effect may therefore provide critical insight into the molecular mechanism of mammalian prion propagation”. This could then lead to the development of treatments against such diseases.

Conclusion

This interesting piece of research has found that a mutation in the gene carrying the instructions for making the normal prion protein can prevent infection with prion diseases such as CJD and kuru in a mouse model.

This mutation had been initially found in survivors of the kuru prion disease in Papua New Guinea, so this supports the theory that this mutation could be why these people survived. The presence of the disease would have “naturally selected” people who carried any genetic variations or other characteristics that protected them from the disease. This means these people would be more likely to have children and pass on this resistance.

As this research was done on mice, the usual caveats apply: that the results may not be found in humans. However, it does support the findings we have from a natural disease epidemic in humans, and it would be unethical to carry out human experiments to test the theory.

This is not the first genetic variation linked to resistance to prion diseases, but adds to what is known about them. It is hoped this greater understanding may enable future research to develop effective treatments for prion diseases, as there are none at present.

If you or a relative have been affected by a prion disease, counselling is available at the National Prion Clinic. This can be in person or over the phone.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

blood pressure

 
 

Victorino Chua

Victorino Chua
The Filipino father-of-two was first arrested in January 2012
Nurse Victorino Chua, found guilty of murdering and poisoning patients at Stepping Hill Hospital, has been jailed for a minimum of 35 years.
Chua killed Tracey Arden, 44, and Derek Weaver, 83, at the hospital in Stockport by injecting insulin into saline bags and ampoules.
The father-of-two was convicted on Monday following a three-month trial.
Judge Mr Justice Openshaw described Chua as an "experienced nurse who used cunning" to poison patients.
He was found guilty of tampering with saline bags and ampoules while working on two acute wards at the hospital in Greater Manchester, in June and July 2011.
These were unwittingly used by other nurses, causing a series of insulin overdoses to mainly elderly victims.
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Relatives of Derek Weaver described Chua as 'evil' and said they were 'delighted' with the verdict
Detectives described Chua as a narcissistic psychopath.
His victims' families were at Manchester Crown Court as Chua was told he would serve at least 35 years in prison before being considered for parole.
Speaking outside court after the verdict, Mr Weaver's sister, Lynda Bleasdale, said: "My sister had a heart attack the day before Derek died. Seeing all the stress of it was obviously a contributory factor to that."
She said Chua "obviously enjoyed watching people suffer".
Gary Arden, whose sister Tracey was murdered by Chua, said he felt "surprisingly nothing" for his sister's killer.
He added: "He's been sentenced and the important thing is he's not able to do this to anybody else."
Tracey Arden and Derek Weaver
Chua was found guilty of murdering Tracey Arden and Derek Weaver
Judge Openshaw said it was "strikingly sinister and truly wicked" that Chua did not personally administer the insulin to most of the patients, so it was left to chance which of them were poisoned.
He said Chua poisoned Jack Beeley, 72, to "shut up a patient who he found particularly troublesome".
Grant Misell, 41, was left brain damaged after being poisoned, as the insulin overdose starved his brain of oxygen.
Chua was found not guilty of the murder of 71-year-old Arnold Lancaster but convicted of poisoning him in an act the judge described as "indescribably wicked".
In all, Chua was convicted of two murders, 22 counts of attempted grievous bodily harm, one count of grievous bodily harm, seven attempts of administering poison and one count of administering poison.
He received 25 life sentences in total and showed no emotion as he was taken down to the cells. Judge Openshaw said he would be 84 years old before he was eligible for parole.
Chua's letter
A handwritten letter, described as the "bitter nurse confession", was found in Chua's kitchen
Among the evidence produced by the prosecution was a self-penned letter found at Chua's home, in Stockport, after his arrest in January 2012 for changing prescription charts so patients would get dangerously incorrect amounts of drugs.
In the letter, described as "the bitter nurse confession" by Chua, he said he was "an angel turned into an evil person" and "there's a devil in me". He also wrote of having things he would "take to the grave".
Det Supt Simon Barraclough, who led the investigation for Greater Manchester Police, said Chua failed to show "any form of remorse" throughout the investigation and trial.
Even when being sentenced "there was not a flicker of emotion on his face, apart from what appeared to be just a general contempt for all the proceedings", he added.
'Great distress'
Investigations by police found inconsistencies in Chua's medical qualifications, which they raised with the Department of Health and the Home Office, as well as contacting the Nursing and Midwifery Council (NMC).
Concerns were also raised by a BBC investigation which revealed that fake nursing degrees were being sold in the Philippines for £20.
Nazir Afzal, who was responsible for prosecuting Chua, said the Stepping Hill case raised the "extremely worrying" prospect that many untrained foreign workers could be working in UK hospitals.
However, the NMC said a review of nurses who trained outside the European economic area - including 11,500 Filipino records - found just four with fraudulent qualifications in the last 10 years.
Chief executive Jackie Smith, said: "We checked every single record - I think that was a proportionate response to this one-off but very tragic and very serious event."
She said not all the records of other overseas countries had been checked, adding: "We took advice on what would be a sample of a review across the register that would give us confidence.
"There is no such thing as a fool-proof system - we are not a fraud agency - but do we have a system in place that doesn't just rely on documentation."
In a statement, Stockport NHS Foundation Trust said: "Our thoughts have been with the victims and their families throughout this time.
"We know they have suffered great distress but hope this sentence helps provide some closure for them in terms of seeing that justice has been served."

let down by poor end-of-life care

Thousands of dying patients are being let down by poor end-of-life care provision, the organisation that makes final decisions about NHS complaints in England has said.

The health ombudsman's report detailed "tragic" cases where people's suffering could have been avoided or lessened.

In one instance, a patient had suffered 14 painful attempts to have a drip reinserted during his final hours.

The government said improving end-of-life care was a priority.

The Parliamentary and Health Service Ombudsman has investigated 265 complaints about end-of-life care in the past four years, upholding just over half of them.

Catalogue of failings

Its Dying Without Dignity report said it had found too many instances of poor communication, along with poor pain management and inadequate out-of-hours services.

One mother told the ombudsman how she had had to call an A&E doctor to come and give her son more pain relief because staff on the palliative care ward he had been on had failed to respond to their requests.

In another case, a 67-year-old man's family learned of his terminal cancer diagnosis through a hospital note - before he knew himself. This "failed every principle of established good practice in breaking bad news", the report said.

"There was an avoidable delay in making a diagnosis," it added. "An earlier diagnosis would have meant opportunities for better palliative care."

Ombudsman Julie Mellor told Radio 4's Today the report made "very harrowing reading".

She also urged the NHS to learn lessons from the report, adding: "Our casework shows that too many people are dying without dignity.

"Our investigations have found that patients have spent their last days in unnecessary pain, people have wrongly been denied their wish to die at home, and that poor communication between NHS staff and families has meant that people were unable to say goodbye to their loved ones."

'Appalling cases'

Macmillan Cancer Support chief executive Lynda Thomas said: "The report cites heartbreaking examples of a lack of choice at the end of life that are totally unacceptable.

"If we are to improve the current situation, we will have to see a dramatic improvement in co-ordination of care, and greater integration of health and social care."

The chief inspector of hospitals at the Care Quality Commission, Prof Sir Mike Richards, said the organisation had seen examples of excellent end-of-life care, but also instances where it had not been given enough priority.

He said the CQC would continue to highlight those services that were failing.

A Department of Health spokesman said: "These are appalling cases - everyone deserves good quality care at the end of their lives.

"The five priorities for end-of-life care we brought in emphasise that doctors and nurses must involve patients and their families in decisions about their care, regularly review their treatment and share patients' choices to make sure their wishes are respected.

"NHS England is working on making these priorities a reality for everyone who needs end-of-life care."

Lower back pain

Lower back pain linked to chimpanzee spine shape

Chimpanzees are our closest primate relatives

People with lower back problems are more likely to have a spine similar in shape to the chimpanzee, our closest ape ancestor.

A lesion which forms in the disc between the bones of the spine is the reason for the differing shape.

It would have caused the vertebrae to change as humans evolved from using four legs to two legs.

The researchers say their findings could help doctors predict who may be at risk of back problems.

The study, published in BMC Evolutionary Biology, involved scientists from Scotland, Canada and Iceland.

The research team analysed the vertebrae of chimpanzees, orangutans and ancient human skeletons to investigate the relationship between the shapes of the bones of the spine, upright movement and the health of the human spine.

Prof Mark Collard, from the University of Aberdeen and Simon Fraser University in Canada, said they provided valuable insights into our ancestors' health and lifestyles.

Back pain is a very common health issue in humans

The skeletons also provided information about how humans evolved to move on two "rear" legs.

"Our findings show that the vertebrae of humans with disc problems are closer in shape to those of our closest ape relatives, the chimpanzee, than are the vertebrae of humans without disc problems."

The research picked up that these individuals have a lesion called a Schmorl's node - a small hernia which can occur in the disc between the vertebrae.

Although there is not one cause for the node, it is thought to be linked to stress and strain on the lower back.

Evolution is not perfect, so over many thousands of years humans have not all adapted in the same way.

Prof Collard said: "Our study suggests that the pathological vertebrae of some people may be less well adapted for walking upright."

They say their findings could have benefits for modern health issues and be used as a predictive tool.

Speaking exclusively to the BBC, Dr Peter Wilson, paediatric intensive care consultant at Southampton General Hospital,

Ashya King: Southampton hospital staff criticise parents

By David FentonHealth correspondent, BBC South Today10 April 2015

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Media captionAshya King was taken out of hospital by his parents to receive proton beam therapy abroad

Doctors and nurses who treated cancer patient Ashya King have criticised his parents while speaking out for the first time in a BBC documentary.

Ashya was being treated in hospital in Southampton when his parents took him abroad without telling staff last year.

They ignored medical advice and took him to Prague for proton beam therapy.

It was later revealed Ashya did not receive subsequent chemotherapy in Prague, a move the team in Southampton say could jeopardise his recovery.

Speaking exclusively to the BBC, Dr Peter Wilson, paediatric intensive care consultant at Southampton General Hospital, said: "We are unsure as to exactly what treatment he is receiving but what we do know is... every month that goes by that he's not getting chemotherapy, his outcome worsens.

Dr Peter Wilson and other members of the medical team received hate mail

"There are experts in the country that have already quoted figures of halving survival - so survival going from 80% to 40% or 50%, which is quite dramatic."

The Kings' version of events last year sparked a public outcry and staff members in Southampton said they received angry emails, letters and phone calls which, at one stage, forced the hospital to shut its switchboard.

The King family, who in March said five-year-old Ashya was now cancer free, declined to be interviewed as part of the BBC programme.

Has Ashya been cured?

In March, four months after the proton treatment ended, Brett King told a national newspaper a recent scan showed "no evidence" of the tumour.

But cancer experts have told the BBC although it appears Ashya is in remission it is far too early to say he has been completely cured.

Oncology specialist Professor Karol Sikora said: "Ashya is not completely out of the woods yet, but 78% of children with this type of rare cancer actually survive and are cured.

"The fact he is disease free at this point is great, but it doesn't mean he is cured yet."

The breakdown in the relationship between Brett King and the hospital stemmed from his belief that Ashya should not receive radiotherapy and chemotherapy following surgery to remove a brain tumour.

Mr King claimed in a YouTube video that staff threatened him with a court order if he refused Ashya's treatment, something the hospital has denied.

He told journalists in Spain after his arrest: "They were going to kill him in England or turn him into a vegetable."

Brett King made accusations against the hospital in a YouTube video

Key events

• Ashya had surgery for a medulloblastoma brain tumour at Southampton General Hospital in July 2014
• His parents, Brett and Naghemeh, removed him from the hospital on 28 August and sparked a manhunt when they travelled to Spain
• They were arrested but later released and Ashya was flown to Prague, Czech Republic, for proton beam treatment
• He had six weeks of proton beam therapy, which cost between £60,000 and £65,000, according to the treatment centre, and was paid for by the NHS
• Ashya returned to hospital in Spain
• In March, Brett King announced his son was free of cancer

Through the media, the King family raised tens of thousands of pounds for Ashya's treatment before the NHS agreed to pay for proton therapy in Prague.

Dr Nicky Thorp, of the Children's Cancer and Leukaemia Group of paediatricians, said: "We were dismayed, but on reflection I can see why NHS England agreed to fund that child's case. The child was there, the child needed radiotherapy.

"The use of protons does not improve cure rates of tumours... and it saddens me to see the way the truth can be twisted and misunderstood."

Southampton General Hospital received abuse on social media

In Prague, Ashya's parents refused the chemotherapy, which had been recommended by doctors and ordered by the High Court.

But in March, four months after the proton treatment ended, Mr King said his son was cancer free.

Paediatric oncology consultant Dr Ramya Ramanujachar, who was involved in Ashya's treatment, warned the case could set a worrying precedent.

Dr Ramya Ramanujachar accused the Kings of "dictating" their son's treatment

She said: "I don't think the parents can look after their own child with a brain tumour and be not only the carers but also the professionals directing, managing and dictating their child's treatment."

Dr Wilson said the case had led to an "impossible situation" for clinicians faced with families in the same situation.

"That is deeply unfair when the NHS is always supposed to be about equal healthcare for all," he added.

Ashya: The Untold Story is to be broadcast on BBC1 in the South region on Friday at 19:30 BST.

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Care system gets 'biggest shake-up in 60 years'

 England are being introduced in what is being dubbed the biggest shake-up for 60 years.

The Care Act 2014 includes rights for those receiving care and those who provide it to their loved ones.

It includes standards for access to services from care homes to help in the home for tasks such as washing and dressing.

Meanwhile, NHS and care budgets are being merged in Scotland.

The Public Bodies (Joint Working) Act has been described as the most substantial reform north of the border for a generation.

It effectively forces councils and the NHS to work together to provide more streamlined services.

That aim is also a major topic of debate in England in the election campaign with the Conservatives, Labour, Liberal Democrats, UKIP and Greens all having plans for greater integration.

Policy guide: Health and care

This issue includes NHS funding, GP access and social care, particularly of older people.

Compare parties' policies

But the changes coming into force in England on Wednesday apply only to the care system for older people and younger adults with disabilities.

Four major changes are being introduced:

• The creation of national eligibility criteria establishing for the first time when someone should be entitled to help - to date, it has been up to councils to set their own criteria
• A duty on councils to offer schemes by which those who need to pay for residential care can get a loan from their local council, which is then paid back from their estate after death
• Giving carers for the first time the same right to assessment and support as the people they care for; before, they had to provide "substantial care on a regular basis" to get an assessment
• Those who pay for care themselves will be entitled to go to councils to get advice and information about the care system.

To help protect people's assets, a cap on care costs they have to pay for - set at £72,000 for the over-65s - will kick in from April next year. How the cap works for younger people has still to be finalised.

Today's changes, however, still mark a major milestone in care services, which experts say have hardly changed since the current system was created along with the NHS after the Second World War.

BBC Cost of Care project

The BBC has launched an online guide to the care system for the over-65s. The "care calculator" covers residential care and the support provided in people's own homes, for tasks such as washing and dressing.

Users can submit their postcode and find out how much each service costs where they live in the UK.

There is also a dedicated BBC Cost of Care website, with news stories, analysis and video.

• The care calculator
• Cost of Care website
• How the systems differ in the UK
• England's care cap explained

David Pearson, president of the Association of Directors of Adult Social Services, said the changes were "probably the most significant development" since 1948.

But he said there were still issues to resolve on the underfunding of the system. Unlike the NHS, the care system budget has been cut in real terms this Parliament.

Izzi Seccombe, leader of Warwickshire council, who chairs the Local Government Association's Wellbeing Board, agreed with both points.

"Councils simply cannot afford any more financial burdens when social care services are already chronically underfunded," she said.

Janet Morrison, of the charity Independent Age, said the Care Act had the "potential to revolutionise" services.

But she said: "With a rapidly ageing population, we need an honest debate during and after the election about the true costs of care."

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