Thursday, 23 September 2010

Cerebral malaria may have passed

22 September 2010 Last updated at 18:13

Cerebral malaria may have passed from gorillas to us

By Katie Alcock Science reporter, BBC News

Gorillas may be the source of human cerebral malaria

Humans may have originally caught malaria from gorillas, scientists say.

Until now, it was thought that the human malaria parasite split off from a chimpanzee parasite when humans and chimpanzees last had a common ancestor.

But researchers from the US, three African countries, and Europe have examined malaria parasites in great ape faeces.

They found the DNA from western gorilla parasites was the most similar to human parasites.

Cerebral malaria

Malaria is caused by a parasite called Plasmodium, and is carried by mosquitoes.

The most common species found in Africa, Plasmodium falciparum, causes dangerous cerebral malaria. Over 800,000 people die from malaria each year in the continent.

Until now, scientists had assumed that when the evolutionary tree of humans split off from that of chimpanzees - around five to seven million years ago - so had Plasmodium falciparum.

This would have meant that humans and malaria co-evolved to live together. But new evidence suggests human malaria is much newer.

Dr Beatrice Hahn of the University of Birmingham, Alabama, in the US, is part of a team that had been studying HIV and related infections in humans and great apes.

Cerebral malaria kills nearly a million people in Africa every year

DNA analysis

To study the DNA of infections in wild apes, you cannot use blood samples. So the team collected 2,700 samples of faecal material from two species of gorilla - western and eastern - and from common chimpanzees and bonobos, also known as pygmy chimpanzees.

They tried sequencing Plasmodium DNA from the faeces with techniques that use a large sample, and drew a genetic family tree to see which parasites were related. Dr Hahn said "When we did conventional sequencing, the tree didn't make any sense, because each sample contained a mixture of parasites."

They diluted the DNA so that they had just one parasite's genome represented in a single sample, and then amplified the DNA from there. This means they were able to separate the DNA from different species of the parasite much more effectively.

They then found the tree made much more sense. But they also found some surprising results.

The human Plasmodium was not very closely related to chimpanzee Plasmodium, as had been thought - but it was very closely related to one out of three species of gorilla Plasmodium from western gorillas in Central and West Africa.

There was more genetic variety in the gorilla parasites than in human parasites, and Dr Hahn said this means the gorilla is likely to be the "reservoir" - the origin of the human parasite.

"Other studies have just looked at chimps, so didn't find the gorilla parasite," said Dr Hahn. She added that some studies have looked at animals in captivity - so it is possible any parasites have "jumped" from their human keepers.

“Start Quote

Other studies have just looked at chimps, so didn't find the gorilla parasite”

End Quote Dr Beatrice Hahn University of Birmingham, Alabama, US

Cross-infection

The researchers, who report their findings in Nature, are now going to investigate further to see exactly how different the gorilla and human parasites are. Dr Hahn says that it is possible they are even the same species, and that cross-infection between humans and gorillas may be going on now.

Members of the team Dr Martine Peeters and Dr Eric Delaporte of the University of Montpelier in France are working with hunters and loggers in Cameroon, who spend a lot of time in the forests.

They will investigate whether these workers carry malaria parasites from the gorillas, which would suggest that new infections from other species can still happen.

They also do not yet know how badly apes are affected by malaria. Dr Hahn said that the team would now like to find out whether apes are able to catch the malaria parasite, without getting ill or dying in the way that humans do.

Monday, 20 September 2010

warning over vitamin D levels

19 September 2010 Last updated at 01:02

Scottish warning over vitamin D levels

Sunlight on the skin helps generate vitamin D

New leaflets are to be handed out urging people to make sure they get enough vitamin D.

Doctors are concerned people in Scotland are not getting enough of the vitamin from sunlight and are not topping up their levels with a healthy diet.

There is increasing evidence that a lack of vitamin D could be linked to cancer and multiple sclerosis.

Doctors are also concerned about a rise in the bone disease rickets.

Rickets is a rare condition which causes the softening and weakening of bones in children.

Pregnant and breastfeeding women are particularly at risk of vitamin D deficiency, along with children under five, the elderly, the housebound and people with darker skin.

About 10 to 15 minutes a day of sunshine is considered safe.

Analysis

Eleanor Bradford BBC Scotland Health Correspondent

Although the advice in these leaflets isn't new, the Scottish NHS is the only health service in Britain highlighting the dangers of vitamin D deficiency.

If you live in Scotland you'll be familiar enough with the Scottish weather to know why!

On the one hand we're always being warned about the dangers of too much sunshine, now we're being told we're not getting enough.

It's an easy balance to strike though - 10-15 minutes a day is safe and avoid the middle of the day when the sun's rays just burn you.

But in Scotland the sun is only strong enough to provide vitamin D between April and September.

If the body's reserves of vitamin D run out during the winter, they need to be topped up from oily fish, eggs, meat or a supplement.

Health Secretary Nicola Sturgeon said: "We know that in Scotland the winter sun is not strong enough to provide the minimum vitamin D needed for health - especially for those with darker skin.

"A significant proportion of the UK population has low vitamin D levels. This leaflet aims to ensure that those at risk are aware of the implications of vitamin D deficiency and know what they can do to prevent it."

She added: "Vitamin D is key to maintaining healthy bones. Young children have a high risk of deficiency and we are seeing an increase in reported cases of rickets in Scotland.

"These conditions are easily prevented by improving diet and taking a supplement if you are at risk.

"Recent research suggests that vitamin D deficiency may also contribute to a range of other medical conditions. The Scottish government are keen to continue to monitor this evidence."

The health secretary is due to speak at the Shine on Scotland conference on Tuesday, which will bring together academics from across the world to consider the possible links between vitamin D deficiency and various health problems.

The event is taking place after schoolboy Ryan McLaughlin took a petition to the Scottish Parliament which called on ministers to produce new guidelines on vitamin D supplements for children and pregnant women, along with an awareness campaign about the issue.

Ryan took up the cause after watching his mother Kirsten suffering from MS.

He said: "It's amazing that I only launched Shine on Scotland early last year and so much has happened since.

"The petition lodged at the Scottish Parliament got great support and I'm really grateful to the Scottish government for being prepared to look at this issue.

"I hope the summit is a great success and that something positive can be done for people with MS and to prevent future generations from developing it."

Wednesday, 15 September 2010

Pope adviser calls the UK a 'Third World country'

The Vatican said the cardinal was pulling out of the visit solely on health grounds

One of the Pope's senior advisers has pulled out of the papal visit to Britain, after reportedly saying the UK is a "Third World country" marked by "a new and aggressive atheism".

Cardinal Walter Kasper, 77, made the remarks in a German magazine interview.
The Vatican said the cardinal had not intended "any kind of slight", and was referring to the UK's multicultural society.
It added that he had simply pulled out of the Pope's visit due to illness.

They are saying it is ill health, but I wonder if that is the fact. I wonder if he has been dropped because he is an embarrassment”

End Quote Clifford Langley The Tablet

The German-born cardinal was quoted as saying to the country's Focus magazine that "when you land at Heathrow you think at times you have landed in a Third World country".

He also was reported to have criticised British Airways, saying that when you wear a cross on the airline "you are discriminated against".
Vatican sources said Cardinal Kasper - who stepped down in July as the head of the department that deals with other Christian denominations - was suffering from gout and had been advised by his doctors not to travel to the UK.
The Pope is spending four days in Scotland and England, starting on Thursday.
'Talking nonsense'
The BBC's correspondent in Rome, David Willey, said the cardinal's reported comments were "a slightly clumsy thing to have done on the eve of the visit".
However, he added that he did not think it would have much effect on the Pope's trip to the UK.
Clifford Langley, from Catholic newspaper The Tablet, said the cardinal was "obviously talking nonsense".
"I don't think he believes Britain is in the grip of secular atheism, and he shouldn't have said so," said Mr Langley.
"They are saying it is ill health [that has forced the cardinal to drop out of the visit], but I wonder if that is the fact. I wonder if he has been dropped because he is an embarrassment."
British Airways said the cardinal had been "seriously misinformed" in his claims about the airline.
"It is completely untrue that we discriminate against Christians or members of any faith," it said in a statement.

Tuesday, 14 September 2010

schools using special needs too widely

14 September 2010 Last updated at 10:30

Ofsted says schools using special needs too widely

By Heather Sharp Education reporter, BBC News

Some schools were failing to spot pupils' needs early enough

Thousands of pupils are being wrongly labelled as having special educational needs when all they require is better teaching and support, Ofsted has said.

It said up to 25% of the 1.7m pupils in England with special needs would not be so labelled if schools focused more on teaching for all their children.

The education standards watchdog said the term "special needs" was being used too widely.

The National Union of Teachers said such claims were "insulting and wrong".

More than a fifth of school-age students in England have been identified as having some form of special educational needs (SEN), which range from physical disabilities to emotional and behavioural problems.

The wide-ranging study was Ofsted's biggest yet into a system that some parents have complained draws them into long and difficult battles to secure effective support for their children.

Click to play

Christine Grainger says her son Dean could not get the specialist teaching he needed

Inspectors visited 228 nurseries, schools and colleges in 22 local authorities, and carried out detailed case studies of 345 young people with disabilities and special educational needs.

Ofsted chief inspector Christine Gilbert said: "Although we saw some excellent support for children with special educational needs, and a huge investment of resources, overall there needs to be a shift in direction."

Ms Gilbert told BBC Radio 4's Today programme: "We felt that schools and teachers were well intentioned but they were over-diagnosing the problems - teachers in the classroom weren't confident they could deal with the problems.

"We feel teachers and schools need to have more confidence themselves about looking at what are barriers to learning."

Some 54% of students with SEN - those with the least severe problems - are assessed by their schools, while the 2.7% with the most acute difficulties go through a complex process of assessment under their local authority to obtain a "statement" of their needs.

Ofsted's inspectors said the term SEN was used too widely and assessments varied widely in different areas.

“Start Quote

There is a real problem, if your class is big - 30 or 30+ children - then finding the time to give an individual child the attention they need is not easy”

End Quote Kevin Courtney National Union of Teachers

Send us your comments

They said schools should "stop identifying pupils as having SEN when they simply needed better teaching and pastoral support".

As many as half of all pupils identified for school action "would not be identified as having SEN if schools focused on teaching and learning for all", the report said.

The report's author, Janet Thompson, said these cases included children whose general educational needs had not been identified early enough - such as children who struggled with reading and later developed behavioural difficulties as a result.

But, she said, there were also cases where schools had labelled students as having SEN - such as GCSE students becoming demotivated - when they just needed better support.

'Clogged system'

The report said the system focused too much on statements of need and not enough on whether support services were actually producing real progress.

It also highlighted problems faced by students aged over 16 with SEN, for whom it said choice was limited.

Ofsted said some schools had been over-identifying students with SEN in the belief that increased figures would boost league table scores on the progress pupils made, but there was no evidence this was a system-wide problem.

While extra funding available in some areas for children with SEN offered an "obvious motivation" for schools to over-diagnose children, inspectors did not find evidence that this was taking place.

Ms Gilbert said that if SEN cases were over-identified, "the system becomes clogged" with pupils with less severe needs and "consumes vast amounts of time, energy, money and means that insufficient attention may be given to those with really more complex needs".

The National Union of Teachers, the largest teachers' union, said the report's findings were "insulting and wrong"

Deputy general secretary Kevin Courtney told the BBC the report overlooked the pressures on teachers, and was "softening up the public for cuts to SEN budgets".

"There is a real problem, if your class is big - 30 or 30+ children - then finding the time to give an individual child the attention they need is not easy," he said.

The second biggest teachers' union, the NASUWT, said it was "unacceptable to scapegoat teachers" for the variability in identifying and supporting children with SEN.

And the Association of Teachers and Lecturers said the report had overlooked factors such as school league tables "which put pressure on schools to narrow their curriculum and teach to the test", and teacher training, "which ill-prepares teachers for working with children with SEN and disabilities".

Inclusion policy

Children's Minister Sarah Teather is calling for submissions for a Green Paper on overhauling SEN provision.

"Ofsted said the system at the moment isn't working and I think they're right," she told the BBC.

She said many parents felt they needed to battle the system to get the support their children needed.

However, the coalition's proposed "pupil premium" will target extra money at children from disadvantaged backgrounds, and should give schools more flexibility to offer more one-to-one support, she added.

The Labour government tried, under a policy of "inclusion", to place pupils with special educational needs in mainstream schools wherever possible.

The Conservative-Liberal Democrat government says, in its coalition agreement, that it will "prevent the unnecessary closure of special schools, and remove the bias towards inclusion".

The number of state and private special schools in England has fallen from 1,197 in 2000 to 1,054 in 2010.

Does your child have special needs? Or do you think your child has been wrongly identified as requiring special needs? Are you a teacher? What do you think about the report? You can send us your views and experiences using the form below.

It is in the interest both of teachers and parents to arrange for as many children as possible to be assessed with "special needs". Parents work the system by arranging for a private assessor to assess their normal child as in "special need". The child then is given an extra 25% of time in examinations and other extra help at school. The extra time and help can make the difference between an "A" and a lower grade.

Angus Palmer, Godalming

Is anyone asking how many people reach school leaving age who were not statemented but should have. We experience a number of such cases per year. Often these are the children of the least able or articulate parents who have been unable to fully represent the interests of their child. Even people with autism can remain undiagnosed. OFSTED should have given more consideration to this.

Danny, Croydon

Our son was put on the school's special needs list to the shock of ourselves and other parents. It turns out that his teacher was regularly putting boys on the register because she couldn't cope very well with the antics of 5 year old boys. It took us over a year to get him off the list, despite his subsequent teacher saying that he clearly exhibited no signs of special needs.

Monday, 13 September 2010

EU tightens rules on welfare of lab animals

8 September 2010 Last updated at 14:57

EU tightens rules on welfare of lab animals

Click to play

MEPs approved new rules on animal welfare in lab experiments

The EU has agreed on new rules aimed at reducing the number of animals used in lab experiments and tightening controls over such procedures.

Euro MPs backed the new EU directive after long negotiations and EU member states have two years to make it law.

Labs will have to get approval from national authorities for animal tests and if recognised alternatives exist then they must be used, the rules say.

Animal welfare groups say the directive still does not go far enough.

The UK-based anti-vivisection group BUAV called it "a missed opportunity".

"The dropped proposals include strong restrictions on the use of non-human primates, strong restrictions on re-using individual animals, and a clear ban on experiments which involve severe and prolonged suffering," it said.

But BUAV said it was "pleased, however, that the [European] Commission has clarified that non-animal alternatives have to be used wherever they are scientifically suitable".

The new directive, approved by the European Parliament on Wednesday, replaces EU rules on animal testing that dated back to 1986.

The new animal welfare standards will have to be embraced by all EU member states

Now the new member states - mainly in Central and Eastern Europe - that joined the EU in 2004 and 2007, will have to embrace the new animal welfare standards.

The legislation imposes a general ban on the use of great apes, such as chimpanzees and gorillas, in scientific tests. But other primates such as macaques can still be used - a point on which the Commission was overruled by MEPs.

Measuring pain

The directive also sets out categories of pain, ranging from "mild" to "severe" - an innovation designed to prevent repeated suffering.

The re-use of animals will be allowed after tests involving "moderate" pain - though the Commission had proposed re-use only after tests classed as "up to mild" pain.

MEPs argued that re-use of animals helped reduce the total number of animals used. They were also concerned that Europe should not fall behind in research on chronic human ailments such as Alzheimer's.

According to EU data, about 12 million animals are used in EU countries' lab experiments each year.

The directive obliges national authorities to carry out regular inspections of labs that use animals - and some of the visits must be unannounced. The Commission will oversee these checks.

The animal protection group Humane Society International said the new directive would still not prevent "severe suffering" in certain types of animal testing.

But it voiced hope that other countries, including the US, would now "follow Europe's lead so that standards are improved globally".

Botox industry register launched

13 September 2010 Last updated at 00:17

Botox industry register launched

By Neil Bowdler Health reporter, BBC News

Click to play

Former beauty clinic manager Sarah Payne recalls how a dermal filler treatment went badly wrong

A government-backed register for providers of injectable cosmetic treatments such as botox and dermal fillers has been launched.

Those who meet the standards set down for the Independent Heathcare Advisory Services' voluntary register, will receive a quality assurance mark.

The IHAS hopes people will be steered away from "botox parties" or treatments offered in inappropriate locations.

But cosmetic surgeons say such self regulation will not stop bad practice.

Botox boom

The introduction of the register comes amid a boom in demand for botox and dermal fillers.

According to the IHAS, there are currently about 5,000 providers of injectables in the UK, carrying out about 200,000 treatments each year.

Other estimates suggest far higher numbers of people in the UK are seeking out these treatments.

“Start Quote

Self-regulation hasn't worked in the Houses of Parliament has it, and it hasn't worked in the banking industry, so why would it work in cosmetic medicine?”

End Quote Nigel Mercer British Association of Aesthetic Plastic Surgeons

But there are growing concerns over people receiving treatments in inappropriate settings.

"We've heard stories of botox parties and people going to even garden sheds [to have treatment], " IHAS director Sally Taber said.

"It's just amazing that the general public think that they can have an injection into their face in a nail bar, a garden shed or at a botox party, because you are dealing with a prescription medicine.

"They can cause permanent damage. The patient will be reminded all their lives that they've gone to an inappropriate practitioner who wasn't appropriately qualified," she warns.

No beauticians

The new register of injectable cosmetic providers represents an attempt by the injectables industry to regulate itself.

It will be funded by the treatment providers who must pay registration and annual fees to join.

Those signing up to the register must promise that all prospective clients receive a face-face consultation before any treatment goes ahead.

They must also ensure that procedures takes place in a clean and safe clinical setting and registered premises may be inspected at random by an outside agency.

Those injecting must also have the right training, with only doctors, dentists and registered nurses eligible.

INJECTABLE

Botox is a trade name for a protein produced by the bacterium Clostridium botulinum and is highly toxic
In small doses, Botox works by temporarily paralysing the muscles of the face which are used in frowning and raising the eyebrows
In larger doses, Botox can leave the face with a lack of expression
Dermal fillers are usually used in the lower face to "fill" in wrinkle lines and folds and to pump up cheeks and lips
Non-permanent dermal fillers include bovine (cow) collagen and products based on hyaluronic acid
Other injectable gels such as Macrolane are used to augment breasts and buttocks

"Occasionally a patient could have an anaphylactic shock when the patient has a reaction to the medicine and collapses and may need a tube down their throat to ensure their airway is sufficient for them to breath again," Ms Taber said.

"We don't feel that it is appropriate for a beauty therapist to have that kind of responsibility."

The new scheme has already come under heavy criticism from plastic surgeons. A recent poll among members of the British Association of Aesthetic Plastic Surgeons found only 4% would consider signing up.

The organisation's outgoing president Nigel Mercer says the scheme is more about clinics marketing their services than protecting the consumer.

"Self-regulation hasn't worked in the Houses of Parliament has it, and it hasn't worked in the banking industry, so why would it work in cosmetic medicine?" he said.

"Self-regulation effectively means it's a free for all.

"What we've been suggesting is something like 'Ofcos'. Obviously quangos are not the order of the day at the moment, but there really is public harm being done."

He also points to new European regulations that are currently under consideration, which he says, offer a more robust alternative.

Ms Taber believes such is the cost-cutting climate of the moment, that external regulation is off the agenda.

"All of the industry wanted regulation to begin with," she said, "but it's obvious from the previous government and now the coalition government, that has given this scheme its support, that we're not going to get it.

"A set of professionally led standards at the moment is the correct way forward."

Trout pout

Botox works by temporarily paralysing nerves in the upper face to reduce wrinkling when people smile or frown.

Dermal fillers, such as hyaluronic acid, are used largely on the lower face to fill in creases and wrinkles. They can also be used to pump up cheeks and produce a lip "pout".

Some of these fillers offer temporary solutions, others are semi-permanent or permanent.

But while many are turning to these treatments, there are undoubted risks.

Michael Saul of Manchester-based solicitors TJL specialises in representing victims of substandard cosmetic surgery and injectable treatments.

"You find a whole raft of problems following these treatments. There's asymmetry if they are not injected correctly, you can have lumps and nodules which look extremely unsightly in prominent areas of the face. There are problems with infection and terrible allergic reactions."

He also has a case where the injected product migrated under the skin.

"The dermal filler has migrated from the nasolabial fold into the eye orbit and is causing problems with vision. It's going to be very difficult and dangerous to remove it from the eye orbit and it carries a risk of blindness."

He too favours external regulation. "This industry is very profitable for practitioners and inadequately regulated and that's a very dangerous mix," he said.

He believes those who speak out or seek out legal representation represent only "the tip of the iceberg".

"A lot of people don't know where to run if they have problems so don't do anything. If something goes wrong after an aesthetic procedure, a common psychological reaction for people is to blame themselves. A lot of people want to lock themselves away."

Friday, 10 September 2010

Halley's comet 'was spotted by the ancient Greeks'

Halley's comet may have been visible from Earth in 466BC, say the researchers

A celestial event seen by the ancient Greeks may be the earliest sighting of Halley's comet, new evidence suggests.

According to ancient writers, a large meteorite smacked into northern Greece between 466BC and 467BC.

The writers also described a comet in the sky at the time the meteorite fell to Earth, but this detail has received little attention, say the researchers.
Comet Halley would have been visible for about 80 days in 466BC, researchers write in the Journal of Cosmology.

New Scientist magazine reports that, until now, the earliest probable sighting of the comet was an orbit in 240BC, an event recorded by Chinese astronomers.

If the new findings are confirmed, the researchers will have pushed back the date of the first observation of Comet Halley by 226 years.
The latest idea is based on accounts by ancient authors and concerns a meteorite that is said to have landed in the Hellespont region of northern Greece in 466-467BC.
The space rock fell during daylight hours and was about the size of "a wagon load", according to ancient sources.
The object, described as having a "burnt colour", became a tourist attraction for more than 500 years.
Look west
In his work Meteorology, Aristotle wrote about the event about a century after it occurred. He said that around the same time the meteorite fell, "a comet was visible in the west".
Astronomer Eric Hintz and philosopher Daniel Graham, both of Brigham Young University in Provo, Utah, reconstructed the likely path of Halley's comet, to see whether it agreed with the ancient observations.
They calculated that Halley's comet could have been visible for about 80 days between early June and late August in 466BC - depending on atmospheric conditions and the darkness of the sky.
"It's tough going back that far in time. It's not like an eclipse, which is really predictable," co-author Eric Hintz, from Brigham Young University in Provo, Utah, told BBC News.
"But we feel fairly good about this. If the [sighting] in 240BC is accepted, this has a fairly solid possibility."
He added: "If accepted, this would be three orbits earlier [than the Chinese sighting]."

Halley's Comet on the Bayeux Tapestry (Getty)

In the 11th Century, Halley's Comet was depicted on the Bayeux Tapestry

The reconstruction of the comet's path agrees with the ancient reports, which say the comet was visible for about 75 days.
The researchers point out that while the Chinese and Babylonians kept meticulous records of heavenly phenomena for centuries, the ancient Greeks did not.
Nevertheless, the Greek accounts do provide important information, say Graham and Hintz, such as the comet's period of visibility from Earth.
Asked whether it was possible that the meteorite fall and the pass by Halley's Comet could be linked, Dr Hintz was doubtful.
"it would be really neat if they were connected - if it was a piece of Halley's that fell. My feeling is that it was just a really cool coincidence," said Dr Hintz.
The researchers say that there remains the possibility that other ancient sightings of comets could be uncovered from Chinese and Babylonian records.

Thursday, 9 September 2010

Astronomers find evidence for unusual class of black holes

An artist's impression of the source HLX-1 - the light blue object to the top left of the galactic bulge

Researchers say they may have found further evidence for the existence of an unusual type of black hole.

Using the European Southern Observatory's Very Large Telescope (VLT) in Chile, an international team of scientists studied the images of the most extreme ultra-luminous X-ray source, HLX-1.

An artist's impression of the source HLX-1

They say the data about the distance and the brightness of the source shows that it may contain an intermediate-size mass black hole, located some 300 million light years away from Earth.
The results of the study have been published in the Astrophysical Journal.
A black hole is a region of space that has such an extremely powerful gravitational field that it absorbs all the light that passes near it and reflects none.
If confirmed, HLX-1 would be classified as an intermediate-type black hole - something astrophysicists suspected to exist, but for which there have been only tentative detections in the past.
Radiation question
The lead author Klaas Wiersema of the University of Leicester's department of Physics and Astronomy, said that after the earlier discovery of the very bright X-ray source, the astronomers "were very keen to find out just how far away it really is, so that we can work out how much radiation this black hole produces".

Understanding how super-massive black holes form... is crucial to our comprehension of the formation of galaxies”

End Quote Sean Farrell University of Leicester

"We could see on images taken with big telescopes that a faint optical source was present at the location of the X-ray source, located near the core of a large and bright galaxy," he said.

"We suspected that this faint optical source was directly associated with the X-ray source, but to be sure we had to study the light of this source in detail, using the Very Large Telescope in Chile."
He said that the VLT was able to measure the precise distance to HLX-1 and the data from the telescope allowed the scientists to separate the light of the big, bright galaxy from that of the faint optical source.
"Much to our delight we saw in the resulting measurements exactly what we were hoping for: the characteristic light of hydrogen atoms was detected allowing us to accurately measure the distance to this object.
"This provided conclusive proof that the black hole was indeed located inside the big, bright galaxy, and that HLX-1 is the brightest ultra-luminous X-ray source known."
Galactic centre
HLX-1 is located in another galaxy some 300 million light years from our planet. The study also shows that the source is not a super-massive black hole.

An artist's impression of a black hole at the centre of a galaxy

Astronomers believe that the centres of most galaxies contain such super-massive black holes, and intermediate black holes might simply turn out to be their progenitors.
"Understanding how super-massive black holes form and grow is thus crucial to our comprehension of the formation and evolution of galaxies, which in turn goes part of the way to answering one of the really big questions: how did our own galaxy form and evolve?" said astronomer Sean Farrell, also of the University of Leicester.

Astronomers find evidence for unusual class of black holes

9 September 2010 Last updated at 08:24

Astronomers find evidence for unusual class of black holes

By Katia Moskvitch Science reporter, BBC News

An artist's impression of the source HLX-1 - the light blue object to the top left of the galactic bulge

Researchers say they may have found further evidence for the existence of an unusual type of black hole.

Using the European Southern Observatory's Very Large Telescope (VLT) in Chile, an international team of scientists studied the images of the most extreme ultra-luminous X-ray source, HLX-1.

They say the data about the distance and the brightness of the source shows that it may contain an intermediate-size mass black hole, located some 300 million light years away from Earth.

The results of the study have been published in the Astrophysical Journal.

A black hole is a region of space that has such an extremely powerful gravitational field that it absorbs all the light that passes near it and reflects none.

If confirmed, HLX-1 would be classified as an intermediate-type black hole - something astrophysicists suspected to exist, but for which there have been only tentative detections in the past.

Radiation question

The lead author Klaas Wiersema of the University of Leicester's department of Physics and Astronomy, said that after the earlier discovery of the very bright X-ray source, the astronomers "were very keen to find out just how far away it really is, so that we can work out how much radiation this black hole produces".

“Start Quote

Understanding how super-massive black holes form... is crucial to our comprehension of the formation of galaxies”

End Quote Sean Farrell University of Leicester

"We could see on images taken with big telescopes that a faint optical source was present at the location of the X-ray source, located near the core of a large and bright galaxy," he said.

He said that the VLT was able to measure the precise distance to HLX-1 and the data from the telescope allowed the scientists to separate the light of the big, bright galaxy from that of the faint optical source.

"Much to our delight we saw in the resulting measurements exactly what we were hoping for: the characteristic light of hydrogen atoms was detected allowing us to accurately measure the distance to this object.

"This provided conclusive proof that the black hole was indeed located inside the big, bright galaxy, and that HLX-1 is the brightest ultra-luminous X-ray source known."

Galactic centre

HLX-1 is located in another galaxy some 300 million light years from our planet. The study also shows that the source is not a super-massive black hole.

An artist's impression of a black hole at the centre of a galaxy

Astronomers believe that the centres of most galaxies contain such super-massive black holes, and intermediate black holes might simply turn out to be their progenitors.

"Understanding how super-massive black holes form and grow is thus crucial to our comprehension of the formation and evolution of galaxies, which in turn goes part of the way to answering one of the really big questions: how did our own galaxy form and evolve?" said astronomer Sean Farrell, also of the University of Leicester.

Vitamin B 'puts off Alzheimer's'

8 September 2010 Last updated at 22:05

Vitamin B 'puts off Alzheimer's'

Brain scan of a person with Alzheimer's

A new study suggests high doses of B vitamins may halve the rate of brain shrinkage in older people experiencing some of the warning signs of Alzheimer's disease.

Brain shrinkage is one of the symptoms of mild cognitive impairment, which often leads to dementia.
Researchers say this could be the first step towards finding a way to delay the onset of Alzheimer's.
Experts said the findings were important but more research was needed.
The study, published in the journal Public Library of Science One, looked at 168 elderly people experiencing levels of mental decline known as mild cognitive impairment.
This condition, marked by mild memory lapses and language problems, is beyond what can be explained by normal ageing and can be a precursor to Alzheimer's and other forms of dementia.

Half of the volunteers were given a daily tablet containing levels of the B vitamins folate, B6 and B12 well above the recommended daily amount. The other half were given a placebo.

After two years, the rate at which their brains had shrunk was measured.
The average brain shrinks at a rate of 0.5% a year after the age of 60. The brains of those with mild cognitive impairment shrink twice as fast. Alzheimer's patients have brain shrinkage of 2.5% a year.
The team, from the Oxford Project to investigate Memory and Ageing (Optima), found that on average, in those taking vitamin supplements, brain shrinkage slowed by 30%.
In some cases it slowed by more than 50%, making their brain atrophy no worse than that of people without cognitive impairment.
'Protecting' the brain
Certain B vitamins - folic acid, vitamin B6 and B12 - control levels of a substance known as homocysteine in the blood. High levels of homocysteine are associated with faster brain shrinkage and Alzheimer's disease.

“Start Quote

These vitamins are doing something to the brain structure - they're protecting it, and that's very important because we need to protect the brain to prevent Alzheimer's”

End Quote Professor David Smith Oxford University

The study authors believe it was the B vitamins' effect on levels of homocysteine that helped slow the rate of brain shrinkage.

The study author, Professor David Smith, said the results were more significant than he had expected.
"It's a bigger effect than anyone could have predicted," he said, "and it's telling us something biological.
"These vitamins are doing something to the brain structure - they're protecting it, and that's very important because we need to protect the brain to prevent Alzheimer's."
He said more research was now needed to see whether high doses of B vitamins actually prevented the development of Alzheimer's in people with mild cognitive impairment.
The Alzheimer's Research Trust, which co-funded the study, also called for further investigation.
"These are very important results, with B vitamins now showing a prospect of protecting some people from Alzheimer's in old age," said chief executive Rebecca Wood.
"The strong findings must inspire an expanded trial to follow people expected to develop Alzheimer's."
B vitamins are found naturally in many foods, including meat, fish, eggs and green vegetables.
Experts are advising against taking higher than recommended levels in the light of these findings.
Chris Kennard, chair of the Medical Research Council's Neurosciences and Mental Health Board, said: "We must be cautious when recommending supplements like vitamin B as there are separate health risks if taken in too high doses.
"Further research is required before we can recommend the supplement as a treatment for neurodegenerative diseases, such as Alzheimer's."

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