Science News Digest - 23rd August 2010
In the science news this week, we find out how the number of kidney transplants in the UK could increase dramatically, learn how doctors can predict who is susceptible to TB, discover how a recent fossil find dates animal life much earlier than previously predicted, see how city bees may be healthier than their country cousins... and finally, learn about an ancient, terrifying, giant bird.
New hope for those awaiting transplant.
The UK has some of the lowest organ donation rates in Europe and the acute lack of kidneys available for transplant leads to approximately 700 deaths each year. There are about 7,000 people awaiting a new kidney on the transplant waiting list, but only 2,500 operations take place each year. A Cambridge University study has shown results that may double the number of UK kidney transplants in the future saving hundreds of lives a year.
The majority of transplanted UK kidneys come from "brain dead" deceased donors, who have suffered serious head trauma, usually as a result of a traffic or work related incident. The decrease in road related deaths has led to a decrease in the number of kidneys available for transplant.
The new study tested kidneys taken from donors who died as a result of heart failure following a head trauma. Previously it was thought that DCD (donated after cardiac death) kidneys were inferior to those who had died from head trauma only. The research showed that transplanted DCD kidneys were equally as good at extending life as non DCD kidneys.
The study assessed 9,134 patients who received transplanted kidneys in 23 different UK transplant centres between 2000 and 2007. 845 DCD kidneys were used along with 8,289 kidneys received after brain death. Both types were equally effective at keeping a patient alive for at least 5 years.
"Cardiac-death donors represent an extremely important and overlooked source of high-quality donor kidneys and have the potential to increase markedly the number of kidney transplants performed in the UK," said Professor Andrew Bradley who lead the study.
Full story at the Guardian
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TB or not TB.
Scientists from the Medical Research Council's National Institute for Medical Research have developed a blood test which is able to tell whether someone is likely to develop tuberculosis.
TB, caused by the bacterium Mycobacterium tuberculosis, kills up to 2 million people each year, and it is estimated that a third of the world’s population are infected by M. tuberculosis bacteria. However only 10% of those infected develop full TB. The remaining people simply carry a latent form of the disease, which lays dormant within them. It is unknown why some become sick, whilst others don’t, but the new test hopes to help determine those who will develop full TB.
The blood of over 400 people from London and Cape Town was analysed and a "genetic signature" was discovered in the blood of those who had the active form of the disease. This signature is comprised of specific molecules, found in a patient with full TB. It is also found in the 10% of those with latent TB, potentially identifying those who may go on to develop the full disease.
The signature appears to be independent of age, ethnicity and sex. The test can also identify the levels and severity of the disease. After successful treatment the signature is no longer detectable. It is hoped that this work will help doctors rapidly identify those who are at risk of developing TB.
"What such a test would enable is very targeted treatment. Instead of trying to treat everyone with latent TB you could focus all of your efforts on that 10 per cent who would develop the disease," said Dr Matthew Berry, a consultant in respiratory medicine.
Full story at the Independent
---------------
The game of (early) life.
The discovery of ancient sea sponge fossils pushes back the date which animal life existed on Earth by 90 million years, say scientists from Princeton University. The finds may be the oldest evidence of life ever discovered, and were found in an area of Australia which was once an ocean reef.
Sponges filter sea water through specialist channels in their body and extract the food it contains. The fossils, measuring 1 cm in length, are approximately 650 million years old. The previous oldest discovered sea-sponge fossils were approximately 520 million years old.
There is interest in these fossils because they show that life existed before the 'Snowball Earth', a catastrophic event around 635 million years ago that led to the entire planet being covered by ice. Previously it was thought that life evolved after this event.
The fossils were found by accident whilst scientists were searching for rocks containing clues as to the environmental conditions before the giant ice age.
Studying these particular fossils was difficult as they were completely encased in rock. X-ray analysis cannot be used to study rock encased fossils, as the fossils and the rocks surrounding them are made of the same substance and the X-rays are unable to identify the differences between them. In this case the scientists recreated a 3-D model of the fossils, by slicing the rocks containing them very finely and taking thousands of photographs.
Full story at the Daily Mail
---------------
A diet for healthy wellbeeing.
Researchers from the University of Worcester have suggested that bees living in urban environments have a richer and more varied diet than those living in the countryside.
The National Pollen and Aerobiology Research Unit analysed pollen samples from ten National Trust hives across the country to see what the bees were feeding on. Samples from Kensington Palace in London showed large amounts of pollen from rock rose, eucalyptus and elderberry. Samples taken from rural sites, such as Yorkshire or Somerset were dominated by pollen from a single source – oilseed rape. Bees living in suburban environments showed a mixture of oilseed rape and other pollen.
The research is trying to establish a link between the different types of pollen collected bees and their health and nutrition. It is feared that by living on a restricted diet, the country bees are more susceptible to agricultural sprays.
Matthew Oates from the National Trust explained that the preliminary findings are in line with what had been suspected - that urban bees fare better than their rural counterparts.
"Apart from crops such as oilseed rape and field beans, there are precious few pollen sources around for bees and other insects in modern arable farmland and surprisingly little in areas specialising in dairy, beef or sheep production," he said.
Full story at the Guardian
---------------
Big Bird’s larger, meaner, brother.
New research of a huge, flightless, meat eating bird from South America reveals how it attacked and devoured its prey.
Birds of the family Phorusrhacids lived in South America when it was still an island, around 50 million years ago. The birds were carnivorous, stood between one and three metres tall and had enormous beaks with a vicious hooked end. Their fearsome appearance gives the family its alternative name, the ‘Terror Birds’.
As nothing exists today that resembles a terror bird, little is known about the way they used their beaks to feed. The international team of scientists looked at the skull of a terror bird known as Andalgalornis, and revealed that it attacked its prey using a series of swift, powerful pecks. The large hook on the end of the beak probably resulted in death by a single blow. The bird was then free to rip flesh from its victim.
However, the research also revealed that the beak had to be used with some care. The team scanned the skull and assessed what it was capable of, using a technique known as finite element analysis (FEA). FEA allows scientists to test how structures respond to different mechanical stresses. The results revealed that the beak very well suited to a rapid jabbing motion, but was highly susceptible to fracture if it was used to grab and shake an object.
"These birds had enormous beaks with big hooks on the end. But we've shown they had to use those beaks with some precision and caution," said Dr Stephen Wroe, from the University of Sydney.
Full story at the BBC
---------------
New hope for those awaiting transplant.
The UK has some of the lowest organ donation rates in Europe and the acute lack of kidneys available for transplant leads to approximately 700 deaths each year. There are about 7,000 people awaiting a new kidney on the transplant waiting list, but only 2,500 operations take place each year. A Cambridge University study has shown results that may double the number of UK kidney transplants in the future saving hundreds of lives a year.
The majority of transplanted UK kidneys come from "brain dead" deceased donors, who have suffered serious head trauma, usually as a result of a traffic or work related incident. The decrease in road related deaths has led to a decrease in the number of kidneys available for transplant.
The new study tested kidneys taken from donors who died as a result of heart failure following a head trauma. Previously it was thought that DCD (donated after cardiac death) kidneys were inferior to those who had died from head trauma only. The research showed that transplanted DCD kidneys were equally as good at extending life as non DCD kidneys.
The study assessed 9,134 patients who received transplanted kidneys in 23 different UK transplant centres between 2000 and 2007. 845 DCD kidneys were used along with 8,289 kidneys received after brain death. Both types were equally effective at keeping a patient alive for at least 5 years.
"Cardiac-death donors represent an extremely important and overlooked source of high-quality donor kidneys and have the potential to increase markedly the number of kidney transplants performed in the UK," said Professor Andrew Bradley who lead the study.
Full story at the Guardian
---------------
TB or not TB.
Scientists from the Medical Research Council's National Institute for Medical Research have developed a blood test which is able to tell whether someone is likely to develop tuberculosis.
TB, caused by the bacterium Mycobacterium tuberculosis, kills up to 2 million people each year, and it is estimated that a third of the world’s population are infected by M. tuberculosis bacteria. However only 10% of those infected develop full TB. The remaining people simply carry a latent form of the disease, which lays dormant within them. It is unknown why some become sick, whilst others don’t, but the new test hopes to help determine those who will develop full TB.
The blood of over 400 people from London and Cape Town was analysed and a "genetic signature" was discovered in the blood of those who had the active form of the disease. This signature is comprised of specific molecules, found in a patient with full TB. It is also found in the 10% of those with latent TB, potentially identifying those who may go on to develop the full disease.
The signature appears to be independent of age, ethnicity and sex. The test can also identify the levels and severity of the disease. After successful treatment the signature is no longer detectable. It is hoped that this work will help doctors rapidly identify those who are at risk of developing TB.
"What such a test would enable is very targeted treatment. Instead of trying to treat everyone with latent TB you could focus all of your efforts on that 10 per cent who would develop the disease," said Dr Matthew Berry, a consultant in respiratory medicine.
Full story at the Independent
---------------
The game of (early) life.
The discovery of ancient sea sponge fossils pushes back the date which animal life existed on Earth by 90 million years, say scientists from Princeton University. The finds may be the oldest evidence of life ever discovered, and were found in an area of Australia which was once an ocean reef.
Sponges filter sea water through specialist channels in their body and extract the food it contains. The fossils, measuring 1 cm in length, are approximately 650 million years old. The previous oldest discovered sea-sponge fossils were approximately 520 million years old.
There is interest in these fossils because they show that life existed before the 'Snowball Earth', a catastrophic event around 635 million years ago that led to the entire planet being covered by ice. Previously it was thought that life evolved after this event.
The fossils were found by accident whilst scientists were searching for rocks containing clues as to the environmental conditions before the giant ice age.
Studying these particular fossils was difficult as they were completely encased in rock. X-ray analysis cannot be used to study rock encased fossils, as the fossils and the rocks surrounding them are made of the same substance and the X-rays are unable to identify the differences between them. In this case the scientists recreated a 3-D model of the fossils, by slicing the rocks containing them very finely and taking thousands of photographs.
Full story at the Daily Mail
---------------
A diet for healthy wellbeeing.
Researchers from the University of Worcester have suggested that bees living in urban environments have a richer and more varied diet than those living in the countryside.
The National Pollen and Aerobiology Research Unit analysed pollen samples from ten National Trust hives across the country to see what the bees were feeding on. Samples from Kensington Palace in London showed large amounts of pollen from rock rose, eucalyptus and elderberry. Samples taken from rural sites, such as Yorkshire or Somerset were dominated by pollen from a single source – oilseed rape. Bees living in suburban environments showed a mixture of oilseed rape and other pollen.
The research is trying to establish a link between the different types of pollen collected bees and their health and nutrition. It is feared that by living on a restricted diet, the country bees are more susceptible to agricultural sprays.
Matthew Oates from the National Trust explained that the preliminary findings are in line with what had been suspected - that urban bees fare better than their rural counterparts.
"Apart from crops such as oilseed rape and field beans, there are precious few pollen sources around for bees and other insects in modern arable farmland and surprisingly little in areas specialising in dairy, beef or sheep production," he said.
Full story at the Guardian
---------------
Big Bird’s larger, meaner, brother.
New research of a huge, flightless, meat eating bird from South America reveals how it attacked and devoured its prey.
Birds of the family Phorusrhacids lived in South America when it was still an island, around 50 million years ago. The birds were carnivorous, stood between one and three metres tall and had enormous beaks with a vicious hooked end. Their fearsome appearance gives the family its alternative name, the ‘Terror Birds’.
As nothing exists today that resembles a terror bird, little is known about the way they used their beaks to feed. The international team of scientists looked at the skull of a terror bird known as Andalgalornis, and revealed that it attacked its prey using a series of swift, powerful pecks. The large hook on the end of the beak probably resulted in death by a single blow. The bird was then free to rip flesh from its victim.
However, the research also revealed that the beak had to be used with some care. The team scanned the skull and assessed what it was capable of, using a technique known as finite element analysis (FEA). FEA allows scientists to test how structures respond to different mechanical stresses. The results revealed that the beak very well suited to a rapid jabbing motion, but was highly susceptible to fracture if it was used to grab and shake an object.
"These birds had enormous beaks with big hooks on the end. But we've shown they had to use those beaks with some precision and caution," said Dr Stephen Wroe, from the University of Sydney.
Full story at the BBC
---------------
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