QUESTION: What’s the difference between soluble and insoluble fiber? Are they both good for you, and how can I include them in my diet? ANSWER:Dietary fiber, the edible portions of plant cell walls that are resistant to digestion, is an …
Posts Tagged ‘National Academy Of Sciences’
Mother and newborn baby both die of the same cancer as scientists prove tumours can be caught in the womb
Normally an embryo’s immune system would recognise and attack cancer cells
Pregnant women can transmit cancer to their unborn babies, British scientists have proved for the first time.
In an ‘extremely rare’ case that challenges conventional wisdom about human biology, a mother with leukaemia passed the blood disease to her daughter.
Normally a child’s immune system would recognise and destroy any invasive cancer cells.
Although doctors know of 30 past cases of mothers and babies sharing the same cancer – usually leukaemia or the skin cancer melanoma – they have never before shown that the child’s disease definitely originated in the mother.
Professor Mel Greaves, who led the study at the Institute of Cancer Research in Sutton, Surrey, said the risks to unborn babies were extemely low.
‘It appears that in this and, we presume, other cases of mother to offspring cancer, the maternal cancer cells did cross the placenta into the developing foetus and succeeded in implanting because they were invisible to the immune system,’ he said.
‘We are pleased to have resolved this longstanding puzzle.
‘But we stress that such mother to offspring transfer of cancer is exceedingly rare and the chances of any pregnant woman with cancer passing it on to her child are remote.’
The study investigated a case in Japan in which a 28-year-old was diagnosed with leukaemia shortly after she gave birth.
Eleven months later, her daughter-was also diagnosed with the disease.
Genetic tests on the child’s blood cells showed that she had the cancer cells at birth and that they came from her mother, the journal Proceedings of the National Academy of Sciences reports.
Closer investigation revealed that the daughter’s leukaemia cells were missing a vital piece of DNA that would have flagged them up as ‘intruders’ to her immune system.
Without this, her system was unable to target and destroy th cancer cells and she went on to develop the disease.
A spokesman for the researchers said that the mother and daughter have both since died.
The researchers say the same mutation could allow melanoma cancer cells to pass from mother to baby.
However, they believe it is unlikely that other cancers could be passed on this way.
Professor Peter Johnson, of Cancer Research UK, said: ‘This is an extremely unusual case, but this study is particularly revealing because it suggests that the cancer cells could only cause a problem in the baby by evading their immune system.
‘This is really important research as it adds to the evidence that cancers need to evade the immune system before they can grow, giving hope that by alerting a patient’s immune system to a cancer we can develop new types of treatment.
‘Women needing cancer treatment-around the time of having a baby who are worried about this research should speak to the specialists looking after them for advice.’
Dr David Grant, scientific director at charity Leukaemia Research, added: ‘The important message from this fascinating piece of research is that leukaemia cells can be destroyed by the immune system.
He added: ‘Harnessing the power of the immune system to first cure and then protect patients from leukaemia is one of our priority areas of research.’
Cancer in pregnancy is rare, with only one in 1,000 pregnant women thought to be affected by the disease.
The outcome for mother and child depends on the type of cancer and the stage at which it is discovered.
Digital multi-tasking could be bad for the brain, scientists say.
A study showed that those who browse the internet while texting friends and listening to music do worse in simple mental tests.
They are more easily distracted and, ironically, find it harder to switch between tasks than people who concentrate on one thing at a time, the researchers say.
Those who browse the internet while texting friends and listening to music do worse in simple mental tests, a study found
The findings add to evidence that ‘ digital overload’ is interfering with the way people think and behave.
Some neuroscientists argue that the brain is geared to handle one thing at a time. When asked to juggle several things at once, it is forced to flick frantically between them, like a performer spinning plates.
This puts the brain under stress and means it doesn’t perform as well, it is claimed.
The study by researchers from Stanford University, California, classified 262 students into ‘heavy’ or ‘light’ multi-taskers and compared their performance in a series of computerised mental tests.
The heavy multi-taskers had much more difficulty filtering out irrelevant information from their environment and their memory, the journal Proceedings of the National Academy of Sciences reports.
They also found it more difficult to switch from one task to another and performed worse in the tests.
Communication expert Professor Clifford Nass said: ‘In an ever more saturated media environment, media multi-tasking – a person’s consumption of more than one item or stream of content at the same time – is becoming an increasingly prevalent phenomenon, especially among the young.
‘These results demonstrate that media multi-tasking is associated with a distinct approach to fundamental information processing.’
But he added that it was unclear if multi-tasking caused people to become distracted, or whether those prone to distraction preferred to surround themselves with electronic media.
Earlier this year Susan Greenfield, an Oxford University neuroscientist and director of the Royal Institution, warned that websites such as Twitter and Facebook could be triggering changes in the brains of millions of young people.
This was ‘infantilising’ them and robbing them of traditional social skills, she said.
Multi-tasking could be more harmful for teenagers than adults because their brains are still developing. Once a young person’s brain has been conditioned to multi-task, they may struggle to concentrate later in life.
A cheap blood pressure drug could hold the key to combating multiple sclerosis.
An MS expert has shown that the tablets taken by millions to lower blood pressure can also ease the symptoms – and even reverse paralysis.
Lawrence Steinman made the link when he researched the Lisinopril pills he was prescribed for high blood pressure.
Drugs currently used to treat MS, in which the immune system turns on the body, are of limited effectiveness and do not work for everyone.
Some cost up to £15,000 a year. Lisinopril, in contrast, costs as little as 2p per pill.
It is one of a group of drugs called ACE-inhibitors that lowers blood pressure by blocking a chemical that is key in the narrowing of blood vessels.
Research by Dr Steinman indicated that the chemical, called angiotensinconverting enzyme, also played a role in the inflammation responsible for much of the damage caused by MS.
Dr Steinman, of Stanford University in the U.S., showed that samples of brain tissue from MS patients had high levels of angiotensin-converting enzyme.
He then gave Lisinopril to mice before giving them a chemical that normally causes an MS-like illness in mice.
The creatures remained healthy, suggesting the blood pressure drug was holding MS at bay.
Strikingly, when he gave Lisinopril to mice after giving them the MS-causing chemical, paralysis was reversed, the journal Proceedings of the National Academy of Sciences reports.
Tests showed that Lisinopril boosted production of immune cells called regulatory T cells.
These protect against autoimmune diseases such as MS by dampening down the rogue immune response that damages the body. Dr Steinman called for Lisinopril to be tested on patients.
He cautioned though that drugs that work in mice don’t necessarily work in humans.
Dr Susan Kohlhaas, of the MS Society, said: ‘Drugs that dampen down an overactive immune system have been shown to be of some benefit to people with MS and intriguingly it seems Lisinopril may have this effect.
‘It remains to be seen whether Lisinopril can play a role in preventing the onset or slowing the progression of MS. The only way to judge this is through larger clinical studies in humans.’
Scientists have made teeth from stem cells in a world first that could make dentures a thing of the past.
They looked like normal teeth, were sensitive to pain and chewed food easily.
While the experiments were on mice, they pave the way for people to ‘grow their own teeth’ as required.
The technique could also be adapted to other organs, allowing hearts, lungs and kidneys to be grown inside the body to replace parts worn by age or damaged by disease.
The Japanese study focused on stem cells – ‘master cells’ with the ability to turn into other cell types.
The researchers from the Tokyo University of Science identified two types of stem cell, which together contain all the instructions for a fully grown tooth.
The cells were grown in the laboratory for five days until they formed a tiny tooth ‘bud’.
This was then transplanted deep into the jawbone of a mouse that had had a tooth removed.
Five weeks later, the tip of the tooth broke through the gum. And after seven weeks, it was fully-grown, the journal Proceedings of the National Academy of Sciences reports.
The researchers, who repeated the experiment many times, also showed that the new, bioengineered teeth were fully-functional.
Dr Kazuhisa Nakao said: ‘Every bio- engineered tooth erupted through the gum and had every tooth component such as dentine, enamel, pulp, blood vessels, nerve fibres, crown and root.’
Importantly, the rodent recipients had no trouble eating.
The cells used were take from mouse embryos, but the researchers believe it should be possible to make teeth from other types of cell as well.
They are now looking for suitable cells in people. Possibilities include skin cells and cells from the pulp inside teeth.
They also have to work out how to control the size of the bio-engineered teeth, as those grown in the experiments were slightly smaller than usual.
The process would also have to be speeded up if it was to be used on people as human teeth take years to form.
Experts believe that using ‘living’ teeth rather than artificial ones would be better for oral health and may also provide a more natural ‘bite’. Bio- engineered teeth are likely to cost around £2,000 each – a similar price to the implants used at the moment.
But Britain’s 11 million denture wearers should not throw away their fixative creams and gels quite yet.
The technology is still at a very early stage and the Japanese researchers believe it will not be widely used by dentists for at least 15 years. Despite this, British experts said it was an important landmark.
Professor Robin Lovell-Badge, a stem cell researcher at the National Institute for Medical Research in London, said the work was ‘excellent’ and highlighted the promise of using bio-engineering to make complex structures.
But he cautioned that the researchers had yet to find cells suitable for use in people.
Professor Damien Walmsley, of the British Dental Association, said: ‘If you lose a tooth at the moment, one of the options is a metal implant. If you could have a natural replacement, that would be good.’
Natural-looking replacements-also have massive psychologicalbenefits for self-conscious patients.
The technique of creating cell ‘buds’ could be applied more widely to grow other organs, such as hearts, kidneys and livers, inside the body.
Lead researcher Professor Takashi Tsuji said: ‘The ultimate goal of regenerative therapy is to develop fully-functioning bioengineered organs that can replace lost or damaged organs following disease, injury or ageing.
‘Our study makes a substantial contribution to the development of bio- engineering technology for future organ replacement therapy.’
After one of the longest sunspot droughts in modern times, solar activity picked up quickly over the weekend.
A new group of sunspots developed, and while not dramatic by historic standards, the spots were the most significant in many months.
“This is the best sunspot I’ve seen in two years,” observer Michael Buxton of Ocean Beach, Calif., said on Spaceweather.com.
Solar activity goes in a roughly 11-year cycle. Sunspots are the visible signs of that activity, and they are the sites from which massive solar storms lift off. The past two years have marked the lowest low in the cycle since 1913, and for a while scientists were wondering if activity would ever pick back up.
During 2009 so far, the sun has been completely free of spots about 77 percent of the time. NASA researchers last month said quiet jet streams inside the sun were responsible, and that activity would soon return to normal.
The new set of spots, named 1024, is kicking up modest solar flares.
Sunspots are cool regions on the sun where magnetic energy builds up. They serve as a cap on material welling up from below. Often, that material is released in spectacular light shows called solar flares and discharges of charged particles known as coronal mass ejections. The ejections can travel as space storms to Earth within a day or so, and major storms can knock out satellites and trip power grids on the surface.
Prior to the low-activity period, astronomers had been predicting that the next peak in solar activity, expected in 2013, might be one of the most active in many decades. That forecast was recently revised, however, and scientists now expect the next peak to be modest.
All this matters because, as laid out in a report earlier this year by the National Academy of Sciences, a major solar storm nowadays could cause up to $2 trillion in initial damages by crippling communications on Earth and fueling chaos among residents and even governments in a scenario that would require four to 10 years for recovery. Such a storm struck in 1859, knocking out telegraph communications and causing those lines to erupt in flames. The world then was not so dependent on electronic communication systems, however.
Lower Increases In Global Temperatures Could Lead To Greater Impacts Than Previously Thought, Study Finds
From Science Daily:
ScienceDaily (Mar. 1, 2009) — A new study by scientists updating some of the findings of the Intergovernmental Panel on Climate Change (IPCC) 2001 Third Assessment Report finds that even a lower level of increase in average global temperatures due to greenhouse gas emissions could cause significant problems in five key areas of global concern.
The study, published in the Proceedings of the National Academy of Sciences, is titled “Assessing Dangerous Climate Change Through an Update of the IPCC ‘Reasons for Concern.”
Read more ….
From Science Daily:
ScienceDaily (Feb. 24, 2009) — Researchers have identified the gene that ultimately controls the production of tooth enamel, a significant advance that could some day lead to the repair of damaged enamel, a new concept in cavity prevention, and restoration or even the production of replacement teeth.
The gene, called Ctip2, is a “transcription factor” that was already known to have several functions – in immune response, and the development of skin and the nervous system. Scientists can now add tooth development to that list.
The findings were just published in the Proceedings of the National Academy of Sciences.
Read more ….
From International Herald Tribune:
Forensic evidence that has helped convict thousands of defendants for nearly a century is often the product of shoddy scientific practices that should be upgraded and standardized, according to accounts of a draft report by the nation’s pre-eminent scientific research group.
The report by the National Academy of Sciences is to be released this month. People who have seen it say it is a sweeping critique of many forensic methods that the police and prosecutors rely on, including fingerprinting, firearms identification and analysis of bite marks, blood spatter, hair and handwriting.
Read more ….
From Science Daily:
ScienceDaily (Feb. 4, 2009) — A variation in the gene FOXO3A has a positive effect on the life expectancy of humans, and is found much more often in people living to 100 and beyond – moreover, this appears to be true worldwide.
A research group in the Faculty of Medicine at the Christian-Albrechts-University in Kiel (CAU) has now confirmed this assumption by comparing DNA samples taken from 388 German centenarians with those from 731 younger people. The results of the study appear this week in the journal Proceedings of the National Academy of Sciences (“PNAS”).
Read more ….