Proteins in unroasted coffee beans pave way for new insecticides

May 21, 2010 By Leave a Comment

Washington, May 21 (ANI): Scientists in Brazil have found that unroasted coffee beans contain proteins that can kill insects, a finding that may lead to new insecticides for protecting food crops.

The study suggests a new use for one of the most important tropical crops in the world.

Peas, beans and some other plant seeds contain proteins, called globulins, which ward off insects. Coffee beans contain large amounts of globulins, and Paulo Mazzafera and colleagues wondered whether those coffee proteins might also have an insecticidal effect.

The high heat of roasting destroys globulins, so that they do not appear in brewed coffee.

Their tests against cowpea weevil larva, insects used as models for studying the insecticidal activity of proteins, showed that tiny amounts of the coffee proteins quickly killed up to half of the insects.

In the future, scientists could insert genes for these insect-killing proteins into important food crops, such as grains, so that plants produce their own insecticides, the researchers suggest. The proteins appear harmless to people.

The study appears in ACS” Journal of Agricultural and Food Chemistry, a bi-weekly publication. (ANI)

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Creator of first synthetic living cell claims he’s not playing god

May 21, 2010 By Leave a Comment

London, May 21 (ANI): Dr Craig Venter, who has created the first synthetic living cell, has said that he is not playing god, but the feat could help them understand the basic nature of life.

In a recent interview Venter as said that what he has achieved is indeed the first in the world.

“This is the first time anyone has built an entire 1.08 million base pair chromosome, transplanted that chromosome into a recipient cell and for that chromosome to take over that cell, effectively converting it into a new species defined by the chromosome. So it”s a whole new paradigm, the first time we have a cell that is totally controlled 100 per cent by a synthetic chromosome,” the Independent quoted him as saying.

“We”re defining it as synthetic life because it”s totally determined by the synthetic chromosome. We do start with a living cell but the synthetic chromosome totally transforms that living cell to this new synthetic cell,” he added.

When asked if the new form of life is a replicating, free-living organism, he said: “That is correct, only it is only free-living in the sense that it grows in the laboratory in a very rich culture media so it wouldn”t survive in the outside environment. Given the right nutrients in the laboratory it is completely self-replicating on its own.”

And he said that the discovery could help scientists in many ways.

“The purpose is to try to understand the basic nature of life, and the minimal sets of genes needed for life. We do not know all the gene functions in any single cell. We don”t know what they do, we don”t know how they all work so we”ve been trying for 15 years to come up with ways to be able to define that even for simple cells.

“So that is the key part of the next stage. But over the years the uses of this technology have become much more apparent to us and to others. It”s a powerful technology for actually trying to design specific functions into organisms, for example to manufacture new fuels out of carbon dioxide or to create new vaccines very rapidly instead of the long delays we have.”

Asked, if he is playing God with life, he replied: “We”ve covered this before because it”s almost a cliché every time there”s a new breakthrough in science, particularly in biology. Science is understanding life at its most basic levels and trying to use that knowledge for the betterment of humanity so I think we are part of the progression of scientific knowledge and understanding of the world around us.”

On the chances of the technology being misused, he said: “We have to be concerned. It”s a powerful technology and I”ve proposed new regulations in this field because I feel the existing ones don”t go far enough. Because we”re the inventors and developers of this we want to see everything that can be done to prevent misuse of this technology.”

“I”ve proposed regulating the companies that synthesise DNA, to screen [the DNA being synthesised] against harmful agents, and we”ve given feedback on improving those screens and being more rigorous. I”ve been briefing the US Congress on this.

“We don”t want people taken by surprise. We want to put this breakthrough into context in terms of what it means. We”re trying to take every responsible step we can in that respect.

“I think this is the first incidence in science where the extensive bioethical review took place before the experiments were done.

“It”s part of an ongoing process that we”ve been driving, trying to make sure that the science proceeds in an ethical fashion, that we”re being thoughtful about what we do and looking forward to the implications to the future,” he added. (ANI)

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It’s official: Men lie more than women

May 18, 2010 By Leave a Comment

London, May 18 (ANI): A new study has confirmed what many ladies already knew: Men tell more lies than women.

According to the study, on an average, a man will tell three lies a day, racking up 1,092 whoppers in a year. However, an average woman will come out with 728, fibbing just twice a day, reports The Daily Express.

The study, which was commissioned by researchers at the Science Museum in London, found that 82 per cent of females questioned said telling a lie ate away at their conscience but only 70 per cent of men confessed to suffering pangs of guilt.

“Lying may seem to be an unavoidable part of human nature but it’s an important part of social interaction,” said Katie Maggs, the museum’s associate medical curator.

“The jury is still out as to whether human quirks like lying are the result of our genes, evolution or our upbringing.”

OnePoll spoke to 3,000 adults for the survey.

The top 10 lies men tell their partners include “I had no signal”, “I’m on my way”, “I’m stuck in traffic”, “Sorry, I missed your call”, “You’ve lost weight” and “It’s just what I’ve always wanted”. (ANI)

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How eavesdropping on sexual signals helps young male crickets

May 13, 2010 By Leave a Comment

Washington, May 13 (ANI): Sexual signals do more than just attract mates – in the case of crickets, says a new study.

Adult male crickets produce loud song to lure females, but the song can be overheard also by unintended receivers – such as young males unable to produce song due to a mutation they carry.

So far, researchers have not understood how non-singing male crickets use the song of singing males to modify their behavior or physical attributes to their advantage. Now, researchers at the University of California, Riverside have shed light on this mystery.

As part of the research, the scientists exposed one set of juvenile male crickets to a silent environment (which mimicked a population without very many singing males) and a second set of young male crickets to a song-rich environment (mimicking a population that contained lots of singing males).

Comparing the two sets of data, they found that male crickets growing up in the presence of abundant male song tend to be larger than male crickets growing up in a silent environment, and invest nearly 10 percent more reproductive tissue mass in their testes.

The researchers also found that male crickets that do not hear song during rearing are more likely to act as ”satellites,” hanging out near singing males and intercepting females on their way for matings.

“Subtle modifications of behavior depending on the environment, not genes, means that even in insects, animals aren”t ”programmed” or ”hard-wired” to do what they do,” said Marlene Zuk, a professor of biology, whose lab conducted the research.

Nathan Bailey, the lead author of the research paper, said: “Larger is probably better for the crickets because it allows males to better compete against other males in their environment. Being flexible according to who is around can be beneficial and help maximize the chance of reproducing.”

The new research suggests that sexual signals may play a hitherto under-appreciated role in determining how an animal looks and behaves once it grows up.

“Sexual signals do more than just attract mates. They can also influence other animals” development just by virtue of being perceived. The ability to change oneself according to the prevailing social conditions might be adaptive, especially in an environment that is constantly changing,” Bailey explained.

“On a more global scale, people often think of insects, especially the non-social insects, as mindless automatons, pre-programmed to carry out simple procedures throughout their lives.

“Our research shows quite the opposite, and demonstrates how even small, inconspicuous animals respond to the vagaries of their social environment by capitalizing on conspicuous signals that are intended for a different receiver,” Bailey added.

The study results appeared May 11 in the journal Current Biology. (ANI)

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Why breast milk is the best

May 13, 2010 By Leave a Comment

Washington, May 13 (ANI): Scientists at the University of Illinois have discovered why breast milk is better than infant formula.

“For the first time, we can see that breast milk induces genetic pathways that are quite different from those in formula-fed infants. Although formula makers have tried to develop a product that”s as much like breast milk as possible, hundreds of genes were expressed differently in the breast-fed and formula-fed groups,” said Sharon Donovan, a U of I professor of nutrition.

Although both breast-fed and formula-fed babies gain weight and seem to develop similarly, scientists have known for a long time that breast milk contains immune-protective components that make a breast-fed infant”s risk lower for all kinds of illnesses, she said.

“The intestinal tract of the newborn undergoes marked changes in response to feeding. And the response to human milk exceeds that of formula, suggesting that the bioactive components in breast milk are important in this response. What we haven”t known is how breast milk protects the infant and particularly how it regulates the development of the intestine,” she said.

Understanding those differences should help formula makers develop a product that is more like the real thing, she said. The scientists hope to develop a signature gene or group of genes to use as a biomarker for breast-fed infants.

Many of the differences found by the scientists were in fundamental genes that regulate the development of the intestine and provide immune defence for the infant.

In the study, Donovan used a new technique to examine intestinal gene expression in 22 healthy infants—12 breast-fed, 10 formula-fed.

The technique involved isolating intestinal cells shed in the infants” stools, then comparing the expression of different genes between the two groups. Mothers in the study collected fecal samples from their babies at one, two, and three months of age. Scientists were then able to isolate high-quality genetic material, focusing on the RNA to get a gene expression or signature.

Donovan said that intestinal cells turn over completely every three days as billions of cells are made, perform their function, and are exfoliated. Examining the shed cells is a non-invasive way to examine intestinal health and see how nutrition affects intestinal development in infants.

Understanding early intestinal development is important for many reasons, she said.

The study will appear in the June 2010 issue of the American Journal of Physiology, Gastrointestinal and Liver Physiology. (ANI)

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Soon, ‘magic pill’ that will allow people to live beyond 100

May 11, 2010 By Leave a Comment

London, May 11 (ANI): Scientists are developing a new pill, which, if taken at 40, could boost a person’s chances of living longer.

Prof Nir Barzilai, director of the Institute of Ageing at the Albert Einstein College of Medicine in New York, said that one can go on to live for 100 years despite following a poor diet and even smoking, only if their genes are programmed for longevity.

Those who lived very long lives were genetically programmed to do so, which insulated them from the effects of “environmental” factors like smoking and a poor diet.

The professor studied 500 Jewish people between 95 and 112.

“These people smoked, they are overweight, they have high cholesterol,” the Telegraph quoted him as saying.

He said about 30 per cent of them were obese, while 30 per cent of them had smoked to the age of 95.

“They are protected from the environment by their genotype,” he said.

Living a healthy life might help most people increase their life expectancy by a few years, but it won’t be of any use for those who wanted to live much longer, he said.

His findings support anecdotal stories of countless people who have lived to a grand old age seemingly in spite of smoking, lack of exercise or a poor diet.

He said that centenarians tended to have genes, which delayed the onset of age-related illnesses like heart disease and Alzheimer”s.

“When they eventually die, they die of the same things that people die of in their 70s or 80s. It”s just that they die 30 years later,” he said.

Identifying these genes opened the doorway to developing longevity drugs, which mimicked their effects, he said.

The researchers have already identified a number of such genes among the centenarians.

Laboratories are now working on creating a drug which mimics the effects of three of them – two that increase the production of so-called ”good” cholesterol in the body, which reduces the risk of heart disease and stroke, and a third that helps prevent diabetes.

Barzilai said that testing could begin by 2012, with it appearing on the market “within five or 10 years”.

“People will take a pill, starting at 40, and their lives will be longer,” he predicted.

Barzilai will address the Royal Society in London on the subject of ”interfering with ageing to treat ageing-related disease”. (ANI)

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Soon, an early warning test for breast cancer

May 10, 2010 By Leave a Comment

London, May 10 (ANI): An early warning test could soon be able to detect breast cancer.

British scientists have come closer to developing such a test, which could save the lives of millions of women.

They have discovered five more cancer-causing genetic mutations on top of the 13 already known.

“By finding more of these genes we may be able to develop a test that can predict more reliably a woman’s risk of developing breast cancer,” the Daily Express quoted Professor Doug Easton of Cambridge University as saying.

His report is published in the journal Nature Genetics. (ANI)

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Drugs that could ‘switch on’ memory offer hope to Alzheimer”s sufferers

May 7, 2010 By Leave a Comment

London, May 7 (ANI): Scientists have identified a genetic switch that causes memory impairment in mice when it goes into ‘off’ mode, raising hopes of powerful new drugs to treat Alzheimer”s and other diseases.

As part of their research, Andre Fischer of the European Neuroscience Institute in Gottingen, Germany, and colleagues forced 3-month-old mice to find their way around a new environment and assessed them on their ability to associate an electric shock with a particular environment.

The result was increased activity of a cluster of over 1500 genes, which are known to make proteins that are needed for the creation of new neurons – a process that is necessary for learning in humans and mice, reports New Scientist.

This boost in gene expression did not occur in 16-month-old mice given the same tasks: the activity of their genes changed only slightly. The mice also did worse than the young ones at spatial learning and memory tasks.

To find out what prevents elderly mice getting this genetic boost, the researchers analysed the DNA found in neurons in the hippocampus of both old and young mice.

They found that when young mice are learning, a molecular fragment known as an acetyl group binds to a particular point on the histone protein that DNA wraps itself around – with the result that the cluster of learning and memory genes on the surrounding DNA ends up close to the acetyl group. This acetyl ‘cap’ was missing in the older mice that had been set the same tasks.

From this, the team concluded that the cap acts as an ‘on’ switch for the cluster of learning and memory genes: removing the cap switches off the genes.

Next, by injecting an enzyme known to encourage caps to bind to any kind of histone molecule, Fischer”s team artificially flipped the switch to the on position in old mice.

The acetyl group returned to the histone molecule and the mice”s learning and memory performance became similar to that of 3-month-old mice.

The study has been published in the journal Science. (ANI)

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Turn 100 with a little help from your friends

May 5, 2010 By Leave a Comment

The secret to reaching 100 years of age is not based on genetics but having a healthy, happy lifestyle surrounded by family and friends, a study says.

Reaching the ripe old age of 100 used to be a rare event but now it is a growing phenomenon.

By 2020 it is expected there will be more than 12,000 centenarians in Australia.

As part of the study, researchers at the University of New South Wales interviewed more than 200 centenarians.

Professor Robyn Richmond said the centenarians shared common traits, including not smoking or drinking excessively and maintaining their weight throughout their lives.

She said lifestyle played a bigger role than genetics.

“About 20 to 30 per cent of the likelihood of living to 100 is because of your genes, so we know that longevity does run in families,” she said.

“If your parents lived to a ripe old age [then] your brothers and sisters and you are likely to also live to a very long age.

“Not always, of course, but it can be, so that leaves the environmental factors about 70 to 80 per cent.”

Being optimistic, open to change and being resilient were also common characteristics.

Professor Richmond said those surveyed had lower levels of depression that the rest of the community and lower levels of cardiac disease than people in their 80s.

And she said having good relationships was equally important.

“Certainly social contact with family and friends is very important,” she said.

“For example, if they don’t have children, if they have very strong connections with their friends or if they are living in a nursing home [and] they are part of a good organisation that gets them going and busy and doing interesting things with the other people who live there, they are more likely to live to 100.”

The findings of the study were released at the International Federation on Ageing Conference in Melbourne today.

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Exercise can help fight ‘obesity’ gene

May 5, 2010 By Leave a Comment

Washington, May 5 (ANI): Physically active lifestyle during adolescence can reduce the effect of a mutation in a gene that predisposes someone to becoming overweight or obese, says a study led by Spanish researchers.

Among the genes correlated to obesity, the FTO (or fat mass gene) is one of the genes responsible for the accumulation of fat in humans.

“Each copy of the mutation of this gene is associated with an increase of 3.3 lbs. This means that people who have two copies can weigh 6.6 lbs more than those who have no copies”, said Jonatan Ruiz, study’s lead author and researcher at the Karolinska Institute in Stockholm (Sweden).

The authors based their research on data collected in the European study HELENA, led by the University of Zaragoza, which analyses the effect of the FTO gene on weight and body fat in adolescents from nine European countries, among them, Spain.

“For young people, one hour of sport per day is enough to reduce the potential risk of this genetic mutation,” Ruiz said.

The study has been published in the journal Archives of Paediatrics & Adolescent Medicine. (ANI)

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Genes associated with osteoporosis identified

May 4, 2010 By Leave a Comment

London, May 4 (ANI): Researchers at Jewish General Hospital in Montreal have identified 20 genes associated with osteoporosis and bone weakness, including 13 genes never previously associated with the disease.

Osteoporosis is a highly heritable trait, but this marks the largest international effort to conclusively identify genes linked to the often-devastating bone disorder.

The study”s co-first author is Dr. J. Brent Richards of the Lady Davis Institute for Medical Research at the Jewish General Hospital in Montreal, who collaborated with more than 30 co-authors worldwide.

The results were published recently in the journal Nature Genetics.

The researchers reviewed data collected from nearly 20,000 individuals in five recent international genetic studies. (ANI)

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Blame your genes for credit card debt

May 4, 2010 By Leave a Comment

London, May 4 (ANI): A gene linked with impulsive and addictive behaviour makes people up to 16 per cent more likely to have credit card debt, a study has found.

The study was conducted by researchers from the London School of Economics and the University of California, reports The Independent.

Gene MAOA is associated with neurotransmitters which affect mood, and can be either “efficient” or “inefficient” at controlling mood chemicals.

Every human has a pair of the genes.

However, those with one “inefficient” MAOA gene were found to be 8 per cent more likely to have credit card debt than those with none, and for those with two the likelihood increased by 16 per cent, the study of 2,500 people found. (ANI)

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Two new genes linked to autism

May 3, 2010 By Leave a Comment

Washington, May 3 (ANI): Scientists have identified two additional genes that may be associated with autism.

Study co-author Ning Lei, a researcher at Princeton University and the Institute for Advanced Studies, said that there is no known cause of autism, but mutations of several genes have been linked to autism.

For the study, Dr. Lei and her colleagues analyzed data from the Autism Genetic Resource Exchange (AGRE) on 943 families, most of whom had more than one child diagnosed with autism and had undergone genetic testing.

The researchers compared the prevalence of 25 gene mutations in the AGRE families with a control group of 6,317 individuals without developmental or neuropsychiatric illness.

The researchers identified mutations in four genes within the AGRE families. Two of the genes previously were shown to be associated with autism and often are involved in forming or maintaining neural synapses — the point of connection between individual neurons.

One of the new genes identified was neural cell adhesion molecule 2 (NCAM2). NCAM2 is expressed in the hippocampus of the human brain — a region previously associated with autism.

“While mutations in the NCAM2 gene were found in a small percentage of the children that we studied, it is fascinating that this finding continues a consistent story — that many of the genes associated with autism are involved with formation or function of the neural synapse. Studies such as this provide evidence that autism is a genetically based disease that affects neural connectivity,” Dr. Lei said.

The researchers hypothesize that a substantial percentage of children with autism will be shown to have a mutation in one or more of the many genes necessary for normal function of the synapse.

The study also showed that some parents and siblings of children with autism have the NCAM2 mutation but do not have the disorder themselves.

This suggests that other environmental or genetic factors are involved in causing autism in susceptible individuals.

“These results help the public understand that autism is a very complex disorder, much like cancer and no single gene or gene environment is likely to be causative in most cases,” Dr. Lei said.

The findings have been presented at the Pediatric Academic Societies (PAS) annual meeting in Vancouver, British Columbia, Canada. (ANI)

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Sodas, processed foods can accelerate signs of aging

April 27, 2010 By Leave a Comment

Washington, Apr 27 (ANI): High levels of phosphate in sodas and processed foods can accelerate the aging process in mice and contribute to age-associated complications such as chronic kidney disease, claims a new study.

The study has been published in the FASEB Journal.

“Humans need a healthy diet and keeping the balance of phosphate in the diet may be important for a healthy life and longevity,” said M. Shawkat Razzaque, M.D., Ph.D., from the Department of Medicine, Infection and Immunity at the Harvard School of Dental Medicine. “Avoid phosphate toxicity and enjoy a healthy life.”

To reach the conclusion, Razzaque and colleague examined the effects of high phosphate levels in three groups of mice. The first group of mice was missing a gene (klotho), which when absent, causes mice to have toxic levels of phosphate in their bodies. These mice lived 8 to 15 weeks.

The second group of mice was missing the klotho gene and a second gene (NaPi2a), which when absent at the same time, substantially lowered the amount of phosphate in their bodies. These mice lived to 20 weeks. The third group of mice was like the second group (missing both the klotho and NaPi2a genes), except they were fed a high-phosphate diet. All of these mice died by 15 weeks, like those in the first group. This suggests that phosphate has toxic effects in mice, and may have a similar effect in other mammals, including humans.

“Soda is the caffeine delivery vehicle of choice for millions of people worldwide, but comes with phosphorous as a passenger” said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal. “This research suggests that our phosphorous balance influences the aging process, so don”t tip it.” (ANI)

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Gene silencing could be behind induced pluripotent stem cells” limitations

April 26, 2010 By Leave a Comment

London, Apr 26 (ANI): Getting closer to generate any type of cells and tissues from patient”s own cells, scientists have found that an important cluster of genes is inactivated in induced pluripotent stem cells (iPSCs) that do not have the full development potential of embryonic stem cells.

Generated from adult cells, iPSCs have many characteristics of embryonic stem cells but also have had significant limitations.

“We found that a segment of chromosome 12 containing genes important for fetal development was abnormally shut off in most iPSCs. These findings indicate we need to keep improving the way we produce iPSCs and suggest the need for new reprogramming strategies,” Nature quoted Dr. Konrad Hochedlinger, of the Massachusetts General Hospital Center for Regenerative Medicine (MGH-CRM) and the Harvard Stem Cell Institute (HSCI), who led the study.

Although iPSCs appear quite similar to embryonic stem cells and give rise to many different types of cells, they have important limitations.

Several molecular differences have been observed, particularly in the epigenetic processes that control which genes are expressed, and procedures that are able to generate live animals from the embryonic stem cells of mice are much less successful with iPSCs.

Previous studies have compared iPSCs generated with the help of viruses, which can alter cellular DNA, to embryonic stem cells from unrelated animals.

To reduce the chance that the different sources of the cells were responsible for observed molecular differences, the MGH/HSCI research team prepared two genetically matched cell lines.

After generating mice from embryonic stem cells, they used a technique that does not use viruses to prepare lines of iPSCs from several types of cells taken from those animals.

They then compared the iPSCs with the original, genetically identical embryonic stem cells.

The most stringent assay of cells” developmental potential showed that two tested lines of embryonic stem cells were able to generate live mice as successfully as in previous studies, but no animals could be generated from genetically matched iPSCs.

Closely comparing RNA transcription profiles of several matched cell lines revealed significantly reduced transcription of two genes in the iPSCs.

Both genes are part of a gene cluster on chromosome 12 that normally is maternally imprinted – meaning that only the gene copies inherited from the mother are expressed.

Examination of more than 60 iPSCs lines developed from several types of cells revealed that this gene cluster was silenced in the vast majority of cell lines.

While the gene-silenced iPSCs could generate many types of mouse tissues, their overall developmental potential was limited.

In an assay that produces chimeric animals that incorporate cells from two different stem cells, mice produced from gene-silenced cells had very few tissues that originated from the iPSCs.

However, in a few iPSC lines the gene cluster was normally activated, and in the most rigorous developmental assay, those iPSCs were as successful in producing live animals as embryonic stem cells have been.

According to the authors, this is the first report of animals being produced entirely from adult-derived iPSCs.

The study will appear in the journal Nature. (ANI)

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Bile sends mixed signals to gut bacteria for boosting survival

April 1, 2010 By Leave a Comment

Washington, Apr 1 (ANI): In the small intestine, bile secretions send signals to disease causing gut bacteria enabling them to change their behaviour to extend their chances of survival, according to a Montana State University scientist.

The findings by Steve Hamner and colleagues could allow us to better protect food from contamination by these harmful bacteria, as well as understand how they manage to cause disease.

Bile is secreted into the small intestine and exerts an antibacterial effect by disrupting bacterial membranes and damaging bacterial DNA, said the study.

While bile is a human defense mechanism, the researchers found that some bacteria such as Escherichia coli O157:H7 — an important food-borne pathogen known as E. coli — have evolved to use the signal to their advantage.

These bacteria use the presence of bile as a signal to tell them that they are in the intestine, which allows them to adapt and prepare to cause disease.

They found that bile causes the bacteria to switch on genes needed to increase iron uptake.

“This is useful in iron-scarce environments — such as the small intestine — as iron is an essential nutrient for bacterial growth. By increasing its chances of absorbing iron, the bacterium is maximizing its survival chances,” explained Hamner.

E. coli O157:H7 primarily infects the large intestine, and this study provides one explanation why this is the case.

“We found that bile causes the bacteria to turn off genes that promote tight attachment to host cells. Bile may effectively prevent these bacteria from latching onto the epithelial cells that line the small intestine,” suggested Hamner.

As bacteria move further down the digestive tract towards the large intestine, the concentration of bile decreases.

“The reduced concentration of bile in the large intestine may then be a signal for the bacteria to switch on their ability to attach to epithelial cells and to prepare to secrete toxins,” said Hamner.

Studying the conditions that make these bacteria more likely to attach themselves to cells could help reduce outbreaks of food poisoning.

“By learning how the bacteria attach to food surfaces such as spinach leaves or to host tissues such as the lining of the intestine, we hope to better be able to protect food sources from contamination by these bacteria. Studying how these bacteria interact with hosts such as humans or cows could teach us how to interfere with the way that these bacteria cause disease,” said Hamner.

The study was presented at the Society for General Microbiology during its spring meeting in Edinburgh, Scotland. (ANI)

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Unroasted coffee beans the next-gen insecticides?

April 1, 2010 By Leave a Comment

Washington, Apr 1 (ANI): Proteins in unroasted coffee beans may become next-generation insecticides, scientists in Brazil have reported.

The boffins claimed that coffee beans contain proteins that can kill insects and might be developed into new insecticides for protecting food crops against destructive pests.

Their study, which suggests a new use for one of the most important tropical crops in the world, appears in ACS” Journal of Agricultural and Food Chemistry, a bi-weekly publication.

Peas, beans and some other plant seeds contain proteins, called globulins, which ward off insects. Coffee beans contain large amounts of globulins, and Paulo Mazzafera and colleagues wondered whether those coffee proteins might also have an insecticidal effect. The high heat of roasting destroys globulins, so that they do not appear in brewed coffee.

Their tests against cowpea weevil larva, insects used as models for studying the insecticidal activity of proteins, showed that tiny amounts of the coffee proteins quickly killed up to half of the insects. In the future, scientists could insert genes for these insect-killing proteins into important food crops, such as grains, so that plants produce their own insecticides, the researchers suggest. The proteins appear harmless to people. (ANI)

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Coming soon: Drug that slows ageing process?

April 1, 2010 By Leave a Comment

London, Apr 1 (ANI): The secrets of a key gene that helps us to live longer and fight disease have been unlocked by University of Birmingham researchers.

With the breakthrough, boffins believe developing drugs that slow the ageing process could be a possibility, reports The Daily Express.

They reckon a drug based on the gene is a real possibility for cutting how quickly the body ages.

Dr Robin May, who led the research, said: “I think there is definite potential, within our lifetime, that we will be able to develop drugs to slow the ageing process based on this gene. Although stopping the ageing process may not happen, slowing it down is quite realistic.”

The research team found that higher levels of the gene – called DAF-16 – are directly linked with longer life.

In the study, boffins found that DAF-16 was strongly involved in determining ageing and average lifespan of laboratory worms.

Dr May said: “We wanted to find out how normal ageing is being governed by genes and what effect these genes have on other traits, such as immunity.

“To do that, we looked at a gene that we already knew to be involved in the ageing process, called DAF-16, to see how it may determine the different rates of ageing in different species. If you have more of that gene, you have got a better chance of living longer. Exposing the worms to a short burst of higher temperature, a quick bit of stress, increased the activity of this gene.

“It leads to the idea of what doesn’t kill you, does you good. If we have some moderate level of stress or challenge, that might be sufficient for us to live longer.”

The study has been published in the journal PLoS ONE. (ANI)

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DIY ability is in the genes

March 30, 2010 By Leave a Comment

London, Mar 30 (ANI): DIY (Do-It-Yourself) skills are in the genes, conclude scientists.

Psychologist Dr Glenn Wilson, Visiting Professor of Psychology, Gresham College, London, who led the experiment, said: ””Although there is not one specific DIY gene, spatial awareness is vital in understanding how shapes fit together and is therefore fundamental to DIY skills.

””Some people simply do not have the mental equipment necessary to manipulate shapes and will always struggle to complete DIY tasks successfully.””

To reach the conclusion and measure inherent DIY ability, researchers asked volunteers to complete specially designed multi-dimensional puzzles, reports The Telegraph.

The analyses revealed innate understanding of shapes and mechanics, an ability not subject to ””trial and error”” learning, the researchers said.

The study was conducted for Halifax Home Insurance. (ANI)

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Protein that tells the heart when it”s big enough identified

March 26, 2010 By Leave a Comment

Washington, Mar 26 (ANI): Researchers at Johns Hopkins have found the secret behind how the human heart and other organs automatically “right size” themselves— a protein discovered in fruit fly eyes.

The protein, named Kibra, is linked to a relay of chemical signals responsible for shaping and sizing tissue growth by coordinating control of cell proliferation and death.

The discovery could hold clues to controlling cancer.

In a series of experiments, the scientists manipulated Kibra”s role in a signalling network called the Hippo pathway, which consists of several proteins working together as a braking system.

Counterparts of the components in the Hippo pathway in flies are found in most animals, suggesting that this pathway may act as a “global regulator” of organ size control, said Dr. Duojia Pan.

“People have always been curious about what makes a hippopotamus grow so much bigger than a mouse. As well as how our two hands, which develop independently, get to very similar sizes. Our studies show that Kibra regulates Hippo, which keeps organs characteristically sized, preventing my heart or your liver from becoming as hefty as those befitting a large African amphibious mammal,” said Pan.

The researchers identified the gene they named Hippo in 2003, showing that an abnormal copy of it led to an unusually large eye in a developing fruit fly.

Pan said that the new experiments moved the investigation “slowly and methodically upstream” to find Hippo”s trigger, where “the key to size-control lies.”

Pan added that the Hippo-Kibra link could be a key to understanding and treating cancer because cancer is literally a disease of uncontrolled growth.

The Johns Hopkins and Florida State teams discovered Kibra by studying ovarian cells from adult flies and by using a gene-controlling technique called RNA interference (RNAi) to systematically turn off each of the approximately 14,000 genes in the fly genome, one at a time, in cultured fly cells.

They then analysed the function of Kibra in the developing fly larvae.

They found that the Hippo pathway was not active in the absence Kibra.

Further studies on human cells measured the activity of the Hippo pathway while manipulating human Kibra and showed that like its fruit fly counterpart, human Kibra acts as a tumour suppressor protein that regulates Hippo signalling.

“The discovery of Kibra moves us an important step closer to identifying the initial signal that triggers Hippo”s activation. We”re making progress along the Hippo pathway, heading toward the cell surface, and believe we will find that elusive signal en route,” said Pan.

The study has been published in Developmental Cell. (ANI)

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