Saturday, January 31, 2009

Safety device or just a must-have gizmo? The parent’s dilemma over pre-teen mobile

"The Tobi phone, unlike most mobiles, can block any numbers sending unwanted text messages"

It is the modern parental dilemma: at what age should you let your child have his or her first mobile phone? The answer could soon be in single figures with the introduction of a device aimed at “pre-teens”.
Samsung’s Tobi phone, released yesterday at a cost of between £70 and £80, is supposed to ease the minds of concerned parents with several safety features that will make it easier to call parents in an emergency and stop children receiving bullying text messages.
But it is also designed to appeal to primary school pupils, coming in “sweet pink” or “loyal blue” colours with a choice of on-screen themes based on animated characters and the ability to customise the back of the phone with a range of colourful designs. Samsung said that it would be marketing the device at parents but family groups doubt this.
“I’ve always thought that there is a potential market for phones with reduced functionality that can block images and phone numbers,” said John Carr, secretary of the Children’s Charities’ Coalition on Internet Safety. “What is not a good idea is increasing the pressure on parents through marketing to buy more branded goods. In essence, it will be the kids who pick up on it.”
Sue Palmer, author of Detoxing Childhood, which gives advice to parents on how to steer children through the problems of growing up, said: “We have a huge amount of child protection legislation which is protecting their bodies, but nobody is thinking about their minds.
“They’re being brainwashed and leeched on to think that the most important thing in the world is consumption, and their parents are now being brought into the act.”
Samsung defended the phone, saying that the advertising was “aimed squarely at parents” and that it had gained the support of some parents’ groups, such as the Children’s Safety Education Foundation. “A least it gives the parent a chance to sit down and think about the safety issue,” it said.
The Tobi, unlike most phones, can block senders of text messages, so a child can choose to stop receiving messages from a given phone number. Experts pointed out, however, that the phone also has Bluetooth technology, which gives an alternative way for someone to send malicious and offensive messages that cannot be blocked.
Mr Carr said: “Some horrible pictures, sometimes pornographic ones, of kids on the toilet or in the changing rooms, are swapped through Bluetooth.”
Mobile phone makers are finding it increasingly difficult to sell their products because consumer demand is slowing and because the vast majority of people already own a phone. Many pre-teen children are among the last who do not. Research by the regulator Ofcom last year suggested that 65 per cent of girls and 61 per cent of boys between the ages of 8 and 11 owned or had access to a mobile phone. But in the same age range, only 22 per cent of boys and 40 per cent of girls used a mobile phone every day.
Others pointed to health concerns. In 2005 Sir William Stewart, then chairman of the Health Protection Agency and the National Radiological Protection Board, recommended that 9 to 14-year-olds should make only short calls and that younger children should never use mobile phones.

Small talk The Mickey Mouse phone
A planned Disney service aimed at 8 to 14-year-olds was scrapped because of an “adverse retail environment”

“Child-safety” phone for four-year-olds programmed to call only four numbers.

Hello Kitty phone
Launched last summer in pink. Sanrio insisted that it was aimed at older women

Source: Times archives

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Unique stamps on world’s natural treasures on display

"Collector’s delight: A visitor takes a look at the stamps displayed at a thematic exhibition that opened in Chennai on Thursday."

CHENNAI: Every stamp displayed at the hall had a message to convey — protect the environment. Visitors to the thematic exhibition that opened in the city on Thursday got a glimpse into the natural treasures of the world and were educated about the need to preserve them.
Organised by South India Philatelists’ Association and Tamil Nadu Centre of ABK-AOTS Dosokai on the centre’s premises, to mark World Environment Day, the exhibition featured the collection of 11 philatelists under different themes.
Every inch of the wall was covered by a whopping number of over 8,000 stamps mounted in frames.
The collection of ABK-AOTS Dosokai’s chairman M.R.Ranganathan outlined the various causes of global warming, including deforestation and industrial pollution, and its consequences. The remedy and the global action to tackle the problem were also suggested through the stamps.
Gaurav Sethia, a school student, had an interesting collection on marine life in various countries such as Canada and Vietnam.
The stamps on rare species were accompanied by information on the marine life such as Gentoo Penguin is the fastest swimming bird.
Naturalist T.Murugavel’s collection on conservation of nature traced the history of mankind’s changing relationship with environment and degradation of natural resources. “I have added the adhesive of stamps on Koala bears printed in Australia as it also had the image of animal printed,” he said.
While butterflies dominated Norean Singh Nahar’s collection, others featured various kinds of pollution and flora and fauna.
South India Philatelists’ Association’s president G.Balakrishna Das said one of the participants had matched the stamps with photographs of the endangered species in his collection.
Earlier, inaugurating the exhibition, Principal Chief Postmaster General Indira Krishnakumar said the Postal Department created awareness of environmental conservation through release of stamps. Chief Conservator of Forests (Research) R.K.Ojha and Exnora International founder M.B.Nirmal participated in the programme.
The exhibition, which is open from 10 a.m. to 7 p.m. till Saturday, also has a dealers’ booth to facilitate purchase of stamps.

Three-day thematic stamp exhibition features some rare collections.

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Interested Or Deceptively Flirting? Observers Of First Dates Can Predict Outcome, Study Shows

"When it comes to assessing the romantic playing field -- who might be interested in whom -- men and women were shown to be equally good at gauging men's interest -- and equally bad at judging women's interest."

When it comes to assessing the romantic playing field -- who might be interested in whom -- men and women were shown to be equally good at gauging men's interest during an Indiana University study involving speed dating -- and equally bad at judging women's interest.
Researchers expected women to have a leg up in judging romantic interest, because theoretically they have more to lose from a bad relationship, but no such edge was found.
"The hardest-to-read women were being misperceived at a much higher rate than the hardest-to-read men. Those women were being flirtatious, but it turned out they weren't interested at all," said lead author Skyler Place, a doctoral student in IU's Department of Psychological and Brain Sciences working with cognitive science Professor Peter Todd. "Nobody could really read what these deceptive females were doing, including other women."
Place's study, published in the January issue of the journal Psychological Science, focused on the ability of observers to judge romantic interest between others because this ability has evolutionary benefits when it comes to finding a mate. Decisions that other people around us make, said Place, can influence or inform our own choices.
"So, if you walk into a room and there's 20 people you've never met before, being able to know which individuals might be available and which are clearly smitten by others can make you more efficient in finding your own romantic interest to pursue," he said.
For the study, 28 women and 26 men of college age watched video clips of couples interacting on speed dates. Speed dating is a popular commercial method for singles to meet a large number of individuals in one evening of successive brief one-on-one conversations. Each participant observed 24 videos, all with different men and women, and after each rated whether the man seemed interested in the woman and the woman in the man.
The speed dating sessions were all conducted in Germany while the observer ratings were all made by students in Indiana. Despite the language difference, observers were still able to judge men's romantic interest accurately using body language, tone of voice, eye contact, how often each dater spoke and other non-verbal cues.
"How people talk might convey more than what they say," Place said.
Observers did not have to see much of this non-verbal behavior. They were just as good at predicting the speed-dating couple's interest if they saw only 10 seconds of the date as they were if they saw 30 seconds. The researchers say this showed that observers, even with limited information, could make quick, accurate inferences using "thin slices" of behavior.
There was, however, great variability in how well observers could predict the interest of any particular speed-dater, ranging from 90 percent accuracy down to 10 percent. In five of the videos, 80 percent of the observers thought the women shown were interested when in fact they were not -- they were acting friendly even though they had no interest in the men.
Evolutionary theory, said Place, predicts a certain level of coyness or even deceptiveness in women because if a relationship is abandoned they may face greater costs, including pregnancy and child rearing. When choosing a mate, it is in a woman's best interest to get men to open up and talk honestly to give her a better idea of whether they would be good long-term partners.
"In a speed dating environment, you would expect to see these effects dramatically, with the women trying to get the men to be more straightforward, while they themselves remain more coy," Place said. "Though the pace is faster than a typical first date, the strategy remains the same."
Readers can see how successful they are at judging romantic interest by participating in a new online study that contains the same task as the one described here. To learn more or to participate in the 20-minute experiment being conducted by Place and his research colleagues, visit this site:
Co-authors include Peter M. Todd, Cognitive Science Program, in the College of Arts and Sciences at IU Bloomington; Lars Penke, University of Edinburgh in Scotland; and Jens B. Asendorpf, Humboldt University of Berlin.
Adapted from materials provided by Indiana University.
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Iraq sculpture honoring Bush shoe-thrower removed

“Children unwrap the sculpture of a shoe created as a monument to the shoes thrown by an Iraqi journalist …”

BAGHDAD – The director of an Iraqi orphanage says a sculpture honoring an Iraqi journalist who threw his shoes at former President George W. Bush has been removed.

Fatin al-Nassiri says Iraqi police told her the statue had to be removed from the orphanage in Tikrit because government property should not be used for something with a political bias.
She says the sofa-sized statue of a shoe was taken down on Saturday after being unveiled on Thursday.
Iraqi journalist Muntadhar al-Zeidi threw his shoes during a Dec. 14news conference in Baghdad. Throwing shoes at someone is a sign of extreme contempt in Arab culture.

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Friday, January 30, 2009

Low–cost LEDs May Slash Household Electric Bills Within Five Years

"Severn Bridge illuminated with white GaN LEDs."

A new way of making LEDs could see household lighting bills reduced by up to 75% within five years. Gallium Nitride (GaN), a man-made semiconductor used to make LEDs (light emitting diodes), emits brilliant light but uses very little electricity. Until now high production costs have made GaN lighting too expensive for wide spread use in homes and offices.
However the Cambridge University based Centre for Gallium Nitride has developed a new way of making GaN which could produce LEDs for a tenth of current prices.
GaN, grown in labs on expensive sapphire wafers since the 1990s, can now be grown on silicon wafers. This lower cost method could mean cheap mass produced LEDs become widely available for lighting homes and offices in the next five years.
Based on current results, GaN LED lights in every home and office could cut the proportion of UK electricity used for lights from 20% to 5%. That means we could close or not need to replace eight power stations.
A GaN LED can burn for 100,000 hours so, on average, it only needs replacing after 60 years. And, unlike currently available energy-saving bulbs GaN LEDs do not contain mercury so disposal is less damaging to the environment. GaN LEDs also have the advantage of turning on instantly and being dimmable.
Professor Colin Humphreys, lead scientist on the project said: “This could well be the holy grail in terms of providing our lighting needs for the future. We are very close to achieving highly efficient, low cost white LEDs that can take the place of both traditional and currently available low energy light bulbs. That won’t just be good news for the environment. It will also benefit consumers by cutting their electricity bills”.
GaN LEDs, used to illuminate landmarks like Buckingham Palace and the Severn Bridge, are also appearing in camera flashes, mobile phones, torches, bicycle lights and interior bus, train and plane lighting.
Parallel research is also being carried out into how GaN lights could mimic sunlight to help 3m people in the UK with Seasonal Affective Disorder (SAD).
Ultraviolet rays made from GaN lighting could also aid water purification and disease control in developing countries, identify the spread of cancer tumours and help fight hospital ‘super bugs’.
Funding was provided by the Engineering and Physical Sciences Research Council (EPSRC).
About GaN LEDs
A light-emitting diode (LED) is a semiconductor diode that emits light when charged with electricity. LEDs are used for display and lighting in a whole range of electrical and electronic products. Although GaN was first produced over 30 years ago, it is only in the last ten years that GaN lighting has started to enter real-world applications. Currently, the brilliant light produced by GaN LEDs is blue or green in colour. A phosphor coating is applied to the LED to transform this into a more practical white light.

GaN LEDs are currently grown on 2-inch sapphire. Manufacturers can get 9 times as many LEDs on a 6-inch silicon wafer than on a 2-inch sapphire wafer. In addition, edge effects are less, so the number of good LEDs is about 10 times higher. The processing costs for a 2-inch wafer are essentially the same as for a 6-inch wafer. A 6-inch silicon wafer is much cheaper to produce than a 2-inch sapphire wafer. Together these factors result in a cost reduction of about a factor of 10.

Possible Future Applications
1. Cancer surgery. Currently, it is very difficult to detect exactly where a tumour ends. As a result, patients undergoing cancer surgery have to be kept under anaesthetic while cells are taken away for laboratory tests to see whether or not they are healthy. This may need to happen several times during an operation, prolonging the procedure extensively. But in the future, patients could be given harmless drugs that attach themselves to cancer cells, which can be distinguished when a blue GaN LED is shone on them. The tumour’s edge will be revealed, quickly and unmistakably, to the surgeon.
2. Water purification. GaN may revolutionise drinking water provision in developing countries. If aluminium is added to GaN then deep ultra-violet light can be produced and this kills all viruses and bacteria, so fitting such a GaN LED to the inside of a water pipe will instantly eradicate diseases, as well as killing mosquito larvae and other harmful organisms.
3. Hospital-acquired infections. Shining a ultra-violet GaN torch beam could kill viruses and bacteria, boosting the fight against MRSA and C Difficile. Simply shining a GaN torch at a hospital wall or trolley, for example, could kill any ‘superbugs’ lurking there.
Adapted from materials provided by Engineering and Physical Sciences Research Council (EPSRC).
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High Hormone Levels In Women May Lead To Infidelity, Study Shows

"The researchers found that a woman's oestradiol level (sex hormone level) was positively associated with self-perceived physical attractiveness. Women with a higher oestradiol level also reported a greater likelihood of flirting, kissing and having a serious affair (but not a one-night stand) with a new partner."

Women with high levels of the sex hormone oestradiol may engage in opportunistic mating, according to a new study by psychology researchers at The University of Texas at Austin.
Doctoral candidate Kristina Durante and Assistant Professor of Psychology Norm Li published their findings in the Proceedings of the Royal Society of London: Biology Letters.

"The study offers further evidence that physiological mechanisms continue to play a major role in guiding women's sexual motivations and behavior," Durante said.
Durante and Li investigated the relationship between oestradiol, an ovarian hormone linked to fertility, and sexual motivation in a study of 52 female undergraduates not using contraception. Participants' ages ranged from 17 to 30 years old.

The researchers measured the participants' hormone levels at two points during each woman's ovulatory cycle and then asked them to rate their own physical attractiveness. Independent observers also rated the participants' physical attractiveness.
Participants also answered survey questions that measured their propensity to cheat on a partner.
The researchers found that a woman's oestradiol level was positively associated with self-perceived physical attractiveness. Women with a higher oestradiol level also reported a greater likelihood of flirting, kissing and having a serious affair (but not a one-night stand) with a new partner.
Oestradiol levels were negatively associated with a woman's satisfaction with her primary partner.
"Our findings show that highly fertile women are not easily satisfied by their long-term partners and are motivated to seek out more desirable partners," Durante explained. "However, that doesn't mean they're more likely to engage in casual sex. Instead, they adopt a strategy of serial monogamy".

Adapted from materials provided by University of Texas.
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Gene's Past Could Improve The Future Of Rice

"Purdue researcher Scott Jackson looks at an image of the rice genome. He traced the evolutionary history of rice in an effort to improve future varieties."

In an effort to improve rice varieties, a Purdue University researcher was part of a team that traced the evolutionary history of domesticated rice by using a process that focuses on one gene.
Scott A. Jackson, a professor of agronomy, said studying the gene that decides how many shoots will form on a rice plant allows researchers to better understand how the gene evolved over time through natural selection and human interaction. Understanding the variations could allow scientists to place genes from wild rice species into domesticated rice to create varieties with more branching, increased plant size or other favorable characteristics.
By comparing the domesticated plant to other wild rice species, they discovered a lot of genetic variation in rice over millions of years.
"This is a way to find these valuable genes in non-domesticated rice and bring them into cultivated rice," Jackson said. "We need to grow more food to feed the human population, and it needs to be done on less land and with less water. This could be the way to do that".
Jackson worked with Rod A. Wing of the University of Arizona and Mingsheng Chen of the Chinese Academy of Sciences in Beijing, and they were the corresponding authors for the study. Their findings are published in the Proceedings of the National Academy of Sciences online version this week.
The research team developed a tool to compare genes in different species of Oryza, of which domesticated rice is a species. Jackson said the comparisons showed how rice has changed from as far back as 14 million years ago. As rice adapted to climate changes and other natural circumstances, its genetic structure changed, keeping some genes and losing others.
About 10,000 years ago, humans began making their own genetic modifications, albeit unknowingly, by choosing plants that had favorable traits. As they stopped growing plants with unfavorable characteristics, genes responsible for those traits disappeared.
"Humans knew that if the seeds stayed on the plant, or it had a higher yield, they could save some of the seeds to plant next year," Jackson said. "That was unintentional breeding".
Those favorable genes are still around in wild rice species because they were valuable for plants in other climates or situations, he said.

Jackson was involved with earlier research that looked at cell structure in rice and also is studying the gene responsible for flowering in rice plants. Once those genes are better understood, scientists can match the best genes for particular climates to give growers better yields.
One example can be found in a variety of rice that has genes making it drought-resistant. Scientists could breed those genes into domesticated rice in Africa where water shortages can devastate crops.
National Science Foundation funding contributed to the research in addition to other grants.
Adapted from materials provided by Purdue University.
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Unique Archaeological Discovery In Balkan: World’s First Illyrian Trading Post Found

"The archaeologists found many artifacts including more than 30 Illyrian boats, fully-laden with Roman amphorae. One of the big questions is why none of the wine amphorae are whole. They are all in fragments."

There is jubilation at the Museum of Cultural History at the University of Oslo i Norway. Marina Prusac, Associate Professor in the department of archaeology, has just returned home after conducting excavations in the border area between Croatia and Bosnia-Herzegovina. In the course of several weeks of intense digging this autumn, her archaeological team found the very first traces of an Illyrian trading post that is more han two thousand years old. The Illyrians were an ancient people who lived by hunting, fishing and agriculture. They were known as warriors and pirates. Not only did they fight Greek colonists and Roman occupants, the various tribes also feuded among themselves. However, the archaeological finds show that the Illyrians also had peaceful trade connections with the Romans.
“The find is unique in a European perspective. We have concluded that Desilo, was the place is called, was an important trading post of great significance for contact between the Illyrians and the Romans,” Marina Prusac tells the research magazine Apollon at University of Oslo. Surprisingly large finds have been made in a short period of time. The archaeologists have discovered the ruins of a settlement, the remains of a harbour that probably functioned as a trading post, as well as many sunken boats, fully-laden with wine pitchers – so-called amphorae – from the first century B.C.
The archaeologist Adam Lindhagen, who has a PhD from the University of Lund and has specialised in Roman wine amphorae, says that this is the most important find of all time from the Illyrian areas.
“There is much to suggest that far more is hidden in the mud. We’ve only scraped the surface so far,” he points out.

Pirate theory
It all started in spring 2007 when Professor Snjezana Vasilj of the University of Mostar found 16 Illyrian boats in Desilo, fully-laden with Roman wine amphorae. The find was speedily interpreted as proof that the Illyrians were pirates and that the ships had been sunk by the Romans. Although the pirate theory received considerable attention from the press in many parts of Europe, Marina Prusac and Adam Lindhagen did not believe this interpretation. “There certainly were pirate activities along the coast, but we thought it rather odd that the pirates were so far inland and so near the important Roman colony of Narona. In our opinion Desilo might have been a trading centre”. Desilo is located 20 kilometres from the coast on an alluvial plain by the River Neretva. The river is the only traffic artery along the entire Croatian coast that runs into the Balkan mountains. It is broad and free-flowing for the first 30 kilometres or so, after which its course becomes narrow. Near Desilo there are also ancient traffic arteries on land in the direction of both Narona, which was first a Greek trading post and then a Roman colony, and the Illyrian settlement of “Daorson” – the present-day Osanic.“Desilo is situated at the innermost point of a quiet bay where it was natural to transfer goods to smaller boats, so the place is perfect for an inner trading harbour. We knew that if we found a harbour it would represent a rare example of a meeting point in this impenetrable landscape. And we found it!” a delighted Ms Prusac tells us.

The harbour
Over the past two thousand years the river has repeatedly changed its bed in the delta. The archaeologists found the remains of the Illyrian trading post under several metres of mud and ooze when the land-owner put his excavator at their disposal. It appears that parts of the wall that stuck up from the mud by the water’s edge may have functioned as one of the many quays at the trading post. The wall is 20 metres long and 60 centimetres wide, and is built as a polygonal structure. “The wall was solid and stable. The other side was not so well constructed and most likely functioned as a dam. There were a number of mooring holes placed at the same height on the wall, almost like a horizontal band”. And as if this was not enough, the archaeologists from the University of Oslo also discovered that there were at least twice as many boats as those that had already been registered. The boats, which the Romans called Lembi, were well known for their fast manoeuvrability. The many pieces of pottery found indicate that this was a major trading post. And last but not least: about a hundred metres from the harbour site they found an Illyrian settlement. Moreover, in collaboration with the land-owner and along with master’s degree student Jo-Simon Frøshaug Stokke, the recently graduated archaeologists Lene Os Johannessen and Ole Christian Aslaksen discovered terrace formations in the mountainside. “This find can only be interpreted as indicating the presence of a settlement that presumably existed for several hundred years or even longer before the trade between the Illyrians and the Romans started”. Some graves – older than the other finds – were previously discovered close to the settlement. A number of individual finds have also been made in the area: anchor parts, lance tips and fibula, and metal buckles for fastening clothes. “Thanks to the clay and the fresh water the objects are surprisingly well preserved. Salt water would have destroyed the wood”.

On the sea bed, together with the boats, archaeologists from Moster found hundreds of pieces of wine amphorae and as many as 700 lids from these pitchers. “Imports from the Roman colony Narona must therefore have been far more extensive than we previously thought,” Adam Lindhagen points out.
He has analyzed the pottery to find out where the amphorae came from. He can now say that they were exclusively produced along the Dalmatian coast – from where wine was exported to the entire Roman Empire.
“In exchange for wine the Romans may have bought salt, metal, leather and slaves. The price could have been the same as in the north. According to Julius Caesar (100-44 B.C.), the Gauls were happy to swap a slave for a 25-litre amphora of wine”. While Professor Vasilj was of the view that all the boats were sunk at the same time in a Roman campaign against Illyrian pirates, the Norwegian archaeologists have found indications that the boats were sunk over a period of almost a hundred years. Their evidence is based on the dating of the wine amphorae.

One of the big questions is why none of the amphorae are whole. They are all in fragments. “We don’t know why the boats were sunk and the pitchers destroyed. It’s absurd to think that the Romans sank almost a thousand amphorae containing their own wine. The amphorae may have been dumped when they’d been emptied. But animal bones, horse teeth, Illyrian pottery and weapons like axes and spear tips have also been found in the sea. So it’s possible that they made ritual offerings to the sea – a well-known phenomenon in Scandinavia during the Iron Age. If we can confirm that this is the case, then this is the first example we have heard of from the Illyrian area.”

Cultural identity
Archaeological research on the Illyrians was used politically as the culture-historical glue of the various groups in the former Yugoslavia. Today the focus is more on the differences between the Illyrian peoples. “The neutral term ‘Illyrian’ was applied to all ethnic groups in the former Yugoslavia. The Illyrians have been described as warriors, and little focus has been placed on peaceful connections between the Illyrians and the Romans. So it’s important to be able to reveal peaceful relations and to show that the Illyrians had come a long way in their cultural contact with other nations, at the same time as there were great differences between the Illyrian tribes. Our discovery is therefore important for understanding cultural identities in the Balkans in ancient times,” Marina Prusac tells us.

Adapted from materials provided by University of Oslo.
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How Ebola Virus Avoids The Immune System

"Scanning electron microscope image of Ebola virions (spaghetti-like filaments) on the surface of a tetherin-expressing cell (center)."

Researchers at the University of Pennsylvania School of Medicine have likely found one reason why the Ebola virus is such a powerful, deadly, and effective virus. Using a cell culture model for Ebola virus infection, they have discovered that the virus disables a cellular protein called tetherin that normally can block the spread of virus from cell to cell.

“Tetherin represents a new class of cellular factors that possess a very different means of inhibiting viral replication,” says study author Paul Bates, PhD, Associate Professor of Microbiology at the University of Pennsylvania School of Medicine. “Tetherin is the first example of a protein that affects the virus replication cycle after the virus is fully made and prevents the virus from being able to go off and infect the next cell.” These findings appear online this week in the Proceedings of the National Academy of Sciences.
When a cell is infected with a virus like Ebola, which is deadly to 90 percent of people infected, the cell is pirated by the virus and turned into a production factory that makes massive quantities on new virions. These virions are then released from that cell to infect other cells and promote the spreading infection.
Tetherin is one of the immune system's responses to a viral infection. If working properly, tetherin stops the infected cell from releasing the newly made virus, thus shutting down spread to other cells. However, this study shows that the Ebola virus has developed a way to disable tetherin, thus blocking the body's response and allowing the virus to spread.
“This information gives us a new way to study how tetherin works,” says Bates. "Binding of a protein produced by Ebola to tetherin apparently inactivates this cellular factor. Understanding how the Ebola protein blocks the activity of tetherin may facilitate the design of therapeutics to inhibit this interaction, allowing the cell's natural defense systems to slow down viral replication and give the animal or person a chance to mount an effective antiviral response and recover.”
Previous research had found that tetherin plays a role in the immune system's response to HIV-1, a retrovirus, and that tetherin is also disabled by HIV. These new studies reveal that human cells also use this defense against other types of viruses, such as Ebola, that are not closely related to HIV-1. “Because we see such broad classes of viruses that are affected by tetherin, it's possible that all enveloped viruses are targets of this antiviral system,” says Bates. “If so, then understanding how tetherin works and how viruses escape from the effect of tetherin will be very important.”
Rachel L. Kaletsky, Joseph R. Francica and Caroline Agrawal-Gamse of the University of Pennsylvania School of Medicine are co-authors of this study. This work was funded by the Public Health Service Grants and the Philip Morris External Research Foundation.
Adapted from materials provided by University of Pennsylvania School of Medicine.
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