Europe against GMO crops! Please, sign the Avaaz petition! I already did.
It's us who decide, not Monsanto!!!

Tuesday, 29 April 2008

New promising treatment of tumors saves a girl

A lovely story of new and smart treatment to cancer that saved a little girl combining known medicines in unexpected way. Hopefully this will give a new boost to cancer treatments and pharmacists companies will back it. The article is from NY Times.
Melanie was 9 months old when her parents faced an agonizing decision. She had already had two operations for a malignant brain tumor, and doctors could not be sure they had removed all the cancer. She needed more treatment, but standard chemotherapy offered little hope in exchange for its harsh side effects.

Doctors at the Dana-Farber Cancer Institute in Boston offered another option, an experimental treatment. To qualify, a child had to have a progressive cancer, and it had to be terminal. The McDaniels took a gamble and a leap of faith, and signed Melanie up.

Recently, Mr. McDaniel sent me an e-mail message. “Melanie is now 7 years old, attending first grade, and doing very well,” he wrote. “The doctors told us last year that they do not see any residual tumor in her brain. Their original diagnosis was that her tumor had no known cure.”

Dr. Folkman founded a branch of research based on the theory that tumors need a blood supply in order to grow and can stimulate the formation of new blood vessels — angiogenesis — to feed themselves. If angiogenesis could be stopped, he reasoned, it might be possible to starve tumors. His work ultimately led to useful treatments but took years to gain acceptance in a field that was focused on attacking cancer cells directly.

Melanie McDaniel became one of 20 children with advanced cancer who were enrolled in a study that used drugs strictly to fight angiogenesis. The drugs included two standard anticancer medicines, but in small doses meant to stop blood vessels from forming, not the much bigger amounts needed to poison tumor cells.

The children also took two other drugs that had been found to block angiogenesis. One was Celebrex, usually given for pain and inflammation. The other was thalidomide, notorious for causing stunted limbs and other birth defects when pregnant women took it in the 1960s — damage, it was later learned, that the drug inflicted by halting the growth of blood vessels in the fetus.

Melanie and the other children were given small doses of medicine by mouth every day, instead of big doses intravenously every few weeks. The idea was that continuous treatment might keep blood vessel growth in check, whereas the usual schedule of therapy every few weeks could give new vessels a chance to sprout between doses. Doctors also hoped that the small doses would minimize side effects. The approach is called metronomic, low-dose or antiangiogenic chemotherapy.

“Our goal was to see whether we could keep the kids alive for an additional six months,” said Dr. Mark W. Kieran, Dana-Farber’s director of pediatric medical neuro-oncology.

The study was meant to test the feasibility of using the drugs for 26 weeks. But by the 26th week, seven children were doing so well that their parents refused to give up the drugs.

The McDaniels kept Melanie on the drugs for a year and a half. Then, she was monitored closely with M.R.I. scans.

Finally, last year, her doctors said there were no traces of the tumor left.

The next step is a larger study. One is already under way, involving 160 children at 12 medical centers, with eight categories of cancer.

“As much as we’re excited about how good she’s doing, there’s that much fear of it coming back,” said her mother, Amy McDaniel. “It’s always in your mind.

“We need the science to keep going. We need to be armed and ready if it does return.” source

Friday, 25 April 2008

New type of computers

A cool video about new type of computers, unfortunately made by M$

Wednesday, 23 April 2008

Colon cancer-new discoveries

Easily Overlooked Lesions Tied to Colon Cancer

March 5, 2008

An easily overlooked type of abnormality in the colon is the most likely type to turn cancerous, and is more common in this country than previously thought, researchers are reporting.

The findings come from a study of colonoscopy, in which a camera-tipped tube is used to examine the lining of the intestine. Generally, doctors search for polyps, abnormal growths that stick out from the lining and can turn into cancer. But another type of growth is much more dangerous, and harder to see because it is flat or depressed and similar in color to healthy tissue.

Japanese researchers became concerned about these flat lesions in the 1980s and ’90s, but studies here had mixed results and American doctors tended to think that flat growths were less common and less dangerous in the United States.

The new study, to be published Wednesday in the Journal of the American Medical Association, suggests otherwise.

Some doctors in this country were already alert to flat lesions, but the findings will pose a challenge to others, because it takes a trained and vigilant eye to see the growths and special techniques to remove them. The results also mean it is especially important that patients take the harsh laxatives that many dread in advance of the test. The flat lesions, hard to find even under the best conditions, will be impossible to see if any waste is left in the bowel.

Colon cancer is the second-leading cause of cancer death in the United States, after lung cancer, with about 154,000 new cases detected and 52,000 deaths a year. It is one of the few cancers that is totally preventable if precancerous growths are found and removed; it can also be cured with surgery alone if found early enough.

People who have just had a colonoscopy should not rush to schedule another one just to look for the flat growths, doctors said.

People should see a doctor any time they have persisting symptoms that could indicate colon cancer, like rectal bleeding or a change in bowel habits — no matter how recently they had a colonoscopy. The test is highly reliable, but not perfect, doctors say.

The study, of 1,819 military veterans, mostly men, found that 9.35 percent had flat lesions, and those lesions were five times as likely as polyps to contain cancerous or precancerous tissue. Depressed or indented lesions were the least common but the most risky. Together, the flat or depressed lesions accounted for only 15 percent of the potentially cancerous growths found in the study, but were involved in half of the cancers. Once the doctors spotted the flat lesions, they sprayed a bluish dye on them to see their outlines better and remove them completely.

The first author of the study, Dr. Roy M. Soetikno of the Veterans Affairs Palo Alto Health Care System said, “The message for doctors is, Here is a large amount of data showing that these precursors of cancer, always believed to be a Japanese disease, are actually a disease here, and are important, because they are much more likely to be cancerous, and doctors need to spend the time to provide quality colonoscopy.”

The message to patients, Dr. Soetikno said, is that when preparing for colonoscopy, they must follow instructions to the letter and take the hated laxatives to make sure their bowels are empty so that doctors can see the lining.

The quality of colonoscopy has become a delicate issue, because an article in The New England Journal of Medicine in December 2006 found that some doctors were 10 times better than others at finding precancerous polyps. A major factor in their success was taking enough time to examine the colon thoroughly, as opposed to rushing through the procedure. Doctors who miss polyps would almost certainly miss flat lesions as well because they are harder to see. The new study underscores the need for careful examinations, because the flat lesions are more dangerous.

The study also raises doubts about whether “virtual colonoscopy,” performed by a CT scanner, will ever be able to take the place of the colonoscope inserted into the rectum, as many patients had hoped. The problem is that CT scans use X-rays to reveal shapes, and find polyps because they stick out. Flat lesions are unlikely to show up in such scans.

Studies show that from 0.3 percent to 0.9 percent of patients develop colon cancers within just a few years of having a colonoscopy and polyp removal — exactly what the procedure is supposed to prevent. Some doctors think that flat lesions, missed entirely during the colonoscopy or not fully removed, may account for some of these apparent failures.
source

My comment: As unpleasant as might sound, colonoscopy is essential in preventing this kind of cancer. I'm not sure how spread is this cancer outside USA, at least, here, in Bulgaria, I don't here too much of it, but I know it's lethal and it's preventable. That's all I need to make sure I have all the information about it.

Friday, 18 April 2008

Solar energy in our hands

Turning Glare Into Watts

Mr. Boucher was battling clouds, timing the operations of his power plant to get the most out of patchy sunshine. It is a skill that may soon be in greater demand, for the world appears to be on the verge of a boom in a little-known but promising type of solar power.

It is not the kind that features shiny panels bolted to the roofs of houses. This type involves covering acres of desert with mirrors that focus intense sunlight on a fluid, heating it enough to make steam. The steam turns a turbine and generates electricity.

The technology is not new, but it is suddenly in high demand. As prices rise for fossil fuels and worries grow about their contribution to global warming, solar thermal plants are being viewed as a renewable power source with huge potential.

After a decade of no activity, two prototype solar thermal plants were recently opened in the United States, with a capacity that could power several big hotels, neon included, on the Las Vegas Strip, about 20 miles north of here. Another 10 power plants are in advanced planning in California, Arizona and Nevada.

On sunny afternoons, those 10 plants would produce as much electricity as three nuclear reactors, but they can be built in as little as two years, compared with a decade or longer for a nuclear plant. Some of the new plants will feature systems that allow them to store heat and generate electricity for hours after sunset.

Aside from the ones in the United States, eight plants are under construction in Spain, Algeria and Morocco. Another nine projects are in various stages of planning in those countries as well as Israel, Mexico, China, South Africa and Egypt, according to a count kept by Frederick H. Morse, formerly in charge of solar energy at the Energy Department and now a consultant.

In Phoenix on Feb. 21, the Arizona Public Service unit of Pinnacle West announced plans for a large plant to be built by a Spanish company, Abengoa, and finished in 2011. That one will store heat so that it can continue to produce power for up to six hours after sunset.

The newest solar-thermal technology involves building a “power tower,” a tall structure flanked by thousands of mirrors, each of which pivots to focus light on the tower, heating fluid. That design can work even in places with weaker sunlight than a desert.

One of the big advantages of these plants is that they can be built with the capacity to store heat in what amounts to a giant Thermos. Experts say that will smooth production and make it easier to integrate the plants into the electrical grid.

If large numbers of plants are built, they will eventually pose some problems, even in the desert. They could take up immense amounts of land and damage the environment. Already, building a plant in California requires hiring a licensed tortoise wrangler to capture and relocate endangered desert tortoises.

Outside, row after row of U-shaped mirrors, covering nearly a square mile, stretched across the desert. In the center of each U, where the force of the sun was magnified 70 times, ran a pipe painted black, and inside it flowed oil that warmed to hundreds of degrees as it collected the heat needed to run a generator.source

My comment: It was high time to see some growth in solar plants. What bothers me is that technology doesn't grow with them. We expand in volume (ok, surface if we have to be more precise),but not in quality and innovations.

But well, better than nothing.

Monday, 14 April 2008

Exoskeletons, Petar Hamilton, everyone!

In this edition:


Exoskeleton shows running, not walking, best on Moon

MIT researcher Christopher Carr demonstrates walking and running wearing an exoskeleton that simulates a pressurised spacesuit (Video: David Shiga/Sandrine Ceurstemont)
A fibreglass exoskeleton helps simulate what it is like to walk on the Moon in a pressurised space suit (Image: David Shiga)
A fibreglass exoskeleton helps simulate what it is like to walk on the Moon in a pressurised space suit (Image: David Shiga)

Future astronauts should run, not walk, across the lunar surface to conserve energy, new laboratory tests suggest. The tests were done using an MIT-built exoskeleton that mimics the experience of moving around in a spacesuit.

Astronauts move differently on the Moon than on Earth because of the Moon's weaker gravity and the constricting properties of spacesuits. So Christopher Carr and Dava Newman of MIT in Cambridge, US, have devised a way to simulate that motion in the hopes of designing better spacesuits and planning future lunar activities.

They reasoned that walking inside a pressurised spacesuit is like wearing an air-filled balloon. Like balloons, the suits resist bending and tend to want to return to their original shape, making it harder for Moon-walking astronauts to bend their legs at the knee.

So the researchers built an exoskeleton to simulate this, based on a design by another MIT scientist, Hugh Herr, who creates devices to aid people with disabilities. The exoskeleton consists of fibreglass rods that run the length of the wearer's legs and clip into modified cycling shoes.

Like a pressurised spacesuit, the exoskeleton resists bending at the knee, applying a force that tends to straighten the leg again. Intriguingly, this spring-like property makes running more efficient than walking for an exoskeleton-clad person. That's because the extra springiness helps to recover a higher percentage of the energy put into each stride while running.

The researchers believe that the same effect makes running the more efficient choice for space-suited astronauts on the Moon, something they had already suspected from watching videos of Apollo lunar missions. "The spacesuit is storing energy," Carr says, explaining that the air-filled spacesuit legs act like springs.

For the full effect of Moon walking, the laboratory Carr and Newman used for their research can also simulate lunar gravity. By tying the exoskeleton-clad person to a cord that runs up to the ceiling and is attached to a spring, the researchers can adjust the downward force to match the Moon's surface gravity, which is one-sixth that of Earth.

Journal reference: Acta Astronautica (DOI: 10.1016/j.actaastro.2007.11.007). source

My comment: What I find more interesting than running vs. walking is the exoskeleton they used for the simulation and what it could develop in . Peter Hamilton, anyone?

Silicon womb' to begin fertility trials

The 'silicon womb' compared to conventional IVF (Image: Anecova)
The 'silicon womb' compared to conventional IVF (Image: Anecova)
Detail of the silicon womb (Image: Anecova)
Detail of the silicon womb (Image: Anecova)

Trials of a "silicon womb" that holds test-tube embryos inside the womb to expose them to more natural conditions will shortly begin in the UK. Researchers say the new device may produce better quality embryos and reduce the need to harvest so many eggs from infertile women.

In standard IVF, eggs harvested from a woman are fertilised in the lab and allowed to develop in an incubator for 2 to 5 days. The healthiest embryos are chosen to be transferred into the uterus.

The new device allows embryos created in the lab to be incubated inside a perforated silicon container inserted into a woman's own womb. After a few days, the capsule is recovered and some embryos are selected for implantation in the womb (see image, top right)

Embryos incubated in the lab must have their growth medium changed every few hours to provide new nutrients and get rid of waste. The new device provides a more natural environment.

The silicon capsule is about 5 millimetres long and less than a millimetre wide. Its walls are perforated with 360 holes, each around 40 microns across. After embryos have been loaded inside, the ends are sealed and the container is connected to a flexible wire that holds the device inside the uterus (see image, lower right). A thread trails through the cervix to allow it to be recovered later on.

The device was developed by Swiss company Anecova, which has so far only conducted a small trial in Belgium.

Results were encouraging but not conclusive, says Simon Fishel, who is leading the first large-scale trial, at UK fertility group CARE Fertility, in Nottingham, UK.

Fishel says the new device could take some of the guesswork out of incubating embryos. "We don't really know the full ambient conditions of the reproductive tract," he told New Scientist. "It is also a dynamic environment that changes constantly, and we can't replicate that."

He believes embryos grown in the device will be more resilient, meaning fewer eggs may need to be harvested from women to achieve a successful pregnancy. Most IVF techniques require the woman to stimulate egg production by taking hormones, which can sometimes cause dangerous side-effects. source

My comment: I think every development in that area is cause for applauses. As a woman, I can't but hate everyone that wants to put something between my legs for other reason than the obvious, so this looks like a good way to reduce the over-all misery. And it improves the chance of getting a healthy baby, which is great.


Thursday, 10 April 2008

Arctic Seed Vault Is a Fort Knox of Food

Near Arctic, Seed Vault Is a Fort Knox of Food


Published: February 29, 2008

LONGYEARBYEN, Norway — With plant species disappearing at an alarming rate, scientists and governments are creating a global network of plant banks to store seeds and sprouts, precious genetic resources that may be needed for man to adapt the world’s food supply to climate change.

This week, the flagship of that effort, the Global Seed Vault near here, received its first seeds, millions of them. Bored into the middle of a frozen Arctic mountain topped with snow, the vault’s goal is to store and protect samples of every type of seed from every seed collection in the world.

As of Thursday, thousands of neatly stacked and labeled gray boxes of seeds — peas from Nigeria, corn from Mexico — reside in this glazed cavelike structure, forming a sort of backup hard drive, in case natural disasters or human errors erase the seeds from the outside world.

Descending almost 500 feet under the permafrost, the entrance tunnel to the seed vault is designed to withstand bomb blasts and earthquakes. An automated digital monitoring system controls temperature and provides security akin to a missile silo or Fort Knox. No one person has all the codes for entrance.

The Global Vault is part of a broader effort to gather and systematize information about plants and their genes, which climate change experts say may indeed prove more valuable than gold. In Leuven, Belgium, scientists are scouring the world for banana samples and preserving their shoots in liquid nitrogen before they become extinct. A similar effort is under way in France on coffee plants. A number of plants, most from the tropics, do not produce seeds that can be stored.

For years, a hodgepodge network of seed banks has been amassing seed and shoot collections in a haphazard manner. Labs in Mexico banked corn species. Those in Nigeria banked cassava. Now these scattershot efforts are being urgently consolidated and systematized, in part because of better technology to preserve plant genes and in part because of the rising alarm about climate change and its impact on world food production.

This week the urgency of the problem was underscored as wheat prices rose to record highs and wheat stores dropped to the lowest level in 35 years. A series of droughts and new diseases cut wheat production in many parts of the world. “The erosion of plants’ genetic resources is really going fast,” said Dr. Rony Swennen, head of the division of crop biotechnology at the Catholic University of Leuven in Belgium, who has preserved half of the world’s 1,200 banana types. “We’re at a critical moment and if we don’t act fast, we’re going to lose a lot of plants that we may need.”

The United Nations International Treaty on Plant Genetic Resources, ratified in 2004, created a formal global network for banking and sharing seeds, as well as for studying their genetic traits. Last year, its database received thousands of new seeds.

A system of plant banks could be crucial in responding to climate crises since it could identify genetic material and plant strains better able to cope with a changed environment.

Here at the Global Vault, hundreds of gray boxes containing seeds from places ranging from Syria to Mexico were moved this week into a freezing vault to be placed in suspended animation. They harbor a vast range of qualities, like the ability to withstand drier, warmer climate.

Climate change is expected to bring new weather stresses, as well as new plant pests into agricultural regions. Heat-trapping carbon dioxide emissions will produce not just global warming but an increase in extreme weather events, like floods and droughts, the Intergovernmental Panel on Climate Change concluded.

Already three-quarters of biodiversity in crops has been lost in the last century, according to the United Nations Food and Agriculture Organization. Eighty percent of maize types that existed in the 1930s are gone, for example. In the United States, 94 percent of peas are no longer grown.

Seed banks have operated for decades, but many are based in agricultural areas and few are as high-tech or secure as the Global Seed Vault. They have often been regarded as resources for hobbyists, scientists, farmers and others rather than as a tool for human survival.

Their importance and vulnerability have become apparent in recent years. Seed banks in Afghanistan and Iraq were destroyed during conflicts in those nations, by looters who were after the plastic containers that held the seeds. In the Philippines, a typhoon bore through the wall of a seed bank, destroying numerous samples.

Seeds must be stored at minus 20 degrees Celsius, that is, well below freezing, and plants that rely on cryopreservation must be far colder.

Underground near Longyearbyen, just 600 miles from the North Pole, the seeds will stay frozen despite power failures. The Global Crop Diversity trust is also financing research into methods for storing genetic material from plants like bananas and coconuts that cannot be stored as seed.

The vault was built by Norway, and its operations are financed by government and private donations, including $20 million from Britain, $12 million from Australia, $11 million from Germany and $6.5 million from the United States. The effort to preserve a wide variety of plant genes in banks is particularly urgent because many farms now grow just one or two crops, with very high efficiency. Like purebred dogs perfectly tailored to their task, they are particularly vulnerable to both pests and climate change.

Scientists are also working to learn more about the skills encoded in the genes of each banked seed — crucial knowledge that is often not recorded. Ultimately, plant breeders will be able to consult a global database to find seeds with genes suitable for the particular climate challenge confronting a region — for instance, a corn with a stalk that resists storm winds or a wheat that needs less frequent water.

Scientists at Cornell University recently borrowed a gene from a South American potato to make potatoes that resisted the late blight fungus, a devastating disease that caused the Irish potato famine. source

My comment:Awesome! Mostly because it's on European soil :) But not only. Protecting the genetic base of the Earth is really important, especially with all the modifying stuff.

Monday, 7 April 2008

Mini solar system and No to the twins

Smaller Version of the Solar System Is Discovered

February 15, 2008

Astronomers said Wednesday that they had found a miniature version of our own solar system 5,000 light-years across the galaxy — the first planetary system that really looks like our own, with outer giant planets and room for smaller inner planets.

Their results are being published Friday in the journal Science. The discovery, they said, means that our solar system may be more typical of planetary systems across the universe than had been thought.

In the newly discovered system, a planet about two-thirds of the mass of Jupiter and another about 90 percent of the mass of Saturn are orbiting a reddish star at about half the distances that Jupiter and Saturn circle our own Sun. The star is about half the mass of the Sun.

Since 1995, around 250 planets outside the solar system, or exoplanets, have been discovered. But few of them are in systems that even faintly resemble our own. In many cases, giant Jupiter-like planets are whizzing around in orbits smaller than that of Mercury. But are these typical of the universe?

Almost all of those planets were discovered by the so-called wobble method, in which astronomers measure the gravitational tug of planets on their parent star as they whir around it. This technique is most sensitive to massive planets close to their stars.

The new discovery was made by a different technique that favors planets more distant from their star. It is based on a trick of Einsteinian gravity called microlensing. If, in the ceaseless shifting of the stars, two of them should become almost perfectly aligned with Earth, the gravity of the nearer star can bend and magnify the light from the more distant one, causing it to get much brighter for a few days.

If the alignment is perfect, any big planets attending the nearer star will get into the act, adding their own little boosts to the more distant starlight.

That is exactly what started happening on March 28, 2006, when a star 5,000 light-years away in the constellation Scorpius began to pass in front of one 21,000 light-years more distant, causing it to flash. That was picked up by the Optical Gravitational Lensing Experiment, or Ogle, a worldwide collaboration of observers who keep watch for such events.

Ogle in turn immediately issued a worldwide call for continuous observations of what is now officially known as OGLE-2006-BLG-109. The next 10 days, as Andrew P. Gould, a professor of mathematical and physical sciences at Ohio State said, were “extremely frenetic.”

Somewhat to the experimenters’ surprise, by clever manipulation they were able to dig out of the data not just the masses of the interloper star and its two planets, but also rough approximations of their orbits, confirming the similarity to our own system. David P. Bennett, an assistant professor of astrophysics at the University of Notre Dame, said, “This event has taught us that we were able to learn more about these planets than we thought possible.”

As a result, microlensing is poised to become a major new tool in the planet hunter’s arsenal, “a new flavor of the month,” Dr. Seager said.

Only six planets, including the new ones, have been discovered by microlensing so far, and the Scorpius event being reported Friday is the first in which the alignment of the stars was close enough for astronomers to detect more than one planet at once. Their success at doing just that on their first try bodes well for the future, astronomers say. source

My comment: Well ,slowly but surely we're getting there. And if that black hole fails to eat the Earth, we're going to find them :) Many speculations have been done about what will happen with Earth and its religions when we find out we're not alone and they are other sentient beings in our Universe. I won't speculate. I simply know that the new perspective always changes the old beliefs. Of course, for the moment we just discover new solar systems, new planets. We're far from any signs of life. But then if there's possibility, there will be an opportunity.

Lowering Odds of Multiple Births


Published: February 19, 2008

In the complex, expensive and emotionally charged world of fertility treatment, doctors are sounding a call to arms to reverse the soaring rate of multiple births.

The doctors are responding to an unintended consequence of the success of in vitro fertilization — that it is often too successful. Since 1980, when the technique became available in the United States, the rate of twins in all births has climbed 70 percent, to 3.2 percent of births in 2004.

Much of the increase, experts say, is a result of in vitro treatment. The rate of triplets and higher-order multiples increased even more from 1980 to 1998. It is not that twins or triplets are undesirable, doctors say. But multiple pregnancies often lead to risky preterm births and other complications. With that in mind, fertility centers are trying to lower the odds of such pregnancies, even at a cost of slightly lower success rates.

In I.V.F., a woman is given ovulation-induction hormones to produce multiple eggs, which are retrieved, fertilized with her partner’s sperm and transferred back to her uterus. The more embryos transferred, the higher the likelihood of multiples.

To achieve the goal of a single healthy baby, clinics are focusing on transferring fewer embryos and on developing more sophisticated ways to identify the healthiest embryos with the greatest chance of success.

“We have been getting better at I.V.F. over the years, and as success rates go up, the number we transfer has to go down accordingly,” said Dr. Judy E. Stern, director of the human embryology and andrology lab at the Dartmouth-Hitchcock Medical Center in Lebanon, N.H. “Where three embryos used to work and give you mostly singletons, now we transfer two, because we’re making better embryos and more of them implant.”

The number of I.V.F. cycles in which four or more embryos were transferred has dropped sharply, to 21 percent in 2004 from 62 percent in 1996. Although the efforts have substantially lowered the rates of triplets born through in vitro fertilization, they have not made a dent in the twin rate. That is because many doctors and patients are reluctant to take the final step to ensure a single birth, a process called S.E.T., for single embryo transfer. From 1996 to 2004, the rate of such procedures rose modestly, to 8 percent from 6 percent.

The American Society of Reproductive Medicine now recommends that women younger than 35 with a good prognosis have just one embryo transferred. Women under 35 make up 44 percent of I.V.F. cycles.

In women older than 37, who have a higher incidence of embryos with chromosomal defects, three to five embryos are still recommended, depending on the woman’s age.

The main obstacle to single embryo transfer is its lower success rate. Some experts ask women to agree to two cycles, first transferring one fresh embryo while freezing the others. If the first transfer fails, doctors transfer a single frozen embryo, a much less costly and onerous procedure. That approach yields similar success rates to transferring two at once while drastically reducing twin rates.

With momentum building to transfer just one or two embryos, clinics focus on choosing the embryo most likely to succeed. Selecting embryos has traditionally been based on a visual examination of their morphology — shape, number of divisions and other physical factors. But morphology does not tell all, and many embryos that look great under the microscope have undetected chromosomal abnormalities like missing or extra chromosomes, called aneuploidy.

One method used to weed out unhealthy embryos is to leave the embryos in a Petri dish for five days, two more than usual, to allow more time for hidden chromosomal abnormalities to show up.

Other researchers are looking at the traits of women at high risk of having multiples. In research presented at the reproductive society’s annual meeting last October, Dr. Stern linked a higher number of oocytes, or eggs retrieved from ovaries, with higher rates of single and multiple pregnancies.

“This will change our practice,” she said. “If more oocytes are retrieved, we’ll want to transfer fewer embryos.”

Other experts are turning to preimplantation genetic screening to cull embryos without aneuploidy. The screening is used to select healthy embryos in families with histories of genetic diseases. Because one or two cells have to be removed for analysis, there is some concern that the process can damage embryos, lowering pregnancy rates.

Another screening, comparative genomic hybridization, can assess all 23 pairs of chromosomes, providing an 80 percent chance of a healthy embryo and a 60 percent chance of a live birth, says Dr. Geoffrey Sher, executive medical director of the Sher Institutes of Reproductive Medicine, a nationwide group of fertility centers.

But Dr. Sher, whose lab performs this procedure, has encountered the same obstacles as others. He has a very high twin rate, hovering around 60 percent, because although the technique yields a higher success rate, women are refusing to have just one embryo transferred.

Many women in fertility treatment say that they simply do not view having twins as a risky situation and that they are willing, if not eager, to have them to speed the completion of their family, to avoid the high costs of future I.V.F. cycles or to ensure that their child has a sibling, among other reasons.source

My comment: I like twins. I really do. So I find it sad that they want to decrease the rate of twins. But from the other hand, if it's more dangerous for the mother, they ought to try. Of course, the choice should remain. Because to some people that's the only possibility to have kids-and the more at once, the better .

Thursday, 3 April 2008

Moral opposition to nanatoch in USA

Nanotech faces moral opposition in the US

20 February 2008

Europe's favourable public opinion on nanotechnology could help the EU to take the lead in this promising research field as recent survey results suggest that a majority of Americans, based on religious beliefs, find it morally unacceptable.

"There seem to be distinct differences between the United States and countries that are key players in nanotech in Europe in terms of attitudes towards nanotechnology," said Professor Dietram A. Scheufele, speaking at the annual meeting of the American Association for the Advancement of Science (AAASexternal ) on 15 February 2008.

Scheufele, a professor of life sciences communication at the University of Wisconsin, Madison, believes that the reason behind this difference in attitude is religion. He said that the survey data showed clear parallels between differences in terms of acceptance of nanotechnology and in terms of moral views. Religion plays an important role in peoples' lives in the US, whereas Europeans "have a much more secular perspective", he argued.

According to Scheufele, those with strong religious convictions view researchers as "playing God" when they create new materials or means to "enhance human qualities" through nanotechnology, biotechnology or stem cell research.

However, Professor Scheufele underlined that ignorance has nothing to do with people's moral doubts on nanotechnology as the survey showed that respondents are well-informed about nanotech and its potential benefits. The issue therefore, according to him, is not about informing these people as they are already informed - and "still oppose it" based on religious beliefs.

Scheufele believes that survey's outcome will affect the way experts explain the technology and its applications in the future. It also means that "the scientific community needs to do a far better job of placing the technology in context and in understanding the attitudes of the American public".

The study carried out by the University of Wisconsin, Madison Survey Center revealed that only 29.5% of Americans find nanotech morally acceptable, whereas significantly higher percentages were observed in Europe. Some 54% of respondents in the UK, 63% in Germany and 72% in France had no moral objection to nanotech.

A recent Eurobarometer surveyPdf external on biotechnology and life sciences also showed striking differences between the American and European public opinion towards genetically modified (GM) food and nanotechnologies. While Europeans fiercely oppose GM food and largely support advances in nanotechnology qualified as "useful to society and morally acceptable",in the US the opposite holds true.

According to the European Commission, public opinion can be a constraint to technological innovation and contribute to specific technological gaps between the United States and Europe.

In early February 2008, the Commission adopted a code of conduct for responsible research on nanosciences (see EurActiv 12/02/08). The EU executive hopes that member states will use the document to promote societal dialogue on nanotech in order to increase understanding and involvement by the general public in the development of new technologies, for example. source

My comment: No comment! It's hight time people to stop putting the name of God in anything the don't understand or that they fear.

Tuesday, 1 April 2008

New AIDS receptor

A new possible way to treat AIDS. Yay! Isn't it weird they know so much about the virus and still it exists? To me it is weird. (and its not a joke!)

Scientists Find New Receptor for
H.I.V.

February 11, 2008

SAN FRANCISCO — Government scientists have discovered a new way that H.I.V. attacks human cells, an advance that could provide fresh avenues for the development of additional therapies to stop AIDS, they reported on Sunday.

The discovery is the identification of a new human receptor for H.I.V. The receptor helps guide the virus to the gut after it gains entry to the body, where it begins its relentless attack on the immune system.

The findings were reported online Sunday in the journal Nature Immunology by a team headed by Dr. Anthony S. Fauci, the director of the National Institute of Allergy and Infectious Diseases.

For years, scientists have known that H.I.V. rapidly invades the lymph nodes and lymph tissues that are abundant throughout the gut, or intestines. The gut becomes the prime site for replication of H.I.V., and the virus then goes on to deplete the lymph tissue of the key CD4 H.I.V.-fighting immune cells.

That situation occurs in all H.I.V.-infected individuals, whether they acquired the virus through sexual intercourse, blood transfusions, blood contamination of needles and syringes, or in passage through the birth canal or drinking breast milk.

The findings appear to provide some, if not the main, answers to how and why that situation occurs.

“They begin to shed light on the mysterious process on why the virus preferentially grows in the gut,” Dr. Greene said in an interview.

Dr. Fauci, James Arthos, Claudia Cicala, Elena Martinelli and their colleagues showed that a molecule, integrin alpha-4 beta-7, which naturally directs immune cells to the gut, is also a receptor for H.I.V. A protein on the virus’s envelope, or outer shell, sticks to a molecule in the receptor that is linked specifically to the way CD4 cells home in on the gut, the researchers said.

Binding of the virus to the integrin alpha-4 beta 7 molecule stimulates activation of another molecule, LFA-1, which plays a crucial role in the spread of the virus from one cell to another. The actions ultimately lead to destruction of lymph tissue, particularly in the gut.

Several other receptor sites for H.I.V. are known. The most important is the CD4 molecule on certain immune cells; the molecule’s role as an H.I.V. receptor was identified in 1984.

Two other important receptors, known as CCR5 and CXCR4, were identified in 1996. CCR5 is a normal component of human cells and acts as a doorway for the entry of H.I.V. People who lack it because of a genetic mutation rarely become infected even if they have been exposed to H.I.V. repeatedly.

“The work we did took nearly two years, and there’s little doubt that what we have found is a new receptor,” Dr. Fauci said in an interview after giving a lecture here, adding that “we certainly have to learn a lot more about it.”

Scientists have sought to identify receptors because they offer targets for the development of new classes of drugs.

For example, last year the Food and Drug Administration approved for AIDS treatment a Pfizer drug, Selzentry or maraviroc, which works by blocking CCR5.

A number of experimental drugs that block the integrin alpha-4 beta-7 receptor are being tested for the treatment of autoimmune disorders. Dr. Fauci said such drugs should also be studied for their potential benefit in AIDS treatment.

One candidate is a drug, Tysabri or natalizumab, that is marketed for treatment of multiple sclerosis, Dr. Fauci said. Biogen/Elan makes Tysabri.

If trials for H.I.V. are successful, Dr. Fauci said, the drugs could be added to existing treatment regimens. source