A team of American scientists reported Sunday that they had widened the scope of a Japanese breakthrough in stem cells that many experts have hailed as the greatest medical achievement of 2007.
In November, Shinya Yamanaka of Kyoto University and colleagues announced they had reprogrammed human skin cells to have the multiple potency of stem cells culled from human embryos, AFP said.
Stem cells are early cells that differentiate into one of the 220 different types of cells in the body.
Medical researchers hope that one day, these cells can be grown in a lab dish to become specific replacement tissue to replenish organs ravaged by disease or damaged in accidents or warfare.
Yamanaka’s team used a retrovirus to deliver four genes into skin cells taken from a mouse and an adult human.
In essence, this turned the clock back so that these cells lost their differentiated profile and became so-called induced pluripotent stem cells, or iPS.
Reporting on Sunday in Nature, a team led by George Daley of the Children’s Hospital, in Boston, Massachusetts, says they have been able to use the same four genes to derive iPS from foetal lung and skin cells, from neo-natal skin cells as well as from skin samples taken from a healthy human volunteer.
The research is important as it marks a step forward to “patient-specific“ stem cells--in other words, transplanted stem cells that carry the same genetic code as the patient and thus cannot be rejected as alien by the body’s immune system, they say.
The researchers also found that they could generate iPS without a cancer gene called c-Myc that has been implicated in tumors in many lab mice in earlier experiments.
That replicates a similar finding by Yamanaka’s own team, published after the first breakthrough was reported.
The researchers stress, though, that many hurdles lie on the road ahead before iPS is certified as safe and effective and can be used to grow replenishment tissue.
“Clinical success with human iPS cells must await the development of methods that avoid potentially harmful genetic modification,“ they write, saying that “a worthy goal“ would be to find biochemicals to replace gene infiltration for inducing iPS.

A scientist holds a prototype vaccine against the bird flu virus in 2007.

China has made good progress in developing a human vaccine against the deadly bird flu virus, with a second phase of tests showing it to be safe and effective, state press reported.
About 400 people aged between 18 and 60 who were given the vaccine between September and November this year had shown no ill side effects, and the drug had “performed well“, Xinhua news agency said, citing an official involved, AFP said.
“China is capable of producing bird flu vaccines for humans in appropriate quantities,“ Zhang Jiansan, the vice general manager of Beijing-based vaccine producer Sinovac Biotech, was quoted as saying.
The World Health Organisation gave a cautious response to the announcement.
“Around a year ago China announced the first phase of clinical tests for a human vaccine,“ a Beijing-based WHO spokeswoman said.
“It’s encouraging that China is making progress but WHO needs more information to properly comment. We’ll be talking to the Chinese researchers for more information.“
Many countries and firms have been developing vaccines to combat the H5N1 strain of the bird flu, which has killed more than 200 people worldwide, mostly in Southeast Asia, since late 2003.
Seventeen people have died of the bird flu in China.
Scientists have warned that the virus could kill many more people around the world if it mutates into a form that can be easily passed among humans, rather than from poultry to people as is now the case.

When Javier Rodriguez Molina visited the Atocha Train Station Memorial in Madrid last summer, the Barcelona native felt a great sadness for the victims of the March 11, 2004 Madrid train bombings.
But he also felt some hope that his advanced emergency technology work at University of California, San Diego can some day save lives in similar disasters, according to ScienceDaily.
Police, firefighters and other emergency workers responding to natural or manmade disasters may someday save more lives with the help of “Gizmo,“ an advanced mobile wireless communications device.
Rodriguez is Gizmo’s lead gadgeteer. He’s an electrical engineering graduate student and programmer analyst at UC San Diego’s California Institute for Telecommunications and Information Technology (Calit2), one of the most advanced, interdisciplinary research institutes in the world.
Gizmo, which looks like a cross between a remote-controlled toy truck and a lunar landing vehicle, may eventually transform disaster response by collecting and transmitting in real time any information that emergency personnel need via any communications system they’re using.
“In almost any emergency, the most important thing is immediate, accurate information,“ Rodriguez said. “Gizmo will eventually be able to go anywhere on its own and send back in real time whatever information you might need.“
From the Circuits Lab at Calit2, Rodriguez hopes to build many varieties of Gizmos-- even one that flies. The devices could go anywhere that it’s too dangerous for humans, including urban emergencies such as hostage situations, terrorist attacks or a building collapse.
The current Gizmo is the size of a remote-controlled toy truck. But future models may be alternately much smaller (so they could enter a hostage situation without being detected), or much bigger, such as a full sized truck, which could penetrate disaster situations even in the harshest conditions, such as a hurricane.
“Using technology to try to save lives is the most important thing for me now,“ Rodriguez said. “I’m taking part in work that can make people more secure by helping police, helping firefighters, helping anybody who is responding to a dangerous situation.“
Working under Ramesh Rao, an internationally recognized expert in emergency technology and director of the UC San Diego division of Calit2, Rodriguez is now guiding a team of engineering undergraduates who are building Gizmos, which create their own wireless network bubble wherever they go.
One Gizmo can create a wireless network 200 meters in diameter; several working in conjunction can create an exponentially larger network.

Frying caused a significantly higher loss of antioxidants in comparison to the water-based cooking methods.

In a finding that defies conventional culinary wisdom, researchers in Italy report that cooking vegetables can preserve or even boost their nutritional value in comparison to their raw counterparts, depending on the cooking method used.
Their study is scheduled for the Dec. 26 issue of ACS’ Journal of Agricultural and Food Chemistry, Physorg.com reported.
Nicoletta Pellegrini and colleagues note that although many people maintain that eating raw vegetables is more nutritious than eating cooked ones, a small but growing number of studies suggest that cooking may actually increase the release of some nutrients.
However, scientists are seeking more complete data on the nutritional properties of cooked vegetables, the researchers say.
In the new study, the researchers evaluated the effects of three commonly-used Italian cooking practices--boiling, steaming, and frying--on the nutritional content of carrots, zucchini and broccoli.
Boiling and steaming maintained the antioxidant compounds of the vegetables, whereas frying caused a significantly higher loss of antioxidants in comparison to the water-based cooking methods, they say.
For broccoli, steaming actually increased its content of glucosinolates, a group of plant compounds touted for their cancer-fighting abilities.
The findings suggest that it may be possible to select a cooking method for each vegetable that can best preserve or improve its nutritional quality, the researchers say.

For those of you tucking into dark chocolate this Christmas using the excuse it is good for you, think again.
A top medical journal said any health claims about plain chocolate may be misleading, BBC said.
Plain chocolate is naturally rich in flavanols, plant chemicals that are believed to protect the heart.
But an editorial in the Lancet points out that many manufacturers remove flavanols because of their bitter taste.
Instead, many products may just be abundant in fat and sugar--both of which are harmful to the heart and arteries, the journal reported.
Previous studies have suggested that plain chocolate can help protect the heart, lower blood pressure and aid tiredness.
But the Lancet said, “Dark chocolate can be deceptive.
“When chocolate manufacturers make confectionery, the natural cocoa solids can be darkened and the flavanols, which are bitter, removed, so even a dark-looking chocolate can have no flavanol.
“Consumers are also kept in the dark about the flavanol content of chocolate because manufacturers rarely label their products with this information.“
And the journal also pointed out that even with flavanols present, chocolate-lovers should be mindful of the other contents.
“The devil in the dark chocolate is the fat, sugar and calories it also contains.
“To gain any health benefit, those who eat a moderate amount of flavanol-rich dark chocolate will have to balance the calories by reducing their intake of other foods--a tricky job for even the most ardent calorie counter.
“So, with the holiday season upon us, it might be worth getting familiar with the calories in a bar of dark chocolate versus a mince pie and having a calculator at hand.“