|
|
|
NEWSBITS
Scientists gene-engineer first human stem cells
Scientists have said that they had, for the first time, genetically manipulated human stem cells — a step toward making the body’s so-called master cells into a useful tool.
Using the method that made the laboratory mouse so valuable to genetic researchers, the team at the University of Wisconsin deleted a disease gene from human embryonic stem cells.
They now have a way to help control how the cells develop, so they can direct them to become brain tissue, or perhaps heart cells or pancreatic cells, said Dr Thomas Zwaka, who conducted the study with stem cell expert American James Thomson. “It allows us to manipulate every part of the human genome that we want,” said Zwaka, a German-born medical doctor and molecular biologist.
Extracted when the fertilized egg has divided just a few times, each cell still “remembers” how to become any kind of cell in the body. Once they get older, cells are programmed and cannot easily change direction in development.
The hope is that these cells can be used to replace the brain cells destroyed in Parkinson’s disease, the cells that die in type-I diabetes or damaged spinal cords.
But so far it has been hard to program these cells. Zwaka, whose work is published in the journal Nature Biotechnology, said this method will now help scientists do that.
“You can purify tissues,” he said. One problem with human embryonic stem cells is they tend to remember a little too much, and they can form a random mass known as a teratoma instead of the desired tissue. With this method, the genes can be manipulated so as to control the kind of tissue the cells form.
His team is already trying this with the dopamine-producing brain cells that die off on Parkinson’s, an incurable and fatal brain disease that eventually paralyzes victims.
The method could also be used, Zwaka said, to create “universal” donor batches, or cell lines, of cells. The genes that cause the body’s immune system to reject foreign tissue could be removed. This could bypass the need for therapeutic cloning — another promising but unproved method that involves taking a cell from a patient using cloning technology to make a very early embryo, and then extracting the cells from it for a personalized transplant.
One big question is whether the method could be used to make designer babies. If genes can be deleted from or added to mice, why not humans?
Zwaka said this is impossible to do with existing technology and also undesirable. “You’d have to recreate the entire baby from embryonic stem cells,” he said. “No one knows how to generate a human out of embryonic stem cells and who wants to do that?” — Dawn ScienceDotcom Report
Robots get cheeky
Meet K-bot, probably the most sophisticated robot head yet developed.
It is the creation of David Hanson, a former Disney employee now working at the University of Texas-Dallas.
The android head has cameras behind its eyes that will follow your movements; sophisticated software drives tiny motors under the polymer skin to mimic your facial expressions.
K-bot will smile, sneer, frown and even squint. Its 24 mechanical muscles react in under one second to produce the copycat visage.
The two-kilogram head was shown off to the annual meeting of the American Association for the Advancement of Science (AAAS) in Denver.
Delegates were being updated on the latest developments in biologically inspired intelligent robotics.
“This is the face for social robotics,” said Mr Hanson, who is building the machine as part of his PhD studies. “The human face is the most natural paradigm for human-computer interactions. This is how we will interact with the computers of tomorrow.”
Remarkably, the main components in this advanced machine have been built from parts that cost less than $400, and Hanson believes this cost can be dramatically reduced.
“The goal is to turn these robot faces into a main mass-manufacture technology. As these robots reduce in size and weight, they will become more easily distributed in science laboratories.”
When that happens, Hanson believes the development of the head will be accelerated. The basic unit will become a platform to try out other technologies such as artificial muscles.
“You could distribute these things to labs all around the world and then you would have a standardised humanoid intelligence platform that can be integrated with locomotion robots and natural language processors.
“You could then begin to knit together all the various components of artificial intelligence into a cohesive integrated humanoid emulation robot.
“But fundamentally you have to have a good face otherwise you will not relate to it.” — Dawn ScienceDotcom Report
New worm lures with celebrity photos
A new computer worm has surfaced that purports to contain revealing photos of Catherine Zeta-Jones and other celebrities but actually installs a backdoor program that could allow someone to take over the computer, anti-virus company Sophos said on Thursday.
Users of the Kazaa file-sharing service and IRC instant messaging are at risk, although there have been no reports of infections yet, UK Sophos said.
The worm-infected file claims to contain compromising photos of female celebrities including, Zeta-Jones, Britney Spears and Shakira. Once the file is opened, a backdoor “Trojan horse” is downloaded onto the victim’s computer.
The use of Zeta-Jones’ name comes as she and husband Michael Douglas are waging a legal battle against a UK tabloid over unauthorized wedding photos, the company noted. Zeta-Jones was also recently nominated for an Oscar for best supporting actress for her sultry role in the film “Chicago.”
Sophos recommends that people update their anti-virus software to prevent infection.
The technique is not new. Previous computer worms have spread by tricking e-mail users with supposed photos of Russian tennis start Anna Kournikova and obscene subject lines. — Dawn ScienceDotcom Report
Hot plasma may have entered the shuttle
The extreme heat observed on the shuttle Columbia’s left side during its fatal re-entry could have been caused by hot plasma penetrating the craft’s wheel well, according to independent investigator.
Plasma is the super-heated gas that surrounded the shuttle as it streaked toward a landing at Kennedy Space Centre on Feb 1. Plasma typically envelops a fast-descending space shuttle, but this time, preliminary analysis indicates, it may have gotten inside the spacecraft’s protective surface.
“Preliminary analysis by a NASA working group this week indicates that the temperature indications seen in Columbia’s left wheel well during entry would require the presence of plasma,” the Columbia Accident Investigation Board said in a statement forwarded by NASA. However, the board said the heat was so excessive that it could not have been caused by the absence of just one missing tile in the last minutes of flight. This is significant since questions have centered on the possibility that some of Columbia’s heat-shielding tiles were knocked off by a piece of foam insulation that fell off the shuttle’s external fuel tank about 80 seconds after launch, apparently striking the left wing.
The board said investigators were looking at other ways the shuttle’s skin might have been breached to let plasma into the wheel well area or elsewhere in the wing. They also discounted fears that a problem with the landing gear on the left side of the spacecraft might have caused the shuttle to disintegrate over Texas, as a NASA engineer suggested in an e-mail two days before the shuttle’s demise. — Dawn ScienceDotcom Report
IBM tops US patent list for the tenth year in a row
IBM generated the most US patents in 2002, the tenth consecutive year that it led the world, according to figures released last week by the United States Patent and Trademark Office.
IBM was awarded 3,288 patents, nearly doubling the output of the second most productive company. Among these patents are:
— Sharing computing tasks over a network which allows a computer to call for “help” and send jobs or tasks to other computers over a network. The “helper” computers will automatically perform the assigned tasks and return the results to the requesting computer
— Detecting environmental impact on system faults which details a method for a computer to monitor itself and determine if its environment is causing a fault or failure of components in the system, such as the power supplies or cooling components
— Automatic network reconnection which describes how a computer can automatically detect when it has been moved in a work environment and will subsequently establish new network settings to reconnect to the network.
Manufacturing carbon nanotubes which describes a method for controllably modifying nanotubes for the fabrication of electronic devices such as field-effect transistors. — Dawn ScienceDotcom Report
|
|
|
|
