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Gaming the Future: The Book!

Category: Research

Medication may help slow aging (in fruit flies)

According to an article from the UK-based New Scientist masquerading as a press release ("Keep young and beautiful", by Claire Ainsworth 26 January 2002), a drug called 4-phenylbutyrate (PBA) may help to "extend your lifespan while maintaining your youthful health and vigour. What's more, in the US it's already approved for human use. There is just one snag: to reap the benefits, you have to be a fruit fly."

A team of researchers at the National Institutes of Health and the California Institute of Technology made the discovery by accident when they were testing PBA on flies with neurodegenerative disease. They found that feeding the drug extended maximum lifespan of healthy flies by over 50 per cent, and their average lifespan by one-third. PBA works by blocking the activity of histone deacetylases, enzymes involved in switching genes on and off, including the one for superoxide dismutase, a protein well known for its anti-ageing effects. The researchers will be testing the drug on mice very soon.

The research was published in the Proceedings of the National Academy of Sciences (vol 99, p 838).

ACT reports method for parthenogenic embryonic stem cells

According to a press release (1 February 2002), researchers from Wake Forest University School of Medicine and Advanced Cell Technology (ACT) of Worcester, Mass. report in the 1 February 2002 issue of Science that they have developed a large variety of specialized cell types — including heart and brain cells — from embryonic monkey stem cells through a process called parthenogenesis. The researchers reported that they had generated a "pluripotent" stem cell line. From that cell line, they already have produced brain neurons, heart muscle, smooth muscle, beating ciliated epithelial cells and a number of other kinds of cells, demonstrating, they said, "broad differentiation capabilities of primate stem cells derived by parthenogenesis." The parthenogenetic process leads to stem cells without creating embryos that normally require an egg from the mother and a sperm from the father. Parthenogenesis is defined as a process by which embryonic development is initiated directly from an unfertilized egg cell.

Additional coverage can be found in articles from Reuters News Service, United Press International, the New York Times, and Nature Science Update.

An interesting perspective on the announcement can be found in another press release don`t think the fact that a parthenogenetic embryo is not viable solves the ethical problems for those who object to using human embryos for stem cells," says Dr Donald Bruce, Director of Society Religion and Technology Project of the Church of Scotland, which has been examining ethical issues of cloning and stem cells since 1996.

Adult stem cell line may serve for regenerative medicine

from the regenerative-medicine dept.
Numerous reports appeared in late-January 2002 in response to a press release (23 January) that reports on a claim by Dr. Catherine M. Verfaillie and colleagues at the University of Minnesota Stem Cell Institute (SCI) that they have isolated a type of stem cell found in adults that can turn into every single tissue in the body. Previously, only stem cells from early embryos were thought to be able to do this. If the finding is confirmed, it will mean cells from your own body could one day be turned into all sorts of perfectly matched replacement tissues and even organs. The finding generated a high level of interest because, if confirmed, there would be no need to resort to therapeutic cloning — cloning human embryos to get matching stem cells from the resulting embryos. Nor would you have to genetically engineer embryonic stem cells (ESCs) to create a "one cell fits all" line that doesn't trigger immune rejection. The discovery of such versatile adult stem cells will also fan the debate about whether embryonic stem cell research is justified.

Additional coverage can be found in articles from the New York Times ("Scientists Herald a Versatile Adult Cell", by N. Wade and S.G. Stolberg, 25 January 2002) and United Press International ("Adult stem cell findings lauded", 24 January 2002).

In related news that demonstrates the importance of this line of research, Dr. Verfaillie announced in another press release (30 January 2002) that her team has demonstrated, for the first time, the ability of adult bone marrow stem cells to expand in vitro as endothelial cells (which line blood- and lymphatic vessels) and then engraft in vivo and contribute to new growth of blood vessels (neoangiogenesis). The report appeared in the 1 February 2002 issue of the Journal of Clinical Investigation. Verfaillie and her colleagues announced late last year that these cells, called multipotent adult progenitor cells (MAPCs), demonstrate the potential to differentiate beyond mesenchymal cells, into cells of the visceral mesodermal origin, such as endothelium, and may be capable of differentiating into nonmesodermal cell types, such as neurons, astrocytes, oligodendrocytes, and liver.

ACT claims to grow artificial kidney from stem cells

According to a report from the UK-based New Scientist (" ëFunctionalí kidneys grown from stem cells", by Claire Ainsworth, 29 January 2002), researchers at Advanced Cell Technology in the U.S. claim to have grown functional bovine kidneys using stem cells taken from cloned cow embryos. The report says the ACT researchers, working in collaboration with a group at Harvard University, coaxed the stem cells into becoming kidney cells, and then "grew" them on a kidney-shaped scaffold. The two-inch-long mini-kidneys were then transplanted back into genetically identical cows, where they started making urine. If confirmed, the work raises the prospect of using stem cells taken from human patients with kidney failure to create new organs for transplant. ACT did not reveal details, and the work has not yet been published in a peer-reviewed journal. As the NS article notes, no details are available as to exactly what these miniature kidneys are, and whether they are in fact complete, functional organs. The kidney is a very complex organ, with an intricate supply of blood vessels that are key to its ability to filter blood.

Additional coverage appeared in the New York Times ("Company Says It Used Cloning to Create New Kidneys for Cow", by K. Chang, 31 January 2002).

Biotech company claims to have automated cloning with chip

from the brave-new-world? dept.
According to a press release (30 January 2002) issued by the UK-based New Scientist Magazine, a specialized chip that will automatically create hundreds of cloned embryos at a time is being developed by Aegen Biosciences, a Californian biotech company. If true, the chip should help make cloning cheap and easy enough for companies to mass-produce identical copies of the best milk or meat producing animals for farmers. It might even be used for cloning human embryos. According to the release, the chip automates the laborious process of nuclear transfer, the key step in cloning. At present it takes hours of painstaking work with a microscope to remove the nucleus of an egg cell and replace it by fusing the denucleated egg with another cell.

Purdue researchers reveal structure of viral DNA-injector

from the biological-nanomachines dept.
According to a lengthy press release (30 January 2002), scientists at Purdue University have solved the three-dimensional structure of the bacteriophage T4 virus, which includes a complex syringe-like structure designed to inject viral DNA into a host cell. The researchers reported their work on this natural nano-mechanical device in the 31 January 2002 issue of Nature.

The study also reveals how the virus binds to the surface of the host, punctures the cell wall with a syringe-like tube and injects its own genetic blueprint into the cell. The virus uses its long-tail fibers to recognize its host and to send a signal back to the baseplate. Once the signal is received, the short-tail fibers help anchor the baseplate into the cell surface receptors. As the virus sinks down onto the surface, the baseplate undergoes a change — shifting from a hexagon to a star-shaped structure. At this time, the whole tail structure shrinks and widens, bringing the internal pin-like tube in contact with the outer membrane of the E. coli cell. As the tail tube punctures the outer and inner membranes of the E. coli cell, the virus' DNA is injected through the tail tube into the host cell. This genetic information then sets the cell's machinery to work creating replicas of the virus.

Analysis of the cell-puncturing device also reveals a structure that may hold potential for applications in nanotechnology, such as microscopic probes, said Michael Rossmann, Hanley Distinguished Professor of Biological Sciences at Purdue who directed the study. "This a very stable structure that looks like a small stylus. It might be useful as a probe in an atomic force microscope, which employs a probe of molecular dimension."

Update: Additional information on this research, including links to high-resolution images of the T4 virus and the viral baseplate mechanism and a news video, is available on the U.S. National Science Foundation (NSF) website.

Synthetic antioxidant enzyme prevents type 1 diabetes in mice

According to a press release (25 January 2002), a new study by researchers at National Jewish Medical and Research Center and the University of Colorado Health Sciences Center shows that a synthetic antioxidant can delay and prevent the onset of autoimmune diabetes in mice. The antioxidant protected insulin-producing beta cells from lethal oxygen radicals generated in diabetes. The antioxidant also blocked the ability of the immune system to recognize beta cells, the target of the autoimmune attack in diabetes. The findings suggest that antioxidants may be useful against diabetes as well as other autoimmune diseases and organ-transplant rejections. The researchers used a synthetic catalytic antioxidant developed several years earlier by one of the researchers, and now licensed by Incara Pharmaceuticals Corporation. The antioxidant, dubbed AEOL 10113, mimics the naturally occurring antioxidant superoxide dismutase, but is effective against a wider range of antioxidants and lasts longer in the body. The findings, published by in the February issue of Diabetes, suggest that antioxidants may be useful against diabetes as well as other autoimmune disorders. Additional article can be found in this article (25 January 2002). from United Press International.

This research is following a line similar to that being explored by MetaPhore Pharmaceuticals, which is also testing a family of synthetic analogs of superoxide dismutase (see Nanodot posts from 12 July and 14 December 2001).

Heath team at UCLA reports advance in nanotube molectronics

Not content with the collaborative work with HP Labs that recently earned a molecular electronics patent (see Nanodot post from 24 January 2002), UCLA chemistry professor and California NanoSystems Institute researcher James Heath and his coworkers have announced an advance in using crossed arrays of carbon nanotubes to form molecular electronic circuits. The research was published in Angewandte Chemie International Edition, v41, pp 353 – 356 (18 January 2002). A summary of the report appeared on the Nature Science Update website ("Cylinders make circuits spontaneously: Carbon nanotubes assemble themselves into electronic grids", by Philip Ball, 29 January 2002).

Viral shells as nanochemical building blocks

According to a press release (25 January 2002), researchers at The Scripps Research Institute (TSRI) and The Skaggs Institute for Chemical Biology have found a way to attach a wide range of molecules to the surface of a virus, enhancing the virus with the properties of those molecules. The researchers say their technique may find applications in materials science, medicine, and molecular electronics, including the possibility of building circuits of conducting molecules on the surfaces of the viruses and form a component of a molecular-scale computer, or a new type of "nanowire." The work is reported in the 1 February 2002 issue of Angewandte Chemie.

The researchers found a method of putting a chemically reactive cysteine residue (a type of amino acid) on the surface of each of the 60 identical protein modules that make up the viral shell. The shell has an icosahedral shape, which provides 60 equivalent sites for attaching molecules. The researchers report they have been able to attach fluorescent dyes and clusters of gold molecules to the cysteine residues, which could be easily imaged. They also have successfully attached biotin (Vitamin B), sugars, and organic chemicals. The technique can be used to immobilize large molecules on the viral surface — whole proteins even. In addition, the virus particles can self-organize into network arrays in a crystal, which may make it a useful building block for various applications in nanotechnology. "You can, in principle, determine the type of assembly you get by programming the building blocks," says one researcher.

Update: Additional coverage is available in this article from United Press International

Samsung demonstrates very cold nanotube crud can form transistors

An article on the Technology Research News website ("Nanotube array could form chips", by Ted Smalley Bowen) describes work by a group of researcers from the Samsung Advanced Institute of Technology and the Chonbuk National University in Korea who have made nanotube field-effect transistors in bulk by a relatively crude process that involves growing them in vertical bunches, then using electron beam lithography and ion etching to make the source, gate and drain electrodes that control the flow of electrons. Their carbon nanotube transistors worked at temperatures up to an extremely cold -243 degrees Celsius. The report dryly notes that the transistors will need to work at much warmer temperatures to be used in practical devices, and includes comments from other nanotube researchers to the effect that the researchers' method is still very rough, and they did not demonstrate that individual transistors could be accessed. The nanotubes rough composition limits their use, said Yue Wu, associate professor of physics at the University of North Carolina. "The carbon nanotubes are very defective. The device won't work at room temperature because the tubes are not clean semiconductors," he said. The work was reported in the 26 November 2001 issue of Applied Physics Letters.

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