Science & TechnologyS


Magnify

How Cancer Cells Protect Themselves from Low Levels of Oxygen


ScienceDaily
Sun, 20 Dec 2009 03:00 UTC
Not all regions of a tumor are equal in terms of their oxygen levels. One clinically important implication of this is that tumors with large areas with low levels of oxygen (areas known as hypoxic regions) are associated with poor prognosis and treatment response.

A team of researchers, led by Bradly Wouters, at the University of Toronto, Canada, has determined that a cellular response pathway known as the unfolded protein response pathway helps protect human tumor cells from hypoxia and anticancer irradiation treatment.

Further analysis indicated that the unfolded response pathway increased expression of two proteins involved in a cellular process known as autophagy, which is known to act to protect cells in times of stress.

Importantly, inhibition of autophagy sensitized cultured human tumor cells to hypoxia and sensitized human tumors xenografted into mice to irradiation, leading the authors to suggest that targeting the molecules they identified as important might be of clinical benefit.
Read More...
Magnify

Type of Cell Proves to be Highly Significant in Genetic Studies


ScienceDaily
Sun, 20 Dec 2009 00:00 UTC
Choosing the right cell type is particularly important in genetic studies. This is apparent from research published on 16 October in PLoS Genetics. Dutch researcher Alice Gerrits has shown how variations in the genome can influence the activity of genes. This effect was found to be strongly dependent on the cell type in which these genes were active.

Although all the cells in our body contain essentially the same DNA (genome), they do not all exhibit the same functions. This is usually because different sets of genes are active in different types of cells. Gerrits investigated four types of blood cells in 25 mouse strains with slightly different genomes. In each of the four cell types, she looked for differences in gene activity between the 25 mouse strains and determined which pieces of the genome caused these differences. She discovered that some pieces of the genome had the same effect on the activity of genes in all four cell types. Yet interestingly, a far larger number of pieces exerted an effect on gene activity mostly in one, two or three of the four cell types.
Read More...
Sherlock

Australian Hospital Ship Discovered Off Queensland Coast


Daily Telegraph
Sat, 19 Dec 2009 19:17 UTC
Shipwreak hunters have found the hospital ship Centaur which was torpedoed without warning in 1943 off the Queensland coast, killing 268 people.

Search director David Mearns has advised government officials of the exact location of the wreck and said filming of the wreck would begin in January.

Acting Prime Minister Julia Gillard said Australians and relatives of those who had been aboard the ship were grateful for the find.

"The discovery of the AHS Centaur will ensure all Australians know and commemorate the 268 brave nurses and crew who died in the service of their nation," Ms Gillard said.

"I hope by locating the final resting place of the AHS Centaur, the family and friends of those men and women who were tragically lost find some resolution."
Read More...
Newspaper

Ancient Artifact Pulled Out of Mediterranean Sea


New Tang Dynasty Television
Fri, 18 Dec 2009 20:57 UTC
Archaeologists pulled a section of an ancient Egyptian pylon out of the Mediterranean seabed on Thursday in Alexandria.

The ruin was discovered 11 years ago by a Greek archaeological team, and dates back to around 30 B.C.. It is part of a late Ptolemaic-era temple near the tomb of Cleopatra.

Another important artifact will be brought to the surface in May.
Read More...
Sherlock

Loud and Lazy But Didn't Chew Gum: Ancient Koalas

Mike Archer
University of New South Wales
Sat, 19 Dec 2009 09:00 UTC
Skull fragments of prehistoric koalas from the Riversleigh rainforests of millions of year ago suggest they shared the modern koala's "lazy" lifestyle and ability to produce loud "bellowing" calls to attract mates and provide warnings about predators.

However, the new findings published as the featured cover article in the current issue of The Journal of Vertebrate Paleontology suggest that the two species of koalas from the Miocene (24 to five million years ago) did not share the uniquely specialized eucalyptus leaf diet of the modern koala (Phascolarctos cinereus).

The shift to a wholly eucalyptus diet by modern koalas was an adaptation that probably came later as Australia drifted north, causing its rainforests to retreat and Eucalypts to become the dominant tree of most Australian forests and woodlands.
Read More...
Magnify

Within a Cell, Actin Keeps Things Moving


ScienceDaily
Sat, 19 Dec 2009 06:00 UTC
Image
© University of OregonUO chemist Andrew Marcus has found that actin recruited by mitochondrial cells drive transport in budding yeast cells.
Using new technology developed in his University of Oregon lab, chemist Andrew H. Marcus and his doctoral student Eric N. Senning have captured what they describe as well-orchestrated, actin-driven, mitochondrial movement within a single cell.

That movement -- documented in a paper appearing online the week of Dec. 14-18 ahead of regular publication in the Proceedings of the National Academy of Sciences -- appears to be coordinated by mitochondria's recruitment of actin-related proteins that rapidly assemble into extended fractal-like structures in a molecular chemical reaction known as polymerization. The coordinated movement of mitochondria is important for reproduction of identical daughter cells, and the sorting of mitochondrial DNA into the spinoff cells.

The research was done with a molecular fluorescence technology called Fourier imaging correlation spectroscopy that allows researchers using focused laser beams to see, measure and map the intermittent movement of mitochondria at micron scales. Marcus will discuss the technology, developed with funding from the National Institutes of Health and National Science Foundation, at the 2010 annual meeting of the American Physical Society in Portland, Ore., in March. It also was detailed in a paper published online in October by the journal Annual Reviews of Physical Chemistry.
Read More...
Magnify

Valuable, Rare, Raw Earth Materials Extracted from Industrial Waste Stream


ScienceDaily
Sat, 19 Dec 2009 06:00 UTC
Fierce competition over raw materials for new green technologies could become a thing of the past, thanks to a discovery by scientists from the University of Leeds.

Researchers from Leeds' Faculty of Engineering have discovered how to recover significant quantities of rare-earth oxides, present in titanium dioxide minerals. The rare-earth oxides, which are indispensable for the manufacture of wind turbines, energy-efficient lighting, and hybrid and electric cars, are extracted or reclaimed simply and cheaply from the waste materials of another industrial process.

If taken to industrial scale, the new process could eventually shift the balance of power in global supply, breaking China's near monopoly on these scarce but crucial resources. China currently holds 95 per cent of the world's reserves of rare earth metals in a multi-billion dollar global market in which demand is growing steadily.
Read More...
Magnify

Missing Piece of DNA Replication Puzzle Identified


ScienceDaily
Sat, 19 Dec 2009 03:00 UTC
DNA replication is a basic function of living organisms, allowing cells to divide and multiply, all while maintaining the genetic code and proper function of the original cell. The process, or mechanism, by which this is accomplished presents many challenges as the double helical (coil-shaped) DNA divides into two strands that are duplicated by different methods, yet both strands complete the replication at the same time.

New research by a team from UMDNJ-Robert Wood Johnson Medical School in conjunction with the University of Illinois and published in the Dec. 17 issue of Nature, has addressed this fundamental problem. The study identifies three essential ways the synthesis of the two strands is coordinated by enzymes, settling scientific deliberations on how the two DNA strands are copied in the same time span.

"DNA replication is a fundamental reaction required for the maintenance, survival, and propagation of living cells. It is also a very complex reaction that has been studied for decades without a clear understanding of how the two interwound strands are copied at the same time," says Smita Patel, PhD, professor of biochemistry at Robert Wood Johnson Medical School and lead author of the paper. "Our study explains how the replication is coordinated -- an important piece of the puzzle, because errors in DNA replication can cause disabilities and disease, such as cancer."
Read More...
Magnify

Even Bacteria Get Lonely

Eric Bland
Discovery News
Fri, 18 Dec 2009 07:00 UTC
Image
© Getty ImagesWhen scientists trapped samples of Staphylococcus aureus (shown here) in glass cages, the bacteria acted disturbed and "talked" to themselves.
Bacteria locked in long term solitary confinement change their behavior in strange ways, scientists find, in research that could help explain how infections and cancer spread.

Humans in solitary confinement can go crazy, talking to themselves and trying to break free. Now scientists from New Mexico and New Hampshire are reporting that bacteria locked in solitary confinement know they are locked up, talk to themselves, and try to break free of their imprisonment.

The research could have important health implications, from how an individual bacterium can trigger full-blown infections to how a single human cancer cell can metastasize into a deadly tumor.

"There are many real-world situations where bacteria find themselves alone," said Jeff Brinker, a scientist at the University of New Mexico and co-author of a recent paper in the journal Nature Chemical Biology. "When the bacteria are confined they turn on these virulence pathways," causing infections.
Read More...
Laptop

Google Convicted of Copyright Infringement


Press TV
Fri, 18 Dec 2009 11:36 UTC
Image
© Google Images
A Paris court has found U.S. Internet giant Google Inc. guilty of violating copyright laws by digitizing books and putting them online.

A judge ruled Friday that Google must pay 300,000 euros ($430,000) in damages and interest to French publisher La Martiniere.

Google was also ordered to pay 10,000 euros per day until it removes extracts of the French books from its online database.

Google wants to scan millions of books and make them available online for its users.

This case will be seen as a success for critics who fear that Google will hold a monopoly over information.
Read More...