October 22, 2006, 11:18 PM CT

Genes And Perception Of Pain

A new NIH-funded study shows that a specific gene variant in humans affects both sensitivity to short-term (acute) pain in healthy volunteers and the risk of developing chronic pain after one kind of back surgery. Blocking increased activity of this gene after nerve injury or inflammation in animals prevented development of chronic pain.

The gene in this study, GCH1, codes for an enzyme called GTP cyclohydrolase. The study suggests that inhibiting GTP cyclohydrolase activity might help to prevent or treat chronic pain, which affects as many as 50 million people in the United States. Doctors also may be able to screen people for the gene variant to predict their risk of chronic post-surgical pain before they undergo surgery. The results appear in the October 22, 2006, advance online publication of Nature Medicine.*.

"This is a completely new pathway that contributes to the development of pain," says Clifford J. Woolf, M.D., of Massachusetts General Hospital and Harvard Medical School in Boston, who led the research. "The study shows that we inherit the extent to which we feel pain, both under normal conditions and after damage to the nervous system."

Dr. Woolf carried out the study in collaboration with Mitchell B. Max, M.D., of the National Institute of Dental and Craniofacial Research (NIDCR) in Bethesda, Maryland, and colleagues at the National Institute on Alcoholism Abuse and Alcoholism (NIAAA) and elsewhere. Dr. Woolf's work was funded by the National Institute of Neurological Disorders and Stroke (NINDS). The research team also received funding from NIDCR, NIAAA, and other organizations.........

Posted by: Sean      Permalink         Source

October 22, 2006, 11:07 PM CT

Geological Feature Key To Finding Tombs

A 42-year-old method for finding water, monitoring pollution and helping with tunneling may also be a way to locate and protect tombs in the Valleys of the Kings and Queens and other burial sites in Egypt, as per Penn State researchers.

The idea that fracture traces could bare some connection to the rock cut tombs found in Egyptian valleys came to Katarin A. Parizek as she toured Egypt. K. Parizek, the daughter of Richard R. Parizek, professor of geology and geo-environmental engineering at Penn State, is a digital photographer, graphic designer and geologist. In 1992, on a Nile cruise to the Valley of the Kings near Luxor, she recognized the geological structures.

"A number of of the tombs were in zones of fracture concentration revealed by fracture traces and lineaments," says K. Parizek, an instructor in digital photography. "I knew that these fractures were what Dad used to find water or to plan dewatering projects."

Fracture traces are the above-ground indication of underlying zones of rock fracture concentrations. In 1964, Laurence H. Lattman and R. Parizek published a paper on fracture traces that indicated where increased weathering and permeability occurred and where people could drill wells more efficiently. These fracture traces can be between 5 and 40 feet wide, but average about 20 feet, and can be as long as a mile.........

Posted by: William      Permalink         Source

October 22, 2006, 8:47 PM CT

Portable 'lab on a chip'

Testing soldiers to see if they have been exposed to biological or chemical weapons could soon be much faster and easier, thanks to MIT researchers who are helping to develop a tiny diagnostic device that could be carried into battle.

By tweaking the design of a tiny pump, researchers affiliated with MIT's Institute for Soldier Nanotechnologies have taken a major step towards making an existing miniature "lab on a chip" fully portable, so the tiny device can perform hundreds of chemical experiments in any setting.

"In the same way that miniaturization led to a revolution in computing, the idea is that miniature laboratories of fluid being pumped from one channel to another, with reactions going on here and there, can revolutionize biology and chemistry," says Martin Bazant, associate professor of applied mathematics and leader of the research team.

Within the lab on a chip, biological fluids such as blood are pumped through channels about 10 microns, or millionths of a meter, wide. (A red blood cell is about 8 microns in diameter.) Each channel has its own pumps, which direct the fluids to certain areas of the chip so they can be tested for the presence of specific molecules.

Until now, scientists have been limited to two approaches to designing labs on a chip, neither of which offer portability. The first is to mechanically force fluid through microchannels, but this requires bulky external plumbing and scales poorly with miniaturization.........

Posted by: Sean      Permalink         Source

October 22, 2006, 8:40 PM CT

How To Seal DNA Breaks

Scientists investigating an important DNA-repair enzyme now have a better picture of the final steps of a process that glues together, or ligates, the ends of DNA strands to restore the double helix.

The enzyme, DNA ligase, repairs the millions of DNA breaks generated during the normal course of a cell's life, for example, linking together the abundant DNA fragments formed during replication of the genetic material in dividing cells.

"Our study shows that DNA ligase switches from an open, extended shape to a closed, circular shape as it joins DNA strands together," says the study's senior author Tom Ellenberger, D.V.M, Ph.D., the Raymond H. Wittcoff Professor and head of the Department of Biochemistry and Molecular Biophysics at Washington University School of Medicine in St. Louis. "The ligase resembles a wristwatch that latches around the DNA ends that are being joined".

DNA is surprisingly reactive and under continuous assault from environmental toxins and reactive cellular metabolites. A means of repairing DNA damage is vital to maintaining the integrity of the genetic blueprint.

When these repair processes go awry, cells can malfunction, die or become cancerous, so researchers would like to know how "DNA mechanics" do their jobs. DNA ligases are attractive targets for the chemotherapy of cancer and other diseases.........

Posted by: Ashley      Permalink         Source

October 22, 2006, 8:23 PM CT

Subatomic Quick-change Artist

It's taken 19 long years of painstaking, high-precision experiments, but it's finally official: Physicists have announced the observation of a subatomic particle known as the Bs (pronounced "B sub s") meson switching between matter and antimatter states at a mind-boggling 3 trillion times per second.

The work could lead to a better understanding of the early universe, in which these particles were present in great abundance. It will also help physicists refine different theoretical models in high-energy physics.

Christoph Paus, associate professor of physics at MIT, led the analysis of years' worth of data from the world's highest-energy particle accelerator. Representing the 700-member team of the Collider Detector at Fermilab (CDF) collaboration, Paus presented the discovery to the scientific community Sept. 22 at the Fermi National Accelerator Laboratory in Illinois.

"The CDF result is an exquisite example of precision measurements extracting a small and subtle effect from nature," said Richard G. Milner, professor of physics and director of MIT's Laboratory for Nuclear Science (LNS). "The MIT group under the leadership of Christoph Paus, and with the strong support of the U.S. Department of Energy Office of High Energy Physics, the MIT Department of Physics and the MIT School of Science, constructed a key detector that was essential to this measurement".........

Posted by: Sarah      Permalink         Source

October 22, 2006, 8:00 PM CT

Entanglement Of Atom Pairs

Physicists at the Commerce Department's National Institute of Standards and Technology (NIST) have taken a significant step toward transforming entanglement-an atomic-scale phenomenon described by Albert Einstein as "spooky action at a distance"-into a practical tool. They demonstrated a method for refining entangled atom pairs (a process called purification) so they can be more useful in quantum computers and communications systems, emerging technologies that exploit the unusual rules of quantum physics for pioneering applications such as "unbreakable" data encryption.

The NIST work, published in the Oct. 19, 2006, issue of Nature,* marks the first time atoms have been both entangled and subsequently purified; previously, this process had been carried out only with entangled photons (particles of light). The NIST demonstration also is the first time that researchers have been able to purify particles nondestructively. Direct measurement would destroy the delicate entangled state of atom pairs; the new experiment gets around this problem by entangling two pairs of atoms and measuring only one pair.

Entanglement is a curious property of quantum physics that links the condition and behavior of two or more particles, such as atoms or photons. Entanglement can occur spontaneously when two atoms interact. For the initial interaction, the atoms have to be in close proximity, but the entanglement may persist even if they are physically moved apart. The quality of the entanglement can be degraded by a number of environmental factors, such as fluctuating magnetic fields, so the process and the transport of entangled particles need to be tightly controlled in technological applications. The purification process implemented at NIST can clean up or remove any distortions or "noise" regardless of the source by processing two or more noisy entangled pairs to obtain one entangled pair of higher purity.........

Posted by: Sarah      Permalink         Source

October 22, 2006, 7:55 PM CT

Fossilized Liquid Assembly

From a butterfly's iridescent wing to a gecko's sticky foot, nature derives extraordinary properties from ordinary materials like wax and keratin. Its secret is hierarchical topology: macroscale structures assembled from microscale components of varying sizes. Borrowing a page from nature's playbook, scientists at the National Institute of Standards and Technology (NIST) have developed a novel platform for the self-assembly of experimental hierarchical surfaces in a fluid. Their work offers diverse industries a new way to generate and measure self-assembly at the nano-scale.

A butterfly's wings shimmer because light plays upon tiny rows of scales, like tiles on a Spanish roof. The gecko sticks to surfaces because its feet are patterned with microscopic hairs, each hair tipped with hundreds of even tinier projections. Beads of water roll off the lotus's leaf because its surface is streaked with microscopic peaks, each with a finer structure, that makes the surface "super hydrophobic." These enhanced properties-other possibilities include super adhesion and low friction-have attracted the attention of design engineers for applications from bioengineered tissues to photonic crystals to submarines that slice through water with minimal drag.

Creating these topologically complex, self-assembled surfaces for study has been a challenge. If the components are mixed on a surface, that substrate affects how they assemble; if mixed in a solvent and dried, the drying process similarly distorts the results. In a recent paper*, the NIST team detailed a much simpler and faster system they dubbed "fossilized liquid assembly" to create experimental models of hierarchical topologies in which the components are allowed to mix and assemble freely in a fluid, and then quickly "frozen" in place for study. The key is the use of solutions of water and a special monomer that polymerizes-links together-when exposed to ultraviolet light. Like an oil-water mixture, the fluid forms liquid interfaces that can be manipulated to create a desired hierarchical structure and then suddenly solidified with a burst of UV light.........

Posted by: Kevin      Permalink         Source

October 22, 2006, 7:46 PM CT

SRM Can Help Control Heavy Metal Content

A new reference material developed by the National Institute of Standards and Technology (NIST) can help the agriculture industry and state regulators monitor the concentrations of several potentially hazardous heavy metal contaminants in fertilizers.

Modern multi-nutrient fertilizers produced for home and agricultural use are formulated from multiple sources to provide significant amount of nitrogen, phosphorus and potassium, the major plant nutrients, and lesser or even trace amounts of other nutrients needed by different crops, such as boron, calcium, iron and zinc.

Until relatively recently, fertilizers were tested and certified for their nutrient content, but little attention was paid to the possibility of heavy metal contaminants introduced by the mineral sources used to prepare the fertilizer. However, in response to incidents of heavy metal contamination of cropland, several states have enacted regulations in the past seven years that limit the amounts of some potentially hazardous non-nutritive elements in fertilizers. Several countries, including Japan, China, and Australia, and the European Union, also limit the amount of selected elements in fertilizers.

While fertilizer manufacturers and state regulatory authorities have needed to develop analytical methods to implement these regulations, until now there have been no certified reference materials available that they could use to validate the accuracy of their measurements. It can be difficult to measure accurately trace levels of some metals in a chemically complex mixture like fertilizer.........

Posted by: Kevin      Permalink         Source

October 19, 2006, 9:59 PM CT

Kartchner Caverns To Become Microbial Observatory

University of Arizona scientists will investigate the lives of Kartchner Caverns State Park's tiniest inhabitants with the help of a $1.6 million grant from the National Science Foundation.

The five-year grant to the UA will add Kartchner Caverns, part of the Arizona State Parks system, to the National Science Foundation's worldwide network of Microbial Observatories.

Research at the networks' sites is revealing the goings-on of the Earth's smallest and most poorly known life forms. Kartchner Caverns is the only cave in the network.

"We thought Kartchner Caverns waccording tofect for this. It's one of the top 10 caves in the world in terms of mineralogical diversity," said principal investigator Raina M. Maier, a UA professor of soil, water and environmental science. "And the development of Kartchner is a model internationally for the development of a cave as a living system. It's a model for preservation".

The scientists will catalog the microbial inhabitants of the cave, study how tourism affects their diversity and investigate whether microorganisms are involved in the growth of cave formations such as stalactites and stalagmites. The team also hopes to find microbes that could be exploited for medical, industrial and biotechnology applications.........

Posted by: Tyler      Permalink         Source

October 19, 2006, 9:26 PM CT

Protein That Helps Chickenpox Spread

A team of scientists at the National Institute of Allergy and Infectious Diseases (NIAID), one of the National Institutes of Health (NIH), has identified a human protein that helps varicella-zoster virus, the cause of chickenpox and shingles, spread from cell to cell within the body.

NIAID virologist Jeffrey I. Cohen, M.D., and NIAID research fellow Qingxue Li, M.D., Ph.D., discovered that a surface protein of varicella-zoster virus attaches to a cellular protein called insulin-degrading enzyme, using it as a receptor to enter and infect cells. In the October 20, 2006 issue of the journal Cell, they also describe how interfering with this interaction inhibits the spread of virus among cells in the test tube. The discovery of this receptor is important in understanding varicella-zoster virus, say Drs. Cohen and Li.

Their finding is also an important first step towards designing new therapies for shingles. "If safe and effective ways of disrupting this interaction can be found, eventually new interventions may be developed for treating people with this painful and debilitating disease," says NIAID Director Anthony S. Fauci, M.D.

Shingles occurs only in people who have already had chickenpox. Once chickenpox has run its course, some virus remains dormant in nerve cells at the base of the brain and alongside the spinal cord. With advancing age and diminished immunity, the virus can reactivate years later and travel down the nerve cells to the skin. There it multiplies, causing the blistering rash of shingles and damaging sensory nerve endings. The rash usually heals within a few weeks, but the nerve damage sometimes causes one of the worst complications of shingles--a severe type of pain called postherpetic neuralgia, which can last for months or even years.........

Posted by: Sean      Permalink         Source