Researchers silence genes with new approach

Researchers have developed a way to exploit RNA interference for the first time to silence genes in a wide variety of mammalian cells, including embryonic cells. The study will appear in the Feb. 17 edition of Nature Genetics. This new approach allows genes to be switched off by inserting short pieces of ribonucleic acid (RNA) into developing cells. It is currently being used to help researchers uncover the function of the more than 30,000 genes found in humans, as well as in animal models of important diseases.

February 20, 2003

Los Alamos lab to filter nearby river for chemical, radioactive waste

Water flowing through Mortandad Canyon downstream of Los Alamos National Laboratory operations now will flow through a Permeable Reactive Barrier — a huge column of pollution-capturing materials — before proceeding farther downstream. Waters that encounter the PRB will be scrubbed of radionuclides such as strontium-90; americium-241; plutonium 238, 239 and 240; and uranium isotopes as well as chemicals such as perchlorate, nitrate and heavy metals. Mortandad Canyon is the location of the effluent stream from the Laboratory’s Radioactive Liquid Waste Treatment Facility. The RLWTF discharges about 60,000 gallons of treated effluent per week on average.

February 20, 2003

Duke Implements Additional Transplantation Safeguards

As a result of a blood type mismatch that occurred during the Feb. 7, 2003 heart-lung transplant for Jesica Santillan, Duke University Hospital has implemented additional safeguards that will improve the safety of the organ transplantation process.
“Every effort is being made to save Jesica’s life,” said William Fulkerson, M.D., CEO of Duke Hospital. “Our primary concern has always been for Jesica and her family. This was a tragic error, and we accept responsibility for our part. This is an especially sad situation since we intended this operation to save the life of a girl whose prognosis was grave. Jesica continues to remain at the top of the national organ donation list.

Eds: Jesica Santillan received a new heart transplant that was reportedly functioning unaided Thursday afternoon.

February 20, 2003

Scientists locate, characterize key hormone involved in appetite control

Researchers have identified a key hormone involved in appetite control and demonstrated its effect on the brain. Scientists have shown that the hormone, called ghrelin, activates specialized neurons in the hypothalamus involved in weight regulation. Researchers believe this information could be used to develop drugs aimed at stimulating appetite in patients who have undergone extreme weight loss due to illness, a condition known as cachexia. Conversely, drugs aimed at limiting production of the hormone might be developed to reduce appetite for those battling severe obesity.

February 20, 2003

Fly mutation suggests link to human brain disease

Greater insight into human brain disease may emerge from studies of a new genetic mutation that causes adult fruit flies to develop symptoms akin to Alzheimer’s disease. “This is the first fruit fly mutant to show some of the outward, physical manifestations common to certain major human neurodegenerative diseases,” said principal investigator Michael McKeown, a biology professor at Brown University. A research team found the mutation in a gene they named “blue cheese.”

February 20, 2003

Aircraft technology helps diagnose artificial hip, knee problems

To assess the wear and tear on jet engine parts, mechanics used an old technology called ferrography to run the aircraft’s lubricating fluid through a magnetic device to separate out metal shavings and other ferrous engine debris. A University of Rhode Island researcher uses a similar process to assess the wear and tear on artificial hip and knee joints so patients can reduce the number of follow-up surgeries they must undergo or reduce the time spent in revision surgery.

February 20, 2003

Alcohol Researchers Identify a Genetic Basis of Pain Response

A common genetic variant influences individual responses and adaptation to pain and other stressful stimuli and may underlie vulnerability to many psychiatric and other complex diseases, reports David Goldman, M.D., Chief, Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, and colleagues at NIAAA and the University of Michigan. COMT val158met Genotype Affects m-Opioid Neurotransmitter Responses to a Pain Stressor appears in the February 21 issue of Science.

February 20, 2003

Bidis, other smoking products no safer than conventional cigarettes

Studies published over the past several months disprove claims that products such as additive-free cigarettes, bidis, and novel cigarette-like devices are less toxic than conventional cigarettes. A study published in the December 2002 issue of the journal Nicotine and Tobacco Research examined the effects of bidis–hand-rolled cigarettes from India–and additive-free American Spirit cigarettes. Bidis are popular with adolescents because many perceive them to be less of a risk to health than regular cigarettes, and because they are manufactured in a variety of flavors, such as chocolate or root beer.

February 20, 2003

Self-control comes in limited quantities, must be replenished

Self-control, whether used to pass up the office cookie plate or to struggle against temptations like alcohol and tobacco, operates like a renewable energy source rather than a learned skill or an analytical thought process, according to new research.
Individuals had less physical stamina and impulse control and increased difficulty with problem-solving activities after completing a variety of tasks that required some measure of self-control, according to Roy F. Baumeister, Ph.D., of Florida State University.

February 19, 2003

Surgeons put themselves at risk, despite evidence

Exposure to blood and body fluids while operating places surgeons at risk, yet a large number of doctors continue to put themselves in danger despite knowing the evidence, according to a University of Alberta study. Double gloving is a safety measure, which decreases the risk of exposure. However, many surgeons do not incorporate this precaution into their personal practice. This study, which is published in the current edition of the American Journal of Surgery evaluates surgeons’ gloving practices and hepatitis status.

February 19, 2003

Electronic Circuit Rides a Chemical Film

Chains of molecules known as conducting polymers are versatile materials that can work like electronic circuits. Potential uses include flat panel displays, solar panels, sensing devices and transistors, to name just a few. Their invention won three scientists the Nobel Prize in chemistry. But to make useful devices from conducting polymers requires a degree of chemical wizardry that often proves elusive. A Chicago chemistry professor has found a new and effective way around the problem.

February 19, 2003

Bt found to kill parasitic roundworm

Biologists at the University of California, San Diego have discovered that Bacillus thuringiensis, or Bt — a bacterium that produces natural protein insecticides that have been used by organic farmers for five decades — can also produce similar natural proteins that kill nematodes. The discovery could pave the way for the development of an inexpensive and environmentally safe means of controlling the parasitic roundworms that each year destroy billions of dollars in crops, cause debilitating diseases in farm animals and pets, and now infect a quarter of the world’s human population.

February 19, 2003

Study finds addictive drugs all tweak same neurons in brain

Drug addicts may prefer some drugs over others, but their brains all have something in common. Whether it’s uppers or downers, addictive drugs tweak the same addiction-related neurons, causing them to become more sensitive, say researchers at Stanford University Medical Center. “What we have identified is a single change caused by drugs of abuse with different molecular mechanisms,” said researcher Robert Malenka.

February 19, 2003

Normal nerve cells can mimic viruses

A Montreal researcher has discovered that nerve cells can bypass the body’s normal protein-making machinery in the same way that viruses do when they infect a cell. Why would they? To produce large quantities of a particular protein under certain physiological conditions.

February 19, 2003

'Periodic Table' of proteins helps make sense of structure

Scientists at the University of California, Berkeley, and Lawrence Berkeley National Laboratory have taken the first stab at a “periodic table” of the protein structures – an organized map of the building blocks used over and over again to construct the billions of complex proteins that make up life on Earth. The three-dimensional map depicts similarities and differences among the building blocks, letting scientists visualize the universe of possible protein structures – the many possible twists, turns and folds – and see evolutionary changes that may have occurred with time.

February 19, 2003