Friday, September 28, 2007

Plant scientist Richard Jorgensen honored

The American Society of Plant Biologists (ASPB) recently announced the recipients of its 2007 awards, presented at their annual meeting this summer in Chicago, Illinois. Richard Jorgensen, a professor in the UA Department of Plant Sciences, was designated a member of the 2007 inaugural class of ASPB Fellows. Established in 2007, the Fellow of ASPB award is granted in recognition of distinguished and long-term contributions to plant biology and service to the Society by current members in areas that include research, education, mentoring, outreach, and professional and public service. Current members of ASPB who have contributed to the Society for at least 10 years are eligible for nomination.

In addition, Jorgensen received the ASPB Martin Gibbs Medal, presented biennially to an individual who has pioneered advances that have served to establish new directions of investigation in the plant sciences. Jorgensen was honored for his pioneering work leading to the discovery of RNA interference (RNAi). The work on cosuppression and epigenetic gene silencing, conducted in plants by Jorgensen and his coworkers, significantly contributed to the present understanding of the scientific and practical importance of RNAi.

Founded in 1924, ASPB (formerly known as the American Society of Plant Physiologists) has a membership of approximately 5,000 plant scientists from the United States and more than 50 other nations. ASPB publishes two of the most widely cited plant science journals in the world, Plant Cell and Plant Physiology.

[Note: Contact Richard Jorgensen at To learn more, visit]

New leads for cancer drugs

Tumor cells don't play by the rules that other cells have to follow. They grow and multiply unchecked because the mechanisms that regulate cell growth and program cell death have been turned off, making the renegade cells immortal. Cancer researchers are focusing on the role of particular enzymes involved in this biochemical malfunction to find new ways to halt or kill malignant tumors. Generally, enzymes play a key role in the signaling pathways of individual plant and animal cells.

Scientists at the University of Arizona have identified a new series of compounds that can halt the action of a specific enzyme called protein kinase B, also known as Akt, in cancer tumor cells. Their findings have been patented and will soon reach the clinical testing phase for the treatment of patients afflicted with cancer. The research is funded by the National Institute of Health and the Arizona Biomedical Research Commission.

[Note: Contact Emmanuelle Meuillet at To learn more, visit]

Space germs could yield earthly cures

[Source: Phil Berardelli; ScienceNOW] -- Bacteria that have been launched into space become deadlier than their earthbound counterparts, according to a new study. The finding may provide fresh insights on how to combat bugs right here on terra firma. Space agencies around the world are beginning to plan missions to the moon and eventually to Mars and beyond. During those missions, astronauts will be exposed not only to external dangers such as solar radiation and micrometeorites but also to internal hazards such as bacterial infection. For that reason, researchers want to learn more about how bacteria behave in space flight. For example, does weightlessness affect microscopic organisms in the same way it does humans and other living creatures?

To find out, researchers sent samples of Salmonella typhimurium, a common infectious bacterium used in lab studies, aboard the space shuttle Atlantis for 12 days in September 2006. They performed detailed genetic and protein-expression analyses on the Salmonella samples after the specimens returned to Earth. Reporting online this week in Proceedings of the National Academy of Sciences, the team found that after a 2-week stint in space the microbes were three times more able to kill infected mice than were control samples that remained on the ground. The flight also changed the expression of 167 of the bacterium's genes, including one for a protein called Hfq, which could be the key molecule responsible for the increased virulence.

Microbiologist and lead investigator Cheryl Nickerson of Arizona State University in Tempe says the Salmonella's increased virulence is easily treated by antibiotics, but what's important about the study is that it revealed the cause of the change: The low gravity led to a condition called low fluid shear, in which the bacterium's liquid environment reaches a gentle but not absolutely still state, similar to what the bug encounters inside the body during infection. When the scientists duplicated low fluid shear in lab experiments on the ground, the Salmonella samples acted in many of the same ways they did aboard Atlantis. This insight should give researchers new ways to design therapies that could disrupt the Hfq protein and perhaps stop infectious agents like Salmonella dead in their tracks, says Nickerson. "We've [now] got a tremendous amount of data" on how low fluid shear affects bacterial responses, she says.

Space bioscientist Lynn Harper of NASA's Ames Research Center in Moffett Field, California, agrees that the findings hold promise. The study provides solid evidence for medically important phenomena that were only hinted at in prior research, she says: "There is increasing evidence that space can provide important new tools for learning to fight certain diseases."

Thursday, September 13, 2007

UCLA/VA partners with ASU to advance biosensor technology for urinary tract infections

[Source: Eureka Alert] -- NIH award will help team develop a faster, more sensitive product to test for infection. Researchers from the David Geffen School of Medicine at UCLA, the Veterans Affairs Greater Los Angeles Healthcare System, GeneFluidics Inc. and the Biodesign Institute at Arizona State University have received a five-year, $3.2 million award from the National Institutes of Health to help rapidly diagnose and treat urinary tract infections — the most common cause of hospital-associated infection in the United States. The initiative brings together academic and industry leaders to further advance a groundbreaking technology — initially developed by UCLA/VA researchers and corporate partner GeneFluidics — that allows for rapid, species-specific detection of bacteria in human clinical fluid samples using a microfabricated electrochemical sensor array.

Joe Wang, director of the Biodesign Institute’s Center for Bioelectronics and Biosensors, will join the collaboration to improve the performance of the test by dramatically enhancing its sensitivity and speed. Wang has more than 25 years of success in biomedical applications and a strong track record of bringing similar sensors, used for glucose monitoring, to the market. “We are extremely fortunate to have Joe Wang and the Biodesign Institute as partners in this endeavor,” said principal investigator Dr. David Haake, professor of medicine at UCLA and an infectious diseases specialist at the VA. “Biodesign’s expertise will make it possible to quickly bring the electrochemical sensor to clinical reality. Working together, we hope to fundamentally change the way antibiotics are selected for the treatment of infectious diseases.”

“The goal of our collaborative effort is to develop all of the technical components to produce a biosensor that can rapidly and reliably identify a bacteria and its spectrum of antibiotic susceptibility to aid point-of-care diagnostics for the clinic,” Wang said.

Industrial partner GeneFluidics will help deliver a custom-built, fully functional prototype, called PATHOSENSE, within the time frame of the grant. At the conclusion of the grant period, the team hopes to work with GeneFluidics for near-term deployment of the PATHOSENSE instrument in multicenter clinical testing. “By combining our expertise, we will be able to bring outstanding pathogen screening products to health care professionals,” said Dr. Vincent Gau, president of GeneFluidics. “Using GeneFluidics’ proprietary electrochemical platform as the backbone of our tests allows for very high sensitivity and for a streamlined system that delivers antibiotics resistance results in record time — two hours instead of two-to-three days.”

The technology relies on the ability to detect the genetic signature of a bacterial pathogen. The researchers will use 16S rRNA, a ribosomal molecule found in all bacteria, to identify the bacteria species. The research team will focus on enhancing the performance and validation of the electrochemical biosensor assay and will develop an antimicrobial susceptibility test to rapidly select the best antibiotic for treatment. “Our mission is to create a new technology to solve an old problem, which is the diagnosis of urinary tract infections — the second most common bacterial infection — in a clinically relevant time frame,” said Dr. Bernard Churchill, chief of pediatric urology at the Clark-Morrison Children’s Urological Center at UCLA.

In current laboratory practice, pathogens in urine specimens are grown in culture dishes until they can be visually identified. The major drawback of this century-old technique is the two-day time lag between specimen collection and bacteria identification. As a result, physicians must decide whether to prescribe antibiotic therapy and, if so, which antibiotic to use — all without knowing the actual cause of the infection, if any. In contrast, the new biosensor technology would allow physicians to prescribe targeted treatment without the wait.

Urinary tract infection is the most common urological disease in the United States and the most common bacterial infection of any organ system. It is a major cause of patient death and health care expenditures for all age groups, accounting for more than 7 million office visits and more than 1 million hospital admissions per year. Catheter associated urinary tract infection accounts for 40 percent of all hospital-acquired infections — more than 1 million cases each year. The total cost of urinary tract infections to the U.S. health care system in 2000 was approximately $3.5 billion. The grant is funded by the National Institute of Allergy and Infectious Diseases, a branch of the National Institutes of Health.