Technology Bulletin 243

Bone paste promises castless union

A new "bone paste" that can be injected directly into bones, where it hardens in minutes, could dramatically improve treatment for the more than 1.5 million Americans who break their bones every year. The material, called Norian SRS, becomes as strong as real bone about 12 hours after injections, says its inventor, Brent R. Constantz, CEO of the Norian Corp., Cupertino, CA. Now under trial nationwide, the material can hold together splintered bones, fill gaps in bones caused by osteoporosis, or reinforce metal plates and screws used for severely broken bones. When injected into broken bones, Constantz explains, SRS becomes "completely interpenetrated" with the bone. When the bone-destroying cells begin to secrete acid to eat away bone, the acid also eats away the SRS, effectively ridding the body of the foreign substance. The material, Constantz believes, has significant advantages over other bone "glues" now in use. One, called PMMA (polymethylmethacrylate), has proved highly useful in joint replacement surgery, but less effective for broken bones. Ceramic products and injections of ground-up bone tissue from the patient's body do not provide the strength and structure the SRS apparently can. FAX (408) 252-3355.

Painless intracranial pressure measures tested

Scientists at NASA's Ames Research Center, Mountain View, CA, have under test two diagnostic devices to measure pressure inside the head, or intracranial pressure (ICP)-without penetrating the skull or skin. If successful, the tests would help determine whether increased ICP contributes to headaches, nasal congestion, and space motion sickness. One device, developed by Dr. John Cantrell and Dr. Tom Yost at NASA's Langley Research Center, transmits an ultrasound wave through the front of the skull to a small disk secured to the forehead. The wave passes through the brain tissue, reflects off the opposite side of the skull, and is received by a sensor in the disk for measurement. The second technique uses a very light mechanical stimulus applied to the forehead that is transferred through the skull and received by sensors on the scalp. Changes in pressure inside the head can be measured by examining changes in the response signal. Scientific Atlanta of Atlanta, and CytoProbe Corp., San Diego, developed this system. FAX Ann Hutchison at (415) 604-6999.

Spider silk could replace torn ligaments

An athlete with a torn ligament receives an artificial ligament in an operation that leaves no scar. Several weeks later, the athlete is back on the field with a knee as strong as before. Such an operation could become routine one day, according to Randy Lewis, a professor of molecular biology at the University of Wyoming Laramie. The creature that could make this possible: the spider. Spiders produce different kinds of silk. Lewis has singled out dragline silk that spiders use for the outer framework of their webs for his work. Gram for gram, Lewis says, dragline silk's tensile strength is greater than that of steel. Lewis has isolated the two proteins that make up the silk. They are somewhat unique in how they are held together. While most proteins are bonded with chemical links, spider-silk proteins have a physical bond, making the silk virtually impervious to water. His efforts have led to several offshoots of his research, including four possible patents. FAX (307) 766-5198.

Genetic form of Parkinson's disease identified

Until now, little was known about the source of Parkinson's disease, a progressively disabling illness that affects roughly one million Americans. A disease of the central nervous system, it causes slow movement, muscle rigidity, and tremors. In its most progressive state, it robs patients of their ability to function independently. Researchers at the Washington University School of Medicine in St. Louis recently identified a rare genetic form of Parkinson's disease, caused by a gene mutation that creates abnormal iron accumulation in the brain. The finding provides one of the first insights into the cause of the illness. "This is a clearly defined piece of the puzzle, and there haven't been many of those in this particular disease," says Jonathan Gitlin, associate professor of pediatrics and the primary investigator. Gitlin and his colleagues discovered the genetic form of the disease when studying patients in Japan that had Parkinson's symptoms and low levels of ceruloplasmin. With radiographic imaging and tissue biopsy, they found these people had abnormal iron accumulation in the basal ganglia region and in their livers. Gitlin's lab obtained DNA from some of the patients and identified a mutation on the gene. FAX Susan M. Killenberg at (314) 935-4259.

Parallel computer pursues surgical breakthroughs

Rensselaer Polytechnic Institute, Troy, NY, has purchased a powerful 36-processor IBM Scalable POWERparallel system in an attempt to develop new surgical techniques. Research currently underway includes a collaborative effort with Columbia University to understand the relationship between bones and joints in the human body. The Rensselaer scientists use the IBM SP2 to recreate and help analyze the behavior of soft tissue in the body as the joint moves. "Currently, surgeons have a very limited idea of what the stresses are inside a joint; they rely primarily on feedback from the patient, because this stress results in pain," explains Dr. Mark Shephard, director of the Scientific Computation Research Center. FAX (518) 276-4886.

Traveling ions could hold key to many diseases

In another Rensselaer Polytechnic Institute project, Leah Frye, an associate professor of chemistry, hopes her work with ions will help scientists better understand cystic fibrosis, epilepsy, and other common diseases. Scientists already know that the most common method of ion transport takes place through channels in the membrane that surrounds the cell. Through these channels, ions, such as sodium cations, are transported into and out of cells. Disease may result when ion channels malfunction or are improperly formed from the start. Frye and her researchers have produced "biomimetic" channels that transport odium ions across membranes they can see using nuclear magnetic resonance spectroscopy. The next step: perfecting the artificially produced ion channels to increase or retard the selective transport of ions. FAX (518) 276-6091.

Bar-codes automate medication dispensing

Two of the nation's leading health-care companies have joined forces to develop a new packaging process for dispensing medications. Automated Healthare, Inc., Pittsburgh-based maker of a hospital pharmacy robotics system, and UDL Laboratories, the Rockford, IL supplier of generic pharmaceuticals, recently unveiled the bar-coded Robot Ready(TM) system for the institutional marketplace. The packaging program integrates bar coding at all levels of a hospital's unit dose medication handling process. Its makers claim that the system not only will save millions in dispensing costs, but will prevent medication errors. The robot uses the bar-code technology not only to automate medication dispensing, but for stocking, inventory control, restocking, and crediting applications. FAX (412) 967-3599.

Acrophobia undergoes virtual reality therapy

An experimental therapy based on virtual reality (VR) computer simulations has helped persons with acrophobia reduce their fear of heights. The research, the work of a team of computer scientists and clinical psychologists, is believed to be the first study of the use of VR for treating a behavioral disorder. Dr. Larry F. Hodges, an associate professor in the College of Computing at the Georgia Institute of Technology, headed the research team. In a series of sessions conducted by a clinical therapist, the treatment group used head-mounted VR displays to view a series of anxiety-producing scenes from bridges, balconies, and an open glass hotel atrium elevator. In each case, the subjects began at ground level and moved gradually higher in the simulated scene-until they showed or reported signs of distress. The subjects remained at that level until their anxiety levels dropped. Ultimately, all the test subjects mastered the three environments, including what became known as the "Indiana Jones" bridge suspended a simulated 80 meters above a river. FAX (404) 894-6983.

Defense spinoff helps babies at respiratory risk

On the battlefield, real-time data fusion and control systems technologies routinely integrate information from radar, optical sensors, and personnel to make tactical decisions. Now, a team of researchers at Pennsylvania State University's Applied Research Laboratory and the Hershey Medical Center hope to spin off those technologies in an attempt to improve the care of premature infants with respiratory distress syndrome. In the neonatal intensive care nursery, the researchers believe, these technologies can be used in an automated system that continuously monitors at-risk babies' oxygen levels, then automatically delivers oxygen tailored to each baby's needs. The system, now under development, would also recognize sensor failure and other dangerous situations that require input from nurses or doctors. The prototype will include as its primary sensor a non-invasive pulsatile oxygen analyzer, which estimates the percent of oxygen saturation of hemoglobin in the blood. It performs this task by pulsing light into the skin and measuring how much of the light is absorbed at two specified frequencies. FAX (814) 863-0753.

Researchers develop instant "window" into body

Medics on a battlefield or paramedics in a remote setting all face the same race to save those suffering from internal injuries. In an attempt to decrease the time it takes to get critical information to physicians, officials from the Madigan Army Medical Center, Fort Lewis, WA, and the Pacific Northwest Laboratory, Richland, WA, will team to develop a portable imaging system that would use acoustic waves to locate and monitor internal injuries. The device would provide real-time, three-dimensional images to immediately assess biological damage-such as internal bleeding-from trauma or to locate bullets or other fragments. The imaged data would be digitized and transmitted to off-site physicians in an effort to provide specialized care to patients at remote locations. FAX (509) 375-2242.