Page top
Skip navigation



2005-2006 HIGHLIGHTS








Cover of the 2006 Annual Report
Annual Report

PDF (10 MB)
Cover of the 2006 College Directory
College Directory

PDF (5 MB)


Content begins

Kristyn Masters and Karien Rodriguez

Biomedical Engineering

Studying the keys to heart disease

To learn about the mechanisms that cause heart valve disease and to design functional valve replacements, Assistant Professor Kristyn Masters (left) and graduate student Karien Rodriguez are studying how heart valve cells interact with their extracellular environment. The knowledge, she says, is key to designing effective bioactive materials—those that instruct the cells—that form the basis for tissue-engineered heart valves.

With her $400,000 National Science Foundation CAREER award, Masters is studying heart valve cells known as valvular interstitial cells, or VICs. Already she has learned that VICs are very responsive to both the mechanics and protein composition of their environment.

As a result, she says, the types of extracellular matrices and protein environment present for VICs can tell VICs whether or not to become diseased. “We can actually form calcification in our in vitro cultures,” she says. “And calcification is one of the main causes of native valve failure—it becomes so stiff that it won’t open right or close right.”

In engineered tissue, proteins and material stiffness also dictate how diseased or calcified VICs become, says Masters. On material surfaces, cells appear flat and spread out. They use intracellular fibers to grip or pull those materials. The stiffer the material, the harder the cell pulls—and there is growing evidence that how much the cell pulls on the material correlates to how many disease-related factors it produces. “This pulling can actually initiate this disease program within the cell,” says Masters.

Although her research focuses on how material properties and the extracellular matrix regulate heart valve disease, Masters says the results also could uncover how heart disease occurs—and point to ways to block it.

Four Coulter researcher-physician projects funded

The University of Wisconsin W.H. Coulter Translational Research Partnership in Biomedical Engineering oversight committee has selected its first-year research projects for funding.

Assistant Professor Kristyn Masters and neurological surgery postdoctoral trainee Roham Moftakhar will collaborate on the project, ”Bioactive spherical aneurism occlusion device.” Professor Ray Vanderby (also engineering physics and orthopedics and rehabilitation) and Orthopedics and Rehabilitation Assistant Professor Lee Kaplan will collaborate on the project, “Acoustoelastic analysis of ultrasound waves to determine in vivo tissue strains and material properties.”

Associate Professor Walter Block (also medical physics) and Radiology Assistant Professor Richard Kijowski will collaborate on the project, “Rapid 3-D MRI cartilage assessment,” and Assistant Professor William Murphy (also pharmacology) and Associate Professor Ben Graf (also orthopedics and rehabilitation) will collaborate on the project, “Biologically active coatings on  bioresorbable orthopedic implants.”

The Coulter Translational Research Partnership in Biomedical Engineering fosters early-stage collaborations between University of Wisconsin biomedical engineering researchers and practicing physicians. These collaborations will enable researchers to deliver advances more quickly to patients. Each project will receive approximately $120,000 for a year.

UW-Madison is one of only nine biomedical engineering departments nationwide selected in the partnership. Often envisioning a commercial product at a research project’s inception, biomedical engineers engage in translational research when they focus on developing practical solutions that address particular problems or unmet clinical needs.

The Biomedical Engineering Center for Translational Research promotes these efforts across the College of Engineering by encouraging practicing physicians to collaborate with engineers in such projects. The center actively develops partnerships, cultivates new translational research projects based on clinical practice needs, identifies and supports promising biomedical engineering collaborative research projects, and rapidly translates solutions into the clinic by fully using UW-Madison campus resources for technology transfer and commercialization.

New MR technique quickly builds 3-D images of knees

A faster magnetic resonance imaging (MRI) data-acquisition technique will cut MR scan time, yet deliver more precise 3-D images of patients’ bodies. The faster technique will enable clinics to image more patients—particularly the burgeoning group of older adults with osteoarthritis-related knee problems—and can help researchers more rapidly assess new treatments for such conditions.

To capture an image, an MR scanner commonly conducts hundreds to thousands of smaller “experiments,” or encodings, that help to make up the big picture. Associate Professor Walter Block’s new data-acquisition technique capitalizes on recent hardware advances that, coupled with a clever way of maintaining a high-level MR signal throughout the scan, will speed an MRI session. “But to maintain the high-level signal, you need to be able to complete each of these smaller encodings within a couple of milliseconds,” says Block.

Rather than using the conventional Cartesian raster method, which sweeps horizontally to gather data, Block’s technique acquires the body’s signals radially, in a way that looks somewhat like a toy Koosh ball. “We can essentially acquire data during the whole experiment, where in the Cartesian case, a lot of time was spent either prepping for the experiment or returning it to the steady state so that you could do the next experiment,” he says.

The technique, which Block patented through the Wisconsin Alumni Research Foundation, also will make it easier to image parts of the body, such as the heart or abdomen, in which motion is a factor.

In related research, Block also has developed an algorithm that, within less than a second, can calibrate an MR system to use non-conventional methods of data acquisition, yet produce clearer images.

Grants from the National Institutes of Health, the UW-Madison W.H. Coulter Foundation Translational Research Partnership, and the UW-Madison Graduate School fund Block’s research.

Back to page topEnd of page