Author Archives: Chelsea Behymer

Over sixty years digging and we’re still finding new ‘dirt’ on HJ Andrews

One kilometer. Or roughly ten football fields. That’s the extent of the area over which Karla Jarecke, a Ph.D. candidate in the College of Forestry’s Department of Forest, Ecosystems & Society can feasibly navigate her way through the trail-less HJ Andrews Experimental forest to collect the data she needs in a typical day of field work. Imagining a football field is perhaps not the best way to appreciate this feat, nor envision the complex topography that makes up this coniferous forest on the western flanks of the Cascade mountains, roughly 50 miles East of Eugene. But these characteristics are precisely what have made this forest valuable to scientists since 1948 and continue to make it the ideal place for Karla’s research.

Experimental watersheds like the HJ Andrews forest were established initially to understand how clear-cutting influenced forest drainage and other ecosystem processes such as regrowth of plants and change in nutrients in soils and streams. This was during the time when timber-take was increasing and we still had little understanding of its ecosystem effects. Karla’s work is also forward-thinking, but less on the lines of what will happen to drainage when trees are removed and more focused on understanding the availability of water for trees to use now and in the future. She wants to know what influence topography has on plant water availability in mountainous landscapes.

Meter deep soil pits at Karla’s field site.

Back to bushwhacking. The answer to Karla’s research question lies beneath the uneven forest floor. Specifically, in the soil. Soil is the stuff made up of weathered rock, decomposing organic material and lots of life but it is also the medium through which much of the water within a forest drainage moves. Across her study area, Karla has 54 sites where she collects data from sensors that measure soil moisture at two different depths. These steel rods send electrical currents into the ground, which depending on how quickly they travel can tell her how much water is present in the soil. She also keeps track of sensors that measure atmospheric conditions, like temperature and air humidity. This information builds on the incredible sixty-year data set that has been collected on soil moisture within HJ Andrews, but with a new perspective.

Digging soil pits on steep slopes occasionally required stacking logs at the base of a tarp to prevent the soil from sliding down the hill.
Photo credit: Lina DiGregorio

Karla explains that there have been long-standing assumptions surrounding elevation gradients and their control on water availability in a forest system. This understanding has led to modeling tools currently used to extrapolate soil moisture across a landscape. But so far, her data show huge variability on surprisingly small scales that cannot be explained by gradient alone. This indicates that there are other controls on the spatial availability of soil moisture in such mountainous terrain.

“We’re finding that model doesn’t work really well in places where soil properties are complicated and topography is variable. And that’s just the first part of my research.”

The next phase of Karla’s work seeks to evaluate tree stress in the forest and determine if there are any connections between this and the variability she is finding in soil moisture across spatial scales. True to the complex nature of the landscape, this work is complicated! But to Karla, it’s important. Growing up in the mid-west, Karla came to know water as “green” and when she moved West, first to fulfill an internship in Colorado and then to pursue her graduate work here in the Pacific Northwest, she was (and still is) amazed by the abundance of clean, clear rivers and streams. And it’s something she doesn’t ever want to take for granted.

Karla and her sister Stephani snowshoeing on Tumalo Mountain in the Cascade Range of central Oregon.

To find out more about Karla’s research and her journey from farming in Italy to studying soil, tune in on Sunday, October 27th at 7 PM on KBVR 88.7 FM, live stream the show at http://www.orangemedianetwork.com/kbvr_fm/, or download our podcast on iTunes.

Giving therapy-resistant cancer cells a taste of their own medicine

The use of chemotherapy to fight various forms of cancer in the human body has been a successful method for decades, but what happens when it fails? This question strikes a personal note for Martin Pearce, a Ph.D. candidate in the Department of Environmental and Molecular Toxicology at Oregon state University. Prior to his graduate work, both of his grandmothers were diagnosed with breast cancer. One successfully went through treatment and although the other initially responded well to chemotherapy, years later the cancer cells reappeared and there was no other treatment available.

Martin in the lab, running one of many Western Blots.

The academic system in the United Kingdom, from where Martin hails, encourages undergraduate students to take what is termed a “placement year” between their second and third years to gain practical experience. At the time of his grandmother’s returning prognosis, Martin was in the second year of his studies at University of the West of England Bristol which had a connection with East Carolina University in the States. Although deviating somewhat from his initial advanced level courses in business, the opportunity to work full time in a biomedical sciences lab at a university renowned for its medical research provided just the right place for Martin to spend the following year.

Martin’s time in North Carolina was not only practical but a reminder of his experience with biology in secondary school. His teacher was a doctor and she encouraged him to pursue a career in a biomedical field. While biology wasn’t his easiest subject, Martin was inspired by his mentor and enjoyed the challenge. Today, he is fully committed to this challenge as a key member in Dr. Siva Kolluri’s Cancer Biology lab group at Oregon State University researching new strategies to target the cancer cells that continue to grow after treatment with chemotherapeutic agents.

Current members of Dr. Siva Kolluri’s Cancer Biology Laboratory group.

Their work involves screening tens of thousands of compounds against such resistant cancer cells that express a particular group of proteins called the Bcl-2 family of proteins. The lab has discovered a novel compound that binds specifically to the Bcl-2 family of proteins that are consistently expressed in therapy-resistant cancer cells and cause them to change shape. One of the fundamental principles of cell and molecular biology is the relationship between structure and function. Change the structure of a molecule and its function within a cell can completely transform. In the case of the Bcl-2 family of proteins, this literally means life or death for the cell.

Protected within the typical expression of a Bcl-2 protein is a region Martin describes as a “death domain”; if this domain is exposed, it induces cell death. Cell death or ‘apoptosis’ is a naturally occurring process in biology. Without apoptosis in the early stages of human development, we would all have webbed fingers! Martin and his team have discovered a compound capable of binding to a Bcl-2 protein, causing it to unfold and expose its death domain. Thus, the protein transforms from one that protects the resistant cancer cell into one that kills it.  

Example of Breast cancer cells that are resistant to chemotherapeutic agent Taxol, that are responsive to compound Bcl-2 Functional Converter (BFC). Blue dots are cancer cell colonies.

Demonstrating the effectiveness of this pathway at the cellular level is remarkable, but Martin explains even the years it has taken to reach this stage are just the beginning of a very long process until it can be used to treat people with cancer. Beyond discovery, through the work of his Ph.D. Martin has realized other critical steps in developing effective cancer treatments that occur outside of the lab. For example, once a compound has been identified that successfully binds to a target protein, medical researchers must work with a patent attorney to protect their work and generate funding. Without patent protection, new drugs can’t be developed.

The dedication to ‘translational research’ or science that is specifically designed to be applied in improving health outcomes is what drew Martin to work with Dr. Kolluri in the first place and continues to inspire his plans for the future. Drawing back to his early interest in business, after finishing his Ph.D., Martin intends to explore a career as a patent attorney.

“This way I can be involved in the most exciting part of the process for me and be a part of people being at the edge of achieving what I was initially inspired in this career to achieve.“

Lifelong Bristol City F.C. supporters, Martin and his dad at Ashton Gate Stadium.

To hear more about Martin’s graduate work and insights into translational research, tune in on Sunday, October 13th at 7 PM on KBVR 88.7 FM, live stream the show at http://www.orangemedianetwork.com/kbvr_fm/, or download our podcast on iTunes!