Drake University's base program is in the area of life sciences with an interest in addressing astrobiological issues as defined by NASA. The work is focused on training undergraduate students for careers in science. The program successfully integrates teaching approaches that nurture a deep understanding of content-specific knowledge while addressing its application in real-world settings. Through the Drake base program, students develop critical thinking, laboratory, problem solving, oral communication and written communication skills. Projects in the program are concentrated in the area of biochemical, cellular and molecular responses of organisms to extraordinary stress. Research topics include trauma, aging, cancer, apoptosis, and chromosome instability.

The training uses apprenticeship, as well as cooperative-style learning and peer mentoring in a cross-disciplinary and cross-community educational program. Although Drake faculty and their community partners oversee all facets of the projects, students actually conduct the research. All participants (faculty, students, and partners) work as a team to collect, analyze, interpret, evaluate, and present data. We have weekly meetings to discuss research literature, laboratory techniques, experimental results, experimental theory, and upcoming experiments and presentations. Students have presented and will continue to present at an array of regional and national professional meetings. Students are coauthors with faculty on the resulting publications.

This structure allows us to involve significant numbers of students. For example, in the trauma project for year 2002-03, 40 students participated in the various projects, and in 2003-04, 30 students were involved. In 2002-03, student research led to six professional presentations and two publications, all with student authors. The students proceeded into successful postgraduate positions, including medical schools, bioinformatics, MD/PhD programs, medical illustration, epidemiology, graduate programs in biochemistry and molecular biology, and patent law. Their participation in this research was cited as a key component to their preparation for future careers. They also cited the importance of the research as a service to the community.

For more information on the Drake base program contact:
Dr. Charisse M. Buising charisse.buising@drake.edu
Director, Biochemistry, Cell and Molecular Biology Program
Drake University Campus Coordinator, Iowa Space Grant Consortium

Sweat May Impair Skin PCO2 Dependent Discrimination Between Exercise And Injury

Non-invasive discriminators between the physiologic changes caused by exercise (or excitement) and those caused by serious injury could be very helpful at locations with difficult or limited access to definitive medical care (such as outer space or battle fields) and at multiple victim trauma scenes (such as motor vehicle accidents). The partial pressure of CO2 (PCO2) at the skin surface and in exhaled alveolar air (end-tidal air) is available non-invasively and has theoretic reasons to be useful in separating the seriously injured, internally bleeding person from the non-seriously injured person relatively independent of exercise status. The end-tidal PCO2 is determined by blood PCO2, blood flow to the lungs (all of right heart output), and minute ventilation (volume in mL of CO2 containing air being exhaled per minute). Blood PCO2 is determined by CO2 production in the tissues, blood flow through those tissues to pick up the produced CO2, and CO2 removal from the body by the lungs. CO2 production in the tissues is determined by tissue metabolism and the adequacy of tissue blood flow to meet the tissue's demand for oxygen (aerobic CO2 production versus anaerobic, bicarbonate buffering of increasing H+, CO2 production when tissue oxygen delivery is inadequate to meet tissue metabolic needs). Skin cell (live cells of the epidermis and dermis, not the protective but dead diffusion barrier layer known as the stratum corneum) metabolic needs should be relatively unaffected by either exercise or internal injury. Skin blood flow, on the other hand, is increased during exercise as a method to shed muscle generated heat load and decreased with serious blood loss as a method to preserve brain and heart blood flows following serious injury. As we previously determined,1,2 skin PCO2, therefore, should remain parallel with or even become closer to end-tidal PCO2 with exercise and should move away from end-tidal PCO2 with serious blood loss. Since ambient temperature may affect baseline skin blood flow, we investigated the effects of running at three different ambient temperatures on skin PCO2 as monitored with a currently medically used, 37C Severinghaus-type sensor (SensorMedics Microgas 7650®).
Methods: At 60, 70, and 80F, 15 volunteers in shorts and t-shirts followed 30 minutes of no activity with 30 minutes of treadmill jogging at 75% of their calculated maximum heart rates (target heart rate = 0.75 x (217 - (0.85 x age))). Heart rate was monitored with pulse oximetry. Chest skin PCO2 was monitored with a 37C Severinghaus-type sensor while chest skin PO2 was monitored with a Clark-type electrode in the same housing. Respiratory rate and end-tidal PCO2 were monitored with near infrared. Respiratory tidal volumes were measured each 10 minutes.
Results: Variables were stable and unaffected by ambient temperature prior to exercise. Exercise induced increases in tidal volume (902±93mL/breath at exercise start to 1426±124mL/breath after 10 minutes with little subsequent change), respiratory rate, end-tidal PCO2, and skin PO2 were the same for each temperature and have been graphed together. Skin PCO2 responses were variable rather than consistently declining to mingle with end-tidal PCO2 values as had been previously observed with exercise.1 In the graphs, jogging starts at time 0. (±SE)