Category: 2012

Oregon Health and Science University: A foundation to build upon. “Envisioning a multifunctional urban campus oriented around pedestrian experience and context connections

Presenter: Jonathan Haller

Mentor: David Hulse

PM Poster Presentation

Poster 12

This is a final comprehensive project for the BLA program, focusing on the design of a medical school campus. The design explores the campus from an urban scale down to detailed focus areas where elements are explored at a fine grain. The methods used break down the design into simple diagrams and build it up to a more complex level of understanding. The project looks at the design from multiple lenses and approaches. The result is a comprehensive look at how a campus is designed and presented in a way for people to understand the design intent. This project is successful in that it has a significant amount of resolution in the time frame of the project. OHSU is a critical part of Portland’s South Waterfront district and this design communicates how the city can benefit from this design as a model for how urban spaces can function.

Autistic Tendencies and Visual Processing: A Local Bias versus a Global Deficit

Presenter: Melissa Dollar

Mentor: Paul Dassonville

PM Poster Presentation

Poster 10

Past research suggests that individuals with autism spectrum disorders (ASD) exhibit an enhanced locally-oriented processing bias, but have an attenuated tendency to use global contextual cues. In addition, the autistic trait of systemizing has recently been found to predict sensitivity to global contextual cues, where high systemizing tendencies are associated with a decreased tendency to pro- cess misleading global context (e.g., visual illusions.) It is currently unclear, however, whether individuals with heightened systemizing drives, such as those with autism, display the same decreased tendency to process context when it provides information beneficial to performance. The current study examined the extent to which systemizing tendencies were predictive of whether individuals could use beneficial global-contextual information in two perceptual tasks. For two different visual tasks we found a significant benefit of the presence of an upright frame (compared to no frame), and no correlation with the autism and systemizing quotients and the extent to which participants benefited from the global context of the frame. These results suggest that individuals with heightened systemizing drives, such as those with autism, can still utilize global information when it is beneficial to performance.

A New Model for Cutaneous Thermal Hyperemia

Patricia Choi, Naoto Fuji and Vienna Brunt

Mentor: Christopher Minson

PM Poster Presentation

Poster 8

Currently, assessment of cutaneous thermal hyperemia is done by locally heating the skin from a baseline of 33 to 42C at a rate of 0.1oC/1 s. The purpose of this study was to characterize the hyperemic response using different rates of heating from the traditional protocol, specifically 0.1oC/1s, 0.1oC/10s, 0.1oC/60s, and three target temperatures, 36, 39, 42 oC. Six subjects (3 males and 3 females) within the age group of 22-25 participated in all six protocols. Skin sites were locally heated on the forearm from a baseline of 33oC to three target temperatures at each of the three rates. After an hour of maintaining the target temperature, the three sites were heated to 43.5 oC to attain maximal skin blood flow (SkBF). SkBF was measured with Laser Doppler flow metery. Data are presented as % maximal cutaneous vascular conductance (CVC),which equals blood flow divided by mean arterial pressure. The new protocol attenuated plateau CVC from 95.3 ± 3.22% of the standard protocol to 33.8 ± 2.69% with 36 C at 0.1C/1s (p< 0.01), 53.7 ± 1.3% with 39C at 0.1C/s (p < 0.01), 29.6 ± 1.5% with 36C at 0.1C/10s (p< 0.01), 45.9 ± 1.7% with 39C at 0.1C/10s (p< 0.01), 25.47 ± 1.3% with 36C at 0.1C/60s (p< 0.01). We suggest that heating at different rates and to target temperatures from the standard heating protocol exhibit different hyperemic profiles.

Pace of Early Epiphyseal Fusion in Captive Macaca

Presenters: Samantha Buckley and Sarah Walker

Mentor: Frances White

PM Poster Presentation

Poster 6

Epiphyseal fusion is an important developmental indicator in all mammals. Among cercopithecids, the sequence of epiphyseal fusion is known but the pacing of these fusions is uncertain. The pace at which the fusion occurs is a window into the growth of an animal that the fusion sequence alone cannot provide. The pace and sequence of epiphyseal fusion in long bones are reported here from a sample of 23 Macaca mulatta from the UO Grand collection, consisting of captive juveniles of known age. We scored 33 epiphyses on 25 bones, including all major long bones, the pelvis, and metapodials. We scored the epiphyses as “0” if there was no fusion, “1” if the joint is fusing, and “2” if the epiphysis has completely fused to the diaphysis. All specimens were scored by two coders to ensure intercoder reliability. Only scores with full agreement were included. Because we scored epiphyses in the process of fusing, we are able to comment on the pace of fusion within M. mulatta more than previous studies. Results indicate that metapodial fusion has begun by birth, but continues to fuse until 60 months. Our only explanation for their typical exclusion from fusion charts is because metapodials fuse so early. Addi- tionally, by twelve months, five other epiphyses have begun to fuse: proximal and distal humeral epiphyses, proximal tibia, femoral head, and the greater trochanter. Our results agree with those previously reported by Cheverud (1981). Our sample is younger, allowing us to add new data especially on metapodial fusion.

Histological Characterization of Changes in Skeletal Muscle during Tourniquet Induced Ischemia and Reperfusion

Presenters: Aaron Boothby and Arman Ameripour

Mentor: Hans Dreyer

PM Poster Presentation

Poster 4

Orthopedic surgeons often utilize a tourniquet during surgical procedures to minimize blood loss and to maintain a clear surgical field. Current clinical dogma is that tourniquet use for up to two hours has no lasting negative impact on muscle tissue. However, our lab has recently shown that tourniquet use downregulates proteins regulating components of the cap-dependent translation initiation and elongation complex and upregulates proteins regulating catabolic pathways (MuRF1 and MAFbx) as well as stress activated protein kinases (SAPK/JNK). Tourniquet induced-anoxia reduces the rate of muscle cell metabolism. Studies have shown that the resultant ATP deficit leads to failure of the sodium potassium pump and subsequently to the building up of intracellular sodium and chloride ions. This change in ionic concentration causes water uptake and cell swelling. In this study, we used immunohistochemistry to analyze morpho- logical changes in muscle cells resulting from tourniquet-induced ischemia and subsequent reperfusion. We hypothesize that tourniquet use will result in muscle cell swelling. Preliminary data supports our hypothesis. Further research is needed to examine the role that cell swelling may play in post-surgical atrophy.

Impact of Estradiol and Progesterone on Muscle Sympathetic Nerve Activity in Young, Healthy Women

Presenters: Elisabeth Barrar, J.C. Miner, and J.A. Miner

Mentor: Christopher Minson

PM Poster Presentation

Poster 2

Alterations in muscular sympathetic nerve activity (MSNA) in healthy, young women (<40 years of age) have been seen during the early follicular phase of the menstrual cycle. Furthermore, oral contraceptives have also shown alterations in MSNA in active weeks versus placebo weeks. However, the independent effects of the hormones are unclear. PURPOSE: To investigate the independent effects of exogenous estradiol and progesterone on MSNA in young, healthy women. We hypothesized that administration of estradiol would increase MSNA burst incidence and burst frequency and that MSNA would not change with administration of progesterone in young, healthy women. METHODS: 18 young, healthy women subjects (BMI 18-25kg/m2) were studied under hormone suppression (with go- nadotropin-releasing hormone antagonist). Subjects were studied a second time following 2-3 days of either 0.2mg/day of transdermal estradiol supplementation (n=10) or 200mg/day of oral progesterone supplementation (n=8). On each study day, baseline MSNA in the peroneal nerve was recorded via microneurography for 10 minutes, and burst frequency and burst incidence were calculated. RESULTS: Estradiol decreased MSNA burst frequency from 8.39 to 5.40 bursts/min (p=0.02) and burst incidence from 14.51 to 9.18 bursts/100 heart beats (p=0.01). However, there were no significant differences following progesterone administration. CONCLUSIONS: Estradiol, but not progesterone, administration in young healthy women decreases resting baseline sympathetic activity.

Tramtrack69 Restricts Axon Growth through the Activin Signaling Pathway

Presenter: Alex Whitebirch

Mentor: Tory Herman

AM Poster Presentation

Poster 51

Connections between nerve cells are established by the outgrowth of long projections called “axons.” The motile end of a growing axon is the growth cone, a dynamic structure of actin filaments and microtubules. We are interested in how neurons downregulate the motility of their growth cones once the latter have reached their final targets. Studying this process may improve our under standing of how neurons control growth cone motility during regeneration after injury. In the Drosophila eye, R7 photoreceptor neurons are born in the retina of the fly and project their axons into the optic lobe. The Herman lab has found that the transcription factor Tramtrack69 (Ttk69) is required to prevent R7 axons from continuing to grow even after they reach their targets. Ttk69 is absent from R7s during axon outgrowth but present in R7s as their axons approach their targets. Early misexpression of Ttk69 causes premature termination of R7 axons. We conclude that Ttk69 is both necessary and sufficient to restrict axonal growth. We have found that Ttk69 does so by promoting signaling through the conserved TGF/Activin pathway. Because Ttk69 is known to be a transcriptional repressor, we hypothesize that Ttk69 represses an antagonist of the Activin pathway. Using RNA interference, I will disrupt expression of genes known to antagonize Activin signaling, including follistatin and cripto-like, in R7 cells lacking Ttk69. Suppression of the ttk69 mutant phenotype would indicate that the gene in question might be a target of Ttk69 repression.

MyMcKenzie: Creating a Portrait of the McKenzie River

Presenters: Cassidy Ventura, Mason Trinca and Rick Gurule

Mentor: Peg Boulay

AM Poster Presentation

Poster 49

Through photography and interpretation, as a group of Environmental Studies students in the Environmental Leadership Program, we created a portrait of the McKenzie River. As we have discovered the river and its people, we sought to reflect the river’s colors and motion, as well as the many relationships people have with this remarkable place. Our mission is to connect people to the McKenzie River, showing its beauty and how it influences people lives in numerous ways. We accomplished this by allowing people to follow our journey through our website, photo essays and photo exhibit to contemplate their own relationship to this majestic river. The themes represented in our poster and photographs include ‘Interaction’ showcasing the important roles this river plays in so many of our lives; ‘The Changing Colors’ devoted to all the colors of the McKenzie River that we experienced; and ‘Motion’ following the McKenzie River from the rapid falls of Sahalie to the steady waters of its confluence as it is in constant motion.

Analyzing Time of Chromosomal Rearrangment in Glioblastoma

Presenter: Anna Streitz

Mentor: Hui Zong

AM Poster Presentation

Poster 47

Glioblastoma is the most common and aggressive type of malignant brain tumor. Due to the tumor cell’s ability to disperse through- out the brain, their resistance to traditional chemotherapy and high rate of tumor relapse, current research is focusing on determining and designing therapies against the tumor cell-of-origin. In order to determine the cell of origin in these tumors, labeled mutant cells were generated through the use of mosaic analysis with double markers (MADM) allowing our lab to track the entire tumorigenic process in vivo and determine which cell types were giving rise to tumors. It was found that oligodendrocyte precursor cells (OPCs) were the primary cell type to show overexpansion and eventually give rise to a malignant tumor. It was hypothesized that by ablating the OPC cell population, using a genetic tool, one could prevent tumor formation or slow tumor growth. OPC specific thymidine kinase (TK) in conjunction with the drug Ganciclovir (GCV) was used in the hopes of causing OPC death. However, when end stage tumors were analyzed it was found that TK expression had been lost within the tumor cells, but not mutant OPCs outside of the tumor region. DNA analysis showed that the loss of the TK transgene had occurred on a genomic level, suggesting that a region of genomic DNA had been lost. The goal of this study is to characterize when the loss of TK occurs. Analysis of small tumors will reveal if TK loss is necessary for tumor growth or if it is lost as a function of tumor growth.

The Angry Cookie: Adults’ and Children’s Attribution of Human-like Facial and Emotional Characteristics to Inanimate Objects

Presenter: Mirjam Staeb

Mentor: Marjorie Taylor

AM Poster Presentation

Poster 45

Anthropomorphism is the tendency to describe inanimate objects with human-like characteristics. In this study we investigated individual differences in the perception of faces and emotional expressions in inanimate objects (e.g, a piece of toast with a pattern in the placement of raisins that made it look like a crying face). First, we investigated adults’ tendency to recognize faces in inanimate objects (N=32). The participants were shown pictures of human faces expressing different emotions, objects with features that could be interpreted as resembling human faces, and objects without such features and were asked to describe what they saw in each picture. We hypothesized that the degree to which adults characterized the pictures with human-like attributes would correlate with their scores on the Individual Differences in Anthropormorphism Questionnaire. The results of the adults’ study were used to develop a study with children in which they are shown a subset of the pictures and asked “What do you see in this picture?”. We were interested whether the ability to see faces in objects could be related to the children’s theory of mind, pretend play abilities and individual differences in other aspects of anthropomorphism. There were individual differences in the extent that adults described the pictures in anthropomorphic terms; the children’s data are currently being collected.