2014 Abstracts

Mahreen Bashir, University of Utah Humanities A complicated social paradox humanity faces is assessing the union between the seemingly contradictory ideologies of “sustainability” and “growth” into one viable system. Adapting a merger between concepts such as: the retention of cultural values and social systems, industry, urban sprawl, modernity, sanitation, progress and the environment. This objective of this research project centers around using understandings of post-colonial theory to find new connections in South Asian identity through South Asian literature written in English, and the literature’s relationship to ecology. Specifically, it applies the nascent subaltern lens of a historiography that examines South Asia as both a post-colonial subcontinent, and an emerging “superpower,” in the rhetoric of a global economy, to understand a relationship between Indian people and India as place. Questions asked are posed in regard to the affects of orientalism and a cultural infiltration of seeing endemic knowledge to be degenerate in relation to Western academia; Indian-American identity; and the weight of the term “subaltern” through works by South Asian writers. Furthermore, the project uses an ecocritical lens on these works to extract how identity discourse and post-colonialism have created understandings of Indian identity within English literature. The anticipated outcome of this research paper is to create a greater understanding of both emergent academic lenses, and their application in understanding Indian culture and identity as portrayed by works written by Indo-American writers. This research idea was born out of my passion for both ecology and post-colonial studies that I have honed through my studies as an environmental studies and gender studies double major. The main objective is to investigate the plurality of identity, and the ramifications that identity, has on the establishment of more sustainable behavior to counter the impending global crisis the planet is facing in terms of lack of environmental stewardship, and subsequent social justice.

Bradley Weaver, University of Utah Health High-grade gliomas, especially glioblastoma (GBMs, WHO Grade IV), are the most common primary brain tumors in humans. Despite recent advances in molecular targeted therapies for cancer, there has been little progress in treatment of GBMs. Median patient survival after diagnosis is dismal: approximately 12 months. Hypoxia is a key clinical marker of GBMs, which contain pockets of necrotic and hypoxic regions within the solid tumor mass. The transcription factors in the Hypoxia Inducible Factor (HIF) family are the master regulators of the cellular response to hypoxia. Their downstream targets include compounds that promote angiogenesis, increase glycolysis, and inhibit apoptosis. Recent research has identified glioma stem cells (GSCs) surviving within the hypoxic microenvironment, and has implicated HIF1α as a potential regulator of the GSC phenotype. GSCs are thought to promote therapeutic resistance and recurrence of GBMs after surgical resection. Clarifying the role of HIF1α in glioma stem cell dynamics is important for targeting both the tumor cells and their environment in new treatment. It is expected that GSC populations with more aggressive phenotypes will express higher levels of HIF1α and have higher proliferation rates under acute hypoxia. In this study, the HIF1α levels and proliferation dynamics of multiple, unique GSC cell lines are investigated. Cell lines used include two GSC lines isolated from primary patient tumors (NSC20/23) and a stem cell enriched high-grade glioma line. Preliminary results suggest that not all populations of GSCs respond the same way to hypoxic stress, and HIF1α may play a central role in stem cell dynamics, but not in the growth of non-stem tumor cells. Probing further into this relationship will increase our understanding of how brain tumors behave, and how to more effectively target them in patients. Further data and conclusions from this project will be available at the time of presentation.

Audrey Butler, Utah Valley University Life Sciences High-frequency (HF) ultrasound has been shown to be sensitive to a range of breast pathologies, and is being explored for the intra-operative assessment of lumpectomy margins. This sensitivity is believed to arise from microstructure-dependent interactions of ultrasound in the tissue. The objectives of this study were to develop breast tissue phantoms with microstructures that accurately mimic the histology of normal and malignant tissue, and to determine the effects of these microstructures on HF ultrasonic spectra (10-100 MHz). Phantoms were created from a mixture of water, gelatin, and soluble fiber. To simulate various breast tissue histologies, polyethylene beads, polyethylene fibers, and nylon fibers with a range of diameters were embedded into phantoms. Microstructures ranging from randomly dispersed beads to bead-fiber constructs resembling terminal ductal lobular units (TDLUs) were modeled and tested. Pitch-catch and pulse-echo measurements were acquired using 50-MHz transducers, a HF pulser-receiver, and a 1-GHz digital oscilloscope. Spectra were derived from the data and peak densities were determined from the spectra. Peak density, which is the number of peaks and valleys in a specified spectral range, has been shown to correlate with tissue complexity. Preliminary results from dispersed beads (58-925 µm diameter) of constant volume concentration (0.8%) indicated that the smaller beads produced higher peak densities than the larger beads with a consistent and statistically significant trend. These results substantially improve upon previous phantom studies and upon results from original breast cancer studies, demonstrating the strength of the HF ultrasound response to tissue microstructure. The higher peak densities can be attributed to either the higher number of scatterers for small beads or the size of scatterer in relation to the ultrasonic wavelength. These and other results from more advanced histologically accurate microstructures modeling TDLUs will be discussed.

Lance Deeter, University of Utah Life Sciences Continuous-flow left ventricular assist devices (LVADs) are used in advanced heart failure patients either to bridge them to transplantation or as a permanent-destination therapy. We determined whether chronic exposure to non-pulsatile blood flow and acute increases in coronary perfusion pressure associated with LVAD implantation would influence arterial function. Arteries from a transmural biopsy of the left-ventricle were obtained from ten male patients (54±4 years old) at the time of LVAD implant (n=17, 184±25 µm i.d.) and 239±51 days later upon LVAD explant (n=21, 281±22 µm i.d.). Lmax tension was determined and dose-response curves to potassium chloride (KCl, 10-100 mM) were performed using isometric tension techniques. Next, bradykinin (BK, 10-6 to 10-10 M) and sodium nitroprusside (SNP, 10-4 to 10-9 M) concentration-response curves were completed on vessels precontracted to ~65% of maximal tension development. Maximal BK-induced vasorelaxation was greater (p<0.05) at explant (85±5%) vs. implant (59±9%), while SNP evoked responses (~90%) were similar between time-points. These findings suggest coronary endothelial function is improved by LVAD implantation. Heart failure was precipitated by a myocardial infarction in six of the ten patients. These are referred to as “ischemic” patients whereas the remaining four are “non-ischemic” patients. We hypothesized that coronary vascular responses would be improved by LVAD implantation to a greater extent in ischemic vs. non-ischemic patients. In ischemic patients maximal BK-induced vasorelaxation was greater (p<0.05) in coronary arteries obtained at explant (87±6%, n=14, 305±30 μm i.d.) vs. implant (53±11%, n=12, 204±33 μm i.d.). In non-ischemic patients maximal BK-induced vasorelaxation was similar in arteries obtained at explant (79±9%, n=7, 232±21 μm) and implant (72±17%, n=5, 135±13 μm). SNP responses were similar (~90%) between groups at implant and explant. Collectively, our data suggest that LVAD implantation improves endothelium-dependent vasorelaxation in ischemic but not in non-ischemic patients.

Shwan Javdan, University of Utah Life Sciences Each year in the United States, over 22,000 new cases of ovarian carcinoma are diagnosed and 14,000 women die from its progressive cancer stages. Anthracyclines, a class of common chemotherapy drugs, have long been the primary treatment for this and many other cancers, but they often leave patients with cardiotoxicity, hepatotoxicity, and other adverse effects. Polymer-drug conjugates using poly[N-(2-hydroxypropyl)methacrylamide] (poly-HPMA) are nanosized, water-soluble constructs that accumulate passively in solid tumors by the enhanced permeability and retention effect as well as actively by cell surface targeting methods. As such, they have exhibited reduced toxicity in the body. The goal of this study was to develop a novel, targeted HPMA copolymer-drug conjugate for the treatment of ovarian carcinoma. To accomplish this, an antibody fragment called Fab’, targeted to ovarian carcinoma cell surface antigen OA3, was bound to an HPMA copolymer-gemcitabine conjugate. Gemcitabine is a nucleoside analog used in chemotherapy that has demonstrated considerable effectiveness in recent years. The copolymer-gemcitabine conjugate was successfully developed following the synthesis of all the requisite components, including Fab’, diblock chain-transfer agent (di-CTA), N-(2-(2-pyridyldithio)ethyl)methacrylamide (PDTEMA), and polymerizable backbone-degradable gemcitabine derivative. Syntheses of di-CTA and PDTEMA were optimized and then characterized by high-performance liquid chromatography, H-NMR, and mass spectrometry. Monomers were combined by reversible addition-fragmentation chain-transfer polymerization, and then the Fab’ fragment was bound to the polymer backbone via a disulfide exchange reaction with PDTEMA. The targeted copolymer-drug conjugate was then verified by fast-protein liquid chromatography as well as ultraviolet-visible spectroscopy. A number of in vitro tests have demonstrated the properties of an efficient drug delivery system. Flow cytometry displayed active accumulation of the copolymer-gemcitabine conjugate to OVCAR3 cell surfaces. Furthermore, IC50 measurement found promising drug efficacy comparable to modern anthracyclines. Future work will involve in vivo evaluation of the conjugate’s therapeutic efficacy in nude mice bearing OVCAR3-xenografts.

Ryan Watkins, Univeristy of Utah Life Sciences The lymphatic system is responsible for controlling systemic fluid buildup. Lymphangiogenesis is a dynamic process involving sprouting and maintaining new lymphatic vasculature. Vascular endothelial growth factor C (VEGF-C) is known as a key growth factor through VEGF receptor 2 and 3 (VEGFR2 and VEGFR3). Interestingly, the cornea expresses VEGF-C but is alymphatic. We found that the soluble isoform of VEGFR3, which lacks tyrosine kinase domains, is responsible for the alymphatic nature of the cornea by sequestering endogenous VEGF-C. Although soluble VEGFR3 or soluble VEGFR2 can be useful for inhibition of VEGF-C derived lymphangiogenesis, they also bind VEGF-A. Inhibition of VEGF-A suppresses blood vessel formation, damaging tissue and creating additional side effects. The development of a new anti-lymphangiogenic drug, that only blocks VEGF-C, has many implications: preventing tumor metastasis and reducing rejection rates of tissue and organ transplants. VEGF-C mainly binds to VEGFR3 domain 2 and VEGFR2 domain 3. To develop an anti-lymphangiogenic drug that specifically binds VEGF-C the binding domains were inserted into a vector that produces a recombinant protein (VEGF-C trap) that sequesters VEGF-C, suppressing lymphangiogenesis. Mice in a cornea transplantation model were treated with VEGF-C trap. After 8 weeks, 60% of the treated cornea survived (no rejection) compared to 10% in the empty vector control group. A 60% transplant survival rate is one of the highest rates compared to other single treatment methods. Blood and lymph vessel area was calculated and showed a decrease in lymph vasculature but not blood vessel. Suggesting only VEGF-C activity was affected. In a tumor metastasis model, nude mice will be injected subcutaneously with cultured MCF-7 cells which have been transfected with VEGF-C trap or an empty vector. We expect to see a decrease of lymphatic vasculature in the mice injected with MCF-7 cells containing the VEGF-C trap and ultimately less metastasis.

Ashley Calder, Utah Valley University Life Sciences An estimated 50-80% of dementia patients suffer from Alzheimer’s disease (AD). Currently there is no test to diagnose AD except post mortem. Recent papers indicate that AD affects the cytoskeleton and cellular structure through mutations that alter structural proteins, and that dysfunction of the cytoskeleton may play a pivotal role in AD and other neurodegenerative diseases. In particular, specific genetic components of AD affect microtubule and actin filaments that control endocytosis, exocytosis, the shape and size of the neuron, vesicular transport along neurites (dendrites and axons), and fibril formation. The goal of our research is to determine if breast cancer molecular subtypes can be used as a model for AD. Breast cancer is comprised of five molecular subtypes that contain different molecular structures depending on mutations specific to each subtype and the proteins being synthesized. These mutations and their expressed proteins change the characteristics of the cytoskeleton and resulting properties of the cell such as size, shape and stiffness. Both computer simulation and experiment have demonstrated that high-frequency ultrasound in the 10-100 MHz range is sensitive to these properties. For this study, ultrasonic tests were conducted on monolayer cell cultures of breast cancer cell lines of different subtypes. Ultrasonic waveforms were analyzed by transforming them into their corresponding spectra. The positions, widths, and shapes of the spectral peaks were compared and correlated to model results using a pattern recognition algorithm. Preliminary results indicate that cell stiffness and size can be determined from the measurements. Further analyses of these and additional data will determine if ultrasound is sufficiently sensitive to differentiate between the molecular subtypes of breast cancer. Results from these analyses, future studies with neuron cell cultures, and application of the results to the development of a minimally invasive, in vivo method for accurately diagnosing AD will be discussed.

Ashley Nelson, Brigham Young University Life Sciences The motivational effects of opiates and ethanol switch from a dopamine (DA)-independent to a DA-dependent pathway when the animal is in a drug-dependent state. A corresponding change occurs in ventral tegmental area (VTA) GABA(A) receptors in opiate-dependent animals, which switch from a GABA-induced hyperpolarization of VTA GABA neurons to a GABA-induced depolarization. The aim of this study was to evaluate VTA GABA neuron excitability, GABA synaptic transmission to VTA GABA neurons and GABA-mediated DA release in the nucleus accumbens (NAc) under ethanol-naïve and dependent conditions. To accomplish these studies, we used standard whole-cell and attached-cell mode electrophysiological techniques to evaluate acute and chronic ethanol effects on VTA GABA neurons in GAD GFP mice, which enabled the visual identification of GABA neurons in slice preparation. In naïve animals, superfusion of ethanol (IC50 = 30 mM) and GABA(A) receptor agonist muscimol (IC50 = 100 nM) decreased VTA GABA neuron firing rate in a dose-dependent manner. Compared to saline-injected controls, in animals made dependent on ethanol by twice daily injections of 2.0 g/kg ethanol, neither ethanol nor muscimol significantly affected VTA GABA neuron firing rate on average. We and others have found that ethanol decreases DA release at terminals, as measured by fast scan cyclic voltammetry. We have recently reported that ethanol inhibition of DA release at terminals in the NAc of ethanol-naïve animals is mediated by GABA, possibly from VTA GABA neurons that project to the NAc. We evaluated the effects of ethanol on DA release in the same ethanol-dependent animals. Compared to controls, superfusion of ethanol did not significantly affect DA release. Together, these findings suggest that VTA GABA neurons undergo a switch in GABA(A) receptor function with chronic ethanol, which results in a corresponding switch in DA release, perhaps resulting from adaptations in VTA GABA neuron input to the NAc.

Brett Gardiner, Brigham Young University Life Sciences Normal human anatomy used in the classroom is not reflective of variations confronted in pathology subjects. Current commercialized models are not products of real data, rather representations of it. While learning complicated medical anatomy, students take an enormous stride from the anatomy lab to situational surgical settings. 3D models can bridge this gap in medical education without patient risk, particularly for the brain where surface regions have strong associations to specific physiological activity. Subject specific models are especially advantageous for comprehending real surface morphology of neurologic diseases. Using rapid prototype technology, we have developed an accessible process to produce physical 3D models from specific MRI data of stroke and Alzheimer’s subjects. The neuroanatomical abnormalities modeled from real data by our 3D printouts will educate students on the anatomical variations encountered in an authentic clinical scenario of neuropathology. Our project consists of three phases: (1) image acquisition, (2) post-processing imaging data with segmentation, and (3) 3D printing. By delineating cortical regions we are providing a unique multidimensional facet of clinically accurate data not before available to the classroom. This powerful and versatile technique can allow students and professionals to visualize the inherently complicated structures as seen in clinical neuropathology. From students in the classroom, lawyers in the courtroom or preoperative surgical explanations, these customizable models will resemble real anatomical information. Through rapid prototyping of specific subject data, unique variations in pathology can be reviewed outside of the clinical setting. Beyond its potential use by teachers, lawyers and doctors can benefit from a 3D production to enhance their explanations of anatomical variations from specific pathological subject data.

Dusting Day, Brigham Young University Life Science Atherosclerotic vascular disease is the leading cause of morbidity and death in the United States. Approximately 1.4 million surgical procedures are required every year for treatment of vascular disease and its subsequent issues. While saphenous vein and internal mammary artery grafts are most commonly chosen by physicians, many patients who are in need of arterial grafts have vessels that are not ideal for grafting because of damage to the vessels or disease. This introduces the necessity for synthetic blood vessel grafts that function precisely as natural vessels in vivo. Our blood vessel research team has entered the tissue engineering field in its most exciting effort: the scalable rendering of cell-seeded vascular constructs with rapid prototyping machines or 3D printers. We have built and are modifying a 3D printer to deposit living endothelial and smooth muscle cells into vascular structures. Using agar, alginate, or collagen gels as placement media, cells can be arranged in shapes resembling multilayered artery tubules and proliferate to form functional arteries. The endothelial layer and smooth muscle layer of cells interact to secrete a natural extracellular matrix (ECM) between them. We have successfully cultured endothelial cells and are perfecting our technique of harvesting aortic smooth muscle cells for culture. These cells will be encapsulated in a gel we have optimized for cell adhesion and proliferation and will then be printed with our rapid prototyping machine into the shape of a blood vessel. After proper cell growth and secretion of the ECM we will subject our synthetic graft to tensile strength testing, thrombosis tests, and eventually implantation into an animal for observation of any immunogenic effects. Our project’s success would bring an array of new treatment options through biomedical engineering that would save many lives of those who suffer from cardiovascular disease.