2014 Abstracts

Samantha Smiley, Brigham Young University Mathematical Sciences Dementia is a clinical syndrome characterized by an overall loss of cognitive ability. There are multiple forms of dementia with various causes and various impacts on the suffering individuals. Accurate diagnosis is essential to effective intervention and treatment. Currently, clinicians lack a biological marker that definitively distinguishes the different forms of dementia. Hence, they rely on physical exams, neuropsychological tests, and patient report to provide a diagnosis. Recent advances in brain imaging make it possible to obtain detailed maps of brain activity, which in turn may offer insight into many conditions such as dementia. Developing a predictive model from patient data, including brain scans, would greatly enhance the ability of clinicians to provide accurate diagnosis, and hence appropriate treatment, to their patients. Doing so, however, is not trivial as patient data is heterogeneously and non-uniformly distributed across sites, where some sites have far more data than others and calibration varies among scanners used. We report on the development of novel predictive models based on distributed learning for the effective diagnosis of dementia.

Steffan Larsen, Brigham Young University Mathematical Sciences The popularity of metamaterials has exploded with in the last decade. Metamaterials are materials that exhibit interesting properties not found in nature; one of the most widely known features being a negative refractive index. Metamaterials are composites different types of materials that give them their interesting properties. In addition to being composed of several element types, metamaterials also contain certain inclusions that influence their electromagnetic properties. Among these are space filling curves. Space filling curves are curves that are entirely contained within a specific area and yet can become infinitely long. In my research I investigated the properties of space filling curves and their application/benefit to the research surrounding metamaterials, specifically metamaterial antennas.

Brennon Bauer, Southern Utah University Mathematical Sciences We study the Lotka-Volterra competition model. This model can be applied to Math Biology. We propose a Semi-Implicit numerical scheme, which guarantees that the populations are always positive. Also we prove that the numerical scheme is uniquely solvable, and is unconditionally stable.

Ariel Herbert-Voss, University of Utah Mathematical Sciences A typical problem in numerical analysis is finding a smooth interpolation of a given data set such that information at extended positions can be evaluated. When extended to higher dimensions, there are few such algorithms available for practical use. Drawing from techniques used in geometric modeling we developed a practical algorithm with improved complexity by implementing the techniques in a query model as part of a MATLAB software package. From initial input data the algorithm builds a d-dimensional cell complex using Delaunay triangulation. Each cell has an associated interpolation function that satisfies Lipschitz continuity for each new point. During query time the user specifies a query point and the algorithm returns the interpolated function value. To reduce complexity related to point location within the cell complex, we implemented a binary tree search based on hyperplane decision criteria. Efficiency analysis completed using benchmark data sets indicated that the decision tree algorithm improved the efficiency from O(N) to O(N log N). This algorithm is the first of its kind that can be used on actual data sets and is the first implemented as a MATLAB package.

Nirdosh Chapagain, Brigham Young University Mathematical Sciences Rainbow is an optical phenomenon created by reflection and refraction of light at the boundaries of water droplets. Descartes was the first to provide a geometric explanation for the optics of the rainbow. We use Descartes’ method to examine if rainbow effect is possible with metamaterial droplets. Metamaterials are artificial materials whose permittivity and permeability can be simultaneously negative hence, giving them negative index of refraction for certain frequencies. The recent extraordinary level of output in the field of metamaterials has resulted in examinations of applications of these substances to a variety of fields, including the arrow of time and cloaking. Many applications of metamaterials can create physical effects that were previously assumed impossible. In this study we have considered that our hypothetical droplet has negative refractive index for visible band of the electromagnetic spectrum. We also examine the effect of using composite metamaterial droplets.

Ammon Washburn, Brigham Young University Mathematical Sciences In many problems with seepage flow, there are non-linear problems that don’t have an easy analytical solution. There is already good research on what can be done in certain situations with these problems. I will present on numerical methods that have been proven to solve certain conditions and then present other solutions for similar problems where the numerical method isn’t so readily available in past research. I will implement the algorithms and compare results.

Kyle Hansen, University of Utah Life Sciences Our brain processes physical stimuli from the world around us to shape how we perceive our environment. In the olfactory system, this processing begins with olfactory sensory neurons that relay information about distinct odorants to a region of the brain called the olfactory bulb. Olfactory sensory neurons express the same odorant receptors converge onto structures within the olfactory bulb called glomeruli. Here, we map lateral interactions between glomeruli to better understand how olfactory information from the environment is processed within the olfactory bulb. Using GCaMP6, a fluorescent calcium indicator, in awake mice we can observe optogenetically-evoked patterns of lateral connectivity between glomeruli in the olfactory bulb. The findings from this study will help clarify potential interglomerular connection schemes and provide understanding of how local circuitry in the olfactory bulb transforms the representations of sensory information before it is relayed to higher brain areas.

Brady Evans, Brigham Young University Life Sciences Nutrient-sensing kinases, such as AMPK and mTOR, play a key role in regulating cellular metabolism. They recognize nutrient levels within the cell and distribute nutrients accordingly. The failure to coordinate metabolic processes can lead to diseases such as diabetes, obesity and cancer. PAS kinase is another member of the nutrient-sensing kinase group that regulates glucose distribution in the cell. Despite its clear importance, little is known about the mechanisms regarding PAS kinase activation and its function. Studies have shown that mice without the PAS kinase gene are resistant to weight gain and maintain insulin sensitivity when placed on a high fat diet. Weight gain and insulin resistance are associated with increased rates of diabetes, cancer and other metabolic diseases. AMPK is currently the key target for the treatment of diabetes and has been found to be a cancer target as well. The yeast homologue, Snf1, is necessary for activation of yeast PAS kinase. Further studies have shown that PAS kinase is activated under the same respiratory conditions as Snf1. The aims of this project is to determine if Snf1 directly phosphorylates PAS kinase and to determine the effects of this phosphorylation. We have found that PAS kinase is activated quickly when cells are placed under Snf1-activating conditions. In addition, Snf1 is necessary and sufficient for this activation. Snf1 also copurifies with PAS kinase suggesting this activation is direct. PAS kinase purified from wild type verses Snf1-deficient cells shows phosphorylation on two key residues, S1020 and S1035. In addition, Snf1 directly phosphorylates PAS kinase in vitro. Together these findings suggest that Snf1 directly phosphorylates PAS kinase in order to regulate cellular glucose homeostasis

Sharisa Nay, Brigham Young University Life Sciences Gene therapy is a growing field of science with the potential to improve thousands of lives. With an eye toward improving the effectiveness and longevity of gene therapies, my project examines the preferential binding tendencies of the histone protein variants Htz1 and Htas1. Htz1 is the Ceanorhabditis elegans homolog of H2AZ, an important variant of the H2A histone. This protein has been shown as necessary for survival and as playing a role in the prevention of ectopic heterochromatin spread. Htas1 is another variant of H2A that plays a role in the increased transcription of sperm-producing genes. The preferred positioning of these variants on naked DNA is not yet known. Through a DNA extraction, nucleosome reconstitution, and DNA digest and sequencing, we will take these variants and examine where they are prone to localize within the N2 Bristol strain of c. elegans. This will allow us to include DNA sequences on our gene insertions possessing a high binding-affinity for these transcription-promoting histones. Thus, if we can identify the locations at which these variants will localize within DNA, we will be able to insert these preferred constructs into the genes used for gene therapy and thereby increase the effectiveness of gene therapies.

Joe Passman, University of Utah Life Sciences Neurodegenerative disorders and amyloidosis are thought to be a consequence of the misfolding of intrinsically disordered proteins (IDPs). In non-pathogenic states, IDPs are thought to manipulate their configurational ensembles (CEs) – through partially folding and/or forming secondary structure – to create binding sites for the multiple interaction partners necessary for cell-signaling, recognition, and regulation. An obstacle to accurate in vivo understanding of non-pathogenic mechanisms is that little is known about the impact of the crowded cellular environment on the global (i.e. partial folding) and local structural characteristics (i.e. secondary structure) of IDPs. It is difficult to understand why an IDP may misfold if little atomistic structural understanding exists regarding IDP functional mechanisms in non-adherent physiological states.

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.

Julia Hull, Weber State University Life Sciences Endophytes are fungi that live within aerial portions of plants for most or all of their life cycle without causing visible signs of disease. Gall forming aphids, Pemphigus betae, are highly competitive over gall site selection (Moran 1993), forming galls on the leaves of narrowleaf cottonwood and their hybrids. The favored gall location overlaps with areas of highest endophyte probability. I hypothesized that a negative correlation would exist between endophyte infection and aphid galling on leaves of backcross hybrid cottonwood trees.

Brianne Palmer, Utah State University Life Sciences Inversions have plagued the valleys in Utah resulting in built up pollution carpeting the cities and spreading into surrounding ecosystems. The ecological impact of these inversions is unknown. Inversion-based pollution events deposit nutrients and pollutants in the ecosystems. The purpose of this study is to determine if lichens, due to their unique physiology, preserve a record of inversion-based nitrogen deposition in order to assess the ecological impact of the inversions. In June and July of 2013 we collected 111 samples of lichens from sites exposed to the inversions, along Red Butte Creek and on an elevation gradient on Grandeur Peak in Salt Lake City. The collection focused on two species of lichens (Xanthomendoza montana and Xanthomendoza fallax) because they are easily identifiable and live in all the sampling sites. The samples were ground, run through a stable-isotope mass spectrometer and analyzed for the %N and δ15N. If lichens hold a record of inversion-based depositions there should be more nitrogen in lichens from the sampling sites closer to the pollution source (Salt Lake City). Once the data was complied, the resulting graphs showed no correlation between %N and distance from Salt Lake City between δ15N and the pollutant source. However, the isotopic variability within the samples was greater than expected and requires further research.

Preston Manwill, Southern Utah University Life Sciences Plants produce compounds, secondary metabolites, which can be harnessed for medicinal uses. Caryophyllene, a secondary metabolite produced by a variety of higher plants, has shown promise as an analgesic and anti-inflammatory. Caryophyllene synthase is the final enzyme in the biosynthetic pathway that produces caryophyllene. The gene and enzyme responsible for caryophyllene production have been observed in crop plants and model organisms, but few studies have investigated caryophyllene production in indigenous plants. We investigated the production of caryophyllene in Ericameria linearifolia (Narrowleaf goldenbush) because it is a shrub native to southwest North America. The first portion of this research examined sequence similarities between caryophyllene synthase gene orthologs in E. linearifolia and other plant genera. Genomic DNA was isolated from E. linearifolia leaves collected from plants growing in southern Utah. Literature reviews and database inquiries have provided DNA sequences for similar synthases, from which primers will be designed to copy and sequence the E. linearifolia caryophyllene synthase gene, confirming the orthologs presence. Following confirmation of the gene, mRNA will be extracted from leaf material and oligo(dT) primers used to synthesize cDNA. Subsequent cDNA amplification and cloning of products into a vector will allow for transformation into a protein-producing bacterium. These final steps make the downstream procedures of protein production, structure determination, and functional characterization of the protein possible. Comparison with enzymes that produce similar organic compounds may result as well, and would provide insight that could improve the biosynthesis of medicinal compounds.

Preston Manwill, Sourthern Utah University Life Sciences Plants produce myriad secondary metabolites (essential oil) that play a role in ecological interactions. Species evolve unique mixtures of organic compounds due to strong selective pressures that act on metabolic pathways. Few studies have investigated the antimicrobial properties of secondary metabolites that evolved against soil microbes associated with native plants. The essential oil of Mojave goldenbush (Ericameria linearifolia), a shrub native to the Intermountain West, was characterized and its bacteriostatic abilities against root associated and non-root associated bacteria morphs were examined in this study. We hypothesized E. linearifolia oil would act as a greater growth inhibitor against native soil bacteria with which it has evolved than against bacteria from non-associated soils. Secondary metabolites were extracted using steam distillation and analyzed with gas chromatography mass spectroscopy. A Kirby-Bauer assay tested presence, size and retention of inhibition zones (IZ) produced against soil bacteria. The essential oil of E. linearifolia contained twenty secondary metabolites, two of which, limonene and sabinene, constituted greater than fifty percent of the oil. Presence and retention of IZ produced by E. linearifolia metabolites varied significantly by community association and bacteria morph. The hypothesis was supported by IZ that were largest against bacteria cultures isolated from soil that surrounded Mojave goldenbush roots and least effective against cultures isolated from non-root associated soil. Our findings suggest that secondary metabolites of E. linearifolia have evolved to specifically prevent negative interactions with bacteria most associated with the plant.

Cameron Sargent, Brigham Young University Life Sciences Although viruses present a potential solution for treating and studying many harmful diseases, they have yet to be utilized successfully, largely due to an overall lack of understanding of the interactions between viruses and their hosts. This study, however, demonstrates the efficacious usage of comparative genomics in further elucidating viral reproduction mechanisms, a step in overcoming this hurdle. Following the sequencing and annotation of genomes of the B4 subcluster of mycobacteriophage, a previously unstudied selection of viruses, comparative genomics analysis identified regions of proteins from these viruses that are highly conserved, or highly similar. One of these B4 phage proteins was then compared on the basis of its predicted folded structure and its amino acid composition to a protein with the same function from another phage, whose structure and DNA binding mechanism was determined via NMR spectrometry. Gene sequence alignments identified the region of highest conservation in the B4 phage. Protein folding then revealed that this region created a structure that was analogous to the functional region of the protein studied elsewhere, indicating that it too recognizes, binds to, and modifies DNA in the same manner. Furthermore, another DNA-binding motif with high conservation among B4 phage was observed in both the folded B4 proteins and the protein analyzed via NMR spectrometry. This comparison procedure not only further elucidated the function of an important gene in B4 phage but also displayed that comparative genomics, a resource-effective and computer-based approach, can successfully identify the critical functional regions of a protein. This study therefore provides a novel procedure for further understanding the mechanisms of virus-host interactions, which in turn facilitates the successful application of viruses in treating and studying diseases.

Eliza Warren, Brigham Young University Life Sciences We have previously demonstrated that ethanol inhibition of medium spiny neurons (MSNs) in the nucleus accumbens (NAc), and γ-aminobutyric acid (GABA) neurons in other ethanol-sensitive brain areas, is mediated by GABA(B) receptors. The aim of this study was to evaluate the involvement of GABA and glutamate (GLU), and in particular GABA(A), GABA(B) and NMDA receptors, in mediating ethanol inhibition of dopamine (DA) release in the NAc. Using fast scan cyclic voltammetry (FSCV), we evaluated the effects of ethanol on DA release in the NAc core of C57/BL6 and CD-1 mice. In the slice preparation, local stimulation evoked robust, frequency-dependent DA release in the NAc, with maximal release at 20 Hz. Ethanol decreased DA release with an IC50 of 60 mM in C57Bl6 mice. In anesthetized C57BL6 mice, ethanol decreased DA release with an IC50 of 2.0 g/kg. Superfusion of the GABA(B) receptor antagonist CGP55845 enhanced DA release 85%, while neither the GABA(A) receptor antagonist bicuculline, the GABA(A) receptor agonist muscimol, the GABA(B) receptor agonist baclofen, nor the NMDA GLU antagonist APV significantly affected DA release. CGP55845 blocked ethanol inhibition of DA release, while neither bicuculline nor APV altered ethanol’s effects. GABA inhibited DA release at 0.5-10 uM but not at 0.1-1 mM. Compared to ethanol effects on DA release in C57BL6 mice, CD-1 GAD GFP knock-in mice, which only express GAD at 50% levels, were significantly less sensitive to ethanol. As DA release was sensitive to low concentrations of GABA, CGP55845 may act as a GABA(A) rho receptor antagonist, and neither bicuculline nor baclofen had any effect on DA release, ethanol may be acting on extrasynaptic GABA(A) rho receptors on DA terminals to inhibit DA release in the NAc.

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.

Kevin Nay, Southern Utah University Life Sciences Leech taxonomy has traditionally been based on morphological characters, but with new developments in DNA technology many taxonomists are starting to use genetic information in descriptions of new species. Leeches in southern Utah are poorly inventoried with respect to many other aquatic animals. There have been few morphological inventories of leeches and even fewer descriptions of the genetic diversity within leeches. Landscape genetics is a powerful tool used to understand geographic patterns of genetic diversity. Southern Utah has many naturally isolated bodies of water due to the climate and the dramatic changes in elevation in this part of the country. The landscape genetic study of leeches in southern Utah will provide us with a better understanding of genetic differentiation within southern Utah leeches. The mitochondrial DNA (CO I region) will be used to estimate genetic diversity and examine the relationships among individuals in two populations of leeches. I hypothesize that leeches in southern Utah will have greater genetic diversity then historically recognized from morphological studies suggesting a new species of leech. The study will lead to better understanding of the taxonomy and identification of southern Utah leeches.

Preston Manwill, Southern Utah University Life Sciences Members of Anthoxanthum (sweetgrass) have a history of ceremonial and medicinal use. Coumarin, a secondary metabolite produced by the grass, is an anticoagulant and antimicrobial agent. Antimicrobial properties of commercially available European A. odoratum metabolites have been nominally investigated, but no North American species have been studied. Additionally, European sweetgrass is purported to be available in both diploid and polyploid strains. Our research objectives were to: 1) determine if ploidy level strains do exist, and 2) investigate secondary metabolite production and evolution in commercial strains and A. hirtum, a Great Basin native. Using epidermal casts and fuschin staining, differences in guard cells and nuclei were surveyed. Secondary metabolites from the A. odoratum strains and A. hirtum were obtained through steam distillation and a vacufugation protocol that concentrated hydrosols. GC/MS analyses characterized and quantified secondary metabolites. The secondary metabolites coumarin, dihydrobenzofuron, and dihydroactinidiolide were identified, with the first and latter greatest in A. hirtum. Significant guard cell differences between strains, as well as species, were observed. Two ploidy strains of A. odoratum were suggested. A Kirby-Bauer assay tested presence, size and retention of inhibition zones (IZ) produced against soil bacteria. Gram-staining initially characterized bacterial morphs. Secondary metabolites from the diploid strain were most effective against all bacterial morphs, but polyploid metabolites also generated and retained IZ against diploid root associated and non-root associated morphs. The native sweetgrass produced IZ only against root associated bacteria with which it had evolved. Future work will include similar studies of other North American Anthoxanthum species.

Justen Despain, Brigham Young University Life Sciences Mycobacterium ulcerans is an acid fast intracellular bacteria that is the causative agent of Buruli Ulcer, a disease endemic in tropical regions of Africa. The disease starts as a nodule that progresses into a necrotizing skin lesion. Treatment ranges from antibiotic therapy to surgical removal of surrounding skin to stop necrotization of the skin. Owing to the intracellular nature of M. ulcerans, antibiotic therapy can be an ineffective treatment option. It has been previously shown that mycobacteriophage can reduce extracellular bacterial load in mice infected with M. ulcerans. In this study, we propose a method of killing intracellular M. ulcerans by mycobacteriophage using avirulent Mycobacterium smegmaits as a vector.

Bryan D Merrill, Brigham Young University Life Sciences The spore-forming bacteria Paenibacillus larvae causes American Foulbrood (AFB), a highly contagious disease that is lethal in honey bee larvae. P. larvae is the most serious pathogen affecting honey bees. Its increasing antibiotic resistance has led to more research in characterizing bacteriophages which infect and destroy P. larvae. Of the 13 P. larvae phages that have been described in publications, six have been fully sequenced and are currently available for genomic analysis. To understand how P. larvae phages are related to each other and to other phages, the computer program Phamerator was used to analyze more than 100 phage genomes and group phage genes into “phams” based on similarity. Through analysis of grouped phage genes (structural proteins, terminases, recombinases, etc.) we can better understand in vivo replication strategies and evolutionary history of these P. larvae phages.

Taylor Woodward, Brigham Young University Life Sciences The prevailing view is that enhancement of dopamine (DA) transmission in the mesocorticolimbic system, consisting of DA neurons in the ventral tegmental area (VTA) that innervate the nucleus accumbens (NAc), underlies the rewarding properties of alcohol and nicotine (NIC). Dopamine neurotransmission is regulated by inhibitory VTA GABA neurons. We have shown previously that VTA GABA neurons are excited by low-dose ethanol, but inhibited by moderate to high-dose ethanol. The aim of this study was to evaluate the role of []6 nicotinic cholinergic receptors (nAChRs) in ethanol effects on VTA GABA neurons as well as DA release in the NAc. In electrophysiology studies, superfusion of ethanol enhanced the frequency, but not amplitude, of mIPSCs recorded in acutely dissociated VTA GABA neurons from GAD GFP mice. The []6 nAChR antagonist []-conotoxin P1A did not affect mIPSCs, but prevented the ethanol (30 mM)-induced increase in mIPSC frequency. While microdialysis studies show that ethanol enhances DA release in the NAc, we and others have found that ethanol decreases DA release at terminals using fast scan cyclic voltammetry (FSCV). We have reported that ethanol inhibition of DA release at terminals in the NAc of ethanol-naïve animals is mediated by GABA. Using FSCV in the slice preparation, ethanol inhibited DA release in the NAc. Superfusion of the []6 nAChR antagonist []-conotoxin MII did not affect DA release, but prevented ethanol inhibition of DA release. Taken together, these findings suggest that ethanol enhancement of GABA inhibition of VTA GABA neurons is mediated by []6 nAChRs located on GABA terminals to other VTA neurons, affecting DA release in the NAc. Results from this study could provide a pharmacologic rationale for considering drugs that act selectively on nAChRs as therapeutic agents for the treatment of alcohol dependence and alcohol and NIC co-dependence.

Corey Wolf, Westminster College Life Sciences The yeast species Saccharomyces cerevisiae is used in numerous industries including brewing, baking, and winemaking. In recent years an increased demand for low ethanol beers has pushed breweries to develop a beer that is both rich in flavor and low in alcohol content. The current strategies employed to decrease the ethanol concentration in beer are costly, time intensive, and result in less flavorful beers. In this study, a method for decreasing alcohol content in the brewing process through the use of metabolic inhibitors of Alcohol Dehydrogenase is tested. Alcohol Dehydrogenase is the enzyme responsible for the conversion of acetaldehyde, an intermediate in the metabolic pathway of yeast, into ethanol. Two competitive inhibitors of Alcohol Dehydrogenase, Pyrazole and Fomepizole, were applied to small scale fermentations in varying concentrations in an attempt to decrease the overall ethanol yield of the beer. The application of either inhibitor resulted in an initial decreased rate of fermentation overall, measured as a change of sugar and ethanol concentration. In the later stages of fermentation, the rate of ethanol production returned to normal, suggesting the inhibitors were either catalyzed or removed by the cell. While this method for manipulating the products of fermentation did not yield the desired effects, this study did highlight the importance of the fermentation pathway for maintaing healthy Saccharomyces cerevisiae cultures. This research may be helpful in understanding the complete metabolic pathway of brewer’s yeast, with further application to organisms with conserved pathways.

Camrin Rivera, Westminster College Life Sciences The Great Salt Lake (GSL) of Utah is home to organisms that are able to survive and reproduce in waters that can have a salt concentration of over 30%. Oil Jetty is located on the saltier north arm of the GSL and is the location of a natural hydrocarbon seep that flows into the lake. Previous work showed that organisms capable of degrading hydrocarbons can be cultured from this area (Ward & Brcok, 1978). It has also been shown that the salt concentration has an inverse relationship with these organisms’ ability to degrade hydrocarbons (Ward & Brock, 1978). This previous study gives insight of the hydrocarbon degrading capabilities of microorganisms in the GSL; however, the identification and characterization of individual hydrocarbon-degrading microorganisms has yet to be completed. The purpose of this study is to identify GSL microorganisms capable of degrading hydrocarbons under high salinities by sequencing of the 16s rRNA gene. Future studies will include the characterization of these microorganisms in order to find isolates whose hydrocarbon degrading abilities could be utilized for bioremediation and biotechnologies.

Hailey Shepherd, Dixie State University Life Sciences Previous studies of canyon tree frogs (Hyla arenicolor) in Zion National Park have shown that some populations test positive for a dangerous fungus in the Chytridiomycosis family. This fungus has been linked to large population losses worldwide in many keystone amphibian species, but appears to have no effect on populations of H. arenicolor. Since Chytrid fungal growth is inhibited at high temperatures, we hypothesized the frogs are able to rid themselves of the fungus because they bask in the sun. During the summer of 2013 we swabbed frogs in multiple slot canyons to test for the presence of the fungus. We also recorded skin temperatures of the frogs we swabbed. Skin temperatures were as high as 38 C°, which is above the previously established lethal threshold of 28 C° for Chytridiomycosis. Our data support the idea that these frogs may be able to rid themselves of infection by allowing skin temperatures to raise enough to become intolerable for this fungus. This is the first known evidence of wild amphibian populations showing a behavior that may clear the infection. If further research supports these findings, it could lead to more effective allocation of limited conservation resources.

Merrill Christensen, Brigham Young University Life Sciences Selenium (Se) has established chemopreventive efficacy against prostate cancer, the second leading cause of cancer death among men in the US. Currently, most studies only employ one single chemical form of Se, even though different forms of Se act through varied mechanisms to achieve their anticancer effects. In this study, we propose that systematically combining multiple forms of Se will produce an optimal combination of Se compounds to inhibit in vitro prostate cancer cell growth. As proof of principle, we (1) synthesized Se nanoparticles (nano Se), (2) determined the IC50s of methylseleninic acid (MSA), sodium selenite, and nano Se in PC-3 cells, (3) utilized mixture designs and response surface methodology to direct our combination experiments with these three compounds, (4) tested the fifteen combinations determined in the previous step, and (5) constructed a polynomial model to derive the optimum combination of MSA, sodium selenite, and nano Se to inhibit PC-3 cell growth. Our results showed that combining different forms of Se compounds enhanced its chemopreventive effect. Future studies will expand the use of three Se-containing compounds to four and demonstrate similar effects in xenograft mice.

Chelsea Moody, Dixie State University Life Sciences A relatively new pathogen, chytrid fungus, has been a major cause of decline in amphibians worldwide. This pathogen has been found on Canyon Tree Frogs in Zion National Park. Earlier data suggested that chytrid did not affect populations of Canyon Tree Frogs in Zion National Park. We predicted that since the populations weren’t impacted by the presence of the fungus, there must exist a mechanism by which the frogs rid themselves of the infective agent. To test this prediction, we captured and swabbed ten frogs in each of nine canyons in Zion National Park during the summer of 2013. Swabs were sent to the San Diego Zoo to be analyzed for the presence of chytrid DNA. Chytrid infection rates and population sizes were compared with data from previous years. As expected, the data showed that two of the three infected canyons experienced declines in the percentage of frogs testing positive for the fungus. Thus, these frogs must possess a mechanism to survive this pathogen, whereas most amphibians do not. Our results may prove helpful to other biologists seeking to understand how amphibians can survive this pathogen.

Eric Swenson, Dixie State University Life Sciences Underwater invasive species such as mussels and algae attach to submersible substrates that are advantageous for growth, and often include recreational boats that are frequently moved from one waterway to another. This can lead to rapid and uncontrolled spread of the invasive species. Through the use of newly developed ionic surfactants, growth and attachment of species on submersible surfaces can be inhibited. New surfactants have been incorporated into the final coating of typical product sealants to prevent the attachment of various marine organisms. By integrating the surfactant into the coating, an increase in the usefulness and longevity of effective inhibition is expected, as compared to commercially available alkali anti-fowling agents that are applied after the sealing process. It is hypothesized that the adherence properties possessed by marine organisms will be compromised by the introduction of ionic surfactants through changes in the chemical makeup of the exposed surfaces. The ultimate goal is to develop a substrate surface in which there is no affinity for attachment and/or causes fatality to the organism. If the desired outcome is reached, the potential benefits that ensue could create drastic improvements in areas of invasive species prevention and management in the desert southwest fresh-water lakes. Additionally, extension of the surfactant application to metal surfaces could have significant impacts on efficiency in water treatment systems, as well as cargo shipping in saltwater environments.

David Baird, Utah Sate University Life Sciences We obtained from the Bureau of Land Management (BLM) 30 years of monthly waterfowl population surveys completed at Pariette Wetlands in the Uintah Basin, Utah between 1980 and 2010. The Pariette Wetlands are the largest wetlands managed by the BLM within the lower-48 states and are comprised of 4,033 acres of land. Pariette Wetlands is surrounded by about 6,000 square miles of land where oil and gas production is the major activity. This waterfowl refuge is a significant location for migrating waterfowl species within the Pacific Flyway and provides important summer habitat for resident waterfowl. Our objectives were to determine what the trends were for waterfowl population abundance, occupancy, and species richness.

Albert Pope, Utah Valley University Life Sciences Few animals are capable of using the creosote plant, Larrea tridentate, as food because of a high level of toxic secondary compounds. Some exceptions to this rule are Neotoma lepida and Dipsosaurus dorsalis which are both capable of sustaining themselves on this desert bush. In 2013, Magnanou et al helped identify heightened transcription of genes correlated with digestion of creosote in N. lepida. Building upon their findings, we explore whether the genes for digesting creosote are under an elevated evolutionary rate for D. dorsalis. We have obtained transcriptomes from whole blood of four Iguaninae species: Ctenosaura pectinata, D. dorsalis, Sauromalus ater, Cyclura lewisi yielding an average of 4 GB of DNA sequence data (~51,000,000 fragments) each. Using Velvet in Sequencher we assembled these data, recovering greater than 6000 unique RNA transcripts per transcriptome. We search through the contigs to identify genes in Iguaninae transcriptomes that are homologous to those showing differential expression in Lepida. Using BLAST, we retrieve homologous genes from the public NCBI database of Anolis carolinensis and other reptiles. Lastly we construct phylogenetic trees of each gene and investigate the rate of change along each reptile lineage.

Cameron Haas, Brigham Young University Life Sciences The influenza A virus contains a proton-selective ion channel, A/M2, through which acidification of the cell is induced. A/M2 is a homotetramer (consists of four identical helices) consisting of 97 residues and activated by low pH levels. Mutations in the amino acid sequences may induce resistance to channel inhibiting drugs. It is believed that residues 26, 27, 30, 31, and 34 are the major contributors of drug resistance, but other nearby residues may prove important as well. The A/California/04/2009 version of the influenza virus is sensitive to the drug AK-11, while its M2 channel is not. The A/Udorn/307/1972 with the S31N mutation M2 channel has been shown to have reduced sensitivity to amantadine compared to its wild type. While both contain a D (aspartic acid) at residue 21, A/Puerto Rico/8/1934 has a mutation from D to G (glycine). The A/Puerto Rico/8/1934 virus A/M2 contains mutations S31N and V27T and has shown sensitivity to the AK-11 drug, but the mechanism of inhibition of the A/M2 channel has not been verified. In these experiments we will be identifying sensitivity to AK11 of A/Udorn/307/1972 with the S31N mutation as well as inducing double mutations with S31N at residues 27 and 21 in the A/M2 from the virus and measure sensitivity by electrophysiological recordings in oocytes of Xenopus laevis. By doing so we may identify the role of these residues in drug resistance and the effects of these amino acid mutations, while verifying the A/M2 channel as the mechanism of acidification inhibition and drug sensitivity. We hypothesize that either D21G, V27T or both mutations causes drug sensitivity in M2 S31N, explaining the sensitivity of A/Puerto Rico/8/1934 to AK-11.

Whitney Badal, Brigham Young University Life Sciences Light therapy has been utilized to treat alcoholism and opiate-dependent rats as well as ameliorating symptoms of Parkinson’s disease. As both addiction and Parkinson’s Disease (PD) are often associated with decreased dopamine transmission in the striatum, it is likely that light therapy is able to increase dopamine release. A similar technique called near-infrared light treatment has also been shown to be effective in mice in restoring the function of dopamine cells in the substantia nigra pars compacta (an area associated with PD). A possible explanation for this is that light catalyzes the formation of neuromelanin. It is likely that neuromelanin is a neuroprotective cellular agent that is able to reduce damage caused by reactive oxygen species. Using UV-IR spectrophotometry, we show that in the presence of photostimulation, dopamine (0.3-30 uM) oxidizes and polymerizes into neuromelanin. Since hydrogen peroxide catalyzes this formation of neuromelanin, it is likely that this is a radical-polymerization reaction, suggesting that neuromelanin may be a radical scavenger. Additionally, the presence of the selective iron chelator desferrioxamine, the calcium chelator EGTA, or lack of calcium in the artificial cerebral spinal fluid markedly reduces the formation of neuromelanin. Using fast scan cyclic voltammetry in mouse horizontal and/or coronal brain slices, dopamine release in the nucleus accumbens core was enhanced by light exposure, in particular UV and short-wavelength visible light. These findings indicate that both iron and calcium are necessary for melanization in neural tissues and that light-induced melanization enhances dopamine release, suggesting a physiological role for melanization in synaptic transmission.

Chase Barker, Utah Valley University Life Sciences Central Research Question: Phylogenetic relationships of mayflies are still not very well known, however molecular and morphological data have begun to shed light on the relationships of these insects (Ogden et al. 2009). Our central question is to elucidate the phylogenetic relationships within the mayfly family Baetidae.

Danielle Holliday, University of Utah Life Sciences Intrauterine growth restriction (IUGR) induces visceral obesity in adulthood, specifically among males. In male rat offspring, IUGR increases visceral adipose tissue (VAT) over subcutaneous adipose tissue (SAT). VAT and SAT functions are regulated by estrogen signaling, and suppressed estrogen signaling contributes to obesity development. Estrogen signaling is composed of estradiol and estrogen receptor alpha (ERα) and beta (ERβ). Estrogen receptors regulate the expression of several obesity related genes, such as lipoprotein lipase (LPL). However, the effects of IUGR on estrogen serum levels and signaling in the adipose tissue are unknown.

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.

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.

Alysa Fratto, Westminster College Life Sciences Although the idea of life on other planets is mused over by many, the scientific study of the potential for extraterrestrial life did not begin until the mid-1950s (SETI, 2013). Since then, many technological advancements have been made that make the study of life on other planets simpler, however it is inherently difficult to study the potential for life in an environment that one cannot access. To address this issue, scientists look on Earth for extreme environments that mimic those found elsewhere in the universe.

Tamara Fox, Weber State University Life Sciences Clostridium botulinum has been implicated in cases of infant botulism across the United States. It is recommended that infants under the age of one year not be fed honey because of the presence of C.botulinum spores. The goal of this project is to determine whether honey produced in small and large apiaries in Utah contain varying amounts of toxin producing C. botulinum. Honey samples will be collected from hives maintained in Utah and tested for the presence of toxin producing strains of C. botulinum. Samples will be dissolved and centrifuged to isolate the spores and then superheated to release the DNA. Testing will then be done through a multiplex polymerase chain reactions (PCR) using primers specific for 16s rRNA, Clostridia species, and toxins A, B, E, and F. The presence and type of toxin producing Clostridia species will be compared with a Chi-Squared Test of Independence. Research will be completed by February of 2014 and we expect small apiaries will have a lower frequency of toxin producing C. botulinum strains than large apiaries and that toxin phenotype will vary between the two groups. The results will increase understanding on the variance of C. botulinum in Utah honey and will contribute to further research on this topic.

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.

Robyn Kira Omer, Utah Valley University Life Sciences Peak density, which is the number of peaks and valleys in a specified spectral range of high-frequency (HF) ultrasound, correlates to breast pathology in lumpectomy specimens. It has been a question in both previous and current studies, however, whether the thickness of a sample has an independent effect on the peak density. The objective of this study was to discover any correlation, if any, between specimen thickness and peak density in HF ultrasound measurements (10-100 MHz). Phantoms were fabricated from a mixture of water, gelatin, and soluble fiber. Polyethylene microspheres (180-212 micrometer diameter) were embedded into half of the phantom specimens at 0.0003% concentration to simulate tissue heterogeneity. The other phantoms were devoid of microspheres to provide control measurements. Seventy two pitch-catch measurements were acquired in triplicate using 50-MHz transducers, a HF pulser-receiver, and a 1-GHz digital oscilloscope. The waveforms were analyzed to provide spectra and the resulting peak densities were determined. The results indicate that no significant correlation exists between specimen thickness and peak density. The coefficients of correlation for the microsphere and control specimens were 0.366 and 0.652, respectively. The peak density values were most consistent within the control specimens, ranging from 1 to 4. The peak densities for the microsphere phantoms had a greater range of values, varying from 1 to 8. It is believed that the wide variation in peak density for the microsphere phantoms was due to clustering of the microspheres. Future studies will include looking at previous phantom and tissue studies to further investigate the apparent lack of thickness-peak density correlation.

Adam Jorgensen, Brigham Young University Life Sciences Arrhythmia is a serious heart defect that effects 14 million people in the United States. It is characterized by irregular rhythm in the electrical impulses of the heart. Arrhythmia can cause sudden cardiac arrest and stroke. Recent developments in cardiac ablation have helped in the treatment of arrhythmia. Cardiac ablation works by scarring tissue in the heart, thus preventing abnormal electrical signals to travel through the myocardium. The three-dimensional map created in this project will improve the accuracy of cardiac ablation by offering a more dynamic view of the human heart and associated nerve branches. By properly articulating the intricate nerve branching of the heart, surgeons will be able to better target the nerves themselves when scarring heart tissue, thus allowing a less invasive procedure.

Bradley Prince, Brigham Young University Life Sciences Learning and memory occur due to adaptive brain changes in response to our environment. These changes are mediated by synaptic plasticity, particularly within the hippocampus, where spatial and declarative memories occur. Plasticity can either strengthen or weaken synapses, known as long-term potentiation (LTP) or long-term depression respectively. While many forms of synaptic plasticity are N-methyl-D-Aspartate receptor-dependent, recently endocannabinoids were identified to mediate several new forms of hippocampal synaptic plasticity. Endocannabinoids bind to receptors such as cannabinoid receptor 1 (CB1) and transient receptor potential vanilloid 1 (TRPV1), and mediate several forms of plasticity, including in the hippocampus. However, new research has demonstrated a non-CB1/TRPV1-dependent endocannabinoid synaptic plasticity in the hippocampus. While the receptor(s) involved is currently unknown, several potential candidate receptors that bind the endocannabinoid anandamide have been identified. These are orphan G-protein coupled receptors (GPRs) whose distribution in the brain and/or function is unknown. GPR55 is of particular interest as it activates second message systems, including increasing intracellular calcium. Using quantitative RT-PCR, electrophysiological and memory behavioral tasks we examined hippocampal GPR55 expression and function. GPR55 is indeed expressed in hippocampus of both rats and mice. Cellular expression is currently being examined and appears to be rare in interneurons and more likely expressed by pyramidal cells. Interestingly, application of the GPR55 agonist LPI (2 µM) to wild-type mice demonstrates a decrease of LTD in brain slices. This LPI effect was not noted in GPR55 knock-out mice in the presence of LPI. This data suggest GPR55 is physiologically relevant in the hippocampus. This is the first direct evidence we are aware of that a novel endocannabinoid receptor directly effects hippocampal LTD. Because neurodegeneration that affects memory is typically associated with an increase in LTD, this provides a potential target to slow the advance of diseases such as Alzheimer’s.

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.

Chance Christensen, Utah State University Life Sciences Affective disorders such as depression, phobias, schizophrenia, and post-traumatic stress disorder impair the ability to time in the seconds-to-minutes range, i.e., interval timing. According to the Relative Time-Sharing (RTS) model, presentation of task-irrelevant distracters during a timing task results in a delay in responding suggesting a failure to maintain subjective time in working memory, possibly due to attentional and working memory resources being diverted away from timing. Given that some anxiolytic medications have beneficial effects on attention and working memory, e.g., decreasing emotional response to negative events, we hypothesized that they would result in a decreased effect of distracters on the timekeeping abilities. We investigated the effect of acute administration of anxiolytic medication when anxiety-inducing task-irrelevant distracters were presented during an interval timing task, using methods similar to Matthews et. al. (2012) Frontiers in Integrative Neuroscience 6(111): 1-12. Results are discussed in relation to the brain circuits involved in RTS of resources, and the pharmacological management of affective disorders.

Josh Harvey, Brigham Young University Life Sciences Soil CO2 flux represents an important pathway of carbon transfer from ecosystems to the atmosphere. Soil CO2 flux can be altered by global warming-driven changes in seasonal temperature and water availability. Subalpine ecosystems have high levels of carbon in their soils that are stabilized by low temperatures and low microbial activity during long and snowy winter seasons. Subalpine ecosystems can be important sinks for carbon, storing carbon that otherwise would be in the atmosphere contributing to global warming. In our study we show how changes in temperature and water availability during springtime increase the levels of subalpine carbon output. So long as the carbon outputs outweigh carbon inputs, increases in soil flux would amplify global warming. The amplification of global warming would loop back to affect soil fluxes again (by raising temperatures, melting snow earlier, and changing precipitation patterns) thus creating a positive feedback system. Understanding what feedbacks are present in a climate system and their underlying mechanisms will improve our forecasts of changes in atmosphere chemistry and temperature.

Logan Warner, Utah Valley University Life Sciences High-frequency ultrasound (20-80 MHz) has been found to be sensitive to a range of pathologies in excised breast tissue before fixation in formalin or other formaldehyde analogues. Formalin fixation, however, may alter the structure and rigidity of a sample so that data gathered using high-frequency ultrasound after fixation may no longer be viable for research purposes. This limits the amount of time researchers may conduct tests, so preservation via simple sugars is being considered. Numerous studies have been conducted using sucrose, trehalose, or glucose as cryoprotectants for cells and simple tissues. The objective of this study was to test the sensitivity of high-frequency ultrasound to changes in the microstructure, stiffness, and cellular integrity of tissue samples due to cryopreservation with these sugars. Domestic pig heart tissue was placed in aqueous solutions of sucrose, trehalose, and D-(+)-glucose. The specimens were refrigerated and observed over time using high-frequency ultrasound to detect tissue damage. The results of this study suggest that cryopreservation with sugars will not only allow more time for researchers to conduct ultrasonic tests on surgical specimens, but also that high-frequency ultrasound could potentially be used as an assay to measure tissue degradation in preserved living tissues such as transplant organs.

Hillary Hansen, University of Utah Life Sciences Type 1 diabetes is an autoimmune disease where pancreatic β-cells are destroyed, resulting in insulin deficiency. Generating new β-cells from stem cells for treating diabetes will benefit from understanding their development in vivo. Pancreatic β-cells, along with all other pancreatic lineages arise from multipotent pancreatic progenitor cells (MPCs). Previous studies demonstrate that the structural and signaling protein β-catenin is required for the development of the exocrine acinar lineage. β-cells still differentiate in the absence of β-catenin, however, β-cell mass is dependent upon β-catenin. We determined that this dependency reflects a role for β-catenin in the maintenance of MPC patterning as well as for expansion of the progenitor pool. Whether our observed effects are due to the signaling or structural function of β-catenin remains unknown, and is the focus of this research. Using mouse genetics we are able to separate the structural and signaling functions of β-catenin. Eliminating both functions in PBKO (full knockout) mice produces decreased β-cell mass and irregular patterning. Decreased β-cell mass is also observed in PBsKO (signaling deficient) mice, though patterning remains unaffected. This suggests that pancreas growth is dependent upon canonical Wnt/β-catenin signaling, and that maintaining progenitor identity requires the structural role of β-catenin. Elucidating distinct roles for β-catenin could be used to drive stem cell-derived MPCs to expand and differentiate to the desired pancreatic cell fate.

Michael Naegle, Brigham Young University Life Sciences Dermaptera is a comparatively small order of insects with approximately 1800 species placed in three suborders. While the majority of earwig species are placed within the suborder Forficulina and are free-living with forceps-like appendages, two dermapteran lineages have a very unusual morphologies and life histories. The viviparous Hemimerina live epizoically on giant rats in tropical Africa where they feed on fungi growing on the rats’ skin. Hemimerina lack eyes and wings and the cerci are filiform. The viviparous Arixenina are associated with bats in Malaysia and the Phillippines, and they feed on bat skin gland secretions. They have reduced eyes, are wingless, and possess straight cerci. The phylogenetic position of the suborders Arixenina and Hemimerina relative to Forficulina have previously been unclear; however preliminary analysis suggest the phylogenetic position of the suborders Arixenina and Hemimerina are nested within Forficulina, with ectoparasitism evolving multiple times within this order. We generated DNA sequence data from three nuclear (18S, 28S and H3) and two mitochondrial (COI and TUBA) genes for representatives of all three suborders and outgroups. A phylogeny was reconstructed to address the following questions: (1) Does Hemimerina + Arixenina form a monophyletic group and support a single origin of parasitism or are there multiple origins of parasitism? (2) Is Forficulina monophyletic with respect to these parasitic lineages? (3) Are morphological similarities shared by the ectoparasitic forms synapomorphic or homoplasious characters?

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.