2014 Abstracts
Do Canyon Tree Frogs in Zion National Park Possess a Mechanism to Defend Against Chytrid?
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.
Attachment reduction of invasive species with submersible substrates
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.
Utah Valley University/Huntsman Cancer Institute Collaborative Breast Cancer Study: High-Frequency Ultrasound for Margin Assessments
J Andrew Chappell, Utah Valley University Life Sciences In a joint effort with Huntsman Cancer Institute at the University of Utah, students from Utah Valley University are using high-frequency (HF) ultrasound to test the pathology of surgical margins from breast cancer conservation surgery. The method, developed by Dr. Timothy E. Doyle, provided significant results in a NIH-funded 2010 feasibility study. The results of the study indicated that peak density, the number of peaks and valleys in the HF ultrasonic spectrum, correlates to breast tissue pathology. This technology would allow surgeons to test – in the operating room – whether a surgical margin was clean or if cancer still remained in the margin. This advancement would decrease the amount of return surgical visits a patient must undergo, reduce costs for patients and hospitals, reduce breast cancer recurrence rates, and ultimately increase the survival rate of patients with breast cancer. During the ultrasonic testing, the students work in a team of four in a room outside of the surgical suite. Specimens are brought in by the surgeons’ team and tested immediately following resection. The margins are approximately 3x20x20 mm in size, and are oriented using a small staple inserted by the surgeon in one corner and a stitch on one side. The margin is tested at specific locations depending on the size of the margin and then sent to pathology for analyses. Pathological results and HF ultrasound results will be compared for correlation at the end of the study, which is expected to last about one year. The study will include approximately 80 patients, 360 tissue samples, 1400 tested locations, and 4,300 data points. The goal of the study is to evaluate the accuracy of the method in determining margin pathology. If successful, the method will be moved into clinical trial.
Standing on the shoulders of Woodrats: Adaptive Evolution in Desert Iguanas
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.
The effect of residue 21 on drug resistance of the A/M2 proton channel of the influenza virus
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.
Physiologically Relevant Oxy-Radical Formation of Neuromelanin by Photostimulation: Effects of Iron and Calcium
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.
Intrauterine Growth Restriction Alters Estrogen Serum Levels and Signaling in Rat Adipose Tissue in a Sex Dependent Manner
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.
Using breast cancer subtypes as a model for detecting cytoskeletal dysfunction in Alzheimer’s disease
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.
3D printing from MRI data of stroke and Alzheimer’s disease subjects: An educational model of neurologic disease
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.
Life at the Extremes: Finding Earthly analogs for potential life on Mars
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.
Rapid adaptation of d2 dopamine receptor responses following acute ethanol
Joseph Linzey, Brigham Young University Life Sciences Dopamine (DA) D2 receptor expression parallels DA levels in the brain and these autoreceptors on DA neurons been shown to be modulated by long-term ethanol exposure. We have previously demonstrated that VTA GABA neurons also express D2 receptors, and that DA and D2 receptor agonists markedly enhance the excitability of VTA GABA neurons, opposite to their well-known inhibition of DA neurons. Most importantly, D2 receptor antagonists block ethanol inhibition of VTA GABA neurons and D2 receptor expression in VTA GABA neurons down-regulates with chronic ethanol. This study evaluates short-term D2 receptor adaptation in VTA GABA neurons and in DA release in the nucleus accumbens (NAc) by acute ethanol. In electrophysiology studies in anesthetized rats, periodic iontophoretic application of DA, or the D2 agonist quinpirole, markedly enhanced VTA GABA neuron firing rate, which was initially inhibited by ethanol, but resulted in latent and marked rebound excitation 30-60 min following injection. Using fast scan cyclic voltammetry (FSCV), we evoked DA signals in the core of the NAc by electrical stimulation of the medial forebrain bundle at the level of the lateral hypothalamus (60 Hz, 24 pulses). Intraperitoneal (IP) administration of ethanol (1.0-3.0 g/kg) dose-dependently decreased the amplitude of the MFB-evoked NAc DA signal. IP administration of the D2 antagonist eticlopride (1 mg/kg) markedly increased (250%) the amplitude of the evoked DA signal. When ethanol was administered after eticlopride it increased the amplitude of the DA signal an additional 42%. These findings suggest that ethanol induced decreases in evoked DA release may be due to autoreceptor feedback. Work is in progress to evaluate the short-term expression of D2 receptors in VTA GABA neurons following acute ethanol and to evaluate the effects of ethanol-induced short and long-term adaptations in VTA GABA neuron D2 expression in mediating ethanol effects on DA release in the NAc.
Variance of toxin producing clostridium botulinum in utah honey
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.
Biological effect of of oils spill dispersant corexit
April Moorer, Weber State University Life Sciences Corexit is a dispersant used in the gulf of Mexico as a reactive measure to counteract the oil spill of April of 2010. Studies reveal that toxicity is produced and has impacted marine life. Research shows that reproductivity is diminished as a consequence. Paralysis, tumor development, and fatalities are also proven to occur. The purpose of this experiment is to study effects on the physiological structure of brine shrimp at various life stages resulting from the exposure to toxicity induced by corexit.
Functional Switch in GABA(A) Receptors on VTA GABA Neurons by Chronic Ethanol
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.
Correlation between phantom thickness and peak density in high-frequency ultrasonic spectra
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.
Assessment of Environmental Awareness among Utah Valley University Students
Michaelle Cadet, Utah Valley University Life Sciences Utah County, Utah has an estimated population of 540,000 residents and is considered to be a non-attainment area for criteria pollutants such as PM-10 and CO. High levels of these contaminants may increase the risk of respiratory diseases. Additional environmental issues exist including water contamination and eutrophication of Utah Lake. These environmental issues are frequently on the news and warnings are issued by the Department of Environmental Quality notifying citizens of the potential health concerns associated with environmental pollution. With these announcements, it is expected that Utahans are acutely aware of environmental issues, particularly, in the academic settings. The purpose of this study was to investigate the status of environmental awareness among students at Utah Valley University and to correlate the results to socio-demographic categories. Utah Valley University, located in Utah County, is a public institution of higher education with approximately 30,000 registered students. Data for this study was collected through a survey using a multistage sampling technique with population stratified based on colleges and schools within the university. Sample size included approximately 1,000 students. The survey contained 12 environmental questions relating to recent local, national and international media exposure. Standards and protocol of the International Research Board were employed. We hypothesize that married, educated, religious males will positively correlate with higher levels of environmental awareness, but will be less than atheists. Additionally, those identifying with the Republican Party will have lower levels of awareness. No significant difference will be found between majors. Furthermore the young, poor and ethnic populations will be less aware than their more affluent counterparts. Results of this study will be used to inform residents of environmental issues and the associated health concerns. Additionally, this study will be used to inform legislators about the importance of environmental education in the community.
Size, Personality, and Evolution: Examining Predictions in Two Live-bearing Fishes
Jeremy Rehm, Brigham Young University Life Science The recent surge of interest in personality differences between individuals of a single population or members of differing populations has generated numerous new hypotheses that may aid in elucidating patterns of ecology and evolution that were previously considered improbable. Two hypotheses relevant to fish biology relate the size of an organism from a certain predation environment to the level of boldness it exhibits. The first of these (predation hypothesis) predicts small individuals living with predators should not express boldness comparable to their larger counterparts, whereas the other (metabolic hypothesis) predicts the exact opposite. Our study investigated these hypotheses using two sister-taxa fish species in Panama (Brachyrhaphis roseni and B. terrabensis) that exhibit two size classes (large and small) and live in differing predation environments. Additionally, because males are smaller than females in both species, we could look at size-boldness relations within each species. The study, as in others, defined boldness as the amount of time for an individual to emerge from a shelter and into an unfamiliar territory. When the species are analyzed collectively, our results support previous findings that fish from high-predation environments tend to be bolder than those without predators; males tend to be bolder than females; and both mass and standard length positively correlate with boldness. However, within species analyses find that mass and standard length have no significant relation to boldness, and gender was only significant in the predation-exposed B.roseni, where males were bolder. These interesting findings contrast with previous studies, and lead us to question the value of these size-related hypotheses in the process of speciation and, ultimately, evolution.
Dna Based Identification and Prevalence of Cestode Parasites in the Brine Shrimp (Artemia franciscana) from Great Salt Lake, Utah
Ethel Tackie-Yarboi, Westminster College Life Sciences The brine shrimp, Artemia franciscana are an important source of nutrients for many of the over 15 million migratory birds that visit Great Salt Lake (GSL) in Utah each year. As well as being a source of food, the brine shrimp are an intermediate host to cestode parasites that infect many of the bird species. Although the effects of cestode infection in brine shrimp and the contribution of brine shrimp to cestode circulation in birds have been studied, little research has yet addressed the rate of cestode infection or molecular phylogeny of these cestodes. We collected brine shrimp from three sites in GSL and tested individuals for cestode infection using previously identified and newly designed cestode specific PCR primers that amplify the 18S ribosomal RNA gene. Our preliminary results showed that the Spiral Jetty site from the North arm of GSL had a 2% infection rate, the Antelope Island site from the South arm had a 45% infection rate, and the shrimp collected at the Black Rock site, also in the South arm, had a 32% infection rate using our cestode specific PCR assays. We also have preliminary DNA sequencing results that demonstrate that we are amplifying cestode DNA, which is most closely related to members of the genus Hymenolepis. Our data suggest that there may be a higher prevalence of cestode infection in the shrimp in the South arm than those from the North arm of the Great Salt Lake. Our goal is to extend our study in order to better identify the species of cestodes that infect brine shrimp using further DNA sequencing and to expand our infection rate samples to better estimate the percentage of the brine shrimp population that is infected by the cestode parasites, as well as test samples from several years.
PP2A inhibition using LB1 negates palmitate-induced reductions in nitric oxide production in endothelial cells
J David Symons, University of Utah Life Sciences Cardiovascular complications (e.g., arterial dysfunction) are more prevalent in patients with type 2 diabetes (T2DM). Patients with T2DM have elevated levels of circulating free fatty acids (FFAs). We have shown that when bovine aortic endothelial cells (BAECs) are treated with the physiologically relevant FFA palmitate, protein phosphatase 2A (PP2A) activity increases, phosphorylated endothelial nitric oxide (NO) synthase (eNOS) to total eNOS (p-eNOS:eNOS) decreases, and metabolites of NO production decrease. NO is an important endothelial-derived relaxing factor that is vasculoprotective. As such, FFA-induced, PP2A-mediated reductions in p-eNOS:eNOS and NO production might explain why vascular complications are more common in pathologies associated with lipotoxicity e.g., T2DM and diet-induced obesity. Recently we showed in BAECs that if PP2A is inhibited using okadaic acid (OA), palmitate-induced increases in PP2A activity, and reductions in p-eNOS:eNOS and indices of NO production are negated. We sought to translate these finding from BAECs to the intact organism. However, OA cannot be used in vivo. Lixte Biotechnology 1 (LB1) is a PP2A inhibitor that has been used in vivo in the context of cancer research. The purpose of this study was to determine the efficacy of LB1 under our experimental conditions, with the long-range goal of using LB1 in mice. Further, we used this opportunity to optimize the measurement of NO directly using electron paramagnetic resonance spectroscopy (EPR). BAECs were treated for 3 h with vehicle (V), 500 µM palmitate (P), 4 µM LB1, or P + LB1 (n=10 per treatment). P increased (p<0.05) PP2A activity (50±12%), and decreased (p<0.05) p-tyr307:PP2A (29±9%; redundant indicator of increased PP2A activity), p-eNOS:eNOS (30±3%), and NO production (27±9%). All P-induced effects were prevented by concurrent treatment with LB1. Future experiments will determine whether chronic treatment of mice with LB1 is capable of suppressing PP2A activity in intact arteries.
Edge effect on vegetation type and cover along a popular recreational trail
Cynthiann Heckelsmiller, Weber State University Life Sciences Heavy foot traffic compacts soil, leading to decreased gas exchange, water permeability, and reduced nutrient cycling. Plant communities are defined by the availability of nutrients, water, and other resources.
Mutational Analysis of the Serine Chemoreceptor In Escherichia coli
Jordan Fenlon, University of Utah Life Sciences Tsr, the serine chemoreceptor for E. coli, is a transmembrane protein with a periplasmic sensing domain and cytoplasmic adaptation and kinase control domains. The focus of my research project is Tsr residue A413, located in the cytoplasmic tip of the receptor’s kinase control domain. The project involves characterization of mutant Tsr proteins containing amino acid replacements at residue 413. Based on previous work in the Parkinson lab, this residue is thought to play a key role in Tsr signaling by regulating the dynamic motion of the tip.
The effects of imidacloprid on Atremia franciscana
Sean Studstill, Weber State University Life Sciences Imidacloprid is a popular systemic insecticide that has been applied to our staple crops for two decades. According to the EPA, it is persistent in the environment and at risk of effecting non-targeted organisms. Imidacloprid is an insect neurotoxin; however it is also known to be toxic to various aquatic species in concentrations as low as 37 ppb. Ingestion of imidacloprid causes paralysis in organisms through the blockage of postsynaptic nicotinic cholinergic receptors. We sought to find out how toxic imidacloprid is to brine shrimp and what kinds of physiological reactions occur upon exposure.
Development of sensitive ELISA and qPCR assays to quantitate levels of dust mite antigens in homes in Utah with and without swamp coolers
Evan Campbell, Brigham Young University Life Sciences Asthma is a chronic allergic disorder manifest by airway restriction due to inflammation, bronchoconstriction, and increased respiratory mucous secretion. As many as 300 million people worldwide are affected by asthma and its prevalence is increasing primarily in countries experiencing urbanization and Westernization. Asthma is currently the most common chronic illness among children in the U.S., and the third leading cause of hospitalization for children aged 0 – 15 yrs. Reservoir dust collection and area air sampling are the two primary methods of measuring allergen levels in house dust. Allergen sensitization leading to asthma is thought to occur prior to age six while the immune system is still naïve. In the case of the dust mite allergen Der p1, the exposure window may be as early as age two. However, little evidence is available to establish a dose–response relationship between inhalation exposure and early immunological sensitization to allergens. Temperature and relative humidity play a major role in dust mite survival and proliferation and indoor humidity above 50-60% in arid environments has been shown to support dust mite populations. Evaporative “swamp” coolers cool air by adding humidity to it and can create favorable environments for dust mite survival. We are working to determine how much swamp coolers contribute to dust mite levels in Utah by quantitating dust mite allergen levels in homes with and without swamp coolers. In order to do this we are developing sensitive ELISA and quantitative PCR methods to allow us to determine levels of exposure even when low levels of dust are collected.
Comparative Analysis of Small Transducers and Large Transducers using High-Frequency Ultrasound on Phantom Breast Tissue
Madison Peterson, Utah Valley University Life Sciences High-frequency (HF) ultrasound in the 20-80 MHz range has recently been found to be sensitive to pathology in tissue margins from breast cancer surgery. In order to improve the resolution and sensitivity of this method, however, transducers need to be employed that have piezoelectric elements that are smaller than those currently in use. The purpose of this study was to determine if small element transducers (Blatek pachyometer, 50 MHz, element diameter < 2 mm) produce similar results as those obtained from large element immersion transducers (Olympus NDT, V358-SU, 50 MHz, 6.35-mm diameter active element). Ultrasonic tests were performed on 10 phantom breast samples made of Knox gelatin base and soluble fiber (Metamucil), five of which contained chopped nylon fibers and five which contained polyethylene microspheres. Pulse-echo and through transmission measurements using a HF square-wave pulser/receiver (UTEX, UT340) and a digital storage oscilloscope (Agilent, DSOX3104A, 1 GHz, 4 analog channels) were acquired from a total of 3 sites per phantom in triplicate, first testing all specimens with the large transducers then again with the small transducers. Specimens were marked with India ink for location and accuracy of testing. The density of peaks in the ultrasonic spectra of the small transducers paralleled those of large transducers. Results from HF ultrasonic measurements of phantom breast tissue obtained from small transducers compared to the large transducers indicate that they produce statistically comparable peak densities. In breast conservations surgery it is crucial to excise all cancerous tissue to prevent recurrence. This method could provide in vivo cancer detections in margins and allow for more precise excision of tumors and cancerous tissue preventing the need for subsequent surgeries and thus, less risk, reduced pain and suffering, lower costs and better outcomes for breast cancer patients.
Macroinvertebrate Assemblage as an Indicator of Urban Stream Health
Mena Davidson, Westminster College Life Sciences Urban stream syndrome is the phenomenon of stream degradation as streams run from their sources through urban areas, which is exhibited by nutrient loading, decreased dissolved oxygen, changes in channel structure, and increased turbidity and rapid flow events. This can have a direct negative effect on our recreation, drinking water, and the ecosystems surrounding the streams. To discover if urban stream syndrome occurs in the Salt Lake Valley, we monitored pH, turbidity, dissolved oxygen, dissolved nitrates, and collected macroinvertebrates in three streams monthly. We analyzed total abundance, species diversity, and percent pollution sensitive species to assess the macroinvertebrate communities, as known indicators of water quality. Preliminary data shows a significant decrease in percent sensitive species in the urban areas as compared to the nonurban areas over 10 sampling periods. We found decreased biodiversity and fewer sensitive species in urban areas, although we found no difference in total abundance. These findings indicate that urbanization in the Salt Lake Valley leads to degradation in riparian ecosystems and suggest that further investigation is needed to identify the mechanisms leading to this degradation.
Exercise Reverses Stress-induced LTP Reduction in the Hippocampus
Teresa St. Pierre Nufer, Brigham Young University Life Sciences Acute stress has been shown to decrease Long-Term Potentiation (LTP) in the CA1 region of the mouse hippocampus. Stressed animals also show signs of anxiety and suffer decreases in spatial memory tasks such as object recognition and maze navigation. Conversely, exercise has been shown to increase spatial memory task performance in mice, attenuate anxiety-like behaviors and enhance neurogenesis and LTP in the dentate-gyrus. While the effects of stress and exercise have been examined independently, there is currently a lack of experimental evidence that connects how stress and exercise, when experienced by the same animal, might modulate LTP in the CA1 region of the hippocampus. In our ongoing study, mice have been separated into a control group, a stress group (restraint and tail-shock), and an exercise with stress group where mice have voluntary access to a running wheel (for 30 days) before undergoing the stress protocol.
The effect of UV radiation on lichen metabolism
Colby Pearson, Utah Valley University Life Sciences Many lichens synthesize unique secondary metabolites, such as atranorin (AT), which may serve as photo-protection against harmful UV radiation. Our study investigates changes in metabolism and internal levels of atranorin in lichens under various light conditions and atranorin supplementation. We will expose 60 Physcia adscendens (Fr.) H. Olivier lichen thalli to one of three different light levels (UV +PAR; PAR only; and neither UV nor PAR). Half of our experimental thalli will be supplemented with AT. Lichen biomass, AT concentration via HPLC, and photosynthetic and respiration rates will be measured before and after the experiment to measure metabolic responses of both supplemented and non-AT-supplemented thalli under each light level.
Pamphlet and Survey of Common Insects of Capitol Reef National Park
Robert Erickson, Utah Valley University Life Sciences Although the insect fauna of the Colorado Plateau region are somewhat well known, our specific understanding of the arthropod biodiversity in Capitol Reef National Park is sparse.
Differentiating Molecular Subtypes of Breast Cancer Using High-Frequency Ultrasound
Caitlin Carter, Utah Valley University Life Sciences High-frequency (HF) ultrasound (20-80 MHz) has been previously used to detect differences in microstructures and cell materials of different breast tissues types. These differences were used to distinguish between benign and malignant pathologies in different breast tissues. This same technology is predicted to be able to improve methods of detecting changes in cellular activity before changes in pathology take place. The purpose of this study was to use HF ultrasound to detect changes in the actin cytoskeleton, extracellular matrix (ECM), and integrin signaling, therefore differentiating the molecular subtypes associated with these changes in cell biomechanical properties. It is predicted that these cellular changes will also be associated with changes in the ultrasonic properties of breast cancer cells. The ability to rapidly and inexpensively detect the genetic changes or molecular subtypes of breast cancer would greatly impact and personalize patient treatment as well as provide more precise surgical removal of malignant and premalignant tissue. In order to test this hypothesis, four different breast cancer molecular subtypes including luminal A, luminal B, Her2+, and basal (triple negative) were grown as monolayer cell cultures. These subtypes were chosen because of their range of aggressiveness (luminal A as least aggressive and basal as most). After growth at different seeding levels, cell cultures were tested with a HF ultrasound system using a 50 MHz, 6.35-mm diameter immersion transducer and pulse-echo transmission. The data was compared to simulations using multipole expansions which predicted ultrasonic scattering based on possible variations in the biomechanical properties of malignant cells. The analyzed data showed differences in the spectra of waveform signals between each tested breast cancer molecular subtype. It is anticipated that this technique would provide an efficient and cost-effective method for differentiating between different molecular subtypes of breast cancer.
Macrophage polarization by necrotic and apoptotic cancer cells
Kurt Williams, Brigham Young University Life Sciences Macrophages play an important role in innate and adaptive immune responses, inflammation, and tissue repair and are characterized by two distinct phenotypes: classically-activated (M1) and alternatively-activated (M2) macrophages. M1 macrophages are characterized by a pro-inflammatory phenotype and are involved in production of pro-inflammatory cytokines and aggressive engulfment, whereas M2 macrophages are characterized by an anti-inflammatory phenotype and are involved in production of anti-inflammatory cytokines (e.g. IL-10) and tissue repair. Macrophage engulfment of apoptotic cells leads to polarization toward the M2 phenotype and is thus “immunologically silent”. Additionally, there is evidence that tumor-associated macrophages (TAMs) tend toward an M2 phenotype and as a result offer protection from an immune response in the tumor microenvironment. To further investigate the role of necrotic and apoptotic cells in regulating macrophage polarization, we cultured human macrophages with necrotic, apoptotic, or standard viable Raji cells and fluorescent beads and performed an engulfment assay. In a preliminary study we found that macrophages cultured with apoptotic cells showed a decrease in engulfment levels compared to macrophages cultured with necrotic cells. Macrophages cultured with standard viable Raji cells had the lowest levels of engulfment compared to macrophages cultured with apoptotic cells or necrotic cells. Thus, in our initial experiments macrophages cultured with necrotic cells appear to have a more “M1” phenotype, whereas macrophages cultured with apoptotic cells appear to have a more “M2” phenotype. Further experiments are necessary to validate this preliminary data and further characterize the capabilities of necrotic and apoptotic cells to differentially polarize macrophages. If these observations are replicated, it has potential applications in cancer biology and therapeutics, atherosclerosis, diabetes, autoimmunity, and other diseases with an inflammatory component.
Cortisol Patterns Used as Bio-markers of Extreme Temperaments
Claudia Gonzalez, Brigham Young University Life Sciences Cortisol has been shown to be a potential bio-marker as it discriminates between individuals with and without depression (Rush et al., 1996 and Ising et al., 2007). However, cortisol has not been used to predict variation in temperament extremes that lead to pathological behaviors in adulthood. In order to examine the relationship between cortisol and temperament extremes, data from the bio-behavioral assessment (BBA) was used. The BBA data base includes data collected from over 2,700 infant rhesus macaques located in California National Primate Research Center (CNPRC). During the BBA four blood samples per subject are obtained and later assayed for plasma cortisol levels. In this study, the plasma cortisol response levels were looked at in a holistic form encompassing all individual cortisol samples. The four points of plasma cortisol concentrations were used to extract patterns of response per subject which provided classifications for each of the monkeys. The pathological patterns of cortisol response were characterized by abnormal plasma cortisol levels in response to Dexamethasone suppression testing and adrenocorticotropin ACTH injections. The variability in plasma cortisol patterns was then compared to BBA temperament ratings of vigilance, gentle, nervousness and confidence. These results showed that 12 of the 26 possible patterns of response were significantly (p<.05) related to each of the temperament ratings of vigilance, gentleness and confidence. Thus cortisol response patterns can be used both as biomarkers for vigilance, gentleness and confidence, and as potential predictors for pathological behaviors in adulthood.
Design and Synthesis of (E)-2, 4-bis(p-hydroxyphenyl)-2-butenal analogues as IKKb Inhibitors
Benjamin Gann, Utah Valley University Life Sciences (E)-2,4-bis(p-hydroxyphenyl)-2-butenal (2-Butenal) was shown to inhibit various inflammatory responses by inhibiting NF-kB pathway. A pull-down assay proved 2-butenal to bind to IKKb and was proposed as an active site kinase inhibitor through molecular docking experiment. However, 2-butanal has a highly conjugated aldehyde group that makes it very unstable. Therefore, we have designed more stable 2-butenal analogues and prepared them using Heck reaction. Molecular docking experiment shows that many of them have a greater affinity to IKKb.
Phylogeny of Heptageniidae Through Molecular Analysis
Jeffrey Leavitt, Utah Valley University Life Sciences Central Research Question: Heptageniidae is a large family within the order Ephemeroptera (mayflies). This family consists of over 500 described species. Recently a study was done across 200 of the species to break them up into subfamilies, and genera. The studied concluded that there are 29 genera and three subfamilies Ecdyonurinae, Heptageniinae, and Rhithrogeninae (Wang, 2004). Furthermore, Ogden et al. (2009) proposed that the families Arthropleidae and Pseudironidae were derived heptageniid lineages. The phylogenetic relationships of Heptageniidae, Arthropleidae, Pseudironidae, to other closely related families are inconclusive. We propose to study these three families and the three subfamilies of Heptageniidae in detail via molecular systematics.
Periphyton as an Indicator of Urban Stream Health
Clair Bidez, Westminster College Life Sciences Changes to stream ecosystems due to urbanization are known to degrade riparian ecosystems through multiple stressors including increased erosion and sedimentation, expansion of impervious surface leading to altered flow regimes, degradation of riparian vegetation and habitat, and nutrient contamination. Ultimately, such degradation can inhibit ecosystem services such as contaminant filtration and nutrient cycling. This study examined the effects of urbanization on the function of riparian communities in three streams in the Salt Lake Valley watershed. We attempted to characterize these changes through monthly monitoring in urban and non-urban reaches of the same streams. Specifically, we measured periphyton biomass (as measured by chlorophyll-a) as a known indicator of nutrient pollution and a proxy of riparian health. In addition, we monitored water quality parameters including temperature, dissolved oxygen, and dissolved nitrate concentration. The urban reaches of the streams contained 3.6 to 9.3 times the dissolved nitrate concentration as their non-urban counterparts. Mean stream periphyton biomass was positively correlated with mean stream nitrate concentration for each reach. These findings point to urbanization as a potential source of ecosystem degradation in the Salt Lake Valley. They suggest that long-term monitoring is warranted, along with an in-depth investigation into the ultimate mechanisms responsible for the degradation.
Comparing the homing ability of siblings in the species Columba livia
Eric Middleton, University of Utah Life Sciences One of the most impressive examples of homing among birds is demonstrated by Columba livia, or the rock pigeon. In racing or carrier breeds, birds can routinely travel over 100 miles and reliably find their way back to their home loft (Pratt, 1954). Bred from feral rock pigeons, these racers and carriers have been selected for their increased ability to home. While much research has been conducted on the mechanisms of homing, the heritability of homing is not very well understood. Furthermore, it is unclear if homing is predominantly learned or innate (Melhorn, Haastert, Rehkamper, 2010). The existence of homing breeds demonstrates that homing is heritable, but the degree to which this is the case or what traits in particular are improved with selective breeding are more uncertain. To attempt to better understand the heritability of homing, we will compare the homing ability of pigeons who are siblings to each other, and to unrelated pigeons. We first captured 90 wild pigeons from areas around Salt Lake City and allowed them to breed freely. We tracked the ancestry of all of the pigeons born from the feral birds and banded each of the birds in order to reliably distinguish which birds were related. We are now in the process of teaching the captive bred birds to home. Once this is completed, we will release the birds at varying distances from the loft. To quantify homing ability, we will measure angle of displacement from the loft when the birds first orient themselves and being homing, the time it takes to home, and which birds successfully make it home to the loft. This data will then be used to compare the homing ability of siblings to unrelated pigeons.
MicroScribe 3D digitizing of quadriceps tendon and calcaneal tendon with staining technique
Michael Gillespie, Brigham Young University Life Sciences It is vital to understand the anatomical microstructure of tendons and ligaments in order to ascertain their specific qualities and functions. Recent developments in micro-scribe 3D digitization are highly effective in revealing these intricacies. A necessary component to creating 3D fiber maps from this technology is the ability to distinguish between individual tissue fibers with the naked eye. However, this is a very difficult task with most tendons and ligaments. We developed a paste made of blue dye and powdered sugar that when applied, fits in-between these fibers and contrasts the specimen color. This exposes the fine architecture, making individual fibers much more visible and thus able to be 3D digitized. With these 3D fiber maps now available, tendon and ligament microstructure can be viewed in greater detail than previously possible. This technique was applied to human cadaveric calcaneal tendon and quadriceps tendon. It was discovered that the fibers of human calcaneal tendon have higher overlap relative to the rigidly parallel fibers of the quadriceps tendon. This further understanding carries implications regarding the advancement of biomechanical models, artificial reconstruction, and surgical repair of these tissues. It also highlights the need for further investigation into the microstructure differences among tendons and ligaments.
3D Mapping of Cardiac Nerves for Improved Cardiac Ablation Procedures in the Treatment of Cardiac Arrhythmia
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.
The Role of Endocannabinoid Receptor GPR55 on Learning and Memory
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.
High-frequency ultrasound of breast tissue phantoms with histology-mimicking microstructures
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.
Seasonal Water Availability and Temperature Drive Subalpine Carbon Soil Flux
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.
High-frequency ultrasound study of excised tissue cryopreserved via simple sugars
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.
The function of β-catenin in the maintenance of multipotent pancreatic progenitors
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.
Discovering Dermapteran Relations: Phylogeny of earwigs based on molecular evidence
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?
Engineering a Pathogen Specific Single Chain T-Cell Receptor Specific for Listeria monocytogenes.
John Hancock, Brigham Young University Life Sciences LLO56 and LLO118 are CD4+ T cells specific for the same Listeria monocytogenes epitope. Despite their TCRs differing by only 15 amino acids, LLO118 and LLO56 have dramatically different primary and secondary responses to Listeria monocytogenes infection. We reasoned that LLO56, the single chain TCR (Vβ2-linker-Vα2) could be subjected to directed evolution to generate mutants that are more stable and bind to peptide-MHC with higher affinity. Single chain LLO56 was fused to the yeast surface protein Aga-2 and error prone PCR was used to generate mutagenic libraries. A first generation stabilized single chain TCR (scTCR) was selected using biotinylated Vβ2 and Vα2 antibodies and anti-biotin beads. The first generation LLO56 mutant expressed LLO56 on the surface of yeast at higher levels than wild type by flow cytometry. To produce mutants with additional stability, a second-generation mutant was generated by combining multiple stability mutations isolated in a number of first generation clones.
Engineering a stabilized Single Chain T-Cell Receptor called LLO118 for use in generating high affinity T cell receptors.
Brian Ballard, Brigham Young University Life Sciences Antigen presenting cells digest and display proteins from foreign and infected cells on the major histocompatibility complex (MHC) which can then be recognized by T-cells through their T cell receptor (TCR). LLO56 and LLO118 are CD4+ T cells specific for the same Listeria monocytogenes epitope but show dramatically different primary and secondary responses to infection. Because TCRs have very low affinity for MHC we would like to create a high affinity T cell. We reasoned that the single chain LLO118 TCR (Vβ2-linker-Vα2) could be subjected to directed evolution to generate mutants that are more stable and then used as a template for engineering high affinity T cell receptors. Single chain LLO118 was fused to the yeast surface protein Aga-2 and error prone PCR was used to generate mutagenic libraries. The first generation stabilized LLO118 single chain TCR (scTCR) was selected using biotinylated Vβ2 and Vα2 antibodies and anti-biotin beads and it expressed LLO118 at higher levels than wild type by flow cytometry. To produce mutants with additional stability, a second mutagenic library using the first generation mutants as templates has been produced and the most stable clones will be selected after temperature denaturation, permitting isolation of clones with increased stability for generating high affinity pathogen specific scTCRs. After engineering a high affinity T cell our research will further understanding on TCRs and the MHC and could also serve as a resource for creating a therapeutic drug.
Coronary vascular function is improved in ischemic patients following continuous-flow left ventricular assist device implantation
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.
Genetic Origins of Mercury Resistance in Great Salt Lake Halophiles
Ashtyn Smith, Westminster College Life Sciences Methylmercury (CH3Hg) is a neurotoxin that accumulates in lakes and streams due to the action of microorganisms, which can produce this biologically relevant organic form from elemental mercury (Hg). Therefore, the activities of microorganisms become key to understanding the balance of Hg and CH3Hg in the movement through the food chain in any ecosystem. Many species of microorganisms are resistant to Hg and can thrive in polluted waters. Recent studies have shown that Hg resistance in microbes can stem from one of two gene pairs, merAB or hgcAB. The merAB system allows the organism to covert CH3Hg into elemental Hg. Conversely, the hgcAB system coverts Hg into CH3Hg. Thus, it is important to determine how the microbial community of Great Salt Lake, Utah is affecting the CH3Hg concentrations in the lake. In order to determine the genotype of the lake’s halophiles, “salt-loving” organisms, microorganisms were collected from the deep brine layer in eight areas of the lake. The microorganisms were then isolated and cultivated on increasing concentrations of HgCl2. Halophiles from these samples have been isolated on 25 ppm HgCl2 at various salinities, demonstrating a robust resistance to Hg. PCR amplification and genetic sequencing will be used to determine the gene mechanism of mercury resistance (merAB or hgcAB) as well as the 16S rRNA gene, which will aid in identification of the species. Should this study identify GSL microorganisms that exhibit the merAB genotype, these organisms could potentially be utilized as bioremediators of the CH3Hg pollution in the lake.
Tissue Engineered Vascular Graft for Surgical Implantation
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.
Predation Shapes Personalities in Brachyraphus Fishes
David Money, Brigham Young University Life Sciences Interest in animal personalities, and particularly the effect that different environments have on personality, has increased dramatically over the past decade. Understanding how individuals vary in their behavior, and if there are consistent differences among populations from divergent selective environments, lays the foundation for studies focusing on the contribution of divergent behavior in species formation. To date, studies that have focused on how personalities differ across ontogenetic stages have failed to compare populations that occur in dramatically different environments. Our study attempts to fill this void by studying the ontogeny of personality in populations that have evolved in environments with different levels of risk (i.e., predation vs. no-predation). We tested the expression of different personality traits evolution across ontogeny (i.e., from juveniles to full grown adults) in two sister species of live-bearing tropical fish, Brachyraphis roseni and B. terrabensis. These species have evolved in different selective environments, with B. roseni having evolved in an environment where predators were present, while B. terrabensis evolved in an environment lacking predators. We assessed the boldness expression of individuals from several groups in populations, namely juveniles, small adults, and large adults. To measure boldness, we used an emergence test, and also an exploration and activity test (i.e., ratio of movement to idleness during an allotted time period). Our study provides evidence for an important relationship between predation environment and the evolution of personality traits across ontogeny.
Prevention and Disruption of Bacterial Biofilms
Aimee Newsham, Dixie State University Life Sciences Millions of people are infected yearly with resistant pathogens, including MRSA (methicillin-resistant Staphylococcus aureus), a biofilm-forming pathogen that is often transferred to patients from contaminated surfaces. Therefore, improved methods to destroy biofilm-encapsulated pathogens or to prevent their initial formation are required. This research is focused on the development of a safe treatment against biofilms by integrating organic salts, or ionic liquids (ILs), into different surfaces. Textiles were integrated with ILs to prevent formation of biofilms/bacterial growth, and were also treated post-exposure to determine if the biofilms could be destroyed post-contamination. Effectiveness of newly designed ILs were tested via inhibition zone studies on LB agar plates, and post-treatment samples were analyzed via scanning electron microscopy for presence of bacteria. The bacteria tested included Pseudomonas aeruginosa, Staphylococcus epidermidis, and Escherichia coli. These microbes are similar to MRSA in that they form biofilms comprised of extracellular proteins, DNA and polysaccharides. Bacterial colonies encapsulate themselves with biofilms to provide protection from threats, including antibacterial drugs. By integrating ionic liquids into textiles, formation can be prevented by IL solvation and sequestering of the extracellular biofilm components, including the proteins and DNA. This research could have tremendous implications regarding defeating bacteria that are resistant to existing treatments due to biofilm encapsulation. Additionally, the results could lead to new antimicrobial textiles and new approaches to prevent adherence and growth resistant biofilm-encapsulated pathogens.