Winners of Paper Presentations for 2012

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Paper Presentations

SESSION 1: CELLULAR AND DEVELOPMENTAL

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Wasson, Cassandra, and Troy Skwor. Theta Omega, Gannon University. Effect of photobiomodulation (405nm and 670nm) on Chlamydia trachomatis growth and inflammatory response of cervical epithelial cells.

Chlamydia trachomatis , an obligate intracellular bacterium, is the leading cause of preventable blindness and bacterial sexually transmitted diseases worldwide. The majority of reproductive infections are asymptomatic and failure to identify and properly treat could lead to sequelae, including pelvic inflammatory disease, salpingitis, and ectopic pregnancies in females and epididymitis and infertility in males. Red light therapy (670nm) has been associated with tissue healing, inflammation reduction, and pain reduction. Additionally, violet light (405nm) restricts the growth of various bacterial pathogens. Because recent studies indicate an increase in recurrence of chlamydial infections post antibiotic treatment, particularly infections of the eye, alternative treatments are necessary. Our objective was to assess photobiomodulation as possible alternative treatments for C. trachomatis infections. Human cervical epithelial cells, HeLa, were infected with C. trachomatis serovar E and treated with 405 nm irradiation using light-emitting diodes at various energy densities. Bacterial growth was assessed by analyzing the ratio of bacterial housekeeping gene (16S) to host housekeeping gene (GAPDH). Supernatants were also collected and assessed for the proinflammatory protein, IL-6. Our results demonstrated decreased bacterial growth and IL-

6 production upon 405 nm irradiation. These findings suggest further medicinal applications of photobiomodulation as possible alternative treatment options for C. trachomatis infections.

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Ilacqua, April, and Dr. Kyle McQuade. Epsilon Omicron, Colorado Mesa University.

Investigation into the Mechanism by which Green Tea Catechins affect Dictyostelium

Development.

Green tea has been suggested to promote health via the catechin epigallocatechin gallate

(EGCG). This compound has received much research interest as a potential therapeutic and protective agent, but the mechanism by which it acts is not clear. The amoeba

Dictyostelium discoideum is a model organism that is being used to characterize the activities of potential pharmaceuticals. In the Dictyostelium life cycle unicellular amoeba aggregate together and develop to form multicellular fruiting bodies, usually within 24 hours. The mechanisms required for these events (cellular motility, chemotaxis, phagocytosis, signal transduction, and cellular differentiation) have been studied extensively and require signaling events similar to that seen in vertebrates. This suggests that the amoeba is a useful system in which to characterize the effects of drugs intended for human use. We have shown that the green tea catechin EGCG blocks the

Dictyostelium life cycle. EGCG is not toxic, blocks development, and the interruption in the life cycle may be blocked due to inhibition of signaling pathways required for cellular transition to differentiation and development. These data suggest that Dictyostelium is a useful model to characterize the activities of catechins and other natural products.

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Olson, Amalia E. Gamma Omega, Bethel University. The Contractile Effects of Red

Raspberry Leaf ( Rubus idaeus ) Extract on Mus musculus Uterine Tissue in vitro .

An increasing percent of the population today is using herbal alternatives for their healthcare needs without knowledge on the efficacy and side effects of many of these compounds. The purpose of this research was to collect data that either supported or refuted claims that red raspberry leaf Rubus idaeus induces labor and/or promotes uterine tone. Red raspberry leaf (RRL) extract (1.5 mg - 50 mg/ 1 mL dH20) was applied to isolated mice uterine tissues and induced a contractile response. Responses however, were not dose dependent (g tension, P = 0.33). When the responses were standardized as a percent of their acetylcholine 10

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M response, the increases were significant (P =

0.005). Receptor antagonism was used in an effort to determine possible mechanisms of action. Both cholinergic muscarinic receptor blockers (atropine, scopolamine) and nicotinic receptor blockers (tubocurarine, hexamethonium) failed to block RRL induced contractions, indicating that the RRL constituents do not work through parasympathomimetic pathways. Atosiban, an oxytocin antagonist, also did not inhibit

RRL activity. Results herein do show that at the level of isolated uterine tissues, RRL extracts do induce contraction. This may lend support for the claims that RRL can be used as an oxytocic agent.

SESSION 2: ECOLOGY

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Coe, Lauren. Xi Omega, Siena Heights University. Oviposition and Larval Performance of Pieris Rapae with regards to Color Mutants of Brassica Rapa .

Pieris rapae, or better known as the cabbage white butterfly, is an invader species which causes great damage to Brassica rapa plants and crops. Intraspecific host plant selection was studied by allowing naïve cabbage white butterflies to land on freely accessible or enclosed green, variegated and yellow Brassica plants. Female cabbage white butterflies preferred to land on green and variegated Brassica plants. No significant difference in first landing choice was found between the freely accessible and enclosed Brassica plants. It can be deduced that female cabbage white butterflies do not use olfactory cues but rely on visual cues when selecting one host plant over another.

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Frei, Katelynn J. and Robert C. Dowler. Epsilon Sigma, Angelo State University.

Patterns Of Habitat Use And Competition Between Nine-Banded Armadillos ( Dasypus novemcinctus ) And Hog-Nosed Skunks ( Conepatus leuconotus ).

Nasal nematodes of the genus Skrjabingylus are known to infect the frontal sinuses in the crania of skunk species of North America. A total of 324 skulls of striped skunks

( Mephitis mephitis ) either in museum collections or obtained from the rabies lab at the

Texas Department of Health Services were examined for obvious lesions from

Skrjabingylus chitwoodorum . We documented the age of these individuals by looking at three sets of cranial sutures and assessed the degree of cranial damage caused by this nematode. Forty-one percent of skulls showed evidence of Skrjabingylus infection. For those skulls for which data were available on gender, we found no significant difference in the frequency of infestation between males and females. Older age classes showed significantly more cranial lesions than younger ones, likely as a result of increased chance of acquisition of the parasite over the host’s life time. Previous studies have shown a pattern of Skrjabingylus infections where higher incidence occurs in moist regions and lower incidence in arid areas. Continuing studies to expand sample size and areas of Texas will determine if Skrjabingylus incidence varies geographically according to these climatic factors.

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Duell, Meghan, T. Apted, N. Hall, L. Bates-Albers, L. Pendergraft, E. Zuniga, A. Sorucu,

D. Ikizoğlu, S. Semilova, C.I. Abramson, L. Aydin, J.F. Barthell, I. Çakmak, H.H. Oruç,

H. Wells, and J.M. Hranitz. Rho Chi, Bloomsburg University. Honeybee Stress:

Behavioral & Physiological Implications of Flumethrin Treatment.

With honeybee populations in decline, an understanding of the effects ofenvironmental stressors, especially agrochemicals, is paramount. A hormesis model approach was used in this study to illustrate possible stimulatory, inhibitory, and lethal effects of flumethrin.

Anatolian honeybees ( Apis mellifera anatoliaca ) were collected at Uludağ University

Beekeeping and Development Center in Bursa, Turkey. In Experiment 1, bees were given

0.125-4.00

 g/bee doses of 50% sucrose Akarvil ® 7.5% flumethrin solution. At 24hrs, the overall LD

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was 0.527ug/bee with 95% confidence (CI = 0.85, 1.26; Wald χ

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45.48, P < 0.0001). Mortality was observed earlier at higher doses (p<0.001, X 2 = 48.166 for .25ug/bee vs. 0.5-4.ug/bee). In Experiment 2, bees were restrained, given 0.0625-

2.00

 g/bee, and assessed via behavioral assay. Brain HSP70 content was determined.

Subjects displayed severe physical and behavioral symptoms (loss of directed movement in legs, antennae, body, and wings, loss of proboscis extension reflex, local or systemic paralysis, vomiting, and convulsions). The behavioral LC

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for motor function was 0.27

μg/bee (95% confidence, CI = 0.16, 0.41). Profound symptoms and low lethal concentration indicate that doses were too high to completely illustrate a hormetic reaction. Flumethrin (as Akarvil ®) was highly toxic to honeybees.

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Everman, Elizabeth . Lambda, William Jewell College. An investigation of genetic structure and dispersal patterns of Eleutherodactylus coqui on Hawai’i Island.

The frog Eleutherodactylus coqui was introduced to the Hawai’ian archipelago in the late

1980s, and became established as a wide-spread, high profile invasive species on Hawai’i

Island. Population establishment occurred over a ten-year time period when the majority of governmental attempts to eradicate the frog were taking place. The continued spread of the coqui during this time indicates that humans are playing an important role in facilitating coqui dispersal; however, it is not known whether this facilitation is active

(intentional) or passive (unintentional). Microsatellite markers were used to identify the dispersal pattern using genotype data collected from 489 coqui frogs collected from 25 populations on Hawai’i Island. A Mantel Test was used to assess the correlation between genetic and geographic distance. If coqui populations were established under diffusion dispersal, this correlation is expected to be positive, while lack of or a negative correlation would indicate that population establishment has occurred through jump dispersal. Analysis of five microsatellites indicates that genetic distance is not correlated with geographic distance and suggests that humans are playing an important role as facilitators of coqui dispersal. A phylogenetic analysis of genetic distance illustrates several populations that are driving this relationship. Together, these analyses support the hypothesis that humans are playing an important role in coqui dispersal.

SESSION 3: MICROBIOLOGY

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St.Jacques, Brittany, and Ashley Moye. Kappa Epsilon, Old Dominion University.

Developing a Novel Quantitative PCR Diagnostic for the Detection of Mycobacterium marinum .

Mycobacterium marinum causes severe disease in poikilothermic animals and is a zoonotic pathogen of humans. M. marinum has a cosmopolitan distribution and is of local concern in the Chesapeake Bay as a pathogen of striped bass ( Morone saxatilis ). Despite the importance of M. marinum as a veterinary and human pathogen, molecular methods for quantitation of this bacterium have not yet been developed. The goal of this study was to develop a quantitative PCR diagnostic assay specific to M. marinum. The small subunit ribosomal RNA (16S rRNA) gene is a commonly used target for PCR assays.

However, 16S rRNA gene sequences are highly conserved in Mycobacterium spp., making differentiation problematic. Insertion sequences (bacterial transposable elements) were used as alternative targets in this work. Specificity, sensitivity, and inhibition by background DNA testing were conducted for insertion sequences MYMA01 and

MYMA06. High species-specificity, and in some cases strain-specificity, was demonstrated. The qPCR assays, based on insertion sequences MYMA01 and

MYMA06, represent the first M. marinum specific quantitative PCR diagnostics to date.

The assays will be useful for detecting M. marinum in environmental samples and diagnosing infections in poikilothermic animals and humans. The assays serve as rapid, economical alternatives to traditional culture-based methods without the complications associated with culturing tissue and water samples.

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Shelley, Virginia. Mu Iota, Northern Kentucky University. Inhibition of White Nose

Syndrome in Hibernating Bat Colonies: Identification of Anti Fungal Compounds.

Since it first appeared in 2006, White-Nose Syndrome (WNS), caused by the fungus

Geomyces destructans , has been devastating bat populations in the US. Killing more than

2,000,000 bats since it was first discovered, WNS has affected more than 115 cave hibernacula. To reduce the spread of this pathogen and protect endangered bat species, we have focused on testing natural organic compounds that are able to prevent the growth and further transmittance of G. destructans . To do this, various compounds were tested on their ability to prevent the growth of the model organism Geomyces pannorum using two different competition assays: 1) a disk diffusion assay; 2) a direct application of the chemical solution; and 3) shoe assays to develop a decontamination protocol for tourists at Mammoth Cave National Park. In order to specifically target the Geomyces species, the same tests were also performed using Penicillium pinophiolium and Aspergillus brasiliensis . This ensured that if any chemical was successful in the prevention of growth of G. pannorum , it did not destroy other fungal populations also living within the cave.

A number of compounds have been identified for further testing, both on the pathogen G. destructans and on healthy bat populations.

SESSION 4: MOLECULAR BIOLOGY

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Graham, Melanie, LaKesha Seals, Tanner Wheeler, Maggie Yoder, Carissa Fisher,

Ariana Eakle, and Andrea Holgado. Delta Sigma, Southwestern Oklahoma State

University. Synaptic connections are regulated via VSM-1, a SNARE interacting protein.

Membrane fusion in eukaryotes is mediated by SNARE complex formation. VSM-1, a

SNARE interacting protein regulator, prevents the formation of SNARE complexes and inhibits fusion. Work reported by Gerst and collaborators have shown that yeast syntaxin and synaptobrevin bind to VSM-1 in a phosphorylation dependent manner. This process resulted in the inhibition of exocytosis at the vesicular priming step. To expand our knowledge on the mediation of intracellular membrane trafficking underlying synapse formation, we began characterizing the functional role of VSM-1 in the genetic model organism C. elegans . First, we determined that endogenous VSM-1 is expressed in nematodes and enriched at synapses. Second, using diverse assays the phenotype of a vsm-1 mutant isolated by the Oklahoma Genome Consortium was characterized. For instance, pharmacological assays showed that vsm-1 mutants have an enhanced

sensitivity to “Aldicarb,” a cholinesterase inhibitor. This phenotype can be interpreted as a consequence of increased neurotransmitter release in the mutant background and/or greater synaptic connectivity. Third, immunostaining analysis focusing on neuromuscular junctions showed that mutants lacking a normal VSM-1 protein have a greater density of synaptic varicosities when compared to wild-type nematodes. Lastly, analysis of associative learning and memory demonstrate that vsm-1 mutants developed enhanced short and long-term memory.

In summary, our studies show that C.elegans

VSM-1 is enriched at neuromuscular junctions and seems to regulate synaptic signaling by promoting synapse formation.

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Niazi, Mo (Mohammad). Omicron Phi, Southern Nazarene University. The

Experimental Determination of the Effect of Plant Sterols on Cholesterol Esterase.

Plasma cholesterol levels have been lowered by 10% through dietary manipulation involving plant steryl esters. This reduction results from inhibiting cholesterol absorption, which is believed to require the cleavage of dietary cholesteryl esters by cholesterol esterase. The basic steryl structural parameters required by cholesterol esterase are not well understood. This study utilizes chromophoric steryl furylacrylate esters which have similar structural properties to plant sterols. The hydrolysis of the chromophoric esters by cholesterol esterase was followed spectrophotometrically. We found that removing the double bond located on the B ring of the sterol moiety between

C-5 and C-6 increased the half-life by greater than a factor of 4 at 37°C, pH 7.50, when compared to cholesteryl furylacrylate. It was also found that placing a double bond in the hydrophobic tail of the steryl (between C-22 and C-23), decreased the hydrolytic half-life from 2.0 min to 1.3 min at 37°C, pH 7.50, when compared to cholesteryl furylacrylate.

These studies provide insight into the substrate structural parameters of cholesterol esterase, which in turn may lead to rational development of therapeutic treatments for lowering plasma cholesterol levels.

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Mason, Mary A., and Michael C. Hanna. Delta Gamma, Texas A&M

University/Commerce. Possible protein interaction between maspardin and ALDH18A1 in Mast syndrome.

Hereditary Spastic Paraplegias (HSPs) are a family of neurological disorders characterized by weakness and spasticity of the lower limbs and sensory impairment.

Mast syndrome is a complicated, autosomal recessive form of HSP exhibiting symptoms of dementia, thinning of the corpus callosum, white matter abnormalities, and spastic paraperesis. Patients with Mast syndrome carry a mutation along their SPG21 gene producing a premature stop codon. Thus, Mast syndrome is likely due to loss of functional maspardin protein. Previous studies demonstrate maspardin interacts with

ALDH16A1 and following maspardin deletion aldehyde dehydrogenase ALDH18A1,

another member of the ALDH superfamily, was upregulation 1.66 fold suggesting an interaction between ALDH18A1 and maspardin may occur. Patients with a missense mutation, R84Q, exhibit progressive neurodegeneration and bilateral subcapsular cataracts. In recent studies, variants of ALDH18A1 were found to be significantly associated with dementia with Alzheimer’s Disease in Down syndrome patients suggesting a link between ALDH18A1 and other neurodegeneration diseases.

Interestingly, a new HSP has been found to be caused by a mutation within the

ALDH18A1 gene and is being investigated. In vitro and in vivo immunoprecipitation analyses suggest an interaction occurs, whether this is interaction is direct or indirect will be determined as well as the interaction domains.

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Gruder, Olivia K., Crystal D Pickeral, and Brian Spetman. Sigma Tau, Florida State

University. Histone Deacetylase Inhibitors Regulate Nucleosome Distribution During the Innate

Immune Response.

Eukaryotic genomes are organized into chromatin. The structure of chromatin plays a critical role in the regulation of the human genome. An understanding of the role of chromatin structure and its relationship to gene regulation is critical to developing new strategies to prevent and treat diseases. Histone deacetylase inhibitors (HDI) alter chromatin structure by preventing the removal of acetyl groups from chromatin. HDI have been prescribed for the past 40 years as anticancer, antipsychotic and antiinflammatory drugs. However, the mechanism by which they function has not been fully uncovered. We chose to investigate the anti-inflammatory action of this class of drug in the context of an innate immune response. We treated a human macrophage cell line with two different HDI. We then followed HDI treatment with an immune insult that mimicked bacterial, viral or fungal infection. We hypothesized that HDI would affect the genomic response to inflammatory stimuli by regulating chromatin structure. We measured chromatin structure at approximately 500 of genes involved in the innate immune response using an innovative microarray technology. We found that the antiinflammatory effect of HDI may lie in their ability to prevent the necessary chromatin structural changes associated with the immune response. Furthermore, we are able to classify subsets of genes by their response to the HDI. These subsets include chromatin structural changes unique to the insult, as well as chromatin structural changes unique to treatment with HDI. These experiments mark an important step in understanding HDI mechanism and role of chromatin structure in genome response.

This work was supported by an Honors Scholarship Travel Award from FSU.

SESSION 5: ORGANISMAL

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Nguyen, Austin, Ellie Altomarem, and Catharine McElwain. Epsilon Delta, Loyola

Marymount University. Cadmium Accumulation and Resistance in Drosophila melanogaster .

The fruit fly, Drosophila melanogaster, demonstrates sensitivity to heavy metal exposure that is both variable and selectable. Our lab has demonstrated significant differences in survival of wild-type D. melanogaster raised on varied concentrations of Cadmiumenriched food and has measured cadmium levels in treated flies using mass spectrometry.

Preliminary data from flies across eight generations of exposure indicate that descendants of flies that survived exposure to high levels of cadmium are more likely to survive high exposures, meaning that resistance is selectable. Furthermore, cadmium levels, quantified by mass spectrometry, may decline in exposed flies selected for resistance compared to sensitive flies exposed to the same concentrations of cadmium. This decrease in cadmium content may indicate a metabolic mechanism of resistance, rather than the literaturesuggested sequestration mechanism. The ability of flies to develop resistance to heavy metals may have significant impact on food webs in contaminated environments and may also indicate levels of exposure to higher trophic levels. The local Ballona wetlands are contaminated with heavy metals, particularly cadmium, lead, and copper, of which the levels in flies we have begun to investigate. Interestingly, we may have also observed an influence on copper levels in flies selected for cadmium resistance, which will be an area of further investigation.

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Blank, Noelle A., and Greg Andraso. Theta Omega, Gannon University. Comparison of diet and pharyngeal apparatus of round gobies ( Neogobius melanostomus ) from two populations in Erie County, Pennsylvania.

Round gobies ( Neogobius melanostomus ) shift their diet from arthropods to dreissenid mussels as they grow, and this diet shift is correlated with developmental changes in pharyngeal structures. Changes in the pharyngeal apparatus may cause gobies to switch from arthropod to dreissenid prey. Alternatively, the dietary switch may drive pharyngeal remodeling. To test the possibility of phenotypic plasticity (i.e. that diet influences pharyngeal morphology), we compared prey availability, food habits, and pharyngeal morphology of round gobies from two populations: Presque Isle shipping channel (“dreissenid-rich” location) and Fairview gravel pit (“dreissenid-absent” location). If the pharyngeals are phenotypically plastic, we would expect to see less robust structures and the maintenance of narrow (< 0.3 mm) teeth in round gobies from the gravel pit, compared to those from the shipping channel. We have found that dreissenids are abundant in the shipping channel and compose nearly the entire diet of round gobies collected there. In contrast, dreissenids appear to be absent in the gravel pit.

Round gobies collected from that site contain a variety of arthropods, but also contain small gastropod mollusks. Analyses of the pharyngeals of fish from the two sites suggest differences in morphology that are consistent with phenotypic plasticity.

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Clippinger, Amy K. Mu Iota, Northern Kentucky University. Which neurodegenerative disease is it? Characterizing Atp13a2 deficient mice.

An animal model for Kufor-Rakeb syndrome, an atypical form of Parkinson's disease

(PD), and neuronal ceroid lipofuscinoses (NCL), a lysosomal storage disorder, has been generated by knocking out the Atp13a2 gene in mice. Atp13a2 encodes a lysosomal Ptype transport ATPase that is thought to be necessary for normal lysosomal function, including protein degradation and autophagy. Pathway specific arrays were used to assess the expression of autophagy-related genes in mouse embryonic fibroblasts and brain regions isolated from Atp13a2 knockout mice to determine if autophagic processes were perturbed. We also postulated that Atp13a2 deficient mice would be more prone to neurodegenerative diseases such as Alzheimer's, in which protein aggregates have been shown to contribute to neuronal dysfunction and cognitive impairment. To test this hypothesis we introduced a gene into Atp13a2 deficient mice that is associated with familial Alzheimer's disease, the human mutant amyloid precursor protein gene (APP).

Mice were tested in the Morris water maze spatial memory task at 6, 9 and 12 months.

Brains were analyzed for the presence of protein aggregation, and evidence of the accumulation of aging pigment, or lipofuscin, in knockout brains. Our results suggest that

Atp13a2 deficient mice might serve as a model for neuronal ceroid lipofuscinoses.

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