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An Exploration Of Pharmacognosy And Its Potential In The Multi-Faceted Solution Required To Address Hiv/Aids In Sub-Saharan Africa, Alexandra Sassi

Pell Scholars and Senior Theses

This work has both both biological and anthropoligcal foci. It addresses research done on the medicinal properties of plants and how this research could make positive contributions to the current social and biological issues surrounding the HIV/AIDS epidemic in sub-Saharan Africa.

Selex-Based Identification Of Synthetic Binding Sites For Streptomyces Acidiscabies 84.104 Γ-Butyrolactone Receptors: Sabs And Sabr., Caitin Nicole Spaulding

Biology Honors Theses

Bacteria belonging to the Gram positive genus Streptomyces produce many secondary metabolite natural products of pharmaceutical importance and undergo a complex program of morphological differentiation. The expression of genes involved in these processes is often regulated by γ-butyrolactone (GBL) interactions with cognate GBL receptors. GBL receptors regulate gene expression by binding specific AT-rich DNA sequences known as autoregulatory elements (ARE) in response to available intracellular GBL pools. We previously identified two S. acidiscabies GBL receptor genes, sabR and sabS, flanking a gene encoding a GBL synthase homolog sabA. Genetic and biochemical studies revealed that sabR negatively regulates sabS expression by …

Fracture In Teeth—A Diagnostic For Inferring Bite Force And Tooth Function, Paul J. Constantino, Brian R. Lawn, James J.-W. Lee, Peter W. Lucas

Biological Sciences Faculty Research

Teeth are brittle and highly susceptible to cracking. We propose that observations of such cracking can be used as a diagnostic tool for predicting bite force and inferring tooth function in living and fossil mammals. Laboratory tests on model tooth structures and extracted human teeth in simulated biting identify the principal fracture modes in enamel. Examination of museum specimens reveals the presence of similar fractures in a wide range of vertebrates, suggesting that cracks extended during ingestion or mastication. The use of ‘fracture mechanics’ from materials engineering provides elegant relations for quantifying critical bite forces in terms of characteristic tooth …

A Complement Receptor C5a Antagonist Regulates Epithelial To Mesenchymal Transition And Crystallin Expression After Lens Cataract Surgery In Mice, Rinako Suetsugu-Maki, Nobuyasu Maki, Timothy P. Fox, Kenta Nakamura, Richard Cowper.Solari, Craig R. Tomlinson, Hongchang Qu, John D. Lambris, Panagiotis A. Tsonis

Biology Faculty Publications

Purpose: To evaluate the effects of complement employing a mouse model for secondary cataract. Methods: The role of complement receptor C5a (CD88) was evaluated after cataract surgery in mice. An antagonist specific to C5a receptor was administered intraperitoneally to mice. Epithelial to mesenchymal transition (EMT) was evaluated by alpha-smooth muscle actin (α-SMA) staining and proliferation by bromodeoxyuridine (5-bromo-2'- deoxyuridine, BrdU) incorporation. Gene expression patterns was examined by microarray analysis and quantitative polymerase chain reaction (QPCR). Results: We found that administration of a C5aR antagonist in C57BL/6J mice decreases EMT, as evidenced by α-SMA expression, and cell proliferation. Gene expression by …

Phosphatidic Acid Binds And Stimulates Arabidopsis Sphingosine Kinases, Xuemin Wang, Liang Guo, Girish Mishra, Kyle Taylor

Biology Department Faculty Works

Phosphatidic acid (PA) and phytosphingosine-1-phosphate (phyto-S1P) have both been identified as lipid messengers mediating plant response to abscisic acid (ABA). To determine the relationship of these messengers, we investigated the direct interaction of PA with Arabidopsis sphingosine kinases (SPHKs) that phosphorylate phytosphingosine to generate phyto-S1P. Two unique SPHK cDNAs were cloned from the annotated At4g21540 locus of Arabidopsis, and the two transcripts are differentially expressed in Arabidopsis tissues. Both SPHKs are catalytically active, phosphorylating various longchain sphingoid bases (LCBs) and are associated with the tonoplast. They both interact with PA as demonstrated by lipid-filter binding, liposome binding, and surface plasmon …

Determining The Composition Of The Dwelling Tubes Of Antarctic Pterobranchs, Lukasz J. Sewera

Honors Projects

Pterobranchs are a group of marine invertebrates within the Hemichordata, which share characteristics with both chordates and echinoderms.  Pterobranchs live in colonies of secreted tubes, coenicia, which are composed of a gelatinous material of unknown composition.  Visually, the tubes appear similar to the tunic of tunicates, a group of invertebrates within the Chordata. The nonproteinaceous tunic of tunicates is composed of cellulose, which is unusual.  The goal of this study was to determine the composition of the pterobranch coenicium. Some aspects of pterobranch phylogeny are still unclear even after multiple molecular and morphological studies.  Identification of any new shared characteristics …

Involvement Of Protein Kinase C And Protein Kinase A In The Enhancement Of L-Type Calcium Current By GabaB Receptor Activation In Neonatal Hippocampus, Jennifer Grace Bray, Michelle Mynlieff

Biological Sciences Faculty Research and Publications

In the early neonatal period activation of GABA_B receptors attenuates calcium current through N-type calcium channels while enhancing current through L-type calcium channels in rat hippocampal neurons. The attenuation of N-type calcium current has been previously demonstrated to occur through direct interactions of the βγ subunits of G_i/o G-proteins, but the signal transduction pathway for the enhancement of L-type calcium channels in mammalian neurons remains unknown. In the present study, calcium currents were elicited in acute cultures from postnatal day 6–8 rat hippocampi in the presence of various modulators of protein kinase A (PKA) and protein kinase C …

Natal Dispersal And Sociality Of Young Galapagos Hawks On Santiago Island, Jose Rivera, F. Vargas, Patricia Parker

Biology Department Faculty Works

No abstract provided.

Evaluating The Effectiveness Of Conservation Education Incorporated In An Animal Exhibit At The Indianapolis Zoo, Vanessa Snyder, Given Harper, Faculty Advisor

John Wesley Powell Student Research Conference

No abstract provided.

Determining The Composition Of The Colony Tubes Of Pterobranchs, Andrew Mcdonald, Tyler Saunders, Elizabeth Balser, Faculty Advisor, Lukasz Sewera

John Wesley Powell Student Research Conference

No abstract provided.

Episodic Radiations In The Fly Tree Of Life, Brian M. Wiegmann, Michelle D. Trautwein, Isaac S. Winkler, Norman B. Barr, Jung-Wook Kim, Christine Lambkin, Matthew Bertone, Brian Cassel, Keith Bayless, Alysha Heimberg

Dartmouth Scholarship

Flies are one of four superradiations of insects (along with beetles, wasps, and moths) that account for the majority of animal life on Earth. Diptera includes species known for their ubiquity (Musca domestica house fly), their role as pests (Anopheles gambiae malaria mosquito), and their value as model organisms across the biological sciences (Drosophila melanogaster). A resolved phylogeny for flies provides a framework for genomic, developmental, and evolutionary studies by facilitating comparisons across model organisms, yet recent research has suggested that fly relationships have been obscured by multiple episodes of rapid diversification. We provide a phylogenomic …

Eight Criticisms Not To Make About Group Selection, Omar Tonsi Eldakar, David Sloan Wilson

Biology Faculty Articles

Group selection, which was once widely rejected as a significant evolutionary force, is now accepted by all who seriously study the subject. There is still widespread confusion about group selection, however, not only among students and the general public, but among professional evolutionists who do not directly study the subject. We list eight criticisms that are frequently invoked against group selection, which can be permanently laid to rest based upon current knowledge. Experts will always find something to critique about group selection, as for any important subject, but these eight criticisms are not among them. Laying them to rest will …

Section Abstracts: Biology With Microbiology And Molecular Biology

Virginia Journal of Science

Abstracts of the Biology with Microbiology and Molecular Biology Section for the 89th Annual Meeting of the Virginia Academy of Science, May 25-27, 2011, University of Richmond, Richmond VA.

Geographic Variation In Temperature Tolerance As An Indicator Of Potential Population Responses To Climate Change, Cascade J.B. Sorte, Sierra J. Jones, Luke P. Miller

Faculty Publications, Biological Sciences

The temperature tolerances of individuals in geographically separated populations of a single species can be used as indicators of each population's potential to persist or become extinct in response to climate change. We evaluated the population-level variation in temperature tolerance in populations of several marine invertebrate taxa, including bryozoans, tunicates, bivalves, and gastropods, separated by distances of < 200 km to > 5000 km. We then combined physiological thermotolerance data with current temperature data and climate change predictions to predict which of these populations may be most vulnerable to future changes. In a trans-continental comparison of four subtidal epibenthic species, we show that populations on …

Section Abstracts: Natural History And Biodiversity

Virginia Journal of Science

Abstracts of the Natural History and Biodiversity Section for the 89th Annual Meeting of the Virginia Academy of Science, May 25-27, 2011, University of Richmond, Richmond VA.

A Unique Coxiella Burnetii Lipoprotein Involved In Metal Binding (Limb), James M. Battisti, Linda D. Hicks, Michael F. Minnick

Biological Sciences Faculty Publications

Coxiella burnetii is the bacterial agent of Q fever in humans. Here, we describe a unique, ~7.2 kDa, surface-exposed lipoprotein involved in metal binding which we have termed LimB. LimB was initially identified as a potential metal-binding protein on far-Western (FW) blots containing whole-cell lysate proteins when probed with nickel-coated horseradish peroxidase (Ni-HRP) and developed with a chemiluminescent HRP substrate. The corresponding identity of LimB as CBU1224a was established by matrix-assisted laser desorption ionization-tandem time-of-flight mass spectrometry. blast analyses with CBU1224a showed no significant similarity to sequences outside strains of C. burnetii. Additional in silico analyses revealed a putative 20 …

Modulation Of Glutamate-Mediated Neuronal Cell Death By Neurosteroids, Benjamin J. Phelps

Undergraduate Theses and Capstone Projects

Traumatic brain injury (TBI) is a major cause of death and permanent disability in the United States. Approximately 1.7 million cases of TBI are reported annually. After an injury to the head, excessive glutamate, an excitatory neurotransmitter, is released into the extracellular fluid resulting in the excitotoxic death of neuronal tissue. Recent studies have suggested neurosteroids, may serve as an effective means by which to modulate excitotoxicity via the excitatory neurotransmitter alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). Using mixed astrocyte-neuronal cell cultures (14-16 DIV) exposed to increasing concentrations of AMPA as the model for TBI, the experiments examined the effect of the neurosteroids, …

Structure/Function Assessment Of Synapses At Motor Nerve Terminals, Andrew Fredericks Moser Johnstone, Kert Viele, Robin L. Cooper

Biology Faculty Publications

The release of transmitter at neuromuscular junctions (NMJ) of the opener muscle in crayfish is quantal in nature. This NMJ offers the advantage of being able to record quantal events at specific visually identified release sites, thus allowing measurement of the physiological parameters of vesicle release and its response to be directly correlated with synaptic structure.

These experiments take advantage of areas between the varicosities on the nerve terminal that we define as "stems." Stems were chosen as the region to study because of their low synaptic output due to fewer synaptic sites. Through 3D reconstruction from hundreds of serial …

Activation Of Amp-Activated Protein Kinase As An Early Indicator For Stress In The Lobster, Homarus Americanus, Stephanie Podolski

All Theses And Dissertations

Variations in water temperature, salinity, pH, and oxygen concentration are stressors that marine invertebrates face on a daily basis. Each of these physiological stressors creates a large cellular demand for energy. In mammals, energy metabolism is regulated by the enzyme AMP-activated protein kinase (AMPK), which is highly conserved during evolution. This project was designed to test the hypothesis that AMPK is present and activated by temperature, hypoxia, and anoxia stress in the lobster, Homarus americanus.

Animals were exposed to a rapid and progressive increase in temperature (6ºC per hour) beginning at 14 ºC. We measured lactate concentrations and AMPK …

Draft Western Rock Lobster Fishery Environmental Management Strategy November 2010 – October 2015, Department Of Fisheries

Fisheries Occasional Publications

No abstract provided.

Stem Cell Biology And Strategies For Therapeutic Development In Degenerative Diseases And Cancer, Angel A. Alvarez '98

Doctoral Dissertations

Stem cell biology is an exciting field that will lead to significant advancements in science and medicine. We hypothesize that inducing the expression of stem cell genes, using the embryonic stem cell gene nanog, will reprogram cells and dedifferentiate human mesenchymal stem cells into pluripotent stem cells capable of neural differentiation. The aims of initial studies are as follows:

Aim 1: Demonstrate that forced expression of the embryonic stem cell gene nanog induces changes in human mesenchymal stem cells to an embryonic stem cell-like phenotype.

Aim 2: Demonstrate that induced expression of nanog up-regulates the expression of multiple embryonic stem …

Uptake Of Nanoparticles Of Cerium Oxide And Yttrium Oxide By Acanthamoeba Castellanii (Protozoa) And Daphnia Magna (Crustacea), James R. Palmieri, Geneva Gehring, Catherine Minichino, Shaadi F. Elswaifi

Virginia Journal of Science

Currently, nanoparticles are synthesized and used at an unprecedented rate for industrial, medical, and research applications. The use of cerium oxide nanoparticles (CeONP) and yttrium oxide nanoparticles (YtONP) results in their spread as contaminants into the environment. Once in the environment, CeONP and YtONP can be taken up by organisms in the food chain where they may pose a public health risk. In this study we determine whether Acanthamoeba castellanii and Daphnia magna uptake CeONP or YtONP from their environment and thereby play a role in the transmission of the nanoparticles. Using electron microscopy, orgranisms exposed to the nanoparticles were …

Dayton, Ohio: A Study, Nolan Nicaise

Honors Theses

The urban forest is an important element of cityscapes today. Urban trees provide a habitat to wildlife populations, create more tolerable city living conditions, and better the lives of residents around them. The urban forest, however, is not distributed equitably to the urban population, and some residents receive more or less of its positive externalities. Montgomery County, Ohio, was chosen as the study site to determine if environmental injustice was present regarding the urban forest. It was found that there was environmental injustice present in Montgomery County, as the density of the urban forest was limited by the educational obtainment …

Monitoring Nesting Trends And Hatchling Success Of The Green Turtle (Chelonia Mydas) Population On Mnemba Island, Zanzibar, Taylor Dunbar

Independent Study Project (ISP) Collection

The nesting trends and hatching success of Green sea turtles (Chelonia mydas) were studied on Mnemba Island. This study involved a continuation of data collection for the ongoing monitoring program of sea turtles on Mnemba Island. Data was collected from nesting females as well as from post hatching nest excavations. The data that has been collected over the course of ten years was then analyzed to examine trends over time as well as to assess the current status of the turtle population on Mnemba Island. Hatch success as a function of different seasons was analyzed. It has been concluded that …

Effect Of Animal Facility Construction On Basal Hypothalamic-Pituitary-Adrenal And Renin-Aldosterone Activity In The Rat, Hershel Raff, Eric D. Bruder, William E. Cullinan, Dana R. Ziegler, Eric P. Cohen

Biomedical Sciences Faculty Research and Publications

Nearby construction can cause subtle, but important activation of the hypothalamic-pituitary-adrenal axis in laboratory rats.

Although loud noise and intense vibration are known to alter the behavior and phenotype of laboratory animals, little is known about the effects of nearby construction. We studied the effect of a nearby construction project on the classic stress hormones ACTH, corticosterone, renin, and aldosterone in rats residing in a barrier animal facility before, for the first 3 months of a construction project, and at 1 month after all construction was completed. During some of the construction, noise and vibrations were not obvious to investigators …

Characterization Of Microbial Community Structure In The Octocoral Leptogorgia Virgulata, Blair E. Armistead

Honors Theses

The process of spicule formation in L. virgulata results in a drop in pH, which, if left unregulated, could lead to demineralization and subsequent animal death. Carbonic anhydrase has been suggested as a possible pH regulatory mechanism in L. virgulata tissues. This study focuses on an additional hypothetical mechanism of pH regulation involving the production of urease by endosymbiotic bacteria living within L. virgulata tissue. PCR and DGGE are used as culture-independent methods to characterize facets of microbial community structure on L. virgulata in order to identify one …

Multilocus And Parametric Analyses Of The Evolutionary History Of The Amazonian Peacock Cichlids, The Genus Cichla (Teleostei: Cichlidae), Stuart Clayton Willis

School of Biological Sciences: Dissertations, Theses, and Student Research

Accurate knowledge of species boundaries and species phylogeny are fundamental to testing hypotheses of recent evolutionary processes, but the estimation of these partitions is challenging due both to inherent confusion about what is being estimated as well as the data available to estimate them. Using multilocus data from mtDNA, microsatellites, and nuclear locus sequences of over 1100 individuals, we delimited eight separately evolving species of Cichla rather than the 15 described. Among species we found evidence of rare but widespread introgressive hybridization, while within these species we observed evidence of long-term gene exchange and constrained evolutionary trajectories. In most cases …

Color Polymorphism Of Sand Crabs, Lepidopa Benedicti (Decapoda: Anomura: Albuneidae), Unnam Nasir, Zen Faulkes

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Sand crabs (Lepidopa benedicti) are highly specialized digging animals that spend the vast majority of their adult life submerged in fine sand. The carapace color of L. benedicti varies from gray to white. Given that the environment in which they live is uniform and dark, most of the functional scenarios to explain color variation seem unlikely to apply. Carapace color has a bimodal distribution, indicating that it is better characterized as a polymorphism than simply as normal variation. Gray crabs are larger and more common than white ones. Crabs mostly swim ventral-side up, which suggests that countershading does …

Protection Against Divergent Influenza H1n1 Virus By A Centralized Influenza Hemagglutinin, Eric A. Weaver, Adam M. Rubrum, Richard J. Webby, Michael A. Barry

School of Biological Sciences: Faculty Publications

Influenza poses a persistent worldwide threat to the human population. As evidenced by the 2009 H1N1 pandemic, current vaccine technologies are unable to respond rapidly to this constantly diverging pathogen. We tested the utility of adenovirus (Ad) vaccines expressing centralized consensus influenza antigens. Ad vaccines were produced within 2 months and protected against influenza in mice within 3 days of vaccination. Ad vaccines were able to protect at doses as low as 107 virus particles/kg indicating that approximately 1,000 human doses could be rapidly generated from standard Ad preparations. To generate broadly cross-reactive immune responses, centralized consensus antigens were constructed …

Increased Population Sampling Confirms Low Genetic Divergence Among Pteropus (Chiroptera: Pteropodidae) Fruit Bats Of Madagascar And Other Western Indian Ocean Islands, Lauren M. Chan, Steven M. Goodman, Michael D. Nowak, David W. Weisrock, Anne D. Yoder

Biology Faculty Publications

Fruit bats of the genus Pteropus occur throughout the Austral-Asian region west to islands off the eastern coast of Africa. Recent phylogenetic analyses of Pteropus from the western Indian Ocean found low sequence divergence and poor phylogenetic resolution among several morphologically defined species. We reexamine the phylogenetic relationships of these taxa by using multiple individuals per species. In addition, we estimate population genetic structure in two well-sampled taxa occurring on Madagascar and the Comoro Islands (P. rufus and P. seychellensis comorensis). Despite finding a similar pattern of low sequence divergence among species, increased sampling provides insight into the phylogeographic history …