• Anion Monitoring of Rae's Creek by Ion Chromatography

      Walton, Amberly; Department of Chemistry and Physics (Augusta University, 2018-12)
      Golf courses generally require large amounts of fertilizer to maintain their course appearance. Fertilizer is a source of phosphate- and nitrogen-based compounds. These compounds can have negative effects on aquatic life if there are large amounts introduced to the surface water. The effect of a golf course on anion concentrations in Rae’s Creek was studied using ion chromatography. Over the course of one year, the following anions were tracked: nitrate, nitrite, sulfate, phosphate, bromide, and chloride. The concentrations of the anions were high enough to allow quantitative measurements and changes were observed, but the concentrations remained below EPA guidelines for streams.
    • CBD Analysis in Oils and Foods

      Foley, Joanna; Department of Chemistry and Physics (Augusta University, 2020-05)
      Cannabidiol (CBD) has become a very prominent topic in the medical community and popular marketplace because of its widespread consumer use. Tetrahydrocannabinol (THC) and other similar molecules can be present in commercial CBD products, so testing is necessary to determine the presence of the CBD. Existing methods of analysis for CBD oils are only known on GC-FID (gas chromatography – flame ionization detector) and these methods are not optimal for the wide variety of commercial CBD products available. Thus, a GC-MS (mass spectroscopy) method, based on a published GC-FID method, was created to optimize the detection of CBD because not only separation but also identification can be obtained. This method can be applied to a wide variety of foods, gummies, and other items that may contain CBD and similar molecules. The method has been optimized by varying GC column temperature, and sample preparation, to find a balance between analysis time, analyte detection, and resolution for the various types of cannabinoid molecules present in commercial CBD oil samples. The optimized method was able to determine that a 1:3 ratio of oil to solvent gave optimal signal of all CBD oils tested. The optimized method was then tested on a variety of commercial and self-prepared CBD edibles to determine that CBD was still present and was not degraded into THC.
    • Characterization of 5HT1B and 5HT7 using Bioluminescence Resonance Energy Transfer

      Adams, Elizabeth; Department of Chemistry and Physics (Augusta University, 2019-05)
      GPCRs play a major role in cell signaling through their interactions with heterotrimeric G proteins. In conventional models of GPCR-G protein coupling, agonist binding promotes a conformational change within the receptor, which then associates with G proteins, facilitating the exchange of GDP for GTP. GTP-bound G proteins dissociate from the receptor and exert their effects on downstream signaling molecules. Previous studies suggest that serotonin 5HT7 receptors associate with Gs heterotrimers prior to agonist binding, and that 5HT7-Gs complexes dissociate after the G protein is activated. Here we study this unconventional mode of coupling using bioluminescence resonance energy transfer (BRET) between luciferase-tagged 5HT7 receptors and Gs heterotrimers labeled with Venus. Our results confirm that 5HT7 receptors interact with inactive (GDP-bound) Gs heterotrimers in the absence of an agonist, and that this interaction is stabilized by the inverse agonist methiothepin. Stimulation with the endogenous agonist serotonin (5HT) decreased BRET between 5HT7 receptors and Gs, indicating that the activation of the receptor leads to 5HT7-Gscomplex dissociation. Interestingly, Gs activation was not required for complex dissociation. These results are consistent with the hypothesis that 5HT7 receptors couple to Gs heterotrimers via an unconventional mechanism involving ligand-sensitive complexes of receptors and inactive Gs.
    • Creating a Drug Sensitive Strain of Pichia Pastoris by Deleting Putative Multi-Drug Transport Protein Transcription Factors

      Jones, Preston Dimitri; Department of Chemistry and Physics (Augusta University, 2015-05)
      Commonly known as baker’s yeast, Saccharomyces cerevisiae is a strain of yeast that has been extensively studied genetically. In S. cerevisiae, the expression of multi-drug transport proteins (MDTPs) is found to be under the control of transcription factors, PDR1 and PDR3. Deletion of these genes in S. cerevisiae leads to decreased expression of MDTPs and decreased efficiency in drug export. Mutant strains of this yeast can be used in experiments involving the introduction of drugs into the yeast. Many experiments require a drug-protein interaction, and examining the results of this interaction is the subject of many genetic studies (1). These studies often involve the purification of the protein of interest after drug manipulation has occurred. Pichia pastoris is a better strain of yeast to use in these experiments because it grows to higher cell densities in fermentation than S. cerevisiae, providing more protein to work with. The goal of this project is to create a drug sensitive strain of P.pastoris by deletion of transcription factors that are homologous to those already characterized in S. cerevisiae. Putative MDTP transcription factors in P.pastoris have been determined via a blast search comparing the P. pastoris genome to S. cerevisiae. The results found three candidate genes, 0203, 0233, and 0322 that matched with the PDR1 and PDR3 genes in S.cerevisiae (2). We hypothesize that knocking out one or more of these genes will cause decreased expression of MDTPs in our mutant strain. Using homologous recombination and two selectable markers (ability to synthesize histidine and resistance to the toxin G418), we have successfully knocked out all 3 of these genes individually and have created two double knockout strains (0233-0322 and 0203-0233). Drug sensitivity assays in which we grew the mutant strains on plates with doxorubicin or camptothecin showed no enhancement in drug sensitivity (all strains were still able to grow when incubated with the toxin). Because we cannot measure the expression of MDTPs directly, we use this assay to indirectly relate the growth of the yeast in the presence of a drug to expression of MDTPs. The continued growth of our mutant yeast strains leads us to believe that all three genes must be deleted in a single strain to cause reduced MDTP expression. It is also possible that our deletion had an effect that was immeasurable by a growth assay.
    • Curcumin Conjugates as Potential Therapeutics for Breast Cancer

      Tran, Queen; Chemistry and Physics (Augusta University Libraries, 2020-05-04)
      This item presents the abstract for an oral presentation at the 21st Annual Phi Kappa Phi Student Research and Fine Arts Conference.
    • Design and Synthesis of Novel NSAID Hybrid Conjugates as Potential Anti-inflammatory

      Honkanadavar, Hitesh; Department of Chemistry and Physics (Augusta University, 2019-05)
      Non-steroidal anti-inflammatory drugs are one of the most common drugs administered worldwide as highly effective analgesic, antipyretic and anti-inflammatory agents. The drugs function by inhibiting the COX-2 enzyme system which leads to a decrease in inflammation; however, the drugs also inhibit the COX-1 enzyme system which is critical to maintaining the integrity of the stomach lining as well as proper kidney function. Inhibition of this enzyme system can lead to stomach ulcers and kidney dysfunction. Hybrid conjugates of existing non-steroidal anti-inflammatory drugs (NSAIDs) have already been synthesized with ibuprofen, acetaminophen, and amino acids to increase potency and decrease toxicity. Computational chemistry studies of these compounds show that the free phenol moiety in acetaminophen plays a greater role in the inhibition of the COX-2 enzyme system than the amine moiety. The previous compounds utilized the phenol moiety to form the product. New hybrid conjugates of ibuprofen and acetaminophen via amino acid linkers have been synthesized, leaving the phenol moiety free. The compounds have been characterized by nuclear magnetic resonance and infrared spectroscopy. Biological studies indicate that some of the synthesized compounds are showing improved potency when compared to ibuprofen alone as well as decreased ulcer formation.
    • Design and Synthesis of Selective COX-2 Inhibitors as Potential Anti-Inflammatory Agents

      Wade, Margaret; Chemistry and Physics (Augusta University Libraries, 2020-05-04)
      This item presents the abstract for an oral presentation at the 21st Annual Phi Kappa Phi Student Research and Fine Arts Conference.
    • Design, Synthesis, and Computational Studies of Isoniazid Hybrid Conjugates as Potential Antimycobacterial Agents

      Thomas, Eyana; Chemistry and Physics (Augusta University Libraries, 2020-05-04)
      This item presents the abstract for an oral presentation at the 21st Annual Phi Kappa Phi Student Research and Fine Arts Conference.
    • Enhancing Radiation Sensitivity in Anaplastic Thyroid Cancer: Novel Therapeutic Strategies to Target a Killer

      Latremouille, Rachel; Department of Chemistry and Physics (Augusta University, 2015-12)
      Anaplastic thyroid carcinoma (ATC) is an aggressive cancer, with those diagnosed typically living only sixth months. This cancer normally effects the elderly, with an estimated 67% of patients being 70 years of age or older. One of the reasons ATC is such a deadly disease is the lack of effective treatment options. While chemotherapy and radiation are effective treatments for many cancers, they usually have little efficacy for ATC patients. However, previous research conducted by our lab has discovered that cytokeratin-8 (CK8), a protein that plays a structural role in normal cells, has a novel and unanticipated role in promoting growth of ATC cells. Knockdown of CK8 in fast-growing ATC results in in a near-complete abrogation of cell growth, and an increase in apoptosis, in which the cell programs itself to die. Since ATC is normally resistant to radiation therapy, and one of the mechanisms of action for radiation in treating cancer is inducing DNA damage and subsequently apoptosis, we hypothesized there may be the potential for increased effectiveness between these two observations. However, due to difficulties with the clonogenic assay we originally planned to do, our research project is still ongoing.
    • Exploring Music's Effects on Blood Pressure and Heart Rate Through Changes in Oxytocin Levels

      Cauthron, Steven; Department of Chemistry and Physics (Augusta University, 2017-12)
      High blood pressure and high heart rate can increase chances of a variety of diseases. This study looked at the impact of music on blood pressure and heart rate in pre-hypertensive individuals based on changes in their oxytocin levels. We hypothesized that listening to music would result in an increase in oxytocin and therefore a decrease in blood pressure and heart rate. This study involved 16 pre-hypertensive individuals. Hemodynamic measurements and oxytocin counts were obtained in three different experimental conditions: rest (control), stressed and after listening to music. The study results indicated a significant reduction in heart rate after listening to music. There was no significant change in blood pressure after listening to music. The results of this study show that listening to music is associated with higher oxytocin levels.
    • Investigation of the Properties of Stem Loop DNA

      Benny, Reshma; Department of Chemistry and Physics (Augusta University, 2017-05)
      DNA or deoxyribonucleic acid is the genetic material of almost all living organisms and it is a polymer of deoxynucleotide monomers that are linked together by phosphodiester bonds. Each deoxynucleotide consists of a phosphate group and a nitrogen-containing base that are both attached to a 5-carbon sugar known as deoxyribose. The nitrogenous bases found in DNA are adenine (A), cytosine (C), guanine (G), and thymine (T). The primary structure of DNA consists of a single DNA strand with two distinct ends. The 5’ end, in most cases, terminates in a phosphate group and the 3’ end terminates in the hydroxyl group on a sugar molecule. When two strands of DNA come together to form a double helix, the strands lie anti-parallel to each other, where the 5’ end of one strand will align with the 3’ end of another strand; this helix depicts the tertiary structure and the most common form of DNA (Figure 1). The two strands of DNA are held together by complementary base pairing which involves the specific interaction of A with T and G with C. These base pairs are stabilized by hydrogen bonds and stacking interactions.[Introduction]
    • Iron, Copper, Nickel, and Zink Ion Concentrations in Rae's Creek

      Bridgers, Aerial; Department of Chemistry and Physics (Augusta University, 2018-12)
      Heavy metals can enter water systems through a variety of methods, such as through soil run-off, rain, or industrial activity near the system. Many of these heavy metals are toxic to both the wildlife and people around the system if present in high enough concentrations. The aim of this research was to create a model for a local water system, Rae's Creek, outlining the concentrations of iron, copper, nickel, and zinc present throughout a seven-month period. Additionally, this research sought to pinpoint any correlation between increases in metal concentrations and outside events, such as rain or the Master's Tournament held yearly in Augusta. Results indicated that copper and zinc concentrations were well above guidelines set for recreational water quality by the Environmental Protection Agency, while iron and nickel concentrations were generally below the limitations set for their concentrations. While rain had no observed effect on the heavy metal concentrations, there are two specific dates where all four metals had a marked increase in concentration. However, it is inconclusive as to what caused this increase.
    • A MATLAB GUI to study Ising model phase transition

      Thornton, CurtisLee; Datta, Trinanjan; Department of Chemistry and Physics (2016-03-14)
      We have created a MATLAB based graphical user interface (GUI) that simulates the single spin flip Metropolis Monte Carlo algorithm. The GUI has the capability to study temperature and external magnetic field dependence of magnetization, susceptibility, and equilibration behavior of the nearest-neighbor square lattice Ising model. Since the Ising model is a canonical system to study phase transition, the GUI can be used both for teaching and research purposes. The presence of a Monte Carlo code in a GUI format allows easy visualization of the simulation in real time and provides an attractive way to teach the concept of thermal phase transition and critical phenomena. We will also discuss the GUI implementation to study phase transition in a classical spin ice model on the pyrochlore lattice.
    • Novel Use of Stem-loop DNA in SELEX

      Coe, Genevieve; Department of Chemistry and Physics (Augusta University, 2015-05)
      Aptamers are composed of oligonucleotides and are most recognized for their ability to function much like antibodies. Unlike antibodies, aptamers can be generated in vitro, have a longer shelf life and are potentially faster to synthesize. The current method of aptamer generation is through a cycle known as SELEX, which stands for Systematic Evolution of Ligands through Exponential Enrichment. The SELEX method traditionally uses a library of single-stranded DNA or RNA as a starting material, which is incubated with a target. The nucleotides that bind to the target are separated from the unbound nucleotides, eluted from the target and amplified by PCR. The amplified nucleotides go through several more cycles of SELEX until aptamers with a high binding affinity for the target are produced. Before the double-stranded products from PCR can be used in another cycle they have to be separated into single-strands. The process of regenerating single-stranded DNA from double-stranded DNA is often time consuming and results in a low product yield, decreasing the efficiency of the SELEX process. In order to improve the efficiency of aptamer generation, we explored the use of a novel starting material based on its potential to make SELEX a more automated process. Stem-loop DNA has both double-stranded and single-stranded DNA portions due to its unique secondary structure. It has the ability to retain the single-stranded portion of its special conformation after PCR amplification. After characterization of a specifically designed stem-loop, we incorporated the use of stem-loop DNA as a starting material in SELEX to potentially bypass the regeneration of single-strand DNA in SELEX. The success of this modified approach to SELEX could result in a more efficient method for the generation of aptamers.
    • Spin wave Feynman diagram vertex computation package

      Price, Alexander; Javernick, Philip; Datta, Trinanjan; Department of Chemistry and Physics (2016-03-14)
      Spin wave theory is a well-established theoretical technique that can correctly predict the physical behavior of ordered magnetic states. However, computing the effects of an interacting spin wave theory incorporating magnons involve a laborious by hand derivation of Feynman diagram vertices. The process is tedious and time consuming. Hence, to improve productivity and have another means to check the analytical calculations, we have devised a Feynman Diagram Vertex Computation package. In this talk, we will describe our research group’s effort to implement a Mathematica based symbolic Feynman diagram vertex computation package that computes spin wave vertices. Utilizing the non-commutative algebra package NCAlgebra as an add-on to Mathematica, symbolic expressions for the Feynman diagram vertices of a Heisenberg quantum antiferromagnet are obtained. Our existing code reproduces the well-known expressions of a nearest neighbor square lattice Heisenberg model. We also discuss the case of a triangular lattice Heisenberg model where non collinear terms contribute to the vertex interactions.
    • Synthesis of Fluorine Substituted Derivatives of a Bicyclic Aryl Sulfone as Potential Inhibitors of HHV-6 and HCMV

      Rouillard, Kaitlyn R.; Department of Chemistry and Physics (Augusta University, 2015-05)
      Human herpesvirus 6 (HHV‐6) and human cytomegalovirus (HCMV) are two strains of betaherpesviruses. HHV‐6 causes roseola in children and retinitis in AIDS patients, and HCMV is the leading viral cause of birth defects, including deafness. There are no drugs specifically designed for HHV‐6, though the antivirals used to treat HCMV, foscarnet and ganciclovir, are used to treat HHV‐6 off‐label. However, both drugs exhibit toxicity that limits clinical usefulness. Our group, in collaboration with Dr. Lieve Naesens from Katholieke Universiteit in Leuven, Belgium, has developed a series of compounds that are effective at inhibiting HHV‐6 in a cell culture. A previously developed bicyclic sulfone compound has shown strong antiviral activity, and several derivatives of this compound have been synthesized in an effort to develop a more effective drug. Recent data has shown that bromine substituents on this compound increase antiviral activity, and in an attempt to further improve activity, a fluorine atom will be added as well. The specific purpose of this research is to investigate the antiviral activity of compounds with a fluorine substituent on the phenyl ring located at the 3‐position of the bicyclic sulfone ring system.
    • Synthesis of Novel G and N-Substituted Bicyclic Sulfones as Potential Inhibitors of Human Herpes Virus 6 (HHY,6)

      Murray, Emily J.; Department of Chemistry and Physics (Augusta University, 2013-05)
      Human herpes virus 6 (HHV-6) is a member of the betaherpesvirus family and one of eight known human herpes viruses. HHV-6 commonly manifests itself by age three in more than ninety percent of the world's population as roseola infantum, an illness characterized by upper respiratory congestion, fever, febrile seizure, and rash. HHV-6 is also thought to play a role in the progression of pathogenic diseases such as epilepsy, multiple sclerosis, chronic fatigue syndrome, and some cancers. Currently, only two drugs, Cytovene and Foscavir, are commonly used for treatment of HHV-6. Unfortunately, both have high toxicity levels and viral resistance is building against them. Previous research in our lab and that of our collaborator has shown that certain bi cyclic sulfones are potent inhibitors of HHV-6. Our goal in this research has been to develop C- and N-substituted analogs of the original lead compound. Currently, one novel compound that contains both a cyclopropyl group on the nitrogen and a benzyl group on one of the carbons has been successfully synthesized by a multi-step process beginning with lcyanomethylsuifonyl-2-fluorobenzene. Reactions employed in the synthesis include Nucleophilic Aromatic Substitution (NAS), Aldo! Condensation, and SN2 Substitution. This new sulfone derivative has been sent to the Rega Institute for Medical Research in Leuven, Belgium for testing, and we are currently awaiting antiviral results. Meanwhile, work is ongoing to create additional analogs for testing. This work was funded in part by the HHV-6 Foundation.