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Progress Towards Heterocycles As Inhibitors Of Plasminogen Activator Inhibitor-1, Gregory Alan Abernathy

Master's Theses and Doctoral Dissertations

No abstract provided.

The Synthesis Of Amphiphilic Diblock Copolymers: An Investigation Into The Formation Of Micelles As A Function Of Hydrophobic Block Length, Kevin S. Kawchak

Master's Theses and Doctoral Dissertations

Acrylate-based amphiphilic diblock copolymers show great potential for anti-cancer drug transport due to their ability to aggregate into protective core-shell micelles. Using RAFT polymerization, copolymers containing poly(acrylic acid) and poly(methyl acrylate) blocks were made with high monomer conversion and narrow distributions of molecular weight for eventual use in medicinal applications. Based on previous findings of copolymers with low weight hydrophobic blocks failing to micellize, it was hypothesized that increasing the poly(methyl acrylate) block length would allow for micelle formation. 1H-NMR experiments conducted in the presence of an aqueous solution yielded diminished and broadened resonances of the lengthened hydrophobic block, which …

Synthesis And Purification Of Potential Antimicrobial Peptides, Christopher Ryan Snyder

Master's Theses and Doctoral Dissertations

No abstract provided.

Near Single-Molecule Sers-Based Detection Using Ultrafiltered, Unfunctionalized Silver Nanoparticles, Joshua Dale Baker

Browse all Theses and Dissertations

Silver nanoparticles (AgNPs) are currently widely-used in consumer products, therapeutics, biomedical devices, and electronics. Yet, one application for which AgNPs have been used extensively is surface-enhanced Raman spectroscopy (SERS)-based sensing. However, AgNP size and aggregation state are known to greatly influence these applications. This works aimed 1) to synthesize a large volume of unfunctionalized, Creighton AgNPs, to characterize their chemical and physical properties, 2) then to size-select AgNPs of 1-50 nm and 50-100 nm in diameter and to concentrate them using a three-step, "green" tangential flow ultrafiltration (TFU) process. 3) Finally, to determine and compare the SERS-based sensing capabilities of …

Micro-Raman Imaging And Hyperspectral Analysis Of Tibiotarsi From Chick Embryos Exposed To Sublethal Doses Of Platinum Group Metals, Adam Christopher Stahler

Browse all Theses and Dissertations

Platinum group metals (PGMs), i.e., Pd, Pt and Rh, are found at pollutant levels in the environment. PGMs accumulate in plant and animal tissues, and little is known about their toxicity. Our previous studies have shown that chick embryos exposed to 1.0 mL PGM solutions of 5.0 ppm (LD₅₀) and higher exhibited severe skeletal deformities. This work hypothesized that 1.0 ppm sublethal doses of PGMs would negatively impact the mineralization process in tibiotarsi. One milliliter of 1.0 ppm of Pd(II), Pt(IV), Rh(III) aqueous salt solutions and a PGM-mixture were injected into the air sac of the eggs …

Investigations Of Noncovalent Interactions Using Raman Spectroscopy And Electronic Structure Computations, Ashley Wright

Electronic Theses and Dissertations

This dissertation research focuses on the effects of noncovalent interactions on vibrational energy levels. Vibrational spectroscopy is a powerful tool for the study of the effects of weak intermolecular interactions such as hydrogen bonding and interactions with the environment, including solvation effects. Changes in the vibrational spectra of interacting molecules allow us to ascertain exactly which atoms and bonds are affected and to what extent they are affected. Quantum mechanical methods, ab initio theory and density functional theory, are employed to model molecular geometries, properties, and subtle interactions between molecules. Much of this research centers on the comparison of these …

Techniques For Sensor-Integrated Robotic Systems: Raman Spectra Analysis, Image Guidance, And Kinematic Calibration, Luke Anthony Reisner

Wayne State University Dissertations

Robotics and sensor technology have made impressive advancements over the years. There are now robotic systems that help perform surgeries or explore the surface of Mars, and there are sensors that detect trace amounts of explosives or identify diseased human tissue. The most powerful systems integrate robots and sensors, which are natural complements to each other. Sensors can provide information that might otherwise be unavailable due to indirect robotic manipulation (e.g., images of the target environment), and robots can provide suitably precise positioning of an analytical sensor.

To have an effective sensor-integrated robotic system, multiple capabilities are needed in the …

An Unexpected Stereochemical Insignificance Discovered In Acinetobacter Baumannii Quorum Sensing, Amanda L. Garner, Sook Kyung Kim, Jie Zhu, Anjali Kumari Struss, Richard Watkins, Brent D. Feske, Gunnar F. Kaufmann, Kim D. Janda

Chemistry: Faculty Publications (1990-2023)

Stereochemistry is a key aspect of molecular recognition for biological systems. As such, receptors and enzymes are often highly stereospecific, only recognizing one stereoisomer of a ligand. Recently, the quorum sensing signaling molecules used by the nosocomial opportunistic pathogen, Acinetobacter baumannii, were identified, and the primary signaling molecule isolated from this species was N-(3-hydroxydodecanoyl)-l-homoserine lactone. A plethora of bacterial species have been demonstrated to utilize 3-hydroxy-acylhomoserine lactone autoinducers, and in virtually all cases, the (R)-stereoisomer was identified as the natural ligand and exhibited greater autoinducer activity than the corresponding (S)-stereoisomer. Using chemical synthesis and biochemical assays, we have uncovered a …

Microscopic And Spectroscopic Analysis Of Wo3 And Ti-Doped Wo3 Thin Films, Young Taek Yun

Open Access Theses & Dissertations

Tungsten oxide (WO3) has been a subject of high interest for its unique properties, and recently for its importance in different types of industrial applications which ranges from non-emissive displays, optical, microelectronic, catalytic/photocatalytic, humidity, temperature, gas, and biosensor devices. In this study, WO3 and Ti doped thin films were prepared using radio frequency magnetron reactive sputtering at different substrate temperatures ranging from room temperature to 500 ºC in increments of 100 ºC. After forming a hypothesis based on knowledge of established WO3 properties, we attempt in this work to investigate how the doping influences the roughness and the mean grain …

Biochemical Actions Of A Novel Cis-Terpenone, Lin Zhang

Theses and Dissertations

Abstract BIOCHEMICAL ACTIONS OF A NOVEL CIS-TERPENONE By Lin Zhang, Ph.D. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2012 Director: Qibing Zhou, Ph.D Assistant Professor Department of Chemistry

Quinone methides are reactive species due to their electrophilicity, and natural quinone methide analogs have broad biological activities. Based on known actions of cytochrome P450 enzymes, we hypothesized that trans-terpenones can be metabolized in cells to form a cascade of metabolite products, which may be biologically active due to the generation of quinine and quinone methide …

Friedel-Crafts Acylation Studies On 3-Alkyl-1-(Phenylsulfonyl)Indoles Using Aluminum Chloride And Bismuth Triflate, Venkateswara Reddy Karrepu

Browse all Theses and Dissertations

Using the traditional catalyst, aluminum chloride in stoichiometric amounts, 3-alkyl-1-(phenylsulfonyl)indoles can be regioselectively acylated under Friedel-Crafts conditions at the C-6 position along with 10% of a minor isomer at the C-5 position. Alternatively, using catalytic amounts of the green catalyst, bismuth triflate, C-2 acylation was observed. Therefore, regioselectivity can be controlled by the nature of the Lewis acid catalyst. Moreover, this is the first-time that Friedel-Crafts acylation studies were demonstrated upon 3-alkyl-1-(phenylsulfonyl)indoles.

The Synthesis Of Room-Temperature Ionic Liquids And Their Metathesis Reactions With Dilithium Phthalocyanine, Andrew Michael Beauchamp

Browse all Theses and Dissertations

A series of alkoxyalkylammonium salts has been synthesized for use in metathesis reactions with dilithium phthalocyanine. The salts, which were ionic liquids at or near room temperature, were synthesized by a nucleophilic substitution of tris[2-(2-methoxyethoxy)ethyl]amine and iodomethane, iodoethane, bromoethane, 1-bromo-propane, 1-bromo-2-(2-methoxyethoxy)ethane, and [2-[2-(2-methoxyethoxy)ethoxy]-ethoxy] p-toluenesulfonate in yields ranging from 67% - 88%. The methyl, ethyl, propyl and tetra[2-(2-methoxyethoxy)ethyl]ammonium salts were obtained for use in metathesis reactions. The salts were liquid at room temperature, with the exception of tetra[2-(2-methoxyethoxy)ethyl]ammonium bromide which was found to melt at 46° and were thermally stable to approximately 200°. The four salts were used in metathesis reactions …

A Sers And Sem-Edx Study Of The Antiviral Mechanism Of Creighton Silver Nanoparticles Against Vaccinia Virus, Catherine Binns Anders

Browse all Theses and Dissertations

Silver nanoparticles (AgNPs) are well-recognized as antiviral agents but little is known about their mechanism of action. In this study, it was hypothesized that unfunctionalized, Creighton AgNPs of an average diameter of 11 nm will form covalent bonds with vaccinia virus (VV) mainly through the external, entry fusion complex (EFC) proteins. The EFC is housed on the external membrane of VV and contains 9-12 proteins having numerous cysteine groups, intramolecular disulfide bonds, aromatic moieties and myristic acids bound to the N-terminus of glycine residues. VV (1012 PFUs) was incubated at 37oC for one hour with Creighton AgNPs that were size …

Self-Assembling Subnanometer Pores With Unusual Mass-Transport Properties, Xibin Zhou, Guande Liu, Kazuhiro Yamato, Yi Shen, Ruixian Cheng, Xiaoxi Wei, Wanli Bai, Yi Gao, Hui Li, Yi Liu, Futao Liu, Daniel M. Czajkowsky, Jingfang Wang, Michael J. Dabney, Zhonghou Cai, Jun Hu, Frank V. Bright, Lan He, Xiao Cheng Zeng, Zhifeng Shao, Bing Gong

Xiao Cheng Zeng Publications

A long-standing aim in molecular self-assembly is the development of synthetic nanopores capable of mimicking the mass-transport characteristics of biological channels and pores. Here we report a strategy for enforcing the nanotubular assembly of rigid macrocycles in both the solid state and solution based on the interplay of multiple hydrogen-bonding and aromatic π − π stacking interactions. The resultant nanotubes have modifiable surfaces and inner pores of a uniform diameter defined by the constituent macrocycles. The self-assembling hydrophobic nanopores can mediate not only highly selective transmembrane ion transport, unprecedented for a synthetic nanopore, but also highly efficient transmembrane water permeability. …

Ccpa Regulates Arginine Biosynthesis In Staphylococcus Aureus Through Repression Of Proline Catabolism, Austin S. Nuxoll, Steven M. Halouska, Marat R. Sadykov, Mark L. Hanke, Kenneth W. Bayles, Tammy Kielian, Robert Powers, Paul D. Fey

Department of Chemistry: Faculty Publications

Staphylococcus aureus is a leading cause of community-associated and nosocomial infections. Imperative to the success of S. aureus is the ability to adapt and utilize nutrients that are readily available. Genomic sequencing suggests that S. aureus has the genes required for synthesis of all twenty amino acids. However, in vitro experimentation demonstrates that staphylococci have multiple amino acid auxotrophies, including arginine. Although S. aureus possesses the highly conserved anabolic pathway that synthesizes arginine via glutamate, we demonstrate here that inactivation of ccpA facilitates the synthesis of arginine via the urea cycle utilizing proline as a substrate. Mutations within putA, rocD, …

Unraveling The Structural Complexity In A Single-Stranded Rna Tail: Implications For Efficient Ligand Binding In The Prequeuosine Riboswitch, Catherine D. Eichhorn, Jun Feng, Krishna C. Suddala, Nils G. Walter, Charles L. Brooks Iii, Hashim M. Al-Hashimi

Department of Chemistry: Faculty Publications

Single-stranded RNAs (ssRNAs) are ubiquitous RNA elements that serve diverse functional roles. Much of our understanding of ssRNA conformational behavior is limited to structures in which ssRNA directly engages in tertiary interactions or is recognized by proteins. Little is known about the structural and dynamic behavior of free ssRNAs at atomic resolution. Here, we report the collaborative application of nuclear magnetic resonance (NMR) and replica exchange molecular dynamics (REMD) simulations to characterize the 12 nt ssRNA tail derived from the prequeuosine riboswitch. NMR carbon spin relaxation data and residual dipolar coupling measurements reveal a flexible yet stacked core adopting an …

Surfactant-Free Hybridization Of Transition Metal Oxide Nanoparticles With Conductive Graphene For High-Performance Supercapacitor, Wen Qian, Zhiqiang Chen, Steven Cottingham, William Alexander Merrill, Natasja A. Swartz, Andrea Goforth, Tami Lasseter Clare, Jun Jiao

Chemistry Faculty Publications and Presentations

In order to improve specific capacitance and limit electrical resistance, high-quality exfoliatedgraphene decorated with transition metal (Fe, Mn, Co) oxide nanoparticles (NPs) has been successfully synthesized without the use of surfactant via a simple, general, environmentally-friendly chemical process. The specific capacitance of as-prepared graphene/Mn₃O₄ composite reach 239.6 F/g, when employed as the anode material in neutral NaCl electrolyte solutions (cf. 98.2 F/g for pristine graphene and 141.4 F/g for pure Mn₃O₄ NPs), which indicate the synergetic effects from both graphene and attached Mn₃O₄ NPs. Moreover, the high conductivity of …

Diversity Of Archaeosine Synthesis In Crenarchaeota, Gabriela Phillips, Manal A. Swairjo, Kirk W. Gaston, Marc Bailly, Patrick A. Limbach, Dirk Iwata-Reuyl, Valérie De Crécy-Lagard

Chemistry Faculty Publications and Presentations

Archaeosine (G+) is found at position 15 of many archaeal tRNAs. In Euryarchaeota, the G+ precursor, 7-cyano-7-deazaguanine (preQ0), is inserted into tRNA by tRNA-guanine transglycosylase (arcTGT) before conversion into G+ by ARChaeosine Synthase (ArcS). However, many Crenarchaeota known to harbor G+ lack ArcS homologs. Using comparative genomics approaches, two families that could functionally replace ArcS in these organisms were identified: 1) GAT-QueC, a two-domain family with an N-terminal glutamine amidotransferase class-II domain fused to a domain homologous to QueC, the enzyme that produces preQ0; 2) QueF-like, a family homologous to the bacterial enzyme catalyzing the reduction of preQ0 to 7- …

Effects Of Arsenic And Uvb Radiation On Induction Of Cyclin D1 In Human Keratinocytes., Julian Gonzalez

Dissertations and Theses

Arsenic and Ultraviolet radiation B (UVB) are environmental toxins that have been linked to various epithelial cancers. Arsenic metabolism in humans leads to its collection in the skin, where it encounters and can act with known carcinogen UVB. Epidemiological evidence of the two toxins demonstrates their potential to affect signaling pathways, with various consequences. Here we employ an in vitro model system using Normal Human Epidermal Keratinocytes (NHEK) to identify the effect of arsenic and UVB on humans and whether they work synergistically. We find that although both cause induction of cyclin D1, culturing cells with both co-mutagens does not …

Azide-Benzyne Cycloaddition And Olefination To Vinyl Benzotriazoles, Singh Govindra

Dissertations and Theses

No abstract provided.

Chemical And Biological Evaluation Of Antibiotic-Based Ionic Liquids And Gumbos Against Pathogenic Bacteria, Marsha Rae Cole

LSU Doctoral Dissertations

The research presented in this dissertation explores a novel pragmatic therapeutic approach for control, prevention, and treatment of infectious disease using Active-Pharmaceutical Ingredient-based Ionic Liquids (API-ILs) and Groups of Uniform Materials Based on Organic Salts (GUMBOS). Accordingly, several antiseptic- and antibiotic-based API-ILs and GUMBOS were synthesized and characterized using a combination of analytical and microbiological techniques. Overall, this research presents an advanced alternative to combination antibiotic therapy by using a novel group of ionic antimicrobial materials that have controlled pharmacokinetics, improved bioavailabilities, reduced toxicities, multi-modal properties, and potent antimicrobial spectrum of activity as a viable alternative to combating bacterial infections. …

Oxidative Stress And Down Syndrome: A Route Toward Alzheimer-Like Dementia, Marzia Perluigi, D. Allan Butterfield

Chemistry Faculty Publications

Down syndrome (DS) is one of the most frequent genetic abnormalities characterized by multiple pathological phenotypes. Indeed, currently life expectancy and quality of life for DS patients have improved, although with increasing age pathological dysfunctions are exacerbated and intellectual disability may lead to the development of Alzheimer's type dementia (AD). The neuropathology of DS is complex and includes the development of AD by middle age, altered free radical metabolism, and impaired mitochondrial function, both of which contribute to neuronal degeneration. Understanding the molecular basis that drives the development of AD is an intense field of research. Our laboratories are interested …

A New Method To Derive Electronegativity From Resonant Inelastic X-Ray Scattering, Stephane Carniato, Loic Journel, Renaud Guillemin, Maria Novella Piancastelli, Wayne C. Stolte, Dennis W. Lindle, Marc Simon

Chemistry and Biochemistry Faculty Research

Electronegativity is a well-known property of atoms and substituent groups. Because there is no direct way to measure it, establishing a useful scale for electronegativity often entails correlating it to another chemical parameter; a wide variety of methods have been proposed over the past 80 years to do just that. This work reports a new approach that connects electronegativity to a spectroscopic parameter derived from resonant inelastic x-ray scattering. The new method is demonstrated using a series of chlorine-containing compounds, focusing on the Cl 2p−1LUMO1 electronic states reached after Cl 1s→LUMO core excitation and subsequent KL radiative decay. Based on …

Volume 04, Matt Szemborski, Phillip Van Ness, Sarah Croughwell, Sarah Mayfield, Alyssa Strackbein, Marley Kimmel, Stephanie Skipp, Jamie Yurasits, Katherine Taggart, Alex Leonhart, Kristen Rawls, Andrew Armes, Amanda Haymens, Allison Paqlowski, Erica May, Stephanie Lane, Luke Acree, Cassandra L. Wilson, Stephanie Pishock, Erica Hopson, K. Juston Osborne, Katheryn Grayson, Kyle Fowlkes, Jessica Cox, Kaity Byrum, John-Harwood Scott, Ashley Johnson, Samantha Hockman, Emily Staskiel, Nancy Macdonald, R. Kruger Bressin, Benjamin P. Bilodeau, Andrea Irby, Kristin Macquarrie, Sarah Bietsch, Elizabeth Bednar

Incite: The Journal of Undergraduate Scholarship

Please note that part of pages 92-95 are redacted, in the digital copy, due to a misprint of the original printed article.

Introduction from Dean Dr. Charles Ross

The Internal Other: Transculturation and Postcolonial Magical Realism in Rushdie’s Midnight’s Children by Matt Szemborski

Photography by Phillip Van Ness

Photography “Waterfall” by Sarah Croughwell

Romancing the Bite: Statistical Analysis of Young Adult Vampire Novels by Sarah Mayfield

Photography by Alyssa Strackbein

Photography by Marley Kimmel

Wine and Society in the Viceroyalty of Peru by Stephanie Skipp

Analysis of Claud Monet’s Impression, Sunrise by Jamie Yurasits

Exploring Meaning: The Lindisfarne Gospels by …

Simultaneous Electrochemical Determination Of Tryptamine And Barbituric Acid, Luxshani Thangarajah

Masters Theses

The ability to analyze mixtures of two or more red-ox active components "on-the-spot" without the need to carry the sample into a laboratory is typically limited by the fact that various components need to be separated before they can be quantified. Reducing the two-step protocol (separation and detection) to a single one (detection) would markedly shorten the analysis time and simplify the analysis.

Exploring Phenyl Embrace Interactions In Trityloxy And Tritylamino Aromatic Compounds, Premnath Basa

Masters Theses

The area of supramolecular chemistry seeks to understand the organization of molecular structures and the interactions that hold such assemblies together by non-covalent interactions such as electrostatic, hydrogen bonding, π-π stacking interactions, and hydrophobic or solvatophobic effects. One such example that comes under supramolecular chemistry is the phenyl embrace interaction. These interactions occur due to the cooperative participation of at least three or more neighboring phenyl groups arranged as an interlocking propeller configuration to give complementary edge-to-face or offset face-to-face interactions. In order to understand the effect of functional groups on the tendencies of organic compounds to form phenyl embrace …

Photochemistry And Applications Of Diels-Alder Adducts And Photoacids In Materials Science, Valentine Johns

Electronic Theses and Dissertations

In chapter I Photo-retro-Diels-Alder (PrDA) reactions of a variety of Diels Alder (DA) adducts were studied. Experimental results showed that the photoreactivity (quantum yield) depends on the electron-donating ability of the diene component and the electronwithdrawing ability of the dienophile component. The mechanism was studied by trapping the reaction intermediate, O2 quenching and femtosecond time-resolved absorption spectroscopy. All the results support a mechanism that involves a charge-separated intermediate generated from a singlet excited state. The PrDA reaction may find applications in photoresponsive materials, photolithography, drug delivery and mechanistic research. Chapter II shows two applications of the PrDA reaction. The first, …

Conformational And Thermodynamic Properties Modulate The Nulceotide Excision Repair Of 2-Aminofluorene And 2-Acetylaminofluorene Dg Adducts In The Nari Sequence, Vipin Jain, Benjamin Hilton, Satyakam Patnaik, Yue Zou, M. Paul Chiarelli, Bongsup P. Cho

Chemistry: Faculty Publications and Other Works

Nucleotide excision repair (NER) is a major repair pathway that recognizes and corrects various lesions in cellular DNA. We hypothesize that damage recognition is an initial step in NER that senses conformational anomalies in the DNA caused by lesions. We prepared three DNA duplexes containing the carcinogen adduct N-(2'-deoxyguanosin-8-yl)-7-fluoro-2-acetylaminofluorene (FAAF) at G(1), G(2) or G(3) of NarI sequence (5'-CCG(1)G(2)CG(3)CC-3'). Our (19)F-NMR/ICD results showed that FAAF at G(1) and G(3) prefer syn S- and W-conformers, whereas anti B-conformer was predominant for G(2). We found that the repair of FAAF occurs in a conformation-specific manner, i.e. the highly S/W-conformeric G(3) and -G(1) …

A Seminaphthofluorescein-Based Fluorescent Chemodosimeter For The Highly Selective Detection Of Cysteine, Xiaofeng Yang, Yixing Guo, Robert M. Strongin

Chemistry Faculty Publications and Presentations

A fluorescent chemodosimeter for cysteine detection was developed based on a tandem conjugate addition and intramolecular cyclization reaction. The method exhibited an excellent selectivity for cysteine over other biothiols such as homocysteine and glutathione.

Selective Multivariate Applications In Forensic Science, Caitlin Rinke

Electronic Theses and Dissertations

A 2009 report published by the National Research Council addressed the need for improvements in the field of forensic science. In the report emphasis was placed on the need for more rigorous scientific analysis within many forensic science disciplines and for established limitations and determination of error rates from statistical analysis. This research focused on multivariate statistical techniques for the analysis of spectral data obtained for multiple forensic applications which include samples from: automobile float glasses and paints, bones, metal transfers, ignitable liquids and fire debris, and organic compounds including explosives. The statistical techniques were used for two types of …