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Design, Synthesis And Biological Screening Of Novel Cucs-Inspired Estrone Analogs Towards Treatment Of Pancreatic Adenocarcinoma, Khaled Alseud 2019 South Dakota State University

Design, Synthesis And Biological Screening Of Novel Cucs-Inspired Estrone Analogs Towards Treatment Of Pancreatic Adenocarcinoma, Khaled Alseud

Electronic Theses and Dissertations

Pancreatic cancer is currently the fourth most deadly type of cancer globally. It is expected to become the second by 2030, due to its poor prognosis and its resistance to the current standard treatment, Gemcitabine. Moreover, the survival rate after treatment is low compared to other cancer types, which suggests an urgent need for new potent and safe treatment agents. Recently, the triterpenoid, cucurbitacin, has shown promising antiproliferative activity against human pancreatic cancer cells in a dose- and timedependent manner, and decreased pancreatic tumor size in combination with gemcitabine in vivo. However, the use of cucurbitacin in clinical studies has …


In-Silico Design And Synthesis Of Selective Estrogen Receptor Modulators Targeting Ovarian Cancer, John Apraku 2019 South Dakota State University

In-Silico Design And Synthesis Of Selective Estrogen Receptor Modulators Targeting Ovarian Cancer, John Apraku

Electronic Theses and Dissertations

The established records of the safety of Ormeloxifene along with its favorable bioavailability and ability to inhibit rapid cell proliferation in the endometrium during embryonic implantation has made it one of the best drug candidates for controlling undesirable rapid cell growth such as endometriosis and cancerous tumor conditions. Recent studies have confirmed the effectiveness of Ormeloxifene to suppress and inhibit epithelial-mesenchymal transition process as evidenced by repression of N-cadherin, slug, snail, vimentin, MMPs, β-catenin/TCF-4 transcriptional activity and induce the expression of pGSK3b. Recently conducted studies have revealed the dynamic binding of ormeloxifene with β-catenin, GSK3b, CDK4, and other downstream EGFR. …


Killing Breast Cancer One Porphyrin At A Time, Taylor C. Lymburner 2019 Ouachita Baptist University

Killing Breast Cancer One Porphyrin At A Time, Taylor C. Lymburner

Honors Theses

New treatments for cancer are continuously being developed and improved. One such treatment is Photodynamic Therapy, more commonly referred to as PDT. PDT is quickly becoming more popular due to its relative lack of side effects that are present in other treatments. In PDT, light-sensitive agents are required and are activated by light in the targeted cells. There are many types of PDT agents but the one focused on in this research is a four-pyrrole ring structure known as a porphyrin. The combination of H2 TPPC with 3- amino-oxetane-3-yl-methanol created the final product ofH2TPP-Oxo-MeOH. Once the porphyrin was formed, it …


Determination Of Bisphenol A (Bpa) In Infant Oral Hygiene Devices Using Fluorescence Spectrophotometry, Kaitlyn Thomason 2019 Ouachita Baptist University

Determination Of Bisphenol A (Bpa) In Infant Oral Hygiene Devices Using Fluorescence Spectrophotometry, Kaitlyn Thomason

Honors Theses

Bisphenol A (BPA) is an organic, solid substance that is structurally similar to estradiol, a naturally-occurring form of the female sex hormone estrogen. Since the 1957 discovery that BPA can function as an effective hardener, BPA-based plastics have been used to make a variety of consumer goods, such as water bottles, baby bottles, DVDs, eyeglass lenses, and medical devices, while BPA-based epoxy resins have been used to coat the insides of various food and drink containers, to line the insides of water pipes, and to create the thermal ink found on paper sales receipts. In recent years, however, numerous studies …


Oleic Acid Vesicles: Formation, Mechanisms Of Reactivity, And Uses In Determination Of Terpene Activity, Laura A. Walther 2019 University of Kentucky

Oleic Acid Vesicles: Formation, Mechanisms Of Reactivity, And Uses In Determination Of Terpene Activity, Laura A. Walther

Theses and Dissertations--Chemistry

This dissertation will focus on the volatile compounds released upon the burning of incense which are numerous and varied. The first part of this dissertation is the gas chromatography-mass spectral (GC-MS) analysis of burning incense collected via solid phase microextraction (SPME) with the aim of developing a library of compounds found in incense as used in the Orthodox church.

The second part of this dissertation has the aim of developing a method for forming oleic acid bilayer vesicle membranes and a fluorescence spectroscopy method by which the reactivities of these vesicles can be analyzed. These reactivities include permeability, fluidity, aggregation, …


Bottom-Up Lignomics: Towards The Development Of Adduct Electrospray Ionization Mass Spectrometric Methods To Characterize And Sequence Lignin Oligomers, Shardrack O. Asare 2019 University of Kentucky

Bottom-Up Lignomics: Towards The Development Of Adduct Electrospray Ionization Mass Spectrometric Methods To Characterize And Sequence Lignin Oligomers, Shardrack O. Asare

Theses and Dissertations--Chemistry

Lignin, the second most abundant naturally occurring polymer found in plant cell wall has the potential of becoming an alternative source for the production of chemical synthons for the pharmaceuticals and other chemical industries. While much gain has been made towards the development of degradation methods to break down lignin, effective analytical methods are still required to rapidly and accurately identify the products of lignin breakdown experiments. The goal of this work was to develop mass spectrometric methods for the characterization of lignin oligomers based on the study of model lignin compounds.

Unlike peptides and oligosaccharides, lignin model compounds that …


Investigation Of Amyloid Β Oligomer Dissociation Mechanisms By Single Molecule Fluorescence Techniques, Hope Cook Abdalla 2019 University of Kentucky

Investigation Of Amyloid Β Oligomer Dissociation Mechanisms By Single Molecule Fluorescence Techniques, Hope Cook Abdalla

Theses and Dissertations--Chemistry

Alzheimer’s disease (AD) is currently considered the most prevalent neurodegenerative disease and places a large financial burden on society as healthcare resources are limited and the disease does not have a cure. Alzheimer’s disease is characterized by the presence of amyloid beta (Aβ) plaques and neurofibrillary tangles; however current literature suggests Aβ oligomers are the main aggregating species leading to AD symptoms. Therefore, the underlying cause of Alzheimer’s, accumulation of amyloid beta, is currently being studied in hopes of developing treatment options. Our research aims at determining the mechanism and kinetics of Aβ oligomer dissociation into non-toxic monomers in the …


Investigation Of Thiol-Containing Biomarkers And Their Role In The Exposome, Tracy Gastineau-Stevens 2019 University of Kentucky

Investigation Of Thiol-Containing Biomarkers And Their Role In The Exposome, Tracy Gastineau-Stevens

Theses and Dissertations--Chemistry

Exposomics is an emerging area of study that looks at how the environment around a person or persons affects their overall health. Biomarkers have emerged as useful tools to better understand how the exposome affects a person. In this work, we investigate two potential endogenous biomarkers, homocysteine and glutathione that have been previously implicated in a number of diseases that have been linked to environmental causes. We also investigated an environmental exposure, the fungicide Ziram, which epidemiologically has been linked to diseases. In our investigation, we utilized capillary electrophoresis and capillary electrophoresis-mass spectrometry to develop a method for homocysteine and …


Oxidative Degradation Of Lignin And Investigation Of Utilization Of Lignin-Derived Materials As Building Blocks For Epoxy Resins, Zhen Fang 2019 University of Kentucky

Oxidative Degradation Of Lignin And Investigation Of Utilization Of Lignin-Derived Materials As Building Blocks For Epoxy Resins, Zhen Fang

Theses and Dissertations--Chemistry

Lignin, the second most abundant biopolymer on earth, is potentially a replaceable source for bulky fuels and chemical feedstocks. There have been numerous reports on methods for the oxidative cleavage of β-O-4 linkages but relatively few reports of how those methods affect other linkages that are present in lignin. We investigated how the β-1 and β-5 linkages respond under oxidative conditions proposed for lignin deconstruction based on their effect on β-O-4 linkages. Mechanochemical treatment of lignin can greatly improve the yield of monomer products and we applied a mechanochemical approach, using powerful ring-and-puck milling to promote lignin degradation. Along with …


Determination Of Bpa In Infant Oral Hygiene Products Using Fluorescence Spectrophotometry, Mallory K. Mayfield 2019 Ouachita Baptist University

Determination Of Bpa In Infant Oral Hygiene Products Using Fluorescence Spectrophotometry, Mallory K. Mayfield

Honors Theses

Bisphenol A (BPA) is commonly used to make plastics, and it is also used to make epoxy resin linings for metal food containers. People are exposed to this chemical daily through bottles, metal food containers, and other plastic products. BPA exposure has been linked to negative effects on the body including cardiovascular diseases, diabetes, and reproductive problems. Special caution should be taken for children because their systems are not fully developed, and they are often more susceptible to the negative effects. BPA can bind to estrogen receptors and activate them. It has this ability because of structural similarities to estradiol. …


Complex Mixtures: Identifying And Characterizing Secondary Organic Aerosols, Emma Quinn Walhout 2019 William & Mary - Arts & Sciences

Complex Mixtures: Identifying And Characterizing Secondary Organic Aerosols, Emma Quinn Walhout

Dissertations, Theses, and Masters Projects

Complex organic mixtures in the environment can contain hundreds to thousands of different organic molecules, and their composition and reactivity can have important environmental implications. In addition to gases, the atmosphere is made of a variety of small liquids and solids called aerosols. These aerosols have large impacts on human health, climate, and atmospheric chemical reactions. Here, secondary organic aerosol (SOA) from the ozonolysis of α-pinene is characterized. The atmospheric lifetime of SOA is very uncertain, but recent laboratory and modeling studies have demonstrated that photolysis is potentially an important process for organic mass loss from aerosol particles.1-5 Photolysis modifies …


Intramoleculer Hydrogen Bonding In Epoxide, Thiirane, Aziridine And Phosphirane Containing Cyclopentanols, Ben Edward Smith 2019 University of Mississippi

Intramoleculer Hydrogen Bonding In Epoxide, Thiirane, Aziridine And Phosphirane Containing Cyclopentanols, Ben Edward Smith

Electronic Theses and Dissertations

A recent computational analysis of the stabilizing intramolecular OH· · · O contact in 1,2-dialkyl-2,3-epoxycyclopentanol diastereomers has been extended to thiiriane, aziridine and phosphirane analogues. Density functional theory (DFT), second-order Møller-Plesset perturbation theory (MP2) and CCSD(T) coupled-cluster computations with simple methyl and ethyl substituents indicate that electronic energies of the cis isomers are lowered by roughly 3 to 4 kcal mol−1 when the OH group of these cyclopentanol systems forms an intramolecular contact with the O, S, N or P atom on the adjacent carbon. The results also suggest that S and P can participate in these stabilizing intramolecular interactions …


Ni And Au Transition Metal Complexes In The Photocatalytic Co2 Reduction Reaction, Shakeyia Davis 2019 University of Mississippi

Ni And Au Transition Metal Complexes In The Photocatalytic Co2 Reduction Reaction, Shakeyia Davis

Electronic Theses and Dissertations

The production of renewable fuels by the conversion of solar energy into chemical energy is a challenge. Photocatalytic and electrocatalytic conversion of CO2 to usable fuel precursors are approaches to overcoming this challenge. The two-electron reduction of carbon dioxide to carbon monoxide is an appealing process because CO can be used as a commodity chemical in industrial processes. Many molecular CO2 reduction catalysts have been reported and commonly use expensive late transition metals. These systems are inspired by natural photosynthesis and generally combine a photosensitizer, a catalyst, and a sacrificial electron donor. This work focuses nickel and gold complexes as …


The Development Of Novel Rhenium- And Copper-Based Molecular Catalysts For Applications In Energy Conversion Chemistry, Joseph Michael Lee 2019 University of Mississippi

The Development Of Novel Rhenium- And Copper-Based Molecular Catalysts For Applications In Energy Conversion Chemistry, Joseph Michael Lee

Electronic Theses and Dissertations

Since the Industrial Revolution, the consumption of fossil fuels has increased dramatically worldwide. The combustion of fossil fuels leads to the generation of carbon dioxide (CO2) emissions. CO2 is a greenhouse gas, but also a C1 feedstock that could be utilized for the generation of renewable fuels and commodity chemicals. However, CO2 is chemically inert and typically demands strong chemical reductants or very negative potentials before it undergoes conversion into reduced carbon products. The desire to carry out CO2 conversion in the presence of water presents a significant challenge, as protons may be reduced to hydrogen gas rather than facilitating …


Development Of Cobalt And Iron Catalysts Bearing Rigid Polydentate Ligands For Proton Reduction And C-H Bond Oxidation, Lizhu Chen 2019 University of Mississippi

Development Of Cobalt And Iron Catalysts Bearing Rigid Polydentate Ligands For Proton Reduction And C-H Bond Oxidation, Lizhu Chen

Electronic Theses and Dissertations

The demand for energy consumption has increased exponentially since the Industrial Revolution. The major source of this energy has been and continues to be fossil fuels. The depletion of fossil fuels and environmental concerns associated with their combustion has motivated us to develop a renewable energy alternative to meet future energy demands. Hydrogen is a clean energy alternative to fossil fuels, which can be generated from solar-driven water splitting. However, more efficient and inexpensive catalysts for the hydrogen evolution reaction (HER) are needed. In this context, hydrogen production has been investigated with a stable and highly reactive cobalt-based catalyst. While …


X-Ray Crystal Structure Of Au36(Sph-Pch3)24 Nanomolecules, Vigneshraja Ganeshraj 2019 University of Mississippi

X-Ray Crystal Structure Of Au36(Sph-Pch3)24 Nanomolecules, Vigneshraja Ganeshraj

Electronic Theses and Dissertations

Au36(SR)24 is one of the most comNanomolecules (NM) in gold NM field and crystal structures of Au36(SR)24 with different thiolate protecting ligand such as tert-butylbenzene thiol, thiophenol and cyclopentane thiol have been reported. It has been predicted that aromatic thiol protected Au36(SR)24 NM have same core structures like the other reported Au36(SR)24 NMs. Due to the steric and electronic conjugation effects the staples on the gold core exhibit minor changes in the bond length without affecting the gold core. By varying the Gold:Thiol ratio the NM size can be controlled. Herein, we report the synthesis, isolation and characterization of two …


Ligand Effect On Gold Nanomolecules Demonstrated Using Aliphatic, Aromatic And Bulky Thiolate Ligands, Milan Rambukwella 2019 University of Mississippi

Ligand Effect On Gold Nanomolecules Demonstrated Using Aliphatic, Aromatic And Bulky Thiolate Ligands, Milan Rambukwella

Electronic Theses and Dissertations

Atomically precise thiolate protected gold nanoparticles (AuNPs) known as gold nanomolecules (AuNMs) are intensely pursued owing to their feasibility to elucidate their structure by single crystal X-ray crystallography. They have distinct number of Au atoms (n) and thiolate (-SR, R-hydrocarbon chain) ligands (m) with molecular formula of the form [Aun(SR)m]. AuNMs are made of a gold core protected by a thiolate-monolayer and possess size-dependent properties conferred by quantum confinement. Atomic precision has been achieved in the 1-3 nm range and crystal structures of several AuNMs ranging from 18 to 279gold atoms have been studied. They provide significant insights into the …


Detecting Cyanobacteria Toxins: The Human Health Impact Of An Environmental Problem, Lillian E. Naimie 2019 Colby College

Detecting Cyanobacteria Toxins: The Human Health Impact Of An Environmental Problem, Lillian E. Naimie

Honors Theses

Cyanobacteria blooms are a growing concern in the world, as they can form a dense and sometimes toxin scum on water bodies. This paper will outline and discuss the environmental conditions that produce cyanobacteria bloom with a focus on the toxins produced by blooms and specifically the detection of these toxins through two analytical methods. Of the various toxins cyanobacteria are capable of producing, this paper will focus on microcystins and BMAA, a family of hepatotoxins and a specific neurotoxin respectively. The two analytical methods discussed are liquid chromatography coupled mass spectrometry and ELISA kit techniques. The advantages and drawbacks …


Avoiding Adverse Effects: New Ideas In Drug Discovery For Targeting Pparγ, Trey M. Patton 2019 University of Montana

Avoiding Adverse Effects: New Ideas In Drug Discovery For Targeting Pparγ, Trey M. Patton

Graduate Student Theses, Dissertations, & Professional Papers

Peroxisome proliferator-activated receptor gamma (PPARγ) has been a drug target to treat type 2 diabetes for the last 20 years when rosiglitazone and pioglitazone were approved by the FDA in 1999. While effective at increasing insulin sensitivity, these drugs cause serious adverse effects due to their full agonist characteristics. For that reason, drug discovery efforts have attempted to reduce or prevent the amount of agonist character of new PPARγ targeting ligands. Unfortunately, there have been no new FDA approved drugs for the receptor. There is a need for new ideas to produce better quality pharmaceuticals that lessen the impact of …


Silver Nanoparticles: An Effective Antibacterial Agent Against Gram-Negative Bacteria, Ashley M. Wilcox 2019 Wright State University

Silver Nanoparticles: An Effective Antibacterial Agent Against Gram-Negative Bacteria, Ashley M. Wilcox

Browse all Theses and Dissertations

A fourth of the world’s population lack access to safe water, thus the need for a more effective water treatment is imperative. Interest in silver nanoparticles (AgNPs) has grown in the last decade. Unlike chlorine, AgNPs do not form disinfection by products (DBPs), making them a prime candidate for drinking water treatment. The main aim of this study was to compare the antibacterial activity of electrochemical silver nanoparticles (eAgNPs-f) of ~5 nm in diameter against well-established pathogens: Escherichia coli (E. coli), Klebsiella variicola (K. variicola), and Pseudomonas aeruginosa (P. aeruginosa) to chlorine and Ag+ for drinking water. This was achieved …


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