Chemicals and Drugs Commons^™

Phytochemical And In-Vitro Cytotoxic Analyses Of Flavonoid Species Isolated From Chromolaena Leivensis, Luke A. Bryant

Electronic Theses and Dissertations

As a leading cause of death worldwide, cancer and its treatments remain a primary source of interest among researchers. Modern studies are looking into bioselective cytotoxicity to create new chemotherapies that do not have the same harsh side effects as those we use today. Natural product research has a promising future for the development of such treatments. Specifically, polar flavonoids may be the key to a bioselective treatment. Such flavonoid species are native to plants, often within flower petals or within the body. A natural antioxidant, they are designed not to harm healthy cells. This study focuses on the plant …

Safety Evaluation Of Epicertin, An Oral Biotherapeutic Candidate For Treating Ulcerative Colitis: A 28-Day Repeated Dose Toxicity Study., Jimmy Fernando Cifuentes Jimenez

Electronic Theses and Dissertations

Ulcerative colitis (UC) is an inflammatory bowel disease characterized by chronic, relapsing inflammation of the colon and rectum with limited treatment options. Among them, immunosuppressive agents have a high rate of adverse side effects and do not cure the disease. EPICERTIN (EPT), a recombinant variant of the cholera toxin B subunit (CTB) with a C-terminal hexapeptide extension consisting of a KDEL endoplasmic reticulum (ER) retention motif, is a promising oral biotherapeutic candidate for the treatment of UC. EPT has demonstrated mucosal healing activity in mouse models of colitis and human colonic explants. EPT's mechanism of action involves binding to GM1 …

Effect Of Histidine Tag On The Enzymatic Activity Of Pseudolysin And Its Interaction With The Streptomyces Metalloprotease Inhibitor (Smpi) Protein, Adewale Adeboye Adewole

Electronic Theses and Dissertations

Pseudolysin (PLN) protein is a major virulent factor in Pseudomonas aeruginosa infection. PLN belongs to the family of zinc-dependent metalloproteases. It is naturally inhibited by a smaller protein called streptomyces metalloprotease inhibitor (SMPI), secreted by Streptomyces nigrescens. Previous and current studies demonstrate that the interaction between PLN and SMPI offers unique mechanistic insights for drug development against infections caused by P. aeruginosa. This study investigated the effect of N-terminal Histidine (His) tag on the enzymatic activity of PLN and its interaction with SMPI. His-tagged PLN and SMPI proteins were expressed in bacteria and purified by affinity chromatography …

Cbl Regulation Of C-Met Signaling In Corneal Epithelial Cells., Kate Elise Tarvestad Laise

Electronic Theses and Dissertations

The cornea is the most anterior portion of the eye and permits light passage through to retina, allowing formation of a clear image as long as it remains healthy. If the cornea sustains damage, it creates and entrance for foreign body invasion, infection, and ultimately blindness in the immunocompromised eye. Healing the corneal tissue is critical for vision restoration and pain alleviation, as it is the most densely innervated tissue in the body. Growth factors and their cognate receptors are currently under investigation as tools to restore proper corneal physiology. We hypothesize that manipulating the hepatocyte growth factor (HGF) /c-Met …

Advancing Continuous Manufacturing: The Role Of Process Analytical Technology In Process Development, Samuel R. Henson

Electronic Theses and Dissertations

The pharmaceutical industry is actively pursuing technologies which improve manufacturing processes with the goal of producing high-quality pharmaceutical products for patients, manifesting in an industry-wide investment in continuous manufacturing (CM). Process analytical technology (PAT) has been recognized for its successful monitoring of critical quality attributes during routine production and is often cited alongside CM due to its ability to make timely, in-line measurements of intermediate materials. Various PAT tools are valuable in process development, particularly as continuous wet granulation processes are developed for use within pharmaceutical manufacturing. This work applied PAT and chemometric modeling during CM process development to enhance …

Method Development Of [3 + 2] Cycloadditions Using Tertiary Amine N-Oxides And Efforts Towards The First Total Synthesis Of Chrysosporazine D, Alexander Cocolas

Electronic Theses and Dissertations

Nitrogen-containing heterocycles are ubiquitous in bioactive molecules, pharmaceutical drugs, and natural products. For this reason, finding new and efficient ways to make such compounds remains a high priority for the organic and medicinal community. Our current endeavors build upon previously established work by our group, where we generated 1,2-diamines by coupling commercially available aldehydes with trimethylamine N-oxide (TMAO) in two steps. This route proved to be effective in generating 20+ novel 1,2-diamines and imidazolidines with a demonstrated ability to undergo transformations. Using this chemistry, we have developed a diastereoselective synthesis of 50+ novel 7-azanorbornanes using tertiary amine N-oxides …

Molecular Mechanisms Of Exercise-Stimulated Resolution Of Inflammation And Its Dietary Dependence., Ernesto H. Pena Calderin

Electronic Theses and Dissertations

Diet-induced obesity and adipose tissue (AT) inflammation that ensues sets the stage for systemic metabolic inflammation, disrupted insulin signaling, and eventual type 2 diabetes (T2D) development. At the center of this pathology lies a disruption in endogenous inflammation resolution pathways characterized by an imbalance in lipid mediator production (greater abundance of pro-inflammatory to pro-resolving lipids). Additionally, obese states are characterized by adrenergic deficiency, especially in response to physical activity. Inflammatory processes have been experimentally mitigated by either the pharmacological inhibition of pro-inflammatory signals (i.e., Leukotriene B₄ (LTB₄) and its receptor BLT1, which establishes a potent chemotactic stimulus …

Environmental Exposures And Aging., Daniel Chris Gomes

Electronic Theses and Dissertations

In recent years, research into air pollution has shown that exposure to certain components in air pollution, primarily PM2.5 can accelerate biological aging and thereby lead to increased susceptibility to multiple diseases. We hypothesize that prolonged exposure to air pollutants can result in premature aging leading to extensive tissue dysfunction and susceptibility to diseases. To examine this, we exposed mice to PM2.5 for 9, 15, and 21 days, then measured the telomere lengths, cellular senescence, and histone methylation patterns of multiple cell types. We found consistently increased telomere attrition, cellular senescence and advanced age-consistent histone methylation patterns in groups exposed …

Effects Of Environmental Pollutants On Liver Disease: Role Of The Gut-Liver Axis., Ngozi Victoria Adiele

Electronic Theses and Dissertations

Polychlorinated biphenyls (PCBs) and polystyrene (PS) microplastics are environmental pollutants associated with various diseases including toxicant associated fatty liver disease (TAFLD). Previously, exposure to Aroclor 1260 (a PCB mixture) has been shown to exacerbate TAFLD, partly through Aroclor 1260 induced gut dysbiosis. Studies has also demonstrated that PS exposure alters gut microbiome composition and induced obesity. However, the effects of Aroclor 1260 on the gut and the effects of PS on the liver are still understudied. Therefore, we hypothesize that environmental pollutants will disrupt the gut-liver axis through changes in gut and its microbiome as well as changes in liver …

Metabolic Foundations Of Exercise-Induced Cardiac Growth., Kyle Fulghum

Electronic Theses and Dissertations

Regular aerobic exercise promotes physiological cardiac growth, which is an adaptive response thought to enable the heart to meet higher physical demands. Cardiac growth involves coordination of catabolic and anabolic activities to support ATP generation, macromolecule biosynthesis, and myocyte hypertrophy. Although previous studies suggest that exercise-induced reductions in cardiac glycolysis are critical for physiological myocyte hypertrophy, it remains unclear how exercise influences the many interlinked pathways of metabolism that support adaptive remodeling of the heart. In this thesis project, we tested the general hypothesis that aerobic exercise promotes physiological cardiac growth by coordinating myocardial metabolism to promote glucose-supported anabolic pathway …

Early Detection Of Atypical Motor And Neurobehavior Of Infants At Risk Secondary To Opioid Exposure: A Prospective Study, Kara Boynewicz

Electronic Theses and Dissertations

Prenatal opioid exposure has been studied in relation to infants' medical outcomes. However, large gaps exist in the literature supporting early identification of atypical neurobehavior and motor development of infants with prenatal opioid exposure. The purpose of the study was to investigate whether prenatal opioid exposure has a negative influence on a newborn infant’s neurobehavior and motor development to aid in the early identification of potential delays. Using a prospective quasi experimental design, infants motor development using the Test of Infant Motor Performance (TIMP) and neurobehavior using the NICU Neonatal Network Scale (NNNS) was assessed on 58 infants in a …

Role Of Meibum And Tear Phospholipids In The Evaporative Water Loss Associated With Dry Eye., Samiyyah M. Sledge

Electronic Theses and Dissertations

It is generally believed that the tear film lipid surface film inhibits the rate of evaporation (Revap) of the underlying tear aqueous. It is also generally believed that changes in the composition of the tear film lipid layer is responsible for an increase in Revap in patients with dry eye. Both of these ideas have never been proven. The purpose of the current studies was to test these ideas. Revap was measured in vitro gravimetrically. Lipid spreading was measured using Raman spectroscopy and microscopy. The influence of the following surface films on the Revap of the sub phase of physiologically …

Decreasing Unintentional Pregnancies For Tennesseans, Paula M. Todd

Electronic Theses and Dissertations

In 2018, 49% of all pregnancies in the United States were unintended, with women with a lower- income status being five times more likely to experience an unplanned pregnancy. Tennessee has a high rate of unintended pregnancies, particularly among the uninsured, low-income, and rural teen populations; some 22% of these unintended pregnancies end in abortion. Oral or transdermal contraceptives that are affordable and accessible for women of childbearing age can reduce unintentional pregnancies. The addressed gap in clinical practice was that contraceptives are not currently available over the counter in Tennessee pharmacies without a prescription, which necessitates a costly medical …

Machine Learning Applied To Colloidal Properties Of Perfluorocarbon Nanoemulsions For Imaging In Ards/Ali, Marco Hosfeld

Electronic Theses and Dissertations

Acute Respiratory distress Syndrome (ARDS) and Acute Lung Injury (ALI) are inflammatory lung pathologies consisting of non-hydrostatic pulmonary edema leading to hypoxia and impaired gas exchange in the lungs. ARDS/ALI is both difficult to study and treat as it is not in itself a specific pathology but rather a syndrome consisting of many pathologies that vary case by case. It is, however, consistently characterized by an explosive acute inflammatory response in the lung parenchyma leading to hypoxia. Although time has seen to an increase in the understanding of ARDS/ALI, the mortality rate remains in the range of 30-50%. For these …

Identifying The Cardiovascular Effects Of Multiple Pollutants., Katlyn Elizabeth Mcgraw

Electronic Theses and Dissertations

Cardiovascular disease (CVD) is the leading cause of death from environmental exposures. Although exposure to PM_2.5 is an established risk factor for CVD, the contribution of other hazardous pollutant exposure to CVD is less clear. Overall, this work aimed to examine the effect of pollutants with lesser documented effects on cardiovascular disease using a multi-pronged approach to exposure assessment. The three aims were to examine the relationship between county-level toxic chemical releases and CVD mortality in the contiguous United States between 2002 and 2012, to assess the relationship between individual-level VOC metabolites and vascular function, and to build multipollutant …

Heterocyclic Amines And Arylamine N-Acetyltransferase 2 Polymorphism In Pathogenesis Of Insulin Resistance., Kennedy M. Walls

Electronic Theses and Dissertations

Heterocyclic amines (HCAs) are formed when cooking meats at high temperatures or for long periods of time, and their major metabolic pathway includes hepatic N‑hydroxylation by CYP1A2 followed by O-acetylation by N-acetyltransferase 2 (NAT2). NAT2 is a highly polymorphic gene involved in metabolism of drugs and xenobiotics, and its single nucleotide polymorphisms (SNPs) produce phenotypes characterized as slow, intermediate, or rapid acetylator. Recent studies have documented associations between HCAs and insulin resistance and between certain NAT2 phenotypes and insulin resistance. In this study, we demonstrated that NAT2 activity and exposure to certain HCAs may alter cellular glucose …

Identification And Structural Characterization Functional Motifs In The Porphyromonas Gingivalis Mfa1 Short Fimbria., Mohammad K. Roky

Electronic Theses and Dissertations

Porphyromonas gingivalis is a causative agent of periodontal disease, initially colonizes the oral cavity by adhering to commensal streptococci. Adherence requires the interaction of the minor fimbrial protein (Mfa1) of P. gingivalis with streptococcal antigen I/II (Ag I/II). A peptide derived from Ag I/II peptide has been well characterized and shown to significantly reduce P. gingivalis colonization and bone loss in vivo, suggesting that this interaction represents a potential target for therapeutic intervention. However, the functional motifs of Mfa1 involved in the interaction with Ag I/II remain uncharacterized. A series of N- and C-terminal peptide fragments of Mfa1 were …

Arachidin 3 Modulation Of Lipid Metabolism In Rotavirus Infections, Stormey Wisdom

Electronic Theses and Dissertations

Rotavirus (RV) can cause severe and deadly gastroenteritis in young children, infants, and immunocompromised individuals. Previous studies have shown that arachidin 3 (A3) inhibits RV replication, and that RV replication is dependent on the presence of lipids. This study investigated the alteration of lipid metabolism by A3 in RV infected HT29.f8 cells. A decrease in the RV regulation of lipid biosynthesis genes was observed with the addition of A3 using qRT-PCR. Also, immunofluorescent and histochemical staining for neutral fats, a major component of cellular lipid droplets, revealed an increased accumulation with both RV and RV+A3 when compared to no virus …

Synthesis, Characterization, And Evaluation Of Metal Complexes With Cancer Selective Anti-Proliferative Effects And Hydrogen Evolution Catalytic Properties., Nicholas Vishnosky

Electronic Theses and Dissertations

Bis-thiosemicarbazones (BTSC) and their metal chelates have properties that are useful in several different scientific fields. These systems have already received attention in major fields of biology and engineering. Hydrogen evolution reaction (HER) catalysts need to be cheap and operate under minimal overpotentials with a long lifetime. The treatment of cancer requires, novel agents that have potent cytotoxic activity against cancer cells while displaying minimal side effects. In this dissertation the modular synthesis of these bis-thiosemicarbazone systems is utilized to regulate the redox chemistry for employment in the desired sector of chemistry. The ligand and metal chelates synthesized were characterized …

Development Of A Lectin-Fc Fusion Protein With Antiviral And Anti-Cancer Activity., Matthew William Dent

Electronic Theses and Dissertations

This thesis describes the development of a novel lectin-Fc fusion protein and its antiviral and anti-cancer activity. The molecule, Avaren-Fc (AvFc), is a fusion of a variant of the actinomycete lectin actinohivin (Avaren) and the Fc region of human IgG1, and is selective for the terminal α1,2-mannose residues found at the ends of high-mannose-type glycans that can be found on the surface of certain heavily glycosylated viruses and cancer cells. Here, AvFc was found to be able to neutralize simian immunodeficiency virus as well as Hepatitis C virus with nanomolar IC₅₀ values. Furthermore, AvFc recognizes a number of cell …

Photoassisted Synthesis Of Complex Polyheterocycles Via Esipt-Driven Dearomative Intramolecular Cycloadditions, Dmitry Kuznetsov

Electronic Theses and Dissertations

This research is focused on the development of novel photoassisted synthetic methodologies that provide straightforward access to complex and diverse libraries of polyheterocycles from modularly assembled precursors. All methods are based on the dearomative cycloadditions between two components: (i) o-azaxylylenes, generated by the excited-state intramolecular proton transfer, and (ii) tethered arene groups.

We have demonstrated the synthetic utility of four new photoinduced processes that yield complex products amenable for post-photochemical modifications:

• [4+4] Cycloaddition of o-azaxylylenes to 1,3,4-oxadiazoles with subsequent dinitrogen extrusion. This reaction furnishes compounds outfitted with epoxide fragments, which undergo ring-openings with various nucleophiles; furthermore, the oxidized products …

A Complete Approach To Predict Biodistribution Of Nanomaterials Within Animal Species From In-Vitro Data, Edward Price

Electronic Theses and Dissertations

Smart drug-design for antibody and nanomaterial-based therapies allows for optimization of drug efficacy and more efficient early-stage pre-clinical trials. The ideal drug must display maximum efficacy at target tissue sites, but to track and predict distribution to these sites, one must have a mechanistic understanding of the kinetics involved with the individual cells of the tissue itself. This process can be tracked through biological simulations coupled with in-vitro approaches, which result in a rapid and efficient in-depth understanding of drug transport within tissue vasculature and cellular environment. As a result, it becomes possible to predict drug biodistribution within live animal …

The Study Of Alcoholic Liver Diseases, Seun Emmanuel Owoseni

Electronic Theses and Dissertations

Excessive alcohol consumption is the primary contributing factor in the development of alcoholic liver diseases (ALD). Nicotine contained in tobacco is a major addictive alkaloid, which enhances the effects of ALDs. The major enzyme involved in nicotine metabolism is cytochrome P450 2A5 (CYP2A5) which is produced in the liver. Alcohol can stimulate the CYP2A5 enzyme. We utilized cyp2a5-/- knockout mice in this research to examine the effects of CYP2A5.

The cyp2a5-/- mice and wild-type (WT) mice were fed liquid ethanol diet with or without nicotine to induce ALD. Nicotine enhancing effects on ALD were observed in WT mice but not …

Macromolecule Loading On Plga Particles Through Surface Adsorption, Yiwei Wang

Electronic Theses and Dissertations

The advent of biotherapeutics have impacted the ways in which diseases are treated. In many instances development of recombinant proteins and oligonucleotides into therapeutics are slowed by poor stability of the candidate drugs. Progress has been made in using polymeric particles as carriers of macromolecule drugs. Historically the method is to encapsulate biological drugs into spherical polymeric matrices. Owing to its biocompatible and biodegradable nature, poly (d,l-lactic-co-glycolic acid) (PLGA) has been used extensively in formulating biological drugs into nano- and micro-sized particles. The development of PLGA biologic formulations, however, has been hampered by matrix acidification; the hydrolysis of the polymer …

The N-Terminal Methyltransferase Homologs Nrmt1 And Nrmt2 Exhibit Novel Regulation Of Activity Through Heterotrimer Formation., Jon David Faughn

Electronic Theses and Dissertations

Protein, DNA, and RNA methyltransferases have an ever-expanding list of novel substrates and catalytic activities. Even within families and between homologs, it is becoming clear the intricacies of methyltransferase specificity and regulation are far more diverse than originally thought. In addition to specific substrates and distinct methylation levels, methyltransferase activity can be altered through formation of complexes with close homologs. This work involves the N-terminal methyltransferase homologs NRMT1 and NRMT2. NRMT1 is a ubiquitously expressed distributive trimethylase. NRMT2 is a monomethylase expressed at low levels and in a tissue-specific manner. They are both nuclear methyltransferases with overlapping target consensus sequences …

Alpha-Amino Methylation And Acetylation Are Novel Regulators Of Myl9 Function., Christopher David Nevitt

Electronic Theses and Dissertations

Dysregulation of alpha-amino post-translational modifications (Nα-PTMs) is found in multiple cancers and developmental disorders. However, the exact roles Nα-PTMs play in regulating protein function remain poorly understood. I sought to clarify the role of Nα-methylation and Nα-acetylation in the regulation of Myosin Regulatory Light Chain 9 (MYL9). MYL9 is a key cytoskeletal regulator and transcription factor and is the first protein confirmed to undergo both Nα-methylation and Nα-acetylation. Through this work I revealed novel regulatory features of MYL9, while also presenting a framework by which to understand the coordinated regulation of proteins by Nα-methylation and Nα-acetylation. Nα-PTM selective mutants of …

Synthesis Of 2,4,6-Substituted Pyrrolo[2,3-D]Pyrimidines As Potential Anticancer Agents, Si Yang

Electronic Theses and Dissertations

This thesis mainly focuses on the introduction of the background and work have been done in the areas of antifolates development, such as folate function, its three uptake mechanisms inside human cells, antifolates’ role in chemotherapy, et. al. In addition, the Structure-Activity-Relationship design rationale for the series of antifolates will also be discussed. Nevertheless, the details of synthesizing these pyrrolo[2,3-d]pyrimidines as potential antifolates have been described, including chemistry reviews on the pyrrolo[2,3-d]pyrimidine scaffold, and the challenges encountered and the solutions how to solve or improve in order to achieve better yield.

Magnetic Field-Induced Intramolecular Cyclization As A Trigger For Nanoparticle-Based Delivery Systems., Sara Katherine Biladeau

Electronic Theses and Dissertations

Magnetic nanoparticles (MNPs) are used in a variety of applications, including as agents for magnetic resonance imaging, generation of local hyperthermia, and as platforms for drug delivery. Iron-based MNPs are often coated with a shell, such as silica or gold, to increase biocompatibility for drug delivery applications. Many MNPs used for cancer therapy rely on either an internal trigger, such as a difference in pH, or an external trigger, such as light or an alternating magnetic field (AMF), to cause release of a payload, typically a chemotherapeutic drug. Internal triggers are appealing because drug release can be targeted to a …

Sphingolipids In Models Of Kidney Disease And Injury., Tess V. Dupre

Electronic Theses and Dissertations

Acute kidney injury (AKI), resulting from cisplatin, remains an obstacle in the treatment of cancer. Cisplatin-induced AKI involves cell death pathways regulated by sphingolipids such as ceramide and glucosylceramide. Results indicate that cisplatin-treated mice had increased levels of ceramide and hexosylceramide. Pre-treatment of mice with inhibitors of ceramide synthesis prevented accumulation of ceramide and hexosylceramide in the renal cortex and attenuated cisplatin-induced AKI. To determine the role of ceramide metabolism to hexosylceramides in kidney injury, we treated mice with an inhibitor of glycosphingolipid synthesis. Inhibition of glycosphingolipid synthesis attenuated the accumulation of the hexosylceramide and exacerbated ceramide accumulation in the …

Discovery Of Pyrimidine-Based Heterocycles As Single Agents With Combination Chemotherapy Potential And As Inhibitors Of Purine Nucleotide Biosynthesis For The Treatment Of Cancer, Rishabh Mohan

Electronic Theses and Dissertations

This dissertation describes the design, synthesis and biological evaluation of monocyclic and bicyclic pyrimidine-base heterocycles as single agents with combination chemotherapy potential having both antiangiogenic effects and cytotoxic effects. This dissertation also describes selective tumor targeting with 5-substituted pyrrolo[2,3-d]pyrimidines analogs with heteroatom bridge substitution as GARFTase inhibitors.

The work in this dissertation is centered on identifying structural features that are necessary for inhibition of tubulin polymerization as well as for inhibition of one or more of the receptor tyrosine kinases (RTKs)- vascular endothelial growth factor receptor-2 (VEGFR2), platelet derived growth factor receptor-β (PDGFRβ) and epidermal growth factor receptor …