The Effects Of Increasing Positively Charged Metal Ions Within Synovial Fluid, Kandisi Anyabwile

Williams Honors College, Honors Research Projects

Osteoarthritis is a degenerative joint disease that affects 10% of men and 13% of women over age of 60. It is the degradation of the cartilage between two bones; obesity, age, overuse, or injury are major contributors to the development of this disease. The joint is incapsulated by the synovial sac filled with a viscous solution that aids in lubrication referred to as synovial fluid. If the synovial sac is ruptured due to injury, positive ions (K⁺, Na⁺, Ca²⁺, and Fe³⁺) may affect viscoelastic properties within the sac. The purpose of this …

The Effect Of Cxcl12 Ligand On Internalization And Dimerization Of Cxcr4 Receptors In Live Cells, Loga Iyer

Williams Honors College, Honors Research Projects

The primary objective of this project was to determine the effect of CXCL12 ligand binding on the CXCR4 receptor, specifically, how it would impact receptor internalization and dimerization. The CXCL12 ligand derives from the stromal cell-derived alpha family [8]. The CXCR4 receptors, known as C-X-C chemokine receptor type 4 play an essential role in controlling cell proliferation. When misregulated, these receptors can drive tumorigenesis and are thus important targets of cancer therapy. These G protein-coupled receptors stimulate a cascade of signaling pathways in specific tissues [1]. These pathways include the positive transcriptional control of CXCR4 via the Nuclear Respiratory Factor-1 …

The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes

Honors Theses

The internal recycling phosphorus in freshwater lake bottom sediments represents a significant source of hypolimnetic phosphorus (P) release for many of Maine’s lakes. In summer months, Maine lakes often thermally stratify and the lake hypolimnion develops anoxia, leading to a reduction in redox potential at the sediment-water interface. These reducing conditions facilitate the reductive dissolution of ferric iron, and, since phosphorus is often present in freshwater lake sediments as solid FeOOH-PO₄ complexes, results in release of soluble phosphorus into the water column. Our current study presents field and laboratory data from sediment fractionation extractions designed to quantify concentrations of …

Use Of Small Molecule Fanconi Anemia Pathway Inhibitors As Sensitizing Agents To Laromustine., Sam W. Marchant

Honors Theses

Laromustine is an experimental chemotherapeutic sulfonyl hydrazine prodrug shown in clinical trials to be effective against acute myeloid leukemia. The mechanism of action of laromustine involves interstrand crosslinking, via chloroethylation, and enzyme inhibition, caused by carbamoylation. The work described herein aims to investigate whether inhibition of the replication-dependent interstrand crosslink repair Fanconi Anemia pathway further sensitizes cells to laromustine. By measuring metabolic activity immediately after drug exposure, we find laromustine to be equally as cytotoxic towards Fanconi Anemia deficient and wild type cells. However, through clonogenic assays we show Fanconi Anemia mutations sensitize cells to laromustine’s anti-proliferative effect. Furthermore, we …

Understanding The Relationship Between Local Environmental Changes And The Function Of The Ph Low Insertion Peptide, Violetta Burns Casamayor

Graduate Theses, Dissertations, and Problem Reports

Cancer is the second leading cause of death in the US with over 1.7 million new cases each year. Current cancer treatments tend to also target healthy tissues due to similarities with cancerous ones, resulting in acute side effects. Early detection is the best approach towards defeating cancer, however, modern imaging techniques require sizeable samples, often implying a late stage in the disease. One common attribute of tumors is their acidic microenvironment, which can be taken advantage of.

The pH Low Insertion Peptide (pHLIP) is a membrane-active peptide that can take advantage of the acidic microenvironment surrounding cancer cells. pHLIP …

Role Of Rna Helicases In The Drosophila Germline, Patrick Blatt

Legacy Theses & Dissertations (2009 - 2024)

Gametogenesis, the process of creating egg or sperm, is required for launching successive generations of sexually reproducing organisms. The developmental milestones that occur during gamete production have been studied for decades and are of critical interest to gain insight to conserved features of human fertility. Drosophila has been used for over a century as an efficient research model and remains pivotal in uncovering fundamental biological paradigms. During Drosophila egg production, or oogenesis, several developmental transitions must be traversed to ensure completion of oogenesis including: Germline Stem Cell (GSC) maintenance and differentiation, mitotic and meiotic cell divisions, and production of maternally …

Host Factors Affecting Group Ii Intron Retrotransposition, Justin Michael Waldern

Legacy Theses & Dissertations (2009 - 2024)

Group II introns are self-splicing mobile elements that are thought to be the evolutionary ancestors of eukaryotic retrotransposons, the spliceosome, and spliceosomal introns. Yet, little is known about how group II introns have coevolved within their native hosts or about the corresponding host biology.Using the Ll.LtrB intron in its native host, Lactococcus lactis, I first sought to identify host factors that influence retrotransposition. Since retrotransposition can be costly to the host organism, group II introns must achieve a delicate balance between self-proliferation and host preservation. By utilizing the native host organism, my goal was to unearth retrotransposition-related mechanisms that have …

Kinetic Characterization Of Two C-Family Polymerases From The Gram-Positive Bacterium Staphylococcus Aureus, Sean P. Fagan

Legacy Theses & Dissertations (2009 - 2024)

In this dissertation, I review the fundamental processes and mechanisms for bacterial DNA replication, especially the mechanisms employed by high-fidelity DNA polymerases to replicate the genome. Unlike the prototypical bacterial system from Escherichia coli which uses a single C-family polymerase, DNA polymerase IIIα (Pol IIIα), to replicate the genome, low-GC content Gram-positive bacteria utilize two essential C-family polymerases, PolC and DnaE. PolC and DnaE work cooperatively to replicate the genome, with DnaE initiating synthesis from RNA-primers and PolC performing the bulk synthesis. Although atomic structures of both PolC and Pol IIIα are available, detailed pre-steady state kinetic analysis of the …

Development Of Chemical Methods For Oligonucleotide Purification, Paramagnetic Labeling And Synthesis Of Dna-Based Advanced Materials, Muhan He

Legacy Theses & Dissertations (2009 - 2024)

This thesis describes a chemical method for alternative oligonucleotide purification that is non-chromatographic and gel-free and allows to routinely synthesize and purify long functional RNA strands. The purification of long RNAs is based on the bio-orthogonal inverse electron demand Diels-Alder (IEDDA) chemistry between trans-cyclooctene (TCO) and tetrazine (Tz). Target oligonucleotide strands are selectively tagged with Tz and can be captured and purified from the failure sequences with immobilized TCO. RNA strands are synthesized on solid support through a photolabile linker to avoid the loss of Tz tag. Purity of the isolated oligonucleotides was evaluated using gel electrophoresis, HPLC and mass …

Missense Mutations In The Gamma Crystallins And Mechanisms Of Lens Opacity, Wenjuan Hou

Legacy Theses & Dissertations (2009 - 2024)

Cataract, or clouding of the ocular lens, among the most common types of eye diseases, is the leading cause of blindness worldwide. With the opacity or clouding of the lens, light incident on the lens is scattered rather than being transmitted and is thus prevented from focusing on the retina. The lens becomes cataractous due to a large number of reasons, among which aging and genetic mutations are two of the most common factors. Clouding of the center of the lens or nuclear opacity, is the most frequently observed type of age-onset cataract, as well as inherited, congenital cataract [1, …

The Phosphodiesterase, Rv0805, Is An Unheralded Component Of Tb Complex Mycobacterial Physiology In And Beyond Camp Homeostasis, James R. Mcdowell

Legacy Theses & Dissertations (2009 - 2024)

Phosphodiesterases (PDEs) are integral components of 3’,5’-cyclic adenosine monophosphate (cAMP) signaling pathways by degrading cAMP to modulate the concentration, duration, and localization of the cAMP signal which maintains the specificity of cAMP pathways. The human pathogen, Mycobacterium tuberculosis (Mtb) has a unique cAMP network architecture with at least 15 adenylyl cyclases (ACs) that generate cAMP, but only one characterized PDE, Rv0805, which is found exclusively in pathogenic mycobacteria. Rv0805 can influence Mtb cAMP levels but the absence of Rv0805 orthologs in non-pathogenic mycobacteria and apparent separation of Rv0805 from cAMP directed roles led to numerous questions surrounding PDE function in …

Retrotransposon-Mediated Transduction Of An Environmental Cue To Regulate Centrosome Fate, Shawn Patrick Murphy

Legacy Theses & Dissertations (2009 - 2024)

In 1969, the enrichment of mobile element repeat sequences led Britton and Davidson to propose the hypothesis that gene expression in higher eukaryotes is regulated through the exaptation of mobile elements. In this work, I have explored the hypothesis that mobile elements can also be harnessed by the host to regulate asymmetric cell division, thereby determining cell fate. Retrotransposons are ubiquitous eukaryotic mobile elements that transpose through an RNA intermediate. They are often active in cell types that divide asymmetrically to yield daughter cells with different fates, such as embryonic stem cells, germline stem cells, neuronal stem cells and the …

Pre-Steady-State Kinetic Characterization Of An Antibiotic-Resistant Mutation Of Staphylococcus Aureus Polc, Rachel Alice Nelson

Legacy Theses & Dissertations (2009 - 2024)

In this dissertation I provide a pre-steady-state kinetic characterization of an antibiotic-resistant mutant of a Staphylococcus aureus DNA polymerase. Staphylococcus aureus is one of the most common causes of infections in humans, and is widely known for its ability to acquire resistance to most antibiotics. Staphylococci infections pose a significant burden to the healthcare system and increase mortality, as more than 95% of Methicillin-Resistant S. aureus (MRSA) infections do not respond to first-line antibiotics. The limited treatment options for Staphylococci infections underscores the need for novel, alternative strategies. In this thesis, I discuss 6-anilinouracils (6-AU), a family of potent dGTP …

Identification Of Ires Activity In Cellular Mrnas And Viral Rna Using A Circular Rna Construct, Priyanka Sehta

Legacy Theses & Dissertations (2009 - 2024)

Translation initiation is a critical step in the process of protein synthesis. The canonical way of translation initiation involves ribosomes being recruited to the 7-methyl guanosine cap present at the 5’end of the untranslated region (5’ UTR) of the RNAs. However, viral RNAs and some cellular mRNAs lack this 5’ cap structure and thus deploy an alternate non-canonical translation initiation mechanism. In non-canonical translation initiation, ribosome recruitment is facilitated by the RNA secondary structures called Internal Ribosome Entry Site (IRES) present most often in the 5’ UTR. To measure IRES-mediated translation, the dual luciferase assay has been the gold standard. …

Study Of Primary Cilium Structure And Intraflagellar Transport, Shufeng Sun

Legacy Theses & Dissertations (2009 - 2024)

Primary cilia are hair-like protrusions that stem from the basal bodies in the cytoplasm and extend into the extracellular space to sense signals. Intraflagellar transport (IFT) functions to transport cargo molecules into and out of the ciliary compartment to assemble, maintain, and disassemble the cilia. Accurate knowledge of the three-dimensional (3D) structure of primary cilia and precise details of the IFT profile is the foundation for understanding the sensory functions of primary cilia. This work covers three aspects of primary cilia. Firstly, we obtained and analyzed the overall 3D architecture of the complete primary cilia axoneme region using serial section …

Development Of Linked-Domain Protein Inhibitors Of The E2-Conjugating Enzyme Ube2d, Anneroos E. Nederstigt

University of the Pacific Theses and Dissertations

In most eukaryotic organisms, the ubiquitination pathway is one of the most important and versatile signaling systems in use. It is integral to processes such as protein degradation and homeostasis, DNA repair cell cycle regulation, signaling and regulation, epigenetics, and many more. Ubiquitin (Ub) is a short polypeptide of 8.6 kDa, 76 residues that functions as a reversible post-translation modification (PTM). It furthermore contains 7 different lysine residues (K6, K11, K27, K29, K33, K48, K63), all of which can form isopeptide linkages with one another to link individual Ub moieties to form unique polyUb chains onto substrates. The type of …

On The Structure And Function Of Mitochondrial Uncoupling Proteins: The Case Of Ucp2, Afshan Ardalan

Theses and Dissertations (Comprehensive)

Uncoupling proteins (UCPs) are regulated proton transporters of the mitochondrial inner membrane. UCP-mediated proton leak negatively impacts the rate of ATP synthesis. Despite the importance of their physiological role(s) in certain tissues, molecular aspects of UCPs’ structure-function relationships are not fully understood. The current study explores the tertiary and quaternary structure of UCP2, as well as its proton transport mechanism in lipid membranes. The proteins were expressed in the E. coli inner membrane, purified and reconstituted into liposomes. Proteins were characterized by semi-native SDS-PAGE. Circular dichroism spectroscopy (CD) and fluorescence quenching assays were utilized to study the conformation of proteins …

Physiological Impacts Of Lampricides On Invasive Sea Lamprey (Petromyzon Marinus) And Non-Target Fishes, Razvan, Adrian Ionescu

Theses and Dissertations (Comprehensive)

Parasitic sea lamprey (Petromyzon marinus) ingest large quantities of blood from fishes using their oral disc and rasping tongue, most often killing the host. In the early 1900s, sea lamprey invaded the Laurentian Great Lakes, decimating sport, commercial and culturally significant fisheries. Since the early 1960s, chemical control using the lampricides 3- trifluoromethyl-4-nitrophenol (TFM) and niclosamide have helped to reduce sea lamprey populations by 90%. Lampricides are applied to larval lamprey nursery streams targeting many generations of lamprey at once. However, there is concern about the potential adverse effects of lampricides on other fishes, particularly vulnerable lake sturgeon (Acipenser fulvescens) …

A Bioinformatic Analysis Of The Biosynthesis Of Carotenoids In The Copepod Tigriopus Californicus, Anchalya Balasubramaniam

Theses and Dissertations (Comprehensive)

Abstract

Biological pigments, also called biochromes, are coloured compounds which are displayed by a variety of life forms, including animals, due to selective colour absorption. The combination of light absorption and reflection enables each pigment to portray a distinct colour which results in the broad spectrum of colours we observe in our surroundings. Carotenoids are a large group of yellow, orange, and red biological pigments found in living organisms. Our current biomolecular knowledge of carotenoids is heavily derived from studying the pathway in photosynthetic prokaryotes, bacteria, fungi, and plants. Carotenoid pigments are exceptionally multifunctional as they act as photo-protectors against …

Marine Phytoplankton Functional Types Exhibit Diverse Responses To Thermal Change, S. I. Anderson, A. D. Barton, Sophie Clayton, S. Dutkiewicz, T. A. Rynearson

OES Faculty Publications

Marine phytoplankton generate half of global primary production, making them essential to ecosystem functioning and biogeochemical cycling. Though phytoplankton are phylogenetically diverse, studies rarely designate unique thermal traits to different taxa, resulting in coarse representations of phytoplankton thermal responses. Here we assessed phytoplankton functional responses to temperature using empirically derived thermal growth rates from four principal contributors to marine productivity: diatoms, dinoflagellates, cyanobacteria, and coccolithophores. Using modeled sea surface temperatures for 1950-1970 and 2080-2100, we explored potential alterations to each group's growth rates and geographical distribution under a future climate change scenario. Contrary to the commonly applied Eppley formulation, our …

Exploring The Connection Between The Spontaneous Regression Seen In Neuroblastomas, Hypertumors, And Reactive Oxygen Species, Shahad Musa, Manitha Mulpuru

Auctus: The Journal of Undergraduate Research and Creative Scholarship

Peto’s Paradox is defined as the lack of correlation between larger animals and cancer risk. Under the assumption that all cells have equal risk of becoming cancerous, larger animals should have greater rates of cancer. However, the inverse is true. Determining the cause of this variation may allow a supplemental approach to cancer treatment. A combination of two reasons may account for this correlation including hypertumors and metabolism. Hypertumors, or cheater cells, are hypothesized to suppress cancer growth through spontaneous autophagic degradation and overexpression of the RAS g-protein. Both of these characteristics are exhibited in Neuroblastomas. An anticancer drug used …

Fxr Agonists Induce Distinct H-12 Structural States, Vikash Kumar

Graduate Student Theses, Dissertations, & Professional Papers

The nuclear receptor ligand-binding domain (LBD) is a highly dynamic entity. The FXR LBD shows multiple low-energy conformational states of the activation function-2 (AF-2) coregulator binding surface upon ligand binding, indicating the complexity of FXR activation. However, it is unknown how ligand binding leads to different conformational states within the AF-2 region centered on helix 12 (H-12) of the LBD. Here we observe the conformation of the coregulator binding surface (H-12 specifically) of FXR upon ligand binding in solution using fluorine-19 (19F) nuclear magnetic resonance (NMR) and simulations of this surface using molecular dynamics. Fluorescence anisotropy of fluorescein-labeled coregulator peptides …

In Silico And In Vitro Screening Of Newly Designed Compounds Against Coxsackivirus A16 And Enterovirus A71, Amita Sripattaraphan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Outbreaks of hand, foot, and mouth disease (HFMD) occur around the world. It is caused by the Coxsackievirus-A16 (CV-A16) and Enterovirus-A71 (EV-A71) that belong to the Enterovirus genus. Unfortunately, neither an anti-HFMD drug nor a vaccine is currently available. Rupintrivir, one of the drug candidates for HFMD treatment, has been attractive for the development of its analogs with broad biological activities. This drug is an inhibitor for 3C protease of CV-A16 and EV-A71, an enzyme that plays a crucial role in the viral replication process. ). In the present study, we focused on designing 50 novel rupintrivir analogs against CV-A16 …

Functional Characterization Of Rice Malate Synthase In Arabidopsis Responding To Salt Stress, Supisara Thanabut

Chulalongkorn University Theses and Dissertations (Chula ETD)

Salt stress is one of the major abiotic stresses that seriously limit plant growth and development and can lead to a significant reduction in crop yield, especially rice. Salt stress affects plants via ionic toxicity and osmotic stress. Osmotic stress results in a reduction of water absorption ability. Ionic toxicity causes Na+ toxicity, which disrupts photosynthesis, protein synthesis, and enzyme activity. The previous study of KDML105 rice transcriptome profile and qRT-PCR revealed that rice malate synthase (OsMS) encoding malate synthase, which is one of the key enzymes in glyoxylate cycle was up-regulated under salt stress, so OsMS may involve in …

The F-Box Protein Fbw7 Negatively Regulates The Stability Of Erk3 Protein, Nicole Walters

Browse all Theses and Dissertations

Extracellular signal-regulated kinase 3 (ERK3) is a member of the atypical mitogen-activated protein kinase (MAPK) subfamily, whose members have been shown to play important roles in a number of cellular processes including proliferation, differentiation, migration, and apoptosis. While signals regulating ERK3 kinase activity remain unclear, ERK3 is known to be an unstable protein with function tightly regulated via ubiquitination and proteasomal turnover. The deubiquitinating enzyme USP20 has been shown to regulate ERK3 by stabilizing the kinase, but presently, no destabilizing ubiquitin ligases have been identified. The SKP1-CUL1-F-box protein (SCF) E3 ligases are a subfamily of ubiquitin E3 ligases composed of …

Quantitated Effects Of Nutritional Supplementation On Exercise Induced Sweat, Andrew Blake Austin Browder

Browse all Theses and Dissertations

Discovery studies have identified many metabolites contained in human sweat. However, quantitative analysis of the sweat metabolome content remains mostly unknown. Furthermore several attributes, including rate, have been defined to affect sweat metabolite content, while other effectors, like diet, remain unknown. This study works to quantitatively define the metabolite impact caused by nutritional supplementation. To better understand the effect diet plays, a LC-MS method was developed focusing on improving resolution and peak width. While the literature provided examples of how diet affected sweat metabolite concentrations, the long-term effects of diet have not been explored. The experiment described here attempts to …

Microsatellites And Their Association With Break Induced Replication, French J. Damewood Iv

Browse all Theses and Dissertations

To study microsatellites instability and their repair pathways a dual fluorescent (DF2) and selectable (ganciclovir sensitive/ thymidine kinase (TK) expressing) cell system was assayed using replication fork stalling agents hydroxyurea and telomestatin. These cell lines carried ectopically integrated microsatellites derived from the Dystrophia Myotonica Protein Kinase (DMPK) gene ((CTG)102 microsatellite), or an 88 bp polypurine/ polypyrimidine (Pu/Py) repeat from the PKD-1 locus, inserted into a FLP recombinase target site. These microsatellites form non-B DNA structures in -vivo and in-vitro causing replication fork stalling and double strand breaks. DF2 myc (CTG)102 -TK cells treated with hydroxyurea were assayed for mutagenesis of …

Potential Drug Treatment For Duchenne Muscular Dystrophy Which Could Be Through Upregulation Of Lipin1, Rajsi Y. Thaker

Browse all Theses and Dissertations

Duchenne muscular dystrophy (DMD) is a genetic disorder leading to progressive muscle degeneration and weakness due to mutation in dystrophin gene, which is very important for maintaining muscle membrane integrity. Dystrophin is the largest gene in the human genome therefore more prone to mutation. There is currently no cure for DMD. Our lab recently found that Lipin1 deficient myofibers showed upregulation of necroptosis correlated with the loss of muscle membrane integrity. Our primary approach for ameliorating dystrophic phenotype in DMD is through reduction of necroptosis using drugs which can potentially upregulate Lipin1 expression. In this study, we identified two drugs …

Transcriptional Programming By Thyroid Hormone Receptor Beta Maintains Normal Cell Identity And Suppresses Tumor Growth, Noelle Elizabeth Gillis

Graduate College Dissertations and Theses

The overall incidence of thyroid cancer has more than tripled over the past several decades, as has aggressive disease and mortality. The direct relationship between thyroid disease, thyroid hormone levels, and development of thyroid cancer is incomplete. Recent meta-analyses have indicated a higher risk of thyroid cancer for patients with thyroid diseases that reflect an altered thyroid-pituitary signaling axis, which can have profound impacts on the physiology of the thyroid gland. These largely unanswered questions regarding altered thyroid hormone signaling and its consequences for thyroid tumor growth present a significant clinical challenge. This dilemma may come from a lack of …

Designer Biologics Composed Of Hepatocyte Growth Factor, Fibroblast Growth Factor 2 And Immunoglobulin G For Treatment Of Acute Myocardial Infarction, Benjamin Liebman

Graduate College Dissertations and Theses

ABSTRACT Coronary artery disease leading to myocardial infarction (a.k.a. MI, heart attack) is one of the leading causes of death globally. Each year an estimated 605,000 Americans suffer a heart attack, which equates to one MI every 40 seconds. As such, MI represents one of the largest health burdens to society. The current standard of care is revascularization therapy achieved by fibrinolytics and Percutaneous Coronary Intervention (PCI); both of which re-open occluded proximal arteries to restore blood flow to the affected areas. Despite revascularization therapy, 30-50% of patients exhibit a form of reperfusion injury termed “no/low-reflow” in which the blood …