Life Sciences Commons^™

Gestational Vulnerability To Ozone Air Pollution - A Placental Story, Vishnupriya Alavala, Sarah Brent, Russell Hunter, Matthew J. Campen, Andrew Ottens

Undergraduate Research Posters

About 99% of the global population resides in areas with air pollution surpassing World Health Organization standards. Air pollution is associated with adverse neonatal health outcomes such as low fetal birth weight and an increased risk for maternal pre-eclampsia. A particularly reactive air pollutant is ozone, which forms reactive oxygen species that induce cellular damage. Research exists on the dispersion of reactive oxygen species through the bloodstream leading to fetal vulnerability during pregnancy, specifically via the placenta. Yet, placental and fetal development is a temporal process with varied susceptibility to negative gestational outcomes.

To addressing this gap, our laboratory utilized …

Treponema Denticola Synthesizes C-Di-Amp And Encodes The Cdaa-Type Diadenylate Cyclase Cdaa, Claire R. O'Brien

Theses and Dissertations

Periodontitis is a form of oral disease characterized by dysbiosis of the oral microbiome, leading to inflammation, bone resorption, and in severe cases, entire tooth loss, affecting 42% of adults in the US. One of the bacteria most associated with periodontal disease progression is Treponema denticola (Td), an oral spirochete which inhabits the mouth in small quantities during health but which can dominate the biofilms that form during periodontal disease. The ability of Td to survive in a disease environment and contribute to the progression of disease requires the use of robust signaling networks. Analysis of Td cultures …

Observing Ceramide Pathway With Ferroptosis Via Mia Paca-2 Cell Treatment With Rsl3, Tazrin Rahman

Auctus: The Journal of Undergraduate Research and Creative Scholarship

Composed of sphingosine and a fatty acid, ceramides are lipid molecules that serve as key metabolic signaling molecules of a sphingolipid pathway. While it acts as a precursor of complex sphingolipids, inducing ceramide generation can cause cell stress leading to subsequent cell death via apoptosis, necrosis, and even mitophagy. With regards to cell death specifically, a novel form of regulated cell death, ferroptosis, has recently been recognized of necrotic nature. Its unique morphological features and distinct properties have been observed over the last several decades; however, the molecular features were not identifiable as pure evidence of cell death, until recently …

The Role Of Irf-1 In Spontaneous Mouse Glioma, Aakash B. Vaidya

Theses and Dissertations

Glioblastoma Multiforme has been shown to be one of the deadliest primary brain cancers. One of the reasons why GBM is so deadly, is a unique immunosuppressive tumor microenvironment that promotes GBM growth and progression. Both astrocyte and microglia have been implicated in immunosuppression. In this study, we explored the role of Interferon Regulatory Factor 1 (IRF-1) in astrocytes and glioma cells on the growth of spontaneous glioma tumors. IRF-1 is regulated by the JAK/STAT pathway and induces expression of Programmed death ligand 1 (PD-L1). PD-L1 downregulates immune responses to glioma. We found that IRF-1 had no effect on spontaneous …

Transcriptional Repressor Protein Based Macrolide Biosensor Development With Improved Sensitivity, Jayani A. Christopher

Graduate Research Posters

Macrolide antibiotics are in high demand for clinical applications. Macrolides are biosynthesized via giant assembly line polyketide synthases (PKS) which are arranged in a modular fashion. Combinatorial biosynthetic methods have been used to produce diversified macrolides by reprograming these modules and modifying tailoring enzymes required for post synthetic modifications. However it is challenging due to the size and complexity of PKSs. To overcome this challenge, new enzymes for macrolide diversification could be obtained by directed evolution where a large number of enzyme variants need to be screened. Therefore it is important to develop high throughput screening methods to identify the …

Influence Of Metal Sleeves In The Accuracy Of Dental Implant Placement Using Guided Implant Surgery, Coleman Adams

Theses and Dissertations

The fabrication of implant surgical guides through stereolithographic 3D printing has become a staple in dental implant guided surgery over the last couple decades. These surgical guides have typically utilized metal sleeves to assist in guidance of the drills during osteotome preparation. The metal sleeves can be costly and potentially cause deviations if improperly placed during post-processing of the guide. This research explored a novel method for the utilization of sleeve-free surgical guides by comparing the dimensional and angulational deviations between the implant guides with and without a metal sleeve. To achieve this goal, two separate aims were pursued. Our …

Computational Analysis And Prediction Of Intrinsic Disorder And Intrinsic Disorder Functions In Proteins, Akila I. Katuwawala

Theses and Dissertations

COMPUTATIONAL ANALYSIS AND PREDICTION OF INTRINSIC DISORDER AND INTRINSIC DISORDER FUNCTIONS IN PROTEINS

By Akila Imesha Katuwawala

A dissertation submitted in partial fulfillment of the requirements for the degree of Engineering, Doctor of Philosophy with a concentration in Computer Science at Virginia Commonwealth University.

Virginia Commonwealth University, 2021

Director: Lukasz Kurgan, Professor, Department of Computer Science

Proteins, as a fundamental class of biomolecules, have been studied from various perspectives over the past two centuries. The traditional notion is that proteins require fixed and stable three-dimensional structures to carry out biological functions. However, there is mounting evidence regarding a “special” class …

Single Molecule Investigations Of Holliday Junction Binding Protein Ruva, Dalton Reed Gibbs

Theses and Dissertations

DNA breaks are inevitable as they mainly occur due to cells’ own reactive oxygen species (ROS). While DNA breaks can be single-stranded or double-stranded, the double-stranded DNA (dsDNA) breaks are more dangerous. If such damage is not repaired, it can lead to genetic instability and serious health issues including cancers. One way dsDNA breaks can be repaired is via a process called homologous recombination (HR), which involves several DNA-binding proteins. Therefore, to have a better insight into the repair mechanism and origin of repair defects, we need a better understanding of how these proteins interact with DNA itself and DNA …

Characterization Of The Dyrk1a Protein-Protein Interaction Network, Varsha Ananthapadmanabhan

Theses and Dissertations

Human Dual specificity tyrosine (Y)-Regulated Kinase 1A (DYRK1A) is a protein kinase encoded by a dosage-dependent gene. An extra copy of DYRK1A contributes to Down syndrome (DS) pathogenesis while loss of one allele causes severe mental retardation and autism. DYRK1A is involved in phosphorylation of several proteins that regulate cell cycle control and tumor suppression. However, the function and regulation of this kinase is not well understood and current knowledge does not fully explain dosage-dependent function of this important kinase. Our previous proteomic studies identified several novel DYRK1A interacting proteins including RNF169, FAM117B, TROAP, LZTS1, LZTS2 and DCAF7. In this …

Characterization Of The Tsc/Dyrk1a Interaction, Supriya Joshi

Theses and Dissertations

The Tuberous sclerosis complex (TSC) includes TSC1, TSC2 and the TBC1D7 subunits that together function as a principal inhibitor of the mTOR protein kinase complex 1 (mTORC1). mTORC1 is a master regulator of cell growth and proliferation that responds to signaling cues such as growth factors and nutrient availability. Proteomic studies in our lab revealed an interaction between the TSC subunits and DYRK1A, a ubiquitous protein kinase encoded by a gene located in the Down syndrome (DS) region on human chr21. In this study, we sought to validate the interaction of the TSC components with DYRK1A and to determine the …

Electrostatic Networks And Mechanisms Of Δph-Dependent Gating In The Human Voltage-Gated Proton Channel Hv1, Ashley L. Bennett

Theses and Dissertations

The structure of the voltage-gated proton (H⁺) channel Hv1 is homologous to the voltage sensor domain (VSD) of tetrameric voltage-gated Na⁺, K⁺ and Ca²⁺ channels (VGCs), but lacks a pore domain and instead forms a homodimer. Similar to other VSD proteins, Hv1 is gated by changes in membrane potential (V), but unlike VGCs, voltage-dependent gating in Hv1 is modulated by changes in the transmembrane pH gradient (DpH = pH_o - pH_i). In Hv1, pH_o or pH_i changes shift the open probability (P_OPEN)-V relation by ~40 mV per …

Targeting Sphingosine Kinase 2 As A Treatment For Cholangiocarcinoma, Anthony D. Stillman

Theses and Dissertations

Cholangiocarcinoma (CCA) has a high mortality rate and its occurrence is rising. This increase prompts the need for improved CCA treatments. Studies have suggested that CCA is highly reliant on the sphingosine-1-phosphate-receptor-2 (S1PR2) and sphingosine kinase 2 (SphK2). Recently, a competitive SphK2 inhibitor, ABC294640, has been approved for clinical trial. ABC294640 has the potential to treat CCA, which is support by a phase I clinical study that was able to temporarily treat a patient suffering from metastasized CCA with ABC294640. To determine the viability of ABC294640 as a treatment for CCA, this study focused on determining the effects of ABC294640 …

Regorafenib Enhances Lethality Of Sildenafil And Curcumin In Colorectal Cancer Cells, Kervin Benjamin Owusu

Theses and Dissertations

In the United States, more than 130,000 people will be diagnosed with colorectal cancer (CRC) each year and an estimated 50,000 people will die from the disease. Standard of care (SOC) therapies for CRC combine multiple cytotoxic chemotherapeutic drugs. These combinations have varying degrees of effectiveness and can often result in significant patient morbidity. For second recurrence patients, the multi-kinase inhibitor, regorafenib, is an approved agent, but is often poorly tolerated at current doses. In the current study, we propose to develop therapeutic regime of combining agents with modest toxicity profiles: curcumin and sildenafil with regorafenib. Using clinically achievable enterohepatic …

Cellular Mechanisms By Which Alcohol Promotes Hiv Protease Inhibitor-Induced Hepatotoxicity, Michael Hinton

Theses and Dissertations

CELLULAR MECHANISMS BY WHICH ALCOHOL PROMOTES HIV PROTEASE INHIBITOR-INDUCED HEPATOTOXICITY

Michael Hinton, B.S.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University

Virginia Commonwealth University, 2019

Major Director: Huiping Zhou

Professor, Department of Microbiology and Immunology

The development of highly-active-antiretroviral therapy(HAART) has allowed management of HIV and extended the lives of those infected. Alcohol abuse, which is very common in HIV-1 infected patients, is one of the most important co-morbid risk factors for liver injury and has been associated with the occurrence of serious metabolic syndrome and subsequent discontinuation …

The Role Of Irf1 In The Brain And In Adaptive Responses Of Astrocytes, Andrew Hoskins

Theses and Dissertations

In neurodegenerative diseases, the CNS becomes inflamed through activation of pathways, including the NF-B pathway. Some of the therapies for those diseases target neuroinflammatory pathways. Here, we explore the mechanisms for the upregulation of a subset of genes following a restimulation of the NF-B pathway. We discover that this upregulation occurs independent of IRF1 expression and type 1 interferon signaling. A knockdown of IRF1 using siRNA and an inhibition of JAK proteins using inhibitor AG490 both had no effect on priming. A secreted factor was found to upregulate the expression of both this subset of genes and genes encoding pro-inflammatory …

Processing Of 3′-Blocked Dna Double-Strand Breaks By Tyrosyl-Dna Phosphodiesterase 1, Artemis And Polynucleotide Kinase/ Phosphatase, Ajinkya S. Kawale

Theses and Dissertations

DNA double-strand breaks (DSBs) containing unligatable termini are potent cytotoxic lesions leading to growth arrest or cell death. The Artemis nuclease and tyrosyl-DNA phosphodiesterase (TDP1) are each capable of resolving protruding 3′-phosphoglycolate (PG) termini of DNA double-strand breaks (DSBs). Consequently, a knockout of Artemis and a knockout/knockdown of TDP1 rendered cells sensitive to the radiomimetic agent neocarzinostatin (NCS), which induces 3′-PG-terminated DSBs. Unexpectedly, however, a knockdown or knockout of TDP1 in Artemis-null cells did not confer any greater sensitivity than either deficiency alone, indicating a strict epistasis between TDP1 and Artemis. Moreover, a deficiency in Artemis, but not TDP1, resulted …

Cellular Inhibitor Of Apoptosis Protein2 – A Critical Regulator Of Neuroinflammation, Debolina Dipankar Biswas

Theses and Dissertations

Inhibitors of apoptosis (IAPs) modulate cell death and play critical role in signal transduction that promotes inflammation. Recently, Smac mimetics, which are IAP antagonists, have attracted attention as novel cancer therapeutics. Cellular Inhibitor of Apoptosis 2 (cIAP2), a member of IAP family, positively affects both NF-κB and MAPK activation in response to many inflammatory stimuli. We observed that the lack of cIAP2 ablates LPS-induced neuroinflammation. Also, cIAP2^-/- macrophages demonstrated diminished antigen presentation potential that could contribute to ablated immunity. In addition to these functions, we have previously reported that cIAP2 also regulates the activation of Interferon Regulatory Factor 1 …

Zebrafish Model Of Mll-Rearranged Acute Myeloid Leukemia, Alex J. Belt

Theses and Dissertations

Acute myeloid leukemia (AML) is the second most common type of leukemia and accounts for 80% of adult acute leukemia cases and is characterized by the accumulation of poorly or undifferentiated myeloid blast cells. Standard treatment includes chemotherapy, which if unsuccessful, is followed by more rigorous chemotherapy as well as stem cell transplantation. Considering most patients are over the age of 45, these more rigorous therapies are not always possible, and as such, new therapies must be developed. Furthermore, AML patients harboring a chromosomal rearrangement involving Multiple Lineage Leukemia (MLL) that results in the expression of an MLL fusion protein …

The Interaction Between Ceramide-1-Phosphate And Group Iva Cytosolic Phospholipase A2 And Its Role In Wound Healing, Patrick Macknight

Theses and Dissertations

The sphingolipid, ceramide-1-phosphate (C1P), directly binds and activates Group IVA cytosolic phospholipase A₂ (cPLA₂a) to generate eicosanoids. Due to the role of eicosanoids in wound healing, we choose to use our novel genetic mouse model expressing cPLA₂a with an ablated C1P interaction site (KI) to examine the cPLA₂a/C1P interaction in wound healing. Wound closure rate was not affected, but wound maturation was dramatically enhanced by loss of the C1P/cPLA₂α interaction based on the following findings. Wounds in KI mice displayed: i) increased infiltration of dermal fibroblasts into the wound environment; ii …

Modulation Of Electron Transport By Metformin In Cardiac Protection: Role Of Complex I, Ahmed Abdul Hussein Mohsin

Theses and Dissertations

Modulation of mitochondrial complex I during reperfusion reduces cardiac injury. Complex I exists in two structural states: active (A) and deactive (D) with transition from A→D during ischemia. Reperfusion reactivates D→A with an increase in ROS production. Metformin preserves the D-Form. Our aim was to study the contribution of maintenance of deactivation of complex I during early reperfusion by metformin to protect against ischemia reperfusion injury. Our results showed that metformin decreased H9c2 cardiomyoblast apoptosis and total cell death following simulated ischemia for six hours followed by reoxygenation for twenty four hours compared to untreated cells. Reactive oxygen species (ROS) …

Biochemical Analysis Of Putative Single-Stranded Nucleic Acid Binding Proteins In Porphyromonas Gingivalis, Steve H. Kokorelis

Theses and Dissertations

Proteins that bind to both DNA and RNA embody the ability to perform multiple functions by a single gene product. These nucleic acid binding proteins in prokaryotes can play a vital role in many cellular processes, including replication, transcription, gene expression, recombination, and repair, to name a few. Nucleic acid binding proteins have unique functional characteristics that stem from their structural attributes that have evolved in a widely-conserved manner. In Escherichia coli (E. coli), the highly-conserved histone-like protein, HU, which predominates as a heterodimer of HUα and HUβ, has been found to bind to both dsDNA and ssDNA. …

Reversal Of The Npc Phenotype By Start Domain Proteins, Tavis H. Sparrer

Theses and Dissertations

Niemann Pick Type C (NPC) disease is a fatal childhood neurological disease caused by mutations in the NPC-1 protein, resulting in cholesterol buildup in the late endosomes. StarD4 and StarD5 are cholesterol binding proteins that play a role in the intracellular cholesterol transport. In this study we overexpress StarD4 and StarD5 in in vitro and in vivo models, and find evidence of amelioration of the NPC phenotype. This study demonstrates that the overexpression of these proteins has the potential to be a therapeutic treatment for NPC disease.

Survival Model Of Intrahepatic Cholangiocarcinoma; Sex As A Biological Variable, Mary A. Phillippi, Justin L. Mott, Cody J. Wehrkamp, Ying Xie, David Oupicky, Ashley M. Mohr, Bailey A. Stringham

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Glypican-3 Targeting Immunotoxins For The Treatment Of Liver Cancer, Bryan D. Fleming, Daniel Urban, Lu Chen, Matthew Hall, Ira Pastan, Mitchell Ho

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Nitrosative Stress Sensing In Porphyromonas Gingivalis: Structure And Function Of The Heme Binding Transcriptional Regulator Hcpr, Benjamin R. Belvin

Theses and Dissertations

Porphyromonas gingivalis, a Gram negative anaerobe implicated in the progression of periodontal disease, is capable of surviving and causing infection despite high levels of reactive nitrogen species found in the oral cavity due to its efficient nitrosative stress response. HcpR is an important sensor-regulator that plays a vital step in the initiation of the nitrosative stress response in many Gram negative anaerobic bacteria. We employ a combination of X-ray crystallography, SAXS, resonance Raman spectroscopy, UV-Vis spectroscopy, and molecular biology techniques to better understand this key regulator. Knockout of the hcpR gene in W83 P. gingivalis results in the inability of …

Novel Role Of The Nociceptin System As A Regulator Of Glutamate Transporter Expression In Developing Astrocytes, Logan Meyer

Theses and Dissertations

Our previous results showed that oligodendrocyte development is regulated by both nociceptin and its G-protein coupled receptor, the nociceptin/orphanin FQ receptor (NOPR). The present in vitro and in vivo findings show that nociceptin plays a crucial conserved role in both human and rodent brain astrocytes, regulating the levels of the glutamate/aspartate transporter GLAST/EAAT1. This nociceptin-mediated response takes place during a critical developmental window that coincides with astrocyte maturation and synapse formation. GLAST/EAAT1 upregulation by nociceptin is mediated by NOPR and the downstream participation of a complex signaling cascade that involves the interaction of several kinase systems, including PI-3K/AKT, mTOR and …

Study Of Molecular Interactions Of Glycosaminoglycans And Glycosaminoglycan Mimetics With Their Protein Targets, Daniel K. Afosah

Theses and Dissertations

Glycosaminoglycans (GAGs) are complex linear chain carbohydrate molecules found on virtually all animal cell surfaces. Owing to their negatively charged nature, GAGs interact with a number of different proteins. Thus, although they have great potential as therapeutic agents, their apparent promiscuous interactions increase their side effect risk. GAG mimetics, including GAG oligosaccharides and non-saccharide GAG mimetics (NSGMs) are viable approaches to address this. This work discusses sulfated benzofuran thrombin inhibitors with submaximal protease inhibition, sulfated diflavonoid inhibitors of plasmin and GAG oligosaccharides with selectivity for human neutrophil elastase (HNE).

Anticoagulants are very important for the treatment of thrombotic diseases. The …

Optimization Of In Vitro Transcription/Translation Conditions For In Vitro Compartmentalization Studies And Synthesis Of 4-Fluorohistidine, Christine Ring

Theses and Dissertations

Genetic code expansion allows the incorporation of non-canonical amino acids with a variety of new functional groups: fluorescent amino acids,^1-3 azides,^4-6 alkynes,^5-10 and photocrosslinkers.^4,11,12 This incorporation requires the evolution of new tRNA/aminoacyl tRNA sythetase pairs. Traditionally screenings of novel tRNA/aminoacyl tRNA synthetase pairs have been done in vivo. While these in vivo screenings have proven robust, they are limited in multiple ways: non-canonical amino acids (ncAAs) must be nontoxic and bioavailable. Furthermore, library size is limited by transformation efficiency. Lastly, in vivo screenings require substantial amounts of the target ncAA, which is often not available …

Characterization Of A Putative Hemolysin Expressed By Sneathia Amnii, A Preterm Birth-Associated Pathogen, Lizette Carrasco, Kimberly Jefferson

Undergraduate Research Posters

The gram-negative bacteria Sneathia amnii is a poorly-characterized commensal of the female urogenital tract frequently associated with adverse clinical outcomes such as bacterial vaginosis (BV), amnionitis, and preterm labor. To investigate its potential role in virulence, we sought to identify and characterize virulence determinants produced by S. amnii in an effort to better understand the pathogenesis of infectious preterm birth. Through sequencing of the Sn35 genome (type strain of S. amnii), we identified two genes with amino acid sequence similarity and structural similarity to the filamentous hemagglutinin (FHA) protein of Bordetella pertussis and its Type Vb transporter. Because S. amnii …

Separation Of Blood Mixtures Using Fluorescently Labeled Antibodies, Christopher Ehrhardt, Dani Jabado, Emily Brocato

Undergraduate Research Posters

Identifying and analyzing biological mixture samples at a crime scene are of paramount concern for forensic scientists, especially if that type of evidence contains only one cell type. The presence of multiple contributors in a biological evidence sample reduces the probative value of DNA evidence and can sometimes lead to its eventual loss of value. As such, this study was performed in an attempt to examine and evaluate flow cytometry analysis as a means to separate blood mixture samples labeled with fluorescent antibodies. Fluorescein Isothiocyanate (FITC) antibodies were specifically targeted and bound to HLA (Human Leukocyte Antigens) markers present on …