Digital Commons Network^™

Integrated Nanoscale Imaging And Spatial Recognition Of Biomolecules On Surfaces, Congzhou Wang

Theses and Dissertations

Biomolecules on cell surfaces play critical roles in diverse biological and physiological processes. However, conventional bulk scale techniques are unable to clarify the density and distribution of specific biomolecules in situ on single, living cell surfaces at the micro or nanoscale. In this work, a single cell analysis technique based on Atomic Force Microscopy (AFM) is developed to spatially identify biomolecules and characterize nanomechanical properties on single cell surfaces. The unique advantage of these AFM-based techniques lies in the ability to operate in situ (in a non-destructive fashion) and in real time, under physiological conditions or controlled micro-environments.

First, AFM-based …

Development Of Non-Traditional Platinum Anticancer Agents: Trans-Platinum Planar Amine Compounds And Polynuclear Platinum Compounds, Daniel E. Lee

Theses and Dissertations

Development of Non-Traditional Platinum Anticancer Agents: trans-Platinum Planar Amine Compounds and Polynuclear Platinum Compounds

By Daniel E. Lee, Ph.D.

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

Virginia Commonwealth University, 2015

Major Director: Nicholas P Farrell, Ph.D., Professor, Department of Chemistry

Platinum anticancer compounds with cis geometry, similar to cisplatin, have been explored to circumvent the cisplatin resistance; however, they were not considered broadly active in cisplatin cells due to exhibiting similar or same cell death mechanism as cisplatin. Platinum compounds with trans geometry were less studied …

Development Of Clinically Relevant In Vitro Performance Tests For Powder Inhalers, Xiangyin Wei

Theses and Dissertations

While realistic in vitro testing of dry powder inhalers (DPIs) can be used to establish in vitro–in vivo correlations (IVIVCs) and predict in vivo lung doses, the aerodynamic particle size distributions (APSDs) of those doses and their regional lung deposition remains unclear. Four studies were designed to improve testing centered on the behavior of Novolizer®. Different oropharyngeal geometries were assessed by testing different mouth-throat (MT) models across a realistic range of inhalation profiles (IPs) with Salbulin® Novolizer®. Small and large Virginia Commonwealth University (VCU) and Oropharyngeal Consortium (OPC) models produced similar ranges for total lung dose in vitro (TLD …

Structural Determinants Of Abuse-Related Neurochemical And Behavioral Effects Of Para-Substituted Methcathinone Analogs In Rats, Julie S. Bonano

Theses and Dissertations

Methcathinone (MCAT) is the β-ketone analog of methamphetamine, and like its amphetamine analog, MCAT functions as a monoamine releaser that selectively promotes the release of dopamine (DA) and norepinephrine (NE) over serotonin (5-HT). MCAT produces amphetamine-like psychostimulant effects and is classified as a Schedule I drug of abuse by the United States Drug Enforcement Administration (DEA). Recently, synthetic MCAT analogs have emerged as designer drugs of abuse in Europe and the United States and have been marketed under deceptively benign names like “bath salts” in an attempt to evade legal restriction. These dangerous, recently emergent and novel drugs of abuse …

Relationship Between Autophagy, Senescence, And Dna Damage In Radiation Sensitization By Parp Inhibition, Moureq Alotaibi

Theses and Dissertations

Radiotherapy continues to be a primary modality in the treatment of cancer. DNA damage induced by radiation can promote apoptosis as well as both autophagy and senescence, where autophagy and senescence can theoretically function to prolong tumor survival. A primary aim of this work was to investigate the hypothesis that autophagy and/or senescence could be permissive for DNA repair, thereby facilitating tumor cell recovery from radiation-induced growth arrest and/or cell death. In addition, studies were designed to elucidate the involvement of autophagy and senescence in radiation sensitization by PARP inhibitors and the re-emergence of a proliferating tumor cell population. In …

Effects Of Hiv-1 Tat On The Enteric Nervous, Joy Ngwainmbi

Theses and Dissertations

More than 1.2 million people are estimated to be currently living with the human immunodeficiency virus (HIV) in the United States of America. The gastrointestinal (GI) tract is both a major target and an important component of HIV pathogenesis. The GI processes that are dysregulated during HIV infection are controlled by the enteric nervous system (ENS). Indeed, both clinical and experimental studies have implicated the ENS in HIV and simian immunodeficiency virus (SIV) pathogenesis. In addition to direct viral effects, the HIV virus also indirectly affects the GI tract via cellular and/or viral toxins released by infected cells. Trans-activator of …

Elaboration And Design Of Α7 Nachr Negative Allosteric Modulators, Osama I. Alwassil

Theses and Dissertations

α7 Neuronal nicotinic acetylcholine receptors are one of two major classes of receptors responsible for cholinergic neurotransmission in the central nervous system. The existence of α7 neuronal nAChRs in different regions of the nervous system suggests their involvement in certain essential physiological functions as well as in disorders such as Alzheimer’s disease (AD), drug dependence, and depression. This project was aimed toward the discovery and development of small–molecule arylguanidines that modulate α7 nAChR function with improved subtype-selectivity through an allosteric approach. Identifying the required structural features of these small molecules allowed optimization of their negative allosteric modulator (NAM) actions at …

Development Of Irreversible Substrate Competitive Probes For Pka Activity, Robert A. Coover

Theses and Dissertations

The current environment for drug discovery and disease treatment relies heavily on genomic analysis, structural biology and chemical biology techniques. With the enormous advances in genomic analysis and structural biology, the use of and desire for targeted therapies has increased. However, as more genomic data for cancer disease state pathology becomes available we must ask increasingly difficult questions and even produce new technologies, such as activity-based probes, to answer these questions.

In particular, targeted kinase inhibitors for the treatment of cancer has become a mainstay for drug development for both industry and academia, but it is evident that the genomic …

Xlf-Dependent Nonhomologous End Joining Of Complex Dna Double-Strand Breaks With Proximal Thymine Glycol And Screening For Xrcc4-Xlf Interaction Inhibitors, Mohammed Al Mohaini

Theses and Dissertations

DNA double-strand breaks induced by ionizing radiation are often accompanied by ancillary oxidative base damage that may prevent or delay their repair. In order to better define the features that make some DSBs repair-resistant, XLF-dependent nonhomologous end joining of blunt-ended DSB substrates having the oxidatively modified nonplanar base thymine glycol (Tg) at the first (Tg1) , second (Tg2), third (Tg3) or fifth (Tg5) positions from one 3’ terminus was examined in human whole-cell extracts. Tg at the third position had little effect on end-joining even when present on both ends of the break. However, Tg as the terminal or penultimate …

Expression And Pharmacological Modulation Of Pain-Depressed Behavior In Rats, Michael D. Leitl

Theses and Dissertations

Pain is often associated with depression of behavior and mood, and relief of pain-related depression is a common goal of treatment. This goal of this dissertation was to conduct preclinical research experiments designed to address a set of three inter-related aims that examine the expression, mechanisms and treatment of pain-related depression of Intracranial Self-Stimulation (ICSS) in rats. First, studies evaluated the hypothesis that acute acid-induced depression of ICSS was mediated by a kappa opioid receptor mediated decrease in mesolimbic dopamine release in the nucleus accumbens. Results support a role for depressed mesolimbic dopamine release in pain-related depression of ICSS; however, …

Pemetrexed, A Modulator Of Amp-Activated Kinase Signaling And An Inhibitor Of Wild Type And Mutant P53, Stuti Agarwal

Theses and Dissertations

New drug discoveries and new approaches towards diagnosis and treatment have improved cancer therapeutics remarkably. One of the most influential and effective discoveries in the field of cancer therapeutics was antimetabolites, such as the antifolates. The interest in antifolates increased as some of the antifolates showed responses in cancers, such as mesothelioma, leukemia, and breast cancers. When pemetrexed (PTX) was discovered, our laboratory had established that the primary mechanism of action of pemetrexed is to inhibit thymidylate 22 synthase (TS) (E. Taylor et al., 1992). Preclinical studies have shown that PTX has a broad range of antitumor activity in human …

Synthetic Cannabinoids Versus Delta-9-Tetrahydrocannabinol: Abuse-Related Consequences Of Enhanced Efficacy At The Cannabinoid 1 Receptor, Travis Grim

Theses and Dissertations

In the past ten years, synthetic cannabinoids (SC) have emerged as drugs of abuse. Unlike D⁹-tetrahydrocannabinol (THC), many SCs are associated with serious health complications and death. One way in which THC and SCs differ lies with their enhanced potency and efficacy at the CB₁ receptor. No current methods exist to measure efficacy at the CB₁ receptor in vivo, and the abuse-related properties of SC cannabinoids are not well explored. Here, we utilized CB₁ wild type (WT), heterozygous (HET), and knockout (KO) mice. By employing CB₁ ligands which differ in efficacy we have …