Medicine and Health Sciences Commons^™

Dual Pi3k/Mtor Inhibition With Bez235 Augments The Therapeutic Efficacy Of Doxorubicin In Cancer Without Influencing Cardiac Function, David E. Durrant

Theses and Dissertations

Cancer continues to be a leading cause death in the United States despite improved treatments. Cancerous lesions form after acquiring oncogenic driver mutations or losing tumor suppressor function in normal cells. Traditional therapies have included use of genotoxic substances that take advantage of the increased growth rate and loss of tumor suppressor function to cause cell death. One such drug is the anthracycline antibiotic doxorubicin (DOX). DOX interchelates into DNA and disrupts transcriptional machinery while also poisoning topoisomerase II. This results in single and double stranded DNA breaks, which if severe enough leads to either necrotic or apoptotic cell death. …

Effects Of Nicotinic Acetylcholine Receptor Agonists In Assays Of Pain-Stimulated And Pain-Depressed Behavior In Rats, Kelen Freitas

Theses and Dissertations

Though a host of analgesics have been developed to alleviate pain, especially acute pain, significant side effects and a lack of long-term efficacy have encouraged research attempts to pursue novel targets that may be associated with fewer side effects or a more sustained efficacy. Among these new targets are members of the nicotinic family of acetylcholine receptors (nAChRs). The non-selective nAChR agonists nicotine and epibatidine have been shown to function as potent antinociceptive drugs in many acute and chronic preclinical pain models, while nicotine has produced analgesic effects in humans. However, these non-selective nAChRs agonists also produce various side effects, …

Biginelli Synthesis And Characterization Of Potentially Anti-Proliferative Dihydropyrimidinone Thione Analogs, Timothy K. Summers

Theses and Dissertations

No abstract provided.

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 …

Elucidation Of A Novel Pathway In Staphylococcus Aureus: The Essential Site-Specific Processing Of Ribosomal Protein L27, Erin A. Wall

Theses and Dissertations

Ribosomal protein L27 is a component of the eubacterial large ribosomal subunit that has been shown to play a critical role in substrate stabilization during protein synthesis. This function is mediated by the L27 N-terminus, which protrudes into the peptidyl transferase center where it interacts with both A-site and P-site tRNAs as well as with 23S rRNA. We observed that L27 in S. aureus and other Firmicutes is encoded with a short N-terminal extension that is not present in most Gram-negative organisms, and is absent from mature ribosomes. The extension contains a conserved cleavage motif; nine N-terminal amino acids are …

Characterization Of Stard4 And Stard6 Proteins In Human Ovarian Tissue And Human Granulosa Cells And Cloning Of Human Stard4 Transcripts, Aisha Shaaban

Theses and Dissertations

Progesterone is essential hormone for pregnancy, which is produced by the human corpus luteum in early pregnancy until the placenta assumes this function. Transport of the cholesterol from the outer to the inner mitochondrial membrane is the rate limiting step for the de novo synthesis of pregnenolone (the precursor to progesterone), a process mediated by STARD1. STARD1 contains a C-terminal lipid binding domain which binds cholesterol and an N-terminal domain targeting STARD1 to the mitochondrial membrane. Unlike STARD1, STARD4 and STARD6 proteins lack a mitochondrial targeting sequence; however, they can bind cholesterol and increase steroidogenesis in model systems. In this …

Chronic Behavioral And Cognitive Deficits In A Rat Survival Model Of Organophosphate Toxicity, Beverly Huang

Theses and Dissertations

Organophosphates (OPs) are a major class of pesticides and nerve agents that elicit acute toxicity by inhibiting acetylcholinesterase (AChE), the enzyme responsible for the degradation of the neurotransmitter acetylcholine in the central and peripheral nervous systems. Acetylcholine accumulation following extensive AChE inhibition leads to an acute cholinergic syndrome characterized by autonomic dysfunction, involuntary movements, muscle fasciculations, respiratory distress, and seizures. Despite their classification as moderate to highly toxic, OP pesticides are the most widely used class of insecticides in the U.S., and are even more commonly used worldwide. Additionally, there is a growing concern that OP nerve agents could be …

Characterization Of A Novel Protease In Staphylococcus Aureus, Adam L. Johnson

Theses and Dissertations

A newly discovered cysteine protease, Prp, has been shown to perform an essential, site-specific cleavage of ribosomal protein L27 in Staphylococcus aureus. In Firmicutes and related bacteria, ribosomal protein L27 is encoded with a conserved N-terminal extension that must be removed to expose residues critical for ribosome function. Uncleavable and pre-cleaved variants were unable to complement an L27 deletion in S. aureus, indicating that this N-terminal processing event is essential and likely plays an important regulatory role. The gene encoding the responsible protease (prp) has been shown to be essential, and is found in all organisms …

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 …