Pharmacology, Toxicology and Environmental Health Commons^™

Investigation Of P-Glycoprotein (Pgp) Induction By Pgp Substrates To Induce Paclitaxel Resistance In Ovarian Cancer Cells, Ryker Penn

Theses & Dissertations

The purpose of this study was to investigate the development of chemotherapeutic resistance to paclitaxel in ovarian cancer cells after treatment with drugs that are substrates for P-glycoprotein (PGP). A core concept of this experiment was to identify if PGP substrate drugs could also act as PGP inducers after prolonged treatment in SKOV-3 ovarian cancer cells. In order to test this, SKOV-3 cells were exposed to either fexofenadine, a PGP substrate used as an antihistamine, or the chemotherapeutic drug vinblastine. After 42 days of drug treatment, ABCB1 gene expression was measured by qRT-PCR. Analysis of ABCB1 expression in treated cells …

Organizational Effects Of Defeminizing Toxicants: Lessons Learned From An Environmental Sentinel Organism, The Fathead Minnow., Jonathan Ali

Theses & Dissertations

Endocrine disrupting compounds (EDCs) are chemicals that interfere with hormone function and are increasingly detected in aquatic environments, where they elicit adverse effects from exposed organisms. The toxicological effects of EDCs can be described as either activational (reversible) or organizational (irreversible), where the latter are associated with adverse outcomes in reproductive performance of adult fish. However, few studies have investigated the organizational impacts of anti-estrogenic or “defeminizing” EDCs, e.g. agrichemicals or pharmacological agents, in an environmentally-relevant or “sentinel” species. The objective of this study was to investigate the impacts of early-life EDC-initiated changes in estrogenic gene expression on organizational effects …

Development Of Neurotensin-Based Radiopharmaceuticals For Neurotensin-Receptor-1-Positive Tumors Targeting, Yinnong Jia

Theses & Dissertations

The neurotensin receptor 1 (NTR1) is overexpressed in many cancers, due to its role as a growth pathway. These NTR1-positive cancers include pancreatic, colon, prostate and breast cancers. In the radiopharmaceutical field, the overexpression of NTR1 in cancer has prompted the development of NTR1-targeted diagnostics and therapeutics. The neurotensin (NT) peptide exhibits low nanomolar affinity for NTR1 and has been the paradigm for NTR1-targeted agents. Since the 1980’s, radiolabeled NT analogs have been developed and evaluated for targeting NTR1-positive cancers. Since native NT is rapidly degraded in vivo by a variety of peptidases, a tremendous amount of effort has been …

Target Validation And Pharmacological Characterization Of Novel Nmdar Modulators, Kiran Sapkota

Theses & Dissertations

The N-methyl-D aspartate receptors (NMDARs) are ligand-gated ion channels, which play important roles in learning and memory. Excessive activity of NMDARs is implicated in damage due to stroke and neurodegenerative diseases, whereas hypoactivity of NMDARs contributes to schizophrenia. The initial goal of my dissertation is to evaluate the potential role of the GluN2D-containing NMDARs in neuropathological, behavioral and cognitive alterations associated with schizophrenia and characterize the pharmacology and mechanisms of action of NMDAR modulators which could potentially be used to modulate these receptors in schizophrenia.

A subanesthetic dose of the NMDAR antagonist ketamine elicits symptoms of schizophrenia. This property led …

Molecular Mechanisms Involved In Neurotoxicity Mediated By Hiv Proteins And Drug Abuse, Yu Cai

Theses & Dissertations

While the advancement of highly active antiretroviral therapy (HAART) has transformed the course of HIV/AIDS from a death sentence to a manageable chronic condition, the prevalence of a constellation of neurological disorders collectively termed as HIV-associated neurocognitive disorders (HAND) continues to persist in these patients. HAND is characterized by cognitive dysfunction, depression, impaired memory and/or deficits in motor skills. The underlying factors leading to HAND have been the subject of extensive research and are thought to be associated with HIV infection in the CNS combined with robust immune activation of resident cells of the CNS. In addition, there is a …

Compensatory Mechanisms And T Cell Migration In Mouse Models Of Dopaminergic Loss, Kristi M. Anderson

Theses & Dissertations

Parkinson’s disease (PD) is the most common neurodegenerative movement disorder and second most common neurodegenerative disorder. PD is characterized by the selective loss of dopaminergic neurons and dopamine neurotransmitter within the substantia nigra and termini in the striatum. Progressive loss of dopaminergic neurons occurs over many years in PD, and by the time movement disorder symptoms manifest, up to 50-70% of dopaminergic neurons have been lost. Several aspects of PD pathology have been described in detail, but a better understanding of PD progression is needed to develop more efficient treatments.

Motor symptoms associated with PD do not manifest until significant …

Development Of Polymer Peptide Conjugates For Enhanced Pancreatic Cancer Imaging, Wen Shi

Theses & Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths in the US with very poor prognosis. All clinically available biomarkers and diagnostic tools either fail to detect early stage PDAC or suffer from low specificity and sensitivity. There is an urgent need for diagnostic agents with greater efficacy for PDAC detection and staging. Nanomaterials such as N-(2-Hydroxypropyl) methacrylamide (HPMA) copolymers can effectively target tumors, and offer novel opportunities for the development of effective diagnostic agents for cancer. However, a major problem of many nanomaterials-based diagnostics is their opsonization and sequestration by the mononuclear phagocyte system (MPS), leading …

Occupational Exposure To Isoflurane Anesthetic Gas In The Research Environment, Andrea R. Mulvenon

Theses & Dissertations

This dissertation is a compilation of studies related to the halogenated anesthetic gas isoflurane. Historically, halogenated anesthetic gases have been used in the health care industry. In 1977 the National Institute for Occupational Safety and Health (NIOSH) issued a recommended exposure limit (REL) of two parts per million (ppm) averaged over one hour of exposure for halogenated anesthetic gases (NIOSH 1977). The purpose of the standard was to protect healthcare workers from exposure to halothane, methoxyflurane, and chloroform. However, isoflurane only became available after the NIOSH REL was adopted. Therefore, the NIOSH REL is not directly applicable to isoflurane. Moreover, …