Pharmacy and Pharmaceutical Sciences Commons^™

Clinical Outcomes Associated With Time To Antimicrobial Therapy Change From Vancomycin To Daptomycin In Staphylococcal Bacteremia, Sarah J. Tennant

Theses and Dissertations--Pharmacy

Background: Staphylococcus aureus is an aerobic, Gram positive commensal organism that is capable of causing a wide spectrum of disease. This study contributes to previously published literature regarding daptomycin versus vancomycin use in S. aureus bacteremia (SAB).

Methods: Adult patients admitted between 2010 and 2014, billed for ICD-9 code V09.0, 038.11, 038.12, 041.11, or 041.12, and received vancomycin and daptomycin were included in this retrospective analysis. Patients were stratified by time to change in antibiotics from vancomycin to daptomycin to the early switch (1-3 days), intermediate switch (4-7 days), or late switch (8 days or later) group. The primary outcome …

Rna Nanotechnology For Next Generation Targeted Drug Delivery, Fengmei Pi

Theses and Dissertations--Pharmacy

The emerging field of RNA nanotechnology is developing into a promising platform for therapeutically application. Utilizing the state-of-art RNA nanotechnology, RNA nanoparticles can be designed and constructed with controllable shape, size for both RNA therapeutics and chemical drug delivery. The high homogeneity in particle size and ease for RNA therapeutic module conjugation, made it feasible to explore versatile RNA nanoparticle designs for preclinical studies.

One vital module for therapeutic RNA nanoparticle design is RNA aptamer, which can enable the RNA nanoparticles find its specific target for targeted drug delivery. A system of screening divalent RNA aptamers for cancer cell targeting …

Investigating Mechanisms Determining Cancer Cell Sensitivity To Carfilzomib And Novel Strategies To Overcome Resistance, Lin Ao

Theses and Dissertations--Pharmacy

Proteasome inhibitors (PIs) are a class of FDA-approved anti-cancer agents which includes the first-generation PI bortezomib (BTZ) and second-generation carfilzomib (CFZ). Drug resistance is a major challenge in PI therapy with no solution currently available. While a few resistance mechanisms had been proposed for BTZ, little was known about CFZ resistance before the start of our studies. In this dissertation work, we investigated multiple mechanisms contributing to CFZ resistance—alterations in the drug transporter activity, metabolic stability, and proteasome activity profiles—and evaluated potential strategies to overcome CFZ resistance.

We observed marked upregulation of the drug efflux transporter P-glycoprotein (P-gp) in our …

Rna As A Unique Polymer To Build Controllable Nanostructures For Nanomedicine And Nanotechnology, Hui Li

Theses and Dissertations--Pharmacy

RNA nanotechnology is an emerging field that involves the design, construction and functionalization of nanostructures composed mainly of RNA for applications in biomedical and material sciences. RNA is a unique polymer with structural simplicity like DNA and functional diversity like proteins. A variety of RNA nanostructures have been reported with different geometrical structures and functionalities. This dissertation describes the design and construction of novel two-dimensional and three-dimensional self-assembled RNA nanostructures with applications in therapeutics delivery, cancer targeting and immunomodulation. Firstly, by using the ultra-stable pRNA three-way junction motif with controllable angles and arm lengths, tetrahedral architectures composed purely of RNA …

Roles Of Abcg5 Abcg8 Cholesterol Transporter In Lipid Homeostasis, Yuhuan Wang

Theses and Dissertations--Pharmacy

The ABCG5 ABCG8 (G5G8) sterol transporter promotes cholesterol secretion into bile and opposes dietary sterol absorption in the small intestine. An emerging body of literature suggests that G5G8 links sterol flux to various risk factors for metabolic syndrome (MetS) and nonalcoholic fatty liver disease (NAFLD). Therapeutic approaches that accelerate G5G8 activity may augment reverse cholesterol transport (RCT) and provide beneficial effects in the prevention and treatment of cardiovascular and liver disease.

Mice lacking leptin (ob/ob) or its receptor (db/db) are obese, insulin resistant in part due to the reduced levels of hepatic G5G8 and biliary cholesterol. …

Medication Misadventures: The Case Of Benzodiazepines, Sarah E. Wixson

Theses and Dissertations--Pharmacy

For patients afflicted with symptoms of anxiety and insomnia, benzodiazepines are generally a safe and effective short-term pharmacological treatment option. Although considered safer than other sedative-hypnotic medications, substantial concern exists regarding the addictive nature and abuse potential of benzodiazepines along with potentially inappropriate prescribing and utilization in clinically vulnerable populations. These medication misadventures can have a significant impact on public health. Examples of medication misadventures as they pertain to benzodiazepines include the prescribing and use in clinically vulnerable populations for whom they are contraindicated or their efficacy has not been evaluated, the development of tolerance or addiction, abuse of the …

Kinetics And Mechanisms Of Crystal Growth Inhibition Of Indomethacin By Model Precipitation Inhibitors, Dhaval D. Patel

Theses and Dissertations--Pharmacy

Supersaturating Drug Delivery Systems (SDDS) could enhance oral bioavailability of poorly water soluble drugs (PWSD). Precipitation inhibitors (PIs) in SDDS could maintain supersaturation by inhibiting nucleation, crystal growth, or both. The mechanisms by which these effects are realized are generally unknown. The goal of this dissertation was to explore the mechanisms underpinning the effects of model PIs including hydroxypropyl β-cyclodextrins (HP-β-CD), hydroxypropyl methylcellulose (HPMC), and polyvinylpyrrolidone (PVP) on the crystal growth of indomethacin, a model PWSD. At high degrees of supersaturation (S), the crystal growth kinetics of indomethacin was bulk diffusion-controlled, which was attributed to a high energy form deposited …

Design, Synthesis, And Pharmacological Evaluation Of Three Series Of Lobelane Analogs As Inhibitors Of The Vesicular Monoamine Transporter (Vmat2), John P. Culver

Theses and Dissertations--Pharmacy

Methamphetamine (METH) abuse is a serious problem in the United States and worldwide. The reward experienced by METH users is due to the increase in extracellular dopamine (DA) concentrations caused by an interaction between METH and the DA transporter (DAT) as well as the Vesicular Monoamine Transporter-2 (VMAT2). The reward felt by users of METH leads to further use of the drug and subsequent abuse. The current project examined the ability of three novel series of lobelane analogs to interact with a binding site on the Vesicular Monoamine Transporter-2 (VMAT2) in an attempt to inhibit the effects of METH. Lobelane …

Chemoenzymatic Studies To Enhance The Chemical Space Of Natural Products, Jhong-Min Chen

Theses and Dissertations--Pharmacy

Natural products provide some of the most potent anticancer agents and offer a template for new drug design or improvement with the advantage of an enormous chemical space. The overall goal of this thesis research is to enhance the chemical space of two natural products in order to generate novel drugs with better in vivo bioactivities than the original natural products.

Polycarcin V (PV) is a gilvocarcin-type antitumor agent with similar structure and comparable bioactivity with the principle compound of this group, gilvocarcin V (GV). Modest modifications of the polyketide-derived tetracyclic core of GV had been accomplished, but the most …

A Molecular-Level View Of The Physical Stability Of Amorphous Solid Dispersions, Xiaoda Yuan

Theses and Dissertations--Pharmacy

Many pharmaceutical compounds being developed in recent years are poorly soluble in water. This has led to insufficient oral bioavailability of many compounds in vitro. The amorphous formulation is one of the promising techniques to increase the oral bioavailability of these poorly water-soluble compounds. However, an amorphous drug substance is inherently unstable because it is a high energy form. In order to increase the physical stability, the amorphous drug is often formulated with a suitable polymer to form an amorphous solid dispersion. Previous research has suggested that the formation of an intimately mixed drug-polymer mixture contributes to the stabilization …

Molecular And Functional Investigation Of Cancer-Type And Liver-Type Variants Of Organic Anion Transporting Polypeptide 1b3, Nilay Thakkar

Theses and Dissertations--Pharmacy

OATP1B3 belongs to the OATP (organic anion transporting polypeptides) superfamily, responsible for mediating the transport of various endogenous and xenobiotic substrates. OATP1B3 was initially reported to be expressed exclusively in the hepatocytes where it mediates the uptake of numerous endogenous substrates (e.g. bile acids, steroid hormone conjugates) and several clinically relevant drugs including anticancer drugs. Later, a number of studies reported that OATP1B3 is also frequently expressed in multiple types of cancers and may be associated with differing clinical outcomes. However, a detailed investigation on the expression, localization and functions of OATP1B3 expressed in cancer has been lacking. In this …

Antibiotics Targeting Tuberculosis: Biosynthesis Of A-102395 And Discovery Of Novel Actinomycins, Wenlong Cai

Theses and Dissertations--Pharmacy

The increase in antibiotic resistance of many bacterial strains including multidrug-resistant tuberculosis (MDR-TB) due to over- and misuse of antibiotics is a serious medical and economical problem. Therefore discovery and development of new antibiotics are urgently needed. Two projects were undertaken to address the need for new anti-tuberculosis antibiotics.

1. Discovery of new chemical entities. A-102395, a new nucleoside inhibitor of bacterial MraY (translocase I, EC 2.7.8.13) that is essential for bacterial survival, was isolated from the culture broth of Amycolatopsis sp. SANK 60206 in 2007. Although A-102395 is a potent inhibitor of translocase I with IC50 of 11 nM, …

Elucidating The Mechanism Of Lipl: A Non-Heme Fe(Ii), Α -Ketoglutarate: Uridine-5’-Monophosphate Dioxygenase, Anwesha Goswami

Theses and Dissertations--Pharmacy

Several nucleoside natural product antibiotics from Streptomyces sp. and actinomycetes have recently been shown to target bacterial peptidoglycan cell wall biosynthesis by inhibiting the bacterial translocase I (MraY). The biosynthetic gene clusters for A-90289, liposidomycins and caprazamycins revealed a protein with sequence similarity to proteins annotated as α-KG:taurine dioxygenases (TauD). This enzyme (LipL) is a mononuclear, non-heme, Fe(II) dependent α-keto glutarate (α-KG) :uridine monophosphate (UMP) dioxygenase responsible for the net dephosphorylation and two electron oxidation of UMP to uridine-5’-aldehyde. The postulated reaction coordinates involving the activation of the C-5’ center in UMP and the corresponding formation of uridine-5’-aldehyde are modeled …

Beyond Peroxisome: Abcd2 Modifies Pparα Signaling And Identifies A Subclass Of Peroxisomes In Mouse Adipose Tissue, Xiaoxi Liu

Theses and Dissertations--Pharmacy

ABCD2 (D2) has been proposed as a peroxisomal long-chain acyl-CoA transporter that is essential for very long chain fatty acid metabolism. In the livers of mice, D2 is highly induced by fenofibrate, a PPARα ligand that has been widely used as a lipid lowering agent in the treatment of hypertriglyceridemia. To determine if D2 is a modifier of fibrate responses, wild-type and D2 deficient mice were treated with fenofibrate for 14 days. The absence of D2 altered expression of gene clusters associated with lipid metabolism, including PPARα signaling. Using 3T3-L1 adipocytes, which express high levels of D2, we confirmed that …

Quantification Of Factors Governing Drug Release Kinetics From Nanoparticles: A Combined Experimental And Mechanistic Modeling Approach, Kyle Daniel Fugit

Theses and Dissertations--Pharmacy

Advancements in nanoparticle drug delivery of anticancer agents require mathematical models capable of predicting in vivo formulation performance from in vitro characterization studies. Such models must identify and incorporate the physicochemical properties of the therapeutic agent and nanoparticle driving in vivo drug release. This work identifies these factors for two nanoparticle formulations of anticancer agents using an approach which develops mechanistic mathematical models in conjunction with experimental studies.

A non-sink ultrafiltration method was developed to monitor liposomal release kinetics of the anticancer agent topotecan. Mathematical modeling allowed simultaneous determination of drug permeability and interfacial binding to the bilayer from release …

Synthesis And Biological Evaluation Of Novel Resveratrol And Combretastatin A4 Derivatives As Potent Anti-Cancer Agents, Nikhil Reddy Madadi

Theses and Dissertations--Pharmacy

Resveratrol has been reported as a potential anticancer agent but cannot be used as an antitumor drug due to its chemical and metabolic instability. We have designed and synthesized 184 novel compounds related to resveratrol in an attempt to produce more potent and drug-like molecules. We have identified a tetrazole analog of resveratrol, ST-145(a) as a lead anticancer agent from the resveratrol analog series of compounds with a GI₅₀ value of less than 10nM against almost all the human cancer cell lines in the National Cancer Institute’s screening panel.

In a separate study, we tested the hypothesis that the …

Multi-Component Microparticulate/Nanoparticulate Dry Powder Inhalation Aerosols For Targeted Pulmonary Delivery, Xiaojian Li

Theses and Dissertations--Pharmacy

The aim of the work was to design, manufacture, and characterize targeted multi-component dry powder aerosols of (non-destructive) mucolytic agent (mannitol), antimicrobial drug (tobramycin or azithromycin), and lung surfactant mimic phospholipids (DPPC:DPPG=4:1 in molar ratio). The targeted dry powder for inhalation formulation for deep lung delivery with a built-in rationale of specifically interfering several disease factors of chronic infection diseases in deep lungs such as cystic fibrosis, pneumonia, chronic bronchitis, and etc. The dry powder aerosols consisting of selected chemical agents in one single formulation was generated by using spray drying from organic solution.

The physicochemical properties of multi-component dry …

Human Butyrylcholinesterase Mutants For Cocaine Detoxification, Shurong Hou

Theses and Dissertations--Pharmacy

Cocaine is one of the most reinforcing drugs of abuse and has caused serious medical and social problems. There is no FDA-approved medication specific for cocaine. It is of a high priority to develop an effective therapeutic treatment for cocaine abuse. Human butyrylcholinesterase (BChE) has been recognized as a promising candidate of enzyme therapy to metabolize cocaine into biologically inactive metabolites and prevent it from reaching central nervous system (CNS). However, the catalytic activity of wide-type human BChE against cocaine is not sufficiently high for treatment of cocaine abuse. Dr. Zhan’s lab has successfully designed and discovered a series of …

Lobelane Analogs With Various Methylene Linker Lengths And Acyclic Lobelane Analogs As Potential Pharmacotherapies To Treat Methamphetamine Abuse, Zheng Cao

Theses and Dissertations--Pharmacy

Methamphetamine interacts with vesicular monoamine transporter-2 (VMAT2) to inhibit dopamine (DA) uptake and promotes DA release from presynaptic vesicles, increasing cytosolic DA available for methamphetamine-induced reverse transport by DA transporters. By inhibiting VMAT2, lobelane, a defunctionalized, saturated lobeline analog, decreases methamphetamine-evoked DA release and methamphetamine self-administration in rats. In this dissertation structure-activity relationships around the lobelane structure were investigated on racemic lobelane analogs with varying methylene linker lengths at central piperidine ring. Affinity for dihydrotetrabenazine (DTBZ) sites on VMAT2 and for inhibition of VMAT2 function was determined to be 0.88-63 and 0.024-4.6 µM, respectively, and positively correlated. The most potent …

Investigating Structure And Protein-Protein Interactions Of Key Post-Type Ii Pks Tailoring Enzymes, Theresa E. Downey

Theses and Dissertations--Pharmacy

Type II polyketide synthase (PKS) produced natural products have proven to be an excellent source of pharmacologically relevant molecules due to their rich biological activities and chemical scaffolds. Type II-PKS manufactured polyketides share similar polycyclic aromatic backbones leaving their diversity to stem from various chemical additions and alterations facilitated by post-PKS tailoring enzymes. Evidence suggests that post-PKS tailoring enzymes form complexes in order to facilitate the highly orchestrated process of biosynthesis. Thus, protein-protein interactions between these enzymes must play crucial roles in their structures and functions. Despite the importance of these interactions little has been done to study them. In …

Flavonoids With Novel Nicotinic Activity As Potential Pharmacotherapies To Treat Ethanol-Induced Neurotoxicity, Joseph A. Lutz

Theses and Dissertations--Pharmacy

Ethanol causes neurotoxicity via several mechanisms at different points in the cycle of dependence, including neuroinflammation and oxidative stress during ethanol exposure as well as excitotoxicity during ethanol withdrawal. The primary therapeutic implication is that ethanol-induced neurotoxicity requires multifunctional pharmacotherapies which reduce all mechanisms. Using an innovative pharmacological high throughput screening method on a large plant extract library we discovered flavonoids with alpha7 nicotinic acetylcholine receptor (nAChR) activity. In addition to their well-known anti-inflammatory and antioxidant properties, this novel activity means they can potentially reduce excitotoxicity and therefore makes them ideal for inhibition of ethanol-induced neurotoxicity. Rhamnetin, the candidate compound, …

Phosphatidylinositol 3-Kinase (Pi3k) As A Therapeutic Target In Nsclc, Christopher W. Stamatkin

Theses and Dissertations--Pharmacy

Deregulated activation of phosphatidylinositol 3-kinase (PI3K) pathway is central to many human malignancies. The functions of this pathway are critical for normal cell metabolism, proliferation, and survival. In lung cancers, the PI3K pathway activity is often aberrantly driven by multiple mutations, including EGFR, KRAS, and PIK3CA. Molecules targeting the PI3K pathway are intensely investigated as potential anti-cancer agents. Although inhibitors of the pathway are currently in clinical trials, rational and targeted use of these compounds, alone or in combination, requires an understanding of isoform-specific activity in context. We sought to identify class IA PI3K enzyme (p110a/PIK3CA, p110b/PIK3CB, p110d/PIK3CD) activities using …

Preclinical Development Of Phytocannabinoid- And Endocannabinoid- Based Pharmacotherapies For The Treatment Of Ethanol-Induced Neurodegeneration, Daniel J. Liput

Theses and Dissertations--Pharmacy

Excessive ethanol consumption, characteristic of alcohol use disorders (AUDs), is associated with widespread neurodegeneration and cognitive and behavioral impairments that may contribute to the chronic and relapsing nature of alcoholism. Therefore, identifying novel targets that can afford neuroprotection will undoubtedly aid current treatment strategies for AUDs. The cannabinoids have been shown to provide neuroprotection in a variety of preclinical models of neurodegeneration; however minimal data is available regarding the use of cannabinoid-based pharmacotherapies for treating ethanol-induced neurodegeneration. Therefore, the current dissertation examined the overarching hypothesis: the cannabinoids are a therapeutic strategy to afford neuroprotection in the context of ethanol-induced neurodegeneration. …

Investigating Key Post-Pks Enzymes From Gilvocarcin Biosynthetic Pathway, Nidhi Tibrewal

Theses and Dissertations--Pharmacy

Gilvocarcin V (GV) belongs to the angucycline class of antibiotics that possesses remarkable anticancer and antibacterial activities with low toxicity. Gilvocarcin exhibits its light induced anticancer activity by mediating crosslinking between DNA and histone H3. When photo-activated by near-UV light, the C8 vinyl group forms a [2+2] cycloadduct with thymine residues of double stranded DNA. _D-fucofuranose is considered essential for histone H3 interactions. However, the poor water solubility has rendered it difficult to develop gilvocarcin as a drug. We aim to design novel gilvocarcin analogues with improved pharmaceutical properties through chemo-enzymatic synthesis and mutasynthesis. Previous studies have characterized many …

High-Activity Mutants Of Human Butyrylcholinesterase For Cocaine Abuse Treatment, Liu Xue

Theses and Dissertations--Pharmacy

Cocaine is a widely abused drug without an FDA-approved medication. It has been recognized as an ideal anti-cocaine medication to accelerate cocaine metabolism producing biologically inactive metabolites via a route similar to the primary cocaine-metabolizing pathway, i.e. butyrylcholinesterase (BChE)-catalyzed hydrolysis. However, the native BChE has a low catalytic activity against cocaine. We recently designed and discovered a set of BChE mutants with a high catalytic activity specifically for cocaine. An ideal, therapeutically valuable mutant of human BChE should have not only a significantly improved catalytic activity against cocaine, but also certain selectivity for cocaine over neurotransmitter acetylcholine (ACh) such …

Computational Modeling, Design, And Characterization Of Cocaine-Metabolizing Enzymes For Anti-Cocaine Medication, Lei Fang

Theses and Dissertations--Pharmacy

Cocaine is a widely abused and addictive drug, resulting in serious medical and social problems in modern society. Currently, there is no FDA-approved medication specific for cocaine abuse treatment. The disastrous medical and social consequences of cocaine abuse have made the development of an anti-cocaine medication a high priority. However, despite decades of efforts, traditional pharmacodynamic approach has failed to yield a truly useful small-molecule drug due to the difficulties inherent in blocking a blocker like cocaine without affecting the normal functions of the transporters or receptors. An alternative approach, i.e. pharmacokinetic approach, is to interfere with the delivery of …

High Dose Simvastatin As A Potential Anticancer Therapy In Leukemia Patients, Tamer Ahmed

Theses and Dissertations--Pharmacy

Simvastatin is a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor that is used for the treatment of hyperlipidemia. Simvastatin has recently been studied for its potential use in cancer therapy. In-vitro studies have shown that simvastatin displays anticancer activity, but at concentrations unlikely to be achieved in patients being receiving typical antihyperlipidemic treatment doses. Thus, several clinical trials were conducted to study the tolerability of high dose statins in cancer patients. The maximum tolerated dose of simvastatin was determined to be 15 mg/kg/day, 25-fold higher than a typical dose. However, it is not known if simvastatin plasma concentrations can reach those …

Towards Elucidation Of A Viral Dna Packaging Motor, Chad T. Schwartz

Theses and Dissertations--Pharmacy

Previously, gp16, the ATPase protein of phi29 DNA packaging motor, was an enigma due to its tendency to form multiple oligomeric states. Recently we employed new methodologies to decipher both its stoichiometry and also the mechanism in which the protein functions to hydrolyze ATP and provide the driving force for DNA packaging. The oligomeric states were determined by biochemical and biophysical approaches. Contrary to many reported intriguing models of viral DNA packaging, it was found that phi29 DNA packaging motor permits the translocation of DNA unidirectionally and driven cooperatively by three rings of defined shape. The mechanism for the generation …

Preclinical And Clinical Development Of The Lipophilic Camptothecin Analogue Ar-67, Eleftheria Tsakalozou

Theses and Dissertations--Pharmacy

AR-67 is a lipophilic third generation camptothecin analogue, currently under early stage clinical trials. It acts by targeting Topoisomerase 1 (Top1), a nuclear enzyme essential for DNA replication and transcription and is present in two forms, the pharmacologically active lipophilic lactone and the charged carboxylate. In oncology patients participating in a phase I clinical trial, AR-67 lactone was the predominant species in plasma. Similarly to other camptothecins, the identified dose-limiting toxicities for AR-67 were neutropenia, thrombocytopenia and fatigue. In addition, in vitro metabolism studies indicated AR-67 lactone as a substrate for CYP3A4/5 as well as the UGT1A7 and UGT1A8 enzymes …

The Pharmacokinetics Of Metal-Based Engineered Nanomaterials, Focusing On The Blood-Brain Barrier, Mo Dan

Theses and Dissertations--Pharmacy

Metal-based engineered nanomaterials (ENMs) have potential to revolutionize diagnosis, drug delivery and manufactured products, leading to greater human ENM exposure. It is crucial to understand ENM pharmacokinetics and their association with biological barriers such as the blood-brain barrier (BBB). Physicochemical parameters such as size and surface modification of ENMs play an important role in ENM fate, including their brain association. Multifunctional ENMs showed advantages across the highly regulated BBB. There are limited reports on ENM distribution among the blood in the brain vasculature, the BBB, and brain parenchyma.

In this study, ceria ENM was used to study the effect of …