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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Quantification of Synthetic Cathinones in Rat Brain Using HILIC–ESI-MS/MS

Peters, Jacob R., Keasling, Robert, Brown, Stacy D., Pond, Brooks B. 16 November 2016 (has links)
The abuse of synthetic cathinones, formerly marketed as “bath salts”, has emerged over the last decade. Three common drugs in this class include 3,4-methylenedioxypyrovalerone (MDPV), 4-methylmethcathinone (mephedrone), and 3,4-methylenedioxymethcathinone (methylone). An LC–MS/MS method has been developed and validated for the simultaneous quantification of MDPV, mephedrone, and methylone in brain tissue. Briefly, MDPV, mephedrone, methylone, and their deuterium-labeled analogs were subjected to solid phase extraction (SPE) and separated using an HILIC Silica Column. The HPLC was coupled to a Shimadzu IT-TOF (ion trap-time of flight) system with the electrospray source running in positive mode (+ESI). The method was validated for precision, accuracy, and extraction efficiency. All inter-day and intra-day % RSD (percent relative standard deviation) and % error values were less than 15% and extraction efficiency exceeded 80%. These conditions allowed for limits of detection of 1ng/mL for MDPV, and 5 ng/mL for both mephedrone and methylone. The limits of quantification were determined to be 5ng/mL for MDPV and 10 ng/mL for mephedrone and methylone. The method was utilized to evaluate the pharmacokinetics of these drugs in adult male rats following administration of a drug cocktail including MDPV, mephedrone, and methylone. All three compounds reached peak concentrations in the brain within 15 min. Although methylone and mephedrone were administered at the same dose, the peak concentration (Cmax) of mephedrone in the brain was significantly higher than that for methylone, as was the area under the curve (AUC). In summary, this quick and sensitive method for measuring synthetic cathinones may be used for future pharmacokinetic investigations of these drugs in target tissue.
32

Contemporary Approaches For Teaching Medicinal Chemistry

Brown, Stacy D., Coop, Andy, Trippier, Paul, Walters, Eric 16 July 2017 (has links)
As the profession of pharmacy has transitioned from a chemistry-centered profession to a patient-centered profession, the role of medicinal chemistry in the curriculum has evolved. There is decreased emphasis on memorization of chemical structures, and priority placed on relating these structures to ADME, physical properties, and pharmacodynamics. Simultaneously, the delivery of this content has shifted from traditional lecture format to other styles. Here we discuss some new approaches to teaching medicinal chemistry.
33

Stability of Commercially-Available Grape and Compounded Cherry Oral Vancomycin Preparations Stored in Syringes and Cups

Brown, Stacy D., Lewis, Paul O., Kirk, Loren M., Luu, Yao 11 July 2015 (has links)
Abstract available in the American Journal of Pharmaceutical Education.
34

Determination of JP-8 Components in Soils Using Solid-Phase Microextraction–Gas Chromatography–Mass Spectrometry

Brown, Stacy D., Rickrode, Mark, Caldwell, Thomas 01 August 2008 (has links)
Jet Propellant-8 (JP-8) is a military fuel associated with a large percentage of chemical exposures documented by the US Department of Defense. A fast and sensitive solid-phase microextraction–gas chromatographic–mass spectrometric method has been developed for the determination of 34 ‘marker compounds’ found in JP-8. Linear ranges were determined for each marker component and precision was measured for these components over four concentrations within each calibration range. The method was applied for the analysis of JP-8 components from soil. The use of SPME over other sample extraction techniques eliminates solvents, minimizes sample handling, and increases sensitivity.
35

Regorafenib Enhances Lethality of Sildenafil and Curcumin in Colorectal Cancer Cells

Owusu, Kervin Benjamin 01 January 2019 (has links)
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 drug concentrations (~2.0 μM), our laboratory has shown that both sildenafil and curcumin interact to synergistically down regulate the expression of multiple cyto-protective molecular chaperones and kill CRC cells in a greater than additive manner in vitro and suppress the growth of colon cancer tumors in vivo. In this study, the expression of PDGFRb and PDGF in the plasma was increased in colon tumor bearing mice previously exposed to curcumin and sildenafil. Further, the in vitro killing potential of curcumin and sildenafil was shown to be reduced in evolved tumor cells from these mice. The purpose of this study was to determine whether down regulation of PDGFRb using regorafenib would increase the lethality of curcumin and sildenafil in colorectal cancer cell lines in vitro and in vivo. In the current study, we have shown that with the [2μM curcumin + 2μM sildenafil + 2μM regorafenib] drug combination reduces of cyto-protective proteins, enhances cytotoxicity and creates a carnage of CRC cells in a greater than additive in vitro. The combination also suppressed growth of colon cancer tumors in vivo, when compared to curcumin and sildenafil alone. In addition we have shown that the [2μM curcumin + 2μM sildenafil + 2μM regorafenib] drug combination can modulate immune checkpoint proteins in vitro. These results suggest that this drug combination may enhanced the anti-tumor efficacy of anti-PD-1 and anti-CTLA4 antibodies.
36

Synthesis and Biological Evaluation of Novel Resveratrol and Combretastatin A4 Derivatives as Potent Anti-Cancer Agents

Madadi, Nikhil Reddy 01 January 2014 (has links)
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 limited bioavailability of resveratrol, can be improved by synthesizing analogs which would be glucuronidated at a lower rate than resveratrol itself. We demonstrated that ST-05 and ST-12(a) exhibit lower glucuronidation profiles when compared to resveratrol and that these synthesized stilbenoids likely represent useful scaffolds for the design of efficacious resveratrol analogs. We have also initiated a new discovery program to identify selective CB1 and CB2 receptor ligands from a library of novel stilbene scaffolds structurally related to the resveratrol molecule. From the screened resveratrol analogs, two compounds were identified as selective CB2 and CB1 ligands. Compound ST-179 had 47-fold selectivity for CB2 (Ki = 284 nM) compared to CB1, while compound ST-160 was 2-fold selective for CB1 (Ki = 400 nM) compared to the CB2 receptor. These structural analogs have the potential for development as novel cannabinoid therapeutics for treatment of obesity and/or drug dependency. Combretastatin A4 (CA-4) is one of the most potent antiangiogenic and antimitotic agents of natural origin. However, CA-4 suffers from chemical instability due to cis-trans isomerism in solution. To circumvent this problem, we have developed a facile procedure for the synthesis of novel 4,5-diaryl-2H-1,2,3-triazoles as CA-4 analogs to constrain the molecule to its cis-configuration. Twenty three triazoles were prepared as CA-4 analogs and submitted for anticancer screening. Among these CA-4 analogs, ST-467 and ST-145(b) can be considered as lead anticancer agents from this series, and further investigation against various cancer cell types in vivo with this class of compound may provide novel therapeutic avenues for treatment.
37

Enzyme Catalyzed and Ultrasound Assisted Transformation of Selected Pollutants

tan, yi 17 February 2017 (has links)
The widespread use of synthetic drugs and as feed additives has resulted in the release of large amounts of biologically active chemicals into the environment. Exposure to environmentally relevant concentrations of chemicals can have severe effects on human health. Therefore, effective degradation of these synthetic, biologically active compounds is of paramount importance. Diphenhydramine (DPH) has been selected as a target compound for ultrasound remediation. The results demonstrated that ultrasound-induced degradation has potential applications in managing aqueous media contaminated with DPH. Atorvastatin and roxarsone have been selected as representative substrates for chloroperoxidase (CPO) catalyzed transformation of pollutants. These studies demonstrate atorvastatin and roxarsone can be degraded efficiently by CPO. The transformation products of each compound were identified and the mechanisms of CPO catalysis postulated. This study provides a foundation for assessing the feasibility of applying CPO in the remediation of water and soil contaminated with pharmaceuticals and feed additives.
38

Bulldog in Blue and Gold

Brown, Stacy D. 01 April 2017 (has links)
No description available.
39

I Liked That Song Before It Was Popular

Brown, Stacy D. 01 July 2014 (has links)
No description available.
40

Random Mutagenesis of the Aspergillus Oryzae Genome Results in Fungal Antibacterial Activity

Leonard, Cory A., Brown, Stacy D., Hayman, James Russell 09 July 2013 (has links)
Multidrug-resistant bacteria cause severe infections in hospitals and communities. Development of new drugs to combat resistant microorganisms is needed. Natural products of microbial origin are the source of most currently available antibiotics. We hypothesized that random mutagenesis of Aspergillus oryzae would result in secretion of antibacterial compounds. To address this hypothesis, we developed a screen to identify individual A. oryzae mutants that inhibit the growth of Methicillin-resistant Staphylococcus aureus (MRSA) in vitro. To randomly generate A. oryzae mutant strains, spores were treated with ethyl methanesulfonate (EMS). Over 3000 EMS-treated A. oryzae cultures were tested in the screen, and one isolate, CAL220, exhibited altered morphology and antibacterial activity. Culture supernatant from this isolate showed antibacterial activity against Methicillin-sensitive Staphylococcus aureus, MRSA, and Pseudomonas aeruginosa, but not Klebsiella pneumonia or Proteus vulgaris. The results of this study support our hypothesis and suggest that the screen used is sufficient and appropriate to detect secreted antibacterial fungal compounds resulting from mutagenesis of A. oryzae. Because the genome of A. oryzae has been sequenced and systems are available for genetic transformation of this organism, targeted as well as random mutations may be introduced to facilitate the discovery of novel antibacterial compounds using this system.

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