Pharmacology, Toxicology and Environmental Health Commons^™

Computational Analysis Of Type 3 Iodothyronine Deiodinase: Potential Inhibitors, Substrate Binding, And Dimer Structure, Eric Scott Marsan

Chemistry & Biochemistry Theses & Dissertations

Thyroid hormones (THs) in mammalian tissues are crucial for development and maintaining metabolic homeostasis. Iodothyronine deiodinases (Dios) remove iodines from THs by a selenocysteine (Sec) residue, which either activates or inactivates them. Halogen bonding (XB) has been proposed to describe the interaction between the Se and I atoms of the T4-Dio complex. Disruption of TH homeostasis by xenobiotics, such as polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) can cause deleterious effects on the endocrine system. Experimental studies have indicated that PBDEs and PCBs could disrupt TH homeostasis by inhibiting Dio through XB formation. However, no current quantitative study exists …

Effects Of Carboxylated Nanodiamonds On Macrophages During And After Differentiation, Maisoun E. Bani Hani

Biological Sciences Theses & Dissertations

Nanodiamonds (ND) are a carbon-based nanomaterial that are increasingly being proposed for developing novel imaging techniques, as carriers of biomolecules and therapeutic drugs, as coatings for implants, and for other biomedical applications. The exceptional chemical, mechanical, and optical properties of ND make this material suitable in a wide range of fields. The application of ND in the biomedical field is attractive but requires more in-depth investigation into the safety of ND and its interactions with different cells and systems. The effects of ND on the immune system are not fully understood or investigated and there are several controverting reports regarding …

2-Aminoethoxydiphenyl Borate As A Prototype Drug For A Group Of Structurally Related Calcium Channel Blockers In Human Platelets, Yuliya Dobrydneva, Christopher J. Abelt, Beth Dovel, Celina M. Thadigiri, Roy L. Williams, Peter F. Blackmore

Chemistry & Biochemistry Faculty Publications

We have synthesized a series of 2-aminoethoxydiphenyl borate (2-APB, 2,2-diphenyl-1,3,2-oxazaborolidine) analogs and tested their ability to inhibit thrombin-induced Ca²⁺ influx in human platelets. The analogs were either synthesized by adding various substituents to the oxazaborolidine ring (methyl, dimethyl, tert-butyl, phenyl, methyl phenyl, and pyridyl) or increasing the size of the oxazaborolidine ring to seven- and nine-membered rings. NMR analysis of the boron-containing analogs suggests that each of them exist as a ring structure through the formation of an N -> B coordinate bond (except for the hexyl analog). The possibility that these boron-containing compounds formed dimers was also …

Development Of Single Nanoparticle Optical Assays For Imaging Single Living Cells, William John Brownlow

Chemistry & Biochemistry Theses & Dissertations

Multi-drug resistance (MDR) has been reported in both prokaryotes and eukaryotes; the pathogenic gram-negative bacteria Pseudomonas aeruginosa can extrude a variety of structurally and functionally diverse substrates via a number of membrane transport systems leading to MDR. We have developed a novel nanoparticle assay to characterize both the membrane transport system composed of the MexAB-OprM efflux pump and the membrane permeability induced by antibiotics. Gold (Au) and silver (Ag) nanoparticles were investigated for use as probes to explore membrane transport in P. aeruginosa.

The surface plasmon absorption (color) of Au nanoparticle solutions was found to change in the presence …

Bioprospecting, Philip A. Reed

STEMPS Faculty Publications

The article discusses that the product applications of bioprospecting are almost limitless. This area of biotechnology has been labeled bioprospecting, and it is a practice that is creating worldwide controversy. Defined simply, bioprospecting is "scientific research that looks for a useful application, process, or product in nature." However, as with most biotechnologies, the definition does not address the complexities of bioprospecting. Archeologists are finding that some biotechnologies, such as the use of herbs for medicine and the use of fermentation and yeast in food products, date back 5,000 to 10,000 years (De Miranda, 2004). The four main categories of biotechnologies …

Investigations On The Use Of Ion Mobility Spectrometry For Clinical Chemistry Applications, Henri Parson Patten

Theses and Dissertations in Biomedical Sciences

The major objective of this research is to examine ion mobility spectrometry as a rapid screening tool for specific application to clinical chemistry research and laboratory use. Methodology was developed for target analytes representing several classes of physiologically active substances, including anesthetics, illicit drugs, and their metabolites. The IMS characteristics of animal tissues and other compounds such as amino acids and proteins were determined. Quality assurance and control procedures were developed for specific quality data objectives. Criteria were established relating to use of IMS for assessing the precision and accuracy of data, qualitative screening, and semi-quantitative analyses.

It was found …

Evaluation Of Toxicity, Bioavailability And Speciation Of Lead, Zinc And Cadmium In Mine/Mill Wastewaters, Mujde Erten-Unal, Bobby G. Wixson, Nord Gale, Jerry L. Pitt

Civil & Environmental Engineering Faculty Publications

The toxicity of common compounds of lead, cadmium and zinc was evaluated in waters similar to that found in the world's largest lead producing area in Missouri. Static, acute toxicity tests were performed using fathead minnows (Pimephales promelas) and water fleas (Daphnia magna) respectively. Test organisms were subjected to varying amounts of sulfide, carbonate, chloride and sulfate salts of lead, zinc and cadmium mixed in hard, alkaline waters typical to this region. Median lethal concentrations were calculated using nominal versus measured metal concentrations. Measured metal concentrations included four different metal fractionation (extraction/filtration) techniques at different pH …

Effect Of Cocaine On Rabbit Renin Angiotensin System: Cocaine Detection In Adult And Fetal Tissue And Adult Plasma Using Ion Mobility Spectrometry, Barbara Belinda Guinn

Biological Sciences Theses & Dissertations

Ion mobility spectrometry (IMS) was used to detect cocaine and/or the metabolite ecgonine methyl ester (EME) in tissue and plasma samples from male, maternal, and fetal New Zealand White (NZW) rabbits. EME was consistently detected in all adult plasma samples 5 minutes after the injection of cocaine hydrochloride (cocaine•HCI, 2 mg/kg). EME was also in the liver, kidneys, testicles, and ovaries. Five minutes after the injection of cocaine•HCI, the male arterial pressure (MAP) increased from a mean control value of 79 ± 3.2 mmHg to 88 ± 4.1 mmHg, and the pCO₂ increased from a control value of28 ± …

In Situ Regulation Of Cytosolic Phospolipase A₂, Beverly A. Rzigalinski

Theses and Dissertations in Biomedical Sciences

The 85 kDa cytosolic phospholipase A₂ (cPLA₂) is an agonist-responsive effector for intracellular signal transduction through the arachidonate cascade. In vitro studies have demonstrated that this enzyme is regulated by sub-micromolar calcium and is specific for arachidonate as the sn-2 fatty acyl group of phospholipid substrates. However, very little data is available regarding in situ mechanisms which govern the activity of cPLA₂. The primarily objective of these studies was to develop an in situ system for the study of cPLA₂, and investigate mobilization of arachidonate during signal transduction events.

Dimethylsulfoxide differentiation of the …

A Biochemical Study Of Gossypol And Lactate Dehydrogenase X Binary Interactions, Patricia Brown Ravenell

Theses and Dissertations in Biomedical Sciences

The goal of this project was to study the mechanism of action of gossypol through its (a) binary interaction with native and trypsin digested lactate dehydrogenase-X (LD-X), a sperm-specific isozyme, and (b) its binding in vitro in primary cultures of spermatogenic cells. Mouse LD-X was cleaved with trypsin before and after treatment with gossypol. This was followed by high performance chromatography (HPLC) separation of the LD-X tryptic peptide fragments to observed alterations in separation patterns as indicators of intramolecular disturbance in the enzyme molecule. Definite alterations in peptide fragment peaks were observed in the presence of gossypol and suggest conformational …

The Effects Of Tri-O-Cresyl Phosphate On 2',3'-Cyclicnucleotide-3'-Phosphohydrolase Activity In Neural And Non-Neural Tissue Of The Rat, Mark K. Schlager

Chemistry & Biochemistry Theses & Dissertations

A total of 44 Long-Evans rats received 5.7 g/kg tri-O-cresyl phosphate (TOCP) orally every 3 days for 6 days. A second group of 13 rats received 4.6 g/kg orally every 3 days for 6 days. Animals were administered atropine sulfate (10 mg/kg) intraperitoneally every 6 hours or as needed to alleviate cholinergic symptoms. Ten control animals were given corn oil orally. Eight rats (18%) survived the 5.7 g/kg dose regimen and 5 rats (38%) survived the 4.6 g/kg dose regimen. Surviving rats were killed at 30-33 days post-dose. Signs of delayed neuropathy included ataxia and motor impairment.

The CNP activity …

Sulfatides As Opiate Receptors: An Evaluation Of The Opiate Binding Potential Of Sulfogalactosylgylcerolipid, Darby Geoghegan Hand

Chemistry & Biochemistry Theses & Dissertations

Cerebroside sulfate (CS) has recently been shown to bind opiate drugs in a pharmacologically relevent manner and therefore satisfy the structural requirements of an opiate receptor. Seminolipid (SGG), a novel sulfated galactosyl. glycerolipid that has been isolated from the testes of a variety of mammals, may be viewed as a structural analog of CS. In view of this structural similarity, it is reasonable to presume that SGG may also bind opiate drugs. The isolation of SGG from boar testes was accomplished using silica gel dry column chromotography with a chloroform: methanol water solvent system. The structure and purity of the …