Pharmacology, Toxicology and Environmental Health Commons^™

Excess No Stabilizes The Luminal Domain Of Stim2 In A Cys-Specific Manner Thereby Regulating Basal Calcium Homeostasis And Store-Operated Calcium Entry, Matthew Novello

Electronic Thesis and Dissertation Repository

Stromal-interaction molecule 2 (STIM2) is an endoplasmic reticulum (ER) membrane-inserted Ca²⁺-sensing protein which, together with the plasma membrane Ca²⁺ channel Orai1, regulates basal Ca²⁺ homeostasis and store-operated Ca²⁺ entry (SOCE). Recent evidence suggests that S-nitrosylation, which is the covalent attachment of a nitric oxide (NO) moiety to a cysteine thiol, can attenuate the function of the paralog STIM1 protein. Compared to STIM1, STIM2 also functions as a basal Ca²⁺ homeostatic feedback regulator. Therefore, the objective of my study was to evaluate the susceptibility of STIM2 to S-nitrosylation and the effects that this …

The Wet Bridge Transfer System: An Novel In Vitro Tool For Assessing Exogenous Surfactant As A Pulmonary Drug Delivery Vehicle, Brandon J. Baer

Western Research Forum

Background:

Due to its complex branching structure, direct drug delivery to the remote areas of the lung is a major challenge. Consequently, most therapies, such as those treating pulmonary infection and inflammation, must utilize large systemic dosing, with the potential for adverse side effects. A novel alternative strategy is to use exogenous surfactant, a material capable of distributing throughout the lung, as a pulmonary drug delivery vehicle.

Objective:

Utilize an in vitro transferring system to assess exogenous surfactant (BLES) as a pulmonary delivery vehicle for different therapeutics.

Methods:

An in vitro technique was developed to simultaneously study surfactant delivery and …

Developing Novel Therapeutics For Bacterial Lung Infections, Brandon J. Baer, Ruud Veldhuizen, Cory Yamashita

Western Research Forum

Background: Bacterial lung infections are leading causes of death worldwide. Unfortunately, increasing resistance to antibiotics and the inflammation often accompanying these infections are leading to poor outcomes despite antibiotic intervention. Complicating treatment further, the tree-like branching structure of the lung makes drug delivery to distal sites of infection difficult. Our research aims to address these challenges by developing new therapeutics and new tools to improve and assess drug delivery, bacterial killing and inflammation. Our therapy combines host defense peptides, which have been shown to kill antibiotic-resistant bacteria and down regulate inflammation, with a pulmonary vehicle, exogenous surfactant, that can improve …

Cadmium Accumulation And Distribution In Lettuce And Barley, Fardausi Akhter

Electronic Thesis and Dissertation Repository

Cadmium (Cd) is a non-essential trace element and its environmental concentrations are increasing due to human activities. Edible plants can accumulate high concentrations of Cd, which could be toxic to humans. Understanding how and where Cd is stored in plants is important for ensuring lower concentration of Cd in the food. In this thesis, the accumulation and distribution of Cd in three agricultural plants, namely lettuce (Lactuca sativa L.), barley (Hordeum vulgare L.) and radish (Raphanus sativus L.), were investigated with a focus on the potential mechanisms involved in the localization of Cd in the root. The …

Human Equilibrative Nucleoside Transporter Subtype 1: Structure-Function Analysis Using Cysteine Mutagenesis And Thiol Modifying Techniques, Jamie Park

Electronic Thesis and Dissertation Repository

Human equilibrative nucleoside transporter 1 is the main mediator of bi-directional nucleoside flux and is found ubiquitously. Inhibitor and substrate interactions with ENT1 are known to be affected by cysteine-modifying reagents. Our aim was to investigate the importance of cysteine residues in hENT1 function and identify which residues were sensitive to thiol modification for further application of cysteine scanning mutagenesis on extracellular loop 5. Transporter function was assessed by the binding of [³H]NBMPR and the cellular uptake of [³H]2-chloroadenosine. Treatment of hENT1 with the neutral sulfhydryl-modifier methyl methanethiosulfonate (MMTS) enhanced [³H]NBMPR binding but decreased …

Regulation Of G Protein Signaling By Goloco Motif Containing Proteins, Peishen Zhao

Electronic Thesis and Dissertation Repository

Signal transduction via heterotrimeric G proteins in response to transmembrane G protein-coupled receptors plays a central aspect in how cells integrate extracellular stimuli and produce biological responses. In addition to receptor-mediated activation of heterotrimeric G proteins, during the last few decades, accessory proteins have been found to regulate G protein activity via different mechanisms. Several proteins have been identified that contain multiple G protein regulatory domains. Using various molecular and biochemical approaches, we have characterized the effects of two such proteins, G18 and RGS14, on G protein activity. Both proteins contain a second G protein binding domain in addition to …