Macromolecular Substances Commons^™

Methamphetamine-Induced Dna Double-Stranded Breaks: The Impact Of The Dopamine Transporter And Insights Into The Mechanisms Of Dna Damage In Mouse Neuro 2a Cells, Lizette Couto

Dissertations, Theses, and Capstone Projects

Methamphetamine (METH) abuse remains a global health concern, with emerging evidence highlighting its genotoxic potential. In the central nervous system METH enters dopaminergic cells primarily through the dopamine transporter (DAT), which controls the dynamics of dopamine (DA) neurotransmission by driving the reuptake of extracellular DA into the presynaptic neuronal cell. Additional effects of METH on the storage of DA in synaptic vesicles lead to the dysregulated cytosolic accumulation of DA. Previous studies have shown that after METH disrupts intracellular vesicular stores of DA, the excess DA in the cytosol is rapidly oxidized. This generates an abundance of reactive oxygen species …

Nanodiscs: A Novel Approach To The Study Of The Methionine Abc Transporter System, Michael T. Winslow

Master's Theses

Membrane transporter proteins play the vital role of moving compounds in and out of the cell and are essential for all living organisms. ATP Binding Cassette (ABC) family transporters function both as importers and exporters in prokaryotes. MetNI is an E. coli Type I ABC transporter responsible for the uptake of methionine into the cytosol from the cell periplasmic space through the cell membrane to maintain intracellular methionine pools. ABC transporters, like other membrane proteins, are most often mechanistically and structurally studied in vitro, solubilized by detergents. However, detergent micelles may affect the conformational changes of membrane proteins relative to …

Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino

Biological Sciences Undergraduate Honors Theses

This honors thesis aims to investigate the reusability and performance of cell coatings for cell therapy applications. Cell therapy, which involves the use of human cells to repair or replace damaged tissues, holds immense potential for medical advancements. However, ensuring the survival and functionality of transplanted cells remains a significant challenge. We focused on studying the effectiveness of coatings applied to cells for improved cell growth and viability. The research project involved the preparation of the coatings using a layer-by-layer method and the subsequent seeding of cells. The coated cells were then subjected to a series of experiments to assess …

The Developing Effects Of Potassium Ferricyanide On Tetrahymena, Katelyn Coronell

Whittier Scholars Program

Potassium Cyanide is a highly toxic chemical asphyxiant that interferes with the body's ability to use oxygen, typically by directly affecting the body by ingestion, inhalation, skin contact, or eye contact(CDC, 2011). Due to its high toxicity, the main effect that leads to the downfall of the organism begins with the cessation of aerobic metabolism; it does this by cyanide binding to the ferric ions and inhibiting cytochrome oxidase within the mitochondria (Zhang, 2015). There are no physical dangers the substance causes. Although, there are many chemical dangers. If used at temperatures higher than 70℉ The substance may produce toxic …

Second Generation Phenyloxadiazolyl Methyl Sulfones For Thiol-Specific Bioconjugations, Guillaume Dewaele-Le Roi

Dissertations, Theses, and Capstone Projects

The role of antibody-based molecular agents for diagnosis and therapy of cancer has expanded significantly over the past decades. However, most of these constructs are synthesized using traditional bioconjugation methods based on the random ligations between the molecular cargo and lysine residues within the protein. These non-specific approaches can create poorly defined conjugates with suboptimal immunoreactivity and in vivo performance while Site-specific approaches to antibody bioconjugation based on ligations between maleimides and free cysteine residues have long stood as attractive alternatives. Yet the inherent instability of the thiol-maleimide linkage has fueled the search for new, more stable thiol-reactive prosthetic groups. …

Application Of Mass Spectrometry For The Characterization Of Synthetic Oligomers And Natural Lignin, Poorya Kamali

Theses and Dissertations--Chemistry

As part of the ongoing effort to substitute finite fuel and chemical resources with renewable ones, biomass is emerging as one of the most promising sources. Biomass consists of three main components of cellulose, hemicellulose, and lignin. Traditionally, cellulose has been used extensively in pulping industry, while lignin has been considered waste and is burned to generate heat. Lignin, a complex aromatic polymer component of biomass, has the potential to be used as a source of aromatic chemicals and pharmaceutical synthons. The recalcitrant nature of lignin, the lack of effective lignin breakdown methods and analytical techniques to analyze it are …

Polymeric Chloroquine In Metastatic Pancreatic Cancer Therapy, Rubayat Islam Khan

Theses & Dissertations

Hydroxychloroquine (HCQ) is an established drug that has been used for the treatment of multiple diseases, including malaria, rheumatoid arthritis, and lupus erythematosus. Several recently published studies have highlighted its beneficial use in various types of cancers, and a plethora of clinical trials are currently evaluating its use in cancer therapies, wherein some of the results look promising. The preclinical studies to date suggest HCQ can work effectively in conjunction with traditional cancer treatments, as it has been shown to sensitize tumor cells to a wide range of chemotherapeutic agents. Polymeric HCQ (PCQ), a macromolecular multivalent version of HCQ, has …

Frontiers In The Self-Assembly Of Charged Macromolecules, Khatcher O. Margossian

Doctoral Dissertations

The self-assembly of charged macromolecules forms the basis of all life on earth. From the synthesis and replication of nucleic acids, to the association of DNA to chromatin, to the targeting of RNA to various cellular compartments, to the astonishingly consistent folding of proteins, all life depends on the physics of the organization and dynamics of charged polymers. In this dissertation, I address several of the newest challenges in the assembly of these types of materials. First, I describe the exciting new physics of the complexation between polyzwitterions and polyelectrolytes. These materials open new questions and possibilities within the context …

A Study Of Dextran As A Macromolecular Crowding Agent, Katherine Morgan

Honors Theses

Deoxyribonucleic acid (DNA) is the hereditary material in all living organisms. According to the Watson and Crick model, DNA exists as two long strands coiled into a double helix. However, DNA has been found to have the potential to exist in secondary forms known as G-Quadruplexes and i-motifs. I-motifs (intercalated-motif or iM) are formed under acidic conditions when sets of cytosines pair with protonated cytosines and are looped around each other. The pKa value for iMs in dilute solutions is approximately 6.5, but iMs can potentially exist at a higher, physiological pH value under crowded conditions. Within the interior of …

The Development Of Polymeric Dexamethasone Prodrug Nanomedicines For The Treatment Of Lupus Nephritis, Zhifeng Zhao

Theses & Dissertations

Lupus nephritis (LN) is a significant cause of morbidity and mortality among lupus patients. Glucocorticoids (GCs) are uniformly used in clinical LN management. Their notorious toxicities, however, have hampered the long-term clinical application. To circumvent GCs’ adverse effects while maintaining their potent therapeutic efficacy, we have developed a micelle-forming polyethylene glycol (PEG)-conjugated dexamethasone prodrug (ZSJ-0228), which could passively target the inflamed kidney in NZB/W F1 lupus-prone mice. It was found that monthly ZSJ-0228 treatment for five months significantly reduced the incidence of nephritis in NZB/W F1 mice with an improved survival rate. Unlike the dose equivalent daily dexamethasone treatment, long-term …

Succinylated Polyethylenimine Gene Delivery Agents For Enhanced Transfection Efficacy, Md. Nasir Uddin

Theses and Dissertations--Chemistry

Gene therapy aims to treat patients by altering or controlling gene expression. Today, most clinical approaches are viral-based due to their inherent gene delivery activity. However, there is still a significant interest in nonviral alternatives for gene delivery, particularly synthetic lipids and polymers, that do not suffer the immunogenicity, high cost, or mutagenesis concerns of viral vectors. Polymeric vectors are of particular interest due to the ability to further tune the polymer properties through the incorporation of additional functional units such as targeting ligands or shielding domains. Polyethylenimine (PEI), a highly cationic polymer, is often considered a benchmark for polymer-based …

Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang

Dissertations, Theses, and Capstone Projects

Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …

Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky

Open Educational Resources

The goal of this preparatory textbook is to give students a chance to become familiar with some terms and some basic concepts they will find later on in the Anatomy and Physiology course, especially during the first few weeks of the course.

Organization and functioning of the human organism are generally presented starting from the simplest building blocks, and then moving into levels of increasing complexity. This textbook follows the same presentation. It begins introducing the concept of homeostasis, then covers the chemical level, and later on a basic introduction to cellular level, organ level, and organ system level. This …

Synthesis And Self-Assembly Of Amphiphilic Block Copolymers For The Fabrication Of Non-Spherical Polymersomes, Tamuka Chidanguro

Dissertations

Polymersomes, also known as polymer vesicles, have gained a lot of interest over the past two decades. These hollow spherical systems are made via the self-assembly of amphiphilic block copolymers and have found use in a range of areas from drug delivery, to cellular models, to nanoreactors. Their hollow nature allows them to carry hydrophilic cargo in their inner compartment and hydrophobic cargo in their membrane. Over the last decade, increasing efforts have focused on controlling the morphology of polymersomes. Research has shown that polymersome morphology plays an important role for instance in drug delivery, where tubular or rod-like vesicles …

Biochemical Characterization Of Small Molecule Inhibitor Binding On A Ras Related Gtpase And Its Effector Interactions, Djamali Muhoza

Graduate Theses and Dissertations

The Ras superfamily of GTPases has 167 proteins that are involved in various cellular processes such as proliferation, transformation, migration, and inhibition of cell death. Mutations, abnormal expression, and function of these proteins are observed in many diseases, including several forms of cancer. Even though these GTPases were among the first discovered oncogenes, no successful Ras drug candidate has successfully passed clinical trials. Drugs targeting these proteins have failed mainly because of the complexity of their regulation, their high affinity to GTP, and their structure’s dynamic nature. Recently, novel promising targeting approaches have renewed interest in the Ras drug discovery …

Applied Molecular Dynamics: From Targeting Viral Helicases, To Understanding The Interactions Of Cucurbituril Complexes In Ionic Solutions, Bryan Raubenolt

University of New Orleans Theses and Dissertations

Molecular Dynamics simulations are a highly useful tool in helping understand the fundamental interactions present in a variety of chemical systems. The work discussed here illustrates it’s use in determining the conformational dynamics of the Zika and SARS-Cov-2 helicase in a physiological environment, largely in an effort to discover inhibitors capable of rendering the protein inert. Additionally, we show how it can be used to understand paradoxical trends in the anion-induced precipitation of Cucurbituril cavitands.

Viral helicases are motor proteins tasked with unwinding the viral dsRNA, a crucial step in preparing the strand to be translatable by host cells. By …

Assessment Of The Use Of Low Molecular Weight Diblock Copolymers For The Formation Of Stable, Tunable Droplet Interface Bilayers, Joseph Tawfik

Masters Theses

This thesis presents the use of diblock copolymers, poly(butadiene)-b-poly(ethylene oxide) (PB_m PEO_n) and poly(isoprene)-b-poly(ethylene oxide) (PI_mPEO_n), as amphiphilic molecular building blocks for the formation of synthetic polymer bilayer membranes using the droplet interface bilayer (DIB) technique. The DIB technique makes use of the self-assembly of amphiphilic macromolecules along oil-water droplet interfaces that can then be physically connected for the construction of liquid supported macromolecular bilayers at the droplet interface. These bilayer membranes are capable of hosting both naturally occurring and synthetic protein channels. This technique has been used to form synthetic bilayer membranes …

Determining The Link Between Advanced Glycation Endproducts (Ages), Feeding, And Metabolism, Lauren Wimer

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Reactive a-dicarbonyls (a-DC’s), such as methylglyoxal (MGO), are unavoidable metabolites generated during glycolysis that accumulate with age and have been linked with chronic age-related metabolic diseases such as Diabetes Mellitus. Diabetes Mellitus is generally characterized by peripheral neuropathy and sustained hyperglycemia. Chronic hyperglycemia leads to an increase in glycolysis and a downstream increase in reactive a-DC’s. The human body has a natural method of detoxifying these a-DC’s. Glycolytic cells have enzymes which can detoxify a-DC’s, but if overwhelmed, a-DC’s can accumulate and react non-enzymatically with proteins, lipids and DNA to yield a group of molecules called advanced glycation end-products (AGEs). …

Synthesis And Characterization Of Pamam-Fatty Acid “Janus-Type” Dendritic Hybrids For Biomedical Applications, Abigail Grace Barker

Honors Theses

Janus dendrimers are amphiphilic macromolecules that have shown promising potential in the biomedical field. Due to their unique structure and properties, these branched block copolymers have the ability to self-assemble into bioinspired spherical nanoaggregates. Because they possess a hydrophobic and hydrophilic moiety, these aggregates show potential as drug delivery systems that can transport both hydrophobic and hydrophilic drugs. However, many of the proposed dendrimer systems suffer from certain weaknesses that hinder their practical usage as clinical treatment options. Some of these shortcomings include specificity, solubility, size, surface charge, and mechanical properties. To combat these problems, we synthesized and characterized a …

Development Of Hyaluronic Acid-Derived Macromolecular Agents For Multimodal Imaging Probes And Nanomedicine, William M. Payne

Theses & Dissertations

Cancer, one of the most challenging maladies facing modern medicine, is a complex family of diseases that requires a multifaceted treatment regime. In recent years, increased research effort has been placed on the development of nanoscale formulations as a potential method to improve therapeutic efficacy and offer better treatment. Both drug formulation and biomedical imaging has benefitted from the development of new, nanoscale agents. Hyaluronic Acid (HA), a naturally occurring glycosaminoglycan, is a promising platform for the development of new drug delivery systems. Furthermore, hyaluronic acid is the principal ligand for the cell surface receptor CD44, which is overexpressed on …