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Articles 1591 - 1620 of 15526

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Evolution Of A Self-Renewing, Participant-Centered Workshop Series In Bmb Assessment, Ludmila Tyler, Peter J. Kennelly, Shelly Engelman, Kirsten F. Block, Jennifer C. Bobenko, Jaclyn Catalano, Jesica A. Jones, Margaret I. Kanipes-Spinks, Yang Mooi Lim, Jennifer Loertscher, Tejiri Olafimihan, Hailey Reiss, Territa L. Upchurch-Poole, Yufeng Wei, Kimberly J. Linenberger Cortes, Victoria Del Gaizo Moore Jan 2024

Evolution Of A Self-Renewing, Participant-Centered Workshop Series In Bmb Assessment, Ludmila Tyler, Peter J. Kennelly, Shelly Engelman, Kirsten F. Block, Jennifer C. Bobenko, Jaclyn Catalano, Jesica A. Jones, Margaret I. Kanipes-Spinks, Yang Mooi Lim, Jennifer Loertscher, Tejiri Olafimihan, Hailey Reiss, Territa L. Upchurch-Poole, Yufeng Wei, Kimberly J. Linenberger Cortes, Victoria Del Gaizo Moore

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

We present as a case study the evolution of a series of participant-centered workshops designed to meet a need in the life sciences education community—the incorporation of best practices in the assessment of student learning. Initially, the ICABL (Inclusive Community for the Assessment of Biochemistry and Molecular Biology/BMB Learning) project arose from a grass-roots effort to develop material for a national exam in biochemistry and molecular biology. ICABL has since evolved into a community of practice in which participants themselves—through extensive peer review and reflection—become integral stakeholders in the workshops. To examine this evolution, this case study begins with a …

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Development Of Microfluidic Thermal Gel Electrophoresis For Biological Analysis, Mario Ambrocio Cornejo Jan 2024

Development Of Microfluidic Thermal Gel Electrophoresis For Biological Analysis, Mario Ambrocio Cornejo

Wayne State University Dissertations

ABSTRACTDEVELOPMENT OF MICROFLUIDIC THERMAL GEL ELECTROPHORESIS FOR BIOLOGICAL ANALYSIS by MARIO AMBROCIO CORNEJO May 2024 Advisor: Dr. Thomas H. Linz Major: Chemistry (Analytical Chemistry) Degree: Doctor of Philosophy The molecular biology that takes place within cells is vital to the over function of an organism. Healthy cellular function is crucial to a wide web of interconnected processes that need to be balanced and regulated. When these processes become abnormal, disease states are developed. The mapping of biological networks has led to the development of gene therapy and more accurate diagnostic tests. However, there are still vital biomolecules that due to …

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Exploiting Light To Probe Biological Processes, Madeline Denison Jan 2024

Exploiting Light To Probe Biological Processes, Madeline Denison

Wayne State University Dissertations

Metal complexes have many advantages as biochemical tools due to their rich photophysical properties and unique geometry. Metal-based complexes are commonly reported as emissive probes or photoactivatable biological agents. Long emission lifetimes of metal complexes allow for the use of lifetime gating which eliminates autofluorescence found in assays, a distinct advantage over short-lived organic fluorophores. This work utilizes this powerful technique to generate reversible, emissive probes for monitoring CYP3A4 active site occupancy. In addition to the emissive properties of metals, metals can also be used as photodynamic therapy (PDT) and photochemotherapy (PCT) agents. These light-activated strategies provide important spatiotemporal control …

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Visible Light Photocatalysis With Quantum Dot Gel For Organic Synthesis, Daohua Liu Jan 2024

Visible Light Photocatalysis With Quantum Dot Gel For Organic Synthesis, Daohua Liu

Wayne State University Dissertations

This dissertation presents metal chalcogenide quantum dots (QDs), a group of emerging visible light photocatalysts, for unique organic chemical transformations that are impossible using conventional molecular photocatalysts. The first part of this dissertation focuses on the comparison between ligand-capped CdS QD and CdS gel. CdS QD gel is a three-dimensional network of interconnected QD. CdS gels were found to show more facile charge transfer with substrates than QDs, due to the partial removal of ligands from its surface during gelation. Our study showed that the photocatalytic activity of CdS gels was indeed superior to trioctylphosphine (TOP)- and thioglycolic acid (TGA)-capped …

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Chemoselective Reduction Of Dicarboxylic Acids Via Iridium Catalyzed Hydrosilylation, Linda Lallawmsangi Jan 2024

Chemoselective Reduction Of Dicarboxylic Acids Via Iridium Catalyzed Hydrosilylation, Linda Lallawmsangi

Chemistry & Biochemistry Theses - Archive

Reduction of esters to aldehydes poses a challenge since the resulting aldehydes are often more reactive than the initial esters toward nucleophilic hydride-reducing agents. Although bulky, more controllable reducing agents such as lithium tri-tert-butoxyaluminum hydride or diisobutylaluminum hydride (DIBAL-H) have been developed, they are hazardous, sensitive to moisture and air, needing strict reaction conditions, and unsuitable with a wide range of functional groups. We present the design of an iridium-catalyzed chemoselective hydrosilylation method for dicarboxylic imides, followed by hydrolysis to eliminate the amide and yield aldehydes. This approach offers versatility in general reduction chemistry, holds promise for application …

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Validating Machine And Human Decision-Making In Forensic Fire Debris Analysis, Frances A. Whitehead Jan 2024

Validating Machine And Human Decision-Making In Forensic Fire Debris Analysis, Frances A. Whitehead

Graduate Thesis and Dissertation 2023-2024

This work presents a background on the chemical complexity of fire debris analysis, including an ever-present matrix of pyrolysis products as the catalyst that led to the creation of the National Center for Forensic Science's Fire Debris Database. A selection of these 1,000+ casework-relevant ground truth samples was used to create two newly proposed analyst workflows to connect the current method of categorical reporting with evaluative reporting practices reflective of the strength of the evidence. Both workflows use linear sequential unmasking to help mitigate bias, a discrete scoring system for quantification of the analysis, and receiver operating characteristic (ROC) curves …

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Density Functional Studies Of Molecular Separation And Charge Transport, Timothy Quainoo Jan 2024

Density Functional Studies Of Molecular Separation And Charge Transport, Timothy Quainoo

Wayne State University Dissertations

This thesis presents a series of studies which can be grouped majorly into two sections both focusing on the utilization of density functional theory techniques; Molecular electronics and Molecular separation. Molecular electronics has been anticipated to hold a great future as it seeks to apply molecular building blocks in the creation of electronic components. On the other hand, the utilization of mild conditions in chemical processes is geared toward the major goals of green chemistry as it produces less waste and is cost-effective. Thus, this dissertation tackles and answers some of the unanswered questions in literature by using theoretical methods …

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Design And Synthesis Of Aminoglycoside-Based Heparan Sulfate Mimetics For Structure-Activity Relationship Studies Of Heparan-Binding Proteins, Joseph Wakpal Jan 2024

Design And Synthesis Of Aminoglycoside-Based Heparan Sulfate Mimetics For Structure-Activity Relationship Studies Of Heparan-Binding Proteins, Joseph Wakpal

Wayne State University Dissertations

Cancer remains a formidable challenge in modern medicine, demanding innovative approaches and treatments. Among the emerging strategies, inhibiting heparanase and fibroblast growth factor 2 (FGF2) has garnered considerable attention in recent years. This dissertation presents a novel approach to designing and synthesizing a diverse library of heparan sulfate (HS) mimetics derived from aminoglycosides to study their binding to two heparin-binding proteins involved in cancer development and metastasis. Heparanase cleaves HS polysaccharide chains in the extracellular matrix (ECM) and is a regulator of aggressive tumor behavior. Clinical studies have illustrated that aberrant heparanase expression correlates with increased tumor size, amplified tumor …

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Solution Combustion Synthesis And Characterization Of Fumarolic Mineral Dolerophanite, Copper (Ii) Oxide Sulfate, Eric J. Cyganowski Jan 2024

Solution Combustion Synthesis And Characterization Of Fumarolic Mineral Dolerophanite, Copper (Ii) Oxide Sulfate, Eric J. Cyganowski

Chemistry & Biochemistry Theses - Archive

Dolerophanite Cu2OSO4 is a rare mineral found almost exclusively in the fumaroles of volcano systems and is sensitive to temperature and humidity conditions. It has a monoclinic C2/m crystal structure characterized by two-dimensional layers composed of sulfate anions dispersed amongst copper (II) oxide backbones. There has been recent interest in dolerophanite due to the magnetic properties of its Kagome-like lattice as well as its potential use as a photocatalyst or Li-ion battery electrode. Literature on the material however has been limited by the available synthesis strategies. As such, this thesis work presents a novel strategy …

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Calcium Carbonate-Based Stimuli-Responsive Microcarriers For Targeted Drug Delivery Against Oral Bacterial Infections And Development Of Glass-Free Microfluidics As An Analytical Platform, Krishantha Wijewardhane Jan 2024

Calcium Carbonate-Based Stimuli-Responsive Microcarriers For Targeted Drug Delivery Against Oral Bacterial Infections And Development Of Glass-Free Microfluidics As An Analytical Platform, Krishantha Wijewardhane

Dissertations and Theses

Dental diseases present a significant global health challenge, affecting individuals across all age groups. This spectrum of oral health issues encompasses conditions like dental caries, periodontitis (gum disease), and oral infections. In the customer discovery interviews, dental patients have raised concerns about potential drug overexposure during and after procedures, driven by fears of adverse effects, allergies, and the increasing use of antibiotics and anesthesia. Dentists are increasingly focused on minimizing opioid and steroid-based medication doses due to potential side effects and addiction risks. This study explores an innovative approach to targeted drug delivery in the dental environment using eco-friendly and …

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Structural Modification Of 4'-Aminochalcones As Α-Glucosidase Inhibitors, Emmanuel Sunday Idoko Jan 2024

Structural Modification Of 4'-Aminochalcones As Α-Glucosidase Inhibitors, Emmanuel Sunday Idoko

Chulalongkorn University Theses and Dissertations (Chula ETD)

Diabetes mellitus, one of the most predominant health problems worldwide, characterized by hyperglycemia, has attracted the attention of medicinal chemists. Although several therapeutic drugs have been developed and used clinically, diabetes continues to pose a growing threat to public health. One of the promising approaches for treating type 2 diabetes involves reducing the rate of carbohydrate hydrolysis by inhibiting the action of α-glucosidase. Over the years, chalcone analogues have been reported for their vast biological properties and as a promising antidiabetic agent. In this research, two series of 4'-aminochalcone derivatives were designed and synthesized as α-glucosidase inhibitors. Twenty-five alkylated 4'-aminochalcone …

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High Purity Silver Nano- And Micro Particles With Controllable Shapes By Polymeric Stabilizers, Natsuda Muankhajorn Jan 2024

High Purity Silver Nano- And Micro Particles With Controllable Shapes By Polymeric Stabilizers, Natsuda Muankhajorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work presents a rapid, sustainable, and efficient technique for both recovering silver microstructures from spent button batteries and fabricating flexible conductive materials. In the first phase, a green recovery method was developed using H2O2 as a reducing agent to convert silver sources into high-purity silver microstructures. The morphology of the recovered silver was controlled using polymeric stabilizers (PVP and PVA) whose molecular weights significantly influenced particle shape and aggregation. PVP promoted the formation of uniform silver microplates, while PVA yielded isotropic microspheres. The silver microstructures from the spent button batteries were converted into highly pure silver microstructures (>98%), …

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A Breast Cancer Stem Active Cobalt(Iii)-Cyclam Complex Containing Flufenamic Acid With Immunogenic Potential, Jiaxin Fang, Owamagbe N. Orobator, Chibuzor Ngozi Olelewe, Ginevra Passeri, Kuldip Singh, Samuel G. Awuah, Kogularamanan Suntharalingam Jan 2024

A Breast Cancer Stem Active Cobalt(Iii)-Cyclam Complex Containing Flufenamic Acid With Immunogenic Potential, Jiaxin Fang, Owamagbe N. Orobator, Chibuzor Ngozi Olelewe, Ginevra Passeri, Kuldip Singh, Samuel G. Awuah, Kogularamanan Suntharalingam

Chemistry Faculty Publications

The cytotoxic and immunogenic-activating properties of a cobalt(III)-cyclam complex bearing the non-steroidal anti-inflammatory drug, flufenamic acid is reported within the context of anti-cancer stem cell (CSC) drug discovery. The cobalt(III)-cyclam complex 1 displays sub-micromolar potency towards breast CSCs grown in monolayers, 24-fold and 31-fold greater than salinomycin (an established anti-breast CSC agent) and cisplatin (an anticancer metallopharmaceutical), respectively. Strikingly, the cobalt(III)-cyclam complex 1 is 69-fold and 50-fold more potent than salinomycin and cisplatin towards three-dimensionally cultured breast CSC mammospheres. Mechanistic studies reveal that 1 induces DNA damage, inhibits cyclooxygenase-2 expression, and prompts caspase-dependent apoptosis. Breast CSCs treated with 1 exhibit …

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Unusual Eluents, Small Systems, And Digital Signal Processing For Highly Efficient Greener Separations, Troy T. Handlovic Jan 2024

Unusual Eluents, Small Systems, And Digital Signal Processing For Highly Efficient Greener Separations, Troy T. Handlovic

Chemistry & Biochemistry Dissertations - Archive

Separation science is a rapidly evolving field, where routine analyses are now done at speeds and efficiencies not thought to be possible several years ago. The tangential field of green analytical chemistry is evolving at an even faster rate and can be considered to be in its infancy stage. As green analytical chemistry is better understood, the greenness of a method will be considered during standard method development just as resolution, sensitivity, and efficiency are considered now. The first portion of this dissertation focuses on the development of mathematical and pragmatic methods to minimize the analytical method greenness score, and …

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Development Of Vacuum-Assisted Headspace High-Capacity Solid-Phase Microextraction For The Determination Of Semi-Volatile Compounds From Samples At Lower Temperatures, Shannon L. Thomas, Kevin A. Schug, Colton Myers, Jason S. Herrington, Reagan L. Miller, Anush Pabley, Frank W. Foss Jan 2024

Development Of Vacuum-Assisted Headspace High-Capacity Solid-Phase Microextraction For The Determination Of Semi-Volatile Compounds From Samples At Lower Temperatures, Shannon L. Thomas, Kevin A. Schug, Colton Myers, Jason S. Herrington, Reagan L. Miller, Anush Pabley, Frank W. Foss

Chemistry & Biochemistry Dissertations - Archive

Vacuum-assisted headspace solid-phase microextraction (Vac-HS-SPME) is a method used to increase solid-phase microextraction sampling of semi-volatile organic compounds. Three studies were conducted using Vac-HS-SPME via gas chromatography - mass spectrometry (GC-MS) methods for analysis of various sample types. First, a study was performed using Vac- HS-SPME combined with a high-capacity (HC) SPME Arrow to determine the operational fundamentals and workflow necessary to achieve optimal extraction of semi-volatile compounds from a model solid matrix (Ottawa sand). The fundamentals investigated included the seals necessary to create a leak-free sampling vial under vacuum conditions; the magnitude of the vacuum exerted, and the time …

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Advanced Detection Of Sars-Cov-2 And Omicron Variants Via Mxene-Graphene Hybrid Biosensors Utilizing Nucleic Acid Probes, Jiaoli Li, Yuwei Zhang, Congjie Wei, Yanxiao Li, Zhekun Peng, Hsin Yin Chuang, Logan Pearce, Adrianus Boon, Yue-Wern Huang, Dong Hyun Kim, Risheng Wang, Chenglin Wu Jan 2024

Advanced Detection Of Sars-Cov-2 And Omicron Variants Via Mxene-Graphene Hybrid Biosensors Utilizing Nucleic Acid Probes, Jiaoli Li, Yuwei Zhang, Congjie Wei, Yanxiao Li, Zhekun Peng, Hsin Yin Chuang, Logan Pearce, Adrianus Boon, Yue-Wern Huang, Dong Hyun Kim, Risheng Wang, Chenglin Wu

Biological Sciences Faculty Research & Creative Works

Low-cost biosensors that can rapidly and widely detect viruses are critical for faster diagnosis and treatment decision-making, especially for infections. The commonly used field-effect transistor is sensitive to the biomarker's detection but struggles with precise detection, particularly of nontargets such as ions and proteins. To overcome this limitation, we developed a field-effect transistor biosensor design based on MXene-graphene materials to increase the accuracy and sensitivity of virus detection. Based on the hybridization process between two complementary DNA strands, single-stranded nucleic acids were immobilized on the sensing surface via 3-aminopropyltriethoxysilane and glutaraldehyde to capture the nucleic acids of the target virus. …

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Boosting The Microbial Electrosynthesis Of Formate By Shewanella Oneidensis Mr-1 With An Ionic Liquid Cosolvent, Ashwini Dantanarayana, Wassim El Housseini, Kevin Beaver, Monica Brachi, Timothy P. Mcfadden, Shelley D. Minteer Jan 2024

Boosting The Microbial Electrosynthesis Of Formate By Shewanella Oneidensis Mr-1 With An Ionic Liquid Cosolvent, Ashwini Dantanarayana, Wassim El Housseini, Kevin Beaver, Monica Brachi, Timothy P. Mcfadden, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Microbial electrosynthesis (MES) is a rapidly growing technology at the forefront of sustainable chemistry, leveraging the ability of microorganisms to catalyze electrochemical reactions to synthesize valuable compounds from renewable energy sources. The reduction of CO2 is a major target application for MES, but research in this area has been stifled, especially with the use of direct electron transfer (DET)-based microbial systems. The major fundamental hurdle that needs to be overcome is the low efficiency of CO2 reduction largely attributed to minimal microbial access to CO2 owing to its low solubility in the electrolyte. With their tunable physical …

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Aggregation And Oligomerization Characterization Of Ss-Lactoglobulin Protein Using A Solid-State Nanopore Sensor, Mitu C. Acharjee, Brad Ledden, Brian Thomas, Xianglan He, Troy Messina, Jason Giurleo, David Talaga, Jiali Li Jan 2024

Aggregation And Oligomerization Characterization Of Ss-Lactoglobulin Protein Using A Solid-State Nanopore Sensor, Mitu C. Acharjee, Brad Ledden, Brian Thomas, Xianglan He, Troy Messina, Jason Giurleo, David Talaga, Jiali Li

Physics Faculty Publications and Presentations

Protein aggregation is linked to many chronic and devastating neurodegenerative human diseases and is strongly associated with aging. This work demonstrates that protein aggregation and oligomerization can be evaluated by a solid-state nanopore method at the single molecule level. A silicon nitride nanopore sensor was used to characterize both the amyloidogenic and native-state oligomerization of a model protein ß-lactoglobulin variant A (βLGa). The findings from the nanopore measurements are validated against atomic force microscopy (AFM) and dynamic light scattering (DLS) data, comparing βLGa aggregation from the same samples at various stages. By calibrating with linear and circular dsDNA, this study …

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Weak Effects Of Prebiotically Plausible Peptides On Self-Triphosphorylation Ribozyme Function, Joshua T. Arriola, Shayan Poordian, Estefanía Martínez Valdivia, Tommy Le, Luke J. Leman, Joan G. Schellinger, Ulrich F. Müller Jan 2024

Weak Effects Of Prebiotically Plausible Peptides On Self-Triphosphorylation Ribozyme Function, Joshua T. Arriola, Shayan Poordian, Estefanía Martínez Valdivia, Tommy Le, Luke J. Leman, Joan G. Schellinger, Ulrich F. Müller

Chemistry and Biochemistry: Faculty Scholarship

Catalytic RNAs (ribozymes) were central to early stages of life on earth. The first ribozymes probably emerged in the presence of prebiotically generated peptides because amino acids can be generated under abiotic conditions, and amino acids can oligomerize into peptides under prebiotically plausible conditions. Here we tested whether the presence of prebiotically plausible peptides could have aided the emergence of ribozymes, by an in vitro selection of self-triphosphorylation ribozymes from random sequence in the presence of ten different octapeptides. These peptides were composed of ten different, prebiotically plausible amino acids, each as mixture of D- and L-stereoisomers. After five rounds …

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Problems In Chemical Graph Theory Related To The Merrifield-Simmons And Hosoya Topological Indices, William B. O'Reilly Jan 2024

Problems In Chemical Graph Theory Related To The Merrifield-Simmons And Hosoya Topological Indices, William B. O'Reilly

College of Graduate Studies: Theses & Dissertations

In some sense, chemical graph theory applies graph theory to various physical sciences. This interdisciplinary field has significant applications to structure property relationships, as well as mathematical modeling. In particular, we focus on two important indices widely used in chemical graph theory, the Merrifield-Simmons index and Hosoya index. The Merrifield-Simmons index and the Hosoya index are two well-known topological indices used in mathematical chemistry for characterizing specific properties of chemical compounds. Substantial research has been done on the two indices in terms of enumerative problems and extremal questions. In this thesis, we survey known extremal results and consider the generalized …

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Editorial: The Marine Iodine Cycle, Past, Present, And Future, Rosie Chance, Gregory A. Cutter, Dalton S. Hardisty, Anoop S. Mahajan Jan 2024

Editorial: The Marine Iodine Cycle, Past, Present, And Future, Rosie Chance, Gregory A. Cutter, Dalton S. Hardisty, Anoop S. Mahajan

OES Faculty Publications

In this Research Topic, we bring together ten articles from the diverse research communities interested in the marine iodine cycle, including paleoceanographers, atmospheric chemists, and biogeochemists. The physical chemistry underpinning iodine’s chemical speciation and transformations in the ocean is reviewed by Luther; this paper provides a theoretical basis for the field observations presented in this Research Topic.

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Marine Emissions Of Methanethiol Increase Aerosol Cooling In The Southern Ocean, Charel Wohl, Julián Villamayor, Martí Galí, Anoop S. Mahajan, Rafael P. Fernández, Carlos A. Cuevas, Adriana Bossolasco, Qinyi Li, Anthony J. Kettle, Tara Williams, Roland Sarda-Esteve, Valérie Gros, Rafel Simó, Alfonso Saiz-Lopez Jan 2024

Marine Emissions Of Methanethiol Increase Aerosol Cooling In The Southern Ocean, Charel Wohl, Julián Villamayor, Martí Galí, Anoop S. Mahajan, Rafael P. Fernández, Carlos A. Cuevas, Adriana Bossolasco, Qinyi Li, Anthony J. Kettle, Tara Williams, Roland Sarda-Esteve, Valérie Gros, Rafel Simó, Alfonso Saiz-Lopez

OES Faculty Publications

Ocean-emitted dimethyl sulfide (DMS) is a major source of climate-cooling aerosols. However, most of the marine biogenic sulfur cycling is not routed to DMS but to methanethiol (MeSH), another volatile whose reactivity has hitherto hampered measurements. Therefore, the global emissions and climate impact of MeSH remain unexplored. We compiled a database of seawater MeSH concentrations, identified their statistical predictors, and produced monthly fields of global marine MeSH emissions adding to DMS emissions. Implemented into a global chemistry-climate model, MeSH emissions increase the sulfate aerosol burden by 30 to 70% over the Southern Ocean and enhance the aerosol cooling effect while …

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Reiq-Mediated Alarmone Signalling Regulates Growth, Stress-Induced Biofilm Formation And Spore Accumulation In Clostridioides Difficile, Areej Malik, Adenrele Oludiran, Asia Poudel, Orlando Berumen Alvarez, Charles Woodward, Erin B. Purcell Jan 2024

Reiq-Mediated Alarmone Signalling Regulates Growth, Stress-Induced Biofilm Formation And Spore Accumulation In Clostridioides Difficile, Areej Malik, Adenrele Oludiran, Asia Poudel, Orlando Berumen Alvarez, Charles Woodward, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

The bacterial stringent response (SR) is a conserved transcriptional reprogramming pathway mediated by the nucleotide signalling alarmones, (pp)pGpp. The SR has been implicated in antibiotic survival in Clostridioides difficile, a biofilm- and spore-forming pathogen that causes resilient, highly recurrent C. difficile infections. The role of the SR in other processes and the effectors by which it regulates C. difficile physiology are unknown. C. difficile RelQ is a clostridial alarmone synthetase. Deletion of relQ dysregulates C. difficile growth in unstressed conditions, affects susceptibility to antibiotic and oxidative stressors and drastically reduces biofilm formation. While wild-type C. difficile displays increased biofilm …

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Multiple Variables Influence The Finely Calibrated Antioxidant Defenses Of Clostridioides Difficile, Erin B. Purcell Jan 2024

Multiple Variables Influence The Finely Calibrated Antioxidant Defenses Of Clostridioides Difficile, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

The obligate anaerobe Clostridioides difficile encodes multiple reductases to detoxify molecular oxygen and reactive oxygen species. Caulat and colleagues have characterized the activity and regulation of four such reductases (L. C. Caulat, A. Lotoux, M. C. Martins, N. Kint, et al., mBio 15:e01591-24, 2024, https://doi.org/10.1128/mbio.01591-24). Each proved critical for clostridial survival in a different range of oxygen concentrations; together, they ameliorate a broad range of oxidative stress levels. Moreover, two previously uncharacterized regulators were found to control reductase gene expression in response to oxidative stress. The genetic repressor Rex and the reductase FdpF are both sensitive to the NAP …

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Investigating The Ultrafast Dissociation Dynamics Of Energetic Materials Using Femtosecond Time-Resolved Mass Spectrometry, Jacob M. Shusterman Jan 2024

Investigating The Ultrafast Dissociation Dynamics Of Energetic Materials Using Femtosecond Time-Resolved Mass Spectrometry, Jacob M. Shusterman

Theses and Dissertations

Shock initiation of energetic materials produces cations and anions that can contribute to initial endothermic chemical reactions which lead to detonation. Hence, knowledge of the initial dissociation pathways of ionized energetic molecules is important for advancing the understanding of initiation mechanisms and meeting longstanding goals of the Department of Defense. Despite their potential importance, these transient charged species are difficult to detect in detonation experiments and are often ignored in molecular dynamics modeling of shocked energetic materials. However, the technique of pump-probe femtosecond time-resolved mass spectrometry (FTRMS) paired with complementary theoretical calculations can be used to elucidate initial unimolecular dissociation …

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Elucidation Of The Optical Properties Of Si And Si-Ge Alloy Nanostructures With Visible To Near-Ir Photoluminescence, Griffin Spence Jan 2024

Elucidation Of The Optical Properties Of Si And Si-Ge Alloy Nanostructures With Visible To Near-Ir Photoluminescence, Griffin Spence

Theses and Dissertations

Silicon and silicon-germanium alloy nanostructures have garnered increasing attention in the past 25 years due to their favorable optical properties, visible to near-IR luminescence, and inherently low toxicity. While many synthetic routes have been discussed in the literature, the high-temperature, solid-state disproportionation of hydrogen silsesquioxane (HSQ) has become the most popular way to produce highly crystalline, size-tunable Si and Si-based nanostructures (NCs). It has been shown in this work that maximum annealing temperature from 450°-1100°C and the addition of GeI2or SnCl4 precursors can be used to achieve different morphologies, alloying efficiency, and sizes. Directly annealing HSQ from …

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A Breast Cancer Stem Active Cobalt(Iii)-Cyclam Complex Containing Flufenamic Acid With Immunogenic Potential, Jiaxin Fang, Owamagbe N. Orobator, Chibuzor Ngozi Olelewe, Ginevra Passeri, Kuldip Singh, Samuel G. Awuah, Kogularamanan Suntharalingam Jan 2024

A Breast Cancer Stem Active Cobalt(Iii)-Cyclam Complex Containing Flufenamic Acid With Immunogenic Potential, Jiaxin Fang, Owamagbe N. Orobator, Chibuzor Ngozi Olelewe, Ginevra Passeri, Kuldip Singh, Samuel G. Awuah, Kogularamanan Suntharalingam

Chemistry Faculty Publications

The cytotoxic and immunogenic-activating properties of a cobalt(III)-cyclam complex bearing the non-steroidal anti-inflammatory drug, flufenamic acid is reported within the context of anti-cancer stem cell (CSC) drug discovery. The cobalt(III)-cyclam complex 1 displays sub-micromolar potency towards breast CSCs grown in monolayers, 24-fold and 31-fold greater than salinomycin (an established anti-breast CSC agent) and cisplatin (an anticancer metallopharmaceutical), respectively. Strikingly, the cobalt(III)-cyclam complex 1 is 69-fold and 50-fold more potent than salinomycin and cisplatin towards three-dimensionally cultured breast CSC mammospheres. Mechanistic studies reveal that 1 induces DNA damage, inhibits cyclooxygenase-2 expression, and prompts caspase-dependent apoptosis. Breast CSCs treated with 1 exhibit …

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Impact Of Solar Radiation On Perchlorate Formation In The Atmosphere: Evidence From Ice Core Measurements, Bishnu Kunwar Jan 2024

Impact Of Solar Radiation On Perchlorate Formation In The Atmosphere: Evidence From Ice Core Measurements, Bishnu Kunwar

Electronic Theses and Dissertations

Perchlorate, which derives from both anthropogenic and natural sources in the current environment, poses a substantial health hazard to humans as it competes with iodine uptake in the thyroid gland. Consequently, there has been considerable concern about minimizing human exposure to environmental perchlorate by restricting its release from man-made sources. However, the absence of a clear understanding regarding the respective contributions of man-made and natural sources has hindered widespread regulation efforts. A 300-year (1700–2007) Summit, Greenland ice core record from a previous study showed relatively stable perchlorate concentrations in Greenland snow prior to 1980, with some elevated perchlorate levels associated …

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Probing Microscopic Properties Of Next Generation Materials Using Coherent Vibrational And Electronic Spectroscopy, S Mudiyanselage Sachithra Tikiri Kumara Wanasinghe Jan 2024

Probing Microscopic Properties Of Next Generation Materials Using Coherent Vibrational And Electronic Spectroscopy, S Mudiyanselage Sachithra Tikiri Kumara Wanasinghe

Wayne State University Dissertations

The dissertation research focused on understanding the relationship between the chemical structure of organic molecules and their photophysical properties, particularly examining coherent electronic and vibrational coupling within and between molecules, with implications for next-generation energy technologies. In Chapter 2, we employed both steady-state and transient optical and magnetic spectroscopic techniques to understand the electronic delocalization in both singlet and triplet exciton delocalization in weakly bound porphyrin dimeric molecules. Our results highlight that the delocalization of singlet exciton delocalization does not guarantee the delocalization of triplet excitons between weakly bound porphyrin macromolecules. Our studies demonstrate how one can access the electronic …

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Design, Synthesis, And Evaluation Of Class Iia Histone Deacetylase (Hdac) Inhibitors, Lauren Nicole Kotsull Jan 2024

Design, Synthesis, And Evaluation Of Class Iia Histone Deacetylase (Hdac) Inhibitors, Lauren Nicole Kotsull

Wayne State University Dissertations

Histone deacetylase (HDAC) proteins are linked to disease states, including cancer, and have become important targets for therapeutic development. Many inhibitors have been developed to target HDAC proteins, including FDA-approved inhibitors Vorinostat (SAHA), Belinostat, Romidepsin, and Panobinostat. These inhibitors non-specifically influence most of the 11 metal-dependent HDAC isoforms, which might contribute to the side effects that patients experience during treatment. The lack of selectivity also diminishes the use of HDAC inhibitors as biomedical research tools. To address these drawbacks, the development of selective inhibitors has been heavily studied. Yet, reported inhibitors are predominantly selective for class I HDAC isoforms (HDACs …

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