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Development Of Electrochemical Biosensor For Detection Of Thyroid–Stimulating Hormone, Kittirat Kitticharoenwiwat Jan 2023

Development Of Electrochemical Biosensor For Detection Of Thyroid–Stimulating Hormone, Kittirat Kitticharoenwiwat

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation focused on the development of electrochemical paper-based immunosensor for determining thyroid-stimulating hormone (TSH) using a label-free immunoassay. Thyroid-stimulating hormone is a pituitary hormone that stimulates the thyroid gland to produce thyroid hormones for the body’s metabolism. The current electrochemiluminescence method for determining TSH as a specific biomarker indicating congenital hypothyroidism (CHT) onset is unfortunately restricted to laboratory settings, thereby resulting in limited practical utilization, delayed diagnosis, and severe outcomes. Herein, we proposed a simple, rapid, portable, and sensitive electrochemical biosensor with a label-free format based on bovine serum albumin (BSA)/graphene oxide (GO) nanocomposite for TSH determination. Caboxylated GO …

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Bamboo Biochar For Bar Adsorptive Microextraction Of Parabens In Water, Maytinee Jantorn Jan 2023

Bamboo Biochar For Bar Adsorptive Microextraction Of Parabens In Water, Maytinee Jantorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, bamboo biochar bar was prepared in the form of small-sized rods using starch as a binder and applied as a sorbent in bar adsorptive microextraction (BAµE) of parabens (methyl paraben, ethyl paraben, propyl paraben and butyl paraben) in water. The mixture of bamboo biochar which has a size of 60-80 mesh, a surface area of 102.6 m²g-1 and a pore size of 0.7 nm and starch in a weight ratio of 1:13 gave the good mechanical stability and high removal efficiency of parabens. When applied the bamboo biochar bar as a sorbent, the optimum conditions for BAµE …

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Selective Photodegradation Of Food Contaminants Using Titania-Silica-Iron Oxide Nanocomposites With Molecularly Imprinted Technology, Mehak Un Nisa Jan 2023

Selective Photodegradation Of Food Contaminants Using Titania-Silica-Iron Oxide Nanocomposites With Molecularly Imprinted Technology, Mehak Un Nisa

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, magnetic imprinted photocatalysts (Fe3O4@SiO2@TiO2@MIP and Fe3O4@SiO2@MIP@TiO2) have been synthesized successfully by surface molecular imprinting technique. 5,7-dimethoxy-coumarin was used as a dummy template to give specific recognition ability to AFB1. A range of analytical techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), vibrating sample magnetometer (VSM), and Branauer-Emmett-Teller (BET) were employed to study the crystal structure, morphology, and chemical composition of the nanocomposites. The HPLC-DAD was used to quantify the photodegradation efficiency of imprinted photocatalysts under different factors such as the source of irradiation light, initial concentration of analyte, amount of photocatalyst, and …

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Polyaniline/Cellulose Nanofiber/Polyvinyl Alcohol Hydrogel-Modified Screen-Printed Graphene Electrode For Cd2+ And Ni2+ Detection, Pichapon Boonkrong Jan 2023

Polyaniline/Cellulose Nanofiber/Polyvinyl Alcohol Hydrogel-Modified Screen-Printed Graphene Electrode For Cd2+ And Ni2+ Detection, Pichapon Boonkrong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Heavy metal contamination in wastewater has been an environmental issue, so the determination of heavy metals by an accurate and simple method is important. In this work, polyaniline/cellulose nanofiber/polyvinyl alcohol hydrogel-modified screen-printed graphene electrode (PANI/CNF/PVA hydrogel-modified SPGE) was fabricated by combining the advantages of graphene and conductive hydrogel to increase the conductivity and preconcentrate the metal ions to fabricate the modified electrode for the simultaneous detection of Cd2+ and Ni2+. First, PANI/CNF nanocomposite was synthesized by in situ chemical polymerization, and CNF was shown to prevented PANI aggregation and provided sufficient porous structure on the modified electrode. The PANI/CNF nanocomposite …

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Synthesis And Evaluation Of Sorbicillinoids, Noah Devolve Jan 2023

Synthesis And Evaluation Of Sorbicillinoids, Noah Devolve

Honors Program Theses

Sorbicillinoids are a rich family of natural products that have intrigued and inspired scientists since their initial discovery in 1948. A recent report by Zhang et al. detailed the discovery of several new monomeric sorbicillinoids that are particularly interesting as they show nitric oxide (NO) inhibition in RAW264.7 monocyte cell assays and thus possess potential as anti-inflammatory agents. Based on this information, obtaining more of these novel compounds and establishing a preliminary structure activity relationship (SAR) could be achieved by modulating the substitution pattern on the molecules’ benzene ring and varying the alkyl chain length. To this end, a flexible …

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Feminist Pedagogy In Stem: The Intersection Of Stem Pedagogy And Feminist Theory, Lesley Ann Giddings, Candice Price Jan 2023

Feminist Pedagogy In Stem: The Intersection Of Stem Pedagogy And Feminist Theory, Lesley Ann Giddings, Candice Price

Chemistry: Faculty Publications

Science, technology, engineering, and mathematics (STEM) education aims to cultivate the capacity for innovation and real-world problem-solving (Marrero et al., 2014). However, STEM pedagogy has not historically aligned with this goal, often failing to teach students the necessary skills and mindset for creative problem-solving (Stehle & Peters-Burton, 2019). Traditional STEM pedagogical methods, such as rote and lecture-based learning, are based on the teacher being the dominant source of knowledge and students being the passive receivers (Achuonye, 2015; Khalaf & Mohammed Zin, 2018). These methods lack student support, collaboration, active learning, and real-world contexts (Gasiewski et al., 2012). Furthermore, the exclusion …

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Creating Meaningful Connections With The Electr Eating Meaningful Connections With The Electron Transport Chain Beyond A Virtual Classroom, Lesley Ann Giddings Jan 2023

Creating Meaningful Connections With The Electr Eating Meaningful Connections With The Electron Transport Chain Beyond A Virtual Classroom, Lesley Ann Giddings

Chemistry: Faculty Publications

At the center of feminist pedagogy is community. Creating community within the classroom and between the class and local communities increases student engagement and access to knowledge. Communities can be a source of solidarity and further decenter authority in the classroom, empowering students, teachers, and the surrounding community to be co-learners. Amid the COVID-19 pandemic, remote teaching posed challenges to student engagement. Here, I describe an assignment used to build an inclusive community of co-learners within a virtual biochemistry class and our local communities. Oxidative phosphorylation is a cellular process used to create energy that depends on the electron transport …

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Lead Induced Differences In Bone Properties In Osteocalcin +/+ And −/− Female Mice, G. Yildirim, W. C. Budell, O. Berezovska, S. Yagerman, S. S. Maliath, P. Mastrokostas, S. Tommasini, T. L. Dowd Jan 2023

Lead Induced Differences In Bone Properties In Osteocalcin +/+ And −/− Female Mice, G. Yildirim, W. C. Budell, O. Berezovska, S. Yagerman, S. S. Maliath, P. Mastrokostas, S. Tommasini, T. L. Dowd

Publications and Research

Lead (Pb) toxicity is a major health problem and bone is the major reservoir. Lead is detrimental to bone, affects bone remodelingand is associated with elderly fractures. Osteocalcin (OC) affects bone remodeling, improves fracture resistance and decreases with age and in some diseases. The effect of lead in osteocalcin depleted bone is unknown and of interest. We compared bone mineral properties of control and Pb exposed (from 2 to 6 months) femora from female adult C57BL6 OC+/+ and OC−/− mice using Fourier Transform Infrared Imaging (FTIRI), Micro-computed tomography (uCT), bone biomechanical measurements and serum turnover markers (P1NP, CTX). Lead significantly …

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Room-Temperature Crystallography Reveals Altered Binding Of Small-Molecule Fragments To Ptp1b, Tamar Skaist Mehlman, Justin T. Biel, Syeda Maryam Azeem, Elliot R. Nelson, Sakib Hossain, Louise Dunnett, Neil G. Paterson, Alice Douangamath, Romain Talon, Danny Axford, Helen Orins, Frank Von Delft, Daniel A. Keedy Jan 2023

Room-Temperature Crystallography Reveals Altered Binding Of Small-Molecule Fragments To Ptp1b, Tamar Skaist Mehlman, Justin T. Biel, Syeda Maryam Azeem, Elliot R. Nelson, Sakib Hossain, Louise Dunnett, Neil G. Paterson, Alice Douangamath, Romain Talon, Danny Axford, Helen Orins, Frank Von Delft, Daniel A. Keedy

Advanced Science Research Center

Much of our current understanding of how small-molecule ligands interact with proteins stems from X-ray crystal structures determined at cryogenic (cryo) temperature. For proteins alone, room-temperature (RT) crystallography can reveal previously hidden, biologically relevant alternate conformations. However, less is understood about how RT crystallography may impact the conformational landscapes of protein-ligand complexes. Previously, we showed that small-molecule fragments cluster in putative allosteric sites using a cryo crystallographic screen of the therapeutic target PTP1B (Keedy et al., 2018). Here, we have performed two RT crystallographic screens of PTP1B using many of the same fragments, representing the largest RT crystallographic screens of …

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Investigations Into Indole Formation: Base-Mediated Formation Of N-Hydroxy- And N-Alkoxyindoles, Ancillary Ligand Development For Watanabe-Cenini-Söderberg Cyclization, And Total Synthesis Of Racemosin B, Blaine Thomas Mcclay Jan 2023

Investigations Into Indole Formation: Base-Mediated Formation Of N-Hydroxy- And N-Alkoxyindoles, Ancillary Ligand Development For Watanabe-Cenini-Söderberg Cyclization, And Total Synthesis Of Racemosin B, Blaine Thomas Mcclay

Graduate Theses, Dissertations, and Problem Reports (ETD)

A novel, base-mediated cyclization was developed to form N-hydroxy- and N-alkoxyindoles from 2-(2-nitrophenyl)butenoates. Potassium tert-butoxide or sodium tert-pentoxide, with or without the in-situ addition of an electrophile, formed a multitude of N-hydroxy- and N-alkoxyindoles. The formation of these butanoate precursors was improved via a Barluenga coupling reaction. Novel 4,5,6,7-tetramethoxy-1,10-phenanthroline was utilized as an ancillary ligand within the Watanabe-Cenini-Söderberg reductive cyclization reaction conditions. These new reaction conditions produced high yields for sterically hindered 2-nitrostyrenes and the first synthesis of dilemmaone A using this reductive cyclization. Racemosin B was synthesized in a three-step process utilizing a …

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Evaluating The Effect Of Resveratrol On Sirt1 With Different Peptide Substrates, Yujin Hur Jan 2023

Evaluating The Effect Of Resveratrol On Sirt1 With Different Peptide Substrates, Yujin Hur

Master's Theses

SIRT1 is an NAD+-dependent lysine deacetylase that is involved in many important cellular pathways. The protein has an extended N-terminal domain that seems to play a role in regulating its activity. Sirtuin Activating Compounds (STACs) are allosteric activators, such as resveratrol, that regulate the activity of SIRT1. STACs bind to the N-terminal STAC Binding Domain (SBD) in SIRT1. Past literature has found that SIRT1 activity can be increased, decreased, or remain unchanged by resveratrol depending on the identity of the peptide substrate. The goal of this study is to clarify the mechanism for substrate-specific allosteric regulation by resveratrol. The interactions …

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Characterization And Evaluation Of Catalytic Activity Of Small Molecule Copper Complexes For Metallopolymer Design, Brenda Lu Jan 2023

Characterization And Evaluation Of Catalytic Activity Of Small Molecule Copper Complexes For Metallopolymer Design, Brenda Lu

Master's Theses

Catalysis is one of the driving forces in designing greener chemical processes for essential real-world applications. Enzymes, Nature’s catalysts, are known for their high selectivity, use of readily available metals and reagents, and ability to work under physiological conditions; three important qualities that synthetic chemists would like to mimic in their small molecule metal catalysts. Though most small molecule metal catalysts fall short of enzyme-like activity, we hypothesize that using a polymer scaffold as a secondary coordination sphere mimic around the metal complex will affect the microenvironment (steric and electronic) and enable enzyme-like activity. Previously, we synthesized ligand precursors and …

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On Chip Microfluidic Separation Of Cyclotides, Reza Didarian, Aliakbar Ebrahimi, Hamed Ghorbanpoor, Hesam Bagheroghli, Fatma Doğan Güzel, Mohsen Farhadpour, Nasrin Lotfibakhshayesh, Hossein Hashempour, Hüseyi̇n Avci Jan 2023

On Chip Microfluidic Separation Of Cyclotides, Reza Didarian, Aliakbar Ebrahimi, Hamed Ghorbanpoor, Hesam Bagheroghli, Fatma Doğan Güzel, Mohsen Farhadpour, Nasrin Lotfibakhshayesh, Hossein Hashempour, Hüseyi̇n Avci

Turkish Journal of Chemistry

Cyclotides as a cyclic peptide produced by different groups of plants have been a very attractive field of research due to their exceptional properties in biological activities and drug design applications. The importance of cyclotides as new biological activities from nature caused to attract researchers to develop new separation systems. Recent growth and development on chip-based technology for separation and bioassay especially for anticancer having sparklingly advantages comparison with common traditional methods. In this study, the microfluidic separation of Vigno 1-5 cyclotides extracted from Viola ignobilis by using polar and nonpolar forces as a liquid-liquid interaction was investigated through modified …

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Kinetic Mechanism Of Dimethylsulfone Monooxygenase And Its Immobilized Magnetic Nanoparticles, Montisa Mangkalee Jan 2023

Kinetic Mechanism Of Dimethylsulfone Monooxygenase And Its Immobilized Magnetic Nanoparticles, Montisa Mangkalee

Chulalongkorn University Theses and Dissertations (Chula ETD)

The dimethyl sulfone monooxygenase system is a two-component flavoprotein catalyzing the monooxygenation of dimethyl sulfone (DMSO2) by oxidative cleavage producing methanesulfinate and formaldehyde. The reductase component (DMSR) is a flavoprotein with FMN as a cofactor catalyzing flavin reduction using NADH. The oxygenase (DMSMO) uses reduced flavin from the reductase and oxygen for substrate monooxygenation. DMSMO can bind to FMN and FMNH– with a Kd of 17.4 ± 0.9 µM and 4.08 ± 0.8 mM, respectively. The binding of FMN to DMSMO is required prior to binding DMSO2. Substituting reduced DMSR with FMNH– demonstrated the same oxidation kinetics, indicating that FMNH- …

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Development Of Novel Cellular Assay Model And Therapeutic Deep Eutectic Solvents To Optimize The Activity Of Anticancer Agents, Nizam Uddin Jan 2023

Development Of Novel Cellular Assay Model And Therapeutic Deep Eutectic Solvents To Optimize The Activity Of Anticancer Agents, Nizam Uddin

Electronic Theses and Dissertations

Multidrug resistance (MDR) is the major burden behind chemotherapeutic treatment failure. It is the principal mechanism by which cancer cells evade chemotherapeutic treatment. As a result, aggressive cancer cells survive and continue uncontrolled cell division. Multidrug resistance affects survival rate of almost all types of cancer patients and death toll rises at an alarming rate. There are seven different mechanisms for evolving MDR. The most common mechanism in efflux activity of overexpressed ABC transporters. MRP1 is a prominent ABC transporter that pumps out a wide variety of anticancer drugs from the cells and thereby reduces intracellular drug concentrations and develops …

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Design, Synthesis, And Biological Evaluation Of Novel Steroidal Analogs: Potential Anticancer Agents, Trevor Ostlund Jan 2023

Design, Synthesis, And Biological Evaluation Of Novel Steroidal Analogs: Potential Anticancer Agents, Trevor Ostlund

Electronic Theses and Dissertations

Cancer is a malicious disease with low survivability rates primarily due to lack of reliable treatment options. Treatments are often non-specific for patients, and cancer resistance to treatment is becoming more prevalent as fast as new therapies are created. Previous studies in our laboratory have focused on the Epidermal Growth Factor Receptor (EGFR) and its downstream kinase family members as a key target for cancer. This cascade controls cell proliferation, anti-apoptotic effects, cell regulation, and other survival factors. Additionally, ABC transporters, responsible for efflux of chemotherapeutic material from cells, are key targets to combat drug resistance. We first evaluated a …

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Comprehensive Analysis And Forensic Investigation Of Cyanide, Thiocyanate, And 2-Amino-2-Thiazoline-4-Carboxylic Acid In-Ante- And Postmortem Blood Utilizing Advanced Analytical Techniques, Abdullah Hamad Alluhayb Jan 2023

Comprehensive Analysis And Forensic Investigation Of Cyanide, Thiocyanate, And 2-Amino-2-Thiazoline-4-Carboxylic Acid In-Ante- And Postmortem Blood Utilizing Advanced Analytical Techniques, Abdullah Hamad Alluhayb

Electronic Theses and Dissertations

Cyanide (CN), present as cyanide anion (CN-) or hydrogen cyanide (HCN), is a deadly poison. The main mechanism of CN toxicity is blocking terminal electron transfer, leading to cellular hypoxia, cytotoxic anoxia, and potential death. Determining blood CN concen-trations along with its major metabolite, thiocyanate (SCN-), is crucial. A sensitive method for concurrent detection of CN and SCN- from human ante- and post-mortem blood via liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis was devel-oped. The method involved active microdiffusion with chemical modification using naph-thalene-2,3-dicarboxaldehyde (NDA) and taurine, while monobromobimane (MBB) mod-ification was used for SCN-. The method showed good sensitivity for …

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Computational Investigation Of The Ionization Potential Of Lead Sulfide Quantum Dots, Jessica Beyer Jan 2023

Computational Investigation Of The Ionization Potential Of Lead Sulfide Quantum Dots, Jessica Beyer

Scripps Senior Theses

The purpose of this work was to determine the impact of quantum dot size on ionization potential and to determine how the presence of carbonyl-based ligands affect the ionization potential of lead sulfide quantum dot systems. Ionization potential (IP) is defined as the energy required to remove an electron from an atom, molecule, or material. IP helps scientists determine how reactive the material of interest is, which is crucial information when manufacturing nanomaterials. Accurate quantum chemical calculations of ionization potential are challenging due to the computational cost associated with the numerical solution of the Dyson equation. In this work, the …

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How Akron Affects The Water Quality Of The Cuyahoga River, Allyson Darst Jan 2023

How Akron Affects The Water Quality Of The Cuyahoga River, Allyson Darst

Williams Honors College, Honors Research Projects

The purpose of this study was to analyze whether the city of Akron had negative effects on the Cuyahoga river, and determine if the Cuyahoga River was naturally able to remediate these effects downstream. The pollutants measured in this study include hardness, bromine, residual chlorine, iron, copper, lead, nitrate, nitrite, ammonium chloride, total chlorine, fluoride, carbonate, pH, total alkalinity and cyanuric acid. This study was done using water testing strips (JNW Direct) to test the water at four different locations along the Cuyahoga River downstream (North) of Akron. This study found that the city of Akron does have a negative …

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An Explainable Deep Learning Model For Prediction Of Severity Of Alzheimer's Disease, Godwin Ekuma, Daniel B. Hier, Tayo Obafemi-Ajayi Jan 2023

An Explainable Deep Learning Model For Prediction Of Severity Of Alzheimer's Disease, Godwin Ekuma, Daniel B. Hier, Tayo Obafemi-Ajayi

Chemistry Faculty Research & Creative Works

Deep Convolutional Neural Networks (CNNs) have become the go-To method for medical imaging classification on various imaging modalities for binary and multiclass problems. Deep CNNs extract spatial features from image data hierarchically, with deeper layers learning more relevant features for the classification application. Despite the high predictive accuracy, usability lags in practical applications due to the black-box model perception. Model explainability and interpretability are essential for successfully integrating artificial intelligence into healthcare practice. This work addresses the challenge of an explainable deep learning model for the prediction of the severity of Alzheimer's disease (AD). AD diagnosis and prognosis heavily rely …

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Natural Product Co-Metabolism And The Microbiota–Gut–Brain Axis In Age-Related Diseases, Mark Obrenovich, Sandeep Kumar Singh, Yi Li, George Perry, Bushra Siddiqui, Waqas Haq, V. Prakash Reddy Jan 2023

Natural Product Co-Metabolism And The Microbiota–Gut–Brain Axis In Age-Related Diseases, Mark Obrenovich, Sandeep Kumar Singh, Yi Li, George Perry, Bushra Siddiqui, Waqas Haq, V. Prakash Reddy

Chemistry Faculty Research & Creative Works

Complementary alternative medicine approaches are growing treatments of diseases to standard medicine practice. Many of these concepts are being adopted into standard practice and orthomolecular medicine. Age-related diseases, in particular neurodegenerative disorders, are particularly difficult to treat and a cure is likely a distant expectation for many of them. Shifting attention from pharmaceuticals to phytoceuticals and "bugs as drugs" represents a paradigm shift and novel approaches to intervention and management of age-related diseases and downstream effects of aging. Although they have their own unique pathologies, a growing body of evidence suggests Alzheimer's disease (AD) and vascular dementia (VaD) share common …

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The Affect Of Dha Concentration On Lipid Membrane Fluidity, Elise Rezabeck Jan 2023

The Affect Of Dha Concentration On Lipid Membrane Fluidity, Elise Rezabeck

Williams Honors College, Honors Research Projects

My proposed project will be creating large unilaminar vesicles with varying concentrations of DHA in the vesicles. The diffusion in and out of these vesicles will be tracked by using singular lipid molecules. These singular lipid molecules will be tagged with fluorescence and viewed using an internal reflection fluorescence microscope. The data collected over the course of this project will then be analyzed using Matlab. The result of the project will be to find the specific lipid diffusion constant of these unilaminar vesicles. The relationship between the concentration of DHA and lipid diffusion and membrane fluidity will be found as …

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Method Development For The Quantification Of Heavy Metals In Biological Matrices And Its Application To Clinical And Environmental Samples, Michelle Catherine Gende Jan 2023

Method Development For The Quantification Of Heavy Metals In Biological Matrices And Its Application To Clinical And Environmental Samples, Michelle Catherine Gende

Dissertations

A three-fold approach was taken to develop a method for the detection of heavy metals in different matrices and had to be performed sequentially. The first was to develop a method capable of quantifying lead in complex matrices by graphite furnace atomic absorption (GFAA). The developed method needed to meet specific analytical requirements, namely, to be robust, sensitive, and accurate. Initially, four different sample preparation methods were explored for the quantification of lead using Escherichia coli (E. coli) as a sample matrix. The sample preparation procedures attempted were acidic dilution, matrix modification, conventional heating digestion, and microwave assisted acid digestion …

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Wetting Transition Of Texturized Surfaces, Jenna Stephens Jan 2023

Wetting Transition Of Texturized Surfaces, Jenna Stephens

Williams Honors College, Honors Research Projects

Building on previous research, this project aims to continue the investigation of the wettability of various liquids on a uniform, texturized surface. Different surface energies can impact the wettability of a surface. The surface can be hydrophilic, hydrophobic, or in between. The goal of this project is to research how features of texturized surfaces affect the wetting transition of water, oil, and a mixture of both. Additionally, this project aims to improve the quality of the 3D printed surfaces. The surfaces that will be studied are constructed using UV cured resin 3D printing and are made up of an array …

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Expanding Our Grasp Of Two-Component Signaling In Clostridioides Difficile, Orlando Berumen Alvarez, Erin B. Purcell Jan 2023

Expanding Our Grasp Of Two-Component Signaling In Clostridioides Difficile, Orlando Berumen Alvarez, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

The intestinal pathogen Clostridioides difficile encodes roughly 50 TCS, but very few have been characterized in terms of their activating signals or their regulatory roles. A. G. Pannullo, B. R. Zbylicki, and C. D. Ellermeier (J Bacteriol 205:e00164-23, 2023, https://doi.org/10.1128/jb.00164-23) have identified both for the novel C. difficile TCD DraRS. DraRS responds to antibiotics that target lipid-II molecules in the bacterial cell envelope, and regulates the production of a novel glycolipid necessary for bacitracin and daptomycin resistance in C. difficile.

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Uhplc/Ft-Ms Non-Targeted Screening Approach For Biomass Burning Organic Aerosol And Liquid Smoke As Biomass Burning Organic Aerosol Surrogate, D.M.R. Thusitha Dinusha Kumarihami Divisekara Jan 2023

Uhplc/Ft-Ms Non-Targeted Screening Approach For Biomass Burning Organic Aerosol And Liquid Smoke As Biomass Burning Organic Aerosol Surrogate, D.M.R. Thusitha Dinusha Kumarihami Divisekara

Dissertations, Master's Theses and Master's Reports

Biomass combustion contributes a large amount of aerosol particles to the atmosphere impacting the climate system and human health. Identifying the molecular composition of biomass burning organic aerosol (BBOA) is challenging because of its complex nature. Liquid chromatography mass spectrometric non-targeted screening (NTS) methods provide a comprehensive analysis. However, the instrumentation and data analysis are challenging due to the extreme complexity of environmental samples. In the first part of this study, we implemented a new LC/FT-MS data processing approach by combining existing open-source data processing tools, MZmine2.53 and MFAssignR. The method's validity was checked using the standard polyacrylic acid (PAA) …

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A Monoadduct Generating Ru(Ii) Complex Induces Ribosome Biogenesis Stress And Is A Molecular Mimic Of Phenanthriplatin, Richard Joseph Mitchell, Sarah M. Kriger, Alexander D. Fenton, Dmytro Havrylyuk, Ankit Pandeya, Yang Sun, Tami Smith, Jason E. Derouchey, David K. Heidary, Edith C. Glazer Jan 2023

A Monoadduct Generating Ru(Ii) Complex Induces Ribosome Biogenesis Stress And Is A Molecular Mimic Of Phenanthriplatin, Richard Joseph Mitchell, Sarah M. Kriger, Alexander D. Fenton, Dmytro Havrylyuk, Ankit Pandeya, Yang Sun, Tami Smith, Jason E. Derouchey, David K. Heidary, Edith C. Glazer

Markey Cancer Center Faculty Publications

Ruthenium complexes are often investigated as potential replacements for platinum-based chemotherapeutics in hopes of identifying systems with improved tolerability in vivo and reduced susceptibility to cellular resistance mechanisms. Inspired by phenanthriplatin, a non-traditional platinum agent that contains only one labile ligand, monofunctional ruthenium polypyridyl agents have been developed, but until now, few demonstrated promising anticancer activity. Here we introduce a potent new scaffold, based on [Ru(tpy)(dip)Cl]Cl (tpy = 2,20:60,200-terpyridine and dip = 4,7-diphenyl-1,10-phenanthroline) in pursuit of effective Ru(II )-based monofunctional agents. Notably, the extension of the terpyridine at the 40 position with an aromatic ring resulted in a molecule that …

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Computational Investigation Of A Series Of Small Molecules As Potential Compounds For Lysyl Hydroxylase-2 (Lh2) Inhibition, Yazdan Maghsoud, Erik Antonio Vázquez-Montelongo, Xudong Yang, Chengwen Liu, Zhifeng Jing, Juhoon Lee, Matthew Harger, Ally K. Smith, Miguel Espinoza, Hou-Fu Guo, Jonathan M. Kurie, Kevin N. Dalby, Pengyu Ren, G. Andrés Cisneros Jan 2023

Computational Investigation Of A Series Of Small Molecules As Potential Compounds For Lysyl Hydroxylase-2 (Lh2) Inhibition, Yazdan Maghsoud, Erik Antonio Vázquez-Montelongo, Xudong Yang, Chengwen Liu, Zhifeng Jing, Juhoon Lee, Matthew Harger, Ally K. Smith, Miguel Espinoza, Hou-Fu Guo, Jonathan M. Kurie, Kevin N. Dalby, Pengyu Ren, G. Andrés Cisneros

Markey Cancer Center Faculty Publications

The catalytic function of lysyl hydroxylase-2 (LH2), a member of the Fe(II)/αKG-dependent oxygenase superfamily, is to catalyze the hydroxylation of lysine to hydroxylysine in collagen, resulting in stable hydroxylysine aldehyde-derived collagen cross- links (HLCCs). Reports show that high amounts of LH2 lead to the accumulation of HLCCs, causing fibrosis and specific types of cancer metastasis. Some members of the Fe(II)/αKG-dependent family have also been reported to have intramolecular O2 tunnels, which aid in transporting one of the required cosubstrates into the active site. While LH2 can be a promising target to combat these diseases, efficacious inhibitors are still lacking. We …

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Polycomb Deficiency Drives A Foxp2-High Aggressive State Targetable By Epigenetic Inhibitors, Fan Chen, Aria Byrd, Jinpeng Liu, Robert M. Flight, Tanner Ducote, Kassandra J. Naughton, Xiulong Song, Abigail R Edgin, Alexsandr Lukyanchuk, Danielle T. Dixon, Christian M. Gosser, Dave-Preston Esoe, Rani Jayswal, Stuart H. Orkin, Hunter N. B. Moseley, Chi Wang, Christine Fillmore Brainson Jan 2023

Polycomb Deficiency Drives A Foxp2-High Aggressive State Targetable By Epigenetic Inhibitors, Fan Chen, Aria Byrd, Jinpeng Liu, Robert M. Flight, Tanner Ducote, Kassandra J. Naughton, Xiulong Song, Abigail R Edgin, Alexsandr Lukyanchuk, Danielle T. Dixon, Christian M. Gosser, Dave-Preston Esoe, Rani Jayswal, Stuart H. Orkin, Hunter N. B. Moseley, Chi Wang, Christine Fillmore Brainson

Markey Cancer Center Faculty Publications

Inhibitors of the Polycomb Repressive Complex 2 (PRC2) histone methyltransferase EZH2 are approved for certain cancers, but realizing their wider utility relies upon understanding PRC2 biology in each cancer system. Using a genetic model to delete Ezh2 in KRAS-driven lung adenocarcinomas, we observed that Ezh2 haplo-insufficient tumors were less lethal and lower grade than Ezh2 fully-insufficient tumors, which were poorly differentiated and metastatic. Using three-dimensional cultures and in vivo experiments, we determined that EZH2-deficient tumors were vulnerable to H3K27 demethylase or BET inhibitors. PRC2 loss/inhibition led to de-repression of FOXP2, a transcription factor that promotes migration and stemness, and FOXP2 …

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Histidine Enhances The Anticancer Effect Of Gemcitabine Against Pancreatic Cancer Via Disruption Of Amino Acid Homeostasis And Oxidant—Antioxidant Balance, Narendra Kumar, Satyanarayana Rachagani, Gopalakrishnan Natarajan, Alexandra Crook, Thiyagarajan Gopal, Vinothkumar Rajamanickam, Jyoti B. Kaushal, Sirpu N. Nagabhishek, Robert Powers, Surinder K. Batra, Viswanathan Saraswathi Jan 2023

Histidine Enhances The Anticancer Effect Of Gemcitabine Against Pancreatic Cancer Via Disruption Of Amino Acid Homeostasis And Oxidant—Antioxidant Balance, Narendra Kumar, Satyanarayana Rachagani, Gopalakrishnan Natarajan, Alexandra Crook, Thiyagarajan Gopal, Vinothkumar Rajamanickam, Jyoti B. Kaushal, Sirpu N. Nagabhishek, Robert Powers, Surinder K. Batra, Viswanathan Saraswathi

Robert Powers Publications

Simple Summary: Amino acid metabolism is aberrantly altered in pancreatic cancer (PC). Evidence suggests that circulating histidine (His) levels are low in PC. However, the role of His in modulating the progression of PC remains unknown. We determined the role of His in altering the therapeutic effectiveness of gemcitabine (Gem) against PC. We provide evidence that the expression of histidine ammonia lyase (HAL), an enzyme involved in His catabolism, is greatly increased in mouse and human pancreatic tumors. We show that combining His with Gem led to enhanced cytotoxic effects against aggressive PC cell lines. Our metabolomics analysis revealed that …

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