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Articles 121 - 150 of 576
Full-Text Articles in Chemicals and Drugs
Alphafold2 Modeling And Molecular Dynamics Simulations Of The Conformational Ensembles For The Sars-Cov-2 Spike Omicron Jn.1, Kp.2 And Kp.3 Variants: Mutational Profiling Of Binding Energetics Reveals Epistatic Drivers Of The Ace2 Affinity And Escape Hotspots Of Antibody Resistance, Nishank Raisinghani, Mohammed Alshahrani, Grace Gupta, Gennady M. Verkhivker
Alphafold2 Modeling And Molecular Dynamics Simulations Of The Conformational Ensembles For The Sars-Cov-2 Spike Omicron Jn.1, Kp.2 And Kp.3 Variants: Mutational Profiling Of Binding Energetics Reveals Epistatic Drivers Of The Ace2 Affinity And Escape Hotspots Of Antibody Resistance, Nishank Raisinghani, Mohammed Alshahrani, Grace Gupta, Gennady M. Verkhivker
Mathematics, Physics, and Computer Science Faculty Articles and Research
AlphaFold2-based atomistic predictions of structures and conformational ensembles of the SARS-CoV-2 spike complexes with the host receptor ACE2 for the most dominant Omicron variants JN.1, KP.1, KP.2 and KP.3 to examine the mechanisms underlying the role of convergent evolution hotspots in balancing ACE2 binding and antibody evasion. Using the ensemble-based mutational scanning of the spike protein residues and computations of binding affinities, we identified binding energy hotspots and characterized the molecular basis underlying epistatic couplings between convergent mutational hotspots. The results suggested the existence of epistatic interactions between convergent mutational sites at L455, F456, Q493 positions that protect and restore …
Improving Ligand Pharmacokinetics Via Bioisosteric Substitution Of Amides With 1, 2, 3-Triazoles While Maintaining Dopamine D4 Receptor Selectivity And Potency, Mohammad Alkhatib
Improving Ligand Pharmacokinetics Via Bioisosteric Substitution Of Amides With 1, 2, 3-Triazoles While Maintaining Dopamine D4 Receptor Selectivity And Potency, Mohammad Alkhatib
Theses and Dissertations
Several neurophysiological functions, such as attention, cognition, and emotional regulation, are regulated by the binding of dopamine on G-Protein coupled receptors. D4Rs are mainly located in the prefrontal cortex and the hippocampus and are known to have a key role in decision-making, memory formation, cognition, and attention. Administration of D4Rs- selective ligands during the preclinical studies enhance the outcomes and the results in animal models suffering from neuropsychiatric disorders, including ADHD, substance use disorders (SUD), and Alzheimer's disease. Recently, we reported a group of D4R-selective ligands with different efficacies depending on their phenylpiperazine ring scaffold to illustrate D4R function during …
Incorporating Solvation Thermodynamic Mapping In Computer-Aided Drug Design, Yeonji Ji
Incorporating Solvation Thermodynamic Mapping In Computer-Aided Drug Design, Yeonji Ji
Dissertations, Theses, and Capstone Projects
Advancements in computational techniques have revolutionized structure-based drug design, substantially improving the efficiency and effectiveness of the drug discovery process by reducing time, costs, and labor requirements. These advancements include various methods, such as investigating small molecule ligands binding to proteins, exploring alternative protein conformations, and solvation mapping on the protein surfaces. Among these methods, understanding the correlation between protein-ligand binding and the role of solvation is important.
A fundamental concept in protein-ligand binding is shape and electrostatic complementarity, which is complicated by the inherent flexibility of proteins. In the absence of small molecule ligands, proteins are complementary to surface …
Occurrence, Inputs, And Ecological Significance Of Antibiotics And Pharmaceuticals In Western Nebraska Streams, Katelyn F. Glause
Occurrence, Inputs, And Ecological Significance Of Antibiotics And Pharmaceuticals In Western Nebraska Streams, Katelyn F. Glause
School of Natural Resources: Dissertations, Theses, and Student Research
Few emerging environmental contaminants are as concerning as antibiotics. Human and animal health benefits greatly from the prudent use of antibiotics, yet we give little thought to environmental release of these biologically active compounds. Environmental occurrence of these and other pharmaceutical compounds must be measured in different environmental compartments such as municipal wastewater and in the vicinity of large animal feeding operations to understand potential effects. This study reports the results of a monitoring study in western Nebraska, with a large population of livestock and smaller but more concentrated population of humans, comparing the relative environmental concentrations and loading from …
Experimental And Theoretical Investigation Of The Coordination Of 8-Hydroxquinoline Inhibitors To Biomimetic Zinc Complexes And Histone Deacetylase 8 (Hdac8), Anthony M. Baudino, Harris F. Ciaccio, Michael J. Turski, Xavier A. Akins, Phoebus Sun Cao, Elisa Morales, Roger D. Sommer, Adam R. Johnson, Donald J. Wink, Kyle A. Grice, Kari Stone
Experimental And Theoretical Investigation Of The Coordination Of 8-Hydroxquinoline Inhibitors To Biomimetic Zinc Complexes And Histone Deacetylase 8 (Hdac8), Anthony M. Baudino, Harris F. Ciaccio, Michael J. Turski, Xavier A. Akins, Phoebus Sun Cao, Elisa Morales, Roger D. Sommer, Adam R. Johnson, Donald J. Wink, Kyle A. Grice, Kari Stone
Chemistry Department Faculty Articles
Zinc is integral to diverse biological functions, acting catalytically, structurally, and supportively in essential enzyme cycles, despite its limited amounts in the body. Targeting zinc enzymes with potent drugs, such as Vorinostat, demonstrates the therapeutic efficacy of zinc-binding ligands, notably in cutaneous T-cell lymphoma treatments. Our study merges experimental and theoretical approaches to analyze the coordination of 8-hydroxylquinoline (8HQ) inhibitors with biomimetic zinc complexes and human histone deacetylase 8 (HDAC8), a monozinc hydrolase enzyme. Assessing 10 8HQ derivatives for structural and electronic characteristics against these models, we observe minimal inhibition efficacy, corroborated through protein–ligand docking analyses, highlighting the complexities of …
Innovation Path At Institute For Protein Design Of Washington University And Its Enlightenment For Construction Of New Life Sciences R&D Institutions, Runzhou Zhao, Ming Ni, Yunzhi Fa, Xiaochen Bo, Jian Jiao
Innovation Path At Institute For Protein Design Of Washington University And Its Enlightenment For Construction Of New Life Sciences R&D Institutions, Runzhou Zhao, Ming Ni, Yunzhi Fa, Xiaochen Bo, Jian Jiao
Bulletin of Chinese Academy of Sciences (Chinese Version)
The Institute for Protein Design (IPD) at the University of Washington is a pioneering local and state-supported non-profit scientific research institution. Since its establishment in 2012, IPD has seized the opportunity of AI for Science and open science, and continuously enhanced its capabilities of fundamental innovations, breakthrough technologies, and industrial impact. We summarized five factors contributing to IPD’s development, including focusing on the cutting-edge issues of basic scientific research to gain a first-mover advantage and then further expand, integrating AI-enhanced digital tools and solid experimental validations, facilitating the integrated development of innovation and industrial chains, giving full play to the …
A Model Of Oocyte Population Dynamics For Fish Oogenesis, Louis Fostier, Frédérique Clément, Romain Yvinec, Violette Thermes
A Model Of Oocyte Population Dynamics For Fish Oogenesis, Louis Fostier, Frédérique Clément, Romain Yvinec, Violette Thermes
Biology and Medicine Through Mathematics Conference
No abstract provided.
Bioactive Glass Bead Characterization: Further Applications In Passive Drug Delivery, Marie O. Sykes
Bioactive Glass Bead Characterization: Further Applications In Passive Drug Delivery, Marie O. Sykes
Physics and Astronomy Honors Papers
Bioactive glass beads were discovered for their bone repair properties in 1969. This properties, along with their bactericidalness, high ability to be engineered, bioactiveness and their versatile structures, mark them as excellent candidates for explorations in other biomedical applications in addition to bone repair. One alternative application includes passive drug delivery, especially when the biomaterial is in a porous, microsphere structure. In this work, we first explore various samples of bioactive glass compositions and structures in order to target the best bead for the application of drug delivery. The targeted beads are then thoroughly characterized using optical microscopy, Scanning Electron …
A Revised Synthesis Of The Cationic Lipids Dmri And Mlri, Benjamin A. Kostic
A Revised Synthesis Of The Cationic Lipids Dmri And Mlri, Benjamin A. Kostic
College of Arts & Sciences Senior Theses
Lipid nanoparticles (LNPs) are an increasingly utilized method of intracellular delivery for nucleic acids. The COVID-19 vaccines from Moderna and Pfizer-BioNTech have used LNP technology to combat the recent global SARS-CoV-2 pandemic, saving millions of lives.1,2 These vaccines consist of a lipid formulation that binds to the anionic phosphate groups of mRNAs and serves as an effective way to transport the nucleic acid across membranes into cells.9The mRNA encodes a viral protein. When introduced to cells, the viral protein is produced so that the immune system then can generate an appropriate antibody response.3 However, this approach …
Exploring Binding Pockets In The Conformational States Of The Sars-Cov-2 Spike Trimers For The Screening Of Allosteric Inhibitors Using Molecular Simulations And Ensemble-Based Ligand Docking, Grace Gupta, Gennady M. Verkhivker
Exploring Binding Pockets In The Conformational States Of The Sars-Cov-2 Spike Trimers For The Screening Of Allosteric Inhibitors Using Molecular Simulations And Ensemble-Based Ligand Docking, Grace Gupta, Gennady M. Verkhivker
Mathematics, Physics, and Computer Science Faculty Articles and Research
Understanding mechanisms of allosteric regulation remains elusive for the SARS-CoV-2 spike protein, despite the increasing interest and effort in discovering allosteric inhibitors of the viral activity and interactions with the host receptor ACE2. The challenges of discovering allosteric modulators of the SARS-CoV-2 spike proteins are associated with the diversity of cryptic allosteric sites and complex molecular mechanisms that can be employed by allosteric ligands, including the alteration of the conformational equilibrium of spike protein and preferential stabilization of specific functional states. In the current study, we combine conformational dynamics analysis of distinct forms of the full-length spike protein trimers and …
Modeling Sex-Specific Changes In Myocardial Fibrosis, Grace Martin
Modeling Sex-Specific Changes In Myocardial Fibrosis, Grace Martin
Chemical Engineering Undergraduate Honors Theses
Heart disease the leading cause of death for both men and women in the United States. Cardiac fibrosis, or accumulation of extracellular matrix proteins in the heart, can occur after a heart attack and increase the risk for further complications. Current treatments for heart disease do not include extracellular matrix regulators, partly due to the complicated signaling network responsible for the production of these proteins. By using a computational model of the signaling network in cardia fibroblasts, the relationship between particular molecules and downstream extracellular matrix production can be examined.
Biological sex is an important factor for cardiac health and …
The Purification And Thermal Stability Of The Peroxidase Enzyme In Cucurbita Moschata, Garen Hamner
The Purification And Thermal Stability Of The Peroxidase Enzyme In Cucurbita Moschata, Garen Hamner
Senior Honors Theses
Peroxidases are enzymes that catalyze the reduction of hydrogen peroxide to water while oxidizing organic substrates and are valuable in spheres like industrial and medical applications and histochemistry. Limitations still exist in the use of the well-studied horseradish peroxidase for certain activities due to limitations like poor thermal stability, thus the search for novel peroxidases that can overcome these limitations is an active area of research. Butternut squash peroxidase (Cucurbita moschata) (BSP) shows promise due to significant activity being found in the skin and apparent enhanced thermal stability, but an efficient purification scheme for it is lacking, as well as …
Predicting Ffar4 Agonists Using Structure-Based Machine Learning Approach Based On Molecular Fingerprints, Zaid Anis Sherwani, Syeda Sumayya Tariq, Mamona Mushtaq, Ali Raza Siddiqui, Mohammad Nur-E-Alam, Aftab Ahmed, Zaheer Ul-Haq
Predicting Ffar4 Agonists Using Structure-Based Machine Learning Approach Based On Molecular Fingerprints, Zaid Anis Sherwani, Syeda Sumayya Tariq, Mamona Mushtaq, Ali Raza Siddiqui, Mohammad Nur-E-Alam, Aftab Ahmed, Zaheer Ul-Haq
Pharmacy Faculty Articles and Research
Free Fatty Acid Receptor 4 (FFAR4), a G-protein-coupled receptor, is responsible for triggering intracellular signaling pathways that regulate various physiological processes. FFAR4 agonists are associated with enhancing insulin release and mitigating the atherogenic, obesogenic, pro-carcinogenic, and pro-diabetogenic effects, normally associated with the free fatty acids bound to FFAR4. In this research, molecular structure-based machine-learning techniques were employed to evaluate compounds as potential agonists for FFAR4. Molecular structures were encoded into bit arrays, serving as molecular fingerprints, which were subsequently analyzed using the Bayesian network algorithm to identify patterns for screening the data. The shortlisted hits obtained via machine learning protocols …
Killing Cancer: Manipulating Hydrophobic Vanadium Complexes To Improve Anti-Cancer Activity, Levi Ausherman, Debbie C. Crans, Peter A. Lay, Maggi Braasch-Turi
Killing Cancer: Manipulating Hydrophobic Vanadium Complexes To Improve Anti-Cancer Activity, Levi Ausherman, Debbie C. Crans, Peter A. Lay, Maggi Braasch-Turi
SACAD: Scholarly Activities
Hydrophobic vanadium complexes have recently shown improved anti-cancer activities compared to cisplatin. The hydrophobicity and anti-proliferative activity of [VO(Hshed)(dtb)] ([Hshed= N-(salicylideneaminato)-N’-(2-hydroxyethyl)-1,2-ethanediamine and dtb= 3,5-di(tert-butyl)catechol)]) have inspired the development of a library of hydrophobic vanadium complexes. Increasing the steric bulk of the catechol ligand has been shown to have a direct impact on hydrophobicity and anti-proliferative activities. Currently at Fort Hays State University, the Braasch-Turi group is synthesizing VO(HSHED)(dtb) to build up material to support the chemical analysis and biological assay performed by our collaborators at Colorado State University and the University of Sydney, Australia, respectively. In the future, we plan …
Accurate Characterization Of Binding Kinetics And Allosteric Mechanisms For The Hsp90 Chaperone Inhibitors Using Ai-Augmented Integrative Biophysical Studies, Chao Xu, Xianglei Zhang, Lianghao Zhao, Gennady M. Verkhivker, Fang Bai
Accurate Characterization Of Binding Kinetics And Allosteric Mechanisms For The Hsp90 Chaperone Inhibitors Using Ai-Augmented Integrative Biophysical Studies, Chao Xu, Xianglei Zhang, Lianghao Zhao, Gennady M. Verkhivker, Fang Bai
Mathematics, Physics, and Computer Science Faculty Articles and Research
The binding kinetics of drugs to their targets are gradually being recognized as a crucial indicator of the efficacy of drugs in vivo, leading to the development of various computational methods for predicting the binding kinetics in recent years. However, compared with the prediction of binding affinity, the underlying structure and dynamic determinants of binding kinetics are more complicated. Efficient and accurate methods for predicting binding kinetics are still lacking. In this study, quantitative structure–kinetics relationship (QSKR) models were developed using 132 inhibitors targeting the ATP binding domain of heat shock protein 90α (HSP90α) to predict the dissociation rate …
Methionyl-Trna Synthetase Synthetic And Proofreading Activities Are Determinants Of Antibiotic Persistence, Whitney N. Wood, Miguel Angel Rubio, Lorenzo Eugenio Leiva, Gregory J. Phillips, Michael Ibba
Methionyl-Trna Synthetase Synthetic And Proofreading Activities Are Determinants Of Antibiotic Persistence, Whitney N. Wood, Miguel Angel Rubio, Lorenzo Eugenio Leiva, Gregory J. Phillips, Michael Ibba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Bacterial antibiotic persistence is a phenomenon where bacteria are exposed to an antibiotic and the majority of the population dies while a small subset enters a low metabolic, persistent, state and are able to survive. Once the antibiotic is removed the persistent population can resuscitate and continue growing. Several different molecular mechanisms and pathways have been implicated in this phenomenon. A common mechanism that may underly bacterial antibiotic persistence is perturbations in protein synthesis. To investigate this mechanism, we characterized four distinct metG mutants for their ability to increase antibiotic persistence. Two metG mutants encode changes near the catalytic site …
Mechanistic Investigation Of C—C Bond Activation Of Phosphaalkynes With Pt(0) Complexes, Roberto M. Escobar, Abdurrahman C. Ateşin, Christian Müller, William D. Jones, Tülay Ateşin
Mechanistic Investigation Of C—C Bond Activation Of Phosphaalkynes With Pt(0) Complexes, Roberto M. Escobar, Abdurrahman C. Ateşin, Christian Müller, William D. Jones, Tülay Ateşin
Research Symposium
Carbon–carbon (C–C) bond activation has gained increased attention as a direct method for the synthesis of pharmaceuticals. Due to the thermodynamic stability and kinetic inaccessibility of the C–C bonds, however, activation of C–C bonds by homogeneous transition-metal catalysts under mild homogeneous conditions is still a challenge. Most of the systems in which the activation occurs either have aromatization or relief of ring strain as the primary driving force. The activation of unstrained C–C bonds of phosphaalkynes does not have this advantage. This study employs Density Functional Theory (DFT) calculations to elucidate Pt(0)-mediated C–CP bond activation mechanisms in phosphaalkynes. Investigating the …
Β-Sheets Mediate The Conformational Change And Allosteric Signal Transmission Between The Aslov2 Termini, Sian Xiao, Mayar Terek Ibrahim, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao
Β-Sheets Mediate The Conformational Change And Allosteric Signal Transmission Between The Aslov2 Termini, Sian Xiao, Mayar Terek Ibrahim, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao
Mathematics, Physics, and Computer Science Faculty Articles and Research
Avena sativa phototropin 1 light-oxygen-voltage 2 domain (AsLOV2) is a model protein of Per-Arnt-Sim (PAS) superfamily, characterized by conformational changes in response to external environmental stimuli. This conformational change begins with the unfolding of the N-terminal A'α helix in the dark state followed by the unfolding of the C-terminal Jα helix. The light state is characterized by the unfolded termini and the subsequent modifications in hydrogen bond patterns. In this photoreceptor, β-sheets are identified as crucial components for mediating allosteric signal transmission between the two termini. Through combined experimental and computational investigations, the Hβ …
Purification And Isolation Of Α-Chloro-Β-Lactone Precursor Molecules, Matthew Ellis
Purification And Isolation Of Α-Chloro-Β-Lactone Precursor Molecules, Matthew Ellis
ASPIRE 2024
This research investigates the synthesis of α-chloro-β-lactone molecules, focusing on the production, isolation, and purification of two precursor compounds from chloroacetic acid and substituted benzaldehydes. While multiple methods were explored, including EDC, DIC, and DCC catalysis, DCC proved to be most effective in producing higher yields. However, challenges in purification arose due to the formation of byproducts, particularly with DCC, prompting further investigation for efficient extraction and purification techniques. DCC, however, shows a promising route for α-chloro-β-lactone synthesis, despite purification complexities.
Double-Blinded Randomized Control Trial Investigating The Efficacy Of Probiotic Mouth Rinse In Enhancing Oral Health, Sudeep C B Prof. Dr., Sunil P M Prof. Dr.
Double-Blinded Randomized Control Trial Investigating The Efficacy Of Probiotic Mouth Rinse In Enhancing Oral Health, Sudeep C B Prof. Dr., Sunil P M Prof. Dr.
Annual Research Symposium
The efficacy of probiotic mouth rinse in enhancing oral health was investigated through a double-blinded randomized controlled trial involving 45 children aged 12 to 15 over a two-week period. Comparing probiotic mouth rinse, chlorhexidine mouth rinse, and a control group, plaque and gingival accumulation were assessed using established indices. Results indicated both probiotic and chlorhexidine groups exhibited reduced plaque compared to the control, with the probiotic group showing superior reduction in gingival inflammation. These findings suggest the potential of probiotic mouth rinse in improving oral hygiene and overall oral health.
Spiral Wave Teleportation And Multiplex Network Synchronization In Light Sensitive Belousov-Zhabotinsky Systems, Shannyn Alicia Tyler
Spiral Wave Teleportation And Multiplex Network Synchronization In Light Sensitive Belousov-Zhabotinsky Systems, Shannyn Alicia Tyler
Graduate Theses, Dissertations, and Problem Reports (ETD)
We experimentally and computationally investigate dynamical behaviors in excitable and oscillatory media using light sensitive Belousov-Zhabotinsky (BZ) systems. These systems are not in a state of thermodynamic equilibrium, and have been proven to show various interesting phenomena including spatiotemporal patterns, self-organization, and chaos. We utilize the BZ reaction, a nonlinear chemical reaction, known for its relaxation-type oscillations, to explore the dynamics of these systems.
We examine spiral wave teleportation in an excitable media as an effective alternate defibrillation method. Spiral waves have emerged as a key phenomenon associated with the initiation and persistence of cardiac arrhythmias. Using a light sensitive …
Quantification Of Antiviral Drug Tenofovir (Tfv) By Surface-Enhanced Raman Spectroscopy (Sers) Using Cumulative Distribution Functions (Cdfs), Marguerite R. Butler, Jana Hrncirova, Meredith Clark, Sucharita Dutta, John B. Cooper
Quantification Of Antiviral Drug Tenofovir (Tfv) By Surface-Enhanced Raman Spectroscopy (Sers) Using Cumulative Distribution Functions (Cdfs), Marguerite R. Butler, Jana Hrncirova, Meredith Clark, Sucharita Dutta, John B. Cooper
Chemistry & Biochemistry Faculty Publications
Surface-enhanced Raman spectroscopy (SERS) is an ultrasensitive spectroscopic technique that generates signal-enhanced fingerprint vibrational spectra of small molecules. However, without rigorous control of SERS substrate active sites, geometry, surface area, or surface functionality, SERS is notoriously irreproducible, complicating the consistent quantitative analysis of small molecules. While evaporatively prepared samples yield significant SERS enhancement resulting in lower detection limits, the distribution of these enhancements along the SERS surface is inherently stochastic. Acquiring spatially resolved SERS spectra of these dried surfaces, we have shown that this enhancement is governed by a power law as a function of analyte concentration. Consequently, by definition, …
Synthesis Of Bis-Thioacid Derivatives Of Diarylethene And Their Photochromic Properties, Pramod Aryal, Jonathan Bietsch, Gowri Sankar Grandhi, Richard Chen, Surya B. Adhikari, Ephraiem S. Sarabamoun, Joshua J. Choi, Guijun Wang
Synthesis Of Bis-Thioacid Derivatives Of Diarylethene And Their Photochromic Properties, Pramod Aryal, Jonathan Bietsch, Gowri Sankar Grandhi, Richard Chen, Surya B. Adhikari, Ephraiem S. Sarabamoun, Joshua J. Choi, Guijun Wang
Chemistry & Biochemistry Faculty Publications
Diarylethenes (DAEs) are an important class of photoswitchable compounds that typically undergo reversible photochemical conversions between the open and closed cyclized forms upon treatment with UV light or visible light. In this study, we introduced thioacid functional groups to several photochromic dithienylethene (DTE) derivatives and established a method that can be used to prepare these photoswitchable thioacids. Four thioacid-functionalized diarylethene derivatives were synthesized through the activation of carboxylic acids with N-hydroxysuccinimide, followed by reactions with sodium hydrosulfide with yields over 90%. These derivatives exhibited reversible photoswitching and photochromic properties upon treatment with ultraviolet (UV) and visible lights. The thioacid groups …
Quantification Of Antiretroviral Drug Emtricitabine In Human Plasma By Surface Enhanced Raman Spectroscopy, Marguerite R. Butler, Terry A. Jacot, Sucharita M. Dutta, Gustavo F. Doncel, John B. Cooper
Quantification Of Antiretroviral Drug Emtricitabine In Human Plasma By Surface Enhanced Raman Spectroscopy, Marguerite R. Butler, Terry A. Jacot, Sucharita M. Dutta, Gustavo F. Doncel, John B. Cooper
Chemistry & Biochemistry Faculty Publications
In this study, reproducible label-free detection and quantification of the antiretroviral drug emtricitabine (FTC) down to 78 ng/mL in human plasma by surface enhanced Raman spectroscopy (SERS) is presented. A novel plasma sample pretreatment method using silver nitrate and silver colloidal nanoparticles (Ag CNPs) was used to prepare the plasma samples for analysis. The pretreated plasma samples were evaporated to dryness on an aluminum surface and a computer-controlled Raman scanning system was used to collect spatially resolved SERS spectra of the entire surface. Calibration curves of commercial human plasma samples containing FTC in a concentration range of 5000 to 78 …
A New Approach For Discriminating Spatially Acquired Sers Spectra Using Antiretroviral Drug Emtricitabine As A Test Sample, Jana Hrncirova, Marguerite R. Butler, Meredith R. Clark, Gustavo F. Doncel, John B. Cooper
A New Approach For Discriminating Spatially Acquired Sers Spectra Using Antiretroviral Drug Emtricitabine As A Test Sample, Jana Hrncirova, Marguerite R. Butler, Meredith R. Clark, Gustavo F. Doncel, John B. Cooper
Chemistry & Biochemistry Faculty Publications
In this study, an antiretroviral drug emtricitabine (also known as FTC or Emtriva) was detected and quantified down to 40 ng/ml by using surface-enhanced Raman spectroscopy (SERS). Its aqueous standards were tested with two types of silver nanoparticles (colloidal and dendritic) using a specially developed aluminum well plate. The SERS spectra were acquired using a Raman scanning device with 30-mu m spatial resolution. The spectral data were analyzed using a new approach for the discrimination of the spatially acquired spectra based on the Quality index (Qi). After the Qi is calculated, the spectral data are sorted based on the Qi. …
Evidence Of Direct Interaction Between Cisplatin And The Caspase-Cleaved Prostate Apoptosis Response-4 Tumor Suppressor, Krishna K. Raut, Samjhana Pandey, Gyanendra Kharel, Steven M. Pascal
Evidence Of Direct Interaction Between Cisplatin And The Caspase-Cleaved Prostate Apoptosis Response-4 Tumor Suppressor, Krishna K. Raut, Samjhana Pandey, Gyanendra Kharel, Steven M. Pascal
Chemistry & Biochemistry Faculty Publications
Prostate apoptosis response-4 (Par-4) tumor suppressor protein has gained attention as a potential therapeutic target owing to its unique ability to selectively induce apoptosis in cancer cells, sensitize them to chemotherapy and radiotherapy, and mitigate drug resistance. It has recently been reported that Par-4 interacts synergistically with cisplatin, a widely used anticancer drug. However, the mechanistic details underlying this relationship remain elusive. In this investigation, we employed an array of biophysical techniques, including circular dichroism spectroscopy, dynamic light scattering, and UV–vis absorption spectroscopy, to characterize the interaction between the active caspase-cleaved Par-4 (cl-Par-4) fragment and cisplatin. Additionally, elemental analysis was …
Polarizable Amoeba Force Field Predicts Thin And Dense Hydration Layer Around Monosaccharides, Luke A. Newman, Mackenzie G. Patton, Breyanna A. Rodriguez, Ethan W. Summer, Valerie Vaissier Welbourn
Polarizable Amoeba Force Field Predicts Thin And Dense Hydration Layer Around Monosaccharides, Luke A. Newman, Mackenzie G. Patton, Breyanna A. Rodriguez, Ethan W. Summer, Valerie Vaissier Welbourn
Chemistry & Biochemistry Faculty Publications
Polarizable force fields crucially enhance the modeling of macromolecules in polar media. Here, we present new parameters to model six common monosaccharides with the polarizable AMOEBA force field. These parameters yield a thinner, but denser, hydration layer than that previously reported. This denser hydration layer results in eliminating non-physical aggregation of glucose in water-an issue that has plagued molecular dynamics simulations of carbohydrates for decades.
Reducing Short-Chain Pfas Levels In California Water Supplies, Manu Prabandham
Reducing Short-Chain Pfas Levels In California Water Supplies, Manu Prabandham
Pomona Senior Theses
This thesis proposes twelve specific policies based on precedents set by prior regulation of persistent organic pollutants (such as PCBs), the costs and benefits of short-chain PFAS, technologies available to remove and destroy short-chain PFAS, and the roles and limitations of California’s regulatory institutions. The twelve policies are chosen to be politically and financially feasible, effective at removing short-chain PFAS from water supplies, and equitable towards lower-income and minority Californians, who suffer the most from the consequences of PFAS and other environmental pollutants. The new definitions, education campaigns, studies, taxes, bans, standards, testing, and filtration systems proposed are intended to …
Cumulative Distribution Function And Spatially Resolved Surface-Enhanced Raman Spectroscopy For The Quantitative Analysis Of Emtricitabine, Jana Hrncirova, Marguerite R. Butler, Sucharita Dutta, Meredith R. Clark, John B. Cooper
Cumulative Distribution Function And Spatially Resolved Surface-Enhanced Raman Spectroscopy For The Quantitative Analysis Of Emtricitabine, Jana Hrncirova, Marguerite R. Butler, Sucharita Dutta, Meredith R. Clark, John B. Cooper
Chemistry & Biochemistry Faculty Publications
Surface-enhanced Raman spectroscopy (SERS) has exceptional analytical sensitivity and selectivity. However, SERS irreproducibility presents an obstacle when using it for precise quantitative measurements. In this study, colloidal nanoparticles evaporated to dryness are used as a SERS active surface for the detection of the HIV drug emtricitabine (FTC; trade name Emtriva). Despite the irreproducibility of the SERS resulting from the stochastic process of evaporation, using a SERS scanning instrument, the SERS enhancement factors of spatially resolved spectra have a well-defined distribution of signals for a given analyte concentration. This distribution follows a power law function ranging from weak (very abundant signals) …
The Kinetic Modulation Of Α - Synuclein Fibrillation And Toxicity By 4-Phenylbutyric Acid, Kristos Awuah Baffour
The Kinetic Modulation Of Α - Synuclein Fibrillation And Toxicity By 4-Phenylbutyric Acid, Kristos Awuah Baffour
Graduate Theses/Dissertations
ABSTRACT
The Protein misfolding and aggregation of alpha-synuclein (α-syn) into neurotoxic amyloids underlies the pathogenesis of neurodegenerative diseases such as Parkinson's disease (PD). 4-Phenylbutyrate (PBA), an FDA drug approved for treating urea cycle disorders, has garnered significant attention as a potential chemical chaperone for targeting alpha-synuclein (α-syn) aggregation. Using in vitro assays, we demonstrated that PBA treatment alters the pattern of α-syn aggregation, as evidenced by reduced formation of oligomeric species and its increased susceptibility to proteolytic cleavage under the influence of PBA. Proteinase K assay, surface plasmon resonance, and Nile red studies indicate that PBA interacts with the extensive …