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Prostate Tissue Motion Tracking And Ultrasound Elastography Using Tissue Mechanics Derived Constraints, Tristan S. Curry 2024 Western University

Prostate Tissue Motion Tracking And Ultrasound Elastography Using Tissue Mechanics Derived Constraints, Tristan S. Curry

Electronic Thesis and Dissertation Repository

Current prostate cancer detection methods can be costly to obtain, such as magnetic resonance imaging, or lack specificity, such as a digital rectal exam. Ultrasound elastography, a method that can be used to develop and test algorithms that output stiffness, strain, and displacement data captured by ultrasound radio frequency readings, offers a potential solution to these challenges. An initial algorithm utilizing dynamic programming and analytic minimization estimates the radial and angular displacements from a pre- and post-compression data set to determine the required material properties. This estimate of displacements is then refined through an algorithm where incompressibility, Laplacian smoothing, and …


The Role Of Efflux Pump Inhibitor In Enhancing Antimicrobial Efficiency Of Silver Nanoparticles And Methylene Blue As An Effective Photodynamic Therapy Agent, Yaran Allamyradov 2024 Western Kentucky University

The Role Of Efflux Pump Inhibitor In Enhancing Antimicrobial Efficiency Of Silver Nanoparticles And Methylene Blue As An Effective Photodynamic Therapy Agent, Yaran Allamyradov

Masters Theses & Specialist Projects

Efflux pumps are critical active transport systems utilized by cells to expel toxic substances, including antibiotics and photosensitizer complexes, thereby contributing to antimicrobial resistance. Efflux pump inhibitors (EPIs), which are compounds that obstruct the transport of molecules through these pumps, play a pivotal role in enhancing the effectiveness of antimicrobial therapies against pathogens. This study investigates the effects of the EPI reserpine on the photodeactivation rate of pathogens when used in conjunction with silver nanoparticles (Ag NPs) and methylene blue (MB), a common photosensitizer.

Our research reveals that the application of reserpine, in combination with Ag NPs and MB, leads …


Characterizing Gsk3Β Interaction And Kinetics Via Isothermal Titration Calorimetry, W A Bhagya De Silva 2024 University of Nevada, Las Vegas

Characterizing Gsk3Β Interaction And Kinetics Via Isothermal Titration Calorimetry, W A Bhagya De Silva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Glycogen synthase kinase 3β (GSK3β) is a multifunctional serine/threonine kinase involved in several key signaling pathways, including glycogen metabolism, WNT/β-catenin, and Hedgehog signaling. Hyperactivity of GSK3β has been linked to Alzheimer’s disease, bipolar disorder, type II diabetes, and some cancers. Therefore, GSK3β is of interest as a target for therapeutics. Lithium ion (Li+) is a classical inhibitor of GSK3β. Structurally similar beryllium ion (Be2+) is ~1000-fold more potent. Lithium and beryllium have demonstrated pathway-specific and cell type-specific inhibition of GSK3β, prompting an investigation into the inhibitory mechanisms and thermodynamic characteristics of the metal-enzyme interaction.Isothermal titration calorimetry (ITC) is a label-free …


Structural Analysis Of Dj-1 Glyoxalase Activity By Mix-And-Inject Serial Synchrotron Crystallography, Coleman Dolamore 2024 University of Nebraska-Lincoln

Structural Analysis Of Dj-1 Glyoxalase Activity By Mix-And-Inject Serial Synchrotron Crystallography, Coleman Dolamore

Department of Biochemistry: Dissertations, Theses, and Student Research

Observing enzyme structures while they are catalyzing a reaction has been a major goal of both enzymology and structural biology for decades. With the advent of time-resolved serial X-ray crystallography using X-ray free electron lasers (XFELs) and synchrotron sources, enzyme reactions can be monitored in real time in crystallo. Here, we use two different approaches to study related enzymes involved in methylglyoxal detoxification. For human DJ-1, we used pink beam mix-and-inject serial crystallography (MISC) at the Advanced Photon Source (BioCARS 14-ID) to probe the controversial mechanism of DJ-1’s action on methylglyoxal by using serial Laue diffraction. The high flux …


Microstructural Mri Evolution During Adult Mouse Brain Maturation And Concussion Recovery, Naila Rahman 2024 The University of Western Ontario

Microstructural Mri Evolution During Adult Mouse Brain Maturation And Concussion Recovery, Naila Rahman

Electronic Thesis and Dissertation Repository

Mild traumatic brain injury (mTBI), also called concussion, has become a significant public health concern. Current clinical neuroimaging techniques lack the sensitivity and specificity required to reliably detect signs of concussion, as large-scale changes are absent. Diffusion magnetic resonance imaging (dMRI) has arguably had the greatest influence to-date of neuroimaging modalities in mTBI, but previous studies have reported inconsistent findings, as standard dMRI lacks specificity and provides a limited model of neuroanatomy. This thesis explores the application of microstructural MR methods, that go beyond standard dMRI to improve sensitivity and specificity, to a preclinical model of mTBI and adult brain …


Assessing The Pre- And Post-Synaptic Effects Of Opioids On Inspiratory Rhythmogenesis, Jingzhi Zhao, Diego Morandi Zerpa 2024 William & Mary

Assessing The Pre- And Post-Synaptic Effects Of Opioids On Inspiratory Rhythmogenesis, Jingzhi Zhao, Diego Morandi Zerpa

Biology and Medicine Through Mathematics Conference

No abstract provided.


The Interactions Of Centromeric Nucleosomes Elucidated By Atomic Force Microscopy, Shaun Filliaux 2024 University of Nebraska Medical Center

The Interactions Of Centromeric Nucleosomes Elucidated By Atomic Force Microscopy, Shaun Filliaux

Theses & Dissertations

Nucleosomes are the fundamental unit of compaction for DNA in the genome. These positively charged proteins have two main types of nucleosomes: canonical (H3 containing) and centromere (CENP-A containing). The compacting of DNA allows for DNA to fit into the nucleus of cells, but creates a barrier for DNA accessibility for operations such as replication or transcription. Centromeric chromatin is a subset of chromatin structure and governs chromosome segregation. Compared to the bulk chromosome, centromeres are composed of H3 and CENP-A nucleosomes in which H3 histones is replaced by its homolog CENP-A histone. This results in nucleosomes with different structures, …


Intrinsically Disordered Proteins And Their Role In Biomolecular Condensates, Danielle Latham 2024 Clemson University

Intrinsically Disordered Proteins And Their Role In Biomolecular Condensates, Danielle Latham

All Dissertations

Proteins are biomacromolecules responsible for the functions of life. While classically proteins are thought to be well structured in order to perform a specific function, 50% of proteins within Eukaryotic cells contain intrinsically disordered regions (IDRs), regions with no well-defined structure. IDRs are often used for cell signaling, responding to external factors such as temperature changes or the presence of small molecules. To understand how IDRs can function without structure, it is important to understand the dynamics of such systems. Understanding IDR intramolecular and intermolecular interactions will shed light on IDR dynamics. Intramolecular interactions are first explored using fluorescence spectroscopy …


Assessing Nordihydroguaiaretic Acid Properties And Its Potential Therapeutic Effect For Glioblastoma, Jose Arturo Guerrero 2024 University of Texas at El Paso

Assessing Nordihydroguaiaretic Acid Properties And Its Potential Therapeutic Effect For Glioblastoma, Jose Arturo Guerrero

Open Access Theses & Dissertations

This study employs a combination of theoretical and experimental analysis to spectroscopically investigate the biomechanistic structure relationship and therapeutic effects of the Nordihydroguaiaretic Acid (NDGA) chemical derived from the Larrea Tridentata plant. These relationships are crucial for understanding NDGA's efficacy in disease prevention, treatment, and potential toxicological effects. While the medicinal and antiviral properties of the NDGA have been studied extensively, there remains a gap in optically identifying and reporting its structural changes. The current research successfully reveals evident trends in NDGA's vibrational signatures, particularly highlighting the absence of the Raman feature at 780 〖cm〗^(-1) as indicative of a fully …


Computational Study Of Confined Cytoskeletal Assemblies: Simple Rules, Complex Behavior, Oghosa Honor Akenuwa 2024 University of Tennessee, Knoxville

Computational Study Of Confined Cytoskeletal Assemblies: Simple Rules, Complex Behavior, Oghosa Honor Akenuwa

Doctoral Dissertations

The actin cytoskeleton is crucial for cellular processes and proper organization in cells. Physical regulators like actin crosslinking proteins, molecular motors, and physical confinement significantly impact the organization of the actin cytoskeleton. Despite advances, much remains unknown about how these physical regulators affect actin organization. In this thesis, we employ coarse-grained computer simulations to investigate the effect of physical regulators on the dynamics and organization of semiflexible actin filaments. First, we explore the role of crosslinker properties and confinement shape on actin organization by varying the system shape, the number and type of crosslinking proteins, and the length of filaments. …


Implementing Fret Spectrometry Using Time Resolved Fluorescence Microscopy For Determination Of Protein Oligomer Size And Geometry In Live Cells, Aliyah Sephrah Khan 2024 University of Wisconsin-Milwaukee

Implementing Fret Spectrometry Using Time Resolved Fluorescence Microscopy For Determination Of Protein Oligomer Size And Geometry In Live Cells, Aliyah Sephrah Khan

Theses and Dissertations

Fӧrster or Fluorescence Resonance Energy Transfer (FRET) is a biological phenomenon that occurs when energy is transferred non-radiatively from an excited donor molecule to an unexcited acceptor molecule when they are a certain distance from each other. One method of conducting FRET experiments is using FRET spectrometry which was previously introduced by the Raicu Lab. This method generates histograms of FRET efficiencies at pixel level called FRET spectrograms, that are fitted with models to determine the quaternary structure of protein oligomers as opposed to traditional FRET experiments which average over all FRET efficiencies. Currently, FRET spectrometry is implemented with spectrally …


An Investigation Into The Structural Features That Control Factor Xiii Stability And Substrate Specificity., Rameesa Darul Amne Syed Mohammed 2024 University of Louisville

An Investigation Into The Structural Features That Control Factor Xiii Stability And Substrate Specificity., Rameesa Darul Amne Syed Mohammed

Electronic Theses and Dissertations

Factor XIII (FXIII) is a transglutaminase enzyme with multiple physiological roles that is found in plasma and cells of bone marrow origin. The catalytic A subunit (FXIII-A) is made of an N-terminal activation peptide (AP), β-sandwich, catalytic core, and two β-barrel domains. FXIII crosslinks the sidechains of glutamine (Q) and lysine (K) residues across plasmatic and cellular substrates. Because of its involvement in clot stabilization and determining fibrin clot size, FXIII-A is regarded as a target for developing new anticoagulants with minimal bleeding risks. However, the FXIII-A structural features that control its stability and substrate specificity largely remain unknown. Plasma …


Coomassie Brilliant Blue Dye As A Method For Analyzing Fracture Markings In Bone, Abigail Hoffmeister, David Harutunyan, Matthew Aizawa, Everett Baker, Brandon Mendoza, Chase Freeman, Siran Iskanian 2024 Pepperdine University

Coomassie Brilliant Blue Dye As A Method For Analyzing Fracture Markings In Bone, Abigail Hoffmeister, David Harutunyan, Matthew Aizawa, Everett Baker, Brandon Mendoza, Chase Freeman, Siran Iskanian

Seaver College Research And Scholarly Achievement Symposium

Coomassie Brilliant Blue Dye is a dye commonly used to stain proteins. Because of its ability to adhere to proteins, this research has focused on perfecting a method of dyeing a fractured flat bone in order to most accurately observe and analyze fracture markings within the trabecular layer. Stereoscopic microscopy was the chosen technique of analysis for this research because of its proven effectiveness in glass and ceramic fractography to observe varying depths. In order to most effectively apply stereoscopic microscopy to this research, the following variables were manipulated to maximize color contrast in the trabecular layer in order to …


Development Of An Integrated Workflow For Nucleosome Modeling And Simulations, Ran Sun 2024 Louisiana Tech University

Development Of An Integrated Workflow For Nucleosome Modeling And Simulations, Ran Sun

Doctoral Dissertations

Nucleosomes are the building blocks of eukaryotic genomes and thus fundamental to to all genetic processes. Any protein or drug that binds DNA must either cooperate or compete with nucleosomes. Given that a nucleosome contains 147 base pairs of DNA, there are approximately 4^147 or 10^88 possible sequences for a single nucleosome. Exhaustive studies are not possible. However, genome wide association studies can identify individual nucleosomes of interest to a specific mechanism, and today's supercomputers enable comparative simulation studies of 10s to 100s of nucleosomes. The goal of this thesis is to develop and present and end-to-end workflow that serves …


Identification Of Regulatory Elements In The Untranslated Regions Of Streptolysin S Associated Gene A Messenger Rna From Group A Streptococcus, Cameron R. Carroll, Sara G. Nibar, Alexis S. Brown, Lauren R. Angello, Gabriela C. Pérez-Alvarado, Brian M. Lee 2024 Coastal Carolina University

Identification Of Regulatory Elements In The Untranslated Regions Of Streptolysin S Associated Gene A Messenger Rna From Group A Streptococcus, Cameron R. Carroll, Sara G. Nibar, Alexis S. Brown, Lauren R. Angello, Gabriela C. Pérez-Alvarado, Brian M. Lee

Journal of the South Carolina Academy of Science

Streptococcus pyogenes, also known as group A Streptococcus (GAS), is a human pathogen associated with a variety of diseases such as strep throat, scarlet fever, toxic shock syndrome, and necrotizing fasciitis. One of the virulence factors released by GAS during an invasive infection is a cytotoxic peptide, streptolysin S (SLS), which inhibits the immune response to necrotizing fasciitis. The streptolysin S associated gene A product, SagA, is modified to produce SLS. Thesag operon includes sagA and the genes required for enzyme-mediated post-translational modifications of SagA and the export of SLS. The sagA gene is contained within the pleiotropic …


Transparent And Conductive Gallium Oxide Electrode For Simultaneous Recording And Optogenetic Stimulation, Christopher Patrick Carey 2024 West Virginia University

Transparent And Conductive Gallium Oxide Electrode For Simultaneous Recording And Optogenetic Stimulation, Christopher Patrick Carey

Graduate Theses, Dissertations, and Problem Reports

Neural electrode technology has been around for centuries since the times of Galvani. In early electrophysiology experiments metal wires were used to induce contractions in dissected animals. The metal wire electrode has since been a standard tool to both stimulate and record neural activity. In the past two decades, a new strategy for neural stimulation has been formulated based on the emergent field of optogenetics. Optogenetics refers to the use of light-sensitive proteins genetically imbedded in the membrane of a neuron to elicit neural activity. This technique offers more selectivity in the stimulation of neurons. Typical optogenetic neural electrodes, or …


Mathematical Modeling Of Microscale Biology In Polyelectrolyte Brushes, William J. Ceely 2024 Claremont Graduate University

Mathematical Modeling Of Microscale Biology In Polyelectrolyte Brushes, William J. Ceely

CGU Theses & Dissertations

Biological macromolecules including nucleic acids, proteins, and glycosaminoglycans are typically anionic and can span domains of up to hundreds of nanometers and even micron length scales. The structures exist in crowded environments that are dominated by multivalent electrostatic interactions that can be modeled using mean-field continuum approaches that represent underlying molecular nanoscale biophysics. In this thesis, we develop such models for polyelectrolyte brushes using both steady state modified Poisson-Boltzmann models and transient modified Poisson-Nernst-Planck models that incorporate important ion-specific (Hofmeister) effects. The transient model enables observation of the relative physical effects as an initial non-equilibrium state relaxes to the steady …


Compliance And Roughness In Relation To Gecko Locomotion, Brooklynn Campbell 2024 The University of Akron

Compliance And Roughness In Relation To Gecko Locomotion, Brooklynn Campbell

Williams Honors College, Honors Research Projects

Geckos move efficiently through a variety of substrates, from swaying branches to wooden fences to the sides of structures. Previous studies have studied locomotion and adhesion on manmade and rough substrates; however, the work is limited when discussing locomotion and adhesion as a relationship of compliance and roughness. Ease of movement was quantified by speed, under the assumption that the faster a gecko moves, the easier it is for the gecko to cross the substrate. Gehyra oceanica geckos from Moorea, French Polynesia were tested on substrates varying in compliance and roughness with four different treatments in total. Compliance, roughness, and …


Detecting Interactions Between Mps3 In Linc Complex And Ndj1 In Nuclear Pore Complex In Mechanically Stressed Yeast, Dean Boecher, Rebecca Adams 2024 Belmont University

Detecting Interactions Between Mps3 In Linc Complex And Ndj1 In Nuclear Pore Complex In Mechanically Stressed Yeast, Dean Boecher, Rebecca Adams

Belmont University Research Symposium (BURS)

The mechanisms of how mechanical stress is translated into cellular action and structural reorganization within the nuclear envelope are largely unexplored. The Linker of Nucleoskeleton and Cytoskeleton (LINC) complex is a transmembrane protein complex that connects the actin cytoskeleton to the lamin nucleoskeleton, enabling mechanical forces to be translated between the cytoplasm and the nucleus. A better understanding of the translation of physical forces into cell responses can be gained through confirming the existence of interactions between LINC complex proteins and nuclear pore complexes (NPCs), which control the exchange of biochemical signals and macromolecules in and out of the nucleus …


Quantitative Raman Analysis Of Human Blood Serum Of Glaucoma Patients Supplemented With Macular Pigment Carotenoids., Joy Udensi, Ekaterina Loskutova, James Loughman, Hugh J. Byrne 2024 Technological University Dublin

Quantitative Raman Analysis Of Human Blood Serum Of Glaucoma Patients Supplemented With Macular Pigment Carotenoids., Joy Udensi, Ekaterina Loskutova, James Loughman, Hugh J. Byrne

Datasets

Carotenoids have been widely studied for their high dietary, antioxidant, and vision protection roles in the human body. Blood contains all major dietary carotenoids and hence presents as a suitable and efficient substrate for the estimation of dietary carotenoids in vivo. Following the 18-month supplementation of open angle glaucoma patients with macula pigment carotenoids (Lutein, Zeaxanthin and Meso-Zeaxanthin) in the European Nutrition in Glaucoma Management (ENIGMA) trial, Raman spectroscopic analysis of the pre-supplementation baseline and 18-month supplemented blood serum carotenoids from participants was carried out, to investigate the systemic impact of supplementation in the blood and explore a more direct …


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