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Leveraging Bio-Inspired Molecules For Cancer Theranostics, Douglas S. MacPherson 2023 The Graduate Center, City University of New York

Leveraging Bio-Inspired Molecules For Cancer Theranostics, Douglas S. Macpherson

Dissertations, Theses, and Capstone Projects

A variety of molecules can be radiolabeled and delivered to a cancer site for the purposes of diagnostics and therapy. Among the most promising of tumor targeting molecules are peptides and antibodies. These bio-inspired molecules can be designed and synthesized to target and respond to cancer cells based on the properties of those cells. Matrix metalloproteinase (MMP) enzymes are over-expressed by some metastatic cancers, in which they are responsible for the degradation and remodeling of the extracellular matrix. In recent years, MMPs have emerged as promising targets for enzyme-responsive diagnostic probes because oligopeptides can be designed to be selectively hydrolyzed …


Second Generation Phenyloxadiazolyl Methyl Sulfones For Thiol-Specific Bioconjugations, Guillaume Dewaele-Le Roi 2023 The Graduate Center, City University of New York

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

Dissertations, Theses, and Capstone Projects

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


Structure-Based Rational Design Of Small Α-Helical Peptides With Broad-Spectrum Activity Against Multidrug-Resistant Pathogens, Sandeep Lohan, Anastasia G. Konshina, Roman G. Efremov, Innokentiy Maslennikov, Keykavous Parang 2022 Chapman University

Structure-Based Rational Design Of Small Α-Helical Peptides With Broad-Spectrum Activity Against Multidrug-Resistant Pathogens, Sandeep Lohan, Anastasia G. Konshina, Roman G. Efremov, Innokentiy Maslennikov, Keykavous Parang

Pharmacy Faculty Articles and Research

A series of small (7–12 mer) amphipathic cationic peptides were designed and synthesized to create short helical peptides with broad-range bactericidal activity and selectivity toward the bacterial cells. The analysis identified a lead 12-mer peptide 8b with broad-spectrum activity against Gram-positive (MIC = 3.1–6.2 μg/mL) and Gram-negative (MIC = 6.2–12.5 μg/mL) bacteria and selectivity toward prokaryotic versus eukaryotic cells (HC50 = 280 μg/mL, >75% cell viability at 150 μg/mL). The rapid membranolytic action of 8b was demonstrated by a calcein dye leakage assay and confirmed using scanning electron microscopy. According to circular dichroism and NMR spectroscopy, the peptides have an …


Arginine Methylation Of The Pgc-1Α C‑Terminus Is Temperature- Dependent, Meryl Mendoz, Mariel Mendoza, Tiffany Lubrino, Sidney Briski, Immaculeta Osuji, Janielle Cuala, Brendan Ly, Ivan Ocegueda, Harvey Peralta, Benjamin A. Garcia, Cecilia Zurita-Lopez 2022 California State University, Los Angeles

Arginine Methylation Of The Pgc-1Α C‑Terminus Is Temperature- Dependent, Meryl Mendoz, Mariel Mendoza, Tiffany Lubrino, Sidney Briski, Immaculeta Osuji, Janielle Cuala, Brendan Ly, Ivan Ocegueda, Harvey Peralta, Benjamin A. Garcia, Cecilia Zurita-Lopez

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We set out to determine whether the C-terminus (amino acids 481–798) of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α, UniProt Q9UBK2), a regulatory metabolic protein involved in mitochondrial biogenesis, and respiration, is an arginine methyltransferase substrate. Arginine methylation by protein arginine methyltransferases (PRMTs) alters protein function and thus contributes to various cellular processes. In addition to confirming methylation of the C-terminus by PRMT1 as described in the literature, we have identified methylation by another member of the PRMT family, PRMT7. We performed in vitro methylation reactions using recombinant mammalian PRMT7 and PRMT1 at 37, 30, 21, 18, and 4 °C. …


Designing And Synthesizing A Warhead-Fragment Inhibitory Ligand For Ivyp1 Through Fragment-Based Drug Discovery, Samuel Moore 2022 Kennesaw State University

Designing And Synthesizing A Warhead-Fragment Inhibitory Ligand For Ivyp1 Through Fragment-Based Drug Discovery, Samuel Moore

Symposium of Student Scholars

Fragment-based drug discovery (FBDD) is a powerful tool for developing anticancer and antimicrobial agents. Within this, magnetic resonance spectroscopy (NMR) provides a comprehensive qualitative and quantitative approach to screening and validating weak and robust binders with targeted proteins, making NMR among the most attractive strategies in FBDD. Inhibitor of vertebrate lysozyme (Ivyp1) of P. aeruginosa serves as an excellent target because of its active cellular location and implications in clinical prognosis for cystic fibrosis and immunocompromised patients. This study uses current NMR and biophysical techniques to develop a covalent, fragment-linked warhead inhibitor for Ivyp1 through synthetic methods, warhead linking, and …


Identification Of The Type Eleven Secretion System (T11ss) And Characterization Of T11ss-Dependent Effector Proteins, Alex S. Grossman 2022 University of Tennessee, Knoxville

Identification Of The Type Eleven Secretion System (T11ss) And Characterization Of T11ss-Dependent Effector Proteins, Alex S. Grossman

Doctoral Dissertations

Host-associated microbes live in dangerous environments as a result of host immune killing, nutrient provisioning, and physiological conditions. Bacteria have evolved a host of surface and secreted proteins to help interact with this host environment and overcome nutrient limitation. The studies included within this dissertation describe the identification of a novel bacterial secretion system which has evolved to transport these symbiosis mediating proteins. This system, termed the type eleven secretion system (T11SS), is present throughout the Gram negative phylum Proteobacteria, including many human pathogens such as Neisseria meningitidis, Acinetobacter baumanii, Haemophilus haemolyticus, and Proteus vulgaris. Furthermore, …


Oxidative Stress Strongly Restricts The Effect Of Codon Choice On The Efficiency Of Protein Synthesis In Escherichia Coli, Lorenzo Eugenio Leiva, Sara Elgamal, Sebastian A. Leidel, Omar Orellana, Michael Ibba, Assaf Katz 2022 Universidad de Chile

Oxidative Stress Strongly Restricts The Effect Of Codon Choice On The Efficiency Of Protein Synthesis In Escherichia Coli, Lorenzo Eugenio Leiva, Sara Elgamal, Sebastian A. Leidel, Omar Orellana, Michael Ibba, Assaf Katz

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Introduction

The response of enterobacteria to oxidative stress is usually considered to be regulated by transcription factors such as OxyR and SoxR. Nevertheless, several reports have shown that under oxidative stress the levels, modification and aminoacylation of tRNAs may be altered suggesting a role of codon bias in regulation of gene expression under this condition.

Methods

In order to characterize the effects of oxidative stress on translation elongation we constructed a library of 61 plasmids, each coding for the green fluorescent protein (GFP) translationally fused to a different set of four identical codons.

Results

Using these reporters, we observed that …


Membrane-Active Cyclic Amphiphilic Peptides: Broad-Spectrum Antibacterial Activity Alone And In Combination With Antibiotics, Eman H. M. Mohammed, Sandeep Lohan, Tarra Ghaffari, Shilpi Gupta, Rakesh K. Tiwari, Keykavous Parang 2022 Chapman University

Membrane-Active Cyclic Amphiphilic Peptides: Broad-Spectrum Antibacterial Activity Alone And In Combination With Antibiotics, Eman H. M. Mohammed, Sandeep Lohan, Tarra Ghaffari, Shilpi Gupta, Rakesh K. Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

We designed a library of 24 cyclic peptides containing arginine (R) and tryptophan (W) residues in a sequential manner [RnWn] (n = 2–7) to study the impact of the hydrophilic/hydrophobic ratio, charge, and ring size on the antibacterial activity against Gram-positive and Gram-negative strains. Among peptides, 5a and 6a demonstrated the highest antimicrobial activity. In combination with 11 commercially available antibiotics, 5a and 6a showed remarkable synergism against a large panel of resistant pathogens. Hemolysis (HC50 = 340 μg/mL) and cell viability against mammalian cells demonstrated the selective lethal action of 5a against bacteria over …


Protein Phosphatase 2a Regulates Xanthine Oxidase-Derived Ros Production In Macrophages And Influx Of Inflammatory Monocytes In A Murine Gout Model, Sandy Elsayed, Khaled A. Elsaid 2022 Chapman University

Protein Phosphatase 2a Regulates Xanthine Oxidase-Derived Ros Production In Macrophages And Influx Of Inflammatory Monocytes In A Murine Gout Model, Sandy Elsayed, Khaled A. Elsaid

Pharmacy Faculty Articles and Research

Background: Gout is a common arthritis, due to deposition of monosodium urate (MSU) crystals which results in IL-1β secretion by tissue-resident macrophages. Xanthine oxidase (XO) catalyzes uric acid (UA) production and in the process, reactive oxygen species (ROS) are generated which contributes to NLRP3 inflammasome activation. Protein phosphatase 2A (PP2A) may be involved in regulating inflammatory pathways in macrophages. The objective of this study was to investigate whether PP2A regulates gout inflammation, mediated by XO activity modulation. We studied UA and ROS generations in MSU stimulated murine bone marrow derived macrophages (BMDMs) in response to fingolimod phosphate, a PP2A activator, …


Differential Expression And Activities Of Cytochrome P450 3a In The Rat Brain Microsomes And Mitochondria, Nouf Alshammari, Devaraj Venkatapura Chandrashekar, Mamunur Rashid, Reza Mehvar 2022 Chapman University

Differential Expression And Activities Of Cytochrome P450 3a In The Rat Brain Microsomes And Mitochondria, Nouf Alshammari, Devaraj Venkatapura Chandrashekar, Mamunur Rashid, Reza Mehvar

Pharmacy Faculty Articles and Research

Midazolam (MDZ), a benzodiazepine derivative, is metabolized to 1′- and 4-hydroxylated metabolites (1′-OH-MDZ and 4-OH-MDZ, respectively) by cytochrome P450 3A (CYP3A). The purpose of this study was to investigate the CYP3A-mediated hydroxylation of MDZ in the rat brain mitochondria (MT). Brain microsomes (MC) and MT fractions were prepared from rats (n = 8) using differential and density gradient centrifugations, and the purity of the fractions was evaluated using VDAC1 and calreticulin as markers of MT and MC, respectively. The formation rates of 1′-OH-MDZ and 4-OH-MDZ in the rat brain MC and MT samples were determined using an LC–MS/MS method …


Gutka Consumption And Dietary Partialities Explaining Anemia In Women Of A Coastal Slum Of Karachi, Pakistan: A Mixed-Method Study, Ameer Muhammad, Sarah Saleem, Daniyaal Ahmad, Eleze Tariq, Yasir Shafiq 2022 VITAL Pakistan Trust, Pakistan

Gutka Consumption And Dietary Partialities Explaining Anemia In Women Of A Coastal Slum Of Karachi, Pakistan: A Mixed-Method Study, Ameer Muhammad, Sarah Saleem, Daniyaal Ahmad, Eleze Tariq, Yasir Shafiq

Community Health Sciences

Background: Limited literature is available on the dietary pattern and its consequences on health of women living in coastal slums of Karachi, Pakistan.
Material and methods: The study employed a mixed-method approach where concurrent quantitative and qualitative assessments were carried out. An analytical cross-sectional survey was conducted to collect information on demographic, household, obstetrics characteristics, and dietary pattern of married women of reproductive age (MWRA). Blood samples were collected to identify the hemoglobin level to determine anemia. For the qualitative component, focus group discussions were carried out with women and in-depth interviews with shopkeepers to understand the availability of food …


Identification And Characterization Of Epicuticular Proteins Of Nematodes Sharing Motifs With Cuticular Proteins Of Arthropods, Bruno Betschart, Marco Bisoffi, Ferial Alaeddine 2022 University of Neuchâtel

Identification And Characterization Of Epicuticular Proteins Of Nematodes Sharing Motifs With Cuticular Proteins Of Arthropods, Bruno Betschart, Marco Bisoffi, Ferial Alaeddine

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Specific collagens and insoluble proteins called cuticlins are major constituents of the nematode cuticles. The epicuticle, which forms the outermost electron-dense layer of the cuticle, is composed of another category of insoluble proteins called epicuticlins. It is distinct from the insoluble cuticlins localized in the cortical layer and the fibrous ribbon underneath lateral alae. Our objective was to identify and characterize genes and their encoded proteins forming the epicuticle. The combination between previously obtained laboratory results and recently made available data through the whole-genome shotgun contigs (WGS) and the transcriptome Shotgun Assembly (TSA) sequencing projects of Ascaris suum allowed us …


Biomedical Applications Of Protein Films And Polymeric Nanomaterials, Sanjana Gopalakrishnan 2022 University of Massachusetts Amherst

Biomedical Applications Of Protein Films And Polymeric Nanomaterials, Sanjana Gopalakrishnan

Doctoral Dissertations

Biomaterials are widely applied for the diagnosis and treatment of numerous diseases. In addition to fulfilling specific biological functions, biomaterials must also be non-toxic, biocompatible, and sterilizable to be regarded as safe-for-use. Polymers are excellent candidates for fabricating functional biomaterials due to their wide availability and varied properties and may be natural or synthetic. Polymer precursors are fabricated into coatings, foams, scaffolds, gels, composites, and nanomaterials for several biomedical applications. This dissertation focuses on two types of polymeric biomaterials – protein-based materials and synthetic polymeric nanoparticles. Proteins are biopolymers that naturally occur with a variety of structural and functional properties. …


Detailing The Effects Of Cbd On Parp And Survivin Expression In Ewing Sarcoma, Tyler Carter 2022 Jacksonville State University

Detailing The Effects Of Cbd On Parp And Survivin Expression In Ewing Sarcoma, Tyler Carter

Theses

Ewing sarcoma (ES) is an aggressive pediatric bone cancer with low five-year survival rates, particularly with recurrent disease because ES often becomes resistant to chemotherapy in these recurrences. Cannabidiol (CBD) has been identified as a potentially promising therapeutic for patients with ES. In other cancer types, CBD has demonstrated effects on two major proteins that contribute to chemotherapy resistance. The first, Poly (ADP-ribose) Polymerase I (PARP1), is a DNA damage repair enzyme that is overexpressed in recurrent ES. Though chemotherapy induces DNA damage in these cancer cells, the high levels of PARP1 facilitate repair of the DNA, allowing the mutated …


Interpretable Machine Learning Models For Molecular Design Of Tyrosine Kinase Inhibitors Using Variational Autoencoders And Perturbation-Based Approach Of Chemical Space Exploration, Keerthi Krishnan, Ryan Kassab, Steve Agajanian, Gennady M. Verkhivker 2022 Chapman University

Interpretable Machine Learning Models For Molecular Design Of Tyrosine Kinase Inhibitors Using Variational Autoencoders And Perturbation-Based Approach Of Chemical Space Exploration, Keerthi Krishnan, Ryan Kassab, Steve Agajanian, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

In the current study, we introduce an integrative machine learning strategy for the autonomous molecular design of protein kinase inhibitors using variational autoencoders and a novel cluster-based perturbation approach for exploration of the chemical latent space. The proposed strategy combines autoencoder-based embedding of small molecules with a cluster-based perturbation approach for efficient navigation of the latent space and a feature-based kinase inhibition likelihood classifier that guides optimization of the molecular properties and targeted molecular design. In the proposed generative approach, molecules sharing similar structures tend to cluster in the latent space, and interpolating between two molecules in the latent space …


Statins: Masked Anti-Epileptic Warriors, Govinda Khatri, priya Kotak, Ayush Kumar, Mohammad Mehedi Hasan 2022 Dow University of Health Sciences, Pakistan

Statins: Masked Anti-Epileptic Warriors, Govinda Khatri, Priya Kotak, Ayush Kumar, Mohammad Mehedi Hasan

Medical College Documents

No abstract provided.


In-Silico Analysis Of Interacting Pathways Through Kim-1 Protein Interaction In Diabetic Nephropathy, Fatima Abid, Z Rubab, Syeda Sadia Fatima, A Qureshi, Arfa Azhar, A Jafri 2022 Jinnah Sindh Medical University, Karachi

In-Silico Analysis Of Interacting Pathways Through Kim-1 Protein Interaction In Diabetic Nephropathy, Fatima Abid, Z Rubab, Syeda Sadia Fatima, A Qureshi, Arfa Azhar, A Jafri

Department of Biological & Biomedical Sciences

Background: Human Kidney Injury Molecule-1, also known as HAVCR-1 (Hepatitis A virus cellular receptor 1), belongs to the cell-surface protein of immunoglobulin superfamily involved in the phagocytosis by acting as scavenger receptor epithelial cells. The study focused on pinpointing the mechanisms and genes that interact with KIM-1.
Methods: This in-silico study was done from March 2019 to December 2019. The Enrichment and protein-protein interaction (PPI) network carefully choose proteins. In addition, the diagramed gene data sets were accomplished using FunRich version 3.1.3. It was done to unveil the proteins that may affect the regulation of HAVCR1 or may be regulated …


Synthesis And Evaluation Of Anti-Hiv Activity Of Mono- And Di-Substituted Phosphonamidate Conjugates Of Tenofovir, Aaminat Qureshi, Louise A. Ouattara, Naglaa Salem El-Sayed, Amita Verma, Gustavo F. Doncel, Muhammad Iqbal Choudhary, Hina Siddiqui, Keykavous Parang 2022 University of Karachi

Synthesis And Evaluation Of Anti-Hiv Activity Of Mono- And Di-Substituted Phosphonamidate Conjugates Of Tenofovir, Aaminat Qureshi, Louise A. Ouattara, Naglaa Salem El-Sayed, Amita Verma, Gustavo F. Doncel, Muhammad Iqbal Choudhary, Hina Siddiqui, Keykavous Parang

Pharmacy Faculty Articles and Research

The activity of nucleoside and nucleotide analogs as antiviral agents requires phosphorylation by endogenous enzymes. Phosphate-substituted analogs have low bioavailability due to the presence of ionizable negatively-charged groups. To circumvent these limitations, several prodrug approaches have been proposed. Herein, we hypothesized that the conjugation or combination of the lipophilic amide bond with nucleotide-based tenofovir (TFV) (1) could improve the anti-HIV activity. During the current study, the hydroxyl group of phosphonates in TFV was conjugated with the amino group of L-alanine, L-leucine, L-valine, and glycine amino acids and other long fatty ester hydrocarbon chains to synthesize 43 derivatives. Several …


Integrating Conformational Dynamics And Perturbation-Based Network Modeling For Mutational Profiling Of Binding And Allostery In The Sars-Cov-2 Spike Variant Complexes With Antibodies: Balancing Local And Global Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan 2022 Chapman University

Integrating Conformational Dynamics And Perturbation-Based Network Modeling For Mutational Profiling Of Binding And Allostery In The Sars-Cov-2 Spike Variant Complexes With Antibodies: Balancing Local And Global Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan

Mathematics, Physics, and Computer Science Faculty Articles and Research

n this study, we combined all-atom MD simulations, the ensemble-based mutational scanning of protein stability and binding, and perturbation-based network profiling of allosteric interactions in the SARS-CoV-2 spike complexes with a panel of cross-reactive and ultra-potent single antibodies (B1-182.1 and A23-58.1) as well as antibody combinations (A19-61.1/B1-182.1 and A19-46.1/B1-182.1). Using this approach, we quantify the local and global effects of mutations in the complexes, identify protein stability centers, characterize binding energy hotspots, and predict the allosteric control points of long-range interactions and communications. Conformational dynamics and distance fluctuation analysis revealed the antibody-specific signatures of protein stability and flexibility of the …


Emicizumab-Kxwh: A Critical Review, Kiera O'Leary 2022 Munster Technological University, Rossa Ave, Bishopstown, Cork, Ireland, T12 P928

Emicizumab-Kxwh: A Critical Review, Kiera O'Leary

International Undergraduate Journal of Health Sciences

The first descriptions of haemophilia A were reported in the second century AD, with the first modern description by John Conrad Otto in 1803. Historically, the natural history of haemophilia A was associated with very high rates morbidity and mortality, often following trivial accidents. Although treatment options for haemophilia A have been revolutionised in recent decades, haemophilia A remains a hereditary disease of concern and factor replacement products remain the mainstay of treatment.

As such, patients with haemophilia can carry huge burdens, particularly when a complication such as a FVIII inhibitor is present. A recently approved novel therapeutic, Emicizumab-kxwh, has …


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