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Amino Acids, Peptides, and Proteins Commons

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Cyclic Dipeptides: The Biological And Structural Landscape With Special Focus On The Anti-Cancer Proline-Based Scaffold, Joanna Bojarska, Adam Mieczkowski, Zyta M. Ziora, Mariusz Skwarczynski, Istvan Toth, Ahmed O. Shalash, Keykavous Parang, Shaima Ahmed El-Mowafi, Eman H. M. Mohammed, Sherif Elnagdy, Maha AlKhazindar, Wojciech M. Wolf 2021 Technical University of Lodz

Cyclic Dipeptides: The Biological And Structural Landscape With Special Focus On The Anti-Cancer Proline-Based Scaffold, Joanna Bojarska, Adam Mieczkowski, Zyta M. Ziora, Mariusz Skwarczynski, Istvan Toth, Ahmed O. Shalash, Keykavous Parang, Shaima Ahmed El-Mowafi, Eman H. M. Mohammed, Sherif Elnagdy, Maha Alkhazindar, Wojciech M. Wolf

Pharmacy Faculty Articles and Research

Cyclic dipeptides, also know as diketopiperazines (DKP), the simplest cyclic forms of peptides widespread in nature, are unsurpassed in their structural and bio-functional diversity. DKPs, especially those containing proline, due to their unique features such as, inter alia, extra-rigid conformation, high resistance to enzyme degradation, increased cell permeability, and expandable ability to bind a diverse of targets with better affinity, have emerged in the last years as biologically pre-validated platforms for the drug discovery. Recent advances have revealed their enormous potential in the development of next-generation theranostics, smart delivery systems, and biomaterials. Here, we present an updated review on the …


Exogenous Surfactant As A Delivery Vehicle For Intrapulmonary Therapeutics, Brandon J. Baer 2021 The University of Western Ontario

Exogenous Surfactant As A Delivery Vehicle For Intrapulmonary Therapeutics, Brandon J. Baer

Electronic Thesis and Dissertation Repository

As an organ system, the lung has unique advantages and disadvantages for direct drug delivery. Its contact with the external environment allows for the airways to be easily accessible to intrapulmonary delivery. However, its complex structure, which divides into more narrow airways with each branch, can make direct delivery to the remote alveoli challenging. The objective of this thesis was to overcome this issue by using exogenous surfactant, a lipoprotein complex used to treat neonatal respiratory distress syndrome, as a carrier for pulmonary therapeutics. It was hypothesized that therapeutics administered with a surfactant vehicle would display enhanced delivery to the …


Atomistic Simulations And In Silico Mutational Profiling Of Protein Stability And Binding In The Sars-Cov-2 Spike Protein Complexes With Nanobodies: Molecular Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Deniz Yasar Oztas, Grace Gupta 2021 Chapman University

Atomistic Simulations And In Silico Mutational Profiling Of Protein Stability And Binding In The Sars-Cov-2 Spike Protein Complexes With Nanobodies: Molecular Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Deniz Yasar Oztas, Grace Gupta

Mathematics, Physics, and Computer Science Faculty Articles and Research

Structure-functional studies have recently revealed a spectrum of diverse high-affinity nanobodies with efficient neutralizing capacity against SARS-CoV-2 virus and resilience against mutational escape. In this study, we combine atomistic simulations with the ensemble-based mutational profiling of binding for the SARS-CoV-2 S-RBD complexes with a wide range of nanobodies to identify dynamic and binding affinity fingerprints and characterize the energetic determinants of nanobody-escaping mutations. Using an in silico mutational profiling approach for probing the protein stability and binding, we examine dynamics and energetics of the SARS-CoV-2 complexes with single nanobodies Nb6 and Nb20, VHH E, a pair combination VHH E + …


Prenatal Diagnosis Of Maternal Serum From Mothers Carrying Β-Thalassemic Fetus, Yumna Fazal, Muhammad Zohaib, Basir Syed, Saqib H. Ansari, Zehra Hashim, Aftab Ahmed, Shamshad Zarina 2021 University of Karachi

Prenatal Diagnosis Of Maternal Serum From Mothers Carrying Β-Thalassemic Fetus, Yumna Fazal, Muhammad Zohaib, Basir Syed, Saqib H. Ansari, Zehra Hashim, Aftab Ahmed, Shamshad Zarina

Pharmacy Faculty Articles and Research

Background

Current study focused on discovering protein biomarkers from the maternal serum of β-thalassemic trait mothers carrying the normal fetus and β-thalassemic major fetus.

Method

Serum samples from β-thalassemic trait mothers carrying major (N=5) and normal fetuses (N=5) were studied. IVS1-5 thalassemia mutation was common among β-thalassemic trait mothers who were carrying homozygous β-thalassemic fetus (IVS1-5/ IVS1-5 mutation) or normal fetus (no mutation). We employed two-dimensional gel electrophoresis and mass spectrometric analysis to explore differentially expressed maternal serum proteins from thalassemia carrier couples having the same β-thalassemia mutation. Western blotting was performed for one of the identified proteins to validate …


Angiogenesis' Effect Overall On Health And Disease, Wendy Tang 2021 University of Louisville

Angiogenesis' Effect Overall On Health And Disease, Wendy Tang

The Cardinal Edge

Angiogenesis plays a major role in the development of diseases and cancer. The development of illnesses like metastatic breast cancer, cell carcinomas, tumors and various other illnesses, originate from the activation of endothelial cells. When the vascular endothelial growth factor (VEGF) is released from hypoxic tissues, they bind to vascular endothelial growth factor receptors (VEGFR). The binding of VEGF and VEGFR allows for cellular proliferation, increased migration of lattice networks, and the invasion of endothelial cells, which stimulate the formation of new blood vessels from pre-existing ones. As a result, it can be concluded that the inhibition of VEGFs would …


Design And Application Of Hybrid Cyclic-Linear Peptide-Doxorubicin Conjugates As A Strategy To Overcome Doxorubicin Resistance And Toxicity, Saghar Mozaffari, David Salehi, Parvin Mahdipoor, Richard Beuttler, Rakesh Tiwari, Hamidreza Montazeri Aliabadi, Keykavous Parang 2021 Chapman University

Design And Application Of Hybrid Cyclic-Linear Peptide-Doxorubicin Conjugates As A Strategy To Overcome Doxorubicin Resistance And Toxicity, Saghar Mozaffari, David Salehi, Parvin Mahdipoor, Richard Beuttler, Rakesh Tiwari, Hamidreza Montazeri Aliabadi, Keykavous Parang

Pharmacy Faculty Articles and Research

Doxorubicin (Dox) is used for breast cancer, leukemia, and lymphoma treatment as an effective chemotherapeutic agent. However, Dox use is restricted due to inherent and acquired resistance and an 8-fold increase in the risk of potentially fatal cardiotoxicity. Hybrid cyclic-linear peptide [R5K]W7A and linear peptide R5KW7A were conjugated with Dox through a glutarate linker to afford [R5K]W7A-Dox and R5KW7A-Dox conjugates to generate Dox derivatives. Alternatively, [R5K]W7C was conjugated with Dox via a disulfide linker to generate [R5K]W7C–S–S-Dox conjugate, where S–S is a disulfide bond. Comparative antiproliferative assays between conjugates [R5K]W7A-Dox, [R5K]W7C–S–S-Dox, linear R5KW7A-Dox, the corresponding physical mixtures of the peptides, …


Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang 2021 The Graduate Center, City University of New York

Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang

Dissertations, Theses, and Capstone Projects

Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …


The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber 2021 The Graduate Center, City University of New York

The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber

Dissertations, Theses, and Capstone Projects

Light provides organisms with energy and spatiotemporal information. To survive and adapt, organisms have developed the ability to sense light to drive biochemical effects that underlie vision, entrainment of circadian rhythm, stress response, virulence, and many other important molecularly driven responses. Blue-light sensing Light-Oxygen-Voltage (LOV) domains are ubiquitous across multiple kingdoms of life and modulate various physiological events via diverse effector domains. Using a small molecule flavin chromophore, the LOV domain undergoes light-dependent structural changes leading to activation or repression of these catalytic and non-catalytic effectors. In silico analyses of high-throughput genomic sequencing data has led to the marked expansion …


Synthesis, Characterization And Applications Of Peptide-Coated Nanoparticles, Mina Sadat Poursharifi 2021 The Graduate Center, City University of New York

Synthesis, Characterization And Applications Of Peptide-Coated Nanoparticles, Mina Sadat Poursharifi

Dissertations, Theses, and Capstone Projects

Ovarian Cancer (OC) is the most lethal female malignancy worldwide, mainly due to its high recurrence rate and poor diagnosis. Most patients present with late stage of the disease, and less than 25% of patients survive the five years mark. Nanotherapy provides significant and unique benefits for drug efficacy, as nanoparticles (NPs) can increase the solubility, bioavailability, and permeability of many potent drugs. Poly(lactic-co-glycolic acid) (PLGA) is one of the most successful biodegradable polymers used in NPs formulations, mainly due to its biocompatibility and biodegradability. Polyethylene glycol (PEG) is one of the most commonly used moieties to prolong the NPs …


Subtype-Selective Positive Modulation Of KCa 2 Channels Depends On The Ha/Hb Helices, Young-Woo Nam, Meng Cui, Naglaa Salem, Razan Orfali, Misa Nguyen, Grace Yang, Mohammad Asikur Rahman, Judy Lee, Miao Zhang 2021 Chapman University

Subtype-Selective Positive Modulation Of KCa 2 Channels Depends On The Ha/Hb Helices, Young-Woo Nam, Meng Cui, Naglaa Salem, Razan Orfali, Misa Nguyen, Grace Yang, Mohammad Asikur Rahman, Judy Lee, Miao Zhang

Pharmacy Faculty Articles and Research

Background and Purpose

In the activated state of small-conductance Ca2+-activated potassium (KCa 2) channels, calmodulin interacts with the HA/HB helices and the S4-S5 linker. CyPPA potentiates KCa 2.2a and KCa 2.3 channel activity but not the KCa 2.1 and KCa 3.1 subtypes.

Experimental Approach

Site-directed mutagenesis, patch-clamp recordings and in silico modeling were utilized to explore the structural determinants for the subtype-selective modulation of KCa 2 channels by CyPPA.

Key Results

Mutating residues in the HA (V420) and HB (K467) helices of KCa 2.2a channels to their equivalent residues in KCa 3.1 channels diminished the potency of CyPPA. CyPPA elicited …


Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker 2021 University of Nebraska Medical Center

Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker

Theses & Dissertations

Melanoma is the deadliest form of skin cancer, and incidence has continued to increase. Half of all melanomas have a BRAF V600E mutation and respond to MAPK pathway inhibitors, including BRAF inhibitor therapy or BRAF/MEK inhibitor combination therapy, but nearly all patients develop treatment resistance. Melanoma cell lines produce variable results as models of MAPK pathway inhibitor resistance. To better understand how the genomic similarity of a melanoma cell line to patient-derived tumors affects resistance mechanisms, differences in DNA mutations and copy-number alterations were compared between melanoma cell lines profiled by the Cancer Cell Line Encyclopedia and cutaneous melanoma tumors …


Uplc-Ms/Ms Analysis Of The Michaelis-Menten Kinetics Of Cyp3a-Mediated Midazolam 1′- And 4-Hydroxylation In Rat Brain Microsomes, Devaraj Venkatapura Chandrashekar, Barent Dubois, Reza Mehvar 2021 Chapman University

Uplc-Ms/Ms Analysis Of The Michaelis-Menten Kinetics Of Cyp3a-Mediated Midazolam 1′- And 4-Hydroxylation In Rat Brain Microsomes, Devaraj Venkatapura Chandrashekar, Barent Dubois, Reza Mehvar

Pharmacy Faculty Articles and Research

Midazolam (MDZ) is a short-acting benzodiazepine with rapid onset of action, which is metabolized by CYP3A isoenzymes to two hydroxylated metabolites, 1′-hydroxymidazolam and 4-hydroxymidazolam. The drug is also commonly used as a marker of CYP3A activity in the liver microsomes. However, the kinetics of CYP3A-mediated hydroxylation of MDZ in the brain, which contains much lower CYP content than the liver, have not been reported. In this study, UPLC-MS/MS and metabolic incubation methods were developed and validated for simultaneous measurement of low concentrations of both hydroxylated metabolites of MDZ in brain microsomes. Different concentrations of MDZ (1–500 µM) were incubated with …


Anti-Inflammatory And Chemopreventive Activity Of Lunasin From Tofu Whey For The Management Of Gastrointestinal Diseases, Cindy Andrea Nieto Veloza 2021 University of Tennessee, Knoxville

Anti-Inflammatory And Chemopreventive Activity Of Lunasin From Tofu Whey For The Management Of Gastrointestinal Diseases, Cindy Andrea Nieto Veloza

Doctoral Dissertations

Gastrointestinal diseases such as inflammatory bowel diseases (IBD) and colorectal cancer (CRC) are pathological conditions associated with chronic inflammation, characterized by intestinal damage, debilitating symptoms, and detrimental health consequences. The increased risk of CRC in IBD patients, and the adverse effects associated with current therapeutic strategies, point out the need for safer alternatives to reduce chronic inflammation in the bowel. Lunasin is a bioactive peptide naturally occurring in soybeans, with chemopreventive and anti-inflammatory properties demonstrated in several extra-intestinal diseases. However, to date, there is no evidence of the biological activity of lunasin on the gastrointestinal tract as a target site. …


Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky 2021 Bronx Community College

Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky

Open Educational Resources

The goal of this preparatory textbook is to give students a chance to become familiar with some terms and some basic concepts they will find later on in the Anatomy and Physiology course, especially during the first few weeks of the course.

Organization and functioning of the human organism are generally presented starting from the simplest building blocks, and then moving into levels of increasing complexity. This textbook follows the same presentation. It begins introducing the concept of homeostasis, then covers the chemical level, and later on a basic introduction to cellular level, organ level, and organ system level. This …


Modulation Of Antibacterial Activity And Cytotoxicity In Amphipathic Cyclic Peptide [R4w4] Using Histidine Substitution, Ryan Stueber 2021 Chapman University

Modulation Of Antibacterial Activity And Cytotoxicity In Amphipathic Cyclic Peptide [R4w4] Using Histidine Substitution, Ryan Stueber

Pharmaceutical Sciences (MS) Theses

Antibiotics have been the gold standard frontline defense against bacterial infections for decades. At the same time, these infecting bacteria have continued to evolve to resist developed antibiotics in an almost endless cycle. As such, we aim to take an alternative approach utilizing antimicrobial peptides (AMPs) as a means to end this cycle. [R4W4] is among known AMPs that demonstrated antimicrobial activity against methicillin-resistant staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 2.67 μg/mL. This peptide had notably effective antimicrobial activity, especially relative to linear (R4W4). However, it displayed a concerning level of cytotoxicity; eliciting a human embryonic …


Suppression Of Dc-Sign And Gh Reveals Complex, Subset-Specific Mechanisms For Kshv Entry In Primary B Lymphocytes, Nancy Palmerin, Farizeh Aalam, Romina Nabiee, Murali Muniraju, Javier Gordon Ogembo, Jennifer Totonchy 2021 Chapman University

Suppression Of Dc-Sign And Gh Reveals Complex, Subset-Specific Mechanisms For Kshv Entry In Primary B Lymphocytes, Nancy Palmerin, Farizeh Aalam, Romina Nabiee, Murali Muniraju, Javier Gordon Ogembo, Jennifer Totonchy

Pharmacy Faculty Articles and Research

Kaposi sarcoma-associated herpesvirus (KSHV) is the causative agent of multiple cancers in immunocompromised patients including two lymphoproliferative disorders associated with KSHV infection of B lymphocytes. Despite many years of research into the pathogenesis of KSHV associated diseases, basic questions related to KSHV molecular virology remain unresolved. One such unresolved question is the cellular receptors and viral glycoproteins needed for KSHV entry into primary B lymphocytes. In this study, we assess the contributions of KSHV glycoprotein H (gH) and the cellular receptor DC-SIGN to KSHV infection in tonsil-derived B lymphocytes. Our results show that (1) neither KSHV-gH nor DC-SIGN are essential …


Toward The Total Synthesis Of Dragonamide E And Its Potential Medicinal Application Against Leishmaniasis, Nathaniel M. Smith 2021 University of Texas at Tyler

Toward The Total Synthesis Of Dragonamide E And Its Potential Medicinal Application Against Leishmaniasis, Nathaniel M. Smith

Chemistry Theses

Leishmaniasis is one of the world’s most neglected tropical diseases, with hundreds of thousands of cases occurring worldwide annually. The disease originates from being infected by protozoa of the Leishmania genus, which are parasites that destroy mammalian cells as part of their life cycle. Currently utilized treatment strategies for leishmaniasis have many disadvantages, warranting the search for a new leishmaniasis treatment.

Cyanobacteria have been discovered to synthesize a wide variety of cytotoxic chemicals as part of their own defense mechanism. One strain of cyanobacteria, Lyngbya majuscula, produces several families of compounds, one of which is known as the “dragonamides”. …


Dimeric Allostery Mechanism Of The Plant Circadian Clock Photoreceptor Zeitlupe, Francesco Trozzi, Feng Wang, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao 2021 Southern Methodist University

Dimeric Allostery Mechanism Of The Plant Circadian Clock Photoreceptor Zeitlupe, Francesco Trozzi, Feng Wang, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao

Mathematics, Physics, and Computer Science Faculty Articles and Research

In Arabidopsis thaliana, the Light-Oxygen-Voltage (LOV) domain containing protein ZEITLUPE (ZTL) integrates light quality, intensity, and duration into regulation of the circadian clock. Recent structural and biochemical studies of ZTL indicate that the protein diverges from other members of the LOV superfamily in its allosteric mechanism, and that the divergent allosteric mechanism hinges upon conservation of two signaling residues G46 and V48 that alter dynamic motions of a Gln residue implicated in signal transduction in all LOV proteins. Here, we delineate the allosteric mechanism of ZTL via an integrated computational approach that employs atomistic simulations of wild type and …


Human Oncoprotein 5mp Suppresses General And Repeat-Associated Non-Aug Translation Via Eif3 By A Common Mechanism, Chingakham Ranjit Singh, M. Rebecca Glineburg, Chelsea Moore, Naoki Tani, Rahul Jaiswal, Ye Zou, Eric Aube, Sarah Gillaspie, Mackenzie Thornton, Ariana Cecil, Madelyn Hilgers, Azuma Takasu, Izumi Asano, Masayo Asano, Carlos R. Escalante, Akira Nakamura, Peter K. Todd, Katsura Asano 2021 Kansas State University

Human Oncoprotein 5mp Suppresses General And Repeat-Associated Non-Aug Translation Via Eif3 By A Common Mechanism, Chingakham Ranjit Singh, M. Rebecca Glineburg, Chelsea Moore, Naoki Tani, Rahul Jaiswal, Ye Zou, Eric Aube, Sarah Gillaspie, Mackenzie Thornton, Ariana Cecil, Madelyn Hilgers, Azuma Takasu, Izumi Asano, Masayo Asano, Carlos R. Escalante, Akira Nakamura, Peter K. Todd, Katsura Asano

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

eIF5-mimic protein (5MP) is a translational regulatory protein that binds the small ribosomal subunit and modulates its activity. 5MP is proposed to reprogram non-AUG translation rates for oncogenes in cancer, but its role in controlling non-AUG initiated synthesis of deleterious repeat-peptide products, such as FMRpolyG observed in fragile-X-associated tremor ataxia syndrome (FXTAS), is unknown. Here, we show that 5MP can suppress both general and repeat-associated non-AUG (RAN) translation by a common mechanism in a manner dependent on its interaction with eIF3. Essentially, 5MP displaces eIF5 through the eIF3c subunit within the preinitiation complex (PIC), thereby increasing the accuracy of initiation. …


Differential Effect Of Proinflammatory Cytokines On Corneal And Conjunctival Epithelial Cell Mucins And Glycocalyx, Kiumars Shamloo, Priya Mistry, Ashley Barbarino, Christopher Ross, Vishal Jhanji 2021 Chapman University

Differential Effect Of Proinflammatory Cytokines On Corneal And Conjunctival Epithelial Cell Mucins And Glycocalyx, Kiumars Shamloo, Priya Mistry, Ashley Barbarino, Christopher Ross, Vishal Jhanji

Pharmacy Faculty Articles and Research

Purpose: Ocular surface mucins and glycocalyx are critical for providing ocular hydration as well lubrication and repelling pathogens or allergens. Elevated levels of tear proinflammatory cytokines in dry eye may have detrimental effect on mucins and glycocalyx. The present study tested the effect of proinflammatory cytokines IL-6, TNF-α, and IFN-γ on membrane-tethered mucins expression, glycocalyx, and viability of ocular surface epithelial cells.

Methods: Stratified cultures of human corneal and conjunctival epithelial cells were exposed to different concentrations of IL-6, TNF-α, and IFN-γ for 24 hours. The mucins gene and protein expressions were quantified by real-time polymerase chain reaction …


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