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Exploring The Synthesis Of Substituted Porphyrins, Christina Schnee 2019 Elizabethtown College

Exploring The Synthesis Of Substituted Porphyrins, Christina Schnee

Landmark Conference Summer Research Symposium

A current theme in our research laboratory is the development of low cost methods for the synthesis of lamellar vesicles as models for cell membranes. These vesicles, serving as simplified artificial cells, allow us to examine fundamental properties of the membrane including transport of materials across the membrane. Vesicles of varying size can also be employed as molecule delivery systems for a variety of compounds, including pharmaceuticals. We are especially interested in pharmaceuticals used in photodynamic therapy. This type of medical intervention entails delivery of a prodrug (one which is not initially bio-active). Upon exposure to a specific wavelength of ...


Development Of A One-Pot Allylation And Claisen Rearrangement Of Acetaminophen By Applying Microwave Radiation, Brandon R. Tessier 2019 Elizabethtown College

Development Of A One-Pot Allylation And Claisen Rearrangement Of Acetaminophen By Applying Microwave Radiation, Brandon R. Tessier

Landmark Conference Summer Research Symposium

The Claisen rearrangement is a widely applicable organic reaction that involves the shift of a sigma bond across the pi-system of an allyl vinyl ether to produce allylated phenols. In this project, we aim to develop a microwave assisted allylation of a phenol, followed by a subsequent Claisen rearrangement in one pot. The goals of this project are three-fold. First, we aim to accelerate these reactions using microwave assisted organic synthesis because to date, microwave technology has been sparsely used in Claisen chemistry. Second, we aim to perform these reactions in a single pot, enhancing the simplicity and elegance of ...


Regulation Of Rna Stability By Terminal Nucleotidyltransferases, Christina Z. Chung 2019 The University of Western Ontario

Regulation Of Rna Stability By Terminal Nucleotidyltransferases, Christina Z. Chung

Electronic Thesis and Dissertation Repository

The dysregulation of RNAs has global effects on all cellular pathways. The regulation of RNA metabolism is thus tightly controlled. Terminal RNA nucleotidyltransferases (TENTs) regulate RNA stability and activity through the addition of non-templated nucleotides to the 3′-end. TENT-catalyzed adenylation and uridylation have opposing effects; adenylation stabilizes while uridylation silences or degrades RNA. All TENT homologs were initially characterized as adenylyltransferases; the identification of caffeine-induced death suppressor protein 1 (Cid1) in Schizosaccharomyces pombe as an uridylyltransferase led to the reclassification of many TENTs as uridylyltransferases. Cid1 uridylates mRNAs that are subsequently degraded by the exonuclease Dis-like 3′-5′ exonuclease ...


Electron Transfer Activity Of Mitochondria Neet-Proteins, Yiming Wang 2019 Department of Biological Sciences

Electron Transfer Activity Of Mitochondria Neet-Proteins, Yiming Wang

LSU Doctoral Dissertations

Mitochondrial NEET proteins are recently discovered iron-sulfur proteins that are localized within mitochondria. There are three NEET proteins: mitoNEET, a type II diabetes drug pioglitazone binding target, a mitoNEET related protein 1 (Miner1 or NAF-1), and a mitoNEET-related protein 2 (Miner2). While both mitoNEET and Miner1 are mitochondrial outer membrane proteins, Miner2 is a mitochondrial matrix protein. All three NEET proteins bind at least one [2Fe-2S] cluster via CDGSH (Cys-Asp-Gly-Ser-His) motif. In this work, we have investigated the electron transfer activity of mitoNEET, and found that the CDGSH-type [2Fe-2S] clusters of mitoNEET can be reduced by the reduced flavin mononucleotide ...


Rapid Irreversible Transcriptional Reprogramming In Human Stem Cells Accompanied By Discordance Between Replication Timing And Chromatin Compartment, Vishnu Dileep, Rachel Patton McCord, Job Dekker, David M. Gilbert 2019 Florida State University

Rapid Irreversible Transcriptional Reprogramming In Human Stem Cells Accompanied By Discordance Between Replication Timing And Chromatin Compartment, Vishnu Dileep, Rachel Patton Mccord, Job Dekker, David M. Gilbert

Open Access Articles

The temporal order of DNA replication is regulated during development and is highly correlated with gene expression, histone modifications and 3D genome architecture. We tracked changes in replication timing, gene expression, and chromatin conformation capture (Hi-C) A/B compartments over the first two cell cycles during differentiation of human embryonic stem cells to definitive endoderm. Remarkably, transcriptional programs were irreversibly reprogrammed within the first cell cycle and were largely but not universally coordinated with replication timing changes. Moreover, changes in A/B compartment and several histone modifications that normally correlate strongly with replication timing showed weak correlation during the early ...


An Unexpected Rhenium(Iv)–Rhenium(Vii) Salt: [Co(Nh3)6]3[Reviio4][Reivf6]46h2o, James Louis_Jean, Samudee Mariappan Balasekaran, Adelheid Hagenbach, Frederic Poineau 2019 University of Nevada, Las Vegas

An Unexpected Rhenium(Iv)–Rhenium(Vii) Salt: [Co(Nh3)6]3[Reviio4][Reivf6]46h2o, James Louis_Jean, Samudee Mariappan Balasekaran, Adelheid Hagenbach, Frederic Poineau

Chemistry and Biochemistry Faculty Publications

The title hydrated salt, tris[hexaamminecobalt(III)] tetraoxidorhenate(VII) tetrakis[hexafluoridorhenate(IV)] hexahydrate, arose unexpectedly due to possible contamination of the K2ReF6 starting material with KReO4. It consists of octahedral [Co(NH3)6] 3+ cation (Co1 site symmetry 1), tetrahedral [ReVIIO4] anions (Re site symmetry 1) and octahedral [ReIVF6] 2 anions (Re site symmetries 1and 3). The [ReF6] 2 octahedral anions (mean Re—F = 1.834 A˚ ), [Co(NH3)6] 3+ octahedral cations (mean Co—N = 1.962 A˚ ), and the [ReO4] tetrahedral anion (mean Re—O = 1.719 A˚ ) are slightly distorted. A network of N—HF hydrogen bonds ...


Systems Approach Reveals Photosensitivity And Per2 Level As Determinants Of Clock-Modulator Efficacy, Dae Wook Kim, Cheng Chang, Xian Chen, Angela C. Doran, Francois Gaudreault, Travis Wager, George J. DeMarco, Jae Kyoung Kim 2019 Korea Advanced Institute of Science and Technology

Systems Approach Reveals Photosensitivity And Per2 Level As Determinants Of Clock-Modulator Efficacy, Dae Wook Kim, Cheng Chang, Xian Chen, Angela C. Doran, Francois Gaudreault, Travis Wager, George J. Demarco, Jae Kyoung Kim

Open Access Articles

In mammals, the master circadian clock synchronizes daily rhythms of physiology and behavior with the day-night cycle. Failure of synchrony, which increases the risk for numerous chronic diseases, can be treated by phase adjustment of the circadian clock pharmacologically, for example, with melatonin, or a CK1delta/epsilon inhibitor. Here, using in silico experiments with a systems pharmacology model describing molecular interactions, and pharmacokinetic and behavioral experiments in cynomolgus monkeys, we find that the circadian phase delay caused by CK1delta/epsilon inhibition is more strongly attenuated by light in diurnal monkeys and humans than in nocturnal mice, which are common preclinical ...


Identification And Characterization Of Preferred Dna-Binding Sites For The Thermus Thermophilus Hb8 Transcriptional Regulator Ttha0973, James Shell Cox, Kristi Moncja, Mykala Mckinnes, Michael W. Van Dyke 2019 Kennesaw State University

Identification And Characterization Of Preferred Dna-Binding Sites For The Thermus Thermophilus Hb8 Transcriptional Regulator Ttha0973, James Shell Cox, Kristi Moncja, Mykala Mckinnes, Michael W. Van Dyke

Faculty Publications

Advances in genomic sequencing have allowed the identification of a multitude of genes encoding putative transcriptional regulatory proteins. Lacking, often, is a fuller understanding of the biological roles played by these proteins, the genes they regulate or regulon. Conventionally this is achieved through a genetic approach involving putative transcription factor gene manipulation and observations of changes in an organism’s transcriptome. However, such an approach is not always feasible or can yield misleading findings. Here, we describe a biochemistry-centric approach, involving identification of preferred DNA-binding sequences for the Thermus thermophilus HB8 transcriptional repressor TTHA0973 using the selection method Restriction Endonuclease ...


Molecular And Structural Mechanism Of Pan-Genotypic Hcv Ns3/4a Protease Inhibition By Glecaprevir, Jennifer Timm, Klajdi Kosovrasti, Mina Henes, Florian Leidner, Shurong Hou, Akbar Ali, Nese Kurt Yilmaz, Celia A. Schiffer 2019 University of Massachusetts Medical School

Molecular And Structural Mechanism Of Pan-Genotypic Hcv Ns3/4a Protease Inhibition By Glecaprevir, Jennifer Timm, Klajdi Kosovrasti, Mina Henes, Florian Leidner, Shurong Hou, Akbar Ali, Nese Kurt Yilmaz, Celia A. Schiffer

University of Massachusetts Medical School Faculty Publications

Hepatitis C virus (HCV), causative agent of chronic viral hepatitis, infects 71 million people worldwide and is divided into seven genotypes and multiple subtypes with sequence identities between 68 to 82%. While older generation direct-acting antivirals (DAAs) had varying effectiveness against different genotypes, the newest NS3/4A protease inhibitors including glecaprevir (GLE) have pan-genotypic activity. The structural basis for pan-genotypic inhibition and effects of polymorphisms on inhibitor potency were not well known due to lack of crystal structures of GLE-bound NS3/4A or genotypes other than 1. In this study, we determined the crystal structures of NS3/4A from genotypes ...


Hexavalent Chromium-Induced Cytotoxicity And Mutagenicity: A Study Of Protection By Ascorbic Acid And Epigallocatechin Gallate, Timothy P. Mayotte 2019 Olivet Nazarene University

Hexavalent Chromium-Induced Cytotoxicity And Mutagenicity: A Study Of Protection By Ascorbic Acid And Epigallocatechin Gallate, Timothy P. Mayotte

Honors Program Projects

Hexavalent chromium, or Cr(VI), is a potent oxidizer and known carcinogen, that is found at varying levels in the water sources of more than 200 million Americans. However, the exact mechanism of carcinogenicity remains unknown, and though the government currently regulates total chromium levels, they have yet to determine a permissible exposure limit for Cr(VI). Moreover, there is currently no preventative treatment for Cr(VI). Because of Cr(VI)’s strong oxidative power, we hypothesized that it causes DNA mutation and cell death via oxidation and that antioxidants could prevent this from occurring. To test this, we first ...


Organic Chemistry With A Biological Emphasis Volume I, Timothy Soderberg 2019 University of Minnesota Morris Digital Well

Organic Chemistry With A Biological Emphasis Volume I, Timothy Soderberg

Chemistry Publications

The traditional approach to teaching Organic Chemistry, taken by most of the textbooks that are currently available, is to focus primarily on the reactions of laboratory synthesis, with much less discussion - in the central chapters, at least - of biological molecules and reactions. This is despite the fact that, in many classrooms, a majority of students are majoring in Biology or Health Sciences rather than in Chemistry, and are presumably taking the course in order to learn about the chemistry that takes place in living things.

In an effort to address this disconnect, I have developed a textbook for a two-semester ...


The Expression Of Connexin-43 By Cd11c+ Dendritic Cells Is Required To Maintain Cd4+ Foxp3+ Regulatory T Cell Population In Peripheral Lymphoid Organs, Caroline Titus Miller 2019 Old Dominion University

The Expression Of Connexin-43 By Cd11c+ Dendritic Cells Is Required To Maintain Cd4+ Foxp3+ Regulatory T Cell Population In Peripheral Lymphoid Organs, Caroline Titus Miller

Biological Sciences Theses & Dissertations

Foxp3+ regulatory T cells (TR) are an immunosuppressive subset of CD4+ T cells that maintain homeostasis of the immune system. They are sustained by the interaction between the Major Histocompatibility Complex (MHC) molecules present on antigen presenting dendritic cells and the T Cell Receptor (TCR) expressed on TR cells that is specific for the MHC loaded with an antigenic peptide. Here, we show that in addition to MHC/TCR interaction, Connexin-43 (Cx43) expression by dendritic cells is required to maintain the TR cell population. CD11c+ dendritic cells represent a major subset of antigen presenting cells. Using flow cytometry ...


Organic Chemistry With A Biological Emphasis Volume Ii, Timothy Soderberg 2019 University of Minnesota Morris Digital Well

Organic Chemistry With A Biological Emphasis Volume Ii, Timothy Soderberg

Chemistry Publications

The traditional approach to teaching Organic Chemistry, taken by most of the textbooks that are currently available, is to focus primarily on the reactions of laboratory synthesis, with much less discussion - in the central chapters, at least - of biological molecules and reactions. This is despite the fact that, in many classrooms, a majority of students are majoring in Biology or Health Sciences rather than in Chemistry, and are presumably taking the course in order to learn about the chemistry that takes place in living things.

In an effort to address this disconnect, I have developed a textbook for a two-semester ...


Endogenous Force Transmission Between Epithelial Cells And A Role For Α-Catenin, Sandeep Dumbali 2019 Old Dominion University

Endogenous Force Transmission Between Epithelial Cells And A Role For Α-Catenin, Sandeep Dumbali

Mechanical & Aerospace Engineering Theses & Dissertations

In epithelial tissues, epithelial cells adhere to each other as well as to the underlying extra-cellular matrix (ECM). E-cadherin-based intercellular junctions play an important role in tissue integrity. These junctions experience cell-generated mechanical forces via apparent adaptor proteins such as beta (β) catenin, alpha (α) catenin and vinculin. Abnormalities in these junctions may result in skin related diseases and cancers. Here, I devised methods to determine the endogenous intercellular force within cell pairs as well as in large epithelial islands. I further ascertained the factors that affect the level of inter-cellular tension.

Experiments with pairs of epithelial cells exogenously expressing ...


Tracing Nutrient Sources To Lipid Production In Insects Using Stable Isotope (Δ13c, Δ2h) Tracers: Implications For Nutritional Physiology Of Migratory Species., Libesha Anparasan, Keith A. Hobson 2019 The University of Western Ontario

Tracing Nutrient Sources To Lipid Production In Insects Using Stable Isotope (Δ13c, Δ2h) Tracers: Implications For Nutritional Physiology Of Migratory Species., Libesha Anparasan, Keith A. Hobson

Western Research Forum

Using stable isotope measurements of insect tissues to determine origin and migratory patterns is well established. However, isotopically determining nutritional origins of lipids, the primary fuel of migration, has not been as thoroughly researched. We explored isotopic links between diet and stored lipids in laboratory raised True armyworm moths (Mythimna unipuncta) using δ13C and δ2H measurements. Pupae were randomly separated into four groups (n=20) and fed isotopically distinct nectar, each consisting of a combination of high δ13C (C4 sugar), or low δ13C (C3 sugar) carbohydrate, with high δ2H (deuterium ...


Knocking Out A Negative Regulator Of Hedgehog Signaling Blocks Differentiation Of Cells Into Neurons, Danielle Margaret Spice, Gregory M. Kelly Ph.D. 2019 Western University

Knocking Out A Negative Regulator Of Hedgehog Signaling Blocks Differentiation Of Cells Into Neurons, Danielle Margaret Spice, Gregory M. Kelly Ph.D.

Western Research Forum

Hedgehog (Hh) signaling, one of many different protein signaling pathways found in mammals, is vital in many stage of neural development. A major negative regulator of Hh signaling is a protein known as Suppressor of Fused (SUFU), which acts to sequester the full length Gli transcription factors, proteins that can turn genes on and off, in the cytoplasm or facilitates its conversion to a repressive form. The P19 embryonal carcinoma cell line is a model of hind-brain neuronal differentiation and the involvement of Hh signaling, in particular the role of SUFU in this process has yet to be explored. We ...


The Wet Bridge Transfer System: An Novel In Vitro Tool For Assessing Exogenous Surfactant As A Pulmonary Drug Delivery Vehicle, Brandon J. Baer 2019 University of Western Ontario

The Wet Bridge Transfer System: An Novel In Vitro Tool For Assessing Exogenous Surfactant As A Pulmonary Drug Delivery Vehicle, Brandon J. Baer

Western Research Forum

Background:

Due to its complex branching structure, direct drug delivery to the remote areas of the lung is a major challenge. Consequently, most therapies, such as those treating pulmonary infection and inflammation, must utilize large systemic dosing, with the potential for adverse side effects. A novel alternative strategy is to use exogenous surfactant, a material capable of distributing throughout the lung, as a pulmonary drug delivery vehicle.

Objective:

Utilize an in vitro transferring system to assess exogenous surfactant (BLES) as a pulmonary delivery vehicle for different therapeutics.

Methods:

An in vitro technique was developed to simultaneously study surfactant delivery and ...


Iron-Sulfur Cluster Biosynthesis In Methanogens, Cuiping Zhao 2019 Louisiana State University and Agricultural and Mechanical College

Iron-Sulfur Cluster Biosynthesis In Methanogens, Cuiping Zhao

LSU Doctoral Dissertations

Methanogens live in a syntrophic consortium with bacteria, taking advantage of the metabolic abilities of their syntrophic partners to overcome energetic barriers and break down compounds that they cannot digest by themselves. Interspecies electron transfer, which is a major type of microbial communication in syntrophic processes, improves methanogenesis and anaerobic oxidization of methane (AOM) processes involved in syntrophic consortia. These processes have a significant impact on the global carbon cycle. Most of the essential enzymes involved in methanogenesis are iron-sulfur proteins. Iron-sulfur clusters are one of the oldest and most versatile cofactors present in all domains of life. To date ...


Inhibition Of Crispr-Cas9 Ribonucleoprotein Complex Assembly By Anti-Crispr Acriic2, Annoj Thavalingam, Erik J. Sontheimer, Yanli Wang, Karen L. Maxwell 2019 University of Toronto

Inhibition Of Crispr-Cas9 Ribonucleoprotein Complex Assembly By Anti-Crispr Acriic2, Annoj Thavalingam, Erik J. Sontheimer, Yanli Wang, Karen L. Maxwell

Open Access Articles

CRISPR-Cas adaptive immune systems function to protect bacteria from invasion by foreign genetic elements. The CRISPR-Cas9 system has been widely adopted as a powerful genome-editing tool, and phage-encoded inhibitors, known as anti-CRISPRs, offer a means of regulating its activity. Here, we report the crystal structures of anti-CRISPR protein AcrIIC2Nme alone and in complex with Nme1Cas9. We demonstrate that AcrIIC2Nme inhibits Cas9 through interactions with the positively charged bridge helix, thereby preventing sgRNA loading. In vivo phage plaque assays and in vitro DNA cleavage assays show that AcrIIC2Nme mediates its activity through a large electronegative surface. This work shows that anti-CRISPR ...


"Flagella Base Model" And "Flagellin Monomer", Brandon Lasalle, Rebecca Roston 2019 University of Nebraska- Lincoln

"Flagella Base Model" And "Flagellin Monomer", Brandon Lasalle, Rebecca Roston

3-D printed model structural files

"Flagella Base Model" and "Flagellin monomer"

Description: This is a teaching model of the proteins that make a bacterial flagella. All models are depicted in space-fill. The Flagellin monomer and the Flagella base can slot together to show protein quaternary structure and filamentous protein assembly.

Printable models are already uploaded to Shapeways.com in the MacroMolecules shop under the names "Flagella Base Model" and "Flagellin monomer".

This model has been printed successfully using these parameters on Shapeways’ laser sintering printer in the following material: Processed Versatile Plastic (Strong & Flexible Plastic).

Model designer: Brandon Lasalle Authors: Brandon Lasalle and Rebecca Roston ...


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